1. Introduction
According to the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V), depression is identified by characteristics such as low mood or pleasure, sleep disorders, appetite disorders, difficulty in concentration and decision-making ability, restlessness or sluggishness, decreased energy, feeling of worthlessness, and suicidal ideation ranging from mild to severe levels (APA, 2013). Based on epidemiological studies, depression is one of the most common mental disorders worldwide (Kader Maideen et al., 2014; Richards, 2011; Silva et al., 2014; Vilagut et al., 2016) and includes all age groups (Larsson et al., 2016; Mojtabai, Olfson, & Han, 2016; Sengupta & Benjamin, 2015; Silva et al., 2014). In addition, depression is highly comorbid with other physical (Andrade et al., 2015; Kang et al., 2015; Sartorius, 2017) and psychological (Flory & Yehuda, 2015; Leyhe et al., 2017; Mikocka-Walus et al., 2016; Reiter et al., 2015; Ugochukwu et al., 2016) disorders, and affects people’s different levels of individual, interpersonal, and social functioning (APA, 2013). Interpersonal relationships are considered one of the most fundamental areas in which depressed individuals have difficulties (Santini et al., 2015). 
Behavioral, cognitive, and interpersonal approaches have suggested that factors such as social skills deficits, specific behavioral characteristics in interpersonal relationships (Segrin, 2001), defective feedback patterns, such as an extreme search for confidence in interpersonal relationships and expectation of rejection, and preference for negative and authoritarian feedbacks are effective in depression (Evraire & Dozois, 2011; Joiner Jr, 2000). Although these models and related research have attempted to explain the interpersonal factors involved in the onset, persistence, and recurrence of depression, they have neglected or paid less attention to more fundamental factors such as object relations and communication components considered in psychoanalytic theories. In this regard, Hams, Hagan, and Joiner (Hames et al., 2013) state that to develop a comprehensive model of depression, interpersonal and non-individual factors of different theories must be combined to provide a broader understanding of depression.
Theoretically, two branches of the psychoanalytic approach, namely the object relations theory and Luborsky’s Core Conflictual Relationship Theme (CCRT) view, have examined the interpersonal relationships of depressed individuals. They have found that relational components are an essential part of the pathology of depressive disorder (Luborsky & Crits-Christoph, 1998). A fundamental assumption in the object relations theory is that many psychological problems result from internalizing defective relational patterns (especially communication with parents) in psychological structures and the repetition of such patterns in everyday life (Fonagy et al., 2007). Regarding depression, clinical experiences and research show that the central issue in the past of these patients is not the experience of loss but the deprivation experienced in their relationships with primary caregivers. In addition, flawed representations resulting from such relationships predispose them to experience depression in the face of loss (Lizardi & Klein, 2005; Taubner et al., 2011). 
Fairbairn’s object relations states that depression results not from the nature of libido impulses but the problems experienced in object relations. In Fairbairn’s relational thinking, the “self” is an autonomous organization that, within its psychological capacity framework, seeks to confront the “set of social and psychological conditions” (Orbach, 2008) in which it is born and strives to alchemize chaos while turning it into a reality to reach a sense of connection repeatedly, albeit at the cost of psychological integration. In Fairbairn’s view, depression is not something to be dealt with but a part of the self while living in the catastrophic age of emotional deprivation frozen by an impossible object in time; it is “unique, necessary, and irreplaceable” and at the same time “harmful, unlovable, deceptive (non-sacrificial love), sinful, making worthless, and narcissistic” (de Matos, 2020). Understanding depression through the framework of Fairbairn’s relational thinking requires comprehending how a person communicates with others through stabilized patterns of object relations in the intra-psychological structure and how depression hinders the ongoing process of self-construction through interaction with others. Withdrawal from the intra-psychological structure allows the individual to recall the connection to the internalized object, attach parts of the self that merge with the bad objects, and maintain an essential embodiment of their identity following the conflict between internal and external realities (Fang, 2020). For example, by reviewing studies on the role of the child-parent relationship in depression with different methods, Blatt and Homann (1992) confirmed the hypothesis that early experiences such as inattention, criticism, control, disapproval, and lack of support by parents lead to representing parents as critical and unsupportive. 
Representing the self as vulnerable, weak, and inadequate, thus re-experiencing them in later relationships, leads to helplessness and depression. Zemore and Rinholm (1989) also investigated the importance of negative representations of parents in vulnerability toward depression. They concluded that these representations were common in girls with a disturbing or controlling mother and boys with a cold and rejectful father. Herbert et al. (2010) examined the relationship between attachment (both parental and peer) and depressive symptoms in young adults in Northern Ireland. Their results supported the continuity of attachment styles perceptions across the life span and revealed that perceptions of early attachment experiences, as well as continuing peer attachment styles appeared to be predictive of later depressive symptoms. Weiss and Lang (2000) showed that the relationship between the self and the object becomes replaced by a pathological relationship between parts of the self. As psychoanalytical and phenomenological-hermeneutical approaches congruently show, one reason why mourning cannot proceed and feelings of guilt cannot be worked through is that depressive patients need a symbiosis, idealizing the type of identification with their objects to stabilize their identity. 
Luborsky expresses the CCRT concept in line with the object relations view. The CCRT includes the mental representation of interpersonal relationships, including their associated desires and emotions (Crits‐Christoph et al., 1994; Luborsky & Crits-Christoph, 1998). Key past relationships shape these patterns and provide a mental blueprint for guiding new interactions, although they often occur unconsciously. Concepts imply that CCRT underlies various personality theories through the basic concept of transference pattern (Freud, 1958) to relationship schema (Young et al., 2006), attachment style (Levy et al., 2018), and personality traits (Grenyer, 2018). Indeed, the rich history of attachment theory (Ainsworth & Bowlby, 1991) provides a unique developmental lens for understanding the early formation of the relationship between the infant and the caregiver and the potential for their disorder. These theories are integrated into a pattern of conflicting or maladaptive central relationships between the self and others that create psychological symptoms (Grenyer, 2002). Luborsky and Crits-Christoph (1998) have identified three critical components in the interpersonal relationships between healthy individuals and patients. These three components are wishes, tendency, demand, or desire that the individual seeks in their relationships; response From the Other (RO), a response that the individual perceives or receives from others; and response of self (RS), emotional, intellectual, or behavioral reaction of an individual in response to another person. In this view, it is assumed that according to these three components, everyone has a different function in their relationships, and the symptoms are formed according to the person’s difficulty in these components. Regarding depression, it is assumed that the symptoms are formed because the patient exaggerates the dangerous situation and expects failure and helplessness. Symptoms are formed to cope with the expected helplessness and the potential anxiety caused by the dangerous situation (Barber & Crits-Christoph, 1995).
Given the assumptions of Luborsky’s view on the importance of interpersonal relationships, the role of object relations in how the pathology develops, and the importance of early interpersonal relationships, this study was conducted to compare normal individuals with patients suffering from major depression in the object relations and the CCRT.

2. Participants and Methods
Study participants
This research is a cross-sectional study. The statistical population included all patients with major depressive disorder and normal individuals living in Tehran. The patient sample consisted of 30 people with major depressive disorder referred to private psychotherapy clinics in Tehran City, Iran. These patients were selected to participate in the study by convenience sampling through interviews with a psychologist and structured clinical interviews (SCID-I and SCID-II). Meanwhile, the normal sample consisted of 30 employees of Tehran University of Medical Sciences who were selected by purposive sampling. All participants completed the informed consent form for participating in the study. The inclusion criteria included having diagnostic criteria for depression based on the DSM-IV, age range of 20 to 60 years, and having at least a high school diploma. The exclusion criterion included the presence of other Axis I and II disorders simultaneously with depression.

Study instruments
Structured clinical interview for DSM-IV axis I disorders 
The structured clinical interview for DSM-IV Axis I Disorders (SCID-I) was designed by First and Gibbon (2004) to assess the DSM-IV Axis I disorders in clinical and research work. This tool is performed in a 60 to 90-minute session, and the required minimum age is 18 years. In evaluating the diagnostic inter-evaluator reliability, Glasofer et al. (2015) reported “relatively good” to “good” reliability for most diagnoses. Results revealed “moderate” to “excellent” inter-rater agreement of the Axis I Disorders, while most categorically and dimensionally measured personality disorders showed excellent inter-rater agreement (Lobbestael, Leurgans, & Arntz, 2011).  The Persian version of this questionnaire was translated by Sharifi et al. and administered to a sample of 299 subjects aging from 18 to 65. The results showed good diagnostic agreement (kappa above 0.6) for most specific and general diagnoses. The comprehensive agreement has been reported to be 0.52 for all current diagnoses and 0.55 for total lifetime diagnoses (Shooshtari et al., 2007).

Structured clinical interview for DSM-IV axis II disorders 
First and Gibbon (2004) designed and conducted the structured clinical interview for DSM-IV Axis II disorders (SCID-II) to assess personality disorders. This tool can diagnose personality disorders in categorical and dimensional forms. Glasofer et al. (2015) have reported the inter-evaluator reliability for all personality disorders, except for antisocial personality disorder, from relatively good to good. In this study, the inter-evaluator reliability for dimensional diagnoses of personality disorders has been reported to be higher than categorical diagnoses (Glasofer et al., 2015). The Persian version of this tool has been prepared by Sharifi et al. (2009), and several clinical psychology professors have confirmed its content and face validity. The reliability of this interview was obtained at 0.87 with the retest method at a 1-week interval (Sharifi et al., 2009).

Symptom Checklist-90-revised (SCL 90-R)
The symptom checklist-90-revised (SCL 90-R), designed by Derogatis, Rickels, and Rock (Derogatis, Rickels, & Rock, 1976), includes 90 questions to assess psychological symptoms for one week. The questions of this test include 9 different dimensions of physical complaints, obsessive-compulsive disorder, interpersonal sensitivity, depression, paranoid thoughts, anxiety, hostility, phobia, and psychosis. The test’s scoring and interpretation are based on three indicators: 1) the overall coefficient of symptoms; 2) the criterion of the discomfort coefficient of positive symptoms; 3) the sum of positive symptoms. The total severity of the client’s symptoms can be measured by the elevation degree of the index of the overall coefficient of symptoms (Derogatis, 1992). In assessing the test’s internal consistency, the highest and the lowest correlation coefficients were reported as 0.95 for depression and 0.77 for psychosis. In the Persian version, retest coefficients for different dimensions have been reported to range from 0.78 to 0.90, with a total retest coefficient of 0.80 (Bagheriyazdi, Bolhari, & Shahmohammad, 1994).

Bell Object Relations Inventory 
The Bell object relations inventory (BORI) is a 45-item, true or false questionnaire. It involves four subscales: alienation (ALN), describing the individual’s ability to experience trust in interpersonal relationships; insecure attachment (IA), expressing sensitivity toward rejection and the possibility of being harmed by others in interpersonal relationships; egocentricity’ (EGC), describing an individual’s tendency to perceive others in relation to themselves; social incompetence (SI), measuring an individual’s perception of their ability to successfully participate in social activities (Twomey, Kaslow, & Croft, 2000). Bell, Billington, and Becker (1986) have reported the Cronbach α coefficient and the reliability of the two halves of the test for all four subscales to range from 0.78 to 0.90 and the retest reliability coefficient to range from 0.58 to 0.85. The internal consistency of the subscales in the Persian version was obtained from 0.66 for SI to 0.82 for ALN (Bakhtiari, 2000).

Central Relationship Questionnaire 
The central relationship questionnaire (CRQ) is a self-report tool developed by Barber, Foltz, & Weinryb (1998) and revised in 2008 (McCarthy, Connolly Gibbons, & Barber, 2008). This questionnaire evaluates the basic patterns of relationships with others and has three components: Wishes, the response from the other (RO), and the response of self (RS). The subject considers each of these three components about the person with whom they have a romantic relationship, i.e., mother, father, spouse, and best friend, and scores each of them on a 7-point Likert scale from 1 (never true) to 7 (always true) (McCarthy et al., 2008). The evaluation results of psychometric properties indicate the appropriate reliability coefficient of this tool for the main components (Cronbach’s alpha ranges from 0.78 to 0.95). Also, total correlations for wishes, RO, and RS subscales have been reported to be 0.44-0.90, 0.58-0.85, and 0.42-0.87, respectively (Weinryb et al., 2000). In the revised version, the Cronbach α values for primary subscales and second-order factors were estimated to be 0.94 and 0.88, respectively (McCarthy et al., 2008). The psychometric properties of this questionnaire were assessed in the present study. To this aim, after translation into Persian, the face and content validity of this questionnaire were obtained through the approval of several clinical psychologists. Next, after removing six questions because of cultural issues that were done in coordination with the toolmaker, 30 people were selected by convenience sampling method to obtain the retest reliability of this questionnaire. The questionnaire was administered to them twice with an interval of two weeks. The results regarding calculating the reliability of second-order factors for wishes, RO, and RS ranged 0.40-0.89, 0.38-0.83, and 0.35-0.92, respectively.

Study procedure
First, to determine the validity and the reliability of the CRQ, 30 people from Tehran Psychiatric Institute were selected, and this questionnaire was administered to them. The main stage of the research was conducted after determining the validity and reliability of the CRQ. At this stage, 30 patients with major depression among those were referred to private clinics and according to the psychiatrist and SCID diagnostic interviews, met the inclusion criteria, were selected by the accessible sampling method. Every two questionnaires of CRQ and BORI were performed on them by describing the purpose and obtaining patients’ satisfaction. In the next stage, the control group, which included 30 people in Tehran, was selected by purposive sampling and homogenized in terms of age, sex, marriage, and level of education. Then, to ensure the absence of psychological symptoms in the control group, the SCL-90 questionnaire was administered to them, and individuals with a GRI score of less than one entered the next stage of the study. Subsequently, two questionnaires of CRQ and BORI were performed on them by stating the purpose and obtaining their consent. Finally, the data were collected and analyzed.

Data analysis
The SPSS software version 26 and multivariate analysis of variance (MANOVA) were used to analyze the data obtained from the study. The Chi-square and the t test were used to evaluate data homogeneity regarding demographic variables.

3. Results
The analysis of covariance (ANCOVA) of demographic data showed no significant difference between the two groups in terms of age (t=0.19, P>0.05), gender (χ=20.00, P>0.05), marital status (χ=24.06, P>0.05), and education level (I2=1.41, P>0.05). Accordingly, they were homogeneous.
The MANOVA test was used to evaluate the variable effect of depressed and normal groups on the subscales of the ORI and the second-order factors of the CRQ. The results of this study using the Wilkes’ lambda test on the linear composition of the subscales of the ORI and the CRQ showed a significant effect on the group.
Regarding the status of object relations of the study groups, there was a significant difference between the depressed and normal groups in all four subscales of alienation, insecure attachment, egocentricity, and social incompetence (Table 1).

In addition, the mean and standard deviation of the CCRT in the two groups of depressed and normal participants in relation to spouse or partner, mother, father, and best friend are reported in Table 2.

The data were evaluated using the Kolmogorov-Smirnov test, and the results showed that they had the required normality. Levene’s homogeneity of variance results also showed the homogeneity of variance between the normal and the depressed groups.
The results of MANOVA for examining the effect of the depressed and the normal groups on the component of wishes among the subscales of the CCRT show a significant difference between the group with major depression and the normal group in the subscale of being annoying in all four relationships, i.e., the relationship with spouse or partner, mother, father, and best friend. Also, the two groups were significantly different in their relationship with the spouse or partner in the subscale of “be independent.” On the subscale of “be intimate,” there were significant differences in all four relationships with spouse, mother, father, and best friend. Finally, there was a significant difference between the two groups in the “be submissive” subscale related to the spouse (Table 3).

Additionally, according to Table 3, there was a significant difference between the two groups in the subscale of “he/she is hurtful” in all four relationships with spouse, mother, father, and friend. There was also a significant difference in the three relationships of mother, father, and best friend in the “he/she is loving” subscale.
The results also showed a significant difference between the two groups in the “I am autonomous” subscale in relationships with spouse, mother, father, and best friend. Meanwhile, there was a significant difference in the subscale of “I am distant” in relationships with spouse, mother, father, and best friend. In the subscale of “I am intimate,” a significant difference was observed in the three relationships with spouse, mother, and best friend. Finally, in the subscale of “I am sexual,” there was a significant difference in the relationship with the spouse (Table 3).

4. Discussion
The present study aimed to compare the object relations and the CCRT in patients with major depression and normal individuals. The comparison of object relations in the group of patients with depression and the normal group showed that both groups were significantly different in all four subscales of ALN, IA, EGC, and SI. Meanwhile, the mean score of depressed patients in all four subscales was higher than that of the normal group. In addition, the results related to the CCRT showed a significant difference between depressed patients and normal individuals on several scales of all three components of Wishes, RO, and RS.
In general, the results related to the object relations variable in depressed individuals are consistent with the findings of the two studies, showing that the object relations of depressed patients have problems because of defective internal representations of close relationships (Blatt & Homann, 1992; Huprich et al., 2007). Also, in line with the findings of this study, another research has shown that these patients have a more negative representation of themselves and significant others in their lives compared to the general population (Gara et al., 1993). Although there is little research on the BORI subscales in depressed patients, the present study’s findings can be explained theoretically by object relations and attachment theories.
Regarding the results of the EGC subscale, individuals who have high scores on this scale consider others not as distinct personalities but as options that can meet or fail their needs and interests; meanwhile, the ability of empathy and emotional investment is low in their relationships (Bell et al., 1986). Depressed patients suffer from the internal structure of a weak and vulnerable self and are easily exposed to the threat of disintegration. Thus, because of the deficiencies in this structure, these patients see others not as distinct personalities but as a means of compensating for internal deficiencies (Bell et al., 1986). The intra-psychological structure provides a home not only for the poorly internalized object but also for repressed aspects of the self-experienced. Together, they form the repressed part of the self and a significant part of the individual’s identity. Like a child who can tolerate the badness of a bad object but cannot tolerate its separation or loss, a person with depression cannot give up the existing intra-psychological structure of the self that is the effect and remnants of the relationship experiences between parts of the self. Since there is a need to constantly recall the original object relations, complete power resistance occurs to any change. Therefore, the links between the sub-self and the internal object are maintained (Fang, 2020). Given Fairbairn’s concept of secondary repression, it would be very reductionist to think of depression as merely a case of self-directed anger to the given-up internal object. In contrast, it is an act of aggression that is internalized along with the bad object relations in the individual’s intra-psychological structure and serves as a fuel for further suppression of the re-emergence of the bad object and part of the sub-self-associated with them (Fang, 2020). 
The insecure attachment subscale shows extreme sensitivity to rejection, morbidity concerns about being loved and accepted by others, dependence on others to meet the needs, feelings of inner emptiness, and fear of being left and loss that lead to the relentless efforts of these individuals for building a relationship with anyone whom they think can eliminate their fears and satisfy their quest for emotional security (Bell et al., 1986). Ainsworth and Bowlby (1991) state that as a result of not meeting their need for attachment (which aims to maintain a sense of security), these patients internalize patterns of themselves as inadequate and unlovable and patterns of others as rejecting and punishing in childhood, and these internalized patterns affect their feelings, beliefs, and behaviors (whether consciously or unconsciously) in the face of losses or rejections in the future. The goal of these patients in relationships is intimacy, but lack of self-confidence and fear of being rejected lead them to seek unrealistic levels of closeness, emotional intimacy, and support from others (Busch, Rudden, & Shapiro, 2016; Obegi & Berant, 2010). SI is another subscale that determines the object relations style of depressed patients. This scale reflects individuals’ perception of their ability to successfully engage in social activities and make friends. People with high scores on this scale suffer from inability and a lack of self-confidence in establishing and maintaining friendships. Worry and anxiety in the interpersonal relationships of individuals with a feeling of SI lead to recurring maladaptive patterns of attachment and self-destructive behavior and the need to maintain any established relationships (Bell et al., 1986). The social ALN subscale indicates distrust and difficulty in establishing intimacy and interdependence in relationships, and its higher score in patients with depression means this group has a more pessimistic view of the environment, the motivation of others, and their inability to form a mature relationship based on interdependence (Bell et al., 1986). In this regard, Abraham, Klein, and Winnicott consider part of the distrust and pessimism in depressed patients to be the presence of severe aggression (whether intrinsic or environmental) and conflict with it, leading to its suppression and projection to the environment and others (Lubbe, 2010; Summers, 2014).
The results related to the CCRT in depressed patients and normal individuals showed that compared to normal individuals, the CCRT in depressed patients in the component of wishes was in the form of a higher tendency toward aggression and reluctance to intimacy. In the component of RO, this was in the form of the perception of significant others as being hurtful and not receiving love from them. Moreover, in the component of RS, it was in the form of being more distant and having no sense of autonomy. In line with the obtained findings, Freud and Abraham stated that depression is formed because the person has inwardly directed the aggressive impulses that should have been sent to an object in the outside world (Kendell, 1970). It can be maintained that this anger and aggression prevents the individual from experiencing intimacy in its actual form in interpersonal relationships because the depressed individual is angry with external objects. The studies of Becker and Lesiak (1977) and Goldman and Haaga (1995) have also confirmed the positive association of conflict with anger and depression severity. These findings suggest that depression severity can be predicted by latent aggression, irritability, and pessimism toward others; also, the levels of anger and its repression and the fear of expressing it are higher in the reports of depressed patients compared to the control group. 
In explaining the findings based on Luborsky’s view, because depressed individuals have problems in the component of Wishes and their wishes are repulsed (aggression and lack of intimacy with others), their expectations from others act toward these wishes, and they perceive individuals as those who tend to hurt and not tend to love. This collection together makes them distance themselves from others, and as a result, their feelings of anger and lack of intimacy with others are intensified. The conflicting aspect of the CCRT also refers to the contrast between what one wants and what one receives (for example, a tendency to be praised [Wishes]) but perceives another as rejecting (RO), leading to the feeling of depression (Hegarty et al., 2020).

Limitations and Suggestions
This study had some limitations. The first was the use of pencil-paper tests in conducting the research. It is suggested that future research be conducted using in-depth interviews or projection tools. Given that limited studies have been conducted to investigate the object and relations style and the CCRT in patients with depression, it is suggested in future studies that individuals in different age groups and other subsets of mood disorders and clinical populations be examined for interpersonal relationships.

4. Conclusion
Considering the study findings, from the perspective of object relations and the CCRT views, one of the dimensions of individuals’ vulnerability to depression is their interpersonal relationships and internal representations of relationships regarding significant others in life, both in the past and the present. It seems that in the diagnosis, pathology, and treatment of depressed patients, the roots of the formation of destructive wishes concerning important objects of life should be explored and how to internalize and repeat communication patterns in current relationships should be examined and treated.

Ethical Considerations
Compliance with ethical guidelines
The Research Ethics Committee of the Iran University of Medical Sciences approved this study (Code: IR.IUMS.REC.19539.121.03.91).

Funding
The paper was extracted from the MSc thesis of the first author, Department of Clinical Psychology, School of Behavioral Sciences and Mental Health (Tehran Institute of Psychiatry), Iran University of Medical Sciences, Tehran.

Authors' contributions
All authors equally contributed to preparing this article.

Conflict of interest
The authors declared no conflicts of interest.

Acknowledgments
We thank all the participants who contributed samples to the study.


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