Effect of motor cognition program for improving temporal-spatial timing memory ability with mild cognitive impairment patients

This exploratory study evaluated motor cognition program for improving temporal-spatial timing memory ability with mild cognitive impairment (MCI) patients. The purpose was to explore the efficacies of motor cognition program according to practice methods, centering on coordination and observation pattern. Two practice methods were applied to the 40 MCI elder. In experiment 1, participants divided into two group as, one-hand practice group (n=20) and both-hands practice group (n=20). In experiment 2, participants divided into two group as, active observation group (n=20) and passive observation group (n=20). The participant was asked to alternatively press two buttons 6 times with the index finger hand with goal rhythm pattern (3,600 msec in total duration). In coordination pattern, bimanual practice was more effective for improving temporal-spatial timing memory ability than unilateral practice. In observation pattern, active observation showed better learning effect than passive observation. However, there was a learning effect even in passive observation pattern. Such a result claimed for the elderly, who has problem to do daily activity, could use observation of temporal-spatial timing task for improving cognitive ability.

Production and perception of legato, portato, and staccato articulation in saxophone playing

This paper investigates the production and perception of different articulation techniques on the saxophone. In a production experiment, two melodies were recorded that required different effectors to play the tones (tongue-only actions, finger-only actions, combined tongue and finger actions) at three different tempi. A sensor saxophone reed was developed to monitor tongue-reed interactions during performance. In the slow tempo condition, combined tongue-finger actions showed improved timing, compared to the timing of the tongue alone. This observation supports the multiple timer hypothesis where the tongue's timekeeper benefits from a coupling to the timekeeper of the fingers. In the fast tempo condition, finger-only actions were less precise than tongue-only actions and timing precision of combined tongue-finger actions showed the higher timing variability, close to the level of finger-only actions. This suggests that the finger actions have a dominant influence on the overall timing of saxophone performance. In a listening experiment we investigated whether motor expertise in music performance influences the perception of articulation techniques in saxophone performance. Participants with different backgrounds in music making (saxophonists, musicians not playing the saxophone, and non-musicians) attended an AB-X listening test. They had to discriminate between saxophone phrases played with different articulation techniques (legato, portato, staccato). Participants across all three groups discriminated the sound of staccato articulation well from the sound of portato articulation and legato articulation. Errors occurred across all groups of listeners when legato articulation (no tonguing) and portato articulation (soft tonguing) had to be discriminated. Saxophonists' results were superior compared to the results of the other two groups, suggesting that expertise in saxophone playing facilitated the discrimination task.

Influence of task on interlimb coordination in adults with cerebral palsy

OBJECTIVE

To examine movement time and kinematic properties of unilateral and bilateral reaching movements in adults with cerebral palsy (CP), focusing on how different types of bilateral movements, simultaneous or sequential, may influence interlimb coordination.

DESIGN

Quantitative study using between-group repeated-measures analyses.

SETTING

Motor control laboratory at a research university.

PARTICIPANTS

Adults with hemiplegic CP (n=11; mean age ± SD, 33±10y; 4 men) and age-matched controls (mean age ± SD, 32±9y; 4 men).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Movement time (MT), maximum deviation from a straight trajectory to the target, and peak speed.

RESULTS

Although adults with hemiplegic CP showed strong unilateral deficits, bilateral simultaneous reaching movements were temporally and spatially coupled. Movement of the less affected arm slowed to match the movement of the more affected arm. In contrast, bilateral sequential movements improved MTs of the less affected and more affected arms.

CONCLUSIONS

Bilateral sequential movements were conducive to faster MT compared with unilateral or bilateral simultaneous movements. Training that includes bilateral sequential movements may be beneficial to adults with hemiplegic CP. Upper-limb movements are coordinated in a variety of ways to perform routine bilateral tasks. Some bilateral tasks, such as stacking boxes, require more symmetric movements of the upper limbs. Other bilateral tasks, such as opening the refrigerator with 1 hand while placing an item on the shelf with the other hand, emphasize coordinated sequential action between upper limbs. Despite the prevalence of integrative upper-limb use, the control of different forms of bilateral movement is not well understood. A more comprehensive knowledge of upper-limb bilateral movements may hold important implications for developing more effective upper-limb movement therapies.

Theories and models for 1/f(beta) noise in human movement science

Human motor behavior is often characterized by long-range, slowly decaying serial correlations or 1/f(beta) noise. Despite its prevalence, the role of the 1/f(beta) phenomenon in human movement research has been rather modest and unclear. The goal of this paper is to outline a research agenda in which the study of 1/f(beta) noise can contribute to scientific progress. In the first section of this article we discuss two popular perspectives on 1/f(beta) noise: the nomothetic perspective that seeks general explanations, and the mechanistic perspective that seeks domain-specific models. We believe that if 1/f(beta) noise is to have an impact on the field of movement science, researchers should develop and test domain-specific mechanistic models of human motor behavior. In the second section we illustrate our claim by showing how a mechanistic model of 1/f(beta) noise can be successfully integrated with currently established models for rhythmic self-paced, synchronized, and bimanual tapping. This model synthesis results in a unified account of the observed long-range serial correlations across a range of different tasks.

Interval timing and trajectory in unequal amplitude movements

The Wing-Kristofferson (WK) model of movement timing emphasises the separation of central timer and motor processes. Several studies of repetitive timing have shown that increase in variability at longer intervals is attributable to timer processes; however, relatively little is known about the way motor aspects of timing are affected by task movement constraints. In the present study, we examined timing variability in finger tapping with differences in interval to assess central timer effects, and with differences in movement amplitude to assess motor implementation effects. Then, we investigated whether effects of motor timing observed at the point of response (flexion offset/tap) are also evident in extension, which would suggest that both phases are subject to timing control. Eleven participants performed bimanual simultaneous tapping, at two target intervals (400, 600 ms) with the index finger of each hand performing movements of equal (3 or 6 cm) or unequal amplitude (left hand 3, right hand 6 cm and vice versa). As expected, timer variability increased with the mean interval but showed only small, non-systematic effects with changes in movement amplitude. Motor implementation variability was greater in unequal amplitude conditions. The same pattern of motor variability was observed both at flexion and extension phases of movement. These results suggest that intervals are generated by a central timer, triggering a series of events at the motor output level including flexion and the following extension, which are explicitly represented in the timing system.

The effects of age and attention on motor overflow production—A review

Motor overflow refers to overt involuntary movement, or covert muscle activity, that sometimes co-occurs with voluntary movement. Various clinical populations exhibit overflow. Motor overflow is also present in healthy children and the elderly, although in young adults, overt overflow is considered abnormal unless elicited under conditions of extreme force or muscle fatigue. Current theories of overflow imply that the corpus callosum may mediate production of this phenomenon. However, given that the corpus callosum is a conduit enabling the transfer of cortical information, surprisingly few studies have considered the cortical or subcortical structures underlying overflow. This review considers the developmental trend of motor overflow production, specifically in the upper-limbs, and the mechanisms thought to underlie this age-related phenomenon. Potential neurological correlates of motor overflow will be discussed in conjunction with higher order attentional processes which also regulate motor overflow production. Future research investigating the impact of attentional processes on overflow production may be particularly valuable for designing rehabilitation strategies for patients experiencing induced pathological overflow or conversely, to develop techniques to encourage the recovery of movement function in individuals with paretic limbs.

Explanatory limitations of the HKB model: Incentives for a two-tiered model of rhythmic interlimb coordination

The HKB model for rhythmic interlimb coordination has highlighted the importance of coordinative stability and loss of stability, and introduced, with this focus, a new set of explanatory constructs. However, the phenomenological character of both parts of this model (i.e., the potential and the associated system of coupled oscillators) precludes an understanding of how the observed stability characteristics are related to more specific (e.g., biomechanical and neurophysiological) aspects of the movement system. A two-tiered model (involving a distinction between 'neural' and 'effector' dynamics) is discussed that offers handles for addressing such underpinnings of the identified coordination dynamics. The promise of the model in this regard is illustrated by two recent studies showing how explicit accounts of the effector dynamics may help disclose why (and how) particular properties of the peripheral system affect the overall coordination dynamics.