2020 Worldwide Postdoc/Student Competition Winners
- Psychology Department, University of Milano-Bicocca, Milan, Italy
- PhD Program in Neuroscience, School of Medicine and Surgery, University of Milano-Bicocca, Milano, Italy
It is difficult to make more than one voluntary action at a time. This limitation also applies before we move: it is difficult to prepare multiple actions in parallel. The current project aims at exploring this fundamental bandwidth limitation on voluntary actions. In particular, I aim to examine whether and how the number of stimulus-response alternatives (the degree of uncertainty about the upcoming movement) modulates the neural activity during motor preparation of voluntary actions (i.e. the power of beta-band oscillatory activity and the readiness potential (RP)), as well as the behavioral experience of agency that accompanies intentional actions (measured through the intentional binding effect). According to the multidimensional nature of volition, I will assess two different dimensions of uncertainty: the number of possible action alternatives (“what”) and the timing at which the action should be executed (“when”). To this aim, I will use a reinforcement learning task which embeds endogenous actions within the broader framework of decision-making, by contrasting no-choice conditions and choice conditions with a different number of stimulus-response alternatives. I suggest that EEG variability could be a proxy for uncertainty: as the brain reduces the number of possible actions during preparation, the variability of EEG should also reduce, reflecting convergence on the single brain pattern associated with the action that will eventually be made. Moreover, I expect that increasing the degree of uncertainty about the possible course of action corresponds to increasing levels of agency. Finally, I aim to embed my results into the philosophical debate about responsibility: could an endogenous process of uncertainty reduction play a role in the agent’s feeling of responsibly for his/her action?
This project investigates the neurocognitive functional role of attention and conscious awareness in action. Past neuroscientific studies have provided some evidence that people can attend and subsequently respond to external stimuli without conscious awareness, while others claim that this is true only for spontaneous actions and not deliberate actions. Accordingly, this project investigates how people attend and respond to visual stimuli that have been perceptually masked. Through behavioral, self-report, and high-temporal-resolution EEG measures of electrical brain activity, this project characterizes the neural processes that underly spatial attention orientation, conscious awareness, and the preparation, execution, and accuracy of motor responses. It also assesses how attention and conscious awareness affects judgements of responsibility for actions.
Marie-Christine Nizzi, Ph.D., Harvard University
Nadya Vasilyeva, Ph.D., Princeton University