A high-performance speech neuroprosthesis

Nature, Journal Year: 2023, Volume and Issue: 620(7976), P. 1031 - 1036

Published: Aug. 23, 2023

Speech brain-computer interfaces (BCIs) have the potential to restore rapid communication people with paralysis by decoding neural activity evoked attempted speech into text

Language: Английский

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Imagined speech can be decoded from low- and cross-frequency intracranial EEG features

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Jan. 10, 2022

Reconstructing intended speech from neural activity using brain-computer interfaces holds great promises for people with severe production deficits. While decoding overt has progressed, imagined met limited success, mainly because the associated signals are weak and variable compared to speech, hence difficult decode by learning algorithms. We obtained three electrocorticography datasets 13 patients, electrodes implanted epilepsy evaluation, who performed tasks. Based on recent theories of processing, we extracted consistent specific features usable future brain computer interfaces, assessed their performance discriminate items in articulatory, phonetic, vocalic representation spaces. high-frequency provided best signal both low- higher-frequency power local cross-frequency contributed decoding, particular phonetic vocalic, i.e. perceptual, These findings show that low-frequency dynamics contain key information decoding.

Language: Английский

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Recovery from aphasia in the first year after stroke

Brain, Journal Year: 2022, Volume and Issue: 146(3), P. 1021 - 1039

Published: April 7, 2022

Most individuals who experience aphasia after a stroke recover to some extent, with the majority of gains taking place in first year. The nature and time course this recovery process is only partially understood, especially its dependence on lesion location which are most important determinants outcome. aim study was provide comprehensive description patterns from year stroke. We recruited 334 patients acute left hemisphere supratentorial ischaemic or haemorrhagic evaluated their speech language function within 5 days using Quick Aphasia Battery (QAB). At initial point, 218 presented aphasia. Individuals were followed longitudinally, follow-up evaluations at 1 month, 3 months, post-stroke, wherever possible. Lesions manually delineated based clinical MRI CT imaging. Patients without divided into 13 groups similar, commonly occurring brain damage. Trajectories then investigated as group (i.e. extent) speech/language domain (overall function, word comprehension, sentence finding, grammatical construction, phonological encoding, motor programming, execution, reading). found that dynamic, multidimensional, gradated, little explanatory role for subtypes binary concepts such fluency. circumscribed frontal lesions recovered well, consistent previous observations. More surprisingly, larger extending parietal temporal lobes also did relatively temporal, temporoparietal, lesions. Persistent moderate severe deficits common extensive damage throughout middle cerebral artery distribution temporoparietal There striking differences between domains rates relationships overall suggesting specific differ extent they redundantly represented network, opposed depending specialized cortical substrates. Our findings have an immediate application will enable clinicians estimate likely individual patients, well uncertainty these predictions, acutely observable neurological factors.

Language: Английский

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Post-stroke outcomes predicted from multivariate lesion-behaviour and lesion network mapping

Brain, Journal Year: 2022, Volume and Issue: 145(4), P. 1338 - 1353

Published: Jan. 10, 2022

Abstract Clinicians and scientists alike have long sought to predict the course severity of chronic post-stroke cognitive motor outcomes, as ability do so would inform treatment rehabilitation strategies. However, it remains difficult make accurate predictions about outcomes due, in large part, high inter-individual variability recovery a reliance on clinical heuristics rather than empirical methods. The neuroanatomical location stroke is key variable associated with long-term because lesion can be derived from routinely collected neuroimaging data there an opportunity use this information empirically based deficits. For example, compared statistically weighted multivariate lesion-behaviour maps regions that, when damaged, are specific deficits aggregated outcome cohorts. Here, our goal was evaluate whether we leverage two cohorts individuals focal brain lesions 12-month independent sample patients. Further, evaluated could augment these by estimating structural functional networks disrupted association each map through network mapping, which normative connectivity neurologically healthy elucidate lesion-associated networks. We using anatomical strongest impairment for results. These peak regional findings became ‘seeds’ generate networks, approach that offers potentially greater precision previously used single-lesion approaches. Next, sample, quantified overlap mapping how much variance explain behavioural latent growth curve statistical model. found lesion-deficit modality able significant amount outcomes. Both were beyond mapping. Functional performed best prediction language deficits, Altogether, results support notion combined improve at 12-months.

Language: Английский

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Population-based tract-to-region connectome of the human brain and its hierarchical topology

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Aug. 22, 2022

Abstract Connectome maps region-to-region connectivities but does not inform which white matter pathways form the connections. Here we constructed a population-based tract-to-region connectome to fill this information gap. The quantifies population probability of tract innervating cortical region. results show that ~85% entries are consistent across individuals, whereas remaining (~15%) have substantial individual differences requiring individualized mapping. Further hierarchical clustering on regions revealed dorsal, ventral, and limbic networks based connective patterns. bundles categorization fiber bundle systems in association pathways. This provides insights into topology between bundles. derived relation further offers gray structures.

Language: Английский

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A Neurosurgical Functional Dissection of the Middle Precentral Gyrus during Speech Production

Journal of Neuroscience, Journal Year: 2022, Volume and Issue: 42(45), P. 8416 - 8426

Published: Nov. 9, 2022

Classical models have traditionally focused on the left posterior inferior frontal gyrus (Broca's area) as a key region for motor planning of speech production. However, converging evidence suggests that it is not critical either or execution. Alternative cortical areas supporting high-level yet to be defined. In this review, we focus precentral gyrus, whose role in production often thought limited lower-level articulatory muscle control. particular, highlight neurosurgical investigations shed light anatomically located near midpoint hence called middle (midPrCG). The midPrCG functionally between dorsal hand and ventral orofacial representations exhibits unique sensorimotor multisensory functions relevant processing. This includes control larynx, auditory processing, well reading writing. Furthermore, direct electrical stimulation can evoke complex movements, such vocalization, selective injury cause deficits verbal fluency, pure apraxia speech. Based these findings, propose essential phonological-motoric aspects production, especially syllabic-level sequencing, ascribed Broca's area. brain area should included contemporary with

Language: Английский

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Functional Contributions of the Arcuate Fasciculus to Language Processing

Frontiers in Human Neuroscience, Journal Year: 2021, Volume and Issue: 15

Published: June 25, 2021

Current evidence strongly suggests that the arcuate fasciculus (AF) is critical for language, from spontaneous speech and word retrieval to repetition comprehension abilities. However, further pinpoint its unique differential role in anatomy needs be explored greater detail contribution language processing beyond of known cortical areas must established. We address this a comprehensive evaluation specific functional AF well-characterized cohort individuals with chronic aphasia (n = 33) following left hemisphere stroke. To evaluate macro- microstructural integrity AF, tractography based on constrained spherical deconvolution model was performed. The right hemispheres were then manually reconstructed using modified 3-segment (Catani et al., 2005), 2-segment (Glasser Rilling, 2008). normalized volume measure long posterior segments significantly correlated indices while controlling gender lesion volume. Specific contributions accounting - inferior frontal, parietal, temporal tested multiple regression analyses. Involvement tract demonstrated: segment contributed naming abilities; anterior fluency naming; comprehension. results highlight important fiber pathways impairments areas. At same time, no clear tracts could ascertained. In sum, our findings lend support broader processing, particular emphasis naming, point as being most crucial supporting residual

Language: Английский

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The human language effective connectome

NeuroImage, Journal Year: 2022, Volume and Issue: 258, P. 119352 - 119352

Published: June 2, 2022

To advance understanding of brain networks involved in language, the effective connectivity between 26 cortical regions implicated language by a community analysis and 360 was measured 171 humans from Human Connectome Project, complemented with functional diffusion tractography, all using HCP multimodal parcellation atlas. A (semantic) network (Group 1) involving inferior superior temporal sulcus cortex (STS) adjacent visual TE1a pole TG, connected parietal PGi region, has (TE) regions; PFm which also connectivity; posterior cingulate memory-related frontal pole, orbitofrontal cortex, medial prefrontal cortex; dorsolateral 44 45 for output regions. It is proposed that this system can build its lobe (STS TG) parts (PGi PGs) semantic representations objects incorporating especially their reward properties. Another 3) more including STGa, auditory A5, TPOJ1, STV Peri-Sylvian Language area (PSL) areas (A1, A4, Pbelt); relatively early motion, e.g., MT MST, faces/words (FFC); somatosensory (frontal opercular FOP, insula PF); other TPOJ gyrus (IFJa IFSp). builds specialising related facial motion information useful theory mind / body image information, outputs directed not only to 45, but premotor 55b midcingulate cortex. Both (Groups 1 have access hippocampal episodic memory via parahippocampal TF. third largely 2) (44, 47l; 55b; Superior Frontal region SFL; TGv) receives two systems, syntax speech output.

Language: Английский

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What is Functional Communication? A Theoretical Framework for Real-World Communication Applied to Aphasia Rehabilitation

Neuropsychology Review, Journal Year: 2022, Volume and Issue: 32(4), P. 937 - 973

Published: Jan. 25, 2022

Abstract Aphasia is an impairment of language caused by acquired brain damage such as stroke or traumatic injury, that affects a person’s ability to communicate effectively. The aim rehabilitation in aphasia improve everyday communication, improving individual’s function their day-to-day life. For reason, thorough understanding naturalistic communication and its underlying mechanisms imperative. field aphasiology currently lacks agreed, comprehensive, theoretically founded definition communication. Instead, multiple disparate interpretations functional are used. We argue this makes it nearly impossible validly reliably assess communicative performance, target behaviour through therapy, measure improvements post-therapy. In article we propose structured, theoretical approach defining the concept for view “situated use”, borrowed from empirical psycholinguistic studies with non-brain damaged adults. This framework defines use as: (1) interactive, (2) multimodal, (3) contextual. Existing research on each component adults people reviewed. consequences adopting assessment therapy discussed. encourage more systematic, comprehensive study treatment situated aphasia.

Language: Английский

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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

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