Investigating dynamic aspects of brain function in slice preparations: spatiotemporal stimulus patterns generated with an easy-to-build multi-electrode array.

Electrical stimulation of nervous tissue with single stimulating electrodes is a technique widely used for the investigation of nervous system function. While it has proved to be useful in all kinds of experiments, single electrode stimuli are, however, far from being 'natural'. In most parts of the living brain, incoming activity results from the firing of a large number of presynaptic neurons, thus reflecting a complex combination of space and time aspects of neural activity. In this paper, a multi-electrode stimulating system is introduced which allows for the generation of fast space-time stimulus patterns. An example for the application of dynamic input patterns to the cerebellar cortex in vitro is given. The corresponding experiments revealed aspects of cerebellar function which cannot be seen using static or single electrode stimulation.