Development of a ground-based sensorimotor disorientation analog to replicate astronaut postflight experience

Area of Science:

• Spaceflight physiology
• Sensorimotor adaptation
• Human factors engineering

Background:

• Spaceflight leads to significant sensorimotor impairments upon return due to adaptation to microgravity.
• Accurate ground-based analogs are crucial for studying and mitigating these postflight effects.

Purpose of the Study:

• To develop and validate a ground-based Sensorimotor Disorientation Analog (SDA) that mimics post-spaceflight sensorimotor challenges.
• To assess the efficacy of different sensory disruption methods in replicating astronaut experiences.

Main Methods:

• Developed an SDA combining galvanic vestibular stimulation (GVS), visual disruption goggles, and a weighted suit.
• Evaluated the SDA with five experienced astronauts, comparing its effects to their actual postflight sensorimotor status.
• Utilized subjective astronaut feedback and objective motor performance measures immediately post-simulated exposure (R+0) and 24 hours later (R+1).

Main Results:

• Galvanic vestibular stimulation (GVS) alone replicated 50-90% of the experienced postflight disorientation.
• A weighted suit further enhanced the analog, replicating an additional 10-40% of the perceived postflight challenges.
• Visual disruption goggles were ineffective in replicating astronauts' experienced visual disturbances and did not significantly impact motor performance.

Conclusions:

• A recommended SDA incorporates GVS and a weighted suit for realistic, transient sensorimotor disruption.
• This analog provides a portable framework for developing spaceflight countermeasures and pre-flight training.
• Future research should focus on refining visual disruption components or alternative methods.