Sexual hallucinations: Phenomenological characteristics and relation with trauma and the incubus phenomenon

Sexual hallucinations are hardly researched phenomena. Clinical practice
indicates that they can be extremely burdening, driving patients to unusual and
sometimes desperate behaviour - occasionally entailing suicide. A recent study
by Blom and Mangoenkarso (2018) among clinical patients diagnosed with
schizophrenia yielded a one-year prevalence rate of 0.017 for sexual
hallucinations. Moreover, it yielded a strong correlation with childhood
trauma, with an OR of 8.7. Since childhood trauma is also oft-reported in the
context of borderline personality disorder, we expect that sexual
hallucinations can be found in this group, too, and that they may well be
underreported in clinical practice. There is no prior research in this area, so
similar to the schizophrenia group, we would like to establish the prevalence
rate of sexual hallucinations in the population of patients diagnosed with
borderline personality disorder, as well as their relation with childhood
trauma. Because sexual hallucinations can also be experienced in the context of
sleep paralysis (i.e., incubus phenomenon), we would like to investigate this
possible connection, too.

To establish the point prevalence rate as well as the lifetime prevalence rate
of sexual hallucinations in patients diagnosed with a bordeline personality
disorder, and to establish the relation of these hallucinations with childhood
trauma as well as with sleep paralysis (i.e., incubus phenomenon).

Test persons (N=200) will be recruited at outpatient clinics of PsyQ, Parnassia
Psychiatric Institute. After explanation of the study and after test persons
have given their informed consent, the following questionnaires will be
administered:
- Vragenlijst Seksuele Hallucinaties en Wanen (VSHW)
- Jeugd Trauma Vragenlijst - Lange Versie (JTV-LV)
- Insomnia Severity Index (ISI)
- Waterloo Unusual Sleep Experiences Scale (WUSES) - Dutch version
The results will be analysed with the aid of SPSS version 23.0.

The investment in time will be approximately 90 minutes per test person. There
is a certain risk that participants will experience several questions as
intrusive in nature, although in our experience most of them are relieved when
they are able to talk about this theme. Moreover, the results of the individual
interviews - if the patient allows them to be shared with their treating
physician - can help to improve their diagnosis and treatment.