can also occur, whereby voices or sounds ar e muted or heightened. In addition, Criterion
C requires the presence of clinically signific ant distress or impairment in social, occupa-
tional, or other important areas of functionin g, and Criteria D and E describe exclusionary
diagnoses. 
Associated Features Supporting Diagnosis
Individuals with depersonalization/derealizat ion disorder may have difficulty describ-
ing their symptoms and may think they are “crazy” or “going crazy”. Another common
experience is the fear of irreversible brai n damage. A commonly associated symptom is a
subjectively altered sense of time (i.e., too fast  or too slow), as well as a subjective difficulty
in vividly recalling past memories and owning  them as personal and emotional. Vague so-
matic symptoms, such as head fullness, ting ling, or lightheadedne ss, are not uncommon.
Individuals may suffer extreme rumination or  obsessional preoccupation (e.g., constantly
obsessing about whether they really exist, or checking their perc eptions to determine
whether they appear real). Varying degrees of  anxiety and depression are also common as-
sociated features. Individuals with the disord er have been found to have physiological
hyporeactivity to emotional stimuli. Neural substrates of interest include the hypotha-
lamic-pituitary-adrenocortical ax is, inferior parietal lobule, and prefrontal cortical-limbic
circuits.
Prevalence
Transient depersonalization/derealization sy mptoms lasting hours to days are common
in the general population. The 12-month prev alence of depersonalization/derealization
disorder is thought to be markedly less than  for transient symptoms, although precise es-