Perilesional pathological oscillatory activity in the magnetoencephalogram of patients with cortical brain lesions

doi:10.1016/j.neulet.2003.10.065

Neuroscience Letters

Volume 355, Issues 1–2, 23 January 2004, Pages 93-96

https://doi.org/10.1016/j.neulet.2003.10.065 Get rights and content

Abstract

In the surrounding of focal ischemic brain lesions dysfunctional neuronal zones emerge often resulting in pathological oscillatory activity. Using whole-head magnetoencephalography we recorded brain activity during rest in 23 patients with ischemic cortical lesions to find out whether we can localise and characterise low-frequency oscillatory activity. We measured patients at different times after stroke and partly in a follow-up approach to determine the time course of slow-wave activity. Using the analysis tool Dynamic Imaging of Coherent Sources we computed tomographic maps of oscillatory power in the delta-band (0.5–3 Hz). Fifteen of 23 patients with cortical strokes showed delta-activity, which was localised in an area not more than 2 cm away from the lesion. We found this perilesional low-frequency activity in the acute as well as in the chronic stage of stroke. Follow-up measurements of individual patients revealed persistence of perilesional low-frequency activity for months and even years. No consistent relation between perilesional activity and clinical symptoms was observed. Our results indicate that perilesional delta activity is common after ischemic cortical stroke. However, the functional significance remains to be elucidated.

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Acknowledgements

This study was supported by the Deutsche Forschungsgemeinschaft (SFB194 Z2) and the VolkswagenStiftung.

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Perilesional pathological oscillatory activity in the magnetoencephalogram of patients with cortical brain lesions

Abstract

Section snippets

Acknowledgements

122-channel SQUID instrument for investigating the magnetic signals from the human brain

Physica Scripta

Synchronous neuronal activity is a signal for axonal sprouting after cortical lesions in the adult

J. Neurosci.

The motor syndrome associated with exaggerated inhibition within the primary motor cortex of patients with hemiparetic

Brain

The localization of spontaneous brain activity: first results in patients with cerebral tumors

Clin. Neurophysiol.

Sources of abnormal EEG activity in brain infarctions

Clin. Electroenceph.

Brain lesions that produce delta waves in the EEG

Neurology

Dynamic imaging of coherent sources: studying neural interactions in the human brain

Proc. Natl. Acad. Sci. USA