Table 3

Stimulation of the pre-commissural fornix in rodents, along with main findings

Projections	Study	Model	Stimulation pattern	Main findings
All	Mamad 2015	Rats	Theta burst	Resets the spiking of hippocampal theta cells, increases theta synchronisation, entrains the spiking of hippocampal place cells
Cholinergic neurons and/or projections Optogenetic excitation	Van der Casteele et al 2014	Mice, with or without urethane anaesthesia	Sine wave, 1–12 Hz	Enhance theta rythm, suppress peri-theta frequency bands
	Dannenberg et al 2015	Mice, under urethane anaesthesia	Square pulses, 5–40 Hz	Increase firing of hippocampal inhibitory interneurons and decrease firing of principal cells Their activation is required for theta synchronisation
	Mamad et al 2015	Rats, awake	Square pulses, 8–10 Hz vs 50 Hz	The most potent effect on hippocampal theta amplitude was observed after 8–10 Hz stimulation and in a non-active behavioural state
GABAergic neurons and/or projections Optogenetic excitation	Gangadharan et al 2016	Mice, freely moving	Square pulses, 10 or 20 Hz	Enhance type 2 theta rhythm, object exploration and not open-field exploration behaviour
Glutamatergic neurons and/or projections Optogenetic excitation	Fuhrmann et al 2015	Mice, freely moving	3–12 Hz	Enable initiation of locomotion and theta oscillations as well as the active regulation of locomotion speed
	Robinson et al 2016	Mice, freely moving	4–12 Hz	MS glutamatergic neurons synchronise hippocampal theta rhythms whereas activation of their projections to the hippocampus through fornix stimulations has no effect on theta rhythms

MS, medial septum.