Motion sickness susceptibility and management at sea

Abstract

Seasickness has been noted from the earliest times. Over 2000 years ago the Greek physician Hippocrates wrote, '… sailing on the sea proves that motion disorders the body …' The word ‘Nausea’ derives from the Greek root word ʼnaus’, hence ʼnautical’ referring to ships. Motion sickness can be provoked by a wide variety of transport environments, including sea, land, air and space and in addition may be induced by some types of visual stimuli. This chapter describes the signs and symptoms of motion sickness, the possible effects on human performance and the different types of provocative stimuli. The mechanism for motion sickness is generally accepted to involve sensory conflict, for which the evidence is reviewed. But what reason or purpose does motion sickness serve a purpose, if any? This ‘why’ of motion sickness is analyzed from both evolutionary and non-functional mal-adaptive theoretical perspectives. Individual differences in susceptibility are great and so predictors for susceptiblity are reviewed. Finally the effectiveness of behavioural and pharmacological countermeasures are evaluated.