Researchers have found that aging results in significant reduction to light sensitivity in a part of the brain which controls circadian rhythms called the suprachiasmatic nucleus.This discovery may help to target treatments which aim to improve behavioral and physiological circadian clock resetting in older individuals.
Researchers explored alterations in a pathway in the part of the brain controlling circadian rhythms and found a glutamate receptor used to transmit light information becomes less effective in resetting the circadian clock as part of the aging process. Structural change in the glutamate receptor was responsible for decline in observed light response. NMDA receptor subunits exhibited marked decrease in presence among older mammals which is an indicator of age associated structural configuration change.
Researchers concluded that the aging SCN suffers from a structural reorganization of light receiving components that impair function in maintaining and setting a stable circadian rhythm.