Comparison of the effectiveness of biofeedback and relaxation training on hand warming

Finger pulse volume (FPV) biofeedback, relaxation training (RT), and finger temperature (FT) biofeedback were compared for their effectiveness in the alteration of hand temperature (HT). It was hypothesized that the use of FPV, a more direct measure of peripheral blood flow, should be more effective in producing hand warming than the demonstrably latent FT or the less direct RT manipulation. No significant difference in HT alteration was found between the two biofeedback training groups and neither the finger temperature nor finger pulse volume biofeedback groups were more successful than the relaxation training group in the alteration of HT. No significant differences were found in the alteration of FPV among the three groups. A major finding of this study indicates that all groups produced a significant inverted U training function across trials for both FT and FPV. In all cases, rapid learning was demonstrated in the early trials followed by a decline toward baseline in the later trials. These findings are discussed in terms of the role of strategy formation, frustration, saturation, and the limitations of the physiological learning process.