Biology subjects

Tabasi, F.

Publications and source records attributed to Tabasi, F..

4 recordsLinked to original sources

bioRxiv2026

A domain-general basal ganglia mechanism for inhibitory control during language comprehension

Whether controlled language processing involves domain-general or language-specific neural circuits is subject of controversial debate. We tested whether the inhibitory control of linguistic activity shares a common neural process with motor inhibition in twenty humans undergoing intra- and extracranial neural field potential recordings and deep-brain stimulation. Engaging motor and linguistic inhibition simultaneously resulted in a significant behavioral cost, suggesting a shared underlying neural process. Indeed, neural decoders trained during motor inhibition were able to decode linguistic inhibition and vice versa. Depth-electrode recordings from the subthalamic nucleus (STN), a key basal ganglia area for inhibitory control, showed increased {beta}-band (13-30 Hz) activity during both linguistic and motor inhibition. Finally, disrupting the STN via deep-brain stimulation impaired behavioral and neural signatures of both linguistic and motor inhibition. Together, these findings show that the inhibitory control of language and movement share a domain-general mechanism implemented via the subthalamic nucleus of the basal ganglia.

neuroscience↗

bioRxiv2025

Neural activity flows through cortical subnetworks during speech production

Speech production entails several processing steps that encode linguistic and articulatory structure, but whether these computations correspond to spatiotemporally discrete patterns of neural activity is unclear. To address this issue, we used electrocorticography to directly measure the brains of neurosurgical participants performing an interactive speech paradigm. We observed a broad range of cortical modulation profiles, and subsequent clustering analyses established that responses comprised distinct classes associated with sensory perception, planning, motor execution, and task-related suppression. These activity classes were also localized to separate neural substrates, indicating their status as specialized networks. We then parsed dynamics in the planning and motor networks using unsupervised dimensionality reduction, which revealed subnetworks that were sequentially active throughout preparation and articulation. These results therefore support and extend a localizationist model of speech production where cortical activity flows within and across discrete pathways during language use.

neuroscience↗

bioRxiv2024

Sex and Region-Specific Disruption of Autophagy and Mitophagy in Alzheimer's Disease: Linking Cellular Dysfunction to Cognitive Decline

Macroautophagy and mitophagy are critical processes in Alzheimers disease (AD), yet their links to behavioral outcomes, particularly sex-specific differences, are not fully understood. This study investigates autophagy (LC3B-II, SQSTM1) and mitophagy (BNIP3L, BNIP3, BCL2L13) markers in the cortex and hippocampus of male and female 3xTg-AD mice, using western blotting, transmission electron microscopy (TEM), and behavioral tests (novel object recognition and novel object placement). Significant sex-specific differences emerged: female 3xTg-AD mice exhibited autophagosome accumulation due to impaired degradation in the cortex, while males showed fewer autophagosomes, especially in the hippocampus, without significant degradation changes. TEM analyses demonstrated variations in mitochondrial and mitophagosome numbers correlated with memory outcomes. Females had enhanced mitophagy, with higher BNIP3L and BCL2L13 levels, whereas males showed elevated BNIP3 dimers. Cognitive deficits in females correlated with mitochondrial dysfunction in the cortex, while in males, higher LC3B-II levels associated positively with cognitive performance, suggesting protective autophagy effects. Using machine learning, we predicted mitophagosome and mitochondrial numbers based on behavioral data, pioneering a predictive approach to cellular outcomes in AD. These findings underscore the importance of sex-specific regulation of autophagy and mitophagy in AD and support personalized therapeutic approaches targeting these pathways. Integrating machine learning emphasizes its potential to advance neurodegenerative research. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=109 SRC="FIGDIR/small/621097v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@1e50ceeorg.highwire.dtl.DTLVardef@b41ac0org.highwire.dtl.DTLVardef@4863d3org.highwire.dtl.DTLVardef@91b2d0_HPS_FORMAT_FIGEXP M_FIG C_FIG Graphical AbstractSex-specific differences in autophagy and mitophagy regulation in Alzheimers disease (AD) are highlighted. Female 3xTg-AD mice show autophagosome accumulation and cognitive deficits, while males exhibit variations in mitophagy markers and behavior.

neuroscience↗

bioRxiv2023

Identifying critical language planning regions with direct electrical brain stimulation

Many brain areas exhibit activity correlated with language planning1-9, but the impact of these dynamics on spoken interaction remains unclear. Here we use direct electrical stimulation to transiently perturb cortical function in neurosurgical patient-volunteers performing a question-answer task10. Stimulating structures involved in speech motor function evoked diverse articulatory deficits, while perturbations of caudal inferior and middle frontal gyri - which exhibit preparatory activity during conversational turn-taking - led to response errors. Perturbation of the same planning-related frontal regions slowed inter-speaker timing, while faster responses could result from stimulation of sites located in other areas. Taken together, these findings further indicate that caudal inferior and middle frontal gyri constitute a critical planning network essential for interactive language use1.

neuroscience↗