<prompt> Which of the following sites is responsible for the amnestic defect in Wernickes Korsakoff syndrome:Mamillary bodyThalamusPeriventricular Grey matterHippocampus  <response>: Answer is B Thalamus: The Amnestic effect in Wernickes Korsakoff Syndrome is related to lesions in the dorso-medial nuclei of the thalamus. Lesions in the dorsomedial nucleus of the thalamus seem to be the best correlate of the memory disturbance and confabulation - Robbins 