Recruitment of the left precentral gyrus in reading epilepsy: A multimodal neuroimaging study

Abstract

PurposeIn a previous study, we investigated a 42-year-old male patient with primary reading epilepsy using continuous video-electroencephalography (EEG). Reading tasks induced left parasagittal spikes with a higher spike frequency when the phonological reading pathway was recruited compared to the lexical one. Here, we seek to localize the epileptogenic focus in the same patient as a function of reading pathway using multimodal neuroimaging.Methods and resultsThe participant read irregular words and nonwords presented in a block-design paradigm during magnetoencephalography (MEG), functional near-infrared spectroscopy (fNIRS), and functional magnetic resonance imaging (fMRI) recordings, all combined with EEG. Spike analyses from MEG, fNIRS, and fMRI–EEGs data revealed an epileptic focus in the left precentral gyrus, and spike localization did not differ in lexical and phonological reading.ConclusionThis study is the first to investigate ictogenesis in reading epilepsy during both lexical and phonological reading while using three different multimodal neuroimaging techniques. The somatosensory and motor control functions of the left precentral gyrus that are congruently involved in lexical as well as phonological reading can explain the identical spike localization in both reading pathways. The concurrence between our findings in this study and those from our previous one supports the role of the left precentral gyrus in phonological output computation as well as seizure activity in a case of reading epilepsy.

Symmetric Bilinear Regression for Signal Subgraph Estimation

“…This triangle subgraph may form a core anatomical circuit in the phonological reading pathway. These regions agree with the findings in neuroscience that the superior frontal gyrus is associated with word reading [30], left precentral gyrus is involved in phonological output [31] and the posterior cingulate cortex is associated with language comprehension [32]. Fig.…”