Final Exam Lagniappe Flashcards
(157 cards)
1
Q
Bilateral connections between what two structures allow for the pupillary light reflex?
A
Pretectal area and Edinger-Westphal nuclei (Parasympathetic nucleus of oculomotor nerve)
2
Q
What structure is responsible for most of the eyes refraction?
A
Cornea
3
Q
What is phototransduction?
A
The process by which light is converted into electrical signals
4
Q
How does the lens of the eye accommodate for nearby objects?
A
It changes shape and can provide extra focusing power
5
Q
Photoreceptors have ______ membrane potentials.
A
Graded
6
Q
What are the only retinal cells that fire action potentials?
A
Ganglion cells
7
Q
What are the only sources of output from the retina going to the optic nerve?
A
Ganglion Cells
8
Q
In which layer of the retina does phototransduction take place?
A
The inner neuronal layer
9
Q
Ganglion cells synapse with _______ transmitting visual perception.
A
The optic nerve
10
Q
The Meyer’s loop synapses in which part of the visual cortex? What part of the visual field does it supply?
A
The lingula / lower bank
Carries information from the top half of the visual field
11
Q
What is the advantage of having the primary visual cortex retinotopically organized?
A
It allows the brain to process visual information in a way that reflects the layout of the visual field
12
Q
Describe the dorsal and ventral stream
A
Dorsal stream - goes to the parieto-occipital cortex. Also called the “action stream.” used to direct movement
Ventral stream - goes to the occipito-temporal cortex. Also called the perception stream because the info is used to recognize visual objects
13
Q
What is the function of saccades?
A
Allows us to:
-Scan visual field quickly
-focus on the most significant things
14
Q
What structure coordinates the horizontal and vertical gaze centers to synchronize eye movements?
A
Medial longitudinal fasciculus
15
Q
What is the pinna?
A
Visible portion of the ear, forms a funnel for sound waves to come in
16
Q
What separates the outer and inner ear?
A
Tympanic membrane
17
Q
Ossicles transfer movements of the tympanic membrane to movement of the ______.
A
Oval window
18
Q
What nerve innervates the tensor tympani? What about the stapedius?
A
Tensor tympani = CN V3 (mandibular branch of trigeminal)
Stapedius = CN VII
19
Q
Name the structures that make up the vestibular apparatus
A
-Semicircular canals
-Utricle
-Saccule
20
Q
Name the structures that make up the auditory apparatus
A
Just the cochlea
21
Q
Damage to cranial nerve V or VII would lead to contra or ipsi lateral hearing loss?
A
Ipsilateral
22
Q
What are the ossicles? Which one connects to the oval window?
A
-Malleus
-Incus
-Stapes
Bottom part of the stapes is called the footplate, and it connects to the oval window. This is what transmits vibrations to the cochlea!
23
Q
What are the ossicles important for?
A
Sound force amplification. Air pressure by itself is not enough to vibrate the cochlea!
24
Q
What are the two parts of the inner ear?
A
-Auditory apparatus
-Vestibular apparatus
25
What are the three chambers of the cochlea?
-Scala vestibuli
-Scala media
-Scala tympani
26
The organ of cortis is between what two chambers of the cochlea? What structure does the organ of cortis sit on?
It is between the media and tympani chambers.
It sits on top of the basilar membrane
27
What parts of the brain is in charge of sound localization?
Superior olives + primary auditory cortex
28
The Wernicke's area is located just posterior to what?
The primary auditory cortex.
29
Which is more superficial, the primary or secondary auditory cortex?
The secondary auditory cortex
30
After leaving the cochlear nuclei, what three structures does auditory information travel to?
-Medial geniculate body (of the thalamus)
-Inferior colliculus
-Reticular formation
31
Finish the path way.
Organ of corti -> Cochlear nuclei -> medial geniculate body -> __________ -> results in conscious hearing
Primary auditory cortex
32
What components make up the central vestibular system?
-Vestibular nuclei
-Motor pathways
-Cerebellum
33
What components make up the peripheral vestibular system?
-Semicircular canals
-Otoliths
34
If a lesion to CN VIII happens outside of the internal auditory meatus, will it result in central or peripheral type deficits?
Peripheral
35
What is the sensory organ in the ampulla?
Crista. It has the support and hair cells that detect movement
36
What are the four vestibular nuclei? What two tracts are they linked with?
1. Lateral (Delter's)
2. Medial
3. Inferior (Spinal)
4. Superior
Corticospinal and reticulospinal tracts.
37
When there are vestibular disorders, the _______ is essential for adaptations in the postural and balance systems.
Vestibulocerebellum
38
What three descending pathways originate in the vestibular nuclei?
1. Vestibulospinal tract (goes to LMN's to help w/ balance and posture)
2. Vestibuloreticular pathway (goes to RF to help with autonomic functions like alertness)
3. Vestibulocolic pathway (Goes to cervical spinal cord to help controls muscles in head and neck)
39
Which cranial nerve does the vestibulocolic pathway go to?
The CN XI nucleus
Affects the cervical muscle posture control
40
What are the three ascending pathways from the vestibular nuclei?
1. Vestibulothalamocortical pathways
2. Vestibulocerebellar pathways (goes to flocculonodular lobe and helps to fine tune movements)
3. Medial longitudinal fasciculus (synapses with CN 3,4,6 and helps to coordinate eye movements and gaze + VOR.)
41
Basic outline of vestibular pathway
1st order - Vestibular ganglion located in inner ear, near the cochlea
2nd order - Vestibular nuclei in brainstem (pons + medulla)
Note: descending axons from the 2nd order neurons make up the vestibulospinal tract (VST)
42
What is the primary output/function of the vestibular cerebral cortex?
Perception of head orientation
43
______ and ______ systems are tightly linked for postural control and eye movements.
Vestibular; visual
44
Vestibular and auditory systems are tightly linked due to _________ and sharing the same ______.
Geography; cranial nerve.
45
What is neuroplasticity?
Ability of neurons to change:
-their function
-amount and types of neurotransmitters produced
-their structure
46
What are the 3 mechanisms of neuroplasticity?
1. Habituation/sensitization
2. Experience-dependent plasticity; learning and memory
3. Recovery or maladaptation after injury
47
What are the types of non-declarative or implicit memory?
1. Non-associative learning
2. Associative learning
3. Procedural
48
Non-associative learning
A change in response to a stimulus due to repeated exposure to that stimulus, without any association with a reward or punishment.
Two simplest forms are habituation and sensitization.
49
Associative learning
Learning to predict relationships or associate stimuli with other things. Basically just classical and operant conditioning.
Classical conditioning = relationship of one stimulus to another
Operant conditioning = Relationship of one's behavior to a consequence
50
What is procedural learning?
Learning tasks that can be performed automatically without attention or conscious thought.
51
What presynaptic changes cause short-term habituation?
Reduction of excitatory neurotransmitter release
52
What types of conditions can habituation be used to treat?
-Vertigo
-Pain in residual limb post amputation
-Tactile defensiveness
-Tinnitus
53
Sensitization alters the conductance of what? What does this allow for?
It alters the conductance of K+, which creates more time for action potentials to happen, which means more neurotransmitters can be released
54
People with lesions to bilateral medial temporal lobe have difficulty with what?
Remembering factual knowledge
55
Long term potentiation is similar to ______, and long term depression is similar to _____.
Sensitization; habituation
56
What are the three mechanisms of long term potentiation?
-Associativity
-Cooperativity
-Specificity
57
Why are parallel pathways in motor learning important?
They aid in efficiency and redundancy. This is especially important when someone is injured, there will be multiple pathways to accomplish tasks if one gets damaged.
58
What is another name for declarative memory?
Explicit memory
59
What is the function of the lateral prefrontal cortex pertaining to memory?
It has voluntary control over medial temporal lobe in processing and organizing info for storage
60
What makes up procedural memory?
-Learned skills or habits
-Reasoning and logic
-Perceptual skills
61
What aspects of memory do the MMSE and MOCA test for?
-Encoding/registration to immediate recall
-Attention/working memory
-Recent memory (few minutes to short term memory)
-Remote memory (long term memory)
62
What is emotional lability / labile effect?
Uncontrolled laughing or crying which may or may not be related to actual emotions
63
What are the 3 phases of voluntary movement, and what brain structure are they associated with?
1. Target identification - posterior parietal cortex
2. Planning of action - premotor areas of frontal cortex
3. Execution of actions - primary motor cortex
64
What role is the cerebellum most known for?
Feedback role
65
What does the cerebellum monitor?
Errors in performance
66
Where does the cerebellum receive information from, and what does it act on?
Receives info from the somatosensory cortex
Acts on the brain stem and cortical motor areas which then act on the spinal cord
67
Where does the basal ganglia receive input from?
All cortical areas and projects, primarily to areas of the frontal cortex
68
What role is the basal ganglia most known for?
Feedforward role (the feedback is still present in the basal ganglia loops)
69
Ultimately all interneurons ________.
Converge on the motor neurons that innervate skeletal muscles.
70
What is the difference between positive and negative plasticity?
Positive plasticity is the capacity to recover, grow, and change.
Negative plasticity is when the brain undergoes detrimental changes, like learned non-use or excessive compensatory movements. This can happen if a person is not pushed to make beneficial changes and stays in the same habits/routines.
71
What is recovery?
The re-acquisition of movement skills that were lost due to injury
72
How can pre-injury exercise be helpful for recovery?
Exercise induced neuroplasticity and/or angiogenesis
73
Where is the reactivation of silent or weak areas likely to occur in after an injury?
The penumbra
74
What is the penumbra?
The area that surrounds the affected ischemic tissue in the brain during a stroke.
Considered to be at a high risk for death, but can be saved if meds are taken at the right time.
75
What is Diaschisis?
An area of the brain that has been impacted by brain damage even though it is not geographically close to where the actual injury happened.
76
How can diaschisis be reversed?
Normalizing blood flow and metabolism after the injury has been stabilized
77
What are the stages of recovery after a brain injury?
1. Rescue and salvage
2. Repair and recovery
3. Maintenance
78
_________ days of skilled training causes changes in cortical motor maps.
12
79
Unskilled training does not cause neuroplasticity, but it does cause _______.
Circulatory changes in the brain
80
What drugs can be used to facilitate neuroplasticity?
-Amphetamines
-Clonidine
81
What should aggressive therapy treatments emphasize early on to increase positive functional outcomes?
Skill acquisition
82
What are forced-use activities?
Forcing a patient to use their affected limbs/structures.
Ex. Having a patient stand on their affected leg.
83
Compensatory motor behaviors may be the reason why ______.
Motor deficits remain after an injury.
Basically if a person learns and uses compensation movements, they don't actually target the affected muscles and may have those deficits permanently.
84
________ is insufficient to drive changes in the motor cortex.
Simple repetitive use.
Need to have motor skill acquisition to cause changes!
85
Cortical reorganization is associated with increases in ________.
Synapse number
86
What does the nature of reorganization in neuroplasticity depend on?
The specific motor experience the patient is having
87
What three things are needed to design a skill-based intervention?
1. Include the patient when making goals
2. Increase the patient's resources or reduce their impairments
3. Use practice to create and sustain new movement patterns
88
In the context of practice, what is contextual interference?
Doing things in between reps of the exercise.
89
What are some benefits of mental practice/rehearsal?
-Primes the brain for motor learning
-Useful for complex motor skill learning
90
What are the general principles for explicit learning?
Early stage - verbalize the key aspects of the movement and learn each part separately
Late stage - Reduce cognitive engagement, and group everything together to practice the movement as a whole
Optimal - to have goal-directed movement that is automatic
91
When is explicit learning helpful in skill acquisition?
In the early stages
92
According to Dr. Szot, what are the three pathways we care about clincally?
Lateral corticospinal tract
Dorsal Column-Medial Lemniscus
Anterior/Lateral Spinothalamic tract
93
A stroke to the superior devision of the MCA will result damage or deficits to what areas?
-Somatosensory processing
-Face and arms
-Broca's area
94
Which artery is most commonly affected by a stroke? Why?
The MCA
It is the biggest and supplies the most area, so chances are when a stroke happens it will affect it. It also has lots of little areas where clots can get stuck
95
A stroke to the inferior devision of the MCA will result damage or deficits to what areas?
-Wernicke's area
-Auditory centers
Basically motor is spared, just may not be able to communicate that well
96
Contralateral body and facial weakness is almost always a ______.
Brainstem issue/lesion
97
How will UMN facial weakness present?
Only the lower part of the face is affected because the upper face gets innervation from UMN on both sides of the brain
Ex. if you have a left stroke, only the bottom right part of your face will be affected because the top right still has innervation from the other UMN
98
What type of arteries assist the anterior and posterior spinal arteries at each level?
Segmental, anterior/posterior medullary arteries
99
Describe the 3 sensory neuron pathway, including where the DRG is, where info enters/crosses in SC.
1st neuron brings info from periphery to CNS (SC or brainstem)
2nd neuron bring info from SC or brainstem or thalamus
3rd neuron thalamus to somatosensory cortex
100
Describe where the medial and lateral corticospinal tracts run through the brainstem and spinal cord.
Midbrain – cerebral peduncle
Pons – ant pontine fiber bundles
Medulla – pyramids and cross to posterior lateral SC or stays medial anterior
101
Name the parts of the goal-directed behavior loop.
-Lateral prefrontal cortex
-caudate
-globus pallidus internus
-thalamus
102
Which structures form the lentiform nucleus?
-Putamen
-Globus pallidus
103
Which neurotransmitters are impt for BG function, for inputs and outputs?
Inputs: Ach (exc), dopamine (exc or inhib), glutamate (exc), serotonin (inhib)
Outputs: gaba (inhib)
104
What are the 2 types of glial cells that support the CNS?
Astrocytes and oligdendrocytes
105
How is acetylcholine used or what does it do?
Skeletal muscles:
-All neurons that synapse with skeletal muscles use Ach to elicit fast-acting effects on muscle membranes.
-It is excitatory neurotransmitter found in neuromuscular junctions to promote muscle contractions.
-Blocking Ach receptors causes weakness, fatigue, or paralysis.
-Myasthenia gravis destroys Ach receptors.
Autonomic nervous system:
-Slows HR
-Constricts pupils
-Increases smooth muscle contractions and digestive processes
Brain:
-Arousal, pleasure, cognitive function
-Acts as slow neuromodulator in control of movement and attention
-Implicated in nicotine addiction and Alzheimer’s disease
106
Which ion triggers the movement of neurotransmitter vesicles in the pre-synaptic terminal for synaptic transmission? Which type of gait is opened for this ion?
Calcium, voltage gated channels
107
Superior cerebellar peduncle
Mostly efferents
-Projecting to motor nuclei of thalamus, relaying signal to UMN in primary and premotor cortices
-Projecting to red nucleus
-Afferents from ant spinocerebellar tract
108
Middle cerebellar peduncle
All afferents - motor
-Projections arise from contralateral pontine nuclei from cerebral cortex and superior
109
Inferior cerebellar peduncle
afferents and efferents
-Afferents arise from vestibular apparatus/nuclei, SC, inf olivary nucleus
-Efferents project to vestibulospinal and reticulospinal tracts
110
What do purkinje cells do?
Inhibit cerebellar and vestibular nuclei
111
Explain double crossing of anterior spinocerebellar tract.
-Single neuron of anterior spinocerebellar tract begins in TL gray matter, crosses and travels up contralateral ant spinocerebellar tract to the midbrain
-Then tract divides with most crossing at midbrain and entering contralateral superior CP – double cross
-Rest stays ipsilateral entering ipsilateral superior CP
-Each cerebellar hemisphere gets input from both sides of lower body – automatic coordinated LE mvmts
112
Where is the vestibular cortex?
Parieto-insular cortex within posterior end of lateral fissure
113
Which part of the cortex receives info from the primary and secondary somatosensory cortices and visual system and is critical for integration of sensory/motor output?
Posterior parietal cortex
114
Which of the motor cortices is responsible for execution and planning as well as anticipatory postural adjustments?
Premotor cortex (lateral)
115
What forms the tectum of the midbrain?
Pretectal area, inf and sup colliculi
116
Which arteries supply the brainstem?
Midbrain
-Posterior cerebral artery
-Midbrain branches of basilar artery
Pons
-Basilar
-AICA
Medulla
-Anterior spinal artery
-PICA
117
What are the 4 signs of brainstem dysfunction?
-dysphagia
-dysarthria
-diplopia
-dysmetria
118
When does a human embryo transition into a fetus?
8 weeks
119
When does the human neural tube develop?
18-26 days
120
Name a cognitive ability that tends to be preserved as a person ages over time.
Vocabulary, comprehension
121
How do light receptors in the eyes transmit information to neurons?
Phototransduction
122
Describe the visual streams – where they go and what they processes.
Ventral
–occipitotemporal cortex
–form, high spatial resolution, visual acuity (perception)
Dorsal
–parietooccipital cortex
–motion, high temporal resolution (action)
123
Describe mechanoelectrical transduction that occurs when sound waves hit the eardrum.
1. Sound waves hit tympanic membrane, causing
2. Ossicles to move, causing
3. Membrane at opening to cochlea to move/vibrate, causing
4. Fluid in cochlea to move, causing
5. Basilar membrane and embedded hair cells to vibrate, causing
6. Hair cells to bend against attached and immobile tectorial membrane, causing
7. Hair cells to depolarize and activate cochlear n endings
124
Which spinal cord levels have the sympathetic ganglia ?
T1-L2,3
125
Where are the parasympathetic ganglia located?
-Brainstem
-S2-4
126
Name 3 things that occur when sympathetic system is activated when scared?
-Vasodilation to active muscles (skeletal and cardiac)
-Vasoconstriction to gut and skin
-BP, HR, blood glucose increase, bronchi dilate
127
How do voluntary mvmts differ from reflexive mvmts?
-Motor systems can use different strategies in different circumstances to achieve same end.
-Effectiveness of voluntary movements improves with experience.
-External stimulus can, but does not need to, precede voluntary movement.
128
Describe learned non-use phenomenon.
-happens when a patient stops using a limb, even though they have the ability to do so
-often due to a prior negative experience or the tendency to rely on their stronger side
129
What are the synaptic changes after injury?
1. Recovery of synaptic effectiveness
-Resolution of edema compressing on axon allows resumption of normal cell function and synthesis/transport of neurotransmitters
2. Denervation hypersensitivity
-Increased post-synaptic receptors available to accept neurotransmitters released from neighboring neurons
3. Synaptic hypereffectiveness
-When some presynaptic terminals are damaged, remaining post-synaptic branches receive all the neurotransmitters that would normally be shared
4. Unmasking/disinhibition of silent synapses
130
Which 3 sensory systems need to work well together for normal movement and balance?
Visual, somatosensory, vestibular
131
What are the components of the sensory system, starting from the stimulus?
-stimulus
-receptor into action potential
-conduction over pathway to CNS
-translation in CNS (receives, integrates info, may prepare response)
132
Which 3 things impact speed of information processing in sensory system?
Axon diameter, amount of axon myelination, # synapses
133
What do muscle spindles respond to?
Muscle stretch
134
Explain how golgi tendon orgains can inhibit or activate its own muscle.
Afferent signal from GTO inhibits activity of MN and results in muscle relaxation (via neg feedback mechanism – autogenic inhibition) OR activates MN of its own muscle and its synergists via + feedback, depending on responses of spindles, cutaneous and joint receptors, and descending pathways
135
What are the 2 types of lower motor neurons?
Alpha and gamma
136
Describe clasp knife type of spasticity
Initially a large amount of resistance followed by a sharp decrease in resistance when going through ROM
137
What brain structures surround the lateral ventricles?
Caudate, thalamus, corpus callosum
138
What is the abnormality of circulation where arteries connect to abnormal vessels rather than capillaries to veins, making a big tangle of blood that doesn’t circulate appropriately?
Arteriovenous Malformation
139
Describe the blood brain barrier.
-specialized barrier between capillary endothelium of CNS and extracellular space.
-Its permeability is less than regular capillaries so large molecules can’t enter
-Beneficial to prevent lots of pathogens from entering CNS
-However, prevents certain drugs and protein antibodies from entering, too.
-Is absent in areas that sample the blood or secrete into the blood (Parts of hypothalamus and other areas close to 3rd/4th ventricles)
140
Which artery supplies the thalamus?
Deep branches of posterior cerebral artery
141
Which brain areas are activated during perception of pain?
Cingulate gyrus, insula
142
What brainstem areas inhibit pain?
-periaqueductal gray in midbrain
-locus coeruleus in medulla
-rostral ventromedial medulla (raphe nuclei in reticular formation)
143
What are some examples of primary pain in chronic pain sydnromes?
-Fibromyalgia
-CRPS
-nonspecific LBP
-migraines
144
Which type of memory is in the lateral prefrontal cortex, temporoparietal cortex and the white matter tracts that connect them?
working
145
Which motor area is closest to Broca’s area?
Lateral premotor
146
Which structure connects Broca’s and Wernicke’s areas?
Arcuate fasiculus
147
How are language abilities different between the R/L hemispheres?
-L comprehension and production of language
-R prosody, tone of voice
148
Which part/s of the brainstem is the reticular formation in?
All of them.
RF of midbrain and upper pons is continuous with certain nuclei of diencephalon rostrally to have a conscious state in the forebrain
-Rostral reticular formation and related structures
RF of pons and medulla is continuous with intermediate zone of SC caudally for motor, reflex and autonomic functions
-Caudal reticular formation and related structures
149
17 What are the levels of consciousness?
-alertness
-attention
-awareness
150
Which part of the brain produces fear/disgust, interprets social signals, and is impt for decision making?
Amygdala
151
When we have a stress response, which chemical is released by the adrenal medulla to increase our HR, BP, etc.?
epinephrine
152
What is the term for when someone laughs or cries inappropriately and/or uncontrolled?
Labile/lability
153
What provides input to the vestibular nuclei in addition to the vestibular apparatus?
-cerebellum
-contralateral vestibular nuclei
-visual system
-somatosensory system
154
Describe the vestibular ocular reflex.
Head moves and eyes move in opposite direction to stay fixed on a target
155
Where is the olfactory cortex?
-Medial temporal lobe (amygdala, parahippocampal gyrus, uncus)
-insula
156
20 Where do CNs 2 and 3 synapse for the pupillary light reflex
-Midbrain
-pretectal area
-parasympathetic nucleus of CN 3
157
Which body parts do ventral rami supply?
-Ant and lat body
-limbs
-muscles
-skin
