Abstract
•Task-related integrated firing of prefrontal cortical minicolumns in behaving primates performing a rule-based cognitive task is reported for the first time.•Supra-granular layers of prefrontal cortex integrate spatial information while both supra- and infra-granular layers and striatum reflect executive selection within the cognitive task.•Glutamate recording from prefrontal cortical layer 2/3 from nonhuman primates.•Neural prosthetic tapping into inter-laminar prefrontal microcircuits will assist patients with cortical (i.e. mini-columnar) disruption resulting from severe brain disorders.
The mammalian prefrontal cortex known as the seat of high brain functions uses a six layer distribution of minicolumnar neurons to coordinate the integration of sensory information and the selection of relevant signals for goal driven behavior. To reveal the complex functionality of these columnar microcircuits we employed simultaneous recordings with several configurations of biomorphic microelectrode arrays (MEAs) within cortical layers in adjacent minicolumns, in four nohuman primates (NHPs) performing a delayed match-to-sample (DMS) visual discrimination task. We examined: (1) the functionality of inter-laminar, and inter-columnar interactions between pairs of cells in the same or different minicolumns by use of normalized cross-correlation histograms (CCH), (2) the modulation of glutamate concentration in layer 2/3, and (3) the potential interactions within these microcircuits. The results demonstrate that neurons in both infra-granular and supra-granular layers interact through inter-laminar loops, as well as through intra-laminar to produce behavioral response signals. These results provide new insights into the manner in which prefrontal cortical microcircuitry integrates sensory stimuli used to provide behaviorally relevant signals that may be implemented in brain computer/machine interfaces (BCI/BMIs) during performance of the task.
