Stroke Scenario- Physiology Flashcards
What are the 3 main areas of the brain + what connects the brain to the spinal cord?
Cerebrum, Cerebellum and brain stem.
Foramen magnum is an opening at the base of the skull connecting the brain to the spinal cord.
What are the 3 coverings of the brain + their features?
Pia mater: innermost layer, directly continuous with brain and spinal cord, vascular which blood vessels pass through to internal CNS to nourish neural tissue.
Subarachnoid space: middle layer, contains cerebral arteries.
Dura mater: outermost tough layer, composed of 2 layers, innermost is the meninges.
What is the structure of the cerebrum?
Largest part of brain consisting of 4 lobes:
Frontal
Parietal
Temporal
Occipital
Cortex (surface) contains the centres from which motor impulses are carried to muscles and to which sensory impulses come from sensory nerves.
It contains the thalamus in the inner core.
What is the structure and function of the thalamus?
composed of 2 ovoid(egg shaped) structures.
Important relay station in the brain.
All main sensory pathways form synapses with thalamic nuclei on their way to cerebral cortex.
Pathways also serve as vehicles for transmitting pain, emotions etc.
What is complimentary specialisation?
a concept that determines that different areas of the brain serve different functions.
What are the functions of the cerebral hemispheres?
The categorical hemisphere is associated with:
language comprehension skills
sequential analytic processes.
The representational hemisphere is associated with:
recognition of faces, music and visual spatial relationships.
Where is the categorical hemisphere generally located + what important areas does it contain?
Left hemisphere for 96% of right-handed people.
Contains :
Wernicke’s area - area for language comprehension
Broca’s area - area for speech and word formation.
Injury to this hemisphere associated with language disorders.
What is the function of the cerebellum and where is it located?
It regulates coordinated activities such as gait and performance of motor tasks.
Located below and behind the cerebrum.
What structures does the brain stem contain?
Midbrain
Pons
Medulla oblongata
How are the cerebellum and brain stem connected?
Midbrain connects pons and cerebellum with the cerebral hemispheres.
Where is the pons located and what is it’s function? (Cerebellum)
Pons located in front of cerebellum between midbrain and medulla.
Serves as a bridge between 2 halves of cerebellum as well as between medulla and cerebrum.
It contains important centres for controlling heart, respiration, BP.
What is the function of the frontal lobe?
Contains areas associated with emotional attitudes and development of thought processes.
How are nerves structured in the cortex and how is this important in stroke?
Nerve fibres from all portions of cortex converge in each hemisphere and make their exit in the form of tight bundles ‘internal capsule’.
These cross the corresponding bundle from the opposite side therefore, a right-sided stroke = left-sided weakness.
What is cerebrospinal fluid and where is it located?
Cerebrospinal fluid is a clear fluid that bathes the surface of the brain and spinal cord, providing protection and supplying nutrients to the tissue of the nervous system.
It extends from the ventricle through narrow tubular openings.
Average amount of CSF is 150ml.
What are neurons and what are they composed of?
The structural, genetic and functional unit of the nervous system. They are composed of: cell bodies dendrites axons
Where are the cell bodies of neurons located?
Located in the layers on the surface of the brain and comprise gray matter.