Higher cortical function Flashcards
Describe the outputs of the cortex. (5)
Most outputs are the axons of pyramindal neurones (just the cell body shape) (eg UMN in the primary motor cortex are pyramidal).
They can form projection fibres (down to the brainstem / spinal cord), commisural fibres (between hemispheres) or association fibres (connecting bits of cortex in the same hemisphere).
Describe the imputs to the cortex. (1)
Most imputs come from the thalamus and other cortical areas.
Describe the functions of the frontal lobe. (12)
Motor - primary motor cortex here.
Speech - Broca’s area
Behavioural regulation - prefrontal cortex moderates behaviour.
Cognition and problem solving - prefrontal cortex.
Eye movements - conjugate eye movements.
Continence - paracentral lobules.
Describe the functions of the parietal lobe. (8)
Sensory - primary sensory cortex.
Comprehension of speech - Wenicke’s area.
Body image and awareness of external environment - hemispatial neglect
Calculation and writing
Superior optic radiations.
Describe the functions of the temporal lobe. (7)
Hearing - primary auditory cortex here
Olfaction - primary olfactory cortex
Memory - hippocampus
Inferior optic radiations
Describe the concept of cerebral lateralisation. (4)
Some function so are represented more fully in one hemisphere:
In 95% of people, the left hemisphere is dominant for language and mathematical/logical functions.
In 95% of people, the right hemisphere is dominant for body image, visuospacial awareness, emotion and music.
Describe what might occur if the corpus callosum is damaged. (1)
Alien hand syndrome
Describe Broca’s area and it’s functions. (4)
Sits in the inferolateral frontal lobe near the mouth-pharynx bit of the motor cortex.
It acts as the pattern generator, instructing the muscles of the pharynx and mouth to move in the right order to produce speech.
Describe Broca’s aphasia. (4)
Complete understanding but with an inability to form words in sentences. Described as staccato, an expressive dysphagia.
Describe Wenicke’s area and it’s functions. (3)
Sits at the parietotemporal junction, close to the primary auditory cortex in the temporal lobe. Responsible for the comprehension of speech.
Describe Wernicke’s aphasia. (4)
Nonsensical speech where the patient speaks clearly, but doesn’t appear to understand words they’re told or have the ability to response to them. A receptive aphasia.
Describe the language consequences with a middle cerebral artery infarct. (2)
Global aphasia - affects both Broca’s and Wernicke’s.
Describe the connections between Broca’s and Wernicke’s areas. Describe the consequences of damage here. (5)
The accurate fasiculus is a unidirectional white matter path that runs from Wernicke’s to Broca’s. Damage to this pathway most commonly leads to inability to repeat a heard word, but can also be unable to speak thoughts or read writing outloud.
Describe the differences between memories of facts and memories of skills. (6)
Declarative or explicit memories are factual, and are stored all around the cortex.
Non-declarative or implicit memories are emotions or motor skills and are stored in subcortical structures eg the basal ganglia and brainstem.
Describe the evolutionary advantage of storing memories in a wide variety of places in the CNS. (1)
It would be rare that a lesion compatible with life would destroy all memories.
