خروج از عشق مربوط به پردازش جامع از چهره های با ابراز هیجانی و بازخورد احساسی ناهمخوان است: شواهدی از ERPs

Abstract Parental use of love withdrawal is thought to affect children's later psychological functioning because it creates a link between children's performance and relational consequences. To investigate whether love withdrawal is also associated with the underlying level of basic information processing in the brain, we studied event-related potentials to feedback stimuli that combined performance feedback with emotional facial expressions. We focused on the VPP (face processing) and N400 (incongruence processing). More maternal use of love withdrawal was related to more positive VPP amplitudes, larger effects of the emotional facial expression on VPP amplitude, and more negative N400 responses to incongruent combinations of feedback and facial expressions. Our findings suggest a heightened processing of faces with emotional expressions and greater sensitivity to incongruence between feedback and facial expression in individuals who experienced more love withdrawal.

. Results 2.1. Behavioral data The average error rate for our participants was 16% (SD = 7). Participants responded significantly faster to congruent (M = 263 ms, SD = 31) than to incongruent targets (M = 307 ms, SD = 41), t(26) = −13.37, p < .01. Maternal use of love withdrawal (LWm) and fear of failure (FoF) were significantly correlated (r = .47, p < .05). LWm and FoF were not significantly correlated with participants’ error percentages and reaction times to congruent and incongruent targets (all rs < |.25|, all ps > .10). 2.2. ERPs: preliminary analyses Because, as mentioned above, VPP amplitude appeared to be more positive in response to disgusted compared to happy faces, we performed an ANOVA with color (red vs. green) and facial expression (happy vs. disgusted) as the independent variables. We found a significant main effect of facial expression, F(1, 26) = 9.97, p < .05, confirming our observation. There was a significant main effect of color as well (more positive VPP in response to green compared to red photographs), F(1, 26) = 14.52, p < .05, but no significant interaction of color and facial expression, F(1, 26) = 1.77, p > .10. To confirm the occurrence of N400 responses to incongruent facial expressions, an ANOVA was performed with color (red vs. green) and congruence (congruent vs. incongruent) as independent variables and the average amplitude across the time range (i.e., 300–450 ms) and electrodes (i.e., 80, 86, 87 [CP2], 93 [CP4] and 105) chosen for analysis of the N400 as the dependent variable. We found a significant main effect of congruence, F(1, 26) = 8.98, p < .05, confirming the presence of the N400. The main effect of color was significant as well, F(1, 26) = 35.70, p < .05 (more positive amplitude in response to green compared to red photographs), but there was no significant interaction of color and congruence, F(1, 26) = 0.03, p > .10. 2.3. ERPs: analyses with LWm and FoF Grandaverage ERPs at Cz and CP4 time-locked to the onset of the feedback stimuli are presented in Fig. 1 and Fig. 2, illustrating the VPP and N400. Fig. 3 presents scalp voltage-distributions for these two components. Grandaverage ERPs at Cz, illustrating the VPP. A and B: ERPs to green (A) and ... Fig. 1. Grandaverage ERPs at Cz, illustrating the VPP. A and B: ERPs to green (A) and red (B) feedback stimuli (i.e., feedback following correct and incorrect responses) for participants reporting low maternal use of love withdrawal. C and D: ERPs to green (C) and red (D) feedback stimuli for participants reporting high maternal use of love withdrawal. Participants were divided into groups for displaying purposes only. Participants reporting higher maternal use of love withdrawal showed a more positive response to the feedback stimuli between 140 and 180 ms after stimulus onset (VPP) and a larger difference in VPP amplitude to happy and disgusted facial expressions (more positive VPP to disgusted than to happy expressions). ERPs were low-pass filtered at 15 Hz for displaying purposes. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of the article.) Figure options Grandaverage ERPs at CP4, illustrating the N400. (A) ERPs to congruent and ... Fig. 2. Grandaverage ERPs at CP4, illustrating the N400. (A) ERPs to congruent and incongruent feedback stimuli for participants reporting low maternal use of love withdrawal. (B) ERPs to congruent and incongruent feedback stimuli for participants reporting high maternal use of love withdrawal. Participants were divided into groups for displaying purposes only. Participants reporting higher maternal use of love withdrawal showed a more negative response to incongruent compared to congruent feedback stimuli between 300 and 450 ms after stimulus onset at right parietal electrode sites (N400). ERPs were low-pass filtered at 15 Hz for displaying purposes. Figure options Scalp voltage distributions of VPP and N400. VPP: voltage distribution of the ... Fig. 3. Scalp voltage distributions of VPP and N400. VPP: voltage distribution of the ERP (averaged over all feedback stimuli) across the 140–180 ms post-stimulus interval. N400: voltage distribution of the incongruent–congruent difference wave across the 348–400 ms post-stimulus interval. The maximum of the VPP is marked with ‘+’, the minimum of the N400 with ‘−’. Figure options All analyses described below were first conducted with order of administration (placebo first vs. oxytocin first) and use of oral contraceptives (used vs. not used) as additional independent variables. Because no significant effects for order of administration (all Fs < 2.53, all ps > .10) and use of oral contraceptives (all Fs < 2.03, all ps > .10) were found, we excluded these variables from the final analyses. We performed a repeated measures ANCOVA with VPP amplitude as the dependent variable, color (red vs. green) and facial expression (happy vs. disgusted) as within subjects factors, and LWm and FoF as covariates. We obtained a significant main effect of LWm, F(1, 24) = 7.05, p < .05, and a significant interaction effect between facial expression and LWm, F(1, 24) = 12.61, p < .01. Higher maternal use of love withdrawal was associated with more positive VPP amplitudes in response to the feedback stimuli and with larger effects of facial expression (more positive VPP to disgusted than to happy faces) on VPP amplitude. Fig. 1 presents grandaverage ERPs at Cz to illustrate these effects. No significant main effects of color, facial expression and fear of failure were found, and none of the other interaction effects was significant (all Fs < 2.88, all ps > .10). Next, we performed a repeated measures ANCOVA with N400 amplitude as the dependent variable, color (red vs. green) as within subjects factor, and LWm and FoF as covariates. The main effect of LWm was significant, F(1, 24) = 7.35, p < .05. Higher maternal use of love withdrawal was associated with a more negative N400 (i.e., more negative voltage to incongruent compared to congruent feedback). No significant main effects of color and FoF were found, and none of the interaction effects were significant (all Fs < 2.47, all ps > .10). Fig. 2 presents grandaverage ERPs at CP4 time-locked to the onset of congruent and incongruent feedback stimuli, and the incongruent–congruent difference wave, illustrating the main effect of maternal use of love withdrawal. Because no significant effects of FoF were found in any of the analyses described above, we repeated the analyses with fear of failure as the only covariate (i.e., excluding LWm from the analyses). No significant main effects of or interactions involving FoF were found (all Fs < 1.10, all ps > .10).