Central Nervous System Flashcards
What are the large section of the brain?
Forebrain (prosencephalon) - split into telencephalon and diencephalon
Midbrain - Mesencephalon
Hindbrain (Rhombencephalon) split into metencephalon and myelencephalon
What makes up the diencephalon of the forebrain?
Thalamus – important relay nucleus from sensory modalities to the cortex (used for recognising pain)
Hypothalamus – involved in homeostasis (hormone levels and blood pressure) and endocrine functions
Pituitary gland – important for release of hormones etc
Limbic system - a collection of structures involved in mood, emotion
What makes up the Telecephalon of the forebrain?
Cerebral hemispheres (cerebral cortex, neocortex) - “higher functions", where we can actually recognise pain (no longer just an electrical impulse) Basal ganglia - part of extrapyramidal motor system, corpus striatum, caudate nucleus important in motor disorders More “limbic system”
What makes up the hindbrain (Rhombencephalon)?
Brain stem: medulla oblongata, pons and midbrain Cerebellum Reticular formation Raphe nuclei Area postrema Locus coeruleus in pons
How can we catagorise the postion of different sections of the brain?
Front of the body: anterior or ventral Back of the body: posterior or dorsal Head of the body: rostral or superior Tail of the body: caudal or inferior Near to the midline: medial Further from the midline: lateral
What are the planes that we can view sections of the brain from?
Coronal - left to right
Horizontal - plane through the circumference
Sagittal - through the middle of your forehead (like a shark)
Why can we fit a lot into a human brain?
It isn’t smooth as it has sulcus (depressions/grooves in the cerebral cortex) surrounding gyrus
This forms the charcteristic ridges and folding of the brain
What are the lobes we can split the brain into?
Frontal lobe - conscious thought
Parietal lobe - integrating sensory information from various senses
Occipital lobe - sense of sight
Temporal lobe - homeostasis
What is the sensory homunculus?
A visual representation of how sensitive different areas of our body are, with the size of the area reflecting the degree of sensitivity
e.g. hands, lips and tongue were the most sensitive
What is the spinal cord?
A long, thin, tubular structure made up of nervous tissue It extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column
What does the spinal cord contain?
White matter (due to myelinated neurones) Grey matter Dorsal root Ventral root Sympathetic ganglion cells
What is the difference between a rat brain and a human brain?
The rat brain is smooth
A human brain has many more cells
However, the gross structures are very similar
What is the meninges?
The central nervous system is covered by three membranes:
Dura mater – thickest, external membrane which protects the CNS
Arachnoid mater – lies beneath the dura mater, space between upper two membranes is called subdural space. Does not enter sulci. Below is CSF
Pia mater – internal layer, lies on the surface of the brain and spinal cord. Enters sulci
