Among the best solutions for seasickness are to watch the horizon, steer the boat, remove as much clothing as comfort allows, make sure there’s fatty food in your stomach, and stand so that your body is oriented in the direction of the boat’s motion.

I know those work anecdotally (for me and others with whom I’ve been on boats). They were explained to me by an ENT dr during a sailboat race to Bermuda about 20 years ago. His explanation was that it was about aligning the different signals the brain gets during motion.

The headband sounds interesting. There’s few things I’ve experienced that are more miserable than extended motion sickness.