13.1 Peripheral nervous MEMORIZE SLIDES 54, 55, 75 Flashcards
Special somatic senses
Hearing
Balance/equilibrium
Vision
Special visceral senses
Chemical:
Gustation
Olfaction
Visceral motor division
=Autonomic nervous system
Has parasympathetic and sympathetic
Somatic sensory
Special somatic senses:
hearing
balance
vision
Visceral sensory
Special visceral senses: chemical senses
Gustation
Olfaction
Sensory receptor according to location
Exteroreceptors
Near body surface
Stimulations outside of body
Sensory receptor according to location
Interoreceptors
Receive stimuli from internal viscera
Detect chemicals
Taste
Stretching of tissues
Temperature
Sensory receptor according to location
Proprioceptors
Located in skeletal muscles, tendons, joints, ligaments
Detect degree of stretch
Sensory receptor according to stimulus
Mechanoreceptors
Respond to touch, stretch, vibration, itch
Baroreceptors monitor blood pressure
Sensory receptor according to stimulus
Thermoreceptors
Respond to temperature changes
Capsaicin receptors
Menthol receptors
Sensory receptor according to stimulus
Chemoreceptors
Respond to chemicals in solution
Sensory receptor according to stimulus
Photoreceptors
In eyes
Sensory receptor according to stimulus
Nociopreceptors
Pain
Potentialy damaging stimuli
Sensory receptor according to structure
Uncapsulated with free nerve endings
Abundant in epithelia underlying connective tissue and other tissues
Respond to pain and temperature
MERKEL DISCS, epithelial tactile complexes: modified free nerve endings which consists of tactile epitheliel cell in basal layer of epidermis which is innervated by sensory nerve ending
Hair follicle receptors wrap around hair follicles
Sensory receptor according to structure
Encapsulated nerve endings
Capsule of connective tissue
Sensory receptor according to structure
Encapsulated nerve endings
Tactile (Meissner’s) copuscles
Dermal papillae for discriminative touch and low frequency vibration of fingetips, nipples, external genitalia
Sensory receptor according to structure
Encapsulated nerve endings
Lamellar (Pacinian) corpuscles
Hypodermis, dermis, tendons, ligaments, joint capsules, periostea for deep pressure, stretch and high frequency vibration
Sensory receptor according to structure Encapsulated nerve endings Bublbous corpuscles (Ruffini endings)
Deep dermis, hypodermis, joint capsules -> pressure and stretch
Sensory receptor according to structure
Encapsulated nerve endings
Proprioceptors
Monitor stretch of locomotor organs
Propioceptors
Muscle spindles
Measure changing length of muscle
Embeded in perimysium between fascicles
Modified skeletal muscles, intrafusal muscle fibers, innervated by sensory fibers
Propioceptors
Tendon organs
Monitor tension with tendons
Propioceptors
Joint kinesthetic receptors
Sensory nerve endings within joint capsules
Cranial neves
Pass through foramina of skull
Numbered I-X!!
Vagus nerve is only cranial nerve that extends to abdomen
Cranial nerve nuclei locations
Forebrain: I, II Midbrain: III, IV Pons: V, VI, VII Medulla: VIII, IX, X, XII Spinal cord: XI accessory nerves formed from ventral rootlets of spinal cord
Medulla
CN VIII
Vestibuloicochlear nerve
Associated brain nuclei are sensory vestibular nuclear complex and sensory cochlear nuclei
Medulla
CN IX
Glossopharyngeal nerve
Associated nuclei are nucleus ambiguus (motor) and solitary nucleus (sensory)
Medulla
CN X
Vagus nerve
Associated brain nuclei are dorsal motor nucleus of vagus, nucleus ambiguous and solitary nucleus (sensory)
Medulla
CN XII
Hypoglassal nerve
Associated brain nucleus is hypoglossal nucleus (motor)
Pons
CN V
Trigeminal nerve: trigeminal motor nucleus and trigeminal sensory nucleus
Pons
CN VI
Abducens nerve
Pons
CN VII
Facial nerve: facial nerve nucleus is motor and nervus intermedius is sensory
Midbrain
Periaqueductal gray matter
Most ventral part of periaqueductal gray matter contains motor neuron cell bodies to CN III (oculomotor) nuclei and CN IV (trochlear) nuclei
CN IV is only CN that emerges from dorsal bainstem; it emerges just caudal to inferior colliculus
Primarily or exclusively sensory nerves I, II, III
Special sensory fibers for smell (I), vision (II), and hearing and equilibrium (VIII)
Exclusively motor nerves: III, IV, VI, XI, XII
Contain somatic motor fibers for skeletal muscles of eye (III, IV, VI), neck (XI), and tongue (XII)
Mixed motor/sensory nerves
V: chewing muscles
VII: facial expression muscles
IX
X
CN I
Olfactory nerve
CN I is sensory nerve for smell that runs through cribiform plate of ethmoid bone
CN II
Optic nerve runs through optic canal of orbit
CN III
The oculomotor nerve innervates four of the extrinsic eye muscles: inferior oblique, superior rectus, inferior rectus & medial rectus
Runs through superior orbital fissure
CN IV
Trochlear nerve innervate superior oblique muscle (extrinsic eye muscle) runs through superior orbital fissure
CN V
Trigeminal nerves
Largest of cranial nerves
Chewing!
Opthalamic division V1: through superior orbital fissure
Maxiallary division V2: through foramen rotundum
Mandibular division V3: through formanen ovale
Cell bodies of sensory neurons located in trigeminal ganglion
Mandibular division contains motor fibers that innervate chewing
CN VI
Abducens nerves
Abducts the eyeball by innervation of lateral rectus muscle
runs through superior orbital fissure
CN VII
Facial nerves
facial expression
Enters temporal bone via inernal acoustic meatus
Chordi tympani branch (taste) runs through stylomastoid foramen
CN VIII
Vestibulocochlear nerves
Hearing balance
Passes through internal acoustic meatus and enters into inner ear of temporal bone
CN IX
Glossopharyngeal nerves
Innervates tongue and pharynx
Runs through jugular foramen
CN X
Vagus nerve Mixed sensory and motor nerve Through jugular formane Extends into thorax and abdomen Parasympathetic innervation of organs
CN XI
Accessory nerves
Fromed from ventral nerves are formed from ventral rootlets of spinal cord C1-C5 so has features of both cranial and spinal nerves
Does not arise from brain stem
Enters skull as accessory nerve through foramen magnum and exits through jugular formaen and innervate trapezius and sternocleidomastoid
CN XII
Innervates tongue muscles
Runs through hypoglossal canal
Inferior to tongue
