Elsevier

Medical Hypotheses

Volume 83, Issue 3, September 2014, Pages 276-281
Medical Hypotheses

Childhood attachment and schizophrenia: The “attachment-developmental-cognitive” (ADC) hypothesis

https://doi.org/10.1016/j.mehy.2014.05.017Get rights and content

Abstract

Schizophrenia is a complex psychiatric syndrome whose exact causes remain unclear. However, current scientific consensus has highlighted the importance of neurodevelopmental and neurocognitive processes in the development of schizophrenic symptoms. Research over the past three decades, motivated by the findings of the World Health Organization’s large-scale studies, has highlighted the importance of psychosocial adversities – including childhood abuse and neglect – in this disorder. In this paper, I propose a hypothesis based on John Bowlby’s framework of attachment theory, which I have termed the attachment-developmental-cognitive (ADC) hypothesis. The ADC hypothesis integrates recent developments related to (1) existing models of schizophrenia, (2) studies examining the effect of attachment on brain biology and cognitive development, and (3) various known facts about the course and outcome of this disorder. In doing so, it explains how disturbed childhood attachment leads to core psychological and neurochemical abnormalities which are implicated in the genesis of schizophrenia and also affect its outcome. The ADC hypothesis compasses and expands on earlier formulations, such as the “social defeat” and “traumagenic” models, and has important implications regarding the prevention and treatment of schizophrenia. Ways of testing and refining this hypothesis are outlined as avenues for future research. Though provisional, the ADC hypothesis is entirely consistent with both biological and psychosocial research into the origins of schizophrenia.

Section snippets

Introduction what causes schizophrenia?

Schizophrenia is a complex psychiatric syndrome which has been reported across a wide range of countries and cultures, though its incidence varies according to region [1]. The symptoms of schizophrenia are diverse, including delusions and hallucinations (positive or “reality distortion” symptoms), disturbances in the organization of behavior and language (disorganization) and deficits in social and occupational functioning as well as cognition (negative or “psychomotor poverty” symptoms) [2],

Psychosocial theories of schizophrenia and the “DOSMD challenge”

In the second half of the last century, the World Health Organization conducted two landmark studies which examined the long-term outcome of schizophrenia: the International Pilot Study of Schizophrenia (IPSS) [8], [9] and the Determinants of the Outcome of Severe Mental Disorders (DOSMD) study [10]. A consistent result across both these studies was that the outcome of schizophrenia was generally more favorable in “developing” countries, such as India and Nigeria, than in “developed” countries.

Attachment theory: then and now

Attachment theory, as initially elaborated by John Bowlby in Attachment and Loss [25], [26], [27], is a developmental theory which explains healthy childhood development – as well as psychopathology – on the basis of the phenomenon of attachment. According to Bowlby, attachment to a significant figure – usually a parent – is a fundamental biological mechanism that has evolved to protect the young of a species from predators [25]. However, this is not the only function of an attachment bond.

Evidence in support of a role for attachment in schizophrenia

Schizophrenia is now conceptualized as a neurodevelopmental disorder, which means that factors influencing the development of the brain during childhood and adolescence – which include not just severe forms of trauma, but the threatened or actual disruption of an attachment bond and even subtler forms of “insecure attachment” – must be given their due importance. Incidents such as physical or sexual abuse may not only be pathogenic in themselves, but may also be markers of more profound or

The hypothesis

The hypothesis proposed here – which I have termed the “attachment-developmental-cognitive” (ADC) hypothesis of schizophrenia – postulates that disturbances in childhood attachment, including neglect and abuse, lead to deficits in neural representation of the self and others, impaired “theory of mind” skill, and sensitization of the mesolimbic dopamine pathway, which is relevant to positive symptom formation [40]. Thus, such an individual is not only “sensitized” to stress [41], but has

Findings explained by this hypothesis

The advantage of this hypothesis is that it incorporates, and extends, the traumagenic and neurodevelopmental models that represent the cutting edge of psychological and biological research into the causes of schizophrenia. In particular, the attachment-neurodevelopmental hypothesis explains:

  • (1)

    The association between schizophrenia and not only abuse and neglect [21], [42], but parental separation as well [20], [23], as all these could lead to the consequences described above.

  • (2)

    The documented

Biological plausibility of the ADC hypothesis

Though the points listed above are suggestive, a far more important question is whether the structural and functional brain changes caused by disrupted childhood attachment parallel the well-established changes seen in the brains of patients with schizophrenia; if this is not the case, then the hypothesis would have to be discarded. However, there are a number of striking similarities between these two sets of changes, as enumerated below (Table 1).

Though the above evidence is entirely

Testing and refining the ADC hypothesis

The role of attachment in schizophrenia can be tested both retrospectively and prospectively. In the former case, patients with a diagnosis of schizophrenia can be interviewed with structured instruments to assess both early (parental) and current measures of attachment, and their relationship to variables such as age at onset, disease course, treatment response, symptom profile, and outcome. If the hypothesis proposed above is correct, we would expect a strong correlation to be found between

Limitations of the hypothesis

The model proposed above is consistent with the neurocognitive and neurodevelopmental models of schizophrenia, is supported by existing literature, and extends the efforts of some authors (such as Read’s “traumagenic model”) to examine the relationship between childhood adversity and psychosis. It also provides an empirically valid theoretical framework – attachment theory – in which this relationship can be examined. However, the following limitations must be borne in mind:

  • (1)

    Disturbed attachment

Implications of the hypothesis

The ramifications of an attachment-based hypothesis for schizophrenia are considerable, and can be considered at three levels: preventive, therapeutic and translational.

From a preventive point of view, the most immediate application of this model would be to children and adolescents who are considered to be at a high risk of developing schizophrenia, either genetically or on the basis of their symptoms. Family intervention in such patients, aimed at strengthening attachment bonds and modifying

Conclusion

The ADC hypothesis outlined above is provisional, and is clearly in need of further support from clinical and community research. Besides, it cannot be viewed as an unitary “theory of schizophrenia”. Despite this, an attachment-informed perspective on schizophrenia, as outlined in this hypothesis, is consistent with both biological and psychosocial models of this disorder, strengthens them, and explains their inter-relationships. This property sets it apart from other theories of schizophrenia

Financial support

No extramural funding was provided for this work.

Conflicts of interest

None.

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