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Neurobiology of Language (Cambridge,... 2024Hearing one's own speech allows for acoustic self-monitoring in real time. Left-hemisphere motor planning regions are thought to give rise to efferent predictions that...
Hearing one's own speech allows for acoustic self-monitoring in real time. Left-hemisphere motor planning regions are thought to give rise to efferent predictions that can be compared to true feedback in sensory cortices, resulting in neural suppression commensurate with the degree of overlap between predicted and actual sensations. Sensory prediction errors thus serve as a possible mechanism of detection of deviant speech sounds, which can then feed back into corrective action, allowing for online control of speech acoustics. The goal of this study was to assess the integrity of this detection-correction circuit in persons with aphasia (PWA) whose left-hemisphere lesions may limit their ability to control variability in speech output. We recorded magnetoencephalography (MEG) while 15 PWA and age-matched controls spoke monosyllabic words and listened to playback of their utterances. From this, we measured speaking-induced suppression of the M100 neural response and related it to lesion profiles and speech behavior. Both speaking-induced suppression and cortical sensitivity to deviance were preserved at the group level in PWA. PWA with more spared tissue in pars opercularis had greater left-hemisphere neural suppression and greater behavioral correction of acoustically deviant pronunciations, whereas sparing of superior temporal gyrus was not related to neural suppression or acoustic behavior. In turn, PWA who made greater corrections had fewer overt speech errors in the MEG task. Thus, the motor planning regions that generate the efferent prediction are integral to performing corrections when that prediction is violated.
PubMed: 38911464
DOI: 10.1162/nol_a_00139 -
Frontiers in Neuroscience 2024Anodal transcranial Direct Current Stimulation (tDCS) is a non-invasive, low-cost and environment-friendly brain neuromodulation technique that increases cortical...
INTRODUCTION
Anodal transcranial Direct Current Stimulation (tDCS) is a non-invasive, low-cost and environment-friendly brain neuromodulation technique that increases cortical excitability. In post-stroke aphasia, the role of the right hemisphere in language recovery remains debated. In this preliminary study, we aimed to investigate the efficacy of excitatory tDCS on the right hemisphere in chronic aphasic patients.
METHODS
We applied anodal tDCS to the right homologous region of Broca's area in four chronic aphasic patients while performing a one-month naming rehabilitation treatment. Longitudinal data on language assessment and naming performance were collected. Resting-state fMRI images were acquired before and after treatment to measure changes in functional connectivity.
RESULTS
Results showed enhanced positive functional connectivity of the right Broca homologous with the left middle frontal and middle temporal gyri. Every patient showed improvements in language functions, but no major changes in naming performance.
CONCLUSION
These preliminary findings suggest that tDCS applied over the unaffected hemisphere may result in longitudinal inter-hemispheric functional neuroplastic changes that could specifically improve language recovery and could potentially be included in therapeutic neurorehabilitative plans.
PubMed: 38406588
DOI: 10.3389/fnins.2024.1346095 -
Cureus May 2024Central neurocytoma (CN) is a rare, low-grade, neuronal tumor frequently encountered in young adults. Complete surgical resection is the treatment of choice; however, it...
Central neurocytoma (CN) is a rare, low-grade, neuronal tumor frequently encountered in young adults. Complete surgical resection is the treatment of choice; however, it is associated with grave postoperative complications in a quarter of patients, including neurological (motor weakness, memory deficit, aphasia, and seizure) as well as regional (hydrocephalus, hematoma, infection, and subcutaneous hydrops) complications. Herein, we present a case of a 35-year-old female who presented with decreased vision for the last 7-8 days and headache over the last 1-1.5 years. An ophthalmologic examination suggested papilledema. Magnetic resonance imaging (MRI) of the brain illustrated a well-circumscribed, large, lobulated, altered signal intensity midline intraventricular lesion (72 × 68 mm) attached to the septum pellucidum near the foramen of Monro (FoM) most likely to be CN. The patient underwent complete surgical resection but required re-exploration the next day for hematoma removal due to intraventricular hemorrhage. Over the next 40 days, the patient developed hydrocephalus with transtentorial herniation and succumbed. Histopathological examination (HPE) was suggestive of CN and immunohistochemistry (IHC) was strongly positive for synaptophysin, thus confirming the diagnosis of CN.
PubMed: 38915980
DOI: 10.7759/cureus.60969 -
Journal of Traditional Chinese Medicine... Feb 2024Stroke is the main cause of disability in the middle and old age. Hemiplegia, especially lower limb paralysis, often leads to the loss of self-care ability and a series...
Stroke is the main cause of disability in the middle and old age. Hemiplegia, especially lower limb paralysis, often leads to the loss of self-care ability and a series of secondary injuries. The main method to improve hemiplegic limb movement is exercise therapy, but there are still many patients with disabilities after rehabilitation treatment. As one of the non-pharmacological therapies for stroke, acupuncture has been recognized to improve motor function in patients. Here, we propose a new method, anterior sciatic nerve acupuncture, which can stimulate both the femoral nerve and the sciatic nerve. We designed this study to determine the effect of this method on lower limb motor function. Sixty participants recruited with hemiplegia after cerebral infarction will be randomly assigned to the test group or control group in a 1:1 ratio. The control group will receive Xingnao Kaiqiao acupuncture, and the test group will receive anterior sciatic nerve acupuncture on this basis. All participants will get acupuncture treatment once a day, 6 times a week for 2 weeks. The primary outcome is Fugl-Meyer Assessment of Lower Extremity and the secondary outcomes are Modified Ashworth Scale and Modified Barthel Index. Data will be collected before treatment, 1 week after treatment, and 2 weeks after treatment, and then statistical analysis will be performed. This study can preliminarily verify the effect of anterior sciatic nerve acupuncture on improving lower limb motor function in patients with cerebral infarction, which may provide an alternative approach for clinical treatment of hemiplegia.
Topics: Humans; Hemiplegia; Treatment Outcome; Stroke; Cerebral Infarction; Acupuncture Therapy; Randomized Controlled Trials as Topic
PubMed: 38213256
DOI: 10.19852/j.cnki.jtcm.2024.01.001 -
Cureus Mar 2024Posterior reversible encephalopathy syndrome (PRES) is an uncommon yet severe neurological disorder characterized by a combination of clinical and radiological features....
Posterior reversible encephalopathy syndrome (PRES) is an uncommon yet severe neurological disorder characterized by a combination of clinical and radiological features. Common clinical presentations of PRES include headaches, seizures, altered mental status ranging from lethargy to coma, visual disturbances, and behavior changes. This case report outlines the occurrence of hemorrhagic PRES in an 11-year-old girl with B-cell acute lymphoblastic leukemia (ALL) relapse. Hospitalized for ALL relapse, the patient underwent reinduction chemotherapy. On the ninth day of admission, she had a generalized tonic-clonic seizure with a blood pressure peak of 170/120 mmHg. Magnetic resonance imaging (MRI) and a seizure episode suggested PRES. Initially, after the first tonic-clonic seizure, the neurological examination was normal, but after the second seizure, the meningeal symptoms were negative, and gaze palsy and right-sided homonymous hemianopsia were observed; muscle strength was symmetrically reduced in the upper and lower extremities and reflexes were symmetrical and diminished. A bilateral Babinski reflex was observed at the time of examination; the patient had mild motor aphasia, and she opened her eyes only in response to tactile stimulation. A follow-up MRI four days after the second seizure episode showed extensive PRES damage with hemorrhagic changes. Over two weeks, the patient's neurological status and blood pressure gradually improved, with persistent changes in the visual field. Subsequent MRI revealed a significant reduction in PRES lesions, but residual hemorrhage measuring 6x4 cm remained evident.
PubMed: 38681433
DOI: 10.7759/cureus.57158 -
Cureus Mar 2024Melodic intonation therapy (MIT) is one of the rehabilitation methods for patients with non-fluent or dysfluent aphasia, mainly caused by stroke or brain injury....
Melodic intonation therapy (MIT) is one of the rehabilitation methods for patients with non-fluent or dysfluent aphasia, mainly caused by stroke or brain injury. Although MIT is conducted in various languages, reports on the Japanese version of MIT (MIT-J) are limited. In this report, we describe a case about the efficacy of MIT-J in the subacute phase after stroke on subcortical aphasia. Our case was a 60-year-old right-handed woman who suffered from left putaminal hemorrhage. She was treated with acute therapy, including medications and rehabilitation, but non-fluent aphasia was preserved. Regardless of general speech therapies, her aphasia was not improved. In the subacute phase, we started MIT-J (protocol: 20 minutes per day, five days per week for two weeks). The effect of MIT-J was remarkable and in particular, speech intelligibility was improved. It is required to accumulate more cases to reveal the effect of MIT-J.
PubMed: 38576684
DOI: 10.7759/cureus.55590 -
F1000Research 2023Alien hand syndrome (AHS) is a rare neurological phenomenon first described by Van Vleuten over a century ago. The most widely recognized variants in literature are...
Alien hand syndrome (AHS) is a rare neurological phenomenon first described by Van Vleuten over a century ago. The most widely recognized variants in literature are frontal, callosal, and posterior AHS. AHS due to the corpus callosum lesion can occur alone or as part of callosal disconnection syndrome (CDS). This report presents a unique CDS case manifesting clinical features from all three AHS variants, resulting from an extensive corpus callosum infarct. Our patient exhibited various clinical features from the three AHS variants, which include grasping, groping, and difficulty releasing objects from the hand (anterior); intermanual conflict (callosal); arm levitation, mild hemiparesis, and hemisensory loss (posterior). Additionally, the extensive disruption of the corpus callosal fibers produced neurological manifestations of CDS, such as cognitive impairment, ideomotor and constructional apraxia, behavioral disorder, and transcortical motor aphasia. We employed a range of rehabilitation interventions, such as mirror box therapy, limb restraint strategy, verbal cue training, cognitive behavioral therapy, bimanual hand training, speech and language therapy, and pharmacological treatment with clonazepam. The patient showed almost complete resolution of CDS and AHS features by nine months post-stroke Our case report highlights distinctive clinical variations of AHS and the challenging correlation between clinical manifestations and neuroanatomical substrates. Future studies are necessary to explore the intricate neural connections and the precise function of the corpus callosum. This can be achieved by combining comprehensive neuropsychological testing with diffusion tensor tractography studies. It is also essential to develop a validated tool to standardize AHS assessment. Finally, the scarcity of evidence in rehabilitation interventions necessitates further studies to address the wide knowledge gap in AHS and CDS management.
PubMed: 38716229
DOI: 10.12688/f1000research.133838.1 -
Geriatrics (Basel, Switzerland) Mar 2024Intravenous thrombolysis and mechanical thrombectomy are the first-line reperfusion therapies for acute ischemic stroke. Here, we describe the utility of diffusion...
Diffusion MRI Fiber Tractography and Benzodiazepine SPECT Imaging for Assessing Neural Damage to the Language Centers in an Elderly Patient after Successful Reperfusion Therapy.
BACKGROUND
Intravenous thrombolysis and mechanical thrombectomy are the first-line reperfusion therapies for acute ischemic stroke. Here, we describe the utility of diffusion magnetic resonance imaging (MRI) fiber tractography and I-iomazenil benzodiazepine receptor single-photon emission computed tomography to estimate the prognosis of post-stroke aphasia after successful reperfusion therapy.
CASE REPORT
An 81-year-old man was admitted to the hospital approximately 3.5 h after the onset of symptoms, including decreased consciousness, right hemiparesis, and aphasia. An MRI revealed acute cerebral infarction due to M1 segment occlusion. Intravenous alteplase thrombolysis followed by endovascular thrombectomy resulted in recanalization of the left middle cerebral artery territory. A subsequent MRI showed no new ischemic or hemorrhagic lesions. Although the patient's motor hemiparesis gradually recovered, motor aphasia persisted. Diffusion MRI fiber tractography performed 2 weeks after admission revealed partial injury to the left arcuate fasciculus, indicated by lower fractional anisotropy values than on the contralateral side. A decreased benzodiazepine receptor density was also detected in the left perisylvian and temporoparietal cortices. The patient showed no clear signs of further improvement in the chronic stage post-stroke and was discharged to a nursing home after 3 months.
CONCLUSIONS
The application of functional neuroimaging techniques to assess neuronal damage to the primary brain regions 2 weeks after reperfusion therapy for large-vessel occlusion may allow for an accurate prognosis of post-stroke aphasia. This may have a direct clinical implication for navigating subacute-to-chronic phases of rehabilitative care.
PubMed: 38525747
DOI: 10.3390/geriatrics9020030 -
International Journal of Molecular... Mar 2024The L1 cell adhesion molecule (L1) has demonstrated a range of beneficial effects in animal models of spinal cord injury, neurodegenerative disease, and ischemia;...
The L1 cell adhesion molecule (L1) has demonstrated a range of beneficial effects in animal models of spinal cord injury, neurodegenerative disease, and ischemia; however, the role of L1 in TBI has not been fully examined. Mutations in the gene affecting the extracellular domain of this type 1 transmembrane glycoprotein have been identified in patients with L1 syndrome. These patients suffer from hydrocephalus, MASA (mental retardation, adducted thumbs, shuffling gait, aphasia) symptoms, and corpus callosum agenesis. Clinicians have observed that recovery post-traumatic brain injury (TBI) varies among the population. This variability may be explained by the genetic differences present in the general population. In this study, we utilized a novel mouse model of L1 syndrome with a mutation at aspartic acid position 201 in the extracellular domain of L1 (L1-201). We assessed the impact of this specific single nucleotide polymorphism (SNP) localized to the X-chromosome gene on recovery outcomes following TBI by comparing the L1-201 mouse mutants with their wild-type littermates. We demonstrate that male L1-201 mice exhibit significantly worse learning and memory outcomes in the Morris water maze after lateral fluid percussion (LFP) injury compared to male wild-type mice and a trend to worse motor function on the rotarod. However, no significant changes were observed in markers for inflammatory responses or apoptosis after TBI.
Topics: Humans; Male; Animals; Mice; Neural Cell Adhesion Molecule L1; Neurodegenerative Diseases; Polymorphism, Single Nucleotide; Hydrocephalus; Brain Injuries, Traumatic; Intellectual Disability; Spastic Paraplegia, Hereditary; Genetic Diseases, X-Linked
PubMed: 38474289
DOI: 10.3390/ijms25053043 -
Cureus May 2024In right-handed individuals, aphasia resulting from right hemisphere damage is termed crossed aphasia and has a very low occurrence rate. Additionally, aphasia due to...
In right-handed individuals, aphasia resulting from right hemisphere damage is termed crossed aphasia and has a very low occurrence rate. Additionally, aphasia due to thalamic lesions often involves hemorrhage, with infarction cases less frequently reported. We present the case of an 81-year-old right-handed female who developed aphasia due to a right thalamic infarction. She exhibited characteristics typical of thalamic aphasia observed in left thalamic lesions. Furthermore, jargon agraphia manifested during writing tasks. This may suggest disinhibition of the left hemisphere writing motor memory by the right hemisphere language function.
PubMed: 38903355
DOI: 10.7759/cureus.60637