The function of clock input and output pathways in zebrafish

Cognitive function and memory: The paper explores the role of the per2 gene in the circadian clock of zebrafish, which is relevant to cognitive function and memory as circadian rhythms are known to influence these aspects.

Hormone regulation: The per2 gene, as part of the circadian clock, plays a role in hormone regulation, as suggested by the paper's exploration of its impact on the rhythmic expression of core clock genes.

Sleep and insomnia: The paper's investigation into the per2 gene's role in the circadian clock and its impact on rhythmic locomotor activity is relevant to sleep and insomnia, as disruptions in these areas can contribute to sleep disorders.

Aging: The paper's exploration of the per2 gene's role in the circadian regulation of the cell cycle could have implications for aging, as disruptions in cell cycle regulation are associated with aging processes.

Education and learning: The paper's findings on the per2 gene's role in the circadian clock and its impact on cognitive function and memory could have implications for education and learning, as these cognitive functions are crucial for learning processes.