Changes in cutaneous sensitivity after prolonged exposure to unpatterned light

Abstract

Changes in cutaneous sensitivity after prolonged exposure to unpatterned light! Ab8tract Ss who were exposed to diffuse, homogeneous illumination for a week showed an increase in tactual acuity and in sensitivity to heat and pain. This cutaneous supersensitivity, however, was not as pronounced as that occurring after a week of darkness. Problem Of the various behavioral effects produced by prolonged exposure to sensory and perceptual deprivation, Qne of the most perplexing is an increase in pain sensitivity (Vernon & McGill, 1961) and in tactual acuity as measured by both a two-point threshold (Doane et al., 1959) and a tactual fusion method (Zubek, 1964). Recently, Zubek et al. (1964) demonstrated that anoverall reduction in the level of visual, auditory, tactualproprioceptive, and social stimulation is not essential for the appearance of this cutaneous supersensitivity. It can occur following visual deprivation alone. In this study, the Ss, who were exposed to a week of darkness, showed a pronounced increase in tactual acuity and in sensitivity to heat and pain. This effect of visual deprivation was uniform. It was shown by all experimental Ss, on all skin areas, and on all cutaneous measures. Furthermore, the effects were still present several days after the termination of darkness. The purpose of the present study is to determine whether similar effects will result from prolonged exposure to diffuse, homogeneous illumination. If this should occur, it will suggest that these cutaneous effects have resulted from an absence of pattern vision rather than an absence of visual stimulation per se.

Short-Term Visual Deprivation Does Not Enhance Passive Tactile Spatial Acuity

“…In contrast to short-term visual deprivation, several studies have reported that prolonged visual deprivation does drive tactile acuity enhancement [5], [6], [27], [28]. Surprisingly, however, Merabet et al [27] found that five days of visual deprivation coupled with Braille training were insufficient to improve participants' performance on the GOT beyond the levels of improvement observed in a non-visually-deprived Braille-trained control group (a significant effect of visual deprivation was found only on a Braille character recognition task, not on the GOT).…”

“…These findings were soon followed by reports that prolonged visual deprivation alone sufficed to improve tactile perception. Zubek et al [5] , [6] demonstrated that seven days of visual deprivation produced tactile acuity enhancement, as assessed by two-point and tactile fusion tasks; the investigators observed facilitatory effects of visual deprivation when participants were completely light deprived, and also (but to a lesser degree) when participants were deprived of patterned vision.…”

Visual Cortex Hyperactivity During Arm Movements in Brain Injured Individuals: Evidence of Compensatory Shifts in Functional Neural Systems

“…Significant increases in auditory and tactile sensitivity in normals after a week of visual deprivation have been demonstrated (1)(2)(3). Furthermore, Feinsod et al (4) demonstrated shorter somatosensory evoked response latencies in blind subjects trained in tactile skills than those in sighted persons, suggesting neural adaptation as a function of training.…”

Changes in critical flicker frequency during prolonged visual deprivation

“…A l-week period of visual deprivation was shown to improve performance in various threshold tasks involving the nondeprived modalities. Thus, performance on tests of heat and pain sensitivity, tactile temporal fusion (Zubek, Flye, & Aftanas, 1964;Zubek, Flye, & Willows, 1964), auditory flutter fusion (Duda & Zubek, 1965;Pangman & Zubek, 1972), and olfactory and gustatory detection (Schutte & Zubek, 1967) improved following visual deprivation. Although there were a few measures which did not show improvement (e.g., gustatory sensitivity to hydrochloric acid and quinine; Schutte & Zubek, 1967), results of this series of experiments show the sensoristatic theory to be a useful predictor of crossmodal deprivation effects.…”