Search

Reports on a patient who developed a dysexecutive syndrome and a moderate learning deficit following a head trauma. Definition of anosognosia; Main groups of theories that attempted to account for anosognosia; Evaluation of the patient's anosognosia.

Background: Huntington's disease is a neurodegenerative disease of genetic origin that mainly affects the striatum. It has severe motor and cognitive consequences and, up to now, no treatment. Motor and cognitive functions can be restored in experimental animal models by means of intrastriatal transplantation of fetal striatal neuroblasts. We explored whether grafts of human fetal striatal tissue could survive and have detectable effects in five patients with mild to moderate Huntington's disease., Methods: After 2 years of preoperative assessment, patients were grafted with human fetal neuroblasts into the right striatum then, after a year, the left striatum. Final results were assessed 1 year later on the basis of neurological, neuropsychological, neurophysiological, and psychiatric tests. The results obtained were compared with those of a cohort of 22 untreated patients at similar stages of the disease who were followed up in parallel. Repeated magnetic resonance imaging (MRI) and positron emission tomography (PET) scanning with fluorine-18-labelled fluorodeoxyglucose was also done to assess metabolic activity., Findings: The final PET-scan assessment showed increased metabolic activity in various subnuclei of the striatum in three of five patients, contrasting with the progressive decline recorded in the two other patients in the series, as seen in patients with untreated Huntington's disease. Small areas of even higher metabolic activity, coregistering with spherical hyposignals on MRI were also present in the same three patients, suggesting that grafts were functional. Accordingly, motor and cognitive functions were improved or maintained within the normal range, and functional benefits were seen in daily-life activities in these three patients, but not in the other two., Interpretation: Fetal neural allografts could be associated with functional, motor, and cognitive improvements in patients with Huntington's disease.

In this study we report a patient, MG, who following rupture of left posterior communicating artery exhibited an amnesic-confabulatory syndrome. Neuropsychological examination showed severe impairment on episodic memory tasks, which were marred by florid but plausible and semantically appropriate confabulation. Performance on tasks involving various kinds of semantic knowledge was normal or only mildly impaired. Performance on tasks traditionally considered sensitive to frontal dysfunction was severely impaired with the exception of Cognitive Estimates where MG's performance was completely normal. There was no evidence of structural (CT scan) or metabolic (SPECT) damage to the frontal lobe. It is argued that tasks traditionally considered sensitive to frontal dysfunction are not specifically implemented by cognitive resources based on frontal structures. MG's confabulation is discussed in terms of a possible disruption of cognitive functions involved in the control of the subjective experience of feeling of remembering.