Article Figures & Data
Figures
- Figure 1.
Experimental stimuli. Examples of each of the stimuli types used in the study (computer-generated human faces, photos of cars, and computer-generated spheres) are shown.
- Figure 2.
Functional MRI responses to approaching and withdrawing faces, cars, and spheres. The results of the analysis conducted using the DIPS (A) and PMv (B) anatomical ROIs are shown (n = 8). DIPS and PMv show a significant approach bias to faces, but not to cars or simple spheres. C, Lateral, medial, superior, and inferior views of cortical surface maps of activation to Approaching versus Withdrawing faces in the full cohort (n = 21) are shown. The outlines of the anatomically defined DIPS and PMv ROIs are shown in green, as well as the outlines of primary visual cortex (V1; defined as the region around the calcarine sulcus activated to all stimuli compared with fixation, at a height threshold of p < 0.05) and the FFA (defined as the region in the fusiform gyrus activated to all face stimuli compared with all car stimuli, at a height threshold of p < 0.05). These maps reveal that although DIPS and PMv show approached-biased responses, as well as a number of other regions, such as the PCC, precuneus, dorsal premotor cortex, and MT, lower-level visual areas, such as V1 and FFA, do not show this bias; Table 2, top. W, Withdrawal; A, Approach; R, right.
- Figure 3.
The approach bias to faces compared with the approach bias to cars. This figure shows the results of the analysis conducted using the following contrast: (Approaching − Withdrawing Faces) − (Approaching − Withdrawing Cars) in the full cohort (n = 21) in lateral, medial, superior, and inferior views of cortical surface maps. DIPS and PMv show a significantly greater approach bias to faces, compared with cars. The outlines of the anatomically defined DIPS and PMv ROIs are shown in green, as well as the outlines of V1 and the FFA; Table 2B. W, Withdrawal; A, Approach; R, right; C, approach-biased responses to the car stimuli; F, approach-biased responses to the face stimuli.
- Figure 4.
Functional connectivity of approach-biased DIPS and PMv. Clusters showing significant connectivity (p < 0.05; FDR corrected, cluster size threshold > 10 mm2) with the DIPS (A) and PMv (B) seed regions (which were constrained to voxels showing significant (p < 0.05) activation to the Approaching versus Withdrawing face stimuli) are displayed on inflated cortical surface maps (n = 17). Clusters showing positive correlations with the seed are shown in yellow-red, whereas those showing negative (anti-) correlations with the seed are shown in blue. In each panel, the seed is outlined in black, whereas the hypothesized target area for that seed (anatomically defined DIPS or PMv; see Materials and Methods) is outlined in green and labeled; Table 3. R, Right.
- Figure 5.
Specific DIPS-PMv functional connectivity network. A PMv seed was derived from the initial DIPS connectivity map (Fig. 4A) to isolate the portion of PMv with strong DIPS connectivity (see Materials and Methods). Displayed here is the connectivity map of this PMv seed (the region outlined in black and labeled PMv). Clusters of functionally coupled voxels were deemed significant if they met the following threshold: p < 0.05; FDR corrected, size >10 mm2. This analysis demonstrates that a ventral portion of the anatomically defined PMv ROI shows strong connectivity with DIPS. The portion of the DIPS ROI showing significant connectivity with this PMv seed is outlined in black and labeled DIPS. R, Right.
- Figure 6.
Correlations between DIPS-PMv functional connectivity and behavioral measures. A, Enlarged images of the relevant portions of the DIPS functional connectivity map (see Fig. 4A) are shown. An outline of the portion of PMv showing connectivity with DIPS is derived from this map and superimposed on the maps in C–F, to facilitate comparisons. Correlations between DIPS-PMv functional connectivity and behavior were examined by: (1) using predefined DIPS and PMv ROIs to extract the Pearson r values representing the degree of DIPS-PMv coupling in each individual (B) and (2) conducting voxelwise regression analyses using each behavioral measure as a regressor (C–F). B, A scatter plot shows the correlation between DIPS-PMv connectivity and personal space size. C–F, The scatter plots here are derived from the accompanying maps and displayed for illustration purposes only, to show each subject's contribution to the map to the left of each plot. The individual data were extracted using 3 mm radius spherical seeds centered around the two peak correlations in the corresponding map. A, Clusters showing a correlation (positive = yellow-red; negative = blue) with the resting-state activity of the DIPS seed are shown. C–F, Clusters of voxels which show a significant correlation (positive, yellow-red; negative, blue) between the behavioral measure (personal space size, personal space permeability, percentage of time spent with others, and percentage of time preferred with others) and the cluster's connectivity with DIPS are shown (n = 17). B, C, DIPS-PMv connectivity is negatively correlated with personal space size. D–F, DIPS-PMv connectivity is positively correlated with personal space permeability, the percentage of time spent with others and the preferred percentage of time spent with others, respectively; Table 4. R, Right; %, percentage.
- Figure 7.
Correlations between DIPS-default network functional connectivity and behavior. A, Medial views of the DIPS functional connectivity map (Fig. 4A) are shown for reference; clusters showing a significant correlation (positive, yellow-red; negative, blue) with the resting-state activity of the DIPS seed are shown. Tests for correlations between DIPS functional connectivity and behavior using voxelwise regression analyses revealed that, for regions with activity that was negatively (anti-) correlated with DIPS activity (i.e., default network regions), there were strong associations between the strength of these anti-correlations and the behavioral measures. B, C, Clusters of voxels showing a significant correlation (positive, yellow-red; negative, blue) between behavior (personal space size, B; personal space permeability, C) and that cluster's connectivity with DIPS are shown (n = 17). B, C, Functional coupling between DIPS and default network regions (including medial prefrontal cortex, mPFC, and PCC/precuneus/retrosplenial cortex) is positively correlated with personal space size (coordinates and p values for the voxel with the peak correlation: mPFC: −8, 37, 14; p = 2 × 10−6; PCC: 2, −51, 28; p = 1 × 10−5) and negatively correlated with personal space permeability (mPFC: 16, 41, 13; p = 3 × 10−6; PCC: −12, −41, 28; p = 3 × 10−4). Thus, weaker anticorrelations between DIPS and default regions (i.e., stronger connectivity) predicted larger personal space size and lower personal space permeability—a similar relationship to that found between DIPS-PMv functional connectivity and these behavioral measures (Fig. 6). R, right.
Tables
Subject Experimenter Personal space size (cm) Personal space permeability D1 D2 Male Male 58.6 ± 38.5 28.3 ± 21.9 58.4 ± 17.9% Female 53.6 ± 23.6 19.4 ± 12.3 68.9 ± 15.5% Female Male 68.2 ± 25.0 30.8 ± 13.5 55.6 ± 8.9% Female 52.0 ± 21.2 23.4 ± 11.9 55.7 ± 9.5% Average personal space sizes (Distance 1, D1) and personal space permeability (mean ± SD) of the male (n = 10) and female (n = 10) subjects in response to male and female experimenters as determined by the Stop Distance Paradigm (see Materials and Methods) are listed. Distance 2 (D2) is used to calculate the permeability of personal space.
Region BA Hemi Tal (x, y, z) Size (mm2) Z p A. Faces Approach versus Faces Withdrawal contrast Approach > Withdrawal Precuneus 7 R 11, −44, 51 291.1 5.6 3 × 10−8 7 L −8, −44, 54 155.5 4.8 2 × 10−6 Superior parietal gyrus (dorsal)a 7 L −19, −70, 40 553.7 5.3 1 × 10−7 7 R 10, −53, 57 397.8 5.2 2 × 10−7 7 R 25, −51, 52 191.2 4.3 2 × 10−5 7 R 35, −41, 57 80.4 4.3 2 × 10−5 7 L −17, −57, 59 60.5 4.3 2 × 10−5 7/2 R 30, −33, 44 14.6 3.9 1 × 10−4 7/5 L −34, −44, 56 87.1 3.9 1 × 10−4 7 L −12, −52, 56 20.0 3.7 2 × 10−4 7/5 L −22, −47, 57 15.6 3.7 2 × 10−4 7 L −23, −51, 61 17.0 3.6 3 × 10−4 Mid-cingulate gyrus 24 L −14, −17, 41 69.6 4.6 5 × 10−6 24 R 14, −13, 38 54.6 4.2 3 × 10−5 24 L −13, −16, 35 12.1 3.5 5 × 10−4 Precentral gyrus (dorsal); middle frontal gyrus 4 R 37, −4, 44 138.2 4.5 8 × 10−6 6 R 23, 5, 44 14.0 3.9 1 × 10−4 6 L −31, −1, 41 54.2 3.7 2 × 10−4 Superior parietal gyrus (ventral) 7 R 20, −73, 35 79.6 4.4 1 × 10−5 7 R 24, −69, 41 33.5 4.3 2 × 10−5 Precentral gyrus (ventral)b 6 L −51, −3, 27 35.9 4.0 7 × 10−5 6 L −55, −2, 35 48.7 3.7 2 × 10−4 6 R 52, −3, 29 108.6 3.7 2 × 10−4 Middle occipital gyrus, inferior temporal gyrus 18 L −30, −87, 15 50.8 4.0 7 × 10−5 37 R 45, −71, 7 64.8 4.0 7 × 10−5 19 R 40, −76, 20 13.3 3.7 2 × 10−4 37 L −40, −73, 4 23.2 3.7 2 × 10−4 Withdrawal > Approach Inferior parietal gyrus, supramarginal gyrus 40 R 45, −58, 42 46.6 3.7 2 × 10−4 B. Faces Approach − Withdrawal versus Cars Approach − Withdrawal contrast Superior parietal gyrus (dorsal)a 7 R 11, −53, 57 202.0 4.7 3 × 10−6 7 R 35, −41, 56 56.9 4.3 2 × 10−5 7 R 19, −58, 51 26.1 4.2 3 × 10−5 7 R 30, −33, 44 24.0 3.9 1 × 10−4 7 R 25, −51, 52 14.8 3.7 2 × 10−4 Precuneus 7 R 12, −44, 55 114.8 4.1 5 × 10−5 Superior frontal gyrus 6 R 22, 4, 44 10.9 4.0 7 × 10−5 Precentral gyrus (ventral)b 6 R 54, −1, 24 43.0 3.9 8 × 10−5 Precentral gyrus (dorsal), middle frontal gyrus 6 R 38, −4, 45 46.8 3.9 9 × 10−5 Superior parietal gyrus (ventral) 7 R 24, −69, 41 11.2 3.9 1 × 10−4 Middle, inferior temporal gyri 39 R 42, −64, 11 24.9 3.7 2 × 10−4 Postcentral gyrus 43 R 61, −11, 24 14.3 3.6 3 × 10−4 A, Clusters are listed which showed significantly (p < 0.05, FDR corrected, cluster size threshold >10 mm2) greater activation to Approaching versus Withdrawing face stimuli, as well as one cluster in the inferior parietal cortex showing greater activation to Withdrawing, compared with Approaching, faces (n = 21). B, Clusters are listed which showed a significantly greater approach bias (Approach > Withdrawal) to face compared to car stimuli (n = 21). No cluster showed a greater approach bias to cars compared with faces. Clusters falling within the predefined anatomical regions-of-interest (DIPS, PMv) are indicated with a and b (a, DIPS; b, PMv). Figs. 2, 3. Note that although the peak activations shown at the bottom are in the right hemisphere only, this is because the FDR threshold was higher for the left than for the right hemisphere (because of overall higher levels of activation in the right (vs the left hemisphere). At a non-FDR corrected threshold (p < 0.0005, cluster size >20 mm2), there is activation for this contrast in both the left (−18, −72, 43; z = 4.5; p = 7 × 10 −6; 88 mm2) and right (11, −53, 57; z = 4.7; p = 3 × 10 −6; 213 mm2) DIPS and left (−52, −3, 28; z = 4.4; p = 1 × 10−5; 97 mm2) and right (54, −1, 24; z = 3.9; p = 8 × 10−5; 47 mm2) PMv. BA, Brodmann area; Hemi, hemisphere; Tal, Talaraich coordinates of peak vertex; L, left; R, right.
Region BA Hemi Tal (x, y, z) Size (voxels) Z pc DIPS functional connectivity Positive correlations Superior parietal gyrus (dorsal) 7 L −24, −53, 63 23737 7.1 <1 × 10−4 Precentral gyrus (dorsal), middle frontal gyrus 4/6 R 34, −4, 46 1249 4.8 <1 × 10−4 4/6 L −30, −5, 46 880 4.7 1 × 10−4 Precentral gyrus (ventral) 6 L −51, 7, 25 617 4.7 1 × 10−4 6 R 51, 8, 11 994 4.1 5 × 10−4 Fusiform gyrus, cerebellum 37 R 26, −53, −12 397 4.4 2 × 10−4 Middle frontal gyrus 9 R 40, 42, 29 359 4.4 2 × 10−4 9 L −38, 40, 27 99 3.7 2 × 10−3 Cerebellum L −50, −50, −34 35 4.3 3 × 10−4 R 46, −50, −31 89 3.9 1 × 10−3 R 28, −73, −22 18 3.3 7 × 10−3 Pericalcarine, lingual gyri 17 R 2, −87, 6 45 3.5 4 × 10−3 17 R 2, −75, 9 64 3.0 2 × 10−2 Inferior frontal gyrus 45/46 R 40, 31, 6 51 3.3 6 × 10−3 45 L −32, 28, 12 35 3.2 9 × 10−3 Middle cingulate gyrus 24 0, 9, 29 25 3.1 1 × 10−2 Negative (anti-) correlations Hippocampus, parahippocampal gyrus 27 L −20, −22, −11 24934 5.7 9 × 10−4 Superior temporal gyrus 22 L −59, −48, 21 1570 5.2 1 × 10−3 39 R 55, −59, 23 935 4.3 2 × 10−3 Middle temporal gyrus 22 L −46, −12, −1 257 4.2 2 × 10−3 L −30, 9, −6 41 3.7 5 × 10−3 Middle frontal gyrus 6 R 20, 22, 58 119 3.9 4 × 10−3 8 L −40, 16, 49 273 3.7 5 × 10−3 Inferior frontal gyrus 45 L −50, 24, 12 57 3.3 1 × 10−2 45 R 57, 32, 9 13 2.9 2 × 10−2 Cerebellum R 57, −60, −27 11 3.3 1 × 10−2 L −10, −34, −20 16 3.1 2 × 10−2 Inferior temporal gyrus 20 L −63, −21, −23 13 3.0 2 × 10−2 PMv functional connectivity Positive correlations Precentral gyrus, middle frontal gyrus 6/4 L −51, −4, 32 36231 7.3 <1 × 10−4 Temporal pole 38 L −24, 12, −33 155 4.1 6 × 10−4 38 L −40, 20, −23 17 2.9 2 × 10−2 Inferior frontal gyrus 45 R 53, 35, 4 65 3.7 2 × 10−3 Middle cingulate gyrus 31 L −14, −18, 38 56 3.7 2 × 10−3 31/5 R 16, −26, 45 53 3.2 9 × 10−3 Caudate R 2, 10, 7 78 3.6 2 × 10−3 Middle temporal gyrus 21/37 L −51, −56, 6 117 3.6 3 × 10−3 37 R 51, −58, −2 54 3.3 6 × 10−3 Thalamus L −10, −19, 1 32 3.4 5 × 10−3 R 14, −20, 18 10 3.1 1 × 10−2 Superior temporal gyrus 36 R 16, 4, −29 103 3.4 5 × 10−3 Amygdala R 22, −1, −18 21 3.2 7 × 10−3 Superior parietal gyrus (dorsal) 7 L −18, −63, 60 57 3.2 8 × 10−3 Fusiform gyrus 37 L −44, −51, −11 11 3.0 1 × 10−2 Negative (anti-) correlations Precuneus, posterior cingulate gyrus 31 L −10, −59, 29 9338 5.3 3 × 10−3 Inferior parietal gyrus, angular gyrus 19/39 R 46, −70, 37 1959 4.7 3 × 10−3 Superior parietal gyrus 19/30 L −38, −70, 40 1192 4.6 3 × 10−3 Medial frontal gyrus 10 0, 58, 1 2352 4.5 3 × 10−3 Inferior temporal gyrus 37 L −63, −49, −14 885 4.5 3 × 10−3 20 R 65, −37, −10 42 3.6 9 × 10−3 Fusiform gyrus 20 R 46, −18, −18 476 4.4 3 × 10−3 Lingual gyrus, pericalcarine sulcus 18 R 4, −80, −1 300 4.3 3 × 10−3 17 L −28, −69, 13 13 3.4 1 × 10−2 Middle frontal gyrus 6 R 20, 20, 54 501 4.3 4 × 10−3 10 L −26, 60, −1 12 3.0 3 × 10−2 8 R 40, 16, 42 32 3.0 3 × 10−2 8 L −28, 11, 33 34 3.3 2 × 10−2 Caudate R 16, 9, 18 68 3.8 6 × 10−3 Putamen L −14, 2, −2 19 3.8 6 × 10−3 Thalamus L −24, −27, 5 28 3.8 6 × 10−3 Cerebellum L −20, −45, −47 44 3.7 7 × 10−3 R 26, −41, −38 10 3.6 1 × 10−2 L −24, −40, −30 24 3.1 2 × 10−2 R 51, −50, −27 15 3.1 2 × 10−2 L −34, −85, −24 14 3.0 3 × 10−2 Lateral orbitofrontal gyrus 11 R 38, 36, −17 115 3.7 7 × 10−3 Rostral anterior cingulate gyrus 32 L −16, 47, 3 24 3.3 2 × 10−2 Uncus 38 R 30, 9, −16 33 3.3 2 × 10−2 Medial orbitofrontal gyrus 10 0, 50, −16 47 3.3 2 × 10−2 Brain stem R 10, −31, −34 18 3.2 2 × 10−2 Parahippocampal gyrus 36 R 24, −17, −26 21 3.1 2 × 10−2 Superior frontal gyrus 9 L −22, 44, 35 11 2.8 4 × 10−2 Clusters showing significant connectivity (p < 0.05, FDR corrected; cluster size threshold >10 mm2) with the DIPS (top) and PMv (bottom) seed regions are listed (n = 17). BA, Brodmann area; Hemi, hemisphere; Tal, Talaraich coordinates of peak voxel; L, left; R, right.
Behavior BA Hemi Tal (x, y, z) Size (voxels) Z p Positive correlations Personal space permeability 4 R 48, 1, 17 168 3.6 2 × 10−4 4 L −48, 2, 7 100 3.2 8 × 10−4 6/44 L −46, 7, 24 12 2.8 3 × 10−3 Time spent with others 6/44 L −42, 7, 24 48 3.4 3 × 10−4 6 R 53, 4, 11 23 3.2 7 × 10−4 6/44 L −40, 8, 7 18 3.0 2 × 10−3 Time preferred with others 6/44 L −44, 7, 24 45 3.8 1 × 10−4 6 R 53, 4, 11 43 3.5 2 × 10−4 6/44 L −40, 8, 7 39 3.1 1 × 10−3 Negative correlations Personal space size (D1) 6/44 L −46, 7, 24 46 3.4 3 × 10−4 4 R 48, 1, 17 61 3.1 1 × 10−3 6 L −53, 2, 7 12 2.6 4 × 10−3 Results are shown of the voxelwise regression analyses of the DIPS functional connectivity data, using each behavioral measure as a regressor. Clusters of voxels within PMv showing a significant (p < 0.01, cluster size >10 mm2) correlation between the behavioral measure and their connectivity with DIPS are listed (n = 17); Fig. 6. BA, Brodmann area; Hemi, hemisphere; Tal, Talaraich coordinates of peak correlation.
In this issue
