Research reportThe decline in rat hippocampal theta activity during response inhibition for the compound stimulus of negative patterning and simultaneous feature-negative tasks

- We examined the relationship between the decline of theta activity and learning task.
- The decline of theta activity was observed during non-RFT of simultaneous feature negative task.
- This study showed the relationship between the decline of theta activity and inhibition response.

In experiment 1 of this study, we compared hippocampal theta activity between negative patterning and simple discrimination tasks. Our results demonstrated a transient decline in theta activity during response inhibition for a compound stimulus in the negative patterning task. In experiment 2 of this study, we compared hippocampal theta activity among simultaneous feature-negative, compound stimulus discrimination, and simple discrimination tasks in order to determine the cause of the decline in hippocampal theta activity during negative patterning tasks. Our results revealed that the decline in hippocampal theta activity occurred during the response inhibition for a compound stimulus in the simultaneous feature-negative task but not during the compound stimulus discrimination or simple discrimination tasks. Thus, we conclude that the transient decline in hippocampal theta activity is related to the inhibition in response to a compound stimulus that has an element that overlaps with a single stimulus.