Poster No:
992
Submission Type:
Abstract Submission
Authors:
Masakazu Sugimoto1,2, Ikko Kimura3, Masamichi Hayashi1,2
Institutions:
1Graduate School of Frontier Biosciences, Osaka University, Suita, Japan, 2Center for Information and Neural Networks, Advanced ICT Research Institute, National Institute of Information and Communications Technology, Suita, Japan, 3Laboratory for Brain Connectomics Imaging, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
First Author:
Masakazu Sugimoto
Graduate School of Frontier Biosciences, Osaka University|Center for Information and Neural Networks, Advanced ICT Research Institute, National Institute of Information and Communications Technology
Suita, Japan|Suita, Japan
Co-Author(s):
Ikko Kimura
Laboratory for Brain Connectomics Imaging, RIKEN Center for Biosystems Dynamics Research
Kobe, Japan
Masamichi Hayashi
Graduate School of Frontier Biosciences, Osaka University|Center for Information and Neural Networks, Advanced ICT Research Institute, National Institute of Information and Communications Technology
Suita, Japan|Suita, Japan
Introduction:
Processing time and space is critical for optimizing our perception and behavior in an ever-changing environment. The ability to process temporal and spatial information is highly variable across individuals. While both temporal and spatial processing are known to involve frontoparietal circuits (Hayashi et al., 2018; Sack et al., 2007), it is unclear whether an individual's ability to discriminate temporal and spatial information is reflected in brain structures. To identify the neuroanatomical correlates of temporal and spatial processing, here we investigated whether interindividual differences in duration and orientation estimation ability correlate with gray matter (GM) and white matter (WM) structures.
Methods:
Thirty-seven right-handed adults participated in three experimental sessions. In the first session, we collected structural (T1-weighted, 0.8 mm isotropic) and diffusion MRI (69 directions, 1.7 mm isotropic, b = 0, 700 and 2000) data using 3T MRI. In the following two sessions, we tested participants' spatiotemporal processing ability by measuring duration and orientation discrimination thresholds using the one-up-three-down staircase method, two times per session. In the duration task, two visual stimuli (i.e., black disks) were presented sequentially and participants judged whether the second disk was presented for a shorter or longer duration than the first. In the orientation task, two Gabor patches were presented sequentially and participants judged whether the orientation of the second stimulus was rotated clockwise or counterclockwise with respect to the first. The mean of the last six reversal points obtained in each measurement, which lasted 270 s for the duration task and 215 s for the orientation task, was averaged over the two measurements. Individual thresholds were then determined by averaging the mean thresholds collected over the two experimental sessions.
To identify the brain structures associated with the ability to process temporal and spatial information, we examined the correlations between individual differences in behavioral thresholds and regional GM volume and the two metrics of WM microstructural integrity, fractional anisotropy (FA) and mean diffusivity (MD), using SPM12 and FSL software.
Results:
Our analyses revealed that individuals with greater GM volume in the right inferior frontal operculum, left middle frontal gyrus, and right inferior temporal gyrus were associated with better duration discrimination abilities, whereas no correlations were found for any metrics of WM structure. In contrast, larger GM volumes in the left lingual gyrus, smaller GM volumes in the right superior occipital gyrus, and crus1 in the bilateral cerebellum were associated with better orientation discrimination thresholds. In addition, larger MD values of the WM structure in the left superior longitudinal fasciculus and the inferior fronto-occipital fasciculus were also associated with better orientation discrimination thresholds. Given the previous study showing that the inferior front-occipital fasciculus connects the lingual gyrus with the inferior frontal gyrus (Palejwala et al., 2021), our results suggest that this pathway may be critical for orientation discrimination. FA values were not associated with interindividual differences in orientation discrimination performance.
Conclusions:
Our study shows that individual differences in GM volume of frontal and temporal regions were associated with duration estimation performance. In contrast, GM volume of the occipital regions and bilateral cerebellum, as well as WM structures associated with left occipital-frontal pathways, were correlated with the ability to estimate orientation. In conclusion, our findings suggest that distinct GM and WM structures reflect interindividual differences in the ability to process temporal and spatial information.
Higher Cognitive Functions:
Space, Time and Number Coding 1
Novel Imaging Acquisition Methods:
Anatomical MRI 2
Diffusion MRI
Keywords:
Cortex
Perception
STRUCTURAL MRI
White Matter
1|2Indicates the priority used for review
Provide references using author date format
Hayashi, M. J., van der Zwaag, W., Bueti, D., & Kanai, R. (2018). Representations of time in human frontoparietal cortex. Communications Biology, 1(1), 1–10.
Sack, A. T., Kohler, A., Bestmann, S., Linden, D. E. J., Dechent, P., Goebel, R., & Baudewig, J. (2007). Imaging the brain activity changes underlying impaired visuospatial judgments: Simultaneous fMRI, TMS, and behavioral studies. Cerebral Cortex, 17(12), 2841–2852.
Palejwala, A. H., Dadario, N. B., Young, I. M., O’Connor, K., Briggs, R. G., Conner, A. K., O’Donoghue, D. L., & Sughrue, M. E. (2021). Anatomy and White Matter Connections of the Lingual Gyrus and Cuneus. World Neurosurgery, 151, e426–e437.