Print  Close

Filler word-related high-gamma modulations in the left inferior frontal gyrus

Poster No:

2615 

Submission Type:

Abstract Submission 

Authors:

Ayame Yamagishi1, Yu Kitazawa2,3, Riri Kimura1, Risa Hikino1, Hiroshi Uda3,4, Naoto Kuroda3,5, Shin-ichiro Osawa5,6, keiya Iijima7, Kyoko Suzuki8, Nobukazu Nakasato5, Masaki Iwasaki7, Eishi Asano3,9

Institutions:

1Department of Medicine, Yokohama City University, Yokohama, Japan, 2Department of Neurology and Stroke Medicine, Yokohama City University, Yokohama, Japan, 3Department of Pediatrics, Children’s Hospital of Michigan, Detroit Medical Center, Wayne State University, Detroit, MI, 4Department of Neurosurgery, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan, 5Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Japan, 6Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan, 7Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Tokyo, Japan, 8Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan, 9Department of Neurology, Children’s Hospital of Michigan, Detroit Medical Center, Wayne State University, Detroit, MI

First Author:

Ayame Yamagishi  
Department of Medicine, Yokohama City University
Yokohama, Japan

Co-Author(s):

Yu Kitazawa  
Department of Neurology and Stroke Medicine, Yokohama City University|Department of Pediatrics, Children’s Hospital of Michigan, Detroit Medical Center, Wayne State University
Yokohama, Japan|Detroit, MI
Riri Kimura  
Department of Medicine, Yokohama City University
Yokohama, Japan
Risa Hikino  
Department of Medicine, Yokohama City University
Yokohama, Japan
Hiroshi Uda  
Department of Pediatrics, Children’s Hospital of Michigan, Detroit Medical Center, Wayne State University|Department of Neurosurgery, Osaka Metropolitan University Graduate School of Medicine
Detroit, MI|Osaka, Japan
Naoto Kuroda  
Department of Pediatrics, Children’s Hospital of Michigan, Detroit Medical Center, Wayne State University|Department of Epileptology, Tohoku University Graduate School of Medicine
Detroit, MI|Sendai, Japan
Shin-ichiro Osawa  
Department of Epileptology, Tohoku University Graduate School of Medicine|Department of Neurosurgery, Tohoku University Graduate School of Medicine
Sendai, Japan|Sendai, Japan
keiya Iijima  
Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry
Tokyo, Japan
Kyoko Suzuki  
Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine
Sendai, Japan
Nobukazu Nakasato  
Department of Epileptology, Tohoku University Graduate School of Medicine
Sendai, Japan
Masaki Iwasaki  
Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry
Tokyo, Japan
Eishi Asano  
Department of Pediatrics, Children’s Hospital of Michigan, Detroit Medical Center, Wayne State University|Department of Neurology, Children’s Hospital of Michigan, Detroit Medical Center, Wayne State University
Detroit, MI|Detroit, MI

Introduction:

The left inferior frontal gyrus (IFG) is believed to play an essential role in extracting meaningful words relevant to verbal questions. Previous studies reported neural activation in the left IFG prior to speech production.1,2 However, the temporal characteristics of left IFG activation related to utterance of filler words like "um" and "y'know" remains uncertain. We conducted research on filler-related high-gamma modulations to clarify when the left IFG is activated during use of filler words.

Methods:

We studied 40 right-handed Japanese-speaking patients with drug-resistant focal epilepsy who underwent intracranial EEG (iEEG) recording followed by surgical resection. During the iEEG recording, participants performed an auditory descriptive naming task consisting of 96 questions. We excluded trials in which patients didn't respond to the question or stated "I have no idea" from the analysis. To characterize the dynamics of left IFG high-gamma modulations (70-110 Hz) associated with filler words and question answers, we conducted a time-frequency analysis of the iEEG signals on 15 patients who uttered filler words ten or more times during the naming task. The baseline period was set from 600 to 400 ms before the question onset, and we determined when IFG high-gamma activity was augmented as compared to the baseline.

Results:

Approximately 300-750 ms prior to the vocalization of filler words and answers, there was a significant increase in high-gamma activity in the left IFG. Further, a more pronounced high-gamma augmentation in the left IFG was observed following the filler word uses as compared to the answer vocalization (Figures 1 and 2).
Supporting Image: fig1_1130.jpg
Supporting Image: fig2.jpg
 

Conclusions:

Our investigation disclosed unique neural dynamics within the left IFG related to the utterance of filler words compared to question answers. The usage of filler words might signal increased neural requirements within the left IFG, implying that the utterance of such words necessitates the engagement of this region for lexical retrieval efforts.

Language:

Language Comprehension and Semantics
Speech Production 2

Neuroinformatics and Data Sharing:

Brain Atlases

Novel Imaging Acquisition Methods:

EEG

Physiology, Metabolism and Neurotransmission :

Neurophysiology of Imaging Signals 1

Keywords:

Atlasing
Electroencephaolography (EEG)
Epilepsy
Language
Other - Left inferior frontal gyrus; functional mapping; filler words; intracranial EEG; high-gamma

1|2Indicates the priority used for review

Provide references using author date format

Nakai Y, et al. Three- and four-dimensional mapping of speech and language in patients with epilepsy. Brain. 2017;140:1351-1370.
Kitazawa Y, et al. Intra– and inter–hemispheric network dynamics supporting object recognition and speech production. NeuroImage. 2023;270:119954.