Movement Coordination Flashcards
What is the definition of Prehension?
Act of taking hold
Prehension involves both reaching and grasping actions.
What are the two separate motor commands involved in reach and grasp movements?
Reach phase (transport) and grasp phase (aperture formation)
Each command controls a multi-joint movement.
When does the peak hand opening occur in reach and grasp movements?
Occurs during movement deceleration
This is an important aspect of kinematics in these movements.
What is the difference between bimanual movements made to targets of the same distance versus different distances?
3D movement trajectories – hand paths differ
Timing versus spatial characteristics must be considered.
True or False: Maximum aperture occurs at the beginning of the transport phase.
False
Maximum aperture occurs halfway through the deceleration phase.
What leads to increased aperture formation?
- Increasing object size
- When vision is unavailable
- Increasing end point variability
- Increasing speed of transport phase
These factors influence how the hand prepares to grasp.
What are the two types of eye movements?
- Saccades
- Smooth Pursuit
Saccades are rapid movements, while smooth pursuit involves continuous tracking.
What is the duration of a saccadic eye movement?
~30 ms
Saccades precede limb movement.
What is the role of the posterior parietal cortex?
Visuomotor transformations
It is involved in the coordination of eye and arm movements.
In a reaching and pointing task, when does the saccade occur?
Before movement of the head and hand
This illustrates the coordination between eye and limb movements.
What is the impact of cerebellar damage on temporal coordination?
Reduced temporal coordination
This affects the synchronization of movements.
Fill in the blank: The role of the _______ is critical as a coordinating center for eye and arm movements.
cerebellum
The cerebellum integrates sensory input to coordinate movements.
What must you be able to describe regarding reach and grasp movements?
Timing of both phases and timing between both arms during bimanual tasks
Understanding spatial coordination using angle-angle plots is also important.
What happens to velocity records during the maximum grasp aperture?
They are not smooth due to low data sampling rate
This can affect the analysis of movement characteristics.
