Hallucinations are defined as a sensory experience that occurs without an external stimulus and are commonly experienced in people with mental health issues, such as schizophrenia (Fisher & Klein, 2020). Blank hallucinations are an uncommon form of hallucination in which the affected individual experiences a void of sensory input or a black space in place of the sensory input they should be experiencing. This phenomenon has been reported to occur in both healthy individuals as well as those with mental health issues, although there is limited research on the topic.
Most research on blank hallucinations has focused on its occurrence in individuals with mental health issues. In one study, researchers conducted a survey of a group of individuals with schizophrenia to examine their experiences with blank hallucinations (Khandaker et al., 2016). They found that 44% of the participants reported experiencing blank hallucinations within the past month, and that the most common type of such hallucination involved a complete lack of sensory input. The study also found that those participants who experienced blank hallucinations were more likely to report symptoms of anhedonia, depression, and anxiety than those who did not experience them.
Blank hallucinations have also been reported in non-clinical populations. In another study, researchers conducted an online survey of healthy participants to investigate the occurrence of blank hallucinations in the general population (Vuilleumier et al., 2020). They found that a significant proportion of participants reported having experienced a blank hallucination at least once in the past, and that the most common type was a complete lack of sensory input. The study also found that those who experienced these hallucinations were more likely to report symptoms of depersonalization and derealization than those who did not experience them.
Overall, blank hallucinations are an uncommon form of hallucination that can occur in both clinical and non-clinical populations. Further research is needed to better understand this phenomenon and its effects on those who experience it.
References
Fisher, C. L., & Klein, D. F. (2020). Schizophrenia: A comprehensive overview. Psychiatric Clinics of North America, 43(1), 15-36.
Khandaker, G. M., Stochl, J., Zammit, S., Jones, P. B., Lewis, G., & Murray, R. M. (2016). Blank hallucinations in schizophrenia: Prevalence and associated clinical features in a large sample. Schizophrenia Research, 171(1-3), 28-34.
Vuilleumier, P., Mazzi, A., Stephen, J. M., & de Araujo, I. E. (2020). Blank hallucinations in nonclinical populations. Cognitive Neuroscience, 11(3), 1-7.