Background Catatonia is a frequent, complex and severe identifiable syndrome of motor dysregulation. However, its pathophysiology is poorly understood. Methods We aimed to provide a systematic review of all brain imaging studies (both structural and functional) in catatonia. Results We identified 137 case reports and 18 group studies representing 186 individual patients with catatonia. Catatonia is often associated with brain imaging abnormalities (in more than 75% of cases). The majority of the case reports show diffuse lesions of white matter, in a wide range of brain regions. Most of the case reports of functional imaging usually show frontal, temporal, or basal ganglia hypoperfusion. These abnormalities appear to be alleviated after successful treatment of clinical symptoms. Structural brain magnetic resonance imaging studies are very scarce in the catatonia literature, mostly showing diffuse cerebral atrophy. Group studies assessing functional brain imaging after catatonic episodes show that emotional dysregulation is related to the GABAergic system, with hypoactivation of orbitofrontal cortex, hyperactivation of median prefrontal cortex, and dysconnectivity between frontal and motor areas. Conclusion In catatonia, brain imaging is abnormal in the majority of cases, and abnormalities more frequently diffuse than localised. Brain imaging studies published so far suffer from serious limitations and for now the different models presented in the literature do not explain most of the cases. There is an important need for further studies including a better clinical characterisation of patients with catatonia, functional imaging with concurrent catatonic symptoms and the use of novel brain imaging techniques.

Catatonia is a severe neuropsychiatric syndrome, usually treated by benzodiazepines and electroconvulsive therapy. However, therapeutic alternatives are limited, which is particularly critical in situations of treatment resistance or when electroconvulsive therapy is not available. Transcranial direct-current stimulation (tDCS) is a promising non-invasive neuromodulatory technique that has shown efficacy in other psychiatric conditions. We present the largest case series of tDCS use in catatonia, consisting of eight patients in whom tDCS targeting the left dorsolateral prefrontal cortex and temporoparietal junction was employed. We used a General Linear Mixed Model to isolate the effect of tDCS from other confounding factors such as time (spontaneous evolution) or co-prescriptions. The results indicate that tDCS, in addition to symptomatic pharmacotherapies such as lorazepam, seems to effectively reduce catatonic symptoms. These results corroborate a synthesis of five previous case reports of catatonia treated by tDCS in the literature. However, the specific efficacy of tDCS in catatonia remains to be demonstrated in a randomized controlled trial. The development of therapeutic alternatives in catatonia is of paramount importance.

ObjectiveCatatonia is a debilitating psychomotor disorder. Previous neuroimaging studies have used small samples with inconsistent results. We aimed to describe the structural neuroradiological abnormalities in clinical MRI brain scans of patients with catatonia and compare them to psychiatric inpatients without catatonia. We report the largest study of catatonia neuroimaging to date. MethodsIn this retrospective case-control study, neuroradiological reports of psychiatric inpatients who had undergone MRI brain scans for clinical reasons were examined. Abnormalities were classified by lateralisation, localisation and pathology. The primary analysis was prediction of catatonia by the presence of an abnormal MRI scan, adjusted for age, sex, Black ethnicity and psychiatric diagnosis. ResultsScan reports from 79 patients with catatonia and 711 other psychiatric inpatients were obtained. Mean age (SD) in the cases was 36.4 years (17.3) and 44.5 (19.9) in the comparison group. Radiological abnormalities were reported in 27 out of 79 cases (34.2%) and in 338 out of 711 in the comparison group (47.5%), OR 0.57 (0.35 to 0.93), aOR 1.11 (0.58 to 2.14). Among the cases, most abnormal scans had bilateral abnormalities (n=23, 29.1%), involved the forebrain (25, 31.6%) and involved atrophy (17, 21.5%). ConclusionsPatients with catatonia are commonly reported to have brain MRI abnormalities, which largely consist of diffuse cerebral atrophy rather than focal lesions, but there is no evidence that these abnormalities are more common than in other psychiatric inpatients undergoing neuroimaging, after adjustment for demographic variables. Study limitations include a heterogeneous control group and selection bias in requesting scans.