Marlene Cohen, PhD
Department of NeuroscienceAssociate
Director, Center for the Neural Basis of Cognition
University of Pittsburgh
Host: Keren Haroush
Visual attention dramatically improves subjects' ability to see and also modulates the responses of visual and oculomotor neurons. Despite hundreds of studies demonstrating the co-occurrence of behavioral and neuronal effects of attention, the relationship between neuronal modulations and improved performance remains unknown. Two dominant hypotheses have guided previous work: that attention 1) improves the information that is encoded about the attended object or 2) improves the visual information that is communication between visual and oculomotor brain areas. By recording from groups of neurons at multiple stages of visuomotor processing, we showed that none of these hypotheses account for observed perceptual improvements. Instead, our data suggest a novel hypothesis: that the well known effects of attention on firing rates and shared response variability in visual cortex reshape the representation of attended stimuli such that they more effectively drive downstream neurons and guide decisions without explicitly changing the weights relating sensory responses to downstream neurons or behavior. In general, constraining our analyses by the animals' behavior and the simultaneous recordings can greatly clarify the relationship between cognition, neuronal responses and behavior.
 Ruff, D.A., Cohen, M.R. Simultaneous multi-area recordings suggest that attention improves performance by reshaping stimulus representations. Nat Neurosci 22, 1669–1676 (2019). https://doi.org/10.1038/s41593-019-0477-1
 A. M. Ni, D. A. Ruff, J. J. Alberts, J. Symmonds, M. R. Cohen. Learning and attention reveal a general relationship between population activity and behavior. Science 26 Jan 2018: Vol. 359, Issue 6374, pp. 463-465 DOI: 10.1126/science.aao0284