When planning goal-directed movements, the brain must integrate
sensory information from many different sources. In the case of
reaching movements to visual targets, subjects must integrate visual
target information with visual as well as proprioceptive information
about the arm. My current research in the laboratory of Dr. Philip Sabes is focused
on how vision and proprioception are combined to estimate the arm's
position during motor planning. To address this question, we use
a virtual reality environment to alter the visual feedback that subjects
receive from the arm prior to reach onset, thereby dissociating the visual
and proprioceptive signals used in the planning process. By performing
quantitative, model-based analyses of the errors caused by such manipulations,
we can infer the mixture of visual and proprioceptive information used at
different stages of motor planning. I am currently working on several
projects exploring how sensory integration is affected by sensory noise and
by the computational demands of the task being performed.
Recovery of function and cortical network modelling
(Publications/Abstracts)
Damage to the cerebral cortex (such as that caused by stroke) can
lead to profound behavioral and cognitive impairments. Equally dramatic,
however, is the recovery sometimes seen in the weeks and months following
such damage. I have worked on several projects modelling the acute
changes in cortical information
processing that follow the destruction of a small portion of the cortical
network. The goal of these studies was to understand the impact
of focal lesions on sensory receptive fields and to use these data both
to understand the perceptual deficits that follow some strokes and to explore
possible neurorehabilitative strategies.
