MULTI-MODAL USER INTERFACES: EFFECTS OF REDUNDANT AND COMPLEMENTARY APPROACHES IN HIGH STIMULI ENVIRONMENTS
Author: Steven J. Kerr, Carmen Siau
Abstract: Professionals such as public safety workers have to use communication devices as part of their job which can be high stress and involve demands on their cognitive resources that would be better applied to their task at hand. Multi Modal User Interfaces (MMUI), have been proposed as a way of supporting more flexible, efficient interfaces, appropriately conveying information to users whilst they are busily involved in their tasks. In this paper we describe a usability study dealing with two types of MMUI environments, redundant and complementary, under a controlled driving simulation environment and explore how these two approaches plus increasing modality impacts user interactions with their primary task of driving plus their secondary task of communicating.
Results show that increasing modalities potentially help users communicate more effectively in high stimuli environments though modality conflict has to be considered when the user cannot ignore it e.g. audio instructions on driving whilst talking to someone. Whilst complementary modalities show a slightly higher cognitive load rating, in general there appears little difference between redundant and complementary approaches.
Keywords: multimodal interfaces, communication devices, cognitive load, usability