Rhythm and mood: relationships between the circadian clock and mood-related behavior.

Mood regulation: The paper discusses how the circadian clock mechanisms affect the regulation of different mood pathways, suggesting that defects in the circadian clock mechanism and system may contribute to mood disorders.

Depression: The paper discusses how mood disorders, including depression, are often accompanied by abnormalities in the organization of the circadian system.

Cognitive function and memory: The paper discusses how the circadian clock mechanisms are implicated in the modulation of biological phenomena regulating affective behaviors, which could potentially impact cognitive function and memory.

Shift work: The paper discusses how shift work, which can cause a misalignment between the circadian clock and the environment, may be a risk factor for mood disorders.

Jet lag: The paper discusses how jet lag, which causes a mismatch between the timing of the endogenous circadian clock and the external environment, may exacerbate existing mood disorders.

Phototherapy: The paper discusses how modification of the circadian system using chronotherapy, a type of phototherapy, appears to be an effective treatment for mood disorders.