Altered "neuronal avalanches"in brains of epilepsy patients tied to cognitive performance

New research by the Human Brain Project has found that in the brains of patients with epilepsy, changes in large scale neuronal activations can be detected in the brain’s resting state activity, even when no seizure is ongoing. The non-invasive approach could lead to a new method to aid epilepsy diagnostics.

The new findings stem from a collaboration was conducted and published in the journal Epilepsia, the study has compared high density electroencephalograms (EEG) of 37 patients with temporal lobe epilepsy with healthy controls.

This new method is capable of detecting relevant features of epilepsy by simply taking into account the basal functional organisation of the brain”. “Even while a seizure is not happening, the brain of a patient with epilepsy presents some alterations in its network dynamics at the whole-brain scale.

The researchers found that the alteration of the spreading of neuronal avalanches in temporal lobe epilepsy is clustered around those brain areas which are fundamental for seizure initiation and diffusion. This opens up the possibility to a new preliminary diagnostic method, especially important for the difficult cases where scalp EEG fails to detect seizures and additional investigations are necessary.

The results also detected a link between the alteration of the spreading of neuronal avalanche and memory, which is often impaired in patients with epilepsy. The temporal lobe is specifically associated with memorisation, and specific patterns of propagation at resting state could be altered by epilepsy. Hence the researchers suggested that these finding offer further evidence of the neurophysiological and neuropsychological relevance of neuronal avalanches.

Reference:

Altered “neuronal avalanches” in brains of epilepsy patients tied to cognitive performance; Epilepsia, DOI: 10.1111/epi.17551