Unraveling the structure of time in the brain

Whether we are speaking, swimming, or playing the piano, we are crucially dependent on our brain?s capacity to step through sequences of neural states. Songbirds provide a marvelous animal model in which to study this phenomenon. Their stereotyped vocalizations have hierarchical temporal structure spanning two orders or magnitude in timescale ? from individual vocal gestures lasting ten milliseconds, to song syllables (~100 msec), to song motifs (~1 sec). Several brain areas have been proposed to control timing at these different timescales. By manipulating these circuits with temperature change and observing the effect on song structure, we have been able to localize a single ?clock? circuit in the premotor vocal pathway. Intracellular neuronal recordings during singing elucidate the mechanism by which this clock circuit operates. Our findings are consistent with the predictions of a synfire-chain model? a synaptically connected chain of neurons in HVC. Our findings are inconsistent with models in which subthreshold dynamics, such as ramps or oscillations, play a role in the control of timing.

Prof. Michale Fee is hosted by the students of the Department of Neurobiology, as a part of the departmental students-invited visiting scientist program.

For more details please contact Michael Yartsev: myartsev@gmail.com