A microcomputer workstation for auditory neurophysiology

Abstract

An inexpensive microcomputer-based system has been developed for fast digital synthesis of complex sound stimuli, recording of neural activity, and interactive on-line histogramming and plotting of response properties. The hardware requirements for stand-alone synthesis and spike recording capability are an Apple Macintosh II, a GW Instruments data acquisition card, and a modest amount of interfacing and signal conditioning electronics. Off-line analysis of acquired data files can be performed on any current Macintosh. Stimuli can be computed synthetic sounds or digitized natural sounds; both types are presented at sampling rates of up to 100k samples/s with concurrent timing of spikes at 10-μs resolution. The system is especially suited for experiments in which sounds must be rapidly resynthesized as a stimulus parameter is changed under manual or automatic control. A modular software design allows installation of new synthesis and analysis routines, or new drivers for alternate hardware interfaces. Synthesis parameters and raw spiketime data are saved to disk files in a format that allows exact recreation of stimuli and precise correlation of spikes with temporal features in those stimuli. [Work supported by NINCDS.]