Figure 3. Examples of gap responses in auditory cortical neurons.

We categorized cells into 3 types based on their gap responses.

A) A Gap Termination Response (GTR) is a burst of firing following the end of the gap, a type of On response (black arrow). Cells with GTRs were categorized as GTR cells. Gaps are indicated by gray shading. Each row is a different gap duration (indicated at left in ms), aligned to gap termination. This example cell showed only a GTR.

B) This cell showed both an Off response to the beginning of the silent gap (e.g., grey arrow), and a GTR to the resumption of noise at the end of the gap (e.g., black arrow). This cell was categorized as both an Off cell and a GTR cell.

C) This cell showed an Off response, and was categorized as an Off cell. Because the Off response carried over into the post-gap interval (black arrow), this cell was also categorized as a GTR cell.

D) This cell showed both a GTR (black arrow) and significantly suppressed firing during the post-gap interval with longer gap durations (asterisk). Because of the GTR, this cell was categorized as a GTR cell and not a Rate Decreasing Response (RDR) cell.

E) This cell showed significantly suppressed firing during the post-gap interval (asterisk) and was therefore categorized as an RDR cell.