Abstract. There are diverging operationalizations of insight in experimental research, such as endogenous, that is, problems solved correctly via insight by the participant or comprehended suddenly after the solution was revealed following an unsuccessful solution attempt. The question arises how comparable these types of insight are. Here, we set out (1) to evaluate the usefulness of the matchstick arithmetic task for investigating cognitive and neural processes underlying insight-based problem solving, (2) whether the Aha! experience is diminished over a multitude of trials, and (3) to compare true (correctly solved), false (incorrectly solved), and induced insights. To this end, we analyzed solution rates, response times, the strength of subjective Aha! experience, and event-related potentials. Our results showed that approximately 40 trials did not weaken the Aha! experience, but that it was important how much time participants are provided for a solution attempt. Moreover, in line with previous research, endogenous insights differ electrophysiologically from induced insights, but especially so for whether an endogenous insight was true or false. The differentiation between true, false, and induced insights was further supported by differing Aha! ratings. Taken together, our study provides important information on aspects that need to be taken into consideration for the neuroscientific investigation of insight problem-solving and show that matchstick equations appear well-suited for this endeavor. Moreover, our results underline the importance of the respective operationalization of insight. File information. (1) SPSS raw data table of the behavioral data from all subjects included in the data analysis. Item 39 (invalid template solution) was also excluded. (2) SPSS table with ERP data for all bins and the three conditions true, false, and induced insight. Mean amplitude in microvolts was exported for 250 ms bins between -2000 and -250 ms before the response. All raw data files (logfiles from Presentation or raw EEG data files from BrainVision Recorder) can be requested from jasmin.kizilirmak@dzne.de