The obsessive-compulsive spectrum may be too broad
STUDY: Kobayashi T, Psychiatry and Clinical Neurosciences Reports 2026
STUDY TYPE: Theoretical psychopathology review
FUNDING: Independent
Background
The DSM-5 groups obsessive-compulsive disorder together with conditions like trichotillomania, hoarding disorder, excoriation disorder, and body dysmorphic disorder under one obsessive-compulsive spectrum, on the theory that they share underlying brain reward and impulse-control mechanisms.
But classical European psychopathology, Kraepelin, Jaspers, Schneider, defined true obsessionality more narrowly, as a specific cognitive structure rather than just repetitive thoughts or behaviors. This paper argues the spectrum’s expansion has blurred a clinically useful distinction.
Summary
Classical obsessionality requires five features together:
- Repetitiveness
- A compelling force
- Accompanying anxiety
- Awareness that the thought is irrational
- An ego-dystonic experience the patient still recognizes as their own
Many conditions now grouped under the obsessive-compulsive umbrella, especially trichotillomania and hoarding, lack this structure. They tend to be ego-syntonic, less anxiety-driven, and often accompanied by poor insight, features that resemble impulsivity, addiction, or neurologically driven stereotypy more than classical obsessions.
The author proposes a provisional category, “middle-voiced repetitive phenomena,” for behaviors that are neither fully willed nor fully involuntary, while preserving a narrower, more clinically precise definition of true obsessionality.
Practice Implications
- There is pharmacologic sense here as well, as non-classic obsessions like trichotillomania, hoarding, and anorexia do not respond to SSRIs.
—Chris Aiken, MD
Director, Psych Partners
Editor in Chief, Carlat Psychiatry Report
