Implicit Learning of True and False Belief Sequences

Abstract

To investigate whether people can implicitly learn regularities in a social context, we developed a new implicit sequence learning task combining elements from classic false belief and serial reaction time tasks. Participants learned that protagonists were offered flowers at four locations. The protagonists' beliefs concerning the flowers were true or false, depending on their orientation, respectively, toward the scene (so that the flowers could be seen) or away from it. Unbeknown to the participants, there was a fixed belief-related sequence involving three dimensions (identity of the two protagonists, true-false belief orientation held by the protagonists, and flower location as believed by the protagonists). Participants had to indicate as fast as possible where the flowers were located (Experiment 1), or how many flowers were given (Experiment 2) according to the protagonists. Experiment 1 combined perceptual and motor processes (as both the belief-related sequence and motor responses referred to location), whereas Experiment 2 unconfounded the sequence and motor responses, allowing to investigate pure perceptual implicit learning. For reasons of comparison, two non-social conditions were created in Experiment 2 by replacing the protagonists with two non-social objects—colored cameras or shapes. Results revealed significant implicit sequence learning of all belief-related dimensions in Experiment 1, and of true-false belief orientation in Experiment 2, even without a motor confound. Importantly, there were faster reaction times and stronger sequence learning effects in the social than in the non-social conditions. The present findings demonstrate for the first time that people are able to implicitly learn belief-related sequences.

The posterior cerebellum supports implicit learning of social belief sequences

“…We used a novel implicit belief learning task, which combines elements of a classic serial reaction time (SRT) task for implicit learning (Nissen & Bullemer, 1987) with social elements from a false belief task (Wimmer & Perner, 1983). Accordingly, we named it a Belief SRT task (Ma et al, 2021).…”

“…In the Belief SRT task (Fig. 1A; Ma et al, 2021), four little Smurfs appeared on the top of the screen, which marked the location of the target flowers. The two protagonists, Papa Smurf and Smurfette, were each shown individually at the bottom of the screen with their face directed to or away from the screen.…”

“…Moreover, note that participants required an extensive 30-minute practice on the control task, but not the false-belief task, before entering the scanner. Perhaps another control task could be developed based on elements of the false-photograph task, which requires participants to infer whether a photo taken by a camera is consistent with current reality or outdated (Apperly, Samson, Chiavarino, Bickerton, & Humphreys, 2007;Ma et al, 2021;Saxe, 2006). For example, a camera that is orientated toward flowers (representing a "true" or current photo) or away from flowers (representing an "false" or outdated photo).…”

The Role of the Posterior Cerebellum in Dysfunctional Social Sequencing

“…2A), goal-directed intentions [67], and traits of others [34],Fig. 2B) not only at an explicit level, but also at an implicit level [68],Fig. 2C).…”

“…C Implicit Belief Serial Response Time: participants had to answer as fast as possible how many flowers the protagonist could see when oriented to the flowers; and when not, how many flowers he or she had seen previously. Unbeknownst to them, there was a fixed order of true and false beliefs held by the protagonists [68] both learning mechanisms interact with each other in the cerebellum or brain in general? • involved in closed-loops with canonical cortical areas in social processing (i.e., TPJ and mPFC) during these tasks, which seem to differ from well-known closedloops in motor behaviors?…”