NEU 409 Exam 2 Flashcards

1
Q

The Meninges:

The name of the three layers in order

A

3-layered membrane that surrounds the delicate brain (also surrounds spinal cord)

Dura Mater – outermost brain/spinal cord membrane just under skull bones

Arachnoid Mater – membrane found under dura mater, is the middle layer

Pia Mater – membrane under Arachnoid Mater and separated from it by CSF, inner/deepest layer

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2
Q

Blood Brain Barrier

A

Helps maintain stable environment for brain
Separates neurons from some blood borne substances

3 Parts:
tight junctions between capillary endothelial cells
continuous endothelial cell basement membrane
astrocytes (neuroglia) wrapped around the endothelial cell

Functions
Selective barrier
What passes by diffusion:
Small non- polar molecules (O2, CO2)
Lipid (fat) soluble substances - alcohol, steroids, nicotine, anesthetics, opioids
What passes using facilitated diffusion with “help”(transporters)
Glucose, amino acids, fatty acids

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3
Q

Circle of Willis feeds the brain oxygenated blood through:

CIRCLE OF WILLIS: where all arteries converge
anastomosis:

A

Anterior cerebral artery - Carotid arteries

Middle cerebral artery

Posterior cerebral artery - Vertebral arteries

A blockage in one area of the circle still allows blood to run other ways into the cortex (anastomosis), subjective differences.

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4
Q

Anterior areas are supplied by Carotid System - splits into four parts

A

1.Internal Carotid Artery (ICA - splits into four parts ABCD): ranges off the aorta, courses up one on each side along the lateral portions of the neck. Most important for speech as its branches supply major speech & language areas. Enters the middle of the brain and branches off into 4 branches:

A. Middle Carotid/Cerebral Artery (MCA): branches laterally & supplies most of the lateral portions (posterior part of the frontal lobe) of the cerebrum and deep structures of frontal and parietal lobes, part of medial temporal lobe, internal capsule, part of basal ganglia

B. Anterior Cerebral Artery (ACA): moves anteriorly to the frontal lobe, supplies medial portion of the cerebral hemispheres, superior portion of the frontal & parietal lobes, ant. 4/5 of corpus callosum, basal ganglia (caudate head & putamen). Left & right ACA are connected to each other by the Anterior Comm. artery (AC)

C. Anterior Choroidal : Supplies optic tract, cerebral peduncle; lateral geniculate body (part of visual pathway), and portions of internal capsule - (non cortical arteries)

D. Ophthalmic branch: supplies orbit and surrounding tissue; muscles and bulb of the eye - (non cortical arteries)

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5
Q

Posterior areas are supplied by BLANK

Split into three parts

A

Posterior areas are supplied by Vertebrobasilar system

Arise from the subclavian arteries & ascends through upper cervical vertebrae. They enter skull through Foramen Magnum and continue along ventrolateral surface of Medulla - occipital lobe

Split into three parts:
1. Posterior cerebral artery
2. Basilar artery
3. Vertebral artery

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6
Q

Posterior communicating artery

A

part of the internal carotid system connecting the two systems

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7
Q

Gyrus
Sulcus
Central sulcus/fissure
Lateral sulcus/fissure
Longitudinal fissure
Language center
Corpus callosum
Superior longitudinal fasciculus
Arcuate fasciculus

A

Gyrus (raised mountain surface bumps)

Sulcus (deep grooves or valleys)

Central sulcus/fissure = Fissure of Rolando - frontal and parietal lobe

Lateral sulcus/fissure = Sylvian Fissure - serves to separate the temporal lobe from the frontal and parietal lobes

Longitudinal fissure = connects left and right hemisphere

Language center is left hemisphere

Corpus callosum: connect the left and right cerebral hemispheres.

Superior longitudinal fasciculus (anterior to posterior areas connected)

Arcuate fasciculus (frontal temporal connections; connect Broca’s and Wernicke’s area)

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8
Q

Lobes of the Brain:

Frontal lobe
Parietal lobe
Occipital lobe
Temporal lobe

A

Frontal lobe - reasoning, planning, motor movement

Parietal lobe - sensory perception, & interpretation

Occipital lobe - vision - posterior artery

Temporal lobe - memory, receptive language
Language posterior superior temporal lobe

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9
Q

Frontal Lobe: Prefrontal Cortex

A

Occupies BA 9, 10, 11, 46, 47

Executive control, personality, decision making, and social behavior (Phineas Gage)
19th century case of Phineas Gage and his prefrontal cortex damage taught much about the functioning of this area - working on railroad and had a nail through head and his whole personality changed completely but not major affected areas
Functionally involved with cognition (executive control), personality, decision making, and social behavior

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10
Q

Frontal Lobe: Broca’s area - left hemisphere

A

Occupies BA 44 and 45
BA 45: Interpretation of language (syntax) and planning/programming of verbal responses
BA 44: Coordination of speech organs for language production
Paul Broca, through observations of Tan, one of first to associate BA 44, 45 with speech production
Impairment to this area may lead to Broca’s aphasia (language production impaired)

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11
Q

Frontal Lobe: Premotor Cortex

A

Occupies BA 6
Involved in selecting and planning of motor movements including speech
Close relationship to BA 44
Supplementary motor area (SMA) located at top of BA 6 and involved in sequencing and “turning on” motor plans

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12
Q

Frontal Lobe: Primary Motor Cortex

A

Occupies BA 4
Sends motor plans developed in BA 6 to the muscles for them to act (e.g., speech muscles)
BA 4 has been mapped to form a homunculus or “little man”
Upper motor neurons
Voluntary movement

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13
Q

Parietal Lobe: Primary Sensory Cortex

A

Occupies BA 1, 2, and 3
Processes somatosensory information
Processes somatosensory information such as:
Vibration
Proprioception
Touch
Astereognosis
Homunculus present

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14
Q

Parietal Lobe: Angular Gyrus

A

Occupies BA 39
Involved in reading and math abilities
Damage can lead to alexia and acalculia
May also be involved in understanding metaphors and our sense of embodiment
Damage can lead to outer body experiences (OBEs)
Damage can lead to Gerstmann syndrome—agraphia, alexia, finger agnosia (unable to ID fingers), right/left disorientation

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15
Q

Parietal Lobe: Supramarginal Gyrus

A

Occupies BA 40
Involved in phonological system; stores auditory representations of phonemes (auditory images)
Closely related to the angular gyrus (BA 39)
Helps us sound out words
Damage can result in phonological dyslexia, difficulty reading new and nonwords

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16
Q

Occipital Lobe: Visual Cortices

A

Occupies BA 17, 18, and 19
Where information from eyes is received and processed
Two streams of vision:
Dorsal stream the where of vision - analyzes motion and spatial relationships - (18, 19, 7, and 39?)
Ventral stream the what of vision - analyzes forms, colors, and faces - (18, 19, and 37)

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17
Q

Temporal Lobe: Primary Auditory Cortex

A

Occupies BA 41 and 42 a.k.a., Heschl’s gyrus
Receives auditory information from the ears via CN VIII
Sylivan fissure front and back
Occupies BA 41 and 42 (42 is the secondary auditory cortex, but 41/42 usually discussed as a unit called the primary auditory cortex)
a.k.a., Heschl’s gyrus
Initial cortical region that receives auditory information from the ears via CN VIII8 and the auditory pathway
Processes sound intensity and frequency
Organized by tones (topographically arranged)
Primary Auditory Cortex: Topographic Organization

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18
Q

Temporal Lobe: Wernicke’s Area

A

Occupies BA 22
Meaning of auditory information
Named after Karl Wernicke
Involved in attaching meaning to auditory information
Damage can result in Wernicke’s aphasia, characterized by verbal jargon and a lack of understanding others’ speech
Artery attacked is middle cerebral artery
What’s happening to you - don’t understand language - don’t understand what someone is saying
Speech production and compression (old model)
Conduction aphasia
Brocas is movements - can understand

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19
Q

Parts of diencephalon: left hemisphere - Diencephalon consists of 4 parts:

Located

Brain stem

A

thalamus, epithalamus, subthalamus, hypothalamus

Located superior to the brainstem (specifically to the medulla) and inferiorly to the cortex (telencephalon)

Brain stem: midbrain, pons, medulla
Midbrain = most superior portion
Pons = middle portion
Medulla = lowest portion

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20
Q

Thalamus:

A

Thalamus: Left and right sides of thalamus connected at medial nucleus
A relay station
Sits above brainstem
“Gateway” to cerebral cortex
Functions:
Relays sensory information (except smell)
Perception of pain, temperature, & touch
Helps to maintain cortical arousal, attention, & sleep/wake cycle
Indirectly involved in motor function through fibers into basal ganglia
Routes sensory information to the cortex (except olfaction/smell)

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21
Q

Hypothalamus

A

A regulator for the body
Pituitary gland
Functions:
Autonomic nervous system control
Metabolism
Water balance
Sleep/wake mechanism
Body temperature
Food intake regulation
Secondary sex characteristics
Connects nervous system to endocrine (hormone) system via the pituitary gland
Controls metabolism, food intake, body temperature, emotion
Important role in maintaining homeostasis in the body (even keel)

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22
Q

Epithalamus

A

Connects limbic system to:
Forebrain and Other parts of brain

Parts:
Pineal gland – produces melatonin (regulates sleep/wake)
Habenula- olfactory reflexes (trigger hunger/salivation, gag)
Stria medullaris- connects habenula with limbic system

Pineal gland calcification
Associated with decreased melatonin production
Sleep disorders–association not clear
Associated with some degenerative diseases (like Alzheimer’s)
Melatonin may serve as a neuroprotectant
Mechanism not well understood, but possibly similar to bone formation
Possibly related to age BUT, not everyone shows calcification

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23
Q

Subthalamus

A

Lies below the thalamus
Connects basal ganglia to motor cortex,
thus more related to basal ganglia than thalamus
Damage can result in hemiballism
Involved in selection of actions and impulse control

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24
Q

Ventricles: fluid-filled spaces in brain
Brain contains 4 ventricles:

A

Right lateral ventricle
Left lateral ventricle
Third ventricle
Fourth ventricle

Each ventricle has a choroid plexus structure that produces cerebrospinal fluid

25
Q

Cerebrospinal Fluid (CSF)

A

Produced by choroid plexus
1 located in each ventricle
Modified ependymal cells with tight junctions (barrier between blood and CSF)

CSF found in:
Brain ventricles
Arachnoid space
Brain
Spinal cord

Functions:
Protection
Buoyancy
Removes waste
Transports nutrients and hormones

26
Q

Functions of Cerebellum

A

Helps in planning, monitoring, and correction of motor movement using sensory feedback
Coordinates fine motor activity.
Monitor head and body position.
Participates in learning new motor skills
Cerebellar damage is ipsilateral (same side) to the affected side!
Can be stroke in cerebellum in that artery
Artery supplied to cerebellum vertebral basilar system - posterior cerebral artery

27
Q

Testing the Cerebellum

A

Finger to nose test
Diadochokinesia test (pa-ta-ka)
Uncoordinated, sloppy movement may indicate cerebellar damage

28
Q

Cerebellum Damage Symptoms

Ataxia:
Dysmetria:
Dysdiadochokinesia:
Nystagmus:
Ataxic Dysarthria:
Hypotonia:

A

Ataxia: Discoordinated clumsy movements

Dysmetria: over or undershooting touching a mark

Dysdiadochokinesia: Inability to perform rapid alternating
movements of hand or mouth

Nystagmus: Fast involuntary eye movements either side to side or up and down

Ataxic Dysarthria: Slurred or scanning (broken into syllables) speech

Hypotonia: Reduced muscle tone and reflexes; muscles tire

29
Q

Brainstem Functions:

Brainstem disorders: Pons

A

Regulates major life functions (e.g., heart beat, respiration).
Mediates head and neck reflexes (e.g., gag) via cranial nerves
Regulates alertness and wakefulness.

Brainstem disorders: Pons
Locked-in syndrome
Quadriplegia
Cranial nerve paralysis (except for eye movements)
Diving Bell & the Butterfly

30
Q

On, On, On They Traveled
And Found Voldermort
Guarding Very Ancient Horcruxes

A

I. Olfactory Nerve
II. Optic Nerve
III. Oculomotor Nerve
IV. Trochlear Nerve
V. Trigeminal Nerve
VI. Abducens Nerve
VII. Facial Nerve
VIII. Vestibulocochlear Nerve
IX. Glossopharyngeal Nerve
X. Vagus(wandering nerve) Nerve
XI. Spinal Accessory Nerve
XII. Hypoglossal Nerve (7 and 9 is only tongue sensation)

31
Q

I. Olfactory Nerve
Origin
Functional category
Function(s)
Problem(s)

A

Origin = olfactory bulb
Functional category = special sensory
Function(s) = smell
Problem(s) = anosmia (loss of smell first symptoms in alzheimerizer)

32
Q

II. Optic Nerve
Origin
Functional category
Function(s)
Problem(s)

A

Origin = thalamus
Functional category = special sensory
Function(s) = vision
Problem(s) = visual disturbances; loss of vision

33
Q

III. Oculomotor Nerve - eye
Origin
Functional category
Function(s)
Problem(s)

A

Origin = midbrain
Functional category = motor & parasympathetic
Function(s) =
motor: moves eyes up/down, in/out; upper eyelid - side to side
parasympathetic: pupil constrictor
Problem(s) = loss of pupillary light reflex; ptosis (droopy eyelid)

34
Q

IV. Trochlear Nerve - eye
Origin
Functional category
Function(s)
Problem(s)

A

Origin = midbrain
Functional category = motor
Function(s) = moves eyes in & down
Problem(s) = diplopia (double vision); nystagmus (repetitive movements); difficulty moving eyes in & down

35
Q

V. Trigeminal Nerve - 3 types maxillary, ophthalmic, mandibular
Origin
Functional category
Function(s)
Problem(s)

A

Origin = pons
Functional category = Sensory & Motor
Function(s) =
sensory: touch, pain, temperature, vibration for face, mouth, anterior 2/3 of tongue
motor: chewing muscles
Problem(s) = loss of above sensations; difficulty chewing; abnormal jaw-jerk reflex

36
Q

VI. Abducens Nerve
Origin
Functional category
Function(s)
Problem(s)

A

Origin = pons
Functional category = motor
Function(s) = rotates eyes out
Problem(s) = eye rotates in (strabismus) & diplopia; nystagmus

37
Q

VII. Facial Nerve
Origin
Functional category
Function(s)
Problem(s)

A

Origin = pons
Functional category = motor, sensory, special sensory, parasympathetic
Function(s) =
motor: muscles of face, some eyelid muscles
sensory: sensation near ears
special sensory: taste in ant. 2/3 of tongue
parasympathetic: salivary glands
Problem(s) = facial paralysis; taste loss

38
Q

VIII. Vestibulocochlear Nerve
Origin
Functional category
Function(s)
Problem(s)

A

a.k.a., auditory nerve
Origin = pons/medulla junction
Functional category = special sensory
Function(s) = hearing & balance
Problem(s) = hearing loss; balance problems

39
Q

IX. Glossopharyngeal Nerve
Origin
Functional category
Function(s)
Problem(s)

A

Origin = pons/medulla junction
Functional category = motor, parasympathetic, sensory, special sensory
Function(s) =
motor: pharyngeal movement
parasympathetic: parotid gland (salivation)
sensory: middle ear, pharynx, post. 1/3 of tongue
special sensory: taste on post. 1/3 of tongue
Problem(s) = absent gag & swallow reflex; loss of taste; loss of pharyngeal movement

40
Q

X. Vagus(wandering nerve) Nerve
Origin
Functional category
Function(s)
Problem(s)

A

Origin = medulla
Functional category = motor, parasympathetic, sensory, special sensory
Function(s) =
motor: pharyngeal & laryngeal muscles
parasympathetic: heart, lungs; digestive tract; blood pressure
sensory: pharynx
special sensory: taste from epiglottis & pharynx
Problem(s) = absent gag & swallow reflex; loss of velar movement; loss of voice

41
Q

XI. Spinal Accessory Nerve
Origin
Functional category
Function(s)
Problem(s)

A

Origin = medulla, spinal cord
Functional category = motor
Function(s) = neck & shoulder muscles
Problem(s) = droopy shoulder; movement of neck

42
Q

XII. Hypoglossal Nerve (7 and 9 is only tongue sensation)
Origin
Functional category
Function(s)
Problem(s)

A

Origin = medulla
Functional category = motor
Function(s) = muscles of tongue
Problem(s) = loss of tongue movement; tongue fasciculations, tongue atrophy

43
Q

Spinal Nerves vs Cranial Nerves

A

Spinal nerves all are mixed (sensorimotor)
Cranial nerves that are Sensory only – CN I, II (CN I & II not in brainstem!), VIII
Cranial nerves that are Motor only – CN III, IV, VI, XI, XII
Cranial nerves that are Mixed (Both-sensorimotor) - CN V, VII, IX, X

Location of Cranial Nerves
Most nuclei are in the brainstem (CN I & II are not)
Midbrain – CN III & IV, part of CN V
Pons – CN V, VI, VII, VIII
Medulla – part of CN V, VII, & VIII; in addition CN IX, X, XI, XII exit from here

44
Q

gray vs white

Ascending tracts
Descending tracts

Dorsal ramus:
Ventral ramus:
Spinal nerve:
Dorsal root:
Ventral root:

A

gray inside for cell bodies and white outside) - gray is cell body and axon - inner structure gray butterfly

Ascending tracts - sensory
Dorsal columns: fasciculus gracilis and fasciculus cuneatus → and spinothalamic tract and spinoreticular tract

Descending tracts - motor
Lateral corticospinal tract

Dorsal ramus: Sensory/motor from/to dorsal (back) of body
Ventral ramus: Sensory/motor from/to anterior (front) of body
Spinal nerve: Mixed nerve Sensory/motor
Dorsal root: Sensory info from body GSA, GVA fibers
Ventral root: Motor info to body GSE, GVE fibers

45
Q

Three Neuron Sequence (sensory only): three neuron sequence -

Ascending Pathways (Sensory): anterolateral column - spinothalamic tract stops in thalamus which is huge sensory organ

Crude Touch and pressure:

Pain and temp:

Discriminative(fine,light,precise) touch, vibration, and proprioception(awareness of body part or joints in space:

A

Crude Touch and pressure: (anterior spinothalamic)
Crude touch receptors
Afferent dorsal sensory root
1st order neuron ipsilateral comes in - from right arm right dorsal root
2nd order neuron crosses over to contralateral side
To thalamus in brain

Pain and temp: (lateral spinothalamic) - threatening immediately go to opposite side
Pain/temp receptors
Afferent dorsal sensory root - synapse in dorsal horn
1st order neuron ipsilateral
2nd order neuron crosses over to contralateral side
To thalamus in brain
3rd order primary somatosensory cortex

Discriminative(fine,light,precise) touch, vibration, and proprioception(awareness of body part or joints in space: (dorsal columns cross medulla)
Discriminative touch, vibration, and proprioception receptor
Afferent dorsal sensory root
1st order neuron ipsilateral
To medulla - no 2nd order neuron yet
2nd order neuron crosses over to contralateral side after lower medulla
Synapse in medulla

46
Q

Descending Pathways (Motor) - Lateral Corticospinal Tract - right motor cortex is left side of body
Upper & Lower Motor Neurons (motor only)

A

Muscle
Lower motor neurons
Spinal cord
Two neuron sequence
Brain
Upper motor neurons
Primary motor cortex
Lateral Corticospinal Tract (Voluntary Motor Movement) - two steps
Start in primary motor cortex if grab with left side will do it with right side
Spinal cord
Medulla
Motor cortex
Steps: from motor cortex medulla to muscle: upper motor neuron cross upper motor neuron, efferent ventral motor root, muscle
Motor cortex ipsilateral - medulla contralateral

47
Q

Pathway: Lateral corticospinal Tract

Pathway: Dorsal (posterior) column- Medial Lemniscal pathway

Pathway: Anterolateral pathway (Spinothalamic tract)

A

Pathway: Lateral corticospinal Tract → Function: Motor

Pathway: Dorsal (posterior) column- Medial Lemniscal pathway → Function: Vibration, joint position, fine (discriminative) touch

Pathway: Anterolateral pathway (Spinothalamic tract) → Function: Pain, temperature, crude touch, pressure

48
Q

What Is a Neurological Exam?

Overview of the Neurological Exam

The Neurological Exam

A

A systematic examination of the nervous system performed by a neurologist
Purposes:
Identify abnormalities in the nervous system
Differentiate CNS from PNS problems

  1. The Interview
  2. The Physical Exam
  3. The Neurological Exam
  4. Laboratory Tests

The Neurological Exam
Mental State Evaluation (includes language, memory, attention)
Cranial Nerves Evaluation
Motor System Evaluation (posture, limb movement)
Reflex Testing
Sensory System Evaluation
Equilibrium Evaluation (coordination, balance; walking, DDK rates)

49
Q

Akinesia:

Bradykinesia:

Athetosis:

Rigidity:

Chorea (Gk. for “dance”):

Ballism:

Myoclonus:

Tremor:

Fasciculations:

A

Bradykinesia: slowed movements

Akinesia: without movement

Rigidity: Stiff or tight muscles that resist passive movement to a limb, Leg pipe also called
Example: A relaxed joint will resist being bent or straightened.

Chorea (Gk. for “dance”): quick, involuntary movements of the hands and/or feet that have a dance-like quality

Athetosis: slow, twisting, involuntary movements of the hands and/or feet

Ballism: Quick, involuntary flinging of a limb
When it occurs on just one side of the body, it is called hemiballismus.

Myoclonus: Sudden, involuntary muscle jerks
Example: hiccups

Tremor: = rhythmic shaking
Intention tremor = rhythmic shaking that occurs when trying to do something voluntarily
Resting tremor = rhythmic shaking that occurs while hand is at rest, but disappears when intentionally using hand
Pill-rolling tremor = associated with Parkinson’s disease; appear to be rolling something with thumb and first two fingers

Fasciculations: Muscle twitches
When occurring in the tongue, it has the appearance of worms or snakes quivering in a bag.

50
Q

Basal Ganglia Structures

A

Corpus striatum – caudate nucleus + lentiform nucleus deep within each cerebral hemisphere

Lentiform nucleus – consists of several segments that form the putamen + globus pallidus

Striatum – caudate nucleus + putamen
Inhibits globus pallidus + substantia nigra

a.k.a., Corpus Striatum
Parts:
Globus pallidus
Putamen
Caudate nucleus
(Substantia nigra) - Part of midbrain
(Subthalamic nucleus) - Part of diencephalon

51
Q

Basal Ganglia Circuitry

A

Set of interconnected loops that inhibit or facilitate movement (each separate function)
Four anatomical loops (circuits)
First, largest central loop transmits sensory motor impulses to striatum, globus pallidus, & thalamus (sensory motor integration-voice/auditory feedback)
Other three loops small and act as “subloops” to first basal ganglia loop
BG activities are strongly connected to indirect pathway

52
Q

Functions of Basal Ganglia

A

Lesions result in movement disorders
Regulates posture & muscle tone, adjusts automatic motor movements (follow through during throwing, facial expressions, etc); & suppresses extraneous motor movements when indicated ( hence posture disturbance and altered muscle tone), assists in learning, selection and initiation of movements
No UMNs or LMNs in basal ganglia; therefore, no paralysis occurs with lesions here; however, contralateral control
Lesions result in loss of inhibitory control

Regulates complex motor function such as posture, locomotion, balance, arm swinging
Inhibits function
Coordinates motor behavior
Uses dopamine

53
Q

Basal Ganglia Neurotransmitters

A

Function of basal ganglia depends on balance of several major neurotransmitters (acetylcholine, dopamine, GABA)
Balance is vital to motor regulation
Impairments result in Parkinson’s disease (dopamine & acetylcholine imbalance) or Huntington’s chorea (GABA)

54
Q

Basal Ganglia Impairments

A

Motor activity regulation (Hypokinetic dysarthria affects speech motor control-preparation, maintenance, and switching of motor programs, thus inferencing role of BG in speech motor control)
Mood & personality regulation (psychiatric disorders)
Inappropriate release of movement & loss of inhibitory control
Hypokinetic ( decreased voluntary movement) or Hyperkinetic Dysarthria (increased movement causing involuntary movements)

55
Q

Basal Ganglia Symptoms
Dyskinesias, such as:

A

Bradykinesia
Rigidity (due to increased muscle tone)
Tics
Tremor
Gait issues
Dystonia
Chorea
Athetosis

56
Q

Parkinson Disease (PD)

A

Progressive neurological disease
First described by Dr. James Parkinson in 1817. Also known as the “shaking palsy.”
Caused by degeneration of midbrain’s substantia nigra and loss of dopamine to basal ganglia
Symptoms: muscle rigidity, masked face, micrographia, dyskinesias, resting & pill rolling tremors, shuffling gait, weak voice, dysarthria, flat affect, poor posture, and dysphagia, about 20% will also develop cognitive processing difficulties
Faces of Parkinson’s Disease

Cognitive impairment and dementia in PD
PD is primarily a motor impairment
BUT mild cognitive impairment is very common (NOT the same as dementia)
Dementia is severe loss of cognitive abilities
Across a wide range of cognitive skills
About 20% of PD patients will develop dementia
Why do some progress to dementia and others don’t?
No clear answer to this, but some possibilities:
Other neurotransmitter changes (e.g., acetylcholine)
Medications used to treat PD
Evidence that L-DOPA (and others) are linked to dementia symptoms
BUT, usually rapid onset
PD is more common in older adults
More likely to develop dementia if PD onset after age 60
Risk for dementia increases with age (regardless of PD diagnosis)

57
Q

Parkinson’s Treatment

A

Medications
Levodopa is “gold standard” - Works by replacing dopamine
Pallidotomy: cells in the globus pallidus are selectively destroyed using a heated probe, reducing Parkinsonian symptoms
Deep Brain Stimulation (DBS): surgical insertion of a brain pacemaker that stimulates the basal ganglia, reducing Parkinsonian symptoms

58
Q

Huntington Disease (HD)

A

Progressive, hereditary neurological disease due to degeneration of the basal ganglia
Autosomal dominant pattern of inheritance
If you have the gene, you get the disease
Average onset around 35 years of age
Survival about 10-20 yrs after diagnosis
Symptoms: severe chorea, athetosis, emotional & personality changes, torticollis (twisting of the neck), dysarthria, dysphagia, and dementia.

59
Q

Huntington’s Treatment

A

No cure, medications can help manage disease
Tetrabenazine
Suppress involuntary jerking and writhing movements (chorea)
Serious side effect
Worsening or triggering depression or other psychiatric conditions
Antipsychotic drugs, such as haloperidol (Haldol) and chlorpromazine
Side effect of suppressing movements, can be beneficial in treating chorea
They may worsen involuntary contractions (dystonia) and muscle rigidity