The physiology of stroke neurorehabilitation

The Journal of Physiology, Journal Year: 2025, Volume and Issue: 603(3), P. 611 - 615

Published: Jan. 21, 2025

The Cochrane network, in its definition of rehabilitation, refers to "interventions targeting a person's" capacity (by addressing body structures, functions, and activities/participation) … with the goal "optimizing" "functioning" "persons health conditions currently experiencing disability or likely experience …" (Negrini et al., 2022). In respect significance accorded 'capacity' 'functioning', rehabilitation lies squarely within purview physiology, emphasis on integration molecular, cellular, systems whole-body function. Neurorehabilitation (a.k.a. neurological rehabilitation) deals more specifically (e.g. National Institute for Health & Care Excellence, 2021) impairments that arise from injury brain, spine peripheral nerves, caused by disease, trauma, tumours, infections, metabolic insults disorders blood supply – such as stroke. terms ramifications, stroke ranks second highest cause death (Roth 2018), follows only neonatal ischaemic heart disease an agent long-term (Kyu 2018). Most notably, has impact severity, greater than any other chronic Adamson 2004). It is estimated approximately 15 million strokes occur worldwide every year (World Organization, 2024). Of those who survive, half will be left demands neurorehabilitation. With lethality falling, incidence rising especially low-income middle-income countries (Prust 2024), there renewed imperative direct research towards life after stroke, particularly since targets neurorehabilitation feature prominently among priorities identified survivors their carers (Pollock 2012). seems self-evident physiological knowledge should inform neurorehabilitation, when aspiration increase efficacy efficiency delivery. this context, might extend mechanisms mediate adaptation to, recovery from, brain damage. may also encompass means through which technique exerts effect. Writing collection, Carson Hayward (2025) point out these strands are integrated less frequently one suppose. addition, unlike many areas clinical science, relevant physiology sought (if at all) following concoction novel therapy, rather precursor. Perhaps due lack appreciation existing corpus directly This special issue Journal Physiology been devised aim highlighting recent empirical contributions corpus, along key theoretical concepts information can parsed. Many features responses observed tissue (and beyond) haemorrhagic have deeply characterised cellular levels, primarily using animal models. Especially salient context relationships exist between specific sequelae acute effects functions human nervous system. describing pathophysiology post-stroke dysphagia (PSD), Sasegbon al. emphasise understand PSD, it first necessary comprehend neurophysiology swallowing humans. complex involve dynamic interplay control centres defined level brainstem, well higher cerebellum cerebral cortices. Damage element distributed network result discoordination oropharyngeal oesophageal muscles otherwise engaged precise sequence safely convey ingested material oral cavity stomach. Yet, highlight, our interactions give rise requisite muscle synergies remains incomplete. Consequentially, not yet possible determine whether subcortical lesions arises damage centres, alterations connectivity cortical centres. gap understanding reflects general tension long-standing view functional deficits grey matter 'hub regions' (i.e. loci), increasingly influential conception 'circuitopathy' (Cassidy 2022), whereby magnitude white determines severity capacity. regard, Urbin draws attention observation macro-level typically lower threshold infarction matter. highlight findings integrity structural (brain) connectome preeminent factor determining extent motor function occurs weeks Structural disconnection seen exert causal influence (on capacity) disruption circuits tracts afford. support position, they review observations 'cross-road' regions comprising several expressed span multiple domains memory spatial memory, attention, motor, language). upper limb, long recognised (constituting 'projectome') efferent commands spinal neurons profound degree movement preserved Much contemporary discourse has, however, exclusive focus fibres corticospinal tract. exhaustive review, rich detailed analysis neuroanatomy, reminds us neural impulses goal-directed conveyed single Rather, keeping notion 'volitional set' Gottlieb, 1996), corticospinal-mediated changes excitability motoneurons shaped descending segmental pathways. Neuroanatomy further dictates rarely affects tract, heterogeneity distribution sustained across accounting least some variation impairment loss exhibited individuals (Urbin, 2025). nature imposes especial challenges forecast outcomes individual patients. Undertaken subacute stage, presence absence motor-evoked potentials (MEPs) contralateral delivery transcranial magnetic stimulation (TMS) scalp locations overlying primary cortex, offers promise biomarker limb Due various pathways (other tract) post-synaptic state motoneurons, MEPs cannot simply interpreted indicative tract integrity. does not, diminish potential utility MEPS, provide broadly encompassing measure corticomotor access final common pathway preserved. issue, Shanks Byblow argue binary MEP outcome (present absent) hitherto used biomarker, fail fully exploit prognostic power potentials. because criterion applied present arbitrary amplitude value 50 µV). As out, sub-threshold contain appraisal impairment, recovery. extension refinement approach, advocate use TMS-evoked obtained simultaneously wide range intensities. Three classes response designated: (1) meet conventional deemed 'present'; (2) below ordinarily (in scheme) marked 'absent'; (3) instances which, given muscle, intensity fails elicit MEP. resulting 'threshold matrix', subject compositional data analysis, represented ternary plot. Beyond providing granular status, phase during attenuated absent, hypothesise sub-regions plot differentiate phenotypes. A challenge determination optimal basis upon phenotypes recovery) defined. wide-ranging fatigue, Kuppuswamy argues presently unknown derived class variable perceptual/behavioural/neuronal), composite types. Although evidently broad significance, question relation fatigue. Divination answer is, hampered multidimensional fatigue symptomology, transcends paradigms assessment. Arguing that, fundamentally, 'fatigue' perceptual experience, makes case systematisation phenotyping precursor, firstly, enhanced pathophysiology, secondly, development effective treatments. While necessarily, multiplicity engenders manifestation models ground process beginning emerge. Analysing merits models, 'sensory attenuation model' dysfunction, provides promising account diverse phenomenology particular mediating altered attentional processes. model complementary conceptions apathy (described Hayward, 2025) diffuse cerebrovascular pathology impairs large-scale networks underpin control, reinforcement learning reward-based decision-making. theme emerge again, concept 'neuroplasticity' underpins much conducted domain fired popular imagination, works Brain That Changes Itself (Doidge, 2007). supposition instilled most vivid portrayals neuroplasticity, 'endless adaptability' (Sacks, An allied conjecture 'reorganisation' idea take new (for critical discussion see Makin Krakauer, 2023). inspirational studies notwithstanding, considerations evidence indicate, instead, neuroplastic adaptations already 'representational computational capacity' compromised. 'structural blueprint' system strong constraints realisable (Makin notes even cases severe paresis tends preservation brainstem origin course carry neuron pools. Rehabilitating therefore involves certain reintegration supraspinal circuits, vascular insult restricted former. Focussing neuraxis transmission tracts, study transneuronal degeneration regeneration) cord 'poor cousin' concerns itself infarcts circuits. 'Downstream' 'upstream' can, levels These include segregation into origins frontal parietal areas, funiculi terminations lumbar cervical segments, pools ventral horn Importantly, remain viable responsive excitation regardless identity fibre considerable period cells deprived usual trophic inputs. remarks, 'restoring about forming extensively circuitry altering substrate remains'. comprehensive focussing experience-driven competition reorganisation Jones emphasises under consideration, fundamental assumption regenerative reactions activity-dependent. practice tenet equivalent status behavioural interventions activity patterns manner promotes reactions. resides principles guide design interventions. Drawing work undertaken rodent seeks delineate permit identified, generalise populations. consistent experimentally induced cortex rodents de novo skill performed non-paretic forelimb interfere rehabilitative training engender improvements paretic paw. implication new-experience dependent performance paw disruptive (Jones, At glance, appear run counter impaired (discussed Kitchen 2025 (through 'cross education' effect) bring limb. detrimental consequences arising counteracted bimanual training, interleaving limbs. To echo raised (2025), determined whether, patients, schedule alternating engagement delineating molecular processes remodelling overstated, (which occupies bulk (Ebbesen Brecht, 2017)) very rare humans (van Assche 2021). interest additional yield convergent role both hemispheres promoting presumption endogenous CNS augmented neurons. employed engendering non-invasively (see 2025), current (tDCS) variants repetitive TMS (rTMS). balance available Ahmed 2023) protocols designed ipsilesional hemisphere efficacy, whereas intention decreasing contralesional limited meta-analysis (Ahmed indicated positive transcutaneous vagus nerve (VNS) exceeded physical alone outranked all forms non-invasive stimulation, measures activities daily living. contribution Schambra Hays survey foundational VNS therapy. They optimally mechanistic acts network. underlined probably different ascribed tDCS rTMS. large 'paired therapy' lends weight assertion. Applied non-invasively, administered ('open loop') (usually limb). paired VNS, bursts electrical delivered via implanted electrodes, intervals relative movements made 'closed loop' arrangement. Detailed profiling form supports triggers widespread release neuromodulatory neurotransmitters (including noradrenaline, serotonin acetylcholine), alters synapses generation movement) activated recently. Timing critical. Delivered 2 s event, experimental indices gains. If, hand, delay 10 s, no (Schambra Hays, There observation. When preclinical employed, traces synaptic differ depending spared injury. instrumental drive practical delivering electrode specificity suggests accommodate life-threatening event requiring urgent medical assistance care hospital, public education campaigns rightly urge vigilance manifestations. example, Service UK includes cardinal sign: 'weakness numbness down 1 side your body'. Medical textbooks too Torbey Selim, 2013), put unilateral expression symptoms. vein also, scientific literature replete articles draw contrast 'impaired limb' 'non-impaired limb'. tendency thus conceive body. Surveying garnered over decades, sometimes subtle, but definitively systematic, arm follow hemispheric specialisation selective demonstrated arms contingent injured. Expressed language dominance hypothesis (Sainburg, 2002, 2005), right-handed individuals) contains 'tuned' facilitate dynamics. Whereas right adapted regulation impedance. corollary while differentiation revealed clearly (the characteristics of) arm, local each play ipsilateral (Kitchen Consistent model, show early reaching misspecification initial direction), often achieving accurate position contrast, suffered commonly exhibit abnormalities decelerative accentuated errors positioning What more, appears closely related New strategies paresis) advanced remediate hemisphere-specific reader note convergence outworking approaches driven cross-education. Remaining way generated tests therapeutic phenomenon cross-education (Calvert Carson, 2022; lateralisation became functionally adaptive, i.e. phylogenetic sense, presumably evolved neuroanatomical structures capable supporting two hemispheres. Integration counterpart (hemispheric) specialisation. Accordingly, appraised callosum largest connecting hemispheres, significant bearing scope subsequent 2020). important future disconnectome modelling delineated scan referred either atlas structural/functional database healthy brains (dis)connectivity (Carson survivor, programme tailored 'recovery connectome' (Latifi Carmichael. papers collected illustrate concerning level, antecedent efficacious Such interruptions brain. lingua franca demanded match 2024) constituted processes, Please note: publisher responsible content functionality supplied authors. Any queries missing content) directed corresponding author article. No competing interests declared. Sole author. funding.

Language: Английский

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Post-stroke dysphagia: Neurological regulation and recovery strategies

BioScience Trends, Journal Year: 2025, Volume and Issue: 19(1), P. 31 - 52

Published: Feb. 21, 2025

Swallowing is a complex process requiring precise coordination of numerous muscles in the head and neck to smoothly guide ingested material from mouth stomach. Animal human studies have revealed network neurons brainstem, cortex, cerebellum that coordinate normal swallowing. The interactions between these regions ensure smooth efficient However, current understanding neurophysiological mechanisms involved post-stroke dysphagia (PSD) incomplete, complete functional connectivity for swallowing recovery remains understudied requires further exploration. In this review, we discussed neuroanatomy pathogenesis PSD summarized factors affecting recovery. We also described plasticity neural networks PSD, including enhancing activation pathways, cortical reorganization, regulation extracellular matrix dynamics its components, modulation neurotransmitter delivery, identification potential therapeutic targets PSD. Finally, strategies based on compensation motor learning. This review aimed provide reference clinicians researchers promote optimization treatments explore future research directions.

Language: Английский

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Feasibility of Cerebellar Stimulation for the Treatment of Post-Stroke Dysphagia

The Cerebellum, Journal Year: 2025, Volume and Issue: 24(3)

Published: March 26, 2025

Language: Английский

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Clinical predictors of outcome after pharyngeal electrical stimulation (PES) in non-stroke related neurogenic dysphagia after mechanical ventilation and tracheotomy: results from subgroup analysis of PHADER study

Neurological Research and Practice, Journal Year: 2025, Volume and Issue: 7(1)

Published: April 6, 2025

Abstract Background Pharyngeal electrical stimulation (PES) is a neurostimulation intervention that can improve swallowing and facilitate decannulation in tracheotomised stroke patients with dysphagia. The PHAryngeal for treatment of neurogenic Dysphagia European Registry (PHADER) study found PES reduce dysphagia severity (non-stroke) who required mechanical ventilation tracheotomy. However, the predictive factors success among these remain unclear. Methods We conducted subgroup analysis using data from PHADER, focus on non-stroke participants had Multiple linear regression was performed to predict success, as measured improvement rating scale (DSRS) total score, accounting age, sex, time diagnosis PES, perceptual threshold intensity at first session. Results Fifty-seven (mean[standard deviation] age: 63.6[15.5] years; male: 70.2%) were included analysis. These comprised traumatic brain injury (22[38.6%]), critical illness polyneuropathy (15[26.4%]), other neurological conditions caused (20[35.0%]). Regression analyses identified lower session ( p = 0.027) early 0.004) significant predictors associated Day 9 3 months post respectively. Conclusions two successful requiring tracheotomy: intervention. provide guidance optimizing clinical decision-making managing care settings.

Language: Английский

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Poststroke Lingual Function and Swallowing Physiology

Journal of Speech Language and Hearing Research, Journal Year: 2025, Volume and Issue: 68(05), P. 2318 - 2338

Published: April 24, 2025

Poststroke dysphagia is characterized by deficits in lingual function. However, correlations between function and oral pharyngeal swallowing impairments have not been well defined. The aim of this preliminary study was to explore if tongue pressure generative capacity patients after ischemic stroke associated with oropharyngeal impairments. A cross-sectional convenience sample underwent a videofluoroscopic (VFSS) completed measures (Saliva Swallow Pressure, maximum isometric [MIP], Maximum Isometric Endurance [ISO-M], Isotonic [ISO-T]) using the Tongueometer Iowa Oral Performance Instrument (IOPI) manometry instruments. VFSS for each participant were consensus scored two Modified Barium Impairment Profile (MBSImP)-certified raters. MBSImP Total Pharyngeal scores calculated, Swallow-by-Swallow summarized calculating percentage worst possible score across all bolus presentations that score. Lingual measurements (swallow pressures, MIP, ISO-M, ISO-T) averaged participants, Spearman's correlation coefficients used assess relationships these scores. final consisted 39 participants post-ischemic (ranging from 3 months 27 months). Average MIP 49.6 kPA (11.25), Saliva average 19.0 kPa ISO-M 11.1 s (12.65), ISO-T repetitions 30 (22.8). There significant, moderate (r = -.41, p .0082); Component 1, Lip Closure -.46, .0026); 2, Tongue Control -.48, .0016). All other nonsignificant. endurance correlated physiologic swallow Inclusion testing poststroke populations may add value clinical assessment. Future studies should examine predictive functional predicting dysfunction.

Language: Английский

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Establishment and validation of early prediction model for post-stroke dysphagia

Aging Clinical and Experimental Research, Journal Year: 2025, Volume and Issue: 37(1)

Published: May 11, 2025

Stroke is a leading cause of death and disability worldwide, with dysphagia being common complication that worsens patient outcomes. Data from 200 stroke patients (development cohort) 50 (validation were analyzed to develop nomogram for predicting post-stroke (PSD). Risk factors identified through univariate analysis, Least Absolute Shrinkage Selection Operator (LASSO) regression, multivariate logistic regression. Univariate analysis revealed substantial differences in age, body mass index (BMI), diabetes, atrial fibrillation, National Institute Health Scale (NIHSS) score, Activities Daily Living (ADL) lesion site, type, several laboratory indicators across the groups. Further individual NIHSS items showed significant consciousness level, best gaze, facial palsy, motor arm, leg, dysarthria, etc. LASSO regression three predictors: ADL dysarthria. Multivariable score [0.96 (0.94-0.97)], leg [5.70 (2.14-15.22)], dysarthria [5.26 (2.00-13.82)] independent risk PSD. The prediction model's AUC was 0.915 (0.874-0.955), sensitivity 0.920 (0.867-0.973), specificity 0.800 (0.722-0.878), positive predictive value (PPV) 0.821 (0.750-0.892), negative (NPV) 0.909 (0.849-0.969), F1 0.859. External validation yielded an 0.995 (0.984-1.000). are predictors model based on these shows high accuracy, sensitivity, balance, consistency, clinical applicability. This can support decision-making ultra-early rehabilitation care, ultimately improving prognosis.

Language: Английский

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The impact of physical therapy on dysphagia in neurological diseases: a review

Frontiers in Human Neuroscience, Journal Year: 2024, Volume and Issue: 18

Published: June 6, 2024

A neurogenic dysphagia is caused by problems with the central and peripheral nervous systems, particularly prevalent in conditions such as Parkinson’s disease stroke. It significantly impacts quality of life for affected individuals causes additional burdens, malnutrition, aspiration pneumonia, asphyxia, or even death from choking due to improper eating. Physical therapy offers a non-invasive treatment high efficacy low cost. Evidence supporting use physical increasing, including techniques neuromuscular electrical stimulation, sensory transcranial direct current repetitive magnetic stimulation. While initial studies have shown promising results, effectiveness specific regimens still requires further validation. At present, there lack scientific evidence guide patient selection, develop appropriate regimens, accurately evaluate outcomes. Therefore, primary objectives this review are results existing research, summarize application management, we also discussed mechanisms treatments dysphagia.

Language: Английский

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Prevalence and influencing factors of malnutrition in stroke patients with bulbar paralysis: a cross-sectional study in China

Frontiers in Nutrition, Journal Year: 2024, Volume and Issue: 11

Published: April 17, 2024

Although malnutrition has been shown to influence the clinical outcomes of Stroke Patients with Bulbar Paralysis (SPBP), prevalence and influencing factors have yet be uncovered.

Language: Английский

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Cranial Nerve Deficits Predict Pharyngeal Phase Swallowing Impairment in Patients with Neurogenic Dysphagia: A Cross-Sectional Study

Dysphagia, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 9, 2024

Language: Английский

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Effect of transcranial direct current stimulation on swallowing improvement and cortical excitability in hemispheric stroke patients: a randomized, sham-controlled trial

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 20, 2024

Transcranial direct current stimulation (tDCS) has been extensively utilized in the treatment of post-stroke dysphagia; however, effect different tDCS protocols remains uncertain. This study aims to investigate on dysphagia after hemispheric stroke and compare among three protocols. A total 90 patients were randomized into groups: bilateral, contralesional, ipsilesional tDCS. Each group received anodal over orofacial sensorimotor cortex (S1M1) hemispheres, respectively, administered for 20 sessions overall, combined with exercise-based swallowing therapy. After tDCS, both assessment scale swallow severity showed significant improvement all groups (all p <0.01). In comparisons groups, bilateral demonstrated significantly greater than contralesional group, terms <0.001) <0.05). The analysis ApEn increased cortical excitability stimulated non-stimulated areas hemispheres unilateral Moreover, larger activated compared those Trial registration: ChiCTR-TRC-14004955(16/07/2014).

Language: Английский

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