Implicit and explicit motor imagery ability after SCI: Moving the elbow makes the difference

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Motor Control

Background:

• Cervical spinal cord injury (SCI) leads to significant upper limb sensorimotor deficits, impacting daily activity and participation.
• Upper limb rehabilitation, potentially including motor imagery (MI), is crucial for recovery, but MI ability post-SCI is not well understood.

Purpose of the Study:

• To investigate implicit and explicit motor imagery (MI) abilities in individuals with C6/C7 cervical spinal cord injury (SCI) compared to controls.
• To determine if MI ability is impaired or preserved following SCI and how it relates to motor deficits.

Main Methods:

• Employed implicit MI tasks (hand laterality, hand orientation judgments, hand-object interaction) and explicit MI tasks (mental chronometry).
• Assessed individuals with C6/C7 SCI and age/gender-matched controls without SCI.

Main Results:

• Implicit MI ability profiles differed between groups, especially in hand orientation judgments (HOJT), correlating with elbow movement deficits in the SCI_C6 group.
• Explicit MI ability profiles were similar across groups, reflecting task familiarity and the inability to perform paralyzed movements in the SCI group.
• Behavioral patterns in implicit MI mirrored existing motor deficits, particularly for tasks involving internal representations of affected body parts.

Conclusions:

• Individuals with long-term SCI utilize embodied cognitive-motor strategies comparable to controls.
• Implicit MI performance differences highlight a direct link between MI ability and the specific motor impairments resulting from SCI.