Current events
Date: Jan 6th
Time: 09:30 am
Place : 2nd Floor Conference Room, Gonda building.
Title : "Practice makes perfect: defining the role of inhibition in vision and sensory learning."
Speaker: Sandra Kuhlman, Ph.D.
GABAergic inhibition is a key mediator of experience-dependent plasticity during postnatal development, and accumulating evidence identifies aberrant GABAergic function in schizophrenia and autism. However, the mechanisms by which inhibition regulates plasticity and learning in-vivo are largely unknown, and by extension it is not well understood how disturbance of cellular signaling pathways within inhibitory interneurons impacts cortical function in-vivo. Using in-vivo targeted electrophysiological recording of an identified inhibitory interneuron cell type, the parvalbumin (PV+) fast-spiking GABAergic interneuron, we found that visual experience uniquely broadens orientation tuning of PV+ interneurons at a time during development when excitatory neurons become more sharply tuned (Kuhlman et al., Nature Neuroscience 2011). Furthermore, we found that inhibitory broadening precedes binocular matching of excitatory orientation tuning, thus establishing that maturation of the recruitment of inhibition is a candidate for initiating binocular plasticity of excitatory neurons during the critical period. These results highlight the need for designing treatment strategies to rescue recruitment of PV+ interneurons in disease, thereby expanding the existing focus which is to enhance GABAergic synaptic output.
Perceptual learning is a progressive process of skill acquisition in which neural response properties are re-shaped by experience, even at the earliest stages of sensory processing. Thus, the very perception of the environment which informs motor output and behavioral action is itself modified during learning. How does recruitment of inhibition regulate sensory learning? Using techniques described above in combination with recent advances in head-fixed mouse behavior, this is now a tractable question in mice. I will outline a strategy to define the unique roles of specific inhibitory interneuron subclasses during ‘practice’, a.k.a. progressive learning.
