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Study · Measured the body's own peptide · 2025

2 results

How does neurochemistry affect attachment styles in humans? The role of oxytocin and the endogenous opioid system in sociotropy and autonomy - A systematic review.

Snowdon-Farrell A, Attal C, Nikkheslat N, Pariante C, Young AH, Zahn R

Neuroscience and biobehavioral reviews26 Dec 2024Cited by 3 (Europe PMC)

PMID39732223 (opens in a new tab)DOI10.1016/j.neubiorev.2024.105994 (opens in a new tab)PepBankPUB-39732223
Publisher pagePubMedAsk about this study
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Summary

Oxytocin was hypothesised to play a critical role in forming and maintaining secure attachments, shown to confer resilience against affective disorders. The endogenous opioid system has also emerged as a key player in attachment dynamics. In this pre-registered systematic review, we investigated whether individual differences in the functioning of these neurochemical systems are related to attachment styles, following PRISMA guidelines. As predicted, individuals with higher oxytocin function exhibited more secure attachment styles (p = .006, n = 12 studies) and less insecure attachment styles (p = .021, n = 16 studies). Contrary to our hypothesis, we found no association of endogenous opioid function with insecure (p = 0.549, n = 11 studies) or secure attachment styles (p = .065, n = 11 studies). The lack of association between endogenous mu-opioid function and attachment styles remains inconclusive due to inconsistencies in the neurochemical measurements and lack of eligible studies. Therefore, further investigations into the role of the endogenous opioid system in attachment styles are needed. Our findings corroborate the hypothesis that individual differences in oxytocin function relate to differences in attachment styles.
CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study2

No result from this study comes from a test of the peptide.

Natural levels measured2

These results measure the body's own peptide. Nobody was given the peptide. They are not evidence about taking it. They are left out of key results, evidence counts and charts.

  1. 01HumanEndogenous levelSystematic reviewOther

    In humans, higher oxytocin function was associated with more secure attachment styles across 12 studies (p = .006).

    In plain wordsIn people, a more active natural oxytocin system was linked to more secure attachment.

    Peptide
    Oxytocin
    Outcome
    IncreaseOxytocin function and secure attachment
    Study

    n: not reported in source

    Outcome group
    Social behavior and cognition · Mental health and mood

    Source sentences

    Summary
    individuals with higher oxytocin function exhibited more secure attachment styles (p = .006, n = 12 studies)
    1 context sentence
    Summary · context
    In this pre-registered systematic review, we investigated whether individual differences in the functioning of these neurochemical systems are related to attachment styles, following PRISMA guidelines.

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

  2. 02HumanEndogenous levelSystematic reviewOther

    In humans, higher oxytocin function was associated with less insecure attachment styles across 16 studies (p = .021).

    In plain wordsIn people, a more active natural oxytocin system was linked to less insecure attachment.

    Peptide
    Oxytocin
    Outcome
    DecreaseOxytocin function and insecure attachment
    Study

    n: not reported in source

    Outcome group
    Social behavior and cognition · Mental health and mood

    Source sentences

    Summary
    less insecure attachment styles (p = .021, n = 16 studies)
    1 context sentence
    Summary · context
    In this pre-registered systematic review, we investigated whether individual differences in the functioning of these neurochemical systems are related to attachment styles, following PRISMA guidelines.

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 2Current

    11 Oct 2026, 00:50 UTC

    Study results updated

  2. Version 1

    9 Oct 2026, 02:47 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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