Lecture 18 Flashcards
briefly explain musician’s dystonia (MD) and its prevalence
affects 2/100 people -> loss of voluntary control of their extensively trained and complex sensorimotor skills
what specific type of musicians does MD affect
keyboard players
what is MD triggered by
fear of failure, overtraining, chronic pain, high demand for precision
what are some factors that predispose someone to MD
higher anxiety levels, later start to training, muscular tension, soft tissue damage, problems with sensorimotor representations
true or false - women are more susceptible to having problems with sensorimotor representations
false - males are more likely
true or false - males are more likely to be diagnosed with MD
true
list the 4 major changes from MD
- reduced motor system inhibition
- altered sensory integration
- impaired sensorimotor integration
- impaired network connectivity
what does EMG recordings demonstrate about reduced inhibition in the motor system
patients with MD have prolonged muscle firing or spillover activation of nearby muscles
where does reduction in inhibition occur in the brain
cortical, subcortical and spinal level
explain the evidence of reduced inhibition at the spinal level
reduced inhibition at antagonist muscle groups involved with co-contraction -> agonist (contractions) and antagonist (relaxing and lengthening)
explain the evidence of reduced inhibition at the cortical level
this can obtained through TMS in both hemispheres -> induced electrical current -> EPSP -> nerve impluse to target organ
- increased difficulty stopping a sequence of actions halfway through the execution
describe the behavioral evidence for altered sensory integration
can be found in the form of difficulty in detecting spatial and temporal separation of subtly presented stimuli
true or false - altered sensory integration is apparent in the somatosensory cortex
true
where is the receptive field of a cortical neuron
area on the skin where tactile stimulation either excites or inhibits a cell
what was the relationship between training and receptive fields in the fingers
training increased number of receptive fields in the distal tips of the phalanges of digits 2,3 and 4
what happens to individuals with impaired sensorimotor integration
people with MD show improvements to fine motor control under experimental manipulations to somatosensory input
true or false - increasing tactile stimulation can lead to improvements in dystonic symptoms
false - increasing stimulation can lead to worse symptoms
what does combining vibrations with TMS do
decrease agonist muscle activity and increase antagonist muscle activity
changes in what circuits implicate abnormal network connectivity
- connecting the basal ganglia and cerebellum
- region in premotor cortex -> transmission of information
- sensorimotor and frontal-parietal areas
what are the 3 ways for MD to be treated
- exercises to increase inhibition of overactive motor groups
- injecting botox to weaken muscles that are overactive
- transcranial direct current stimulation
example how transcranial direct current stimulation is done -> study was done
applied to bilateral motor cortices of pianists -> can increase activation in one hemisphere and decrease activation in the other
what is the difference between anodal and cathodal stimulation
anodal -> increase activation
cathodal -> decrease activation
define neural crosstalk
motor commands can shift from one hemisphere to another via the corpus callosum
regarding the bimanual mirrored finger movements study, what was found
improvements in performance that remained four days after the stimulation -> larger benefits for those who had extreme symptoms