title: Neuroimaging of the joint Simon effect with believed biological and non-biological co-actors.
abstract: Performing a task alone or together with another agent can produce different outcomes. The current study used event-related functional magnetic resonance imaging (fMRI) to investigate the neural underpinnings when participants performed a Go/Nogo task alone or complementarily with another co-actor (unseen), whom was believed to be another human or a computer. During both complementary tasks, reaction time data suggested that participants integrated the potential action of their co-actor in their own action planning. Compared to the single-actor task, increased parietal and precentral activity during complementary tasks as shown in the fMRI data further suggested representation of the co-actor's response. The superior frontal gyrus of the medial prefrontal cortex was differentially activated in the human co-actor condition compared to the computer co-actor condition. The medial prefrontal cortex, involved thinking about the beliefs and intentions of other people, possibly reflects a social-cognitive aspect or self-other discrimination during the joint task when believing a biological co-actor is present. Our results suggest that action co-representation can occur even oﬄine with any agent type given a priori information that they are co-acting; however, additional regions are recruited when participants believe they are task-sharing with another human.
authors.affiliation: Cognitive Electrophysiology Lab: Control, Aging, Sleep, and Emotion, Department of Psychology, National Cheng Kung University Tainan, Taiwan ; Department of Life Sciences, National Cheng Kung University Tainan, Taiwan.
authors.forename: Tanya
authors.initials: T
authors.lastname: Wen
authors.affiliation: Cognitive Electrophysiology Lab: Control, Aging, Sleep, and Emotion, Department of Psychology, National Cheng Kung University Tainan, Taiwan ; Institute of Allied Health Sciences, National Cheng Kung University Tainan, Taiwan ; Department of Public Health, National Cheng Kung University Tainan, Taiwan.
authors.forename: Shulan
authors.initials: S
authors.lastname: Hsieh
keywords: Go/Nogo; action representation; biological co-actor; joint Simon task; medial prefrontal cortex