Personality and the Brain, Part 7

Music is my day-long obsession, joy and torment

Posted Oct 23, 2016

Science Channel, used with permission
Source: Science Channel, used with permission

In the fall of 2015 I invited acquired savant Derek Amato to my lab in Miami. One of the things we wanted to examine was whether his personality changes and newfound talents were related to attention. Part of the change we observed in his personality was a change in what grabs his attention. As a salesperson and a sports fanatic prior to his accident, music was something that played in the background in malls or perhaps marked a notable sports event. After his injury music literally draws his attention away from other tasks he has to perform.

We tested Derek’s obsession with music, particularly the piano, by using a special attention bias test that has been used to indicate addiction. The test feeds off of what is known as the Stroop test. In the original Stroop task, subjects are asked to name the ink color of a series of color words as fast as they can in two conditions. In the experimental condition color words are printed in an incongruent ink color. For example, the color word ‘red’ is printed in green’ and the color word ‘blue’ is printed in 'red’. In the control condition, the color words are printed in black or a congruent color. For example, ‘red’ is printed in black or red.

Kristian Marlow, used with permission
Source: Kristian Marlow, used with permission

Studies consistently show that subjects name the ink color of color words printed in congruent colors significant faster than the ink color of color words printed in incongruent colors. The main explanation for this is that the meaning of the color words divert the subjects’ attention away from the task they are supposed to engage in. Stroop-like tasks have been created to test for a diversion of attention, also known as attentional bias, in subjects with depression, an addiction to drugs or alcohol, an eating disorder and suicidal tendencies.

To test Derek’s attentional bias we created a similar test with words with meanings related to music and neutral words. The musical words included words such as “chord,” harmony, “scale,” timbre,” “symphony” “hammer, whereas the neutral words included words like “plane,” “pillow”, “glass,” “little”, “sympathetic,” family,” and “thinking.” The musical words and the neutral words were presented in different colors. Each musical word was similar to a neutral word in length, how frequently it occurs in the English language, the color it was printed in and its location on the page. The task for Derek was to name the ink color of each of the words on the list of musical words and then name the ink color of each of the words on the list of neutral words. The test revealed that it took him significant longer to name the ink color of the words on the list of musical words compared to the words on the list of neutral words. The explanation for this delay is that the musical connotation of the music words grabbed his attention and distracted him from the task of naming the ink color. This indicates an almost addictive obsession with music, which appears to be what underlies the shift in artistic interest.

We also looked at images of Derek’s brain using regular MRI. The images revealed multiple brain regions with permanent dead tissue, which showed up as gray spots on the images. One of the areas of Derek’s brain that had been knocked out in his injury was located in a part of the brain known as the right supramarginal gyrus. The supramarginal gyrus is located, roughly, at the junction of the top, side and front of the brain. This area of the brain helps us to separate our own emotional state from that of other people. When this area is completely misfiring, we can be entirely mistaken about the emotions of other people, and this can lead to a lack of empathy because we are projecting our own emotions onto others. This can distort our understanding of other people's emotions, in particular if they are completely different to our own. But when the activity in this area is only partially impaired, the impairment can lead to a kind of projection of our own emotional state onto others but without the distortion. A disruption of this brain region may, in fact, be what underlies mirror-touch synesthesia, the condition that can make people have feelings that mirror those of others.

You can read the next chapter of this true tale tomorrow. Part 6 can be found here. For further information about this and similar cases of extraordinary human ability, you can read our book The Superhuman Mind.

Penguin, used with permission
Source: Penguin, used with permission