Thrombosis of the deep cerebral venous system is usually fatal, and patients are frequently stuporous or comatose at presentation. This report describes serial radiological and neuropsychological observations in an 18-year-old woman who remained alert and survived this disorder. In association with diencephalic edema seen on computed tomographic scan, she demonstrated disorientation, abulia, attentional deficits, memory loss, and dyscalculia and had impaired IQ scores: the performance scores were worse than the verbal scores. Significant aphasia or sensory loss was absent. She recovered full intellectual capacity in the course of follow-up examinations, and the diencephalic edema seen on the computed tomographic scan resolved despite persistent thrombosis of the straight sinus demonstrable on follow-up digital angiography.