Multiple imitation mechanisms in children

Four studies using a computerized paradigm investigated whether children's imitation performance is content-specific and to what extent dependent on other cognitive processes such as trial-and-error learning, recall, and observational learning. Experiment 1 showed that 3-year-olds could successfully imitate what we call novel cognitive rules (e.g., first → second → third), which involved responding to 3 different pictures whose spatial configuration varied randomly from trial to trial. However, these same children failed to imitate what we call novel motor-spatial rules (e.g., up → down → right), which involved responding to 3 identical pictures that remained in a fixed spatial configuration from trial to trial. Experiment 2 showed that this dissociation was not due to a general difficulty in encoding motor-spatial content, as children successfully recalled, following a 30-s delay, a new motor-spatial sequence that had been learned by trial and error. Experiment 3 replicated these results and further demonstrated that 3-year-olds can infer a novel motor-spatial sequence following observation of a partially correct and partially incorrect response-a dissociation between imitation and observational learning (or emulation learning). Finally, Experiment 4 presented 3-year-olds with "familiar" motor-spatial sequences that involved making a linear response (e.g., left → middle → right) as well as "novel" motor-spatial sequences (e.g., right → up → down) used in Experiments 1-3 that were nonlinear and always involved a change in direction. Children had no difficulty imitating familiar motor-spatial sequences but again failed to imitate novel motor-spatial sequences. These results suggest that there may be multiple, dissociable imitation learning mechanisms that are content-specific. More importantly, the development of these imitation systems appears to be independent of the operations of other cognitive systems, including trial and error learning, recall, and observational learning.     

Imitation of body postures and hand movements in children with specific language impairment

Within the domain-general theory of language impairment, this study examined body posture and hand movement imitation in children with specific language impairment (SLI) and in their age-matched peers. Participants included 40 children with SLI (5 years 3 months to 6 years 10 months of age) and 40 children with typical language development (5 years 3 months to 6 years 7 months of age). Five tests were used to examine imitation and its underlying cognitive and motor skills such as kinesthesia, working memory, and gross motor coordination. It was hypothesized that children with SLI show a weakness in imitation of body postures and that this deficit is not equally influenced by the underlying cognitive and motor skills. There was a group effect in each cognitive and motor task, but only gross motor coordination proved to be a strong predictor of imitation in children with SLI. In contrast, hand movement imitation was strongly predicted by performance in the Kinesthesia task in typically developing children. Thus, the findings show not only that children with SLI performed more poorly on the imitation tasks than their typically developing peers but also that the groups’ performances showed qualitative differences. The results of the current study provide additional support to the view that the weaknesses in children with SLI are not limited to the verbal domain.     

Perceptual and cognitive processes in time-to-contact estimation: Analysis of prediction-motion and relative judgment tasks

Three classes of task appear to involve time-to-contact (TTC) information: coincidence anticipation (CA) tasks, relative judgment (RJ) tasks, and interceptive actions (IAs). An important type of CA task used to study the perception of TTC is the prediction-motion (PM) task. The question of whether it is possible to study the perceptual processes involved in the timing of IAs using PM and RJ tasks is considered. A revised version of the tau hypothesis is proposed as an account of the perceptual information processing involved in the control of fast IAs. This draws on the distinction between “motor” and “cognitive” visual systems. It is argued that task variables affect whether “cognitive” information processing is involved in performance and can determine whether TTC information is used at all. Evidence is reviewed that suggests that PM and RJ tasks involve cognitive processing. It is argued that target viewing time, TTC at response initiation, amount of practice, and whether there is a period between target disappearance and response are task variables that determine whether cognitive processing will influence responding.     

Becoming a high‐fidelity – super – imitator: what are the contributions of social and individual learning?

In contrast to other primates, human children's imitation performance goes from low to high fidelity soon after infancy. Are such changes associated with the development of other forms of learning? We addressed this question by testing 215 children (26–59 months) on two social conditions (imitation, emulation) – involving a demonstration – and two asocial conditions (trial‐and‐error, recall) – involving individual learning – using two touchscreen tasks. The tasks required responding to either three different pictures in a specific picture order (Cognitive: Airplane→Ball→Cow) or three identical pictures in a specific spatial order (Motor‐Spatial: Up→Down→Right). There were age‐related improvements across all conditions and imitation, emulation and recall performance were significantly better than trial‐and‐error learning. Generalized linear models demonstrated that motor‐spatial imitation fidelity was associated with age and motor‐spatial emulation performance, but cognitive imitation fidelity was only associated with age. While this study provides evidence for multiple imitation mechanisms, the development of one of those mechanisms – motor‐spatial imitation – may be bootstrapped by the development of another social learning skill – motor‐spatial emulation. Together, these findings provide important clues about the development of imitation, which is arguably a distinctive feature of the human species.     

Imitation of causally opaque versus causally transparent tool use by 3- and 5-year-old children

We investigated whether the tendency to imitate or emulate is influenced by the availability of causal information, and the amount of information available in a display. Three and 5-year-old children were shown by either a live or video model how to obtain a reward from either a clear or an opaque puzzle box. Some of the actions in the sequence were causally relevant to retrieving the reward, whereas others were irrelevant. The clear box made the causally irrelevant actions visible, whereas the opaque box prevented them from being seen. Results indicated that both 3- and 5-year-old children imitated the irrelevant actions regardless of the availability of causal information following a live demonstration. In contrast, the 3-year-olds employed an emulative approach, omitting irrelevant actions, when the information available was degraded in a video demonstration. However, the 5-year-olds were unaffected by the degraded information and employed an imitative approach. We suggest that imitation develops to be such an adaptive human strategy that it may often be employed at the expense of task efficiency.     

Kinematic Measures of Imitation Fidelity in Primary School Children

We sought to develop a method for measuring imitation accuracy objectively in primary school children. Children imitated a model drawing shapes on the same computer-tablet interface they saw used in video clips, allowing kinematics of model and observers' actions to be directly compared. Imitation accuracy was reported as a correlation reflecting the statistical dependency between values of the model's and participant's sets of actions, or as a mean absolute difference between them. Children showed consistent improvement in imitation accuracy across middle childhood. They appeared to rationalize the demands of the task by remembering duration and size of action, which enabled them to reenact speed through motor-planning mechanisms. Kinematic measures may provide a window into the cognitive mechanisms involved in imitation.     

Development of comprehension of sentences with “because” or “if”

The comprehension of sentences with “because” or “if” was investigated in children aged 2;9–11;11. Imitation, comprehension (choosing one of two picture sequences to go with a sentence), recognition (judging sentences with connective or structure differences as heard before or not), and synonymy (judging equivalence of meaning in sentences with different connectives or structures) tasks were administered, along with logical ordering, reversibility, and classification tasks. Above-chance responding in the comprehension task occurred by age 8, and in recognition and synonymy by age 10. Cognitive performance predicted 28.4% of the variance in the linguistic scores and cognitive success was concurrent with or preceded linguistic success. Comprehension of “because” and “if” appears to develop gradually, and is related to the development of certain operative rules.     

PRODUCING GENERATIVE SENTENCE USAGE BY IMITATION AND REINFORCEMENT PROCEDURES1

Three retarded subjects and two developmentally normal toddlers were trained using imitation and reinforcement procedures to use correct sentences. The experimental task was to use sentences with correct subject-verb agreement to describe pictures that were presented to the subjects. Two classes of sentences were taught: those involving a plural subject that required the use of the verb “are” (for example, “the boys are running”) and those involving a singular subject that required the use of the verb “is” (for example, “the boy is running”). The basic design of the study involved multiple baselines for each class of sentences. Four of the subjects began to produce novel, untrained sentences of a particular type to generalization probe pictures when that particular class of sentence was currently being trained. Thus, the imitation and reinforcement procedures appeared to be functional in producing generative sentence usage for both types of sentences. One subject produced correct sentences to both singular and plural probe pictures when only “is” sentences had been taught. A reversal procedure and retraining phase indicated that for this subject, imitation and reinforcement procedures for training one class of sentence behavior seemed functional in producing generative responses of the other class of sentences.     

Imitation of Self-Stimulation:

Three autistic children participated in single subject, reversal designs to compare the impact of over correction and adult imitation on self-stimulation. In addition to continuous 10-second observations of frequency of self-stimulation during 10 minute sessions, experimenter and observer also rated the child's mood, attention to the experimenter and quality of attention paid. The order of interventions was randomized fro each subject with baseline preceding each intervention. Although each child's response pattern was unique, the data showed systematic changes in rates of self-stimulation across conditions for two of the children with mean levels of self-stimulation declining during the over correction procedure and increasing during imitation. There were parallel changes in mood and attention with all three children appearing “happiest” and most attentive when their self-stimulatory behavior was imitated by the adult. These results raise interesting possibilities for using adult imitation as a vehicle for establishing a reinforcing relationship with the autistic child.     

SELF-STIMULATION AND LEARNING IN AUTISTIC CHILDREN: PHYSICAL OR FUNCTIONAL INCOMPATIBILITY?1

This study investigated whether an observed inverse relationship between self-stimulation and learning in autistic children is due to a physical inability of the subject to use the same body part for self-stimulation and task responding, or whether self-stimulation “distracts” the subject from task responding. Four actively self-stimulating autistic children were taught two discrimination tasks; one required a response that physically interferred with their self-stimulation; the other did not. Results were: (a) all subjects responded similarly across both tasks; (b) the three subjects with higher mental age scores learned both tasks without external suppression of self-stimulation; and (c) none of the subjects showed an inverse relationship between self-stimulation and learning. The study demonstrated that elimination of self-stimulation is not a necessary prerequisite for the acquisition of a new behavior in all autistic children.     

Imitation and representational development in young children with Down syndrome

Competence in object search and pretend play are argued to reflect young children's representational abilities and appear delayed in children with Down syndrome relative to social and imitative skills. This paper explores the effects on object search and play of this social strength in children with Down syndrome. Three experiments compared performance on traditional tasks with modified tasks designed to assess the role of imitation in object search and pretend play. Children with Down syndrome, relative to typically‐developing children, were able and willing to imitate hiding actions when no object was hidden (Experiment 1). When imitation was prevented in object search, children with Down syndrome searched less effectively than typically‐developing children (Experiment 2). In play, children with Down syndrome expressed more willingness to imitate a counter‐functional action, modelled by the experimenter, despite apparent competence in spontaneous functional play (Experiment 3). These findings indicate that object search and play behaviours of children with Down syndrome rely more heavily on imitation than is the case for typically‐developing children. The implications for the development of children with Down syndrome and models of representational development are discussed.     

认知操作背景下在线元认知调节能力的特征

利用认知任务为载体,对在线元认知调节特征进行研究,探讨了在线元认知调节的跨任务一致性和规则特异性。实验采用字母记忆与跟踪击键两种任务作为在线元认知调节的载体,通过逐步增加“提示线索”,观测个体在任务作业上的“成绩”（字母作业任务）或“成绩提高量”（跟踪击键任务）,以此作为评价在线元认知调节能力的指标。结果发现,随着认知任务中潜在规律线索数量的增加,被试能够通过在线元认知调节过程提高其认知作业水平;被试通过认知任务与追述报告分别反映的在线元认知调节水平具有一致性;在线元认知调节一方面具有跨任务情境的一致性,另一方面具有规则发现的差异性。因此,基于认知操作为背景的元认知评价方法能够较好地评估在线元认知调节能力     

The impact of task difficulty expectations on intrinsic motivation

Two studies investigated expectations of task difficulty induced prior to task involvement and their impact upon an individual's subsequent intrinsic interest. Expectations of task difficulty were manipulated through easy/hard instructions by the experimenters. Interest, but not performance, varied as function of expected task difficulty, with “easy” eliciting greater interest than “hard” instructions. The generality of this finding was supported by its demonstration in studies utilizing different experimenters (male, female), subject populations (children, college), and tasks (perceptual-motor, cognitive).     

Measuring procedural imitation aptitude in children: further validation of the Preschool Imitation and Praxis Scale (PIPS)

The Preschool Imitation and Praxis Scale (PIPS) was developed to measure bodily and procedural imitation aptitude in young children. However, the investigation of procedural imitation is more complex than that of bodily imitation. The procedural imitation tasks of the PIPS mainly consisted of unusual acts upon objects (for example, switching on a lamp in a toy animal with the forehead). This study assessed the suitability of these tasks by ruling out nonimitative learning in 15 typically developing children between 12 and 55 mo. of age (6 girls, 9 boys). Results indicated that the tasks seem novel and unlikely to be performed spontaneously by the children. In addition, the number of target acts performed by the children in the imitation condition was significantly higher than in the baseline, investigator-manipulation, and imitation-enhancement nonimitative control conditions. Finally, the tasks elicited more frequently imitative behaviour than end-state emulation. Therefore, the tasks appear appropriate to measure procedural imitation, and the findings support the theoretical validity of the PIPS.     

Gender Labels on Gender-Neutral Colors: Do they Affect Children’s Color Preferences and Play Performance?

Gender-typed color preferences are widely documented, and there has been increasing concern that they affect children’s play preferences. However, it is unclear whether such color preferences exist across cultures, how they have emerged, and how gender color-coding affects performance. Chinese preschoolers (n?=?126) aged 59 to 94 months were tested. First, we assessed their gender-typed color preferences using forced-choice tasks with color cards and pictures of neutral toys in gender-typed colors. Second, we tested if gender labels could affect color preferences by labeling two gender-neutral colors as gender-typed and assessed children’s liking for them using a rating task and a forced-choice task with pictures of neutral toys in the labeled colors. Third, we assigned children a tangram puzzle (i.e., a puzzle using geometric pieces) painted either in the gender-appropriate or gender-inappropriate color and measured the number of pieces they completed and their speed. Results showed that Chinese children exhibited the same gender-typed color preferences as Western children did. Moreover, applying gender labels amplified a gender difference in color preferences, thus providing direct and strong evidence for the social-cognitive pathway underlying gender-typed preferences. Finally, color-coding as gender-appropriate or -inappropriate had no impact on performance but the gender labels improved boys’ performance. These results add to knowledge on how gender-related information affects children’s responses to the social world and suggest that the current gender color divide should be reconsidered.     

Speed of processing, anticipation, inhibition and working memory in bilinguals

Literature on the so-called bilingual advantage is directed towards the investigation of whether the mastering of two languages fosters cognitive skills in the non-verbal domain. The present study aimed to evaluate whether the bilingual advantage in non-verbal skills could be best defined as domain-general or domain-specific, and, in the latter case, at identifying the basic cognitive skills involved. Bilingual and monolingual participants were divided into two different age groups (children, youths) and were tested on a battery of elementary cognitive tasks which included a choice reaction time task, a go/no-go task, two working memory tasks (numbers and symbols) and an anticipation task. Bilingual and monolingual children did not differ from each other except for the anticipation task, where bilinguals were found to be faster and more accurate than monolinguals. These findings suggest that anticipation, which has received little attention to date, is an important cognitive domain which needs to be evaluated to a greater extent both in bilingual and monolingual participants.     

Picture-word differences in decision latency: An analysis of single and dual memory models

Semantic and perceptual size decision times for pictorial and verbal material were analyzed in the context of a unitary memory model and several dual memory models. Experiment 1 involved a same-different categorical judgment task. The results showed that picture-picture response latencies were 185 msec faster than the corresponding word-word latencies, and word-picture and picture-word latencies equaled the mean of these two extremes. Similarity of subcategory for “same” judgments led to faster decision latency for all presentation conditions. Additionally, a linear relationship was found between picture-picture and word-word latencies for individual item pairs. Experiment 2 involved a comparison of pictures and words across a. categorical judgment and a size judgment task. Pictures produced faster decision latencies in both tasks, and the latency diflerence between pictures and words was comparable across tasks. These data fit the predictions of a unitary memory model. Several variants of a dual memory model are rejected and those which fit the data require assumptions about storage and/or transfer time values which result in a functional regression to the unitary memory model.     

Priming and binding in and across perception and action: A correlational analysis of the internal structure of event files

Individual performance was compared across three different tasks that tap into the binding of stimulus features in perception, the binding of action features in action planning, and the emergence of stimulus–response bindings (“event files”). Within a task correlations between the size of binding effects were found within visual perception (e.g., the strength of shape–location binding correlated positively with the strength of shape–colour binding) but not between perception and action planning, suggesting different, domain-specific binding mechanisms. To some degree, binding strength was predicted by priming effects of the respective features, especially if these features varied on a dimension that matched the current attentional set.     

Cultural transmission of irrelevant tool actions in diffusion chains of 3- and 5-year-old children

We used the diffusion chain method in order to investigate whether irrelevant actions would be transmitted along chains of 3- and 5-year-old children. Four chains of eight children witnessed a trained “expert” child perform a sequence of actions in order to retrieve a reward from either a transparent or an opaque puzzle box. The action sequence involved both goal relevant and goal irrelevant actions. In the transparent box chains the participants could potentially determine which of the actions were irrelevant as the causal effects were clearly visible. Results indicated that irrelevant actions transmitted down chains of 3-year-old children irrespective of box transparency. In contrast, irrelevant actions dropped out of the transparent box chain extremely quickly at 5 years, but were maintained within the opaque chain. These findings highlight the power of the diffusion chain method as a tool for exploring cultural learning.