A Domain-General Cognitive Core Defined in Multimodally Parcellated Human Cortex

Abstract

Numerous brain imaging studies identified a domain-general or “multiple-demand” (MD) activation pattern accompanying many tasks and may play a core role in cognitive control. Though this finding is well established, the limited spatial localization provided by traditional imaging methods precluded a consensus regarding the precise anatomy, functional differentiation, and connectivity of the MD system. To address these limitations, we used data from 449 subjects from the Human Connectome Project, with the cortex of each individual parcellated using neurobiologically grounded multimodal MRI features. The conjunction of three cognitive contrasts reveals a core of 10 widely distributed MD parcels per hemisphere that are most strongly activated and functionally interconnected, surrounded by a penumbra of 17 additional areas. Outside cerebral cortex, MD activation is most prominent in the caudate and cerebellum. Comparison with canonical resting-state networks shows MD regions concentrated in the fronto-parietal network but also engaging three other networks. MD activations show modest relative task preferences accompanying strong co-recruitment. With distributed anatomical organization, mosaic functional preferences, and strong interconnectivity, we suggest MD regions are well positioned to integrate and assemble the diverse components of cognitive operations. Our precise delineation of MD regions provides a basis for refined analyses of their functions.

The Dual Mechanisms of Cognitive Control (DMCC) Project

“…Second, the set of fronto-parietal regions that we identified here are consistent with prior work, which described a similar canonical cognitive control network (Cole & Schneider, 2007;Dosenbach et al, 2008;Vincent et al, 2008). This network has also been referred to as the multiple-demand network (Camilleri et al, 2018;Duncan, 2010;Duncan & Owen, 2000), in that it exhibits consistent responsivity to increasing control demands across a range of task contexts (Assem et al, 2020;Fedorenko et al, 2013;Shashidhara et al, 2019). This set is primarily bilateral and includes not only mid-lateral prefrontal cortex and parietal cortex, but also other regions linked to cognitive control, such as the anterior insula / frontal operculum, and medial frontal cortex / dorsal anterior cingulate.…”

Comprehension of computer code relies primarily on domain-general executive brain regions

“…The fact that the MD system responds to code problems over and above content-matched sentence problems underscores the role of domain-general executive processes in code comprehension. Although cognitive processes underlying code interpretation bear parallels to logic and math tasks ( Papert, 1972 ; Pennington and Grabowski, 1990 ; Perkins and Simmons, 1988 ) and to natural language comprehension/generation ( Fedorenko et al, 2019 ; Hermans and Aldewereld, 2017 ), the neural activity we observe primarily resembles activity observed in response to domain-general executive tasks ( Assem et al, 2020 ; Duncan, 2010 ; Fedorenko et al, 2013 ). In particular, code comprehension elicits bilateral responses within the MD system, in contrast to math and logic tasks that tend to elicit left-lateralized responses within the MD system, and in contrast to language tasks that elicit responses in the spatially and functionally distinct language system.…”

“…We found that responses in the MD system were driven both by the processing of problem content (e.g., summing the contents of an array) and by code comprehension (e.g., identifying variables referring to an array and its elements, interpreting a for loop, realizing that the output of the program is the variable being updated inside the for loop). Both of these processes plausibly require attention, working memory, inhibitory control, planning, and general flexible relational reasoning – cognitive processes long linked to the MD system ( Duncan, 2010 ; Duncan, 2013 ; Duncan and Owen, 2000 ; Miller and Cohen, 2001 ) in both humans ( Assem et al, 2020 ; Shashidhara et al, 2019a ; Woolgar et al, 2018 ) and non-human primates ( Freedman et al, 2001 ; Miller et al, 1996 ; Mitchell et al, 2016 ). A recent study ( Huang et al, 2019 ) reported neural overlap between operations on programming data structures (which require both code comprehension and the processing of problem content) and a mental rotation task (which requires spatial reasoning).…”

“…In both conditions, they performed a two-alternative forced-choice task at the end of each trial to indicate the set of locations they just saw. The hard >easy contrast has been previously shown to reliably activate bilateral frontal and parietal MD regions ( Assem et al, 2020 ; Blank et al, 2014 ; Fedorenko et al, 2013 ). Numerous studies have shown that the same brain regions are activated by diverse executively demanding tasks ( Duncan and Owen, 2000 ; Fedorenko et al, 2013 ; Hugdahl et al, 2015 ; Shashidhara et al, 2019a ; Woolgar et al, 2011 ).…”

“…Many cognitive processes are known to evoke activity in specific brain regions/networks: thus, observing activity for the task of interest in a particular region or network with a known function can indicate which cognitive processes are likely engaged in that task ( Mather et al, 2013 ). Prior research ( Assem et al, 2020 ; Duncan, 2010 ; Duncan, 2013 ; Duncan and Owen, 2000 ) has shown that executive processes – such as attention, working memory, and cognitive control – recruit a set of bilateral frontal and parietal brain regions collectively known as the multiple demand (MD) system. If code comprehension primarily relies on domain-general executive processes, we expect to observe code-evoked responses within the MD system, distributed across both hemispheres.…”