Electrotactile perception of scatterplots on the fingertips and abdomen

A comparison of auditory and visual perception of scatterplots showed similar correlation estimation performance in both modalities. The present study replicated this experiment using electrotactile (electrocutaneous) presentation of scatterplots on the fingertips and abdomen, as well as visual presentation. The correlation estimation task resulted in a slightly poorer performance on electrotactile scatterplots (abdomen r = +0.847; fingertip r = +0.723) compared with the previous Flowers auditory displays (r = +0.91). There were similar levels of performance in the visual (control) condition in both the studies (r for both approx. +0.91). The performance in the correlation estimation task was similar across the two electrotactile displays, with perhaps a slight, but not significant (p = 0.077), advantage for the abdominal array. However, a preliminary digit identification task on both displays produced a better performance on the fingertip display (p < 0.05), suggesting that the relative performance of the two displays may be task specific. The present results demonstrate electrotactile perception of complex graphs and provide useful information for improving future versions of tactile displays.