Which of the following can be used to test premorbid IQ in patients with neurological damage?
A. The National Adult Reading Test (NART) has been widely used as a measure of premorbid IQ. The usefulness of NART as a measure of premorbid IQ is based on two assumptions:
Hence in those with brain damage, irrespective of the diagnosis, NART can be used to estimate the most probable IQ level before becoming ill. However, the notion that the NART score is relatively independent of brain damage has come under scrutiny of late. Studies in Alzheimer’s dementia and Korsakoff’s syndrome have indicated deterioration in reading ability, leading to an underestimated premorbid IQ.
Reference:
A 55-year-old man with history of long-standing, untreated hypertension is brought to A&E by his wife following 3 hours of ‘confusion’. He was repeatedly questioning her and was not able to remember what he was doing 30 minutes ago. He is also unaware of events of the past 2 weeks, despite remembering them until 3 hours ago. Neurological examination is otherwise unremarkable and he has no psychiatric history. The episode resolves by itself within 24 hours.
Which of the following is false with regard to his condition?
D. This history is consistent with transient global amnesia (TGA). Sudden-onset amnesia with inability to form new memories of current events and a variable degree of retrograde amnesia is seen. The entire episode lasts for hours to days and on recovery the extent of retrograde amnesia shrinks and almost intact memory for events that happened before the episode is restored, but a dense amnesia persists for the events during the episode (24 hours in this case) even after full recovery. During the episode itself, the procedural memory, visuospatial functions, and problem-solving ability are intact; the patients may even be able to drive during the episode.
Abnormalities in which of the following vascular territories is implicated in this presentation?
C. TGA is thought to be vascular in origin. Posterior cerebral circulation (vertebrobasilar insufficiency) is implicated, which supplies significant part of hippocampal and other medial temporal regions. Migrainous or epileptic aetiology has not been entirely disproved. Obstruction to cortical sinuses may be related to idiopathic intracranial hypertension in some cases. The middle meningeal artery may be injured in skull fractures, often becoming a source of extradural haematoma.
A patient with long-standing, uncontrolled type 2 diabetes presents with anterior spinal artery occlusion.
Which of the following sensations carried by the spinal cord is most likely to be affected?
C. The anterior spinothalamic tract is supplied by the anterior spinal artery. The spinothalamic tract carries pain and temperature sensations. Posterior tracts such as dorsal columns of gracilis and cuneatus carry joint sense, light touch, proprioception, and vibration sensations. Infarction of the spinal cord usually involves the territory of the anterior spinal artery—the ventral two-thirds of the spinal cord.
Which of the following structures is a part of cerebellum?
A. The cerebellum has an external cortical grey matter and the deep cerebellar nuclei. There are four deep nuclei: dentate, globose, emboli-form, and fastigial nuclei. Mossy fibres and climbing fibres provide the major input into the cerebellum. Substantia nigra and subthalamic nucleus are part of basal ganglia. Red nucleus is an upper brainstem nucleus seen at the level of tegmentum. Similar to substantia nigra, red nucleus also contains iron pigments. It is involved in motor coordination.
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