Module 3: Central Nervous System Flashcards
Where is cerebrospinal fluid (CSF) made?
In the choroid plexus (roof of ventricles)
What areas of the brain does the central sulcus seperate?
The frontal from the parietal lobe
what are the components of the CNS?
- spinal cord
- brain
what is the fuction of the CNS?
integrating signals and performing high cognitive fuctions
what cells are in the CNS?
- Neurons
- Neuroglia
what do neurons do in the CNS?
they are excitable cells that transmit electrical signals via synapses. They are the basic functional unit of the nervous system
what do neuroglia do in the CNS?
they are supporting cells, there’s 10x more than neurons, they support and insulate the neurons
what part of the neuron is grey matter?
the soma of the neuron
what part of the neuron is white matter?
the axon of the cell
name the 3 major regions of the brain
- cerebral hemisphere
- cerebellum
- brain stem
what are the 3 features of the brain stem?
- diencephalon
- pons
- medulla oblongata
what seperates the brain left to right?
the longitudinal fissure
what seperates the brain front to back?
the central sulcus
what’s the difference between a fissure and sulcus?
fissure=deep
sulcus=shallow
what is the name of the region ajacent to the central sulcus?
- precentral gyrus: motor
- postcentral gyrus: sensory
what % of brain is the cerebrum?
83%
what are the 4 lobes of the cerebrum?
- frontal
- parietal
- temporal
- occipital
what’s the name of the fissure that seperates the cerebrum to the cerebellum?
transverse cerebral fissure
what is the fuction of the frontal lobe?
primary motor area: voluntary movements
what is the function of the parietal lobe?
primary somasensory area: proprioception: awareness of own body
what does proprioception mean?
awareness of own body
what is the function of the occipital lobe?
primary visual cortex - sight
what is the function of the temporal lobe?
primary auditory cortex - hearing
what are the 3 matters of the cerebrum
- grey matter
- white matter
- Basal Nuclei: deep grey matter
how do the hemispheres interact?
contralaterally
what are the 3 functional areas of the cerebrum?
- motor area
- sensory area
- association area
what is the function of the motor area?
controls voluntary movement
what is the function of the sensory area?
concious awareness of self
what is the function of the assosiation area?
relays information between the motor area and sensory area through multiple inputs and outputs, via multiple sites of the brain
what is the left hemisphere dominantly in control of?
speech, writing, maths, logical processes and the right eye
what is the right hemisphere donimantly in control of?
how we are in the world, touch, spatial awareness, artistic, left eye
what is the right hemisphere dominantly in control of?
how we are in the world, touch, spatial awareness, artistic, left eye
what does dominant mean in the brain?
which side is used more e.g. left handed=right brain dominant
what are the 3 fibers in white matter of the brain?
- association: connect different parts of the same hemisphere
- commisural: connect grey areas of 2 different hemispheres (run transversly across the hemispheres, corpus callosum biggest)
- projection: veritcal tracts that connect the cerebral cortex with subcoritcal structures. (sensory and control motors move through these)
what is the function of the basal nuclei?
- receives input from from entire cerebral cortex
- controls skeletal muscle, cognition and emotion
list the features of the basal nuclei?
- caudate nucleus
- putamen
- globus pallidus
3.5. globus pallidus+tail of caudate nucleus=lentiform nucleus
what is the function of the basal nuclei?
unknown
what disease can occur if the basal nuclei breakdown?
parkinsons
what are the features of the diencephalon?
- Thalamus
- hypothalamus
- epithalamus
what is the feature of the thalamus?
- 80%
- many groups of nuclei that relay different types of sensory information to the cortex
- motor and limbic connections to the cortex
what is the function of the hypothalamus?
- homeostatis
- autonomic actions
- emotions
- body temperature
- food intake and thirst
- sleep-wake cycles
- hormone control
- major part of the endocrine system
what gland does the hypothalamus work with to control hormones and work within the endocrine system?
pituitary gland
what is the function of the epithalamus?
- control of melatonin
- day/night cycles
what gland does the epithalamus work with?
- pineal gland
- posterior commisure
what are the 4 features of the brain stem?
- midbrain
- pons
- medulla oblongatta
- cerebellum aka little brain
what is the function of the midbrain?
- visual and auditory informtaion
- reflexes associated with sight and sound
what is the function of the pons?
respiration
what is the directionality of the pons neurons?
ascending and decending, as well as transverse to link the cerebellum
where is the medulla oblongatta?
- most inferior
- joins spinal cord with brain at foramen magnum (hole in skull)
what is the function of the medulla oblongatta?
- autonomic reflex centre e.g. hiccups, breathing, heart rate etc.
what are the features of the cerebellum
- “little brain”
- second largest brain structure
- folds are call folia
- connects hemispheres by the vermis
- connects brain stem via the cerebellar peduncles
what is the function of the cerebellum?
- equillibrium
- balance and coordinations of movement
- uses the inner ear for information as well
where is the spinal cord?
- connected to the medulla oblongatta
- enclosed in the vertebral column
- about 42cm long
what is the function of the spinal cord?
2 way communication to and from the brain and body
where do reflex reactions go?
they are initiated and completed in the spinal cord, not to the brain but ends at the conus medullaris (L1/L2: about belly button height)
what are the features of the spinal cord?
- Conus medularis
- cauda equina
- fillum terminal
which parts of the spinal cord anchors it to the skeleton?
- fillum terminal
- cauda equina
what is the job of the dorsal root?
- receives information (afferent)
- sensory, touch etc
- if required sends information to brain
what is the job of the ventral root?
- reads information and reacts (efferent)
- motor signals, has myelinated and unmyelinated fibers
what are the 3 levels of protection for the CNS?
- meninges
- blood brain barrier
- cerebrospinal fluid
what are the 3 major types of meninges?
- dura mater (superficial)
- arachnoid mater (middle)
- pia mater (innermost)
what are the features of the dura mater?
- double layered, outer layer fused to periosteum
- dual venous sinuses between 2 layers (collect venous (deox) blood to go back to body)
- is a part of the dural folds (septa)
what are the features of the arachnoid mater?
- cobweb like in form (trabeculae)
- attached to the pia
- provides cushioning
- filled with cerebrospinal fluid (CSF) in the subarachnoid space
what are the features of the pia mater?
- follows the contours of the brain
- has lots of blood vessels to provide nutrients to the brain
- takes away harmful chemicals
where else are the 3 meninges found?
around the spinal cord
what is the blood brain barrier?
- blood vessels cover the brain and act as a gateway.
- lining of blood vessels is called endothelial cells
- endothelial cells are very closely connected to cell junctions
what does the cerebrospinal fluid (CSF) do?
- acts as an airbag for the brain and spinal cord against physical and chemical injury
- carried oxygen, glucose and other important substances from blood to nervous tissue
- moves around via the ventricles
how many ventricles does the CSF have?
- lateral ventricle x2
- third ventricle
- fourth ventricle