Spatiotemporal Patterns of Stimulus-locked Multiunit Activity in the Auditory Cortex of the Big Brown Bat Resemble Wavelet Packet Computations

Wednesday, March 10, 1999 - 11:15am - 12:00pm
Keller 3-180
Steven Dear (Penn State College of Medicine)
Temporal synchronization of neuronal firing between cortical neurons has been proposed as a mechanism for binding different stimulus features together in perception. Evidence supporting this hypothesis is accumulating. However,one unresolved question from binding studies is can the synchronized firing of cortical neurons convey any information beyond the stimulus feature-selective properties of the individual cortical neurons? We present evidence that the stimulus-locked firing of multiple cortical neurons to biologically relevant acoustic stimuli in the big brown bat appears encode particular stimulus features using a temporal code. Furthermore, we report that the majority of stimulus-locked, multiple neuron extracellular potentials have stable waveforms that closely resemble the shapes and dyadic scaling properties of members of the Symlet wavelet packet family. These results suggest that spatiotemporal patterns of temporally synchronized cortical potentials may act as a parallel, distributed code through a mechanism computationally equivalent to wavelet packet analysis.