researchers, as the subsequent chairs show) believe that expression of emotion is only one aspect of tone of voice. Not to even mention the moral implications of providing someone with a device that uncontrollably broadcasts their emotional state through tone of voice.

We believe that designers can play a valuable role in disability-related design, not only in refining clinically and technically driven solutions, but also in provoking discussion about the very role of assistive technology, a theme explored in Design Meets Disability [ 6]. So Chair No. 2 is not the end of the story.

Chair No. 3. The Offering/Seeking Chair goes beyond emotions. We have reservations about using the phrases “emotional speech” and “expressive speech” interchangeably. Our emotions are just one of the things that we express through tone of voice, and even then, the situation is more complicated: when we try to suppress our emotions but they are still discernable, when we feign an emotion, or when two emotions are combined or even in conflict.

Chair No. 3, the Offering/Seeking Chair, is based not just on the emotions of the speaker, but also around the relationship they have with their conversational partner, the social context in which they find themselves, and their conversational intent. It is built on the work of Nick Campbell, a speech corpora researcher [ 7]. The chair’s interface is a series of six toggle switches: two to register the social relationship between conversational partners; two to reflect the conversational intent of any individual utterance. This leaves two switches to register a total of just four emotional states.

... and challenging existing paradigms

We are interested in understanding more about the relative strengths and weaknesses of this approach when compared with the emotional model. The overall number of tones of voice, and therefore the cognitive overhead, is not too dissimilar. But we are gaining complementary sensitivity at the expense of fine emotional control.

Our interactive prototypes allow each to be
deployed within a conversational context to
assess their effectiveness—not only their clarity
or ambiguity, but also the conversational influ-
ence and creative expression that they afford.
These contexts have to be carefully crafted, given
that the chairs are limited to just four words for
prototyping reasons. There is a secondary con-
trol on the other side of the seat, selecting “no,”
“really,” or “hello” in favor of the default “yes,” all
four chosen for the importance of tone of voice
in their meaning and for their role in engaging
and sustaining conversation. This is not without
precedent in the study of AAC: Some people with
aphasia lose their vocabulary yet nonetheless
manage to influence and direct a conversation [ 8].

[ 6] Pullin, G. Design Meets Disability. Cambridge: The MIT Press, 2009.

[ 7] Campbell, Nick. “Getting to the Heart of the Matter: Speech as the Expression of Affect, Rather Than Just Text or Language.” Language Resources and Evaluation 39, 1 (2005): 109–118.

[ 8] Goodwin, C. “A Competent Speaker Who Can’t Speak: The Social Life of Aphasia.” Journal of Linguistic Anthropology 14, 2 (2004): 151–170.

[ 9] Jones, D. English Phonetics. Cambridge (U.K.): W.H. Heffer, 1936.

[ 10] Kempelen, Wolfgang von. Mechanismus der menschlichen Sprache nebst Beschreibung einer sprechenden Maschine. Vienna: JB Degen, 1791.

[ 11] IDEO. “Social Mobiles.” 2002. http:// www.ideo.com/work/ item/social-mobiles/ [ 12] Standage, T. “Think Before You Talk.” The Economist, January 16, 2003.

September + October 2010