Post-bereavement hallucinatory experiences: A critical overview of population and clinical studies

Removal of the "bereavement exclusion" criterion for major depression and proposed research criteria for persistent complex bereavement disorder in DSM-V pose new compelling issues regarding the adequacy of current nosographical boundaries. Post-bereavement hallucinatory experiences (PBHE) are abnormal sensory experiences that are frequently reported by bereaved individuals without a history of mental disorder. Given current uncertainty over the continuum of psychotic experiences in the general population, whether or not they should be considered pathological remains unclear.

In order to systemize available knowledge, we reviewed the literature describing general population and clinical studies on PBHEs. Given the relatively low number of articles, all peer-reviewed, published studies in English were included. No study characteristics or publication date restrictions were imposed.

Overall, evidence suggests a strikingly high prevalence of PBHEs - ranging from 30% to 60% - among widowed subjects, giving consistence and legitimacy to these phenomena.

Whereas general population studies had adequate sample size numbers, all studies in the bereaved population had a very small number of subjects. No consensus for method of evaluation exists in the literature, with some studies using a free interview method and others using semi-structured interviews.

The available literature appears to support an elevated frequency of PBHEs in bereaved individuals, but further research is needed to increase the reliability of these findings and refine the boundaries between physiological and pathological experiences.