A female alcoholic presented with Wernicke's encephalopathy subsequent to administration of diazepam and glucose (without thiamine) for treatment of withdrawal seizures. Nystagmus and cerebellar ataxia quickly resolved when administered thiamine, although severe global amnesia consistent with Korsakoffs syndrome persisted. Magnetic resonance imaging (MRI) revealed infarction of the right temporal lobe with hippocampal atrophy, but no lesions of thalamus or atrophy of mammillary bodies. Positron emission tomography (PET) confirmed decreased cerebral metabolic rates for glucose (CMRglu) in the right temporal lobe corresponding to MRI findings, but also significant metabolic asymmetry of dorsal thalamus, i.e reduced CMRglu in left versus right. This patient is unique in that neuroradiological findings revealed intact mammillary bodies and suggest asymmetrical dysfunctions (structural right temporal and functional left diencephalic) to produce her profound amnesia.

One hundred and fifty unselected elderly community subjects were assessed by Mini Mental State Examination (MMSE), Abbreviated Mental Test (AMT) and Mental Status Questionnaire (MSQ). The effects on cognitive test scores of potential confounding (non-cognitive) variables were evaluated. Sensitivities and specificities were: MMSE 80% and 98%; AMT 77% and 90%; and MSQ 70% and 89%. The MMSE identified significantly fewer false positives than the AMT and MSQ. The major effect of intelligence on cognitive test scores has previously been underestimated. Age, social class, sensitivity of hearing and history of stroke were also significantly correlated with cognitive test scores. Years of full time education and depression only affected the longer MMSE and CAMCOG. The MMSE (cut-off 20/21) can be recommended for routine screening. However, as scores are affected by variables other than cognitive function, particularly intelligence, further assessment of identified cases may fail to reveal significant functional impairment.

The incidence of cavum septum pellucidum (CSP), which has been widely regarded as a developmental anomaly of little clinical importance in neuropathology, was examined in 113 patients with affective disorders (69 with bipolar disorder and 44 with major depression), 40 schizophrenic patients, and 92 control subjects by magnetic resonance imaging (MRI). Significantly higher incidence of Grade 3–4 CSP (moderate to large) compared with the controls was found only in the schizophrenics. When a broader interpretation of CSP, including indeterminant (Grade 1) and small (Grade 2) CSP was used, three additional patients with bipolar disorder were found to have Grade 1–2 CSP, and the total prevalence of Grade 1–4 CSP in the patients with bipolar disorder was significantly higher than that in the control subjects but slightly lower than that in the schizophrenic patients. CSP was not observed in any patient with major depression. There were no differences between the patients with and without CSP in age, sex, education, or the duration of illness. These findings are consistent with the hypothesis that neurodevelopmental abnormality may be present in schizophrenia, and such an abnormality may also be present in some patients with bipolar disorder.