Are Hallucinations Therapeutic?

Earlier this month, Australia became the first nation to grant approval for psychedelics for the treatment of mental illness, including post-traumatic stress disorder and major depression. Although psychedelics have been authorized for use, full implementation by psychiatric professionals is expected to take longer due to additional safeguards regarding procurement and importation of these agents. Nevertheless, Australia’s actions represent a pioneering move towards a paradigm shift in clinical psychiatry.

The Benefits of Psilocybin and MDMA for Mental Illness Grow

Mounting research supports the efficacy of psychedelics in the treatment of mental illness. A 2022 publication in the New England Journal of Medicine demonstrated that a single dose of psilocybin at 25mg effectively ameliorated depressive scores among a cohort of 79 participants. Research also indicates that MDMA-assisted psychotherapy is more effective among PTSD patients than usual care or psychotherapy without such augmentation. There remains ongoing debate over whether the hallucinatory experience associated with these agents is instrumental—or even essential—for the demonstration and sustainability of their therapeutic effects. With few exceptions, psychiatry has historically maintained the position that hallucinations represent a need for treatment. Investigations hope to determine if therapeutic benefit is possible without accompanying hallucinations. However, this search may be misguided.

Hallucinations Without Mental Illness

Hallucinations commonly occur in the absence of a mental illness. Dreamlike states may produce hallucinations at sleep onset and offset, referred to as hypnagogic and hypnopompic hallucinations. These experiences are often visual in nature and widely accepted as benign events that do not require treatment, although they may infrequently co-occur with certain sleep disorders such as narcolepsy.

Grief is a mental state experienced by many individuals after a significant loss and is often accompanied by hallucinations. In a 2021 survey of 310 older Danish adults, 42 percent of participants experienced bereavement hallucinations six to ten months following the death of their spouse. Although hallucinations occurred in multiple sensory domains, seeing and hearing a deceased loved one were especially common, and these events were often perceived as comforting.

Should Hallucinations be Induced Therapeutically?

One aspect of the debate that limits implementation of psychedelics for psychiatric indications is the potential induction of a psychotic state. The human experience of hallucinations that co-occur with grief and sleep arise without clinical intervention. Some may feel that the prospect of a mental health provider inducing a hallucination willfully through use of psilocybin or MDMA is counterintuitive given psychiatry’s historical canon that hallucinations indicate a mental illness. However, the social valence of hallucinations as pathological or normative is deeply embedded in a cultural framework. Wallace described, in a classic 1959 paper, that although Western societies often consider hallucinations as a symptom of mental illness, many non-Western societies do not, and in fact, often perceive hallucinations as a healing element in their explanatory models of medical ailments.

The purposeful induction of altered states of consciousness for therapeutic value in psychiatry is best represented by hypnosis. Despite a multitude of uses, clinical hypnosis is sometimes received as a “fringe” treatment without substantial benefit.

To be sure, not all hallucinations are beneficial, and a reasoned and thorough clinical assessment is warranted in any patient with such experiences. I am an emergency psychiatrist in a large metropolitan hospital tasked with assessing safety among patients in states of crisis. Hallucinations are a frequent finding in my patient population. Those that incur risk of self-harm, such as voices directing an individual to end their own life, are a definite focus of treatment and should not be dismissed. Additionally, research and clinical equipoise for psychedelics must govern the approach of the field; clinical enthusiasm must be tempered by rigorous evaluation of these agents in well-designed studies.

Cultural change is rarely seismic or rapid. Psychedelics present a useful pivot point in psychiatry's cultural understanding of hallucinations and a move towards recognition that these experiences are not routinely pathological. Adopting this lens can propel progress not just in the clinical care of disabling mental illnesses, but also in eliminating the stigma that patients experience.