General fluid intelligence and complex thought as supported by the Multiple Demand (MD) network
Only published papers are included; for preprints, see Papers.
Last Updated: May 2024
The domain-generality of the Multiple Demand network
In addition to numerous specialized brain areas and networks, which support the processing of information in particular domains (e.g., face recognition, language, or social reasoning), the association cortex contains a bilateral network of frontal and parietal areas that are highly domain-general. These areas are engaged during diverse goal-directed behaviors and have been linked to general fluid intelligence, which encompasses executive functions (working memory, cognitive control, and attention), domain-general reasoning abilities, skill acquisition, and novel problem solving. Some domains, like numerical cognition, logical reasoning, and the processing of computer code also recruit this network.
This paper provides evidence from robust individual-subject analyses for the domain-generality of the Multiple Demand brain areas based on overlap among diverse demanding cognitive tasks.
Individual differences in the activity of the Multiple Demand network
This paper shows that activity in the Multiple Demand network is associated with individual differences in working memory and fluid intelligence.
In this paper, we asked whether activity in the Multiple Demand network differs between monolingual and bilingual individuals, per a famous claim that being bilingual improves one’s general cognitive control abilities. To our surprise, we found that MD areas are more strongly engaged during demanding tasks and are more strongly modulated by task difficulty in bilinguals, which is generally associated with better task performance and higher scores on an IQ task (e.g., Assem et al., 2020, Cortex). In this study, we don’t see strong differences in task performance between bilinguals and monolinguals, and, as we acknowledge, the two populations differ in more ways than their linguistic profile. Nevertheless, this finding may be worth following up on.
Causal role of the Multiple Demand network in fluid intelligence
This paper shows that damage to the Multiple Demand network is associated with deficits in fluid intelligence.
