Archive for April, 2010

Am happy, will broaden-and-build; am angry, will narrow-and-save

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Sympathetic (red) and parasympathetic (blue) n...
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Regular readers of this blog will be aware of my conception of positive emotions  in terms of promotion focus and negative emotions in terms of prevention focus. Today I will try to relate this to the specific action-tendency theory of negative emotions and broaden-and-build theory of positive emotions (as proposed by Barbara Fredrickson).

First its instructive to distinguish between negative and positive emotions. Negative emotions, like Fear, Anger, Disgust, traditionally have been conceptualized as specific action tendencies that get triggered or activated by particular type of threatening situations/stimuli. I view them as sensory driven. A stimuli impinges and is either presumed to be attacking/trespassing (thus arousing anger) or dangerous and threatening survival (thus arousing fear) or intimidating and overbearing (thus arousing sadness and disengagement)  or sickening and to be avoided (thus arousing disgust) ; in all cases a stimuli or situation acts as an immediate trigger for a specific action tendency – that of defending, fighting or fleeing, disengaging and surrendering or vomiting and keeping away.

In contrast consider positive emotions like Joy, Interest, Contentment and Love. They all happen when the environment is safe and bodily needs are met- they are not need driven, but growth oriented. They are not based around survival, but around growth.  they are non -specific thought action repertoire that is a broadened set and is not narrowly focused- rather one of the prime effects of positive emotions is to broaden attention, thought/cognition,  actions and interactions. I consider them as motor driven. they are not a response to a stimulus. Rather they are specific patterns of spontaneous action tendencies and opportunities to practice giving outlet to ones spontaneous action tendencies in a safe environmental. That is why every sort of play- be it physical rough-and-tumble or intellectual play of creativity or social play of flirting – is associated with the positive emotions.

To make my analogy more clear consider the fact that actions can be classically conditioned (and thus response to US/CS stimulus) or operant conditioned (and thus not reactive or reflexive but intrinsically driven and proactive) and while former may be more or less determined by  the external stimulus and internal associations and is deterministic in nature, the latter has spontaneous behavioral variability and initiation as its premise and has room for free will.  What I claim today is that negative emotions are reactive and thus keep you stuck in deterministic rut, while positive emotions are expansive and provide opportunities for exercise of free will in safe and playful environments by encouraging spontaneous behavioral fluctuations and felkxibility.

It has been found time and again that positive emotions are associated with a broadening and resource-building effect. Consider Joy. It encourages one to engage in acts for acts sake or encourages rough and tumble play- it builds physical resources.  Consider Interest . It encourages one to engage in exploration of a domain- be it actual physical domain or conceptual domain – it builds cognitive maps and cognitive or intellectual resources. Consider contentment. It encourages one to engage in reflection and self assessment and self integration – it builds psychological resources. consider Love (care-giving variety not romantic which is pathological and more of a negative emotion). It encourages one to engage in reciprocal interactions and to explore, act on and reflect on the other- it builds social resources.

Thus it is evident that positive emotions do help to broaden and build. That much has been proved by Barbara’s research program .  My additional claim is that negative emotions are sensory oriented and reactive while positive emotions are motor oriented, spontaneous and proactive. By signalling safe environments in which behavioral flexibility can be played around with they push us to relate to life more intrinsically.

Perhaps another analogy will be relevant.  there is a sympathetic nervous system and there is parasympathetic system. the sympathetic system helps us respond to stressful situations and readies the body. the parasympathetic restores the body and helps in regeneration of the body. So do negative emotions help us react to outside threats and make the mental-illness dimension while positive emotions help match intrinsic activity to opportunities in the environment and makes the mental health dimension.

The former (mental illness continuum)  is a zero sum game- if I win someone looses. For eg if a dominance hierarchy is there and I am on top I may feel manic while the person at bottom may feel depressed..but as long as dominance and survival and predation and germs are there the negative emotions would be there …the latter (mental health continuum)  is a win-win game.  There are more opportunities for everyone to fare better if everyone is positioned high on mental health spectrum as then doors to creativity and productivity open right then and there for all concerned. thus, I have become an advocate of the positive psychology movement and would like more efforts devoted to study of positive emotions.

Fredrickson, B. (1998). What good are positive emotions? Review of General Psychology, 2 (3), 300-319 DOI: 10.1037//1089-2680.2.3.300

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Environmental factors like teacher quality and SES affect the full flowering of potential

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This should be a no-brainer: in an era when increasingly words like ‘gene-environment interaction‘ are bandied around, it would be self evident that for full flowering of a prototypical trait, the genotype has to get the right environmental inputs. In absence of the right environmental conditions, the genetic differences may be masked and the trait under consideration suffer from universal stunted growth, thus even different genotypes leading to same phenotype -that of survival trait. contrast this with the condition where the environment provides rich conditions for the flowering of the trait under consideration. Here the trait will be having maximal value and would be a thriving trait value. Here genotype differences , if any , would be accentuated and become visible as difference sin phenotype expression.

If the above is a bit abstract , take the concrete example of SES and the corresponding low environmental condition and its relation to IQ/brain/cognitive ability. In an impoverished environment differences due to genetics would be masked and everyone will have a low IQ/cognitive ability. As opposed to this in an enriched environment condition, not only the average IQ would be higher (a thriving condition), there would be more differences in the IQ of children/people concerned as the right environment will make it possible for genetic effects to come into play and determine the IQ/cognitive ability. The above is a bit paradoxical and counter-intuitive- one advocates environmental interventions only to see that effects of environment becoming less for the trait and effects due to genetics becoming more prominent as more and more conducive environment is provided. The rationale for providing the right enriched environment /high SES to all would thus be not to eliminate inequality (inequality would paradoxically be accentuated) ; but to raise the trait value to maximum possible under the right environmental and that perhaps is for the good of all.

I have debated this issue earlier in my low IQ and SES series of posts, but thought will comment on the same in light of two articles that I cam across recently. The first article is a bit old, but has the devastating effect of waking one form ones slumber as one realizes that low SES leads to brain effects in low SES children that are akin to those faced by normal children/people who suffer brain damage due to stroke etc. I came across this via this science daily release tweeted by someone today (forgot the source).

The second study is a brand new one , published just today (and I have just read the extract and accompanying Sci Am article). The study, using identical and fraternal twin studies, in essence found that children’s reading ability was largely genetic (82 % genetic component), but that teacher quality mattered a lot. The genotype was able to flower fully when teacher was high h=quality- not only the reading ability was better; differences were accentuated. In contrast, when teacher quality was low, environmental had a much stronger effect by leveling everyone to a smaller value. To quote from the article:

“When children receive more effective instruction, they will tend to develop at their optimal trajectory,” said study lead author Jeanette Taylor in a prepared statement. “When instruction is less effective, then children’s learning potential is not optimized and genetic differences are left unrealized.”

The researchers found that good instruction promoted stronger reading development. Without it, children were less likely to reach the potential conferred by their genes. “When teacher quality is very low, genetic variance is constricted, whereas, when teacher quality is very high, genetic variance blooms,” they report. While teacher quality appears to be an important contributor, other classroom factors, such as classmates and resources, might also influence reading ability, the researchers noted.

To me, the results are important, though self-evident. Hopefully they will seal the endless confusion on the matter and allow a more reasoned dialogue and intervention to happen where IQ and SES/enriched environment is concerned.

Taylor, J., Roehrig, A., Hensler, B., Connor, C., & Schatschneider, C. (2010). Teacher Quality Moderates the Genetic Effects on Early Reading Science, 328 (5977), 512-514 DOI: 10.1126/science.1186149
Kishiyama, M., Boyce, W., Jimenez, A., Perry, L., & Knight, R. (2009). Socioeconomic Disparities Affect Prefrontal Function in Children Journal of Cognitive Neuroscience, 21 (6), 1106-1115 DOI: 10.1162/jocn.2009.21101

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Dreaming as delirium, protoconsciousness or epiphenomenon?

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J Allan Hobson, has never shied form  making bold departures from existing trends when it comes to dream research. At the time when Freudian notions of dream interpretation and dreams-as wish-fulfillment were at it speak, he proposed a theory that dreaming or the subjective state be distinguished from the underlying REM sleep physiological brain state and that dreaming or subjective experience thereof may be an epiphenomenon associated with the underlying physiology. In other words REM sleep may have a function, but the dream state accompanying it is just an epiphenomenon- our minds trying to make sense of random internally generated signals, in the absence of signals from the external world.

In between Hobson has written a book titled Dreaming as Delirium, in which he compares dream state to that of the psychotic state,  especially the delirium accompanying such psychotic states. while dream sttes are naturally cut-off from reality ( no sense inputs or motor outputs) , psychosis, that is indeed characterized by lack of contact with reality, may also thus be predominantly  internally generated and close to the dream state in its characterization.

In his most recent review paper in Nature reviews Neuroscience , he compares the dream state to that of proto consciousness. As per him, proto consciousness is made up of raw emotions and perceptions while secondary consciousness is made up of awareness about perceptions and emotions and meta cognitive processes. He now endows dreams/REM state with some functional significance. He believes that dreams provide and opportunity for inbuilt genetic scripts and schema to be played out and fine tuned against external real-world scenarios. In this view dreams would still be significant as they provide a window to out internal scripts that are present from birth. He doesn’t put this across in so many words and this is my interpretation, but that is what I could sort of intuit.  You are encouraged to read the original paper which is relatively much more accessible as compared to his 1977 paper.

While some people even deny any function to consciousness and call it an epiphenomenon, and thus it would be very hard to convince them of any significance to the bizarreness of dreams; yet I believe that Dreams , not of the garden variety type, but those that we ourselves consider significant, do have a significance and are not mere epiphenomenon. It may be akin to everyday consciousness not having any major role than that of post-hoc narrative weaving; but at some time free will does assert itself and conscious will rules at some rare occasions.  So not all dreams are created equal, some indeed are more than epiphenomenon.  They may be delirium like in nature but perhaps tend towards more of hyper consciousness than proto consciousness.

Hat tip: Neuroskeptic

Hobson, J. (2009). REM sleep and dreaming: towards a theory of protoconsciousness Nature Reviews Neuroscience, 10 (11), 803-813 DOI: 10.1038/nrn2716

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Two views of brain function: Reflexive/reactive or Intrinsic/proactive?

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Marcus Raichle, who had initially discovered the default brain network, has a new review article in TICS, that argues that brain activity should be understood as primarily an intrinsic and proactive process rather than a reflexive or reactive process.

He bases this argument on the fact that resting brain consumes 20 % of body’s energy requirements , but this is the consumption of default mode network within the brain. If the brain is engaged in some task than energy consumption does not increase by more than 5 %. thus the meat of  the brain energy is consumed for DMN and is used for intrinsic functions , not directly related to task demands.

In an experimental setting, it is very easy to be lured by the task related fMRI activity or ERP’s as they reflect responses of brain to carefully controlled variables in lab settings; however one should not lose sight of the fact that the apparent noise and random intrinsic activity is there for a purpose and may sound mysterious as it may be correlated more to spontaneous activity rather than directly mappable to measurable environmental variables.

Another argument Raichle gives relates to the visual system.  Here the input from Retina is highly degraded (from 10 to the power of 10 bits per sec to 100 bits per sec that is supposed to be bandwidth for conscious processing) and Marcus argues that the anatomy of cortex with may feedback connection from higher cortical areas suggests that much of the activity is predictive in nature trying to fit the reduced environmental input to a rich internal representation. Of course Jeff Hawkins and others have been similarly arguing for a more predictive role of the entire cortex, rather than a reactive and information processing role as is traditionally assumed.

He then goes on to argue that the coherence observed in the spontaneous fluctuations in fMRI BOLD signals , especially in the DMN are reflective of more than daydreaming or mind wandering and this intrinsic activity needs investigation as it is present even in non-conscious states. He also posits that these spontaneous fluctuations representing intrinsic activity lead to behavioral variability and I am somehow reminded of Bjorn Brembs (@brembs) paper on flies and how they showed spontaneous behavioral fluctuations…if only one could identify the DMN in flies and monitor its fluctuations using an fMRI machine:-) , one would have hard data to prove Rachelle’s claim.

He does relate spontaneous fluctuations in BOLD signal to slow cortical potentials (SCP) and the SCP’s to cortical excitability and stakes a claim that thus spontaneous fluctuations measure the degree to which cortical neurons are ready to be fired. this provides a handle by which we can investigate how and what function the intrinsic activity serves (answer: the phase of SCPs codes and predicts the most probable signal timing from the external world). the brain is in a constant flux between trying to predict and looking for novel stuff.

That brings me to Linas and his book I of the Vortex. I have only read it partially but was fairly impressed by its argument for the primacy of motoricity. I encourage readers to read that book for an alternative view from the sensory and perception driven psychology and neuroscience mainstream approach. I firmly believe that we re primarily motor creatures rather than sensory ones and more clues could be found about us suing the motor approach to cognition/ consciousness/ whatever.

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M. Raichle (2010). Two Views of Brain function Trends in Cognitive Sciences DOI: 10.1016/j.tics.2010.01.008

divergent

The Creativity-dopamine (b)linkage: more brains and bonkers connections

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rh?zom?ng Cam?ra?Obscura pl?ats . .
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Creativity is certainly different from intelligence; it is usually gauged as the ability to make novel and useful unique contributions to a field. Creativity itself is not a unified construct but can be broken into convergent creativity (involving more focused approach) and divergent creativity (involving more widening and loosening of associations).

It has been evident for quite some time that there is a connection between insanity (especially bipolar/schizophrenia spectrum) and creativity , especially as evidenced by the creative bent of schizotypal people. See for example this article covering a recent study that looks at exactly the same issue. However, most of these studies rely on a unitary construct of creativity that does not do full justice to the correlations that could be found if convergent and divergent creativity was distinguished and effect of intelligence was factored out. The new study by Hommel, B. does just that.

Schizophrenia/psychosis as many will know from their elementary neuroscience knowledge is associated with dopamine dysfunction; specifically it is believed that high baseline dopamine levels are there in schizophrenics/psychotics. So it was not unreasonable for Hommel et al to hypothesize that dopamine should have some relation with creativity possible higher dopamine associated with high creativity. However, dopamine has shown an inverse U relation for many other factors and thus they were cautious and tried to fit both linear and quadratic graphs to their data. But we are moving ahead of ourselves. Before they could find the underlying relation between dopamine and creativity, they had to measure these things accurately.

They measured dopamine using Eye Blink Rate (EBR): that is how many time you blink in a minute. For creativity , they measured Convergent Creativity using a remote association task (don’t go by the name …the task has only one answer and measures convergent thinking) . for eg. a subject is given three words (say time, hair, stretch) and have to come up with a word that is commonly related to all three (answer: long) . this reliably measures creativity but of he convergent type. For Divergent thinking , they administered the Alternate Uses task (AUT),a task that requires one tocome up with novel uses of everyday objects like brick, toothpaste etc. The responses to AUT were further coded for fluency (how easily one could come up with alternatives measured by total no. of responses) , flexibility(the number of different categories used or how remote the mind wandered) and elaboration (the level of detail surrounding the use). They also measured fluid intelligence using Raven’s progressive matrices.

They then conducted experiments (administered the tests to subjects) , collected data and analyzed the results. The main findings of interest to us is that they found a inverse u shaped relation between dopamine (EBR) and flexibility dimension fo divergent thinking. This effect was present even when the effect of intelligence was factored out. thus both low dopamine, as well as too much dopamine is detrimental to flexible divergent thinking/creativity and schizotypals , placed precariously between normals and psychotics are best placed to be the most creative as they presumably have the optimum dopamine levels. the authors also argue that schizophrenics dopamine levels should not be brought down indiscreetly by using anti-psychotics (which reduce dopamine levels) but they should be brought in the optimum range of dopamine functioning. this obviously has immense importance and treatment implications. No wonder creative people feel stiffed when on anti-psychotics- their dopamine levels are being brought down way too much.

The other interesting finding was that dopamine (EBR) was negatively ad linearly related to convergent thinking. Thus, it is evident that convergent creativity and divergent creativity are different constructs and while dopamine has a complex quadratic relationship with divergent thinking, that with convergent thinking is linear though not very comforting. It seems that as dopamine levels increase the ability to narrow focus diminishes and this would be concordant with other studies linking dopamine to ADHD for example.

Overall, a view of how brains and bonkers are two sides of the same coin is emerging and it is exciting to note that many previous inconsistencies in literature around this issue may have to do with not differentiating and decomposing creativity into its many components and not looking for inverse u shaped effects.

Chermahini SA, & Hommel B (2010). The (b)link between creativity and dopamine: Spontaneous eye blink rates predict and dissociate divergent and convergent thinking. Cognition PMID: 20334856

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