The emergent properties of the connected brain

Science, Journal Year: 2022, Volume and Issue: 378(6619), P. 505 - 510

Published: Nov. 3, 2022

There is more to brain connections than the mere transfer of signals between regions. Behavior and cognition emerge through cortical area interaction. This requires integration local distant areas orchestrated by densely connected networks. Brain determine brain's functional organization. The imaging in living has provided an opportunity identify driving factors behind neurobiology cognition. Connectivity differences species among humans have furthered understanding evolution diverging cognitive profiles. pathologies amplify this variability disconnections and, consequently, disintegration functions. prediction long-term symptoms now preferentially based on disconnections. paradigm shift will reshape our maps challenge current models.

Language: Английский

---

EEGpower spectral measures of cognitive workload: A meta‐analysis

Psychophysiology, Journal Year: 2022, Volume and Issue: 59(6)

Published: Feb. 6, 2022

Abstract Cognitive workload (CWL) is a fundamental concept in the assessment and monitoring of human performance during cognitive tasks. Numerous studies have attempted to objectively continuously measure CWL using neuroimaging techniques. Although electroencephalogram (EEG) widely used technique, impact on spectral power brain frequencies has shown inconsistent results. The present review aimed synthesize results literature quantitatively assess which frequency most sensitive CWL. A systematic search following PRISMA recommendations highlighted three main bands CWL: theta (4–8 Hz), alpha (8–12 beta (12–30 Hz). Three meta‐analyses were conducted examine effect these frequencies. total 45 sizes from 24 involving 723 participants computed. was associated with significant effects ( g = 0.68, CI [0.41, 0.95]), −0.25, [−0.45, 0.04]), 0.50, [0.21, 0.79]) power. Our suggests that theta, especially frontal best index Alpha also significantly impacted by CWL; however, their association seemed less straightforward. These are critically analyzed considering cerebral oscillations. We conclude emphasizing need investigate interaction between other factors may influence (e.g., emotional load), combine this methods analysis central peripheral nervous system functional connectivity, heart rate).

Language: Английский

---

Controversy over the temporal cortical terminations of the left arcuate fasciculus: a reappraisal

Brain, Journal Year: 2022, Volume and Issue: 145(4), P. 1242 - 1256

Published: Feb. 8, 2022

The arcuate fasciculus has been considered a major dorsal fronto-temporal white matter pathway linking frontal language production regions with auditory perception in the superior temporal gyrus, so-called Wernicke's area. In line this tradition, both historical and contemporary models of function have assigned primacy to projections fasciculus. However, classical anatomical descriptions emerging behavioural data are at odds assumption. On one hand, area may not be unique other stream deficits reported also for damage middle, inferior basal gyri that linked disconnection. These findings point reappraisal lobe. Here, we review functional evidence regarding cortical terminations left by incorporating dissection tractography stimulation using cortico-cortical evoked potentials direct electrical mapping awake patients. First, discuss fibres projecting gyrus rostro-caudal gradient region where phonological encoding auditory-motor transformation performed. Caudal within temporoparietal junction involved articulation associated third branch longitudinal fasciculus, while more rostral support acoustic phonetic features, supported fibres. We then move examine clinical showing multimodal is facilitated superior, but regions. Hence, how contribute (middle-posterior middle gyri), visual (posterior temporal/fusiform comprising word form area) lexical (anterior-middle information lobe processed, encoded translated into route Finally, out surgical implications model terms prediction avoidance neurological deficit.

Language: Английский

---

New Philosophy, Clinical Pearls, and Methods for Intraoperative Cognition Mapping and Monitoring “à la carte” in Brain Tumor Patients

Neurosurgery, Journal Year: 2020, Volume and Issue: 88(5), P. 919 - 930

Published: July 22, 2020

Abstract The purpose of surgery for brain tumors involving eloquent neural circuits is to maximize the extent resection while preserving an optimal quality life. To this end, especially in diffuse glioma, goal remove cerebral parenchyma invaded by neoplasm up individual cortico-subcortical networks critical functions. Intraoperative mapping combined with real-time cognitive monitoring throughout awake patient thus highly recommended resume a normal Indeed, beyond avoiding hemiplegia or aphasia, enjoying familial, social, and professional life implies that motor language not sufficient. Identifying sparing subserve cognition (movement control, visuospatial cognition, executive functions, multimodal semantics, metacognition) mentalizing (theory mind, which plays key role social cognition) essential preserve adapted behavior. Here, aim review when how map these have nonetheless been neglected many decades neurosurgeons. In fact, disorders generated surgical injuries underpinning nonmotor nonspeech functions are usually immediately visible on postoperative standard clinical examination, leading physician believe has no deficit. Yet, emotional disturbances may subsequently prevent active life, as work full time. Therefore, systematic neuropsychological assessment should be performed before, during, after mapping-guided surgery, regardless tumor location, functional connectome intraoperatively plan tailored rehabilitation according patient's needs.

Language: Английский

---

Functional Mapping before and after Low-Grade Glioma Surgery: A New Way to Decipher Various Spatiotemporal Patterns of Individual Neuroplastic Potential in Brain Tumor Patients

Cancers, Journal Year: 2020, Volume and Issue: 12(9), P. 2611 - 2611

Published: Sept. 13, 2020

Intraoperative direct electrostimulation mapping (DEM) is currently the gold-standard for glioma surgery, since functional-based resection allows an optimization of onco-functional balance (increased with preserved quality life). Besides intrasurgical awake conation, cognition, and behavior, preoperative by means functional neuroimaging (FNI) transcranial magnetic stimulation (TMS) has increasingly been utilized surgical selection planning. However, because these techniques suffer from several limitations, particularly subcortical white matter pathways, DEM remains crucial to map neural connectivity. On other hand, non-invasive FNI TMS can be repeated before after resection(s), enabling longitudinal investigation brain reorganization, especially in slow-growing tumors like low-grade gliomas. Indeed, neoplasms generate neuroplastic phenomena patients usually no or only slight neurological deficits at diagnosis, despite gliomas involving so-called “eloquent” structures. Here, data gained perioperative FNI/TMS methods are reviewed, order decipher mechanisms underpinning cerebral reshaping induced tumor its possible relapse, (re)operation(s), postoperative rehabilitation. Heterogeneous spatiotemporal patterns rearrangement across a single patient over time have evidenced, structural changes as well modifications intra-hemispheric (in ipsi-lesional and/or contra-lesional hemisphere) inter-hemispheric Such various fingerprints reconfiguration were correlated different levels cognitive compensation. Serial multimodal studies exploring neuroplasticity might lead new management strategies based upon multistage therapeutic approaches adapted individual profile reallocation.

Language: Английский

---

Brain connectomics applied to oncological neuroscience: from a traditional surgical strategy focusing on glioma topography to a meta-network approach

Acta Neurochirurgica, Journal Year: 2021, Volume and Issue: 163(4), P. 905 - 917

Published: Feb. 9, 2021

Language: Английский

---

Missing links: The functional unification of language and memory (L∪M)

Neuroscience & Biobehavioral Reviews, Journal Year: 2021, Volume and Issue: 133, P. 104489 - 104489

Published: Dec. 17, 2021

The field of neurocognition is currently undergoing a significant change perspective. Traditional neurocognitive models evolved into an integrative and dynamic vision cognitive functioning. Dynamic integration assumes interaction between domains traditionally considered to be distinct. Language declarative memory are regarded as separate functions supported by different neural systems. However, they also share anatomical structures (notably, the inferior frontal gyrus, supplementary motor area, superior middle temporal hippocampal complex) processes (such semantic working memory) that merge endorse our quintessential daily lives. We propose new model, "L∪M" (i.e., Language/union/Memory), considers these two interactively. fractionated language three fundamental dimensions or systems ("Receiver-Transmitter", "Controller-Manager" "Transformer-Associative" Systems), communicate reciprocally. formalized their interactions at brain level with connectivity-based approach. This taxonomy overcomes modular view functioning reconciles functional specialization plasticity in neurological disorders.

Language: Английский

---

Understanding Language Reorganization With Neuroimaging: How Language Adapts to Different Focal Lesions and Insights Into Clinical Applications

Frontiers in Human Neuroscience, Journal Year: 2022, Volume and Issue: 16

Published: Feb. 18, 2022

When the language-dominant hemisphere is damaged by a focal lesion, brain may reorganize language network through functional and structural changes known as adaptive plasticity. Adaptive plasticity documented for triggers including ischemic, tumoral, epileptic lesions, with effects in clinical practice. Many questions remain regarding Different lesions induce different patterns of reorganization depending on pathologic features, location brain, timing onset. Neuroimaging provides insights into due to its non-invasiveness, ability image whole large-scale implementation. This review an overview MRI patient care. First, we describe depicted neuroimaging. Second, explore triggered stroke, tumors, analyze applications diagnosis treatment planning. By comparing investigate determinants lesion onset, longitudinal evolution reorganization, relationship between changes.

Language: Английский

---

White matter tracts and executive functions: a review of causal and correlation evidence

Brain, Journal Year: 2023, Volume and Issue: unknown

Published: Sept. 11, 2023

Executive functions are high-level cognitive processes involving abilities such as working memory/updating, set-shifting and inhibition. These complex enabled by interactions among widely distributed networks, supported white matter tracts. impairment is frequent in neurological conditions affecting matter; however, whether specific tracts crucial for normal executive unclear. We review causal correlation evidence from studies that used direct electrical stimulation during awake surgery gliomas, voxel-based tract-based lesion-symptom mapping, diffusion tensor imaging to explore associations between the integrity of healthy impaired adults. The corpus callosum was consistently associated with all processes, notably its anterior segments. Both showed prominent support superior longitudinal fasciculus functions, memory. More specifically, strong suggested second branch especially flexibility. Global results left lateralization verbal tasks right visual demands. frontal aslant tract potentially supports additional needed clarify involvement goes beyond control language. Converging indicates a right-lateralized network connecting cortical subcortical grey regions performance assessing response inhibition, some suggesting role thalamic radiation. Finally, suggests cingulum bundle discuss these findings light current knowledge about functional tracts, descriptions brain networks supporting clinical implications individuals tumours.

Language: Английский

---

The domain-separation language network dynamics in resting state support its flexible functional segregation and integration during language and speech processing

NeuroImage, Journal Year: 2023, Volume and Issue: 274, P. 120132 - 120132

Published: April 25, 2023

Modern linguistic theories and network science propose that language speech processing are organized into hierarchical, segregated large-scale subnetworks, with a core of dorsal (phonological) stream ventral (semantic) stream. The two streams asymmetrically recruited in receptive expressive or tasks, which showed flexible functional segregation integration. We hypothesized the was supported by underlying segregation. A dynamic conditional correlation approach employed to construct framewise time-varying networks k-means clustering investigate temporal-reoccurring patterns. found dynamics resting state were robustly clustered four states, dynamically reconfigured following domain-separation manner. Spatially, hub distributions first three states highly resembled neurobiology perception lexical-phonological processing, production, semantic respectively. fourth characterized weakest connectivity regarded as baseline state. Temporally, appeared exclusively limited time bins (∼15%), most (> 55%), 4 dominant. Machine learning-based dFC-linguistics prediction analyses dFCs significantly predicted individual performance. These findings suggest manner state, forms "meta-network" framework support integration during processing.

Language: Английский

---