W5: NeuroPsych Flashcards
Nervous system overview
Central: Brain and spinal cord
Periph: cranial nerves, spinal nerves and pathways (neurons/NT)
The _____ is an integrated circuit composed of millions of neurons and receives 15-20% of cardiac output. This organ allows people to reason, function intellectually and express themselves.
Brain
Nerve injury- 2 pathways (lecture-more)
- Axonal
- Demylinization
Perpih Nervous System:
Somatic: motor/sensory, regulating motor control of skeletal muscle
Autonomic: motor/sensory regulating body’s internal environ. through involuntary control of organs
Sympathetic
Parasympathetic
Neurons what do they do and the 3 components function
Neuron: primary info/comms. cell; vary in size/structure
Cellular:
microtubules (transport)
Neurofibrils (structure sup)
Nissl Substances (protein synth)
-Some neurons-olfactory continue to divide, others die if not needed
- Cell body (soma) located in CNS; nuclei-desnsely packed
ex: ganglia and plexuses-groups in the PNS - Dendrites (receptive portion)
-sends signals to the cell body
-Dendritic Zone: receptive portion of neuron rec’ing signals and cont. conduction - Axons: (carry away from cell)
Axon hilcock: cone-shaped, organelle-free, area where axon leaves the cell body-closest portion has lowest threshold for stim.
Axons: what happens if injured
Myelin: segmented layer of lipids; insulating,
myelin sheath: Entire membrane; formed and maintained by SCHWANN cells
endoneurium: delicate layer of connective tissue around each axon
Neurilemma (Schwann sheath) thin membrane b/w myelin sheath and endoneurium
Neuroglia=”nerve glue”
5-10x > than neurons
astrocytes: fill space b/w neuron & surrounding Blvessels
Oligodendroglia: deposit myelin within CNS
Microglia: remove debris
Ependymal: line CSF cavities
Schwann Cells: aka neurolemmocytes
glial cells, wrapping around/covering axons in the PNS
Form/maintain myelin sheath
myelinated: wrapped tightly, many times around axons, creating-NODES of RANVIER
increasing velcocity of signal
Neurotransmitters-common types & effects postsynaptically
Types:
norepinephrine
acetylcholine
dopamine
histamine
serotonin
post-synapse:
excited-depolarized
inhibited: hyper polarized
Neurotransmitters & receptors
When neurotransmitters release their contents into the ______ ____, they diffuse across and bind to receptors on the ____ synaptic neurons and trigger an ____ ______
1 synaptic cleft, 2. post, 3. action potential
The parasympathetic system is also known as the ______ system due to it’s affinity for _______ which binds to ______ receptors
cholinergic, 2. acetylcholine, 3. muscarinic
Discuss Action Potential- all or none phenomenon
An action potential is a brief reversal of the electrical potential across the membrane of excitable cells like neurons and muscle cells. It is the fundamental mechanism by which information is transmitted along these cells.
threshold potential -55mV, voltage gated NA channels open allowing influx of + sodium—rapid depolarization to +30mV
Propogation of AP:
The depolarization zone propagates away from the initial site, causing adjacent regions to also depolarize in a wave-like manner by opening voltage-gated Na+ channels. This allows the action potential to travel rapidly along the axon toward the axon terminals
In myelinated cells, the AP jumps from node of Ranvier to Node, increasing in velocity
Repolarization and refractory
after peak, NA channels deactivate allowing in K+, therefore repolarinzing membrane back to resting potential.
During absolute refractory: right after peak, the neuron CANNOT generate another charge
Anatomy of the brain-3 major divisions
- Forebrain: two cerebral hemispheres
- Midbrain: corpora quadrigemina, tegmentum, and crebral peduncles
- Hindbrain: cerebellum, pons, and medulla
Forebrain: telencephalon
Cerebrum
-cerebral cortex
-basal ganglia
-Gyri, sulk, and fissures
-gray matter (nuclei) and white matter (numberous tracts)
Brainstem: reticular formation
Midbrain, medulla, and pons
Retic: network of connected nuclei that reg. vital reflexes (cardio/resp)
maintains wakefulness
w/ cerebral cortex is refered to as reticular-activating system
Frontal Lobe: (know functions for stroke purposes)
Prefrontal: goal-oriented behavior; short-term mem/recall
premotor: programs motor movement; in the basal ganglia or extrapyramdial sys
efferent pathway outside of medulla pyramids.
primary motor area: homunculus (little man)
corticospinal tracts (pyramidal system) DESCEND the spinal cord. Contralateral control
Broca speech area:
Motor aspect of speech
Parietal, occipital & temporal lobes
parietal: somatic sensory input
occipital: visual cortex
temporal: auditory cortex
wernicke area (rec/interpr speech)
long-term memory
Corpus callous, limbic system, and Diencephalon
Corpus callous: aka transverse commissural fibers; connects the two hemispheres
Limbic: primitive behaviors/responses, visceral reactions to emotion/motivation, mood, feeding, biorhythms, and sense of smell;
Consolidation of memory
Diencephalon-
-epithalamus
-thalimus
-hypothalamus
-subthalamus
The _______ is composed of four areas: the ____ which forms the roof of the third ventricle and superior area, the ______ manages afferent (sensory) impulses to the cerebral cortex, the ______ maintains a constant internal environment by controlling the ______ nervous system via body temperature and endocrine function and finally the ______ serves as a center for motor activities.
Diencephalon, 2. epithalamus, 3. Thalamus, 4. hypothalamus, 5. autonomic, 6. subthalamus
Midbrain (mesencephalon)
Corpora quadrigemina (tectum): superior vision/inferior auditory
Tegmentum: red nuclei (motor output) and substantia nigra (synth dopamine)
Cerebral peduncles
Cerebral Aquaduct (Silvius) carrie CSF
HindBrain: (metencephalon)
Cerebellum-conscious & union. muscle synergy; maintains balance/posture
Damage- ipsilateral (same side) loss of equillibrium, bal, and motor coordination
Pons: helps control respiration
Medulla oblongata (myelencephalon) controls:
HR, RR, BP, cough, sneeze, swallow, & vomitting
Spinal cord: reflex arc
-receptor
both afferent & efferent neurons
Motor effectrs from the reflex arcs generally occur before the perception of the event in the higher centers of the brain
upper and lower neurons
What are some motor pathways (pyramidal system)
corticospinal (contalateral; voluntary movement of skeletal mucles and fine motor control)
corticobulbar (ipsilateral; vol movement of facial muscles, head and neck via the cranial nerves)
reticulospinal (medial tract=motor activity, lateral tract=inhibits motor activity; modulate muscle tone and locomotor patterns)
vestibulospinal (medial: extensor tone; lateral: facilitates flexor tone)
rubrospinal (red nucleus in midbrain; facilitates fflexor tone and suppresses extensor muscles.
Tectospinal: midbrain to coordinate visual reflexes like head/eye movements towards a stm.
what are sensory pathways
Anterior Spinothalamic tract
vague touch
Lateral spintothalamic tract
pain/temperature
Posterior (dorsal) column
Fine touch, 2-pt discrimination & proprioception;
3 neuron chain
Ipsilateral transmisson
contralateral transmission
Which ion causes neurotransmitter vesicles to fuse into the pre-synaptic membrane? (from class notes
Calcium
Protective structures
Cranium (8 bones)
meninges-referred pain (around brain & spinal column)-dura matter, arachnoid, & pia matter
Spaces
subdural-b/w dura & arachnoid
subarachnoid: contains CSF &b/w arachnoid and pia matter
epidural: b/w dura matter & skull
CSF &ventricle system
Vertebral column-33 vertebrae, C, T, L, &S w/ intervertebral discs
CSF facts
125-150 mL in the ventricles
prevents the brain from tugging on the meninges, nerve roots, and BV
produced by the choroid plexuses in lateral, 3rd &4th ventricles
reabsorbed thru the arachnoid villi
exerts pressure within brain & Spinal cord
Blood supply to the brain
800-1000 mL/min
CO2 primary regulator for cns blood flow
*internal carotid
*vertebral arteries
*Circle of Wiles
*Blood brain barrier
*what is the fxn (need more)
Cranial Nerves
1- olifactory/sensory
2-optic/sensory
3-oculomotor/motor
4-trochlear/motor
5-trigeminal/mixed
6- abducens/motor
7- facial/mixed
8- vestibulococchlear/sensory
9-glossopharyngeal/mixed
10-vagus/mixed
11-spinal accessory/motor
12-hypoglossal/motor
Neuro receptors of the ANS
Functions of Autonomic NS
stim of the sympathetic nervous
-decreases parastalsis
- incr blood, temp, and BP
-regulates vasomotor
Stim of a the parasympathetic
-promotes rest/tranqulity
-reduces HR
-Enhances visceral fxn for digestion
-controls pupil constriction and tears
-increases salivary secretions
-contracts urinary bladder
Age: structural changes
of neurons decreased
brain wt/size decreased
fibrosis and thickening of the meninges
narrowed gyri and widened sulci
increased ventricles
cell changes:
decr myelin
deposition of lipofuscin
presence of senile plaques
multiple neurofibrillary tangles
Lewy Bodies
Fxnal changes:
dim sensory fxn
sleep disturbances
memory impairments
Afferent vs. Efferent pathways (blueprint)
Afferent and efferent pathways refer to the directional flow of information in the nervous system.
afferent neurons/sensory: carry sensory information (information gained through touch, smell, pain temperature, & others) from the body’s receptors TO the brain and spinal column
Efferent (motor): carry motor information AWAY from CNS to periphery, signals to initiate actions/responses
Tests of nervious system function (what do they show, and what are you looking for when you order them)?
Xray: roentgenograms
CT (bleeding, clots, or other abnorms)
CTA (CT w/ contrast in vascular- shows collateral circ)
MRI (magnetic fields to create detailed pics of brain tissue, detects brain tissue damaged by ischemia)
MRA: MRI w/ contrast to visualize blood flow through arteries and detect narrowing or clots
Positron-emission tomographic (PET)
Cerebral angiography (die)
single photon emisson CT (SPECT)
myelography (dye)
Echoencephalography (U/S)
EEG (brain waves) Seizure activity w/ abnormal spikes
Evoked potentials (stim activated)
CSF (L3 or L4 interspace) infection/ pressures
Magnetoencephalography (MEG)
Functions of pain
adapative measure to avoid further tissue damage
protective measure
evoked responses:
w/d from noxious stim (spinal reflexes)
anticipatory movement (shielding face w/ arm)
pain threshold vs tolerance
threshold:
lowest intensity of pain that a person can recognize
intense pain at 1 loc., may increase threshold at another location
tolerance:
greatest sensitivity to pain that a person can endure
-very individualized; varies greatly among persons over time
Pathways of pain modulation
add pic
pain inhibitors:
Opiods
GABA
Cannabinoids
Serotonin
Norepinephrine
Pain facilitators
Glutamate
Substance P
Histamine
Prostaglandin
Bradykinin
Ear anatomy (blueprint)
Olifactory terminology (blueprint)
CN 1 and part of 4
taste and smell
hyposmia: impaired smell
Anosmia: complete loss of smell
Olfactory hallucinations: hyperactive cortical neurons smell odors that aren’t there
Parosmia: abnorm/perverted sense of smell
Types of hearing loss(blueprint)
Conductive: (CHL) sound cannot be conducted through middle ear (occular chain & tympanic membrane)
Sensorineural (SNHL): impaired organ of Corti or connections; cochlea, cranial nerve 8, central auditory pathways)
_Presbycusis: age-related
Mixed: combo of the above
Functional: can be born with, no organic cause
Ear infections
Otitis externa
otitis media
externa: inflam/infect outer ear; aka swimmers ear, or prolonged moisture exposure
tx: topical abt
media (acute): infect in middle ear w/ retention of fluid
-MC pathogens: strep pneumonae, H. influenza, Moraxella catanhalis
-Fever, otoalgia, decr hearing
DX: hx, otoscope (bulging membrane w/ decr mobility
tx: abt or sug if recurrent (“tubes” often in children)
Lumbar puncture landmarks (blueprint)
the line connecting both iliac crests. This crosses the vertebra column at the level of the L4-L5 intervertebral space or L4 vertebra.
Types of cerebral edema (blueprint)
Cytotoxic: d/t failure of ion pumps, leading to intracellular fluid accumulation
Vasogenic: MC; involves the break down of the blood brain barrier, allowing fluid to leak into the extracellular space; often asso w/ tumors.
Interstitial edema AKA: transependymal ) when CSF moves into the brain parenchyma; often asso w/ hydrocephalus
Osmotic: from osmostic gradient b/w blood and brain tissue, causing water to move into brain cells
Hydrostatic: incr capillary pressure leading to fluid movement to extracelluar space
High altitude edema
hemorrhagic d/t brain bleed
ICP-increased intercranial pressure (blueprint)
SERIOUS-rise in pressure inside cranium
C/B: brain injury/traume
brain tumors
hemorrhage
swelling
hydrocephalus (excess CSF)
infections- meningitis or encephalitis
stroke
aneurysm rupture
HTN
s/s:
severe HA, N/V, blurred or diplopia, confusion/change in mental state,
weakness/difficulty w/ movement, seizures, LOC, changes in pupil size & reactivity.
Dx: phys exam, CT/MRI, LP, or insertion of ICP monitor into brain
tx: meds to reduce swelling, draining excess csf, surgical removal of tumors/clots, or part of skull to relieve pressure. Tx underlying cause
Prevent: wear protective head gear, managing underlying conditions-HTN,
Pupillary response(blueprint)
Types of Seizure activity (blueprint)
Focal
Generalized 4
Status epilepticus-see other slide
Seizures are a symptom, recurrent SZ=epilepsy (aura)
*Differentiation b/w SZ &epilepsy: LOC, Motor/Sensory deficits, and behaviors.
Focal (aware and impaired awareness)
Generalized:
tonic-clonic (grand-mal)
Absence (petit mal)
Atonic (drop sz)
tonic
clonic
Consequences of: increased blood flow
incr O2 consumption (60% more)
glucose depletion
accum of lactate–lots of sequelae-brain injury, exhaustion of brain cells.
Seizure sequence
Resting potential instability
Seizure start-bursts of AP
Tonic, Clonic, post-ictal phases
Note: important psychosocial SE-embarassment, loss of control, sudden, etc
Status epilepticus-more severe
more consequences
Increaseses in:
tremendous incr in ATP
incr cerebral O2 consumption (60%)
glucose depletion
hypoxia
acidosis
injury to brain
body injury d/t tonic/clonic-bite tongue, vertebral fractures
Psycho social:
alienated relationships
school/family/friends
unpredictable and scarry for others around.
Subdural hematoma (blueprint)
medical emergency
a blood vessel near the surface of the brain ruptures, causing bleeding into the space between the brain and the outermost membrane covering the brain (the dura mater). This accumulation of blood puts pressure on the brain,
acute vs chronic
s/s: phys &neuro exam, CT, MRI
tx: depends on size/location
lg: surgery-craniotomy or burr hole to drain the blood
sm: managed w/ meds, obs, monitoring
Coup and coutnercoup brain injury (blueprint)
fowrard and backward brain injury from force of originial hit
coup-frontal
countercoup-back of brain
both happen together-These injuries occur because the brain is floating in cerebrospinal fluid within the skull. When a sudden impact or deceleration occurs, the brain can slam against the inside of the skull, causing bruising, bleeding, or other damage. The initial impact causes the coup injury, while the rebounding of the brain against the opposite side of the skull causes the contrecoup injury
C/B: trama, mva, sports injury
s/s: HA, memory loss, sensory or motor fxn deficits, Cog impiarments, sev cases=coma/paralysis
Gulian barre -
Periph NS
MC cause of acute paralysis
MC nerve illness of the PNS
MEDICAL EMERGENCY
Acquired, acute, inflammatory autoimmune ds;
Acute immune mediated polyneuropathy;
Demyelination of the periph nerves or axonal d/o
several types:
mc: has immune component d/t VIRAL exposure or offending vaccine (CMV, Epstein-barr, HIV, micoplasma or flu-like illness, or bacterial campylobacter
Manif: rapid progression of weakness of limbs from distal point and ASCENDS upward, leading to systemic flaccid paralysis
TX: vent support
mgmt of autonomic dysfxn
IVIG, plasmaphoresis (shortens process), aggressive rehab after symp subside
90%affected achieve full recovery 2-6 weeks to up to 2 years.
Multiple Sclerosis CNS demyelination
1 demyelinating ds in world.
MC reason for disability-life limiting
prevents normal conduction of nerve signal (slow/blocked)
W>M
age of onset: 20-40’s
Progressive, chronic, inflammatory, autoimmune (T cell mediated immune reaction by oligodendracytes)
occurs in gray & white matter
exam: hard/white patches of nerve; plaques in CNS
2 types/stages of lesions:
1: inflamm
2. Scaring
S/s: relapsing/remitting
progressively worsen
each relapse will worse ds. speech changes, dysphagia, vision changes-diplopia, abnorm gait,
Tx: NO CURE, mgmt sympt.
steroids, immunotherapy, Vit D, stem cells
Depression serum marker changes (blueprint)
increase in inflammatory markers
CRP, IL-6, IL-12, and tumor necrosis factor (TNF-a)
Enzyme: MAO-A
hormones: decr estrogen/progesteron
Basic sleep disorder terminology
dyssomnia: intrinsic/extrins. sleep d/o and cirrcadian ryth. d/o (hard to fall or stay asleep)
-insomnia
-osa
- RLS
-obesity hypovent
-hypersomnia-excess daytime sleepiness
Narcolepsy: hypersomnia, cataplexy, hallu, sleep paralysis
Parasomnias: arousal and sleep/wake transition d/o; REM sleep d/o
-sleepwalking; night terrors
-d/o r/t REM sleep
-sleep paralysis, nightmares, osa, SIDS
Sleep d/o asso w/ med/psych d/o
Proposed sleep d/o
Proprioceptive dysfunction
Vestibular nystagmus-constant involun. eyeball movement; over stim semicircular canal system
Vertigo: sensation of spinning r/t inflam of semicircular canals
Menieres ds: idiopathic, episodic, vestibular d/o r/t abnorms of endolymph in mid ear
peripheral neuropathies
VIsion disorders
Blepharitis: inflam of eyeball
hordeolum (stye)
Chalazion (non-infect, lipogranuloma of oil gland)
Entropion: eyelid malposition, margin turns against eyeball
**Conjunctivitis: inflam of conjunctiva (pink eye), highly contagious, mucopurlulent drng
-viral
-allergic
-chronic
–trachoma (chlamydial) leading cause of blindness in world
Visual dysfunction (terms) Acuity
Strabismus: deviation from one eye to the other (diplopia-double vision)
nystagmus: invol uni/bi lateral rhythmic movement
cataracts: cloudy/opaque vision loss
galucoma: optic nerve neuropathy–>atrophy of optic nerve (pressure-: 12-20 in aqueous fluid)
Retinal detachment: if lost vision=emergent
separation of neurosensory retina from retinal pigmnented epithelium in the chorcoid (incr fluid accum)
progressive vision field loss
photoopsia: flashes of light
floaters: hrs or weeks
*once detachment occurs, visual prog=poor
alterations in vision Refraction of light
Myopia: in front of retina, c/b eye too long w/ too much curvature
r/s: cant focus distant objects
Hyperopia: behind retina; c/b eye too short, cornea w/ decr curvature
r/s: can’t focus near objects
Astigmatism: multiple sites, c/b uneven curvature; =blurry vision
Data processing terminology
Agnosia: fx to recog the form and nature of objects
Aphaisa: loss of comprehension/production of language
Dysphasia: expressive vs receptive or transcortial
acute confusional states: delerium
Dementias
3 types of dysphasia
Wernke’s: disturbance in understanding all language-verbal and reading
Conductive: disruption of temporal lobe fibers w/ fx to repeat words but ability to initiate speech, writing, and reading aloud
Anoic: inability to name objects, people, or qualities
Transcortical: Brocha’s area
