occurring during sleep or sleep-wake transitions. Compare with DYSSOMNIAS .
perseveration Persistence at tasks or in particular way of doing things long after the be-
havior has ceased to be functional or effe ctive; continuance of the same behavior de-
spite repeated failures or clear reasons fo r stopping. Perseveration is a facet of the
broad personality trait domain N EGATIVE  AFFECTIVITY .
personality Enduring patterns of perceiving, relating to, and thinking about the envi-
ronment and oneself. P ERSONALITY  TRAITS  are prominent aspects of personality that are
exhibited in relatively consist ent ways across time and across situations. Personality
traits influence self and interpersonal func tioning. Depending on their severity, im-
pairments in personality functioning and personality trait expression may reflect the
presence of a personality disorder.
personality disord er—trait specified In Section III “Alternative DSM-5 Model for Per-
sonality Disorders,” a proposed diagnostic category for use when a personality disor-
der is considered present but the criteria for a specific disorder ar e not met. Personality
disorder—trait specified (PD-TS) is defined by significant impairment in personality
functioning, as measured by the Level of Personality Functioning Scale and one or
more pathological PERSONALITY  TRAIT  DOMAINS  or PERSONALITY  TRAIT  FACETS . PD-TS is
proposed in DSM-5 Section III for further st udy as a possible future replacement for
other specified personality disorder and unspecified personality disorder.
personality functioning Cognitive models of self and othe rs that shape patterns of emo-
tional and affiliative engagement.
personality trait A tendency to behave, feel, perceive , and think in relatively consistent
ways across time and across situations in which the trait may be manifest.