Illusory self-motion (vection) may be inhibited by hypobaric hypoxia

Area of Science:

• Human perception research
• Altitude physiology
• Neuroscience

Background:

• Previous studies indicate altitude affects human perception.
• This research investigates the impact of high altitude on illusory self-motion, known as vection.

Purpose of the Study:

• To determine if higher altitudes inhibit vection.
• To quantify the effect of hypobaric hypoxia on vection strength.

Main Methods:

• Vection strength was measured under normal and high-altitude conditions.
• High altitude was simulated in a climatic chamber to 13,123 ft (4000 m) using hypobaric hypoxia.
• Optic flow stimuli were used to induce vection.

Main Results:

• Vection strength (latency, duration, magnitude) was significantly reduced at high altitude.
• Vection decreased by 14.6% under hypoxic conditions.
• Blood oxygen saturation (Spo2) decreased by 16.7%.

Conclusions:

• High altitude conditions inhibit vection.
• Findings suggest pilots should be aware of altered self-motion perception at altitude for flight safety.