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

January 19th 2025

holism

n. any approach or theory holding that a system or organism is a coherent, unified whole that cannot be fully explained in terms of individual parts or characteristics. The system or organism may have properties as a complete entity or phenomenon in addition to those of its parts. Thus, an analysis or understanding of the parts does not provide an understanding of the whole. —holistic adj.