University:
Western Sydney University
Course:
MEDI 2003 | Clinical Sciences 2
Academic year:

2024
Views:

85

Pages:

3
Author:

Mariam A.

Diencephalic amnesia      Wernicke-Korsakoff’s syndrome: o Patients develop amnesia as a result of alcohol abuse and thiamine deficiency. o Other causes include malabsorption, renal insufficiency, and dietary restrictions. o In Wernicke phase, patients demonstrate oculomotor disturbance, ataxia and confusion; gives way to Kosakoffian phase. o Problem: global amnesia but tend to confabulate, have poor insight, and have a more variable retrograde amnesia. Thalamotomy: o Involves ablation of one or more thalamic nuclei for relief of Parkinson’s disease. o Usually, the dorsomedial thalamic nuclei are targeted resulting in amnesia. Penetrating head injury: o North American young service man had a head injury; fencing foil entered right nostril. o Neuropathology: left thalamus, left mamillio-thalamic tract, mammillary bodies, hypothalamus, and the anterior temporal lobe. o Problem: marked amnesia. Tumours: o Notably third ventricle. o Pressure on surrounding tissue including thalamus. o Amnesia improves often with removal of tumour. Thalamic infarction/haemorrhage: o Accounts for about 10% of all intracranial haemorrhages. o Appears dependent on infarction occurring in the paramedian territory, one of the arterial supplies within the thalamus. o Problem: persistent amnesia. Material specific memory disorders  Damage is usually unilateral and selectively affects either visual or verbal memory.  Temporal lobectomy for intractable complex partial seizures; anterior 5cm of temporal lobe. o Left TL: verbal memory deficit (word lists, prose passage). o Right TL: non-vernal learning deficit (maze learning, recall of designs, faces).  Strokes: o Posterior cerebral artery (hippocampus and thalamic nuclei). o Middle cerebral artery: damage to right temporoparietal areas lead to topographical disorientation. Frontal amnesia  Memory disorder secondary to damage to the frontal cortex.    o Cerebrovascular tumours. o Head injury. o Surgical intervention for frontal lobe seizures. o Rupture and repair of anterior communicating artery. Register new information, but there is: o Inability to organise material to commit it to memory. o Information associated with the wrong context or confabulations. o Retrieval difficulties evidences on free recall. o Temporal discrimination (i.e. can’t tell which item they saw recently). Lack insight and retrograde problems (due to poor retrieval). Rupture of anterior communicating artery: o 30 – 40% of all ruptured aneurysm. o Memory impairment secondary to rupture or surgical intervention. o Damage occurs outside limbic regions. o Most frequent lesion site involves aspects of frontal lobes. Memory disorders Memory tests  Anterograde: o List learning tasks.    o Short stories. o Visual reproduction. o Rey complex figure. o Doors and people test. Retrograde: o Famous faces test. Working memory: o Digit span/LNS. o Mental control. o Arithmetic. Semantic memory: o Pyramid and Palm Tree’s Test (naming and vocabulary).