Statistical properties of neurons in the rat mesencephalic reticular formation.

Abstract

Abstract This paper presents statistical analyses of spontaneous neuronal spike trains recorded from 26 single neurons and 9 simultaneously recorded pairs of neurons in the mesencephalic reticular formation of the rat. The single cells are divided into two categories on the basis of the overall shape of their autocorrelation histograms: Those of the so-called ’typical’ cells display an initial period of subdued firing and a more or less pronounced peak followed by a gradual decay superimposed upon which there may or may not be a low-level rhythmicity. Seventy percent of these cells exhibit a clear low-level rhythmicity including some 55% which exhibit a rhythm with a period 0.640 or 1.30 sec. The so-called ’special’ cells exhibit some pronounced temporal peculiarity quite distinct from the general pattern of the regular cells. These include cells which fire highly similar bursts of spikes at more-or-less regular intervals, and one clock-like cell which fires extremely regularly at intervals of 0.640 sec. Generally, in all cells, the fast or moderate rhythms tend to die out after several recurrences, whereas the slow rhythms seem to be sustained indefinitely. Cross-correlation histograms indicate complete independence in 4 of 9 pairs of neurons, slow rhythmic interdependence in 4 other pairs, and a strong fast interdependence in one pair.