In psychology, attitude is a psychological construct, a mental and emotional entity that inheres in, or characterizes a person. They are complex and are an acquired state through experiences. It is an individual's predisposed state of mind regarding a value and it is precipitated through a responsive expression towards oneself, a person, place, thing, or event (the attitude object) which in turn influences the individual's thought and action. Most simply understood attitudes in psychology are the feelings individuals have about themselves and the world. Prominent psychologist Gordon Allport described this latent psychological construct as "the most distinctive and indispensable concept in contemporary social psychology." Attitude can be formed from a person's past and present. Key topics in the study of attitudes include attitude strength, attitude change, consumer behavior, and attitude-behavior relationships.