The role of movement speed in learning a visuo-manual coordination in children

Summary The aim of the present study was to investigate the processes underlying aiming movements (motor programming and feedback control), and to explore their modification through learning. Two groups of 6- and 9-year-old children were asked to perform a directional aiming task without visual feedback (open-loop situation). After 15 trials (pretest) all subjects were submitted to a practice session which consisted of three series of trials with visual feedback (closed-loop situation). Half of the subjects had to perform the task at maximum speed (programmed movements), while the other half was required to perform slow movements (feedback-controlled movements). After the practice session all subjects were tested again in the openloop situation without time constraints (posttest). The results showed that during the practice session, accuracy was greater than in the two test conditions. It was greater in the case of slow movements than in the case of rapid ones. Moreover, in the case of rapid movements, it did not improve over the three practice series, while it did improve with slow movements. The difference between pre- and posttests showed that both groups improved their accuracy with practice in all conditions, the greatest improvement being obtained with rapid practice movements in 9-year-old children. It is suggested that different types of feedback (on-line and delayed feedback) contribute in varying degrees to the improvement of the aiming movements. However, the rapid movement condition, which requires a greater efficiency of programming, was found to be more effective for learning than the slow movement condition. The age-related differences found in learning suggest that feedback information can be fully integrated into motor programming only after 6 years of age.     

Evidence for a role of action in colour perception

Action is not usually considered to play a role in colour perception. However, sensorimotor theories of perception (eg O'Regan and No?, 2001 Behavior and Brain Science 24 939-1011) suggest that, on the contrary, the transformations created by action in the sensory input are a necessary condition for all perception. In the case of colour vision, eye movements may explain how a retina with significant irregularities in resolution and cone arrangement (Roorda and Williams, 1999 Nature 397 520-522) could permit the perception of a richly coloured world (Clark and O'Regan, 2000 15th International Conference on Pattern Recognition volume 2: Pattern Recognition and Neural Networks pp 503-506; Skaff et al, 2002 16th International Conference on Pattern Recognition volume 2, pp 681-684). We provide evidence that perception of colour is modified when an artificial coupling is introduced linking eye movements and colour changes. After 40 min of wearing left-field-blue/right-field-yellow spectacles, observers' colour vision adapts so that, after removing the spectacles, white patches seem to become bluer when the eyes move rightwards and yellower when the eyes move leftwards. This induced dependence of colour perception on the direction of eye saccade is shown to be related to the amount of eye movements during exposure. This result, which cannot be explained either by retinal adaptation, or by a conditioned association between colour and side, constitutes first clear evidence for a role of eye movements in perceived colour and argues for the involvement in colour perception of neural mechanisms continuously tuned to sensorimotor contingencies.     

The role of motor simulation in action perception: a neuropsychological case study

Research on embodied cognition stresses that bodily and motor processes constrain how we perceive others. Regarding action perception the most prominent hypothesis is that observed actions are matched to the observer’s own motor representations. Previous findings demonstrate that the motor laws that constrain one’s performance also constrain one’s perception of others’ actions. The present neuropsychological case study asked whether neurological impairments affect a person’s performance and action perception in the same way. The results showed that patient DS, who suffers from a frontal brain lesion, not only ignored target size when performing movements but also when asked to judge whether others can perform the same movements. In other words DS showed the same violation of Fitts’s law when performing and observing actions. These results further support the assumption of close perception action links and the assumption that these links recruit predictive mechanisms residing in the motor system.     

The role of proprioception in the perception and control of human movement: Toward a theoretical reassessment

The theoretical role of proprioception in the perception and control of human movement is elusive because of the obvious inability to manipulate experimentally the various receptive systems. Individuals who have had the metacarpophalangeal joint and joint capsule removed and replaced with silastic inserts afford a unique opportunity to evaluate a principal source of proprioception, namely, slowly adapting joint afferents. In a set of experiments, we show that such individuals show no deficits in finger localization following joint replacement. We take this and other complementary findings as a preliminary basis for proposing a dynamic rather than kinematic account of movement production. In addition, we provide a reconceptualization of the function of proprioceptive information in the CNS. Our arguments focus on proprioceptive inputs as tuning or modulating interneuronal pools rather than providing dimension-pecific information to the brain, as is commonly assumed.     

Dynamic object perception by pigeons: discrimination of action in video presentations

Two experiments examined the discrimination by pigeons of relative motion using computer-generated video stimuli. Using a go/no-go procedure, pigeons were tested with video stimuli in which the camera's perspective went either "around" or "through" an approaching object in a semi-realistic context. Experiment 1 found that pigeons could learn this discrimination and transfer it to videos composed from novel objects. Experiment 2 found that the order of the video's frames was critical to the discrimination of the videos. We hypothesize that the pigeons perceived a three-dimensional representation of the objects and the camera's relative motion and used this as the primary basis for discrimination. It is proposed that the pigeons might be able to form generalized natural categories for the different kinds of motions portrayed in the videos. Accepted after revision: 23 March 2001 Electronic Publication     

Perception-action coupling during bimanual coordination: the role of visual perception in the coalition of constraints that govern bimanual action

Constraints pertaining to interlimb coordination have been studied extensively in the past decades. In this debate, F. Mechsner (2004) has taken a provocative position by putting primary emphasis on perceptual principles that mediate coordinative stability. Whereas the present authors agree that the role of perceptual principles is of critical importance during coordination, they take issue with Mechsner's extreme position and with the evidence forwarded to support a purely perceptual-cognitive approach to bimanual coordination. More specifically, the authors emphasize that current knowledge about brain function argues against a dualism between perception and action, criticize the presented evidence that posture manipulations during coordination provide decisive evidence against motoric and muscular constraints, and report on potential pitfalls associated with the use of visual transformation procedures to support complex coordination patterns.     

The dynamics of perception and action

How might one account for the organization in behavior without attributing it to an internal control structure? The present article develops a theoretical framework called behavioral dynamics that integrates an information-based approach to perception with a dynamical systems approach to action. For a given task, the agent and its environment are treated as a pair of dynamical systems that are coupled mechanically and informationally. Their interactions give rise to the behavioral dynamics, a vector field with attractors that correspond to stable task solutions, repellers that correspond to avoided states, and bifurcations that correspond to behavioral transitions. The framework is used to develop theories of several tasks in which a human agent interacts with the physical environment, including bouncing a ball on a racquet, balancing an object, braking a vehicle, and guiding locomotion. Stable, adaptive behavior emerges from the dynamics of the interaction between a structured environment and an agent with simple control laws, under physical and informational constraints.     

Recognizing the role of perception in action at 6 months

The present research examined whether infants as young as 6 months of age would consider what objects a human agent could perceive when interpreting her actions on the objects. In two experiments, the infants took the agent's actions of repeatedly reaching for and grasping one of two possible objects as suggesting her preference for that object only when the agent could detect both objects, not when the agent's perceptual access to the second object was absent, either because a large screen hid the object from the agent ( Experiment 1 ), or because the agent sat with her back toward the object ( Experiment 2 ). These results suggest that young infants recognize the role of perception in constraining an agent's goal‐actions.     

The role of emotional context in facilitating imitative actions

In two experiments, we explored whether emotional context influences imitative action tendencies. To this end, we examined how emotional pictures, presented as primes, affect imitative tendencies using a compatibility paradigm. In Experiment 1, when seen index finger movements (lifting or tapping) and pre-instructed finger movements (tapping) were the same (tapping–tapping, compatible trials), participants were faster than when they were different (lifting–tapping, incompatible trials). This compatibility effect was enhanced when the seen finger movement was preceded by negative primes compared with positive or neutral primes. In Experiment 2, using only negative and neutral primes, the influence of negative primes on the compatibility effect was replicated with participants performing two types of pre-instructed finger movements (tapping and lifting). This emotional modulation of the compatibility effect was independent of the participants' trait anxiety level. Moreover, the emotional modulation pertained primarily to the compatible conditions, suggesting facilitated imitation due to negatively valent primes rather than increased interference. We speculate that negative stimuli increase imitative tendencies as a natural response in potential flight-or-fight situations.     

The role of movement and object in action memory: a comparative study between blind, blindfolded and sighted subjects

Two experiments systematically compared four SPT conditions involving real/imaginary movement and real/imaginary object with one VT condition involving no enactment and no object. To test the effect of visual information on SPT memory, sighted subjects were compared with blindfolded subjects (in Experiment 1) and blind subjects (in Experiment 2). All subjects learned all SPTs and VTs. Free recall data showed no difference between the SPT conditions and between the groups of subjects; only blind subjects were found to be limited in the use of visualization strategy. All SPTs were recalled better than VTs, indicating that the enactment effect is not determined by either movement or object alone, rather both have an effective role and are equally involved for obtaining the enactment effect. The results provide no support for the motor encoding and multimodality views of SPTs, but are in line with the episodic integration view which assumes that neither movement nor object are of special importance, rather both have contribution in the enactment effect.     

Central and peripheral coordination in movement sequences

Summary Motor coordination has been too poorly defined to be a useful construct in studying the control of movement. In general, motor coordination involves controlling both the timing and the kinematics of movement. Yet the motor behaviors typically used for the study of coordination have required controlling only the timing or the spatial aspects of a movement. To understand better the basis of motor behavior, this study examined movement sequences, a class of movement in which both the timing and the kinematics must be controlled. In one experiment we studied a reaching and grasping movement sequence to characterize the central coordination of movement sequences. In another experiment we studied a throwing movement sequence to characterize the peripheral (kinesthetic) coordination of movement sequences. An heuristic model is presented to explain how central and peripheral mechanisms of coordination might interact to produce accurate movement.     

Stratification in perception and action

Summary This paper discusses the concept of stratification, in the sense of levels of analysis and levels of control, in relation to human perception and performance. It is contended that functional analysis is the proper level of analysis for the domain of perception and action. This is illustrated by means of models of cognitive energetics and motor control. The functional level of analysis can be situated in between the level of symbolic representations and the level of neurophysiological mechanisms. It is also argued that the concept of levels of control provides a way of integrating or relating ecological and information-processing approaches to psychology, in the sense that ecological psychology is concerned with lower and more peripheral levels of control (coordinative structures). Finally, some remarks are made on the relation between cognition and perception and action, drawing on Piaget, and it is proposed that the concept of schema is more appropriate for the domain of perception and action than is the notion of symbolic representations.     

The subliminal perception of movement and the course of autokinesis

The course of autokinesis is shown to be sensitive to the real movement of a surrounding stimulus. With the supraliminal presentation of this stimulus, apparent movement in a direction opposite to that of the real movement is induced. With the subliminal presentation of the same stimulus the real movement serves to inhibit autokinesis by inducing brief periods of stationarity between the phases of upward and downward apparent movement. The results confirm previous findings that the movement of a stimulus may be discriminated without there being any perceptual (phenomenal) adjunct.     

The influence of action video game playing on eye movement behaviour during visual search in abstract,in-game and natural scenes

Action game playing has been associated with several improvements in visual attention tasks. However, it is not clear how such changes might influence the way we overtly select information from our visual world (i.e. eye movements). We examined whether action-video-game training changed eye movement behaviour in a series of visual search tasks including conjunctive search (relatively abstracted from natural behaviour), game-related search, and more naturalistic scene search. Forty nongamers were trained in either an action first-person shooter game or a card game (control) for 10 hours. As a further control, we recorded eye movements of 20 experienced action gamers on the same tasks. The results did not show any change in duration of fixations or saccade amplitude either from before to after the training or between all nongamers (pretraining) and experienced action gamers. However, we observed a change in search strategy, reflected by a reduction in the vertical distribution of fixations for the game-related search task in the action-game-trained group. This might suggest learning the likely distribution of targets. In other words, game training only skilled participants to search game images for targets important to the game, with no indication of transfer to the more natural scene search. Taken together, these results suggest no modification in overt allocation of attention. Either the skills that can be trained with action gaming are not powerful enough to influence information selection through eye movements, or action-game-learned skills are not used when deciding where to move the eyes.     

Anchoring in a novel bimanual coordination pattern

Anchoring in cyclical movements has been defined as regions of reduced spatial or temporal variability [Beek, P. J. (1989). Juggling dynamics. PhD thesis. Amsterdam: Free University Press] that are typically found at movement reversal points. For in-phase and anti-phase movements, synchronizing reversal points with a metronome pulse has resulted in decreased anchor point variability and increased pattern stability [Byblow, W. D., Carson, R. G., & Goodman, D. (1994). Expressions of asymmetries and anchoring in bimanual coordination. Human Movement Science, 13, 3-28; Fink, P. W., Foo, P., Jirsa, V. K., & Kelso, J. A. S. (2000). Local and global stabilization of coordination by sensory information. Experimental Brain Research, 134, 9-20]. The present experiment examined anchoring during acquisition, retention, and transfer of a 90 degrees phase-offset continuous bimanual coordination pattern (whereby the right limb lags the left limb by one quarter cycle), involving horizontal flexion about the elbow. Three metronome synchronization strategies were imposed: participants either synchronized maximal flexion of the right arm (i.e., single metronome), both flexion and extension of the right arm (i.e., double metronome within-limb), or flexion of each arm (i.e., double metronome between-limb) to an auditory metronome. In contrast to simpler in-phase and anti-phase movements, synchronization of additional reversal points to the metronome did not reduce reversal point variability or increase pattern stability. Furthermore, practicing under different metronome synchronization strategies did not appear to have a significant effect on the rate of acquisition of the pattern.     

The contextual action relationship between a tool and its action recipient modulates their joint perception

Facilitatory effects have been noted between tools and the objects that they act upon (their “action recipients”) across several paradigms. However, it has not been convincingly established that the motor system is directly involved in the joint visual processing of these object pairings. Here, we used the attentional blink (AB) paradigm to demonstrate privileged access to perceptual awareness for tool–action recipient object pairs and to investigate how motor affordances modulate their joint processing. We demonstrated a reduction in the size of the AB that was greater for congruent tool–action recipient pairings (e.g., hammer–nail) than for incongruent pairings (e.g., scissors–nail). Moreover, the AB was reduced only when action recipients followed their associated tool in the temporal sequence, but not when this order was reversed. Importantly, we also found that the effect was sensitive to manipulations of the motor congruence between the tool and the action recipient. First, we observed a greater reduction in the AB when the tool and action recipient were correctly aligned for action than when the tool was rotated to face away from the action recipient. Second, presenting a different tool as a distractor between the tool and action recipient target objects removed any benefit seen for congruent pairings. This was likely due to interference from the motor properties of the distractor tool that disrupted the motor synergy between the congruent tool and action recipient targets. Overall, these findings demonstrate that the contextual motoric relationship between tools and their action recipients facilitates their visual encoding and access to perceptual awareness.