RT Journal A1 Freedman RR T1 TEmperature biofeedback for raynaud's syndrome JF JAMA JO JAMA YR 1989 FD November 17 VO 262 IS 19 SP 2681 OP 2681 DO 10.1001/jama.1989.03430190061018 UL http://dx.doi.org/10.1001/jama.1989.03430190061018 AB To the Editor.—  I read with interest your recent article entitled "Behavioral Treatment of Raynaud's Syndrome"1 and thought that recent work on the treatment of idiopathic Raynaud's disease with biofeedback and the mechanisms of this treatment would be relevant. A controlled study comparing finger temperature feedback, finger temperature feedback under mild cold stress, autogenic relaxation, and electromyogram biofeedback found that the first two methods produced reported symptom reductions of 67% and 92%, respectively, at 1-year follow-up, whereas the latter two treatments were ineffective.2 These results were corroborated by ambulatory recordings of finger and ambient temperatures and by laboratory tests of the ability to increase finger temperature voluntarily without feedback. Three-year follow-up data showed that the symptomatic improvement in the two temperature feedback groups was retained.3A series of subsequent studies4 replicated the above findings and demonstrated that elevations in finger temperature were accompanied by increased finger