Biology subjects

Mwilambwe-Tshilobo, L.

Publications and source records attributed to Mwilambwe-Tshilobo, L..

4 recordsLinked to original sources

bioRxiv2025

Linguistic coupling between neural systems for speech production and comprehension during real-time dyadic conversations

The core use of human language is communicating complex ideas from one mind to another in everyday conversations. In conversations, comprehension and production processes are intertwined, as speakers soon become listeners, and listeners become speakers. Nonetheless, the neural systems underlying these faculties are typically studied in isolation, using paradigms that cannot fully engage our capacity for interactive communication, and with indirect measures of similarity. Here, we used an fMRI hyperscanning paradigm to measure neural activity simultaneously in pairs of subjects engaged in real-time, interactive conversations. We used contextual word embeddings from a large language model to quantify the linguistic coupling between production and comprehension systems within and across individual brains. We found a highly overlapping network of regions involved in both production and comprehension spanning much of the cortical language network. Our findings reveal that shared representations for both processes extend beyond the language network into areas associated with social cognition. Together, these results suggest that the specialized neural systems for speech perception and production align on a common set of linguistic features encoded in a broad cortical network for language and communication.

neuroscience↗

bioRxiv2024

Finding Agreement: fMRI-hyperscanning reveals that dyads explore in mental state space to align opinions.

Many prize synchrony as the ingredient that turns a discordant conversation into a delightful duet. Although failure to align is sometimes associated with discord, exploring divergent opinions can also foster understanding and agreement, satisfy curiosity, and spur imagination. Using fMRI hyperscanning and natural language processing, we tested if dyadic alignment or exploration during decision-making conversations was a more effective route to agreement. Dyads (N = 60) discussed pressing societal problems while being instructed to either persuade or compromise with their partner. Our analysis uncovered four key insights: First, individuals instructed to compromise rather than persuade tended to agree more at the end of the conversation. Second, hyperscanning and linguistic analyses revealed that encouraging compromise resulted in increased exploration during conversations; dyads given compromise instructions traversed more diverse mental states and topics. Third, heightened exploration was linked to greater agreement at the end of the conversation. Fourth, the effect of the compromise instructions on agreement was entirely mediated by the degree of exploration. Together, these results suggest that finding agreement may be spurred by exploration, something that happens spontaneously when people are motivated to compromise. Significance StatementSuccessful conflict resolution is not just about syncing perfectly--it sometimes means leaning into differences. Our study employed fMRI hyperscanning to examine if exploratory conversation strategies promote consensus. We paired participants to discuss societal issues with either a persuasion or compromise mindset. We found that dyads aiming to compromise reached more agreement because they delved deeper into each others minds and covered more topics; in contrast, dyads aiming to persuade their partner covered a narrower scope of topics and mental states and ended up disagreeing more as a result. The finding that exploration rather than simple alignment facilitates agreement could sharpen communication strategies in fields from politics to education and economics.

neuroscience↗

bioRxiv2022

Conscientiousness associated with efficiency of the salience/ventral attention network: Replication in three samples using individualized parcellation

Previous research in the field of personality neuroscience has identified associations of conscientiousness and related constructs like impulsivity and self-control with structural and functional properties of particular regions in the prefrontal cortex (PFC) and insula. Network- based conceptions of brain function suggest that these regions probably belong to a single large- scale network, labeled the salience/ventral attention network (SVAN). The current study tested associations between conscientiousness and resting-state functional connectivity in this network using two community samples (N = 244 and 239) and data from the Human Connectome Project (N = 1000). Individualized parcellation was used to improve the accuracy of functional localization and to facilitate replication. Functional connectivity was measured using an index of network efficiency, a graph theoretical measure quantifying the capacity for parallel information transfer within a network. Efficiency of a set of parcels in the SVAN was significantly associated with conscientiousness in all samples. Findings are consistent with a theory of conscientiousness as a function of variation in neural networks underlying effective prioritization of goals.

neuroscience↗

bioRxiv2021

Functional architecture of the aging brain

The intrinsic functional organization of the brain changes into older adulthood. Age differences are observed at multiple spatial scales, from global reductions in modularity and segregation of distributed brain systems, to network-specific patterns of dedifferentiation. Whether dedifferentiation reflects an inevitable, global shift in brain function with age, circumscribed, experience dependent changes, or both, is uncertain. We employed a multi-method strategy to interrogate dedifferentiation at multiple spatial scales. Multi-echo (ME) resting-state fMRI was collected in younger (n=181) and older (n=120) healthy adults. Cortical parcellation sensitive to individual variation was implemented for precision functional mapping of each participant, while preserving group-level parcel and network labels. ME-fMRI processing and gradient mapping identified global and macroscale network differences. Multivariate functional connectivity methods tested for microscale, edge-level differences. Older adults had lower BOLD signal dimensionality, consistent with global network dedifferentiation. Gradients were largely age-invariant. Edge-level analyses revealed discrete, network-specific dedifferentiation patterns in older adults. Visual and somatosensory regions were more integrated within the functional connectome; default and frontoparietal control network regions showed greater connectivity; and the dorsal attention network was more integrated with heteromodal regions. These findings highlight the importance of multi-scale, multi-method approaches to characterize the architecture of functional brain aging.

neuroscience↗