April 27, 2009

• Getting High on Getting Hip

  In simplest terms, “getting hip,” (for you young people who are not hip to the slang of the Beat Generation) just means learning.  One can be hip to anything, but nobody is fully hip to everything.  That would require omniscience beyond the capacity of the human brain.  “Getting high,” in a broad sense, means simply attaining a state of euphoria.

  Defining my terms is not my favorite thing to do, but many people who read what I write might think otherwise.  Communication is one of my favorite things to do, and I have found that if I don’t define my terms my communication often suffers.  Therefore, I frequently start by defining terms and often digress into definitions.  So, sue me.

  I don’t remember exactly when I started studying psychology.  I started learning about the workings of my brain/mind before I started using the word, “psychology.”  Psychologists have been studying me since I was seven years old and scored about 240 on the Stanford-Binet IQ test.  The number there is approximate because nobody told me anything about my results at the time, and the only thing my mother was told was that I had scored, in second grade, at the level of a high school senior.  I later did the calculation myself.

  I have always been intensely curious, wanting to learn and to know — everything.  Curiosity is probably my most dominant trait.  Curiosity, I have been told, is an attribute of intelligence.  Intelligence is one of the subjects I have wanted to learn and know about ever since people started talking (mostly behind my back) about my intellligence.

  About a quarter of a century ago, I learned about dopamine and a few other brain chemicals related to learning and memory.  I was reading magazines like Psychology Today and Scientific American.  Those articles led me to other avenues of investigation and I got into smart drugs, brain food, and neurotech.  I regularly discuss these things with my family, which consists of a brainy old guy who was getting intensely into Mensa and its sex and politics about the same time I dropped out of Mensa, and a young man whose intelligence sometimes makes us elders feel stupid.

  The Kid and I concluded long ago that one of the things that differentiates us from neuro-normal people is that we get high on learning.  We have asked others, and the ancedotal evidence we have accumulated suggests that those who are more intelligent (defined as those who tend to score higher on intelligence tests), generally get a bigger charge out of nailing down a new fact, making a previously unrealized connection, or mastering a new skill.  I have had some odd conversations with some dim folks who apparently didn’t even understand what I meant by “learning” or any particular feeling associated with it.

  I have concluded that people (like me and my kid) who get big kicks out of learning will probably tend to learn more than people who do not generate those big dopamine jolts in their brains.  We have also theorized that the neurochemical reward system could account for our tendency to become easily addicted to video games.  Designers set them up to both drive and reward learning.

  Our intuitive leaps and anecdotal evidence are being confirmed or supported by science. Recently, I found a few things online:

  Accumulating data support a critical involvement of dopamine in the modulation of neuronal activity related to cognitive processing. The amygdala is a major target of midbrain dopaminergic neurons and is implicated in learning and memory processes, particularly those involving associations between novel stimuli and reward. We used intracerebral microdialysis to directly sample extracellular dopamine in the human amygdala during the performance of cognitive tasks. The initial transition from rest to either a working memory or a reading task was accompanied by significant increases in extracellular dopamine concentration of similar magnitude. During a sustained word paired-associates learning protocol, increase in dopamine release in the amygdala related to learning performance. These data provide evidence for sustained activation of the human mesolimbic dopaminergic system during performance of cognitive tasks.

  [source: Nature Neuroscience, Vol. 4, No. 2.]

  We used a newly developed dynamic molecular imaging technique to determine whether striatal dopamine is released during performance of a sequential learning task. In this study we localized striatal regions where dopamine receptor ligand (11C-raclopride) was displaced from receptor sites, during performance of a motor sequence learning (serial reaction time) task. The results suggest that the task induces release of endogenous dopamine in the posterior two-third of dorsomedial aspect of left putamen and the anterior part of the body of caudate bilaterally. The activations of the left putamen and the right caudate coincided with the activations observed earlier during performance of a motor planning task. Since these activations are associated with the selection and execution of a response, the activation in the left caudate, which was not observed in motor planning, is probably associated with the detection of a change in the ‘context’, and in the formulation of a new ‘rule’. Thus, the results suggest that sequential learning involves two striatal dopaminergic mechanisms, one for the detection of a change in context, and the other for selection and execution of the response.

  [source: nih.gov]

  The neurons that produce dopamine in response to pleasure often seem to activate just before the pleasurable activity occurs, which suggests that the relationship between pleasure and dopamine may be complex. The data on the timing of dopamine release are somewhat contradictory, but the theory emerging is that the dopamine reward signal acts as a kind of teaching tool. In this model, our brains release a certain amount of dopamine as a predictor of how pleasurable some activity is going to be. The dopamine motivates us, increasing our energy and drive and compelling us to engage in the pleasurable activity. If everything is as nice as the brain predicted, dopamine levels remain elevated. If things turn out even better than the brain hoped, dopamine levels are increased; we engage in the pleasurable activity even more vigorously. If, on the other hand, the activity is less pleasurable than we thought it would be, dopamine levels plummet.

  Interestingly, learning can cause dopamine responses to transfer from primary rewards (such as tuna fish to your cat) to reward-predicting stimuli (such as the sound of the can opener). This suggests that reward in general, and the dopamine hypothesis in particular, may play a central role in how and why we are able to learn.

  [source: brainconnection.com]
  

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