Postural motion perception during vestibular stimulation depends on the motion perception threshold in persistent...

Area of Science:

• Neuroscience
• Vestibular System Disorders
• Human Motor Control

Background:

• Persistent postural-perceptual dizziness (PPPD) is characterized by perceived instability exceeding objective sway.
• The impact of vestibular stimulation on postural misperception in PPPD remains unclear.
• Understanding sensory-perceptual integration is crucial for PPPD management.

Purpose of the Study:

• To investigate sensory-perceptual scaling of postural control during vestibular stimulation in PPPD.
• To determine if abnormal sensory-perceptual scaling contributes to unsteadiness during body movements in PPPD.
• To explore the relationship between vestibular motion perception thresholds and postural control in PPPD.

Main Methods:

• Recruited 32 patients with PPPD and 28 healthy controls (HC).
• Assessed objective, perceived, and reproduced postural sway under varying sensory conditions, including binaural galvanic vestibular stimulation (GVS).
• Correlated postural sway with GVS perception thresholds and PPPD-specific questionnaires.

Main Results:

• Patients with PPPD exhibited lower GVS perception thresholds compared to HC.
• PPPD patients showed increased perceived and objective sway on a firm platform.
• Posturo-perceptual ratios during GVS did not differ between groups, indicating preserved scaling.
• Lower vestibular motion detection thresholds in PPPD patients correlated with increased reproduced instability on solid ground.

Conclusions:

• Posturo-perceptual scaling of postural control is largely preserved in PPPD patients during GVS.
• Vestibular stimulation does not inherently destabilize PPPD patients more than HC.
• Low vestibular motion perception thresholds may contribute to instability and misperception in PPPD, informing physical therapy strategies.