Mood and memory.

This article describes experiments in which happy or sad moods were induced in subjects by hypnotic suggestion to investigate the influence of emotions on memory and thinking. One result was that subjects exhibited mood-state-dependent memory in recall of word lists, personal experiences recorded in a daily diary, and childhood experiences; people recalled a greater percentage of those experiences that were affectively congruent with the mood they were in during recall. Second, emotion powerfully influenced such cognitive processes as free associations, imaginative fantasies, social perceptions, and snap judgments about others' personalities (e.g., angry subjects generated angry associates, told hostile stories, and were prone to find fault with others). Third, when the feeling-tone of a narrative agreed with the reader's emotion, the salience and memorability of events in that narrative were increased. Thus, sad readers attended more to sad material, identified with a sad character from a story, and recalled more about that character. An associative network theory is proposed to account for these several results. In this theory, an emotion serves as a memory unit that can enter into associations with coincident events. Activation of this emotion unit aids retrieval of events associated with it; it also primes emotional themata for use in free association, fantasies, and perceptual categorization. To begin this discussion of the phenomena of statedependent memory let me cite two illustrations. When I was a kid I saw the movie "City Lights" in which Charlie Chaplin plays the little tramp. In one very funny sequence, Charlie saves a drunk from leaping to his death. The drunk turns out to be a millionaire who befriends Charlie, and the two spend the evening together drinking and caThis article was a Distinguished Scientific Contributions Award address given at the meeting of the American Psychological Association, Montreal, September 1980. It is respectfully dedicated to my teachers, Neal E. Miller and Frank A. Logan. I acknowledge the wise collaboration of Stephen Gilligan, Ken Monteiro, and Randy Gellerman in conducting these experiments and the help of the "Bower Industries" research group in interpreting the results. The research was supported by Grant MH-13905 from the National Institute of Mental Health. Requests for reprints should be sent to Gordon H. Bower, Department of Psychology, Stanford University, Stanford, California 94305. rousing. The next day, when sober, the millionaire does not recognize Charlie and even snubs him. Later the millionaire gets drunk again, and when he spots Charlie treats him as his long-lost companion. So the two of them spend another evening together carousing and drinking and then stagger back to the millionaire's mansion to sleep. In the morning, of course, the sober millionaire again does not recognize Charlie, treats him as an intruder, and has the butler kick him out by the seat of his pants. The scene ends with the little tramp telling the camera his opinion of high society and the evils of drunkenness. The second illustration involves a talk I had recently with Bernard Diamond, a forensic psychiatrist who lives in the Bay Area, about a famous criminal case he dealt with—the case of Sirhan Sirhan, the man who assassinated Bobby Kennedy in Los Angeles in 1968 (see Diamond, 1969; also Kaiser, 1970). Interestingly, Sirhan had absolutely no recollection of the actual murder, which occurred in the small kitchen of the Ambassador Hotel where he pumped several bullets into Kennedy. Sirhan carried out the deed in a greatly agitated state and was completely amnesiac with regard to the event. Diamond, called in by Sirhan's attorneys, hypnotized Sirhan and helped him to reconstruct from memory the events of that fateful day. Under hypnosis, as Sirhan became more worked up and excited, he recalled progressively more, the memories tumbling out while his excitement built to a crescendo leading up to the shooting. At that point Sirhan would scream out the death curses, "fire" the shots, and then choke as he reexperienced the Secret Service bodyguard nearly throttling him after he was caught. On different occasions, while in trance, Sirhan was able to recall the crucial events, sometimes speaking, other times recording his recollections in automatic writing, but the recall was always accompanied by great excitement. The curious feature of the case was that material uncovered under hypnosis never became consciously available to Sirhan in his waking state, and he denied that he committed the murder. MoreVol. 36, No. 2, 129-148 Copyright 1981 by the American Psychological Association, Inc. 0003-066X/81/3602-0129S00.75 AMERICAN PSYCHOLOGIST • FEBRUARY 1981 • 129 over, he denied that he had ever been hypnotized by Diamond, denied that it was his own voice on the tape recorder, and denied that it was his handwriting—he alleged that Diamond must have hired an actor or a handwriting specialist to mimic him. Sirhan eventually did accept the theory that he must have killed Bobby Kennedy, rationalizing it as an act of heroism in the cause of Arab nationalism. But his belief was based on "hearsay," much as is my belief that I was born on a Wednesday evening—I must have been there but I sure