NIOSH Training for Nurses on Shift Work and Long Work Hours
Circadian Rhythms (Continued)
Figure 2.4. Light enters the eyes, stimulating a signal in the back of the retina and down a nerve tract to the circadian pacemaker in the brain. Adapted from National Institutes of Health and BSCS. 2003. Sleep, sleep disorders, and biological rhythms. NIH publication no. 04-4989.
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