Dim lighting can have an impact on memory settling, mainly through its influence on sleep quality and brain function. When the environment is dimly lit, especially in the evening, it helps the body produce melatonin, a hormone that regulates sleep. Better sleep supports memory consolidation, which is the process where the brain stabilizes and stores memories after learning. In contrast, bright or blue light exposure at night can disrupt this process by delaying melatonin production and disturbing the circadian rhythm, leading to poorer memory retention[1][5][6].
Research shows that dimming lights before bedtime creates a calm atmosphere that signals the brain to prepare for rest. This helps reduce cortisol levels (a stress hormone) and stabilizes blood pressure, which together support heart health and brain repair during sleep. Since memory consolidation largely happens during sleep, a dimly lit environment indirectly improves memory by promoting deeper, more restorative sleep cycles[1][6].
On the other hand, studies indicate that dim lighting during active memory tasks may not always be beneficial. Some findings suggest that dim environments can lead to declines in spatial and verbal memory performance, possibly because lower light reduces alertness and attention, which are crucial for encoding new information[3]. Bright light exposure during the day or in the morning, conversely, can enhance alertness and cognitive performance by activating brain arousal pathways[2].
In practical terms, using dim, warm-toned lighting in the evening and avoiding screens or bright lights before sleep can help memory settling by improving sleep quality. During the day, exposure to natural or bright light supports attention and memory encoding. Thus, the timing and context of dim lighting are important: it benefits memory indirectly by fostering good sleep but may impair memory tasks if used during active learning or recall.
Sources
https://timesofindia.indiatimes.com/life-style/health-fitness/health-news/dim-your-lights-at-night-and-save-your-heart-scientists-reveal-why/articleshow/124849546.cms
https://www.psychiatrypodcast.com/psychiatry-psychotherapy-podcast/episode-251-combatting-the-negative-effects-of-sleep-deprivation
https://jordansheridan.com/exploring-the-relationship-between-light-and-memory/
https://www.calm.com/blog/types-of-memory
https://masscarelink.org/brain-health-basics-everyday-habits-to-support-memory/
