Between Control and Disruption: Effects of Instant Messaging Notifications on Cognitive and Perceptual Process

This study investigates the effects of instant messaging notifications under varying levels of interface controllability and message pragmatic functions on attention, cognitive load, time perception and performance in task contexts. The results show that interface design affects cognitive load and time perception. Interfaces granting users control and non-mandatory interactions reduce load and induce time underestimation. Low-control interfaces that obstruct the reading area increase load and lead to time overestimation. Directive content reduces task performance in certain interface conditions. Correlational analyses revealed that attention is positively associated with task performance, cognitive load is negatively associated with performance, and physical demand and frustration are associated with time overestimation. Cluster analysis identified three user response patterns, indicating that different user characteristics influence the effects of notification interfaces. These findings emphasize the importance of preserving user control in notification design. Transient, auto-dismissing, non-mandatory interfaces are recommended to mitigate the negative impact of interruptions.