A previously undescribed scene-selective site is the key to encoding ego-motion in naturalistic environments
Cite this dataset
Nasr, Shahin (2024). A previously undescribed scene-selective site is the key to encoding ego-motion in naturalistic environments [Dataset]. Dryad. https://doi.org/10.5061/dryad.xwdbrv1mj
Abstract
Current models of scene processing in the human brain include three scene-selective areas: the Parahippocampal Place Area (or the temporal place areas; PPA/TPA), the restrosplenial cortex (or the medial place area; RSC/MPA) and the transverse occipital sulcus (or the occipital place area; TOS/OPA). Here, we challenged this model by showing that at least one other scene-selective site can also be detected within the human posterior intraparietal gyrus. Despite the smaller size of this site compared to the other scene-selective areas, the posterior intraparietal gyrus scene-selective (PIGS) site was detected consistently in a large pool of subjects (n=59; 33 females). The reproducibility of this finding was tested based on multiple criteria, including comparing the results across sessions, utilizing different scanners (3T and 7T) and stimulus sets. Furthermore, we found that this site (but not the other three scene-selective areas) is significantly sensitive to ego-motion in scenes, thus distinguishing the role of PIGS in scene perception relative to other scene-selective areas. These results highlight the importance of including finer scale scene-selective sites in models of scene processing – a crucial step toward a more comprehensive understanding of how scenes are encoded under dynamic conditions.
README: A previously undescribed scene-selective site is the key to encoding ego-motion in naturalistic environments
https://doi.org/10.5061/dryad.xwdbrv1mj
3T and 7T functional MRI was used to study the functional organization of scene-selective cortical regions in the human brain. The focus of this study was to localize a previously undescribed scene-selective region within the posterior intraparietal gyrus (named PIGS) that responded selectively to ego-motion within naturalistic environments.
Description of the data and file structure
This dataset includes the stimuli (other than those published previously elsewhere), significance maps, generated probabilistic labels, and the measured activity across ROIS, as presented in Figures 1-13 in the corresponding article (Kennedy et al., 2024; eLife). Specifically:
Fig_1_maps folder contains the significance maps that show the distribution of scene-selective areas within the human visual cortex based on group-averaging (Fig_1A; fixed-effect) and in a single subject (Fig_1B).
Fig_2_maps folder contains the significance maps that show the distribution of scene-selective areas in 7 individual subjects other than those shown in Fig_1.
Fig_3_maps folder contains the significance maps that shows the distribution of scene-selective areas, in two different group of subjects, based on random-effects.
Fig_4_maps folder contains the significance maps that show the distribution of scene-selective areas in 4 different individuals based on the data collected in a high-resolution (7 Tesla) scanner. The maps should be overlaid on the subject's own reconstructed brain surfaces (see Subjects_Native_Sufaces.zip file). For Sbj1 and Sbj2, the significant maps should be overlaid on the left hemisphere. For Sbj 3 and Sbj4, the significance maps should be overlaid on the right hemisphere.
PIGS_ROI_Labels.zip contains the probabilistic labels that indicate the location of scene-selective areas within the human visual cortex (as demonstrated in Figure 5; Kennedy et al., 2024; eLife).
Fig_6_maps folder contains the results of retinotopic (polar angle) mapping in 2 subjects, using a 7 Tesla scanner. These maps should be overlaid on the subject's own reconstructed brains (right hemisphere). For the first map, overlay the activity map on Sbj5 saved within the Subjects_Native_Sufaces.zip file. For the second map, overlay the activity map on Sbj2 saved within the Subjects_Native_Sufaces.zip file.
Fig_7_Excel folder contains the data (saved in a excel file) that show the level of response (fmri signal change (%)) to scene and non-scene stimuli, across areas PIGS, V6, RSC and TOS, in 31 human adults. The variables are described in the first row of the excel sheet.
Fig_8_maps folder include the two set of significance maps: The first set (?h.Fig_8B and ?h.Fig_8E) that show the response to "scene>object" contrast in two individual participants. The second set (?h.Fig_8C and ?h.Fig_8F) show the activity evoked by "scene>object" contrast in the same individuals.
Fig_9_Excel contains the data (save in excel files) that show the fmri signal change (%) measured within PIGS, V6, RSC, and TOS in response to two different sets of scenes and objects. The variables are described in the first row of the excel sheet.
Fig_10_Stimuli folder contains the scene stimuli (jpg format) used to test the response to ego-motion within naturalistic scenes. Face stimuli cannot be shared publicly due to the copyright.
Fig_11_maps folder includes the significance maps that show the group-averaged activity evoked by coherently (Fig_11A) and incoherently (Fig_11B) changing scenes relative to faces. It also includes the significance maps that show the group-averaged response evoked by the ‘coherently > incoherently changing scenes’ contrast (Fig_11C). Lastly, it includes the significance maps that show the location of scene-selective areas in the same group of subjects based on an independent set of scene and face stimuli (Fig_11D).
Fig_12_Excel folder contains the data that show the fMRI signal change (%) measured within PIGS, V6, RSC, TOS, and PPA in response to coherently and incoherently changing scenes (relative to faces). The variables are described in the first row of the excel sheet.
Fig_13_maps folder contains the significance maps that show the group-averaged activity map evoked by the ‘biological > translational motion’ contrast.
Subjects_Native_Sufaces.zip contains the reconstructed brain surfaces for 4 individual subjects using freesurfer.
** activity maps and reconstructed brain surfaces can be viewed using freesurfer (freeview command).
** excel files can be viewed by using microsoft office.
** jpg file can be viewed by any image viewer (e.g. mspaint)
Sharing/Access information
https://mesovision.martinos.org/datasets
Code/Software
MATLAB (MathWorks; Natick, MA, USA) and the Psychophysics Toolbox (Brainard, 1997; Pelli, 1997) were used to control stimulus presentation. Freesurfer was used for generating the brain activity maps.
Methods
3T scans: In Experiments 1, 3a and 4-6, subjects were scanned in a horizontal 3T scanner (Tim Trio, Siemens Healthcare, Erlangen, Germany). Gradient echo EPI sequences were used for functional imaging. Functional data were acquired using single-shot gradient echo EPI with nominally 3.0 mm isotropic voxels (TR=2000 ms; TE=30 ms; flip angle=90°; band width (BW)=2298 Hz/pix; echo-spacing= 0.5 ms; no partial Fourier; 33 axial slices covering the entire brain; and no acceleration). During the first 3T scan (see the General Procedure), structural (anatomical) data were acquired for each subject using a 3D T1-weighted MPRAGE sequence (TR=2530 ms; TE=3.39 ms; TI=1100 ms; flip angle=7°; BW=200 Hz/pix; echo-spacing=8.2 ms; voxel size=1.0×1.0×1.33 mm).
7T scans: In Experiments 2 and 3b, subjects were scanned in a 7T Siemens whole-body scanner (Siemens Healthcare, Erlangen, Germany) equipped with SC72 body gradients (maximum gradient strength, 70 mT/m; maximum slew rate, 200 T/m/s) using a custom-built 32-channel helmet receive coil array and a birdcage volume transmit coil. Voxel dimensions were nominally 1.0 mm, isotropic. Single-shot gradient-echo EPI was used to acquire functional images with the following protocol parameter values: TR=3000 ms; TE=28 ms; flip angle=78°; BW=1184 Hz/pix; echo-spacing=1 ms; 7/8 phase partial Fourier; 44 oblique-coronal slices; and acceleration factor r=4 with GRAPPA reconstruction and FLEET-ACS data (Polimeni et al., 2015) with 10° flip angle. The field of view included the occipital-parietal brain areas to cover PIGS, RSC/MPA and TOS/OPA (but not PPA/TPA).
Funding
National Eye Institute, Award: R01EY030434
National Eye Institute, Award: R01EY017081