Discrimination of Spatial and Temporal Parameters in Electrocutaneous Stimulation
The effects of training on a person's ability to perceive, interpret and utilize information presented via the tactile sense were examined by using a dual-channel electrocutaneous tracking approach. The electrocutaneous code studied was linear pulse rate encoding of information. The stimulus had a pulse width of 200 μs and a pulse rate between 2 and 50 pulsed per second. Three tracking tasks-visual tracking, onedimensional electrocutaneous tracking and two-dimensional electrocutaneous tracking-were performed by 20 subjects during eight to nine daily training sessions. The effects of this training regimen were found to be highly significant for both electrocutaneous tracking tasks (p<0.00005). The overall average improvement between successive training sessions was 21.6% for one-dimensional electrocutaneous tracking and 22.9% for two-dimensional electrocutaneous tracking. Furthermore, the rate of improvement was fastest during the initial training sessions with a slower rate of improvement seen in most subjects beginning with their fifth session. The cumulative effects of training were also reflected in the lesser amounts of practice and review required by the subjects with each succeeding test session. Results from this study can be used to estimate the amount and rate of improvement that one can expect using a typical training program for tactile sensory aids.