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bipolar disorder

any of a group of mood disorders in which symptoms of mania and depression alternate. In DSM–IV–TR and DSM–5, the group includes primarily the following subtypes: bipolar I disorder, in which the individual fluctuates between episodes of mania or hypomania and major depressive episodes or experiences a mix of these: bipolar II disorder, in which the individual fluctuates between major depressive and hypomanic episodes; and cyclothymic disorder. The former official name for bipolar disorders, manic-depressive illness, is still in frequent use.

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Psychology term of the day

February 21st 2025

Hoover’s sign

Hoover’s sign

a diagnostic test for neurological (as distinct from psychological) hemiplegia in which the individual in a reclining position attempts to raise the paralyzed leg: An individual with true hemiplegia reflexively presses down the heel of the healthy leg during the test. The absence of the downward movement is a positive Hoover’s sign and suggests psychogenic paresis or malingering. [Charles Franklin Hoover (1865–1927), U.S. physician]