Cognitive impairment in catatonia compared to other psychiatric disorders.

INTRODUCTION: Catatonia is a neuropsychiatric syndrome associated with cognitive impairments, yet the neurocognitive performance of catatonia relative to other psychiatric disorders is poorly understood. This study characterised neurocognitive profiles in patients with a history of catatonia compared to schizophrenia spectrum (SSD), bipolar disorder (BD), and major depressive disorder (MDD) across a comprehensive battery of neuropsychological tests. METHODS: Sixty-seven adults who underwent neuropsychological assessment were classified into catatonia (n = 10), SSD (n = 23), BD (n = 19), and MDD (n = 15) groups. Composite z-scores were generated across six domains: language, visuospatial skills, memory, attention, processing speed, and executive functioning. RESULTS: Global neurocognitive functioning was similar, and approximated population norms, in BD and MDD, but significantly lower in catatonia (z = -1.63) and SSD (z = -1.14) groups. Significant differences emerged in overall neurocognitive scores (ηp2 = .47) and memory, attention, processing speed, executive functioning (ηp² = 0.30-0.41), but not language. Post hoc tests showed MDD and BD outperformed SSD and catatonia groups, with no differences within these pairs. Neurobehavioural examinations distinguished catatonia from SSD by increased affective blunting, withdrawal, psychomotor slowing, and slow mentation. CONCLUSIONS: Catatonia is associated with substantial neurocognitive impairment, most similar to SSD, but with distinct neurobehavioural features. Routine screening and targeted neurocognitive assessment may enhance diagnosis and understanding of catatonia.