title: Tracking the changes of hippocampal population nonlinear dynamics in rats learning a memory-dependent task.
abstract: Neurobiological processes associated with learning are known to be highly nonlinear, dynamical, and time-varying. Characterizing the time-varying functional input-output properties of neural systems is a critical step to understand the neurobiological basis of learning. In this paper, we present a study on tracking of the changes of neural dynamics in rat hippocampus during learning of a memory-dependent delayed nonmatch-to-sample (DNMS) task. The rats were first trained to perform the DNMS task without a delay between the sample and response events. After reaching a performance level, they were subjected to the DNMS task with variable delays with a 5s mean duration. Spike trains were recorded from hippocampal CA3 (input) and CA1 (output) regions during all training sessions and constitute the input-output data for modeling. We applied the time-varying Generalized Laguerre-Volterra Model to study the changes of the CA3-CA1 nonlinear dynamics using these data. Result showed significant changes in the Volterra kernels after the introduction of delays. This result suggests that the CA3-CA1 nonlinear dynamics established in the initial training sessions underwent a functional reorganization as animals were learning to perform the task that now requires delays.
authors.affiliation: Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, USA. homchan@usc.edu
authors.forename: Rosa H M
authors.initials: RH
authors.lastname: Chan
authors.forename: Dong
authors.initials: D
authors.lastname: Song
authors.forename: Anushka V
authors.initials: AV
authors.lastname: Goonawardena
authors.forename: Sarah
authors.initials: S
authors.lastname: Bough
authors.forename: John
authors.initials: J
authors.lastname: Sesay
authors.forename: Robert E
authors.initials: RE
authors.lastname: Hampson
authors.forename: Sam A
authors.initials: SA
authors.lastname: Deadwyler
authors.forename: Theodore W
authors.initials: TW
authors.lastname: Berger
mesh_terms: D000200:Action Potentials; D000818:Animals; D006624:Hippocampus / Q000502:physiology*; D008568:Memory; D051381:Rats; D013647:Task Performance and Analysis