neuro-for-the-not- so-neuro-minded barb bancroft, rn, msn, pnp cpp associates, chicago, il...
TRANSCRIPT
NEURO-FOR-THE-NOT-SO-NEURO-MINDED
Barb Bancroft, RN, MSN, PNPCPP Associates,
Chicago, [email protected]
THE FRONTAL LOBES…
• Prime real estate of the brain
• Comprises one-third of the cerebral cortex
• This is your “Mother”• “No, negative, don’t,
stop…” She is inhibitory..
• Socialization
“Mom” and socialization
• Frontal lobes are not mature in babies and young children…it actually takes about 17-22 years for full maturity of the frontal lobes
• “Don’t scratch, don’t pick, don’t dig..”• Judgment• Insight
FRONTAL LOBES…
• Alcohol and socialization
• Loss of inhibitions with .05 blood alcohol levels
• Baso-orbital region and the loss of inhibitions in patients with dementia
Acetylcholine…cognitive function
• Alzheimer’s disease—90% of acetylcholine is lost with destruction of brain tissue
• Amyloid plaques and neurofibrillary tangles
• BAP v.s. TAU
• Tumeric (cucurmin) and beta amyloid
• Acetylcholinesterase inhibitors
Alzheimer’s…
• The Alzheimer’s brain
• Cortical atrophy
• Sulcal widening
• Atrophy of gyri
• Brain weight
Quick mental status check…
• Time and Change Test Clock with hands—What time is it? 3 quarters, 7 dimes, 7 nickels—Can you
give me change in the amount of $1.00?
97% negative predictive value if correct on both parts of the test
Clock drawing…global function
Frontal lobes…
• Voluntary speech center• Dr. Pierre Paul Broca• Broca’s aphasia• Non-fluent aphasia—telegraphic, staccato speech
Frontal lobes…
• Pre-central gyrus (motor cortex—upper motor neurons)
• Voluntary movement center
Upper Motor Neurons/CS tract
• Contralateral hemiparesis• Pronator drift• Hemiparalysis (spastic paralysis)
• Head injury, stroke,tumors
• “And that’s why we always stand to the side when we check reflexes…”
• Hyperreflexia
• Babinski—extensor plantar reflex
TEMPORAL LOBES…
• Wernicke’s area—reception of speech• Do you understand what I am telling you?• Interpretation of speech and sounds• Coins jingling in pocket• Auditory agnosia
TEMPORAL LOBES…
• Cranial Nerve VIII (Acoustic Nerve) “hears” for you…(primary sensory modality)
• The Superior Temporal Gyrus (STG) interprets what you are hearing (higher cortical function)
• What am I hearing?
TEMPORAL LOBES…
• Cranial Nerve I “smells” for you (primary sensory modality)
• The uncus interprets what you are smelling (higher cortical function)
• The uncus is connected to the hippocampus (memory)
TEMPORAL LOBES…
• Inferior surface of frontal and temporal lobes--a meningioma displacing the olfactory nerve (cranial nerve 1)
• Loss of smell
• Loss of inhibitions (baso-orbital frontal lobe)
TEMPORAL LOBES…
• An “aura”—the beginning of a temporal lobe seizure with a funny taste or smell (rotten eggs)
• Anosmia—loss of smell or the loss of the ability to interpret smell may be the first sign of a neurodegenerative disease (PD, DAT)
TEMPORAL LOBES…
• Déjà vu—feeling like you’re been there before• Jamais vu—familiar place becomes totally unfamiliar• Hallucinations—seeing or hearing something that is not
there• Illusions—distortion of an ongoing stimuli
• Drugs and hallucinations—boosting dopamine triggers hallucinations—drugs for Parkinson’s disease, hallucinogenic drugs and mushrooms, ETOH withdrawal, Herpes encephalitis
• Marijuana and illusions
TEMPORAL LOBES…
• Self-preservation and preservation of the species—the autonomic nervous system
• The 4 F’s…fight, flight
• Feeding activities • And….
And…
• Sexual Function
Sexual function in the brain and dopamine…
• SSRIs increase serotonin and you’re happy, but…
• When serotonin goes up, dopamine goes down
TEMPORAL LOBES…
• Self-preservation and preservation of the species—The other 2 F’s
• Flight—Fright (epi, NE)• Episodic dyscontrol syndrome—TBI
patients
TEMPORAL LOBES…
• Recent memory (hippocampus)• Remember 3 items…• Red ball, clock, tennis shoe• Repeat them after me…• Red ball, clock, tennis shoe
• Continue with exam for 10 minutes and ask them to repeat those 3 items
• Post-traumatic stress disorder (cortisol receptors)
• Depression and neurogenesis
Loss of hippocampal cell function
• Loss of recent memory• This is the first neurologic function to go
with the aging process• When does this process begin?• When do you reach your peak mental
capacity?
TEMPORAL LOBES…
• Partial complex seizures—altered state of consciousness; most common cause is a closed head injury; also consider a history of shaken baby syndrome; mid-forceps delivery
• Automatisms
• Semi-purposeful behavior
PARIETAL LOBES…
• Integration of tactile sensations—touch, pressure, vibration, and proprioception (do you know where your left buttocks is, right now?)
PARIETAL LOBES..testing
• Double simultaneous stimuli—kids vs. adults
• Touch two areas at the same time..
• Kids will always neglect their body and will recognize touch on the face
• The neglect syndrome in adults
PARIETAL LOBES..testing
• Ability to localize stimuli• Sharp vs. dull• Tests for proprioception• Graphesthesia
• Apraxia—example: a dressing apraxia ideomotor apraxia constructional apraxia
Abstraction…
• What does “Don’t cry over spilled milk” mean?
• HUH?
• How are a car, plane and boat alike?
• Cow, horse, and pig?
OCCIPITAL LOBES…
• Visual integration—problems manifest as cortical blindness (visual agnosia)
• Do you see this object?
• If they can see it, CN2 (the optic nerve)
• What is it? The occipital cortex
QUIZ…
• What were those 3 items I asked you to remember?
The BASAL GANGLIA…
• The 2nd area of the motor “triad”
The basal ganglia…
• Paired nuclei at the base of the brain
• 50:50 balance between acetylcholine and dopamine
• All dopamine is made in the substantia nigra from melanin
• Gamma-amino butyric acid (GABA) keeps dopamine in check
Substantia nigra
Subthalamic nucleus
Globus pallidus
Caudate nucleus
Dopamine
• Dopamine levels decrease with aging gradually—we all slow down (loss of 45%)
• Dopamine loss of greater than 80% results in signs and symptoms of Parkinson’s disease
The BASAL GANGLIA
The functions of the basal ganglia depend on a balance between various neurotransmitters
GABA-- ↓ dopamine:acetylcholine 50:50When this balance is disturbed, movement
disorders occur
The BASAL GANGLIA…
• Control of movement, initiation and cessation of movement
• Postural reflexes—the righting reflex
Clinical symptoms
• Resting tremor (70%)—unilateral or bilateral (unopposed acetylcholine in Parkinson’s patients)
• Rigidity (decreased dopamine) (vs. spasticity of stroke patients)
• Loss of voluntary movements (spontaneous)• Bradykinesia (decreased dopamine) (check gait)• Postural instability (sternal push)• Presence of severe seborrheic dermatitis
suggests PD (unopposed acetylcholine)• Anosmia
Huntington’s chorea…chromosome #4
• Excess dopamine due to the loss of GABA-minergic input from the degeneration of the caudate nucleus
• Chorea—rapid, jerky movements of muscle groups
• Dementia• Neuroleptic drugs to block dopamine
Other movement disorders
• Tourette’s syndrome
• Athetoid Cerebral Palsy
• Tardive dyskinesia
The cerebellum—the 3rd area of the motor “triad”
The cerebellum…
• Coordination• Synergy• Balance• Equilibrium
The cerebellum…
• Romberg test—stand up with your feet together and close your eyes
• Tandem walk
• Close your eyes and touch your finger to your nose
• Rapid alternating movements
The cerebellum…
• Truncal ataxia—wide, staggering gait
• Dysdiadochokinesia—inability to make rapid alternating movements
• Dysmetria—inability to light on an object (touching nose with finger, for example)
• Dysarthria
• Puppet-like movements
The cerebellum…
• THINK BOOZE and the CEREBELLUM
The CEREBELLUM…
• Multiple sclerosis• Down syndrome• Spinocerebellar ataxia
• (The cerebellum is not “strictly” motor—it also monitors sensory input from “the outside”—may play a role in autism and schizophrenia)
Small cell carcinoma of the lung with mets to the cerebellum
The BRAINSTEM…(the “bulb”)
• Cardiorespiratory center—C2, C3 “Hangman’s fracture)
• ARAS (Ascending reticular activating system)
• Cranial Nerves III – XII (I and II are not located in the brainstem)
The BRAINSTEM…(the “bulb”)
• II (Optic) and III (Oculomotor)—light reflex, accommodation, and the optic disk (papilla)
The BRAINSTEM…(the “bulb”)
• II (Optic) and III (Oculomotor)—light reflex, accommodation, and the optic disk (papilla)
• The Argyll Robertson pupil—it will accommodate but not react (to light)
The BRAINSTEM…
• CN III, IV, VI—follow my finger (extraocular movements)
The BRAINSTEM…
• V (Trigeminal) and VII (Facial)• Corneal reflex—touch cornea with a cotton
wisp and the patient blinks• VII (Bell’s palsy)—paralysis of facial
muscles – smile, puff cheeks, frown
The BRAINSTEM…
• IX (Glossopharyngeal) and X (Vagus)
• The gag reflex
• The uvula
• Closing off nasopharynx—say “K, K, K”
• Cleft palate
The BRAINSTEM…
• CN XII (Hypoglossal)—tongue movement and strength
The PERIPHERAL NERVOUS SYSTEM
• Dermatome chart• Stocking-glove distribution with peripheral
neuropathy• The reflex arc—S1,2 (Achilles),
L3,4(Patellar), C5,6 (Biceps),• C7,8 (Triceps)
Know your dermatome chart…
OR draw your own…
Neuromuscular junction
• Disease of the neuromuscular junction—myasthenia gravis
• Muscle weakness—consider thyroid disease, drug-induced myopathy, polymyositis, inherited muscular dystrophies
The reflex arc…
• Sensory information into the spinal cord• Synapses in same spinal cord segment• Sent right back out via lower motor neuron
to• Peripheral motor nerve• S1,2 (Achilles); L3,4 (Patellar); C5,6
(Biceps); C7,8 (Triceps)• 50% of the elderly (over 75) do NOT have
an Achilles reflex
Disease of the lower motor neuron or it’s pathway to the peripheral nervous system
• Diabetes, alcoholism (thiamine deficiency), trauma, B12 deficiency
• Heavy metals
• Chemotherapy
• others
Thanks.
• Barb Bancroft, RN, MSN, PNP• CPP Associates, Inc.• Chicago, IL.• [email protected]• www.barbbancroft.com