An interactive toolset for characterizing complex neural systems

Abstract

A set of two computer programs is described which enable the following functions: 1. (1) High-speed data acquisition from up to eight recording channels with presentation of uniform or quasi-random stimulus trains on one or two stimulus channels. 2. (2) On-line computation and display of averaged responses on all recording channels evoked by both stimulus channels. 3. (3) Computation and display of averaged evoked potentials and functional power series (FPS) through third order for characterization of system nonlinearities. 4. (4) Computation and display of stimulated responses to arbitrarily selected stimulus trains using a previously computed FPS. Both programs are implemented in FORTRAN, include on-line help, interactive and batch processing facilities and produce extensive graphics output according to the Tektronix 4010 protocol. Their initial implementation was on an LSI-II microcomputer using TSX + extensions to RT11. Additional capabilities and speed have been gained by porting the analysis routine to the Apollo workstation environment. To date these programs have been used to study the following: 1. (1) The somatosensory system in the human using dual random trains presented to the median and ulnar nerves. 2. (2) Cognitive processing in the human (normals and first-break schizophrenics) using both uniform (P300 paradigm) and dual random trains of tone bursts with the subject either counting or pressing a lever in response to tones with a specific pitch. 3. (3) The network properties of the rabbit hippocampus (both in vivo and in vitro preparations) using random train simulation of the intrinsic pathways.