An experimentally confirmed statistical model on arm movement

The purpose of this research work was to develop a methodology to model arm movement in normal subjects and neurologically impaired individuals through the application of a statistical modelling method. Thirteen subjects with Parkinson's disease and 29 normal controls were recruited to participate in an arm motor task. An infrared optoelectronic kinematic movement analysis system was employed to record arm movement at 50 times per second. This study identified the modified extended Freundlich model as one that could be used to describe this task. Results showed that this model fit the data well and that it has a good correspondence between the observed and the predicted data. However, verification of the model showed that the residuals contained a sizeable autocorrelation factor. The Cochrane and Orcutt method was applied to remove this factor, which improved the fit of the model. Results showed that Parkinson's disease subjects had a higher autocorrelation coefficient than the normal subjects for this task. A positive correlation (r(s) = 0.72, p < 0.001) was found between the Langton-Hewer stage and the autocorrelation coefficient of PD subjects. This finding suggests that if autocorrelation is positively correlated with disease progression, clinicians in their clinical practice might use the autocorrelation value as a useful indicator to quantify the progression of a subjects' disease. Significant differences in model parameters were seen between normal and Parkinson's disease subjects. The use of such a model to represent and quantify movement patterns provides an important base for future study.     

Challenges in implementing evidence-based treatment practices for co-occurring disorders in the criminal justice system

The presence of adults with mental health and substance abuse disorders within the criminal justice system has become increasingly evident over the past decade. Interventions and treatment services have been designed and research conducted in an effort to establish evidence-based practices that effectively address the complex needs of this population. However, adopting and implementing these evidence-based interventions and practices within the real-world setting of criminal justice environments is challenging. This article reviews the research literature related to evidence-based treatment practices for offenders with co-occurring mental health and substance abuse disorders and explores the inherent challenges of fitting these interventions and services within criminal justice settings.     

Nonnaïveté among Amazon Mechanical Turk workers: Consequences and solutions for behavioral researchers

Crowdsourcing services—particularly Amazon Mechanical Turk—have made it easy for behavioral scientists to recruit research participants. However, researchers have overlooked crucial differences between crowdsourcing and traditional recruitment methods that provide unique opportunities and challenges. We show that crowdsourced workers are likely to participate across multiple related experiments and that researchers are overzealous in the exclusion of research participants. We describe how both of these problems can be avoided using advanced interface features that also allow prescreening and longitudinal data collection. Using these techniques can minimize the effects of previously ignored drawbacks and expand the scope of crowdsourcing as a tool for psychological research.     

Wittgenstein on the Resurrection

Wittgenstein probably did not believe in Christ's Resurrection (as an historical event), but he may well have believed that if he had achieved a higher level of devoutness he would believe it. His view seems to have been that devout Christians are right in holding onto this belief tenaciously even though, in fact, it's false. It's historical falsity, is compatible with its religious validity, so to speak. So far as I can see, he did not think that devout Christians should believe that it doesn't really matter whether or not that alleged historical event occurred.     

The effects of transcranial direct current stimulation (tDCS) on multitasking performance and oculometrics

Multitasking is the ability to perform more than one task simultaneously. The need to multitask is common in many industries especially within the military with tasks such as air traffic controllers, cyber defense operators and image analysts. However, as the time on task increases, information throughput can become overwhelming resulting in a performance decrement. Through task prioritizing, the operator is able to maintain performance on specific subtasks in which they selected as high importance while other subtasks experience a decrement. The objective of this study was to evaluate the effects of transcranial direct current stimulation (tDCS) applied to the left dorsolateral prefrontal cortex (ldLPFC) on information processing capabilities to improve individual and overall multitasking performance while performing the multi-attribute task battery (MATB). Two groups of 8 participants each received either 2 mA of anodal or sham tDCS while performing MATB. In addition, eye tracking was implemented to record eye movement patterns. In doing so, we were able to determine how much time the operator allocated to each of the subtasks within MATB and how their task priorities changed as workload demands increased. The findings provided evidence that 2 mA of anodal tDCS during MATB significantly improved overall information throughput compared to the sham group. With respect to the individual subtasks, communication and system monitoring displayed the greatest enhancement with anodal tDCS. Our data suggests that tDCS could be a useful tool to enhance information processing capabilities during a multitasking paradigm resulting in improved processing capabilities and information throughput.     

When auditory presentations should and should not be a component of multimedia instruction

Based on cognitive load theory, two experiments investigated the conditions under which audiovisual‐based instruction may be an effective or an ineffective instructional technique. Results from Experiment 1 indicated that visual with audio presentations were superior to equivalent visual‐only presentations. In this experiment, neither the auditory nor the visual material could be understood in isolation. Both sources of information were interrelated and were essential to render the material intelligible. In contrast, Experiment 2 demonstrated that a non‐essential explanatory text, presented aurally with similar written text contained in a diagram, hindered learning. This result was obtained because when compared to a diagram only format, the aural material was unnecessary and therefore created a redundancy effect. Differences between groups were stronger when information was high in complexity. It was concluded that the effectiveness of multimedia instruction depends very much on how and when auditory information is used. Copyright © 2003 John Wiley & Sons, Ltd.