Article Figures & Data
Figures
- Figure 1.
Stimuli and experimental design of Experiment 1 (category selectivity). a, Examples of the stimuli used in Experiment 1. The stimuli consisted of the following three categories: scenes, faces, and objects. Scenes were selected from the following six categories: churches, concert halls, living rooms, beaches, mountains, and deserts (top row, four categories are depicted here). The face stimuli comprised Asian and Caucasian, male and female faces presented in front view (middle row). The objects consisted of dressers, vases, motorbikes, and roller skates (bottom row). Note that in total there were 48 unique exemplars within each visual category. b, Participants viewed the stimuli and performed a simple one-back task, responding whenever the same image was presented twice in a row (in this example, the second presentation of the vase). The stimuli were presented pseudorandomly, with a trial beginning with the presentation of a scene image for 500 ms followed by a blank gray screen for the following 500 ms. c, Schematic representation of the 64 electrode sites from which EEG activity was recorded. The grouped electrodes are those analyzed in the 12 critical regions (see text for details).
- Figure 2.
Stimuli and experimental design of Experiment 2 (scene diagnostic properties). a, Full stimulus set. The stimulus set comprised 96 individual, highly detailed, and diverse real-world scene images from 16 basic-level scene categories (churches, concert halls, hallways, living rooms, forest canopies, canyons, caves, ice caves, cities, harbors, highways, suburbs, beaches, deserts, hills, and mountains), with six exemplars within each category spanning the following three diagnostic scene properties: spatial expanse (open, closed; the spatial boundary of the scene); relative distance (near, far; distance to the nearest foreground objects); and naturalness (or semantic content; man-made, natural). b, Participants viewed the stimuli while performing an orthogonal fixation cross task, in which they were required to report whether the horizontal or vertical bar of the central fixation cross lengthened on each trial. Scene stimuli were presented for 500 ms, with a jittered interstimulus interval ranging from 1000 to 3000 ms.
- Figure 3.
Experiment 1 results. a, Mean N1/170 and P2 peak amplitudes (left and right column, respectively) in response to scenes (red), faces (blue), and objects (green; peak amplitudes are plotted separately for each hemisphere, for the posterior lateral electrode sites. Error bars indicate the SEM. Significant differences (p < 0.05) between pairs of categories are denoted by asterisk. b, Group-averaged ERPs (n = 12) for the three categories (scenes in red, faces in blue, objects in green) for the left and right hemispheres (data are plotted for the posterior lateral sites). c, ERP difference waveforms depicting face sensitivity (blue, faces-objects) and scene sensitivity (red, scenes-objects) over time for the left and right hemispheres (data are plotted for the posterior lateral sites). The waveforms (solid lines) are presented with across-subjects 95% confidence intervals around them (light blue and red for face and scene sensitivity, respectively).
- Figure 4.
Group-averaged ERPs (n = 12) for the three diagnostic scene properties tested in Experiment 2, plotted for the left and right posterior lateral sites. Top row, Spatial expanse (open vs closed). Middle row, Naturalness (man-made vs natural). Bottom row, Distance (near vs far).
- Figure 5.
Grand average ERP analysis results for Experiment 2. a, Mean P2 peak amplitudes in response to open and closed scenes (orange and purple, respectively) presented separately for the man-made and natural scenes (left and right columns respectively). b, Mean P2 peak amplitudes in response to natural (green) and man-made scenes (cyan). c, Mean N1 peak amplitudes in response to natural (green) and man-made scenes (cyan). All data are plotted for the posterior lateral sites. Significant differences (p < 0.05) between pairs of categories are denoted by asterisk (error bars indicate between-subjects SE).
- Figure 6.
Image statistics analysis of the 96 scene stimuli used in Experiment 2. A, Local contrast statistics (left) CE and SC, and spatial frequency statistics (right) FI and FS (absolute values are plotted for clarity) for each of the 96 scenes, which are color coded by global categorical distinction. The local contrast and spatial frequency statistics describe two-dimensional spaces in which the scenes cluster by naturalness and spatial expanse, respectively. B, The distributions of man-made vs natural, and open vs closed scenes across the four different computational parameters. *p < 0.05. C, Explained variance (R 2) for a regression model consisting of combinations of local contrast statistics and behavioral naturalness ratings (Nr; left), and a model consisting of spatial frequency statistics and behavioral spatial expanse ratings (Or, right). D, Explained variance for a regression model consisting of all image statistics and all behavioral ratings. Note the change in y-axis compared with that in C.
Tables
Data structure Type of test Observed power (α = 0.05) a Four-factor, within-subject design: hemisphere, site, mediality, category Repeated-measures ANOVA 0.99 b One-way, within-subject design: category Repeated-measures ANOVA 0.40 c One-way, within-subject design: category Repeated-measures ANOVA 0.35 d Four-factor, within-subject design: hemisphere, site, mediality, category Repeated-measures ANOVA 0.99 e Two-factor, within-subject design: category, site Repeated-measures ANOVA 0.70 f Two-factor, within-subject design: category, site Repeated-measures ANOVA 0.40 g One-way, within-subject design: category Repeated-measures ANOVA 0.40 h One-way, within-subject design: category Repeated-measures ANOVA 0.40 i Category: faces/objects Paired t test 1.00 j Category: faces/scenes Paired t test 1.00 k Category: scenes/objects Paired t test 0.43 l Two-factor, within-subject design: category, site Repeated-measures ANOVA 0.70 m Four-factor, within-subject design: hemisphere, site, mediality, category Repeated-measures ANOVA 0.99 n Category: scenes/objects Paired t test 0.99 o Category: scenes/faces Paired t test 0.99 p Category: faces/objects Paired t test 0.78 q Site: posterior/central Paired t test 0.99 r Site: central/frontal Paired t test 0.99 s Two-factor, within-subject design: category, component Repeated-measures ANOVA 1.00 t One-way, within-subject design: category Repeated-measures ANOVA 1.00 u One-way, within-subject design: category Repeated-measures ANOVA 1.00 v Category: scenes/faces Paired t test 0.99 w Category: scenes/objects Paired t test 0.71 x Category: faces/objects Paired t test 0.61 y Category: faces/scenes Paired t test 0.96 z Category: faces/objects Paired t test 0.76 aa Category: scenes/objects Paired t test 0.12 ab One-way, within-subject design: category Repeated-measures ANOVA 1.00 ac Four-factor, within-subject design: hemisphere, site, mediality, category Repeated-measures ANOVA 0.99 ad Spatial expanse (natural scenes): closed/open Paired t test 0.65 ae Spatial expanse (man-made scenes): closed/open Paired t test 0.12 af Four-factor, within-subject design: hemisphere, site, mediality, category Repeated-measures ANOVA 0.99 ag Four-factor, within-subject design: hemisphere, site, mediality, category Repeated-measures ANOVA 0.99 ah One-way, within-subject design (left hemisphere):
distanceRepeated-measures ANOVA 0.99 ai One-way, within-subject design (right hemisphere):
distanceRepeated-measures ANOVA 0.90 aj Two-way, within-subject design (left hemisphere):
naturalness, distanceRepeated-measures ANOVA 0.99 ak Two-way, within-subject design (right hemisphere):
naturalness, distanceRepeated-measures ANOVA 0.99 al 4 computational variables (n = 96), 2 categorical labels (n = 96) Two-sampled Kolmogorov–Smirnov test (nonparametric) Not applicablea am 3 response variables (n = 96), 6 predictor variables (n = 96) Linear multiple regression (ordinary least squares) see Table 4b a95% confidence intervals on actual distribution means are reported in Results.
bPost hoc power and R 2 for all regression models are reported in Tables 4 and 5.
Factor df MSE (Greenhouse–Geisser) F Significance P1 peak amplitudes ANOVA Hemisphere 1,11 7.068 0.375 0.553 Category 2,22 5.658 0.504 0.605 Site 2,22 426.203 24.098 0.000 Mediality 1,11 30.689 12.779 0.004 Hemisphere × category 2,22 4.748 3.361 0.061 Hemisphere × site 2,22 3.296 0.265 0.637 Category × site 4,44 9.389 5.164 0.008 Hemisphere × category × site 4,44 0.273 0.301 0.748 Hemisphere × mediality 1,11 0.001 0.001 0.972 Category × mediality 2,22 2.630 3.557 0.054 Hemisphere × category × mediality 2,22 0.518 0.957 0.365 Site × mediality 2,22 8.268 4.748 0.046 Hemisphere × site × mediality 2,22 0.251 0.175 0.741 Category × site × mediality 4,44 0.401 1.384 0.265 Hemisphere × category × site × mediality 4,44 7.068 0.375 0.553 N1/170 peak amplitudes ANOVA Hemisphere 1,11 28.032 1.294 0.280 Category 2,22 19.794 1.806 0.189 Site 2,22 27.333 0.797 0.395 Mediality 1,11 4.458 0.674 0.429 Hemisphere × category 2,22 0.645 0.252 0.722 Hemisphere × site 2,22 0.149 0.023 0.942 Category × site 4,44 33.346 3.232 0.079 Hemisphere × category × site 4,44 0.413 0.328 0.746 Hemisphere × mediality 1,11 0.003 0.001 0.976 Category × mediality 2,22 7.202 4.454 0.026 Hemisphere × category × mediality 2,22 0.013 0.024 0.933 Site × mediality 2,22 0.958 0.232 0.669 Hemisphere × site × mediality 2,22 2.160 1.122 0.325 Category × site × mediality 4,44 9.107 7.708 0.002 Hemisphere × category × site × mediality 4,44 0.576 0.941 0.416 P2 peak amplitudes ANOVA Hemisphere 1,11 5.056 0.241 0.633 Category 2,22 131.532 10.925 0.001 Site 2,22 533.726 23.344 0.000 Mediality 1,11 17.776 1.309 0.277 Hemisphere × category 2,22 3.147 0.565 0.548 Hemisphere × site 2,22 5.497 1.375 0.271 Category × site 4,44 7.236 2.077 0.146 Hemisphere × category × site 4,44 0.422 0.536 0.650 Hemisphere × mediality 1,11 0.00002 0.000 0.999 Category × mediality 2,22 1.596 0.880 0.418 Hemisphere × category × mediality 2,22 0.741 0.982 0.387 Site × mediality 2,22 0.882 0.463 0.592 Hemisphere × site × mediality 2,22 0.738 0.823 0.434 Category × site × mediality 4,44 0.429 0.660 0.521 Hemisphere × category × site × mediality 4,44 0.548 1.968 0.146 Factor df MSE F Significance P2 peak amplitudes ANOVA Hemisphere 1,11 107.218 2.038 0.181 Naturalness 2,22 43.968 26.223 0.000 Distance 2,22 1.701 1.271 0.284 Spatial expanse 1,11 2.669 1.601 0.232 Hemisphere × naturalness 2,22 0.384 0.554 0.472 Hemisphere × distance 2,22 0.182 0.651 0.437 Naturalness × distance 4,44 0.935 0.438 0.522 Hemisphere × naturalness × distance 4,44 0.686 1.077 0.322 Hemisphere × spatial expanse 1,11 1.422 1.380 0.265 Naturalness × spatial expanse 2,22 6.076 4.593 0.055 Hemisphere × naturalness × spatial expanse 2,22 0.227 0.652 0.436 Distance × spatial expanse 2,22 5.997 2.331 0.155 Hemisphere × distance × spatial expanse 2,22 0.269 0.469 0.508 Naturalness × distance × spatial expanse 4,44 0.308 0.162 0.695 Hemisphere × naturalness × distance × spatial expanse 4,44 0.642 2.025 0.183 N1 peak amplitudes ANOVA Hemisphere 1,11 4.177 0.083 0.779 Naturalness 2,22 16.505 4.880 0.049 Distance 2,22 4.211 2.961 0.113 Spatial expanse 1,11 4.006 1.061 0.325 Hemisphere × naturalness 2,22 0.085 0.125 0.730 Hemisphere × distance 2,22 0.066 0.572 0.465 Naturalness × distance 4,44 0.605 0.251 0.626 Hemisphere × naturalness × distance 4,44 0.138 0.922 0.358 Hemisphere × spatial expanse 1,11 1.263 1.204 0.296 Naturalness × spatial expanse 2,22 1.700 0.480 0.503 Hemisphere × naturalness × spatial expanse 2,22 0.197 0.416 0.532 Distance × spatial expanse 2,22 1.283 0.562 0.469 Hemisphere × distance × spatial expanse 2,22 0.042 0.212 0.655 Naturalness × distance × spatial expanse 4,44 6.327 2.176 0.168 Hemisphere × naturalness × distance × spatial expanse 4,44 0.072 0.479 0.503 P1peak amplitudes ANOVA Hemisphere 1,11 34.138 0.878 0.369 Naturalness 2,22 6.338 3.015 0.110 Distance 2,22 1.310 0.834 0.381 Spatial expanse 1,11 0.695 0.295 0.598 Hemisphere × naturalness 2,22 0.049 0.058 0.813 Hemisphere × distance 2,22 3.033 10.917 0.007 Naturalness × distance 4,44 4.612 1.135 0.310 Hemisphere × naturalness × distance 4,44 4.332 4.680 0.053 Hemisphere × spatial expanse 1,11 1.265 1.018 0.335 Naturalness × spatial expanse 2,22 2.643 0.437 0.522 Hemisphere × naturalness × spatial expanse 2,22 0.137 0.585 0.460 Distance × spatial expanse 2,22 0.636 0.275 0.610 Hemisphere × distance × spatial expanse 2,22 0.254 0.298 0.596 Naturalness × distance × spatial expanse 4,44 4.428 2.703 0.128 Hemisphere × naturalness × distance × spatial expanse 4,44 0.005 0.010 0.921 P1peak amplitudes ANOVA: Post hoc testing of the hemisphere × naturalness × distance interaction Left hemisphere Naturalness 1,11 0.362 3.641 0.083 Distance 1,11 0.320 0.278 0.608 Naturalness × distance 1,11 0.001 0.001 0.975 Right hemisphere Naturalness 1,11 1.106 1.695 0.220 Distance 1,11 0.604 3.449 0.090 Naturalness × distance 1,11 1.391 3.215 0.10 Model df P1 N1 R2 MSE F p Power R2 MSE F p Power Contrast energy 1,94 0.002 1.56 0.17 0.69 0.07 3.0e-5 2.05 0.0028 0.96 0.05 Spatial coherence 1,94 0.002 1.56 0.20 0.65 0.07 0.0005 2.05 0.05 0.82 0.06 Naturalness rating 1,94 0.019 1.53 1.83 0.17 0.27 0.018 2.01 1.70 0.19 0.25 Contrast energy, spatial coherence 2,93 0.002 1.58 0.11 0.89 0.07 0.002 2.07 0.08 0.93 0.07 Contrast energy, naturalness 2,93 0.021 1.54 0.97 0.38 0.22 0.018 2.04 0.84 0.43 0.19 Spatial coherence, naturalness 2,93 0.028 1.54 1.24 0.29 0.27 0.018 2.04 0.84 0.43 0.19 Contrast energy, spatial coherence, naturalness rating 3,92 0.028 1.55 0.87 0.46 0.24 0.018 2.06 0.56 0.65 0.17 Fourier intercept 1,94 0.009 1.55 0.87 0.35 0.15 0.002 2.05 0.21 0.65 0.07 Fourier slope 1,94 0.017 1.54 1.67 0.19 0.25 0.001 2.05 0.10 0.75 0.06 Openness rating 1,94 0.008 1.54 0.78 0.38 0.15 0.010 2.03 0.99 0.32 0.17 Fourier intercept, fourier slope 2,93 0.019 1.54 0.92 0.40 0.21 0.003 2.07 0.12 0.89 0.08 Fourier intercept, openness rating 2,93 0.012 1.56 0.58 0.56 0.14 0.020 2.03 0.93 0.40 0.21 Fourier slope, openness rating 2,93 0.020 1.54 0.96 0.39 0.22 0.015 2.04 0.71 0.49 0.17 Fourier intercept, Fourier slope, openness rating 3,92 0.024 1.55 0.75 0.52 0.21 0.021 2.05 0.65 0.59 0.19 Contrast energy, spatial coherence, Fourier intercept, Fourier slope 4,91 0.032 1.56 0.75 0.56 0.25 0.005 2.11 0.11 0.98 0.07 Naturalness rating, openness rating 2,93 0.045 1.51 2.17 0.12 0.45 0.021 2.03 0.974 0.38 0.22 All combined 6,89 0.075 1.53 1.21 0.31 0.48 0.036 2.09 0.55 0.77 0.23 P2 Model df R2 MSE F p Power Contrast energy 1,94 0.124 2.16 13.35 0.0004 0.95 Spatial coherence 1,94 0.114 2.19 12.06 0.0008 0.93 Naturalness rating 1,94 0.092 2.24 9.49 0.003 0.86 Contrast energy, spatial coherence 2,93 0.138 2.15 7.43 0.001 0.93 Contrast energy, naturalness 2,93 0.226 1.93 13.61 6.5e-6 1.00 Spatial coherence, naturalness 2,93 0.166 2.08 9.25 0.0002 0.97 Contrast energy, spatial coherence, naturalness rating 3,92 0.227 1.95 8.99 2.7e-5 0.99 Fourier intercept 1,94 4.8e-4 2.47 0.045 0.83 0.06 Fourier slope 1,94 0.036 2.38 3.47 0.656 0.46 Openness rating 1,94 0.004 2.46 0.37 0.54 0.09 Fourier intercept, Fourier slope 2,93 0.191 2.02 10.99 5.1e-5 0.99 Fourier intercept, openness rating 2,93 0.007 2.48 0.31 0.73 0.10 Fourier slope, openness rating 2,93 0.036 2.41 1.72 0.19 0.37 Fourier intercept, Fourier slope, openness rating 3,92 0.207 2.00 7.98 8.1e-5 0.99 Contrast energy, spatial coherence, Fourier intercept, Fourier slope 4,91 0.208 2.10 5.99 0.0003 0.99 Naturalness rating, openness rating 2,93 0.096 2.26 4.94 0.009 1.00 All combined 6,89 0.366 1.65 8.58 2.3e-7 1.00
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