Distribution of scene-selective areas within the human visual cortex.

Panel A shows the group-averaged (n=14) response to ‘scenes > faces’ contrast (Experiment 1). Areas PPA/TPA, RSC/MPA and TOS/OPA are localized within the temporal, medial and posterior-lateral brain surfaces, respectively. To show consistency with our previous reports (Nasr et al., 2011), data from individual subjects was largely smoothed (FWHM=5mm) and the group-averaged maps were generated based on fixed-rather than random-effects (see also Figure 3). The resultant map was thresholded at p<10-25 and overlaid on the common brain template (fsaverage). Panel B shows the activity map in one randomly-selected subject (see also Figure 2), evoked in response to the same stimulus contrast as in Panel A. Here, the activity map was only minimally smoothed (FWHM=2mm). Consequently, multiple smaller scene-selective sites could be detected across the cortex, including PIGS (black arrowhead), located within the posterior intraparietal gyrus. Traditionally, these smaller activity patches are treated as noise in measurement and discarded. For ease in comparing the two panels, the individual’s data was also overlaid on the fsaverage.

Activity evoked by ‘scene > face’ contrast in seven individual subjects, other than the one shown in Figure 1.

Panel A shows the evoked activity in the right hemisphere of one individual subject. The inset shows the enlarged activity map within the intraparietal region. The three scene-selective areas, along with area PIGS, are indicated in the map with arrowheads. The location of adjacent sulci the parieto-occipital sulcus (POS), the intraparietal sulcus (IPS) and the calcarine sulcus (CS)) are also indicated in the inset. Panel B shows the result from six other individuals. In this panel, the first two columns show the activity within the left hemisphere, while the next two columns show the activity within the right hemisphere of the same subjects. In all subjects, PIGS is detectable bilaterally within the posterior portion of the intraparietal gyrus, near (but outside) the POS. For all of the subjects, threshold level was set at p<10-4. All activity maps were overlaid on the fsaverage to highlight the consistency in PIGS location across the subjects.

PIGS was detected in group-averaged activity maps across two non-overlapping populations.

Panel A shows the group-averaged activity, evoked within the intraparietal region of fourteen subjects who participated in Experiment 1. Panel B shows the group-averaged activity, evoked within the intraparietal region of thirty-one subjects who participated in Experiment 4. Importantly, PIGS was evident in both groups bilaterally in the corresponding location (black arrows). Thus, despite its small size, this area was detectable even in the group-averaged activity maps based on large populations. Notably, in both panels, maps were generated based on random-effects, after correction for multiple comparisons. In both maps, the location of RSC/MPA and TOS/OPA are respectively indicated with white and green arrowheads.

PIGS was detected consistently across sessions.

Panel A shows the stimuli used for localizing PIGS during 7T scans. Stimuli including indoor, manmade outdoor and natural outdoor scenes and faces other than those used in Experiment 1. Panels B and C show the activity evoked by ‘scene > face’ contrast in the 3T scans (Experiment 1), overlaid on subjects own reconstructed brain (left hemisphere). Panel D shows the activity evoked by ‘scene > face’ contrast during 7T scans (Experiment 2). Despite the difference in scanners (3T vs. 7T) and stimuli, the location of PIGS remained mostly unchanged. Panel E shows the location of PIGS, measured in 3T (black dashed lines) and 7T (green dashed lines) relative to the location of area V6 (white arrowhead), localized functionally based on the response to ‘optic-flow > random motion’ (Experiment 3). In all subjects, the center of scene- and optic-flow-selective responses was adjacent, but not overlapping.

Area PIGS is located outside the POS and adjacent to the functionally-localized area V6.

Panels A and B show the probabilistic localization of areas PIGS and V6, respectively (see Methods). Panel C shows the probabilistic localization of areas RSC/MPA and TOS/OPA. All probability maps are thresholded at 20%-50% (red-to-yellow) and overlaid on the fsaverage. Panel D shows the relative location of these sites. Consistent with the results from the individual maps (Figure 4E), PIGS and V6 were located adjacent to each other, such that V6 was located within the POS and PIGS located outside the POS (within the intraparietal gyrus) with minimal overlap between the two regions.

Probabilistically generated labels can be used to detect PIGS.

Panel A shows the activity evoked by ‘scenes vs. faces’ stimuli, across PIGS, V6, RSC/MPA and TOS/OPA. Panel B shows the level of scene-selective activity, measured as ‘scene – face’, within these regions. Despite the small size of PIGS, the probabilistic label could detect the scene-selective activity within this area and the level of this activity was significantly higher than the adjacent area V6. In all panels, each dot represents the activity measured in one subject.

PIGS could also be detected based on the ‘scene > object’ contrast.

Panels A and D show the stimuli used in Experiments 5a and 5b respectively. Panels B and E show the activity maps evoked by ‘scene > object’ contrast in two different individuals who participated in Experiment 5a and 5b. Panels C and F show the activity maps evoked by and a different set of scenes and faces (used in Experiments 1 and 4) in the same individuals. The location of PIGS remained unchanged between the two maps.

The application of probabilistically generated labels to measure the PIGS response to ‘scene vs. object’ stimuli.

Panels A and C show the activity evoked by ‘scenes vs. object’ stimuli in Experiments 5a and 5b, respectively. Panels B and D show the level of scene-selective activity within the regions of interest. As in Experiment 4, the probabilistic label detected the scene-selective activity within PIGS and the level of this activity was significantly higher than the adjacent area V6. Other details are similar to Figure 6.

Example of stimuli used in Experiment 6.

Coherently-changing scenes implied ego-motion, as if the observer was jogging through a trail. Incoherently-changing scenes consisted of the same scene images as the coherently-changing scenes, but presented in a pseudo-random order. Face stimuli consisted of a mosaic of faces. These stimuli were different than those used in the previous experiments.

Scene-selective response to coherently- vs. incoherently-changing scenes within the intraparietal region (Experiment 6).

Panels A and B show respectively the group-averaged activity evoked by coherently- and incoherently-changing scenes relative to faces. Panel Cshows the group-averaged response evoked by the ‘coherently- > incoherently-changing scenes’ contrast. Among scene-selective areas, only PIGS showed significant sensitivity to the observer ego-motion. Besides PIGS, this contrast also evoked activity within area MT (cyan arrowhead), also more dorsal portions of the parietal cortex. Panel D shows the location of scene-selective areas in the same group of subjects based on an independent set of scene and face stimuli (Experiment 1), and generated based on random-effects. The location of PIGS (outside the POS) and RSC/MPA (within the POS) are indicated by black and white arrowheads, respectively. All maps were generated based on random-effects, after correction for multiple comparisons.

The scene-selective activity evoked within PIGS is influenced by the observer ego-motion.

Panel A shows the scene-selective activity evoked by the coherently- (red) and incoherently-changing scenes (blue), measured relative to the response to the faces, across areas PIGS, V6, RSC/MPA, TOS/OPA and PPA/TPA. Panel B shows the level of difference between the response evoked by ‘coherently- – incoherently-’ changing scenes across the regions of interest. While all regions showed a significantly stronger response to scenes compared to faces, PIGS showed the strongest impact of ego-motion on the scene-selective response. Other details are similar to Figure 6.

The group-averaged activity map evoked by the ‘biological > translational motion’ contrast.

Despite the low threshold used to generate these maps, we did not detect any significant activity evoked by the ‘biological > translational motion’ contrast within the PIGS and/or the other scene-selective areas. Rather, this contrast evoked a significant activity mainly within the inferior temporal sulcus (ITS), medial temporal sulcus (MTS) and superior temporal sulcus (STS).