Search results for "PLASTICITY"

Neurophysiological Changes After Paired Brain and Spinal Cord Stimulation Coupled With Locomotor Training in Human Spinal Cord Injury

2021

Neurophysiological changes that involve activity-dependent neuroplasticity mechanisms via repeated stimulation and locomotor training are not commonly employed in research even though combination of interventions is a common clinical practice. In this randomized clinical trial, we established neurophysiological changes when transcranial magnetic stimulation (TMS) of the motor cortex was paired with transcutaneous thoracolumbar spinal (transspinal) stimulation in human spinal cord injury (SCI) delivered during locomotor training. We hypothesized that TMS delivered before transspinal (TMS-transspinal) stimulation promotes functional reorganization of spinal networks during stepping. In this p…

The effects of motor imagery and Paired associative stimulation on cortical excitability

2009

ABSTRACT Kumpulainen, Susanne 2009. The effect of PAS and motor imagery on the excitability of the motor cortex. Department of Biology of Physical Activity, University of Jyväskylä. Master’s theses of biomechanics. 41 pages. The plasticity of the brain is an increasingly important topic for physical therapists interested in (re)learning and repair following injury. A number of potential endogenous and exogenous protocols have been developed with the improved understanding of the mechanisms of synaptic plasticity. The purpose of this study was twofold: First, the effect of motor imagery of plantarflexion on motor cortex excitability was investigated since it has been shown that motor imagery…

Modulation of plasticity of the soleus area of the motor cortex using paired associative stimulation

2015

Paired associative stimulation (PAS) repeatedly combines single somatosensory nerve stimuli with single transcranial magnetic stimuli to induce bidirectional changes in the excitability of the cortical projections to the target muscle. PAS and motor training have been shown to share common neural mechanisms, suggesting that PAS tests functionally relevant neuronal circuits. While PAS has been used extensively to target the hand area of the motor cortex, few studies have targeted the leg area of the motor cortex. The optimal interstimulus inter- val (ISI) to induce plasticity in the cortical projections to lower limbs is still not well established. Thus, the first purpose of this thesis was …

The effect of paired associative stimulation-induced long-term potentiation-like plasticity on visuomotor learning

2014

Aivojen hermostollisissa rakenteissa ja toiminnassa tapahtuu adaptaatiota motorisen oppimisen seurauksena. Eräs ehdotetuista malleista, johon muutokset voivat perustua on hermoliitoksen voimakkuuden pitkäaikainen tehostuminen eli pitkäkestoinen potentiaa-tio (LTP). Keinotekoisesti LTP:n kaltainen vaikutus voidaan tuottaa parillisella as-sosiatiivisella stimulaatiolla (PAS). Lisäksi tutkimustulokset osoittavat, että PAS voi parantaa tietyn tyyppistä motorista oppimista. Tämän tutkimuksen tarkoituksena on sel-vittää miten PAS:n tuottama LTP:n kaltainen plastisuus vaikuttaa visuomotorisen oppi-misen alkuvaiheeseen. Visuomotorinen oppimistehtävä suoritettiin kolme kertaa PAS:n jälkeen. Oppimist…

Induction of neuronal plasticity during adulthood. Role of cortical interneurons and plasticity-related molecules.

2019

La complejidad del sistema nervioso de los vertebrados representa un reto a la hora de conocer su funcionamiento. Hace ya más de cien años que se postuló la neurona como unidad básica de procesamiento, generación y transmisión de la información a través de este sistema, y, con el paso de los años, ha evolucionado el conocimiento sobre esta unidad funcional. La idea clásica del sistema nervioso central (SNC) adulto es la de un tejido asombrosamente interconectado y complejo, pero prácticamente inmutable y muy poco adaptable a los cambios. No obstante, esta visión se ha ido desplazando, formándose una nueva idea del SNC adulto que, aunque de manera más limitada que durante el desarrollo, tamb…

Can Oscillatory Alpha-Gamma Phase-Amplitude Coupling be Used to Understand and Enhance TMS Effects?

2019

Recent applications of simultaneous scalp electroencephalography (EEG) and transcranial magnetic stimulation (TMS) suggest that adapting stimulation to underlying brain states may enhance neuroplastic effects of TMS. It is often assumed that longer-lasting effects of TMS on brain function may be mediated by phasic interactions between TMS pulses and endogenous cortical oscillatory dynamics. The mechanisms by which TMS exerts its neuromodulatory effects, however, remain unknown. Here, we discuss evidence concerning the functional effects on synaptic plasticity of oscillatory cross-frequency coupling in cortical networks as a potential framework for understanding the neuromodulatory effects o…

Plasticity

2020

Although the expression πλαστική τέχνη [plastic art] has Greek origins, the derivative term “plasticity” enters the European languages only in the Modern Age. The term has a double meaning: it indicates, at the same time, the art of manipulating a ductile substance and the ability to transform oneself to recreate formal qualities in response to external events (positive meaning of plasticity) or to cancel pre-existing formal configurations, originating morphological novelties (negative meaning of plasticity). For this reason, the birthplace of plasticity is the domain of art but the term is used with different connotations also in the morphological, physicochemical and medical fields.

Mechanizm neuroplastyczności i jego znaczenie dla psychoterapii oraz oceny jej skuteczności

2016

The paper introduces the mechanism of neuroplasticity, specifically the ability of the brain to develop new neurons (neurogenesis) and new connections between nerve cells (synaptogenesis) and to develop glial cells. The author presents the evidence proving the existence of neuroplasticity by giving examples of people with serious brain damage who function normally and, above all, of people living with almost no brain or with one hemisphere, or with post-stroke defects. However, the main purpose of this paper is to present the current state of knowledge of the importance of the brain plasticity for the course of psychotherapy, as well as for assessing its effectiveness. The author gives many…

Termodinamica e Funzioni Mentali Complesse

2010

Measuring phenotypes in fluctuating environments

2020

Despite considerable theoretical interest in how the evolution of phenotypic plasticity should be shaped by environmental variability and stochasticity, how individuals actually respond to these aspects of the environment within their own lifetimes remains unclear. We propose that this understanding has been hampered by experimental approaches that expose organisms to fluctuating environments (typically treatments where fluctuations in the environment are cyclical vs. erratic) for a pre‐determined duration, while ensuring that the mean environment over that the entire exposure period is invariable. This approach implicitly assumes that responses to the mean and variance/predictability in th…