The Swartz Center for Computational Neuroscience

Institute for Neural Computation

University of California San Diego

presents a lecture by

Joydeep Bhattacharya

Cal Tech

Shadows of Artistry  -- Neuronal synchronization during perception of music and visual art and spontaneous imagery

Thursday 28 February 2002 at 12 Noon

Room 003 Cognitive Science Building

UCSD

What goes on in our brain when listening to music? Why does someone prefer Beatles to Beethoven? How do we draw paintings on mind's canvas? What is the neurological concomitant of training in professional arts? Scientists have pondered these questions over decades but human cognitive neuroscience is still in its childhood, however, awaiting for powerful tools to measure the minute details of the complex neurocognitive processes. One of the principal
questions in this context is how the brain operates with simultaneous interaction between convergent (integrated) and divergent (differentiated) neuronal assemblies in a synchronized and fast manner.

In this talk, these issues are addressed by analysing multivariate EEG signals obtained from human subjects belonging to several broad groups - professional musicians, professional
artists, and control - while performing various tasks: listening attentively to various pieces of music, listening to neutral text, mental rotation of objects, perception and imagery of visual arts, mental creation of paintings etc. Several new measures, phase synchrony, similarity index etc., based on the concept of synchronization between nonlinear noisy/chaotic systems were applied.

During music perception, musicians showed consistently higher gamma band (> 30 Hz) synchrony over distributed cortical regions as compared with controls, yet no significant differences were found between two groups during text-processing. Synchronization  in low frequency bands (theta and delta) were found to be significantly enhanced in professional artists during imagery of visual art as well as during spontaneous mental drawings; further, similar topographical networks were found during perception and imagery of visual art.

These results suggest that professional training in music or in art is able to elicit context-sensitive dynamical correlations between multiple cortical regions and it is indeed possible to detect such hidden co-operation by the application of nonlinear signal processing techniques