Abstract: | From 192 neurons, recorded in the frontal cortex of dogs trained for differential classical conditioning of salivary reflex, 24 cells were identified related to the detection of matching-mismatching conditioned and unconditioned stimuli (CS and US) to internal set. Impulse reactions of the 1-st group of neurones (11 cells) to US disappeared, when any deviation from standard pattern of CS-US pairing occurred or when US characteristics were suddenly changed. These reactions developed again at the 3-5th repeated presentation of the stimuli delivered in "new" regime. Neurones of the 2-nd group (13 cells) were activated in response to CS only when two sequential CSs had different meaning. The 1-st group of neurones is considered as detectors of matching, and the 2-nd group--as detectors of mismatching the stimulus to its neural model, formed by mechanism of reinforcement. |