THE broad diversity of discharge correlates of hippocampal neurones ha
s provoked controversy. For example, purported behavioural correlates
could, instead, be location selectivity (of 'place cells') that is sec
ondarily modulated by sensory stimulation or ongoing movements. In rat
s trained to perform identical behaviours in four corners of a symmetr
ical arena, we found hippocampal pyramidal cells discharged selectivel
y as the rats performed task-related behaviours regardless of spatial
location. Since the ensemble of these hippocampal neurones comprehensi
vely represented all stages of the task, we propose that each cell rep
resents an element of the temporal organization of the animal's behavi
our, complementing the place cell representations of elements of the s
tructure of the environment.