Friday, March 31, 2006

Links, Links, Links

I've decided that, for now, I'm going to do this link post thing every now and then, because I always like when Brandon does it, and hey, I've stolen just about every aspect of my blog personality from him, Richard, and Clark, so what's one more theft? Plus, there's a lot of cool stuff out there, and I might have noticed some of it that you didn't.

First up is Heo Cwaeth's fourth installment in her "Medieval Women I Adore" series. This one is on Hrotswitha von Gandersheim (try saying that 5 times fast!), about whom she writes:
My love for this woman comes not only from her desire to defend the role of women in Christianity at such an early stage, but from her absolute refusal to feign idiocy. In fact, she considers her intellect a gift from God that she is required to use. Doesn't get better than that in the tenth century, folks.
Plus, did you know that she was the first European woman known to have written literary works? Now you do. As usual, Heo manages to make me adore Hrotsw... you know who I mean, too.

Next, Carl Zimmer discovers that what looks like a myth about the brain, that it can perform a massive amount of calculations using only 10 watts, is true, even though it may have originated with the poet Paul Valery.

John Hawks has a nice post on two recent papers concerning off-line memory consolidation while we're awake. Very interesting stuff on a very poorly understood topic.

Via Omni Brain, "The Seven Warning Signs of Bogus Science."

Also, March saw the birth of a great new blog, Stop that Crow! You should stop by and read everything, but I recommend starting with this one on similarity-based theories of concepts.

And finally, Cognitive Daily talks about The Emotion of Shapes.

Bilingualism = Multiple Personality Disorder?

OK, this (via Mind Hacks) is just cool, even if I don't know quite how seriously to take it. Apparently there's been a fair amount of research over the last few years on changes in attitudes, values, and behaviors that occur when bilinguals (or multilinguals) switch between languages. For example, in one study (p. 2):
Hong Kong bilingual-Chinese managers who responded to a values questionnaire in English displayed means closer to a group of American managers in the US than did the bilingual-Chinese managers who responded to the same questionnaire in Chinese (Ralston et al., 1995).
The explanation, which the authors of the linked study (two of whom I know pretty well personally, and still had never heard of this stuff) attribute to "Cultural Frame Switching" or "cultural accomodation," is that the language primes the culture that goes with it, and the cultures values and atitudes are thus primed as well. You know, I can almost buy that.

But for social psychologists, the mere priming of values and attitudes is not sexy enough. They need something bigger; they need to show that switching between languages causes personality changes. Of course, this requires showing something equally sexy, namely that differences in personality exist between Spanish and English speakers in the first place. So the paper is, like, doubly sexy ("sexy" is, of course, a technical term in social psychology, and doesn't refer to anything related to actual sex... I hope).

In the first study, they administered the Big Five Inventory, which measures the Big Five personality dimensions, to 168, 451 (yes, that's a lot) English-speaking participants in the United States, and 1031 Spanish-speaking participants living in Mexico. They found small, but statistically different differences on all 5 dimensions (with samples that large, it's no wonder), such that the English-speakers scored higher on the Extraversion, Agreeableness, Conscientiousness, and Openness dimensions, while the Spanish-speakers scored higher on the Neuroticism dimension.

Using this finding, they then predicted that if bilinguals take the BFI in both languages, they will score higher on Extraversion, Agreeableness, Conscientiousness, and Openness when they take it in English, and higher on Neuroticism when they take it in Spanish. In three studies, with a combined sample of 249 English-Spanish bilinguals in Mexico and the United States, they found differences in the predicted directions on four of the five dimensions, with the difference on the Openness dimension being in the opposite direction, though not statistically significant. The difference between the scores on the Spanish and English versions on the Neuroticism dimension, while in the predicted direction, was also not statistically significant.

Once again, the authors interpret these results in terms of Cultural Frame Switching. They also make it clear that, while they found small changes in personality within individuals, the correlation between scores on the English and Spanish tests, across all participants, was 0.8. This implies that the differences between the scores for a single individual on the two versions of the test were relative. If one person takes the test in English and scores higher on the Extraversion dimension than another person did on the English version, it's likely that the first person will also score higher on the Extraversion dimension on the Spanish version than the second will on the Spanish version. Thus, switching languages isn't really altering your personality all that much. It's just tweaking the levels a little. And switching between Spanish and English doesn't seem to change your level of openness at all. I guess openness isn't as prone to priming effects as, say, extroversion. So, if you're an overly close-minded Spanish speaker, I'm afraid that learning English and speaking it exclusively probably won't help. But if you're an introverted Spanish speaker with a messy bedroom (Conscientiousness), and you want to have more fun at parties and finally clean that room, then by all means, learn English.

Wednesday, March 29, 2006

Upcoming on Mixing Memory

I've got a few posts stewing on the following topics:
  • Essentialism about social concepts
  • Motivated cognition outside of politics
  • Cultural differences in cognition
  • Memetics
These seem to be topics that garner a lot of interest. But I'd also like to take suggestions and requests. If there's a topic on cognition, perception, neuroscience, or something related, that you'd like to hear about, let me know. If I know enough about it to post on it, I will. So, leave me a comment or drop me an email.

Tuesday, March 28, 2006

Richards Politics and Personality Meme

As some of you may remember, way back when, Richard of Philosophy, etcetera started a meme in which bloggers took both the IPIP-NEO personality test and the Political Compass quiz, and reported their results (if you want to participate, take the tests now, before reading on). Richard has posted the results, but I thought I'd say a little bit more about them. Naturally, none of these results should be treated as scientific, because, well, they're not. In addition to the fact that neither the online IPIP-NEO or the Political Compass are great tests, the sample was pretty skewed towards the Left and (Social) Libertarian ends of the Political Compass scales, as indicated in the two histograms below.
The scales both go from -10 to +10, with -10 representing the most extreme Left/Libertarian score, and +10 the most extreme Right/Authoritarian score. As you can see, there weren't many bloggers on the Authoritarian end of the Libertarian-Authoritarian scale (16 out of 89, or 18%), and there were relatively few on the Right end of the Left-Right scale (23 out of 89, or 26%). Furthermore, on both scales, those on the Left and Libertarian ends tended to be more extreme than those on the Right and Authoritarian ends. The mean for those on the Left end was -5.6 (median = -5.88), while the mean for those on the left was 4.4 (median = 4.0). The difference is even bigger for the Libertarian-Authoritarian scale. The mean for those on the Libertarian end was -5.3 (median = -5.3), while the mean for those on the Authoritarian end was 2.3 (median = 1.7). In both cases, the differences in extremity are statistically significant. The one good thing the political compass results have going for them is that they seem fairly consistent with the bloggers' self-identification as either liberal or conservative.

The point of all that is simply to make it clear that, if you wanted to compare the relationships between the scores on the compass to the scores on the personality test, this isn't the sample to do it, because it's so heavily skewed. The fact that 67% of the bloggers who gave their results were male doesn't help either. But because this is a blog, and not a scientific journal, I'm going to report the results anyway. Just remember, "bullshit" would be a good word to describe these results. But it's interesting bullshit.

Since the interesting correlations were between the personality variables and the two political compass scores, I'll focus on those. I will quickly note, however, that there were no statistically significant correlations between the personality variables and either age or sex, though the correlation between age and artistic interest (.21) was pretty damn close. It indicates that as people got older, their artistic interest grew. Don't ask me what that might mean (young people and their terrible music! bah!). Also, the correlation between the Left-Right and Libertarian-Authoritarian scales was high (.75) and statistically significant.

For simplicity's sake, I'll report all statistically significant correlations between the compass scores and personality variables as being positive, with those that were negative (i.e., personality scores went up as individuals became more Left or Libertarian) being reported as positive correlations with Left/Libertarian. On the personality test, there were 5 personality categories (Extraversion, Agreeableness, Conscientiousness, Neuroticism, and Openness to Experience), the Big Five. Within each category there were 6 additional variables, each with its own score. First the correlations for the categories. Conscientiousness was positively correlated Right (.23) and Authoritarianism (.22), Agreeableness was positively correlated with Left (.22), and Openness to Experience was positively correlated with both Left (.63) and Libertarian (.66). For the variables within the categories, only one was significantly correlated with either Right or Libertarian. Dutifulness, which is in the Conscientiousness category, was positively correlated with Authoritarian (.23). There were a bunch of significant correlations with Left and Libertarian among the variables within the categories, so instead of writing them all out, I'll just let you read this table:

As you can see, all six of the variables in the Openness to Experience category were positively correlated with both Left and Libertarian, with some of the correlations in the moderate to high range. I suppose it's a good thing that the personality variable Liberal correlated with Left, and that the correlation between Liberal and Libertarian was about the same as that between Left and Libertarian.

Before signing off, I should make a few comments (because I like to hear the sound of my own typing). I think it's interesting that these results are somewhat consistent with the two highly controversial studies I mentioned in a recent post. The correlations between the Left and the category Openness to Experience, as well as Imagination, Artistic Interests, Adventurous, and Intellectual are consistent with the Jost et al. results. I suppose the correlation between Left and Sympathy could be consistent with those results as well, as could the correlation between Authoritarian and Dutifulness. I suppose the fact that this sample was hardly representative of the population as a whole is another point of consistency. Also, it might be interesting to note that the correlation between depression and Left and Depression is consistent with the literature showing that conservatives/Republicans tend to rate themselves as being happier. I don't know what the hell the correlation between Emotionality and Left means. Maybe it's why they call 'em "bleeding heart liberals."

So there you have it, the results of Richard's meme. They're kind of interesting, somewhat consistent with what I think many of us would expect, and entirely meaningless. I don't know if you could ever get a truly representative sample through blogs (though it can't be any less representative that a sample of college undergrads), but it would be nice to have a more even distribution on both the Left-Right and Libertarian-Authoritarian scores. I suppose it's skewed because Richard and the other blogs that picked it up are mostly read by us lefties, though it's mighty tempting to say that the skew is because Richard's blog is a philosophy blog, and Intellectual is positively correlated with Left and Libertarian (that's really meant as a joke, folks).

Saturday, March 25, 2006

Dennett on Religion on the Radio

Daniel Dennett, bringing out the "sweet tooth" metaphor again, was the primary guest on a Radio Open Source show titled "Is God in Our Genes?"(this is the link to the mp3 file of the show). His main point, which I assume is the main point of his recent book, is that religion is an appropriate topic for scientific study. He's preaching to the choir with me, of course. I've tossed around a few ideas for experiments on memory and religion (in line with Atran's work), so I have no compunction in studying religion scientifically. But apparently some people do, perhaps because they're afraid that explaining religion will cause it to lose some of its value (or maybe just because they don't like hearing this stuff from a man who looks like Santa Claus).

Dennett starts to lose me when he gets into memetics, which I find utterly worthless, and as you might expect, he focuses a lot on evolutionary explanations of religion's origins, which I also find pretty worthless, but for the most part the interview is interesting. He's joined on the show by two evolutionary biologists, an Episcopal minister, and a philosopher of religion, each of whom has something interesting to say. So if you're into the psychology or biology of religion, you might find the interviews interesting, and if you plan to read Dennett's book, it seems to provide a nice preview of what you'll find in it. (I haven't read the book myself, but I suspect that Razib's giving good advice when he says that you should just go to the primary sources.)

Friday, March 24, 2006

Leiter and Weisberg on Evolutionary Psychology

Brian Leiter and Michael Weisberg have written an article, available here, titled "Why Evolutionary Psychology Is (So Far) Irrelevant to Law." It has three sections, the first and third arguing against the relevance of EP to law, and the second presenting criticisms EP itself. The arguments in the first and third sections are interesting (and new to me, at least), but I'm naturally more interested in the criticisms of EP itself in the second section. None of those criticisms are new. Most of them come from authors whose work on EP many of you have probably read, such as Elisabeth Lloyd (e.g., in this paper, and this one), Stephen J. Gould, David Buller, Jerry Fodor, the Panskepps, etc. (heck, I offered one of the arguments in a post back in 2004). But it is a nice review of those criticisms. If you're not familiar with those authors' writings on EP, the Leiter and Weisberg article might be of interest to you. Just to give you the gist, most of the criticisms concern the methodological and theoretical connections between EP and contemporary biology. The problem with EP is that there are no such connections. EP relies on a fairly antiquated evolutionary framework, and its methodology -- to look for behaviors that fit with evolutionary reasoning, rather than to use evolutionary reasoning to explain the origins of observed behaviors -- is the exact opposite of what biologists generally do.

I do want to note that the article suffers from a common problem in discussions of EP outside of psychology (especially those by philosophers): very few citations of actual work by Evolutionary Psychologists. It seems strange, to me at least, to offer criticisms without actually citing examples of what you are criticizing. I hesistate to speculate that this occurs due to a lack of familiarity with the literature (though I'm pretty sure that's what got Buller into trouble), but it does lead to problems. For example, I still think Leiter and Weisberg's criticisms miss the mark, partially, by misrepresenting the reasons Evolutionary Psychologists argue for adaptationist explanations. While I think they're right in claiming that there may be many possible non-adaptationist answers for most, if not all EP findings, by mistakenly believing that Evolutionary Psychologists simply assume adaptationist explanations, they leave themselves open to the reply that such explanations are not assumed, but empirically tested, and since predictions derived from those explanations have been empirically confirmed, the burden of proof is on those who believe there may be alternative, non-adaptationist explanations. Of course, the empirical tests used by EP leave much to be desired, both from the perspective of empirical psychology and of evolutionary biology. But still, I think that philosophers and biologists criticizing EP would do well to cite more than one or two examples of actual EP research (or at least be familiar with more than one or two examples).

Do Whiny Kids Become Conservatives?

The study that's getting a lot of attention in the blogosphere, presenting data showing that differences in preschool are correlated with differences in adult political orientation, can be read here. The criticisms seem to be largely based on speculation, but I have to admit, it's hard to evaluate the study from the write-up, because it doesn't give any representation of the distribution of political orientation, and in order to get the data on things like SES, you have to read 25-year old write-ups of previous studies using the same data. It also seems natural to worry about the sample, since it comes from a town notorious for its progressive residents. As some of this post's commenters noted, it could just be that whiny kids grow up to be "hostile to their environment," and since the Berkeley environment is decidedly liberal, these particular kids grew up to be conservative. However, I will note that the study uses widely accepted methodologies and produces results that are, in many cases, highly statistically significant.

The one thing the study appears to have going for it is that its results, at least for the correlations between the adult personality measures and political orientation, are consistent with the work of John Jost and his colleagues (you can read their papers here and here, the second paper being a response to this paper). Recall that they found political conservativism to be positively correlated with death anxiety; system instability (i.e., things like social, economic, and political threats increase conservativism); dogmatism-intolerance of ambiguity; need for order, structure, and closure; and fear of threat and loss; and negatively correlated with openness to experience; uncertainty tolerance; integrative complexity (which just means cognitive complexity); and self esteem (though this negative correlation was fairly small). Since the Block and Block study found conservativism to be negatively correlated with things like "enjoys aesthetic impressions," "complicates simple situations," "has a wide range of interests," "tends to be rebellious, non-conforming," and positively correlated with things like "uncomfortable with uncertainty," and "behaves in a sex-typed manner," the two studies seem to line up fairly well. Of course, the Jost study has been widely criticized by conservatives, but the methods and data seem pretty sound to me. You can check out the papers and judge for yourself.

Tuesday, March 21, 2006

Motivated Reasoning II: Are Political Partisans Irrational?

Your response, I imagine, is "duh." Partisans are emotional; stop the presses, get me rewrite. Perhaps. But I find the graphic clarity of colorful brain scans to be sobering. It'’s one thing to know that some people get obnoxious during political arguments; it's another thing to see that 30 adult men who read candidates' quotes while strapped down in MRI machines didn't even fire up the thinking parts of their brains. - Dick Meyer, in his column on the Westen et al. study

"Didn't even fire up the thinking parts of their brains." Let me quote that one more time. "Didn't even fire up the thinking parts of their brains." When I read something that stupid in an article in the mainstream media, an article linked and quoted by many bloggers, I am at a loss for words. OK, maybe not a loss; an excess, really, if you consider how long the last post was, and that it was only the first in a two-part series. But I really am blown away. You don't even have to have read anything about the study to know that Meyers must be wrong. That's just not how the brain works. But since he's spread that nonsense all over the web, I feel it's important to explain exactly what the study does show. So, after giving the background of the study in the last post, I'm ready to talk about the methods, results, and conclusions of the study in this one. If you'd like to read the unpublished write-up of the study yourself, you can request a copy from Westen here1.

The study begins from the following position (p. 3):
Neural network models of motivated reasoning suggest that in affectively relevant situations, the brain equilibrates to solutions that simultaneously satisfy two sets of constraints: cognitive constraints, which maximize goodness of fit to the data, and emotional constraints, which maximize positive affect and minimize negative affect.
In other words, as I described in the post yesterday, there are two systems at work in motivated reasoning: a cold system, that works to come to an accurate conclusion given the input from the environment and memory, and a hot system, driven by emotion, that seeks to come to a desired conclusion (and thus "maximize positive affect and minimize negative affect") by biasing the input and interpretation of information from the environment and memory with which the cold system can work.

The study is concerned specifically with how political partisans, people who are committed to one political party, and specifically to one candidate, utilize the "hot" and "cold" systems in reasoning when presented with "threatening" information about that candidate. Utilizing imaging work like that of Goel and Dolan (discussed in yesterday's post), Westen et al. predict that when partisans are presented with threatening information about their candidate, they will see increased activation in areas associated with "hot" cognition, specifically the ventromedial prefrontal cortex and the anterior cingulate cortex (an area associatwiththe emotion and reward), along with suppression of activity in areas associated with "cold" cognition, such as the lateral prefrontal cortex.

During the 2004 presidential campaign, Westen et al. recruited 28 right-handed men between the ages of 22 and 55 who were self-reported "committed Republicans or Democrats." They presented each participant with a series of statements either about their favored candidate (same party condition), about the opposing candidate (opposing party condition), or about a "politically neutral" individual (Tom Hanks, Hank Aaron, or William Styron; neutral party condition). I'll let Westen et al. describe the statements (p. 5):
Each statement set consisted of seven slides presenting verbal material, designed to present a clear contradiction between the target person'’s words and actions and then to resolve that contradiction... Slide 1 presented an initial statement, usually a quote from the target individual. Slide 2 presented a contradictory statement suggesting that the target'’s words and actions were inconsistent. Slide 3 asked subjects to consider whether the target's “statements and actions are inconsistent with each other,” and Slide 4 asked them to rate the extent to which they agreed that the target'’s words and deeds were contradictory, from 1 (strongly disagree) to 4 (strongly agree) using a four-button pad. Slide 5 presented an exculpatory statement that explained away the inconsistency. Slide 6 then asked subjects to consider whether the target'’s “statements and actions are not quite as inconsistent as they first appeared.” The final slide asked them once again to rate the extent to which they agreed with this statement, using the same 4- point scale.
The key slides for the data analysis are those that present the contradiction (Slide 2) and those that present an exculpatory statement (Slide 5). Both slides present what are, in fact, contradictions to earlier information. The difference between the two is that, iin the same party condition, the contradiction slide gets inachievingof acheiving a desired conclusion, and thus should elicit motivated reasoning by triggering a negative emotional response, while the exculpatory statement allows the participant to arrive at his desired conclusion using cold cognition exclusively. Thus, based on the predictions described above, we would expect there to be more activity in the "hot" system areas while reading the contradiction slide than while reading the exculpatory slide. We would also expect their to be more activity in the "hot" system after reading the contradiction slide in the same party condition than in the neutral condition.

To test these predictions, Westen et al. performed four contrasts using the subtraction method. The first contrast involved subtracting the brain activity observed during the contradiction slide in the neutral condition from the activity observed during the contradiction slide in the same party condition. The results of this contrast can be seen in this figure (Figure 3 from Westen et al.):

As the figure indicates (in case you couldn't tell), this is what they found (p. 7, all emphasis mine):
[P]rocessing emotionally threatening information about one's preferred candidate relative to a neutral target activated distributed sites in medial prefrontal cortex, including particularly the ventral ("affective"”) subdivision of the [anterior cingulate cortex] but also the more rostral ("“cognitive"”) subdivision. Also activated were a small superior medial prefrontal region and a larger ventromedial region of [the prefrontal cortex] associated with affective processing. The other notable finding was a large area of activation in the posterior cingulate cortex (along with coextensive regions of the precuneus and inferior parietal cortex), associated in prior studies with neural information processing related to social emotions, moral evaluations, and judgments of forgivability.
To summarize the findings of the first contrast: relative to the neutral condition (let me repeat that again, for Meyer and anyone who read him, relative to the neutral condition), they found increased activation in areas associated with emotion and affect while reading the contradiction slide in the same party condition. Note, however, that they also found some increased activity in areas associated with cognitive processing, as well.

The second contrast tested the prediction that there would be a difference between the contradiction and exculpatory slides within the same party condition. Thus, the activity observed while reading the exculpatory slides was subtracted from the activity observed while reading the contradiction slide, all within the same party condition. This is what they found (p. 8, the figure is Figure 5 from Westen et al., all emphasis mine):

The contrast analysis showed activations in the left lateral inferior frontal cortex and left insula (not shown: maximum at -36, -18, 18), both consistent with processing of negative affect. Also seen were activations in the inferior orbitofrontal cortex (gyrus rectus) bilaterally, indicative of emotion processing as well as the precuneus (suggesting evaluative judgments, as above). The only other prominent activations were bilateral activations in the parahippocampal gyrus and extending to the hippocampus, perhaps indicative of efforts to generate solutions (rationalizations) based on memory retrieval. We again observed no differential activation of [dorsal lateral prefrontal cortex], suggesting that motivated reasoning did not engage regions previously linked with conscious attempts to reason, suppress information, or regulate affect.
To summarize, in the same party condition they found increased activation in response to the contradiction, relative to the exculpatory statement, in areas consistent with negative emotional experiences, evaluation, and according to their speculative interpretation, "efforts to generate solutions (rationalizations) based on memory retrieval). Both of these contrasts are thus consistent with the hypothesis that partisans are engaged in motivated reasoning, i.e., biased interpretations, evaluations, and memory searches, in response to threatening information about their favored political candidate (I won't get into the third contrast, because it's a bit complex, but its results are consistent with the first two).

The fourth contrast, which many reporters and bloggers seem to have found incredibly interesting, was, the author admitted, more exploratory than the first three. It was designed to test the hypothesis that the motivated reasoning that occurred while reading the contradictory slide would reduce negative affect. They thus contrasted the activity observed while reading the slide (slide 3) that was shown after the contradictory slide (which was slide 2). If motivated reasoning serves to decrease negative emotional responses to the threatening material, then we would expect a decrease in the activation in areas associated with negative emotional responses (e.g., the left insular cortex). And that is, in fact, what they found: relative to the contradictory slide, activation in areas associated with negative emotions, such as the insular cortex and the lateral orbital frontal cortex decreased significantly. Activation was also seen in the anterior cingulate cortex (suggesting the processing of emotion, though not necessarily negative emotion), and in the left inferior regions of the parietal lobe (suggesting "effortful processing," or as Westen et al. speculate, "rationalization). Finally (and this is what the reporters and bloggers found so sexy), they also found increased activation in the ventral striatum, an area associated with the brain's reward system.

Summarizing all that jargon: when looking at the slide that follows the activation of motivated reasoning, they found decreased activation in areas associated with negative emotions, but continued processing of emotional information, along with areas potentially associated with rationalization (attempting to come up with a post hoc explanation for arriving at one's desired conclusion), and activation indicating that overcoming the threatening information and arriving at the desired conclusion (and the participants did arrive at the desired conclusion, as indicated by their ratings of the candidates) is rewarding. How was this reported by Meyer and others? Overcoming the threat activates the same areas of the brain that are activated by drug use and sex! Well, duh. So is any other rewarding experience (like, say, correctly classifying a chair as a chair).

OK, now we're in a position to see where Meyer went astray. First, he has no idea what the photos of brain activity data mean. If you look at the photos above you will see, as Meyer's said, little or no activity in the parts of the brain associated strictly with the "cold" system, or as Meyer's nonsensically put it, the "thinking parts of their brains." You know why you don't see that activity? BECAUSE THE PHOTOS ARE OF THE ACTIVITY EXCLUSIVE TO THE CONTRADICTION CONDITION! It is the photo of the activity observed after subtracting the activity from the neutral or exculpatory conditions. You don't see activity in the "thinking parts of their brains" because that activity was subtracted out for the analysis! Anyone, and I mean anyone, who knows anything about neuroscience would have recognized that immediately. But Meyer writes an article read by thousands, and picked up by who knows how many bloggers, who were then read by who knows how many thousands more (Leiter's blog alone gets thousands of readers per day), in which he tells everyone that partisans aren't using the "thinking parts of their brains." When Westen et al. use words like "absence," they don't mean that the "thinking parts" of the brain are shut off, they mean that motivated reasoning itself doesn't engage those parts any more than they are already engaged during cold cognition (e.g., in the neutral conditions). But trust me, the thinking parts of the brain are still working just fine, and they can even override the emotional areas activated by motivated reasoning, if the facts are overwhelming. Partisans, then, are not completely irrational. They are perfectly capable of objectively reasoning about even their own candidates, if given the right incentives and information. But as happens with all of us, when their "hot" systems were activated, it biased their own reasoning processes, without them even knowing it.

Meyer argues in his article that these findings may make political persuasion impossible. It should be obvious, by now, that he's full of shit. Nothing about the Westen et al. results implies, in the least, that persuasion is impossible, even in the case of steadfast political partisans. It does imply that when strong emotions are associated with social concepts, in this case political candidates, persuasion will be more difficult. You will have to help the cold cognition system to overwhelm the hot cognition system by presenting partisans with facts that they can't rationalize. That's easier said than done, of course, but the fact that the U.S. population, once staunchly in favor of both Bush and the Iraq War, have begun to change their opinions of both in the face of overwhelming evidence, is proof positive that it is not impossible. One thing is for certain, though: it's impossible to get people who have no clue what they're talking about to stop writing about science.

One more thing. I think it's important, whenever we talk about cognitive neuroscientific studies, to note their limits. The subtraction method is full of problems, not the least of which is that just because an area doesn't increase or decrease its activity in a targeted condition relative to the condition that is subtracted from it, does not mean that those areas are not performing vital functions exclusive to the processes activated by the targeted condition. You should always take cognitive neuroscience with a salt truck-full of grains of salt. Think of the studies, and their interpretations, as interesting speculations that may be borne out by future research. But don't, I repeat do not, treat them as scientific gospel.

1Westen, D., Blagov, P.S., Harenski, K., Kilts, C., & Hamann, S. (Unpublished Manuscript). An fMRI study of motivated reasoning: Partisan political reasoning in the U.S. Presidential election.

Monday, March 20, 2006

Motivated Reasoning I: Hot Cognition

The human understanding, when it has once adopted an opinion ... draws all things else to support and agree with it. Though there may be (more) instances to be found on the other side, yet these it either neglects or despises, or else by some distinction sets aside and rejects. -F. Bacon

It's been a while since I've posted a rant about an abuse of cognitive science by the popular press or bloggers, so I figure I've got catching up to do. Fortunately, both the popular press and bloggers have given me plenty of material, by writing about research by Drew Westen on motivated reasoning in politics (a few of the dozens of contributions by bloggers, none of which I recommend, can be found here, here, here, here, here, here, and here). he gist of the stories, both in the press and in the blogs (because the blogs got all their information from the stories, of course) is that "partisans," by which they mean people who are committed to voting for Democrats or Republicans, react to negative information about their preferred candidates emotionally, rather than rationally. The common refrain is, "partisans" are irrational. What the participants in the study are actually doing, according to Westen, is using the "hot" reasoning system, a system that is not exclusive to political partisans, and is not exclusive to political reasoning. In fact, we all use it quite often, particularly in social situations. So if "partisans" are irrational, so are we, even if our irrationality doesn't show itself in politics as strongly as their's does (though I bet you could make a case that many of those bloggers, especially the one who runs the first site I linked, have trouble using the "cold" system in anything even remotely related to politics).

OK, now that I've gotten that out of my system, I can move on. Before I get to the study, or even a little background to situate it, let me say that the study, by Westen et al. has not yet been published, but instead has just recently been presented at a conference (the Annual Conference of the Society for Personality and Social Psychology). Ordinarily I don't present unpublished work (I don't think this work has even been submitted for publication!) here unless I know at least one of the researchers involved. If I do, then I feel confident, based on what I know of his or her prior work, that the unpublished work is of a high quality. In the case of this study, however, I only know a little of one author's (Westen's) work, and therefore can't vouch for its quality without it first being subjected to peer review. The research report is well written and detailed, at least, so I think it's possible to evaluate the methods, results, and conclusions. Furthermore, because there has been so much attention to the study, so much of it based in ignorance (of the study itself, and of its context), I feel compelled to write about it now, rather than six months to a year from now when it's been published and everyone's forgotten about it, but integrated the bad information about it from the press into their background knowledge. Naturally, a post on this topic will be long (I'm wordy; sue me), but the study deserves a careful analysis that includes at least the bare minimum of context. So, I'm going to divide it up into two posts, with the first post containing the background, and the second post discussing the study. Hopefully that will ease the reading load for anyone who's actually bothered to read this far (hi Mom).

Motivated Reasoning and the Hot vs. the Cold

When cognitive science was born, emotion essentially became taboo, and until recently (say the last decade), remained so, in the serious study of cognition. This also seems to have been true, for the most part, in economics, where rationality was discussed with little reference to affect. But in social psychology, emotion was often central, even if it wasn't referenced directly, in the work of people like Festinger and Heider in the 60s, and Kruglanski and Kunda in the 80s. Cognitive psychologists were so afraid of emotion that some of them, like Richard Nisbett and Lee Ross (two big names in the history of cog sci), went to great links to show that cognitive mechanisms could account for the findings that social psychologists thought were in part the result of emotion. But as the field of social cognition grew into its own, and neuroscientists like Antonio Damasio showed just how important emotion is for cognition, emotion has become fair game in cognitive scientific research. And that has led to increased attention to motivated reasoning, and its use of "hot" cognition, as opposed to strictly "rational," "cold" reasoning.

What is motivated reasoning? Kunda1 describes motivated reasoning with the following example:
[P]eople who want to believe that they will be academically successful may recall more of their past academic successes than of their failures. They may also use their world knowledge to construct new theories about how their particular personality traits may predispose them to academic success... If they succeed in accessing and constructing appropriate beliefs, they may feel justified in concluding that they will be academically successful, not realizing that they also possess knowledge that could be used to support the opposite conclusion. The biasing role of goals is thus constrained by one's ability to construct a justification for the desired conclusion: People will come to believe what they want to believe only to the extent that reason permits. Often they will be forced to acknowledge and accept undesirable conclusions, as they appear to when confronted with strong arguments for undesired or counterattitudinal positions. (p. 482)
In motivated reasoning, memory searches, interpretations of incoming information, evaluations of arguments, and even perception, are biased in such a way that we will be more likely to arrive at a desired conclusion (called a directional motivation; in the above example, the conclusion that we are likely to be academically successful is the directional motivation). The way this is achieved, in essence, is by limiting the information that is retrieved from long term memory into current working memory (the store of information that is available for current processing), thereby biasing the information available for supporting or evaluating conclusions and arguments, as well as interpreting incoming information (recall, as I've said here many times before, that incoming information is always interpreted in light of the background knowledge that it activates in memory). As Kunda notes in the quoted passage, our ability to arrive at that conclusion isn't absolute. If we're continually confronted with information that conflicts with that conclusion, we will be forced to deal with it. But as long as we can, we'll only deal with that information that is consistent with our conclusion (see, e.g., the quick discussion of the "my-side bias" in this recent post).

Motivated reasoning can, despite its limits, be quite powerful. Consider some experimental results. In some studies, participants' are asked to assess the probability of events, some of which are more desirable than others. Their ratings of the probability of an event depends on whether they found those events desirable. Desirable events are believed to be more likely to occur than undesirable events2, even when the desired event occurred less often in the observed series3. In other experiments, people's beliefs about their own introvertedness or extrovertedness vary depending on whether they have been told that introversion or extroversion leads to academic success4, and they are much better at retrieving memories of experiences of introvertedness if they believe the trait will lead to success5. People will even revise upwards their beliefs about the average person's knowledge of history if it serves to diminish the accomplishment of a high test scores on a history test by an opponent in a history trivia game6.

Very recent theories of motivated reasoning in social domains (e.g., politics) have begun to tap into the "hot cognition" system to explain motivated reasoning phenomena. In one theory7, important because it influences the perspective of Westen and his colleagues, the use of the "hot" system works something like this: First, through evaluation, social concepts become "affectively charged." This means that they develop an associated valence (positive or negative), and this valence is stored with those concepts in memory. When social concepts are activated, and retrieved from long term memory, they bring their valence with them. This activation of the concept with its valence serves to establish our "directional motivation," and thus to color our interpretation of any new information we are bringing in at the time, as well as biasing memory searches and so on. Lodge and Taber (see footnote 7) list the following situations in which we're likely to use hot cognition-driven motivated reasoning
  • One's attitudes are challenged.
  • An affective judgment is called for.
  • The consequences of being wrong are weak.
  • The judgmental task is complex.
  • "Objective" information is not readily available or the evidence is ambiguous.
  • Disconfirming evidence is not highlighted.
  • Counter-arguments come easily to mind.
  • One is distracted or under time pressure.
These situations imply that motivated reasoning is in fact our default mode of reasoning; the one that we revert to when we are threatened, when our cognitive resources are limited, or when we aren't highly motivated to make an effortful attempt to come to the objectively "right" answer. Interestingly, under this theory, motivated reasoning is automatic, relatively effortless, and likely occurs below the level of awareness. This allows for what Kunda calls the "illusion of objectivity," which is the belief that the conclusion at which we've arrived is the objectively right one, even though the processes through which we've arrived at it were biased.

Here's how this would work in political reasoning. Imagine you're a staunch G.W. Bush supporter. Your Bush concept therefore has a strong positive emotional valence associated with it. Anytime your Bush concept is activated, the associated valence will be activated, and you will be motivated to interpret any incoming information about Bush in a positive light. If potentially negative information about Bush comes to your attention, you will search for information in memory and in the environment that will help you to come to a positive interpretation of that information. Once again, that does not mean that you will ultimately be able to interpret that incoming information in a positive light. If the negative aspects of that information are overwhelming, or you are unable to retrieve information from memory that will help you interpret it in a positive light, you will be forced to interpret that information negatively. This may then cause you to update the valence associated with Bush to make it more negative (though it may still have a positive overall valence). Recent studies in the political domain have supported this picture of political reasoning8.

This is the theoretical and empirical background against which Westen and his colleagues' work exists. Before turning to that work (in the next post), though, I want to say a little bit about the neuroscience of the hot and cold systems, because their study is an imaging study. In an earlier imaging study by Goel and Dolan9, participants were given emotionally-salient and emotionally-neutral syllogisms like the following, in order to activate the hot and cold systems:
Emotionally-Salient: No doctors are criminals. .
Some doctors are rapists.
Some rapists are not criminals.

Emotionally-Neutral: Some rock stars are guitarists.
All guitarists can sing.
Some rock stars can not sing.
While they read the syllogisms, their brains were scanned using an fMRI machine. Using the subtraction method (the details and problems of which I've discussed before, here), they were able to derive the activation of various regions in each condition relative to a baseline and the activation in the other condition (e.g., for the emotionally-salient condition, the level of activation from an emotional baseline condition, along with the activation in the emotionally-neutral condition minus its neutral baseline, were subtracted to get the activation in the "hot" system).

They found that when processing the emotionally-neutral syllogisms, activation in the lateral / dorsal lateral prefrontal cortex (labeled #2 in the picture, from this website), a large area associated with "executive functions," or higher-order cognition, showed increased activation, while activation in the ventral medial prefrontal cortex (labeled #3), an area associated with emotion regulation, decreased. When processing the emotionally-salient syllogisms, activation in the ventral medial prefrontal cortex, along with the fusiform gyrus, increased, while activation in the lateral/dorsal lateral prefrontal cortex decreased. Thus, the cold system activates areas associated with logical reasoning, and suppresses activity in areas associated with emotion, while the hot system activates the areas associated with emotion, and suppresses activity in the areas associated with logical reasoning. It's important to note the word "suppresses." It's important to remember this, then: the hot system doesn't shut off the logical reasoning system, it just decreases the level of activity there, perhaps to give primacy to the activity in the areas associated with emotional processing.

That should be enough information to allow you to understand Westen's work. So I'll talk about that in the next post.

1Kunda, Z. (1990). The case for motivated reasoning. Psychological Bulletin, 108(3), 480-498.
2Arrowood, A. J. & Ross, L. (1966). Anticipated effort and subjective probability. Journal of Personality and Social Psychology, 4, 57-64.
3Irwin, F. W. & Snodgrass, J. G. (1966). Effects of independent and dependent outcomes on bets. Journal of Experimental Psychology, 71, 282-285.
4Kunda, Z. & Sanitioso, R. (1989). Motivated changes in the self-concept. Journal of Experimental Social Psychology, 25, 272-285.
5Sanitioso, R., Kunda, Z. & Fong, G. T. (1990). Motivated recruitment of autobiographical memory. Journal of Personality and Social Psychology, 59, 229-241.
6 Kunda (1990).
7Lodge, M. & Taber, C. (In Press). Three steps toward a theory of motivated political reasoning. In A. Lupia, M. McCubbins, & S.Popkin (Eds.), Elements of Political Reason: Understanding and Expanding the Limits of Rationality. London: Cambridge University Press.
8Lodge & Taber (In Press); Redlawsk, D.P., & Hubby, C.R. (2002). Hot cognition or cool consideration? Testing the effects of motivated reasoning on political decision making. Journal of Politics, 64, 1021-1044; Morriss, J.P., Squires, N.K., Taber, C.S., & Lodge, M. (In Press). The automatic activation of political attitudes: A psychological examination of the hot cognition hypothesis. Political Psychology.
9Goel, V., & Dolan, R.J. (2003). Reciprocal neural response within lateral and ventral medial prefrontal cortex during hot and cold reasoning. Neuroimagine, 20(4), 2314-2321.

Links, Links, Links

I'm not sure I've ever done a link post, but I've had the flu, and therefore have absolutely no energy whatsoever. So this is the best I can do right now. Plus, there are some really good posts by Brandon and Heo that you really should read, and I threw in a strange one by someone named Bird Dog too.

Let's start with Brandon of Siris. Partially in response to my post on thinking about evolution, and to one of the papers I cited, Brandon wrote a four-part series on essentialism: Essentialisms I, Essentialisms, Essentialisms in Biology, Essentialism and Darwin, and Intuitive Essentialism. The posts help to clarify the different senses of essentialism, as they've been used in philosophy and biology, and contain some great links (especially in the last one).

Then there's Heo Cwaeth, the best medievalist you're not reading (I know, I found that funny too!). She's started a new series titled "Medieval Women I Adore," on medieval women who, if you're like me, you've never heard of. But as the series' title suggests, Heo adores them, and after reading her posts, so do I. She has three posts so far: Æðelflæd (Aethelflaed), Chrodield and Basina, and Hilda of Whitby. I have to admit, I like Aethelflaed the most, and not only because I can't spell her name without looking. Read the post and you'll see why I think she's so cool.

Finally, I got an email earlier warning me that I would be linked at Maggie's Farm. I'd never heard of that site, so I decided to stop by and see what they were saying about the post. I found this, immediately following a call to support the academic bill of rights in the New York Assembly (I know, not a good sign):
Mixing Memory addresses the cognitive factors which they believe interfere with the supposedly benighted American population's acceptance of Evolution as Gospel. I make two points: First, as psychologists, and not physical scientists, they lack the humility which the physical scientists possess, probably because they never took Quantum Algorithms and the Fourier Transformation in college - not for lack of brain-power, but lack of interest. Second, they lack metaphysics. They are psyche-centric, which is reductionistic. I enjoy their blog regularly, but everyone has their limited view of the world, as do we, no doubt. Einstein: "Science without religion is lame; religion without science is blind." And, Yes, I do think ID is silly. But, on the other hand, I am more interested in the cognitive obstacles to connecting with God than in the cognitive obstacles to connecting with evolution. Heck - which is more important?
Huh? Maybe my fever-riddled brain has lost some of its reading comprehension skills, but if I'm not mistaken, that says that because I haven't read a nonexistent book on physics (the closest I could find to that title is a 1998 paper by Richard Jozsa in the Proceedings of the Royal Society of London), I lack humility, and therefore deigned to write a post on some of the reasons why many people have trouble understanding evolution. Forgetting for a moment that the intuitions I discussed are supposed to be universal, and therefore if I was calling anyone benighted I was calling everyone benighted, what the hell does it mean that I'm psyche-centric? Does it mean that I think thought happens in the head? Because if it does, it's true. And cognitive obstacles to "connecting with God?" I'm not sure I know what that means, either, but I have written on religious cognition before. Does that count?

I think the purpose of the post was to say that accepting evolution isn't important, and might even be a bad idea. But it's hard to get that out of what it actually says, and the attempt to undercut what I said in that post by claiming that I lack humility (duh!) and that I'm a psyche-centric reductionist (I'm certainly not a reductionist in the sense that the term is ordinarily used in the philosophy of science, but OK) certainly doesn't help. But hey, the post quotes Einstein in agreement with its position, so it must be right, right?

Friday, March 17, 2006


Blogger had some sort of major malfunction yesterday, and this blog, along with many others, was inaccessible. Hopefully the problem won't reoccur, but if you got a "forbidden" message yesterday, now you know why.

Sunday, March 12, 2006

Thinking About Evolution: Cognitive Factors That Get in the Way

My contribution to Darwin Day was pretty weak for a staunch supporter of science. Sure, I think the name is a bad idea, and want to rename it "Evolution Day," or at least something other than Darwin Day (I thought about maybe suggesting "Variation Appreciation Day," or "Hug a Mutation Day"). But objections to the name aside, I felt kind of guilty about making such a substanceless contribution to a day with what I believe are noble purposes, especially after reading (via Clark) that 53% of Americans reject evolution entirely. So I'm going to try again. This time, I'm going to approach evolution from a cognitive scientist's perspective. That means I'm going to try to answer the question, how do people think about evolution? I suspect that most of the readers of this blog realize how important a question that is, given how many people in this country reject evolution, often as a result of gross misconceptions. Education researchers certainly realize its importance, and as a result there is a large literature on evolution education, and how students understand the central concepts in evolutionary biology like natural selection, adaptation, inheritance, and so on. The short answer to the question from that literature, which I doubt will surprise anyone, is that most people don't think about evolution very well. In fact, it almost as though Dawkins' quip from The Blind Watchmaker that "it is almost as if the human brain were specifically designed to misunderstand Darwinism and to find it hard to believe" isn't that far off. In this post, I'm going to try to explain a few of the reasons why that is.

Evolution education is an interesting case for education researchers and cognitive scientists because there are so many of what you might call non-epistemic factors at play. For example, a study by Brem et al. a few years ago found that across the spectrum from creationist to evolutionist, college students tended to believe that evolution will have negative psychological and social consequences1. It's likely that for many, belief in these negative consequences influences not only their willingness to believe in evolution, but also their willingness to expose themselves to information about it, or to attempt to understand that information. There are also many social or familial factors at play. To explain differences in the developmental paths towards creationism vs. evolutionism, Margaret Evans has proposed a "model of constructive interactionism," in which "children generate intuitive beliefs about origins, both natural and intentional, while communities privilege certain beliefs and inhibit others, thus engendering diverse belief systems"2. In other words, children come to the table with certain intuitions about the origins of things (I'll discuss those intuitions in a bit), and socialization and education processes serve to encourage some of those intuitions while de-emphasizing others. Thus, children in strong creationist families will have their intuitions that are directly opposed to evolution encouraged, making the job of science educators even more difficult. In this post, I'm going to describe three of of the intuitions and biases that are directly relevant to how children and adults think about evolution, because I find them to be the most interesting.

Intuitive Theists

There is a growing body of evidence indicating that children are inclined to view both artifacts and natural kinds (biological and non-biological) as existing for a purpose, and to believe that they were intentionally created for that purpose. Here is Deborah Kelemen describing some of the research indicating children's inclination to believe that natural kinds have a purpose3:
Consistent with the view that from very early on, teleological assumptions constrain our reasoning about living things, studies have found that young children attend to shared functional adaptation rather than shared overall appearance (or category membership) when generalizing behaviors to novel animals (Kelemen et al., 2003a), judge whether biological properties are heritable based on their functional consequences rather than their origin and explain body properties by reference to their self-serving functions not their physical-mechanical cause.
The objects to which children will attribute a purpose range from animal parts (e.g., legs are for walking) to whole animals (lions exist "to go in the zoo"), and even non-biological kinds (clouds exist to make rain). In addition, when asked whether someone created the first of a particular item, children are likely to answer yes for all three kinds of objects (artifacts, biological kinds, and non-biological natural kinds)4. It's understandable, then, why evolution should be difficult to teach to children: it is counterintuitive. Both the non-teleological aspects of evolutionary explanations of the origins of biological kinds, and the lack of a need for an intelligent designer go against children's natural view of things.

But the story is actually somewhat worse for evolution than intuitions about purpose and intentional creation indicate. While evolution involves non-teleological processes, teleological language is still pretty common in discussions of evolution (even Darwin used it), and many adults who believe in various intelligent design philosophies insist that the intelligent design position is not inconsistent with evolutionary biology. But children's intuitions may be more specific than simply inferring teleology and purposeful creation. They may actually be creationists, at least at certain ages. Margaret Evans has explored the beliefs of children in both fundamentalist Christian and non-fundamentalist households, and found an interesting, and for educators, somewhat disturbing pattern5. In her study, children under the age of 8 in fundamentalist households tended to be strict creationists: they believed that a non-human intelligent entity (God) created all animals as they are now, while children under the age of 8 in non-fundamentalist homes held beliefs that Evans describes as a mixture of creationism and "generationist" origins (such as "the first robins came from eggs); between the ages of 8 and 10 years, children were strict creationists, regardless of the type of household; and from 11 on, children in fundamentalist households tended to be strict creationists, while children in non-fundamentalist homes tended to be evolutionists. Thus it appears that education can, in older children, overcome creationist intuitions, but only if that education is consistent (or at least not inconsistent) with what children are being taught in the home.

The work of Kelemen and Evans helps to explain why evolution has had such a hard time becoming widely accepted by the general public. From an early age, our intuitions run counter to evolutionary science, and unless children live in homes where evolution is not seen as being counter to the belief systems of their parents, they will not let go of those intuitions, even when they are taught about evolution in school. Those children will then go on to privilege those same intuitions in their children, and so on, leading to generation after generation of individuals who, by the time they are college-aged, will find it very difficult to accept any evolutionary teachings.

Intuitive Essentialists

In what's now a classic paper, Medin and Ortony6 argued that humans may be intuitive essentialists. They called this position "psychological essentialism," and there is a growing body of evidence indicating that they were right. We are essentialists, especially about natural kinds, and biological kinds in particular, from a very young age. It may not seem so at first, but this fact could have very important implications for evolution education, and the willingness, perhaps even the ability, of many people to accept evolution as an explanation of biological origins.

Here is how Gelman and Markman expressed what later became the psychological essentialism position7:
Natural kinds are categories of objects and substances that are found in nature (e.g., tiger, water, cactus)... natural kind terms capture regularities in nature that go beyond intuitive similarity... Natural kinds have a deep, nonobvious basis; perceptual features, though useful for identifying members of a category, do not always serve to define the category. For example, "fool's gold" looks just like gold to most people, yet we accept the statement of an expert that it is not gold... Because natural kinds capture theory-based properties rather than superficial features, some of the properties that were originally used to pick out category members can be violated, but we still agree the object is a member of the kind if there is reason to believe that "deeper," more explanatory properties still hold. (p. 1532)
In other words, people believe that natural kinds have an underlying, unseen essence that makes them what they are, and that while this essence is likely associated in some causal fashion with the surface features that we usually use to classify an instance of a kind, the essence remains the same regardless of whether the surface features change. For biological kinds, people (including young children) believe that origins (who the parents were) determine the essence of an individual. Thus, when an animal born as a raccoon, to raccoon parents, is painted too look like a skunk, and has a sack containing a stinky substance surgically implanted, children still call it a raccoon8. This belief has implications for how people make inferences about biological kinds, including inferences about origins. For example, in a study with adults, participants heard a story about a fictitious animal, called a "sorp," that has all the prototypical features of a bird (feathers, makes nests, etc.). In the story, the "sorp" falls into a vat of toxic waste, and all of its perceptual features change: its feathers are gone, and it now has wings that look like insect wings, has an insect-like exoskeleton, and so on. It now looks like an insect, not a bird. As the story moves along, the insect-like sorp mates with a normal sorp. The participants were then asked whether the offspring of the changed and normal couple will have insect-like or bird-like offspring. They overwhelmingly indicated that the offspring would be more bird-like9.

In a paper published in this month's issue of Cognitive Psychology10, Andrew Shtulman argues that essentialist thinking may have implications for how people understand evolution. He writes:
Applied to the study of biological adaptation, essentialism led early evolutionary theorists to commit what Gould (1996) calls the “fallacy of reified variation,” or the tendency “to abstract a single ideal or average as the essence of a system and to devalue or ignore variation among the individuals that constitute the full population” (p. 40). These theorists construed evolution as the process by which a species’ essence is transformed over time, and they proposed a variety of essence-transformation mechanisms, including the inheritance of acquired traits (Lamarck, 1809), the unfolding of a preprogrammed design (Chambers, 1844), the recapitulation of ontogeny (Haeckel, 1876), the acceleration of growth (Cope, 1896), the chemical structure of protoplasm (Berg, 1926), the lawful properties of organic matter (Eimer, 1898), the intentional properties of intelligent systems (Butler, 1916), and an élan vital (Bergson, 1911). (pp. 172-173)
Shtulman lumps these positions together under the heading of "transformationalism." Darwin, Shtulman argues, was so important because he was able to overcome the intuitive essentialist thinking that dominated the work of these and many other natural scientists, and thus overcome transformationalism. His theory embodies what Shtulman calls variationism, which he describes as (referencing the figure below):
First, chance mutations and sexual recombinations create indidifferencessrences among members of the same species (depicted in the left handfthand panel of Fig. 1 as arrows between parents and offspring of different colors). Second, some of these individual differences are retained and others are eliminated on the basis of their utility to survival and reproduction (depicted by circles around the few organisms that produce offspring.
Shtulman illustrates the differences between the two positions with this diagram:

Notice how in the transformationalist diagram, the color of some of the moths changes slowly over generations (presumably to a more and more adaptive color), while in the variationist diagram, one-time mutations create variability in the population of moths that is passed on from generation to generation, with the new color becoming more common in the population because it is more adaptive.

Most of us, unfortunately, are not Darwins, and overcoming such deeply ingrained intuitive biases may not come easy to us, even after years of science education. Shtulman presents data in his paper showing that both high school and college students (though not evolutionary biologists), tend to consistently give transformationalist answers to questions about origins and adaptation. Thus, it appears that in a very important way, our intuitive essentialist beliefs about biological kinds make it difficult for us to understand how evolution works.

The Value of Beliefs

Many factors man contribute to the value of particular beliefs. Howevrecentecents study by Jesse Preston and Nicholas Epley11 demonstrates two factors that may be of particular importance in the relationship between evolution and some religious beliefs (e.g., those held by 53% of the American public, according to the survey linked above). They showed that when people are asked to explain things with a belief, the perceived value of that belief goes up, whereas when people are asked to explain a belief, the perceived value goes down. They interpret this as showing that the value of a belief is, at least in part, determined by its position in a causal or explanatory sequence. If the belief explains a lot of other facts and beliefs, then it is valuable, whereas if it is explained by other facts or beliefs, it becomes less valuable. In one of their experiments, they explicitly looked at what they called "cherished beliefs," in this case, beliefs about God. Participants were divided into four groups. Two groups were asked to list things that belief in God could explain, with one group asked to give three and one ten things. The other two groups were asked to list either 3 or 10 observations that could explain God's "behavior." Overall, participants who believed in God (self-reported atheists were excluded) had a difficult time listing observations that could explain God's behavior, but when they did, whether they listed 3 or 10, their ratings of their belief in God were lower than the participants in the applications conditions. Preston and Epley argue that the difficulty participants had in providing observations that explain God's behavior may be a result of the fact that people have a hard time coming up with explanations for highly valued beliefs, because these explanations would devalue beliefseleifs.

The implications of these findings for evolution education should be obvious. For many who believe that God produce biological kinds, and humans specifically, in their present form, an alternative explanation, even if it is possible to say that it was the work of God, will serve to devalue that belief, by relegating it to a lower position in the explanatory system. Thus, the very nature of our relationship to beliefs we hold valuable may make evolution education more difficult, particularly for people raised in in fundamentalist traditions.


So that's my contribution. I've presented three factors that make the job of biology teachers more difficult when they're trying to teach evolution, either to children or adults.
  1. Intuitive theism, in which our intuitions lead us to make design inferences about complex kinds or under conditions of uncertainty; intuitions that can be reinforced culturally to an extent that it may be almost impossible to overcome them by the time we reach adulthood.
  2. Intuitive essentialism, which causes us to believe that biological kinds have hidden internal essences which determine what they are, how they will behave, and what features they should have, and which may make us interpret evidence of adaptation in transformationalist, rather than Darwinian/modern biological varationist terms.
  3. The role of explanatory power in determining the value of beliefs, and the fact that we may resist explaining our most cherished beliefs in order to avoid devaluing them.
There are probably more cognitive factors that make understanding and believing modern biological accounts of evolution difficult for many people, but these three together, or alone, can pose significant challenges, and each should be in the backs of educators' minds when teaching people about evolution. To be honest, I'm not sure how to overcome the third factor. As recent world events have shown, when beliefs are as cherished as religious beliefs are for many, defense of those beliefs against any perceived threat can be extremely passionate, even violent. If many people really do perceive that the potential explanatory power of evolution could pose a threat to the value of their religious beliefs about the origins of man, beliefs that they cherish deeply, it's unlikely that any amount of education will overcome their defensiveness. But the prospects of overcoming the first two factors do seem promising. Clearly many biologists (including three who completed the questionnaire in Shtulman's study were able to overcome their transformationalisttnalist bias caused by their intuitive essentialism (see also this paper, by Evans and her colleagues, on one technique for overcoming essentialist biases in children), and Evans' work on intuitive theism indicates that, as long as parents aren't encouraging theistic intuitions, thus making us skeptical or resistant to evolutionary accounts of origins, our seemingly innate tendency to make design inferences can be overcome through education.

1Brem, S.K., Ranney, M., & Schind, J. (2002). Perceived consequences of evolution: College students perceived negative personal and social impact in evolutionary theory. Science Education, 87(2), 181-206.
2Evans, E.M. (2001). Cognitive and contextual factors in the emergence of diverse belief systems: creation versus evolution. Cognitive Psychology, 42(3), 217-266.
3Kelemen, D. (2004). Are children 'intuitive theists'?: Reasoning about purpose and design in nature. Psychological Science, 15(5), 295-301.
4Kelemen, D., & DiYanni, C. (2005). Intuitions about origins: Purpose and intelligent design in children's reasoning about nature. Journal of Cognition and Development, 6(1), 3-31.
5Evans, E. M. (2001). Cognitive and contextual factors in the emergence of diverse belief systems: Creation versus evolution. Cognitive Psychology, 42, 217-266.
6Medin, D. L., & Ortony, A. (1989). Psychological essentialism. In S. Vosniadou & A. Ortony (Eds.), Similarity and Analogical Reasoning, Cambridge, 179Ã?–195 .
7Gelman, S.A., & Markman, M. (1986). Young children's inductions from natural kinds: The role of categories and appearances. Child Development, 58, 1532-1541.
8Keil, F.C. (1989). Concepts, Kinds, and Cognitive Development. Cambridge, MA: MIT Press.
9Rips, L. J. (1989). Similarity, typicality, and categorization. In S. Vosniadou & A. Ortony (Eds.), Similarity and Analogical Reasoning. Cambridge, England: Cambridge University Press, pp. 21-59.
10Shtulman, A. (2006). Qualitative differences between naïve and scientific theories of evolution. Cognitive Psychology, 52, 170-194.
11Preston, J., & Epley, N. (2005). Explanations versus applications: The explanatory power of valuable beliefs. Psychological Science, 18, 826-832.

Friday, March 10, 2006

Koufax Voting

I'd completely forgotten that I'd been nominated for a Koufax Award until I noticed someone coming from that page tonight. Voting is open. As promised, I voted for Real Climate. I said it before, and I'll say it again, those guys are seriously smart. I suggest you all go vote for one of the science blogs. And if you're doing things just because I told you to, then you should vote for either Real Climate or a cognitive science blog. There are two, and since I really don't feel like I'm at all in the same category as most of the blogs on that list, you should vote for the other one (Cognitive Daily).

Cynical from a Young Age

The research mentioned in yesterday's post shows that children may display altruistic behavior at a much earlier age than previously thought. To continue with that theme, I thought I'd post on some research by Candice Mills and Frank Keil1 showing that children may display cynicism at a much earlier age than previously thought, as well. In both lines of research, interesting aspects of children's theory-of-mind are demonstrated. And in both cases, we may have to change the way we think about children's social cognition. Children, it turns out, may be a bit more sophisticated than we usually give them credit.

Historically, young children have been thought to be extremely naive and gullible, in part because people thought they had to be. Here's how Richard Dawkins put the traditional position2:
When you are pre-programmed to absorb useful information at a high rate, it is hard to shut out pernicious or damaging information at the same time. With so many mindbytes to be downloaded, so many mental codons to be replicated, it is no wonder that child brains are gullible, open to almost any suggestion, vulnerable to subversion, easy prey to Moonies, Scientologists and nuns. Like immune-deficient patients, children are wide open to mental infections that adults might brush off without effort. (pp. 13-14)
But we already know that children are much better at distinguishing fantasy from reality than most had previously thought. And in two experiments, Mill and Keil have shown that they're also pretty cynical when deciding whether people might be telling the truth, when they might not, and why they might or might not be telling the truth.

In the first experiment, participants in three age groups (kindergarten, second grade, and fourth grade) were trained on a 5-point rating scale (described below), and then read twelve short stories (about four sentences long). There were four different kinds of stories, and each child heard three of each. The first two types of stories involved a situation (e.g., a race) in which, if the main characterachievedd a certain outcome, he or she would win a prize. Thus, in these stories the main character had a specific personal interest, namely winning the prize. In one version of each of these stories (with self-interest version), the main character stated that he or she hadachievedd the outcome required to win a prize. In this case, then, the character's claims were consistent with his or her self-interest. In the other version of these stories (against self-interest version), the character stated that he or she had notachievedd the required outcome. Thus in this version the characters' statements were against his or her personal interests. The other two conditions were included as controls. In these stories, the outcome was known. In the true version of the story, the character correctly stated that he or she had won the prize. In the false version, the character incorrectly states that he or she had not won the prize. After each story, the children were asked to rate how much they believed the character on a 1 to 5 scale, with one indicating that they don't believe the character at all, and 5 indicating that they believe him or her completely.

As we would expect, for all ages, children's ratings of their belief of the character in the true version were much higher than their ratings of their belief of the character in the false version. This indicates both that they understand how to use the ratings, and that they are not simply more likely to disbelieve someone who says he or she won, or to believe someone who says he or she lost. The interesting results, however, occurred for the with self-interest and against self-interest versions. Kindergarten children were significantly more likely to believe that the characters were telling the truth in the with self-interest condition. Second and fourth graders, however, were significantly more likely to believe that the characters were telling the truth in the against self-interest condition. This is the way adults tend to answer in similar experiments, also3. Thus, the data from this first experiment indicates that between kindergarten age and second grade, children began to develop adult-like cynicism.

In the second experiment, children from the same three age groups, along with a group of six graders, were read stories similar to those from the first experiment. In each of these stories (six in all), the characters made incorrect statements. In half of the stories, the incorrect statements were consistent with the personal interests of the character, and in the other half, they were against those interests. The children were then asked to indicate what they thought was the best explanation for the incorrect statement: the character was lying, the character was biased, or the character made a mistake. The results were as follows: for kindergarten, second grade, and fourth grade children, incorrectstatementss that were consistent with the character's self-interest were most often explained as lies, while incorrect statements that were inconsistent withtheh character's self-interest were most often explained as mistakes. Sixth graders gave similar explanations, except that they listed bias as an explanation for incorrect statements consistent with the character's self-interest about as often as they listed lying. Mill and Keil explain this small difference between the younger children and the six graders by noting that in the literature, young children have been shown to underestimate or ignore the role of interpretation in people's thinking4.

Thus, children as young as 7 (second graders) believe that people's self-interest affects their honesty, and children as young as 5 kindergartenerss) believe that when people make incorrect statements that are consistent with their self-interests, they probably did so intentionally (or because they are biased, for sixth graders). Young children appear to be cynics pretty early on, then. By the second grade, they're approaching full-fledged adult cynicism, and are not the gullible information-sponges that many believe them to be.

1Mills, C., & Keil, F.C. (2005) The Development of Cynicism. Psychological Science, 16, 385-390.
2Dawkins, R. (1993). Viruses of the mind. In B. Dahlbom (Ed.), Dennett and His Critics: Demystifying Mind. Oxford, England:
Blackwell, pp. 13–27, as quoted in Mills & Keil (2005).
3Murukutla, N., &Armor, D.A. (2003). Illusions of objectivity in the dispute between India and Pakistan over Kashmir. Unpublished
manuscript, Yale University, New Haven, CT.
4Carpendale, J.I., & Chandler, M.J. (1996). On the distinction between false belief understanding and subscribing to an interpretive theory of mind. Child Development, 67, 1686–1706.

Thursday, March 09, 2006

Human Infant and Chimpanzee Altruism

Some of you may have read in the popular press about the study recently published in Science, by Felix Warneken and our old friend Michael Tomasello, in which both human infants (18 months) and young chimpanzees displayed altruistic behavior. The display of altruistic behavior is interesting, but what I find even more interesting is the level of theory of mind capabilities displayed by the young chimps. Here's how the experiments work (there are a few variations):

An experimenter is holding or trying to do something with an object (e.g., a marker or a sponge), while the infant or chimp is watching. At some point, the experimenter drops the object out of his reach (or the objects he needs to complete his task are out of reach), and makes a big deal of trying to reach it but failing. The infants and chimps then go to get the object and bring it back to the experimenter. If the experimenter drops the object in such a way that it was clear that he did it on purpose, however, neither the child or the chimp tended to help him retrieve it.

Unfortunately, the paper is only accessible with a subscription, so I can't link you to it (the reference is below, if you have a subscription or want to take a trip to the library). However, at Warneken's website, you can actually view clips from the experiments with both infants and chimps. So you can see how these things work.

Warneken, F. & Tomasello, M. (2006). Altruistic helping in human infants and young chimpanzees. Science, 311(5765), 1301-1303.