STIMULATION, DATA-ACQUISITION, SPIKES DETECTION AND TIME RATE ANALYSIS WITH A GRAPHICAL PROGRAMMING SYSTEM - AN APPLICATION TO VISION STUDIES

A Macintosh-based system performs stimulus control and data acquisitio n, and an off-line analysis, in experiments on visually driven neurons in frog. The stimulus is a target moved on a modified XY recorder. Th e computer is equipped with a multifunction input/output board to perf orm stimulus control and data acquisition. The graphical programming s ystem LabVIEW 2 was used to develop the 'Vision 93' package made of 4 main 'virtual instruments' (VIs). By means of DOCS-Exp, the user contr ols the experiment via screen displays which look like front panels of electronic instruments. DOCS-Preproc performs a user-controlled spike detection and computes mean impulse rate values. DOCS-SAS displays th e instantaneous frequency, mean impulse rate, spike counts or interspi ke time intervals as staircase histograms and/or spline smoothed curve s. Finally, DOCS - x - Functions computes and graphs quantitative stim ulus/response relationships in terms of velocity, diameter, orientatio n and configuration of the target. The functionalities of these main V Is are presented and original software components are detailed. System operation is illustrated by using the successive VIs to process a sam ple signal record.