8.1 higher cortical function Flashcards
where are most inputs and outputs to and from the cerebral cortex from?
inputs = from thalamus and other cortical areas
outputs = from pyramidal cells and project to widespread areas. can be projection fibres e.g UMN fibres, can be commissural fibres e.g corpus callosum or can be association fibres e.g arcuate fasiculus.
what is the function of the frontal lobes?
Motor (primary motor cortex, damage can result in contralateral weakness)
Expression of speech (L hemisphere usually).
Broca’s area is here. Damage can cause dysphasia
behavioural regulation/judgement. Prefrontal cortex is here. damage = impulsive, disinhibited behaviours.
cognition. prefrontal cortex is here. can get difficulty with tasks like complex problem solving e.g calculations.
eye movements. contain frontal eye fields.
continence (paracentral lobules)
what is the function of the parietal lobes?
Sensory. Has primary sensory cortex. Damage = can get contralateral anaesthesia affecting all modalities.
Comprehension of speech. Wernickes area. Can cause receptive dysphasia
body image and awareness of external environment. damage can lead to neglect.
calculations and writing, working with the frontal love.
REMEMBER superior optic radiations run through here = damage can cause a contralateral inferior homonymous quadrantanopia.
how many layers make up the cerebral cortex?
6 layers containing cell bodies and dendrites (its grey matter)
where is the primary motor and sensory cortex found?
motor cortex = frontal lobe
sensory cortex = parietal lobe
what are the functions of the temporal lobe?
HOME
Hearing. Primary auditory cortex on the superior surface, near wernickers area. Auditiory hallucinations = a sign of a leison
Olefaction. Primary olfaction cortex here. olefactory hallucinations are a sign
Memory. Hippocampus is a crucial structure for this. Damage can lead to amnesia.
Emotion.
REMEMBER inferior optic radiations run here. damage can lead to a contralateral superior homonymous quadrantanopia.
what is the left hemisphere usually dominant for?
sequential processing
- language
- mathematics/logic
what is the right hemisphere usually dominant for?
whole picture processing
- body image
- visuospatial awareness
- emotion
- music
what is the corpus callosum?
a huge bundle of white mater connecting the two hemispheres.
what effect can destruction of the corpus callosum have?
alien hand syndrome
subtle effects on language processing
where is the visual cortex located?
the occipital lobe
what is broca’s area and where is it found?
it is in the inferior lateral frontal love
Sits just inferior to the mouth/pharynx area of the primary motor cortex (on the lateral part of the pre central gyrus)
responsible for speech production. A pattern generator.
what can damage to Broca’s area cause?
staccato speech, where patient still understands what is being said to them
= Brocas/ expressive dysphasia
what is wernickes area and where is it found?
found at the parieto-temporal junction
sits near primary auditory cortex in temporal lobe (good as can send to wernickes area immediately for interpretation)
for interpretation of language
what can damage to wernickes area cause?
damage can cause fluent, nonsensical speech where the patient doesn’t appear to understand what is beingg said to them
= receptive dysphasia
how are wernickes and brocas area connected?
via the arcuate fasiculus (white matter)
what is the pathway for repeating a heard word?
goes from ear to primary auditory centre in temporal lobe
from there goes to wernickes area at parietal- temporal junction to understand word
then through arcuate fasiculus to brocas area to form pattern to repeat word
from there goes to motor cortex for face to say word
where do inputs for a thought come from?
all over the cerebral cortex
what can be the consequence if the arcuate fasciculus is damaged?
can cause the inability to repeat heard words
where are memories believed to be stored?
all over the brain
what is declarative/explicit memory? where is is stored?
- factual information
tends to be stored in cerebral cortex
what is non declarative/implicit memory? where is it stored?
- motor skills
- emotion
tends to be stored in subcortical structures e.g basal ganglia and cerebellum
where is short term memory stored? where is it stored?
stored for seconds to minutes as reverberations or echo in cortical circuits
where is long term memory stored?
in cerebral cortex, cerebellum etc. following consolidation
what factors effect consolidation?
- emotional context
- rehearsal : how familiar you are with the info
- association
what is the importance of the hippocampus in memory?
helps consolidate memories
sits deep in temporal lobe
has lots of inputs from many brain systems = good at associating stimuli
