Imitation: definitions, evidence, and mechanisms

Imitation can be defined as the copying of behavior. To a biologist, interest in imitation is focused on its adaptive value for the survival of the organism, but to a psychologist, the mechanisms responsible for imitation are the most interesting. For psychologists, the most important cases of imitation are those that involve demonstrated behavior that the imitator cannot see when it performs the behavior (e.g., scratching one's head). Such examples of imitation are sometimes referred to as opaque imitation because they are difficult to account for without positing cognitive mechanisms, such as perspective taking, that most animals have not been acknowledged to have. The present review first identifies various forms of social influence and social learning that do not qualify as opaque imitation, including species-typical mechanisms (e.g., mimicry and contagion), motivational mechanisms (e.g., social facilitation, incentive motivation, transfer of fear), attentional mechanisms (e.g., local enhancement, stimulus enhancement), imprinting, following, observational conditioning, and learning how the environment works (affordance learning). It then presents evidence for different forms of opaque imitation in animals, and identifies characteristics of human imitation that have been proposed to distinguish it from animal imitation. Finally, it examines the role played in opaque imitation by demonstrator reinforcement and observer motivation. Although accounts of imitation have been proposed that vary in their level of analysis from neural to cognitive, at present no theory of imitation appears to be adequate to account for the varied results that have been found.     

Coding of stimuli by animals: Retrospection, prospection, episodic memory and future planning

When animals code stimuli for later retrieval they can either code them in terms of the stimulus presented (as a retrospective memory) or in terms of the response or outcome anticipated (as a prospective memory). Although retrospective memory is typically assumed (as in the form of a memory trace), evidence of prospective coding has been found when response intentions and outcomes are particularly salient. At a more abstract level is the question of whether animals are able figuratively to travel back in time to recover memories of past events (episodic memory) and forward in time to predict future events (future planning). Although what would constitute adequate evidence of episodic memory and future planning is controversial, preliminary evidence suggests that animals may be capable of both forms of subjective time travel.     

Retrieval of names in face and object naming in an interference study

Two experiments using the interference paradigm are reported. In the first experiment, the participants spoke aloud the names of celebrities and the names of objects when presented with pictures while hearing distractors. In the case of proper names, we replicated the data obtained by Izaute and Bonin (2001) using the interference paradigm with a proper name written naming task. In the case of common names, the results replicated those obtained by Shriefers, Meyer, and Levelt (1990). In the second experiment, the participants produced the names of celebrities when presented with their faces while hearing distractors that were either proper names associated with the celebrities (associate condition), that belonged to a different professional category (different condition), or that corresponded to the proper names of the celebrities (identical condition). For negative SOAs, “associate” distractors were found to increase latencies compared to the “different category” condition. The implications of the findings for proper name retrieval are briefly discussed.     

Fostering Students’ Appraisals of the Relevance of History by Comparing Analogous Cases of an Enduring Human Issue: A Quasi-Experimental Study

To identify the challenges that students must meet to engage in effective self-directed inquiry, a class was followed for three years, from the fourth through the sixth grades, as they engaged in a sequence of progressively more demanding inquiry activities. Students made substantial progress in understanding the objectives of inquiry, identifying questions, attending to evidence, identifying patterns, making controlled comparisons, interpreting increasingly complex data, supporting claims, and drawing justified conclusions. Retaining awareness of inquiry objectives and integrating influences of multiple variables in predicting outcomes were two areas that remained challenging. A comparison group of seventh graders who had not been involved in the program displayed strikingly different approaches to an inquiry task, indicating that the skills identified here are not ones that develop in the absence of appropriate kinds of educational experiences.     

The “simulation” of the facial expression of emotions in case of short and long stimulus duration. The effect of pre-motor cortex inhibition by rTMS

Embodied cognition model states that the “simulation process” is necessary to the recognition of emotional significance of face. The present research explored the contribution of frontal motor brain components (i.e. mainly premotor area) to embodied cognition by using rTMS stimulation, to produce a temporary disruption of this specific cortical site. Secondly, short and long stimulus duration conditions were included to verify the contribution of the “simulation process” in response to overt and covert emotional stimulus comprehension. Nineteen subjects were asked to detect emotion/no emotion (anger, fear, happiness, neutral) in these two experimental conditions, by using a backward masking procedure. Five-second rTMS (1 Hz) was delivered before the stimulus onset. False alarms (Fa) and RTs increased and Hits decreased when frontal premotor brain activity was disrupted, specifically in response to anger and fear, for both long and shortduration condition. Thus, the present results highlight the main role of the frontal motor system for emotion facial expression processing.     

Mental rotation performance in primary school age children: Are there gender differences in chronometric tests?

In contrast to the well documented male advantage in psychometric mental rotation tests, gender differences in chronometric experimental designs are still under dispute. Therefore, a systematic investigation of gender differences in mental rotation performance in primary-school children is presented in this paper. A chronometric mental rotation task was used to test 449 second and fourth graders. The children were tested in three separate groups each with different stimulus material (animal drawings, letters, or cube figures). The results show that chronometric mental rotation tasks with cube figures – even rotated in picture plane only – were too difficult for children in both age groups. Further analyses with animal drawings and letters as stimuli revealed an overall gender difference in response time (RT) favoring males, an increasing RT with increasing angular disparity for all children, and faster RTs for fourth graders compared to second graders. This is the first study which has shown consistent gender differences in chronometric mental rotation with primary school aged children regarding reaction time and accuracy while considering appropriate stimuli.     

Can the irrelevant speech effect turn into a stimulus suffix effect?

The irrelevant sound effect (ISE) and the stimulus suffix effect (SSE) are two qualitatively different phenomena, although in both paradigms irrelevant auditory material is played while a verbal serial recall task is being performed. Jones, Macken, and Nicholls (2004) Jones, D. M., Macken, W. J. and Nicholls, A. P. 2004. The phonological store of working memory: Is it phonological and is it a store?. Journal of Experimental Psychology: Learning, Memory, and Cognition, 30: 656–674. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar] have proposed the effect of irrelevant speech on auditory serial recall to switch from an ISE to an SSE mechanism, if the auditory-perceptive similarity of relevant and irrelevant material is maximized. The experiment reported here (n = 36) tested this hypothesis by exploring auditory serial recall performance both under irrelevant speech and under speech suffix conditions. These speech materials were spoken either by the same voice as the auditory items to be recalled or by a different voice. The experimental conditions were such that the likelihood of obtaining an SSE was maximized. The results, however, show that irrelevant speech—in contrast to speech suffixes—affects auditory serial recall independently of its perceptive similarity to the items to be recalled and thus in terms of an ISE mechanism that crucially extends to recency. The ISE thus cannot turn into an SSE.     

Effects of visual cue and response assignment on spatial stimulus coding in stimulus–response compatibility

Tlauka and McKenna (2000 Tlauka, M. and McKenna, F. P. 2000. Hierarchical knowledge influences stimulus–response compatibility effects. Quarterly Journal of Experimental Psychology, 53A: 85–103.  [Google Scholar]) reported a reversal of the traditional stimulus–response compatibility (SRC) effect (faster responding to a stimulus presented on the same side than to one on the opposite side) when the stimulus appearing on one side of a display is a member of a superordinate unit that is largely on the opposite side. We investigated the effects of a visual cue that explicitly shows a superordinate unit, and of assignment of multiple stimuli within each superordinate unit to one response, on the SRC effect based on superordinate unit position. Three experiments revealed that stimulus–response assignment is critical, while the visual cue plays a minor role, in eliciting the SRC effect based on the superordinate unit position. Findings suggest bidirectional interaction between perception and action and simultaneous spatial stimulus coding according to multiple frames of reference, with contribution of each coding to the SRC effect flexibly varying with task situations.     

The role of stimulus preexposure in problem solving by Octopus vulgaris

Octopus vulgaris is able to open transparent glass jars closed with plastic plugs and containing live crabs. The decrease in performance times for removing the plug and seizing the prey with increasing experience of the task has been taken to indicate learning. However, octopuses’ attack behaviors are typically slow and variable in novel environmental situations. In this study the role of preexposure to selected features of the problem-solving context was investigated. Although octopuses failed to benefit from greater familiarity with the training context or with selected elements of the task of solving the jar problem, the methodological strategies used are instructive in potentially clarifying the role of complex problem-solving behaviors in this species including stimulus preexposure and social learning. Received: 27 April 1998 / Accepted after revision: 24 July 1998     

Stimulus–response correspondence effect as a function of temporal overlap between relevant and irrelevant information processing

The stimulus–response correspondence (SRC) effect refers to advantages in performance when stimulus and response correspond in dimensions or features, even if the common features are irrelevant to the task. Previous research indicated that the SRC effect depends on the temporal course of stimulus information processing. The current study investigated how the temporal overlap between relevant and irrelevant stimulus processing influences the SRC effect. In this experiment, the irrelevant stimulus (a previously associated tone) preceded the relevant stimulus (a coloured rectangle). The irrelevant and relevant stimuli onset asynchrony was varied to manipulate the temporal overlap between the irrelevant and relevant stimuli processing. Results indicated that the SRC effect size varied as a quadratic function of the temporal overlap between the relevant stimulus and irrelevant stimulus. This finding extends previous experimental observations that the SRC effect size varies in an increasing or decreasing function with reaction time. The current study demonstrated a quadratic function between effect size and the temporal overlap.