The effect of visual stimulation via the eyeglass display and the perception of pain

Hospitalization involves anxiety and pain for many people. Unfamiliar hospital settings various diagnostic and therapeutic procedures and the sight and sounds of medical procedures exacerbate pain and anxiety. By blocking off the anxiety-inducing sights and sounds of the hospital surroundings and creating a pleasant environment an eyeglass display might be able to change the sensation and perception of pain. In this randomized controlled cross-over study 72 healthy university student volunteers were asked to wear a light-weight eyeglass that projected a feeling of watching a 52-inch television screen at 61/2 feet in distance while pain was produced by a modified tourniquet technique. Subjects were randomly assigned to participate in a V-session or B-session first with subsequent cross-over. In a V-session subjects were instructed to wear the eyeglass and watch the soundless display of natural scenery during the inflation. In a B-session the eyeglass that subjects wore would project a static blank screen. During V-sessions there was a significant increase in pain threshold (p < 0.001) and pain tolerance (p < 0.001). The degree of immersion was positively correlated with improvement in pain threshold whereas the anxiety level was negatively correlated with improvement in pain threshold. These findings have implications for using visual stimulation as a positive adjunct to other methods of pain relief and for different pain conditions. This study was considered to be the pioneer use of visual stimulation in the local Chinese community as an adjunct to pain relief.