We conducted four experiments, that involved brain stimulation, EEG, fRMI and novel behavioral experimental designs. This variety of experiments approached metacognitive decision-making from different angles, allowing us to construct a model of metacognitive decision-making at the end of the project. Below I will highlight the main results achieved so far, as well as the ongoing work and expected progress.
- In daily life, our decisions are frequently guided by regularities in our environment. However, such contingencies are not always explicitly present and sometimes need to be inferred. In our experiment, we showed how predictive (contextual) information in the environment influenced decision-making despite a lack of awareness of the meaning (or presence) of this information. These implicit inferences emerge through changes in internally and externally oriented neural networks. Our results demonstrate that the prefrontal cortex plays an important role in the transformation of externally driven stimulus–outcome events into predictive internalized models of the world (see https://www.jneurosci.org/content/jneuro/39/26/5183.full.pdf )
- To follow up on the above-described results, we aimed to causally test the involvement of prefrontal cortex in internally oriented processes (metacognition, predictions). What happens when neural activity in prefrontal cortex becomes 'abnormal' or altered? Interestingly, we observed that participants were no longer able to use predictive contextual information to adjust decision-making when activity in prefrontal cortex was altered. (manuscript in preparation)
- Our next experiments addressed what kind information is being used to compute an estimate about the quality of our decisions. Considered together, our results demonstrate that post-decisional information contributes to metacognition, thereby evaluating not only what one perceives (e.g. strength of perceptual evidence) but also how one responds towards perceptual events. In this way, metacognition can be seen as an internalization of external feedback processing and error monitoring
https://www.nature.com/articles/s41598-020-60382-y(öffnet in neuem Fenster) and
https://www.jneurosci.org/content/jneuro/37/4/781.full.pdf(öffnet in neuem Fenster)- To examine the mechanisms of metacognitive decision-making further, and investigate how sensory and 'higher-order' areas (such as prefrontal cortex) interact we used fMRI and brain stimulation (participants performed a total of 6 sessions in six different weeks). Results of this experiment are expected to provide great insight into the workings of metacognitive decision-making, and will be important in arbitrating a currently fiercely held debate within the literature. This rich dataset will be useful for many (European) researchers interested in decision-making (including medical doctors, psychologists, and neuroscientists). (manuscripts in preparation)
- To uncover how daily fluctuations in cognitive performance induced by drowsiness affect decision-making we are currently examining the depth of the effects of drowsiness. For this, we are investigating how drowsiness alters decision-making on a 'low-level' (can you tell the difference between an arrow pointing leftwards or rightwards?) and 'high-level' (are you able to stop an ongoing action, are you able to ignore irrelevant information, or are you able to estimate how well you are performing), and whether an over-arching effect of drowsiness can be observed in a series of 8 experiments. (in preparation)