Saskia Haegens, Dept. of Psychiatry, Columbia University Medical Center, New York

The role of the beta rhythm in supramodal information processing

Here, we explored oscillatory dynamics in the medial premotor cortex (MPC) involved in supramodal perceptual decision-making. We recorded local field potentials (LFPs) and spikes in two monkeys trained to perform a tactile/acoustic frequency discrimination task, and studied the role of oscillatory activity as a function of stimulus properties (frequency and sensory modality) and decision outcome. We found that beta band power correlated with relevant stimulus properties: there was a significant modulation by stimulus frequency during the retention interval, as well as a modulation by stimulus modality — the latter was only observed in the case of a purely unimodal task, where modality information was relevant to prepare for the upcoming second stimulus, but not in a crossmodal paradigm. Furthermore, we found a significant modulation of beta power starting during presentation of the second stimulus, which was predictive of decision outcome. Finally, beta band spike-field coherence (SFC) matched these LFP observations. In conclusion, we demonstrate that beta power in MPC is reflective of stimulus features in a context-dependent manner, and additionally reflects the decision outcome. This information is coded in a supramodal manner — modality information is only retained when relevant for the task at hand.

Additional Information

Talk in the Colloquium Series of the GRK 1589 "Sensory Computation in Neural Systems"

Organized by

Alexander von Lautz / Felix Blankenburg