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207 Cards in this Set
- Front
- Back
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Describe the anatomy of the spinal cord with respect to the bones.
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Formed by 33 bones called vertebrae. -7 cervical -12 thoracic -5 lumbar -5 sacral -3 to 5 small coccygeal vertebrae |
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Describe the anatomy of the spinal cord with respect to the meninges
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the spinal cord is covered by three layers of connective tissue called meninges. -pia mater is the innermost layer attached to the outside of the spinal cord. -arachnoid is outside the pia mater and formed by delicate connective tissue that is connected to the pia mater by tiny filaments -subarachnoid space is found between the arachnoid and the pia mater and contains CSF -Dura mater is the outermost layer. It is a sturdy layer of connective tissue that is richly supplied with sensory nerve endings. |
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Describe the anatomy of the spinal cord with respect to the paired spinal nerves.
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30 pairs of spinal nerves that can be grouped into four regions that pass through the intervertebral foramen -8 spinal cord segments in the cervical region -12 segments in the thoracic region -5 segments in the lumbar region -5 segments in the sacral region |
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Describe the anatomy of the spinal cord with respect to the cauda equina.
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Nerve roots of the lumbar and sacral spinal that run inferiorly inside the spinal cord for up to 6 inches
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Describe the grey matter of the spinal cord. (be able to identify on a diagram) |
-the central core -neuron cell bodies and dendrites -organized into three regions; dorsal, lateral, and ventral horn |
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Describe the white matter of the spinal cord. (be able to identify on a diagram) |
-surrounds the grey matter core -contains axons -axons run up and down the spinal cord, connecting the body with the brain -may contain ascending tracts or descending tracts |
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Describe the dorsal horn of the spinal cord. (be able to identify on a diagram) |
-contains sensory (afferent) nerve fibers
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Describe the lateral horn of the spinal cord
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-contains the cell bodies of autonomic neurons (sympathetics and parasympathetics)
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Describe the ventral horn of the spinal cord
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-contains the cell bodies of motor neurons that innervate skeletal muscle (efferent) -lower motor neurons |
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Describe ascending tracts
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carry action potentials up to the brain -dorsal columns -lateral spinothalamic -anterior spinothalamic -spinocerebellar |
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Describe the function of the ascending tract: Dorsal Columns
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-located in the posterior (dorsal) white matter -convey sensations of conscious proprioception, vibration, and two-point discriminative touch to the brain -information comes from receptors in the skin, muscle, tendons, and joints -conveyed to the primary sensory cortex where awareness of sensation takes place, including knowledge of its specific location on the body, its duration, and its intensity |
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Describe the effect of a lesion to the ascending tract: dorsal columns
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-ipsilateral loss of two-point discrimination, vibration, and conscious proprioception
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Describe the function of the ascending tract: lateral spinalthalamic
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-located in the lateral white matter -carries nerve fibers that convey pain and temperature. -comes from receptors located in the skin and subcutaneous tissue -sensations perceived in the primary sensory cortex where perception and localization of the stimulus occur |
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Describe the effect a lesion has to the ascending tract: lateral spinalthalamic
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contralateral loss of pain and temperature
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Describe the function of the ascending tract: anterior spinothalamic
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-contains axons that convey the sensations of pressure, texture, and light touch -located in the anterior white matter -receptors located in the skin and subcutaneous tissue -perceived in the primary sensory cortex where perception and localization of the stimulus occur |
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describe the effect of a lesion of the ascending tract: anterior spinothalamic
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-contralateral loss of pressure and touch
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Describe the function of the ascending tract: spinocerebellar
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-conveys unconscious proprioceptive information to the cerebellum from muscles and tendons -monitor the activity of motor neurons |
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Describe the effect of a lesion on the ascending tract: spinocerebellar
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partial loss of unconscious proprioception
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Describe descending tracts
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-convey signals down from the brain to the body -connects the brain to lower motor neurons -responsible for controlling voluntary muscle contraction and movement -includes: lateral corticospinal, anterior corticospinal, reticulospinal, vestibulospinal |
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Describe the function of the descending tract: lateral corticospinal
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-located in the lateral white matter -responsible for control of voluntary movement |
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Describe the effect of a lesion on the descending tracat: lateral corticospinal
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-ipsilateral spastic paralysis
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Describe the function of the descending tract: anterior corticospinal tract
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-formed by a small number of corticospinal tract fibers that do not cross in the medulla oblongata -innervate lower motor neurons supplying upper extremity muscles -located in the anterior white matter |
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Describe the effect a lesion has on the descending tract: anterior corticospinal
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-ipsilateral spastic paresis |
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Describe the function of the descending tract: reticulospinal
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-originate in the brainstem reticular formation -control rhythmic gait patterns and muscle tone -contain the central autonomic fibers that control the autonomic nervous system |
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Describe the effect a lesion has on the descending tract: reticulospinal
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-loss of control, limb flexors -hypertonicity and muscle spasms |
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Describe the function of the descending tract: vestibulospinal
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-begin in the brainstem vestibular nuclei and descend through the brainstem and spinal cord -connect to interneurons and lower motor neurons -controls proximal limb muscles responsible for maintaining balance and posture -receive input from the inner ear, cerebellum, and other motor areas of the brain |
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Describe the effect a lesion has on the descending tract: vestibulospinal
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loss of control, postural muscles
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Describe how to perform a Babinski Test on a patient
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Beginning at the heel and progressing up the outside of the foot you then cross toward the base of the big toe
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What constitutes a negative response in the Babinski Test?
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Flexion of all five toes
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What constitutes a positive response in the Babinski Test?
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Extension of the big toe
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What does a positive Babinski Sign indicate?
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Suffering from CNS damage -indicates upper motor neuron damage |
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Where does the spinal cord receive blood from?
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-three arteries that run vertically along its length -an anterior spinal artery -two posterior spinal arteries |
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How can the spinal cord be injured?
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-from motor vehicle accidents -falls -sports injuries -violence -diseases -fractured of dislocated -traumatic bending -crushed |
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How is a spinal cord injury classified?
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-according to the segmental level of injury -by the level of intact function -by the number of limbs affected -complete or incomplete |
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Define quadriplegia
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complete or partial paralysis of all four limbs
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Define paraplegia
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paralysis of the lower extremities only
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Define hemiplegia
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paralysis of one side of the body
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Define monoplegia
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paralysis of one limb
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Define incomplete spinal cord lesion
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spinal cord injuries where any motor function or sensation remains
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Define complete spinal cord lesion
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complete paralysis and a complete loss of sensation below the level of the injury
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Define spinal shock
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the first several weeks after spinal cord injury -no sensation or movement below the injured spinal cord segment |
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Define clonus
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a series of rapid, rhythmic alternating movement
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Describe the complications that can manifest post a spinal cord injury
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-pressure sores -heterotopic ossifications -autonomic dysreflexia -spasticity -bladder and bowel control -sexual functioning |
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Explain autonomic dysreflexia
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-a potentially life-threatening condition that can occur in people with spinal cord injuries about the T5 level -from a noxious stimulus that sends pain signals toward the brain however the signal cannot reach the brain because of the spinal cord injury -Pain signals communicate with the sympathetic nervous system to produce uncontrolled sympathetic response involving vasoconstriction and continually increasing blood pressure along with decreased heart rate. |
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Describe the symptoms of autonomic dysreflexia
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-pounding headache -sudden increase in blood pressure -sweating -goose-bumps above injury level -very flushed face |
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Describe the area of spinal cord injury with respect to Brown-Sequard syndrome
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a lesion affecting exactly one-half (right or left) of the spinal cord
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Describe the area of spinal cord injury with respect to Central Cord syndrome
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caused by damage to the center of the spinal cord
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Describe the area of spinal cord injury with respect to Anterior Cord syndrome
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results from damage to the anterior part of the spinal cord that spares the posterior white matter
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Describe the area of spinal cord injury with respect to Cauda Equina syndrome
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injury to the dorsal and ventral nerve roots in the cauda equina that results in loss of sensation, flaccid paralysis, and loss of sympathetic and parasympathetic responses in the pelvis
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Explain the difference between a spastic neurogenic bladder and a flaccid neurogenic bladder
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-spastic neurogenic bladder: Voluntary sphincter is lost because patients are unaware of fullness and because control of voluntary sphincter muscles is lost -Flaccid neurogenic bladder: patients are not aware that the bladder is full and cannot voluntarily inhibit or initiate bladder emptying |
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Describe the composition of peripheral nerves
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Peripheral nerves are made up of axons -both motor and sensory -also somatosensory neurons |
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Describe the function of Motor axons
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-leave the central nervous system via ventral roots -innervate skeletal muscle -lower motor neurons |
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Describe the function of sensory axons
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-carries sensation from the skin, subcutaneous tissue, muscle, bone, ligaments, and joints -transmit sensations such as pain, temperature, touch, vibration, and proprioception |
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Describe the function of autonomic fibers
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-all 30 pairs of spinal nerves contain sympathetic autonomic neruons -innervate smooth muscle located in the blood vessel walls and sweat glands |
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Describe the dorsal ramus
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-curves toward the back -innervates muscle, skin and other structures of the back |
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Describe the ventral ramus
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-curves anteriorly -supplies structures of the anterior and lateral body regions as well as the upper and lower extremities |
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How many segments are in the spinal cord?
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-30 individual spinal cord segments -each gives rise to a pair of spinal nerves |
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Describe the formation of a plexus
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where spinal nerves interweave to form a nerve networkd -there are four major plexuses |
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What are the four major plexuses?
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-cervical -brachial -lumbar -sacral |
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Describe the Cervical Plexus spinal nerve composition
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-consists of axons from spinal nerves C1-C5
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What does the Cervical Plexus innervate?
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-structures in the neck -small muscles involved with swallowing and speech -innervate the thoracoabdominal diaphram |
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What are the two largest cervical plexus nerves?
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-Ansa Cervicalis nerve -Phrenic nerve |
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Describe the Phrenic nerve
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-travels down through the neck and thorax -innervates the thoracoabdominal diaphram -contains nerve fibers from C3-C5 |
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Describe what happens if the Cervical Plexus was injured
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-if injured above C3 the diaphragm will be paralyzed and respiration will stop
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What are hiccups
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-spasms of the diaphragm
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Describe the Brachial Plexus spinal nerve composition
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-spinal nerves C5-T1 -located in the lower part of the neck and passes through the armpit (axillary region) |
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What does the Brachial Plexus innervate
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-muscles of the upper extremity
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How is the Brachial Plexus organized? |
-into five separate regions
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What are the five separate regions of the Brachial Plexus?
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-Roots -Trunks -Divisions -Cords -Branches |
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What makes up the ROOTS in the Brachial Plexus
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the five ventral rami -C5 -C6 -C7 -C8 -T1 -each root combines into a trunk |
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What makes up the TRUNKS in the Brachial Plexus
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-Upper trunk: C5 and C6 combined -Middle trunk: C7 -Lower trunk: C8 and T1 combined -each trunk splits into two divisions |
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What makes up the DIVISIONS of the Brachial Plexus
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-Anterior -Posterior -both pass behind the clavicle and give rise to the brachial plexus cords |
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Describe the ANTERIOR DIVISION of the brachial plexus |
forms nerves the innervate muscles and skin found in the anterior aspect of the upper extremities
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Describe the POSTERIOR DIVISION of the brachial plexus
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forms nerves that supply posterior structures
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Describe the CORDS of the brachial plexus
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-Lateral cord: formed by nerve fibers form the upper and middle trunks -Medial cord: composed of neurons derived from the lower trunk -Posterior cord: contains nerve fibers from all three trunks -in the axilla (armpit) gives rise to five major branches (named nerves) |
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Describe the BRANCHES of the brachial plexus
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-five major branches or named nerves -supply most of the muscles and all of the sensation of the upper limb |
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Name the five major nerves (branches) of the brachial plexus
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-three large anterior division branches: *musculocutaneous *median *ulnar -two large nerves from the posterior cord: *axillary *radial |
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Describe the MUSCULOCUTANEOUS nerve
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-comprised of C5, C6, and C7 -supplies motor innervation to the anterior arm muscles (biceps brachii, coracobrachialis, and brachialis) |
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Describe the MEDIAN nerve
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-comprised of C6-T1 -innervates muscles located in the anterior compartment of the forearm and supplies muscles of the thumb and sensory innervation to the lateral part of the hand |
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Describe the ULNAR nerve
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-comprised of C8 and T1 -innervates muscles of the ulnar aspect of the forearm and most of the intrinsic hand muscles -provided sensation to the medial third of the hand |
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Describe the AXILLARY nerve
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-comprised of C5 and C6 -innervates the shoulder (deltoid and teres minor) |
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Describe the RADIAL nerve
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-comprised of C6-T1 -innervates all posterior muscles of the arm and forearm -sensory innervation of parts of the posterior arm, forearm, and hand |
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Describe the path of a thoracic spinal nerve
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-do not form plexus -divide into dorsal and ventral rami -ventral rami runs laterally beneath the ribs to form intercostal nerves |
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What does the DORSAL RAMI of the thorax spinal nerve innervate?
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-structures on the back, including the intrinsic back muscles and overlying skin
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What does the VENTRAL RAMI of the thorax spinal nerve innervate?
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-supply intercostal muscles and skin of the thoracic region
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Name the virus that causes shingles
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-Herpes Zoster
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What is the childhood disease associated with the virus Herpes Zoster?
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-chicken pox
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What is the spinal nerve composition of the LUMBARSACRAL PLEXUS?
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-comprised of L1-S4
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Describe the Lumbar Plexus
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-compose of nerve fibers from spinal segments L1-L4 -two major nerves: *obturator nerve *femoral nerve |
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Describe the OBTURATOR NERVE of the Lumbar Plexus
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-comprised of L2-L4 -provides sensation to the medial thigh -provides motor function to the hip adductor muscles |
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Describe the FEMORAL NERVE of the Lumbar Plexus
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-comprised of L2-L4 -innervates structures in the anterior thigh and hip |
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Describe the Sacral Plexus
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-comprised of nerve fibers from L4-L5 and S1-S4 -Three major nerves: *Sciatic nerve *Tibial Nerve *Common Peroneal nerve |
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Describe the SCIATIC NERVE of the Sacral Plexus
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-comprised of L4-L5 and S1-S3 -Largest nerve in body -innervates the posterior thigh |
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Describe the TIBIAL NERVE of the Sacral Plexus
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-comprised of L4-L5 and S1-S3 -innervates the posterior and lateral leg |
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Describe the COMMON PERONEAL nerve of the Sacral Plexus
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-comprised of L4-L5 and S1-S2 -innervates the anterior and lateral aspect of the lower leg |
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Define Sciatica
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clinical condition that describes injury to inflammation of the sciatic nerve
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Describe how SCIATICA is associated with pirifomis syndrome
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the sciatic nerve is compressed by the pififormis muscle when it becomes inflamed or excessively tight. -causes radiating pain or numbness down the entire lower extremity |
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What are the layers covering each peripheral nerve?
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--epineurium --perineurium --endoneurium |
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Describe the EPINEURIUM
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-outermost covering -continuous with the dura mater around the spinal cord -dense, fibrous and tough |
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Describe the PERINEURIUM
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-internal to the epineurium -groups individual nerve fibers into bundles -helps create the blood-nerve barrier |
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Describe Fascicles
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-bundles of individual nerve fibers surrounded by perineurium
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Describe the ENDONEURIUM
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-innermost connective tissue sheath -wraps each individual nerve fiber (axon) with a coat of delicate, loose connective tissue |
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How can peripheral nerves be classified?
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-according to size (diameter) and the amount of myelin covering them -according to their conduction velocity |
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Define ALPHA MOTOR NEURON
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-innervate muscle to create muscle tension and produce movement -about 12 to 20 um in diameter -fast conducting and have thick myelin sheaths |
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Define GAMMA MOTOR NEURONS
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-innervate muscle spindles -involved in maintenance and alteration of muscle tone and do not produce movement - 6 to 12 um in diameter -slower conducting |
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How can a peripheral nerve be damaged?
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-trauma or disease -excessive stretching -compression -lacerations -infections (shingles & leprosy) -ischemia -metabolic conditions (diabetes mellitus) -autoimmune disorders (Guillain-Barre syndrome) |
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Describe what deficits may be observed if a peripheral nerve is damaged
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-damage to peripheral nerves causes neuropathy: impairment of both motor and sensory functions -sensation is decreased, lost or abnormal -Parethesia: abnormal sensation described as prickling, tingling, or pins-and-needles -glove and stocking sensory loss -weakness -paralysis -hypertonia -tendon reflexes are depressed/lost -loss of sweating -bowel and bladder incontinence -sexual impotence -blurred vision -dry eyes and mouth -vomiting |
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What does the autonomic system control>
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-cardiac muscle and smooth muscle throughout the body
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What are the sections of the autonomic system?
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-sympathetic -parasympathetic |
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What is the general function of the sympathetic system?
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-prepares the body to cope with emergency situations
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What is the general function of the parasympathetic system?
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-responsible for maintaining homeostasis
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What are the various functions of the sympathetic system?
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-regulation of blood flow by vasoconstriction and vasodilation -increase in systemic blood pressure -dilation of pupils -production of thick saliva -dilation of the trachea and bronchi -increase contraction strength and heart rate |
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Where are the sympathetic neurons have their cell bodies?
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-in the spinal cord at levels T1-L2
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Explain what the sympathetic chain ganglia is
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-20 to 25 linked sympathetic ganglia that lies along the posterior body wall
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What does the sympathetic axons innervate?
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-smooth muscle in the skin, subcutaneous tissues, and muscle
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What is released when there is sympathetic stimulation of the adrenal gland by splanchnic nerves?
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-adrenalin (epinephrine)
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What neurotransmitters are used in the sympathetic nervous system?
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-acetylcholine -norepinephrine |
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What are the synapses containing acetylcholine called?
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-cholinergic
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What are the synapses containing norepinephrine called?
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-adrenergic
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Where are cholinergic synapses found?
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-sweat glands all over the body -arterioles that supply skeletal muscle |
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What does stimulation of cholinergic synapses produce?
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-sweating -vasodilation of arterioles supplying skeletal muscle (increased blood flow) |
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Where are adrenergic synapses located?
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-walls of arterioles and small veins
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What does stimulation of adrenergic synapses produce?
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-vasoconstriction (increase blood pressure) -decrease saliva production -dilates pupil -tightens sphincters (slowing passage of food in digestive tract) |
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What is the function of acetylcholine?
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-vasodilation and increased blood flow to skeletal muscle -sweating and cooling of the body |
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What is the function of norepinephrine?
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-general vasoconstriction and increased systemic blood pressure -increased heart rate and contraction strength -relaxation of airways -decreased digestion and urinary function |
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What does the parasympathetic system innervate?
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-internal organs
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Where does the parasympathetic neurons have their cell bodies?
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-in the brainstem and the sacral spinal cord
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What does the parasympathetic axons regulate?
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-digestion -reproduction -urinary function -heart rate -bronchial diameter |
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What are the various functions of the parasympathetic nervous system?
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-pupillary constriction -lens shape -secretion of tears and saliva -slow the heartbeat -decrease heart contraction strength -constrict trachea and bronchi -stimulate activity of liver, gallbladder, and pancrease -stimulate bladder emptying |
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What neurotransmitter does the parasympathetic system release?
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-Acetycholine
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What is the control center in the brain for autonomic regulation?
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-hypothalamus
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What is the relationship between the autonomic nervous system and the limbic system?
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-connection between emotional states and bodily responses -ex: blush when embarrassed |
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Explain the impact on function to the ANS when there is a spinal cord injury above T4
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-most of the ANS is disconnected from its hypothalamic control center -cannot sweat in response to heat -unable to regulate blood pressure - lose control of sacral parasympathetics |
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What is autonomic dysreflexia?
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-painful stimulus that the patient is unaware of
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What is the connection between the ANS and autonomic dysreflexia?
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-autonomic dysreflexia causes are large sympathetic response -constriction of arteries -piloerection -increased heart contractility -increased heart rate |
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What is Complex Regional Pain Syndrome?
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-abnormal response of the sympathetic nervous system to injury
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What are the divisions of the sensory system?
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-somatosensory (general) -special sensory |
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Where are the sensations for somatosensory located?
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-skin -subcutaneous tissue -muscle -tendons -bones -joints |
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What are the somatosensory sensations?
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-pain -temperature -pressure -touch -vibration -position sense (proprioception) |
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Define sensory receptors
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-tiny receptors located all over the body that convert stimuli into action potentials (nerve impulses)
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What does the receptor Pacinian Corpuscles detect?
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-vibration and deep pressure
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What does the receptor Meissner's Corpuscles detect?
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-two point discriminative touch
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What does the receptor Merkel's Cells detect?
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-texture
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What does the receptor Hair Follicle Receptors detect?
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-light touch
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What does the receptor Ruffini Corpuscles detect?
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-stretching of the skin
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Define stereognosis
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ability to determine the identity or meaning of an object by touch
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What do thermal receptors detect?
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-changes in temperature
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what do nociceptors detect?
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-pain
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What stimuli doe nociceptors respond to ?
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-stimuli that either do damage to tissue or that could damage tissue
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What are the types of nociceptors?
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-mechanical nociceptor -thermal hot nociceptor -thermal cold nociceptor -polymodal pain receptor |
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What do proprioceptors detect?
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-body position and movement -muscle length, muscle tension, position and movement of joints |
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What are muscle spindles?
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-stretch receptors that detect changes in muscle length
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Explain Gamma Motor Neurons
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-synapse onto spindle muscle fibers -control how sensitive the muscle spindles are to muscle stretch -controlled by motor centers in the spinal cord and brain |
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What do Golgi Tendon Organs detect?
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-muscle and tendon tension
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What do Joint Receptors detect?
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-joint position, movement, pain and inflammation within the joint
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What is the purpose of pain?
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-motivates us to avoid harmful stimuli
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What can cause pain?
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-when cells are injured or when a stimulus is strong enough to potentially damage cells -mechanical stimuli (crushing, pinching) -chemicals (acid) -temperature extremes -ischemia (lack of blood flow) |
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Describe Acute Pain
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-results from direct injury to tissue and from the resulting inflammation -short duration, lasting until injury is healed -protective purpose |
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Describe Long-Term Pain
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-can be classified as either nociceptive or neuropathic pain
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Define Nociceptive pain
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-caused by a long-lasting stimulus that activates nociceptors
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Define Neuropathic pain
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-from direct injury to peripheral nerve fibers
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Describe Chronic pain
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-persists even when the initial injury has healed -pain occurs b/c injured axons become overexcited and generate action potentials spontaneously |
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What sensations are included in special sensory
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-vision -hearing -balance -taste -smell |
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Explain the physical mechanisms of sight
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-visual receptors convert light into action potentials that are transmitted from the eyes to the rain, where we perceive and interpret the world
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Where are the visual receptors located?
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-retina
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What happens when light strikes the retina?
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-photoreceptors convert the light into action potentials
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What are the types of photoreceptors?
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-rod -cones |
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Describe the photoreceptor Rods
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-125 million rods -all over the retina -work in dim light -responsible for black and white vision |
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Describe the photoreceptor Cones
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-7 million cones -concentrated inn the middle of the retina (macula) -important for clear, sharp vision perception -need bright light to work -responsible for color vision -3 kinds of cones (blue light, green light, red light) |
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Describe Color Blindness
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-person is missing one or more of the three types of cones (blue, green, red light)
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Explain Cataract
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-eye becomes cloudy and impacts both clarity and color
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Explain the Optic Nerve
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-Cranial nerve II -Each eyeball is connected to -contains 1 million neurons -runs from the back of eyeball into the skull through the optic canal |
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Explain Detached Retina
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occurs when the retina comes loose and pulls away from the back of the eyeball
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Explain Macular Degeneration
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causes death of photoreceptors in the macula and can cause decreased vision or blindness
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Explain Retinopathy of Prematurity
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results from supplemental oxygen given to babies born too early
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What is the Optic Chiasm
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-where the two optic nerves meet on the undersurface of the brain and form an "X"
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Explain the Primary Visual Cortex
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-when action potentials reach we are able to consciously perceive the visual information -visual perception takes place here |
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Explain Hemianopsia
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-damage to one optic tract or to the primary visual cortex on one side of the brain causes loss of vision in the opposite visual field
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Explain the auditory system
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-allows us to perceive sound, locate it in space, and to understand the meaning, important for understanding language
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What are the parts of the ear?
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-external -middle -inner |
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What does the external ear do?
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-collects sound waves and funnels them into the middle ear
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Explain the Ear Drum |
-thin sheet of tissue between the external and middle ear -vibrates and transmits the vibrations into the middle ear |
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Explain what happens in the middle ear
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-contains three tiny bones called auditory ossicles (the hammer, anvil, stirrup) -when eardrum vibrates the malleus (hammer) moves and transmits the vibration to the anvil (incus) and sends it to the stirrup (stapes). -transmits the vibration by sound waves into the inner ear |
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What are the two parts of the inner ear?
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-cochlea -vestibular apparatus |
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What is the Organ of Corti
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where the receptor cells responsible for hearing are -18,000 receptor cells called Hair Cells |
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Explain the Vestibulocochlear Nerve
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-cochlear hair cells in the inner ear form synapses with neurons in the cochlear part -VIII nerve |
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Explain the Primary Auditor Cortex
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-in the temporal lobe -where perception of sound takes place -important for locating sounds in space |
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What is the purpose of the vestibular system?
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-concerned with detecting the position and movement of the head -maintaining balance -works together with proprioceptors located in muscles, tendons, and joints |
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Where is the vestibular system located?
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-within the inner ear
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Explain the Vestibular Apparatus
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-located in the inner ear -detects liner and rotational movement of head -consists of two parts |
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What are the two parts of the vestibular apparatus?
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-otolithic organs (utricle and saccule) -semicircular canals |
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Explain Utricle
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-detects horizontal plane motion
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Explain Saccule
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-detects vertical (up and down) movement
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Explain Otoliths
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-small calcium carbonate crystals |
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Explain Semicircular Canals
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-three pairs of semicircular canals -each pair is responsible for detecting a different direction of head movement |
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Explain Vertigo
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a sensation of extreme dizziness
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Explain Meniere's Disease
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condition in which excess endolymph causes swelling inside the vestibular apparatus and cochlea
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Explain BPPV
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-benign paroxysmal positional vertigo -episodes of dizziness or vertigo that lasts from 5 to 30 seconds -rapid change in head movement -caused by otoconia that have come dislodged from the utricle and fall into the posterior semicircular canal |
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Explain Dix-Hallpike Test
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-involves moving a person from sitting to supine while rotating and extending the head -conformation test for BPPV |
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Explain Nystagmus
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-clinical sign of vertigo -jumping of the eyes |
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Explain Eply Maneuvers
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-treatments involve a sequence of head movements that help to re-position the dislodged otoconia back into the utricle
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What sources in the body contribute to a persons sense of balance?
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-inner ear vestibular apparatus -the visual system -peripheral structures including muscles, tendons, and joints |
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What is the interrelationship between the sensation of smell and taste?
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-essential for making sure that we do not eat spoiled food and that we avoid substances that can be harmful -provide a rich sensory experience -a great deal of flavor of food is by its smell |
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Explain the Primary Olfactory Cortex
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-in the temporal lobe -for conscious awareness of the odor |
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Explain Anosmia
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-loss of ones sense of smell
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Where are taste receptors located?
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-on the tongue
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What are the types of taste receptors?
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-salty -sweet -sour -bitter -umami |
