Chapter 14 Part 2&3 Flashcards
sensory info is transmitted via
AP’s along sensory pathways (tracts) to the brain
if spinal cord is involved in the sensory pathway=
ascending spinal pathways
each ascending pathway has
specific modalities
what are modalities
types of info transmitted
4 sensory pathways
anterolateral system
dorsal-column/medial lemniscal system
trigeminothalamic tract
spinocerebellar tracts
what does the anterolateral system convey
cutaneous sensory info
conscious perception of pain, temperature, light touch, pressure, tickle and itch sensations to thalamus- cerebral cortex
spinothalamic tract
peripheral receptors to cerebral cortex via 3 neuron sequence which are
primary
secondary
tertiary neuron
what neuron sequence is for dorsal root ganglion
primary neuron
what neuron sequence is for dorsal horn of spinal cord and synapse with interneurons
secondary neuron
what neuron sequence is the thalamus and relay to somatosensory cortex (perception)
tertiary
pain to reticular formation, thalamus
spinoreticular tract
pain and touch to midbrain area (superior colliculi) turn head in direction of cutaneous stimulation
spinomesencephalic tract
what carries sensation of 2 point discrimination, proprioception, pressure and vibration
dorsal-column/ medial-lemniscal system
dorsal-column/ medial-lemniscal system pathway as passes through
brainstream
dorsal-column/ medial-lemniscal system divides into 2 tracts based on
stimulus source
upper 1/2 body is
fasciculus cuneatus
lower 1/2 of the body is
fasciculus gracilis
primary neuron in dorsal-column/ medial-lemniscal system
dorsal root ganglion
secondary neuron in dorsal-column/ medial-lemniscal system
medulla oblongata
tertiary neuron in dorsal-column/ medial-lemniscal system
thalamus
where does the thalamus relay info too
somatosensory cortex
dorsal-column/ medial-lemniscal system gets info from
joints, tendons, and muscles
what carries 2 point discrimination, proprioception, pressure and vibration
trigeminothalamic tract
what does the trigeminothalamic tract detect
pain, temp from face, nasal cavity, oral cavity and teeth
trigeminothalamic tract is afferent for what cranial nerve
CNV
trigeminothalamic tract is tactile afferent ear and tongue via what cranial nerves
CN VII, IX, X
what carried proprioceptive info to cerebellum
spinocerebellar tract
anterior tract from spinocerebellar tract=
info from lower trunk and limbs
posterior tract from spinocerebellar tract
info from upper body in thoracic and upper lumbar regions
primary neuron for spinocerebellar tract of the posterior tract is
dorsal root ganglion
secondary neuron for spinocerebellar tract of the posterior tract is
dorsal horn of spinal cord
what does the dorsal horn of the spinal cord do
synapase with interneurons
tertiary neuron for spinocerebellar tract of posterior tract is
cerebellum
sensation of unpleasant and complex perceptual and emotional experiences that trigger autonomic, psychological and somatic motor responses
pain
the homunculus has what kind of info
sensory and motor
homunculus sensory=
topographic representation of body parts along postcentral gyrus of parietal lobe
homunculus motor=
topographic representation of body parts along precentral gyrus of frontal lobe
correlation for homunculus sensory
various region size (primary somatosensory cortex) to # of sensory receptor in that body area
correlation for homunculus motor
various region size (primary motor cortex) to # motor units in that body
intensely personal experience=
cannot be measured objectively
intensity, but tolerance varies. low pain tolerance vs high is determined by our
genes
how are receptors of pain activated
by xs pressure, temp, and chemicals released from injured tissue
pain reducing analgesic system
brain
endogenous opiods are
endorphins and enkephalins
what are inhibitory neurotransmitters †hat queel pain signals from nociceptors
enkephalins
act as a warning of actual or impending tissue damage, motivates us to take protective action
acute pain
2 components of pain
- rapidly conducted AP carried by large diameter myelinated axons-> well localized cutting pain
- more slowly propagated AP’s carried by smaller, less heavily myelinated axons, resulting in diffuse burning pain
what is visceral pain
Noxious stimulation of Thoracic & Abdominal Receptors = Vague, Dull Ache, Gnaw, Burning sensation
Sensation is long lasting, can be Decreased via Rubbing area around injury, Transcutaneous Electrical Stimulation (TENS), Acupuncture, Massage & Exercise
chronic pain
Pain relieving Meds reduce inflammation & activation of Peripheral nerves, Others block transmissions of pain sensation in Spinal cord in Ascending pathways.
anaalgesics
Painful Sensation in a Region of the body that is NOT the source of the Pain Stimulus & Painful Sensation in a Region of the body that is NOT the source of the Pain Stimulus
referred pain
in referred pain both areas are innervated by what, and project to same what area
neurons
cerebral cortex area
The Brain cannot discern between the 2 sources of painful stimuli & Pain sensation
refers to most superficial structures innervated by converging neurons
what helps to ID actual cause of a Painful Stimulus
referred pain
Myocardial Infarction =
Perceived as Jaw or Left arm pain as T1-T5 spinal segments innervate both areas.
gall bladder=
RUQ & R shoulder
Pancreatitis=
RUQ, LUQ, Radiates to back, also Epigastric area, as is Stomach (GERD).
Occurs subsequent to Amputation of Appendages
phantom pain
Pain perception is projected to what in phantom pain
sensory receptor site, despite sensory receptors are no longer present
lack of what in phantom pain
Lack of Touch, Pressure, Proprioception from Amputated Limb.
When limb Amputated, inhibitory effect of sensory info is removed, this Phantom pain intensity increases
hyperalgesia
what retains image of amputated body part
cerebral cortex
GENERAL ANESTHESIA ONLY=
Spinal cord still had Pain from Amputation.
USE EPIDURAL ANESTHESIA =
Block neurotransmission in Spinal cord (Now use during Sx) = Significant reduction of Phantom Limb Pain incidence.
voluntary movements=
dependent on upper and lower motor neurons
upper motor neurons (UMN)=
Connect Cerebral Cortex to LMN via Interneurons & Cell bodies are in Cerebral cortex
lower motor neurons (LMN)=
Connect UMN to Skeletal muscles & Cell bodies are in Spinal Cord Gray matter & CN nuclei of Brainstem
what are motor pathways
tracts are descending pathways from cerebrum or cerebellum to brainstem or spinal cord
what do motor pathways carry
AP’s along axons that originate in UMN
2 groups of motor pathways
direct and indirect
pyramidal system
direct
extrapyramidal
indirect
what do direct pathways do
maintain muscle tone and control speed and skilled movement precision
2 major tracts of direct pathway
corticospinal and corticobulbar
Involved in direct cortical control of movements BELOW the head
Damage Reduced muscle tone, Clumsy & Weak
corticospinal
Involved in direct cortical control of movements IN Head & Neck
Damage Spasticity, Clonus (Rhythmic Muscle contractions), Hyperreflexia & Babinski sign
corticobulbar
Less precise control over Motor functions, especially those associated with
Overall Body coordination & Cerebellar Function (Posture)
Many interconnections & Feedback Loops exist in this system
indirect pathway
4 major tracts in indirect pathways
rubrospinal
vestibulospinal
reticulospinall
tectospinal
rubrospinal regulates what
Regulates fine motor control in Distal Upper limb muscles
Vestibulospinal maintains
upright posture
Reticulospinal maintains
posture by Controlling Trunk & Proximal Upper & Lower Limb muscles with certain movements
Tectospinal controls
Reflex movement of Head to Bright Lights, Noises & Rapid Movement
what Regulates motor activities: Planning, Organizing, Coordinating Motor Movements & Posture
basal ganglia
feedback loop for basal ganglia
connect basal ganglia, thalamus, cerebral cortex
stimulatory circuits facilitate
muscle activity
inhibitory circuits facilitate
stimulatory circuits by inhibition of muscle activity in antagonistic muscles & also decreased muscle tone when head, body, limbs at rest
what regulates motor activities
cerebellum
3 parts of cerebellum that regulate motor activities
Vestibulocerebellum
Spinocerebellum
Cerebrocerebellum
Vestibulocerebellum does what
maintains muscle tone in postural muscles, corodinates eye movement and controls balance
Spinocerebellum does what
maintains fine motor coordination with simple movements
Cerebrocerebellum does what
plan and practices rapid, complex motor actions that require coordination and training. also cognitive functions
dysfunction in basal ganglia results in
increased muscle tone
exaggerated, uncontrolled movements at rest
resting tremor
dysfunction in cerebellar results in
decreased muscle tone, balance issues
overshoot when reach for object
intentional tremor
higher brain functions include
speech
mathematical and artistic abilities
sleep
memory
emotions
judgement
where is speech located
left cerebral cortex
2 major cortical areas involved and are connected by
neuron bundle
sensroy speech area
wernicke area
where is wernicke area
parietal lobe
what is wernicke are responsible for
understanding and formulating coherent speech
motor speech area
broca’s area
where is broca’s area
inferior frontal lobe
what does broca’s area initiate
complex movement used for speech
damage to broca’s area results in
speech is ok, nonsense language and difficulty understanding
what is aphasia
loss of language abilities due to damage in specific area
AP’s from eyes where word is seen and the word recognize in visual association area
visual cortex
signal representing word is understood
wernicke area
AP’s representing word are conducted through associatioin fibers that connect the 2 areas. formulates the word as it is spoken
Broca’s area
AP’s propagated to premotor area, where movements are programmed. finally, sent to blank where proper movements are triggered
primary motor cortex
what is the sequene of events to speak a word you read
visual cortex
wernicke area
brocas area
primary motor cortex
what is the sequence of events to repeat a word that is heard
primary auditory cortex
wernicke area
brocas area
primary motor cortex
info from ears to blank goes to auditory association area, where word is recognized
primary auditory cortex
signal representing word is understood
wernicke area
AP’s representing word are conducted through assocation fibers that connect the 2 areas and formulated the word as it is spoken
brocas area
signal goes to premotor area, then to
primary motor complex
received sensory info from left side of the body
right cerebral cortex
received sensory info from right side of body
left cerebral cortex
sensory info is shared between hemispheres via
commissure
what skills does the left hemisphere have
analytical
logic
language
what does the right hemisphere do
spatial perception
facial recognition
creativity
intuition
artistic and musical ability
body language
what is consciousness
voluntary initiation and control movement
consciousness has capactities associated with
higher mental processing
what does consciousness involve
simulataneous activity of large areas of cerebral cortex
what is holistic and interconnected
consciousness
in consciousness, information is gathered from
multiple locations in the cerebrum simultaneously
what are the levels of consciousness
alert
drowsy/lethargic
stupor
coma
signal of brain impairment
unconsciousness
brief loss=
fainting or syncope
fainting and syncope is usually due to
inadequate blood flow in the cerebrum , typically from low BP
state of unchanged consciousness or partial unconscious, can arouse by stimulation
sleep
able to arouse by stimulation
sleep
what wakes us up immediately
a strong stimulus
wake up chemicals secreted by hypothalamus is
orexins
sleep requirements
newborn
teens
adults
elderly
newborn: 16 hours
teens: 8-10
adults : 7.5- 8.5
less in elderly
nonrapid eye movement. 4 stages in 1st 30-45 minutes of sleep
NREM
frequency of brain waves and vs decrease, nightmares, and night terrors
NREM
90 minutes (erectiion, enlarged clitoris)
REM
irregular EEG, high body temp, HR, RR, BP, decreased GI motility.
high 02 use; limp
dream
REM
prolonged unresponsiveness to stimuli
coma
is oxygen always below normal levels rest in coma
always below normal levels
brain active and oxygen consumption is similar to being awake
sleep
causative factors for coma
blows to head
tumor or infection
metabolic issues; hypoglycemia
drug OD
liver or kidney failure
irreparable damage to brain, which induces irreversible coma
need to prove legally if alive or dead
life support removed if no brain activity
brain death
different levels of consiousness =
different patterns of electrical activity in the brain
electrodes on scalp record brain’s electrical activity
detect simultaneous AP’s in large #’s of neurons
displays wave-like patterns of electrical activity= brain waves
EEG
produced continuously, intensity and frequency differ based on state of activity, age, brain disease and chemical state of body
brain waves
awake, quiet at rest with eyes closed, calm and relaxed
alpha waves
higher frequency, seen with intense mental activity, concentration
beta waves
in kids, frustrated adults, brain disorder
theta waves
in infants. severe brain disorders, deep sleep, anesthesia
delta waves
what do abnormal EEG diagnose
epilespy, sleep disorders, research brain function
what type of seizure is mild, go blank for few seconds, kids. resolves by age 10
absence
what type of seizure is severe, convulsion, aura, lose bowel and bladder control
tonic-clonic
when seizures are uncontrolled=
no other messages can get through
what is strong, fast moving electrical discharges by groups of brain neurons
seizures
not get necessary amount or quality of sleep
vary 4-9
chronic problem
use hypnotics to sleep
due to jet lag, anxiety and xs caffeine
insomnia
involuntary sleep during daytime
onset without warning
pleasureable event, not control REM circuits
danger with driving, swimming, less orexins
narcopelsyy
treatment for narcolepsy
stimulants and antidepressants
sudden loss of voluntary muscle control, fully conscious, but unable to move
triggered by strong emotions or laughter
cataplexy
temporary cessation of breathing during sleep
awaken suddenyl due to hypoxia
obstructive
sleep apnea
storage and retrieval of previous experiences
memory
fleeting memory of continual event
working memory
7-8 chunks of info
short term memory
limitless capacity (decrease w age)
long term memory
consolidation is
transfer of info from STM to LTM
change STM bank-
emotional state, rehearsal, association, automatic memory
4 types of memory
declarative
procedural
motor
emotional
here and now only. not associate new inputs with old
anterograde amnesia
distant memory lost
retrograde
