Differential recruitment of theory of mind brain network across three tasks: An independent component analysis.

Social neuroscience research has focused on an identified network of brain regions primarily associated with processing Theory of Mind (ToM). However, ToM is a broad cognitive process, which encompasses several sub-processes, such as mental state detection and intentional attribution, and the connectivity of brain regions underlying the broader ToM network in response to paradigms assessing these sub-processes requires further characterization. Standard fMRI analyses which focus only on brain activity cannot capture information about ToM processing at a network level. An alternative method, independent component analysis (ICA), is a data-driven technique used to isolate intrinsic connectivity networks, and this approach provides insight into network-level regional recruitment. In this fMRI study, three complementary, but distinct ToM tasks assessing mental state detection (e.g. RMIE: Reading the Mind in the Eyes; RMIV: Reading the Mind in the Voice) and intentional attribution (Causality task) were each analyzed using ICA in order to separately characterize the recruitment and functional connectivity of core nodes in the ToM network in response to the sub-processes of ToM. Based on visual comparison of the derived networks for each task, the spatiotemporal network patterns were similar between the RMIE and RMIV tasks, which elicited mentalizing about the mental states of others, and these networks differed from the network derived for the Causality task, which elicited mentalizing about goal-directed actions. The medial prefrontal cortex, precuneus, and right inferior frontal gyrus were seen in the components with the highest correlation with the task condition for each of the tasks highlighting the role of these regions in general ToM processing. Using a data-driven approach, the current study captured the differences in task-related brain response to ToM in three distinct ToM paradigms. The findings of this study further elucidate the neural mechanisms associated with mental state detection and causal attribution, which represent possible sub-processes of the complex construct of ToM processing.

Brain Mechanisms Underlying Reading the Mind from Eyes, Voice, and Actions.

Evidence from cognitive and social neuroscience research suggests that Theory of Mind (ToM), the ability to attribute mental states to others, is mediated by a group of brain regions collectively known as the ToM network. Nevertheless, there is significant variability in the functional activation of regions within this network across tasks. The goal of the present functional magnetic resonance imaging (fMRI) study was to examine the common and differential neural mechanisms of two aspects of ToM processing (emotion/mental-state recognition and intentional attribution) using three distinct, but complementary ToM tasks (Reading the Mind in the Eyes (RMIE), Reading the Mind in the Voice (RMIV), and Intentional Causal Attribution) in healthy adults. Participant accuracy was significantly worse in the ToM compared to the control condition across all tasks. Brain activation analyses replicated previously reported activation in inferior frontal gyrus (IFG) and middle temporal gyrus extending to posterior superior temporal sulcus (pSTS) in RMIE. Activation in the fusiform gyrus and bilateral middle temporal gyrus extending to temporo-parietal junction (TPJ) was unique to causality task. A region-of-interest analysis revealed shared activation in left IFG for RMIE and RMIV as well as TPJ recruitment specific to the causality task. The role of right TPJ in the causality task was further supported by a percent signal change analysis. A conjunction analysis revealed overlap in left IFG, left precentral gyrus, and left superior frontal gyrus activity across all tasks. These findings highlight common and differential recruitment of ToM regions according to task demand.

The impact of atypical sensory processing on social impairments in autism spectrum disorder.

Altered sensory processing has been an important feature of the clinical descriptions of autism spectrum disorder (ASD). There is evidence that sensory dysregulation arises early in the progression of ASD and impacts social functioning. This paper reviews behavioral and neurobiological evidence that describes how sensory deficits across multiple modalities (vision, hearing, touch, olfaction, gustation, and multisensory integration) could impact social functions in ASD. Theoretical models of ASD and their implications for the relationship between sensory and social functioning are discussed. Furthermore, neural differences in anatomy, function, and connectivity of different regions underlying sensory and social processing are also discussed. We conclude that there are multiple mechanisms through which early sensory dysregulation in ASD could cascade into social deficits across development. Future research is needed to clarify these mechanisms, and specific focus should be given to distinguish between deficits in primary sensory processing and altered top-down attentional and cognitive processes.