Study of functional characteristics of brain neurons in behavioral experiment

The work of the central integrative neurons of the brain is concerned with the total evaluation of the heterogeneous signals and signals of different sensory modality, coming to these neurons via the parallel inputs. Due to the processing of this information central neurons participate in organization of the different acts of animal and in mechanisms of switching from one action to another. Therefore, to define what role the neuron plays in the behavior organization it is necessary to analyse dynamics of unit activities continuously during the all successively performed animal's actions. The traditional methods, such as post- and peristimlus histograms and crosscorrelation are not effective enough for this aim. They are useful for the analysis of the spikes that are situated close to the synchronizing signal only. The application of these methods for the study of unit activity related to extended behavioral program inevitably leads to creation of histograms for each action separately. Such sets of histogram do not reflect the real dynamics of neuronal activity corresponding to the continuum of the behavior. A complex approach is proposed for the study of neuronal correlates of behavior directed towards overcoming of the mentioned difficulties. This approach includes multicomponent behavioral program, recording o spikes in several units in parallel and analysis of unit activities in relative time scale, based on duration of each of the successively performed by the animal action. The nontraditional methods of the processing of spikes sequences are elaborated, such as relative time histograms and methods of the multivariate statistics. The realized on this principles analysis gives a full impression about neuronal activities uninterruptedly, during all stages of performance of the extended behavioral program. The described methods were approved in the experimental study of the functional characteristics of the striatal units in monkeys. The comparable data were obtained on the individual reactions of neurons and dynamics of their activities in group during the performance of behavior program. These data revealed lack of functional specialization of the striatal neurons and different forms of their involvement in the motor and cognitive functions.