Though still nobody died of a sea sickness, but if you rock to sleep, you can easily spoil to yourself impressions of a holiday, having included in it long movements. Any including those who never faced earlier similar effect can rock to sleep. Children aged up to 12 years, the pregnant women and people having migraine are most subject to a sea sickness.

Sea sickness (the medical name kinetoz, differently – a movement disease) is the term describing a complex of the unpleasant feelings resulting from monotonous fluctuations or a series of the alternating accelerations. The disease of movement can be called an automobile disease, aeroembolism, a riding disease – depending on what type of movement became the motion desease reason. Historically sea rolling therefore also the name "sea sickness" – the most popular was the first most common cause. A motion desease is caused by a mismatch of a control system of position of a body when the nature of the movement simulated by a brain on the basis of visual signals does not correspond to how it is perceived by the components of an inner ear known as a vestibular mechanism.