Imitative Responses Research Articles

Perception and imitation of period-doubled phonation: Pitch and voice qualitya).

Period-doubled phonation, henceforth, period doubling, characterized by voicing periods that alternate in amplitudes and/or frequencies, is often perceived rough and with an indeterminate pitch. Lower pitch percept has been suggested by past studies when the degree of amplitude or frequency modulation increases. However, how listeners use period doubling when identifying linguistic tones remains unclear. The current study uses tasks of categorization with training, followed by imitation of tones manipulated with period doubling (with amplitude and frequency modulation, both separately and jointly) in a novel language. Native Mandarin and English speakers with different levels of music experience were tested. I show that period doubling leads to a low-tone bias in perception and imitation, especially as the modulation degree, particularly that of frequency, increases. Interestingly, interactions with stimulus f0 and modulation type show that in amplitude-modulated tokens, when compared to lower f0 (200 Hz), higher f0 (300 Hz) drives more low-tone responses. Period doubling is also imitated with lowered f0 and creaky quality. Language and music experience does not affect perceptual and imitative responses, suggesting that the perception of period doubling is not language-specific or conditioned by tonal knowledge. Period doubling likely signals low tones, even when the original f0 is high.

Automatic imitation is modulated by stimulus clarity but not by animacy

Observing actions evokes an automatic imitative response that activates mechanisms required to execute these actions. Automatic imitation is measured using the Stimulus Response Compatibility (SRC) task, which presents participants with compatible and incompatible prompt-distractor pairs. Automatic imitation, or the compatibility effect, is the difference in response times (RTs) between incompatible and compatible trials. Past results suggest that an action’s animacy affects automatic imitation: human-produced actions evoke larger effects than computer-generated actions. However, it appears that animacy effects occur mostly when non-human stimuli are less complex or less clear. Theoretical accounts make conflicting predictions regarding both stimulus manipulations. We conducted two SRC experiments that presented participants with an animacy manipulation (human and computer-generated stimuli, Experiment 1) and a clarity manipulation (stimuli with varying visual clarity using Gaussian blurring, Experiments 1 and 2) to tease apart effect of these manipulations. Participants in Experiment 1 responded slower for incompatible than for compatible trials, showing a compatibility effect. Experiment 1 found a null effect of animacy, but stimuli with lower visual clarity evoked smaller compatibility effects. Experiment 2 modulated clarity in five steps and reports decreasing compatibility effects for stimuli with lower clarity. Clarity, but not animacy, therefore affected automatic imitation, and theoretical implications and future directions are considered.

Using Prompting and Modeling to Teach Imitation Skills and Eye Contact to Syrian Children with Autism Spectrum Disorder

ABSTRACT Lack of eye contact and imitation deficits are frequently targeted in behavioral interventions for children with autism spectrum disorder (ASD). In this study, we examined the effects of prompting and modeling on the imitation skills and eye contact of three Arabic-speaking young children with ASD in Syria. A multiple baseline design with a withdrawal component was used to evaluate the effects of the intervention in a clinical setting, at a center for children with special needs, and in follow-up sessions conducted in the participants’ homes. All participants’ imitative responses and eye contact increased when prompting and modeling were used. Our findings support the effectiveness of prompting and modeling on imitation skills.

An active inference model of hierarchical action understanding, learning and imitation.

We advance a novel active inference model of the cognitive processing that underlies the acquisition of a hierarchical action repertoire and its use for observation, understanding and imitation. We illustrate the model in four simulations of a tennis learner who observes a teacher performing tennis shots, forms hierarchical representations of the observed actions, and imitates them. Our simulations show that the agent's oculomotor activity implements an active information sampling strategy that permits inferring the kinematic aspects of the observed movement, which lie at the lowest level of the action hierarchy. In turn, this low-level kinematic inference supports higher-level inferences about deeper aspects of the observed actions: proximal goals and intentions. Finally, the inferred action representations can steer imitative responses, but interfere with the execution of different actions. Our simulations show that hierarchical active inference provides a unified account of action observation, understanding, learning and imitation and helps explain the neurobiological underpinnings of visuomotor cognition, including the multiple routes for action understanding in the dorsal and ventral streams and mirror mechanisms.

Why We Mimic Emotions Even When No One is Watching: Limited Visual Contact and Emotional Mimicry

This article explores interpersonal functions of emotional mimicry under the absence versus the presence of visual contact between the interacting partners. We review relevant literature and stress that previous studies on the role of emotional mimicry were focused on imitative responses to facial displays. We also show that the rules explaining why people mimic facial expressions may be inapplicable when visual signals are unavailable (e.g., people attending an online meeting have their cameras off). Overall, our review suggests that emotional mimicry functionally adapts to whether the perceiver and the expresser can see each other. We, therefore, argue that blocking visual contact between them may provide insight into emotional mimicry's social functions, thereby clarifying its role in fostering affiliation and emotional understanding.

Automatic imitation of human and computer-generated vocal stimuli

Observing someone perform an action automatically activates neural substrates associated with executing that action. This covert response, or automatic imitation, is measured behaviourally using the stimulus–response compatibility (SRC) task. In an SRC task, participants are presented with compatible and incompatible response–distractor pairings (e.g., an instruction to say “ba” paired with an audio recording of “da” as an example of an incompatible trial). Automatic imitation is measured as the difference in response times (RT) or accuracy between incompatible and compatible trials. Larger automatic imitation effects have been interpreted as a larger covert imitation response. Past results suggest that an action’s biological status affects automatic imitation: Human-produced manual actions show enhanced automatic imitation effects compared with computer-generated actions. Per the integrated theory for language comprehension and production, action observation triggers a simulation process to recognize and interpret observed speech actions involving covert imitation. Human-generated actions are predicted to result in increased automatic imitation because the simulation process is predicted to engage more for actions produced by a speaker who is more similar to the listener. We conducted an online SRC task that presented participants with human and computer-generated speech stimuli to test this prediction. Participants responded faster to compatible than incompatible trials, showing an overall automatic imitation effect. Yet the human-generated and computer-generated vocal stimuli evoked similar automatic imitation effects. These results suggest that computer-generated speech stimuli evoke the same covert imitative response as human stimuli, thus rejecting predictions from the integrated theory of language comprehension and production.

Neural Marker of Habituation at 5 Months of Age Associated with Deferred Imitation Performance at 12 Months: A Longitudinal Study in the UK and The Gambia.

Across cultures, imitation provides a crucial route to learning during infancy. However, neural predictors which would enable early identification of infants at risk of suboptimal developmental outcomes are still rare. In this paper, we examine associations between ERP markers of habituation and novelty detection measured at 1 and 5 months of infant age in the UK (n = 61) and rural Gambia (n = 214) and infants’ responses on a deferred imitation task at 8 and 12 months. In both cohorts, habituation responses at 5 months significantly predicted deferred imitation responses at 12 months of age in both cohorts. Furthermore, ERP habituation responses explained a unique proportion of variance in deferred imitation scores which could not be accounted for by a neurobehavioural measure (Mullen Scales of Early Learning) conducted at 5 months of age. Our findings highlight the potential for ERP markers of habituation and novelty detection measured before 6 months of age to provide insight into later imitation abilities and memory development across diverse settings.

Market Dominance and Imitative Response to Product Proliferation: A Competitive Dynamics Perspective

Extant research theorizes that market leaders often use product proliferation to saturate product space thereby deterring rivals from introducing close substitutes. This study argues that this overlooks the diversity of market leaders. Market leaders run the gamut from firms with temporary leadership to firms that dominate their industry for decades. Consequently, the impact of product proliferation as an imitation barrier may not always be the same. In this paper we focus on product proliferation by dominant market leaders. Using competitive dynamics perspective, we argue that in competitive action-reaction context market followers will not desist from imitation, but instead imitate the market leaders in order to avoid falling behind in an evolving market. We test our predictions using data drawn from Indian automobile industry (2009-2019) which is consistently dominated by a dominant market leader: Suzuki Motors. We show that product proliferation by dominant firm in a given product submarket will result in imitative product proliferation response from rival firms. We also find that the imitative product proliferation by the rivals, as a response to the dominant firm’s product proliferation in a given product submarket, will result in performance gains for the imitating firms. Conversely, we do not find that when the dominant firm’s product proliferation occurs in a more complex product submarket then the likelihood of imitative product proliferation from the rival firms in this submarket will decrease, and similarly, we do not find that rivals’ imitative product proliferation in a complex product submarket will result in greater imitating firm performance.

Automatic imitation in youngsters with Gilles de la Tourette syndrome: A behavioral study

ABSTRACT It is widely known that humans have a tendency to imitate each other and that appropriate modulation of automatic imitative behaviors has a crucial function in social interactions. Gilles de la Tourette syndrome (GTS) is a childhood-onset neuropsychiatric disorder characterized by motor and phonic tics. Apart from tics, patients with GTS are often reported to show an abnormal tendency to automatically imitate others’ behaviors (i.e., echophenomena), which may be related to a failure in top-down inhibition of imitative response tendencies. The aim of the current study is to explore the top-down inhibitory mechanisms on automatic imitative behaviors in youngsters with GTS. Error rates and reaction times from 32 participants with GTS and 32 controls were collected in response to an automatic imitation task assessing the influence of observed movements displayed in the first-person perspective on congruent and incongruent motor responses. Results showed that participants with GTS had higher error rates than controls, and their responses were faster than those of controls in incompatible stimuli. Our findings provide novel evidence of a key difference between youngsters with GTS and typically developing participants in the ability to effectively control the production of own motor responses to sensory inputs deriving from observed actions.

Imitation in one's own presence: No specific effect of self-focus on imitation

Previous studies have reported that imitative responses may be modulated by top-down social factors such as self-focus. However, growing evidence suggests that such social factors may actually modulate domain-general processes such as spatially compatible responding, rather than specifically social processes such as imitation. In this study, we aimed to identify the cognitive processes being modulated under conditions of heightened or diminished self-focus. Participants performed a stimulus-response compatibility task which independently measures both spatial and imitative response tendencies, under two conditions: heightened self-focus, where the task was performed in the presence of two mirrors; and diminished self-focus, where the mirrors were covered. While participants were faster to respond to compatible trials than to incompatible trials, both imitatively and spatially, there was no significant modulation of either spatial or imitative compatibility by self-focus; although the magnitude of the modulation of spatial compatibility was numerically similar to the effect of self-focus on imitation found in previous studies. These results provide no evidence for an effect of self-focus on either social-specific, or domain-general, processes.

The Role of the Temporoparietal Junction in Self-Other Distinction.

Being able to discriminate between what originates from ourselves and what originates from others is critical for efficient interactions with our social environment. However, it remains an open question whether self-other distinction is a domain-general mechanism that is involved in various social-cognitive functions or whether specific 'self-other distinction mechanisms' exist for each of these functions. On the neural level, there is evidence that self-other distinction is related to a specific brain region at the border of the superior temporal and inferior parietal cortex, the temporoparietal junction (TPJ). Demonstrating that the TPJ plays a role in social processes that require self-other distinction would support the idea of a domain-general mechanism of self-other distinction. In the present paper, we review evidence coming from clinical observations, neuroimaging experiments and a meta-analysis indicating the involvement of the TPJ in various cognitive operations requiring self-other distinction. At the perceptual level, we discuss the human ability to identify one's own body and to distinguish it from others. At the action level, we review research on the human ability to experience agency and the control of imitative response tendencies. Finally, at the mental-state level, we discuss the ability to attribute mental states to others. Based on this integrative review, we suggest that the TPJ, and in particular its dorsal part, supports a domain general ability to enhance task-relevant representations when self-related and other-related representations are in conflict. Finally, this conception allows us to propose a unifying architecture for the emergence of numerous socio-cognitive abilities.

Neonatal imitation: Temporal characteristics in imitative response patterns

Neonatal imitation has been an area that has attracted intense attention within developmental psychology. Reported here are data from 33 newborn infants (16 girls; mean age: 47hr) assessed for imitation of tongue protrusion (TP) and mouth opening (MO). The stimuli were presented dynamically, in three 20-second-long gesture modeling intervals, interwoven with three 20-second-long intervals in which the presenter kept a passive face. Imitation of TP emerged among a majority of the infants during the first 60s of the experiment. In contrast, MO showed a protracted response and a majority exhibited imitation after 60s. The individual response pattern of the participating infants varied substantially over the course of the experiment. The study provides renewed support for neonatal imitation of MO and TP, and, in addition, suggests that the temporal organization of the responses observed is an important factor to consider, which in turn has methodological and theoretical implications.

Rational imitation declines within the second year of life: Changes in the function of imitation

Cultural learning plays a crucial role in enabling children to fit into their social community by mastering culture-specific habits. Infants learn actions via imitation, and they seem to be sensitive to the context in which a model demonstrates these. They imitate rationally by copying unusual means to achieve a goal more when the model chooses this means voluntarily compared with when some constraints force the model to do so. We investigated the development of rational imitation. In a within-participants design, 18-, 24-, and 36-month-olds (N = 293) observed two unusual actions: Instead of using her hands, a model operated an apparatus by using her head or by sitting on the apparatus. The model did so once with her hands being occupied and once with her hands being free. Besides measuring participants’ imitative responses, we analyzed the gaze behavior directed at the model during the response phase of the current study and of 14-month-olds (N = 82) from Gellén and Buttelmann’s study (Child Development Research, Vol. 2017, art. 8080649 [2017]). Increasing age was accompanied by an increasing rate of overall imitation across conditions. None of the three older age groups selectively imitated the unusual actions significantly more often in the hands-free condition than in the hands-occupied condition. Thus, rational imitation seems to disappear during the second year of life. Furthermore, there was a significant increase between 14 and 24 months of age and beyond in children’s tendency to gaze at the model after reenacting the observed action. Children’s gaze behavior indicates that this pattern might be due to a growing underlying social component in early cultural learning.

Clinical Application of a High-Probability Sequence to Promote Compliance with Vocal Imitation in a Child with Autism Spectrum Disorder.

The current study aimed to evaluate the effects of the high-probability (high-p) instructional procedure involving motor imitation on the levels of compliance with vocal imitation in a 3-year-old boy with autism spectrum disorder (ASD). We used a multiple-baseline design across three stimuli sets to demonstrate effects of the procedure over compliance with vocal imitation responses. Results demonstrated that the high-p procedural sequence was effective in increasing the levels of compliance with vocal imitation. We discuss these finding in terms of the operant mechanisms and clinical applications of increased compliance.

Motor simulation of multiple observed actions

Research has shown that observed actions are represented in the motor system, leading to automatic imitative responses. However, in social life, we often see multiple persons acting together. Here, we use an automatic imitation paradigm with four stimulus hands to investigate the hypothesis that multiple observed actions can be represented at the same time in the motor system. Experiments 1 and 2 revealed weaker automatic imitation when one hand performed a different action than the other three hands, compared with when three or four hands all performed the same action. Experiment 3 replicated this effect with mutually exclusive actions. These results show that multiple observed actions can be represented simultaneously in the motor system, even when they cannot be executed together. This has important implications for theories of interaction representation.

Automatic imitation of multiple agents: Simultaneous or random representation?

Research has shown that the observation of another's movement activates the corresponding motor representation in the observer. However, it is largely unknown how activation of these shared representations is influenced by the number of observed agents. In recent work, we have studied automatic imitation while participants saw 2 hands of which either one hand or both hands made a movement. These studies found that 2 hands produced a stronger imitative response than a single hand when the hands made an identical movement but not when they made different movements. It was argued that identical movements were mapped onto the same motor representation and therefore produced a stronger motor response. Nevertheless, an alternative explanation is that participants randomly represented 1 hand on each trial. The goal of the current study was to disentangle these 2 hypotheses. In Experiments 1 and 2, we replicate our results using a stimulus setup that made random sampling unlikely. In Experiment 3, we show that an additive effect was still present when attention was directed to 1 hand that always made a movement. Finally, in Experiment 4, we show that intentional imitation of 1 hand did not preclude automatic imitation of a second hand. Together, these findings support the hypothesis that the actions of multiple persons can be represented together in the motor system. (PsycINFO Database Record

The role of sensorimotor processes in social group contagion

Although it is well known that action observation triggers an imitative response, not much is known about how these responses develop as a function of group size. Research on social contagion suggests that imitative tendencies initially increase but then stabilize as groups become larger. However, these findings have mainly been explained in terms of interpretative processes. Across seven experiments (N = 322), the current study investigated the contribution of sensorimotor processes to social group contagion by looking at the relation between group size and automatic imitation in a task that involved minimal interpretation. The results of Experiments 1–2 revealed that automatic imitation increased with group size according to an asymptotic curve on congruent trials but a linear curve on incongruent trials. The results of Experiments 3–7 showed that the asymptote on congruent trials disappeared when no control was needed, namely in the absence of incongruent trials. This suggests that the asymptote in the relation between group size and automatic imitation can be explained in terms of strategic control mechanisms that aim to prevent unintended imitative responses. The findings of the current study are in close correspondence with previous research in the social domain and as such support the hypothesis that sensorimotor processes contribute to the relation between group size and social contagion.

Cultural dissimilarity: Boon or bane for technology diffusion?

The paper provides a theoretical model of technology adoption based on the idea that the diffusion of information about a technology depends both on the social structure of the adopters and their degree of assortativity. We propose a framework that - while retaining the core assumptions of epidemic diffusion models - allows for explicit modelling of the social structure via social network and of agents cultural heterogeneity via agent-based simulation. Decision-making takes place in institutional contexts where individual features trigger differentiated imitative responses and societal organization acts as medium on which information flows. The model simulates the diffusion of fertilizers in five Ethiopian villages (Peasant Associations), which differ in both political and relational structures and farmers belong to numerous ethnic and religious groups. Starting from survey data we run a compositional understanding simulation with the aim of reproducing observed diffusion curves on the basis of unobserved individual interactions. By minimizing the divergence from model output and observed diffusion, the exercise of categorical calibration and time series fit identify a set of plausible parameters for each village. Results highlight the importance of cultural dissimilarities to understand the diffusion processes.

Intentionally not imitating: Insula cortex engaged for top-down control of action mirroring

Perception and action are inextricably linked, down to the level of single cells which have both visual and motor response properties – dubbed ‘mirror neurons’. The mirror neuron system is generally associated with direct-matching or resonance between observed and executed actions (and goals). Yet in everyday interactions responding to another's movements with matching actions (or goals) is not always appropriate. Here we examine processes associated with intentionally not imitating, as separable from merely detecting an observed action as mismatching one's own. Using fMRI, we test how matched and mismatched stimulus-response mapping for actions is modulated depending on task-relevance. Participants were either cued to intentionally copy or oppose a presented action (intentional imitation or counter-imitation), or cued to perform a predefined action regardless of the presented action (incidental imitation or counter-imitation). We found distinct cortical networks underlying imitation compared to counter-imitation, involving areas typically associated with an action observation network and widespread occipital activation. Intentionally counter-imitating particularly involved frontal-parietal networks, including the insula and cingulate cortices. This task-dependent recruitment of frontal networks for the intentional selection of opposing responses supports previous evidence for the preparatory suppression of imitative responses. Sensorimotor mirroring is modulated via control processes, which complex human interactions often require.

P.1.f.004 - A study of mechanisms behind extreme aggression: the possible existence of functional signaling mechanisms modulated by ACTH IgG

Although it is well known that action observation triggers an imitative response, not much is known about how these responses develop as a function of group size. Research on social contagion suggests that imitative tendencies initially increase but then stabilize as groups become larger. However, these findings have mainly been explained in terms of interpretative processes. Across seven experiments (N = 322), the current study investigated the contribution of sensorimotor processes to social group contagion by looking at the relation between group size and automatic imitation in a task that involved minimal interpretation. The results of Experiments 1–2 revealed that automatic imitation increased with group size according to an asymptotic curve on congruent trials but a linear curve on incongruent trials. The results of Experiments 3–7 showed that the asymptote on congruent trials disappeared when no control was needed, namely in the absence of incongruent trials. This suggests that the asymptote in the relation between group size and automatic imitation can be explained in terms of strategic control mechanisms that aim to prevent unintended imitative responses. The findings of the current study are in close correspondence with previous research in the social domain and as such support the hypothesis that sensorimotor processes contribute to the relation between group size and social contagion.