Correlation analysis of units recorded in the cat dorsal lateral geniculate nucleus

Abstract

Spike activity was simultaneously recorded from pairs of units consisting of both optic tract fibers and relay cells in the cat dLGN. The unit pairs were classified with regard to the types of receptive fields involved, the relative location of receptive fields, and their occular drive. Statistical dependencies between the discharge patterns of the simultaneously observed units were assessed by computing their auto- and crosscorrelogram during a period of maintained discharge. Two distinctly different types of statistical dependence were observed. Unit pairs having like and overlapping receptive field centers exhibited statistical dependencies manifested in their crosscorrelograms by a peak near the origin. Conversely, unit pairs having opposite and overlapping receptive field centers were characterized by a prominent valley in their crosscorrelograms near the origin. These statistical dependencies are inferred to represent functional interaction most probably occurring in the retina and characterized by a common element exerting an influence on both units.

The spatial distribution of synchronization of intercostal motoneurones in the cat

“…Other authors have reported that cross-correlation peaks are strongest when the two neurones concerned are anatomically close, for instance when both are recorded by a single electrode (Noda & Adey, 1970; Arnett, 1975;Vachon & Duffin, 1978;Arnett & Spraker, 1981;153 P. A. KIRKWOOD AND OTHERS Feldman et al 1980). In some cases there was an obvious functional significance attached to the occurrence of strong peaks.…”

“…In some cases there was an obvious functional significance attached to the occurrence of strong peaks. For instance, Arnett (1975) and Arnett & Spraker (1981) only found significant peaks for the lateral geniculate or retinal ganglion cells when their receptive field centres overlapped. On the other hand, for Noda & Adey (1970) and for Feldman et at.…”

Variations in the time course of the synchronization of intercostal motoneurones in the cat

“…The interpretation that broad peaks such as these originate in presynaptic synchronization is not new (e.g. Arnett, 1975;Arnett & Spraker, 1981;Sears & Stagg, 1976), but the separation of the effects of the different inputs by the experimental manipulations we have employed here has not been achieved before. The nearest compatible results are those of Noda, Manohar & Adey (1969) and Noda & Adey (1970), who demonstrated large changes in the strength of synchronization of neurones in the hippocampus and the association cortex, respectively, with different behavioural states of unanaesthetized cats.…”

Dynamics of Stimulus-Evoked Spike Timing Correlations in the Cat Lateral Geniculate Nucleus

“…Second, when correlated firing does occur, does it exhibit time-dependent variations under stationary stimulus conditions, and how do the correlations vary with changes in neuronal firing rates? Because synchrony in the LGN often appears in the form of phase-coupled oscillations in the high gamma frequency range (60 -100 Hz) (Arnett 1975;Ghose and Freeman 1992;Laufer and Verzeano 1967;Neuenschwander and Singer 1996), we also characterized the incidence and properties of oscillatory activity in our data. Moreover, previous studies have shown robust and stimulus-dependent spike timing correlations in the…”

“…Second, when correlated firing does occur, does it exhibit time-dependent variations under stationary stimulus conditions, and how do the correlations vary with changes in neuronal firing rates? Because synchrony in the LGN often appears in the form of phase-coupled oscillations in the high gamma frequency range (60 -100 Hz) (Arnett 1975;Ghose and Freeman 1992;Laufer and Verzeano 1967;Neuenschwander and Singer 1996), we also characterized the incidence and properties of oscillatory activity in our data. Moreover, previous studies have shown robust and stimulus-dependent spike timing correlations in the LGN (Alonso et al 1996Arnett 1975;Doty and Kimura 1963;Ghose and Freeman 1992;Laufer and Verzeano 1967;Neuenschwander and Singer 1996), but these studies have largely relied on conventional methods of analysis that limit the evaluation of the time dependence of correlated firing (Gray et al 1989;Perkel et al 1967;Toyama et al 1981;Ts'o et al 1986).…”