A simultaneous temporal processing account of response rate.

The goal was to determine whether a signal (e.g., a click) at food availability affects timing behavior in rats. Twenty-four rats were trained on an appetitive lever-press procedure that varied on two dimensions: shape of the interreinforcer distribution (i.e., fixed-interval 60s or random-interval 60s) and number of signals (i.e., the presence or absence of a click at the time of reinforcer availability). The rats were randomly partitioned into one of four groups (each group had six rats): Fixed, Signaled-Fixed, Random, and Signaled-Random. The shape of the interreinforcer distribution affected the response pattern; the presence of the click affected response rate. These results provide support for a simultaneous temporal processing account of behavior. Copyright (c) 2009 Elsevier B.V. All rights reserved.