The neural correlates of impaired consciousness in coma and unresponsive states.

Over the last few years, functional neuroimaging studies have provided new insights into cerebral activity in subjects with severe brain damage leading to coma and other clinical states characterized by unresponsiveness. The present paper introduces the clinical picture of patients with impaired consciousness, and reviews the nosological criteria and functional neuroanatomical basis for brain death, coma, vegetative state, minimally conscious state, and the locked-in syndrome. Converging evidence suggests that disrupted activity in higher-order association areas, especially prefrontal and posteromedial parietal regions, plays a pivotal role within the neural correlates of impaired consciousness in the unresponsive patient.

Depression in women with epilepsy: clinical and neurobiological aspects.

Patients affected by epilepsy show a considerably higher incidence of depression compared with the general population. Since women are twice as likely as men to suffer from depression, female gender could be considered a major risk factor for developing this condition. Converging lines of evidence suggest that sex hormones, which are known to contribute to remodelling the hippocampus, play a pivotal role in both epilepsy and depression. In women, the role of sex hormone levels may be more important because of their physiological cyclic fluctuations. Oestrogens, more than other ovarian hormones, show an effect similar to antidepressant drugs by stimulating hippocampal synaptogenesis, thus exerting a protective role against seizures as well. This paper reviews the current knowledge on the neurobiological basis of depression in women with epilepsy. The emerging picture informs therapeutic strategies to improve the clinical management of this common comorbidity.