D is for Default Mode Network

| February 9, 2014

As the “Aesthetic experience” is an extremely complex phenomenon, it follows that finding a universal answer to the question “what is an aesthetic experience?” is an arduous endevour. Georege Santayana defines beauty as “the pleasure we attibute to an object”. Kant talks about taste in terms of subjectivity and universality. There is no doubt that individual preferences play a major role in determining whether (and to what extent) we find something aesthetically pleasing or not. I am wondering whether a common component exists, an aspect of subjective experiences which is shared universally amongst all aesthetic experiences. I would like us to attempt to answer this question by looking at what happens to the brain when we have a pleasurable experience with a piece of artwork.

This paper by Edward Vessel and collegues provides powerful insights on this matter; “The brain on art: intense aesthetic experience activates the default mode network” (original paper –> http://www.frontiersin.org/Journal/10.3389/fnhum.2012.00066/full).

What is the Default Mode Network?

Our thoughts are born out of the dynamic competition between external and internal stimuli. That is, they can be either triggered by  perception (e.g. of a physical object/person or situation in our surroundings) or self-generated. The default mode network, or DMN, supports the latter case. It is a neural circuit which is activated whenever our mind ventures into introspection, and deactivated whenever we turn our attention towards externally-oriented tasks.

In this experiment, participants are showed a series of paintings (see attached image) and asked to rate them from 1 to 4 based on how “moving” they found each piece. Meanwhile, their brain activity is scanned in order to visualize what parts of the brain are activated by each painting. The study found that activity in the brain region which supports sensory experience (response to external stimuli) increased linearly with ratings. However, the interesting fact was that the brain region which is activated by introspection (DMN) was an all or nothing phenomenon, i.e. it was only activated when the participant gave a maximum rating to the painting (4, most moving). These result can be interpreted in the following way; Our individual preferences may be subjective, some people may focus more on the mood of artwork while others pay more attention to the technique with which it’s produced. However, what leads us all to define something as beautiful is whether is triggers introspection (reflected in the activation of the DMN).