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group boundary

the implicit and explicit standards that set limits on aspects of the group, including who can be members, the expected duties of members, and the types of actions that the group will permit members to perform.

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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).