RESUMO
Background activity recorded extracellularly from the caudate nucleus neurons was analyzed in immobilized cats. Experimental data processing included the plotting of average frequency curves, interspike interval histograms, intensity functions, correlograms and association histograms. The frequency of the background activity in different caudate neurons varied from 0.5 to 20 imp/s and could change in the same neuron in different time intervals. According to the time structure and statistical parameters the background activity of the caudate neurons was classified in two types: unitary and group. Transformation from one type to the other could be observed in the same neuron. The obtained data do not allow considering the background activity of the caudate neurons as simple random pulse trains.
