The performance of a simple motor task with kinaesthetic sense loss

Two related studies were carried out, to test the suitability of the nerve compression block as a technique in the investigation of kinaesthesis in motor skills.

In both studies a key tapping task was used. Each experimental group was composed of six volunteer subjects. It was found that kinaesthetic sensation was eliminated after pressure had been applied for 20-25 min., but muscle power was not seriously affected at this stage of the block. The results also showed a pronounced performance decrement in the absence of kinaesthetic feedback, and that this decrement was not due to emotional or other disturbances caused by the experimental procedure. The loss of tactile sensation was also observed.     

Training of fast tapping with reduction of kinaesthetic, tactile, visual and auditory sensations

Five subjects were trained to tap on a light Morse-key during nerve compression block. The training sessions lasted for 40 sec., with a 5 sec. rest after the first 20 sec. work period. The group learning curve reached 89.5 per cent. level of normal performance by the eighth training session. In the ninth, the testing session, subjects tapped with visual and auditory sense reduction superimposed on the kinaesthetic and tactile impariment of the training condition. Performance in the testing session reached 40.9 per cent. of normal.

The sixth subject was trained in the same task as the other five subjects, but the training condition included elimination of cues from all four sensory channels. He reached 79.09 per cent. of his normal tapping performance in the seventh session.

These results show that the motor skill of tapping can be relearned in the absence of kinaesthetic cues. Furthermore when the subject has no conscious knowledge of any peripheral sensory cues connected with the ongoing motor activity, learning can nevertheless take place. These findings lead to the hypothesis, that skilled motor activity can be monitored by central processes alone.

During the training sessions subjects showed a tendency of tapping in groups of gradually increasing length. It is hypothesized that increased number of taps forming a group gives an indication to the possible mode of action of these central processes.     

Perceptual-motor development and prevention of clumsiness

Summary This longitudinal study, following children's development over three years, examines the developmental trends in the processes underlying perceptual-motor behaviour. Entry into the study was at first year of primary school, at age 6. The study has three aims: (1) to obtain developmental trends in kinaesthesis and motor-programming processes; (2) to examine the relationship between slow kinaesthetic and motor development; (3) to establish the effect of accelerated kinaesthetic development and prevention of perceptual-motor dysfunction (clumsiness). The results to date show that over 60% of children entering primary school have not developed the kinaesthetic ability necessary for the acquisition and learning of educationally demanded motor skills. Kinaesthetic development is accelerated spontaneously in some children as a response to educational demands; in others a single exposure to kinaesthetic input triggers significant improvement. In the remaining 17% kinaesthetic training can alleviate the kinaesthetic dysfunction. At age 5–6 years only 25 children (8.1%) performed the Perceptual-Motor Abilities Test at levels indicative of perceptual-motor dysfunction. Of these, 13 children (4.2%) were identified as having motor difficulties. These low incidence rates indicate that a low level of kinaesthetic ability has no effect on general motor function at the beginning of schooling, and that only when competence in complex motor skills is expected, from the third year of schooling, does perceptual-motor dysfunction (PMD) become manifest.The work reported in this article was supported by Australian Research Council Grant number A78931998     

Motor proficiency and emotional/behavioural disturbance in autism and Asperger's disorder: another piece of the neurological puzzle?

The relationship of motor proficiency with emotional/behavioural disturbance, autistic symptoms and communication disturbance was investigated in children diagnosed with autism and Asperger's disorder (AD). The Movement Assessment Battery for Children was used as a measure of motor impairment, and the Developmental Behavioural Checklist was used as a measure of emotional/behavioural disturbance in the following groups: AD (n?=?22), high functioning autism (HFA) (n?=?23), LFA (n?=?8) and typically developing children (n?=?20). The HFA group had more difficulty with motor items, such as ball skills and balance, than did the AD group. There were significant positive correlations between impairments in motor proficiency (in particular ball skills and balance) and emotional/behavioural disturbance, autistic symptoms and communication disturbance. These findings are consistent with the hypothesis that there are qualitative and quantitative differences in the motor profile between autism and AD. In addition, the association between motor proficiency impairment and emotional/behavioural disturbance in autism and AD emphasizes the importance for screening of co-occurring emotional/behavioural symptoms in individuals with motor difficulties. These findings have implications for the potential use of adjunct motor measures in the diagnosis and definition of autism spectrum disorders.     

Human behaviour and development under high-altitude conditions

Although we are far from a universally accepted pattern of impaired function at altitude, there is evidence indicating motor, perceptual, memory and behavioural deficits in adults. Even relatively low altitudes (2500 m) may delay reaction time, and impair motor function. Extreme altitude exposure (>5000 m) may result in more pronounced impairment that can persist after returning to the lowlands. Research into the effects of altitude exposure earlier in development is lacking by comparison. Un-acclimatized children can suffer from acute mountain sickness, and, in native populations born at altitude, subtle cognitive and behavioural deficits suggest incomplete adaptation to hypoxia. The study of neurobehavioural functioning at altitude may provide important information about the effects of clinical hypoxia on the human brain and behavioural development.     

Processing a display even after you make a response to it. How perceptual errors can be corrected

We know that when people make responses which they did not intend they can discover this by monitoring kinaesthetic and visual feedback. It is less clear whether they can also correct perceptual errors which occur when they mistake one signal for another. It was argued that, if they can sometimes do this, extra errors which occur when discriminations become more difficult may be detected and corrected. Experiment I compared the ability of young fit subjects to detect errors made during easy and during difficult discriminations between tone signals. There was no evidence that any additional errors made to difficult discriminations were detected. Fast errors were detected, slower errors were not. The results were consistent with the idea that subjects can detect fast motor errors by monitoring feedback, but that they cannot detect perceptual mistakes.

In Experiment II subjects made easy and difficult line length discriminations. Displays lasted for 100 ms, 200 ms or 500 ms and were followed by random masks. In this case, fast errors were again corrected more frequently than slow errors but eight aspects of the data suggest that subjects could, and did, correct perceptual as well as motor mistakes and that they managed to do this by continuing to process a display after the moment at which they may have initiated an impulsive response to it. The data are interpreted in terms of a “Committee Decision” model for extended perceptual processing previously applied to other, similar data by Rabbitt and Rodgers (1977) and Rabbitt, Cumming and Vyas (1978).     

Response-stimulus interval in choice serial reaction time: Interaction with sleep deprivation, choice, and practice

In choice serial reaction time (RT), Response-to-next-Stimulus Interval (RSI) was varied from 0 to 600 msec in 40-msec steps. In three experiments, RT fell and errors rose as RSI was increased to 480 msec; they remained unchanged thereafter. The effect of RSI on RT was not linear, was reduced by 6- as compared with 4- or 3-choice responding, and was unaffected by sleep deprivation, despite loss of sleep reducing RT overall. The effect of penultimate RSI on RT was similar to that current RSI, but smaller. Two explanations of RSI—response-generated kinaesthetic feedback blocking a “central processor” and a preparatory interval as in warned simple RT—are rejected. Instead, the idea of “relative refractory state” is revived but now, because of the RSI/error finding, biased more towards responding than stimulus reception and encoding. In all three experiments the influence of RSI on RT was reduced with practice. If practice encourages automatic rather than controlled processing (Shiffrin & Schneider, 1977), the prediction is that the former will show less refractoriness.     

Kinaesthesis: Its measurement, training and relationship to motor control

This paper reviews studies which demonstrate the importance of kinaesthesis in the acquisition and performance of motor skills. A method of measuring kinaesthetic sensitivity in children and adults (recently developed) is briefly described. Developmental trends in kinaesthetic perception are discussed and large individual differences found within age groups. It was shown that kinaesthetically undeveloped children can be trained to perceive and memorize kinaesthetic information with greatly improved accuracy. Furthermore perceptual training facilitates the performance of a drawing skill. On the basis of these results an argument is made for the importance of kinaesthesis in skilled motor behaviour.     

Acoustic factors in visual search

Previous work has shown that in searching for existing or absent “e.s” in printed prose, the presence or absence of silent “e.s” was less likely to be detected than that of pronounced “e.s.” It was suggested that the acoustic or kinaesthetic “image” was searched for evidence of an “e” in addition to the visual stimulus and that evidence from both sources was considered in making the appropriate response.

The present experiment employs mainly substitutive errors within words, which may or may not change their pronunciation. The results suggest that the form of the acoustic correlates has no bearing upon whether the words are detected as wrongly spelt, but that the presence or absence of an acoustic event corresponding in time to the spatial location of the error is important.     

Feedback control of hand-movement and Fitts' law

Fitt's empirical result is stated and its information theoretic interpretation briefly discussed. An alternate derivation from a model assuming continous velocity control of hand position is shown to fit the motion time data equally well. Detailed studies of hand motion trajectories in Fitts' reciprocal tapping task have confirmed the exponential target approach predicted by this model but also revealed systematic fluctuations that it cannot explain. A further alternate model is therefore presented, based on intermittent feedback with target approach by a sequence of discrete positional corrective motion “impulses”. The second model also predicts motion times in accord with Fitts' Law.

Detailed studies of target aimed translational hand and rotary wrist motions have shown that the intermittent corrective impulses are of approximately Gaussian integral form, with minimum s.d. on the order of 30 msec. for wrist rotation, and recurrence rate about 10/s. Mechanical and physiological interactions capable of explaining this corrective impulse trajectory are discussed, and a model based on balance of forces between agonist and antagonist muscles is briefly developed. The interaction between external (visual) and internal (proprioceptive or kinaesthetic) feedback channels determining impulse amplitude is discussed in the light of results obtained using force disturbance and with amplified, attenuated or delayed visual feedback. It seems that an internal “secondary positional reference” must be postulated to explain results obtained when S is deprived of visual feedback.     

A longitudinal study of motor ability and kinaesthetic acuity in young children at risk of developmental coordination disorder

Several studies have linked poor kinaesthetic ability with poor motor coordination in school-aged children. However, few studies have investigated kinaesthesis in younger children. The aim of this study was to determine if preschool aged children who have been identified as at risk of developing developmental coordination disorder (DCD) have poorer kinaesthetic ability than matched controls. Kinaesthetic ability and performance IQ were examined in a group of children aged between 4 and 5 years. Following individual assessment of 291 children, 31 were identified as at risk of DCD at this age. One year later, 30 of these children were retested, and 23 were still found to be at risk. These children were matched on verbal IQ, age and sex with control children and their performance compared on the kinaesthetic acuity test (KAT) [D.J. Livesey and N.A. Parkes, Aust. J. Psychol., 47 (1995) 160] and three subtests of the WPPSI-R performance IQ (D. Wechsler, Manual for the Wechsler preschool and primary scale of intelligence--revised, Psychological Corporation, New York, 1989). Both the KAT and the performance subtest scores were found to be significantly poorer in the children at risk of DCD. Follow-up testing one year later showed that both groups improved their kinaesthetic acuity score although the control children remained significantly better than the children with poor motor coordination.     

Phenobarbitone and kinaesthetic after-effect

The effect of phenobarbitone (phenobarbital), predominantly a central depressant, on kinaesthetic after-effect was examined. The subjects were selected after a preliminary testing with the Maudsley Personality Inventory. They were classified into two groups: extraverts and introverts. The drug was used at different dose levels. A 2 × 4 randomized block design was replicated ten times. The study supports the following conclusions: (a) the extraverted subjects show larger kinaesthetic after-effect than introverted subjects under placebo condition; (b) phenobarbitone has no effect on kinaesthetic after-effects in extraverted subjects except in small doses (30 mg) which reduce the size of the effect; (c) the drug in larger doses (60 mg and 100 rng) produces a significant increasing effect in the introverted group.     

Investigating the dose-response relationship between motor imagery and motor recovery of upper-limb impairment and function in chronic stroke: A scoping review

The recovery of upper-limb impairment and dysfunction post-stroke is often incomplete owing to the limited time in therapy focused on upper-limb recovery and the severity of the impairment. In these cases, motor imagery (MI) may be used as a precursor to physical therapies to initiate rehabilitation early on when it would be otherwise impossible to engage in therapy, as well as to increase the dose of therapy when MI is used in adjunct to physical therapy. While previous reviews have shown MI to be effective as a therapeutic option, disparity in findings exists, with some studies suggesting MI is not an effective treatment for post-stroke impairment and dysfunction. One factor contributing to these findings is inconsistency in the dose of MI applied. To explore the relationship between MI dose and recovery, a scoping review of MI literature as a treatment for adult survivors of stroke with chronic upper-limb motor deficit was performed. Embase, Medline and CINHAL databases were searched for articles related to MI and stroke. Following a two-phase review process, 21 papers were included, and data related to treatment dose and measures of impairment and function were extracted. Effect sizes were calculated to investigate the effect of dosage on motor recovery. Findings showed a high degree of variability in dosage regimens across studies, with no clear pattern for the effect of dose on outcome. The present review highlights the gaps in MI literature, including variables that contribute to the dose-response relationship, that future studies should consider when implementing MI.     

Reduced corticomotor excitability with cyclic passive movement: a study using transcranial magnetic stimulation

Human voluntary movement involves the integration of kinaesthetic information with efferent motor activity during the planning and execution stages of movement. While much is known of the inhibitory and excitatory effects resulting from activation of specific kinaesthetic sensory receptors, in the present study we employed cyclic passive movement of the index finger in order to activate a range of kinaesthetic receptors in a manner that was intended to correspond to how these receptors might be active during a comparable voluntary movement. We intended to identify how this passive movement protocol might affect the excitability of the corticomotor pathway. During 1 Hz cyclic passive movement of the index finger there was an approximately 60% reduction in the amplitude of the motor evoked response from the first dorsal interosseous muscle. The results of the present study demonstrate that passive movement can have a profound effect on the excitability of the corticomotor pathway.     

Behavioural inhibition and the age at social isolation in rats

Rats that were socially isolated or group-housed at weaning were re-housed at 51 days of age in either the same housing condition or the opposite housing condition until 91 days and throughout subsequent behavioural testing. Increased resistance to extinction of running in an alley and poorer Hebb-Williams maze learning were found only after social isolation between 23 and 51 days of age. In contrast, slower running to reach the water reward during alley training and lower rearing activity at the beginning of open field testing were evident only in rats that were isolated at the time of testing. As in previous studies, open field hyperactivity was found in rats isolated at weaning but slower emergence latency was found in animals isolated at the time of testing. These findings confirm that the many behavioural effects of social isolation at different ages do not reflect a unitary aetiology. The behaviour of rats isolated at weaning is suggestive of a “disinhibition syndrome” but the precise nature of this syndrome is as yet unclear.     

Urban cyclists’ perspectives on post-collision behaviour change: A qualitative study

This study explores whether urban cyclists change on-road cycling behaviour following a collision(s) with a motor vehicle, an area that has not been explored in quantitative and qualitative transportation research. Purposive sampling was employed and data was collected through semi-structured in-depth interviews with 9 males and 9 females from Toronto, Canada. An inductive realist thematic method was used to analyze the data. Overall, three main themes were drawn out: cycling reflexivity, cycling behavioural change and resistance to cycling behavioural change. Eliciting the theme of cycling reflexivity, these findings reveal that all post-collision cyclists actively contemplated behavioural change, and the adoption or resistance toward cycling behavioural change was influenced by intersectional internal and external dispositions emanating from pre-collision cycling behaviours. By adopting general modifications and or defensive cycling practices, in total, 12 cyclists described cycling behavioural change. In contrast, eliciting the resistance toward cycling behavioural change theme, 6 participants indicated that there were no observable modifications in post-collision cycling behaviour. Grounded in the locus of control theory and the health belief model, this study elucidates cycling behavioural change as a psychological and behavioural coping mechanism employed by this particular cohort of cyclists in an effort to mitigate future collisions with motor vehicles. These novel findings set the stage for future research into cyclists’ post-collision experiences grounded in psychological and or behavioural research paradigms.     

What can functional neuroimaging tell the experimental psychologist?

I argue here that functional neuroimaging data—which I restrict to the haemodynamic techniques of fMRI and PET—can inform psychological theorizing, provided one assumes a “systematic” function-structure mapping in the brain. In this case, imaging data simply comprise another dependent variable, along with behavioural data, that can be used to test competing theories. In particular, I distinguish two types of inference: function-to-structure deduction and structure-to-function induction. With the former inference, a qualitatively different pattern of activity over the brain under two experimental conditions implies at least one different function associated with changes in the independent variable. With the second type of inference, activity of the same brain region(s) under two conditions implies a common function, possibly not predicted a priori. I illustrate these inferences with imaging studies of recognition memory, short-term memory, and repetition priming. I then consider in greater detail what is meant by a “systematic” function-structure mapping and argue that, particularly for structure-to-function induction, this entails a one-to-one mapping between functional and structural units, although the structural unit may be a network of interacting regions and care must be taken over the appropriate level of functional/structural abstraction. Nonetheless, the assumption of a systematic function-structure mapping is a “working hypothesis” that, in common with other scientific fields, cannot be proved on independent grounds and is probably best evaluated by the success of the enterprise as a whole. I also consider statistical issues such as the definition of a qualitative difference and methodological issues such as the relationship between imaging and behavioural data. I finish by reviewing various objections to neuroimaging, including neophrenology, functionalism, and equipotentiality, and by observing some criticisms of current practice in the imaging literature.     

Practice Effects on Motor Control in Healthy Seniors and Patients with Mild Cognitive Impairment and Alzheimer's Disease

ABSTRACT

This research was designed to test the hypothesis that motor practice can enhance the capabilities of motor control in healthy controls (NC) and patients with a diagnosis of probable Alzheimer's disease (AD) and mild cognitive impairment (MCI), and consequently results in better motor performance. Approximately half of the subjects in the NC (n = 31), AD (n = 28), and MCI (n = 29) either received or did not receive practice on a task of fast and accurate arm movement with a digitizer. Changes in movement time (MT), movement smoothness (jerk), and percentage of primary submovement (PPS) were recorded and compared among the three groups across six blocks of trials (baseline and five training sessions). For all subjects, practice improved motor functions as reflected by faster and smoother motor execution, as well as a greater proportion of programming control. Compared to unaffected matched controls, AD and MCI subjects exhibited a greater reduction in movement jerk due to practice. Movement time and PPS data revealed that motor practice appeared to reduce the use of “on-line” correction adopted by the AD or MCI patients while performing the aiming movements. Evidently, their arm movements were quicker, smoother, and temporally more consistent than their untrained peers. The findings of this study shed light on how MCI and AD may affect motor control mechanisms, and suggest possible therapeutic interventions aimed at improving motor functioning in these impaired individuals.     

Refractoriness in same-different judgments

Subjects judged as “same” or “different” pairs of visual stimuli, each either an X or an O, whose onsets were separated by intervals of 50, 100, 150 or 200 ms. When the interstimulus interval (ISI) was held constant within a block of 40 trials (Experiment I), decision time was independent of ISI. But when ISI was varied unpredictably from trial to trial (Experiments II and III), decision times increased the shorter the ISI. This effect was more marked for “same” than for “different” decisions. These results fail to support a single-channel interpretation, but suggest that variations in decision time depend on the subject's expectancy as to when the second stimulus will follow the first.     

The degree of stability in motor performance in preschool children and its association with child-related variables

Understanding the stability of individual differences in motor performance during the early years of life, despite normative age-related growth in motor performance, has important implications for identification of motor coordination difficulties and subsequently, early remediation. Therefore, the aims of the present study were to examine the degree of rank-order and individual-level stability in motor performance in young children with different levels of motor skill proficiency. Subsequently, we explored the influence of child variables (i.e., age, gender, and behavioural self-regulation) on different aspects of stability. In this longitudinal study, a community sample of 68 participants (49% girls) with a mean age of 3 years and 11 months (SD = 7 months) were assesses in three six-monthly waves. The total standard score of the Movement Assessment Battery for Children-2 (MABC-2) was used as the measure of motor performance. Rank-order stability was examined with zero-order Pearson correlations. Individual-level stability was examined by means of stability in classifications (at risk for motor coordination difficulties versus typically developing). In addition to examining stability in group classification, the Reliable Change Index (RCI) was calculated to examine if the difference in a child's scores over time exceeded (increased or decreased relative to) the expected change. The results showed moderate to high rank-order stability between time points. No significant differences in degree of rank-order stability were found between boys and girls and between 3-year old and 4-year old children. In terms of stability of classification, it was shown that for ~50% of the children with motor coordination difficulties and ~ 90% of typically developing the classification based on the cut-off score on the MABC-2 was stable. Based on the RCI, over 90% showed individual-level stability. The level of behavioural self-regulation at T1 (as measured with the Head-Toes-Knees-Shoulders task) was not significantly related to individual-level stability in motor performance. In conclusion, our findings highlight the importance of a careful choice of stability measures and a reflection on the implications of their results. More research is needed to understand which child and environmental variables impact on stability.