Perry, A, Mankuta, D and Shamay-Tsoory, S G (2015), OT promotes closer interpersonal distance among highly empathic individuals. Social, Cognitive and Affective Neuroscience, 10(1): 3–9

The study by Anat Perry, David Mankuta, and Simone G. Shamay-Tsoory investigated how Oxytocin (OT) affects interpersonal distance preferences in relation to empathic abilities.

Psychology Being Investigated

Interpersonal Distance – This refers to the physical space between people during interactions. It’s a crucial aspect of social behaviour, signalling comfort and responsiveness. People typically have an implicit sense of comfortable interpersonal distance, and variations in this distance can affect social interactions significantly​​​​.

Role of Oxytocin (OT) in Social Interactions – Oxytocin is a hormone that plays a significant role in social behaviours. The study explores how OT might alter the perceptual salience of social cues, impacting how individuals process these cues based on their empathic abilities​​.

Empathy and Social Behaviour – Empathy, the ability to understand and share the feelings of others, is crucial in shaping social behaviour. The study examines how varying levels of empathy might influence individuals’ responses to social cues, particularly in the context of interpersonal distance​​.

Background

Interpersonal Distance in Social Interactions – Prior studies highlighted that interpersonal distance — the space between people — plays a crucial role in shaping the dynamics of social interactions. This distance serves as an important cue signalling comfort and responsiveness in social settings. It’s an implicit yet clearly felt aspect, particularly noticeable when someone stands closer or farther away than culturally or socially expected​​.

Oxytocin’s Role in Social Behaviour – There has been increasing evidence suggesting that OT functions as a social hormone in humans. One of its significant roles appears to be altering the perceptual salience of social cues, which includes cues related to interpersonal distance. This finding implies that OT can influence how individuals perceive and respond to social interactions and cues​​.

Empathic Ability and Social Stimuli Processing – Prior research also suggested that an individual’s ability to empathize — to understand and share the feelings of others — might shape how they process social stimuli. This includes how individuals perceive and react to interpersonal distance in social interactions. It was theorised that OT could have varying effects on preferred interpersonal distances, depending on individual differences in empathy levels

Aims

The study aimed to examine how OT administration influences interpersonal distance preferences in individuals with varying levels of empathy. It hypothesised that OT would decrease preferred interpersonal distances among highly empathic individuals but increase them for less empathic ones​​.

Procedure and Methodology

Participants – 54 male undergraduate students aged 19-32 participated, divided into high and low empathy groups based on the Interpersonal Reactivity Index (IRI) scores.

Design – The study used a double-blind, placebo-controlled design. Participants attended two sessions a week apart, receiving either OT or a placebo.

Method – After administering OT/placebo, participants completed the IRI questionnaire. Two experiments followed.

First Experiment (Comfortable Interpersonal Distance Paradigm) – In this experiment, known as the Comfortable Interpersonal Distance (CID) paradigm, participants interacted with a computer-visualised protagonist. The protagonist would approach the participant in a computer-simulated room. Participants were instructed to indicate when they wanted the protagonist to stop, choosing a distance at which they felt most comfortable. This experiment has been previously validated and tested across different sex and age groups and with various types of protagonists.

Second Experiment (Intimacy Context) – This experiment focused on interpersonal distance preferences in the context of intimacy. Participants were asked to choose from several computer-visualised rooms where they would prefer to sit and discuss intimate topics with another participant. This was an original paradigm, previously tested in the lab, and shown to significantly predict Comfortable Interpersonal Distance scores.

Both experiments were designed to investigate how OT administration would affect interpersonal distance preferences among participants with varying levels of empathy. The hypothesis was that OT would promote closeness among highly empathic participants but might have an opposite effect on those with low empathic traits​​.

Variables – The study measured the effects of OT (treatment), empathy (between-subject factor), and conditions (within-subject factors) on interpersonal distance preferences​​.

Results

Experiment 1 (CID) – A significant main effect was found for the condition, with participants preferring different distances from the various protagonists (stranger, authority figure, friend, and ball). This effect suggests that perceived threat from others is a significant factor in mediating the equilibrium between interpersonal distance and social interaction​​.

Experiment 2 (Intimacy Context) – A significant effect was found for the condition, but no main effect for treatment and no significant second-order interactions. However, there was a significant third-order interaction between condition, treatment, and empathy. Specifically, the treatment x empathy interaction was significant only for the chairs condition. Participants in the high empathy group chose closer chair distances following OT administration, while the opposite was true for those in the low empathy group​​.

Overall Findings – The study concluded that administering OT had an impact on interpersonal distance preferences depending on the trait empathy levels of the participants. Participants with high empathy traits preferred closer interpersonal distances following OT administration, whereas an opposite trend was revealed among participants with low empathy traits​​.

These results indicate that the effect of OT on social cognition and behavior varies based on individual differences, such as empathy levels. The findings support the social salience hypothesis and highlight the nuanced role of OT in influencing social interactions.

Conclusions

The study concluded that Oxytocin (OT), a hormone, affects how close we want to be to other people, and this effect changes depending on how empathetic we are.

If someone is very empathetic, OT makes them comfortable with being closer to others. But if someone is not very empathetic, OT might make them want to keep more distance.

Therefore, OT doesn’t just make everyone friendlier or want to be closer; its effect varies from person to person based on their empathy levels.


Strengths

  • High internal validity – The double-blind, placebo-controlled design is the gold standard for clinical research. In this study, neither the participants nor the experimenters knew whether OT or a placebo was administered, which significantly reduced biases. This approach ensured that the effects observed could be more confidently attributed to OT, rather than the expectations or preconceptions of the participants or researchers.
  • Control of extraneous variables – The use of a computerised version of the CID task and a carefully designed room choice experiment provided precise and objective measures of interpersonal distance preferences. By standardizing the experimental conditions and ensuring that all participants were exposed to the same stimuli in a controlled environment, the study minimised external variables that could otherwise confound the results. This methodological precision enhances the credibility of the findings.
  • Reliability – The study’s design, which included two different but thematically related experiments (CID and Choosing Rooms), provided an opportunity to test the consistency of findings across different methodologies. The replication of similar results across these two distinct experimental setups significantly enhances the reliability of the findings. In research, the ability to replicate results under different conditions is a key indicator of their reliability.

Weaknesses

  • Marginal significance of results – The study found that the interaction between treatment (OT administration) and empathy was only marginally significant in the CID experiment (P = 0.09). This marginal significance indicates that the effects, while present, are not robustly demonstrated. In scientific research, especially in psychology, stronger statistical significance is generally sought to confidently assert findings.
  • Limited generalisability – The study included only male participants, significantly limiting its generalisability. The hormonal, psychological, and social dynamics can differ markedly between genders. Consequently, the study’s findings cannot be extrapolated to females, who may respond differently to OT in terms of interpersonal distance preferences.
  • Reduced ecological validity – The use of computerised experiments, while advantageous for standardisation and control of experimental conditions, may reduce ecological validity. The simulated nature of the tasks might not accurately capture the nuances of real-life social interactions where interpersonal distances are negotiated.