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Cited by 408

The DOI matches its Crossref record; 34 of the 34 references it cites were found in a registry or an index.

Circadian rhythm abnormalities in totally blind people: incidence and clinical significance

Sack, R. L.·1992·Journal of Clinical Endocrinology & Metabolism

Abstract

When people are completely isolated from environmental time cues, their circadian rhythms free run with a nearly 24-h cycle, generated by an internal body clock. Free-running temperature, cortisol, and melatonin rhythms have also been described in totally blind people, even though they were living in normal society and had access to abundant time cues; thus an intact visual system may be essential for synchronization of the circadian system. However, because of the small numbers of subjects studied, the incidence and clinical significance of circadian rhythm abnormalities among the blind has remained uncertain. In this study, plasma melatonin (n = 20), cortisol (n = 4), and sleep propensity (n = 1) were measured in serial samples taken from totally blind subjects for 24 h. Most totally blind subjects had circadian rhythm abnormalities. In about half of the subjects, the rhythms were free-running. Some blind subjects suffered recurrent insomnia and daytime sleepiness that were maximal when the internal rhythms were out of phase with the preferred sleep times. The high incidence of abnormal circadian rhythms in blind people underscores the importance of the light-dark cycle as an important environmental synchronizer for the human circadian system.

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Metadata

Authors
Sack, R. L.
Venue
Journal of Clinical Endocrinology & Metabolism
Published
1992-07-01
Volume
75
Issue
1
Pages
127-134
ISSN
0021-972X (ISSN-L)
OpenAlex
W2082442275
Cited by
408
References
34
FWCI
7.40
Type
journal article
Language
en
Open access
closed

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CoChat. (2026). Citation check: Circadian rhythm abnormalities in totally blind people: incidence and clinical significance. https://app.cochat.ai/papers/10.1210/jc.75.1.127
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Sack, R. L. (1992). Circadian rhythm abnormalities in totally blind people: incidence and clinical significance. Journal of Clinical Endocrinology & Metabolism. https://doi.org/10.1210/jc.75.1.127

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

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