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Specific Study Information

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Output: Peer-Reviewed Publications

Within the CARE study, we examined the effects of interaction quality on neural synchrony during a problem-solving task in N= 42 dyads of mothers and their preschool children by using dual-functional near-infrared spectroscopy (fNIRS). We found increased neural synchrony in bilateral prefrontal cortex and temporo-parietal areas during cooperative as compared to individual problem solving.

Higher neural synchrony during cooperation correlated with higher behavioural reciprocity and neural synchrony predicted the dyad’s problem-solving success beyond reciprocal behaviour between mothers and children. State-like factors, such as maternal stress and child agency during the task, played a bigger role for neural synchronisation than trait-like factors, such as child temperament.

Our results emphasise neural synchrony as a biomarker for mother-child interaction quality. These findings further highlight the role of state-like factors in interpersonal synchronisation processes linked to successful coordination with others and in the long-term might improve the understanding of others.

Nguyen, T., Kayhan, E., Schleihauf, H., Matthes, D., Vrtička, P., Hoehl, S. (2020). The effects of interaction quality on neural synchrony during mother-child problem solving. Cortex, Volume 124, Pages 235-249, https://doi.org/10.1016/j.cortex.2019.11.020. OPEN ACCESS.

See also this recent blog about the main study findings.

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Within the CARE study, we also assessed inter-brain coherence during a 4 minute long natural verbal conversation in N= 40 dyads of mothers and their preschool children by using dual-functional near-infrared spectroscopy (fNIRS). The 4 minute natural conversation was split into eight segments of 30 seconds and inter-brain coherence was calculated separately for each segment. In addition, every conversational turn was behaviourally coded for its underlying qualities comprising: 1) turn-taking (i.e. whether dyads engaged in reciprocal utterances), 2) turn relevance (i.e. whether turns shared thematic content), 3) turn contingency (i.e. a turn provided requested information), and 4) turn intrusiveness (i.e. whether the turn allowed time to respond / interrupted the speaker).

Results revealed that neural synchrony in temporo-parietal and lateral prefrontal regions increased throughout the conversation on average. Critically, when we considered how often mothers and children took turns, higher neural synchrony was associated with higher turn-taking in later epochs of the conversation.

Our study shows that children and mothers synchronise their brain activity during natural verbal conversation and that neural synchronisation increases over time when mother and child engage in more verbal turn-taking. This observed link between conversational turn-taking and neural synchronisation opens up new possibilities to understand the potential functional role of neural synchronisation during verbal exchanges.

See also this recent blog post for a summary.

Nguyen, T., Schleihauf, H., Kayhan, E., Matthes, D., Vrtička, P., Hoehl, S. (2021). Neural synchrony in mother-child conversation: Exploring the role of communicative features. Social Cognitive Affective Neuroscience, Volume 16, Issue 1-2, Pages 93–10. https://doi.org/10.1093/scan/nsaa079. OPEN ACCESS.

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Building upon CARE Paper N° 1 (see above), this paper as part of the D-CARE study examined the effects of interaction quality on neural synchrony during a problem-solving task in N= 66 dyads of fathers and their preschool children (age 5) by using dual-functional near-infrared spectroscopy (fNIRS).

Similar to mother-child dyads, we also observed increased inter-brain synchrony in father-child dyads during cooperative as compared to individual problem solving (and rest) in dorsolateral prefrontal and temporo-parietal brain areas. Some other patterns, however, differed in father- as compared to mother-child dyads, and these are discussed in the paper. In addition, we for the first time report that the father’s attitude toward his role as a parent was related to inter-brain synchrony during cooperation.

These results extend our knowledge on parent-child interaction and inter-brain synchrony and for the first time highlight the importance of the father’s attitude to parenting on a bio-behavioural synchrony level.

Nguyen, T., Schleihauf, H., Kungl, M., Kayhan, E., Hoehl, S.*, & Vrtička, P.* (2021). Interpersonal neural synchrony during father-child problem solving: A fNIRS hyperscanning study. Child Development, July/August 2021, Volume 92, Number 4, Pages e565–e580. *= these authors share senior authorship. https://doi.org/10.1111/cdev.13510. OPEN ACCESS.

Press releases:
►University of Essex (12 January 2021)
►University of Vienna (12 January 2021)

For a selection of press reports, see here.

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A second paper as part of the D-CARE study describes an investigation of hypothalamus volume in N= 50 fathers of 5-6 year-old children and N= 45 non-fathering men. All men underwent structural magnetic resonance imaging (MRI) scanning with subsequent manual volumetric parcellation of the hypothalamus.

Most studies on mammalian caregiving and attachment have focused on the mother-child relationship, particularly in humans. Yet, changing societal roles of male caregivers have highlighted the necessity for research with fathers.

In this pre-registered study, we examined the volume of the hypothalamus, an important subcortical brain area for caregiving and attachment behavior using a novel technique to identify the human hypothalamus in 3T MRI. Furthermore, we employed three self-report measure to assess interindividual differences in caregiving beliefs in fathers, and attachment style across all men.

Self-reported caregiving beliefs, including belief in the importance of a father’s role and enjoyment of the child, were positively related to total hypothalamus volume. A follow-up analysis furthermore showed that fathers’ beliefs were related specifically to tuberal hypothalamus volume, while enjoyment of the child was not associated with volume in any specific hypothalamus sub-region. We did not observe any significant associations between hypothalamus volume and attachment style across all men (after correction for multiple comparisons), and no difference in hypothalamus volume between fathers and non-fathers.

Together, this study suggests that there is interindividual variability in the association between brain structure and caregiving beliefs in fathers, warranting further research.

►University of Essex Press Release
►The Conversation UK piece on this study

Long, M., Puhlmann, L., Vrtička, P. (2021). Hypothalamus volume in men: Investigating associations with paternal status, self-reported caregiving beliefs and adult attachment style. Social Neuroscience, Volume 16, Number 6, Pages 639-652. https://doi.org/10.1080/17470919.2021.1997799. [PDF]

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In a special methods paper, we offer a guide on parent-child fNIRS hyperscanning data analysis in MATLAB and R. We provide a freely available exemplary dataset of 20 dyads (randomly sampled from the M-CARE participant pool), as well as MATLAB and R scripts to analyse the data.

With this guide, we hope to offer advice for future parent-child fNIRS hyperscanning investigations and to enhance replicability within the field.

Nguyen, T., Hoehl, S., and Vrtička, P. (2021). A Guide to Parent-Child fNIRS Hyperscanning Data Analysis. Sensors, 21, 4075. https://doi.org/10.3390/s21124075. OPEN ACCESS.

Please also check this separate webpage that offers an introduction to fNIRS hyperscanning.

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In a first combined D- & M-CARE paper, we examined the links between parental reflective functioning, attachment and sensitivity in 115 parents of 5-to-6-year-old preschoolers. We derived parental reflective functioning from parental self-reports (parental reflective functioning questionnaire – PRFQ), parental sensitivity from behavioural observation during parent-child interaction and parental attachment from the Adult Attachment Interview.

Our results revealed significant relations between parental reflective functioning, attachment and sensitivity, and particularly highlighted the role of dismissing attachment for alterations in parenting on both cognitive and behavioral levels, i.e., decreases in specific components of parental reflective functioning and sensitivity. Interestingly, these patterns were largely comparable in mothers and fathers and consistent for parental sensitivity coded behaviourally and parental reflective functioning derived from the PRFQ. Exploratory mediation analyses further suggested that decreased parental reflective functioning partially mediated the relationship between parents’ dismissing attachment and decreased parental sensitivity. For prevention and intervention programs targeting parental sensitivity, the interplay between parental reflective functioning and parents’ own attachment history thus emerges as a key mechanism.

Kungl, M.*, Gabler, S.*, White, L. O., Spangler, G., Vrtička, P. (accepted). Precursors and effects of parental reflective functioning: Links to caregivers’ attachment representations and behavioral sensitivity. Child Psychiatry & Human Development. Preprint: https://psyarxiv.com/ma6qd/. *= These authors share first authorship.

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In the second combined D- & M-CARE paper, we examined the links between interpersonal neural synchrony (INS), parents’ and children’s attachment representations and behavioural synchrony.

It is a central tenet of attachment theory that individual differences in attachment representations organise behaviour during social interactions. Secure attachment representations also facilitate behavioural synchrony, a key component of adaptive parent-child interactions. Yet, the dynamic neural processes underlying these interactions and the potential role of attachment representations remain largely unknown. A growing body of research indicates that interpersonal neural synchrony (INS) could be a potential neurobiological correlate of high interaction and relationship quality.

In this study, we examined whether interpersonal neural and behavioral synchrony during parent-child interaction are associated with parent and child attachment representations. In total, 140 parents (74 mothers and 66 fathers) and their offspring (age 5-6 years; 60 girls and 80 boys) engaged in cooperative versus individual problem-solving. INS in frontal and temporal regions was assessed with functional near-infrared spectroscopy (fNIRS) hyperscanning. Attachment representations were ascertained by means of the Adult Attachment Interview in parents and a story-completion task in children, alongside video-coded behavioural synchrony.

Findings revealed increased INS during cooperative versus individual problem solving across all dyads and topographic differences pertaining to parental biological sex. Remarkably, individual differences in attachment representations coincided with INS within frontal regions among mother-child dyads, but INS within temporal regions among daughter-parent dyads. Attachment representations were not associated with behavioural synchrony.

Our data thus provide further indication for INS as a promising correlate to probe the neurobiological underpinnings of attachment representations in the context of early parent-child interactions.

The paper is now published in Developmental Science: Nguyen, T.*, Kungl, M.*, Hoehl, S., White, L. O.^§, Vrtička, P.^§ (published online 24 March 2024). Visualizing the Invisible Tie: Linking Parent-Child Neural Synchrony to Parents’ and Children’s Attachment Representations. Developmental Science. *= These authors share first authorship. §= These authors share last authorship. https://doi.org/10.1111/desc.13504. OPEN ACCESS.

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Output: Preprints

In the third combined D- & M-CARE paper, we examined brain responses during a virtual ball-tossing game “Cyberball” that parents played with their own and an unrelated child.

Parents and children often engage in joint play – a domain where mothers and fathers are thought to exhibit disparate behaviors and impact child development via distinct pathways. However, little is known about the neural substrates of mother-child and father-child play. In this fMRI study, we sampled brain activation of parents of pre-schoolers (N=88) during a novel event-related adaptation of the virtual ball-tossing game “Cyberball”. Mothers (N=40) and fathers (N=48) played “Cyberball” ostensibly with their own and an unrelated child, who consecutively included, excluded, and re-included parents.

We found that overall, exclusion yielded comparable neural activation in mothers and fathers associated with mentalising, saliency, and emotion-processing. We also observed a parent gender effect in several brain areas: While mothers exhibited increased reward- and attention-related activity during inclusion, fathers displayed increased mentalising-related activity during exclusion. Additionally, we tested parents’ response to re-inclusion, which revealed a selective decrease in reward-related activity. There were no differences in parental brain activity as a function of child identity (own vs. unrelated).

This study elucidates the common and distinct means by which mothers and fathers engage with their children, especially during play, lending support for theories postulating partial differentiation of paternal and maternal parenting systems.

The paper is currently under peer-review but already available as a preprint: Acil, D., Puhlmann, L., White, L., and Vrtička, P. (under review). Caregiver and Playmate? Mothers’ and fathers’ brain responses to ball-play with their child – https://osf.io/preprints/psyarxiv/xpk8z.

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Output: Talks & Presentations

For more talks & presentations, please also see Dr Pascal Vrticka’s overall Talks & Presentations page.

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More information about the CARE, D-CARE, and M-CARE studies – particularly results and their discussion – will be posted here once it becomes available.