Attachment & Bio-Behavioural Synchrony in Dyads

Attachment & Bio-Behavioural Synchrony in Dyads


The field of social neuroscience is currently undergoing an important transition. Until recently, social cognitive and emotional processing were mostly investigated in single participants in isolation – e.g., by presenting social images, videos, sounds, etc., via screens to participants that are alone during fMRI or EEG data acquisition. This experimental approach is nowadays referred to as “1st person social neuroscience”. During the last years, the focus has increasingly shifted to measuring brain activation in two (or more) people during direct and live social interaction using so-called hyperscanning paradigms, thereby enabling “2nd person social neuroscience“.

During 2nd person social neuroscience investigations, neural signals are obtained from two (or more) participant individually and subsequently assessed for their temporal alignment or coherence, also called interpersonal neural synchrony. The same procedure can be applied for behavioural (e.g., eye gaze, touch), physiological (e.g., heart rate), and endocrine (e.g., secretion of oxytocin, cortisol) measures. This is summarised under the umbrella term bio-behavioural synchrony pioneered by Ruth Feldman. For a very nice recent overview of bio-behavioural synchrony in general, and within the context of parent- (and particularly mother-) child interaction, attachment, and caregiving more specifically, see here.

Bio-behavioural synchrony is a fundamental component of social interactions, and particularly important in early life. By attuning one’s physiological and emotional states, parents help co-regulating their children’s allostasis and thereby ensure children’s immediate survival. Bio-behavioural synchrony also plays a vital role for learning and socio-emotional and cognitive development. Bio-behavioural synchrony is most prominent within intimate / close emotional bonds and thus tightly linked to attachment and caregiving. The SoNeAt Lab is investigating bio-behavioural synchrony, and particularly its neural component of interpersonal neural synchrony, from an attachment perspective. Our 2nd person social neuroscience technique of choice to assess interpersonal neural synchrony is functional near-infrared spectroscopy (fNIRS) hyperscanning.

Relevant Talk Recordings & Articles

A 45-minute keynote about SoNeAt Lab’s fNIRS hyperscanning research in association with interindividual differences in attachment and caregiving between mums, dads and kids (“Are we on the same wavelength? Individual differences in interpersonal neural synchrony“) is available online (talk presented by Dr Pascal Vrticka on September 22, 2022 at the Affect, Personality and the Embodied Brain (APE) Meeting 2022).

A short 30-minute presentation of SoNeAt Lab’s fNIRS hyperscanning research investigating bio-behavioural synchrony, interpersonal neural synchrony, and attachment (“Bio-behavioural synchrony and inter-brain coherence: an attachment perspective“) is available as a YouTube video (talk by Dr Pascal Vrticka on June 13, 2020 at the virtual conference Neurosync 2020).

Another 45-minute overview of Social Neuroscience, outlining both 1st and 2nd person social neuroscience research performed within the SoNeAt Lab (“Social Neuroscience – From 1st to 2nd Person Paradigms“) is available to view here (talk by Dr Pascal Vrticka from March 18, 2021 at a virtual seminar for the Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea & Institute of Electrical and Electronics Engineers (IEEE), Gwangju Section, South Korea).

If you are interested in fNIRS hyperscanning, particularly within parent-child dyads, there now is a special methods paper available, in which we offer a detailed analysis guide. We also 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 AnalysisSensors (Section Biosensors; Special issue on “Brain Signals Acquisition and Processing”), 21, 4075. ACCESS.

Attachment & Bio-Behavioural Synchrony in Adult-Adult Dyads

In a project carried out at Stanford University, we are currently assessing bio-behavioural synchrony between (young) adult participants while they perform different collaborative, competitive, and independent versions of a reaction time task (for a previous publication using the same task, see here). Attachment in both players was measured with the self-report questionnaire Experiences in Close Relationships revised (ECR-R).

Furthermore, in a new project at the Max Plank Institute in Leipzig, in collaboration with the University of Erlangen-Nuremberg, we are looking at bio-behavioural synchrony in couples during stress, also including various attachment measures (self-reports and the Adult Attachment Interview).

More details will be described here once they become available.

Attachment & Bio-Behavioural Synchrony in Parent-Child Dyads

In a project at Stanford University, we looked at interpersonal neural synchrony in 8-13 year old children and their mothers. The corresponding paper is published in Neuropsychologia – see here and on the publications page. The background and results of this paper can also be further explored in one of the blog posts on this website and coverage by Science Trends. Attachment in children towards their mothers was measured using a child version of the self-report questionnaire Experiences in Close Relationships revised (ECR-RC).

In the context of our CARE studies, we are assessing bio-behavioural synchrony between 5-6 year-old children and their parents (both mothers and fathers) during a collaborative puzzle-solving task and free verbal conversation. Attachment is assessed by means of self-report questionnaires, narrative measures (Adult Attachment Interview and McArthur Story Stems), as well as behavioural coding.

A first paper on mother-child bio-behavioural synchrony during a collaborative puzzle-solving task is published in Cortex: 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 solvingCortex, Volume 124, Pages 235-249, OPEN ACCESS. For a summary, see the recent blog post.

A second paper on mother-child bio-behavioural synchrony during free verbal conversation is published in SCAN: Nguyen, T., Schleihauf, H., Kayhan, E., Matthes, D., Vrtička, P., Hoehl, S. (published online – June 15th 2020). Neural synchrony in mother-child conversation: Exploring the role of communicative featuresSocial Cognitive Affective Neuroscience ACCESS. More information is available here / for a summary, see the recent blog post.

A third paper on father-child bio-behavioural synchrony during a collaborative puzzle-solving task is available in Child Development: Nguyen, T., Schleihauf, H., Kungl, M., Kayhan, E., Hoehl, S., Vrtička, P. (in press – published online 10 January 2021). Interpersonal neurobehavioral synchrony during father-child problem solving: An fNIRS hyperscanning study. Child Development. *= these authors share senior authorship. OPEN ACCESS. More information is also available in the two press releases from the University of Essex (English) and University of Vienna (German).

A summary on “Synced brains: how to bond with your kids – according to neuroscience” is furthermore available via The Conversation UK.

Please note that there is an additional page on Dr Vrticka’s website specifically dedicated to Caring Dads: The Social Neuroscience of Attachment & Caregiving in Fathers.