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Ability to Identify Odors Inferior in Schizophrenia Patients

Key clinical point: Compared with healthy controls, individuals with schizophrenia and those at risk for psychosis have a significantly shallower olfactory sulcus and showed impairment in odor identification.

Major finding: On average, the olfactory sulcus in at-risk individuals and schizophrenia patients, was significantly bilaterally shallower than in controls (P less than 0.001).

Study details: The data come from 38 adults with an at-risk mental state, 62 adults with schizophrenia, and 61 healthy controls.

Disclosures: The study was supported by several entities, including the Japan Agency for Medical Research and Development. The researchers had no financial conflicts to disclose.


Takahashi T et al. Heliyon. 2019. doi: 10.1016/j.heliyon.2019.e02642.


Prior research suggests that people with schizophrenia may have abnormalities in the olfactory system, including a reduced ability to sense and differentiate smells. It seems likely that olfactory deficits occur in tandem with some of the other impairments seen among individuals with schizophrenia, including well-established abnormalities in the ability to process social and affective information. This study used neuroimaging to assess structural brain differences in patients with schizophrenia and those at high risk for psychosis. Morphological difference between patients and high risk individuals vs. controls support the neurodevelopment basis of schizophrenia and suggest that olfactory sulcus morphology represents a stable trait marker of psychosis.—Martha Sajatovic, MD, Professor of Psychiatry and of Neurology; Willard Brown Chair in Neurological Outcomes Research; Director, Neurological and Behavioral Outcomes Center, University Hospitals Cleveland Medical Center; Case Western Reserve University School of Medicine.