関数解析学
Functional analysis is defined as "the identification of important, controllable, causal functional relationships applicable to a specified set of target behaviors for an individual" and is used for individual evaluation in behavioral activation therapy. In functional analysis, the purpose of the behavior is emphasized in relation to the individual and their environment, i.e. if the behavior is avoidant, rather than the actual topography of the action. Functional analysis is based on the evaluation of an event via the three-term contingency: antecedents, behavior, and consequences. An antecedent is an event that increases the likelihood of a given behavior, the behavior is the individual's response to the antecedent, and the consequence is the reinforcement or lack thereof. Therapists help individuals identify events that typically trigger specific behaviors and the consequences of these behaviors. Then the individual is encouraged to interrupt the three-term contingency pattern for negative consequences by either avoiding the antecedent or changing the behavior. Likewise, individuals are encouraged to seek out antecedents that result in positive reinforcement and to increase the behaviors for which they are positively reinforced.