Electrophysiological examination of response-related interference while dual-tasking: is it motoric or attentional?

Usability enhancement based on usability heuristics: An examination of the underlying mechanism utilizing the psychological-refractory-period paradigm

User Interface (UI) design practices often abide by popular usability heuristics such as Nielsen's (1994) "10 usability heuristics for user interface design" or Gerhardt-Powals' (1996) cognitive engineering principles. To examine the underlying mechanism of user performance enhancement by following some of these usability heuristics, we compared user performance between two device conditions: one representing design practices following two selected sets of usability heuristics (experimental condition) and the other without following them (control condition). As a research framework, we adopted the psychological-refractory-period (PRP) paradigm along with the locus-of-slack logic, a well-established dual-task paradigm for examining the nature of cognitive benefits caused by experimental manipulations. Results showed that the experimental-device condition that followed the usability heuristics yielded faster performance than the control condition, especially when the stimulus-onset-asynchrony between the two tasks was long than when it was short. According to the locus-of-slack logic, these results suggest that the nature of cognitive benefits caused by following the usability heuristics is more likely to be due to shortening of the response-activation stage (rather than the response-selection stage). These findings suggest that following the two usability heuristics tends to facilitate a specific stage of the information processes more than other stages.