Background: Brain activity is constrained by and evolves over a network of structural and functional connections. Corticocortical evoked potentials (CCEPs) have been used to measure this connectivity and to discern brain areas involved in both brain function and disease. However, how varying stimulation parameters influences the measured CCEP across brain areas has not been well characterized.
Objective: To better understand the factors that influence the amplitude of the CCEPs as well as evoked gamma-band power (70-150 Hz) resulting from single-pulse stimulation via cortical surface and depth electrodes.
Methods: CCEPs from 4370 stimulation-response channel pairs were recorded across a range of stimulation parameters and brain regions in 11 patients undergoing long-term monitoring for epilepsy. A generalized mixed-effects model was used to model cortical response amplitudes from 5 to 100 ms post-stimulation.
Results: Stimulation levels <5.5 mA generated variable CCEPs with low amplitude and reduced spatial spread. Stimulation at ≥5.5 mA yielded a reliable and maximal CCEP across stimulation-response pairs over all regions. These findings were similar when examining the evoked gamma-band power. The amplitude of both measures was inversely correlated with distance. CCEPs and evoked gamma power were largest when measured in the hippocampus compared with other areas. Larger CCEP size and evoked gamma power were measured within the seizure onset zone compared with outside this zone.
Conclusion: These results will help guide future stimulation protocols directed at quantifying network connectivity across cognitive and disease states.
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http://dx.doi.org/10.1016/j.brs.2020.06.002 | DOI Listing |
Rev Gaucha Enferm
January 2025
RISE - Rede de Investigação em Saúde. Porto, Portugal.
Objective: To map the literature on the use of exergames in the rehabilitation of school-age children with brain tumors, in any context.
Method: Scoping review protocol developed using the recommendations of the Joanna Briggs Institute. The search will include aggregators, databases, indexes, repositories, and research browsers, without limitation as to the year of publication.
Oper Neurosurg (Hagerstown)
July 2024
Neurosurgical Simulation and Artificial Intelligence Learning Centre, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal , Quebec , Canada.
Background And Objectives: Subpial corticectomy involving complete lesion resection while preserving pial membranes and avoiding injury to adjacent normal tissues is an essential bimanual task necessary for neurosurgical trainees to master. We sought to develop an ex vivo calf brain corticectomy simulation model with continuous assessment of surgical instrument movement during the simulation. A case series study of skilled participants was performed to assess face and content validity to gain insights into the utility of this training platform, along with determining if skilled and less skilled participants had statistical differences in validity assessment.
View Article and Find Full Text PDFCurr Pain Headache Rep
January 2025
Department of Neurology, Danish Headache Center, Copenhagen University Hospital - Rigshospitalet, Valdemar Hansens Vej 5, Entrance 1A, 2600 Glostrup, Copenhagen, Denmark.
Purpose Of Review: To evaluate existing functional magnetic resonance imaging (fMRI) studies on post-traumatic headache (PTH) following traumatic brain injury (TBI).
Recent Findings: We conducted a systematic search of PubMed and Embase databases from inception to February 1, 2024. Eligible fMRI studies were required to include adult participants diagnosed with acute or persistent PTH post-TBI in accordance with any edition of the International Classification of Headache Disorders.
Brain Struct Funct
January 2025
Department of Psychiatry, Psychotherapy and Psychosomatics, School of Medicine, RWTH Aachen University, Aachen, Germany.
Physiological responses derived from audiovisual perception during assisted driving are associated with the regulation of the autonomic nervous system (ANS), especially in emergencies. However, the interaction of event-related brain activity and the ANS regulating peripheral physiological indicators (i.e.
View Article and Find Full Text PDFJ Neurol
January 2025
Western Institute of Neuroscience, Western University, London, Canada.
Background: Repeat neurological assessment is standard in cases of severe acute brain injury. However, conventional measures rely on overt behavior. Unfortunately, behavioral responses may be difficult or impossible for some patients.
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