L7 - CNS Flashcards
Central nervous system contains
The brain and spinal cord
The CNS function is
Integration
What is gray matter made up of?
Cell bodies, dendrites, unmyelinated axons
What is white matter made up of?
Myelinated axons
In the spinal cord where is white matter found? Gray matter?
White matter = tracts
Gray matter = horns
In the brain where is gray matter and white matter found?
Grey matter = cerebral cortex & cerebral nuclei
White matter = tracts ( connect the brain together)
What are the functions of the spinal cord?
- Transmit sensory info to the brain ( ascending tracts)
- Transmit motor commands from brain (descending tracts)
- Integrate spinal reflexes ➡️ stretch reflex
Decussation can occur where
Decussation = Cross over
- can happen at the medualla obligata and spinal cord
What are the functions of the brain?
- Receive/ interpret sensory information
- Respond with motor output
- Perform higher brain functions
What Carries out brain functions
Interneurons and neurotransmitters
What causes complexity in the brain?
Wiring - interneuron to interneuron communication
Synapses - receptors + neurotransmitters
Organizing principles of the brain
- Redundancy
- different brain regions work together - Bilateral structural symmetry
- left and right look the same - Evolutionary organization
- areas nearest spinal cord = most primitive (survival)
Brain ventricles are defined as
Brain spaces with cerebral spinal fluid
What are the functions of cerebral spinal fluid?
- support/ protects brain/ spinal cord
- provides nutrition (derived from plasma)
- maintains ionic balance and cranial pressure
- removes wastes during sleep
True or false ; cerebralspinal fluid is constancy secreted/ reabsorbed at the same rate
True
Glymphatic system
CSF flushes cellular wastes from the brain during sleep
Explain how the glymphatic system works
- Brain shrinks creating space for csf flow
- Csf enters interstitial fluid outside of arteries
- Flushes waste in interstitial fluid to outside veins
- Wastes leave brain entering lymphatic system
Hydrocephalus
1. Cause
2. Treatment
Water in the brain - happens in babies
- Partial obstruction of normal Csf flow
- Insert a drain ➡️ shunt
What are the four regions of the brain?
- Cerebrum - outer part
- cerebral cortex & basal nuclei - Diencephalon
- thalamus & hypothalamus - Brain stem
- pons, medulla obligata, midbrain - ## Cerebellum
Corpus collosum
Connects left and right hemispheres
What are the 5 lobes of the brain?
Frontal, occipital, parietal, temporal, insula
Longitudinal fissure
Separates left and right hemispheres
Central sulcus
Separates frontal & parietal lobes
Right vs left brain functions
Left - language, analytic
Right - visual, spatial
The cerebrum contains….
Cerebral cortex, white matter, & basal nuclei
Corpus callosum
Myelinated axon fibers connecting left/ right hemispheres
Primary motor cortex location and function
In frontal lobe - pre central gyrus
Function = voluntary control of skeletal muscle
Somatosensory cortex location and function
Location= parietal lobe - precentral gyrus
Function = interpret general sensory input (skin, joints, muscles)
Frontal lobes functions
Personality/ behavior
- intellect/ higher thinking
- verbal communication
Parietal lobe functions
- understand speech
- Formulate words
Occipital lobe functions
Movement of eyes/ vision
Temporal lobe functions
Interpret auditory Input
Insula lobe functions
Integrate sensation (pain) w/ visceral response
Wenicke’s area function
Understands words
- language comprehension
What happens if the wenicke’s area is damaged?
Can’t understand words but can articulate
Broca’s areas function
Speaks words
- motor speech area
What happens if the Broca’s area is damaged?
Can understand words but can’t articulate
What is a PET scan? And how does it work?
Pet scan = imaging of brain activity by looking at the use of glucose used as energy
Basal nuclei function and location
Location: deep in cerebrum
Function: modify output of motor pathways (desending)
What is huntingtons disease?
Accumulation of protein ; damaging basal nuclei causing build up of Csf in ventricles
Midbrain
Subconscious control of skeletal muscle
What two nuclei are involved in the midbrain?
- Substantia nigra
- Red nucleus
Red nucleus
A change in motor coordination
Cerebellum
Smooth and coordinate skeletal muscle activity
- goal directed
- posture/ balance
- new movement activity’s program here
What controls skeletal muscle ( hint: 1 conscious 2 subconscious]
Conscious = primary motor cortex
Subconscious = basal nuclei, midbrain and cerebellum
Diencephalon
Contains thalamus and hypothalamus
Thalamus function
Sensory relay station
➡️send output to appropriate brain regions
- grey matter
Hypothalamus function
Maintain homeostasis & links nervous system to endocrine system
- grey matter
Brain stem
Oldest most primitive part of brain
Contains: pons & middle oblongata
Pons function
Respiratory control center
( regulates breathing)
- works with medulla
Medulla oblongata function
- Respiratory center
- Cardiac control center
- control heart rate - Vasometer center
- control blood vessel diameter
Lambic system
Basis of emotional states
- fear, aggression, sexual drive, feeding
Reticular activating system
Regulated sleep & wakefulness
Location of reticular activating system
Fibers from brain stem to thalamus and cerebral cortex
