Properties of the Internal Clock^a

TLDR

The internal clock’s pacemaker rate can be altered by drugs, diet, and stress, and multiple switch‑accumulator modules are required to process simultaneous intervals, though the timing process is not always engaged. The mechanism involves a latency‑controlled switch operating in run, stop, and reset modes, an accumulator that counts absolute units, working memory that can be reset, a multiplicative conversion to reference memory influenced by drugs, lesions, and individual differences, and a comparator that evaluates the ratio between accumulator (or working memory) and reference memory.

Abstract

Evidence has been cited for the following properties of the parts of the psychological process used for timing intervals: The pacemaker has a mean rate that can be varied by drugs, diet, and stress. The switch has a latency to operate and it can be operated in various modes, such as run, stop, and reset. The accumulator times up, in absolute, arithmetic units. Working memory can be reset on command or, after lesions have been created in the fimbria fornix, when there is a gap in a signal. The transformation from the accumulator to reference memory is done with a multiplicative constant that is affected by drugs, lesions, and individual differences. The comparator uses a ratio between the value in the accumulator (or working memory) and reference memory. Finally, there must be multiple switch-accumulator modules to handle simultaneous temporal processing; and the psychological timing process may be used on some occasions and not on others.