Scientists spin mice to make them motion sick

For those who experience it, motion sickness can be very uncomfortable.  Planes, cars or boats all become grounds for bouts of nausea, vertigo or vomiting.

Scientists are well aware that motion sickness is caused by a ‘conflict’ between your visual system and how the inner ear interprets movement.

But researchers have turned (or should I say spun) to mice to see if they can make sense of exactly which type neurons in the inner ear – known as the vestibular nuclei (VN) – are involved.

To test this, researchers put hungry mice safely inside a tube attached to a spinning device.

After four one-minute trips on the spin machine and five seconds between, the mice were given food to see if they were still hungry.

If they didn’t eat, it was assumed the mice were nauseous and experiencing motion sickness. In the paper, they call this ‘conditional taste avoidance’.

By doing further experiments on the brains of the mice, the team was able to discover that a VN  group called cholecystokinin-expressing neurons plays a central role in motion sickness.

“Previous studies had identified that vesicular glutamate transporter 2 VN (VGLUT2VN) neurons … participate in postural balance and mediate gravitational stress-induced hypolocomotion, hypophagia, and hypothermia,” the researchers write in their paper.

“Here, we confirm that these results show that VGLUT2VN neurons are necessary for the development of motion sickness responses, such as conditioned taste avoidance, in a rotational paradigm in mice.”

The research has been published in PNAS.