ADHD = Different Reward / Motivation Pathway?

More on the evolving story about ADHD biology and reward. Rather than ADHD appearing as a fixed deficit in executive function, increasing evidence suggests that children (and adults) with ADHD behaviors are showing impulsivity mainly in non-reward situations.

In this recent study from Germany, 8-13 year old boys diagnosed with ADHD showed a much greater ability to inhibit impulsive behavior on the go/no-go test if rewards- monetary or social were involved. The differences were striking between the two groups...whereas only 12.5% of the control group slowed down their behaviors and improved their responses in the control group, 43.8% of the ADHD group slowed down their behaviors and exhibited fewer false alarm rates. The implications for findings such as this are significant - if making external or situational changes to a task could eliminate or significantly reduce impulsivity, the impulsivity is not a disease or fixed deficiency, but rather a behavioral response to specific conditions implicit in the task.

The researchers are very careful to not overstate their findings: "given the heterogeneity within the ADHD population,it is arguable that dysregulated reward-seeking behavior alone can account for all cases of ADHD. Nevertheless, reinforcement theories are able to explain most of the ADHD symptoms [44]. ADHD possibly represents the final outcome of diverse and discrete neurodevelopmental
pathways with an 'extreme reward approach pathway' leading to impulsive and overactive behavior."

One might also argue whether the term "extreme" is unduly negative to describe what could be an alternative and not necessarily pathology reward pathway. Why locate the fault in the children? Why not say that 1/4 of the population of children don't respond well in an "understimulated" environment. Why should a child be motivated to perform a meaningless go/no-go task?

So what about the child diagnosed with ADHD whose symptoms are worst with uninteresting (at least to the child) classroom work? Perhaps the rewards of socializing, dodgeball at recess, doodling a design for game, or designing a space ship out of legos are more rewarding (and deserving of focus and care) than Mad Math Minutes? Our prior blog post on fMRI activation patterns for money-induced incentives and ADHD now seem more compelling...



p.s. Data such at this also lend positive support for the use of more extrinsic rewards when tasks are not completed by children with ADHD.

Greater Sensitivity to Social Rewards In Children with ADHD pdf
Eide Neurolearning Blog: Amphetamines Blunt Rewards in Normal Subjects
Eide Neurolearning Blog: Money, Motivation, ADHD, and the Brain

See What I'm Saying - Cross Modal Sensory Perception and Sensory Training

There's an interesting new book from UC Riverside psychologist Lawrence Rosenblum called See What I'm Saying.

In it, Rosenblum chronicles various individuals who have been able to fine tune their sensory systems to an exquisite degree.

Examples include individuals like John Bramblitt, a blind painter who can feel differences color mixtures and uses his strong kinesthetic sense to paint.




There's also individuals like Daniel Kish who have refined their sense of hearing to such a high degree that they can walk as if they see.  By using a system of auditory clicks, they can listen for how the sounds bounce of objects near to them so that they can identify size, shape, and characteristics of items in their surroundings. Kish can lead other blind mountain bikers on expeditions using this strategy of clicks to perceive the path and the positions of his fellow bicyclists.Check out this remarkable video:



Sensory training has a tremendous neurorehabilitative potential for individuals with significant sensory deprivations like blindness or deafness, but it also holds tremendous potential for mixed sensory conditions that may involve multiple sensory systems like birth injury, autism, or sensory processing disorders in general.

Can't tell you how remarkable it is for me to see stories like this - as a neurologist, it was such an entrenched idea that rehabilitation or therapy were only possible for motor and not sensory problems. With new computer-based technologies too, it is so much easier to envision specific targeting of sensory weaknesses and ways to train and systematize the knowledge that comes in from various sensory channels.

Mixed sensory conditions will present more of a challenge, but probably just require more isolation and training of sensory-sensory or sensory-motor pairings.

The Unexpected Benefits of Poor Working Memory - ADD and Lazy Genius?

I've been enjoying reading The Benefits and Perils of Attentional Control by Decaro and Beilock, and its more than a professional interest (see Confessions of a Limited Working Memory Victim).

Many people have very poor working memories - in my case it's a very bad auditory verbal working memory. Always had it, I can't blame age. I can't keep much in my head whether it's someone telling me directions, typing in a computer password someone's told me, or listening to a lecture (fortunately I can write things down). I don't listen to books on tape.

I am not alone, of course - this is a common feature of ADD and some dyslexics, and seems to be more common in certain types of thinkers...especially those with strong spatial or visual thinking preferences like physicists or some artists for instance. Usually having a poor auditory verbal working memory is thought of as only a bad thing, that's why the chapter in the book Effortless Attention was so interesting to read.

Researchers made the following observations about low working memory victims (LWMVs):

- LWMVs had more diffuse attention on divided attention tasks (they noticed what they were told to ignore) - obviously good for some situations, bad for others
- LWMVs were less likely to choke under emotional pressure
- LWMVs were more likely to switch to simpler problem solving strategies when the option became available (lazy, but flexible)
- LWMVs were also more flexible with problem solving approaches in general - especially when domain-specific distractors were present. High working memory people, especially those with some expertise in a domain tended to make errors, persisting too long at dysfunctional approaches when they thought they could use their expert backgrounds
-  LWMVs were more likely to use associative strategies in solving problems
- Although LWMVs were poorer at rule-based category learning, they were better than HWM folks and information-integration tasks...that involve associative skills more than rule-based and high working memory demands

Some take-home points:

"Working memory supports a persistent approach in ways that are sometimes too selective. Such reliance on cognitive control not only may limit the discovery of new problem-soving approaches but may also lead to an attention-dependent learning strategy that overrides a more optimal associative strategy."

"It is commonly believed that the more extensively information is processed and attended to, the more optimal performance may be...however, greater attentional control capabilities can impede performance, and individuals with less cognitive control can excel beyond their higher capacity counterparts by effectively utilizing simpler strategies."  Could this be 'big picture thinking'?

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Ambivalent vs. Black-and-White Thinking

Are you a black-and-white or are you shades of gray? Whether you're one or the other affects how you make decisions.

From a recent study, "...college students were asked to write an essay coming down on one side or another of a contentious issue, regarding a new labor law affecting young adults, while other groups of students were allowed to write about both sides of the issue. The students forced to choose a side reported feeling more uncomfortable, even physically sweating more, says Frenk van Harreveld , a social psychologist at the University of Amsterdam who studies how people deal with ambivalence."

"Because of their strongly positive or strongly negative views, black-and-white thinkers tend to be quicker at making decisions than highly ambivalent people. But if they get mired in one point of view and can't see others, black-and-white thinking may prompt conflict with others or unhealthy thoughts or behaviors."

Depending on the situation, it might be better to be black-and-white, whereas in others gray.

Ambivalent thinking is generally thought to be a more mature way of thinking - usually thought of in adults - but clearly also seen in young children and often among the intellectually precocious  or gifted.

"Ambivalent individuals' ability to see all sides of an argument and feel mixed emotions appears to have some benefits. They may be better able to empathize with others' points of view, for one thing. And when people are able to feel mixed emotions, such as hope and sadness, they tend to have healthier coping strategies, such as when a spouse passes away, according to Dr. Larsen. They may also be more creative because the different emotions lead them to consider different ideas that they might otherwise have dismissed."

But ambivalent thinkers are often slow decision-makers,  easily sucked into analysis-paralysis.  

Researchers suggest that ambivalence vs. black-and-white thinking may be a general temperamental trait. It's probably a good idea to consider when trying to figure out what makes a student struggle certain assignments or writing prompts.  When a paper doesn't get written, too often it's chalked up to ADD or executive function problems, but that only obscures the real issues. Some students benefit by having a name for what they're experiencing (ambivalence) while others may need a different approach to expressive the complexity of their opinions or stance.

Usually we find that people with a strong 'ambivalent' thinking style don't like sound-bytes. They need more words to fully express the depths of their opinions and the gray areas, and also a structure to their ideas that gives a better approximation to the depth of what they experience than any short reply.


It might be that ambivalent thinkers are better suited to complex environments that require decision-making under uncertainty. In situations such as these, rules, events, and observations are not black-and-white.

Check here if you're looking for more on the brain basis of ambivalence; important areas seem to be anterior cingulate, frontal pole, and lateral orbital frontal cortex

Ambivalence and Decision Making

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