Reactive attachment disorder
The broad theoretical framework for current versions of RAD is attachment theory, based on work conducted from the 1940s to the 1980s by John Bowlby, Mary Ainsworth and René Spitz. Attachment theory is a framework that employs psychological, ethological and evolutionary concepts to explain social behaviors typical of young children. Attachment theory focuses on the tendency of infants or children to "seek proximity" to a "particular attachment figure" (familiar caregiver), in situations of alarm or distress, behavior which appears to have survival value. This is known as a discriminatory or selective attachment. Subsequently, the child begins to use the caregiver as a base of security from which to explore the environment, returning periodically to the familiar person. Attachment is not the same as love and/or affection although they are often associated. Attachment and attachment behaviors tend to develop between the ages of six months and three years. Infants become attached to adults who are sensitive and responsive in social interactions with the infant, and who remain as consistent caregivers for some time. Caregiver responses lead to the development of patterns of attachment, that in turn lead to internal working models which will guide the individual's feelings, thoughts, and expectations in later relationships. For a diagnosis of reactive attachment disorder, the child's history and atypical social behavior must suggest the absence of formation of a discriminatory or selective attachment.
Elaboration likelihood model
The study of attitudes and persuasion began as the central focus of social psychology, featured in the work of psychologists Gordon Allport (1935) and Edward Alsworth Ross (1908). Allport described attitudes as "the most distinctive and indispensable concept in contemporary social psychology". Considerable research was devoted to the study of attitudes and persuasion from the 1930s through the late 1970s. These studies embarked on various relevant issues regarding attitudes and persuasion, such as the consistency between attitudes and behaviors and the processes underlying attitude/behavior correspondence. However, Petty and Cacioppo noticed a major problem facing attitude and persuasion researchers to the effect that there was minimal agreement regarding "if, when, and how the traditional source, message, recipient, and channel variables affected attitude change". Noticing this problem, Petty and Cacioppo developed the elaboration likelihood model as their attempt to account for the differential persistence of communication-induced attitude change. Petty and Cacioppo suggested that different empirical findings and theories on attitude persistence could be viewed as stressing one of two routes to persuasion which they presented in their elaboration likelihood model.