Autism: difference or disease?

There is an article in Wired Magazine arguing that autism is not a disease, but just a matter of difference and neurodiversity. It argues that the myth that almost 75% of Autistics are mentally retarded does not stand to scrutiny, but is perpetuated as we use measures of intelligence that are highly verbal in nature.

A cornerstone of this new approach — call it the difference model — is that past research about autistic intelligence is flawed, perhaps catastrophically so, because the instruments used to measure intelligence are bogus.

Mike Merzenich, a professor of neuroscience at UC San Francisco, says the notion that 75 percent of autistic people are mentally retarded is "incredibly wrong and destructive." He has worked with a number of autistic children, many of whom are nonverbal and would have been plunked into the low-functioning category. "We label them as retarded because they can't express what they know," and then, as they grow older, we accept that they "can't do much beyond sit in the back of a warehouse somewhere and stuff letters in envelopes."

The article focuses on the work of Dr. Mottron, who believes in the difference model and has researched on the strengths that Autistics may exhibit.

By the mid-1990s, Mottron was a faculty member at the University of Montreal, where he began publishing papers on "atypicalities of perception" in autistic subjects. When performing certain mental tasks — especially when tapping visual, spatial, and auditory functions — autistics have shown superior performance compared with neurotypicals. Call it the upside of autism. Dozens of studies — Mottron's and others — have demonstrated that people with autism spectrum disorder have a number of strengths: a higher prevalence of perfect pitch, enhanced ability with 3-D drawing and pattern recognition, more accurate graphic recall, and various superior memory skills.

The article goes on to discuss a recent paper that showed that autistics have the same level of intelligence- only that their intelligence is of a different kind: non-verbal.

Last summer, the peer-reviewed journal Psychological Science published a study titled "The Level and Nature of Autistic Intelligence." The lead author was Michelle Dawson. The paper argues that autistic smarts have been underestimated because the tools for assessing intelligence depend on techniques ill-suited to autistics. The researchers administered two different intelligence tests to 51 children and adults diagnosed with autism and to 43 non-autistic children and adults.

The first test, known as the Wechsler Intelligence Scale, has helped solidify the notion of peaks of ability amid otherwise pervasive mental retardation among autistics. The other test is Raven's Progressive Matrices, which requires neither a race against the clock nor a proctor breathing down your neck. The Raven is considered as reliable as the Wechsler, but the Wechsler is far more commonly used. Perhaps that's because it requires less effort for the average test taker. Raven measures abstract reasoning — "effortful" operations like spotting patterns or solving geometric puzzles. In contrast, much of the Wechsler assesses crystallized skills like acquired vocabulary, making correct change, or knowing that milk goes in the fridge and cereal in the cupboard — learned information that most people intuit or recall almost automatically.

What the researchers found was that while non-autistic subjects scored just about the same — a little above average — on both tests, the autistic group scored much better on the Raven. Two individuals' scores swung from the mentally retarded range to the 94th percentile. More significantly, the subset of autistic children in the study scored roughly 30 percentile points higher on the Raven than they did on the more language-dependent Wechsler, pulling all but a couple of them out of the range for mental retardation.

I, myself, have been arguing for a continuum model of abilities with Autism at one end and schizophrenia at the other end of cognitive thinking and sensory processing styles; so I am sympathetic to the above account of a difference model.

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Encephalon: New Season arrives

The new season of Encephalon has started at the Sharpbrains blog and this time addresses 24 questions to the US presidential candidates ala science debate 2008!

There are a variety of good posts there including discussions of free will and whether a trauma is relevant for PTSD ?

Have a look and contribute to further editions!!

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Encephalon: second innings to start with a bang!

Alvaro, at the Sharpbrains , has taken over the ownership of the brain sciences blog carnival Encephalon, and would be opening the second innings on the 18th of feb. He has just posted an announcement on Sharpbrains as to how to contribute. The rules and procedure remain the same. You need to send a mail to encephalonDOThostATgmailDOTcom (convert CAPS to special chars ).

I'm hopeful that we are going to see some interesting posts via this carnival. If you have written a neurosciences/ psychology related post in the past few weeks , do send them to the carnival.

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The Rat Park: Addiction and Environmental factors

I recently came across an article in the Walrus Magazine on the Rat Park. Basically a rat park is providing an enriched environment to the rats (both physical and social) as compared to the skinner box and then letting them self-administer the drugs of abuse like morphine. It was found that rats were not prone to addiction to these habit forming drugs , if they lived in an enriched environment.

The problem with the Skinner box experiments, Alexander and his co-researchers suspected, was the box itself. To test that hypothesis, Alexander built an Eden for rats. Rat Park was a plywood enclosure the size of 200 standard cages. There were cedar shavings, boxes, tin cans for hiding and nesting, poles for climbing, and plenty of food. Most important, because rats live in colonies, Rat Park housed sixteen to twenty animals of both sexes.

Rats in Rat Park and control animals in standard laboratory cages had access to two water bottles, one filled with plain water and the other with morphine-laced water. The denizens of Rat Park overwhelmingly preferred plain water to morphine (the test produced statistical confidence levels of over 99.9 percent). Even when Alexander tried to seduce his rats by sweetening the morphine, the ones in Rat Park drank far less than the ones in cages. Only when he added naloxone, which eliminates morphine’s narcotic effects, did the rats in Rat Park start drinking from the water-sugar-morphine bottle. They wanted the sweet water, but not if it made them high.

In a variation he calls “Kicking the Habit,” Alexander gave rats in both environments nothing but morphine-laced water for fifty-seven days, until they were physically dependent on the drug. But as soon as they had a choice between plain water and morphine, the animals in Rat Park switched to plain water more often than the caged rats did, voluntarily putting themselves through the discomfort of withdrawal to do so.

Rat Park showed that a rat’s environment, not the availability of drugs, leads to dependence. In a normal setting, a narcotic is an impediment to what rats typically do: fight, play, forage, mate. But a caged rat can’t do those things. It’s no surprise that a distressed animal with access to narcotics would use them to seek relief.

The article then goes on to address some of the politics behind funding and how Alexander could not secure funding and how he later tried to study the same phenomenon in humans.

Unable to secure funding, Alexander conducted most of his research in the library, where he gathered a mountain of evidence. A survey of Ontario households in 1987, for example, suggested that 95 percent of those who had ever tried cocaine were using it less than once a month. A 1990 survey conducted in the US found that crack cocaine, “the most addictive drug on earth,” was addicting only one user in a hundred. “Naturally, because scholars are scrupulous, I’ve had to try it [morphine] myself,” Alexander says. “It’s no big deal. You’re visibly lightened of pain and anxiety, and that’s mildly pleasant.” But he didn’t experience any urge to try it again. “I just wasn’t interested, and that’s the typical response.”

Then there are the thousands of American soldiers who became heroin addicts during the Vietnam War. In an unrivalled demonstration of the effect of setting, a 1975 survey found that 88 percent of them simply stopped using the drug when they left the war zone. Their experience has been recreated by millions of hospital patients who have received (and become physically dependent on) morphine for severe pain. If opioids are all they’re reputed to be, this practice should have produced legions of addicts. Instead, as researchers have discovered, once patients are no longer in physical distress, they can’t wait to quit the drug, go through the withdrawal period, and get on with their lives. It’s Rat Park’s “Kicking the Habit” experiment carried out on humans, with the same result.

In my view this is an important funding, that has been kept suppressed for a long time, but whose time has come now. We all know the beneficial effects of enriched environments and the harmful effects of stress (even social stress like placed in a lower social dominance hierarchy ) . In a similar experiment with primates it was found that those who were at the top of the social dominance hierarchy did not become addicted while those at the lowest level of hierarchy became addicting to stuff like cocaine and heroin.

Dominant animals had more D2 [dopamine receptor] activity than subordinates, but that was a consequence of their dominance, and not its cause [emphasis added]. Regardless of their D2 activity when kept individually, monkeys that became subordinate showed little change in their PET responses after they had been put into company. In the animals that became dominant, by contrast, D2 activity increased significantly… Like D2 activity, cocaine use was related to social status. Dominant animals found a preferred level, then stuck to it. Subordinates, though, seemed to need bigger and bigger fixes as time went on. That is a classic symptom of addiction… Propensity to addiction, in other words, is not a predisposition of the individual, but the result of social context.

All these data merit a rethink of addiction as a purely biological phenomenon and implores us to take a more environmental approach.

Hat tip: Neuroanthropology blog

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Autism / Psychosis: Agency and Joint Attention

A recent study by Tomosello's group indicates that children with autism, can help a stranger pick a pen (and thus can apparently infer goal and intentional states of others), but cannot indulge in co-operative behavior that may involve shared goals and shared attention.

As per Translating Autism blog:

This fresh-off-the-press article comes to us from Dr. Michael Tomasello’s group at the Max Planck institute in Germany. The authors present the results of two studies looking at helping and cooperation in children with autism. The first study compared 15 children with ASD (14 with Autism and 1 with PDD-NOS) with 15 children with other non-ASD developmental delays (40 months of age average). During this study the children were place in situations that either called for helping behaviors (such as picking up a pen that the researcher dropped and could not reach) or a similar situation that did not necessarily call for helping behaviors (such as when the researcher threw the pen on purpose and did not attempt to pick it up). Both groups (children with Autism and children with other developmental delays) showed more helping behaviors when placed in the situation that called for such behaviors. That is, when the experimenter was “trying” to reach an out-of-reach object, both groups were more likely to help than when the experimenter was not trying to reach for the object. The authors concluded that these behaviors showed that both groups understood the adult’s goals and were motivated to help her. In the second study, the same children were placed in situations that called for “cooperative” behaviors, such as a task requiring them to work with the researcher by simultaneously pulling at two cylinders to reach a toy. The results showed that children with autism were less likely than kids with other developmental delays to successfully complete the cooperation tasks. Furthermore, the children with autism were less likely to initiate additional attempts to complete the task when the task was interrupted. The authors concluded that, at least at this developmental period, children with autism seem to understand the social components of situations that call for “helping” behaviors and engage in helping behaviors, but only when such help does not require interpersonal cooperation. However, when cooperation is required to complete the task, these children are less likely to correctly engage with another partner, possibly because the unique “shared” component of cooperation. That is, cooperation requires shared goals, shared attention, and a shared plan of action, processes that seem to be affected in children with autism.

Here is the abstract of the Tomosello paper:

Helping and cooperation are central to human social life. Here, we report two studies investigating these social behaviors in children with autism and children with developmental delay. In the first study, both groups of children helped the experimenter attain her goals. In the second study, both groups of children cooperated with an adult, but fewer children with autism performed the tasks successfully. When the adult stopped interacting at a certain moment, children with autism produced fewer attempts to re-engage her, possibly indicating that they had not formed a shared goal/shared intentions with her. These results are discussed in terms of the prerequisite cognitive and motivational skills and propensities underlying social behavior

From the above it is clear that children with Autism lack shared attention: a pre-requisite for language and their language impediments may also be due to this fact. If we contrast this with Schizophrenia/ Psychosis ( and assuming they are at opposite ends) it is not hard to see that with too much shared goals/ intentions/ attention, one may likely confuse between one's own goals and those of others and in a joint scenario be more susceptible to delusions of control/ though insertion, wherein the shared space has become so vast that one seems to be controlled by the other or intruded by the other. thus , I propose that children susceptible to psychosis should show enhanced cooperating behavior indicating an overactive shared goals/ attention module.

Another interesting study I would like to discuss is the recent reporting of a dysfunctional 'self' module/model in a Trust game as compared to the 'other' module/ model. Here is how the Science Daily describes the Trust game that was used in the game.

In the trust game, one player receives an amount of money and then sends whatever amount he or she wants to the other player via computer message. The amount sent is tripled and the player at the other end then decides how much of the tripled amount to send back. The game has several rounds.

The 'self' module was identified as the brain areas (cingulate cortex) involved when making the decision to share the initial amount of money with another person. The 'other' module was defined as network region activated when the decision of the other player was revealed to them.

It was found that autistics showed lowered activity in the 'self' module. The authors construe this as evidence that they have a defective self concept.

"To have a good self concept, you have to be able to decide if the shared outcome is due to the other person or due to you," said Montague. "If people can't see themselves as a distinct entities at deeper levels, there is a disconnect."

I beg to differ. In my view the findings can be explained using the joint attention / goal/ outcome defect outlined above. Although I believe that their explanation that people with autism may have a diminished sense of self or Agency also makes intuitive sense and I have argued the same previously. I contrast that with the Psychotic case where one attributes too much agency- even to inanimate objects or animals for example. However, in this case a more parsimonious explanation can be that the autistics were not able to model the others goal as their own (the familiar simulation argument) and could not indulged in joint goal intention and thus failed to optimally use the 'self' module i/e failed to take whatever actions were needed for a co-operative and trustful behavior .

The Friths adequately sum that up:

In a preview in the journal Neuron, Chris and Uta Frith wrote, "This is an exciting result because it suggests that some mechanisms of social interaction are intact in these high-functioning cases. What is the critical difference between the self phase and the other phase? We believe that the simple distinction of self versus other is not adequate. "It involves higher-order mentalizing: you care what another person thinks of you, and even further, you care that the other person trusts you. You would not do this when playing against a computer. In autism there is no difference," wrote the Friths, who are at University College London.

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Russsinas have a richer discriminative experience of light and dark blue qualia

I have blogged extensively earlier regarding language, color and the sapir -whorf hypothesis. My position in the above is clear, I lean towards the sapir-whorf hypothesis and a mild form of linguistic determinism. Now a new study (which I had missed earlier) by Lera Boroditsky presents further corroborating evidence that language influences even such basic functions as color perception. As per their 2007 PNAS paper, Russians are better (more speedily) able to distinguish between the light blue and dark blue color in an objective color perception task, thanks to the fact that Russian has a different color term for dark blue and a different one for the light blue. It is an excellent paper and I present some excerpts from the introduction:

Different languages divide color space differently. For example,the English term ‘‘blue’’ can be used to describe all of the colors in Fig. 1. Unlike English, Russian makes an obligatory distinction between lighter blues (‘‘goluboy’’) and darker blues (‘‘siniy’’). Like other basic color words, ‘‘siniy’’ and ‘‘goluboy’’ tend to be learned early by Russian children (1) and share many of the usage and behavioral properties of other basic color words (2). There is no single generic word for ‘‘blue’’ in Russian that can be used to describe all of the colors in Fig. 1 (nor to adequately translate the title of this work from English to Russian). Does this difference between languages lead to differences in how people discriminate colors?

The question of cross-linguistic differences in color perception has a long and venerable history (e.g., refs. 3–14) and has been a cornerstone issue in the debate on whether and how much language shapes thinking (15). Previous studies have found cross-linguistic differences in subjective color similarity judgments and color confusability in memory (4, 5, 10, 12, 16). For example, if two colors are called by the same name in a language, speakers of that language will judge the two colors to be more similar and will be more likely to confuse them in memory compared with people whose language assigns different names to the two colors. These cross-linguistic differences develop early in children, and their emergence has been shown to coincide with the acquisition of color terms (17). Further, cross-linguistic differences in similarity judgments and recognition memory can be disrupted by direct verbal interference (13, 18) or by indirectly preventing subjects from using their normal naming strategies (10), suggesting that linguistic representations are involved online in these kinds of color judgments.

Because previous cross-linguistic comparisons have relied on memory procedures or subjective judgments, the question of whether language affects objective color discrimination performance has remained. Studies testing only color memory leave open the possibility that, when subjects make perceptual discriminations among stimuli that can all be viewed at the same time, language may have no influence. In studies measuring subjective similarity, it is possible that any language-congruent bias results from a conscious, strategic decision on the part of the subject (19). Thus, such methods leave open the question of whether subjects’ normal ability to discriminate colors in an objective procedure is altered by language.

Here we measure color discrimination performance in two language groups in a simple, objective, perceptual task. Subjects were simultaneously shown three color squares arranged in a triad (see Fig. 1) and were asked to say which of the bottom two color squares was perceptually identical to the square on top.

This design combined the advantages of previous tasks in a way that allowed us to test for the effects of language on color perception in an objective task, with an implicit measure and minimal memory demands.

First, the task was objective in that subjects were asked to provide the correct answer to an unambiguous question, which they did with high accuracy. This feature of the design addressed the possibility that subjects rely only on linguistic representations when faced with an ambiguous task that requires a subjective judgment. If linguistic representations are only used to make subjective judgments in ambiguous tasks, then effects of language should not show up in an objective unambiguous task with a clear correct answer.

Second, all stimuli involved in a perceptual decision (in this case, the three color squares) were present on the screen simultaneously and remained in full view until the subjects responded. This allowed subjects to make their decisions in the presence of the perceptual stimulus and with minimal memory demands.

Finally, we used the implicit measure of reaction time, a subtle aspect of behavior that subjects do not generally modulate explicitly. Although subjects may decide to bias their decisions in choosing between two options in an ambiguous task, it is unlikely that they explicitly decide to take a little longer in responding in some trials than in others.

In summary, this design allowed us to test subjects’ discrimination performance of a simple, objective perceptual task. Further, by asking subjects to perform these perceptual discriminations with and without verbal interference, we are able to ask whether any cross-linguistic differences in color discrimination depend on the online involvement of language in the course of the task.

The questions asked here are as follows. Are there crosslinguistic differences in color discrimination even for simple, objective, perceptual discrimination tasks? If so, do these differences depend on the online involvement of language? Previous studies with English speakers have demonstrated that verbal interference changes English speakers’ performance in speeded color discrimination (21) and in visual searching (22, 23) across the English blue/green boundary. If a color boundary is present in one language but not another, will the two language groups differ in their perceptual discrimination performance across that boundary? Further, will verbal interference affect only the performance of the language group that makes this linguistic distinction?

They then go on to discuss their experimental setup (which I recommend you go and read). Finally they present their findings:

We found that Russian speakers were faster to discriminate two colors if they fell into different linguistic categories in Russian (one siniy and the other goluboy) than if the two colors were from the same category (both siniy or both goluboy). This category advantage was eliminated by a verbal, but not a spatial, dual task. Further, effects of language were most pronounced on more difficult, finer discriminations. English speakers tested on the identical stimuli did not show a category advantage under any condition. These results demonstrate that categories in language can affect performance of basic perceptual color discrimination tasks. Further, they show that the effect of language is online, because it is disrupted by verbal interference. Finally, they show that color discrimination performance differs across language groups as a function of what perceptual distinctions are habitually made in a particular language.

They end on a philosophical note:

The Whorfian question is often interpreted as a question of whether language affects nonlinguistic processes. Putting the question in this way presupposes that linguistic and nonlinguistic processes are highly dissociated in normal human cognition, such that many tasks are accomplished without the involvement of language. A different approach to the Whorfian question would be to ask the extent to which linguistic processes are normally involved when people engage in all kinds of seemingly nonlinguistic tasks (e.g., simple perceptual discriminations that can be accomplished in the absence of language). Our results suggest that linguistic representations normally meddle in even surprisingly simple objective perceptual decisions.

To me this is another important paper that puts sapir-whorf hypothesis on the forefront. I would love to hear from those who do not endorse the spair-whorf hypothesis as to what they make of these results?

hat tip: Neuroanthropology blog.

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good mood= intuition + good mood = psychosis?

I recently blogged about how good mood may lead to diminishing of working memory and I have blogged in the past regarding how good mood + intuitive thinking styles may lead to Magical thinking.

Now there appears a new study that shows that good mood, in and of itself, may lead to more reliance on Intuition or conscious gut feelings while making decisions. DeVries et al use the Iowa Gambling Task to ascertain whether an experimental manipulation (watching 2.5 minutes happy or sad clips) affected the performance on the IGT, in the window (20 to 40 cards from start) when the participants were using the conscious gut feeling or intuition to form their decisions . What they found was that a good or happy mood made the people rely more on their intuitive or conscious gut feelings vis-a-vis controls and the negative mood had the opposite effect of making them more deliberative. This was reflected in respectively good and poor performance on the second block of trial in the two affect cases . I present below the abstract of the study.

The present research aimed to test the role of mood in the Iowa Gambling Task . In the IGT, participants can win or lose money by picking cards from four different decks. They have to learn by experience that two decks are overall advantageous and two decks are overall disadvantageous. Previous studies have shown that at an early stage in this card-game, players begin to display a tendency towards the advantageous decks. Subsequent research suggested that at this stage, people base their decisions on conscious gut feelings. Based on empirical evidence for the relation between mood and cognitive processing-styles, we expected and consistently found that, compared to a negative mood state, reported and induced positive mood states increased this early tendency towards advantageous decks. Our results provide support for the idea that a positive mood causes stronger reliance on affective signals in decision-making than a negative mood.

I tend to put this in a broader context and it is apparent to me that good mood leads to more reliance and usage of intuitive thinking styles. this may even be mediated by the fact that working memory deficits associated with good mood prevent a deliberative approach to problem solving and instead favors an affective driven or intuitive approach. Taken together this implies that good mood leads to more intuitive thinking and decision making style. However, we have seen earlier that good mood and an intuitive thinking style are a dangerous mixture and lead to Magical thinking styles. Taken together this would mean that good mood induces a positive runaway process that causes more reliance on intuitive thinking which causes more
Magical thinking style and ultimately the good mood spirals upwards from good mood to Mania to full blown psychosis. I am excited by these linkages as they may provide additional points of attack where one can address the cognitive factors behind Mania / Psychosis and lead to additional therapeutic paradigms. How about you? Does this correlation and causation form Mood to Intuition to Magical thinking excite you too?

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Psychosis and Autism as Diametrical Disorders of the Social Brain: converging evidence!!

Readers of this blog will be familiar with my model of Autism/ Schizophrenia and I recently found an online article by Crespi et al that elegantly summarizes the theory that autism and Schizophrenia are on a continuum of phenotypic variations related to cognition and the social brain.

I will be using images and text from that article heavily, so go ahead and read the original article too, which is very well-written and thought provoking.


The Authors contend that autism and schizophrenia are on a continuum where cognition is concerned with Autistics leaning towards mechanistic cognition, while schizophrenics leaning towards mentalistic cognition. This should be a familiar story to readers of this blog.



They discuss the various contrasting features of Autism and Schizophrenia. They contend that Autism is made up of three dimensions: language and communication difficulties, social reciprocity difficulties and creative or imaginative difficulties (which they term as repetitive and restricted behavior) .



They contrast this with the psychotic spectrum in which they include the three corresponding dimensions as Unipolar depression, bipolar disorder and Schizophrenia.


They then go ahead and list a variety of evidence from studies of growth, development, neuroanatomy, cognition, behavior, and epidemiology for diametric phenotypes in autism and psychosis. I reproduce below the table (click to enlarge - the tables are a must read!!) which highlights salient differences in phenotypes:





The authors have their own theory (which seems very plausible to me) regarding why Autism and Schizophrenia are diametrically opposite. This they contend is due to evolutionary arms race between the child and mother for scarce resources mediated by maternal and paternal imprinting genes.



They do a brilliant job of describing their theory so I quote from them:

Further hints that imprinted genes may have something to do with autism and psychosis come from the finding that autistics have heavier birth-weight(especially males) while schizophrenics are lighter – just as you would expect if paternal genes were more prominent in autism. Again, more paternal and/or less maternal genetic influence is sometimes implicated in cancer(another form of over-growth) and here the striking finding is that schizophrenics have less cancer than autistics despite the fact that the former smoke much more. Again, there is evidence that autistics by contrast to psychotics show early brain growth at the expense of the mother.

The article's discussion is enlightening as it also throws light on other previous researchers who have hypothesized along similar lines. Alas The Mouse Trap doesn't get a mention, But Nettle , regarding whom I have blogged before gets a mention.

Our hypothesis can be conceptualized at two interacting levels: (1) the diametric architecture of autistic and psychotic-spectrum conditions (Badcock 2004), and (2) the underpinnings of this structure in dysregulated genomic imprinting. A diametric structure to autism and schizophrenia has been considered for some traits before: thus, Abu-Akel (1999) and Abu-Akel & Bailey (2000) suggested that autism and schizophrenia represent extremes on a continuum of theory of mind skills from hypodevelopment to hyper-development, Frith (2004b) described 'under-mentalizing' in autism and 'over-mentalizing' in schizophrenia, and Nettle (2006) anticipated an autism psychosis spectrum in noting that “autistic traits are in many ways the converse of the unusual experiences component of schizotypy”. However, most previous research on autism and psychosis has considered the disorders to be etiologically unrelated (or has considered the negative symptoms of schizophrenia in terms of autism), although both disorders are believed to be underlain by dysregulated development of the social brain (Broks 1997; Emery 2000; Burns 2004, 2006). By our hypothesis, autism and psychosis represent extremes on continua of human cognitive architecture from mechanistic to mentalistic cognition, with balanced cognition at the center (Figure 4). Each set of conditions is extremely heterogeneous but also highly convergent, in that diverse genetic, epigenetic and environmental effects can generate similar cognitive phenotypes (Happé 1994, p. 2; Keverne 1999; Seeman et al. 2005; Badcock & Crespi 2006; Happé et al.2006). These striking convergences are mediated, in our view, by the dynamics of social brain development, with under-development in autistic conditions and hyperdevelopment in psychotic conditions (Badcock 2004), Further tests of this hypothesis should focus on assessing the breadth and depth of diametric phenotypic structure to autistic and psychotic spectrum conditions, and testing for tradeoffs between mentalistic and mechanistic thought and ability.

I am thrilled to see my theory also being investigated in parallel and worked on by distinguished scientists and am grateful for the scientific work going in this area. I am sure we will soon see more research supporting my thesis.

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