Biology lettersNov 22, 2023

Artificial Light at Night Before Birth Reduces Learning and Changes Behavior Links in Fish

Circadian Biology Weekly Brief ↗PubMed ↗DOI ↗

Updated Mar 28, 2026

Abstract

Zebrafish larvae exposed to artificial light at night (ALAN) learned significantly slower than control larvae.

Larvae exposed to ALAN required more events to acquire ecologically relevant information compared to control larvae.
Control zebrafish exhibited a significant relationship between learning performance and two behavioral traits, which was disrupted by ALAN exposure.
ALAN exposure resulted in an average increase in larval activity.
Cognitive abilities of zebrafish and individual differences may be negatively impacted by light pollution even after short embryonic exposure.

Simplified

The natural light cycle has profound effects on animals' cognitive systems. Its alteration owing to human activities, such as artificial light at night (ALAN), affects the biodiversity of mammalian and avian species by impairing their cognitive functions. The impact of ALAN on cognition, however, has not been investigated in aquatic species, in spite of the common occurrence of this pollution along water bodies. We exposed eggs of a teleost fish (the zebrafish) to ALAN and, upon hatching, we measured larvae' cognitive abilities with a habituation learning paradigm. Both control and ALAN-exposed larvae showed habituation learning, but the latter learned significantly slower, suggesting that under ALAN conditions, fish require many more events to acquire ecologically relevant information. We also found that individuals' learning performance significantly covaried with two behavioural traits in the control zebrafish, but ALAN disrupted one of these relationships. Additionally, ALAN resulted in an average increase in larval activity. Our results showed that both fish's cognitive abilities and related individual differences are negatively impacted by light pollution, even after a short exposure in the embryonic stage. Danio rerio

Full Text

Full text is available at the source.

View Full Text ↗

Funding

Competing interests

We declare we have no competing interests.

PubMed

Artificial Light at Night Before Birth Reduces Learning and Changes Behavior Links in Fish

Abstract

Full Text

Funding

Competing interests

You found one interesting study. We’ll send the next 7.

What Lands in Your Inbox Each Week:

Recent issues from the circadian biology brief

Abstract

Full Text

Funding

Competing interests

Related papers

You found one interesting study. We’ll send the next 7.

What Lands in Your Inbox Each Week:

Recent issues from the circadian biology brief