How do task content and interaction mode shape the cognitive and emotional experience?

Since March 2010 when the first iPad was introduced, a great enthusiasm hassurrounded interactive tablets. The use of such multi-touch devices has tremendously increased and can be done for all sorts of purposes (work, leisure and educational activities). Great expectations surround this technology in terms of performances, knowledge acquisition and entertainment abilities. For instance, in the United States of America more than 210 million of tablets are sold each year, and more than 5 million students use tablets in schools for educational tasks. Despite this interest, the need to use gestures to interact with tablets can be experienced has difficult, frustrating and not suited for all kind of tasks. Indeed, if one could assume that using only fingers can be the most practical way to perform an information search task, a former study has showed that it could interfere with students’ performances and user experience (Van der Linden, Debue, Amiel, & van de Leemput, 2014). The purpose of our study is to confirm and precise these outcomes.The study has been realized in a usability laboratory with the participation of 60 university students. Each student was asked to perform information search tasks involving the most commonly used interactions (e.g. right click, left click, zooming, scrolling, encoding) on an online encyclopaedia and randomly assigned between two conditions: (1) tablet condition (finger use) or (2) laptop condition (keyboard and mouse use). The information search tasks were differentiated in function of their difficulty in terms of interaction needed and cognitive demands. Simple interaction tasks were defined as implying mostly left mouse clicks or actions that only require a short finger contact with the touchscreen, and complex interaction tasks were defined as implying right clicks, zooming and encoding commands, or actions that need repeated finger contact actions with the touchscreen. Low and high cognitive demanding tasks are defined in function of the amount of information that needs to be maintained in working memory. To measure performances and user experience, efficacy (number of successful tasks) and efficiency (time need and number of actions) were observed, while cognitive absorption, emotions and satisfaction were collected by the use of a questionnaire. Finally, the results indicate that the use of a touch sensitive screen impacts efficacy but not on time efficiency. More precisely, efficacy significantly decreases when the user executes complex tasks in terms of interactions needed and cognitive demands, while more interestingly, efficacy significantly increases when the user executes tasks that are complex in terms of interaction needed and low in terms of cognitive demands. Furthermore, the outcomes indicate the lack of any observed effect on time efficiency can be explained by the tendency of user to abort tasks when a tablet is used.