Temporal information processing and hippocampal function

Abstract

Time is crucial for everyday activities in organisms. Timing and time perception are fundamental to survival in animals. The neural mechanisms of timing in the brain have not yet been clarified. This article reviews the relationships between temporal information processing and the functions of the hippocampus. The electrical local field potentials (LFP) in the hippocampus show obvious, rhythmic activity dependent upon training or behavioral situations, exemplified by the well-known hippocampal theta wave. Hippocampal theta is comprised of synchronous spike times of hippocampal pyramidal cells, and is indicative of a specific function in the hippocampus for that training condition. Many studies have discussed hippocampal function in spatial processing. Here, I discuss non-spatial, stimulus discrimination tasks, including temporal processing. Hippocampal theta increases as the time of a reward approaches. The basal ganglia also serves as a conductor of information flow, allocating attention and mediating the relationship between information control and hippocampal function. (Japanese Journal of Physiological Psychology and Psychophysiology, 26 (1) : 17-26, 2008.)