Injury to the Cerebral Hemispheres and Cognitive Function

Question 1

The dorsolateral prefrontal areas of the frontal lobe are associated with what functions?

Answer 1

Executive function:

• Self-monitoring
• Planning and problem-solving

Question 2

The polar and orbitofrontal prefrontal areas of the frontal lobe are associated with what characteristics?

Answer 2

• Personality
• Social behaviour

Question 3

How do the functions of the primary motor cortex and premotor area differ?

Answer 3

• Cortex - voluntary limb movement, somatotopic organisation
• Premotor area - voluntary trunk movement

Question 4

What type of movements does the supplementary motor area control?

Answer 4

Complex and bimanual movements

Question 5

Which parietal lobe is involved in numeracy and goal-directed movement, “praxis”, in most people?

Answer 5

• The dominant parietal lobe is responsible for numeracy and praxes
• The left parietal lobe is dominant in most people

Question 6

The nondominant parietal lobe is involved in what function?

Answer 6

• Spatial relations
• Lesions of this area cause hemispatial neglect

Question 7

What is cortical blindness and how is it caused?

Answer 7

• Blindness due to damage in V1, the primary visual cortex
• Usually damage is caused by a stroke in the posterior cerebral artery

Question 8

What are (cerebral) achromatopsia and akinetopsia?

Answer 8

• Achromatopsia - acquired colour blindness due to cerebral damage in extrastriate visual association areas
• Akinetopsia - acquired inability to visualise motion due to cerebral damage in visual cortex and visual association areas, possibly V1 and V5

Question 9

What is amnestic syndrome and how is it caused?

Answer 9

• Inability to store new information despite full awareness - patients repeat the same statements or questions
• Caused by damage to critical parts of the limbic system

Question 10

Describe the timescales and other clinical indicators for a specific type of brain injury.

Answer 10

• Infarction - develops over seconds
• Haemorrhage - develops over minutes, hypertension
• Infection - develops over hours, systemically unwell, fever, tachycardia, confusion
• Inflammation - develops over hours to days, young patients, multiple lesions
• Neoplasia, develops over weeks
• Degeneration - develops over months to years, age-related

Question 11

What is posterior cortical atrophy (PCA)?

Answer 11

• PCA is an atypical variant of Alzheimer’s
• Relative preservation of cognitive function
• Decline in visuospatial and visuoperceptual capabilities
• Symptoms may include difficulty reading, blurred vision, impaired depth perception

Question 12

What is frontotemporal dementia?

Answer 12

FTD classified into 3 groups based on signs and symptoms:

1. Progressive non-fluent aphasia (PNFA) - loss of speech-related functions
2. Behavioural variant (bvFTD) - personality changes, emotional blunting, loss of empathy
3. Semantic dementia (SD) - loss of semantic memory - memory of facts, ideas, meaning and concepts