Neurodegeneration and synaptic impairments mediated by chronic light-induced circadian rhythm and molecular signaling disruption: an insight beyond vision

Light not only provides visual information but also constitutes a powerful modulator of non-visual functions, including improvement of alertness and performance on several cognitive tasks. Over the last two decades, growing evidence has also shown that exposure to light from artificial sources is considered a pollutant for human health. The objective of this review is to update researchers in understanding the role of chronic light exposure and the mechanisms involved in neurological alteration. This review focuses on the role of lighting conditions in affecting non-visual consequences, especially the brain (learning and memory). The mechanistic approaches have been included and explained how chronic light induces neurological alterations in animal models. The review highlighted the impact and evidence of therapeutic alternatives evaluated and paucities in the management of neurodegenerative changes caused by chronic light exposure in preclinical studies. Beyond vision, the findings of the literature review indicated that chronic light exposure with different types, intensities, and exposure times leads to neurodegeneration and synaptic impairments via circadian rhythm and molecular signaling alterations. As for management, there are still many paucities. So, it becomes a major area for studies to be conducted as light pollution is increasing at its peak.