Factors Affecting Sensory and Motor Learning

Indiana University

Status: Enrolling

Conditions: Basic Science

Treatments: Behavioral: No movement feedback; Behavioral: Movement feedback, target hand; Behavioral: Movement feedback, pointing hand; Behavioral: Direct vision; Behavioral: Explanatory diagram; Behavioral: Attend to the targets

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT05374460

14804

R01NS112367-01A1 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

How participants perceive the position of their own hand in various contexts will be examined. This will include changing the visual display to suggest the hand is in a slightly different position, and asking participants to indicate where they think it is by pointing with their other hand.

Full description

Hand position can be estimated visually, from an image on the retina, and proprioceptively, from sensors in the joints, muscles, and skin. The brain is thought to weight and combine available sensory estimates to form an integrated multisensory estimate. Inherent in this process is the capacity to realign one or both sensory estimates when they become spatially mismatched, as when washing dishes with the hands immersed in water, which refracts light. It is generally assumed that if a person knows about the sensory mismatch somehow, the realignment will not occur. This assumption will be tested in two experiments by giving people this information in different ways. Expt. A: Conscious awareness of the mismatch will be presented in different ways, or absent. Expt. B: Movement error feedback will be presented in different ways, or absent.

Enrollment: 300 estimated patients

Sex: All

Ages: 18 to 45 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Between the ages of 18-45 years old
• Right-handed.
• Covid has been found to have neurological effects in some people, but mostly the effects on sensorimotor control and neurophysiology are unknown. So we will only include individuals who report being free of Covid symptoms in week preceding testing.

Exclusion criteria

• Past or present history of seizure, stroke, any brain or peripheral nerve disease, severe head trauma, or spinal cord surgery.
• Learning or attention conditions such as ADHD.
• Orthopedic or pain conditions, or a history of seriously injured bones, joints or muscles in either arm.
• Lack of normal or corrected-to-normal vision.

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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300 participants in 6 patient groups

Conscious awareness: No information

Sham Comparator group

Description:

Told nothing about the visuo-proprioceptive mismatch. Hand remains hidden beneath mirror that shows visual display. (control)

Treatment:

Behavioral: Attend to the targets

Conscious awareness: Explanatory diagram

Experimental group

Description:

Told in advance about the visuo-proprioceptive mismatch, which will be explained with a diagram. Hand remains hidden.

Treatment:

Behavioral: Explanatory diagram

Conscious awareness: Direct vision of hand

Experimental group

Description:

Foamboard under mirror removed, making the mirror see-through and the hand directly visible.

Treatment:

Behavioral: Direct vision

Movement feedback: No feedback

Sham Comparator group

Description:

No movement feedback (control)

Treatment:

Behavioral: No movement feedback

Movement feedback: Target hand

Experimental group

Description:

Movement feedback about the target hand.

Treatment:

Behavioral: Movement feedback, target hand

Movement feedback: Pointing hand

Experimental group

Description:

Movement feedback about the pointing hand.

Treatment:

Behavioral: Movement feedback, pointing hand