A Normalization Circuit Underlying Coding of Spatial Attention in Primate Lateral Prefrontal Cortex

eNeuro. 2019 Apr 15;6(2):ENEURO.0301-18.2019. doi: 10.1523/ENEURO.0301-18.2019. eCollection Mar-Apr 2019.

Abstract

Lateral prefrontal cortex (LPFC) neurons signal the allocation of voluntary attention; however, the neural computations underlying this function remain unknown. To investigate this, we recorded from neuronal ensembles in the LPFC of two Macaca fascicularis performing a visuospatial attention task. LPFC neural responses to a single stimulus were normalized when additional stimuli/distracters appeared across the visual field and were well-characterized by an averaging computation. Deploying attention toward an individual stimulus surrounded by distracters shifted neural activity from an averaging regime toward a regime similar to that when the attended stimulus was presented in isolation (winner-take-all; WTA). However, attentional modulation is both qualitatively and quantitatively dependent on a neuron's visuospatial tuning. Our results show that during attentive vision, LPFC neuronal ensemble activity can be robustly read out by downstream areas to generate motor commands, and/or fed back into sensory areas to filter out distracter signals in favor of target signals.

Keywords: attention; macaque; neurophysiology; normalization; prefrontal cortex.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / physiology
  • Animals
  • Attention / physiology*
  • Electroencephalography
  • Macaca fascicularis
  • Male
  • Neurons / physiology*
  • Patch-Clamp Techniques
  • Pattern Recognition, Visual / physiology*
  • Prefrontal Cortex / physiology*
  • Saccades / physiology
  • Space Perception / physiology*