Habituation

Habituation is a process that has been observed in humans and in all other animals which results in the lessening of stimulus over time. An example is pain, which may be very sharp initially, but which becomes more manageable in the course of time. The same phenomenon results in people apparently ignoring the sound of trains regularly passing outside a house or the powerful odors that might be found in the workplace. Habituation is important because otherwise it would be difficult for people to separate the arrival of new stimuli in the environment, which clearly has an impact on security and efficiency. Changes in the level of a stimulus seem to be more important and urgent than their absolute level. This appears to be a learned ability.

Habituation has a particular meaning with respect to drug use. Drugs have a tendency to promote the body's ability to tolerate their effects and, hence, reduce effectiveness. The use of opiates, for example, presents a significant challenge to the body, which in response, can change its chemical configuration to a significant degree and this leads to problems when the drug is withdrawn or otherwise no longer available because the body has converted itself into a system in which the drug is a necessary presence. This is different from the process of addiction, which contains elements of psychological craving quite separate from the physical changes. The use of substances such as caffeine, amphetamines, and sedatives does not customarily involve such a high level of ingestion that physical changes are produced. Other substances, including heroin and alcohol, to a lesser extent, can be used in large enough doses to produce the physical changes and, consequently, may subsequently represent a greater physical risk to the body. However, it is a very complex undertaking to determine to what extent different types of drug affect different types of people and when individuals are at risk of habituation or of addiction. The World Health Organization has since 1964 used the term drug dependence to encompass any condition in which an individual has a strong requirement or need for a drug. In the management of obesity through using pharmaceuticals, it has become apparent that long-term reliance on drugs is generally ineffective without the patient successfully negotiating a variety of changes relating to lifestyle, eating habits, and similar issues.

The same or at least similar combination of factors exists with respect to habituation to tastes of extreme sweetness, saltiness, or other tastes associated with unhealthy food choices. Food technicians expend considerable efforts in creating tastes and food ingredients to attract consumers. It has become clear over recent years in particular that, at least in Western countries, but also other developed and developing countries, consumer tastes have changed to [Page 346]accommodate more extremely pleasing tastes. In the course of time, the process of habituation ensures that what was once a very sweet, very salty, or otherwise stimulating taste becomes less extreme and, hence, less pleasing. Consumers therefore request additional quantities of the desired taste stimulant. When this results in the creation of extra-hot chili dishes, the problem is rarely severe, although desensitization of the taste buds because of excessive spiciness can lead to an intensifying vicious cycle. However, when the process leads to the intensifying desire for sweetness, in particular, this can lead to obesity as more and more sugary products are added to a wider range of products. In combination with intensive marketing of snack foods, of instantly available gratification from fast foods, and the breakdown of the nuclear family as the defining influence upon eating patterns, it has become ever more the case that habituation is promoting obesity in large numbers of people.

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