The Swedish tactile communication aid MiniVib4 conveys the syllabic rhythm via a single transducer. Segmental stimuli like VCV and monosyllabic words would show almost no gain with this type of aid. Another implication is that such an aid will not work well in a speech-training situation because the aid's ability to discriminate between phonemes is limited. The main speech feature conveyed to the hand is the syllabic rhythm for reasons given above. The second channel conveys fricative information for reasons of reliable extraction and high information content.
All results are preliminary in the respect that the amount of training was short.
Therefore all tracking results were measured at a constant error free rates. This rate can otherwise vary between sessions at random, at will or because of bias. It is therefore essential to use the same error free communication rate when comparing tracking results. 2 shows the results of unaided and aided tracking under different conditions for a normal hearing subject with a simulated deafness. The unaided post-tests were added to ensure that learning did not play a major role.