The Role of the Ventrolateral Anterior Temporal Lobes in Social Cognition

A key challenge for neurobiological models of social cognition is to elucidate whether brain regions are specialised for that domain. In recent years, discussion surrounding the role of anterior temporal regions epitomises such debates; some argue the anterior temporal lobe (ATL) is part of a domain‐specific network for social processing, while others claim it comprises a domain‐general hub for semantic representation. In the present study, we used ATL‐optimised fMRI to map the contribution of different ATL structures to a variety of paradigms frequently used to probe a crucial social ability, namely ‘theory of mind’ (ToM). Using multiple tasks enables a clearer attribution of activation to ToM as opposed to idiosyncratic features of stimuli. Further, we directly explored whether these same structures are also activated by a non‐social task probing semantic representations. We revealed that common to all of the tasks was activation of a key ventrolateral ATL region that is often invisible to standard fMRI. This constitutes novel evidence in support of the view that the ventrolateral ATL contributes to social cognition via a domain‐general role in semantic processing and against claims of a specialised social function

Overlapping Neural Correlates Underpin Theory of Mind and Semantic Cognition:Evidence from a Meta-Analysis of 344 Functional Neuroimaging Studies

Key unanswered questions for cognitive neuroscience include whether social cognition is underpinned by specialised brain regions, and to what extent it simultaneously depends on more domain-general systems. Until we glean a better understanding of the contribution made by domain-general cognitive systems, theories of social cognition will remain fundamentally limited. In the present study, we evaluate a recent and novel proposal that the semantic cognition network plays a crucial role in supporting social processes. We specifically focus on theory of mind (ToM) abilities and adopt a meta-analytic activation likelihood estimation approach to synthesise the results of a large set of functional neuroimaging studies. Our primary aim was to establish the degree of topological overlap between the cortical networks involved in ToM and semantic tasks. Moreover, we sought to account for key methodological differences across the two sets of tasks, including the fact that ToM studies tend to use nonverbal stimuli while the semantics literature is dominated by language-based tasks. We observed extensive overlap between the two networks in regions strongly implicated in semantic cognition, including the anterior temporal lobes and the left temporoparietal junction (TPJ). Activation specific to ToM was identified in the right TPJ, bilateral anterior mPFC, and right precuneus. These findings persisted even after controlling for discrepancies in the types of experimental stimuli used in each domain. Overall, the findings support the claim that ToM draws upon more general semantic retrieval processes and are against the view that ToM is underpinned solely by a domain-specific social neurocognitive system

Graded functional organisation in the left inferior frontal gyrus: evidence from task-free and task-based functional connectivity

The left inferior frontal gyrus (LIFG) has been ascribed key roles in numerous cognitive domains, such as language and executive function. However, its functional organisation is unclear. Possibilities include a singular domain-general function, or multiple functions that can be mapped onto distinct subregions. Furthermore, spatial transition in function may be either abrupt or graded. The present study explored the topographical organisation of the LIFG using a bimodal data-driven approach. We extracted functional connectivity (FC) gradients from 1) resting-state fMRI time-series, and 2) co-activation patterns derived meta-analytically from heterogenous sets of task data. We then sought to characterize the FC differences underpinning these gradients with seed-based resting-state FC, meta-analytic co-activation modelling and functional decoding analyses. Both analytic approaches converged on graded FC changes along two main organisational axes. An anterior-posterior gradient shifted from being preferentially associated with high-level control networks (anterior LIFG) to being more tightly coupled with perceptually-driven networks (posterior). A second dorsal-ventral axis was characterized by higher connectivity with domain-general control networks on one hand (dorsal LIFG), and with the semantic network, on the other (ventral). These results provide novel insights into an overarching graded functional organisation of the LIFG that explains its role in multiple cognitive domains