Somatosensory stimulation improves imagery disorders in neglect

Area of Science:

• Neuroscience
• Cognitive Psychology
• Rehabilitation Medicine

Background:

• Unilateral neglect is a common deficit following right brain damage.
• Mental imagery, involving object and spatial representation, is often impaired in these patients.
• Transcutaneous electrical neural stimulation (TENS) is a non-invasive neuromodulation technique.

Purpose of the Study:

• To investigate the effect of TENS on mental imagery abilities in patients with unilateral neglect.
• To determine if TENS applied to the neck can improve performance on tasks of object and spatial mental representation.

Main Methods:

• Nine patients with right brain damage and unilateral neglect participated.
• Participants completed tasks assessing mental imagery of objects (drawing, shape comparison) and space (describing squares).
• Tasks were performed both with and without transcutaneous electrical neural stimulation (TENS) applied to the left and right sides of the neck.

Main Results:

• TENS applied to the left side of the neck significantly improved performance on object-based mental imagery tasks.
• Left-sided TENS also led to significant improvements in spatial mental imagery tasks.
• No significant effects were observed with right-sided TENS.

Conclusions:

• Left-sided cervical TENS can enhance mental imagery for both objects and space in patients with unilateral neglect.
• These findings suggest TENS may modulate neural systems crucial for mental representation.
• TENS represents a potential non-invasive therapeutic approach for cognitive deficits in brain-injured patients.