Search results for "neurophysiolog"
showing 10 items of 228 documents
Evidence of resistance training-induced neural adaptation in older adults
2021
The deleterious effects of aging on force production are observable from the age of 40 upwards, depending on the measure. Neural mechanisms contributing to maximum force production and rate of force development have been suggested as descending drive from supraspinal centers, spinal motoneuron excitability, and corticospinal inhibition of descending drive; all of which influence motor unit recruitment and/or firing rate. Resistance-trained Master athletes offer a good source of information regarding the inevitable effects of aging despite the countermeasure of systematic resistance-training. However, most evidence of neural adaptation is derived from longitudinal intervention studies in pre…
Targeting Voltage-Dependent Calcium Channels with Pregabalin Exerts a Direct Neuroprotective Effect in an Animal Model of Multiple Sclerosis
2018
Background/aims Multiple sclerosis (MS) is a prototypical autoimmune central nervous system (CNS) disease. Particularly progressive forms of MS (PMS) show significant neuroaxonal damage as consequence of demyelination and neuronal hyperexcitation. Immuno-modulatory treatment strategies are beneficial in relapsing MS (RMS), but mostly fail in PMS. Pregabalin (Lyrica®) is prescribed to MS patients to treat neuropathic pain. Mechanistically, it targets voltage-dependent Ca2+ channels and reduces harmful neuronal hyperexcitation in mouse epilepsy models. Studies suggest that GABA analogues like pregabalin exert neuroprotective effects in animal models of ischemia and trauma. Methods We tested t…
26th Annual Computational Neuroscience Meeting (CNS*2017): Part 2
2017
International audience; No abstract available
Assessing sensory versus optogenetic network activation by combining (o)fMRI with optical Ca2+ recordings
2016
Encoding of sensory inputs in the cortex is characterized by sparse neuronal network activation. Optogenetic stimulation has previously been combined with fMRI (ofMRI) to probe functional networks. However, for a quantitative optogenetic probing of sensory-driven sparse network activation, the level of similarity between sensory and optogenetic network activation needs to be explored. Here, we complement ofMRI with optic fiber-based population Ca2+ recordings for a region-specific readout of neuronal spiking activity in rat brain. Comparing Ca2+ responses to the blood oxygenation level-dependent signal upon sensory stimulation with increasing frequencies showed adaptation of Ca2+ transient…
Transthyretin familial amyloid polyneuropathy (TTR‐FAP): Parameters for early diagnosis
2017
Abstract Background Familial transthyretin amyloidosis is a life‐threatening disease presenting with sensorimotor and autonomic polyneuropathy. Delayed diagnosis has a detrimental effect on treatment and prognosis. To facilitate diagnosis, we analyzed data patterns of patients with transthyretin familial amyloid polyneuropathy (TTR‐FAP) and compared them to polyneuropathies of different etiology for clinical and electrophysiological discriminators. Methods Twenty‐four patients with TTR‐FAP and 48 patients with diabetic polyneuropathy (dPNP) were investigated (neurological impairment score NIS; neurological disability score NDS) in a cross‐sectional design. Both groups were matched for gende…
Interhemispheric inhibition is dynamically regulated during action observation
2016
International audience; It is now well established that the motor system plays a pivotal role in action observation and that the neurophysiological processes underlying perception and action overlaps. However, while various experiments have shown a specific facilitation of the contralateral motor cortex during action observation, no information is available concerning the dynamics of interhemispheric interactions. The aim of the present study was, therefore, to assess interhemispheric inhibition during the observation of others' actions. We designed a transcranial magnetic stimulation (TMS) experiment in which we measured both corticospinal excitability and interhemispheric inhibition, this…
Left hemisphere enhancement of auditory activation in language impaired children
2019
| openaire: EC/H2020/641652/EU//ChildBrain Specific language impairment (SLI) is a developmental disorder linked to deficient auditory processing. In this magnetoencephalography (MEG) study we investigated a specific prolonged auditory response (N250m) that has been reported predominantly in children and is associated with level of language skills. We recorded auditory responses evoked by sine-wave tones presented alternately to the right and left ear of 9–10-year-old children with SLI (n = 10) and children with typical language development (n = 10). Source analysis was used to isolate the N250m response in the left and right hemisphere. In children with language impairment left-hemisphere …
Optogenetics: a new method for the causal analysis of neuronal networks in vivo
2012
Abstract The causal analysis of neuronal network function requires selective manipulations of genetically defined neuronal subpopulations in the intact living brain. Here, we highlight the method of optogenetics, which meets those needs. We cover methodological aspects, limitations, and practical applications in the field of neurosciences. The fundamentals of optogenetics are light-sensitive transmembrane channels and light-driven ion pumps, which can be genetically encoded, without requiring the application of exogenous cofactors. These opsins are expressed in neurons by means of viral gene transfer and cell-specific promoters. Light for stimulation can be non- or minimally invasively de…
Inflammatory polyradiculoneuropathies: Clinical and immunological aspects, current therapies, and future perspectives
2020
Inflammatory polyradiculoneuropathies are heterogeneous disorders characterized by immune-mediated leukocyte infiltration of peripheral nerves and nerve roots leading to demyelination or axonal degeneration or both. Inflammatory polyradiculoneuropathies can be divided into acute and chronic: Guillain–Barré syndrome and chronic inflammatory demyelinating polyneuropathy and their variants. Despite major advances in immunology and molecular biology have been made in the last years, the pathogenesis of these disorders is not completely understood. This review summarizes the current literature of the clinical features and pathogenic mechanisms of inflammatory polyradiculoneuropathies and focuses…
Linoleic acid: Is this the key that unlocks the quantum brain? Insights linking broken symmetries in molecular biology, mood disorders and personalis…
2017
Abstract In this paper we present a mechanistic model that integrates subneuronal structures, namely ion channels, membrane fatty acids, lipid rafts, G proteins and the cytoskeleton in a dynamic system that is finely tuned in a healthy brain. We also argue that subtle changes in the composition of the membrane’s fatty acids may lead to down-stream effects causing dysregulation of the membrane, cytoskeleton and their interface. Such exquisite sensitivity to minor changes is known to occur in physical systems undergoing phase transitions, the simplest and most studied of them is the so-called Ising model, which exhibits a phase transition at a finite temperature between an ordered and disorde…