Prismatic adaptation reduces biased temporal order judgements in spatial neglect

Area of Science:

• Neuroscience
• Cognitive Psychology
• Rehabilitation Medicine

Background:

• Spatial neglect is a common deficit following right hemisphere damage.
• Patients with spatial neglect often exhibit an ipsilesional attentional bias.
• Visuomotor adaptation using optical-wedge prisms has shown promise in reducing spatial neglect symptoms.

Purpose of the Study:

• To investigate if prism adaptation reduces spatial neglect by attenuating the ipsilesional attentional bias.
• To explore the neural mechanisms underlying the therapeutic effects of prism adaptation in spatial neglect.

Main Methods:

• Five patients with right hemisphere damage performed visual temporal order judgments (TOJ) before and after adapting to rightward-deviating prisms.
• The magnitude of ipsilesional attentional bias was measured using the TOJ task.
• Control experiment with healthy participants adapting to leftward or rightward prisms.

Main Results:

• Visuomotor adaptation to rightward prisms significantly reduced the ipsilesional attentional bias in patients.
• Normal participants showed no change in TOJ performance after adapting to either prism type.
• Prism adaptation appears to rebalance attentional distribution in spatial neglect.

Conclusions:

• Prism adaptation is a viable therapeutic strategy for spatial neglect.
• The beneficial effects of prism adaptation are linked to the modulation of attentional bias.
• This research offers insights into attention rebalancing mechanisms in brain-damaged individuals.