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Cortex; a Journal Devoted To the Study... Feb 2024Stimulation-based language mapping approaches that are used pre- and intraoperatively employ predominantly overt language tasks requiring sufficient language production...
OBJECTIVE
Stimulation-based language mapping approaches that are used pre- and intraoperatively employ predominantly overt language tasks requiring sufficient language production abilities. Yet, these production-based setups are often not feasible in brain tumor patients with severe expressive aphasia. This pilot study evaluated the feasibility and reliability of a newly developed language comprehension task with preoperative navigated transcranial magnetic stimulation (nTMS).
METHODS
Fifteen healthy subjects and six brain tumor patients with severe expressive aphasia unable to perform classic overt naming tasks underwent preoperative nTMS language mapping based on an auditory single-word Comprehension TAsk for Perioperative mapping (CompreTAP). Comprehension was probed by button-press responses to auditory stimuli, hence not requiring overt language responses. Positive comprehension areas were identified when stimulation elicited an incorrect or delayed button press. Error categories, case-wise cortical error rate distribution and inter-rater reliability between two experienced specialists were examined.
RESULTS
Overall, the new setup showed to be feasible. Comprehension-disruptions induced by nTMS manifested in no responses, delayed or hesitant responses, searching behavior or selection of wrong target items across all patients and controls and could be performed even in patients with severe expressive aphasia. The analysis agreement between both specialists was substantial for classifying comprehension-positive and -negative sites. Extensive left-hemispheric individual cortical comprehension sites were identified for all patients. Apart from one case presenting with transient worsening of aphasic symptoms, pre-existing language deficits did not aggravate if results were used for subsequent surgical planning.
CONCLUSION
Employing this new comprehension-based nTMS setup allowed to identify language relevant cortical sites in all healthy subjects and severely aphasic patients who were thus far precluded from classic production-based mapping. This pilot study, moreover, provides first indications that the CompreTAP mapping results may support the preservation of residual language function if used for subsequent surgical planning.
Topics: Humans; Transcranial Magnetic Stimulation; Comprehension; Aphasia, Broca; Reproducibility of Results; Feasibility Studies; Pilot Projects; Brain Mapping; Brain Neoplasms
PubMed: 38086145
DOI: 10.1016/j.cortex.2023.09.023 -
Annual International Conference of the... Jul 2023Damage to the inferior frontal gyrus (Broca's area) can cause agrammatic aphasia wherein patients, although able to comprehend, lack the ability to form complete...
Damage to the inferior frontal gyrus (Broca's area) can cause agrammatic aphasia wherein patients, although able to comprehend, lack the ability to form complete sentences. This inability leads to communication gaps which cause difficulties in their daily lives. The usage of assistive devices can help in mitigating these issues and enable the patients to communicate effectively. However, due to lack of large scale studies of linguistic deficits in aphasia, research on such assistive technology is relatively limited. In this work, we present two contributions that aim to re-initiate research and development in this field. Firstly, we propose a model that uses linguistic features from small scale studies on aphasia patients and generates large scale datasets of synthetic aphasic utterances from grammatically correct datasets. We show that the mean length of utterance, the noun/verb ratio, and the simple/complex sentence ratio of our synthetic datasets correspond to the reported features of aphasic speech. Further, we demonstrate how the synthetic datasets may be utilized to develop assistive devices for aphasia patients. The pre-trained T5 transformer is fine-tuned using the generated dataset to suggest 5 corrected sentences given an aphasic utterance as input. We evaluate the efficacy of the T5 model using the BLEU and cosine semantic similarity scores. Affirming results with BLEU score of 0.827/1.00 and semantic similarity of 0.904/1.00 were obtained. These results provide a strong foundation for the concept that a synthetic dataset based on small scale studies on aphasia can be used to develop effective assistive technology.Clinical relevance- We demonstrate the utilization of Natural Language Processing (NLP) for developing assistive technology for Aphasia patients. While disorders like Broca's aphasia offer a small sample size of patients and data, synthetic linguistic models like ours offer extensive scope for developing assistive technology and rehabilitation monitoring.
Topics: Humans; Natural Language Processing; Aphasia, Broca; Linguistics; Language; Semantics
PubMed: 38082780
DOI: 10.1109/EMBC40787.2023.10340559 -
Rinsho Shinkeigaku = Clinical Neurology Jan 2024The first case was a 75-year-old woman with intermittent sensory impairment of the left hand. FLAIR of the head MRI revealed hyperintensity along the pia mater in the...
The first case was a 75-year-old woman with intermittent sensory impairment of the left hand. FLAIR of the head MRI revealed hyperintensity along the pia mater in the right parieto-temporal lobe with few microbleeds. Our second case was a 78-year-old man who presented with motor aphasia. His MRI showed swollen cortex on FLAIR and cortical hemosiderosis on T* weighted imaging of the right cerebral hemisphere. Pathological findings indicated the first case as cerebral amyloid angiopathy (CAA)-related inflammation and the second case as CAA. Additionally, after brain biopsy, widespread white matter lesions were detected in the area surrounding the biopsy site. However, both patients showed improvement without immunotherapy. Therefore, it is important to consider whether immunotherapy is required when white matter lesions appear in the area surrounding the biopsy site.
Topics: Male; Female; Humans; Aged; White Matter; Cerebral Amyloid Angiopathy; Magnetic Resonance Imaging; Immunotherapy; Biopsy; Cerebral Hemorrhage
PubMed: 38072444
DOI: 10.5692/clinicalneurol.cn-001887 -
Journal of Neurology, Neurosurgery, and... Feb 2024Language impairment (aphasia) is a common neurological deficit after strokes. For individuals with chronic aphasia (beyond 6 months after the stroke), language... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Language impairment (aphasia) is a common neurological deficit after strokes. For individuals with chronic aphasia (beyond 6 months after the stroke), language improvements with speech therapy (ST) are often limited. Transcranial direct current stimulation (tDCS) is a promising approach to complement language recovery but interindividual variability in treatment response is common after tDCS, suggesting a possible relationship between tDCS and type of linguistic impairment (aphasia type).
METHODS
This current study is a subgroup analysis of a randomised controlled phase II futility design clinical trial on tDCS in chronic post-stroke aphasia. All participants received ST coupled with tDCS (n=31) vs sham tDCS (n=39). Confrontation naming was tested at baseline, and 1, 4, and 24 weeks post-treatment.
RESULTS
Broca's aphasia was associated with maximal adjunctive benefit of tDCS, with an average improvement of 10 additional named items with tDCS+ST compared with ST alone at 4 weeks post-treatment. In comparison, tDCS was not associated with significant benefits for other aphasia types (1)=4.23, =0.04. Among participants with Broca's aphasia, preservation of the perilesional posterior inferior temporal cortex was associated with higher treatment benefit (=0.35, =0.03).
CONCLUSIONS
These results indicate that adjuvant tDCS can enhance ST to treat naming in Broca's aphasia, and this may guide intervention approaches in future studies.
Topics: Humans; Transcranial Direct Current Stimulation; Aphasia; Stroke; Language; Speech Therapy
PubMed: 38071545
DOI: 10.1136/jnnp-2023-331541 -
Cureus Nov 2023Hemiballismus is defined as irregular, involuntary, large-amplitude flinging movements by the limbs, confined to one side of the body. Hemichorea refers to a state of...
Hemiballismus is defined as irregular, involuntary, large-amplitude flinging movements by the limbs, confined to one side of the body. Hemichorea refers to a state of excessive and irregularly timed, non-repetitive and randomly distributed, spontaneous, involuntary, and abrupt movements. It is widely believed that hemiballismus and chorea are suggestive of a lesion to the basal ganglia and subthalamic nucleus (STN). However, there are other etiologies that may influence the clinical presentation. Patients may present with certain common clinical features corresponding to the affected area of the brain. For example, infarctions of the motor cortex present with hemiplegia or paralysis of one side of the body. Similarly, infarctions involving the language areas of the brain present with aphasia and are detrimental to speech production or comprehension and the ability to read and write. Typically, acute-onset hemichorea is suggestive of a lesion in the STN. Herein, we present a rare case of acute hemiballismus and hemichorea following infarction of the left caudate nucleus, as determined by magnetic resonance imaging (MRI) and computerized tomography (CT) imaging modalities.
PubMed: 38050508
DOI: 10.7759/cureus.48209 -
Frontiers in Neurology 2023Functional restoration of hemiplegic upper limbs is a difficult area in the field of neurological rehabilitation. Electrical stimulation is one of the treatments that...
BACKGROUND
Functional restoration of hemiplegic upper limbs is a difficult area in the field of neurological rehabilitation. Electrical stimulation is one of the treatments that has shown promising advancements and functional improvements. Most of the electrical stimulations used in clinical practice are surface stimulations. In this case, we aimed to investigate the feasibility of a minimally invasive, ultrasound-guided median nerve electrical stimulation (UG-MNES) in improving the upper limb motor function and activity of a patient with right-sided hemiparesis.
CASE PRESENTATION
A 65-year-old male recovering from a left massive intracerebral hemorrhage after open debridement hematoma removal had impaired right limb movement, right hemianesthesia, motor aphasia, dysphagia, and complete dependence on his daily living ability. After receiving 3 months of conventional rehabilitation therapy, his cognitive, speech, and swallowing significantly improved but the Brunnstrom Motor Staging (BMS) of his right upper limb and hand was at stage I-I. UG-MNES was applied on the right upper limb for four sessions, once per week, together with conventional rehabilitation. Immediate improvement in the upper limb function was observed after the first treatment. To determine the effect of UG-MNES on long-term functional recovery, assessments were conducted a week after the second and fourth intervention sessions, and motor function recovery was observed after 4-week of rehabilitation. After completing the full rehabilitation course, his BMS was at stage V-IV, the completion time of Jebsen Hand Function Test (JHFT) was shortened, and the scores of Fugl-Meyer Assessment for upper extremity (FMA-UE) and Modified Barthel Index (MBI) were increased. Overall, the motor function of the hemiplegic upper limb had significantly improved, and the right hand was the utility hand. Electromyography (EMG) and nerve conduction velocity (NCV) tests were normal before and after treatment.
CONCLUSION
The minimally invasive, UG-MNES could be a new alternative treatment in stroke rehabilitation for functional recovery of the upper limbs.
PubMed: 38046582
DOI: 10.3389/fneur.2023.1244192 -
Current Neurology and Neuroscience... Dec 2023Stroke remains a leading disabling condition, and many survivors have permanent disability despite acute stroke treatment and subsequent standard-of-care rehabilitation... (Meta-Analysis)
Meta-Analysis Review
PURPOSE OF REVIEW
Stroke remains a leading disabling condition, and many survivors have permanent disability despite acute stroke treatment and subsequent standard-of-care rehabilitation therapies. Adjunctive neuromodulation is an emerging frontier in the field of stroke recovery. In this narrative review, we aim to highlight and summarize various neuromodulation techniques currently being investigated to enhance recovery and reduce impairment in patients with stroke.
RECENT FINDINGS
For motor recovery, repetitive transcranial magnetic simulation (rTMS) and direct current stimulation (tDCS) have shown promising results in many smaller-scale trials. Still, their efficacy has yet to be proven in large-scale pivotal trials. A promising large-scale study investigating higher dose tDCS combined with constraint movement therapy to enhance motor recovery is currently underway. MRI-guided tDCS studies in subacute and chronic post-stroke aphasia showed promising benefits for picture-naming recovery. rTMS, particularly inhibitory stimulation over the contralesional homolog, could represent a pathway forward in post-stroke motor recovery in the setting of a well-designed and adequately powered clinical trial. Recently evidenced-based guideline actually supported Level A (definite efficacy) for the use of low-frequency rTMS of the primary motor cortex for hand motor recovery in the post-acute stage of stroke based on the meta-analysis result. Adjunctive vagal nerve stimulation has recently received FDA approval to enhance upper limb motor recovery in chronic ischemic stroke with moderate impairment, and progress has been made to implement it in real-world practice. Despite a few small and large-scale studies in epidural stimulation (EDS), further research on the utilization of EDS in post-stroke recovery is needed. Deep brain stimulation or stent-based neuromodulation has yet to be further tested regarding safety and efficacy. Adjunctive neuromodulation to rehabilitation therapy is a promising avenue for promoting post-stroke recovery and decreasing the overall burden of disability. The pipeline for neuromodulation technology remains strong as they span from the preclinical stage to the post-market stage. We are optimistic to see that more neuromodulation tools will be available to stroke survivors in the not-to-distant future.
Topics: Humans; Transcranial Magnetic Stimulation; Stroke Rehabilitation; Stroke; Transcranial Direct Current Stimulation; Upper Extremity; Recovery of Function
PubMed: 38015351
DOI: 10.1007/s11910-023-01319-6 -
The Surgeon : Journal of the Royal... Feb 2024Studies from the UK reporting on awake craniotomy (AC) include a heterogenous group of patients which limit the evaluation of the true impact of AC in high-grade glioma...
BACKGROUND
Studies from the UK reporting on awake craniotomy (AC) include a heterogenous group of patients which limit the evaluation of the true impact of AC in high-grade glioma (HGG) patients. This study aims to report solely the experience and outcomes of AC for HGG surgery from our centre.
METHODS
A prospective review of all patients who underwent AC for HGG from 2013 to 2019 were performed. Data on patient characteristics including but not limited to demographics, pre- and post-operative Karnofsky performance status (KPS), tumour location and volume, type of surgery, extent of resection (EOR), tumour histopathology, intra- and post-operative complications, morbidity, mortality, disease recurrence, progression-free survival (PFS) and overall survival (OS) from the time of surgery were collected.
RESULTS
Fifteen patients (6 males; 9 females; 17 surgeries) underwent AC for HGG (median age = 55 years). Two patients underwent repeat surgeries due to disease recurrence. Median pre- and post-operative KPS score was 90 (range:80-100) and 90 (range:60-100), respectively. The EOR ranges from 60 to 100 % with a minimum of 80 % achieved in 81.3 % cases. Post-operative complications include focal seizures (17.6 %), transient aphasia/dysphasia (17.6 %), permanent motor deficit (11.8 %), transient motor deficit (5.9 %) and transient sensory disturbance (5.9 %). There were no surgery-related mortality or post-operative infection. The median PFS and OS were 13 (95%CI 5-78) and 30 (95%CI 21-78) months, respectively.
CONCLUSION
This is the first study in the UK to solely report outcomes of AC for HGG surgery. Our data demonstrates that AC for HGG in eloquent region is safe, feasible and provides comparable outcomes to those reported in the literature.
Topics: Male; Female; Humans; Middle Aged; Brain Neoplasms; Prospective Studies; Wakefulness; Neoplasm Recurrence, Local; Glioma; Craniotomy; Postoperative Complications; United Kingdom; Retrospective Studies
PubMed: 38008681
DOI: 10.1016/j.surge.2023.11.002 -
Brain Sciences Nov 2023Based on the seminal publications of Paul Broca and Carl Wernicke who established that aphasic syndromes (disorders of the verbal-linguistic aspects of communication)... (Review)
Review
Based on the seminal publications of Paul Broca and Carl Wernicke who established that aphasic syndromes (disorders of the verbal-linguistic aspects of communication) were predominantly the result of focal left-hemisphere lesions, "language" is traditionally viewed as a lateralized function of the left hemisphere. This, in turn, has diminished and delayed the acceptance that the right hemisphere also has a vital role in language, specifically in modulating affective prosody, which is essential for communication competency and psychosocial well-being. Focal lesions of the right hemisphere may result in disorders of affective prosody (aprosodic syndromes) that are functionally and anatomically analogous to the aphasic syndromes that occur following focal left-hemisphere lesions. This paper will review the deductive research published over the last four decades that has elucidated the neurology of affective prosody which, in turn, has led to a more complete and nuanced understanding of the neurology of language, depression, emotions and memory. In addition, the paper will also present the serendipitous clinical observations (inductive research) and fortuitous inter-disciplinary collaborations that were crucial in guiding and developing the deductive research processes that culminated in the concept that primary emotions and related display behaviors are a lateralized function of the right hemisphere and social emotions, and related display behaviors are a lateralized function of the left hemisphere.
PubMed: 38002532
DOI: 10.3390/brainsci13111572 -
Experimental Brain Research Jan 2024The present study examined opposing and following vocal responses to altered auditory feedback (AAF) to determine how damage to left-hemisphere brain networks impairs...
Impairment of the internal forward model and feedback mechanisms for vocal sensorimotor control in post-stroke aphasia: evidence from directional responses to altered auditory feedback.
The present study examined opposing and following vocal responses to altered auditory feedback (AAF) to determine how damage to left-hemisphere brain networks impairs the internal forward model and feedback mechanisms in post-stroke aphasia. Forty-nine subjects with aphasia and sixty age-matched controls performed speech vowel production tasks while their auditory feedback was altered using randomized ± 100 cents upward and downward pitch-shift stimuli. Data analysis revealed that when vocal responses were averaged across all trials (i.e., opposing and following), the overall magnitude of vocal compensation was significantly reduced in the aphasia group compared with controls. In addition, when vocal responses were analyzed separately for opposing and following trials, subjects in the aphasia group showed a significantly lower percentage of opposing and higher percentage of following vocal response trials compared with controls, particularly for the upward pitch-shift stimuli. However, there was no significant difference in the magnitude of opposing and following vocal responses between the two groups. These findings further support previous evidence on the impairment of vocal sensorimotor control in aphasia and provide new insights into the distinctive impact of left-hemisphere stroke on the internal forward model and feedback mechanisms. In this context, we propose that the lower percentage of opposing responses in aphasia may be accounted for by deficits in feedback-dependent mechanisms of audio-vocal integration and motor control. In addition, the higher percentage of following responses may reflect aberrantly increased reliance of the speech system on the internal forward model for generating sensory predictions during vocal error detection and motor control.
Topics: Humans; Feedback; Pitch Perception; Voice; Speech; Feedback, Sensory; Aphasia
PubMed: 37999725
DOI: 10.1007/s00221-023-06743-1