Control L9 localisation Flashcards
What is the thin layer of grey matter overlying the cerebral hemisphreres called?
Cerebral cortex
How many layers of context surround most of the cerebrum?
6 layers
What are properties if the cerebral cortex?
Heavily folded to increase surface area
Varied thickness of 2-4 mm
Has a laminar arrangement
Has specific sulci which divide the cerebral hemispheres into lobes and specific gyri
What gyri are separated by the superior frontal sulci?
The superior frontal gyri (superiorly) and the middle frontal gyri
What gyri are separated by the inferior frontal gyri?
The middle frontal gyri (superiorly) and the inferior frontal gyri (inferiorly)
What sulcus is inferior to the superior temporal gyri?
Superior temporal sulcus
What gyri are separated by the superior temporal sulci?
Superior temporal gyrus and middle temporal gyrus
What gyri is separated by the superior temporal sulci?
Superior and middle temporal gyri
What gyri is separated by the inferior temporal sulci?
Middle and inferior temporal gyri
What are 4 sulci seen on the medial view of the cerebrum?
Cingulate sulcus
Parietooccipital sulcus
Calcarine sulcus
Collateral sulcus
What gyri sits inferior to the consulate sulcus?
Where do the uncus and and parahippocampl gyrus sit?
On inferior portion of brain
What part of the cerebrum are part of the lambic system/limbic lobe?
Cingulate gyrus
Parahippocampal gyrus
Uncus
What function is controlled by the limbic lobe?
Emotion and memory
Where can the uncus herniate?
Under the tentorium cerebelli
What is caused by uncal herniation?
Compression of the brainstem
What type of herniation occurs into the foramen magnum?
Tonsillar herniation
What are broadmann’s areas?
The 46 areas of the brain based on cellular organisation of the cerebral cortex.
What are primary sensory areas?
Where specific sensory pathways terminate so where sensation is perceived.
What are primary motor areas?
Where specific motor pathways originate
What primary sensory area is associated with general sensation?
Post-central area
What primary sensory area is associated with visual?
The striate cortex either side of the calcarine sulcus and occipital pole
What sensory area is associated with hearing?
Superior temporal gyrus
What primary sensory area is associated with smell?
Uncus
What primary sensory area is associated with gustatory?
Inferior post central gyrus
What primary motor area is the primary motor cortex found?
Pre-central gyrus
What are secondary sensory areas?
Areas that receive input from primary sensory areas to help interpret and understand input.
What are secondary motor areas?
Areas of the brain which receive output from primary motor areas and organise patterns of movements.
What secondary sensory area is associated with general sensation?
Superior parietal lobe
What secondary sensory area is associated with vision?
Pre-striate area
What secondary sensory area is associated with hearing?
Lateral fissure and superior temporal gyrus
What secondary motor area is associated with the pre motor area?
Area anterior to the precentral sulcus on the lateral surface of the cortex
What secondary motor area is the supplementary motor area found?
Area anterior to the precentral sulcus on the medial surface of the cortex.
What secondary motor area is associated with the frontal eye field?
Area anterior to the pre motor area
What is the role of the primary motor cortex?
How will a patient present with damage to this area?
Controls voluntary contraction of somatic muscles. Is somatotopically organised. Damage can cause muscle paralysis.
Where and what are the supplementary motor and pre-motor areas?
How will a patient present with damage to this area?
Anterior to the primary motor cortex (supplementary superior to pre-motor) and controls learned complex motor activities (e.g. tying shoe laces) and store information on these activities. Sends signals to motor cortex which sends signal to the rest of the body.
Damage leads to inability to complete complex tasks.
Where and what is the frontal eye field?
In the frontal lobe (rostral to the pre-motor cortex) and controls voluntary scanning movements of the eyes
Where and what is the expressive speech/Broca’s area?
In the dominant hemispheres (typically left) in the inferior frontal gyrus. It regulates pattern of breathing and vocalisation needed for normal speech.
Where and what is the primary somatosensory cortex?
How is it organised?
In the post central gyrus and the area which receives sensory pathways for touch, temperature, vibration, pain and proprioception.
It is somatotopically organised
What information is sent to the VPL of the thalamus?
Sensation from the body below the neck
What information is sent to the VPN of the thalamus?
Sensation from the head and neck
Where is information received at the VPL and VPM of the thalamus sent?
To the post central gyrus (primary somatosensory cortex)
What order (laterally to medially) is sensory and motor information from the body organised in the somatosensory and motor homunculi?
Face, arm, trunk, legs
What lobes is the associated somatosensory area? What is its function?
The superior parietal lobe.
Interpretation, understanding and recognition of what is being sensed by the primary somatosensory cortex and special analysis.
What happens as a result of a lesion to the superior parietal lobe?
Tactile agnosia (can’t recognise things by touch alone)
What happens as a result of a lesion in the primary somatosensory cortex?
Anaesthesia (lack of sensation)
What area of the brain is the primary auditory cortex? What is its function and organisation?
Superior temporal gyrus aka Heschl’s gyrus.
Involved in conscious perception of sound and tonotopically organised (spectrum of audible frequencies mapped onto the primary auditory cortex)
What nuclei in the thalamus is involved in sending auditory information to the primary auditory cortex?
MG
What area is the association auditory cortex? What is its role?
The area of the brain surrounding the primary auditory area.
It interprets and gives significance to auditory information.
In which hemisphere is the receptive speech (Wernicke’s) area located?
In the dominant hemisphere (typically left)
Where is the primary visual cortex? What is its function? What nuclei of the thalamus is involved?
At the area around the calcarine sulcus and occipital pole.
To receive retinotopically organised from the retina.
LG - directs information from retina to the primary visual cortex
Where is the association visual cortex?
What is its function? How will a patient with a lesion to this area present?
Surrounding the primary visual cortex.
Interprets visual information e.g. facial, object recognition.
Prosopagnosia (inability to recognise faces)
Where is the taste cortex?
Inferior most aspect of the postcentral gyrus and into the insula.
What is the role of the general association cortex?
Involved in more complex aspects of behavioural and intellectual functioning.
What are two areas in the general association cortex?
The prefrontal cortex
The parieto-temporal cortex
What is the role of the prefrontal cortex?
To regulate mood and feelings
Involved in higher order cognitive functions like conceptualisation, planning and judgement
What is the role of the parieto-temporal cortex?
To integrate information from different modalities
Involved in memories
What functions are lateralised to the dominant hemisphere?
Linguistic function
Numerical skills
What function is lateralised to the non-dominant hemisphere?
Spatial awareness
What three types of aphasia can occur due to lesions within the dominant hemisphere?
Conduction aphasia
Receptive/Wernicke’s aphasia
Expressive (Broca’s) aphasia
How will a patient with conduction aphasia present?
Impaired repetition of words but comprehension of language and fluency intact (occurs due to damage to the arcuate fasciculus)
How will a patient with receptive (Wernicke’s) aphasia present?
With an inability to understand language but can still speak fluently - damage to sensory pathway
How does a patient with expressive (Broca’s) aphasia present?
With an inability to correctly articulate speech so understands but is not fluency - damage to motor pathway
what connects the areas of the brain involved in speech?
Arcuate fasciculus
