Recognition of egocentric and allocentric visual and auditory space by neurons in the hippocampus of monkeys.

Neuronal activity in the hippocampus was recorded in the awake monkey during presentation of visual and auditory stimuli from various directions. About 10% of the neurons coded visual and/or auditory information from unique directions. Some of these neurons were stimulus-selective, and others were not. Three types of neurons were identified by rotating the animals: egocentric and allocentric, and indeterminate. The results are consistent with a role of the hippocampus in spatial memory.