Cerebellum a variant of Guillain–Barré syndrome. The human cerebellum changes with age. These changes may differ from those of other parts of the brain. The cerebellum is the youngest brain region (and body part) in centenarians according to an epigenetic biomarker of tissue age known as epigenetic clock: it is about 15 years younger than expected in a centenarian. Further, gene expression patterns in the human cerebellum show less age-related alteration than that in the cerebral cortex. Some studies have reported reductions in numbers of cells or volume of tissue, but the amount of data relating to this question is not
Hypothalamus amygdala and septum, and is also connected with areas of the autonomous nervous system. The hypothalamus receives many inputs from the brainstem, the most notable from the nucleus of the solitary tract, the locus coeruleus, and the ventrolateral medulla. Most nerve fibres within the hypothalamus run in two ways (bidirectional). Several hypothalamic nuclei are sexually dimorphic; i.e., there are clear differences in both structure and function between males and females. Some differences are apparent even in gross neuroanatomy: most notable is the sexually dimorphic nucleus within the preoptic area, in which the differences are subtle changes in the connectivity and