Ghrelin is a peptide hormone produced and secreted in the stomach. Numerous 
studies over the past decade demonstrate its importance in food intake, 
body-weight regulation and glucose homeostasis. These effects are driven largely 
by the high expression of the ghrelin receptor (GHSR1a) in the hypothalamus. 
However, GHSR1a is also expressed in numerous extra-hypothalamic neuronal 
populations, suggesting that ghrelin has physiological functions besides those 
involved in metabolic functions. In this review, I focus on increasing evidence 
that ghrelin has important roles in extra-hypothalamic functions, including 
learning and memory, reward and motivation, anxiety and depression, and 
neuroprotection. Furthermore, I discuss how the recently demonstrated role of 
ghrelin in promoting survival during periods of caloric restriction could 
contribute to its inherent neuroprotective and neuromodulatory properties.