Lecture 6 Functional Organisation Of The Cortex Flashcards
From which surface of the Brain, can the central Sulcus be seen?
Lateral and medial
What do the gyri flanking the calcarine sulcus contain?
The primary visual cortex
What gyrus is continuous with the cingulate gyrus posterior to the splenium of the corpus callosum?
Parahippocampal gyrus
What lies deep to the parahippocampal gyrus?
Hippocampus
The hippocampus lies within which lobe?
The temporal lobe
What is the hippocampus associated with?
Memory
What connects the parahippocampul gyrus and the cingulate gyrus, and where can it be seen?
Isthmus, posterior to the splenium of the corpus callosum
What is the uncus associated with?
Smell
What is the course of association fibres to form a memory?
A bundle of association fibres run from the frontal lobe (Associated with organising movement and behaviour,) passes into the parietal lobe (Part of the sensory cortex,) passes past the visual cortex, then round to the uncus and into the hippocampus
What is the limbic lobe made up of?
The cingulate sulcus and gyrus, the parahippocampal gyrus, the collateral sulcus and the uncus
What separates the parahippocampal gyrus from the rest of the temporal lobe?
The collateral sulcus
How many brodmann areas exist in the brain?
46
What is meant by a primary projection sensory area?
Specific sensory pathways terminate here
What is meant by primary projection motor area?
Specific motor pathways originate here
Where is the general sensory primary projection area?
Post central gyrus
Where is the visual primary projection area?
Striate cortex
Where is the primary projection auditory area?
Superior temporal gyrus
What is meant by Heschl’s gyrus?
Superior temporal gyrus
Where is the olfactory primary projection area?
Uncus
Where is the gustatory primary projection area?
Inferior post-central gyrus
Where is the primary motor cortex, and what is meant by this?
Pre-central gyrus, every single muscle in the body is innovated via a neuron from the pre-central gyrus
What is meant by the statement “The post-central gyrus is somatotopically organised”?
Specific parts of the post-central gyrus receive input from specific parts of the body (Via specific, thalamic nuclei.)
Sensory input from which 3 structures, projects to the midline of the post-central gyrus?
Foot, toes and genitals
The lateral ventroposterolateral nucleus of the thalamus receives input from what part of the body and projects to what part of the post-central gyrus?
Lateral VPL receives input from the leg and projects to the midline
The medial VPL nucleus of the thalamus receives input from what part of the body and projects to which part of the post-central gyrus?
Receives input from the arm and projects to the lateral region
The ventroposteromedial nucleus of the thalamus, receives input from what part of the body? And projects to what part of the post-central gyrus?
The face and to the lateral region
Is the pre-central gyrus arranged in a similar way to the post-central gyrus? And what is meant by this?
Yes, axons to specific muscles in specific parts of the body originate from specific parts of the pre-central gyrus
What is meant by a secondary or association sensory area?
This area receives input from the primary sensory area and is involved in interpretation and understanding
Where are association areas normally located?
Close to the primary areas
What is meant by secondary or association motor areas?
This area sends output to the primary motor area and is involved in organising the patterns of movement
Where is the general sensory association area located?
Superior parietal lobe
Where is the auditory association area located
The lateral fissure/ superior temporal gyri
Who is the safest?
Jake Norman
Where is the pre-motor association area located?
Anterior to the pre-central sulcus on the lateral surface
Where is the supplementary motor area located?
Anterior to the pre-central sulcus on the medial surface
Where is the frontal eye field located?
Anterior to the pre-motor area
What does the frontal eye field do?
Controls the eyes
Whats is the supplementary motor area to do with?
Stability
What is meant by the word equipotential?
The left does the same as the right. This is true for general functions
Is functioning equipotential for higher functions?
No, for higher functions, you have cerebral dominance
For sensory and motor association areas, is functioning equipotential?
Yes
What does damage to secondary sensory areas lead to?
Disorders of understanding
What is meant by agnosia?
A disorder of understanding due to damage to a secondary sensory area, an awareness of the sensation persists but the significance of the sensation is lost, for example if you held an object with your eyes closed, you would know you were touching something but you wouldn’t be able to recognise what it was
What does damage to a secondary motor area lead to?
An inability to carry out purposive movements, but there is no paralysis. Leads to an inability to perform learned movements
What is meant by apraxia?
An inability to carry out purposive movements, due to damage to a secondary motor area
What is the general association cortex involved in?
More complex aspects of behavioural and intellectual functioning
In terms of the general association cortex, what is the parieto-temporal cortex involved in?
It’s involved in memory, it integrates information of different modalities
In terms of the general association cortex, what is the pre-frontal cortex involved in?
Regulates moods and feelings, involved in higher order cognitive functions, such as conceptualisation, planning and judgement
What is meant by the statement “As you ascend the hierarchy of cortical function lateralisation of some functions occurs”?
In terms of higher functions, such as linguistic function, there is cerebral dominance i.e. lateralisation of function
Where is the auditory association area found?
In one hemisphere, specialised for linguistic function, usually the left hemisphere
Which hemisphere is said to be the dominant hemisphere?
The left hemisphere, this is related to handedness i.e. left motor function controls the right limb
What is the non-dominant hemisphere concerned with?
Spatial awareness
Which two specific areas on the left hemisphere are involved in language?
one is Wernick’s area, the other is Broca’s area
Does Wernick’s area lie anteriorly or posteriorly in the left hemisphere? And what is it to do with?
Wernick’s area lies posteriorly and is sensory or receptive, so to do with understanding
Does Broca’s area lie anteriorly or posteriorly in the left hemisphere? And what is it to do with?
Broca’s area lies anteriorly and is motor-expressive, so to do with production of speech
Damage to Wernick’s area, results in what kind of Aphasia?
Receptive Aphasia i.e. an inability to understand language
Damage to Broca’s area, results in what kind of Aphasia?
Expressive Aphasia i.e. an inability to correctly articulate speech
