Study sets, textbooks, questions
Upgrade to remove ads
Measurement of Motor Skill Performance
Terms in this set (81)
Measure of time and speed, most frequently used in neuroscience
How is someone a more efficient performer?
They accomplish an action in less time
The interval between the onset of the signal (stimulus) and the initiation of a response (when the movement starts)
How many reaction time tasks are there?
What are the three different reaction time tasks?
1. Simple Reaction Time (SRT)
2. Choice Reaction Time (CRT)
3. Discriminant Reaction Time (DRT) (aka go no- go paradigm
When does someone have a go signal?
When they have a warning signal. The fore period interval between these two stimuli is random for each trial. Thus this prevents anticipation of movement in people
Simple Reaction Time (SRT)
- One stimulus is paired with one response
- 1S1R mapping --> detect a stimulus and plan a movement, might use retinotectal pathway. Often has manual movement
- 200-250ms is a normal reaction time for SRT
Choice Reaction Time (CRT)
- three SR mappings, but can have any number
- This reaction time is greater than a normal reaction (500ms) time because you need to detect a stimulus, the identify it, then select an appropriate response, then move
- Requires a lot more cognitive processing (executive control) = longer reaction time
- ex each light is associated with a different finger use
Discriminant Reaction Time (go no- go)
- Have 3 stimuli, but only one response
- ex, only respond if the red light goes on, if another light goes on, then you don't make a response
- Difficult for someone to withhold response if there is a stimulus
- Must assert high level inhibitory control (dorsal lateral prefrontal cortex)
- This is used a lot to diagnose those with poor impulse/inhibitory control
What is a fractioned reaction time?
A technique where you split up the movement into two different components
What are the two fractioned components of reaction time?
- Period of time between onset of stimulus and beginning of muscle activity
- Measures from muscle (EMG)
- EMG will essentially show nothing, since muscle hasn't been instructed with information to move yet
- 80% of whole reaction time interval should be premotor. This represents stimulus reaction time (upper motor neurone deficit, causes a delay in upper motor processing
- Period of time between onset of muscle activity and observable movement
- Represents time lag in muscle needed to overcome inertia of a limb
- Uses EMG
- It takes time to build up the muscle units to produce enough force to cause a movement = motor reaction time deficit
- Caused by deficit in a lower motor neurone, could make it slower (ex low back compression, affects connection of alpha motor neuron and the muscle fibres
- 20% of whole RT should be a motor
Putting reaction time to practice (track and field)
- The international association of athletic federations criterion for sprint start is 100 msec
- If reaction time is less, then it is considered a false start because they were anticipating the started gun
Is the track and field criterion valid?
No. Athletes are anticipating the starters gun, thus starting the pre motor RT before the gun goes off. Normal reaction time is around 400-500msec, prosaccade reaction time is like 200msec. This is much less inertia than the whole body movement, which makes it easier.
- The interval between the initiation of the response (so an end of the reaction time) to the completion of a movement.
- The movement time varies as a function of the complexity of the movement
- Much easier to significantly improve the movement time with training
- Small window to improve reaction time
- Training for reaction time will not improve movement time and vice versa
Total Response Time (TRT)
- This is the interval that includes reaction time and movement time RT +MT
How can you describe movement?
1. Qualitative description
2. Quantitative level, use movement kinematics
3. Simple finger movement
- Used when slowing film down, looking at frame by frame
- Make verbal descriptions on time lapse photography
Movement Kinematics (quantitative level)
- Branch of kinematics that describe pure motion (how far, how fast)
Displacement: spatial position of the effector (ex arm) during movement
Velocity: rate of change of an objects position (ex arm) with respect to time (first derivative of movement)
Acceleration: change in velocity of an object (ex arm) during a movement (second derivative of movement)
Single finger movement
- The most efficient way to approaching something is not in a linear way (can cause neural deficit), however in a curvature. We never want our hand to obscure the sight, then we can guarantee successful movement
- If it is farther movement, it will go faster. Theres a slight positive skew, so the tail is a bit longer on the right hand side of the curve. This is because when slowing back down, they are using feedback (vision proprioreception) to modify the environment, to make sure the movement is precise and accurate
- Peak acceleration and peak deceleration also increase as a function of displacement
MR: case study
- developed an apraxia due to a large lesion in left posterior lobe
- had to cut a bagel right, but with slight curvature
- MR could not control fluid transition between forward and backward
- As elbow velocity increases, so does the wrist velocity, so this allows for a fluid and smooth movement
- But with more MR, the relationship is completely disjointed, so not able to couple together the wrist and elbow velocity
- MR has a timing coordination movement deficit, so he can no longer time the movement of different muscles, not able to coordinate the movement
- Movement kinematics is able to diagnose the, and then rehab can be changed
- Electrical activity associated with the muscle contraction
- Provides information regarding the temporal and intensity components characteristics of movement
What two types of muscle contraction can electromyography assess?
1. Tonic contraction
2. Phasic contraction
When the muscle is artificially stimulated (ex magnetic impulse)
- Stimulated all extrafusal muscle fibres at the exact same time, so can be very painful
- This is a synchronous pattern of action
EMG for a voluntary contraction
- There are a bunch of little blips, meaning that the muscle fibres are firing at different points of time
- This is an asynchronous pattern of action (not getting information and firing all at the same time)
What is co-contraction?
No longer any reciprocal inhibition, so agonist and antagonist are contracting at the same time, so cannot actually move (biceps and triceps are firing at the same time)
Purpose of measuring brain activity
Provides a measure of when and/or what brain regions activate during movement
What is axonal transmission?
When axon is transmitting info
What methods are best for measuring axonal transmission?
1. Electoencephalography (EEG)
2. Magnetoencephalography (MEG)
What kind of resolution are EEG's and MEG's best at providing?
High temporal resolution
What does high temporal resolution provide?
- A millisecond by millisecond basis so you can see what happens to the brain over a period of time
- Provide colours as symbols for increase or decrease in a axonal transmission
What do warm colours represent in an axonal transmission?
Increase in axonal transmission
What do colder colours represent in an axonal transmission?
Decrease in axonal transmission
What methods are best for measuring spatial resolution?
1. MRI - provide structural scan of brain
2. fMRI - provide a structural scan in addition to a functional scan (so where stuff is happening)W
What do spatial resolution techniques provide?
- Orange colours represent activity associated with the task
- Bad view of temporal lobe, because you can only see a snapshot every few seconds
- The ability to represent separate structures in the brain
What is the most important role of an fMRI?
Measures BOLD signal (blood oxygen level dependency)
- Provides measure of where oxygenated blood is going in the brain
- Since oxygen has red blood cells which contain iron connected to hemoglobin, the resonance imaging is able to track a big magnetic on the fMRI
What is a PET scan?
Positron Emission Tomography
What is the purpose of a PET scan?
Tracks glucose absorption
How does a PET scan work?
- Tags the glucose with a radioactive tracer, then the PET tracks where the glucose is going.
Purpose of PET scan?
- Allows us to see where the brain is taking up more glucose, thus see where the brain is more active
- Used clinically to diagnose neurodegenerative diseases
- Not a technique really used for research because it has poor spatial and temporal resolution
What is TMS?
Transcranial Magnetic Stimulation
How does TMS work?
- Puts a magnetic pulse to the brain to activate neurons randomly
- TMS can be used to create a temporary lesion
Examples of TMS
- Fired stimulation to Brocas area, then the person couldn't speak. Person could still sing though because it is bilaterally represented (not just Brocas area)
What is repetitive TMS?
Clicking a magnetic stimulation multiple times
What happens if you stimulate a temporary lesion in V1?
- This can lead to a particularly blurred out area in your visual field = scotoma
- This will only happen for a second since it is a temporary lesion, but some stroke patients will have a permanent scotoma
Study by Fadiga and TMS
- Did a single pulse of TM, when people performing motor imagery task (so to primary motor cortex)
- Evoked a motor potential (MEP) in a part of the body that is represented by the brain (ex hand portion) this can be measured by EMG of the body part
- Measured corticospinal excitability
What is corticospinal excitability?
How excited neurons are to fire
What did the study by Fadiga and TMS measure?
Measured EMG of a finger muscle, and its MEP. Amplitude of MEP gives direction for corticospinal excitability, so the bigger it is, this means that there is a bigger corticospinal excitability (so how ready they are to move)
One condition apart of the study (FADIGA)
Patients think about extending and bending arm (motor imagery task). Patients apart of the control group saw a bar that got bigger or smaller (visual imagery condition). They applied single TMS to both of these conditions on the hand representation of their right arm
Results of condition in study
They found that in the control group, there was a very small amplitude MEP, which means that the corticospinal system is not very excitable (not ready to contract or make a movement)
In the motor imagery condition, both flexion and extension components had a very large amplitude MEP
When do we have a bigger MEP?
When you think about moving but are not actually moving
Does corticospinal excitability increase or decrease when you think about moving?
Increase because when you decide to get up, the corticospinal neurons are already excited and ready to move. This could be why motor imagery improves a motor skill
Other purposes of Repetitive Transcranial Magnetic Stimulation (rTMS)
Can examine neuroplasticity
Blindness case with rTMS
One person acquired a form of blindness vs another person who had a conginetial form of blindness (so born with it). Applied rTMS to V1 for 10 min, then ask patients if they felt parasthesia (pins and needles sensation) in their fingers and to what extent.
Warm colours = more intense paresthesia
Results of case
The person with congenital blindness has much more parasthesia in their fingers than the person with acquired blindness
What do the results of the blindness study provide evidence for?
V1 has transitioned from visual area to haptic area meaning for tactile sensory information (interprets information coming into the body by the skin). So neural plasticity caused neurons to transition to detect touch information instead of vision, demonstrates neural plasticity
What is the case of CK (creatine kinase)?
24 year old had lesion in right hemisphere which was caused by a hemorrhagic stoke. She had a sensory motor form of a apraxia (able to mimic a movement but couldn't control movement when done with tool)
What is transitive action?
Using a tool to perform an action
What is intransitive gestures?`
What is a monosynaptic connection?
One connection from upper neuron to lower neuron. No immediate spinal connection, which allows for more control for innervation
Do humans use precision or power grasp to get food?
Humans use precision because they have connections to the lateral corticolspinal tract, and animals use the power grasp
What is Heath's study?
Had participants point to a target as quickly as they could. Some were looking at a fixation cross, the target was either in there upper or lower visual field
Target was made so that in the lower visual field, the fixation cross was higher, response was thus faster and more accurate
Supports the idea that there's a vertical visual field asymmetry
(Heaths study) The lower visual field has more .... ?
More neurons that project to motor cortex
What is innervation?
Distribution of nerves to a part of the body
What is innervation ratio?
Number of muscle fibres innervated by a single alpha motor neuron
What is extrafusal fibre? (alpha motor neurons)
Power producing fibre
What is intramural muscle fibre?
Muscle fibres inside of muscle spindles. Innervated by a special system called gamma motor neurons or fusi motor neurons
What is the innervation ratio of obicularis oris?
Under 10 (very low)
What is the innervation ratio for a quad muscle?
Over a 1000
Lower ratio = ?
Fewer motor innervations in each motor unit
What is fusi motor neurons?
Small neurons that innervate intramural muscle fibres and they're responsible for modifying sensitivity of muscle response to dynamic stretch (Tell muscle how sensitive it should be to stretch)
Intrafusal muscle fibres are oriented in parallel with extrafusal fibres
What is fast twitch fatiguable (FF)?
- Highest conduction velocity (100m/s)
- Large fibre diameter, heavily myelinated
- Lots of force, short period of time
- innervates fast twitch muscle fibres
What is fast twitch fatigue resistant (FR)?
- Medium conduction velocity (60m/s)
- Medium fiber diameter
- Innervates slow and fast twitch muscle fibres
What is slow twitch fatigue resistance (SR)?
- Slow conduction velocity (40m/s)
- Small diameter, less myelinated
- Slow twitch muscle fibre
- For endurance athletes
What do the three colours mean in a picture of muscle fibres?
- Darkest = slow twitch because there's more hemoglobin, aerobic, therefore needs lots of oxygen
- Lightest = Fast twitch because it is anaerobic so it doesn't require continuous oxygen
Do pro saccades or antisaccades have a faster reaction time?
Prosaccades because they make fewer directional errors
Study on pro saccades in western movies
Retinotectal pathway can also be used in limb movement for reflexes. Researchers used participants to perform a difference sequence of touch on a paradigm which has three different coloured buttons
Results of study on prosaccades in western movies
The person that sarted first always had finished later than the other. So the person reacting to the others movement had the faster reaction
The person that is innitiating response has to use the whole pathway with antisaccades to plan out the whole movement (executive control, frontal motor structure)
The person that is reacting doesn't have to use executive control, they are in a stimulus driven mode (retinotectal pathway, similar to reflex in pro saccades, much shorter pathway)
- Not a disease, more like a state
- Neurological condition, where people have a blending of two senses (ex experiencing colour when listening to music)
- Could be a cause of increased wiring in the brain that allows sensory information to be linked, or that the extra wiring is always there but inhibition is present to prevent different parts brain to communicate in normal brains
- In synesthetes, there is no inhibition to present sensory connection
How to determine changes in genome that causes Synesthesia?
Look at family tree where synesthesia runs in to determine a specific gene
Could be linkage of high level of movement (ex dancer) and music or colour. This could help them learn the high level movement through synesthesia
Other sets by this creator
Recommended textbook solutions
Advanced Engineering Mathematics
Fundamentals of Engineering Economic Analysis
David Besanko, Mark Shanley, Scott Schaefer
Chemistry for Engineering Students
Lawrence S. Brown, Thomas A. Holme
Process Dynamics and Control
Dale E. Seborg, Duncan A. Mellichamp, Thomas F. Edgar
Other Quizlet sets
Psychology of Coaching Final
Psychology Exam 2
Genetics Counseling and Inheritance