Battered Body, Battered Self: A Cross-Sectional Study of the Embodiment-Related Impairments of Female Victims of Intimate Partner Violence

ABSTRACT Intimate-partner violence (IPV) is a major threat to women’s lives, with an impact on their physical and mental health, often causing trauma symptoms. The IPV consequences for embodiment-related features that are detrimental to the quality of life and identity structure of victims are understudied. With this study, we aim to examine embodiment-related functions and physical and mental health of women with and without a history of IPV. A total of 47 female victims of IPV (mean age 41.3 ± 11.5 years) living in shelters and 44 non-victims (mean age 43.1 ± 12.5 years) living in the community participated in this cross-sectional study. We used a self-administered survey to assess the prevalence of mental health symptoms, somatic symptoms, and behaviors of self-injury and suicidal ideation. The levels of interoception, movement imagery, body ownership, and bodily dissociation were assessed through tasks and questionnaires, controlling for mental health covariates. Women victims of IPV showed a greater prevalence of posttraumatic stress disorder (p = .014), depression (p < .001), somatic symptoms (p = .006), self-injury behaviors (p < .001), and suicidal ideation (p < .001). Also, IPV victims showed higher levels of body disownership (p = .025) and bodily dissociation (p < .001) than non-victims, controlling for the presence of PTSD and depression. Our study shows strong evidence of the link between IPV and impairments in embodiment, namely the sense of body ownership and the disconnection from the body. Intimate-partner violence victims need embodiment-informed care to be parallel to the attention given to mental health and somatic symptoms.

Intimate partner violence (IPV) is a major threat to women's life and health, which can be even more significant in times of crisis.Indeed, during the worldwide lockdown due to the COVID-19 pandemic, there was an overall increase of IPV incidents (Piquero et al., 2021).Several mental health problems like post-traumatic stress disorder (PTSD), anxiety, depression, and alexithymia are frequently reported by female victims of IPV, as well as other health-related issues, such as limited mobility, eating and sleeping disorders, pain syndromes, substance abuse, self-injury, and suicidal ideation (World Health Organization (WHO), 2021).
The impact of violence can reach beyond the physical and mental health, affecting embodiment features (e.g., interoception, motor imagery, body ownership, bodily dissociation) that are detrimental for the quality of life, functionality, and identity of women victims of IPV (Dillon et al., 2013;Edelman, 2005;Machorrinho et al., 2019;Machorrinho, Veiga, Santos, Marmeleira et al., 2021b;Marmeleira & Santos, 2019).Repeated violence triggers several defensive responses of social engagement (e.g., call out for help), mobilization (fight/flight) or immobilization (Levine et al., 2018).When continuously maintained, the defensive responses of mobilization or immobilization become maladaptive, causing trauma symptomatology (Payne et al., 2015;Van der Kolk, 2015).Payne et al. (2015) proposed that a dysregulation of the autonomic, limbic, motor and arousal systems, namely the Core Response Network, perpetuate those defensive responses and negatively impacts interoception, proprioception, imagery, and affective regulation.
Other than violence, there are other factors that can impact embodimentrelated functions.For example, people vulnerable to suicide attempts seem to better tolerate situations that cause physical harm and/or threaten life, through decreased interoceptive awareness (Smith et al., 2018), or by using selfregulation strategies less based on bodily sensations (Paulus et al., 2019).Also, individuals with eating disorders and substance use, show a dysregulated (either enhanced or impaired) insular processing of interoceptive cardiac sensations (Köteles, 2021).In anxiety and trauma-related disorders, the sense of body ownership (highly studied as a measure of embodiment (Longo et al., 2008)) has been found to be somehow altered (Ehrsson et al., 2007;Macpherson et al., 2021;Rabellino et al., 2016).
A recent study showed a high prevalence of PTSD, anxiety, and depression among female victims of IPV, along with significant symptoms of bodily dissociation and difficulties in trusting the internal sensations of the body (Machorrinho, Veiga, Santos, Marmeleira et al., 2021a).Among that group of women, somatic symptoms were the most reported on questionnaires assessing PTSD and anxiety.However, in the study of (Machorrinho, Veiga, Santos, Marmeleira et al., 2021a), embodiment and mental health variables of women victims of IPV were not compared with women not exposed to IPV.The aim of the present study was to compare embodiment-related measures and mental health of women with and without history of IPV.Based on Machorrinho, Veiga, Santos, Marmeleira et al. (2021a), we hypothesized that women with past IPV experiences might have (1) weakened embodiment-related abilities, and (2) greater prevalence of PTSD, anxiety, depression, and substance use behaviors, self-injury and suicidal ideation.

Method
This study uses part of the data from a cross-sectional study with female victims of IPV living in Portuguese shelters, between January 2020 and November 2021.

Procedures and sample
Based on the (European Union Agency for Fundamental Rights, 2014) report, almost 20% of Portuguese women have suffered some kind of IPV.Of those, 2877 women have lived in a Portuguese victims' shelter during 2021 (Comissão para a cidadania e igualdade de género, 2021).This study used a case-control design, with the aim of comparing women who had experienced IPV and women who had never experienced IPV.OpenEpi was used to calculate the minimum required sample size for unmatched case-control studies (Sullivan et al., 2009).For this calculation, significance level (alpha) was set at .05, power at 90%, proportion of controls with exposure at 20%, ratio of sample size at 1, and hypothetical proportion of cases with exposure at 80% (Moreira et al., 2019).Results indicated that a minimum of 15 cases and 15 controls were required.
For the IPV group, the study was presented to four shelters for female victims of IPV, from the region of Alentejo, Portugal.After approval from their managing entities, female victims were asked to participate, and a total of 47 accepted to enroll in the study (92% of acceptance).For the no-IPV group, a presentation of the study and an invitation to participate was disseminated through social media, through personal relationships, and at the university facilities.With the purpose of not biasing the interest to participate, the study was described as assessing embodiment-related variables in adult women, with no reference to IPV.The no-IPV inclusion criteria were only explained in the first contact with the participants, and women who have suffered any type of IPV were included in another study (Machorrinho et al., 2021b).Of the 53 women from the local community who showed interest in participating, 44 women without a history of IPV were included in the study.
The invitation to participate had as inclusion criteria a) being female, b) aged ≥18 years.Confidentiality was maintained and participation was subject to informed consent.Assessments took about 60 minutes with each participant and were performed individually in a quiet room of the shelter -for the IPV group -or at university facilities or participants' home -for the no-IPV group.After a brief explanation of the purpose of the study, participants filled out a sociodemographic survey (assessing social variables, general health symptoms and past behaviors of substance use, self-injury, and suicidal ideation).Mental health and embodiment-related functions (levels of interoception, movement imagery, body ownership, and bodily dissociation) were assessed through tasks and questionnaires.
The study was approved by the University ethics committee and conducted in accordance with the Declaration of Helsinki (General Assembly of the World Medical Association, 2014).

Measures
Motor imagery was evaluated by the Movement Imagery Questionnaire-3 (MIQ-3, Williams et al., 2012).The MIQ-3 evaluates kinesthetic, visual internal and visual external modalities in adults.After performing each of the four simple movements (i.e., lifting the right leg, abduction of the non-dominant arm, jump and bend over), participants were asked to use a 7-point Likert scale to rate the ease or difficulty of seeing and feeling the movements, without moving (Mendes et al., 2016).The Portuguese adaptation showed acceptable validity and reliability properties (Cronbach's alpha = 0.88; Mendes et al., 2016).
Interoception is the sensing, interpretation and regulation of the internal visceral signs of the body (Chen et al., 2021;Craig, 2003).It was evaluated in two dimensions: interoceptive accuracy (objective accuracy detecting internal signals of the body), and interoceptive sensibility (dispositional tendency to focus internally into the sensations of the body; Garfinkel & Critchley, 2013).
To assess the interoceptive accuracy, we administered the Heartbeat Counting Task (HCT, Schandry, 1981).In a sitting position, participants were asked to count the heartbeats felted during each trial of 45, 35, 55, and 25 seconds, presented in a fixed order.A pulse oximeter was fitted on their index finger of the left hand for physiological heartbeat detection.For each trial, an accuracy score was derived: 1− (real beats− reported beats)/((real beats + reported beats)/2).Resulting accuracy scores were averaged over the 4 trials, yielding an average value for each participant.
Interoceptive sensibility was assessed through the Portuguese version of the self-report questionnaire Multidimensional Assessment of Interoceptive Awareness (Machorrinho et al., 2018).MAIA's Portuguese version comprises 33 items, and through a 6-point Likert scale (0: never; 5: always) where higher scores represent more positive interoceptive sensibility, assesses 7 dimensions: Noting (i.e., awareness of body sensations), Not-distracting (i.e., tendency not to distract oneself from sensations of pain or discomfort), Not-worrying (i.e., tendency not to worry with sensations of pain or discomfort), Attention Regulation (ability to sustain and control attention), Emotional Awareness (i.e., awareness of the connection between body sensations and emotional states), Self-regulation (i.e., ability to regulate distress by attention to body sensations), and Trusting (i.e., experience of one's body as safe and trustworthy; Machorrinho et al., 2018;Mehling et al., 2012).The MAIA's Portuguese version shows good psychometric properties (Cronbach's alphas ranging from 0.61 to 0.87 across the scales, and test-retest reliability ranging from 0.52 to 0.83; Machorrinho et al., 2018).
For assessing Body Ownership (the feeling of my body as my own), the Rubber Hand Illusion was administered following the protocol from Rabellino et al. (2016).Participants sat across from the experimenter with their arms resting on a table.With their right hand inside of a specially constructed black box, each of the fingers of the participant's real hand, and of the rubber hand, were synchronously brushed for 2 min, with two identical soft paintbrushes.After the experiment, participants were asked to complete a nine-item questionnaire that assessed their subjective experience (translated from Rabellino's study (2016) by three independent researchers).
Bodily Dissociation (the sense of separation from the body) was assessed through the Scale of Body Connection (SBC; Price & Thompson, 2007), a selfreport Likert scale that measures Body Awareness and Bodily Dissociation.The adaptation from Neves et al. (2017) confirmed the reliability and validity of this scale for the Portuguese population (Cronbach's alpha = 0.73).
Posttraumatic Stress Disorder symptoms in the last 2 months were evaluated through the PTSD Checklist -civilian version (PCL; Weathers et al., 1993).This self-report questionnaire is able to differentiate the three PTSD clusters from DSM-IV medical diagnostic manual: Reexperiencing, Avoiding and Hyper-vigilance.Following Barreiras (2015), we have considered as clinically relevant levels of PTSD, having at least one symptom of the reexperiencing cluster, three of the avoiding and 2 of the hyper-vigilance cluster.The Portuguese version includes 17 items and has showed good psychometric properties (Cronbach's alpha = 0.94; Marcelino & Gonçalves, 2012).
Hospital Anxiety and Depression Scale (HADS; Zigmond & Snaith, 1983) enables health professionals to assess anxiety and depression levels at a brief and objective way (Herrmann, 1997).It is a self-report questionnaire with 14 items, seven assessing anxiety and seven assessing depression symptoms.Each item is rated in a 0-3 scale and classifies the symptom has feeling equal to times before or a lot worse than before.Scores higher than 7 in each subscale, indicate clinically relevant levels of anxiety or depression.The Portuguese version has good internal consistency (Cronbach's alpha_anxiety scale = 0.76; Cronbach's alpha_depression scale = 0.81; McIntyre et al., 1999).

Data analysis
Descriptive statistics of socio-demographic data, health symptoms, health behavior, and embodiment-related variables were performed for both IPV and no-IPV groups.Shapiro-Wilk test was used to check data normality.
A comparison of both groups' mental health and embodiment-related variables was performed by means of the Chi-square test for categorical variables, the independent sample t-test for parametric variables, or the corresponding non-parametric Mann-Whitney test.Based on previous studies that found associations between some embodiment-related variables and symptoms of PTSD, anxiety, and depression, in this study, the embodiment variables that were statistically different between groups were then analyzed through oneway analysis of covariance (ANCOVAs; 95% confidence interval), controlling for the presence of PTSD, anxiety, and depression diagnoses.Statistical analyses were performed with SPSS (Statistical Package for the Social Sciences), version 24.0.

Results
A total of 91 women participated in this study.Table 1 presents the sociodemographic characteristics of both IPV and no-IPV groups.The majority of IPV victims had a secondary educational level or less, whereas most of the non-victims had an educational level above the secondary level (p = .001).When compared to non-victims, IPV victims showed significantly higher Body Mass Indices (BMI) (p < .01),along with an increased frequency of smoking behaviors (p = .008),sleep problems (p = .002),respiratory problems (p = .010),anxiety attacks (p = .006),migraines (p = .004),and medical Of the 47 participants of the IPV group, only 37 were able to perform de MIQ tasks, due to difficulty in understanding the mental tasks, or due to physical impairments that enabled them to perform the movements.
Table 2 presents the between-groups analysis of the embodiment-related variables.Results showed that IPV victims (Mdn = 2.667; range −3.0-3.0)experienced a stronger sensation of ownership of the rubber hand than the non-victims (Mdn = 0.667; range −3.0-3.0)(U = 724; p = .025),which translates into a weaker sense of body ownership.Bodily dissociation levels of both groups were also different (U = 467; p < .001),with IPV victims (Mdn = 2.75; range 1.3-4.8)showing significantly higher scores than nonvictims (Mdn = 1.88; range 1.0-3.5).After controlling for the diagnosis of PTSD and depression, ANCOVA results showed that there was still a significant difference in body ownership [F(1,87) = 8.508, p = .005]and bodily dissociation between groups.

Discussion
We examined health and embodiment-related variables of women with and without a history of intimate-partner violence.To the best of our knowledge, this is the first study to examine the differences between women victims and non-victims of IPV regarding embodiment-related variables such as interoception, movement imagery, body ownership, and bodily dissociation.Female victims of IPV showed higher values of bodily dissociation, along with a weaker sense of body ownership, representing an overall weaker sense of embodiment, compared to women who have never been victims of IPV.Despite the efforts to recruit participants with similar sociodemographic characteristics for both groups, victims of IPV reported having a lower educational status, and more physical and mental health problems.These results corroborate the report of the World Health Organization about these being some of the known characteristics and risk factors for female victims of IPV (World Health Organization (WHO), 2021).
The higher values of BMI and smoking behaviors among IPV victims also suggest a lower engagement into bodily self-care and healthy behaviors in this population.Indeed, a multidimensional comprehensive model considers that an acquired self-care deficit can be mediating the link between IPV and physical health problems (Schnurr & Green, 2004;Weaver & Resnick, 2004).Within this model, the authors consider self-care agency as being disrupted in consequence of PTSD, anxiety, or depression disorders among victims of IPV, representing a risk factor for the development of other general health problems (Weaver & Resnick, 2004).PTSD and depression were significantly prevalent among our sample of IPV victims, alongside somatic symptoms, such as difficulty falling asleep, migraines, respiratory problems, and anxiety attacks.
It is equally important to note the high rates of self-injury and suicidal ideation among our sample of IPV victims, behaviors that are commonly linked with higher pain tolerance, higher interoception deficits, and lower levels of trust in bodily sensations (Dodd et al., 2018;Rogers et al., 2021).According to Young et al. (2019), self-injury behaviors can represent a way of dealing with the "interoceptive uncertainty," which is in the root cause of a lack of clarity about the "body's function in emotional experience" (Young et al., 2019, p. 26).Moreover, Ataria (2018) summarizes self-injury as a behavior associated with negative core beliefs regarding the self, which enables the individual to "externalize emotional pain" and provides a sense of "security and control" (p.104), which are often compromised in the context of IPV.
Unexpectedly, the present study did not find impairments in interoceptive awareness and interoceptive cardiac accuracy, suggesting that interoception is preserved in female victims of violence.Considering previous studies (e.g., Machorrinho, Veiga, Santos, Marmeleira et al., 2021a;Reinhardt et al., 2020), it will be worthwhile to examine other interoceptive modalities in the future research (Ferentzi et al., 2018;Garfinkel et al., 2017).
Despite the preserved interoception, IPV victims report stronger experiences of body disownership than non-victims, which is not in accordance with the multisensory integration model (Horváth et al., 2020;Suzuki et al., 2013).Nevertheless, this finding is in line with other studies showing a negative (Tsakiris et al., 2011) or a non-existent (Crucianelli et al., 2018) relationship between interoception and body ownership.The stronger experiences of body disownership found in the present study support the hypothesis of a disrupted sense of body ownership as a repercussion of continued violence (Ataria, 2018;Machorrinho et al., 2019;Van der Kolk, 2015).When continued violence leads to body disownership, the body ceases to be both a subject and an object to invest on.It ends being just a physical object, "not able to touch or to be touched" (Ataria, 2016, p. 225), which is closely related with bodily dissociation, a disconnection from the body that includes feelings of "being separated from the body" or having difficulties at identifying and expressing certain emotions (Price & Herting, 2013).
IPV victims also scored significantly higher on bodily dissociation levels than non-victims.Furthermore, there is evidence of bodily dissociation as a risk factor for anxiety and depression among female victims of IPV (Machorrinho et al., 2021a).Therefore, it is even more interesting to note that the difference between groups in bodily dissociation levels remained significantly after controlling for mental health covariates.
There is increasing research on the neural and neuropsychological consequences of the continued assaults suffered by women in the context of violent relationships.IPV survivors are at a greater risk of having a traumatic brain injury (TBI) caused by violent assaults.Due to the context of fear and shame, the victims may not seek immediate medical support, increasing the long-term consequences of that injury (Monahan, 2019).Women with TBI caused by IPV showed a greater cortical thickness of the paracentral gyrus in comparison with participants with TBI caused by other factors (Likitlersuang et al., 2022).The paracentral gyrus plays an important role on the preparation, initiation and monitoring of movement, and controls for bowel and bladder voiding.It represents an uprising explanation mechanism for functional somatic disorders and pain syndromes, and was recently associated with alexithymia (difficulty identifying and expressing emotions; Terock et al., 2020;Thomann et al., 2015).Accordingly, Monahan (2019) states that the brain tissue injuries caused by repeated assaults lead to "changes in the immune system, inflammation, and neurological changes" (p.810), which are underlying mechanisms for mental and physical health, behavior, and structuring of a bodily self.
Our study shows strong evidence on the link between IPV and impairments in embodiment, namely the sense of body ownership and the disconnection from the body.Nevertheless, we must address as study limitations the assessment of interoceptive accuracy through the Schadry's heartbeat counting task, which has recently shown some reliability issues (Ring & Brener, 2018;Zamariola et al., 2018;Zimprich et al., 2020).Due to difficulties in recruiting female victims of IPV from the community, the present study included IPV victims living in shelters, which can be a significantly different context from the no-IPV participants, namely in terms of opportunities to engage on health and leisure activities, physical environment, and transports (Machorrinho, Veiga, Santos, Marmeleira et al., 2021a).Considering the major value of embodiment for one's health, behavior, and identity structure, there is a strong need for additional research on this matter in survivors of intimate partner violence.Unfortunately, research from Western European countries scarcely addresses these issues on preventive or therapeutic approaches to IPV.Thus, our results highlight one field needing attention, given the complexity and idiosyncrasy of embodiment.
We suggest that future research continue to examine embodiment-related functions of both female and male victims of IPV, and explore associations among embodiment variables, and between those variables and characteristics of IPV.It is crucial to study therapeutic interventions targeted for the recovery of a healthy embodiment in victims of IPV.

Implications for practice
The present study brought to light a part of the role of embodiment-related processes on the health of female victims of IPV.These results can inform victims' support services about the assessment of embodiment-related functions and its implications for mental health, physical health, and behavior.Assessing the traumatized body in the aftermath of violence can be of paramount importance when accomplishing the therapeutic needs of each woman.At least in Portugal, the therapeutic support for victims while living in shelters is scarce and does not usually include any kind of exercise, psychomotor therapy, or body-mind therapy.The knowledge brought by the present study should inform the development of therapeutic interventions addressing body connection and the recovery of the sense of body ownership.Combining bottom-up (sensations' awareness) with top-down (mindful self-regulation) processes is currently thought to be a great approach to trauma interventions (explore Van der Kolk, 2015).
Our results imply the importance of stimulating body literacy among women, and knowledge about the associations between internal bodily sensations and mental health symptoms.That is, the promotion of body connection and awareness of internal sensations can be a part of secondary and tertiary prevention programs, targeting women at risk of engaging in violent relationships.

Conclusion
This study examined embodiment variables of women with and without a history of intimate partner violence.Beyond the expected higher rates of physical and mental health problems, self-injury, and suicidal behaviors among victims of IPV, our results also showed that those women have weaker senses of body ownership and stronger levels of disconnection to the body.
Although a lot is yet to be known about the onset of those impairments and their development and treatment tools, health practitioners must be mindful of the valuable role of embodiment in restructuring the self and recovering from traumatic experiences.Intimate-partner violence victims need embodiment-informed care to be parallel to the attention given to mental health and somatic symptoms.

Table 1 .
Descriptive statistics of sociodemographic and health information.
Note: IPV, Intimate Partner Violence; BMI, Body mass index; PTSD, Posttraumatic Stress Disorder.ap-value of the Mann-Whitney test for non-parametric variablesdiagnosis of PTSD (p = .014)and Depression (p < .001).In our sample, IPV victims were also reported to have previously engaged in more self-injury (p < .001)and suicidal behaviors (p < .001).

Table 2 .
Results for the comparison of embodiment-related variables between IPV and no-IPV groups.
c Independent samples t-test.