How does behaviorally relevant information flow through sensory cortical layers?

 

Perception depends crucially on the ability of our sensory cortical systems to select behaviorally relevant stimuli for detailed inspection while ignoring distractors. For example, neurons in the visual cortex process information about the shape and size of objects in the visual scene. These neurons are embedded within a layered (or laminar) structure in the sensory neocortex. There are stereotypical patterns of anatomical connectivity in this layered cortical architecture and these connectivity motifs are shared across sensory modalities (audition, somato-sensation etc.) leading to the idea of a canonical information processing circuit. Information processing in these laminar circuits is strongly modulated by the mechanisms of attention, which allow the flexible selection of behaviorally relevant stimuli.

 

By studying the functional dynamics of these intricate layered circuits while animals are engaged in challenging tasks, we hope to discover fundamental principles of information flow through the cortex. This will ultimately help us understand disease conditions such as ADHD and schizophrenia in which information flow is disrupted. Currently, the lab is interested in the following broad but inter-related questions:

 

What are the canonical computations in laminar cortex that support shape processing and object perception?

We are studying the laminar organization principles of shape processing in visual area V4, an area that lies at a critical juncture in mediating the transformations that occur between simple feature extraction in the primary visual cortex and the final stages of complex shape processing in the inferotemporal (IT) cortex.

What is the causal role of the laminar cortical circuit in perception?

Area V4 is also strongly modulated by the mechanisms of attention. We are investigating the causal role of laminar circuit components in perception via optogenetic interventions while animals are engaged in attention-demanding tasks.

 

How do eye movements and attention shape cortical organization and reorganization following damage?

Vision is an active sensory process in which we gather information via rapid eye-movements. This process is disrupted in disease conditions such as Macular Degeneration, which lead to central vision loss. We are studying the mechanisms of reorganization in laminar cortical circuits that accompany central vision loss.

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