Timing of Allocentric and Egocentric Spatial Processing in Human Intracranial EEG

0576097 - FGÚ 2024 RIV DE eng J - Journal Article
Moraresku, Sofiia - Hammer, J. - Janča, R. - Ježdík, P. - Kalina, A. - Marusič, P. - Vlček, Kamil
Timing of Allocentric and Egocentric Spatial Processing in Human Intracranial EEG.
Brain Topography. Roč. 36, č. 6 (2023), s. 870-889. ISSN 0896-0267. E-ISSN 1573-6792
R&D Projects: GA ČR(CZ) GA19-11753S
Institutional support: RVO:67985823
Keywords : intracranial EEG * high-frequency gamma activity * reference frames * allocentric * egocentric * spatial judgment
OECD category: Neurosciences (including psychophysiology
Impact factor: 2.7, year: 2022
Method of publishing: Open access
https://doi.org/10.1007/s10548-023-00989-2

Spatial reference frames (RFs) play a key role in spatial cognition, especially in perception, spatial memory, and navigation. There are two main types of RFs: egocentric (self-centered) and allocentric (object-centered). Although many fMRI studies examined the neural correlates of egocentric and allocentric RFs, they could not sample the fast temporal dynamics of the underlying cognitive processes. Therefore, the interaction and timing between these two RFs remain unclear. Taking advantage of the high temporal resolution of intracranial EEG (iEEG), we aimed to determine the timing of egocentric and allocentric information processing and describe the brain areas involved. We recorded iEEG and analyzed broad gamma activity (50-150 Hz) in 37 epilepsy patients performing a spatial judgment task in a three-dimensional circular virtual arena. We found overlapping activation for egocentric and allocentric RFs in many brain regions, with several additional egocentric- and allocentric-selective areas. In contrast to the egocentric responses, the allocentric responses peaked later than the control ones in frontal regions with overlapping selectivity. Also, across several egocentric or allocentric selective areas, the egocentric selectivity appeared earlier than the allocentric one. We identified the maximum number of egocentric-selective channels in the medial occipito-temporal region and allocentric-selective channels around the intraparietal sulcus in the parietal cortex. Our findings favor the hypothesis that egocentric spatial coding is a more primary process, and allocentric representations may be derived from egocentric ones. They also broaden the dominant view of the dorsal and ventral streams supporting egocentric and allocentric space coding, respectively.
Permanent Link: https://hdl.handle.net/11104/0346280