Ocular light plays a key role in human physiology by transmitting time of day information. The production of the pineal gland hormone melatonin is under the control of the light-dark cycle. Its profile of secretion defines biological night and it has been called the 'darkness hormone'. Light mediates a number of non-visual responses, such as phase shifting the internal circadian clock, increasing alertness, heart rate and pupil constriction. Both exogenous melatonin and light, if appropriately timed, can phase shift the human circadian system. These 'chronobiotic' effects of light and melatonin have been used successfully to alleviate and correct circadian rhythm disorders, such as those experienced following travel across time zones, in night shift work and in circadian sleep disorders. The effectiveness of melatonin and light are currently being optimized in terms of time of administration, light intensity, duration and wavelength, and melatonin dose and formulation. The aim of this review is not to replicate information that has been reported in a number of reviews of the human circadian timing system and the role of melatonin and light, but rather to extract findings relevant to the field of clinical biochemistry.
This research output has an Altmetric Attention Score of 43. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 13 May 2025.
All research outputs
#1,093,893
of 28,832,041 outputs
Outputs from Annals of Clinical Biochemistry
#9
of 1,435 outputs
Outputs of similar age
#1,871
of 97,357 outputs
Outputs of similar age from Annals of Clinical Biochemistry
#1
of 6 outputs
Altmetric has tracked 28,832,041 research outputs across all sources so far. Compared to these this one has done particularly well and is in the 96th percentile: it's in the top 5% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 1,435 research outputs from this source. They receive a mean Attention Score of 4.0. This one has done particularly well, scoring higher than 99% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 97,357 tracked outputs that were published within six weeks on either side of this one in any source. This one has done particularly well, scoring higher than 98% of its contemporaries.
We're also able to compare this research output to 6 others from the same source and published within six weeks on either side of this one. This one has scored higher than all of them
