The authors have previously used self-report semantic differential questionnaires to investigate the effects of combining visual and tactile stimuli in the context of keypads for electronic equipment. Stimuli were prepared that consisted of a range of surface textures printed in transparent ink onto transparent polyester sheets and placed over a range of smileys; images which are inserted into texts and emails to communicate the intended tone of the message. Respondents were asked to complete semantic differential questionnaires after touching the surface textures; after touching the surface textures printed over the smileys; and after looking at; but not touching; the smileys. A principal components analysis was carried out and the loadings in semantic space for each of the textures; smileys; and smiley and texture combinations were calculated (Henson; Choo; Barnes and Childs; 2006).
Although the approach was a productive one; it perhaps required too much time of the respondents. The number of questionnaires that had to be completed almost certainly went beyond the point at which fatigue bias started. It was also not entirely clear how to interpret the results. The tactile and visual stimuli appeared to be combined by weighted averaging; but the choice of stimuli combinations made it difficult to demonstrate this with a level of certainty.
In the experiment reported here; the results of the first semantic differential experiment were used to identify four visual and three tactile stimuli which scored high; medium and low affective responses; and six words which loaded highly on the principal components. Each smiley was then combined with each texture. Respondents were asked to indicate their responses to the combined stimuli on twenty point semantic differential scales against the six words. Analysis of variance was used to determine whether the scores of the stimuli combinations were independent. The results show no significant interaction between smiley visual and surface touch stimuli; showing that people’s combination of effects is first order; perhaps by addition or by weighted averaging.
Keywords: Affective engineering; kansei engineering; information integration