In an effort to aid the clinician in the differential diagnosis of catatonic states, we assessed the nature of electroencephalography (EEG) findings in both medical and psychiatric forms of catatonia. An exhaustive review of the literature on catatonia due to a general medical condition (CDGMC) was performed in addition to a prospective review of catatonic patients at The Ohio State University Neuwpsychiatric Facility.
A total of 105 patients had documented, specific clinical and EEG information, with neurologic conditions accounting for 82.8% of case reports. Results from the case series of 31 episodes of catatonia indicate that there is an increased likelihood of diffuse slowing in patients with CDGMC versus psychiatric catatonia. Given the observed rate of abnormalities, EEG is an important but underutilized tool in the differential diagnosis of catatonic disorders.