Feasibility and acceptability of an exergame intervention for schizophrenia

ObjectivesTo evaluate the feasibility and acceptability of an exergame intervention as a tool to promote physical activity in outpatients with schizophrenia.DesignFeasibility/Acceptability Study and Quasi-Experimental Trial.MethodSixteen outpatients with schizophrenia received treatment as usual and they all completed an 8-week exergame intervention using Microsoft Kinect^® (20 min sessions, biweekly). Participants completed pre and post treatment assessments regarding functional mobility (Timed Up and Go Test), functional fitness performance (Senior Fitness Test), motor neurological soft signs (Brief Motor Scale), hand grip strength (digital dynamometer), static balance (force plate), speed of processing (Trail Making Test), schizophrenia-related symptoms (Positive and Negative Syndrome Scale) and functioning (Personal and Social Performance Scale). The EG group completed an acceptability questionnaire after the intervention.ResultsAttrition rate was 18.75% and 69.23% of the participants completed the intervention within the proposed schedule. Baseline clinical traits were not related to game performance indicators. Over 90% of the participants rated the intervention as satisfactory and interactive. Most participants (76.9%) agreed that this intervention promotes healthier lifestyles and is an acceptable alternative to perform physical activity. Repeated-measures MANOVA analyses found no significant multivariate effects for combined outcomes.ConclusionThis study established the feasibility and acceptability of an exergame intervention for outpatients with schizophrenia. The intervention proved to be an appealing alternative to physical activity. Future trials should include larger sample sizes, explore patients' adherence to home-based exergames and consider greater intervention dosage (length, session duration, and/or frequency) in order to achieve potential effects.     

驾驶员在交通场景中的变化视盲及其启示

变化视盲(change blindness)现象,也称变化盲,是指视觉情景中人们不能觉察到某个事物变化的现象。研究以驾驶员为主体探讨了道路交通领域中的变化视盲现象。首先,从场景变化特征和驾驶员特征两个方面综述了影响驾驶员变化视盲的影响因素;其次,结合影响因素与变化视盲的特征理论建立了驾驶员变化检测的认知过程模型;最后,在模型的基础上,讨论了提高驾驶员变化检测能力的实际意义和潜在措施,并对未来有关交通安全变化视盲的研究予以展望。     

Measurement of functional task difficulty during motor learning: What level of difficulty corresponds to the optimal challenge point?

The relationship between task difficulty and learning benefit was examined, as was the measurability of task difficulty. Participants were required to learn a postural control task on an unstable surface at one of four different task difficulty levels. Results from the retention test showed an inverted-U relationship between task difficulty during acquisition and motor learning. The second-highest level of task difficulty was the most effective for motor learning, while learning was delayed at the most and least difficult levels. Additionally, the results indicate that salivary α-amylase and the performance dimension of the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) are useful indices of task difficulty. Our findings suggested that instructors may be able to adjust task difficulty based on salivary α-amylase and the performance dimension of the NASA-TLX to enhance learning.     

Further evidence of the heterogeneous nature of impulsivity

‘Impulsivity’ refers to a range of behaviours including preference for immediate reward (temporal-impulsivity) and the tendency to make premature decisions (reflection-impulsivity) and responses (motor-impulsivity). The current study aimed to examine how different behavioural and self-report measurements of impulsivity can be categorised into distinct subtypes.Exploratory factor analysis using full information maximum likelihood was conducted on 10 behavioural and 1 self-report measure of impulsivity.Four factors of impulsivity were indicated, with Factor 1 having a high loading of the Stop Signal Task, which measures motor-impulsivity, factor 2 representing reflection-impulsivity with loadings of the Information Sampling Task and Matching Familiar Figures Task, factor 3 representing the Immediate Memory Task, and finally factor 4 which represents the Delay Discounting Questionnaire and The Monetary Choice Questionnaire, measurements of temporal-impulsivity.These findings indicated that impulsivity is not a unitary construct, and instead represents a series of independent subtypes. There was evidence of a distinct reflection-impulsivity factor, providing the first factor analysis support for this subtype. There was also support for additional factors of motor- and temporal-impulsivity. The present findings indicated that a number of currently accepted tasks cannot be considered as indexing motor- and temporal-impulsivity suggesting that additional characterisations of impulsivity may be required.     

Attitudes,norms and driving behaviour: A comparison of young drivers in South Africa and Sweden

Culture is increasingly recognised among traffic psychologists to be a factor influencing driving behaviour. This study examines whether a cultural background characterised by rapid social change and high levels of violence and aggression, as in the South African context, has any discernible influences on driving standards or the behaviour of individual drivers. The experiences and attitudes of young drivers in South Africa are compared with a group of young drivers from Sweden, a country whose society has exhibited high levels of stability and where road user behaviour is renowned for its restraint and compliance with regulations.The two cohorts provide information about their exposure to traffic injuries, their attitudes to other drivers and to a range of traffic offences, and to the types of behaviour they personally engage in. Among the South African respondents the notion of a declining standard of driving emerges very clearly, and specific new norms of driving are identified. Such norms are explained to be a consequence of new social values or challenges inherent within contemporary South African society.     

Efficacy of proxy definitions for identification of fatigue/sleep-related crashes: An Australian evaluation

Fatigue/sleepiness is recognised as an important contributory factor in fatal and serious injury road traffic incidents (RTIs), however, identifying fatigue/sleepiness as a causal factor remains an uncertain science. Within Australia attending police officers at a RTI report the causal factors; one option is fatigue/sleepiness. In some Australian jurisdictions police incident databases are subject to post hoc analysis using a proxy definition for fatigue/sleepiness. This secondary analysis identifies further RTIs caused by fatigue/sleepiness not initially identified by attending officers. The current study investigates the efficacy of such proxy definitions for attributing fatigue/sleepiness as a RTI causal factor. Over 1600 Australian drivers were surveyed regarding their experience and involvement in fatigue/sleep-related RTIs and near-misses during the past five years. Driving while fatigued/sleepy had been experienced by the majority of participants (66.0% of participants). Fatigue/sleep-related near misses were reported by 19.1% of participants, with 2.4% being involved in a fatigue/sleep-related RTI. Examination of the characteristics for the most recent event (either a near miss or crash) found that the largest proportion of incidents (28.0%) occurred when commuting to or from work, followed by social activities (25.1%), holiday travel (19.8%), or for work purposes (10.1%). The fatigue/sleep related RTI and near-miss experience of a representative sample of Australian drivers does not reflect the proxy definitions used for fatigue/sleepiness identification. In particular those RTIs that occur in urban areas and at slow speeds may not be identified. While important to have a strategy for identifying fatigue/sleepiness related RTIs proxy measures appear best suited to identifying specific subsets of such RTIs.     

Muscle fatigue as an investigative tool in motor control: A review with new insights on internal models and posture–movement coordination

Muscle fatigue is a common phenomenon experienced in everyday life which affects both our force capacity and movement production. In this paper, we review works dealing with muscle fatigue and motor control and we attempt to demonstrate how the Central Nervous System deals with this particular state. We especially focus on how internal models – neural substrates which can estimate the current state as well as the future state of the body – face this internal perturbation. Moreover, we show that muscle fatigue is an interesting investigative tool in understanding the mechanisms involved in posture–movement coordination.     

Dealing with Possible Baseline Inequalities Between Experimental Groups – The Case of Motor Learning

Abstract

One important concept of experimental design is the random assignment of participants to experimental groups. This randomization process is used to prevent selection bias, as well as to provide a strong basis for a cause-and-effect relationship between the independent variable/s and the dependent variable/s. In small sample sizes, simple randomization may not provide equal groups at baseline for one or more of the variables, and therefore more restricted types of randomization, such as the stratified permuted-block randomization, can be used. A code was written to calculate the probability that simple randomization will not lead to equality between groups at baseline, and then an example of stratified permuted-block randomization was examined. The findings suggest that for certain variables that are commonly measured in experiments in motor learning, there is a relatively high probability that groups will not be equal at baseline after simple randomization. This observation reflects the small sample sizes usually found in the literature on motor learning. However, stratified permuted-block randomization does lead to greater equality among groups. Implications for researchers are discussed, and a flowchart is proposed that will allow researchers to decide whether to use simple or stratified randomization.     

The intelligent reflex

ABSTRACT

The seeming distinction between motor and cognitive skills has hinged on the fact that the former are automatic and non-propositional (knowing-how), whereas the latter are slow and deliberative (knowing-that). Here, the physiological and behavioral phenomenon of long-latency stretch reflexes is used to show that “knowing-that” can be incorporated into “knowing-how,” either immediately or through learning. The experimental demonstration that slow computations can, with practice, be cached for fast retrieval, without the need for re-computation, dissolves the intellectualist/anti-intellectualist distinction: All complex human tasks, at any level of expertise, are a combination of intelligent reflexes and deliberative decisions.     

Sleep dependent consolidation of gross motor sequence learning with motor imagery

Acquisition of gross motor sequence learning with physical and mental training elicits gains in performance. However, the effects of sleep or daytime consolidation after both types of practice remain unclear, especially the effects upon the goal- and movement-based components of a gross motor sequential task. The main purpose of this study was to test the effect of physical practice (PP) and motor imagery practice (MIP) on the acquisition and consolidation processes of gross motor sequence learning.Seventy-six participants were tested before and after PP or MIP on a whole-body sequential paradigm, following either a night of sleep (PP_sleep and MIP_sleep groups) or an equivalent daytime period (PP_day and MIP_day groups). Control groups without training were tested following similar timespans (CTRL_sleep and CTRL_day groups). The number of sequential movements and the centre of mass displacement – corresponding to goal and movement-based components, respectively – were assessed.Results showed that relative to the CTRL groups, the PP and MIP groups improved performance during acquisition. Importantly, only the MIP_sleep group further improved performance after a night of sleep; participants of other groups stabilised their performance after consolidation. Additionally, the number of sequential movements and the centre of mass displacement evolved conjointly without being influenced by the type of training or the nature of the consolidation.To conclude, these results confirm that sleep contributes to the consolidation of gross motor sequence learning acquired with MIP but not PP. The relationship between the goal- and movement-based components of a gross motor sequential task is discussed.