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The success of two monkeys in performing an eye-head-hand coordination task was investigated during the Bion 11 flight. In comparison to the ground controls, it took the flight monkeys more time to reach the light stimuli located at 40 degrees to the left or right from the center of the panel in front of them. During flight days (FD) 5-6, the precision of hand movements deteriorated, and during FD 7-14, it improved, although the performance time increased.

Cross-interval and cross-correlation analysis of neuron activity was used to study cell interactions in the cerebellar vermis of conscious rabbits. The cross-correlation method, based on post-synaptic potentials (PSP) from one member of a pair of neurons, supplements the cross-interval analysis used for evaluating the interactions of neurons in terms of action potentials. A total of 16 neuron pairs were analyzed, in which the activity of one neuron was recorded intracellularly and that of the other extra- or intracellularly. Interactions were observed in 10 pairs. Most pairs showed inhibitory interactions. Pairs with inhibitory interactions included those in which the activity of one or both neurons contained complex spikes. Also of interest was the analysis of connections in which influences were excitatory in one direction and inhibitory in the other. In these cases, neuron discharges were invariably simple spikes. Variability and plasticity in the output signals of Purkinje cells were greater than the variability and plasticity of the common inputs to Purkinje cells.

The postsynaptic changes in the focal potentials of the sensorimotor cortex of the awake rabbit was investigated in this study following tetanization of the corpus callosum and the white matter. Stimulation of these structures was carried out during testing. A prolonged (hour-long) increase in the amplitude of the responses was observed in some of the experiments following tetanization, as compared with the control prior tetanization. Just as long a decrease in the amplitude of the responses tested developed in a number of experiments in the posttetanic period. It was concluded that prolonged plastic changes can occur in different directions in the sensorimotor cortex of the awake rabbit.