Performance of Faller and Nonfaller Older Adults on a Motor–Motor Interference Task

Typically, falls in older adults occur when 2 tasks are performed simultaneously, due to the increased motor demand required to maintain stability and attention to perform the other task. The authors' purpose was to investigate walking while grasping, transporting, and placing a dowel on a predetermined target while manipulating difficulty levels of the manual task. Faller and nonfaller older adults performed a walking block (manual tasks combined with gait) and a stationary block (upright stance combined with manual tasks). The manual task involved grasping, transporting, and placing the dowel over a target. The results showed that fallers underperformed when compared with nonfallers in the task of placing the dowel over the target. The main difference observed between the groups was found in the condition that required allocation of attention between tasks and greater accuracy in the final placement of the object. Fallers showed gait stability similar to the nonfallers, but fallers were less accurate than nonfallers in the object placement task, especially for the highest level of difficulty. Thus, fallers seem to use a stability-first strategy. Fallers had problems in executing the manual tasks, which suggests a more global change in motor behavior rather than specific changes to balance control.     

Are Conflicts the Motor in Identity Change?

This paper aims to find empirical evidence for the assumption that conflicts are the motor of identity development. I hypothesized that conflicts in a specific domain cause an increase in exploration, a decrease in the strength of commitments, and a change in the content of commitments in that same domain. Eight participants kept a diary in which they reported the most important events during 6 months. The identity status in 6 domains before and after the diary period was assessed. Strong commitments with little exploration were preceded by a period of little or no conflicts in the relevant domain. Perceived change in content of commitments and decrease in strength of commitments were related to the number of conflicts during that same period, but exploration was not. This might be explained by the finding that most conflicts lasted much longer than 6 months. Using resampling techniques, significant results were found when we analyzed the 48 domains, but we cannot rule out the possibility that systematic differences between participants affected the findings.     

A Developmental Explanation For Children’s Motor behavior

Two experiments were conducted to test the application of Pascual-Leone’s (1970) neo-Piagetian theory for explaining children’s acquisition of skill in a curvilinear positioning task. Two groups of children (late pre-operational 6 yr olds and early concrete 8 yr olds) were identified and from each group 10 low M-processors and 10 high M-processors were selected (total n=40) through use of the Children’s Embedded Figures Test. The 6 yr olds were administered 2-and 3-scheme curvilinear positioning tasks while the 8 yr olds performed 3-and 4-scheme tasks. The difference between the two experiments was the nature of the positioning tasks, i.e., one task allowed visual processing of information, while the other did not. Both experiments supported the neo-Piagetian predictions of structural mental space as explaining the developmental nature of motor skill acquisition, and functional mental space as explaining individual differences within stages in children’s performance.     

A Re-Evaluation of the Motor Inhibition — Fantasy Hypothesis

Because support for the hypothesis that motor inhibition stimulates fantasy is based entirely on changes in the Rorschach M response, the generality of the phenomenon is in doubt and was tested by observing the effect of restricted motility on TAT productions, scored for fantasy with the Transcendence Index. The influences of general activity level and daydreaming tendency also were studied, as well as the hypothesis that motor inhibition specifically affects only fantasy about movement. No change in movement fantasy, non-movement fantasy, or total fantasy was found in the present study, suggesting that previous investigators may have overstated the case in inferring that total fantasy is stimulated by motor inhibition. Rather, some property specific to the M response may be involved, and some speculation about its nature is offered.     

Motor imagery and ‘placebo-racket effects’ in tennis serve performance

ObjectivesThis study aimed at confirming whether Motor Imagery (MI) enhances tennis serve performance, and determining whether a placebo condition could affect the beneficial effects of MI.DesignThis study used a 3 × 2 factorial design. Three groups of tennis players were compared in service performance outcomes before and after a training session.MethodsTwenty-two tennis players were assigned into three groups: a control (C) and two experimental groups subjected to a similar MI intervention, one group using their regular own racket (MI group) while the other used a placebo racket (P group).ResultsAnalyses of Covariance revealed no significant group difference when comparing serve velocity after training session, but MI training improved serve accuracy and regularity. Combining placebo racket with MI further resulted in greater serve accuracy score as compared to MI alone. Players' perception of their serve quality improved after MI, and this effect was reinforced in the P group.ConclusionThese findings revealed that MI may be useful to achieve peak performance, and that the implement placebo effect might be a factor in sport performance, hence promoting the beneficial effects of alternative methods to improve tennis serve performance.     

Comment on “Retention Characteristics of Motor Short-Term Memory Cues”

Marteniuk (1973) used negative results, which may be attributed to a lack of power, to question the adequacy of variable error as a measure of forgetting. He also used these negative results, along with constant error results which were consistent with the Laabs (1971, 1973) model of motor memory, to reject parts of the model related to variable error. Caution is advised when interpreting negative results and interchanging dependent measures.     

Are Motor Inhibition and Cognitive Flexibility Dead Ends in ADHD?

Executive dysfunction has been postulated as the core deficit in ADHD, although many deficits in lower order cognitive processes have also been identified. By obtaining an appropriate baseline of lower order cognitive functioning light may be shed on as to whether executive deficits result from problems in lower order and/or higher order cognitive processes. We examined motor inhibition and cognitive flexibility in relation to a baseline measure in 816 children from ADHD and control families. Multiple children in a family were tested in order to examine the familiality of the measures. No evidence was found for deficits in motor inhibition or cognitive flexibility in children with ADHD or their nonaffected siblings: Compared to their baseline speed and accuracy of responding, children with ADHD and their (non)affected siblings were not disproportionally slower or inaccurate when demands for motor inhibition or cognitive flexibility were added to the task. However, children with ADHD and their (non)affected siblings were overall less accurate than controls, which could not be attributed to differences in response speed. This suggests that inaccuracy of responding is characteristic of children having (a familial risk for) ADHD. Motor inhibition and cognitive flexibility as operationalized with mean reaction time were found to be familial. It is concluded that poorer performance on executive tasks in children with ADHD and their (non)affected siblings may result from deficiencies in lower order cognitive processes and not (only) from higher order cognitive processes/executive functions.     

Preschoolers’ Motor and Verbal Self-Control Strategies During a Resistance-to-Temptation Task

Although prior research has shown that young children exhibit enhanced self-control when they use verbal strategies provided through adult instructions, little work has examined the role of children's spontaneous verbalizations or motor behavior as strategies for enhancing self-control. The present study examined the usefulness of spontaneous verbal and motor strategies for 39 3- and 4-year-old children's ability to exercise self-control during a resistance-to-temptation task. After a 2-min play period, participants were asked by an experimenter not to touch an attractive train set while he was out of the room. Children were videotaped during the 3-min waiting period and videos were coded for frequency and duration of touches, motor movements, and verbalizations. Results indicated that self-control was improved by using both motor and verbal strategies. Children who were unable to resist touching the forbidden toy used limited motor or verbal strategies. These findings add to the growing literature demonstrating the positive role of verbalizations on cognitive control and draw attention to motor behaviors as additional strategies used by young children to exercise self-control.     

Does Narrative Feedback Enhance Children's Motor Learning in a Virtual Environment?

Augmented feedback has motivational and informational functions in motor learning, and is a key feature of practice in a virtual environment (VE). This study evaluated the impact of narrative (story-based) feedback as compared to standard feedback during practice of a novel task in a VE on typically developing children's motor learning, motivation and engagement. Thirty-eight children practiced navigating through a virtual path, receiving narrative or non-narrative feedback following each trial. All participants improved their performance on retention but not transfer, with no significant differences between groups. Self-reported engagement was associated with acquisition, retention and transfer for both groups. A narrative approach to feedback delivery did not offer an additive benefit; additional affective advantages of augmented feedback for motor learning in VEs should be explored.     

Is Mental Rotation Ability a Predictor of Success for Motor Performance?

Previous studies provided evidence of a relationship between mental rotation (MR) and motor processes in children and adults. However, there is no direct evidence that MR ability is a reliable predictor of success for motor performance. After completion of a MR test, the motor performance of 7- to 8-year-old and 11- to 12-year-old children was measured along a steeple chase and an equivalent straight distance sprint. The chase involved several motor actions requiring, among different competencies, spatial abilities such as performing a forward roll, jumping, crawling, turning, and changing directions. Data revealed that the time taken to complete the chase was influenced by speed and sex, but also by the individual MR ability. Based on these findings, we assume that MR and motor performance may share similar subprocesses.     

Motor Imitation in Young Children with Autism: What's the Object?

Two studies investigated the nature of motor imitation in young children with autism. Study 1 compared different types of motor imitation in 18 autistic children, 18 children with developmental delay, and 18 normally developing children. Results revealed weaker imitation skills for the autistic group, though all groups demonstrated a similar pattern of performance across different imitation domains. Imitation of body movements was more difficult than imitation of actions with objects, and imitation of nonmeaningful actions was more difficult than imitation of meaningful actions. Study 2 investigated concurrent and predictive relations between imitation and other developmental skills within a sample of 26 two-year-old children with autism. Results suggested that imitation of body movements and imitation of actions with objects represent independent dimensions. Imitation of body movements was concurrently and predictively associated with expressive language skills, and imitation of actions with objects was concurrently associated with play skills. Improvements in both motor imitation domains occurred over a 1-year period.     

How do Motor Systems Deal with the Problems of Controlling Three-Dimensional Rotations?

Rotations are fundamental to motor control, not only for orienting to stimuli but also in the joint articulations that underlie translational movements. Studying three-dimensional (3-D) rotations of the simplest joint system, the eye, has provided general insights into the neural control of movement. First, in selecting one 3-D eye orientation for each two-dimensional (2-D) gaze direction, the oculomotor system generates a behavior called Listing's law that constrains eye position to a 2-D plane, Listing's plane. This selection is made internally by an inverse kinematic transformation called the Listing's law operator. Second, the oculomotor system incorporates the inherent multiplicative relationship between rotational velocity and position to generate the 3-D movement and position commands required by Listing's law. Finally, the coordinate systems for these commands appear to align with Listing's plane rather than with anatomic structures. Recent investigations have revealed similar behavioral constraints in the orientations of the head and arm, suggesting that the neural mechanisms for Listing's law may have analogues in many motor systems.     

Relations between Preschool Children’s Fine Motor Skills and General Cognitive Abilities

ABSTRACT

An increasing number of findings suggest that cognition is grounded in sensorimotor experiences. Research suggests that fine motor skills (FMS) link to cognitive abilities. Existing studies, however, lack conceptual and methodological differentiation regarding FMS and little is known about the directional nature of links. In study 1, we measured three types of FMS, namely dexterity, grapho-motor skill, speed-dominated FMS in a sample of preschool children (n = 78) aged 4.42 years, and analyzed their links with nonverbal reasoning and general knowledge. Factor analyses verified the existence of these three distinct subsets of FMS. A unique link was found for dexterity and reasoning after controlling for age, attention and processing speed. In study 2, using a cross-lagged-panel design with two measurement points one year apart in preschool (n = 84), a cross-lagged link from four-year-old children’s dexterity to their reasoning skills at age five was demonstrated. Findings support the idea of FMS being involved in the development of cognitive abilities.     

Stimulation through simulation? Motor imagery and functional reorganization in hemiplegic stroke patients

A key factor influencing reorganization of function in damaged neural networks of the adult brain is stimulation. How to stimulate motor areas of patients with paralyses is a formidable challenge. One possibility is to use internal movement simulations, or motor imagery, as an alternative to conventional therapeutic interventions that require voluntary limb movements. Before this alternative can be entertained, two preliminary issues must be resolved. First, do internal movement simulations involve the same neural circuits as comparable overt actions? Second, are motor-impaired populations capable of imagining movements they can no longer perform? Here, I show that under specific conditions, answers to these questions are affirmative. Further, I discuss preliminary evidence that internally simulating movements may induce functional reorganization of the contralesional hand representation of a chronic, densely hemiplegic, cerebral vascular accident (CVA) patient.     

Understanding or feeling? Motor and sensory processes in recall of haptic experiences

Effects of learning can show in a direct, i.e., explicit way, or they can be expressed indirectly, i.e., in an implicit way. It is investigated whether hepatic information shows implicit effect, and whether implicit haptic memory effects are based primarily on motor or on sensory memory components. In the first phase blindfolded subjects had to palpate objects in order to answer questions about the objects' distinct properties as fast as possible. In the following phase this task was repeated with the same objects and additional control items. Additionally, recognition judgements were required. Results demonstrate reliable effects of implicit memory for haptic information in terms of reaction times to old vs. new objects. Subjects who had to wear plastic gloves in the first stage showed comparable effects of repetition priming. Changing the questions--and, thus, hand movements--during the palpitation of objects known from the first stage, however, abolishes implicit memory expression. It is concluded, therefore, that implicit memory for haptic information is based on motor processes. On the other hand, explicit memory is hampered in subjects wearing gloves during the first phase, as revealed in terms of recognition performance while changing the questions about objects' properties has no effect on recognition judgements. Thus, explicit memory for haptic information seems to be based on the sensory processes when touching objects.