What does the medial septum do for the hippocampus? · Grey Matter

The medial septum sends cholinergic and GABAergic fibres through the fornix to the hippocampus and acts as the pacemaker of its theta rhythm, a 4 to 10 Hz oscillation present when an animal explores or attends.

What does the medial septum do for the hippocampus?

The medial septum sends cholinergic and GABAergic fibres through the fornix to the hippocampus and acts as the pacemaker of its theta rhythm, a 4 to 10 Hz oscillation present when an animal explores or attends. Theta organises the timing of hippocampal firing, including the sequences of place cells, and lesions or inactivation of the medial septum abolish it and impair spatial memory. The septum thus gives the memory system a clock, while the lateral septum carries the hippocampus's output toward the hypothalamus.