524- Nervous B CNS Flashcards
What nervous system organs fit into the CNS and PNS?
⭐CNS: Spinal cord
: Brain
⭐PNS: Nerves
: Ganglia
: Receptors
Functions of the CNS?
- integrate sensory information from receptors
- coordinate activity of effectors (conscious or unconscious)
Functions of the PNS?
DETECT STIMULI and TRANSMIT action potentials between receptors, CNS and effectors.
> Difference between grey and white matter
> What cells form the myelin sheath?
⭐ GREY (unmyelinated)
⭐ WHITE (myelinated axons).
myelin sheath formed by oligodendrocytes in CNS
Schwann cells in PNS
What do you call the collections of neuron cell bodies and bundle axons in:
> CNS
PNS
⭐CNS: Nucleus, Tract
⭐PNS: Ganglion, Nerve
Responsibilities of Brain and Spinal Cord?
⭐ Brain:
- manage sensory info + give orders
- thinking, feeling, remembering
⭐Spine:
- directs 2 way signals between brain and the rest of the body
- control basic muscle REFLEX that doesn’t need the brain to work.
What are the 3 folds found in the brain called and for?
⭐ Gyri - (ridges/little creases) (gyrus=1)
⭐ Sulci - (shallower grooves) (sulcus=1)
⭐ Fissures - (deep grooves)
used as landmarks to identify parts of the brain.
Why was the folds in the brain formed?
We need lots of synapses to be able to manage higher processes, which needs LOTS of nervous tissue. As the cerebrum grew through evolution to increase the surface area to hold these synapses, the skulls stayed the same, causing it to wrinkle and form these grooves to fit in.
How are parts of the brain kept separate? (4)
⭐ transverse cerebral fissure : cerebrum/cerebellum
⭐ longitudinal fissure: L/R cerebral hemispheres
⭐lateral sulcus : parietal/temporal, temporal/frontal
⭐ central sulcus: frontal/parietal
> Location and function of white matter.
> What is corpus callosum?
> INSIDE cerebral cortex
- they are tracts and fibers that transmit info between different parts of the brain.
⭐ thick band of white matter that allows communication between L & R hemispheres. They are formed by commissural fibers.
What are the 3 fibres in the brain? (function)
connects:
⭐ Association fibres- parts in SAME hemisphere
⭐ Commissural fibres- similar areas in L & R cerebral hemisphere.
⭐ Projection fibres- cerebral cortex to lower parts of the brain
What is the cerebral cortex? (made up of, what happens here?)
⭐ made up of wrinkled outer layer of grey matter
(where ALL CONSCIOUS processes occur)
- think, sense, feel, conscious control of mvmnt, facial expressions
⭐ and inner, squishy layer of white matter beneath it.
Function of frontal lobe + what it cortex(s) forms it
“control of movement (motor skills) and memory”
⭐ Primary cortex -controls all skeletal muscles + facial expressions. in front of central sulcus
⭐Premotor cortex- planning of movement. sends instructions to primary cortex (to do it correctly)
⭐Broca’s Area- controls speech (mouth and larynx to make sound) + planning of speech
⭐Prefrontal cortex- concentration, impulse control, THINKING (solve problems)
Functions of the Parietal lobe + what cortex (s) forms it
“sense of touch” (pain & pressure)
⭐Primary somatosensory cortex
- gets and interprets type & intensity of sensory input received by brain and proprioceptors (position receptors) + nociceptors (pain receptors) + mechanoreceptors (pressure, touch, vibration) from the skin
⭐Somatosensory association cortex
- using emotion and memory it adds meaning to sensory info
Functions of the occipital lobe + cortex (s) forming it
“vision”
⭐Primary visual cortex- gets visual info from retinas
⭐Visual association area- using memory and emotions it adds meaning to the visual information
Functions of the temporal lobe + cortex (s) forming it
“hearing”
⭐Primary auditory cortex
- gets sensory (hearing) info from inner ear (like pitch, loudness, location)
⭐Auditory association area
- using memory and emotion, adds meaning to sensory (hearing) to what’s been heard
⭐Wernicke’s Area
- for understanding language and speech (both written and spoken)
⭐Olfactory Cortex
- receives olfactory (smell) info from nasal cavity
- awareness of odors
: Olfactory bulb and tract send info from nasal cavity to brain about what you’ve smelt.
Functions of the insula + cortex (s) forming it
“sense of taste”
⭐Gustatory cortex
- gets and interprets taste stimuli from mouth
Function (2) and location of basal ganglia (what is it)
“collections of grey matter”
⭐deep within white matter, lateral to thalamus
⭐role is to act as relay stations between the cerebral cortex, cerebellum and brainstem
- start, stop and the control of movement
Functions and location of diencephalon (what are the 3 things making it up)
[deep inside cerebral hemispheres and superior to brainstem]
> Thalamus: sensory relay station, directs all sensory info (except smell) through the thalamus to the correct parts of the cortex.
> Epithalamus: secretes melatonin which help regulate the sleep-wake cycle
> Hypothalamus
What are the roles of the hypothalamus? (7)
1) autonomic control centre
2) emotional response centre
3) body temp regulation
4) regulation of food intake
5) regulation of water balance
6) regulation of sleep-wake cycle
7) control of hormone secretion
What is the brainstem? (function, location)
“conduction pathway for neurons, carrying info between upper and lower areas of the nervous system”
- superior to inferior:
⭐Midbrain
⭐Pons
⭐Medulla oblongata
Functions of the midbrain (3), pons (1) and medulla oblongata (4)
⭐Midbrain
: Visual reflex- head & eye tracking
: startle reflex - turn head toward unexpected sound
: part of conducting auditory signals (inner ear-> auditory cortex)⭐Pons
: control of RR and rhythm⭐Medulla oblongata
: control RR and rhythm
: regulation of BP (blood vessel diameter altered)
: HR and force of contraction
: reflexes like vomiting, hiccupping, swallowing, sneezing
What is the reticular formation? (location, function)
“clusters of grey matter running throughout the entire brainstem”
⭐regulates and maintains levels of consciousness and alertness.
(when asleep, it can prompt a response towards sensations)
What is the cerebellum? (location, function)
smaller part of the brain, inferior to the cerebellum containing both grey and white matter and also has 2 hemispheres. It has more neurons than the cerebrum.
⭐maintain balance
- involved in controlling planning, timing, and coordination of movements (like learning motor skills e.g., riding a bike)
