D. Welke, E. A. Vessel
A series of internal states, proceeding from curiosity (drive state) to insight (uncertainty reduction) to pleasure (reward and reinforcement), might represent a fundamental pathway for motivated learning. Here we present a paradigm that combines measurement of curiosity, insight (aha), understanding and liking to outline the contours of this epistemic arc and trace their neuronal correlates. In two preregistered experiments we employ the "title effect" - the fact that additional semantic information can change how one understands and enjoys a piece of art. Participants viewed paintings and rated their curiosity for seeing the title. This was followed either by the original title or a dummy title lacking additional information, and a second presentation of the image, after which participants rated their strength of aha, aesthetic liking, and feeling of understanding the artwork. In a behavioral study (N=55 participants) we establish empirically that visual art with their titles can prompt strong feelings of aha. The association between ratings is complex and shaped by the type and amount of information in the stimuli; e.g. aha is linearly linked to liking and nonlinearly to understanding. In an EEG, ECG and eye tracking study with the same paradigm (N=49 participants) we use time-resolved decoding to trace the temporal sequence of processing. Understanding can be decoded from various (neuro)physiological correlates, over extended timespans. Robust decoding of curiosity both before and after the titles substantiates its relevance within the epistemic arc. Aha could be decoded from pupil size, but not from the EEG. Lastly, a fast initial EEG response was linked to aesthetic liking. Though much remains to explore, our study provides a new window into core behavioral and physiological properties of motivated information foraging.