Skip to main content
Fig. 4 | Journal of NeuroEngineering and Rehabilitation

Fig. 4

From: Discriminability of multiple cutaneous and proprioceptive hand percepts evoked by intraneural stimulation with Utah slanted electrode arrays in human amputees

Fig. 4

Intensity discrimination trials. Figure depicts the location of electrodes which evoked different hand sensations, as well as a confusion matrix showing the discrimination performance, and the overall accuracy relative to chance. Full descriptions of the percepts are presented next to the image of the hand and are abbreviated to the bold word in the confusion matrix. Confusion matrices are square, such that the correct answers lie along the diagonal. Asterisks over the bar plot indicates statistical significance with regards to the aggregate data (primary outcome measure). Asterisks overlaid on the confusion matrix indicate statistical significance with regards to an individual condition (secondard outcome measure with limited statistical power; p = 0.08 for 35 Hz and 70 Hz conditions). Subject S5 discriminated between four percept intensities, evoked by stimulation of a single median-nerve-USEA electrode at three different frequencies (35 Hz, 70 Hz, 100 Hz) or sham (no stimulation). The evoked sensory percept was described as ‘tingle’ on all four fingertips. The subject successfully classified these different intensities in 13/20 trials (p < 0.0005, binomial test). * = p < 0.05, ** = p < 0.01, *** = p < 0.001, **** = p < 0.0001; binomial test

Back to article page