Exp Brain Res (2015) 233:229–235 DOI 10.1007/s00221-014-4106-7
RESEARCH ARTICLE
Incidental self‑processing modulates the interaction of emotional valence and arousal Qianfeng Wang · Li Zheng · Lin Li · Xiao Xu · Xuemei Cheng · Ruipeng Ning · Zoltan Dienes · Xiuyan Guo
Received: 27 December 2013 / Accepted: 17 September 2014 / Published online: 30 September 2014 © Springer-Verlag Berlin Heidelberg 2014
Abstract The middle insula has been associated with incidental self-processing of negative information elicited by individual’s handwriting. However, emotional valence and arousal have been proved to work in an interactive way and located in middle insula. The present functional magnetic resonance imaging study used participant’s handwritings as material to explore how incidental self-processing affected the interaction of valence and arousal and its neural basis. Each participant was asked to read silently emotional and neutral words written by himself/herself or the other person. The right middle insula as well as the left putamen showed greater activations in response to emotional stimuli evoking conflicting approach-withdrawal tendencies (i.e.,
positive high-arousal and negative low-arousal words) relative to stimuli evoking congruent approach versus withdrawal tendencies (i.e., positive low-arousal and negative high-arousal words), whereas a reverse activation pattern in these two regions was observed during processing otherhandwriting. The current study indicated that incidental self-processing modulates the interaction of emotional valence and arousal. Keywords Incidental self-processing · Self-handwriting · Emotional valence and arousal · Insula
Introduction Q. Wang · X. Cheng · R. Ning (*) Shanghai Key Laboratory of Magnetic Resonance and Department of Physics, East China Normal University, North Zhongshan Road 3663, Shanghai 200062, China e-mail: [email protected] L. Zheng · L. Li · X. Xu School of Psychology and Cognitive Science, East China Normal University, North Zhongshan Road 3663, Shanghai 200062, China Z. Dienes School of Psychology, University of Sussex, Brighton, Falmer, Brighton BN1 9QH, UK X. Guo Shanghai Key Laboratory of Magnetic Resonance and School of Psychology and Cognitive Science, East China Normal University, Shanghai 200062, China X. Guo Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, East China Normal University, Shanghai 200062, China
Self is a unique psychological construct with a specific neural network. A large number of neuroimaging studies have demonstrated that the cortical midline structures (CMS), including anterior cingulate cortex (ACC), parietal/posterior cingulate cortex (PCC), as well as ventral and dorsal medial prefrontal cortex (vMPFC, dMPFC), are associated with intentional evaluations of self-referential stimuli (D’Argembeau et al. 2008; Doering et al. 2012; Fossati et al. 2003; Northoff et al. 2006; Moran et al. 2006, 2009; Musholt 2013; Northoff and Bermpohl 2004; Yaoi et al. 2009). In recent years, there has been an increase in neuroscience studies focusing on the self-processing of emotional stimuli. Several fMRI studies have investigated the neural mechanism underlying intentional self-processing of emotional information (Fossati et al. 2003; Moran et al. 2006; Yoshimura et al. 2009). Fossati et al. (2003) found that, in the self-referential condition, differences between the processing of positive and negative words were seen in the region of the middle insula. Moran et al. (2006) found that activity in the ventral ACC exhibited an interaction
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between self-relevance and emotional valence. Yoshimura et al. (2009) found the engagement of both the MPFC and the right amygdala during the intentional self-processing of emotional words. However, in many social contexts, incidental rather than intentional self-processing is more usual and automatic (Cloutier and Macrae 2008; Cunningham et al. 2008; Rameson et al. 2010; Turk et al. 2008). Thus, it is important to adopt tasks involving incidental self-processing to explore human self-processing of emotional information. Recently, using self-relevant materials and a non-self task, several neuroimaging studies have found that the CMS is engaged in incidental self-processing of neutral stimuli (Moran et al. 2009; Rameson et al. 2010) and the middle insula signaled incidental self-processing of negative stimuli (Zhu et al. 2013). Negative stimuli differed from neutral stimuli in both valence and arousal dimensions in the study of Zhu et al. (2013). Thus, we cannot draw any conclusion about the role of the insula in the different contributions of valence or arousal to the processing of emotion during incidental self-processing. It has been argued that valence and arousal affect the processing of emotional stimuli in an interactive way (Robinson et al. 2004). Positive low-arousal and negative higharousal stimuli are easier to process because they elicit congruent tendencies (approach or withdrawal, respectively), whereas positive high-arousal and negative low-arousal stimuli are more difficult to process because they elicit conflicting approach-withdrawal tendencies (Citron et al. 2014). Moreover, using fMRI, Citron et al. (2014) found more middle insula activity during the processing of emotional conflicting stimuli relative to emotional congruent stimuli, suggesting a key role of the middle insula in the interaction between emotional valence and arousal. However, the impact of specifically incidental self-processing on the interaction of emotional valence and arousal remains unclear. The present study aimed to investigate whether the interaction of emotional valence and arousal was modulated by incidental self-processing, and to investigate its underlying neural basis by adopting an eventrelated fMRI design. Handwriting was used as material in the present study, as self-handwriting is a common kind of self-relevant information in everyday life and has thus been shown useful for eliciting incidental self-processing (Ren and Feng 2001; Van Rooij and hazelzet 1997; Chen et al. 2008; Zhu et al. 2013). During the experiment, participants processed negative, neutral, and positive words written by themselves or others. A non-emotional task was used to rule out a ‘task-relevance’ effect. Based on the previous studies (Citron et al. 2014; Zhu et al. 2013), we predicted that middle insula activity moderated by an emotional valence by arousal interaction would be affected by incidental self-processing versus other processing.
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Exp Brain Res (2015) 233:229–235
Materials and methods Participants Sixteen right-handed volunteers (thirteen females, mean age = 21.4, SD = 2.9, range = 18–26) were recruited from the university community. All participants had normal or corrected-to-normal visual acuity, and none of them had any history of neurological or psychological disorder. All the participants were paid 50 RMB for their participation and gave informed consent before scanning. The study was approved by the Ethics Committee of the East China Normal University. Materials A total of 120 words selected from affective norms for English words (Bradley and Lang 1999) were used as material. All of these words were translated into 120 twocharacter Chinese nouns by two English experts. Then, these nouns were divided into two lists which were counterbalanced for the ratings of valence, arousal and dominance. Each list contained ten positive high-arousal (PH) words (e.g., ‘honor’), ten positive low-arousal (PL) words (e.g., ‘freedom’), ten negative high-arousal (NH) words (e.g.,‘tumor’), ten negative low-arousal (NL) words (e.g., ‘hell’), and 20 neutral words (e.g., ‘truck’) used to introduce a baseline condition. To ensure our manipulation of valence were valid, a 2 (valence: negative vs. positive) × 2 (arousal: high vs. low) × 2 (self-processing: self vs. other) repeated measures ANOVA on valence ratings was conducted. Results revealed only a significant main effect of valence [F(1, 9) = 1,972.49, p
RESEARCH ARTICLE
Incidental self‑processing modulates the interaction of emotional valence and arousal Qianfeng Wang · Li Zheng · Lin Li · Xiao Xu · Xuemei Cheng · Ruipeng Ning · Zoltan Dienes · Xiuyan Guo
Received: 27 December 2013 / Accepted: 17 September 2014 / Published online: 30 September 2014 © Springer-Verlag Berlin Heidelberg 2014
Abstract The middle insula has been associated with incidental self-processing of negative information elicited by individual’s handwriting. However, emotional valence and arousal have been proved to work in an interactive way and located in middle insula. The present functional magnetic resonance imaging study used participant’s handwritings as material to explore how incidental self-processing affected the interaction of valence and arousal and its neural basis. Each participant was asked to read silently emotional and neutral words written by himself/herself or the other person. The right middle insula as well as the left putamen showed greater activations in response to emotional stimuli evoking conflicting approach-withdrawal tendencies (i.e.,
positive high-arousal and negative low-arousal words) relative to stimuli evoking congruent approach versus withdrawal tendencies (i.e., positive low-arousal and negative high-arousal words), whereas a reverse activation pattern in these two regions was observed during processing otherhandwriting. The current study indicated that incidental self-processing modulates the interaction of emotional valence and arousal. Keywords Incidental self-processing · Self-handwriting · Emotional valence and arousal · Insula
Introduction Q. Wang · X. Cheng · R. Ning (*) Shanghai Key Laboratory of Magnetic Resonance and Department of Physics, East China Normal University, North Zhongshan Road 3663, Shanghai 200062, China e-mail: [email protected] L. Zheng · L. Li · X. Xu School of Psychology and Cognitive Science, East China Normal University, North Zhongshan Road 3663, Shanghai 200062, China Z. Dienes School of Psychology, University of Sussex, Brighton, Falmer, Brighton BN1 9QH, UK X. Guo Shanghai Key Laboratory of Magnetic Resonance and School of Psychology and Cognitive Science, East China Normal University, Shanghai 200062, China X. Guo Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, East China Normal University, Shanghai 200062, China
Self is a unique psychological construct with a specific neural network. A large number of neuroimaging studies have demonstrated that the cortical midline structures (CMS), including anterior cingulate cortex (ACC), parietal/posterior cingulate cortex (PCC), as well as ventral and dorsal medial prefrontal cortex (vMPFC, dMPFC), are associated with intentional evaluations of self-referential stimuli (D’Argembeau et al. 2008; Doering et al. 2012; Fossati et al. 2003; Northoff et al. 2006; Moran et al. 2006, 2009; Musholt 2013; Northoff and Bermpohl 2004; Yaoi et al. 2009). In recent years, there has been an increase in neuroscience studies focusing on the self-processing of emotional stimuli. Several fMRI studies have investigated the neural mechanism underlying intentional self-processing of emotional information (Fossati et al. 2003; Moran et al. 2006; Yoshimura et al. 2009). Fossati et al. (2003) found that, in the self-referential condition, differences between the processing of positive and negative words were seen in the region of the middle insula. Moran et al. (2006) found that activity in the ventral ACC exhibited an interaction
13
230
between self-relevance and emotional valence. Yoshimura et al. (2009) found the engagement of both the MPFC and the right amygdala during the intentional self-processing of emotional words. However, in many social contexts, incidental rather than intentional self-processing is more usual and automatic (Cloutier and Macrae 2008; Cunningham et al. 2008; Rameson et al. 2010; Turk et al. 2008). Thus, it is important to adopt tasks involving incidental self-processing to explore human self-processing of emotional information. Recently, using self-relevant materials and a non-self task, several neuroimaging studies have found that the CMS is engaged in incidental self-processing of neutral stimuli (Moran et al. 2009; Rameson et al. 2010) and the middle insula signaled incidental self-processing of negative stimuli (Zhu et al. 2013). Negative stimuli differed from neutral stimuli in both valence and arousal dimensions in the study of Zhu et al. (2013). Thus, we cannot draw any conclusion about the role of the insula in the different contributions of valence or arousal to the processing of emotion during incidental self-processing. It has been argued that valence and arousal affect the processing of emotional stimuli in an interactive way (Robinson et al. 2004). Positive low-arousal and negative higharousal stimuli are easier to process because they elicit congruent tendencies (approach or withdrawal, respectively), whereas positive high-arousal and negative low-arousal stimuli are more difficult to process because they elicit conflicting approach-withdrawal tendencies (Citron et al. 2014). Moreover, using fMRI, Citron et al. (2014) found more middle insula activity during the processing of emotional conflicting stimuli relative to emotional congruent stimuli, suggesting a key role of the middle insula in the interaction between emotional valence and arousal. However, the impact of specifically incidental self-processing on the interaction of emotional valence and arousal remains unclear. The present study aimed to investigate whether the interaction of emotional valence and arousal was modulated by incidental self-processing, and to investigate its underlying neural basis by adopting an eventrelated fMRI design. Handwriting was used as material in the present study, as self-handwriting is a common kind of self-relevant information in everyday life and has thus been shown useful for eliciting incidental self-processing (Ren and Feng 2001; Van Rooij and hazelzet 1997; Chen et al. 2008; Zhu et al. 2013). During the experiment, participants processed negative, neutral, and positive words written by themselves or others. A non-emotional task was used to rule out a ‘task-relevance’ effect. Based on the previous studies (Citron et al. 2014; Zhu et al. 2013), we predicted that middle insula activity moderated by an emotional valence by arousal interaction would be affected by incidental self-processing versus other processing.
13
Exp Brain Res (2015) 233:229–235
Materials and methods Participants Sixteen right-handed volunteers (thirteen females, mean age = 21.4, SD = 2.9, range = 18–26) were recruited from the university community. All participants had normal or corrected-to-normal visual acuity, and none of them had any history of neurological or psychological disorder. All the participants were paid 50 RMB for their participation and gave informed consent before scanning. The study was approved by the Ethics Committee of the East China Normal University. Materials A total of 120 words selected from affective norms for English words (Bradley and Lang 1999) were used as material. All of these words were translated into 120 twocharacter Chinese nouns by two English experts. Then, these nouns were divided into two lists which were counterbalanced for the ratings of valence, arousal and dominance. Each list contained ten positive high-arousal (PH) words (e.g., ‘honor’), ten positive low-arousal (PL) words (e.g., ‘freedom’), ten negative high-arousal (NH) words (e.g.,‘tumor’), ten negative low-arousal (NL) words (e.g., ‘hell’), and 20 neutral words (e.g., ‘truck’) used to introduce a baseline condition. To ensure our manipulation of valence were valid, a 2 (valence: negative vs. positive) × 2 (arousal: high vs. low) × 2 (self-processing: self vs. other) repeated measures ANOVA on valence ratings was conducted. Results revealed only a significant main effect of valence [F(1, 9) = 1,972.49, p
