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gnothi se auton

know thyself (Greek). These words, which were inscribed over the portico of the temple of Apollo at Delphi in ancient Greece, have been ascribed to various sources. The pursuit of self-knowledge, or knowledge of the psyche, became a key element in the philosophical project of Socrates. In a sense, this project is the fundamental undertaking of psychology.

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Psychology term of the day

May 26th 2024

metachromatic leukodystrophy

metachromatic leukodystrophy

an autosomal recessive disorder (see recessive allele) characterized by deficiency or absence of the enzyme arylsulfatase A, which results in loss of myelin in the nervous system and accumulation of cerebroside sulfate (a type of myelin lipid) within the white matter of the central nervous system. Loss of motor function and deterioration in mental ability most commonly develop after the 1st year of life (late infantile form), but symptoms may also appear between 3 and 10 years of age (juvenile form) or around age 30 (adult form).