Yorkshire Philosophical Society

Event Information

Reading the brain: seeing brain mechanisms

Professor Tony Morland

Department of Psychology, The University of York

Report
by Peter Hogarth

What does the brain do, and where? Until recently, investigation was largely limited to the study of brain malfunction following strokes or war wounds, and post-mortem details of the physical damage. New methods, particularly functional Magnetic Spin Resonance (fMRI) have made possible the continuous monitoring of brain activity in live, conscious subjects.

Incoming sensory information is directed to specific locations of the brain. When light falls on a particular spot on the retina, activity increases at a matching location within the brain. In this way, the left visual field maps onto the right visual cortex, a thin sheet of cells at the back of the right side of the brain. Several ‘visual maps’ deal with different visual features, such as colour or movement. If the retina is damaged so that part of a visual map no longer receives incoming information, the cortex reconfigures itself so that the cells in question are reassigned. This functional remodelling of the map is quite rapid if the lesion is congenital, but appears not to take place in adults.