Recent research has provided strong evidence of an identified area of the brain associated with the control of hunger. Unexpectedly this area is in the cerebellum – the anterior deep cerebellar nuclei – aDCN. Until recent years the role of the cerebellum, at the base of the brain, was thought only to assist with coordination of movement. It is now known to have a wider role in cognition, emotion and behaviour – incidentally including laughing.
People with a rare genetically determined disorder: Prader-Willi syndrome, never feel they have eaten enough, never feel ‘full’ or satiated. They tend to eat at any time and at any opportunity which, can, of course lead to life threatening obesity among other major problems. Functional MRI brain imaging studies, carried out many years ago, showed that people without Prader-Willi syndrome when viewing images of food showed more activity in the aDCN area when fasting than they did after eating. People with Prader-Willi syndrome did not show this reduction in aDCN activity after eating. Recent research in mice – international, multi-author and published in ‘Nature’ identified the mechanism behind this association of ‘satiation’ with reduction in the activity of the aDCN: activation of the aDCN of mice causes them to stop eating, apparently by progressively reducing the ‘reward’ (via dopamine release) associated with eating.
Clara Lenherr* described this nicely: “The cerebellar neurons worked by reducing the reward value of food, essentially making each mouthful less satisfying than the last”.
Hopefully these findings could lead to interventions which could help people with Prader-Willi syndrome, perhaps also some people with FrontoTemporal Dementia who have very similar difficulties, and even possibly obese people without abnormalities of brain function as well as people with eating disorders such as Anorexia, Bulimia and Night Eating Syndrome.
*Your Brain’s Natural Calorie Counter – University of Edinburgh Science Media (eusci.org.uk)
The research is reviewed in Scientific American February 2022:
https://www.scientificamerican.com/article/how-the-brain-curbs-overeating/