Motor Schema Formation and Retention in Young Children

The variability-of-practice hypothesis, a major prediction of Schmidt’s (1975) motor schema theory, was tested in an attempt to investigate motor-schema formation. In addition, schema retention was observed after a 2-week retention interval. The task involved preschool children in tossing a bean bag for appropriate distance. Four treatment groups received 100 practice trials equally divided over five days. Variation was provided by varying the weights of the bean bags. The testing situations involved tossing a criterion weighted bean bag as well as a novel weighted bean bag which none of the groups had experienced previously. In addition, all groups were tested on a new but similar task. The results supported the variability-of-practice hypothesis in terms of schema formation and transfer to novel tasks in the same movement class. After a two-week retention interval, loss in performance was significantly less for the group with variability of practice than all other groups.     

The level of organization of the motor schema

The interpretations of Piaget and Schmidt on the level on which the motor schema is supposedly effective were evaluated in pre-school children of different ages in a throwing task. In an analysis of variance on the accuracy scores, significant main effects for age, sex, and throwing arm were found. Further, the results showed no relationship between accuracy scores with the preferred and non-preferred arm in the younger group, while in the older group a moderate relationship was found. This result was interpreted in terms of structural development and as a warning for studies where Schmidt's variability-of-practice hypothesis is tested.     

Practice variability and children's motor behavior

This research investigated Schmidt's variability-of-practice prediction and the breadth-of-a-movement class. Schmidt's hypothesis was tested by varying the parameters of ball and distance in overarm throwing. Breadth-of-a-movement class was tested by employing two novel tasks not previously used in variability-of-practice designs. 203 kindergarten and first-grade subjects were randomly assigned to one of four conditions, three experimental and one control. Experimental subjects performed 45 trials in their respective training conditions, weight, distance, weight/distance, in one session. Two novel striking tasks were administered to all subjects pre- and posttest to assess the variability-of-practice hypothesis, and the generalizability of overarm throwing and striking. Variability-of-practice in the overarm throw appeared to strengthen the striking schemas of the kindergarten boys. Results suggest some support for the inclusion of throwing and striking in a single-movement class. The concept, breadth of movement class, however, requires further study.     

Variability in practice: facilitation in retention and transfer through schema formation or context effects?

The main purpose of the study was to examine whether the effects of variability in practice within a class of movements, that is, enhanced retention and transfer performance relative to constant practice, are due to the formation of motor schemata (Schmidt, 1975) or to contextual interference effects, as suggested by Lee, Magill, and Weeks (1985). Forty-eight subjects were tested on a sequential timing task. One group of subjects (Schema) received variable practice within one movement class, practicing the same phasing pattern with different absolute durations. Practice conditions of another group (Context) involved the same absolute movement durations, as well as a different phasing pattern for each task version. Thus, contextual interference was about the same for both groups but only one group experienced different movement variations of the same class. On a retention test performed on a task version that had been practiced by both groups before as well as on a transfer test with the same phasing pattern but a longer absolute duration, the Schema group performed more effectively than the Context group, thus supporting schema theory. On a transfer task with new phasing requirements, however, the Context group demonstrated performance superior to that of the Schema group. In this case, the Context practice condition seemed to be more transfer-appropriate.     

Schema: the variability of practice hypothesis

An experiment is presented which tested the variability of practice hypothesis of Schmidt's (1975) schema theory. Children served as subjects and a complex motor task was used. The results supported the variability of practice hypothesis in that the group that had more variable practice did perform better on the average on a novel variation of the task than did the group with less variable practice. There was no support for the suggestion that variability of practice would increase the rate of improvement on the novel variation. The results are discussed in relation to the differential importance of the four subcomponents of the schema in its development.     

Variability of Practice and Contextual Interference in Motor Skill Learning

The purpose of this study was to investigate whether learning benefits in multiple-task learning situations are a result of contextual interference or of schema enhancement related to the amount of variability in the practice session. Two experiments were designed that replicated and extended the experiment reported by Wulf and Schmidt (1988). In a 2 (same vs. different relative time) x 2 (blocked vs. random practice schedule) design, 48 right-handed subjects were randomly assigned to one of four experimental conditions. A tapping task was employed that required a right-handed tap of three small brass plates arranged in a diamond pattern. Each segment had a specific time requirement. Target times and response times were provided on a computer screen directly in front of the subject. Each subject participated in two acquisition sessions (i.e., 198 practice trials) and was tested for learning on several different retention and transfer tests. In Experiment 2, a control group was added that received no acquisition phase. Results of both experiments showed a typical contextual interference effect, with depressed scores by the random groups during acquisition but significantly better scores than the blocked groups on several retention and transfer tests. Certain characteristics of the tests were found to influence the demonstration of the practice schedule effects. These results were consistent with predictions from Magill and Hall (1990) that the learning benefits of contextual interference are more likely to occur when skill variations are from different classes of movement and that the amount of variability in practice is more influential when the to-be-learned tasks are parameter modifications of the same generalized motor program.     

The utility of connectionism for motor learning: a reinterpretation of contextual interference in movement schemas

Using the general framework of schema theory, and building on it, the present article takes a connectionist approach to motor learning and to contextual interference effects. These phenomena were simulated in an exploratory manner in neural networks. The outcome closely reflects previous research with humans. In a simulated ballistic movement task, networks performed worse during practice but showed better transfer when target movement distances were presented in a random rather than a blocked fashion. Connectionism provides a parsimonious account of the effect in terms of properties inherent in the parallel distributed network.     

The Utility of Connectionism for Motor Learning: A Reinterpretation of Contextual Interference in Movement Schemas

Using the general framework of schema theory, and building on it, the present article takes a connectionist approach to motor learning and to contextual interference effects. These phenomena were simulated in an exploratory manner in neural networks. The outcome closely reflects previous research with humans. In a simulated ballistic movement task, networks performed worse during practice but showed better transfer when target movement distances were presented in a random rather than a blocked fashion. Connectionism provides a parsimonious account of the effect in terms of properties inherent in the parallel distributed network.     

Effects of variable practice on retention and motor schema development in Down syndrome subjects

Portions of Schmidt's schema theory, the effects of variable practice on retention and ability to learn a novel motor task, were tested using Down syndrome subjects. 23 subjects ranged in mental and chronological ages from 3.0 to 5.1 yr. and 4.6 to 22 yr., respectively. IQs ranged from 32 to 62. The two throwing tasks were closed, discrete movements requiring no feedback or error detection during movement. Subjects were randomly assigned to a specific-practice, variable-practice, or control group. Specific group subjects practiced 100 trials from the test-target location. Variable-practice subjects also practiced 100 trials but from four different practice locations. The control group practiced an unrelated kicking activity. All subjects participated in identical pretests, posttests, and retention tests to assess accuracy on these throwing tasks. A standard archery target was used to score tosses. To examine the effects of practice on a novel task, two target conditions, or tasks, were employed. On Task A the subject tossed a bean bag at the archery target placed flat on the floor. For Task B, the novel task, the target was placed upright on the wall. Subjects were assigned higher scores for tosses landing closer to the center of the target. Analysis of variance indicated no significant differences between groups on Task A pretest or posttest. Significance was detected for the main effect of group for Task B. However, the Scheffé post hoc test indicated that the simple main effects were nonsignificant. This research did not support Schmidt's schema theory.(ABSTRACT TRUNCATED AT 250 WORDS)     

Specific and varied practice of motor skill

To assess the potential effect of specific and varied practice on the development of motor schema, 64 children in two age groups (8 yr. and 12 yr.) were tested on a simple throwing task at the beginning and end of a 12-wk. physical education program. For the throwing test the children were assigned to either a specificity or a schema group (varied practice). The task was performed without visual feedback, but knowledge of results was given after each trial. Prior to both tests at the criterion target, the specific group was given practice throws using the criterion target distance, whereas the schema group practiced on two other targets. No differences were found between the two groups at the beginning of the program but on the posttest those children receiving a variety of practice on the throwing task performed significantly better than the specific-practice group. Thus it was suggested that a varied practice schedule may facilitate the initial formation of motor schema, and this process may be enhanced by participation in a physical education program.     

Development of movement schema in young children

To examine the development of movement schema in young school-age children, i.e., whether principles which govern fine eye-hand coordination skill learning as suggested by Schmidt's schema theory apply to the learning of gross motor skills Exp. 1 involved 48 right-handed first-grade children. On a modification of the Fitts Reciprocal Tapping task children moved a stylus (held in the hand or attached to a special shoe worn on the foot) between two metal targets separated by different distances. Children were randomly assigned to one of eight groups: two control or no-practice groups and six experimental or transfer groups. A one-way analysis of variance followed by appropriate Scheffé post hoc tests indicated that movements of the lower limbs were not organized into a movement schema, but a pattern of schema of movement for the upper limbs developed. That no movement schema developed for lower limb movements suggests development of movement schema is intricately linked to both the existing as well as the potential for developing precise movement in those limbs. Exp. 2 involved 40 first-grade children who were randomly assigned to perform a gross-motor agility task under one of three conditions: direct practice on the criterion task, constant practice on a modification of the criterion task, or variable practice on several different modifications of the criterion task. A groups X trials analysis of variance with appropriate post hoc tests indicated that there were no significant differences among direct, constant, or variable practice groups. Data suggest that the amount of practice may be as important as the type of practice in developing movement schema involved in gross motor skills in young children.     

Retroactive interference and mental practice effects on motor performance: a pilot study

This study examined the effect of similar versus dissimilar retroactive interference on the mental practice effects for performing a novel motor skill. Research has shown that mental practice of a motor task can interfere with learning and performance of the task; however, little is known about how different retroactive interference activities affect mental practice effects. 90 volunteers ages 18 to 51 years (M=26.8, SD=9.6) completed a pre-test and post-test of 10 sets of five trials of a throwing task with the non-preferred hand. In the practice phase, participants mentally practiced the throwing task and then mentally practiced a task that was similar, dissimilar, or completed an unrelated reading task. Performance for all groups improved from pre- to post-test; however, there were no differences in increases for the three groups. The findings suggest that mental practice of similar and dissimilar tasks produced no significant interference in performance.     

Influence of practice schedule on testing schema theory predictions in adults

Since the publication of Schmidt's (1975) schema theory of motor learning, numerous studies have assessed the variability of practice hypothesis. Of these, only research using children as subjects has provided consistent results. Findings from adult studies have been equivocal. Two experiments were conducted to assess the possibility that the schedule of variable practice during acquisition may be a clue to this equivocality, since only experiments (using adults as subjects) that have provide random variability of practice conditions have consistently supported the tenets of schema theory. Using a two movement rapid timing task, subjects learned to control their actions under one (constant) or four (variable) parameters, with variable practice conducted under either a blocked or a randomized schedule. Results for variable error and absolute constant error showed that random-variable practice provided strong support for the schema theory prediction, whereas blocked-variable practice provided only relatively weak support. Two contrasting implications of these results are discussed with respect to support versus non-support for Schmidt' schema theory.     

Influence of Practice Schedule on Testing Schema Theory Predictions in Adults

Since the publication of Schmidt’s (1975) schema theory of motor learning, numerous studies have assessed the variability of practice hypothesis. Of these, only research using children as subjects has provided consistent results. Findings from adult studies have been equivocal. Two experiments were conducted to assess the possibility that the schedule of variable practice during acquisition may be a clue to this equivocality, since only experiments (using adults as subjects) that have provided random variability of practice conditions have consistently supported the tenets of schema theory. Using a two movement rapid timing task, subjects learned to control their actions under one (constant) or four (variable) parameters, with variable practice conducted under either a blocked or a randomized schedule. Results for variable error and absolute constant error showed that random-variable practice provided strong support for the schema theory prediction, whereas blocked-variable practice provided only relatively weak support. Two contrasting implications of these results are discussed with respect to support versus non-support for Schmidt’s schema theory.     

Practice variability promotes an external focus of attention and enhances motor skill learning

Variability in practice has been shown to enhance motor skill learning. Benefits of practice variability have been attributed to motor schema formation (variable versus constant practice), or more effortful information processing (random versus blocked practice). We hypothesized that, among other mechanisms, greater practice variability might promote an external focus of attention on the intended movement effect, while less variability would be more conducive to a less effective internal focus on body movements. In Experiment 1, the learning of a throwing task was enhanced by variable versus constant practice, and variable group participants reported focusing more on the distance to the target (external focus), while constant group participants focused more on their posture (internal focus). In Experiment 2, golf putting was learned more effectively with a random compared with a blocked practice schedule. Furthermore, random group learners reported using a more effective distal external focus (i.e., distance to the target) to a greater extent, whereas blocked group participants used a less effective proximal focus (i.e., putter) more often. While attentional focus was assessed through questionnaires in the first two experiments, learners in Experiment 3 were asked to report their current attentional focus at any time during practice. Again, the learning of a throwing task was more effective after random relative to blocked practice. Also, random practice learners reported using more external focus cues, while in blocked practice participants used more internal focus cues. The findings suggest that the attentional foci induced by different practice schedules might be at least partially responsible for the learning differences.     

Effects of contextual interference and age on acquisition, retention, and transfer of motor skill.

This experiment was designed to investigate the varying conditions of contextual interference within three age groups. 40 5-yr.-olds, 40 7-yr.-olds, and 40 11-yr.-olds practiced the task of throwing beanbags under either low contextual interference (blocked practice), high contextual interference (random practice), or medium contextual interference (combined practice). All subjects performed 30 acquisition trials, 12 retention trials and 6 transfer trials. Analysis indicated that only the 7-yr.-old subjects differed in their performance in the various practice groups. As hypothesized and suggested by developmental theories, the combined and blocked practice groups acquired the task better. On the other hand, the 5- and 11-yr.-olds did not differ in performance in the different practice groups. Whether this is associated with difficulty of the task or the length of practice can be assessed in further study. Contextual interference in different age groups needs further investigation.     

Evidence for recognition and recall schemata

Two experiments manipulated elements postulated to be crucial for the formation of recognition and recall schemata for discrete motor skills. Experiment 1 tested predictions for the formation of a schema to recognize novel and practiced positioning movements. Sensations of practiced locations, followed by knowledge of results, enabled accurate judgment of movement extent. The specification of distances before active practice movements did not help recognition performance. To test recall schema, Experiment 2 allowed practice with active movements over specified distances, or unspecified passive movements. The allowance of response specifications during practice provided clear superiority of recall-dependent performance. This aspect of recall memory should enable the construction of movements with extents and velocities different from those practiced.     

Contextual Interference in Motor Learning: Dissociated Effects Due to the Nature of Task Variations

The contextual interference effect in motor learning refers to the interference that results from practising a task within the concept of other tasks in a practice session. Several studies have shown that practice under conditions of high contextual interference (i.e. with a random practice order) degrades performance during acquisition trials, compared to low contextual interference conditions (i.e. with a blocked order, where practice is completed on one task before practice on another task is undertaken). In contrast to acquisition performance, random practice usually leads to more effective learning than blocked practice, as measured by retention and transfer tests. One of the hypotheses regarding the effect suggests that a random practice schedule induces more extensive planning operations during practice than a blocked practice condition. If so, then differences between these two conditions should emerge to the degree that the set of tasks requires complete reconstruction of these planning operations on each trial. To address this issue, we compared four groups of subjects: a blocked and random group that practised three timing tasks that shared a common characteristic (same relative timing), and a blocked and random group that practised three tasks that each had different relative timing structures. Subjects practised these tasks on each of two days, with a retention test and two transfer tests that required either a relative timing structure that had been practised previously or had not previously been practised. No random/ blocked differences occurred regardless of the relative timing of the patterns during acquisition or retention. However, for both transfer tests, random practice enhanced learning only for the group that had practised with tasks that each had different relative timing during acquisition. Implications of these results for an explanation of contextual interference are discussed.     

Forgetting motor programmes: Retrieval dynamics in procedural memory

When motor sequences are stored in memory in a categorised manner, selective retrieval of some sequences can induce forgetting of the non-retrieved sequences. We show that such retrieval-induced forgetting (RIF) occurs not only in cued recall but also in a test assessing memory indirectly by providing novel test cues without involving recall of items. Participants learned several sequential finger movements (SFMs), each consisting of the movement of two fingers of either the left or the right hand. Subsequently, they performed retrieval practice on half of the sequences of one hand. A final task then required participants to enter letter dyads. A subset of these dyads corresponded to the previously learned sequences. RIF was present in the response times during the entering of the dyads. The finding of RIF in the slowed-down execution of motor programmes overlapping with initially trained motor sequences suggests that inhibition resolved interference between procedural representations of the acquired motor sequences of one hand during retrieval practice.     

A Sensorimotor Basis for Motor Learning: Evidence Indicating Specificity of Practice

Our previous work (Proteau, Marteniuk, Girouard, & Dugas, 1987) was concerned with determining whether with relatively extensive practice on a movement aiming task, as the skill theoretically starts becoming open-loop, there would be evidence for a decreasing emphasis on visual feedback for motor control. We eliminated vision of the moving limb after moderate and extensive practice and found that the movement became more dependent on this feedback with greater amounts of practice. In the present study, we wished to test the hypothesis, developed from our previous work, that at the base of movement learning is a sensorimotor representation that consists of integrated information from central processes and sensory feedback derived from previous experiences on the movement task. A strong test of this hypothesis would be the prediction that for an aiming task, the addition of vision, after moderate and relatively extensive practice without vision, would lead to an increasingly large movement decrement, relative to appropriate controls. We found good support for this prediction. From these and previous results, and the idea of the sensorimotor representation underlying learning, we develop the idea that learning is specific to the conditions that prevail during skill acquisition. This has implications for the ideas of generalized motor program and schema theory.