The ever-thoughtful GNIF Brain Blogger has just published a brand new 7th edition of the Synapse. The articles range form thoughtful arguments for de-stigmatization of mental health issues to careful analysis of the recent vegetative-state-showing-consciousness studies. Sprinkled along the way are articles elaborating the trade off between proliferation and tumor suppression in human brain.
Have a happy reading!
As per this new Google initiative, one can now follow Fifi and other Chimpanzees in real-time as they roam around the Gombe Chimpanzee park using the Google Earth Featured Content. All you have to do is download Google Earth , choose the Jane Goodall's Gombe Chimpanzee Blog in the Featured Content section visible in the left sidebar and enjoy!
Although, I was not able to zoom in a live image of a chimpanzee ( as all of them were foraging in the dense forest and thus not visible), but with perseverance one may catch a live video of a chimp playing in an open area. Also, this would be of help to the primatologists amongst us, who could track the movements of these chimpanzees.
More power to Google!
A couple of recent news articles on neuroeconomics, lead to some surprising insights regarding how addictions like Gambling could be self-addictive and how some specific neurological malfunctioning may lead to people fairing better in games of chances and making more 'rational' gambles.
The first article in the New Scientist refers to a recent research by Chris Frith et al at University College London, UK in which the authors found that people who had been given dopamine agonists (like L-DOPA) were able to determine the winning strategy involved in a gambling game early then those who were given placebo. The study contained choosing symbols - some of whom were associated with large chances of winning, while others were associated with average chances and still others were associated with financial penalties and should ideally be learned as avoidable symbols.
What they found was that dopamine facilitated the early learning of the symbols that were associated with (monetary) winning outcomes or rewards as compared to controls, but had no effect on the learning of the avoiding or punishment symbols. This, they hypothesize is due to the fact that people get a Dopamine surge whenever 'rewarded' and when base dopamine levels are high (it has already been administered prior to the betting game) this leads to greater strength of dopamine reward signal , thus leading to faster learning of the winning strategy. The fact that dopamine does not affect the learning of negative outcomes, confirms that the effect selective and due to the 'rewarding' nature of dopamine as opposed to a general improvement in learning due to dopamine administration.
The participants played a computer game in which they were repeatedly shown pairs of unmatched symbols, and had to choose one or the other without being told anything about them beforehand.
Unknown to the participants, one symbol gave them an 80% higher chance of winning £1, whereas another symbol gave them only a 20% higher chance of winning. Other symbols incurred financial penalties.
The volunteers on dopamine prospered because they identified the winning symbols faster than the haloperidol treated patients. And the winning effect was more pronounced if they actually received money in the study.
The dopamine recipients only noticed winning symbols, however. The chemical did not appear to alert recipients to “losing” symbols.
Learning from losing is controlled by other chemicals in the brain, the most dominant probably being serotonin, a chemical linked with depression, Frith concludes.
This brings up some interesting scenarios. If one has started gambling somehow, then as one keeps gambling further, the successive wins would generate more and more dopamine surges (as baseline dopamine increases after a few wins), the gambler would start identifying the winning patterns, and the strength of winning patterns and rewards associated with them would continue to get stronger in the gambler's mind; there would be no corresponding effect on the learning of negative or losing strategies by him and consequently his learning would be skewed in such a way that winning outcomes would be disproportionately perceived as being rewarding as compared to the losing outcomes - thus in the gamblers mind loses are processed in a 'normal' way ; but wins or winning strategies are perceived differently in the sense that they would be learned more strongly, earlier and more persistently - as each win would result in more and more dopamine surge and thus skew the learning in favor of the winning strategy more and more. this is a vicious circle- the gambler is getting more and more dopamine surge and is also becoming better and better at identifying the winning strategies- thus its difficult to convince him otherwise that he is gambling in vain- what he doesn’t realize that he is not attaching a corresponding increased negative outcome to losses or is learning the losing strategies also at the same rate.
The other article is a good review of the field of neuroeconomics in the New Yorker. It touches on many current issues in neuroeconomics, but what is most relevant to us here is the concept of loss aversion, whereby people perceive losses of what they already have as more aversive than a wasted chance of making an equivalent or more gain. To paraphrase from the article:
If you present people with an even chance of winning a hundred and fifty dollars or losing a hundred dollars, most refuse the gamble, even though it is to their advantage to accept it: if you multiply the odds of winning—fifty per cent—times a hundred and fifty dollars, minus the odds of losing—also fifty per cent—times a hundred dollars, you end up with a gain of twenty-five dollars. If you accepted this bet ten times in a row, you could expect to gain two hundred and fifty dollars. But, when people are presented with it once, a prospective return of a hundred and fifty dollars isn’t enough to compensate them for a possible loss of a hundred dollars. In fact, most people won’t accept the gamble unless the winning stake is raised to two hundred dollars.
In one study, Camerer and several colleagues performed brain scans on a group of volunteers while they placed bets on whether the next card drawn from a deck would be red or black. In an initial set of trials, the players were told how many red cards and black cards were in the deck, so that they could calculate the probability of the next card’s being a certain color. Then a second set of trials was held, in which the participants were told only the total number of cards in the deck.
The first scenario corresponds to the theoretical ideal: investors facing a set of known risks. The second setup was more like the real world: the players knew something about what might happen, but not very much. As the researchers expected, the players’ brains reacted to the two scenarios differently. With less information to go on, the players exhibited substantially more activity in the amygdala and in the orbitofrontal cortex, which is believed to modulate activity in the amygdala. “The brain doesn’t like ambiguous situations,” Camerer said to me. “When it can’t figure out what is happening, the amygdala transmits fear to the orbitofrontal cortex.”
The results of the experiment suggested that when people are confronted with ambiguity their emotions can overpower their reasoning, leading them to reject risky propositions. This raises the intriguing possibility that people who are less fearful than others might make better investors, which is precisely what George Loewenstein and four other researchers found when they carried out a series of experiments with a group of patients who had suffered brain damage.
Further, the article notes that people with orbitofrontal, right insular or amygdala damage, are less fearful or are less able to integrate the fearful or 'emotional' response of the brain and are thus able to make decisions that are more risky then their normal counterparts. Thus, the counterintuitive conclusion that damages to these areas may make one a better investor/ gambler etc.
Each of the patients had a lesion in one of three regions of the brain that are central to the processing of emotions: the amygdala, the orbitofrontal cortex, or the right insular cortex. The researchers presented the patients with a series of fifty-fifty gambles, in which they stood to win a dollar-fifty or lose a dollar. This is the type of gamble that people often reject, owing to loss aversion, but the patients with lesions accepted the bets more than eighty per cent of the time, and they ended up making significantly more money than a control group made up of people who had no brain damage. “Clearly, having frontal damage undermines the over-all quality of decision-making,” Loewenstein, Camerer, and Drazen Prelec, a psychologist at M.I.T.’s Sloan School of Management, wrote in the March, 2005, issue of the Journal of Economic Literature. “But there are situations in which frontal damage can result in superior decisions.”
If we club the two studies together, one may come to a surprising conclusion that to become a good speculative investor or gambler you may need to temporarily knock out your parts of the brain involved in emotional decision making (one may use TMS here) and also additionally take a dopamine does to learn the rewarding strategies and actions early on. This may be the only way for us to counter the tyranny of loss aversion that nature has imposed on us and move towards that ideal of Homo Economicus.
Nature Reviews Neuroscience has an interesting article that summarizes the latest findings about neurogenesis and synaptic plasticity in adult mice and how exposure to enriched environments and experience leads to later onset of diseases in transgenic mice models of human diseases like Huntington's disease, Alzheimer's disease and Parkinson's disease, fragile X and Down syndrome, as well as various forms of brain injury.
This is exciting news and lends credence to the fact that for full flowering and upkeep of your mental faculties, mental exercises and stimulating mental environment is a must.
Hat Tip : The Frontal Cortex
If you have always been interested in writing a book concerned with Cognitive Neuroscience, Psychology press is currently soliciting proposals for the same. More information at Cognitive Neuroscience Arena.
Please find below the detailed requirements
>>
Contemporary Approaches in Cognitive Neuroscience
Psychology Press are launching a new series called "Contemporary Approaches in Cognitive Neuroscience".
Series Editors:
* Stanislas Dehaene, Collège de France, Paris
* Alvaro Pascual-Leone, Harvard Medical School
* Jamie Ward, University College London
Invitation to Authors:
Reflecting contemporary and controversial issues in the study of cognitive neuroscience, the series aims to present a multi-disciplinary forum for cutting edge debate that will help shape this burgeoning discipline.
It offers leading figures in the field and the best new researchers an opportunity to showcase their own work, expand on their own theories and place these in the wider context of the field.
If you would like to submit a proposal to be included in this series we would like to hear from you! Titles in the series may be authored or edited; the only requirement is that each book must aim to make a contribution to a specific topic by reviewing and synthesising the existing research literature, by advancing theory in the area, or by some combination of these missions.
Please send your proposals to: book.proposals@psypress.co.uk
>>
Welcome to the sixth edition of Synapse, a biweekly Carnival, devoted to aggregating the best neuroscience postings and research on the web.
History of Psychology:
Let's learn our lessons from the history of Psychology. Here, we have a very informative posting from the Neurophilosopher delineating the gradual historical process through which the concept of a Neuron got established. I am tempted to post a snippet from the post, which describes the etymology of this Carnival's name.
Also during this decade Sir Charles Sherrington described the junction between nerve and muscle, and named it the ’synapse’ (from the Greek roots syn, meaning ‘together,’ and haptein, meaning ‘to clasp’) in 1897.
Happy blogging till then!
Technorati Tags: carnival , cognition
Sphere: Related ContentFellow bloggers!
Its that time of year again, when one needs to take some time out, from the usual blogging activities, to submit one's most interesting posts, for inclusion in the next edition of that esteemed Carnival called Synapse. This is more important than any grant request that you may need to make. So don't forget to nominate your , or other bloggers, best entries from the past weeks for inclusion in the sixth edition of Synapse that would be published right here at The Mouse Trap on 3rd September.
Please submit the entries in time for inclusion on 3rd Septemeber. Submission guidelines here.
I was browsing through a blog post by Developing Intelligence and came across this link to a talk by Greenfield et al, regarding pretend play capabilities of Chimpanzees and Bonobos. In this, it is asserted that Chimpanzees and Bonobos are able to achieve level4 of pretend play, that is observed in Humans by themselves and if they are scaffolded or guided by Humans in their Zone of Proximal Development, they can also achieve the stage 5 (the highest stage achieved) . The levels were levels of pretend play as described by McCune and Agayoff (2002) and based on descriptions by Piaget (1951). No web searches by me could lead me to the definition of these levels on the web and I would be glad if any of the readers of this blog, who are familiar with these levels, could update me on this by posting in the comments.
However, I did come across some other levels or stages associated with pretend play and could link them up with my previous postings on moral, cognitive, perspective and language development.
To outline my position, I intend to show that pretend play or Symbolic play follows the same stages as involved in language acquisition and the analogy is true for both Language syntax as well as lexicon acquisition. Further, it may be the case, that pretend play stages precede corresponding language stages and are necessary for successful language acquisition in all stages.
First, I would like to distinguish between the form of pretend play and its contents. The form of pretend play may consist of different predicates
Thus, a pretend play P = R P O
The child may start initially start by forming a concept of pretenses as something that is not really true (stage I); start creating pretenses with real life objects e.g. using real life objects in pretentious acts (like pretended talking on an actual mobile) (stage II); gradually combine two of these (using banana as a mobile and pretending to talk on it) (stage III); gradually graduate to elaborate pretensions whereby not only objects stand for something else and actions stand for something else, but also the role assumed by the child may vary, and is usually that of adults (stage IV); and in later stages the roles , object-representations etc may even be novel and not something that the child has encountered in its usual socializing (stage V).
This staged manner is analogous in language acquisition to babbling (whereby one starts creating words), one word speech (whereby one starts using a word for representing a thing), two word speech (whereby one combines actions, nouns etc in two word phrases to create sentences) and finally telegraphic speech (too much bound by rules learned from observation of adults) and finally adult speech based on pragmatics.
More interesting is some stages described in "Multiple Perspectives on Play in Early Childhood Education" By Olivia N Saracho, Bernard Spodek for individual lexicons- like that for object substitution.
Elena Bugrimenko and Elena Sminova have proposed five stages in symbolic play (ages 18 to 30 months)
It is interesting to note that individual elements of a pretend play like object-substitution, themselves go through developmental stages.
Another interesting study mentioned in "Understanding Child Development: For Adults Who Work with Young Children" By Rosalind Charlesworth refers to the actual pretense act and how that pretense act becomes more complex as the child goes through different developmental stages. In the following example, the 'pretended act of feeding/eating' should be considered.
According to Nicolich(1977), toddlers develop through a sequence of stages in their play, as seen in the following example:
It is interesting to observe that in the above examples, the child in stage 1 is developing his sensory-motor abilities to indulge in a pretend act of eating; in stage 2 he actually indulges in a pretend act that is directed towards himself. In stage 3, he directs the pretense act towards someone else ( a doll) , in stage 4 he goes through a sequence of activities and rituals as observed in a normal social context, in stage 5 he indulges in elaborate planning, setting up the stage and understands that other people can also pretend juts like him and directs the pretend act towards another human being.
To develop the staged theory of pretend play further, consider role-playing agent (that is the child indulging in pretense play). The discussion is based on the following stages (doc) available on the web. (italicized comments mine)
Stage I: Imitative Role Play: In this initial stage of play, children try to act, talk, and dress like people they know. Children use real objects as props. They depend on an element of reality in their play. For instance, a child may pick up a telephone and pretend to “talk on the phone like Mommy” or hold a doll and “feed the baby.” One starts developing a concept of a 'pretended role' but needs to ground that with the actual props that are used and this play is a solitary activity.
Stage II: Make-Believe Play: In the second stage, children’s play is enriched by their imaginations. Now less dependent on concrete props for role-playing, children may use a string as a firefighter’s hose, or an envelope may be Mommy’s briefcase. The ability to make-believe moves beyond the scope of real props or costumes. Children also learn to use their imaginations to invent actions and situations. Dramatic play is no longer confined to real-life events. At this stage, children often use such play to help them understand feelings or deal with fears and worries. Point to note that one has developed a concept of 'pretend roles' and does not need to depend on external props for achieving that role. The role-playing is still mostly a solitary activity.
Stage III: Socio-Dramatic Play: Socio-dramatic play emerges at the time children begin seeking the company of others. Socio-dramatic play includes elements of imitative play and make-believe play; however, it stands apart from the earlier stages in that it requires verbal interaction between two or more children. Because of its interactive nature, socio-dramatic play necessitates planning. One child chooses to be the teacher and the other the student; one child can be a firefighter and the other a would-be victim. Because of its more complex story lines, socio-dramatic play requires that children spend a significant amount of time in this type of play. This play, in my view, is characterized by role-play involving two persons. One knows what role one is supposed to play and what the other person has to play and one may even switch roles during the play. This marks the beginning of 'social' pretend play.
To the above stages I will add two of my own stages of role-playing:
Stage IV : Mythological/ Archetypal / adult role playing : Here the child may enact the different roles played by mythological or archetypal characters that are prevalent in his culture. He may one minute play Ravana, the next Rama, the next Laxmana, the next Jatauyu and the next Sita (all characters of Ramayana). Thus, he starts understanding that one may have different roles and pretenses at different times and a typical sequence of play would involve permuting between different roles in succession. One is exposed to not only the fact that different roles can be assumed sequentially, but also gets exposed to how it feels to act in that particular social role that is prevalent in one's culture. One would normally imitate adult roles and also play with adults (mother) in this role-playing.
Stage V: Novel role-playing: Here the role-playing with peers becomes more important. Also one seeks novel roles like that of an Alien invader and uses the imagination to come up with novel pretend roles. One may pretend to be novel animals - an El-zebra - an elephant that has stripes and runs very fast. One may pretend not to be a 'role' like a doctor, but a 'person' like one’s best friend and say that I am Bill and act like Bill (for e.g. cuddling dolls like Bill does). Thus, one may move from 'pretend roles' to pretend persons' and even go on the do mimicry using voice intonation, gait etc to pretend to be another person!! One has mastered the art of pretend role-playing.
I’ll briefly try to link this up with another post by Developing Intelligence relating symbol usage with Language development/evolution. Please read the post now, as I wont repeat the arguments made by David Premack here and assume that the reader has read them via the above link.
Premack tries to make an argument for uniqueness of existence of language in Humans due to some Symbol manipulation related abilities that we humans have over other apes. I'll not go into the argument whether, and to what extent, these capabilities exist in Apes (I guess Premack is a sufficiently good authority on that), but will try to show how those symbolic abilities unique to humans, as outlined, are involved in the staged development of pretend play.
To sum up, there seem to be interesting parallels involved in all developmental stages, be that of Moral development, Language development or Symbolic Usage (Pretend Play) development and this tells us about some of the constraints, templates and guidelines under which development takes place.
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