Space motion sickness: incidence, etiology, and countermeasures

Area of Science:

• Space Medicine
• Neuroscience
• Human Physiology

Background:

• Space motion sickness affects 60-80% of astronauts in microgravity and upon return to Earth.
• Symptoms include pallor, nausea, fatigue, and vomiting, impacting astronaut performance.
• Current pharmaceutical treatments often have undesirable side effects.

Purpose of the Study:

• To review the proposed mechanisms behind space motion sickness.
• To highlight the need for further research into its underlying causes.

Main Methods:

• Review of existing hypotheses on space motion sickness.
• Analysis of symptoms and their relation to physiological changes in microgravity.

Main Results:

• Two primary hypotheses are discussed: the fluid shift hypothesis and the sensory conflict hypothesis.
• The fluid shift hypothesis links sickness to cranial fluid shifts and increased intracranial pressure.
• The sensory conflict hypothesis relates sickness to a mismatch in spatial orientation signals.

Conclusions:

• Space motion sickness is a significant challenge for space travel.
• Further research into the mechanisms of space motion sickness is crucial for developing effective, non-pharmacological treatments.