The Aha! moment: Is insight a different form of problem solving?

In everyday life, we mainly solve problems with a conscious solution search (non-insight). However, sometimes a perplexing problem is resolved by a quantum leap in understanding. This phenomenon is known as the Aha! experience (insight). Although insight has a distinct phenomenological and behavioral signature, its driving mechanism remains debated. Weisberg (2015) proposed an integrated theory of insight arguing that insight, like non-insight, mainly depends on conscious, cognitive operations with restructuring as a distinguishing feature of insight. However, only if those operations lead to an impasse, insight is achieved through unconscious processes. We assessed some of the premises of this theory by asking participants (N = 42) to solve 70 word puzzles (CRAT) that can either be solved with insight or non-insight. For each puzzle, participants indicated word puzzle difficulty, solution confidence, solution suddenness, and the experiences of impasse and restructuring. As expected, participants reported higher suddenness of and confidence in insight solutions than non-insightful ones. Surprisingly, we could not corroborate the otherwise consistently reported higher solution accuracy and faster solution speed for insight. Crucially, as suggested by the integrated theory of insight, impasse was not a prerequisite for insight to occur. Although restructuring, indeed, preceded insight solutions more often, it seemed a more general problem-solving skill also applied for non-insight solutions. Moreover, early on, participants reported an increased experience of problem difficulty for puzzles later solved with insight. This ability to report on the solution search of insight demonstrates that, as proposed by the theory, insight involves conscious, cognitive operations.

Insight and non-insight problem solving: A heart rate variability study.

Occasionally, problems are solved with a sudden Aha! moment (insight), while the mundane approach to solving problems is analytical (non-insight). At first glance, non-insight appears to depend on the availability and taxation of cognitive resources to execute the step-by-step approach, whereas insight does not, or to a lesser extent. However, this remains debated. To investigate the reliance of both solution types on cognitive resources, we assessed the involvement of the prefrontal cortex using vagally mediated heart rate variability (vmHRV) as an index. Participants (N = 68) solved 70 compound remote associates word puzzles solvable with insight and non-insight. Before, during, and after solving the word puzzles, we measured the vmHRV. Our results showed that resting-state vmHRV (trait) showed a negative association with behavioural performance for both solution types. This might reflect inter-individual differences in inhibitory control. As the solution search requires one to think of remote associations, inhibitory control might hamper rather than aid this process. Furthermore, we observed, for both solution types, a vmHRV increase from resting-state to solution search (state), lingering on in the post-task recovery period. This could mark the increase of prefrontal resources to promote an open-minded stance, essential for divergent thinking, which arguably is crucial for this task. Our findings suggest that, at a general level, both solution types share common aspects. However, a closer analysis of early and late solutions and puzzle difficulty suggested that metacognitive differentiation between insight and non-insight improved with higher trait vmHRV, and that a unique association between trait vmHRV and puzzle difficulty was present for each solution type.

Aha! under pressure: The Aha! experience is not constrained by cognitive load.

The Aha! moment- the sudden insight sometimes reached when solving a vexing problem- entails a different problem-solving experience than solution retrieval reached by an analytical, multistep strategy (i.e., non-insight). To date, the (un)conscious nature of insight remains debated. We addressed this by studying insight under cognitive load. If insight and non-insight problem solving rely on conscious, effortful processes, they should both be influenced by a concurrent cognitive load. However, if unconscious processes characterize insight, cognitive load might not affect it at all. Using a dual-task paradigm, young, healthy adults (N = 106) solved 70 word puzzles under different cognitive loads. We confirmed that insight solutions were more often correct and received higher solution confidence. Importantly, as cognitive load increased, non-insight solutions became less frequent and required more solution time, whereas insightful ones remained mostly unaffected. This implies that insight problem solving did not compete for limited cognitive resources.

Validity of the Empatica E4 wristband to estimate resting-state heart rate variability in a lab-based context.

Lab research might benefit from the advantages of wearable devices, such as their ease of use, to estimate pulse rate (PR) and pulse rate variability (PRV) as an equivalent for heart rate (HR) and heart rate variability. However, before implementing them in a lab context, the validity of the PR and PRV, also on ultra-short time scales (e.g., 30s), needs to be confirmed. We recorded heart activity simultaneously with an E4 wristband and an ECG device in a seated resting condition for 5 min. Our results showed that HR, RMSSD, SDNN and LF, but not HF, were validly estimated by the E4 wristband. Furthermore, the E4 wristband could validly estimate PR with recording lengths as short as 10s. RMSSD and SDNN were validly estimated using 30s or 120 s or an average of multiple short intervals (10s), while HF likely requires longer recording intervals. Based on this study, we formulated several recommendations for using the E4 wristband in a lab context.