Dim light in the evening causes coordinated realignment of circadian rhythms, sleep, and short-term memory

Tam SKE., Brown LA., Wilson TS., Tir S., Fisk AS., Pothecary CA., van der Vinne V., Foster RG., Vyazovskiy VV., Bannerman DM., Harrington ME., Peirson SN.

Significance In modern societies, people are regularly exposed to artificial light (e.g., light-emitting electronic devices). Dim light in the evening (DLE) imposes an artificial extension of the solar day, increasing our alertness before bedtime, delaying melatonin timing and sleep onset, and increasing sleepiness in the next morning. Using laboratory mice as a model organism, we show that 2 wk of 4-h, 20-lux DLE postpones rest–activity rhythms, delays molecular rhythms in the brain and body, and reverses the diurnal pattern of short-term memory performance. These results highlight the biological impact of DLE and emphasize the need to optimize our evening light exposure if we are to avoid shifting our biological clocks.

DOI

10.1073/pnas.2101591118

Type

Journal article

Journal

Proceedings of the National Academy of Sciences

Publisher

Proceedings of the National Academy of Sciences

Publication Date

28/09/2021

Volume

118

Permalink Original publication