Tonja Machulla

Exploring notifications in smart home environments

Notifications are a core mechanism of current smart devices. They inform about a variety of events including messages, social network comments, and application updates. While users appreciate the awareness that notifications provide, notifications cause distraction, higher cognitive load, and task interruptions. With the increasing importance of smart environments, the number of sensors that could trigger notifications will increase dramatically. A flower with a moisture sensor, for example, could create a notification whenever the flower needs water. We assume that current notification mechanisms will not scale with the increasing number of notifications. We therefore explore notification mechanisms for smart homes. Notifications are shown on smartphones, on displays in the environment, next to the sending objects, or on the users body. In an online survey, we compare the four locations in four scenarios. While different aspects influence the perceived suitability of each notification location, the smartphone generally is rated the best.

Impact of reviewing lifelogging photos on recalling episodic memories

Photos are a rich and popular form for preserving memories. Thus, they are widely used as cues to augment human memory. Near-continuous capture and sharing of photos have generated a need to summarize and review relevant photos to revive important events. However, there is limited work on exploring how regular reviewing of selected photos influence overall recall of past events. In this paper, we present an experiment to investigate the effect of regular reviewing of egocentric lifelogging photos on the formation and retrieval of autobiographic memories. Our approach protects the privacy of the participants and provides improved validation for their memory performance compared to existing approaches. The results of our experiment are a step towards developing memory shaping algorithms that accentuate or attenuate memories on demand.

Decision-Making under Uncertainty: How the Amount of Presented Uncertainty Influences User Behavior

In everyday life, people regularly make decisions based on uncertain data, e.g., when using a navigation device or looking at the weather forecast. In our work, we compare four representations that communicate different amounts of uncertainty information to the user. We compared them in a study by publishing a web-based game on Facebook. In total, 44 users played 991 turns. We analyzed the turns by logging game metrics such as the gain per turn and included a survey element. The results show that abundance of uncertainty information leads to taking unnecessary risks. However, representations with aggregated detailed uncertainty provide a good trade-off between being understandable by the players and encouraging medium risks with high gains. Absence of uncertainty information reduces the risk taking and leads to more won turns, but with the lowest money gain.

Building Cognition-Aware Systems: A Mobile Toolkit for Extracting Time-of-Day Fluctuations of Cognitive Performance

People’s alertness fluctuates across the day: at some times we are highly focused while at others we feel unable to concentrate. So far, extracting fluctuation patterns has been time and cost-intensive. Using an in-the-wild approach with 12 participants, we evaluated three cognitive tasks regarding their adequacy as a mobile and economical assessment tool of diurnal changes in mental performance. Participants completed the five-minute test battery on their smartphones multiple times a day for a period of 1-2 weeks. Our results show that people’s circadian rhythm can be obtained under unregulated non-laboratory conditions. Along with this validation study, we release our test battery as an open source library for future work towards cognition-aware systems as well as a tool for psychological and medical research. We discuss ways of integrating the toolkit and possibilities for implicitly measuring performance variations in common applications. The ability to detect systematic patterns in alertness levels will allow cognition-aware systems to provide in-situ assistance in accordance with users’ current cognitive capabilities and limitations.

Does audiovisual temporal recalibration store without stimulation

Recent studies have investigated adaptation to temporal discrepancies between different sensory modalities by first exposing participants to asynchronous multisensory signals, and subsequently assessing the magnitude of the adaptation effect (the size of the shift in subjective simultaneity). Although never reported, there is reason to assume that the strength of the adaptation effect declines during this measurement period. Usually, short re-exposures are interleaved with testing to prevent such declining. In the present study, we show that a decrease in the strength of adaptation still can take place, even when a common re-exposure procedure is used. In a second experiment, we investigated whether the observed decline is due to: (1) a dissipation of adaptation with the passage of time or, (2) a new adaptation induced by the test stimuli. We find that temporal adaptation does not dissipate with time but is stored until new sensory information, i.e., stimuli that differ from those used during the adaptation procedure, is presented. An alternative explanation, namely that adaptation decays over time but is re-established before the first test trial due to the experimental procedure we chose, is addressed in a control experiment. This finding is discussed in terms of Helsons adaptation level (AL) theory [1947, Adaptation-level as frame of reference for prediction of psychophysical data. The American Journal of Psychology, 60, 1–29], according to which the null point of any perceptual dimension, in our case the perception of simultaneity on the dimension of temporal order, is a summarizing statistic of all stimuli presented in the past. Any single stimulus pulls the AL toward its own value, and any single stimulus is judged as though it was being compared with the current AL.

Skim-reading Strategies in Sighted and Visually-Impaired Individuals: A Comparative Study

As the amount of readily available reading material increases, the ability to read selectively, or to skim-read, is becoming an important skill. In this paper, we report a comparative study of existing skim-reading strategies in sighted and visually impaired individuals. Using a think-aloud approach, we identified key features of visual documents that allow sighted users to adopt a highly flexible and goal-oriented approach to skim-reading. These features are mostly lost when documents are accessed in auditory form, as is commonly the case for visually impaired individuals. As a result, this group has to fall back on either less efficient or cognitively more demanding exploration strategies. From our results, we propose a list of six design implications to guide the development of future technologies assisting non-visual skimming.

Developing a Highly Automated Driving Scenario to Investigate User Intervention: When Things Go Wrong

Current levels of vehicle automation (i.e., SAE-L2) require users to be vigilant and to intervene when automated vehicles fail to perform appropriately. In this work, we developed a scenario for investigating how humans respond, in the absence of notifications for system failure. In order to develop better notifications to elicit user intervention, it is necessary to first understand how humans would intervene, even without the aid of in-vehicle notifications. We provide a description of how this is implemented in a driving simulator using Unity, a game engine. In addition, we report preliminary results. Overall, we found that participants were more aroused and cautious under conditions of low environment visibility, even though visibility had no bearing on the likelihood of vehicle automation to fail. We present recommendations for how the current scenario could be improved for subsequent research.