6 research outputs found
Movement-related beta and gamma synchronization of the supplementary and primary motor cortex measured in epilepsy patients during longterm video EEG monitoring with subdural electrodes [Abstract]
Introduction: Exploration of sensorimotor integration processes during movement regulation is crucial to understand the pathophysiology of movement disorders and the effect of neuromodulation therapy. In Parkinson’s disease, dysfunction of supplementary motor cortex (SMA) has a primary role in evoking typical symptoms. In this study we detected post-movement beta (PMBS) and gamma synchronization of the SMA and primary motor cortex with electrocorticography (ECoG) in patients with epilepsy. PMBS is an electrophysiological indicator of sensorimotor integration, its parameters alter differently in several movement disorders.
Methods: ECoG in 3 patients with epilepsy was recorded during invasive preoperative long-term video EEG monitoring through subdural strip and grid electrodes placed on the SMA and lobulus paracentralis and the representation field of the hand area in the primary motor cortex. Patients were requested in the interictal period to repeat short flexions of each thumb thirty times voluntarily; the trials were averaged with respect to the offset of the brisk movements. Time-frequency analysis of power was performed with multitaper method.
Results: Post-movement synchronization could be detected mainly in the gamma frequency band above SMA and in the beta band above primary motor cortex. Latencies of post-movement synchronization varied in the SMA and primary motor cortex.
Conclusions: Activity of the SMA in the two hemispheres cannot be detected with electroencephalography or magnetoencephalography. In our study we showed the first time that post-movement synchronization appears mainly in the gamma band in the SMA. Evaluation of the latencies supports the hypothesis that post-movement synchronization indicates a motor network activity
Knowledge for Change: A Decade of Citizen Science (2020–2030) in Support of the SDGs
In October 2020, the Museum für Naturkunde Berlin (MfN) with many partners, supported by the European Commission and the Federal Ministry of Education and Research (BMBF), held an international, hybrid conference in order to showcase, evaluate, and discuss the contribution of citizen science to frame and achieve the SDGs. The conference Knowledge for Change: A Decade of Citizen Science (2020-2030) in Support of the SDGs took place as an official event of Germany’s 2020 EU Council presidency.
The SDGs are a scientifically based framework for the whole world to address hunger and malnutrition, health, environment as well as culture and justice, decided by the UN. Citizen Science, the contribution of lay people to scientific activities, may support the achievement of the SDGs – by providing data and insights, but also by adapting and prioritising research questions.
Aim
The conference presented, evaluated and discussed the exciting contributions that Citizen Science makes in framing and achieving sustainable development, specifically the UN SDGs. The conference brought together expertise from policy makers, institutional and citizen scientists, economists, NGOs and civil society to implement mechanisms and processes for the transition towards a more sustainable future.
The Declaration
A Declaration including policy recommendations resulted from the conference: "Our world – our goals: citizen science for the Sustainable Development Goals". The Declaration acts as a voluntary commitment by all partners to define the roles, competences and concrete potentials of Citizen Science to advance the SDGs. It was formulated in an open and participatory process.
The Declaration groups the various important contributions of citizen science to the SDGs in three central recommendations:
1) Harness the benefits of citizen science for the SDGs,
2) strengthen citizen science and its connections with other communities, and
3) strengthen future citizen science systems
Increased interictal spike activity associated with transient slow wave trains during non-rapid eye movement sleep
Non-rapid eye movement (NREM) sleep is characterized by recurring transient events (Cyclic Alternating Patterns, CAP), some of which consist of increased slow wave activity (A1 subtype). Such transient slow-wave events may play an important role in NREM sleep regulation and are known to facilitate epileptiform activity. In our study we investigated the relationship between interictal spike activity and Cyclic Alternating Patterns in three epileptic patients, using simultaneous scalp electroencephalogram (EEG) recording and intracranial electrocorticography. A significant increase of interictal activity was found during CAP A1 subtypes. A positive correlation between scalp EEG delta power and spike activity was found only in CAP A1 subtypes, but not during other events. These results show that transient (but not subcontinuous) delta activity has a facilitating effect on epileptoform activity, also suggesting a functional dissociation between morphologically similar delta activities.Péter Przemyslaw Ujma, Péter Simor, Raffaele Ferri, Dániel Fabó, Anna Kelemen, Loránd Erőss, Róbert Bódizs, and Péter Halás
Intracortical Mechanisms of Single Pulse Electrical Stimulation (SPES) Evoked Excitations and Inhibitions in Human
Cortico-cortical evoked potentials (CCEPs) elicited by single-pulse electric stimulation (SPES) are widely used to assess effective connectivity between cortical areas and are also implemented in the presurgical evaluation of epileptic patients. Nevertheless, the cortical generators underlying the various components of CCEPs in humans have not yet been elucidated. Our aim was to describe the laminar pattern arising under SPES evoked CCEP components (P1, N1, P2, N2, P3) and to evaluate the similarities between N2 and the downstate of sleep slow waves. We used intra-cortical laminar microelectrodes (LMEs) to record CCEPs evoked by 10 mA bipolar 0.5 Hz electric pulses in seven patients with medically intractable epilepsy implanted with subdural grids. Based on the laminar profile of CCEPs, the latency of components is not layer-dependent, however their rate of appearance varies across cortical depth and stimulation distance, while the seizure onset zone does not seem to affect the emergence of components. Early neural excitation primarily engages middle and deep layers, propagating to the superficial layers, followed by mainly superficial inhibition, concluding in a sleep slow wave-like inhibition and excitation sequence
Evoked effective connectivity of the human neocortex.
The role of cortical connectivity in brain function and pathology is increasingly being recognized. While in vivo magnetic resonance imaging studies have provided important insights into anatomical and functional connectivity, these methodologies are limited in their ability to detect electrophysiological activity and the causal relationships that underlie effective connectivity. Here, we describe results of cortico-cortical evoked potential (CCEP) mapping using single pulse electrical stimulation in 25 patients undergoing seizure monitoring with subdural electrode arrays. Mapping was performed by stimulating adjacent electrode pairs and recording CCEPs from the remainder of the electrode array. CCEPs reliably revealed functional networks and showed an inverse relationship to distance between sites. Coregistration to Brodmann areas (BA) permitted group analysis. Connections were frequently directional with 43% of early responses and 50% of late responses of connections reflecting relative dominance of incoming or outgoing connections. The most consistent connections were seen as outgoing from motor cortex, BA6-BA9, somatosensory (SS) cortex, anterior cingulate cortex, and Broca's area. Network topology revealed motor, SS, and premotor cortices along with BA9 and BA10 and language areas to serve as hubs for cortical connections. BA20 and BA39 demonstrated the most consistent dominance of outdegree connections, while BA5, BA7, auditory cortex, and anterior cingulum demonstrated relatively greater indegree. This multicenter, large-scale, directional study of local and long-range cortical connectivity using direct recordings from awake, humans will aid the interpretation of noninvasive functional connectome studies. Hum Brain Mapp, 2014. © 2014 Wiley Periodicals, Inc