Living on the edge of chaos; implications for autism and psychosis

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I serendipitously came cross this article today about how our brains are self-organized criticality or systems living on the edge of chaos. There are many interesting ideas and gold nuggets in that article, and I'll briefly quote from it.

In reality, your brain operates on the edge of chaos. Though much of the time it runs in an orderly and stable way, every now and again it suddenly and unpredictably lurches into a blizzard of noise.

Neuroscientists have long suspected as much. Only recently, however, have they come up with proof that brains work this way. Now they are trying to work out why. Some believe that near-chaotic states may be crucial to memory, and could explain why some people are smarter than others.

In technical terms, systems on the edge of chaos are said to be in a state of "self-organised criticality". These systems are right on the boundary between stable, orderly behaviour - such as a swinging pendulum - and the unpredictable world of chaos, as exemplified by turbulence.

The quintessential example of self-organised criticality is a growing sand pile. As grains build up, the pile grows in a predictable way until, suddenly and without warning, it hits a critical point and collapses. These "sand avalanches" occur spontaneously and are almost impossible to predict, so the system is said to be both critical and self-organising. Earthquakes, avalanches and wildfires are also thought to behave like this, with periods of stability followed by catastrophic periods of instability that rearrange the system into a new, temporarily stable state.

Self-organised criticality has another defining feature: even though individual sand avalanches are impossible to predict, their overall distribution is regular. The avalanches are "scale invariant", which means that avalanches of all possible sizes occur. They also follow a "power law" distribution, which means bigger avalanches happen less often than smaller avalanches, according to a strict mathematical ratio. Earthquakes offer the best real-world example. Quakes of magnitude 5.0 on the Richter scale happen 10 times as often as quakes of magnitude 6.0, and 100 times as often as quakes of magnitude 7.0.

These are purely physical systems, but the brain has much in common with them. Networks of brain cells alternate between periods of calm and periods of instability - "avalanches" of electrical activity that cascade through the neurons. Like real avalanches, exactly how these cascades occur and the resulting state of the brain are unpredictable.

Two of the power laws that are found in human brains relate to the phase shift and phase lock periods of EEG/fMRI or human brain systems etc. As per this PLOS comp biology paper:

Self-organized criticality is an attractive model for human brain dynamics, but there has been little direct evidence for its existence in large-scale systems measured by neuroimaging. In general, critical systems are associated with fractal or power law scaling, long-range correlations in space and time, and rapid reconfiguration in response to external inputs. Here, we consider two measures of phase synchronization: the phase-lock interval, or duration of coupling between a pair of (neurophysiological) processes, and the lability of global synchronization of a (brain functional) network. Using computational simulations of two mechanistically distinct systems displaying complex dynamics, the Ising model and the Kuramoto model, we show that both synchronization metrics have power law probability distributions specifically when these systems are in a critical state. We then demonstrate power law scaling of both pairwise and global synchronization metrics in functional MRI and magnetoencephalographic data recorded from normal volunteers under resting conditions. These results strongly suggest that human brain functional systems exist in an endogenous state of dynamical criticality, characterized by a greater than random probability of both prolonged periods of phase-locking and occurrence of large rapid changes in the state of global synchronization, analogous to the neuronal “avalanches” previously described in cellular systems. Moreover, evidence for critical dynamics was identified consistently in neurophysiological systems operating at frequency intervals ranging from 0.05–0.11 to 62.5–125 Hz, confirming that criticality is a property of human brain functional network organization at all frequency intervals in the brain's physiological bandwidth.

Further, as per research by Thatcher et al, the EEG phase shift is larger in people with high IQ, while phase lock is smaller in the people with high IQ.

Phase shift duration (40–90 ms) was positively related to intelligence (P < .00001) and the phase lock duration (100–800 ms) was negatively related to intelligence (P < .00001). Phase reset in short interelectrode distances (6 cm) was more highly correlated to I.Q. (P < .0001) than in long distances (> 12 cm).

Further, in this paper , thatcher eta look at autistics and conclude that the people with autism show some deficits in phase shift and phase lock.

Results: In both short (6 cm) and long (21 – 24 cm) inter-electrode distances phase shift duration in ASD subjects was significantly shorter in all frequency bands but especially in the alpha-1 frequency band (8 – 10 Hz) (P < .0001). Phase lock duration was significantly longer in the alpha-2 frequencyband (10 – 12 Hz) in ASD subjects (P < .0001). An anatomical gradient was present with the occipitalparietal regions the most significant.
Conclusions: The findings in this study support the hypothesis that neural resource recruitment occurs in the lower frequency bands and especially the alpha-1 frequency band while neural resource allocation occurs in the alpha-2 frequency band. The results are consistent with a general GABA inhibitory neurotransmitter deficiency resulting in reduced number and/or strength of thalamo-cortical connections in autistic subjects 

It is interesting that in the original new scientist article , thatcher speculates that the pattern in schizophrenia may be reverse of what is seen in autism (exactly my thoughts, though the confounding of low IQ with autism may explain his autism results to an extent):

He found that the length of time the children's brains spent in both the stable phase-locked states and the unstable phase-shifting states correlated with their IQ scores. For example, phase shifts typically last 55 milliseconds, but an additional 1 millisecond seemed to add as many as 20 points to the child's IQ. A shorter time in the stable phase-locked state also corresponded with greater intelligence - with a difference of 1 millisecond adding 4.6 IQ points to a child's score (NeuroImage, vol 42, p 1639). Thatcher says this is because a longer phase shift allows the brain to recruit many more neurons for the problem at hand. "It's like casting a net and capturing as many neurons as possible at any one time," he says. The result is a greater overall processing power that contributes to higher intelligence. Hovering on the edge of chaos provides brains with their amazing capacity to process information and rapidly adapt to our ever-changing environment, but what happens if we stray either side of the boundary? The most obvious assumption would be that all of us are a short step away from mental illness. Meyer-Lindenberg suggests that schizophrenia may be caused by parts of the brain straying away from the critical point. However, for now that is purely speculative. Thatcher, meanwhile, has found that certain regions in the brains of people with autism spend less time than average in the unstable, phase-shifting states. These abnormalities reduce the capacity to process information and, suggestively, are found only in the regions associated with social behaviour. "These regions have shifted from chaos to more stable activity," he says. The work might also help us understand epilepsy better: in an epileptic fit, the brain has a tendency to suddenly fire synchronously, and deviation from the critical point could explain this. "They say it's a fine line between genius and madness," says Liley. "Maybe we're finally beginning to understand the wisdom of this statement."

Thus, it seems Autism and Psychosis are just two ways in which self-organized criticality can cease to do what it was designed to do- live on the edge , without falling on either side of order or chaos.

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Bozo Sapiens: a book review

Bozo Sapiens :why to err is human, is a book that tries to document the frailties of our decision making process and the underlying psychological mechanisms behind them.

Written with a lay audience in mind,it is written in an easy to read manner and is fun to read. As per the site, it is in the tradition of books like Blink and Stumbling on happiness and plans to cater to the same market segment of people who are interested in psychology and how it affects day-to-day lives. while most of the psychology studies were already familiar to me, they would be novel for a lay audience and would definitely interest and entertain and also inform and guide. I,myself, cam across a few new and worthwhile studies and feel enriched having been made aware of them. As is prone to writing for a popular audience, the Kaplans often gloss over or do not highlight all the subtleties involved, but it must go to their credit that they are able to explain the studies lucidly and clearly,without significantly diluting on the scientese involved. the only peeve I have is that the sections and studies covered in them somehow felt unconnected and not flowing in a smooth manner from one to the other.

The organization of the chapters is decent- one chapter focusing on perceptual errors, another on action-based errors while yet another on errors based on group mentality. The section on perception seemed to me better and the section on groups perhaps the weakest. Despite its title it is not a bleak view of humanity and knowing our heuristics, biases and design features/bugs will only help us act better. It is an easy read and perhaps would be savored by those who do have a general interest in psychology; for the experts there are some nuggets spread here-and-there and that may make it worthwhile skimming through the book.

Disclaimer: I received a free e-copy of the book for review.

PS: would my readers like to see more book reviews featured on the mouse trap ? some books that I would love to review and highlight include books by Nettle : happiness, personality; gazzaniga: mind's past riddley: genome, nature via nurture etc etc. Do let me kno wvia commnets/ skribit suggestions using left sidebar.

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If it’s abstract you gel in, if it’s concrete you stand out..Or Why I compare myself to a man but not to men.

Mick Jagger via last.fm

Readers of this blog will be familiar with research by Bargh et al that showed that priming with stereotypes led to assimilation of those traits by the primed subjects. To recall, when asked to wait, those primed with rudeness interrupted the experimenter more than those primed with patience/nicety primes. Also those primed with elderly stereotype walked more slowly, away from the experimenter after the end of the alleged experiment, than those in neutral condition. These are all very well known findings and more so as they have been included in numerous pop-sci books.

Sceepar et al provide a very sober qualification for the above findings, contrasting how stereotype traits priming (abstract concept priming) do indeed lead to assimilation of stereotype in behavior/self-schema; but exposing to concrete, extreme exemplars belonging to stereotyped category has an opposite and paradoxical effect of leading to social comparison with the exemplar and thus leading to contrast behavior or behavior where the subject tries to distance oneself from the stereotype. Thus, if primed with the stereotype of professors, and thus the trait intelligence, and then subjected to an intelligence/knowledge test, then the subjects would perform better than baseline condition; but if primed with Einstein (a concrete exemplar of professor/intelligence), then one may lead to compare with Einstein, deduce that one is not so great, but indeed stupid or a bozo in comparison, and thus perform badly in the subsequent test based on this self-comparison. This is what they theorized and this is what they found.

In the second study they reused the Bargh paradigm of priming with elderly stereotype and replicated the results; the twist they added was adding a condition in which after priming with the elderly stereotype, an elderly exemplar was presented; this condition led to comparison and thus to contrast behavior whereby the subjects walked faster after the experimental manipulation in this exemplar condition.

Their third study was essentially a study to nail down the mechanism (social comparison) behind the contrast behavior observed. After priming with Einstein and professor in two separate conditions, the subjects were exposed to a lexical task, that was designed to discover if concepts like intelligence , stupidity had been primed and if so , was any of them also bound to the self schema. They found that indeed in the Einstein condition the concept of stupidity was bound to the concept of self, thus only exemplars, like Claudia Schiffer or Einstein led to social comparison, but not abstract notions like supermodels or professors. They end with an advice to Mick Jagger which has to be read in original to be savored.

We close with perhaps one of the more trivial of these implications. This concerns advice we might offer celebrities such as Mick Jagger and other stars known for their predilection for supermodels. If these people share the popular stereotype of supermodels found among our participants, they would be wise to restrict themselves to a single such partner (i.e., an exemplar) on intellectual as well as moral grounds.

I now also post some snippets form the excellent article, freely available on the web, which you should read in its entirety.

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Common mechanisms for learning (past), navigation(present) and dreams (future?)

Sorry for the brief(?) hiatus. I have left my day job to start a venture and so am a bit preoccupied. Hopefully, the mouse trap should benefit from the new arrangements.
Today I would like to highlight a recent study from MIT that once again highlighted the fact that the same brain mechanisms are used for envisaging the future as are used for reminiscing about the past.  The study was performed on rats and found that the rats sort of replayed their day-time navigational memories while they were dreaming. This in itself is not a new news and has been known for a long time; what they found additionally is that the rats also , sort of replayed the navigational memories/ alternatives in their head at a faster rate, to sort of think and plan ahead. This use of replaying the traces to think ahead to me is very important and cements the role of default netwrok in remebering the poast and envisaging the future.

When a rat moves through a maze, certain neurons called "place cells," which respond to the animal's physical environment, fire in patterns and sequences unique to different locations. By looking at the patterns of firing cells, researchers can tell which part of the maze the animal is running.

While the rat is awake but standing still in the maze, its neurons fire in the same pattern of activity that occurred while it was running. The mental replay of sequences of the animals' experience occurs in both forward and reverse time order.

"This may be the rat equivalent of 'thinking,'" Wilson said. "This thinking process looks very much like the reactivation of memory that we see during non-REM dream states, consisting of bursts of time-compressed memory sequences lasting a fraction of a second.

"So, thinking and dreaming may share the same memory reactivation mechanisms," he said.
"This study brings together concepts related to thought, memory and dreams that all potentially arise from a unified mechanism rooted in the hippocampus," said co-author Fabian Kloosterman, senior postdoctoral associate.

The team's results show that long experiences, which in reality could have taken tens of seconds or minutes, are replayed in only a fraction of a second. To do this, the brain links together smaller pieces to construct the memory of the long experience.

The researchers speculated that this strategy could help different areas of the brain share information - and deal with multiple memories that may share content - in a flexible and efficient way. "These results suggest that extended replay is composed of chains of shorter subsequences, which may reflect a strategy for the storage and flexible expression of memories of prolonged experience," Wilson said.

To me this seals the fate of hippocampus as not just necessary for formation of new memories, but also for novel future-oriented thoughts and imaginations.

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Top 10 Psychology blogs for the Curious Minds

I feel honored to have been asked by blogs.com to compile a list of top 10 psychology blogs for the curious minds. Any list , such as this, is necessarily subjective and being limited in nature, cannot do justice to all the other psychology blogs that I equally love and follow on a regular basis or other interesting blogs, which I am perhaps not aware of. 

The top 10 blogs are presented in an alphabetical order and reflect those that I find most interesting, insightful or fun to read.  Hopefully the mouse trap community would concur and benefit from following these blogs as well. Do check out the list and by the way of comments to this post,  add some other blogs that you think are equally interesting and catering to the curious amongst us.

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BlogCampPune2: A thank you note!

I attended the BlogCampPune2 last Saturday and it was a fun event - bringing diverse people , all driven by the passion of blogging, in the same room and providing them an opportunity to get to know each other well.

Special thanks go to the unorganizers, Tarun, Bhavya et al. for unorganizing it and to all others who showed up at the event and participated. It was my first blogcmap/tweetup/ unconference/ any offline activity and I met many of my online friends in real life, for the first time.

I was already looking forward to meeting Navin Kabra, Amit Paranjape,Meeta Kabra, Dhananjaye Nene, Sneha Gore, Vishal Gangawane, Tarun Chandel and many others and was gratified when that happened; but the icing on the cake was to find other unexpected contacts like Mahendra Om  also present there, or making new and interesting contacts like Annkur of Only Gizmos.

Some of the sessions were really interesting- Annkur with his 'Mistakes were made (but not by me) (but by me)' presentation ; or Navin with his 'What blogs can learn from newspapers' presentation provided some good food for thought and something to take home with you and apply to your blogging later.The informal talk by Meeta and how her dependence on third-party marketing backfired provided new insights. Thakkars' impromptu session stressed the importance of humor and fun and how presentation matters.  The only regret form the blogcamp was the fact that due to some last minute rescheduling, I and Dhananjaye had to take sessions at the same time and we ended up missing each others presentations.  I had already gone through Dhanajaye's presentation , which he had loaded prior to the event on his site, and was really looking forward to his talk.

To those of you who missed the event, search for #blogcamppune on twiiter or go to this FriendFeed page to get a sense of real-time excitement and reprting.  I am sure , the post-blogcamp blog posts and tweets and press covergae would be aggregated at some place and I'll link to it soon here.My own persentation can be found here. 

Thanks again to all who were there!

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Best of Tweets: 24-06-09

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Not much activity last week, yet:

1. Aripiprazole, Dopamine, and Well-Being - Science or Selling Point? http://ff.im/-44CUt
2. The origins of Language http://ff.im/-44HnN
3. Beauty: symmetry versus averageness http://ff.im/-44QNO
4. Nerve Cells and Glial Cells: Redefining the Foundation of Intelligence http://ff.im/-4h2Wc
5. On Anonyminity http://ff.im/-4hsav
6. The Dearth of Artificial Intelligence http://ff.im/-4hGAD
7. pls RT/Buy: Just published my novel on Lulu http://bit.ly/ZN9uWtw   

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The Sculptor and the Sandman: A novel as much about psychosis as about the human condition

Last night I somehow got inspired, brushed my manuscript that was written about 6 yrs earlier, and in a span of just 4-5 hrs was able to create a sell able paperback book out of it, all thanks to new publishing tools like the lulu.com. Of course, the manuscript, had been read/ re-read, revised and edited by me, all these years, so I'm sure the quality of the product would be great.

Some of you may be aware that I write prose and poetry and have a poetry focussed blog called The Fools Quest. Perhaps, the right place to promote my novel, The Sculptor and the Sandman, would be that blog, instead of the mouse trap; but then again, that novel is as much a piece of fiction, as it is a psychological treatise- my view of what psychosis is, how it manifests and what some of the triggers may be. The tale is grounded in my undersantding of the psychotic condition and I am sure that my readers with exclusive interest in the psychologcial aspects would still find reading that novel worthwhile. Of course, I know that many of your are multi-dimensional, and value arts, as much as science, and reading the novel would be an artistic pleasure in itself- even when not being bogged down by the psychological aspects and the truth or falsity of my depiction of the psychotic condition - the novel can be enjoyed in its own right . Reading it may also help you connect with me on a different level- exposing aspects of myself that were never apparent while reading the mouse trap.

As always I would love feedback, reviews etc and would sincerely request that you give the novel a try. The paperback edition is priced at $10.80 and a downloadable version is priced at $2.50; I am sure it would prove value for money and you will end up buying further copies for your friends and recommending it to others. It is at present just available at lulu.com , but soon will be available at all other major stores like amazon.com.

You can read an excerpt from the novel at the lulu.com site and here is the blurb from the back cover:

The sculptor and the sandman is a fable set in the India of the twenty first century. A tale of passion, obsession, madness and rebellion, the story revolves around how the protagonists move in and out of madness, competing as well as caring for each other, and how their life becomes inextricably twined with that of the narrator, a coconut water vendor.

A tale in which episodes of frank psychosis seem more understandable and reasonable than the unbearable normality of everyday life, the tale is a grim reminder of how misunderstandings and malice work together to weave the different strands of our life together and how silver linings are present in the darkest of clouds hovering over the horizon.

Seen from another perspective, the tale documents different approaches to find meaning and value in this modern world, a world devoid of absolutes. One approach may seem more absurd and futile than the other, but perhaps it is not so much about the 'right' value system or frame of meaning, as it is about the need for 'a' value system or a frame of meaning- to each his own cross.

Please, Please, Please do read the novel (for that you'l need to buy it!), share it with others( if you indeed like it) , recommend/review it on your blogs and do send me comments, either using this page, the lulu reviews page etc or by directly sending your comments to me at sandygautam@yahoo.com, even if the comments are not positive or encouraging. Any feedback is much better than no feedback. Depending on the feedback, I have the sequel to the sculptor and sandman already in draft stage but I need some reassurance as to whether the efforts are worthwhile and whether  there is a need and appreciation for this type of writing.

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