Movers and shakers of cognition: Hand movements, speech, task properties, and variability

The interacting partner as the immediate environment: Personality, interpersonal dynamics, and bodily synchronization

OBJECTIVE

In social interactions, humans tend to naturally synchronize their body movements. We investigated interpersonal synchronization in conversations and examined its relationship with personality differences and post-interaction appraisals.

METHOD

In a 15-minute semi-structured conversation, 56 previously-unfamiliar dyads introduced themselves, followed by self-disclosing and argumentative conversations. Their bodily movements were video-recorded in a standardized room (112 young adults, aged 18-33, mean = 20.54, SD = 2.74; 58% Dutch, 31% German, 11% other). Interpersonal bodily synchronization was estimated as (a) synchronization strength using Windowed Lagged Cross-Correlations and (b) Dynamic Organization (Determinism/Entropy/Laminarity/Mean Line) using Cross-Recurrence Quantification Analysis. Bodily synchronization was associated with differences in Agreeableness and Extraversion (IPIP-NEO-120) and post-conversational appraisals (affect/closeness/enjoyment) in mixed-effect models.

RESULTS

Agreeable participants exhibited higher complexity in bodily synchronization dynamics (higher Entropy) than disagreeable individuals, who also reported more negative affect afterward. Interpersonal synchronization was stronger among extroverts than among introverts and extroverts appraised conversations as more positive and enjoyable. Bodily synchronization strength and dynamic organization were related to the type of conversation (self-disclosing/argumentative).

CONCLUSIONS

Interpersonal dynamics were intimately connected to differences in Agreeableness and Extraversion, varied across situations, and these parameters affected how pleasant, close, and enjoyable each conversation felt.

The dynamics of dyadic interactions between people of different ethnicities depend on their identification with all humanity

Individuals who have the disposition to identify with all humanity declare feeling close to people all over the world, caring about them, and perceiving them as an ingroup. However, never before were such declarations verified by measures of intergroup attitudes less direct than questionnaires, such as approach/avoidance tendencies or dynamical systems methods. Since individuals with higher dispositional identification with all humanity (IWAH) perceive people all over the world as ingroup members, we expected differences in the dynamic of inter-ethnic interactions (spatial distance, coordination, coupling, and leading), depending on a participant's level of IWAH. 227 participants fulfilled the IWAH scale, and those with the highest and lowest scores took part in a laboratory study, performing a task in inter-ethnic dyads. For the first time, an approach that combines a state-of-the-art tracking algorithm with a dynamical systems method was applied in such a context. Our results showed that those higher in IWAH kept a smaller distance from a partner, took a more leading role, and showed better coordination than those lower in IWAH. We found a similar trend for coupling. The results demonstrated the importance of IWAH for inter-ethnic relations and how it may shape non-verbal behaviors. Limitations are discussed.

Easier Said Than Done? Task Difficulty's Influence on Temporal Alignment, Semantic Similarity, and Complexity Matching Between Gestures and Speech

Gestures and speech are clearly synchronized in many ways. However, previous studies have shown that the semantic similarity between gestures and speech breaks down as people approach transitions in understanding. Explanations for these gesture–speech mismatches, which focus on gestures and speech expressing different cognitive strategies, have been criticized for disregarding gestures’ and speech's integration and synchronization. In the current study, we applied three different perspectives to investigate gesture–speech synchronization in an easy and a difficult task: temporal alignment, semantic similarity, and complexity matching. Participants engaged in a simple cognitive task and were assigned to either an easy or a difficult condition. We automatically measured pointing gestures, and we coded participant's speech, to determine the temporal alignment and semantic similarity between gestures and speech. Multifractal detrended fluctuation analysis was used to determine the extent of complexity matching between gestures and speech. We found that task difficulty indeed influenced gesture–speech synchronization in all three domains. We thereby extended the phenomenon of gesture–speech mismatches to difficult tasks in general. Furthermore, we investigated how temporal alignment, semantic similarity, and complexity matching were related in each condition, and how they predicted participants’ task performance. Our study illustrates how combining multiple perspectives, originating from different research areas (i.e., coordination dynamics, complexity science, cognitive psychology), provides novel understanding about cognitive concepts in general and about gesture–speech synchronization and task difficulty in particular.