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pineal gland

a small, cone-shaped gland attached by a stalk to the posterior wall of the third ventricle of the brain; it is part of the epithalamus. In amphibians and reptiles, the gland appears to function as a part of the visual system. In mammals, it secretes the hormone melatonin and is an important component of the circadian system regulating biological rhythms. Because it is an unpaired organ located in the middle of the brain, René Descartes believed it was the seat of the rational soul and the connection between mind and body. Also called pineal body.

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Psychology term of the day

February 22nd 2025

sequela

sequela

n. (pl. sequelae) a residual effect of a disease, injury or mental condition, often (but not necessarily) in the form of persistent or permanent impairment. Examples include paralysis, which may be the sequela of poliomyelitis, and flashbacks, which may be the sequelae of traumatic stress.