one of four basic types of sleep disorders, differentiated from the other types in that it results from a mismatch between one’s internal circadian rhythm and one’s actual sleep schedule. The equivalent classification in DSM–IV–TR is circadian rhythm sleep disorder (or in DSM–5, circadian rhythm sleep–wake disorder). Rotating work-shift schedules and jet lag are two common causes of this disorder. Diagnosis can involve observation in a sleep laboratory, in which such criteria as nocturnal awakening, sleep time, sleep efficiency, breathing patterns, body temperature, minutes of REM sleep, and sleep latency are measured.
a phenomenon in which a subset of people with schizophrenia have particular difficulty visually integrating the parts of an object and seeing them as an ensemble. For example, if looking at a watch, they will perceive the hands, the dial, and the numbers as separate forms but will have difficulty processing the watch face as a whole. [coined by U.S. psychologist Steven M. Silverstein (1962– )]