Self-objectification and eating disorders: the psychopathological and neural processes from psychological distortion to psychosomatic illness


 Self-objectification, characterized by treating oneself primarily as a physical entity (A body) or a collection of body parts, has been linked to the development of eating disorders. Yet, the precise mechanisms underpinning this link have remained elusive. From a psychopathological perspective, this article proposes that both self-objectification and eating disorders can be seen as manifestations of self-rumination (repetitive, negative self-focus). While self-objectification involves psychological rumination, eating disorders encompass a complex interplay of psychological and physical (bodily) rumination. In addition, at the neural level, the underlying neural foundations underlying such self-rumination are likely rooted in brain activity and connectivity within networks associated with self-reference, cognitive control, and body perception. Collectively, these perspectives shed light on the psychopathological and neural processes that links self-objectification to the onset of eating disorders.

Eating disorders are a kind of serious psychosomatic illness characterized by abnormal eating habits and thoughts regarding food and body weight (Tr easur e et al., 2020 ).They ar e highl y pr e v alent worldwide, particularly among adolescent girls and young adult w omen (Ar celus et al., 2011 ).For example, > 9% of the US population suffers from eating disorders, and 22.2-31.6% of c hildr en and adolescents are at risk of de v eloping eating disorders (He et al., 2017 ;Sparti et al., 2019 ).Around 5% of patients also experience symptoms of the illness throughout their entire lifetime, enduring long-term malnutrition and se v er e complications (Tr easur e et al., 2015 ), and > 10% of patients experience suicidal ideation or behavior (Conti et al., 2017 ).Thus, the identification of individuals at greater risk for de v eloping eating disorders and the proper implementation of early prevention and treatment strategies hold significant importance.
Eating disorders can arise due to a variety of factors, including the societal emphasis on physical a ppear ance (Ata et al., 2015 ).When an individual places excessive importance on their physical a ppear ance, it is r eferr ed to as self-objectification (Fr edric kson & Roberts, 1997 ).Self-objectification is a psychological issue, consistently accompanied by habitually monitoring and being dissatisfied with one's body (Ward et al., 2023 ;Zheng et al., 2015 ).It emphasizes physical a ppear ance ov er other attributes such as abilities, personality, and temperament, and includes e v aluating one's own a ppear ance fr om an external perspectiv e , o verlooking personal feelings and needs.Crucially, self-objectification has been linked to the presence of eating disorders, as demonstrated by correlational studies indicating that increased objectification of one's body is associated with ele v ated le v els of disorder ed eating attitudes and behaviors (Calogero, 2009 ;Dakanalis et al., 2015 ;Daubenmier, 2005 ;Geng, 2020 ;Guo et al., 2021 ;Han et al., 2019 ;Jongenelis et al., 2014 ;Kilpela et al., 2019 ;Lindner et al., 2012 ;Moradi & Huang, 2008 ;Niu et al., 2020 ;Rodgers & Melioli, 2016 ;Tiggemann & Williams, 2012 ;Yao et al., 2018 ;Zhao & Jiang, 2021 ;Zhang & Zeng, 2023 ).In one study that observed a correlation between self-objectification and eating disorders ( r = 0.39), a stronger effect was presented in women ( r = 0.41) than in men ( r = 0.20; Schaefer & T hompson, 2018 ).T he link was also more pronounced in white ( r = 0.42) and Asian American ( r = 0.42) women compared to African American or Black ( r = 0.34) women, and it was most robust among heterosexual women ( r = 0.39) while being weakest among heterosexual men ( r = 0.23; Nechita et al., 2021 ).
A significant proportion of individuals who experience selfobjectification may de v elop eating disorders, but ther e is still no consensus on the mec hanisms underl ying this relationship.In this r e vie w, we pr ovide a summary of psychological and neur oima ging r esearc h on the r elationship between selfobjectification and eating disorders, focusing on studies that have investigated the mechanisms involved in this link.First, we examine the psychopathological pathway of self-objectification. Second, we discuss the pathological mechanisms that connect selfobjectification to eating disorders .T hird, we discuss the neural mechanisms that underlie the connection.Finall y, we pr opose directions for future research.

T he psyc hopa thological pa thw ay of self-objectification
Self-objectification is a consequence of sexual objectification, whic h tr eats women as mer e bodies or collections of body parts (Bernard et al., 2020 ).Gener all y, women ar e exposed to sexual objectification stimuli (i.e.bare body, sexy pose, and appearance e v aluation) almost e v ery day via tele vision pr ogr ams, m usic videos , mo vies , WeChat Moments , Weibo Square , and other social media, as well as dail y inter personal inter actions .For example , it was r e v ealed on anal yzing 662 tele vision pr ogr ams that 96% of female actors were shown with their bodies exposed, but only 68% of male actors were shown wearing r e v ealing clothing (Flynn et al., 2015 ).In another instance, a multinational sample of women aged 18-46 years reported experiencing an average of 2.7 incidents of interpersonal sexual objectification over a 5-day period (Koval et al., 2019 ).
Following self-objectification, a series of psyc hologicall y pathological risks often ensue, particularly in relation to eating disorders.Specifically, self-objectification signals an imbalance in self-conce pt, leading to negati v e outcomes suc h as r educed internal sensiti vity, increased negati ve emotions, and impaired self-regulation (Ward et al., 2023 ).There is empirical evidence that individuals with self-objectification place an excessive emphasis on their a ppear ance, considering it m uc h mor e important than their competence (Vandenbosch et al., 2015 ).In addition, it has been shown that greater self-objectification is associated with less sensitivity to internal states (Ainley & Tsakiris, 2013 ), more negativ e emotions (suc h as shame, low self-esteem, anxiety; Dvir et al., 2021 ), and decr eased self-r egulation (Baker et al., 2017 ).For instance, individuals with greater self-objectification tended to feel less cold when wearing limited clothing outside a nightclub on a cold night (Felig et al., 2022 ), and they also performed more poorly on the Stroop test (Ching & Wu, 2022 ).A large number of studies have established a correlation between self-objectification and psychological issues, including depression and anxiety (Lindner & Tantleff-Dunn, 2017 ;Sun, 2021 ;Teng et al., 2019 ).
Self-objectification is essentially a form of rumination on the state of one's own body.That is, re petiti ve, prolonged, and recurr ent negativ e thinking about one's own body, a ppear ances, personal concerns and upsetting experiences.Earlier r esearc h has suggested that self-objectification may have more pronounced effects in individuals who are more inclined to ruminate in response to negative thoughts (Calogero & J ost, 2011 ).Furthermore , there is evidence that individuals experiencing self-objectification may become ensnared in ruminative thoughts about their own bodies, resulting in a decline in their overall sense of well-being (Jarrar, 2017 ).Taken together, self-objectification encompasses the concurr ent pr esence of both bod y and emotion, persistent negati ve thought patterns, and the r ecipr ocal r einforcement of negativ e emotions .T hese factors culminate in c hr onic depletion and regulatory dysfunction due to insufficient r esources, ultimatel y elevating the risk of developing disordered eating beha viors .

T he psyc hopa thological mec hanisms linking self-objectification and eating disorders
Early theory and research suggested that the link between selfobjectification and eating disorders was mediated by body shame (Caloger o, 2009 ;Fr edric kson & Roberts, 1997 ).Ho w e v er, a longitudinal model did not confirm this explanatory pathway (Kilpela e t al., 2019 ).Another hypothesis, known as the allocentric lock hypothesis, suggests that the pr ogr ession fr om self-objectification to eating disorders is related to the inability to update one's internalized body image with current sensory input through selfintegr ation (Riv a et al., 2015 ).Evidence has indicated that both individuals who self-objectifiers objectify and those with eating disor ders sho w lo w er memory performance compared to the contr ols (P acilli et al. , 2016 ;Serino et al. , 2015 ).
Here, we further suggest that self-rumination may bring out the relationship between self-objectification and eating disorders.Eating disorders are the result of self-criticism that is reinforced by rumination on negative body perceptions.Patients with eating disorders have a persistent negati ve bod y ima ge, whic h extends to a negative scheme for self-concept (Riva & Dakanalis, 2018 ).A meta-analysis of 38 studies revealed that rumination was significantly associated with eating disorders both concurr entl y ( r = 0.33) and pr ospectiv el y ( r = 0.23) and also that individuals with eating disorders exhibited greater levels of rumination compared to control participants (Smith et al., 2018 ).Mor eov er, in experimental studies that induced feelings of sadness or concerns related to eating or body image, and subsequently manipulated state rumination, it was noted that in women with eating disorders, rumination led to heightened negative mood, diminished body satisfaction, and increased analogue symptoms (e.g. the desire to binge or abstain) compared to conditions involving acceptance or distraction (Naumann et al., 2015(Naumann et al., , 2016 ) ).
Notabl y, the rumination observ ed in those with eating disorders is not limited to the psychological level (negative self-schemas); it is also present as behavioral rumination.This dual presence of rumination (psychological processes and behaviors) indicates that eating disorders are a disease that involves an interaction between the mind and the body.T hus , single physiological or psychological interv entions hav e limited effectiv eness in the tr eatment of eating disorders; as one example, medication, one of the most commonly used treatments, has shown limited effectiveness in addressing the psychological, somatic, or nutritional aspects of eating disorders (Blanchet et al., 2019 ).Despite receiving the most effective tr eatment (cognitiv e behavior al ther a py), > 60% of patients continue to display the core symptoms of eating disorders (Slade et al., 2018 ).On av er a ge, the effectiv eness of curr ent interv ention methods is moderate, with remission rates ranging from 40 to 60% in cases of anorexia nerv osa, bulimia nerv osa, and binge-eating disorder (Ed d y et al., 2017 ;Linardon, 2018 ).

T he neur al mec hanisms linking self-objectification and eating disorders
The brain activity in the self-referential network may indicate a tr ansition fr om self-objectification to eating disorders.Pr e vious neur oima ging r esearc h has demonstr ated the r ole of the selfr efer ential network in self-objectification (Cikara et al., 2011 ;Cogoni et al., 2018 ;Du et al., 2023 ), self-rumination (Int-Veen et al., 2023 ;Laicher et al., 2022 ;Rosenbaum et al., 2021 ), and eating disorders (Brooks et al., 2011 ;Martins et al., 2020 ;Spangler et al., 2012 ).Specifically, individuals with higher levels of self-objectification show decr eased br ain activity in the self-r efer ential network, including the medial frontal cortex, inferior frontal cortex, inferior parietal cortex, superior temporal cortex, and cingulate gyrus (Sun et al., 2016 ).Ho w e v er, it exhibits a distinct pattern during ruminativ e pr ocesses, as well as in individuals with eating disorders.One meta-analysis , in volving experimental tasks examining rumination from 14 fMRI studies with a total of 286 healthy participants, has confirmed the link between self-rumination and activation of the self-referential network (Zhou et al., 2020 ).This association is specifically attributed to the dorsal medial pr efr ontal cortex subsystem, which is believed to promote self-generated thoughts, whic h ar e based on internally constructed r epr esentations rather than external ones (Buckner & DiNicola, 2019 ).In eating disorders, individuals demonstrate increased activation in the self-r efer ential network compar ed to healthy controls when vie wing food ima ges (Br ooks et al., 2011 ), performing cognitiv e control tasks (Seitz et al., 2016 ), and evaluating body and self-images (Spangler et al., 2012 ).This activity of the self-r efer ential network could potentially signify the presence of negative thoughts and emotions concerning body ima ge, suc h as ruminativ e pr eoccupation with body shape and anxiety about gaining weight.
The connectivity within the self-r efer ential network might also contribute to the pr ogr ession fr om self-objectification to eating disorders.Within the self-r efer ential network, a cor e subsystem is present, comprising the medial prefrontal cortex, the posterior cingulate cortex, and the inferior parietal lobules .T his subsystem serves as the foundation for self-r ele v ant cognition, demonstr ating consistent enga gement acr oss mental states involving self-oriented processing (Delahoy et al., 2022 ).When individuals engaged in rumination, there were increased connec-tions between the core and the medial temporal lobe subsystem, while decreased connections between the core and the dorsal medial pr efr ontal cortex subsystem (Chen et al., 2020 ).Enhanced functional connectivity might signify immersion of oneself in the past, surr ounded by negativ e thoughts, while decr eased functional connectivity could be inter pr eted as a reduced focus on the pr esent.The alter ed connections within the self-r efer ential network are often associated with symptoms of eating disorders and other psychological illnesses (Chen et al., 2021 ).For instance, depression patients exhibited a more negative connectivity from the medial pr efr ontal cortex to the posterior cingulate cortex compared to healthy individuals, indicating an excessive regulation of the posterior cingulate cortex by the medial pr efr ontal cortex (Davey et al., 2017 ).In another example, participants with social anxiety disorder exhibited heightened excitatory connectivity from the posterior cingulate cortex to the medial prefrontal cortex and increased inhibitory connectivity from the inferior parietal lobule to the medial pr efr ontal cortex.These findings r eflect the c har acteristic fear of negative social evaluation experienced by individuals with social anxiety disorder (Jamieson et al., 2023 ).
Besides the self-r efer ential netw ork, the connectivity betw een the self-r efer ential, cognitiv e contr ol, and bod y perce ption networks plays a role in the progression from self-objectification to eating disorders.For instance, the stronger the connection between the self-r efer ential network and the somatosensory cortex, particularly in the secondary somatosensory cortex and ventr al pr emotor cortex, the gr eater the le v el of self-objectification (Du et al., 2023 ).These connections indicate a heightened focus on external attributes of self-related sensory information in selfobjectifiers, such as physical appearance.In eating disorders, the changes in connectivity between the self-referential, cognitive control, and body perception networks are found to be linked with mor e fr equent eating-disorder behaviors (Chen et al., 2021 ;Domakonda et al., 2019 ;Frank et al., 2021 ;Gaudio et al., 2016 ;Haynos et al., 2021 ).In one recent study, high body image concerns and bulimic behaviors were correlated with increased connections within the cognitive control network, as well as between the cognitiv e contr ol network, self-r efer ential network, and visual perception network, with decreased connections present between the r e w ar d sensitivity netw ork and visual per ception netw ork (Chen et al., 2023 ).This altered neural connectivity suggests the existence of some potential abnormal pathways underlying eating disorders, such as aberrant integration between information perception and r e w ar d v aluation, and excessiv e rumination on selfr efer ential thoughts about body image.Altogether, the activity and connectivity within and between the self-r efer ential, cognitiv e contr ol, and bod y perce ption networks could suggest a shift from self-objectification to the development of eating disorders.

Challenges and future directions
According to objectification theory (Fr edric kson & Roberts, 1997 ), the involvement of self-objectification in the development of eating disorders is str ongl y implicated, and numerous studies have been conducted to empiricall y inv estigate the relationship between these constructs.Still, there remain outstanding challenges to examining the pathological pathway leading from selfobjectification to the de v elopment of eating disorders, especiall y the underlying neural mechanisms.
First, scholars should broaden their research on the pathological c har acteristics and de v elopment of self-objectification by conducting longitudinal studies, as the use of cross-sectional data in pr e vious studies has limited their ability to definitiv el y iden-tify the mechanism of self-objectification (Schaefer & Thompson, 2018 ).T his ma y in volv e collecting online surv eys that e v aluate self-objectification, body surveillance, body shame, body dissatisfaction, and eating disorder pathology at the initial assessment, as well as 6-, 12-, and 24-month follow-ups.Second, since the self-r efer ential, cognitiv e contr ol, and body perception netw orks are no w kno wn to pla y a crucial role , research appr oac hes m ust e volv e accordingl y, especiall y within inv estigations aimed at examining the association between the changes in these networks and the pathological c har acteristics of selfobjectification, as well as the causal relationship with the de v elopment into eating disorders.Future studies could explore the particular neural networks that predict self-objectification characteristics, such as body surveillance, body shame, and body dissatisfaction, within the discovery sample of indi viduals.Ad ditionally, they might investigate the specific neural networks that predict symptomatology associated with eating disorders, such as body image concerns, binge eating, and compensatory behaviors, within a cohort of self-objectifiers.Third, future research should investigate the feasibility of using neurobiological alterations in the self-r efer ential network as diagnostic indicators for self-objectification, as well as a pr edictiv e indicator for the progr ession fr om self-objectification to eating disorders.Indeed, recent neur oima ging studies hav e attempted to identify pr edictors of risk factors across eating disorders, which offers a new direction for r esearc h (Chen et al., 2023 ).Futur e studies could use objectified material to initiate a state of self-objectification and to measure the activity of the self-referential network before and after priming.Fourth, it would be beneficial to use the brain activity and connectivity in the self-r efer ential, cognitiv e contr ol, and bod y perce ption networks as diagnostic and evaluative indicators for understanding the pathology and intervention effects of eating disorders.Future research could involve tracking a cohort of individuals experiencing self-objectification and analyzing both their brain activity and connectivity before and after the onset of eating disorder symptoms.Finall y, r ecent studies hav e described the important contributions of non-inv asiv e br ain stim ulation for the management of eating disorders (Duriez et al., 2020 ).By using tec hniques suc h as ma gnetic or electrical stim ulation, futur e studies have the potential to modify the pattern of brain activity and connectivity associated with eating disorders, while measuring eating disorder symptoms before and after the stimulation.
In conclusion, empirical neur oima ging studies ar e needed in the future to clarify how self-objectification contributes to the de v elopment and maintenance of eating disorders .T his knowledge could help inform pr e v ention and intervention strategies and guide the de v elopment of targeted treatments.
Centr al Univ ersities to Y.P., the Construction Pr oject of High-le v el Local Universities in Shanghai, and the Science Project at Shanghai Normal University.