Abstracts

Propagation of Physiological High-frequency Oscillations

Abstract number : 1.022
Submission category : 1. Basic Mechanisms / 1C. Electrophysiology/High frequency oscillations
Year : 2022
Submission ID : 2203923
Source : www.aesnet.org
Presentation date : 12/3/2022 12:00:00 PM
Published date : Nov 22, 2022, 05:22 AM

Authors :
Yoshio Shiimoto, Medical Student – Yokohama City University; Riyo Ueda, MD, PhD – Wayne State University; Yongje Jeon, Medical Student – Yokohama City University; Kazuki Sakakura, MD – Wayne State University; Yu Kitazawa, MD, PhD – Wayne State University; Masaki Sonoda, MD, PhD – Assistant Professor, Yokohama City University; Eishi Asano, MD, MS, PhD – Professor, Wayne State University

Rationale: Epilepsy presurgical evaluation includes functional brain mapping to localize the eloquent areas. To this end, the measurement of task-related high-frequency oscillations (HFOs) is routinely employed in many tertiary epilepsy centers. The present study aimed to visualize and assess the propagation dynamics of task-related HFOs during a visuomotor task on an iPad.

Methods: We studied eight children with drug-resistant focal epilepsy who completed a one-back task implemented in the Lumosity cognitive game during extraoperative subdural EEG recording. Each participant was instructed to indicate, with a finger tapping, if a given visual stimulus was repeated or new. Time-frequency analysis quantified the percent change of HFO amplitude (70-110 Hz) at given electrode sites and 10-ms time bins. We built the whole-brain level video atlas animating the dynamics of task-related HFO modulations.

Results: Both repeated and new visual stimuli elicited HFO augmentation initially in the calcarine and subsequently in the fusiform region. Repeated stimulus-related HFO augmentation was confined to the posterior fusiform region at 100-230 ms post-stimulus onset. New stimulus-related HFO augmentation was likewise noted in the posterior fusiform region at the same time window but subsequently propagated anteriorly at 230-340 ms post-stimulus onset (Figure 1). Finger tapping-related HFO augmentation initially involved the contralateral precentral gyrus and propagated to the postcentral gyrus with an inter-gyral onset-to-onset delay of 100 ms (Figure 2).

Conclusions: The study provided preliminary evidence that the anterior fusiform region may support the recognition of new visual stimuli. Precentral-to-postcentral HFO propagation may reflect neural activations supporting motor execution followed by somatosensory, proprioceptive feedback. Video atlas may be a valuable tool to readily digest the propagation dynamics of neural activations supporting sensory and motor functions.

Funding: NIH grant NS64033 (to E. Asano)
Basic Mechanisms