| Abstract: | A comparative study of single unit activity in frontal cortex and periaqueductal gray (PAG) was carried out in dogs during classical conditioning. Three types of neuron reactions were identified: on-off responses to a conditioned stimulus and to the reward presentation, tonic responses during the conditioned stimulus and tonic responses to food reinforcement. The distribution of neuron responses in structures under study proved to be different. The neurons responding tonically during feeding were 2 times more frequently encountered in PAG than in the frontal cortex, on the other hand, the percentage of neurons with phasic on-off responses was 2 times higher in the frontal cortex than in PAG. A conclusion is made that the genesis of different types of responses was determined by different inputs to cortical neurons. During feeding some neurons in PAG and frontal cortex were activated from the common source. |
