Evoked response study tool software for single and multiple evoked potential measurements in animals.

Abstract

The Evoked Response Study Tool (EVREST) is an integrated, portable hardware/software system designed for field measurement of evoked potentials. The software component of EVREST is a Windows-based application that is used for generating and calibrating sound stimuli and recording and analyzing evoked responses. The software has been used by a number of investigators to measure auditory evoked potentials in fish, marine mammals, and primates. The software features a graphical user interface and is compatible with a variety of commercial off-the-shelf data acquisition hardware. Options for sound stimuli include arbitrary waveforms loaded from disk or sums of up to 16 individual waveform components consisting of clicks or amplitude/frequency modulated tones. Evoked response data are averaged/displayed in real-time and also streamed to disk, allowing post-acquisition changes to analysis parameters. Objective response detection procedures include the F test, magnitude-squared coherence, and phase coherence. An adaptive staircase procedure is included for automated threshold measurements at multiple frequencies. In this talk, the operating principles and capabilities of the EVREST software are reviewed and example evoked potential data from dolphins and sea lions are presented. [Work supported by ONR.]