Flexible routing of information through specialized networks in the brain
The brain comprises regions and networks devoted to selected sensory, motor and computational goals. Yet, to support sophisticated cognitive operations these regions and networks must possess a capacity to interact—to share information and pass messages.
Recent advances in systems neuroscience have elucidated mechanisms supporting information processing in specialized cortical circuits as well as their local network interactions (e.g., the face patch system) but little is known about the flexible, long range, functional connectivity that would allow information processing (e.g., face recognition) to bear on a behavioral demand (e.g., approaching an individual).
Rapid changes in functional connectivity enable us to make decisions in environments in which information-action contingencies change in unpredictable ways. Understanding the neural mechanisms that support these rapid changes in functional connectivity is likely to prove key to understanding complex behaviors.
We investigate how information can be shared between networks depending on task requirements. We designed a behavioral task in which monkeys will recognize faces and make eye movements to “choice targets” whose association with a face must be learned within seconds of exposure to the faces.
This allows us to study the interactions between specialized networks in the ventral stream, which are responsible for face perception, and dorsal stream networks, which support decision making and eye movements. These areas are not directly connected.
To identify candidate structures that mediate communication between these networks, we will use functional magnetic resonance imaging (fMRI) while monkeys perform the task (whole brain imaging survey), and we will incorporate microstimulation with fMRI to identify which of the nodes are connected.
We will then record responses from individual neurons to investigate the fine-scale exchange of information between neurons in these nodes. We will target areas identified as putative links in the processing chain from face perception to flexible decisions about those faces, to making eye movements. The experiments will reveal how neurons can ‘tune-in’ to distant neurons with useful information about the task at hand.