A new nausea model in humans produces mild nausea without electrogastrogram and vasopressin changes

Area of Science:

• Neuroscience
• Human Physiology
• Gastroenterology

Background:

• The optokinetic drum is a standard but clinically limited model for human nausea research.
• Developing accessible experimental models for inducing nausea is crucial for clinical relevance.

Purpose of the Study:

• To create a novel human experimental model for inducing mild nausea.
• To investigate the relationship between mild nausea and electrogastrogram (EGG) activity.
• To explore the connection between mild nausea and plasma vasopressin concentrations.

Main Methods:

• Twenty-one volunteers underwent a vection protocol involving rotating visual stimuli.
• Electrogastrogram (EGG) monitoring, blood draws for vasopressin assay, and symptom rating scales (nausea, dizziness, headache) were employed.
• Subjects also reported motion sickness proneness and anxiety levels.

Main Results:

• Mild to moderate nausea (mean 3.6/10) was induced in 8 subjects.
• Nausea severity correlated with motion sickness history and dizziness, but not anxiety or headache.
• No significant differences in electrogastrogram or vasopressin levels were observed between subjects who developed nausea and those who did not.
• Plasma vasopressin levels showed a high correlation with baseline anxiety, not nausea.

Conclusions:

• A new human vection model effectively induced mild nausea, which was independent of electrogastrogram and vasopressin abnormalities.
• The strong correlation between anxiety and vasopressin suggests vasopressin may not be a direct indicator of nausea.
• Central nausea onset can occur without concurrent electrogastrogram changes, highlighting the complexity of nausea pathways.