Control lecture 1: Introduction to the human brain Flashcards
What is the name of the cleft separating the cerebral hemispheres?
The great longitudinal fissure.
Where would you find grey matter and white matter?
Grey matter lies on the surface of the brain, white matter is deep to this.
What are the names of the folds and grooves on the surface of the cerebral hemispheres?
Fold = gyrus (gyri) Groove = sulcus (sulci)
What is the function of the sulci/gyri and what is their significance in humans?
Increase surface area of brain. Allow us to feel more complex emotions - only seen in humans.
Which lobes are divided by the central sulcus?
Frontal from parietal.
Which lobes are divided by the lateral sulcus?
Frontal/parietal from temporal.
What is the name name of the gyrus anterior to the central sulcus and which cortex is found here?
The precentral gyrus.
Primary motor cortex - every single motor axon originates here.
What is the name of the gyrus posterior to the central sulcus and what cortex is found here?
The postcentral gyrus.
The primary somatosensory cortex - recieves all sensory input.
Which gyrus is found inferior to the lateral sulcus and what cortex is found here?
The superior temporal gyrus - the primary auditory cortex.
What is the name of the sulcus the separates the parietal lobe from the occipital lobe?
The parieto-occipital sulcus.
Which cortex is found at the most posterior aspect of the occipital lobe?
The primary visual cortex.
Which sulcus runs diagonally across the medial surface of the occipital lobe?
Calcarine sulcus
What are the divisions of the diencephalon?
Thalamus
Hypothalamus
Epithalamus
Subthalamus
What is the function of the thalamus?
- Relay station between between brainstem, spinal cord and cerebral cortex.
- Also has roles in: memory, alertness, consciousness, perception and cognition
What is the function of the hypothalamus?
Controls the ANS.
Controls hunger, thirst, body temperature, sexual activity, circadian rhythms, blood pressure/HR (see also medulla oblongata) etc…
What are the divisions of the brainstem?
Midbrain, pons and medulla oblongata.
What primary brain vesicle does the forebrain develop from?
The prosencephalon.
Which primary brain vesicle does the midbrain develop from?
The mesencephalon.
Which primary brain vesicle does the hindbrain develop from?
Rhombencephalon.
Describe the development of the cerebral hemispheres.
Prosencephalon -> telencephalon -> cerebral hemispheres
Describe the development of the diencephalon.
Prosencephalon -> diencephalon -> diencephalon.
Describe the development of the midbrain
Mesencephalon -> mesencephalon -> midbrain.
Describe the development of the pons and cerebellum.
Rhombencephalon -> metaencephalon -> pons and cerebellum
Describe the development of the medulla oblongata.
Rhomencephalon -> myelencephalon -> medulla oblongata
Give a summary of CNS development.
- Adult CNS from hollow neural tube.
- Five swellings develop at rostral end.
- Each forms a subdivision of adult brain.
- Rest of tube forms spinal cord. Cavity of tube persists in different degrees of expansion throughout tube:
Ventricles – expanded cavities within the brain Connecting channels – link ventricles Vestigial – central canal of spinal cord
What are the features of the dura?
- Tough, fibrous membrane
- Ensheathes brain like loose fitting bag
- Two large reflections of dura extend into the cranial cavity between the cerebral hemispheres (falx cerebri), and cerebrum and cerebellum (tentorium cerebelli).
What are the features of the arachnoid?
- Soft translucent membrane
- Also surrounds the brain
- Space between arachnoid and dura = subdural space (very small)
What are the features of the pia?
–Microscopically thin, delicate membrane
–Tightly adhered to the surface of the brain, following all cavities
What is the subarachnoid space?
Space between the pia and arachnoid that contains CSF.
What are the layers of the dura?
Periosteal (superficial) and meningeal (deep).
At what points are the layers of the dura not fused together?
Dural venous sinuses and various infoldings.
How does venous blood drain from the brain?
Into the dural sinuses and then the internal jugular vein.
What is the function of the 4th ventricle?
Creates and stores CSF.
What is the falx cerebri?
Infolding of the dura between the cerebral hemispheres.
What is the tentorium cerebelli?
Dural infolding between occipital lobes and cerebellum.
What is the falx cerebelli?
Dural infolding between the cerebellar hemispheres.
What is the function of the dural infoldings?
Location of various venous sinuses. Recieve venous blood from the brain and drain into the jugular vein.
What percentage of bodily oxygen is consumed by the brain?
20%.
What are the two pairs of arteries that supply the brain?
The vertebral artery and the internal carotid.
What is the origin of the vertebral artery?
The subclavian.
Where does the verterbal artery enter the skull?
Via the foramen magnum.
What is the origin of the internal carotid?
The common carotid.
Where does the common carotid enter the skull?
The carotid canals.
What are the three pairs of cerebellar arteries?
Posterior inferior cerebellar
Anterior inferior cerebellar
Superior cerebellar
What are the three pairs of cerebral arteries?
Posterior cerebral
Middle cerebral
Anterior cerebral
