cortical organisation and function - cerebral cortex Flashcards
what is the cerebral cortex
covers entire brain
contains grey matter
organised in lobes
what are gyri
ridges
what are sulci
valleys
what are the layers in the cerebral cortex
molecular layer external granular layer external pyramidal layer internal granular layer internal pyramidal layer multiform layer
how many regions is the brain organised into according to brodmann
52 regions
based on cytoarchitecture
what is the function of the frontal lobe
regulates and initiates motor function language cognitive function e.g planning attention memory
what is the function of the parietal lobe
sensation - touch, pain..
sensory aspects of language
spatial orientation and self perception
what is the function of the occipital lobe
processing visual information
what is the function of the temporal lobe
processing auditory info
emotions
memory
what can you find in the limbic lobe
amygdala
hippocampus
mamillary body
cingulate gyrus
what is the limbic lobe concerned with
learning memory emotion motivation reward
where can we find the insular cortex
lies deep within lateral fissure
what is insular cortex concerned with
visceral sensations autonomic control interoception auditory processing visual - vestibular integration
what is grey matter
neuronal cell bodies and glial cells
approx 85 bill of each
what is white matter
myelinated neuronal axons arranged in tracts
what are white matter tracts
they connect cortical areas either within same hemisphere or diff hemispheres
what are the 3 types of white matter tracts
association fibres
commisural fibres
projection fibres
what are association fibres
connect areas within the same hemispheres
what are commissural fibres
connect homologous structures in left and right hemisphere
what are projection fibres
connect cortex with lower brain structures e.g thalamus, brainstem, spinal cord
what is the superior longitudinal fasiculus
connects frontal and occipital lobes
what is the arcuate fasiculus
connects frontal and temporal lobes
what is the inferior longitudinal fasiculus
connects temporal and occipital lobes
what is the small uncinate fasiculus
connects anterior frontal and temporal lobes
what are the commissural fibres
corpus callosum
anterior commissure
what are primary cortices
predictable function
organised topographically
symmetry between left and right
what is the secondary/association cortices
less predictable function
not organised topographically
left- right symmetry weak/absent
what are some motor areas found in frontal lobe
primary motor cortex
supplementary area
premotor area
what is the role of primary motor cortex
controls fine,discrete,precise voluntary movements e.g dextrous movements
provides descending signals to execute movements
what is the supplementary area
involved in planning complex movements e.g internally cued e.g speech
what is the premotor area
involved in planning movements e.g externally cued e.g picking up an object
what are the areas found int he parietal lobe
primary somatosensory cortex
and somatosensory association
what is the role of the primary somatosensory cortex
processes somatic sensations arising from receptors in body
what are some of the sensations that can be delivered to primary somatosensory cortex
fine touch vibration proprioception pain temp 2 point discrimination
what is role of somatosensory association
interpret significance of sensory info e.g recognising object
awareness of self and personal space
what are the occipital lobe areas
primary visual and visual association
what is role of primary visual cortex
processes visual stimuli
what is role of visual association
gives meaning and interpretation of visual input
what are areas in temporal lobe
primary auditory
auditory association
what is role of primary auditory cortex
processes auditory stimuli
what is role of auditory association
gives meaning and interpretation of auditory input
what are some other association areas
prefrontal cortex
brocas area
wernickes area
what is role of brocas area
production of language
what is wernickes area
area where understanding of language takes place
what is role of prefrontal cortex
attention adjusting social behaviour planning personality expression decision making
what can frontal lobe lesions cause
changes in personality
inappropriate behaviour
what can parietal lobe lesions cause
contralateral neglect
lack of self awareness
lack of extrapersonal space
what can temporal lobe lesions
leads to agnosia - inability to recognise
could lead to anterograde amnesia - cannot form new memories
what can lesion to brocas area cause
expressive aphasia - poor production of speech
comprehension intact
what can lesions to wernickes area cause
recptive aphasia - poor comprehension of speech
production is fine
what can lesion to primary visual cortex cause
blindness in corresponding part of visual field
what can lesion to visual association cause
deficits in interpretation of visual info
e.g prosopagnosia: inability to recognise/learn new faces
what can we use a pet scan to see
blood flow directly to brain region
what can we use a fMRI for
to see amount of blood oxygen in a brain region
what can we use an eeg for
measures electrical signals produces by brain
what is an eeg
electroencephalography
what is an meg
magnetoencephalography
what can we use an meg for
measures magnetic signals produced by brain
what can we use trancranial magnetic stimulation for
assess functional integrity of neural circuits
uses electromagnetic induction to stimulate neurons
what is transcranial direct current stimulation
uses low current over scalp to increase/decrease neuronal firing rates
what is a diffusion tension imaging (dti)
based on diffusion of water molecules
what is dti with tractography
3d reconstruction to assess neural tracts
