Exam 1 Flashcards
1
Q
Choroid Plexus
A
-produces CSF
-web of capillaries
-blood filtered 3x
2
Q
Lateral Ventricles
A
-above thalamus
-2
-connected to 3rd ventricle by inter-ventricular foramina (Monro)
3
Q
3rd Ventricle
A
-surrounded by diencephalon
-connected to 4th ventricle via cerebral aqueduct (sylvius)
4
Q
4th Ventricle
A
-behind pons/medulla
-connects to central canal of SC
-drains into subarachnoid space via foramina of Luschka and midline foramen of Magendie
5
Q
Falx Cerebri
A
-dense projections in inner layer of dura
-separates 2 hemispheres
6
Q
Tentorium Cerebelli
A
-dense projections in inner layer of dura
-separate cerebellum from cerebrum
7
Q
Homunculus Motor Cortex
A
-Precentral Gyrus
Medial: Genitals, toes, ankle, knee
Superomedial: trunk, hip, shoulder, elbow, wrist, hand
Superolateral: Hand (fingers pinky-thumb), face
Lateral: Face (top to bottom), jaw (talking), tongue (swallowing)
8
Q
Homunculus Sensory Cortex
A
-Postcentral gyrus
Medial: Genitals, toes, ankle, knee
Superomedial: trunk, hip, shoulder, head, arm
Superolateral: Hand (fingers pinky-thumb), elbow, forearm, wrist
Lateral: Face (top to bottom), jaw, tongue, gums, pharynx
9
Q
Vertebrobasilar A.
A
-posterior circulation of brain
10
Q
Posterior Inferior Cerebellar A. (Think of location)
A
-bottom, posterior cerebellum
11
Q
Anterior Inferior Cerebellar A.
A
-front and bottom cerebellum
12
Q
Superior Cerebellar A.
A
-top of cerebellum
-under CN III
13
Q
Posterior Cerebral A.
A
-posterior cerebrum
-occipital lobe
-Posterior, medial, inferior temporal lobe
-above CN III
14
Q
Internal Carotid A.
A
-anterior circulation of brain
15
Q
Ophthalmic A.
A
eyes
16
Q
Posterior Communicating A.
A
-connects PCerebralA and ICA
-connects 1 side of ant to post
17
Q
Anterior Cerebral A.
A
-medial cerebral hemisphere to parietal lobe
-from ICA
18
Q
Anterior Communicating A.
A
-between ant. cerebral A.
19
Q
Middle Cerebral A.
A
-lateral cerebral hemisphere
EXCECPT:
-superior and front parietal
-inferior temporal
20
Q
Vertebral A. Stroke
A
-prone to shear forces from AA joint from abrupt cervical rotation
-gait issues, ataxia, HA
21
Q
Basilar A. Stroke
A
-complete blockage causes death
-partial: tetraplegia, numbness, CN damage, locked in syndrome (only movements)
22
Q
Anterior Cerebral A. Stroke
A
-hemiparesis loss to contra side
-personality changes
-lower limb issues
23
Q
Middle Cerebral A. Stroke
A
-hemiparesis loss to contra side
-face and upper limb issues
L side: aphasia
R side: spacial relationships, nonverbal communication
24
Q
Posteror Cerebral A. Stroke
A
-midbrain issues (thalamic syndrome), eye movement issues, cortical blindness (brain cant comprehend vision)
25
Pontine Arteries
-supplies pons
26
Torcula
-confluence of sinuses
-drains straight sinus and sup. saggital sinus
-drains to sigmoid
27
Cavernous SInus
-drains from blood supply of face and brain
-drains to sigmoid
28
Superior and inferior Petrosal Sinus
-drains from cavernous sinus
-drains to sigmoid
29
Frontal Lobe
Voluntary Movement, language, higher level function
30
Parietal Lobe
Sensory perception, sensory integration (5 senses)
31
Occipital Lobe
-visual perception
32
Temporal Lobe
-auditory processing, vestibular, memory formation
33
Post central gyrus
-Primary sensory cortex
-proprioception
-sensory input
34
Pre central gyrus
-primary motor cortex
-voluntary movement of contralateral side
35
Central Sulcus
-boundary btwn motor/sensory and parietal/frontal lobes
36
Lateral Sulcus
-separates temporal from frontal and parietal lobes
37
Cerebellum
-coordinate movements
38
Pons
-unconscious processes
-sleep, breathings
39
Medulla
-vital processing (breathing, BP, HR)
40
Mammillary Bodies
-recollective memory
41
Fusiform Gyrus
-high level vision
-face perception, object recognition, reading
42
Inferior Olive
-learning and timing of movements and comparing them to intended movements
43
Pyramids and Decussation
-motor fibers that pass from brain to medulla oblongata
-SC nerves cross
44
Uncus
-olfaction
-emotions
-forming new memories
45
Parahippocampal Gyrus
-spatial awareness
-memory encoding
46
Midbrain
-vision, hearing, motor control, arousal, temperature regulation
47
Middle Cerebellar Peduncle
-connects cerebellum to pons
-largest
- contains afferent fibers
48
4th Ventricle
-protect brain
-form central canal
49
Inferior Colliculus
-sound localization
-pitch discrimination
-integration of auditory information
50
Superior Colliculus
-visual (directing eye movements), auditory processing for orienting toward environment , auditory, and somatosensory spatial information integration
51
Substania Nigra
-production of dopamine
-body movements
-part of basal ganglia
-on midbrain
52
Cerebral Peduncles
-refining fine motor movements
conversion of proprioceptive information into balance and posture
53
Gracile Fasciculus
-main touch pathway
-fine touch, vibrations, conscious proprioception
-lower body to brain stem
54
Cuneate Fasciculus
-only in cervical
-vibration and conscious perception and fine touch sensations from upper body
55
Gracile Nucleus
-medulla
-dorsal column nuclei
-fine touch sensation and proprioception of lower body
56
Cuneate Nucleus
-info from upper body
-medulla
57
Inferior Olivary Nucleus
-coordinate signals from SC to cerebellum to regulate coordination
58
Periaqueductal Grey Matter
-modulation and propagation of pain
59
Cranial Nerve Locations
Midbrain: CN III-IV
Pons: CN V-VIII
Medulla: CN IX-XII
60
CN I Exit Foramina
Cribriform plate
61
CN II Exit Foramina
Optic canal
62
CN III & IV & VI Exit Foramina
Superior orbital fissure
63
CN V Exit Foramina
V1: superior orbital fissure
V2: foramen rotundum
V3: foramen ovale
64
CN VII & VIII Exit Foramina
Auditory canal
65
CN IX & X & XI Exit Foramina
Jugular foramen
66
CN XII Exit Foramina
Hypoglossal foramen
67
CN I
Olfactory (sensory)
-smell (olfactory cortex: amygdala, parahippocampal gyrus, uncus, insula)
-only sensory input that reaches cortex before thalamus
1) cover 1 nostril and smell different
CI
Anosmia: loss of smell
-avulsion of olfactory fibers
68
CN II
Optic (sensory)
-visual acuity (visual cortex: occipital lobe)
Optic Nerve: from eyes
Optic Chiasm: crossing
Optic tract: to visual cortex
1) consensual contralateral light response (midbrain)
2) eye chart
CI
Homonymous Hemianopsia: damage in contralateral visual path results in ipsilateral 1/2 blindness
69
CN III
Oculomotor (motor)
-eye and eyelid movement
1) eye movements except lateral and down/in
2) consensual ipsi light response
3) cover eye and pupillary constriction of contra
CI
External Strabismus: ipsilateral eye fixed in abd
Ipsilateral ptosis: paralysis of upper eyelid
Diplopia: double vision
Mydriasis: Ipsilateral pupuil fully dilated
70
CN IV
Trochlear (Motor)
-ipsilaterally eye movement (down and in)
-only CN that exits dorsum of brainstem
1) H test
CI:
Cannot down and in
-double vision
-difficulty reading
-head tilt to opposite side
71
CN V
Trigeminal (Both)
V1: Opthalamic (sensory)
V2: Maxillary (sensory)
V3: mandibular (both)
Motor: clench jaw and feel masseter and temporalis
Sensory: check in forehead (ophamalic), checks (maxillary), and jaw (mandibular)
CI:
Corneal Blink Reflex
-tactile sensation on cornea
Trigeminal Neuralgia
-sharp pain in face
72
CN VI
Abducens (motor)
-lateral eye movements
-H test
CI:
-double vision
73
CN VII
Facial (both)
Motor: facial expression and salivary, stapedius of ear
Sensory: tongue and pharynx
Parasympathetic: salivary gland
Special Sensation: ant 2/3rd of tongue
Testing
-Motor:
1) smile
2) frown
3) move eyebrows
Sensory:
-close eyes and place sweet/salt on anterior 2/3rds of tongue
CI
Bell’s Palsy
74
CN VIII
Vestibulocochlear (sensory)
-hearing and vestibular
Hearing:
1) rub fingers together
2) whisper word identification
3) Weber Test: tuning fork on head
4) Rhine Test: tuning fork on mastoid
Vestibular:
1) touch nose then pt finger
2) turn head while looking at thumb
CI:
-vertigo, conductive or sensorineural deafness
75
CN IX
Glossopharyngeal (Both)
-Motor: stylopharyngeus
-Parasympathetic: parotid salivary gland, carotid a.
-Sensory: 1/3 pos tongue, soft palate, ear, gag reflex
Sensory:
1) sour/bitter taste on posterior 1/3 tongue
Motor:
1) swallowing
CI:
decreased gag reflex and salivation
76
CN X
Vagus (both)
Motor: larynx, pharynx, tongue, gag
Parasympathetic: decrease HR, bronchoconstriction, digesiton
Test
1) saw ah, uvula deviation to strong side
2)Swallowing
CI:
-hoarseness and swallowing difficulties, digestion issues
77
CN XI
Accessory (motor)
-SCM and trap
-Cell bodies in ventral horn of C1-C4
-travels through foramen magnum and exits jugular foramen
Test
1) shoulder shrug
2) head turning
78
CN XII
Hypoglossal (motor)
-tongue movements
-swallowing
-speaking
1) stick tongue out, deviates to weak side
CI:
-Dysphagia: difficulty swallowing
-Dysarthria: poor control of speech muscles
-LMN: flaccid tongue, deviates to weak
-UMN: tongue deviates to strong side
79
Thalamus
-interprets sensation information and perceives it
80
Name of Pathways
-origin and site of termination for 2nd order neruon
81
Types of Somatosensory Pathways to Brain
Conscious Relay:
-info about location and stimulus type to conscious awareness
-discriminative sensations
Divergent:
-info to many locations in brainstem and cerebrum
-conscious and non-conscious
Non-Conscious Relay:
-proprioceptive and other movement to cerebellum
82
Conscious Relay Pathways
-info about location and stimulus type to conscious awareness
-discriminative sensations
Crude Awareness: thalamus
Detailed Awareness: somatosensory cortex
Dorsal Column
Anterolateral Column
83
Divergent Relay Pathways
-info to many locations in brainstem and cerebrum
-conscious and non-conscious
-medial/slow nociception
-subconscious temperatue
Spinomesencephalic, spinoreticular and spino-emotional tracts
84
Non-Conscious Relay Pathways
-proprioceptive and other movement to cerebellum
Spinocerebellar Tracts
85
Descending Motor Fibers (2 types)
Pyramidal Tracts: cerebral cortex
Extrapyramidal Tracts: Brainstem
86
Flexor-Extensor Rule
-MNs that innervate flexors are located posteriorly to MNs that innervate extensors
87
Proximal-Distal Rule
-MNs that innervate distal muscles are located laterally to MNs that innervate proximal muscles
88
Lateral Corticospinal Tracts (function)
-crossed at pyramidal decussation of medulla
-fractionated movements
-primary motor cortex
-most CST fibers
-descends in lat funiculus
89
Medial Corticospinal Tracts (function)
-uncrossed
-postural movements
-originates from premotor cortex
-descends in venttral funiculus
90
Nonspecific Motor tracts
-facilitate activity of interneurons and MNs
-activate during intense emotions
Ceruleospinal and Raphespinal Tracts
91
Corticobrainstem Tracts
-voluntary control of many MM of head and neck
-originate in cortex motor areas and reach CN nuclei in brainstem
92
Secondary Somatosensory Gyrus
-post to primary
-processes info from primary and thalamus for stereognosis and sensory memory
93
Crista Gali
-separates olfactory bulbs
94
Cribiform Plate
Olfactory N.
95
Optic Canal
-optic N and ophthalmic A.
-loss of vision
96
Foramen Rotundum
- Maxillary portion of Trigeminal
-loss of function at maxilla
97
Foramen Ovale
-mandibular portion of trigeminal
-loss of function at mandible
98
Formamen Spinosum
-middle meningeal artery
-epidural hematoma
99
Foramen Lacerum
-filled with cartilage
100
Groove for Meningeal A.
-middle meningeal artery
-epidural hematoma
101
Grove For Petrosal Sinus
-sup. petrosal sinus
-improper drainage
102
Internal Auditory Meatus
-Facial N and Vestibularcochlear n
-Hearing loss and facial paralysis
103
Jugular Foramen
-CN 9,10,11
-int. jugular vein
-Loss of taste, uvula deviation, speech, neck muscles, bleeding out
104
Sulcus for Transverse Sinus
-transverse sinus
-improper drainage
105
Hypoglossal Canal
-Hypoglossal nerve
-weak tongue muscles
106
Foramen Magnum
-SC, vertebral arteries, Accessory N
-Death, paralysis
107
Sulcus for Superior Saggital Sinus
-sup. saggital sinus
-improper drainage
108
Superior Orbital Fissure
-Trigeminal N, opthalamic A, abducens N, occulomotor N, Trochlear N
-Loss of vision, pupil reaction, eye movements
109
Stylomastoid Foramen
-facial N
-Face paralysis and abnormal taste
110
Homonymous Hemianopsia
damage in contralateral visual path results in ipsilateral 1/2 blindness
111
External Strabismus
: ipsilateral eye fixed in abd
112
Ipsilateral ptosis:
paralysis of upper eyelid
113
Diplopia:
double vision
114
Mydriasis:
Ipsilateral pupuil fully dilated
115
Secondary Somatosensory Gyrus
-post to primary
-processes info from primary and thalamus for stereognosis and sensory memory
116
Dorsal Column Medial Leminiscus
-Ascending tract
-Light touch, proprioception, sterognosis
1st: Dorsal horn ganglion to FG or FC
2nd: Nucleus Gracilis or Cuneatus in Medulla
CROSS with Internal Arcuate Fibers at Medial Leminiscus
3rd: Thalamus to PSSC
117
Anterolateral System
-ascending tract
-crude touch
Anterior: crude touch
Lateral: Fast nociception and temp
1st: Dorsal root ganglion to DH
CROSS at Anterior Commissure
2nd: Anterior commisure and travels up LST to thalamus
3rd: Thalamus to PSSC
118
Medial Nociception
-dull/slow pain
-ascending, divergent pathway
1st: C fibers with free ending in DH
CROSS
2nd:
Spinomesencephalic: Sup. colliculi and periaqueductal grey
Spinoreticular: Reticular Formation
Spinoemotional: Cortex
-reaches consciousness
119
Dorsal Spinocerebellar
-ascending, LE, uncrossed
-Nonconsious postural movements
-coordination and proprioception
1st: DRG to via FG Clark's Nucleus
2nd: Up DPT through Inferior Cerebellar Peduncle to Cerebellum
120
Ventral Spinocerebellar
-ascending, LE, crossed, bilateral
-Nonconsious postural movements
-coordination and proprioception
1st: Anterior Hron
CROSS
2nd: Up VPT through Superior Cerebellar Peduncle
CROSS to Cerebellum
121
Cuneocerebellar
-ascending, UE, uncrossed
-Nonconsious postural movements
-coordination and proprioception
1st: DRG to Nucleus Cuneatus
2nd: Up NC through Inferior Cerebellar Peduncle to Cerebellum
122
Rostrospinocerebellar
-ascending, UE, uncrossed
-Nonconsious postural movements
-coordination and proprioception
1st: DRG to Superior Cerebellar Peduncles to cerebellum
123
Medial/Ventral Corticospinal Tract
-automatic trunk movements, uncrossed
-pyramidal
Premotor cortex > internal capsule > Cerebral Peduncle (midbrain)> FG> medial/anterior horn
124
Lateral Corticospinal Tract
-voluntary limb mmts
-pyramidal
Primary Motor Cortex> internal capsule> Cerebral peduncles (midbrain)>crosses at decussation of medulla>FC>lateral horn
125
Corticobulbar Tract
-facial movements
-Pyramidal
Primary motor cortex> cerebral peduncles> crosses a lot at CNs> exits cervical ventral horn
126
Reticulospinal Tract
-extrapyramidal
-postural and gross movements (walking), extensors
Reticular formation in Pons>FG>ventral horn
127
Vestibulospinal Tract
-extrapyramidal
-postural and vestibular movements
Medial: head and neck motions to maintain position
Lateral: limb and trunk reactions to gravity
Vestibular Nuclei in Pons and medulla>lateral column>ventral horn
128
Spinal Cord I Zone
-dorsal horn
-marginal zone
129
Spinal Cord II Zone
-Dorsal horn
-Substantia gelatinosa
130
Spinal Cord III Zone
-dorsal horn
-Nucleus proprius
131
Spinal Cord IV Zone
-dorsal horn
-Nucleus proprius
132
Spinal Cord V Zone
-Dorsal horn
133
Spinal Cord VI Zone
-dorsal horn
134
Spinal Cord VII Zone
-intermediate zone
-Clark's nucleus
135
Spinal Cord VIII Zone
-ventral horn
-commissural nucleus
136
Spinal Cord IX Zone
-ventral horn
-motor nuclei
137
Spinal Cord X Zone
-grey matter
-Grisea centralis
138
Glia Cells
-non-neuronal cells
-supportive, homeostasis, regulation
139
Neuron function
Reception, integration, transmission, and transfer of information
140
Bipolar Neurons
-1 dendrite, cell body and 1 axon
-sensory
141
Pseudounipolar Neurons
Dendrites, axon and cell body on side
-motor
142
Multipolar Neurons
Multiple dendrites
-interneurons
-most common
143
Macroglia
-larger supporting cells
-Astrocytes
-Oligodendrocytes
-Schwann Cells
144
Microglia
-immune for CNS
-phagocytes
145
Astrocytes
-macroglia cells in CNS
-support, signal, nutrtients
146
Oligodendrocytes
-macroglia cells in CNS
-create myelin
147
Schwann Cell
-PNS macroglia
-support PNS and make myelin
-does all the job
148
Local Potential
-small, graded
-occurs in receptor or synapse
-spreads passively
149
Action potential
Large "all or none"
-depolarizing
150
Resting Membrane Potential
-70mV
151
Ion Cell Distribution at Rest
More Na+ outside, more K+ inside
-Extracellular positive charge outside
-Intracellular negative charge inside
-more permeable to K+M
152
Movement of K+ during AP
-diffuses down concentration gradient and towards negative charges
-chemical gradient force out, electrical gradient force in
2K+/3Na+
153
4 Membrane Ion channels
Leak (non-gated): small amount leak, K+
Modality-gated: Sensory neurons only; mechanical, temp or chemicals
Ligand-gated: opens when stimulated by neurotransmitters
Voltage-gated: opens when reaction; Ca+
154
Movement of Na+ during AP
-moves through leaky channels and then voltage gated negative charges
2K+/3Na+
155
Spatial Summation
I.....I......I......I
156
Temporal Summation
AP combine to form a large AP.
-Build up of multiple excitatory waves merging
157
Depolarization
-voltage gated channels release Na+ into cell
- polarity becomes positive
158
Repolarization
-Na+ channels close, K+ voltage channels open and release to the outside of the cell
159
Hyperpolarization
K+ gates remain open and cause hypo
-90mV
160
Absolute Refractory Period
completely unresponsive to stimuli
-Na+ has not reset yet
161
Relative Refractory Period
May respond to higher stimuli
-Most Na+ resets
162
Factors Influencing AP
-diameter of axon, larger=faster
-myelin, more=faster
-temperature, warm=faster
163
Nodes of Ranvier
-site of saltatory conduction
-location of AP generation and depolarization
-high density of voltage gated ion channels
164
Conduction Speeds of fibers
large myelinated: PNS sensory and motor
Thin unmeylinated:
-short axons in grey matter in CNS
-visceral ANS axons
-pain fibers
165
Muscle Cell AP vs neuron
-90mV RMP
-AP 1-5msec
-18x slower than neuron
166
Presynaptic Terminal
-neuron conducting impulse toward synapse
-feet
-release neurotransmitters/neuromodulators
167
Postsynaptic terminal
-dendrite or cell body receiving neurotransmitter
168
Axosomatic Synapse
-synapse that binds to cell body of another nerve
-local membrane potential
169
Axoaxonic Synapse
-synapse that binds to axon of another nerve
-1st neuron activates second
-presynaptic effects
170
Axodendritic
-synapse that binds to dendrite of another nerve
-local membrane potential
171
Steps of Synaptic Transmission
1. AP comes to presynaptic terminal
2. Presynaptic membrane depolarizes and releases Ca+
3. Ca+ causes vessicles to exocytose neurotransmitters
4. Neurotransmitter binds to postsynaptic receptor
5. Postsynaptic receptor opens ion channel or triggers intracellular messengers
172
Excitatory Postsynaptic potential (EPSP)
-local depolarization with Na+ or Ca+ into neuron
-facilitates AP generation
-common throughout CNS and PNS
173
Inhibitory Postsynaptic Potential (IPSP)
-local hyperpolarization with K+ out of neuron
174
Presynaptic Facilitation
-1st presynaptic neuron (Axoaxonic) releases neurotransmitters that attaches to 2nd neurotransmitter (axosomatic) and slightly depolarizes it to releases Ca+
175
Presynaptic Inhibition
-1st presynaptic neuron (axoaxonic) causes slight hyperpolarization to decreased Ca+ released from 2nd neuron (axosomatic)
176
Neurotransmitters
-fast
-released from synapse
-EPSP and IPSP
-ms to mins
177
Neuromodulators
-extracellular space
-alter gene expression, open iono channels, change metabolism, affects many neurons
-mins to days
178
Ligand-Gated Ion Channels
-fast response
-aka ionotropic receptor
-some excitatory and inhibitory
-inactivate due to lack of neurotransmitter and resorption
179
Guanine Nucleotide Binding Protein Activation of Ion Channels
-alters electrical excitability or neurons
-Neurotransmitter being to G protein and alter the shape
-Internal subunit breaks away and binds to membrane ion channel to change shape and open
-slower than ligand
-Mood disorders, Parkinson's, Alzheimer's
180
Agonist
-drugs the bind to receptors and copy actions of neurotransmitter
181
Antagonists
-drugs that block postsynaptic neurotransmitter
-drugs that inhibit release of neurotransmitter in presynaptic neurons
182
Acetylcholine (Ach)
-Neurotransmitter produced in basal forebrain above eyes and midbrain (at top of brainstem)
-Skeletal Muscles: Ach for neuromuscular junctions for muscle contraction. Blocking: causes weakness, fatigue, paralysis
-Autonomic NS: slows HR, constricts pupils
-Brain: Arousal, pleasure, cognitive function, movement and attention. Pleasure seeking behaviors and alzheimers
183
Glutamate
-amino acid principal fast neurotransmitter of CNS
-Neural changes w/ learning and development (neuroplasticity)
Excessive:
-excitotoxiciity and neuron death
-seizures
Associated with
-chronic pain, Parkinson's, schizophrenia, neuron death, stroke
184
GABA
-Glycine and y-aminobutyric acid
-animo acid primary inhibitory neurotransmitter that prevent excessive neural activities in CNS (downers)
Glycine: inhibits postsynaptic in brainstem and SC
Low Levels:
-seizure, involuntary muscle contractions, anxiety
185
Huntington's Disease
-causes loss of neurons that use GABA
-causes jerky, involuntary movements and cognitive decline
186
Dopamine
-amine neurotransmitter produced in substantia nigra of the brain
-affects motor function, cognition, and behavior, reward seeking behaviors (good for eating, bad for addiction)
-2nd messenger systems
Abnormalities seen in:
-Parkinson's: not enough dopamine; bradykinesia, treat with precursor
-Schizophrenia: signalling pathways, treat with drugs that prevent binding
Excessive:
-drug abuse by preventing reuptake of presynaptic terminals
187
Norepinephrine
-amine neurotransmitter produced in brainstem, hypothalamus, and thalamus
-released by neurons of ANS and adrenal glands
-fight or flight
Excessive:
-fear, panic, PTSD
-beta blockers to treat
Low:
-sleeping
-depression
188
Serotonin
-amine neurotransmitter involved with mood, pain, arousal, and motor acitivities
High
-alert and during REM
Low
-depression
189
Opioid Peptides
-endogenous: endorphins, enkephalins, dynorphins
-produced in NS and bind to receptors for opium
-receptors in SC, hypothalamus, brainstem to inhibit pain
190
Substance P
-peptide that stimulates nerves at injury site
Neurotransmitter: acts on CNS to cary info to brain
Neuromodulator:
-pain syndromes
-hypothalamus and cerebral cortex during long duration excitation
-modulate immune activity during stress
191
Ways to Restrict of # Receptors
-internalize receptor
-inactivate receptor
192
Increase of # receptors
-infrequent activate
-low levels of neurotransmitters
193
Lamber-Eaton Syndrome
-antibodies damage Ca channels in presynaptic membrane
-no Ach release
-muscle weakness
194
Myasthenia Gravis
-antibodies damage receptors on muscle cells
-Ach released but cannot bind
-muscle fatigue
-life threatening
195
Pre-Embryonic Stage
0-14 days
-Inner cell mass of cells becomes embryonic disc
-endoderm and ectoderm
196
Embryonic Stage
15dy- 8wks
-3 layers
197
Ectoderm
-NS
-epidermis
198
Mesoderm
-CS
-Excretory sys
-dermis
-muscles
-skeleton
199
Endoderm
-Respiratory sys
-organs
200
Fetal Stage
8wks - Birth
-myelination starts
201
Neural Tube Development
18-26 days
-Neural groove done at 21d
-closes at cervical 1st
-Superior neuropore closes at 27d
Inner layer
-grey matter
-dorsal horn: sensory
-ventral horn: motor
Outer layer
-white matter
202
Somites
-appear in occiput first, the caudally
Anteromedial: vertebrae and skull
Posteromedial: muscles of myotome
Later: dermis/dermatome
203
Conus Medullaris
-end of SC
-l1-l2
204
Cauda Equina
-individual nerves extending at end of SC
-starts at L1-L2
205
Filum Terminale
-connection of meninges at end of SC
206
SC Growth
-stops at 4-5
-vertebral column stops at 16-18y
207
Grey and White Matter
SC:
Grey: outside, unmyelinated
White: inside, myelinated
Brain:
Grey: inside, unmeylinated, cell bodies
White: outside, myelinated
208
Brain Development
Hindbrain: brainstem (w/o midbrain), 4th ventricle
Midbrain: cerebral aquaduct
Forebrain
Posterior: Diencephalon
Anterior: telencephalon (cortex, white matter, lateral ventricles
209
Abnormal Neck and reflexes
-Asymmetric tonic reflex
-Symmetric tonic reflex
-Tonic labyrinth reflex
210
Neural Tube Defects
-Anencephaly: head does not develop
-Chiari Malformation: foramen magnum contains part of brainstem
-Spina Bifida
-Tethered cord syndrome: filum terminale is stretched
211
Geriatric Cognition
-decreases everywhere
-long term memory and procedural are stable
-retention of new info stable but needs more cues
-visual recognition of objects are stable
-decrease in vocabulary
212
Atypical Cognition Aging
-mood changes
-visual-spacial changes
-memory changes
-difficulty communicating
213
Mild cognitive impairment
-do not interfere with ADLS (unlike dementia and Alzheimer's)
-90% develop alzheimer's
-gradual, opposite of learning
214
Causes of Aging Changes
-25% of motor neurons die
-myelin fragmented
-less dendrite density, less neurotransmitters, less synapses
-shrinkage
215
3 Neuron Pathways
1st: sensory receptor to SC or BS
2nd: SC or BS to thalamus
3rd: Thalamus to cerebral cortex
216
Stimulus
-when applied to a receptor, triggers graded membrane potential
-determines type of receptors activated
217
Receptor
-converts stimulus into AP
-specialized and responds only to specific stimulus type and intensity
218
Conduction
AP travels to CNS
219
Translation
CNS receives, integrates info, prepares response
220
Receptor Morphology
-different shapes/functions of receptors
Simple Receptors: unmyelinated, free nerve endings
Complex Neural receptors: myelinated, nerve endings enclosed in connective tissue
Special Senses Receptors: Myelinated, release neurotransmitters onto sensory neurons
221
Special Senses Receptors
-somatic: tactile, thermal, pain, proprioceptive
-Visceral: internal organs
222
Exteroceptors
-near body surface
-external stimuli
223
Interoceptors
-deep
- comes from body
-BP, blood pH, proprioception
224
Nociceptors
-occur in all receptors that are sensitive to stimuli that either damage or have damage potential
-can take a scenic route instead of going to the brain
225
Proprioceptors
-muscles, tendons, ligaments, tendons
-position and kinesthetic sense
226
Photoreceptors
-vision
227
Tonic Receptors
-respond continuously if stimulus remains
-slow adapting
-detect object pressure (static)
Book laying on hand
228
Phasic Receptors
-adapt to continuous stimulus and then stop responding even with stimulus
-fast adapting
-motion, vibration, rate of change
Wearing glasses, clothing on body
229
Afferent Axon diameter decreasing diameter
Ia, Ib, II, III, IV
AB, ADelta, C
230
Sensory neuron receptive field
-area of skin innervated by 1 afferent nerve
-smaller fields with greater densiy distally, more sensitivity
-larger fields proximally, less sensitivity
231
Cutaneous Receptors
Superficial, subcutaneous, mechanoreceptors (AB), Free nerve endings (Adelta & C)
-all go to the same peripheral nerve bundle
232
Superficial Cutaneous Receptors
-small receptive field, epidermis and dermal palpalae
-Meisner's Corpuscles: light touch, vibration (superficial)
-Merkel's Discs: pressure (deeper)
233
Subcutaneous Cutaneous Receptors
-large receptive field, dermis
-Pacinian Corpuscle: touch, vibration (deeper)
-Ruffini's ending: stretch (more superficial)
234
Mechanoreceptors
-light touch, vibration, stretch, pressure
- AB fibers
235
Free nerve endings
-ADelta & C fibers
-course touch, pain, temperature
236
Conduction
-3rd step of sensory system
Determinants:
-Modality: specialized stimulation
-Location
-Intensity: # and frequency of activated receptors
-Duration
237
Signal Integration Levels
3 Levels
-Receptor Level: normal receptor/stimulus interaction; more stimulus more reaction
-Circuit level
-Perceptual Level
238
Circuit Level of Integration
-Divergence: synapses spread AP to several areas of CNS
-Convergence: synapses can focus action potentials from several sensory neurons on narrowed area
239
Perceptual Level of Integration
-sensory tract caries impulse to respective region of the brain
-testing comes in to determine what level of integration is faulty
240
Nerve Conduction Velocity Tresting
Electrical stimulation to peripheral nerves (NCV)
Looks at
-Distal latency: time from stimulation to distal recording sight (testing myelination)
-Amplitude: # of axons conducting
-Conduction Velocity: indication of myelin
Somatosensory evoked potentials (SSEP)
-tests peripheral and central pathways
stimulation at distal sight recording proximally
241
Clinical Implications : Peripheral Nerve Lesions
-neuropathy
-Nerve compression: large first then small
Order of sensory loss
-proprioception and light tough
-cold
-fast pain
-heat
-slow pain
242
Clinical Implications : Sensory Ataxia
-injury to dorsal column, roots, or nerves
-EC vs EO testing
Cerebellar: cannot adapt, same with EC/EO, intact proprioception
Sensory: can adapt with EO/EC, impaired proprioception
243
Clinical Implications : Varicella Roster
-Shingles
-painful rash in dermatome pattern
-chicken pox remains dormant in sensory ganglia then travel to nerve endings
244
Nociceptive Pain
-acute or chronic tissue injury stimulates nociceptors to become perception of pain
245
Non-Nociceptive pain
-malfunction of neural pain without the presence of injury
-neuropathic pain, central sensitivity, pain syndromes
246
Pain Control
Central Processing:
-cingulate and insula during perception of pain
Endogenous Opioids:
-endorphins bind to opiate receptors
Spinal Cord:
-inhibitory neurons
-enkephalin and dynorphin
Segmental Level of Control:
-Gate control theory
-non nociceptive fibers closes a gate for nociceptive fibers
247
Pain inhibition (at each level)
Periphery: decreases prostaglandins,
-Gate control theory: non nociceptive fibers closes a gate for nociceptive fibers
Dorsal Horn: release enkephalin or dynorphin
Brainstem: descending system
Hormonal System: pituitary gland and periaqueductal grey
Cortical Level: prefrontal, insular, and cingulate lobes
-spinolimbic, spinomesencephslic, and spinoreticular tracts
248
Referred Pain
-visceral tissues to skin
-convergence of nociceptive and somatic info
249
Chronic Pain
Disease (Primary pain):
-no biological function or tissue damage
Ex: fibromyalgia, migraines
Symptom (secondary pain):
-symptom of another condition
-continuous stimulation of nociceptors from tissue injury
-even after healing
-damage to somatosensory system
250
Central Sensitization
-CNS responds excessively to continuing nociceptive input
-cause changes to cells reactiveness
-pain top-down regulation disturbed
251
Paresthesia
-abnormal sensation
-dysfunction of neurons
252
Neuropathic Pain
-pain from direct lesion or disease
-Dysesthesias
253
Dysesthesias
- abnormal sensation that can occur on it's own or from stimulation
Allodynia, hyperalgesia, spontaneous pain, temporal summation
254
Allodynia
pain caused by something that normally doesn't cause pain
255
Hyperalgesia
-Primary: excessive sensitivity to normal pain
-Secondary: pain spreads to uninjured areas
256
Spontaneous Pain
pain unrelated to external stimulus
257
Temporal Summation
-increased pain due to repeated stimulus
258
Fibromyalgia
-tenderness and stiffness of muscles and tissues
-widespread pain
-increased pain without stimuli
259
Complex Regional Pain Syndrome
-not related to nerve or nerve root distribution
-affects distal limb
-abnormal response to trauma
-central sensitization with functional changes in brain
Sx: red or pale skin, edema, stiff joints, muscle atrophy, tremors
260
Nonspecific Low Back Pain
-no specific injury
-muscle guarding and abnormal movements
261
Ectopic Foci
-cause pain
-outside of nociceptors and become unmyelinated, increasing sensitivity to stimuli
262
Ephaptic Transmission
-Cross Talk
-lack of insulation due to demyelination that allows 1 action potential to affect more than 1 neuron
-cause for allodynia
263
Structural Reorganization
-long term central sensitization causes CNS rewiring
-new synapses carry more nociceptive information
264
Small Fiber Neuropathy
Partial central sensitization cause by :
-post-herpetic neuralgia: shingles
-diabetes
-gulliain barre syndrome (polyneuropathies)
265
Phantom Limb Sensations
-sensations related to posture, length, and movement of missing limb
Residual Limb Pain:
-easier to treat then Phantom limb pain
Phantom Limb Pain:
-absence of sensory inputs causing nociceptors to be overactive
266
PT Clinical Implication (chronic pain)
-considered psychosocial aspects of chronic pain
-Consider: distress, disuse, and disability
267
Muscle Spindle Components
-on skeletal muscles to sense stretch
Intrafusal Muscle in non-contractile regions
-Dynamic nuclear bag (1a, dynamic y)
-Static Nuclear Bag (1a, II, static y)
-Nuclear Chain (1a, II, static y)
Large Diameter myelinated sensory receptors
-central regions of fibers
Small Diameter myelinated motor endings
-innervate polar contractile regions
268
Extrafusal Muscle Fibers
Outer skeletal muscle that generate movement by attaching to tendon
269
Intrafusal Muscle Fibers
Inner skeletal muscles that form spindle
-non-contractile
-proprioceptors (length and velocity)
270
Nuclear Bag Fibers
Type of Intrafusal Fibers
-centrally located
-large
Static
Dynamic
271
Nuclear Chain Fibers
Type of intrafusal fiber
-smaller
-length dependent
-activate alpha motor neurons
272
Ia Fibers
-primary sensory endings on muscle spindle
-phasic and tonic discharges
-changes to length
273
IIa
-secondary sensory endings
-tonic discharges
-responds to steady state length
274
Gamma Motor Neuron
-regulate sensitivity of muscle spindle fibers
-innervate polar regions and stretch
-motor supply to intrafusal fibers
Dynamic: innervate dynamic NB, increase sensitivity of Ia
Static: innervate NB and NC, increase tonic activity both, decrease dynamic sensitivity Ia
275
Alpha-Gamma Co-activation
Gamma: innervate polar regions and initiate stretch causing; mechanical gated channels to depolarize on intrafusal fibers
Alpha: .... contract the muscle to maintain length-tension relationship
276
Reciprocal Inhibition
-1 muscle contracts and opposing muscle is inhibited
1. Intrafusal fiber senses stretch
2. Info travels to dorsal horn
3. Interneuron
4.Travels to ventral horn
5. Opposite muscle
277
Golgi Tendon Organ
-proprioceptive structures at junction between muscle fibers and tendon
-sensitive to stretch in tendon/contraction of muscle
-innervated by Ib fibers that send AP to
278
GTO Motor Control
-afferent signal from GTO relaxes muscles OR activates muscles depending on receptors and feedback
279
Motor Neuron Pools
-clusters MNs in SC
-innervate a single muscle
Medal MN: innervate axial and proximal limb muscles, laterally, distal
Ventrally MN: innervate extensors and dorsal flexors
280
Small MNs
-innervate slow twitch fibers
-less force
-long periods of time
281
Large MNs
-fast twitch fibers
-large forces
-fatigue quickly
282
Rate Coding
-MN signals amount of force exerted by muscle
283
Size Principle of MNs
-smaller MNs are recruited and fire before larger
Ohm's Law: V=IR (voltage= current x resistance)
284
Transverse Tube
(T-tube)
-surrounds sarcoplasmic reticulum and propagates
285
Sarcoplasmic Reticulum
-released acetylcholine
-stores Ca+
286
Z Line
-fibrous disc at end of each sarcomere
287
M line
-holds together fibers at sarcomere center
288
Titin
-maintains actin/myosin positions to prevent them from being pulled apart
289
Troponin
-calcium binding causes tropomyosin to move and uncover sites on actin
290
Muscle Tone
Resistance to stretch of a muscle
291
Muscles immobilized in shortened position
-lose sarcomeres
292
Muscles immobilized in lengthened position
Gain sarcomeres
293
Phasic Stretch Reflex
-DTR
-muscle contraction in response to quick stretch
-monosynaptic
294
Cutaneous Withdrawl Reflex
-monosynaptic
-response to pain, withdrawal/flexion before consciously aware of pain
295
Muscle Cramps
-painful contractions due to overstimulation of nerve tracts
296
Fasciculations
-fast twitches of all motor fibers in a MU
-eyelash twitching
297
Myoclonus
-brief contractions of a group of muscles
298
Tremors
-involuntary rhythmic movements
-with movement or at rest
299
Polio and post-polio syndrome (types)
1. normal MU
2. death of selected MUs
3. Neuroplasticity cause giant motor units
4. Muscle fatigue and pain
300
CN of PNS
I and II
301
Order of Nerve Naming (CNS to PNS)
Rootlets
Root
Spinal Nerve
Rami
Peripheral Nerve
302
Axoplasm
-transports nutrients and chemicals
-allows nerves to glide
-becomes viscous when stationary
303
A-Alpha Nerve Fibers
-fastest and thickest
-Muscle spindles and golgi, touch, MNs
304
Ia Nerve Fibers
-fastest and thickest
-muscle spindle
305
A-Beta Nerve Fibers
-2nd thickness and speed
-touch, muscle spindle
306
A-Gamma Nerve Fibers
-3rd thickest
-touch, pressure, gamma MNs
307
Ib Nerve Fibers
2nd-thickness
-golgi tendon organs
308
II Nerve Fibers
3rd thickest
-touch, muscle spindle
309
III
-pain, crude touch, pressure, temp
-touch, muscle spindle
310
A-delta Nerve Fibers
-pain, crude touch, pressure, temp
311
B Nerve Fibers
-preganglionic autonomic
312
C Nerve Fibers
-slowest, thinnest
-pain, crude touch, pressure, temp
-postganglionic autonomic
313
IV Nerve Fibers
-Slowest, thinnest
-pain, crude touch, pressure, temp
314
Cervical Plexus
-C1-C4
315
Lumbar Plexus
-L1-L4
316
Sacral Plexus
-L5-S4
317
Peripheral Neuropathy
-any disease of peripheral nerves
318
Mononeuropathy
-single nerve involvement
Traumatic Myelinopathy:
-repeated mechanical pressure and myelin gets damaged
-carpal tunnel
Traumatic Axonopathy:
-crush injury or fracture
-can regrow if schwann and myelin remain (1mm/day)
Severance:
-poor prognosis
-wallerian degeneration within 3-5dy
319
Polyneuropathy
-symmetric involvement
-distal to proximal distribution
Small fibers:
-pain, temp, numb loss
Large fibers:
-ataxia, proprioception loss
320
Guillain-Barre Syndrome
-acute inflammatory demyelinating polyradiculoneuropathy
-occurs after viral infection
-motor issues
-can recover
321
Spinal Levels Traveling Caudally
-L2-S5
322
Medial Dorsal Rootlets
-Ia and AB for fine touch and proprioception
323
Lateral Dorsal Rootlets
-AGamma and c fibers for pain and temp
324
Propriospinal Tract
-only in SC
-surround grey matter
325
Tract Cells
Long axon cells
326
Clark's Nucleus
- T1-L3
-proprioceptive info to cerebellum
327
Substantia Gelatinosa
-glial and small nerve cells
-spinothalamic
328
Lateral Horn
-T1-L2
-cell bodies of pregangilonic SNS neurons
329
Preganglionic PNS Cell Bodies
-S2-S4
330
Epidural Space
-L3-L4
331
Order of Spinal Arteries
-Anterior Spinal Artery
-Segmental A.
-Segmental Marginal A
-Radicular A.
332
Mmt of SC
-stretches 10% with flexion
-none for Cauda
333
Jendrassik's Maneuver
-changes descending input to alter motor function
334
Central Pattern Generators
-Rhythmic activity patters generated by central circuits without external cues
-locomotion, swimming, breathing, swallowing, urinating
335
Stepping Pattern Generators
-type of GPG for walking without cortical output
-flexor-extensor activation using proprioceptive information
-has to be activated
336
Withdrawal Reflex
-remove noxious input by activating remaining LE to prevent falling
-crossed extension reflex
337
Reciprocal Inhibition
-inhibits activated of antagonist while turning on agonist
338
Recurrent Inhibition
-inhibit agonist and synergist muscles to turn on antagonist
-Renshaw cells
339
SC Control of Bladder and Bowel
-afferent into needed
-T11-L2 and S2-S4
Frontal Cortex: tells pons to empty OR corticospinal tract to contract PF muscles
Pons: Sends signals to sacral cord center to contract bladder
Sacral Cord: signals parasympathetic neurons to contract bladder and relax sphincters
340
SC Control of Sexual Function
Psychogenic processes: L1-L2
Reflexogenic Processes: S2-S4
Pudenal: L1-L2 and S2:S4 for orgasm
Injuries
-Above T12: loss of erection and genital sensation, reflexive erections
-L2-S2 intact circuits: normal function, no sensation
-S2-S4 circuit lesion: nothing
341
Segmental SC Injuries
-dermatomal or myotomal patters
342
Vertical Tract Impairments
-ipsi/contra deficits below lesion
343
Anterior Cord Syndrome
-A. Spinal Artery issue
-Paralysis, analgesia, loss of discriminative sensation, loss of temp below lesion
-Keep proprioception and light touch (DCML)
344
Central Cord Syndrome
-trauma induced
Small Lesion: pain and nociception impaired at level of lesion
Large Lesion: pain and nociception impaired at level of lesion AND UE motor issues
345
Brown-Sequard (Hemicord) Syndrome
Ipsilateral segment:
-paralysis and analgesia of everything
Ipsilateral Below:
-Paralysis and loss of proprioception and light touch
Contralateral Below:
-nociceptive and temp impaired
346
Cauda Equina Syndrome
-sensation impaired, pain, LE paralysis, bowel/bladder
-no hyperreflexia
347
Tethered Cord Syndrome
- stretch injury, scar tissue
-LE, bowel/bladder, spine issues
Ant. Cauda equina: LMN
Excessive stretch: UMN
348
Spinal Shock
-24h-3wks
-all reflexes, function and autonomic regulation lost
-end with return of anal reflexes
349
Post-Traumatic SC Injury
-hyperexcitability and hyperreflexia
-more sensation
-poor thermoregulation
-orthostatic hypotension
-dysreflexia
350
SC Bowel/Bladder Dysfunction
S2-S4: flaccid a-reflexive bladder
Above S2-S4: hyperreflexive bladder
-reflex emptying or spasms that cause urine to backflow into kidneys
351
SC Injury and Sexual
