Spatial Factors in Vibrotactile Pattern Perception

The spatial acuity of the skin for pressure stimuli has been explored extensively, but there have been few attempts to study spatial resolution for vibratory stimuli of the type used in tactile aids for sensory disability or to augment communication. Because vibrotactile spatial acuity has never been empirically determined at such sites, pattern perception with these devices might be poorer than it could be if the stimulus parameters that optimize localization were employed. Vibrotactile localization was measured on forearm and abdominal sites used by wearable tactile communication aids. Surprisingly, stimulus frequency did not affect localization on the arm, tested on 8 Os for a given spatial arrangement; both on the arm and trunk (tested with 8 Os), fewer than half of the sites were uniquely identified. Because tactile aids should be usable throughout a person’s life span, especially in the later years, older persons will also be tested in these studies of the spatial aspects of vibrotactile pattern perception.