Poster F41, Tuesday, March 28, 8:00 – 10:00 am, Pacific Concourse
Decoding Free Choices: Influences of Unconscious Priming on Voluntary Actions
Martyn Teuchies1, Jelle Demanet1, Nura Sidarus2, Patrick Haggard2, Michaël Stevens1, David Wisniewski1, Marcel Brass1; 1Ghent University, 2University College London
The ability to make voluntary, free choices is fundamental to what it means to be human. A key brain region that is involved in free choices is the rostral cingulate zone (RCZ), which is part of the medial frontal cortex. Previous research has shown that activity in this brain region can be modulated by bottom-up information while making free choices. The current study extends those findings, and shows, for the first time, that activation in the RCZ can also be modulated by subliminal information. We used a subliminal response priming paradigm to bias free and cued choices. Using univariate fMRI analyses we observed more activation in the RCZ when participants made a choice that went against the prime's suggestion, compared to when they chose according to the prime. This shows that the RCZ plays an important role in overcoming externally-triggered conflict between different response options, even when the stimuli triggering this conflict are not consciously perceived. We also carried out a multi voxel pattern analysis (MVPA) to investigate which brain areas contained predictive information about the choice a participant would make. We used a whole brain searchlight analysis to decode whether participants were going to make a left or right response. Based on previous studies we then looked at the predictive information in predefined ROIs in the precuneus and the anterior medial frontal cortex. We could predict free choices above chance level from the pattern of brain activity in the precuneus but not in the anterior medial frontal cortex.
Topic Area: EXECUTIVE PROCESSES: Other