Affect, in psychology, refers to the underlying experience of feeling, emotion, attachment, or mood. History The modern conception of affect developed in the 19th century with Wilhelm Wundt. The word comes from the German Gefühl, meaning "feeling." A number of experiments have been conducted in the study of social and psychological affective preferences (i.e., what people like or dislike). Specific research has been done on preferences, attitudes, impression formation, and decision-making. This research contrasts findings with recognition memory (old-new judgments), allowing researchers to demonstrate reliable distinctions between the two. Affect-based judgments and cognitive processes have been examined with noted differences indicated, and some argue affect and cognition are under the control of separate and partially independent systems that can influence each other in a variety of ways (Zajonc, 1980). Both affect and cognition may constitute independent sources of effects within systems of information processing. Others suggest emotion is a result of an anticipated, experienced, or imagined outcome of an adaptational transaction between organism and environment, therefore cognitive appraisal processes are keys to the development and expression of an emotion (Lazarus, 1982). Dimensions Affective states vary along three principal dimensions: valence, arousal, and motivational intensity. Valence is the subjective spectrum of positive-to-negative evaluation of an experience an individual may have had. Emotional valence refers to the emotion's consequences, emotion-eliciting circumstances, or subjective feelings or attitudes. Arousal is objectively measurable as activation of the sympathetic nervous system, but can also be assessed subjectively via self-report. Motivational intensity refers to the impulsion to act; the strength of an urge to move toward or away from a stimulus and whether or not to interact with said stimulus. Simply moving is not considered approach (or avoidance) motivation It is important to note that arousal is different from motivational intensity. While arousal is a construct that is closely related to motivational intensity, they differ in that motivation necessarily implies action while arousal does not. Affect display Affect is sometimes used to mean affect display, which is "a facial, vocal, or gestural behavior that serves as an indicator of affect" (APA 2006). Cognitive scope In psychology, affect defines the organisms' interaction with stimuli. It can influence the scope of the cognitive processes. Initially, researchers had thought that positive affects broadened the cognitive scope, whereas negative affects narrowed it. Thereafter, evidences suggested that affects high in motivational intensity narrow the cognitive scope, whereas affects low in motivational intensity