L11: Hypokinetic Dysarthria Flashcards
The basal ganglia includes…
the striatum, putamen, globus pallidus, substantia nigra, and subthalamic nuclei
the BG has complex interconnections and loops w the _____ and ____
motor cortex and thalamus
The BG are involved in 5 things…
regulation of muscle tone
scaling the force, amplitude, and duration of movements
adjusting movements to changes in the enviro/context
assisting in the learning, preparation, and initiation of movements
sensorimotor integration processes
depending on which parts of the BG are damaged, the BG disorders can cause ______ or _______
excessive movements (hyperkinetic disorder) or reduced movement (hypokinetic disorder)
in PD or parkinsonism, the movements are mostly…
reduced or hypokinetic
in PD the _____ neurons are destroyed and this causes….. which disrupts…
substania nigra
causes a reduction in the supply of dopamine to the striatum
this disrupts the sensorimotor integration circuits and motor output of the BG
A protein found in the NS, called ______ can start to miss fold and form ____ w/o neurons ….. which …
alpah-synuclein
lewy bodies
which damage the neurons and cause PD to develop
certain regions of the NS such as the _____ are more susceptible to the formation of _____
substantia nigra
lewy bodies (possible link to large number of dendrites and mitochondira in the SN)
the presence of lewy bodies is confirmed by…
postmorterm analysis - work on detecthing from spinal fluid is progressing
PD is thought to involve of combo of
enviro and genetic factors
substantia nigra is important in PD dev, but other structures….
are involved as the disease progresses from presymptomic (prodromal) to later stages
PD = the traditional form of
idiopathic PD
parkinsonism =
showing parkinson like symps (not necessarily idopathic PD)
parkinsonism is caused 89% of the time by…..
67% of it being ____
22% of it being ____
other 3% is ____ and another 3% is ____
degenerative conditions
67% = idiopathic PD
22% = atypical parkinsonism diseases, parkinson plus syndromes (ex. multi system atrophy)
strokes and other conditions (postencephalitis, drugs/toxins)
MPTP a drug …
was first observed in heroin users
will produce parkinsonism in monkeys
ideopathic PD is of ____ etiology, probably…
unknown
prob combo of genetic and enviro factors
Ideopathic PD is ____ - ___% of general population, about ____ % of population over 60 years
0.1-0.2%
2-3%
onset of PD is usually after ____ but some younger, progression is ____ when diagnosed later in life
55 years
faster
IPD is caused by…. which leads to…
loss of dopaminergic cells in sunstantia nigra, which leads to reduced amount of dopamine released in the putamen (striatum)
___% of substantia nigra cells are destroyed before onset of motor symptoms
70-90%
providing IPD patients w replacement for lost _____ significantly reduced symptoms
striatal dopamine
levodopa (L-dopa) is
only about ___% of medication reaches the blood brain barrier
a precursor to dopamine
compound w carbidopa to inhibit breakdown of levadopa in the peripheral blood
5%
_____% of patients will begin to develop periods of dyskinesia (chorea or dystonia) after 5 years of levodopa (eg. peak-dose dyskinesias)
80-90%
after 10 years of levodopa some symptoms such as ____ are hypothesized to become _____ to levodopa
dysarthria
resistant
but recent work in Adam’s lab does not support this
4 main symptoms of parkinsonism (TRAP acronym)
Rest tremor
akinesia
rigidity
loss of postural reflexes
describe rest tremor
4-6 per second
present when limb is fully supported and at rest
reduced or absent during purposeful movement
may be related to abnormal central oscillators or alterations in peripheral feedback loops
not always present in parkinsonism but very common
describe akinesia
reduction in spontaneous movements
movements are reduced in range, force, complexity or speed (slowness = bradykineasia)
(delayed initiation of movement, simple manual tasks are diff and slow)
describe rigidity
an inc resistance to passive movement
approx equal in flexors in extensors
present thru entire range of movement (lead pipe)
cogwheel often present
intermittent inc in resistance over the range of movement
describe loss of postural reflexes
pts do not respond normally to a threat to their posture
pull test causes retropulsion (many steps backward) or falling
in advanced PD this leads to severe disability and bed or wheelchair bound
name 2-3 other symptoms of PD
reduced arm swing during walking
stooped or flexed posture
shuffling gait
motor freezing, i.e. in front of doorways
festination of gait or other movements (rapid & accelerating movements)
mask-like or reduced facial expression
reptilian stare with reduced blinking
micrographia (small writing)
swallowing problems
non-adapting glabellar reflex (forehead tap/eye blink)
cognitive disturbances; typically in later stages (10-30%)
what are the two ways IPD can be diagnosed? (3rd new way?)
based on clinical criteria and neuromotor exam (UPDRS)
autopsy assessment of lewy body levels in BG
new option –> DaT scan
diagnosis of IPD bases on clinical criteria and neuromotor exam (UPDRS) involves…
presence of bradykinesia + rest tremor or rigidity
at least 2 supportive criteria (i.e. response to levodopa, olfactory loss)
absence of exclusion criteria or red flags (i.e. ataxia, vertcial gaze probs, rapid progression of gait, speech, swallow in first 5 years autonomic probs
bradykinesia =
slowness of movement
diagnosis of IPD via autopsy involves
pt must be deceased and brain donated for evaluation
has been used to demonstrate that clinical diagnosis is only about 85% accurate
describe DaT scan (dopamine transporter scan) as an IPD diagnosis tool
imaging procedure (SPECT) and radioactive material to detect dopamine transporters (DaT) on nigro-striatal cells
supportive info (not typically used to diagnose PD) : somtimues used in support of a v mild PD
- can be associated w false negs
- does not distinguish bw PD and other parkinsonism
-NOT being used in canada bc of false negs
how many stages of Parkinsonism?
5
stage 1 of parkinsonism? mean time?
unilateral involvement (eg. tremor and reduced arm swing on one side)
4.5 years
stage 2 of parkinsonism? mean time?
bilateral involvement without posture or balance impairments (eg. bilateral tremor and rigidity)
6.5 years
stage 3 of parkinsonism? mean time?
bilateral involvement and postural instability - mild to moderate impairment
8.5 years
stage 4 of parkinsonism? mean time?
bilateral involvement and postural instability - severe impairment; still able to walk or stand unassisted
11.5 years
stage 5 of parkinsonism? mean time?
wheelchair bound or bedridden unless aided
15 years
the most common method of assessing motor symptoms in PD is the?
how are things rated?
Unified parkinson’s disease rating scale (UPDRS)
0 - 4 point scales with 27 items (4 * 27 = 108 max score) that rate the severity of PD symptoms (tremor, bradykinesia/hypokinesia, rigidity, posture/gait, speech)
quite a bit of _____ in symptoms and rate of progression in PD
heterogeneity
several subtypes of PD have been proposed but none are _____, some are:
universally accepted
tremor dominant vs gait/posture subtypes;
mild motor onset vs motor + non-motor symptom onset subtypes
what are the 5 abnormal sensation and perception features in PD?
- Sense of jaw position (proprioception) abnormal
- Two-point lip and tongue discrimination (touch) abnormal
- Sense of tongue force levels and levels of respiratory effort are abnormal
- Abnormal sense of smell (olfaction) a very early symptom in PD
- Abnormal perception of speech intensity, speech rate, emotional tone of speech, and facial expressions of emotion.
has been hypothesized that there is a causal link bw impaired ______ and motor impairments in PD
_____ has been hypothesized to be linked to an impairment in self-loudness perception
perceptual processes
hypophonia
7 most distinctive features of hypokinetic dysarthria are
monopitch
reduced stress
monoloudness
inappropriate silences
short rushes
rapid rate
reduced loudness level
