2025 Hyper Recent •CC0 1.0 Universal

This work is dedicated to the public domain. No rights reserved.

Access Preprint From Server
April 21st, 2025
Version: 1
University of Tubingen
neuroscience
biorxiv

Plasticity of interhemispheric motor cortex connectivity induced by brain state-dependent cortico-cortical paired-associative stimulation

Ermolova, M.Open in Google Scholar•Kozak, G.Open in Google Scholar•Belardinelli, P.Open in Google Scholar•Ziemann, U.Open in Google Scholar

Transcallosal connectivity between the hand areas of the two primary motor cortices (M1) is important for coordination of unimanual and bimanual hand motor function. Effective connectivity of this M1-M1 pathway can be tested in the form of short-interval interhemispheric inhibition (SIHI) using dual-coil transcranial magnetic stimulation (TMS). Recently, we and others have demonstrated that the phase of the ongoing sensorimotor -rhythm has significant impact on corticospinal excitability as measured by motor evoked potential (MEP) amplitude, and repetitive TMS of the high-excitability state (trough of the -rhythm) but not other states resulted in long-term potentiation-like MEP increase. Here, we tested to what extent the phase of the ongoing -rhythm in the two M1 cortices affects long-term change in SIHI. In healthy subjects we applied cortico-cortical paired associative stimulation (ccPAS) in four different -phase conditions in the left conditioning M1 and right test M1 (trough-trough, trough-positive peak, positive peak-trough, random phase). We found long-term strengthening of SIHI but no differential effect of phase conditions. Findings point to a distinct regulation of plasticity of corticospinal vs. M1-M1 connectivity. The observed ccPAS-induced strengthening of effective M1-M1 connectivity (SIHI) may be utilized for therapeutic applications that potentially benefit from modification of interhemispheric excitation/inhibition balance.

Similar Papers

biorxiv
Mon Apr 21 2025
Inharmonicity enhances brain signals of attentional capture and auditory stream segregation
Harmonicity is an important feature for auditory perception as it influences pitch processing, memory and hearing in noisy environments. However, the neural substrates of processing harmonic and inharmonic sounds remain unclear. Here, we systematically manipulated the harmonicity of synthetic sounds by introducing random jittering to the frequencies above the fundamental. Using electroencephalogra...
Basinski, K.
•
Celma-Miralles, A.
•
Quiroga-Martinez, D. R.
•
Vuust, P.
biorxiv
Mon Apr 21 2025
All spectral frequencies of neural activity reveal semantic representation in the human anterior ventral temporal cortex
Intracranial electrophysiology offers a unique insight into the nature of information representation in the brain - it can be used to disentangle information encoded in local neuronal activity (gamma and high gamma frequencies) from information encoded via long-range interactions (lower frequencies). We used regularised logistic regression to decode animacy from time-frequency power and phase extr...
Frisby, S. L.
•
Halai, A. D.
•
Cox, C. R.
•
Clarke, A.
...•
Lambon Ralph, M. A.
biorxiv
Mon Apr 21 2025
Causal Contributions of Left Inferior and Medial Frontal Cortex to Semantic and Executive Control
Semantic control guides the targeted and context-based retrieval from semantic memory. The overlap with and dissociation from domain-general executive control in the frontal lobe remains contentious. Here, we used transcranial magnetic stimulation (TMS) to probe the functional relevance of the left inferior frontal gyrus (IFG) and pre-supplementary motor area (pre-SMA) for semantic and executive c...
Martin, S.
•
Ferrante, M.
•
Bruera, A.
•
Hartwigsen, G.
biorxiv
Mon Apr 21 2025
Flexible value coding in the mesolimbic dopamine system depending on internal water and sodium balance
Homeostatic imbalances elicit strong cravings, such as thirst and salt appetite, to restore equilibrium. Although midbrain dopaminergic neurons are known to encode the value of foods, their nutritional state-dependency remains unknown. Here, we show that the activity of the dopaminergic mesolimbic pathway flexibly expresses the positive and negative values of water and salt depending on the intern...
Ozawa, T.
•
Nakagawa, I.
•
Uchida, Y.
•
Abe, M.
...•
Hikida, T.
biorxiv
Mon Apr 21 2025
Opponent regulation of striatal output pathways by dopamine and serotonin
Classic theories propose opponent functions for striatal dopamine (DA) and serotonin (5-hydroxytryptamine; 5HT), with DA promoting approach and 5HT promoting patience or avoidance. How these neuromodulators regulate downstream circuits to achieve such antagonistic effects remains mysterious. Here, we mapped striatal 5HT receptor expression and recorded from genetically-identified striatal neurons ...
Pinto, D. F. C.
•
Guo, M. Y.
•
Morishita, W.
•
Pomrenze, M. B.
...•
Malenka, R. C.
biorxiv
Mon Apr 21 2025
Optogenetic Stimulation of Single Ganglion Cells in the Living Primate Fovea
Though the responses of the rich variety of retinal ganglion cells (RGCs) reflect the totality of visual processing in the retina and provide the sole conduit for those processed responses to the brain, we have much to learn about how the brain uses these signals to guide behavior. An impediment to developing a comprehensive understanding of the role of retinal circuits in behavior is the paucity ...
Murphy, P.
•
McGregor, J.
•
Xu, Z.
•
Merigan, W.
•
Williams, D.
biorxiv
Mon Apr 21 2025
Stroke Shifts Brain Dynamics Toward Criticality: Evidence from Intrinsic Neural Timescales
Stroke induces widespread disruptions to brain function, extending beyond focal lesions to alter the multiscale temporal dynamics that govern neural processing. These dynamics-operating across milliseconds to months-form a hierarchical architecture essential for communication, integration, and adaptive plasticity. While stroke is known to impair local neural activity, its effects on this temporal ...
Wu, K.
•
Jelfs, B.
•
Fang, Q.
•
Gollo, L. L.
biorxiv
Mon Apr 21 2025
Feature-dependent decorrelation of sound representations across the auditory pathway
Early studies on orientation selectivity in the visual cortex have suggested that sensory systems generate new feature representations at specific processing stages. Many observations challenge this view, but in the absence of systematic, multistage measurements, the logic of how feature tuning emerges remains elusive. Here, using a generic approach based on representational similarity analysis wi...
Gosselin, E.
•
Bagur, S.
•
Jamali, S.
•
Puel, J.-L.
...•
Bathellier, B.
biorxiv
Mon Apr 21 2025
Breaking the Link: Neural Dissociation of Attention and Working Memory through Inhibitory Control
Attention and working memory (WM) encoding have traditionally been considered inseparable processes with shared neural mechanisms. Here, using an innovative experimental design and a multimodal approach, we provide the first direct neural evidence that attention and WM encoding are dissociable. Functional MRI identifies the supramarginal gyrus (SMG) as the key region enabling this dissociation, wh...
Liu, Y.
•
Fu, Y.
•
Tang, E.
•
Wu, H.
...•
Qin, P.