Brain sectioning. H0: the horizontal zero plane. A35, A30, A25, A20, A15, A10, A5, and 0 show transverse planes at 35, 30, 25, 20, 15, 10, 5, and 0 mm rostral to the interaural line, and P5, P10, P15, and P20 show transverse planes at 5, 10, 15, and 20 mm caudal to the interaural line, respectively. The nuclei and areas identified include the nuclei or areas to be observed were the caudate nucleus (CAU), the nucleus accumbens (ACB), the septal nucleus (SN), the paraventricular nucleus of the hypothalamus (PVH), the ventromedial nucleus of the hypothalamus (VMH), the arcuate nucleus (ARC), and the amygdala (AMY), the nucleus habenula (HB), the periaqueductal grey (PAG), the parabrachial nucleus (PBN), the locus coeruleus (LC), the nucleus raphe magnus (NRM), the gigantocellular reticular nucleus (GI), and the nucleus tractus solitarius (NTS).