Your aging brain

Your brain is the centre of a complex control system known as the nervous system.

Together with your spinal cord your brain forms the central nervous system from which extends an extensive network of nerves which reach to every organ, tissue, and muscle in your body.

This network is referred to as your peripheral nervous system.

Your nervous system functions to control voluntary muscle which responds to external stimuli. This is known as your somatic nervous system.

Your nervous system also functions to control involuntary internal muscles such as the smooth muscles of your gastrointestinal tract and internal organs such as your stomach, liver, small and large intestines and heart.

This is referred to as your autonomic nervous system which itself has two branches: the sympathetic nervous system which responds to pain and stress, and the parasympathetic nervous system which acts during normal conditions.

Your nervous system responds to various stimuli such as heat, light, pain, hunger, and fullness with the help of hormones and neurotransmitters.

These metabolites help pass the “message” from the site of initiation to your brain which then sends a message in response that effects an appropriate action.

For instance, full digestion of a meal triggers a sequence of events which releases specific hormones which alert your brain to send signals of hunger so that you begin to seek out food.

Neurotransmitters are considered to be chemical messengers such as norepinephrine, dopamine, serotonin, neuropeptide-Y, and corticotropin-releasing agent (CRF). CRF has been identified in depressed patients and also appears to weaken feeding response.

Despite the important functions your brain and nervous system perform your brain is only 2% of your body mass.

However, for your brain to function properly it not only needs appropriate blood flow, but also adequate energy.

Your brain regulates blood flow which can be influenced by the amount of carbon dioxide (CO₂) in your blood, blood pressure, mean arterial pressure and cerebral metabolism.

How your brain functions is also influenced, positively or negatively, by your genetics, by environmental factors, and the aging process.

Aging, general health and mental decline

Declining brain function is a natural part of the aging process and normally occurs over a long period of time.

Your biological age, functional level, genetics and your environment all affect the rate at which you experience declining brain function.

Various brain processes such as memory, cognitive function, processing capacity, and long range processing occur at different rates. Balance, posture, hearing, and speech can also be affected by declining brain function.

Physiologically, aging reduces blood supply to your brain...link to the full article to learn more.