Eavesdropping on Cortical Plasticity

Seminar | June 14 | 3:30-4:30 p.m. | 125 Li Ka Shing Center

 Adi Mizrahi, The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem

 Neuroscience Institute, Helen Wills

One of the overarching goal in our lab is to understand cortical plasticity in adult circuits. This goal remains challenging because cortical neurons are functionally heterogeneous and access to specific active neurons for further experimentation is limited. In the primary auditory cortex (A1), for example, spiking responses to natural stimuli like vocalization cannot be easily predicted from their location in the tonotopic axis and even neighboring neurons vary widely in their response profiles. To parse out cortical circuits that encode specific stimuli for further experimentation, we calibrated an activity-dependent Fos-CreERT2 driver mouse (called TRAP) with different reporter systems to allow cellular labeling and genetic access of functionally active circuits in the mouse brain. We found that natural sounds are efficient in inducing genetic recombination in responsive neurons as assessed by in vivo two-photon targeted patch recordings. Using this system in combination with other methods like transsynaptic tracing, physiology and behavior, we are currently characterizing the mechanisms underlying two different phenomena – “perceptual learning” and “motherhood”. I will discuss our work (in progress) showing the unique changes in A1 (and downstream of it) in response to disparate behavioral demands while learning the meaning of new sounds.