The influence of cognitive resources on compensatory arm responses

The purpose of this study was to determine the influence of an ongoing cognitive task on an individual’s ability to generate a compensatory arm response. Twenty young and 16 older adults recovered their balance from a support surface translation while completing a cognitive (counting) task of varying difficulty. Surface electromyographic (EMG) recordings from the shoulders and kinematics of the right arm were collected to quantify the compensatory arm response. Results indicated that the counting task, regardless of its difficulty as well as the age of the individual, had minimal influence on the onset or magnitude of arm muscle activity that occurred following a loss of balance. In contrast to previous research, this study’s findings suggest that the cortical or cognitive resources utilized by the cognitive task are not relied upon for the generation of compensatory arm responses and that older adults are not disproportionately affected by dual-tasking than young adults.

Development of an instrument for the analysis of problem gambling counselling practice

This article provides an overview of the development and validation of a Counsellor Task Analysis (Problem Gambling) [CTA (PG)] instrument undertaken in order to document the activities of counsellors in problem gambling services. The CTA (PG) aims to provide a broad overview of the complexity of the counsellor's role; specify the range of tasks they perform; and document the relationship between the frequency of task performance and the counsellor's beliefs about the importance of the tasks performed.

The CTA (PG) instrument addresses nine dimensions of practice activity through nine subscales, all of which demonstrate internal consistency. It appears to be a strong instrument in terms of its measurement error characteristics for recommending its use with counsellors engaged in the field of gambling. The CTA (PG) gives counsellors the opportunity to document their practice and theories in use when dealing with a problem gambler, a member of the problem gambler's family and the community at large. The psychometric findings reported in this article should be viewed as the preliminary results of an ongoing research effort and further psychometric testing is anticipated.

Subjective job task analyses for physically demanding occupations : what is best practice?

Workers in physically demanding occupations (PDOs) are frequently subjected to physical selection tests. To avoid legal ramifications, workplaces must be able to show that any personnel selection procedures reflect the inherent requirements of the job. A job task analysis (JTA) is fundamental in determining the work tasks required for employees. To date, there are no published instructions guiding PDO researchers on how to conduct job task analyses. Job task analysis research for non-PDOs offers some insight into the expected reliability and validity of data obtained on the most prevalent task domains in job analysis (importance, frequency, time spent and difficulty). This review critiques such research, and the existing published material on JTA of PDOs, and provides recommendations for future research and practice.

Investigação da relação entre conteúdo onírico e aprendizado de uma tarefa cognitiva complexa

Several lines of evidence indicate that sleep is beneficial for learning, but there is no experimental evidence yet that the content of dreams is adaptive, i.e., that dreams help the dreamer to cope with challenges of the following day. Our aim here is to investigate the role of dreams in the acquisition of a complex cognitive task. We investigated electroencephalographic recordings and dream reports of adult subjects exposed to a computer game comprising perceptual, motor, spatial, emotional and higher-level cognitive aspects (Doom). Subjects slept two nights in the sleep laboratory, a completely dark room with a comfortable bed and controlled temperature. Electroencephalographic recordings with 28 channels were continuously performed throughout the experiment to identify episodes of rapid-eye-movement (REM) sleep. Behaviors were continuously recorded in audio and video with an infrared camera. Dream reports were collected upon forced awakening from late REM sleep, and again in the morning after spontaneous awakening. On day 1, subjects were habituated to the sleep laboratory, no computer game was played, and negative controls for gamerelated dream reports were collected. On day 2, subjects played the computer game before and after sleep. Each game session lasted for an hour, and sleep for 7-9 hours. 9 different measures of performance indicated significant improve overnight. 81% of the subjects experienced intrusion of elements of the game into their dreams, including potentially adaptative strategies (insights). There was a linear correlation between performance and dream intrusion as well as for game improval and quantity of reported dreaming. In the electrophysiological analysis we mapped the subjects brain activities in different stages (SWS 1, REM 1, SWS 2, REM 2, Game 1 and Game 2), and found a modest reverberation in motor areas related to the joystick control during the sleep. When separated by gender, we found a significant difference on female subjects in the channels that indicate motor learning. Analysis of dream reports showed that the amount of gamerelated elements in dreams correlated with performance gains according to an inverted-U function analogous to the Yerkes-Dodson law that governs the relationship between arousal and learning. The results indicate that dreaming is an adaptive behavior

Multimodal exercise intervention improves frontal cognitive functions and gait in Alzheimer's disease: A controlled trial

Aim: The objective of the present study was to investigate the effect of a multimodal exercise intervention on frontal cognitive functions and kinematic gait parameters in patients with Alzheimer's disease. Methods: A sample of elderly patients with Alzheimer's disease (n=27) were assigned to a training group (n=14; aged 78.0±7.3years) and a control group (n=13; aged 77.1±7.4years). Multimodal exercise intervention includes motor activities and cognitive tasks simultaneously. The participants attended a 1-h session three times a week for 16weeks, and the control participants maintained their regular daily activities during the same period. The frontal cognitive functions were evaluated using the Frontal Assessment Battery, the Clock Drawing Test and the Symbol Search Subtest. The kinematic parameters of gait-cadence, stride length and stride speed were analyzed under two conditions: (i) free gait (single task); and (ii) gait with frontal cognitive task (walking and counting down from 20 - dual task). Results and discussion: The patients in the intervention group significantly increased the scores in frontal cognitive variables, Frontal Assessment Battery (P<0.001) and Symbol Search Subtest (P<0.001) after the 16-week period. The control group decreased the scores in the Clock Drawing Test (P=0.001) and increased the number of counting errors during the dual task (P=0.008) after the same period. Conclusion: The multimodal exercise intervention improved the frontal cognitive functions in patients with Alzheimer's disease. © 2012 Japan Geriatrics Society.

A interferência da tarefa dupla, motora e cognitiva, no andar de pacientes com doença de Parkinson

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Atividade física e funções cognitivas frontais associadas aos parâmetros cinemáticos da marcha em pacientes com demência de Alzheimer

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Funções cognitivas frontais e controle postural na doença de Alzheimer: efeitos do programa de intervenção motora com tarefa dupla

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Lower limb muscle coactivation levels in healthy younger and older adults during functional dual-task gait

The purpose of this study was to investigate the influence of daily cognitive task on stiffness of old and young female adults during the gait. The study included 17 physically active younger and 18 older women, with low risk of falls. The volunteers were asked to walk on the treadmill at two different gait conditions: normal gait and functional dual-task gait. The electromyographic signals were collected of the lower limb muscles. The percentage of coactivation for the tibialis anterior/gastrocnemius lateralis and tibialis anterior/soleus were significantly higher in elderly than in younger in the normal gait and dual-task gait. Our results suggest that the elderly have a greater stiffness in the ankle joint during gait normal and daily dual task gait. Thus, we conclude that challenging cognitively situations during the gait may increase the risk of falls in this population.

Comparação dos parâmetros espaçotemporais da marcha durante a execução do TUG associado à dupla tarefa em adultos jovens

Introduction: Biomechanical analysis of gait can be used effectively to identify changes in movement patterns and functional decline. Objective: To analyze the effect of dual task on gait spatio-temporal variables. Methods: The sample was made up of 32 subjects of both genders aged between 18 and 25 years. The test Timed Up and Go was performed under two conditions: original form and associated with a cognitive task (verbalize backwards the months of the year). We evaluated the total execution time, number of steps, cadence, time spent to lift, average speed and variability of the step time. Results: Significant changes were observed with the addition of the cognitive task in many gait spatio-temporal variables analyzed. Conclusion: The tests showed that the increase of cognitive tasks during walking may lead to changes in the performance of this task.

Autismo: aspectos cognitivos, educacionais e neurobiológicos com base na análise dos livros Mundo singular: entenda o autismo e o Os gatos nunca mentem sobre o amor e na literatura especializada

The autism is a severe mental illness that involves psychological, social, educational and neurobiological aspects. The Education plays an important role in recovering, preserving and increasing the cognitive task of people with autism. There are several ways to observe a person with autism. Through the studying of cases, it is also possible to address issues of everyday life of the person with the illness, its cognitive issues and its obstacles of psychosocial involvement, as well as psychological aspects such as illness acknowledgement. Through specialized literature, it is possible to identify characteristics referring to the learning process and neurobiological components involved in the condition, such as brain activity disorder and genetic factors. The objectives of this paper are: from the analysis of two books: Unique World: comprehend the Autism (SILVA, A. B. B; GAIATO, M.B; REVELES, L.T) and The cats never lie about love (DILLON, J.), it is intended to describe cognitive and psychosocial aspects of the autism. Based on the specialized literature, the goal is to identify cognitive and neurobiological components in the illness. The methods that were used: analysis of the books Unique World: comprehend the Autism and The cats never lie about love to describe psychosocial and educational aspects of the autism; analysis of the specialized literature to identify clinical and neurobiological components of the illness, such as changes in brain activity, genetic factors or clinical evolution; and also details of the Education role in preserving the person with autism and his cognitive and emotional development. The study had the documentary research as reference for the methodological design, including book analysis and research in specialized literature. It is intended to deepen discussions about the Education roles related to the cognitive and neurobiological aspects of the autism

Cognitive neurorehabilitation based on interactive video technology

Cognitive impairment is the main cause of disability in developed societies. New interactive technologies help therapists in neurorehabilitation in order to increase patients’ autonomy and quality of life. This work proposes Interactive Video (IV) as a technology to develop cognitive rehabilitation tasks based on Activities of Daily Living (ADL). ADL cognitive task has been developed and integrated with eye-tracking technology for task interaction and patients’ performance monitoring.

The role of prefrontal cortex and posterior parietal cortex in task switching

Human ability to switch from one cognitive task to another involves both endogenous preparation without an external stimulus and exogenous adjustment in response to the external stimulus. In an event-related functional MRI study, participants performed pairs of two tasks that are either the same (task repetition) or different (task switch) from each other. On half of the trials, foreknowledge about task repetition or task switch was available. On the other half, it was not. Endogenous preparation seems to involve lateral prefrontal cortex (BA 46/45) and posterior parietal cortex (BA 40). During preparation, higher activation increases in inferior lateral prefrontal cortex and superior posterior parietal cortex were associated with foreknowledge than with no foreknowledge. Exogenous adjustment seems to involve superior prefrontal cortex (BA 8) and posterior parietal cortex (BA 39/40) in general. During a task switch with no foreknowledge, activations in these areas were relatively higher than during a task repetition with no foreknowledge. These results suggest that endogenous preparation and exogenous adjustment for a task switch may be independent processes involving different brain areas.

Unravelling the complexity of muscle impairment in chronic neck pain

Exercise interventions are deemed essential for the effective management of patients with neck pain. However, there has been a lack of consensus on optimal exercise prescription, which has resulted from a paucity of studies to quantify the precise nature of muscle impairment, in people with neck pain. This masterclass will present recent research from our laboratory, which has utilized surface electromyography to investigate cervical flexor muscle impairment in patients with chronic neck pain. This research has identified deficits in the motor control of the deep and superficial cervical flexor muscles in people with chronic neck pain, characterized by a delay in onset of neck muscle contraction associated with movement of the upper limb. In addition, people with neck pain demonstrate an altered pattern of muscle activation, which is characterized by reduced deep cervical flexor muscle activity during a low load cognitive task and increased activity of the superficial cervical flexor muscles during both cognitive tasks and functional activities. The results have demonstrated the complex, multifaceted nature of cervical muscle impairment, which exists in people with a history of neck pain. In turn, this has considerable implications for the rehabilitation of muscle function in people with neck pain disorders. (C) 2004 Elsevier Ltd. All rights reserved.

Air traffic controller reactions to computer assistance

The research was instigated by the Civil Aviation Authority (CAA) to examine the implications for air traffic controllers' (ATCO) job satisfaction of the possible introduction of systems incorporating computer-assisted decision making. Additional research objectives were to assess the possible costs of reductions in ATCO job satisfaction, and to recommend appropriate task allocation between ATCOs and computer for future systems design (Chapter 1). Following a review of the literature (Chapter 2) it is argued that existing approaches to systems and job design do not allow for a sufficiently early consideration of employee needs and satisfactions in the design of complex systems. The present research develops a methodology for assessing affective reactions to an existing system as a basis for making reommendations for future systems design (Chapter 3). The method required analysis of job content using two techniques: (a) task analysis (Chapter 4.1) and (b) the Job Diagnostic Survey (JDS). ATCOs' affective reactions to the several operational positions on which they work were investigated at three levels of detail: (a) Reactions to positions, obtained by ranking techniques (Chapter 4.2); (b) Reactions to job characteristics, obtained by use of JDS (Chapter 4.3); and (c) Reactions to tasks, obtained by use of Repertory Grid technique (Chapter 4.4). The conclusion is drawn that ATCOs' motivation and satisfaction is greatly dependent on the presence of challenge, often through tasks requiring the use of decision making and other cognitive skills. Results suggest that the introduction of systems incorporating computer-assisted decision making might result in financial penalties for the CAA and significant reductions in job satisfaction for ATCOs. General recommendations are made for allocation of tasks in future systems design (Chapter 5).