Functional Neuro Anatomy (CNS and PNS cont.) Flashcards
What is the function of the corpus collosum?
It is a white matter tract that shares information between the forebrain cerebral hemispheres. This is a transference of information.
What is lateralisation in the brain? what is an example?
This is a term meaning that the two hemispheres are specialised or lateralised to specific tasks.
e.g. The left hemisphere is predominantly stronger in performing language based tasks.
What is it called when the left hemisphere controls the right body, and the right hemisphere controls the left body? where is this prominent?
This is called a contralateral arrangement. This is prevalent in the cerebral hemispheres.
What is another example of contralateral arrangement in the brain?
Our visual system.
How does our visual system function?
When we see visual information we have a point in the middle of our field called a fixation point.
Anything to the left is, left visual field.
Anything to the right, is right visual field.
Both left and right visual fields are processed in BOTH eyes simultaneously.
What is the structure responsible for contralateral arrangement in the visual system? what happens at this point?
It is a white matter tract called the optic chiasm.
This is the point where left visual information is passed to the right cerebral hemisphere and where right visual information is passed to the left cerebral hemisphere.
What is the significance of the optic chiasm when conducting visual experiments?
Its arrangement is crucial in understanding how the cerebral hemispheres are organised and lateralised.
How does lateralisation work in split brain patients?
They process information the exact same way as someone who doesn’t have a split brain, however due to the corpus callosum being severed their right brain cannot provide language (speech) for what they have seen in their left visual field. This confirmed ideas that the left cerebral hemisphere is lateralised for language and speech and the right hemisphere seemed to be better at visuo-spacial tasks.
What are ventricles?
They are fluid filled chambers within the brain willed with cerebrospinal fluid (CSF), all together they are called the ventricle system.
How is CSF produced?
It is produced by a specialised tissue in the cerebral ventricles called the choroid plexus.
What is CSF responsible for?
Buoyancy
Producing half a litre of fluid per day.
Works as a mechanical shock absorber circulating over the brain through the sub-arachnoid space.
What are meninges? what are thier layers?
Protective sheaths around the brain and the spinal cord that have three layers that exist between the internal surface of the skull and the surface of the cerebral cortex.
- Dura Mater (Hard mother)
- Arachnoid membrane
- Pia Mater (Soft mother)
What is the sub-arachnoid space?
It exists between the pia mater and the arachnoid membrane. They are critical as a brain support system.
What are capillaries?
Tiny blood vessels in the tissue that have very tight junctions. They make it easier for large molecules to move from the blood into the brain tissue. They also protect the brain by preventing toxins from circulating there.
What are the main arteries in the brain?
Carotid artery, that run along our neck into our brain tissue.
Anterior cerebral artery
Middle cerebral artery
Posterior cerebral artery
