Cerebral Surface Flashcards
Difference in size of corresponding lobe and bone of the same name
Structures in the ethmoid bone
Olfactory nerves
Cribriform plate
Structures in the sphenoid bone
Pituitary gland
Diaphragm sella - meningeal dural fold
Importance of cerebrum
What is it responsible for
Contents of cerebrum
Newest (evolutionarily) and largest part of the brain as a whole
- Perception, thought, imagination, judgement, decision making
- Contains an outer surface/cortex and deeper grey matter areas termed SUBCORTICAL NUCLEI
What are subcortical nuclei
Deeper grey matter areas in the cerebrum (also some in the diencephalon)
Contents of diencephalon
Thalamus & hypothalamus
Some of subcortical nuclei of the brain
Describe the brainstem
The continuation of the spinal cord
Consists of medulla oblongata, pons and midbrain
What is the 2nd largest part of the brain
Cerebellum
Sagittal view of the brain
Why is the cerebral cortex known as “the seat of our intelligence”
Neurons in the cortex that we are able to read, write, speak, remember, and plan our life
What does the cerebrum consist of
An outer cerebral cortex
An internal region of cerebral white matter
Grey matter nuclei deep within the white matter termed Sub-Cortical nuclei
Define grey matter
- Grey because it lacks myelin
- Formed from neuronal cell bodies and dendrites
Define white matter
Formed from aggregations of myelinated axons from many neurons
The lipid part of myelin imparts the white appearance
Medial view of tracts revealed by removing grey matter from a midsaggital section
Influence of grey matter development on the formation of gyri and sulci
During embryonic development, the grey matter of the brain develops faster than the white matter - the cortical region rolls and folds on itself
Convolutions and grooves are created in the cortex during this growth process
Define gyri
Folds
Define fissures
Deepest grooves between gyri
Define sulci
The shallower grooves between folds
What does the longitudinal fissure separate
The cerebrum into right and left cerebral hemispheres
What does the central sulcus divide
The anterior frontal lobe from the more posteriorly situated parietal lobe
Where is the precentral gyrus located
What is contained in it
Immediately anterior to the central sulcus in the frontal lobe
Contains the primary motor area of the cerebral cortex
# Define the primary motor area Where is it found
- Where the sginal and fibres finally depart the cortex to exit via the spinal cord carrying signals to the hand e.g. allowing you to carry out your decision to lift a finger by contracting the relevant muscle
- Located in the precentral gyrus, immediately anterior to the central sulcus in the frontal lobe
Where is the postcentral gyrus located
What is contained in it
- Immediately posterior to the central sulcus in the parietal lobe
- contains the primary somatosensory area of the cerebral cortex
Define primary somatosensory area
- Where a signal that your finger touched the button first arrives in the cortex allowing you to perceive senses from the body
- Located in the postcentral gyrus, located immediately posterior to the central sulcus in the parietal lobe
Name the gyri
What is plasticity
The brain changes over a lifespan
What bone is associated with the external auditory canal/meatus
Temporal
How do the frontal bone & lobe compare
Frontal lobe is larger than the frontal bone
Where does the diencephalon sit
Medial and deep to the cerebral hemispheres
What is the thalamus
A major relay station for signals to get to the cortex
relays motor instructions from the cortex to the brainstem, spinal cord and the body’s muscles
What is in the brainstem
Brainstem contains nuclei that are critical to life ie cardiac and resp control areas
What is the cerebellum responsible for
Meta analysis of speech and physical task performance monitoring
Longitudinal fissure
Separates right and left cerebral hemispheres
What is the outer cerebral cortex/mantle composed of
Grey matter
What lies under the cortex
An internal region of cerebral white matter & grey matter deep within the white matter => SUB-CORTICAL NUCLEI
Central sulcus
Marks the boundary between the frontal and parietal lobe
Precentral gyrus
Primary motor cortex
Postcentral gyrus
Posterior to central sulcus
Primary somatosensory cortex
3 different types of cortex
Paleo - oldest
Archo - intermediate
Neo - newest
V1 in occipital cortex represents the primary termination zone of the visual pathway arising as the optic nerve in the retina
V1 is high in muscarinic 2 receptors - primary visual cortex and exists either side of the calcurine fissure
What happens when myelin is degraded and signal compromised
Disorders such as MS and difficulty controlling muscles
White matter is used to…
Carry signals between 2 grey matter regions
Can a function be assigned to a particular cortical area
We’re generalising when we do and potentially wrong
What is the faster grey matter growth (over white matter growth) due to
Mechanical forces of tissue with cranium being a limiting factor
