nucleus and mediodorsal thalamic nucleus. Other axons arising from these cells descend through the medial forebrain bundle to terminate in a region dorsal to the interpeduncular nucleus. The lateral septum is a relay center for connections from the CA3 of the hippocampus to the ventral tegmental area. These connections help link reward signals with the context in which they occur. Fibers from the most lateral part of the ventral septum (i.e., bed nucleus of the anterior commissure) project through the stria terminalis to the ventral subiculum. In addition, cells located in the horizontal limb of the diagonal band project massively to the pars posterior of the medial mammillary nucleus, the ventral tegmental area, and amygdala. Functions of the lateral septum The lateral septum and movement and reward The lateral septum is involved in a variety of functions, including emotional, motivational, and spatial behavior. It has been suggested that the LS may regulate interactions between the hippocampus and other regions that mediate goal directed behavior, such as the ventral tegmental area. Firing of LS neurons is modulated by both speed and acceleration and spatial location, and that firing is also related to reward and context. It has thus been suggested that the lateral septum may incorporate movement into the evaluation of environmental context with respect to motivation and reward. Lateral septum and social behavior Inhibitory GABA, and excitatory glutamate, which regulate lateral septum (LS) activity, have been found to be increased during social play in juvenile rats. No sex differences were found in extracellular GABA concentrations during social playing, however, glutamate plays a major role in female social playing. When glutamate receptors are blocked in the LS pharmacologically, there is a significant decrease in female social playing, while males had no decrease in playing. This suggests that in the lateral septum, GABA neurotransmission is involved in social play behavior regulation in both sexes, while glutamate neurotransmission is sex-specific, involved in regulation of social play only in female juvenile rats. Lateral septum and reproduction Experiments have shown that both testosterone and dihydrotestosterone, when implanted directly into the lateral septum of male rats, caused a significant rise in serum LH and FSH levels, while not significantly increasing serum testosterone and dihydrotestosterone levels respectively. This indicates that the effect is occurring through testosterone receptors and independently of conversion to estrogen via aromatization. As of now, it is unclear, what exact pathway is mediating this