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In some biofeedback experiments non-contingent, false, or sham feedback has been used in an attempt to control for the placebo and non-specific effects (for example, Finley (1977; Engel and Hansen, 1966)• These studies, however, have used

information has not been systematically manipulated. The process involved in biofeedback is when the information concerning bodily functions is continuously made known to the subject so that unconscious bodily events are brought at least under partial control. The concept of false

biofeedback refers to the manipulation of this information so that the individual is somehow misinformed about his or her bodily events. The subject is thus lead to believe that physiological activity is decreasing or increasing as the case may be. A classical experiment by Valins (1966) using false biofeedback of this kind has been reported

particularly in support of the self attribution theory discussed in the previous section.

Valins (1966) conducted an experiment which was concerned with "some of the cognitive effects of internal events". The objective was to ascertain whether the labelling of

emotional stimuli would be affected by information

concerning internal reactions. Subjects viewed slides of semi nude women while hearing sounds which were allegedly their heart beats. One group of subjects heard their "heart rate" increase to some of the slides and not to others. The control group heard no change to the "heart rate". Using rating scales, Valins found that subjects in the

experimental group rated slides which were associated with increased heart rate more favourably than the other slides. Valins concluded that subjects who were presented with false

biofeedback assumed that they were excited and, therefore, rated the slides as exciting. Therefore, in support of Schachter's (1964) self attribution theory, it was argued that the individual uses external cues such as physiological reactivity to explain and label emotional states.

During the early 1970's, a number of false feedback experiments (Stern, Botto and Herrick, 1972; Decaria, Proctor and Malloy, 1974) generally supported Valins' results supporting the self attribution theory. These studies were almost unanimously rejecting the operant

conditioning model of biofeedback. Thus false feedback has been used to demonstrate the shortcomings of the operant conditioning model and emphasize placebo effects and the self attribution theory.

Recently, however, the self attribution theory has been criticized as a result of renewed interest in the field of false biofeedback and the replication of many of these

experiments including Valins7 original study (Parkinson and Colgan, 1988; Beck, et al 1988). These recent experiments have argued that the Valins effect is due to experimenter demand rather than self attribution. It is argued that given the elements involved in a typical false feedback

experiment, the aim of the experiment is made salient so that the subject may guess what is demanded of him and respond accordingly. Evidence for the experimenter demand

hypothesis comes from studies in which subjects have been given only very brief false feedback (five seconds) which is thought to be too brief a time to search the slides for

cause of the apparent physiological arousal (Barefoot and Straub, 1971)• Here significant feedback effects in terms of subjective reports have been found, suggesting that subjects may be giving high ratings to slides associated with heart rate change only to please the experimenter. Although these results offer criticism on the experimental manipulations reported by Valins and his associates, experimenter demand may not necessarily be the salient feature in all false

feedback studies. For example, some experiments using false biofeedback have found subjective ratings by subjects to be congruent with actual physiological change following false feedback (Shahidi and Powell, 1988). In other words, it has been found that subjects receiving, for example, false heart rate biofeedback suggesting that heart rate is decreasing across a relaxation session, report more relaxation but also show a significantly more decreased heart rate than control subjects receiving no feedback. Furthermore, as pointed out earlier, actual physiological changes have been reported in experiments using placebo effects (Sternbach, 1964). It is difficult to assume that physiological changes are also due to experimenter demand since pleasing the experimenter in effect means denying actual heart rate change and reporting one's state of relaxation as congruent with the direction of false feedback. If there is no experimenter effect there is

no desynchrony between subjective reports and actual heart rate change. Therefore, it may be argued that the

experimenter demand hypothesis may play an important role in some non-contingent biofeedback studies but its significance is very much questionable for the effects observed in most false feedback experiments. Furthermore, false physiological feedback has been used in clinical studies where some

psychological problems such as chronic shyness and speech anxiety have been successfully alleviate (Borkovec, et al 1974)• It seems therefore that if experimenter demands are carefully disguised in false feedback studies, then self attribution seems to be the most likely explanation for the effects observed.