habituationhəˌbɪtʃ uˈeɪ ʃən
addiction, dependence, dependance, dependency, habituation (noun)
being abnormally tolerant to and dependent on something that is psychologically or physically habit-forming (especially alcohol or narcotic drugs)
a general accommodation to unchanging environmental conditions
The act of habituating, or accustoming; the state of being habituated.
Habituation is a decrease in response to a stimulus after repeated presentations. As a procedure, habituation is the repeated presentation of an eliciting stimulus that results in the decline of the elicited behavior. This can be rooted from one becoming accustomed to a stimulus to such an extent, that one is simply less responsive or reactive to the stimulus. This process is gradual and is caused after prolonged exposure to the said stimulus. This can include an old ring tone which may grab our attention quicker than a new ring tone to which we are not well-adapted. For example, a medical student finding the shock of treating a cut to decrease after multiple presentations is experiencing the process of habituation. The opposite is the process of sensitization, an increase of the elicited behavior from repeated presentation of a stimulus. There may also be an initial increase followed by a decline of the elicited behavior. Another related phenomenon is stimulus generalization, when habituation occurs in response to other stimuli that are similar to the original stimulus. The opposing process, stimulus discrimination, is when habituation does not occur to other stimuli that are dissimilar to the original stimulus. A progressive decline of a behavior in a habituation procedure may also reflect nonspecific effects such as fatigue, which must be ruled out when the interest is in habituation as a learning process.