1 CNS(central nerve system)
- Brain
- Spinal cord
2. PNS(peripheral nerve system)
- Spinal nerve
- Cranial nerve
- All other nerves except CNS
- Frontal(Motor)
→ Broca area(frontal) : motor speech area, if this area damaged : Broca’s aphasia(kow what they wish to say but unable to speak words)
- Parietal(Sensory)
- Temporal(Auditory)
→ Wernicke’s area(temporal and parietal) : speech comprehension, if damaged: Wernicke’s aphasia(speak fluently, but nonsense speech, don’t understand words)
- Occipital(vision)
- Limbic system : emotional brain
2) Diencephalon
- Thalamus
- Hypothalamus : regulates homeostasis, secret hormones
- Epithalamus
- Subtalamus
3) Brain stem
- Midbrain(substantia nigra)
- Pons : control intensity of breathing
- Medulla oblongata: control breathing and heart rate
4) Cerebellum ; Maintain balance and posture, coordinating muscle movement
2. Spinal cord
- Dorsal horn : sensory neurons, Afferent neurons
- Ventral horn : Motor neurons, Efferent neurons
- Spinal nerve (8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccyx)
- Plexus
- Cervical plexus
- Brachial plexus
- Lumbar plexus
- Sacral plexus
Cervical plexus(C1 to C4)
C4 :Phrenic nerve → control diaphrgam
Brachial plexus
- CN I (Olfactory nerve / sense) : smell
- CN II (Optic nerve / sense ) : vision
- CN III ( Oculomotor nerve / motor)
- Motor : Eye movement :controls all muscles of the eye except for the superior oblique muscle controlled by the trochlear nerve
- Pupil light response- constrict pupil
- CN IV (Trochlear nerve / motor) : Eye movement superior oblique
- CN V ( Trigeminal nerve / sensory and motor )
- Sensory : skin of the face
- Motor : chewing
- pupil dilatation
6. CN VI ( Abducens nerve / motor ) : Eye movement lateral rectus
7. CN VII ( Facial nerve / sensory and motor)
- Sensory : sense of the taste for most tongue(⅔)
- Motor : facial expression, eyelid closing
- Lacrimation, salvation
8. CN VIII ( Vestibulocochlear nerve / sensory ) ; hearing and balance
9. CN IX ( Glosspharyngeal nerve / sensory and motor)
- Sensory : oral sensation, taste of the back part of the tongue
- Motor : swallowing
- Salivation, gag reflex
10. CN X (Vagus nerve / sensory and motor)
- Swallowing, gag reflex, coughing, heart rate, peristalsis, sweating (Provide sensory and Parasympathetic supply to structure in the neck and most organs in the chest and abdomen)
11. CN XI ( Accessory nerve / motor) : controls the neck muscles
12. CN XII ( Hypoglossal nerve / motor ) :controls tongue movement
- Pure motor : oculomotor, trochlear, abducent, accessory, hypoglossal
- Pure sense : olfactory, optic, vestibulocochlear
- Mixed : trigeminal, facial, glossopharyngeal, vagus
- Parasympathetic : oculomotor, facial, grossopharyngeal, vagus
- Somatic nerve system
- Autonomic nerve system
Somatic nerve system
- somatic nervous system allows you to move and control muscles throughout your body.
- The somatic nervous system consists of nerves that go to the skin and muscles and is involved in conscious activities.
- voluntary movement
- Somatic sensory fibers = afferent
- Motor nerve fibers = efferent
Autonomic system
- The autonomic nervous system consists of nerves that connect the CNS to the visceral organs such as the heart, stomach, and intestines. It mediates unconscious activities.
- Involuntary movement
- Sympathetic : fight or flight
- Parasymphatetic : relax and digest
Sensory Receptors
Muscle spindles and Golgi tendon Organ
Nerve fibers – Classification : image
- A type
- Alpha
- Efferent(somatic motor) : skeleton muscle
- Afferent(proprioceptor) : Ia(muscle spindle), Ib(golgi tendon organ)
- Beta
- Mechenoafferent of skin(fine touch, pressure, vibration)
- Type II afferent fibers( muscle spindle)
- Gamma
- Efferets : Muscle spindle
- Delta
- Afferent : Type III, fast(sharp) pain and temperature(cold)
2. B type : preganglionic sympathetic(autonomic nervous system)
3. C type
- Dorsal root : t(afferent, type IV) : slow pain, temperature(hot)
- Sympathetic : postganglionic