Posts tagged ADD and ADHD

Cognitive control: when less is more!

Yesterday I wrote a post about ADHD and creativity and how the frontal lobes hypo-function and dopamine may be the mediating factors involved.  Today I serendipitously came across this article by Thomson-Schill et al in which they posit that frontal cortex hypofunction during childhood is beneficial, on average, as it enables convention learning and thus linguistic acquisition.

What they basically mean is that frontal cortex has been found to be involved in cognitive control i.e. in higher cognitive functions like planning, flexible thinking etc ; and the frontal cortex does this by biasing the competitive responses elicited by a stimuli by goals /existing beliefs / other task related information that is maintained in the working memory. To take an example, cognitive control is often measured by tasks such as the stroop task. the strrop task measures how well you are able to suppress the prepotent response tendency of naming the color-term itself by the task-relevant constraint that you name the color of the term instead. when a color term like ‘green’ is presented in Red color, then the green as well as red linguistic response compete with each other. In the absence of frontal biasing in teh direction of color ie.e red, we are apt to name the color-term itself i.e green by default which is the habitual response. Children , who have less well-developed frontal cortices generally perform poorer at the stroop task than adults as their frontal cortex does not bias or tilt the scales in favor of the color used rather than the color-term presented.

The authors claim that this inability to bias results on the basis of pre-existing knowledge/beliefs leads to a greater ability to learn. They posit that learning conditions (that maximize competition )  are different from performance conditions (where one response needs to be selected or competition minimized) and the child’s brain is optimized for learning by not having frontal inhibition and control. An example they give is filtering noise form signal which the child are able to do, but adults can’t. for eg. if a new language has a phrase ‘et tu brute’ and 75 % of times it is in this form and 25% of times it is of the form ‘et tu vous Brute’, then adults will tend to probability match and select the utterance/ utter themselves phrase ‘et tu brute’ 75% of times and ‘et tu vous Brute’ 25 % of times. This is because when they want to utter the phrase their existing knowledge that sometimes the other phrase is also used, makes them sensitive to variations. In child’s brain on the other hand a competition between the two phrases takes place and as there is no moderating influence involved, the outcome hundred percent of the time is ‘et tu brute’. Thus, they are able to learn conventional meaning of a phrase/word etc more easily than an adult who gets bogged down by variations. Thus sometimes, less is more!

However the reason I got hooked to this study is the implications they draw for ADHD/Autism and creativity. I’ll quote them verbatim on the issue:

Central to our proposal is the claim that the timing of PFC development has been the target of selection and, therefore, that variations in timing are functionally meaningful. Recent neuroimaging studies have revealed potentially important differences in the timing of PFC development across typical and atypical individuals. Variations in the trajectory of PFC maturation (based on repeated measures of cortical thickness) have been associated with cognitive measures in typically developing children (Shaw et al., 2006). Children with attention-deficit hyperactivity disorder (ADHD) exhibit a delay in cortical maturation that is most prominent in the PFC (Shaw et al., 2007). In contrast, children with autism spectrum disorders (ASD) undergo early maturation of the PFC (Carper, Moses, Tigue, & Courchesne, 2002). A better understanding of the implications of these timing changes for both learning and performance may illuminate some of the behavioral and cognitive patterns associated with these diagnoses (e.g., impaired acquisition of social conventions in ASD), as well as offer a fertile ground for testing the validity of our hypothesis that typical PFC development involves a trade-off in favor of learning to the detriment of performance in infancy and early childhood.

This gels quite nicely with what I have been speculating for some time, that ADHD and Autism are opposed and that ADHD is childhood equivalent of psychosis. ADHD kids are bound to be good learners, more divergent creative and have better social and linguistic skills. Autistic kids on the other hand would be better performers (say child prodigies in memory etc) , more convergent thinkers, and have less social and linguistic skills- one mechanism of which may be lesser ability to learn social and linguistic conventions- like the usage of metaphorical terms.

On creativity this is what the authors say:

Creativity—the ability to approach an object or a situation from an alternative perspective—may benefit from the unsupervised competition that occurs in the absence of prefrontal control. Consider one common assessment of creative thinking, the Alternative Uses Task: When attempting to think of ways to use an object in some atypical way, adults struggle. In this case, an active PFC might, paradoxically, hinder flexible thinking, because the representation of the object is sculpted by prior experience and expectations. Interestingly, young children are immune to this kind of functional fixedness (German&Defeyter, 2000). Successful performance in similar tasks of ideational fluency has been associated with EEG changes in prefrontal regions (e.g., Mo¨lle, Marshall, Wolf, Fehm, & Born, 1999). Furthermore, patients with PFC damage solve insight-problemsolving tasks better than do their healthy counterparts (Reverberi, Toraldo, D’Agostini, & Skrap, 2005). This apparent flexibility of behavior can be interpreted as a stimulus-driven response: A mind that is at the mercy of its environment is not shaped by expectations or beliefs. This interpretation highlights a parallel between functional fixedness and probability matching, in that both of these ‘‘adult’’ phenomena involve biasing stimulus–response associations based on expectations. This proposal suggests new avenues of investigation into the processes that support creative thought and into putative relations between creativity and psychological disorders associated with hypometabolic prefrontal function (i.e., a state of lower energy consumption in the PFC, as in bipolar disorder, for example).

The above analysis of creativity in terms of hypofunction of frontal cortex bodes well for my theories of creativity-ADHD relationships as well as creativity-psychosis (bipolar etc) relationship, both of which involve developmental or functional hypofucnction of frontal cortex.

Thompson-Schill, S., Ramscar, M., & Chrysikou, E. (2009). Cognition Without Control: When a Little Frontal Lobe Goes a Long Way Current Directions in Psychological Science, 18 (5), 259-263 DOI: 10.1111/j.1467-8721.2009.01648.x

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ADHD and creativity

Brainscan of brains with and without ADHD
Image via Wikipedia

ADHD has traditionally been conceptualized in terms of deficits- that of attention , impulse control or motor restraint; but the new neurodiversity paradigm forces us to take a more balanced look and acknowledge the strengths that the ADHD kid may have- divergent thinking, spontaneity and high energy and vitality.

That brings me to research by Cramform that shows that the symptoms that define ADHD/ADD- hyperactivity, impulsivity and distractability are just the negative connotation and spin put on some of the traits that define highly creative and gifted child–  the traits of Vitality, spontaneity and daydreaming/wandering phenotype.

But first things first. ADHD , as many of the readers will know , is defined by three primary symptoms- hyperactivity or the restlessness and fidgety or squirming behavior of the kid; impulsiveness or the inability to control impulses manifest in overt behavior like getting up in class and interrupting;  and distractibility where the kid ends up paying too much attention, even to stimuli that are extraneous and should be ignored, thus leading to fleeting attention! ADHD is a traditional classroom misfit and thus a traditional teachers nightmare. However, one should note that a traditional teacher is not too much impressed by the highly creative kid too, who proves to be a bit too much to placate and who doesn’t conform too easily.

But what could be the mechanism why ADD/ADHD must be so closely related to and resembling creativity traits as to be indistinguishable from it by behavioral symptoms alone? I believe dopamine and frontal cortex are the culprit. We have seen in the past that dopamine is related to creativity and we have seen that frontal cortex is related to creativity; and we have also seen that dopamine is related to ADHD. As a  matter of fact ADHD on a neurotransmitter level is characterized by dopamine’s quirky behavior , while on the neuroanotomic level is known by the late development of frontal cortex that is an inhibitor to other areas like motor areas and impulsive areas (basal ganglia and sub-cortical regions)  thus leading to symptoms of  impulsivity and hyperactivity. In creative people too, especially in divergent form of creativity, we see that creativity manifest itself when dopamine comes into play and when frontal regions give up their control of other regions of the brain thus making remote associations more likely.

Of course dopamine is not just involved in ADHD, but also in Psychosis and thus my theory of Autism and Psychosis as opposites would claim that ADHD is childhood form of psychosis and is opposed to Autism. There is already some support for that idea with autism and ADHD being discovered as opposites and with ADHD more common in bipolar probands.

The dual symptoms of ADHD as inattention and as hyperactivity/ implusivity are easy to conceptualize when one sees that one is trying to maximize predictive ability / minimize surprise and also maximize rewards by being flexible in one;s behavior and taking risks rather that persevering on the well trodden path. Both attention-allocation and action-selection are sensitive to dopamine and in one particular phenotype result in more leaning towards flexibility, distracatibility, hyper energy and arousal and more novelty and thrill seeking. The desire is to explore and not to exploit. The hunter rather than the farmer as per Hartman’s model. These same are characteristics of the creative phenotype- those touched with fire- and thus on the move literally or figuratively- always seeking new combination and ideas and exploring uncharted territory.

Perhaps its time we stopped negatively labellings the gifted, creative ADDers as difficult kids, but rather design and structure classrooms around them that bring their potential to the fullest and make them bloom fully. Lets not stifle the creativity. Lets not devalue the immense energy and joy these child exhibit and the creative potential they embody.

Cramond, B. (1995). The Coincidence of Attention Deficit Hyperactivity Disorder and Creativity University of Connecticut, The National Research Center on the Gifted and Talented. Other: ED388016

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