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Functional differentiation in the human auditory and language areas revealed by a dichotic listening task.

The human auditory cortex plays a special role in speech recognition. It is therefore necessary to clarify the functional roles of individual auditory areas. We applied functional magnetic resonance imaging (fMRI) to examine cortical responses to speech sounds, which were presented under the dichotic and diotic (binaural) listening conditions. We found two different response patterns in multiple auditory areas and language-related areas. In the auditory cortex, the medial portion of the secondary auditory area (A2), as well as a part of the planum temporale (PT) and the superior temporal gyrus

Enhanced neural plasticity of the primary visual cortex in visual snow syndrome: evidence from magnetoencephalographic gamma oscillations.

Visual snow syndrome is a neurological disorder characterized by persistent visual disturbances and associated symptoms. Although the neural … terations in the excitation-inhibition balance and neuroplasticity in visual snow syndrome, we used magnetoencephalography to record visual gamma oscillations in 26 patients with this disorder and 27 healthy controls. Participants were exposed to repeatedly presented high-contrast annular gratings, which were either static or drifting at varying speeds to systematically …

Magnetoencephalographic study of hand and foot sensorimotor organization in 325 consecutive patients evaluated for tumor or epilepsy surgery.

OBJECTIVES: The presence of intracranial lesions or epilepsy may lead to functional reorganization and hemispheric lateralization. We applied a clinical magnetoencephalography (MEG) protocol for the localization of the contralateral and ipsilateral S1 and M1 of the foot and hand in patients with non-lesional epilepsy, stroke, developmental brain injury, traumatic brain injury and brain tumors. We investigated whether differences in activation patterns could be related to underlying pathology. METHODS: Using dipole fitting, we localized the sources underlying sensory and motor evoked magnetic …

Salience network hub dysfunction is associated with cognitive impairment in self-limited epilepsy with centrotemporal spikes: An OPM-MEG study.

OBJECTIVE: Self-limited epilepsy with centrotemporal spikes (SeLECTS), although characterized by well-controlled seizures, is frequently associated with persistent cognitive deficits in affected children. This study aimed to investigate whether hub dysfunction of the salience network (SN) is associated with cognitive impairment in SeLECTS, using optically pumped magnetometer- magnetoencephalography (OPM-MEG) within the framework of the triple network model (TNM), which encompasses the salience, default mode, and central executive networks (CENs). METHODS: This cross-sectional case-control stu…

Neurophysiological alterations in mice and humans carrying mutations in APP and PSEN1 genes.

BACKGROUND: Studies in animal models of Alzheimer's disease (AD) have provided valuable insights into the molecular and cellular processes underlying neuronal network dysfunction. Whether and how AD-related neurophysiological alterations translate between mice and humans remains however uncertain. METHODS: We characterized neurophysiological alterations in mice and humans carrying AD mutations in the APP and/or PSEN1 genes, focusing on early pre-symptomatic changes. Longitudinal local field potential recordings were performed in APP/PS1 mice and cross-sectional magnetoencephalography recordin…

Early top-down control of internal selection induced by retrospective cues in visual working memory: advantage of peripheral over central cues.

Attention can be deployed among external sensory stimuli or internal working memory (WM) representations, and recent primate studies have re … retro-cues) that induced attention selection among WM representations. To achieve this, we combined magnetoencephalography (MEG, Experiment 1) and transcranial magnetic stimulation (TMS, Experiment 2) with an orientation-recall paradigm. Experiment 1 found that a peripheral retro-cue with 100% reliability had a greater benefit on WM performance than a central retro-cue, …

Nonlinear interactions in the thalamocortical loop in essential tremor: A model-based frequency domain analysis.

There is increasing evidence to suggest that essential tremor has a central origin. Different structures appear to be part of the central tremorogenic network, including the motor cortex, the thalamus and the cerebellum. Some studies using electroencephalogram (EEG) and magnetoencephalography (MEG) show linear association in the tremor frequency between the motor cortex and the contralateral tremor electromyography (EMG). Additionally, high thalamomuscular coherence is found with the use of thalamic local field potential (LFP) recordings and tremulous EMG in patients undergoing surgery for dee…

Neural oscillations serving abstract reasoning are differentially associated with inflammatory markers in people with HIV.

INTRODUCTION: Despite living a normal lifespan, people with HIV (PWH) are at a much greater risk of developing cognitive impairment. While the precise mechanisms are not fully understood, persistently high inflammation levels are thought to be a key contributor, as multiple studies have linked cognitive impairment and elevated inflammation. In contrast, evidence of a relationship between neural function and inflammatory activity is extremely limited in PWH and/or controls. Thus, in the current study, we integrate state-of-the-art dynamic functional brain mapping with measures of three inflamma

A backward encoding approach to recover subcortical auditory activity.

Several subcortical nuclei along the auditory pathway are involved in the processing of sounds. One of the most commonly used methods of measuring the activity of these nuclei is the auditory brainstem response (ABR). Due to its low signal-to-noise ratio, ABR's have to be derived by averaging over activity generated by thousands of artificial sounds such as clicks or tone bursts. This approach cannot be easily applied to natural listening situations (e.g. speech, music), which limits auditory cognitive neuroscientific studies to investigate mostly cortical processes. We propose that by individ

Altered transient brain dynamics in multiple sclerosis: Treatment or pathology?

Multiple sclerosis (MS) is a demyelinating, neuroinflammatory, and -degenerative disease that affects the brain's neurophysiological functioning through brain atrophy, a reduced conduction velocity and decreased connectivity. Currently, little is known on how MS affects the fast temporal dynamics of activation and deactivation of the different large-scale, ongoing brain networks. In this study, we investigated whether these temporal dynamics are affected in MS patients and whether these changes are induced by the pathology or by the use of benzodiazepines (BZDs), an important symptomatic treat

Neural gain control measured through cortical gamma oscillations is associated with sensory sensitivity.

Gamma oscillations facilitate information processing by shaping the excitatory input/output of neuronal populations. Recent studies in humans and nonhuman primates have shown that strong excitatory drive to the visual cortex leads to suppression of induced gamma oscillations, which may reflect inhibitory-based gain control of network excitation. The efficiency of the gain control measured through gamma oscillations may in turn affect sensory sensitivity in everyday life. To test this prediction, we assessed the link between self-reported sensitivity and changes in magneto-encephalographic gamm

An examination of the effects of broadband air-conduction masker on the speech intelligibility of speech-modulated bone-conduction ultrasound.

Ultrasound can be heard by bone-conduction, and speech-modulated bone-conducted ultrasound (BCU) delivers the speech information to the human ear. One of the recognition mechanisms is the demodulation of the signals. Because some of the profoundly deaf can also hear speech-modulated BCU, another mechanism may also contribution to the recognition of speech-modulated BCU. In this study, eight volunteers with normal hearing participated. The intelligibilities of speech-modulated BCU were measured using a numeral word list under masking conditions. Because the masker can mask the demodulated sound

Redundancy as a graph-based index of frequency specific MEG functional connectivity.

We used a recently proposed graph index to investigate connectivity redundancy in resting state MEG recordings. Usually, brain network analyses consider indexes linked to the shortest paths between cerebral regions. However, important information might be lost about alternative trails by neglecting longer pathways. We measured the redundancy of the connectivity by considering the multiple paths at the global level (i.e., scalar redundancy), across different path lengths (i.e., vector redundancy), and between node pairs (i.e., matrix redundancy). We applied this approach to a robust frequency d

Unsupervised Subtyping of Focal Epilepsy IEDs via Graph-Based MEG Networks.

OBJECTIVE: Interictal epileptiform discharges (IEDs) are clinically important biomarkers in focal epilepsy, yet their source-level network organization and subtype structure remain insufficiently characterized. This study aimed to identify reproducible IED network subtypes from source-level magnetoencephalography (MEG) connectivity and to examine whether these subtypes capture clinically meaningful information related to MEGIEDlocalization. METHODS: Fifty-five patients with focal epilepsy were retrospectively included. After manual IED identification, source-level MEG signals were reconstruct…

Retraining dorsal visual pathways improves cognitive skills and executive control networks following mild traumatic brain injury.

BACKGROUND AND OBJECTIVES: Mild traumatic brain injury (mTBI) frequently results in persistent cognitive deficits with limited evidence-base … lective attention, and cognitive flexibility assessed via standardized neuropsychological measures. Magnetoencephalography (MEG) recordings during resting state and an N-Back task provided neurophysiological validation. RESULTS: PATH training yielded significantly greater VWM improvements (49%) compared to ReCollect (13%) and OD (8%) interventions. Repeated-measures AN …

Модуляция склона в результате выполнения задачи 1/f в качестве независимого от парадигмы маркера когнитивного контроля при множественном склерозе.

Множественный склероз (MS) — хроническое нервно-дегенеративное и воспалительное заболевание, вызывающее моторные, сенсорные и когнитивные расстройства, включая нарушения в памяти и внимании. Эти когнитивные дефициты могут возникать из-за дисбаланса между изнурительной и ингибиционной нейронной активностью из-за синаптических потерь. Недавние исследования свидетельствуют о том, что биомаркер для когнитивного контроля мог бы использоваться для определения баланса между апериментальным наклоном 1/f - нейронным маркером, отражающим возбуждение/ингибирование (E/I). В этом исследовании рассматривает

Совпадение в аннотации оригинала
Multiple sclerosis (MS) is a chronic neuro-degenerative and inflammatory disease causing motor, sensory, and cognitive deficits, including i … to investigate its potential as a paradigm-independent marker of cognitive control. We analyzed the Magnetoencephalography (MEG) data collected from 126 participants: 44 healthy controls (HCs), 61 people with MS not treated with benzodiazepines (pwMS(BZDn)), and 21 pwMS treated with benzodiazepines (pwMS(BZDp)). Participants performed an auditory oddball task and a visu …

Case report: Neural timing deficits prevalent in developmental disorders, aging, and concussions remediated rapidly by movement discrimination exercises.

BACKGROUND: The substantial evidence that neural timing deficits are prevalent in developmental disorders, aging, and concussions resulting from a Traumatic Brain Injury (TBI) is presented. OBJECTIVE: When these timing deficits are remediated using low-level movement-discrimination training, then high-level cognitive skills, including reading, attention, processing speed, problem solving, and working memory improve rapidly and effectively. METHODS: In addition to the substantial evidence published previously, new evidence based on a neural correlate, MagnetoEncephalography physiological reco…

Voxel-based morphometric MRI post-processing and PET/MRI co-registration reveal subtle abnormalities in cingulate epilepsy.

OBJECTIVE: Diagnostic challenges exist in the presurgical evaluation of patients with magnetic resonance imaging (MRI) negative cingulate ep … ed by comparison to ictal intracranial EEG findings. Other characteristics obtained from scalp EEG, magnetoencephalography (MEG), iEEG, and pathological study were also reported. RESULTS: Ten patients were included, of which eight were diagnosed with anterior CE, one with middle CE, and one with posterior CE. The semiology included fear, embarrassment, vocalization, ic …

The utility of arterial spin labeling in the presurgical evaluation of poorly defined focal epilepsy in children.

OBJECTIVE: The authors sought to assess the utility of arterial spin labeling (ASL) perfusion 3T-MRI for the presurgical evaluation of poorl … sults were prospectively compared to scalp EEG, structural 3T-MRI, FDG-PET, ictal/interictal SPECT, magnetoencephalography (MEG), and intracranial recording results, as well as the final surgically proven epileptogenic zone (EZ) in operated patients who had at least 1 year of good (Engel class I/II) seizure outcome and positive histopathology results. RESULTS: Qualitat …

Is intracranial electroencephalography useful for planning resective surgery in intractable epilepsy with ulegyria?

OBJECTIVE: Intractable epilepsy patients with ulegyria could be candidates for resective surgery. Complete resection of ulegyria in the epil … icated after comprehensive preoperative evaluations, including high-field MRI, long-term video-EEG, magnetoencephalography, and FDG-PET. The resection planning was based on iEEG analysis. Total lesionectomy was not always performed, as preservation of cortical function was prioritized. RESULTS: Ulegyria was seen in the occipital and/or parietal lobe in 9 patients and b …