Thomas M. Schofield

A dynamical pattern recognition model of gamma activity in auditory cortex

Authors:

  • Melissa Zavaglia

  • Ryan T. Canolty

  • Thomas M. Schofield

  • Alexander P. Leff

  • Mauro Ursino

  • Robert T. Knight

  • Will D. Penny

Date: 2012

DOI: 10.1016/j.neunet.2011.12.007

PubMed: 22327049

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Abstract:

This paper describes a dynamical process which serves both as a model of temporal pattern recognition in the brain and as a forward model of neuroimaging data. This process is considered at two separate levels of analysis: the algorithmic and implementation levels. At an algorithmic level, recognition is based on the use of Occurrence Time features. Using a speech digit database we show that for noisy recognition environments, these features rival standard cepstral coefficient features. At an implementation level, the model is defined using a Weakly Coupled Oscillator (WCO) framework and uses a transient synchronization mechanism to signal a recognition event. In a second set of experiments, we use the strength of the synchronization event to predict the high gamma (75-150 Hz) activity produced by the brain in response to word versus non-word stimuli. Quantitative model fits allow us to make inferences about parameters governing pattern recognition dynamics in the brain.