40743827 Npte Neuroanatomy Lec 2

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    y NEUROANATOMY

    y METC

    y Major landmarks, first orientation

    y Major landmarks: The four lobes

    y Primary Areas

    y Divisions ofPrimary Motor and Somatic Areas

    y Parieto-occipital sulcus

    - Separates parietal from occipital lobe

    * Calcarine sulcus- surounded by visual receptive area

    y Blood supply

    y CIRCLE OF WILLIS

    y Formed by two internal carotid arteries and 2 vertebral arteries at the base of the brain

    y Functions of the Cortex

    Language

    1- Broca s Area

    an area of the frontal lobe, usually in the left hemisphere, that directs the muscle movements involved

    in speech

    2- Wernicke s Area

    a brain area involved in language comprehension and expression; usually in the left temporal lobe.

    y Specialization and Integration in Language

    1- Visual cortex receives written words as visual stimulation.

    2- Angular gyrus transforms visual representations into an auditory code.

    3- Wernicke s area interprets auditory code.

    4- Broca s area controls speech muscles via the motor cortex.

    5- Motor cortex word is pronounced.

    y Lateralization

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    Left Hemisphere

    Verbal competence

    Speaking, reading, thinking & reasoning

    Processes info in sequence

    One piece ofdataat a time

    logical

    Right Hemisphere

    Nonverbal areas

    Comprehension, spatial relationships,drawing, music, emotion

    Processes info. As awhole

    intuitive

    y Emotion and Lateralization

    Left Hemisphere

    y Important for the expression of positive emotion

    y Damage to the L.H. leads to loss of the capacity of joy.

    y Activation in the L.H. leads to tendencies to approach other people.

    Right Hemisphere

    y Important for the expression ofnegative emotion

    y Damage to the R.H. may make people euphoric.

    y Activation in the R.H. leads to tendencies to withdraw from people.

    y The Homunculus

    y Cerebral Cortex:

    Outer layer ofneurons (1mm thick)

    y The Hind Brain (Rhombencephalon)

    y Medulla breathing, heart rate

    y Pons sleeping, walking, dreaming

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    y Reticular activating system (RAS)

    y From stem reticular fibers

    y Modulates consciousness

    y Distributes neuromodulators

    alertness, attention

    y Cerebellum balance, coordination for the muscles

    y Midbrain / Mesencephalon

    y Extends fr pons to the diencephalon

    y The cerebral aqueduct is its cavity & connects the 3rd

    & 4th

    ventricles

    y Roof of midbrain called tectum & lies posterior to the cerebral aqueduct

    y Made up of 4 rounded bodies known as Corpora quadrigemina

    y The paired upper bodies serve as visual reflex centers for head & eyeball movements

    y The lower bodies are auditory relay centers

    y The Forebrain ( Prosencephalon)

    The Hypothalamus

    - Found inferior to the thalamus, forms the floor & part of the lateral walls of 3rd ventricle

    - Optic chiasm marks the crossing of the optic nerves

    - Infundibulum connects the pit. gld to the hypothalamus

    - Contains centers for body temp control, appetite & satiety, & water balance; regulates pituitary

    gld & links nervous & endocrine systems; helps control autonomic system;

    - It is involved with drives associated with survival such as hunger, thirst, emotion, sex, and

    reproduction

    y Cerebellum

    y behind the dorsal aspect of the pons and the medulla.

    y A midline portion, the vermis, separates two lateral lobes, or cerebellar hemispheres.

    y consists of the cerebellar cortex& underlying cerebellar white matter

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    y 4deep cerebellar nuclei are located within the white matter of the cerebellum

    Because of the location of the fourth ventricle, ventral to the cerebellum,mass lesions or swelling of the

    cerebellum can cause obstructive hydrocephalus.

    y Cerebellum

    A. Paleocerebellum- consists of anterior lobe; controls gross movement of head & body

    B. Nepcerebellum- middle lobe; fine voluntary movements

    C. Archicerebellum- flocullonodular lobe; vestibular system

    y Cerebellar functions (CBP)

    1. coordinating skilled voluntary movements by influencing muscle activity,

    2. controlling equilibrium and muscle tone through connections with the vestibular system

    and the spinal cord and its gamma motor neurons.

    3. There is a somatotopic organization of body parts within the cerebellar cortex.

    4. In addition, the cerebellum receives collateral input from the sensory and special sensory

    systems.

    y Damage to the cerebellum

    y Causes a lack of co-ordination:

    1.

    Speaking

    2. Walking

    3. Tremour

    y Damage can result in ataxic or uncoordinated movement because of errors in the direction,

    range, & rate of movement

    y Characteristic drunken or staggering gait

    y Speech slurred & theres dysmetria (overshooting)

    y Clinical dxtic test; ask pt to place a finger on his / her own nose.

    y (+) will miss mark & may miss several times before finding the target

    y Cerebellar Stroke

    y Dizziness, vomiting

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    y Unsteady so that walking is impossible

    y Power, tone and reflexes normal

    y Area of blood in the cerebellum would show on a CT scan

    y The Nervous System

    1. The spinal cord communicates with the sense organs and muscles below the level of the

    head

    y Bell-Magendie Law- entering dorsal roots carry sensory information and the

    exiting ventral roots carry motor information to the muscles and glands

    y Dorsal Root Ganglia- clusters of neurons outside the spinal cord

    y The Spinal

    Cord,Spinal Nerves,andSpinal Reflexes

    y Spinal Cord

    y Extends from foramen magnum to second lumbar vertebra

    y Segmented

    1. Cervical

    2. Thoracic

    3. Lumbar

    4. Sacral

    y Gives rise to 31 pairs of spinal nerves

    y Not uniform in diameter throughout length

    y Blood Supply

    y Two posterior spinal arteries- supply the posterior 1/3 of the SC

    y Anterior spinal artery- anterior 2/3 of SC

    y Segmental arteries

    y Feeder arteries

    y CSF

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    Shock absorbing fluid that fills ventricles, cavities within the brain & subarachnoid spaces

    around the brain & SC

    Most produced by cluster of capillaries known as CHOROID plexuses (projects fr pia matter into

    ventricles)

    y Cross Section of Spinal Cord

    y Cross Section of Spinal Cord

    y White matter:

    y Myelinated axons forming nerve tracts

    y Fissure and sulcus

    y Three columns:

    y Ventral

    y Dorsal

    y Lateral

    y Gray matter:

    y Neuron cell cell bodies, dendrites, axons

    y Horns:

    y Posterior (dorsal)

    y Anterior (ventral)

    y Lateral

    y Commissures:

    y Gray: Central canal

    y White

    y Gray Matter: Organization

    y Dorsal half sensory roots and ganglia

    y Ventral half motor roots

    y Dorsal and ventral roots fuse laterally to form spinal nerves

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    y Four zones are evident within the gray matter somatic sensory (SS), visceral sensory (VS),

    visceral motor (VM), and somatic motor (SM)

    y White Matter in the Spinal Cord

    y Fibers run in three directions ascending, descending, and transversely

    y Divided into three funiculi (columns) posterior, lateral, and anterior

    y Each funiculus contains several fiber tracts

    y Fiber tract names reveal their origin and destination

    y Fiber tracts are composed of axons with similar functions

    y White Matter in the Spinal Cord

    y Pathways decussate (cross-over)

    y Most consist of two or three neurons

    y Most exhibit somatotopy(precise spatial relationships)

    y Pathways are paired (one on each side of the spinal cord or brain)

    y White Matter: Pathway Generalizations

    y Spinal Nerves

    y 31 pairs: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal

    - each peripheral nerve has 3 layers of CT

    y Epineurium outer tough fibrous sheath

    - dense irregular CT, 1 of collagen fibers and fibrocytes

    - forms the blood-nerve barrier

    y Perineurium composed of collagenous fibers, elastic fibers, and fibrocytes

    - divides the nerve into fascicles (bundle of axons)

    y Endoneurium loose irregular CT

    - capillaries from the perineurium provide oxygen and nutrients ot the axons and Schwann cells

    of the nerve

    Anatomy ofaPeripheral Nerve

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    y Peripheral Distribution ofSpinal Nerves

    y Each spinal nerve forms through fusion of dorsal and ventral nerve roots

    y Distally all spinal nerves form 2 branches

    - a dorsal ramus and a ventral ramus

    y Spinal nerves T1 to L2 contain 4 branches

    - a dorsal ramus and a ventral ramus

    - a white ramus and a gray ramus known as rami communicantes ( communicating branches)

    y Rami Communicantes

    y Carry visceral motor fibers to and from a nearby autonomic ganglion associated with the

    sympathetic division of the ANS

    y White ramus carries fibers to the ganglion

    - contains preganglionic myelinated axons

    y Gray ramus innervate glands and smooth muscles

    - 2 groups of unmyelinated postganglionic fibers that leave the ganglion

    y Dorsal and Ventral Rami

    y Dorsal ramus provides sensory innervation from, and motor innervation to, a specific segment

    of the skin and muscles of the neck and back

    y Ventral ramus supplies the ventrolateral body surface, structures in the body wall, and the limbs

    y Distribution of sensory fibers within these rami illustrates the segmental division of labor

    - each pair of spinal nerves monitors a specific region of the body surface known as a

    dermatome

    Peripheral Distribution of Spinal Nerves (Motor Fibers)

    Peripheral Distribution ofSpinal Nerves (Sensory Fibers)

    y Dermatomal Map

    y Skin area supplied with sensory innervation by spinal nerves

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    y Dermatomes

    y Area of skin innervated by the cutaneous branches of a single spinal nerve.

    y All segments except C1 have dermotomal distribution

    y UE typically from C5-T1

    y LE typically from L1-S1

    y Clinically important -damage to a spinal nerve or dorsal root ganglion produces a loss of

    sensation

    y Sensory Nerve Tracts

    y Transmit action potentials from periphery to brain

    y Each pathway involved with specific modalities

    y 1st

    half of word indicates origin,

    y 2nd half indicates termination

    y Pain

    y Types

    y Referred: Sensation in one region of body that is not source of stimulus

    y Phantom: Occurs in people who have appendage amputated or structure removed as

    tooth

    y Chronic: Not a response to immediate direct tissue injury

    y Peripheral Nervous System (PNS)

    y All nerves that leave the CNS

    y Two Modalities:

    y Peripheral Nervous System

    y Sensory Nerves

    (to the brain)

    Carry messages from special reporters in the skin, muscles, and other internal and external sense organs

    to the spinal cord and then to the brain

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    y Motor Nerves

    (from the brain)

    Carry orders from CNS to muscles, glands to contract and produce chemical messengers

    y Peripheral Nervous System

    y Somatic NS

    Consists of nerves connected to sensory receptors and skeletal muscles

    Permits voluntary action (writing your name)

    y Autonomic NS

    Permits the involuntary functioning of blood vessels, glands, and internal organs such as the bladder,

    stomach and heart

    y Summary ofFunction of Cranial Nerves

    y Cranial Nerve I: Olfactory

    y Arises from the olfactory epithelium

    y Passes through the cribriform plate of the ethmoid bone

    y Fibers run through the olfactory bulb and terminate in the primary olfactory cortex

    y Functions solely by carrying afferent impulses for the sense of smell

    y Cranial Nerve I: Olfactory

    y Cranial Nerve II: Optic

    y Arises from the retina of the eye

    y Optic nerves pass through the optic canals and converge at the optic chiasm

    y They continue to the thalamus where they synapse

    y From there, the optic radiation fibers run to the visual cortex

    y Functions solely by carrying afferent impulses for vision

    y Cranial Nerve II: Optic

    y Cranial Nerve III: Oculomotor

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    y Fibers extend from the ventral midbrain, pass through the superior orbital fissure, and go to the

    extrinsic eye muscles

    y Functions in raising the eyelid, directing the eyeball, constricting the iris, and controlling lens

    shape

    y The latter 2 functions are parasympathetically controlled

    y Parasympathetic cell bodies are in the ciliary ganglia

    y Cranial Nerve III: Oculomotor

    y Cranial Nerve IV: Trochlear

    y Fibers emerge from the dorsal midbrain and enter the orbits via the superior orbital fissures;

    innervate the superior oblique muscle

    y

    Primarily a motor nerve that directs the eyeball

    y Cranial Nerve IV: Trochlear

    y Cranial Nerve V: Trigeminal

    y Composed of three divisions

    y Ophthalmic (V1)

    y Maxillary (V2)

    y

    Mandibular (V3)

    y Fibers run from the face to the pons via the superior orbital fissure (V1), the foramen rotundum

    (V2), and the foramen ovale (V3)

    y Conveys sensory impulses from various areas of the face (V1) and (V2), and supplies motor fibers

    (V3) for mastication

    y Tic douloureuxor trigeminal neuralgia

    - Most excruciating pain known (?)

    - Caused by inflammation of nerve

    - In severe cases, nerve is cut; relieves agony but results in loss of sensation on that side of the

    face

    y Cranial Nerve V: Trigeminal

    y Cranial Nerve VI: Abducens

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    y Fibers leave the inferior pons and enter the orbit via the superior orbital fissure

    y Primarily a motor nerve innervating the lateral rectus muscle (abducts the eye; thus the name

    abducens)

    y Cranial Nerve VII: Facial

    y Fibers leave the pons, travel through the internal acoustic meatus, and emerge through the

    stylomastoid foramen to the lateral aspect of the face

    y Motor functions include;

    y Facial expression

    y Transmittal of parasympathetic impulses to lacrimal and salivary glands (submandibular

    and sublingual glands)

    y

    Sensory function is taste from taste buds of anterior two-thirds of the tongue

    y Cranial Nerve VII: Facial

    y Facial Nerve (CN VII)

    Bells palsy: paralysis of facial muscles on affected side and loss of taste sensation

    Caused by herpes simplex I virus

    Lower eyelid droops

    Corner of mouth sags

    Tears drip continuously and eye cannot be completely closed (dry eye may occur)

    Condition my disappear spontaneously without treatment

    y Cranial Nerve VIII: Vestibulocochlear

    y Fibers arise from the hearing and equilibrium apparatus of the inner ear, pass through the

    internal acoustic meatus, and enter the brainstem at the pons-medulla border

    y Two divisions cochlear (hearing) and vestibular (balance)

    y Functions are solely sensory equilibrium and hearing

    y Cranial Nerve VIII: Vestibulocochlear

    y Cranial Nerve IX: Glossopharyngeal

    y Fibers emerge from the medulla, leave the skull via the jugular foramen, and run to the throat

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    y Nerve IX is a mixed nerve with motor and sensory functions

    y Motor innervates part of the tongue and pharynx, and provides motor fibers to the parotid

    salivary gland

    y Sensory fibers conduct taste and general sensory impulses from the tongue and pharynx

    y Cranial Nerve IX: Glossopharyngeal

    y Cranial Nerve X: Vagus

    y The only cranial nerve that extends beyond the head and neck

    y Fibers emerge from the medulla via the jugular foramen

    y The vagus is a mixed nerve

    y Most motor fibers are parasympathetic fibers to the heart, lungs, and visceral organs

    y Its sensory function is in taste

    y Paralysis leads to hoarseness

    y Total destruction incompatible with life

    y Cranial Nerve X:

    Vagus

    y Cranial Nerve XI: Accessory

    y Formed from a cranial root emerging from the medulla and a spinal root arising from the

    superior region of the spinal cord

    y The spinal root passes upward into the cranium via the foramen magnum

    y The accessory nerve leaves the cranium via the jugular foramen

    y Primarily a motor nerve

    y Supplies fibers to the larynx, pharynx, and soft palate

    y

    Innervates the trapezius and sternocleidomastoid, which move the head and neck

    y Cranial Nerve XI: Accessory

    y Cranial Nerve XII: Hypoglossal

    y Fibers arise from the medulla and exit the skull via the hypoglossal canal

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    y Innervates both extrinsic and intrinsic muscles of the tongue, which contribute to swallowing

    and speech

    y If damaged, difficulties in speech and swallowing; inability to protrude tongue

    y Cranial Nerve XII: Hypoglossal

    y Peripheral Distribution ofSpinal Nerves

    y Each spinal nerve connects to the spinal cord via two medial roots

    y Each root forms a series of rootlets that attach to the spinal cord

    y Ventral roots arise from the anterior horn and contain motor (efferent) fibers

    y Dorsal roots arise from sensory neurons in the dorsal root ganglion and contain sensory

    (afferent) fibers

    y Spinal Nerves: Rami

    y The short spinal nerves branch into three or four mixed, distal rami

    y Small dorsal ramus to back

    y Larger ventral ramus to plexuses/intercostals

    y Tiny meningeal branch to meninges

    y Rami communicantes at the base of the ventral rami in the thoracic region to/from

    ANS

    y Spinal Nerve Innervation:

    Back, Anterolateral Thorax,and Abdominal Wall

    y The back is innervated by dorsal ramivia several branches

    y The thorax is innervated by ventral rami T1-T12 as intercostal nerves

    y Intercostal nerves supply muscles of the ribs, anterolateral thorax, and abdominal wall

    y Nerve Plexus

    y Complex interwoven network of nerves

    y Occurs in segments that control skeletal musculature of the neck and limbs

    - peripheral distribution of the ventral rami do not directly proceed to their peripheral targets

    y Ventral rami of adjacent spinal nerves blend their fibers to produce compound nerve trunks

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    - formed during development when small skeletal muscles fuse to form larger muscles with

    compound origins

    - compound muscles contain sensory and motor fibers

    - ventral rami converge and branch to form compound nerves

    4 Major Nerve Plexuses

    y Cervical plexus

    y Brachial plexus

    y Lumbar plexus

    y Sacral plexus

    y Cervical Plexus

    y Consists of cutaneous and muscular branches in the ventral rami of spinal nerves C1-C4, some

    C5

    y The cutaneous branches innervate areas on the head, neck, and chest

    y The muscular branches innervate muscles of the neck and shoulder

    y Major nerve of this plexus the phrenic nerve provides the entire nerve supply to the diaphragm

    Cervical Plexus

    y Brachial Plexus

    y Formed by C5-C8andT1 (C4 and T2 may also contribute to this plexus)

    y It gives rise to the nerves that innervate the upper limb

    y Trunks andCords of Brachial Plexus

    Nerves that form brachial plexus originate from:

    superior, middle, and inferior trunks

    large bundles of axons from several spinal nerves

    lateral, medial, and posterior cords

    smaller branches that originate at trunks

    y Brachial Plexus: Nerves

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    y Axillary innervates the deltoid and teres minor

    y Musculocutaneous sends fibers to the biceps brachii and brachialis

    y Median branches to most of the flexor muscles of forearm

    y Ulnar supplies the flexor carpi ulnaris and part of the flexor digitorum profundus

    y Radial innervates essentially all extensor muscles

    The Trunks andCords of the Brachial Plexus

    y Brachial Plexus Organization

    y Flow chart summarizing relationships within the brachial plexus - dashed lines to the posterior

    cord merely indicate that the posterior division lie posterior to the anterior divisions

    y Lumbar Plexus

    y Arises from (T12) L1-L4 and innervates the thigh, abdominal wall, and psoas muscle

    y The major nerves are thefemoraland the obturator

    y Sacral Plexus

    y Arises from L4-S4and serves the buttock, lower limb, pelvic structures, and the perineum

    y The major nerve is the sciatic, the longest and thickest nerve of the body

    y The sciatic is actually composed of two nerves: the tibialand the common fibular(peroneal)

    nerves

    y Nerve plexuses - Summary

    y Cervical C1-C4

    y Phrenic nerve

    y Brachial C5 T1 (roots/trunks/divisions/cords)

    y Axillary, MC, median, ulnar, radial

    y Lumbar L1-L4

    y Femoral, obturator

    y Sacral L4-S4

    y Sciatic (common peroneal/tibial), pudendal

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    y Reflexes

    y A reflex is an immediate involuntary response to a specific stimulus

    y The neural writing of a single reflex is referred to as a reflex arc

    Reflexes are classified according to :

    1. Their development (innate and acquired)

    2. The site where information processing occurs (spinal and cranial)

    3. The nature of resulting motor response (somatic and visceral or autonomic)

    4. The complexity of the neural circuit (monosynaptic and polysynaptic)

    Neural Organization- Monosynaptic and Polysynaptic Reflexes

    y 5Patterns of Neural Circuits in Neuronal Pools

    1. Divergence:

    y spreads stimulation to many neurons or neuronal pools in CNS

    2. Convergence:

    y brings input from many sources to single neuron

    y 5Patterns of Neural Circuits in Neuronal Pools

    3. Serial processing:

    y moves information in single line

    y Parallel processing:

    y moves same information along several paths simultaneously

    y 5Patterns of Neural Circuits in Neuronal Pools

    5. Reverberation:

    y positive feedback mechanism

    y functions until inhibited

    y Reflex activity

    y 5 components of a reflex arc

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    y Receptor

    y Sensory neuron

    y Integration center (CNS)

    y Motor neuron

    y Effector

    y Spinal Reflexes

    y Range in increasing order of complexity:

    y monosynaptic reflexes

    y polysynaptic reflexes

    y intersegmental reflex arcs:

    y many segments interact

    y produce highly variable motor response

    y Monosynaptic Reflexes

    y Have least delay between sensory input and motor output:

    y e.g., stretch reflex (such as patellar reflex)

    y Completed in 2040 msec

    y Muscle Spindles

    y The receptors in stretch reflexes

    y Bundles of small, specialized intrafusalmuscle fibers:

    y innervated by sensory and motor neurons

    y Surrounded by extrafusalmuscle fibers:

    y which maintain tone and contract muscle

    y Postural Reflexes

    y Postural reflexes:

    y stretch reflexes

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    y maintain normal upright posture

    y Stretched muscle responds by contracting:

    y automatically maintain balance

    y Polysynaptic Reflexes

    y More complicated than monosynaptic reflexes

    y Interneurons control more than 1 muscle group

    y Produce either EPSPs or IPSPs

    y The Tendon Reflex

    y Prevents skeletal muscles from:

    y developing too much tension

    y tearing or breaking tendons

    y Sensory receptors unlike muscle spindles or proprioceptors

    y Withdrawal Reflexes

    y Move body part away from stimulus (pain or pressure):

    y e.g., flexor reflex:

    y pulls hand away from hot stove

    y Strength and extent of response:

    y depends on intensity and location of stimulus

    y Reciprocal Inhibition

    y For flexor reflex to work:

    y the stretch reflex ofantagonistic(extensor) muscle must be inhibited(reciprocal

    inhibition) by interneurons in spinal cord

    y Crossed Extensor

    Reflexes

    y Occur simultaneously, coordinated with flexor reflex

    y e.g., flexor reflex causes leg to pull up:

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    y crossed extensor reflex straightens other leg

    y to receive body weight

    y maintained by reverberating circuits

    y Integration and Control of Spinal Reflexes

    y Though reflex behaviors are automatic:

    y processing centers in brain can facilitate or inhibit reflex motor patterns based in spinal

    cord

    y Higher centers of brain incorporate lower, reflexive motor patterns

    y Automatic reflexes:

    y can be activated by brain as needed

    y use few nerve impulses to control complex motor functions

    y walking, running, jumping

    y Superficial reflexes

    y Stroking of the skin elicits muscle contraction

    y Involves functional upper motor pathways as well as cord level reflex arcs

    y Plantar reflex (L4-S2) Babinski is normal in infants

    y Usually indicative of CNS damage in adults

    y Abdominal reflex (T8-T12)

    y Absent with corticospinal lesion

    y Spinal Reflexes

    y Spinal Reflexes

    y Spinal Reflexes

    y Spinal Reflexes

    y Spinal Reflexes

    y Spinal Motor Programs

    y Diseases Affecting the Motor System

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    y Spinal Cord Trauma: Transection

    y Cross sectioning of the spinal cord at any level results in total motor and sensory loss in regions

    inferior to the cut

    y Paraplegia transection between T1 and L1

    y Quadriplegia transection in the cervical region

    y THE NEUROLOGICALEXAMINATION

    y NEUROLOGICALEXAM

    y MENTALSTATUS

    y CRANIAL NERVES

    y MOTOREXAM

    y STRENGTH

    y GAIT

    y CEREBELLAR

    y REFLEXES

    y SENSATION

    y MENTALSTATUS

    y Level ofConsciousness

    y Awake and alert

    y Agitated

    y Lethargic

    y Arousable with

    y Voice

    y Gentle stimulation

    y Painful/vigorous stimulation

    y Comatose

    y LANGUAGE

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    y FLUENCY

    y NAMING

    y REPETITION

    y READING

    y WRITING

    y COMPREHENSION

    Aphasia vs. dysarthria

    y MEMORY

    y IMMEDIATE

    y REALLYA MEASURE OF ATTENTION RATHERTHAN MEMORY

    y REMOTE

    y 3 OBJECTS AT 0/3/5 MINUTES

    y HISTORICALEVENTS

    y PERSONALEVENTS

    y ORIENTATION

    y PERSON

    y NOT WHO THEY ARE BUT WHO YOU ARE

    y PLACE

    y TIME

    y OTHERCOGNITIVE FUNCTIONS

    y CALCULATION

    y ABSTRACTION

    y SIMILARITIES/DIFFERENCES

    y JUDGEMENT

    y PERSONALITY/BEHAVIOR

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    y CRANIAL NERVES

    y CRANIAL NERVEEXAM

    y I - OLFACTORY

    y DON TUSE A NOXIOUSSTIMULUS

    y COFFEE,LEMON EXTRACT

    y II - OPTIC

    y VISUAL ACUITY

    y VISUAL FIELDS

    y FUNDOSCOPICEXAM

    y CRANIAL NERVEEXAM

    y III/IV/VI OCULMOTOR,TROCHLEAR, ABDUCENS

    y PUPILLARYRESPONSE

    y EYE MOVEMENTS

    y 9CARDINALPOSITIONS

    y OBSERVELIDS FORPTOSIS

    y V - TRIGEMINAL

    y MOTOR - JAW STRENGTH

    y SENS - ALL3DIVISIONS

    y CRANIAL NERVES

    y VII - FACIAL

    y OBSERVE FOR FACIAL ASYMMETRY

    y FOREHEAD WRINKLING,EYELIDCLOSURE, WHISTLE/PUCKER

    y VIII - VESTIBULAR

    y ACUITY

    y RINNE, WEBER

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    y CRANIAL NERVES

    y IX/X - GLOSSOPHARYNGEAL, VAGUS

    y GAG

    y XI - SPINAL ACCESSORY

    y STERNOCLEIDOMASTOID M.

    y TRAPEZIUS MUSCLE

    y XII - HYPOGLOSSAL

    y TONGUESTRENGTH

    y RIGHTXIITHRUSTSTONGUETO LEFT

    y MOTOREXAMINATION

    y STRENGTH

    y STRENGTH

    y GRADED 0 - 5

    y 0 - NO MOVEMENT

    y 1 - FLICKER

    y 2 - MOVEMENT WITH GRAVITYREMOVED

    y 3 - MOVEMENT AGAINST GRAVITY

    y 4 - MOVEMENT AGAINSTRESISTANCE

    y 5 - NORMALSTRENGTH

    y STRENGTH EXAM

    y UPPER ANDLOWEREXTREMITIES

    y DISTAL ANDPROXIMAL MUSCLES

    y GRIPSTRENGTH IS A POORSCREENING TOOL FORSTRENGTH

    y SUBTLE WEAKNESS

    y TOE WALK, HEEL WALK

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    y OUT OF CHAIR

    y DEEP KNEE BEND

    y Motor exam, cont

    y Subtle signs ofweakness ona cortical/subcortical basis

    y Pronator drift

    y Orbiting

    y Gait evaluation

    y Include walkingand turning

    y Examples ofabnormal gait

    y High steppage

    y Waddling

    y Hemiparetic

    y Shuffling

    y Turns en bloc

    y MUSCLE OBSERVATION

    y ATROPHY

    y FASCIULATIONS

    y ABNORMAL MOVEMENTS

    y TREMOR

    y REST

    y WITH ARMS OUTSTRETCHED

    y INTENTION

    y CHOREA

    y ATHETOSIS

    y ABNORMALPOSTURES

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    y CEREBELLAR FUNCTION

    y RAPID ALTERNATING MOVEMENTS

    y FINGERTO FINGERTO NOSETESTING

    y HEELTO SHIN

    y GAIT

    y TANDEM

    y RombergSign

    y Stand with feet together - assure patient stable - have them close eyes

    y Romberg is positive if they do worse with eyes closed

    y Measures

    y Cerebellar function

    y Frequently poor balance with eyes openand closed

    y Proprioception

    y Frequently do worse with eyes closed

    y Vestibular system

    y REFLEXES

    y MUSCLESTRETCH REFLEXES (DEEPTENDON REFLEXES)

    y GRADED 0 - 5

    y 0 - ABSENT

    y 1 - PRESENT WITH REINFORCEMENT

    y 2 - NORMAL

    y 3 - ENHANCED

    y 4 - UNSUSTAINEDCLONUS

    y 5 - SUSTAINEDCLONUS

    y MSR / DTR

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    y BICEPS

    y BRACHIORADIALIS

    y TRICEPS

    y KNEE

    y ANKLE

    y OTHERREFLEXES

    y Upper motor neurondysfunction

    y BABINSKI

    y present or absent

    y toes downgoing/ flexor plantar response

    y HOFMAN S

    y JAW JERK

    y Frontal release signs

    y GRASP

    y SNOUT

    y SUCK

    y PALMOMENTAL

    y TONE

    y INCREASED,DECREASED, NORMAL

    y COGWHEELING

    y CLASP KNIFE

    y SENSORYEXAM

    y SENSORYEXAM

    y VIBRATION

    y 128 hz tuning fork

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    y JOINTPOSITION SENSE

    y PIN PRICK

    y TEMPERATURE

    Start distally and move proximally

    y HIGHERCORTICALSENSATIONS

    y GRAPHESTHESIA

    y STEREOGNOSIS

    y DOUBLESIMULTANEOUSSTIMULATION

    y BAROSTHESIA

    y TEXTURES

    y Glasgow Coma Scale:

    What is it?

    y Developed by neurosurgeons in 1974

    y Quantifies level of consciousness

    y Acute brain damage: traumatic and/or vascular injuries

    or infections

    y Metabolic disorders: hepatic or renal failure, hypoglycemia, diabetic ketosis, toxic

    ingestion

    y Assess initial level of consciousness

    y Assess changes in level of consciousness

    y Helps guide treatment and predict outcome

    y Glasgow scoring

    y Verbal response in children

    y Posturing

    y Decorticate

    y Upper extremity flexion with lower extremity extension

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    y Mesencephalic region or corticospinal tract damage

    y Decerebrate

    y Upper and lower extremity extension

    y Brainstem damage below the red nucleus

    y Progressive

    y Uncal or tonsilar herniation

    y Stimulation

    y Eye opening

    y Name spoken loudly

    y Verbal response

    y Person, place, time

    y Motor response

    y Fingernail bed pressure

    y Supraorbital pressure

    y Hand crosses midline and above clavicle

    y Sternal rub

    y Glasgow score

    y Score range

    y Extubated: 3 15

    y Intubated: 3 11T

    y Clinical presentation

    y Normal: GCS = 15

    y Comatose: GCS 8

    y Dead: GCS = 3

    y Grading of head injury

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    y Minor: GCS 13

    y Moderate: GCS 9 12

    y Severe: GCS 8

    y Example report

    y GCS 9 = E2 V4 M3 at 07:35

    y Prognosis

    y Prognosis variability

    y Past medical history

    y Age, previous neurological problems

    y Injury

    y Type and location, depth, duration of coma, presence of low blood pressure, oxygen

    levels

    after the injury

    y Current findings

    y Physical examinations, radiological studies of

    the brain

    y Clinical correlate (revisited)

    y The patients eyes, initially closed, opened to the sound of his name.

    y Eye opening

    y 3

    y When asked where he was, the patient said my shoes to change.

    y Verbal response

    y 3

    y The patient moved all of his fingers and toes when prompted.

    y Motor response

    y 6

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    y Score

    y GCS 12 = E3 V3 M6 at 16:34

    y Head injury severity

    y Moderate