Mechanisms of Attention in Early Visual Processing

University Of California-Davis, Davis CA

Investigators

Abstract

The sensory world is rich in information, but subjective experience and experimental demonstrations reveal that the nervous system is limited in how much of this confused mass of information it can effectively process at any moment in time. Selective attention provides a means by which organisms regulate the flow of sensory information by enhancing the processing of relevant information and inhibiting irrelevant or distracting events. Numerous studies in humans and animals have established that attentional control mechanisms influence visual information processing within the cerebral cortex. However, the neuronal mechanisms of selective attention remain poorly understood at the cellular and synaptic levels. Using a novel method for measuring the effects of attention on synaptic communication between identified neurons, Drs. W. Martin Usrey and George R. Mangun of the University of California, Davis are determining the influence of attention at the earliest stages of processing in the cerebral cortex. In so doing, they are testing several long-standing hypotheses about the spatial organization of voluntary attention, the interactions between target facilitation and distractor suppression mechanisms, the role of spatial scale in determining the locus of selection in voluntary attention, the role of thalamocortical mechanisms in reflexive attention, and the contributions of specific visual pathways to voluntary and reflexive visual attention. The project will advance discovery and understanding while promoting teaching, training, and learning through graduate and postdoctoral scholar involvement in undergraduate research supervision related to the project. Via the University of California Davis Summer Undergraduate Research Program (SURP) and the Young Scholars Program (YSP), the PI and the Co-PI will also mentor undergraduate and promising high-school students interested in pursuing careers in science. These programs promote underrepresented groups and provide research opportunities for students from non-research colleges. The project will enhance international collaboration through exchange programs. The proposed research will strongly benefit society in education and health. Because selective attention is a core cognitive process, elucidating attentional mechanisms in humans remains a high priority in efforts to understand, diagnose and treat psychiatric conditions that involve deficits in attention, including attention deficit hyperactivity disorder (ADHD), autism, obsessive compulsive disorder (OCD) and schizophrenia. Ameliorating these disorders provide increased opportunities for advancing education and human productivity.