Pavlovian reward learning underlies value driven attentional capture.

PubMed

Bucker, Berno; Theeuwes, Jan

2017-02-01

Recent evidence shows that distractors that signal high compared to low reward availability elicit stronger attentional capture, even when this is detrimental for task-performance. This suggests that simply correlating stimuli with reward administration, rather than their instrumental relationship with obtaining reward, produces value-driven attentional capture. However, in previous studies, reward delivery was never response independent, as only correct responses were rewarded, nor was it completely task-irrelevant, as the distractor signaled the magnitude of reward that could be earned on that trial. In two experiments, we ensured that associative reward learning was completely response independent by letting participants perform a task at fixation, while high and low rewards were automatically administered following the presentation of task-irrelevant colored stimuli in the periphery (Experiment 1) or at fixation (Experiment 2). In a following non-reward test phase, using the additional singleton paradigm, the previously reward signaling stimuli were presented as distractors to assess truly task-irrelevant value driven attentional capture. The results showed that high compared to low reward-value associated distractors impaired performance, and thus captured attention more strongly. This suggests that genuine Pavlovian conditioning of stimulus-reward contingencies is sufficient to obtain value-driven attentional capture. Furthermore, value-driven attentional capture can occur following associative reward learning of temporally and spatially task-irrelevant distractors that signal the magnitude of available reward (Experiment 1), and is independent of training spatial shifts of attention towards the reward signaling stimuli (Experiment 2). This confirms and strengthens the idea that Pavlovian reward learning underlies value driven attentional capture.

A comparison of conscious and automatic memory processes for picture and word stimuli: a process dissociation analysis.

PubMed

McBride, Dawn M; Anne Dosher, Barbara

2002-09-01

Four experiments were conducted to evaluate explanations of picture superiority effects previously found for several tasks. In a process dissociation procedure (Jacoby, 1991) with word stem completion, picture fragment completion, and category production tasks, conscious and automatic memory processes were compared for studied pictures and words with an independent retrieval model and a generate-source model. The predictions of a transfer appropriate processing account of picture superiority were tested and validated in "process pure" latent measures of conscious and unconscious, or automatic and source, memory processes. Results from both model fits verified that pictures had a conceptual (conscious/source) processing advantage over words for all tasks. The effects of perceptual (automatic/word generation) compatibility depended on task type, with pictorial tasks favoring pictures and linguistic tasks favoring words. Results show support for an explanation of the picture superiority effect that involves an interaction of encoding and retrieval processes.

Self-Reinforcement Compared to Teacher-Delivered Reinforcement during Activity Schedules on the iPod Touch

ERIC Educational Resources Information Center

Beaver, Brittany N.; Reeve, Sharon A.; Reeve, Kenneth F.; DeBar, Ruth M.

2017-01-01

The current study assessed whether four 15- to 17-year-old individuals diagnosed with autism would remain on-task for more intervals and complete tasks independently as a function of using self-reinforcement or teacher-delivered reinforcement. An adapted alternating-treatments design with teacher-delivered reinforcement, self-reinforcement, and a…

Detection of Acute and Long-Term Effects of Concussion: Dual-Task Gait Balance Control Versus Computerized Neurocognitive Test.

PubMed

Howell, David R; Osternig, Louis R; Chou, Li-Shan

2018-02-16

To examine the acute (within 72h of injury) and long-term (2mo postinjury) independent associations between objective dual-task gait balance and neurocognitive measurements among adolescents and young adults with a concussion and matched controls. Longitudinal case-control. Motion analysis laboratory. A total of 95 participants completed the study: 51 who sustained a concussion (mean age, 17.5±3.3y; 71% men) and 44 controls (mean age, 17.7±2.9y; 72% men). Participants who sustained a concussion underwent a dual-task gait analysis and computerized neurocognitive testing within 72 hours of injury and again 2 months later. Uninjured controls also completed the same test protocol in similar time increments. Not applicable. We compared dual-task gait balance control and computerized neurocognitive test performance between groups using independent samples t tests. Multivariable binary logistic regression models were then constructed for each testing time to determine the association between group membership (concussion vs control), dual-task gait balance control, and neurocognitive function. Medial-lateral center-of-mass displacement during dual-task gait was independently associated with group membership at the initial test (adjusted odds ratio [aOR], 2.432; 95% confidence interval [CI], 1.269-4.661) and 2-month follow-up test (aOR, 1.817; 95% CI, 1.014-3.256) tests. Visual memory composite scores were significantly associated with group membership at the initial hour postinjury time point (aOR, .953; 95% CI, .833-.998). However, the combination of computerized neurocognitive test variables did not predict dual-task gait balance control for participants with concussion, and no single neurocognitive variable was associated with dual-task gait balance control at either testing time. Dual-task assessments concurrently evaluating gait and cognitive performance may allow for the detection of persistent deficits beyond those detected by computerized neurocognitive deficits alone. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

TWIICE - A lightweight lower-limb exoskeleton for complete paraplegics.

PubMed

Vouga, Tristan; Baud, Romain; Fasola, Jemina; Bouri, Mohamed; Bleuler, Hannes

2017-07-01

This paper introduces TWIICE, a lower-limb exoskeleton that enables people suffering from complete paraplegia to stand up and walk again. TWIICE provides complete mobilization of the lower-limbs, which is a first step toward enabling the user to regain independence in activities of the daily living. The tasks it can perform include level and inclined walking (up to 20° slope), stairs ascent and descent, sitting on a seat, and standing up. Participation in the world's first Cybathlon (Zurich, 2016) demonstrated good performance at these demanding tasks. In this paper, we describe the implementation details of the device and comment on preliminary results from a single user case study.

Performance Evaluation of a Mobile Touchscreen Interface for Assistive Robotic Manipulators: A Pilot Study.

PubMed

Chung, Cheng-Shiu; Ka, Hyun W; Wang, Hongu; Ding, Dan; Kelleher, Annmarie; Cooper, Rory A

2017-01-01

Background: Assistive robotic manipulators (ARMs) have been developed to provide enhanced assistance and independence in performance of daily activities among people with spinal cord injury when a caregiver is not on site. However, the current commercial ARM user interfaces (UIs) may be difficult to learn and control. A touchscreen mobile UI was developed to overcome these challenges. Objective: The object of this study was to evaluate the performance between 2 ARM UIs, touchscreen and the original joystick, using an ARM evaluation tool (ARMET). Methods: This is a pilot study of people with upper extremity impairments ( N = 8). Participants were trained on 2 UIs, and then they chose one to use when performing 3 tasks on the ARMET: flipping a toggle switch, pushing down a door handle, and turning a knob. Task completion time, mean velocity, and open interviews were the main outcome measurements. Results: Among 8 novice participants, 7 chose the touchscreen UI and 1 chose the joystick UI. All participants could complete the ARMET tasks independently. Use of the touchscreen UI resulted in enhanced ARMET performance (higher mean moving speed and faster task completion). Conclusions: Mobile ARM UIs demonstrated easier learning experience, less physical effort, and better ARMET performance. The improved performance, the accessibility, and lower physical effort suggested that the touchscreen UI might be an efficient tool for the ARM users.

Considering student choice when selecting instructional strategies: a comparison of three prompting systems.

PubMed

Taber-Doughty, Teresa

2005-01-01

Three secondary age students with moderate intellectual disabilities learned to use the system of least prompts, a self-operated picture prompting system, and a self-operated auditory prompting system to use a copy machine and a debit machine. Both the effectiveness and efficiency of these prompting systems were compared. Additionally, student preference of instructional method was examined. The results demonstrated that each prompting system was effective and efficient with varying students when skill acquisition and duration of task performance were measured. All students demonstrated increased independence in completing both tasks. This study found that the preferred prompting systems were more effective in terms of both skill acquisition and duration for completing tasks for students.

Medical telementoring using an augmented reality transparent display.

PubMed

Andersen, Daniel; Popescu, Voicu; Cabrera, Maria Eugenia; Shanghavi, Aditya; Gomez, Gerardo; Marley, Sherri; Mullis, Brian; Wachs, Juan P

2016-06-01

The goal of this study was to design and implement a novel surgical telementoring system called the System for Telementoring with Augmented Reality (STAR) that uses a virtual transparent display to convey precise locations in the operating field to a trainee surgeon. This system was compared with a conventional system based on a telestrator for surgical instruction. A telementoring system was developed and evaluated in a study which used a 1 × 2 between-subjects design with telementoring system, that is, STAR or conventional, as the independent variable. The participants in the study were 20 premedical or medical students who had no prior experience with telementoring. Each participant completed a task of port placement and a task of abdominal incision under telementoring using either the STAR or the conventional system. The metrics used to test performance when using the system were placement error, number of focus shifts, and time to task completion. When compared with the conventional system, participants using STAR completed the 2 tasks with less placement error (45% and 68%) and with fewer focus shifts (86% and 44%), but more slowly (19% for each task). Using STAR resulted in decreased annotation placement error, fewer focus shifts, but greater times to task completion. STAR placed virtual annotations directly onto the trainee surgeon's field of view of the operating field by conveying location with great accuracy; this technology helped to avoid shifts in focus, decreased depth perception, and enabled fine-tuning execution of the task to match telementored instruction, but led to greater times to task completion. Copyright © 2016 Elsevier Inc. All rights reserved.

Feasibility of using touch screen technology for early cognitive assessment in children.

PubMed

Twomey, Deirdre M; Wrigley, Conal; Ahearne, Caroline; Murphy, Raegan; De Haan, Michelle; Marlow, Neil; Murray, Deirdre M

2018-03-13

To explore the feasibility of using a touch screen assessment tool to measure cognitive capacity in toddlers. 112 typically developing children with a median age of 31 months (IQR: 26-34) interacted with a touch screen cognitive assessment tool. We examined the sensitivity of the tool to age-related changes in cognition by comparing the number of items completed, speed of task completion and accuracy in two age groups; 24-29 months versus 30-36 months. Children aged 30-36 months completed more tasks (median: 18, IQR: 18-18) than those aged 24-29 months (median: 17, IQR: 15-18). Older children also completed two of the three working memory tasks and an object permanence task faster than their younger peers. Children became faster at completing the working memory items with each exposure and registered similar completion times on the hidden object retrieval items, despite task demands being twofold on the second exposure. A novel item required children to integrate what they had learnt on preceding items. The older group was more likely to complete this item and to do so faster than the younger group. Children as young as 24 months can complete items requiring cognitive engagement on a touch screen device, with no verbal instruction and minimal child-administrator interaction. This paves the way for using touch screen technology for language and administrator independent developmental assessment in toddlers. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The Sentence Completion and Three Wishes tasks: windows into the inner lives of people with intellectual disabilities.

PubMed

Dykens, E; Schwenk, K; Maxwell, M; Myatt, B

2007-08-01

Measuring the self-perceptions, thoughts, hopes and inner lives of persons with intellectual disabilities (ID) has long been a research challenge. Unlike objective or projective tests, semi-projective tasks may provide persons with ID with just enough structure or cues to convey their self-perceptions in a spontaneous and unbiased manner. Sentence Completion and Three Wishes tasks were individually administered to 128 persons with ID aged 5-50 years (mean = 18.75 years). Participants had Prader-Willi, Williams or Down syndromes. Content analyses resulted in 19 codes that were used to reliably score both tasks by independent raters who achieved excellent levels of inter-rater agreement. Participants also received IQ testing, and their parents or care providers completed the Child Behavior Checklist (CBCL). Frequent themes across both tasks included activities, positive affect, desired objects, and relationships with family and pets. No gender or IQ effects were found, and just a few codes showed modest age effects. Several responses, including dating, friends, food, and positive or negative self-appraisals, were significantly related to either syndrome status or CBCL maladaptive behaviour. Although not widely used, the Sentence Completion and Three Wishes tasks are useful semi-projective techniques for garnering otherwise hard-to-access self-perceptions and associations of people with ID. Implications are discussed for practice and research.

The Effects of Automated Prompting and Self-Monitoring on Homework Completion for a Student with Attention Deficit Hyperactivity Disorder

ERIC Educational Resources Information Center

Blicha, Amy; Belfiore, Phillip J.

2013-01-01

This study examined the effects of an intervention consisting of automated prompting and self-monitoring on the level of independent homework task completion for an elementary-age student with attention deficit hyperactivity disorder (ADHD). Instituting a single subject, within series ABAB design, the results showed a consistent increase and…

Influence of cognitive style on information processing and selection of yogurt labels: Insights from an eye-tracking study.

PubMed

Mawad, Franco; Trías, Marcela; Giménez, Ana; Maiche, Alejandro; Ares, Gastón

2015-08-01

Cognitive styles are characteristic and stable ways in which people acquire, organize and use information for solving problems and making decisions. Field dependence/independence is one of the most studied cognitive styles. Field independent subjects are characterized by having less difficulty in separating information from its contextual surroundings and being less likely to be influenced by external cues than field dependent individuals. The present work aimed at studying the influence of field dependence/independence cognitive style on consumers' visual processing and choice of yogurt labels. One hundred and thirty three consumers completed a choice conjoint task. They were asked to select their preferred yogurt label from each of 16 pairs of labels. While they completed the task their eye movements were recorded using an eye-tracker. Then, consumers were asked to complete the Group Embedded Figure Test to determine their cognitive style. Consumers were divided into two groups with different cognitive styles: 58% of the sample was characterized as field dependent and 42% as field independent. When making their choices, field dependent consumers tended to engage in less thoughtful information processing than field independent consumers and they made fewer fixations on traditional nutritional information. Besides, cognitive style significantly affected the relative importance of fat and sugar content on consumer choices and modulated the influence of the traffic light system. Field dependent consumers gave less importance to the nutritional composition of the yogurts than field independent consumers for selecting their preferred label. Results from this work suggest that studying the psychological underpinnings of consumers' decision making process when selecting food products has a great potential to contribute to a better understanding of how eating patterns and consumer preferences are shaped. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of a Personal Digital Assistant as a Self-Prompting Device for Increasing Multi-Step Task Completion by Students with Moderate Intellectual Disabilities

ERIC Educational Resources Information Center

Mechling, Linda C.; Gast, David L.; Seid, Nicole H.

2010-01-01

The purpose of this study was to evaluate whether the use of a personal digital assistant (PDA), with picture, auditory, and video prompts, would serve as a portable self-prompting device to facilitate independent task performance by high school age students with moderate intellectual disabilities. A multiple probe design was used across three…

Cultural differences in distraction processing: influence of context at retrieval.

PubMed

Ngo, Ka Wai Joan; Amer, Tarek; Man, Louisa; Hasher, Lynn

2018-06-04

Cultural differences in information processing affect perceptual judgment, attention, and memory. We investigated whether cultural differences in processing patterns, specifically East Asian participants' tendency to encode holistically, compared to Western tendencies to process analytically, affect performance on an implicit memory test. First, participants completed a 1-back task on pictures with superimposed distracting words. After a delay filled with a computerised Corsi block task, they performed a word fragment task in which some fragments could be completed with the distracting words from the 1-back task. Critically, fragments were presented with the same pictures as previously seen (matched condition), with no pictures (control condition), or with pictures from other trials on the 1-back task (mismatched condition). Non-Asian Canadian participants showed virtually no priming for distraction, independent of the reinstatement of encoding context. East Asian Canadian participants showed superior priming for fragments that had been paired with their original pictures. They did not show evidence of a detriment for the mismatched, relative to control, condition.

Medication Reconciliation: Work Domain Ontology, prototype development, and a predictive model.

PubMed

Markowitz, Eliz; Bernstam, Elmer V; Herskovic, Jorge; Zhang, Jiajie; Shneiderman, Ben; Plaisant, Catherine; Johnson, Todd R

2011-01-01

Medication errors can result from administration inaccuracies at any point of care and are a major cause for concern. To develop a successful Medication Reconciliation (MR) tool, we believe it necessary to build a Work Domain Ontology (WDO) for the MR process. A WDO defines the explicit, abstract, implementation-independent description of the task by separating the task from work context, application technology, and cognitive architecture. We developed a prototype based upon the WDO and designed to adhere to standard principles of interface design. The prototype was compared to Legacy Health System's and Pre-Admission Medication List Builder MR tools via a Keystroke-Level Model analysis for three MR tasks. The analysis found the prototype requires the fewest mental operations, completes tasks in the fewest steps, and completes tasks in the least amount of time. Accordingly, we believe that developing a MR tool, based upon the WDO and user interface guidelines, improves user efficiency and reduces cognitive load.

Medication Reconciliation: Work Domain Ontology, Prototype Development, and a Predictive Model

PubMed Central

Markowitz, Eliz; Bernstam, Elmer V.; Herskovic, Jorge; Zhang, Jiajie; Shneiderman, Ben; Plaisant, Catherine; Johnson, Todd R.

2011-01-01

Medication errors can result from administration inaccuracies at any point of care and are a major cause for concern. To develop a successful Medication Reconciliation (MR) tool, we believe it necessary to build a Work Domain Ontology (WDO) for the MR process. A WDO defines the explicit, abstract, implementation-independent description of the task by separating the task from work context, application technology, and cognitive architecture. We developed a prototype based upon the WDO and designed to adhere to standard principles of interface design. The prototype was compared to Legacy Health System’s and Pre-Admission Medication List Builder MR tools via a Keystroke-Level Model analysis for three MR tasks. The analysis found the prototype requires the fewest mental operations, completes tasks in the fewest steps, and completes tasks in the least amount of time. Accordingly, we believe that developing a MR tool, based upon the WDO and user interface guidelines, improves user efficiency and reduces cognitive load. PMID:22195146

"Hunting with a knife and ... fork": examining central coherence in autism, attention deficit/hyperactivity disorder, and typical development with a linguistic task.

PubMed

Booth, Rhonda; Happé, Francesca

2010-12-01

A local processing bias, referred to as "weak central coherence," has been postulated to underlie key aspects of autism spectrum disorder (ASD). Little research has examined whether individual differences in this cognitive style can be found in typical development, independent of intelligence, and how local processing relates to executive control. We present a brief and easy-to-administer test of coherence requiring global sentence completions. We report results from three studies assessing (a) 176 typically developing (TD) 8- to 25-year-olds, (b) individuals with ASD and matched controls, and (c) matched groups with ASD or attention deficit/hyperactivity disorder (ADHD). The results suggest that the Sentence Completion Task can reveal individual differences in cognitive style unrelated to IQ in typical development, that most (but not all) people with ASD show weak coherence on this task, and that performance is not related to inhibitory control. The Sentence Completion Task was found to be a useful test instrument, capable of tapping local processing bias in a range of populations. (c) 2010 Elsevier Inc. All rights reserved.

PRISM: Enmeshment of illness and self-schema.

PubMed

Denton, Fiona; Sharpe, Louise; Schrieber, Leslie

2004-01-01

The Pictorial Representation of Illness and Self Measure (PRISM) is a recently developed tool purported to assess burden of suffering due to illness. The nature of the PRISM task suggests a conceptual link to the illness self-schema construct hypothesised to be present in some individuals with chronic illness. This study investigates the relationship between PRISM and schema as measured by cognitive bias. 43 patients with systemic lupus erythematosus (SLE) completed an information-processing task involving endorsement of positive and negative illness words as descriptors of themselves, followed by free recall of the words. The outcome measures were endorsement and recall bias for negative illness words. Patients also completed the PRISM task and were assessed on other physical and psychological variables. PRISM did not correlate significantly with age, depression, functional impairment or disease activity. In a multiple regression analysis, only recall bias made an independent contribution to PRISM. Illness self-schema appears to play a significant role in determining the way in which SLE patients complete the PRISM task. This is discussed in light of a schema enmeshment model recently proposed in the cognitive bias literature. Copyright 2004 S. Karger AG, Basel

The Effects of Self-Monitoring with a MotivAider[R] on the On-Task Behavior of Fifth and Sixth Graders with Autism and Other Disabilities

ERIC Educational Resources Information Center

Legge, Dina Boccuzzi; DeBar, Ruth M.; Alber-Morgan, Sheila R.

2010-01-01

This study examined the effects of self-monitoring on the on-task behavior of three fifth and sixth grade boys with autism and other disabilities. While completing math assignments independently, the students wore an electronic device called a MotivAider[R] that vibrated at pre-set time schedules prompting the students to self-record whether or…

The complete optical oscilloscope

NASA Astrophysics Data System (ADS)

Lei, Cheng; Goda, Keisuke

2018-04-01

Observing ultrafast transient dynamics in optics is a challenging task. Two teams in Europe have now independently developed `optical oscilloscopes' that can capture both amplitude and phase information of ultrafast optical signals. Their schemes yield new insights into the nonlinear physics that takes place inside optical fibres.

Performance evaluation of the Personal Mobility and Manipulation Appliance (PerMMA).

PubMed

Wang, Hongwu; Xu, Jijie; Grindle, Garrett; Vazquez, Juan; Salatin, Ben; Kelleher, Annmarie; Ding, Dan; Collins, Diane M; Cooper, Rory A

2013-11-01

The Personal Mobility and Manipulation Appliance (PerMMA) is a recently developed personal assistance robot created to provide people with severe physical disabilities enhanced assistance in both mobility and manipulation. PerMMA aims to improve functional independence when a personal care attendant is not available on site. PerMMA integrates both a smart powered wheelchair and two dexterous robotic arms to assist its users in completing essential mobility and manipulation tasks during basic and instrumental activities of daily living (ADL). Two user interfaces were developed: a local control interface and a remote operator controller. This paper reports on the evaluation of PerMMA with end users completing basic ADL tasks. Participants with both lower and upper extremity impairments (N=15) were recruited to operate PerMMA and complete up to five ADL tasks in a single session of no more than two hours (to avoid fatigue or frustration of the participants). The performance of PerMMA was evaluated by participants completing ADL tasks with two different control modes: local mode and cooperative control. The users' task completion performance and answers on pre/post-evaluation questionnaires demonstrated not only the ease in learning and usefulness of PerMMA, but also their attitudes toward assistance from advanced technology like PerMMA. As a part of the iterative development process, results of this work will serve as supporting evidence to identify design criteria and other areas for improvement of PerMMA. Copyright © 2013 IPEM. All rights reserved.

Usability of a CKD educational website targeted to patients and their family members.

PubMed

Diamantidis, Clarissa J; Zuckerman, Marni; Fink, Wanda; Hu, Peter; Yang, Shiming; Fink, Jeffrey C

2012-10-01

Web-based technology is critical to the future of healthcare. As part of the Safe Kidney Care cohort study evaluating patient safety in CKD, this study determined how effectively a representative sample of patients with CKD or family members could interpret and use the Safe Kidney Care website (www.safekidneycare.org), an informational website on safety in CKD. Between November of 2011 and January of 2012, persons with CKD or their family members underwent formal usability testing administered by a single interviewer with a second recording observer. Each participant was independently provided a list of 21 tasks to complete, with each task rated as either easily completed/noncritical error or critical error (user cannot complete the task without significant interviewer intervention). Twelve participants completed formal usability testing. Median completion time for all tasks was 17.5 minutes (range=10-44 minutes). In total, 10 participants had greater than or equal to one critical error. There were 55 critical errors in 252 tasks (22%), with the highest proportion of critical errors occurring when participants were asked to find information on treatments that may damage kidneys, find the website on the internet, increase font size, and scroll to the bottom of the webpage. Participants were generally satisfied with the content and usability of the website. Web-based educational materials for patients with CKD should target a wide range of computer literacy levels and anticipate variability in competency in use of the computer and internet.

Assessing performance of an Electronic Health Record (EHR) using Cognitive Task Analysis.

PubMed

Saitwal, Himali; Feng, Xuan; Walji, Muhammad; Patel, Vimla; Zhang, Jiajie

2010-07-01

Many Electronic Health Record (EHR) systems fail to provide user-friendly interfaces due to the lack of systematic consideration of human-centered computing issues. Such interfaces can be improved to provide easy to use, easy to learn, and error-resistant EHR systems to the users. To evaluate the usability of an EHR system and suggest areas of improvement in the user interface. The user interface of the AHLTA (Armed Forces Health Longitudinal Technology Application) was analyzed using the Cognitive Task Analysis (CTA) method called GOMS (Goals, Operators, Methods, and Selection rules) and an associated technique called KLM (Keystroke Level Model). The GOMS method was used to evaluate the AHLTA user interface by classifying each step of a given task into Mental (Internal) or Physical (External) operators. This analysis was performed by two analysts independently and the inter-rater reliability was computed to verify the reliability of the GOMS method. Further evaluation was performed using KLM to estimate the execution time required to perform the given task through application of its standard set of operators. The results are based on the analysis of 14 prototypical tasks performed by AHLTA users. The results show that on average a user needs to go through 106 steps to complete a task. To perform all 14 tasks, they would spend about 22 min (independent of system response time) for data entry, of which 11 min are spent on more effortful mental operators. The inter-rater reliability analysis performed for all 14 tasks was 0.8 (kappa), indicating good reliability of the method. This paper empirically reveals and identifies the following finding related to the performance of AHLTA: (1) large number of average total steps to complete common tasks, (2) high average execution time and (3) large percentage of mental operators. The user interface can be improved by reducing (a) the total number of steps and (b) the percentage of mental effort, required for the tasks. 2010 Elsevier Ireland Ltd. All rights reserved.

Aging Ebbs the Flow of Thought: Adult Age Differences in Mind Wandering, Executive Control, and Self-Evaluation

PubMed Central

McVay, Jennifer C.; Meier, Matthew E.; Touron, Dayna R.; Kane, Michael J.

2013-01-01

Two experiments examined the relations among adult aging, mind wandering, and executive-task performance, following from surprising laboratory findings that older adults report fewer task-unrelated thoughts (TUTs) than do younger adults (e.g., Giambra, 1989; Jackson & Balota, 2011). Because older adults may experience more ability- and performance-related worry during cognitive tasks in the laboratory, and because these evaluative thoughts (known as task-related interference, “TRI”) might be sometimes misclassified by subjects as task-related, we asked subjects to distinguish task-related thoughts from TRI and TUTs when probed during ongoing tasks. In Experiment 1, younger and older adults completed either a go/no-go or a vigilance version of a sustained attention to response task (SART). Older adults reported more TRI and fewer TUTs than did younger adults while also performing more accurately. In Experiment 2, subjects completed either a 1- or 2-back version of the n-back task. Older adults again reported more TRI and fewer TUTs than younger adults in both versions, while performing better than younger adults in the 1-back and worse in the 2-back. Across experiments, older adults’ reduced TUT rates were independent of performance relative to younger adults. And, although older adults consistently reported more TRI and less mind wandering than did younger adults, overall they reported more on-task thoughts. TRI cannot, therefore, account completely for prior reports of decreasing TUTs with aging. We discuss the implications of these results for various theoretical approaches to mind-wandering. PMID:23261422

Simulation-based intelligent robotic agent for Space Station Freedom

NASA Technical Reports Server (NTRS)

Biegl, Csaba A.; Springfield, James F.; Cook, George E.; Fernandez, Kenneth R.

1990-01-01

A robot control package is described which utilizes on-line structural simulation of robot manipulators and objects in their workspace. The model-based controller is interfaced with a high level agent-independent planner, which is responsible for the task-level planning of the robot's actions. Commands received from the agent-independent planner are refined and executed in the simulated workspace, and upon successful completion, they are transferred to the real manipulators.

Disposed to distraction: Genetic variation in the cholinergic system influences distractibility but not time-on-task effects

PubMed Central

Berry, Anne S.; Demeter, Elise; Sabhapathy, Surya; English, Brett A.; Blakely, Randy D.; Sarter, Martin; Lustig, Cindy

2015-01-01

Both the passage of time and external distraction make it difficult to keep attention on the task at hand. We tested the hypothesis that time-on-task and external distraction pose independent challenges to attention, and that the brain’s cholinergic system selectively modulates our ability to resist distraction. Participants with a polymorphism limiting cholinergic capacity (Ile89Val variant (rs1013940) of the choline transporter gene SLC5A7) and matched controls completed self-report measures of attention and a laboratory task that measured decrements in sustained attention with and without distraction. We found evidence that distraction and time-on-task effects are independent and that the cholinergic system is strongly linked to greater vulnerability to distraction. Ile89Val participants reported more distraction during everyday life than controls, and their task performance was more severely impacted by the presence of an ecologically valid video distractor (similar to a television playing in the background). These results are the first to demonstrate a specific impairment in cognitive control associated with the Ile89Val polymorphism, and add to behavioral and cognitive neuroscience studies indicating the cholinergic system’s critical role in overcoming distraction. PMID:24666128

Portable electronic assistive technology to improve vocational task completion in young adults with an intellectual disability.

PubMed

Collins, James C; Collet-Klingenberg, Lana

2017-01-01

This article summarizes a review of empirical literature from 2000 to 2015 that involved the use of specific portable technology to support persons with an intellectual disability in completing work-related tasks. Nineteen studies were identified for review, with an emphasis on the identification of (a) the characteristics of participants and settings, (b) the types of portable technology and prompting formats used, (c) the research designs utilized, (d) the independent and dependent variables, (e) the measures of reliability and validity, and (f) the overall effectiveness of the interventions. The authors provide an interpretation of the findings as well as the implications of the results and recommended areas for future research.

A study of performance assessment task organization in high school optics

NASA Astrophysics Data System (ADS)

Zawicki, Joseph Leo

2002-01-01

This investigation was undertaken to validate three performance assessment tasks in high school physics. The tasks that were studied were developed around three organizational models of performance assessments: integrated, independent and surrogate. The integrated model required students to answer questions, make observations and demonstrate skills related to the index of refraction of a particular material. All of the questions and activities the students completed were related to a sample of a particular plastic sample that was the focus of this task. The independent model is analogous to the station model that is currently used on three New York State assessments: the Grade 4 - Elementary Science Program Evaluation Test, the Intermediate Level Science (ILS) Test, and the Physical Setting: Earth Science Regents Exam. Students took measurements related to the index of refraction of a plastic sample that was the focus of the initial portion of this task; the remaining questions on the assessment were generally related to the concept of the index of refraction but did not refer back to the initial sample. The final task organization followed the surrogate model. In this model, students reviewed data that was collected and analyzed by other (fictitious) students. The students completing this task were asked to review the work presented on this assessment for errors; they evaluated the conclusions and statements presented on the assessment. Students were also asked to determine if the student work was acceptable or if this investigation should be repeated. Approximately 300 students from urban, suburban and rural districts across Western New York State participated in the study. The tasks were administered during the spring semester of the 2000--2001 school year. The participating schools had at least covered the topic of refraction, both in classroom lectures and in laboratory activities. Each student completed only one form of the task---either the integrated, the independent or the surrogate form. A set of ten questions, compiled from past New York State Regents Examinations in Physics, was used as an additional measurement of student conceptual understanding. This question set was identified as the "Optics Baseline Test" (OBT). Additionally, classroom teachers ranked the academic performance of each of the students in their classroom on the outcomes of the physics course; these rankings were compared with student scores on the performance assessment tasks. The process skills incorporated within the individual questions on each task were reviewed by a panel of expert teachers. Student scores on the tasks themselves were examined using a principal component analysis. This analysis provided support for the process skill subtests organized around the general process skills of planning, performing, and reasoning. Scoring guides and inter-rater reliabilities were established for each task. The reliabilities for tasks, subtests and questions were fairly high, indicting adequate task reliability. Correlations between student performance on the individual tasks and the OBT were not significant. Teacher ranking of student achievement in individual classrooms also failed to correlate significantly with student performance on tasks. The lack of correlation could be attributed to several factors, including (among others) a wide range of student opportunities to learn from the seven schools in the sample. As has been reported in the performance assessment literature, there were no significant differences between the performance of male and female students. (Abstract shortened by UMI.)

Persistence motives in irrational decisions to complete a boring task.

PubMed

Halkjelsvik, Torleif; Rise, Jostein

2015-01-01

We explored a novel task paradigm where participants from the online work marketplace Amazon Mechanical Turk were given the choice to quit or continue an unfinished boring task for identical economic rewards. In Studies 1a and 1b, about half the participants chose to continue (corresponding to an average of 55 and 35 cents in foregone earnings). Participants' self-reported reasons for continuing involved various types of persistence motives, reflecting a desire to persist or complete per se. Studies 2, 3a, 3b, and 3c ruled out the possibility that people continued because they enjoyed the task or believed there were additional rewards for continuing. Study 4 showed that the choice to quit/continue was associated with the manner in which the choice was presented (persistence test vs. decision-making test) and individual differences in dispositional persistence motives. The present data indicate that motivational forces independent of the focal reward may affect intertemporal decisions. © 2014 by the Society for Personality and Social Psychology, Inc.

What's the Problem? Familiarity Working Memory, and Transfer in a Problem-Solving Task.

PubMed

Kole, James A; Snyder, Hannah R; Brojde, Chandra L; Friend, Angela

2015-01-01

The contributions of familiarity and working memory to transfer were examined in the Tower of Hanoi task. Participants completed 3 different versions of the task: a standard 3-disk version, a clothing exchange task that included familiar semantic content, and a tea ceremony task that included unfamiliar semantic content. The constraints on moves were equivalent across tasks, and each could be solved with the same sequence of movements. Working memory demands were manipulated by the provision of a (static or dynamic) visual representation of the problem. Performance was equivalent for the standard Tower of Hanoi and clothing exchange tasks but worse for the tea ceremony task, and it decreased with increasing working memory demands. Furthermore, the standard Tower of Hanoi task and clothing exchange tasks independently, additively, and equivalently transferred to subsequent tasks, whereas the tea ceremony task did not. The results suggest that both familiarity and working memory demands determine overall level of performance, whereas familiarity influences transfer.

Usability of a CKD Educational Website Targeted to Patients and Their Family Members

PubMed Central

Zuckerman, Marni; Fink, Wanda; Hu, Peter; Yang, Shiming; Fink, Jeffrey C.

2012-01-01

Summary Background and objectives Web-based technology is critical to the future of healthcare. As part of the Safe Kidney Care cohort study evaluating patient safety in CKD, this study determined how effectively a representative sample of patients with CKD or family members could interpret and use the Safe Kidney Care website (www.safekidneycare.org), an informational website on safety in CKD. Design, setting, participants, & measurements Between November of 2011 and January of 2012, persons with CKD or their family members underwent formal usability testing administered by a single interviewer with a second recording observer. Each participant was independently provided a list of 21 tasks to complete, with each task rated as either easily completed/noncritical error or critical error (user cannot complete the task without significant interviewer intervention). Results Twelve participants completed formal usability testing. Median completion time for all tasks was 17.5 minutes (range=10–44 minutes). In total, 10 participants had greater than or equal to one critical error. There were 55 critical errors in 252 tasks (22%), with the highest proportion of critical errors occurring when participants were asked to find information on treatments that may damage kidneys, find the website on the internet, increase font size, and scroll to the bottom of the webpage. Participants were generally satisfied with the content and usability of the website. Conclusions Web-based educational materials for patients with CKD should target a wide range of computer literacy levels and anticipate variability in competency in use of the computer and internet. PMID:22798537

A nonlinear contextually aware prompting system (N-CAPS) to assist workers with intellectual and developmental disabilities to perform factory assembly tasks: system overview and pilot testing.

PubMed

Mihailidis, A; Melonis, M; Keyfitz, R; Lanning, M; Van Vuuren, S; Bodine, C

2016-10-01

This paper presents a new cognitive assistive technology, nonlinear contextually aware prompting system (N-CAPS) that uses advanced sensing and artificial intelligence to monitor and provide assistance to workers with cognitive disabilities during a factory assembly task. The N-CAPS system was designed through the application of various computer vision and artificial intelligence algorithms that allows the system to track a user during a specific assembly task, and then provide verbal and visual prompts to the worker as needed. A pilot study was completed with the N-CAPS solution in order to investigate whether it was an appropriate intervention. Four participants completed the required assembly task five different times, using the N-CAPS system. The participants completed all of the trials that they attempted with 85.7% of the steps completed without assistance from the job coach. Of the 85.7% of steps completed independently, 32.5% of these were completed in response to prompts given by N-CAPS. Overall system accuracy was 83.3%, the overall sensitivity was 86.2% and the overall specificity was 82.4%. The results from the study were positive in that they showed that this type of technology does have merit with this population. Implications for Rehabilitation It provides a concise summary of the importance of work in the lives of people with intellectual disabilities and how technology can support this life goal. It describes the first artificially intelligent system designed to support workers with intellectually disabilities. It provides evidence that individuals with intellectual disabilities can perform a work task in response to technology.

Evaluating the Feasibility of RESCUE: An Adjunctive HAI-Based Intervention for Veterans with PTSD

DTIC Science & Technology

2017-05-01

with clinicians on study 9/14/16 – 9/16/16. c) Independent evaluators completed 1-day Clinician Administered PTSD Scale (CAPS) training 10/31/16. d...therapists Recruit, facilitate hiring, and train study independent evaluators (IEs) 0-6 100% Facilitate and coordinate training and PE certification...developed referral stream for study 6 - 8 100% Major Task 3: Conduct pre-treatment evaluations for case series Screen, obtain consent, assess, and

Young Children's Block Play and Mathematical Learning

ERIC Educational Resources Information Center

Park, Boyoung; Chae, Jeong-Lim; Boyd, Barbara Foulks

2008-01-01

This qualitative study investigated young children's mathematical engagement in play with wooden unit blocks. Two boys, ages 6 and 7, were independently observed completing the task of filling outlined regions with the various sets of blocks. Three major mathematical actions were observed: categorizing geometric shapes, composing a larger shape…

The Association between Dual-Task Gait after Concussion and Prolonged Symptom Duration.

PubMed

Howell, David R; Brilliant, Anna; Berkstresser, Brant; Wang, Francis; Fraser, Joana; Meehan, William P

2017-12-01

Quantitative gait measurements can identify persistent postconcussion impairments. However, their prognostic utility after injury to identify the likelihood of prolonged concussion symptoms remains unknown. Our objective was to examine if dual-task gait performance measures are independently associated with persistent (> 28 days) concussion symptoms among a sample of athletes. Sixty individuals diagnosed with a sport-related concussion were assessed within 10 days of their injury. Each participant completed a postconcussion symptom scale, an injury history questionnaire, and a single/dual-task gait examination. They were followed until they no longer reported symptoms, and the duration of time required for symptom resolution was calculated. A binary multivariable logistic regression model determined the independent association between dual-task gait and symptom duration (≤ 28 days vs. >28 days) while controlling for the effect of gender, age, symptom severity, injury-to-examination time, and history of concussion. Seventeen (28%) participants reported a symptom duration >28 days. The dual-task cost for average gait speed (-25.9 ± 9.5% vs. -19.8 ± 8.9%; p = 0.027) and cadence (-18.0 ± 2.9% vs. -12.0 ± 7.7%; p = 0.029) was significantly greater among participants who experienced symptoms for >28 days. After adjusting for potential confounding variables, greater dual-task average gait speed costs were independently associated with prolonged symptom duration (aOR = 0.908; 95% CI = 0.835-0.987). Examinations of dual-task gait may provide useful information during multifaceted concussion examinations. Quantitative assessments that simultaneously test multiple domains, such as dual tasks, may be clinically valuable after a concussion to identify those more likely to experience symptoms for >28 days after injury.

Friendship group identification, multidimensional self-concept, and experience of developmental tasks in adolescence.

PubMed

Tarrant, Mark; MacKenzie, Liam; Hewitt, Lisa A

2006-08-01

This study applied a social identity perspective to the study of adolescent self-concept and social development. British adolescents aged 14-15 years (N=114) completed a questionnaire which asked them to: (i) rate their degree of identification with a school-based friendship group; (ii) complete a measure of multi-dimensional self-concept; and (iii) report their experiences of a variety of personal, relational and socio-institutional (e.g., achieving economic independence) developmental tasks. Compared to low identifiers, participants who were highly identified with a friendship group reported highest levels of self-esteem; and these differences were most marked in non-academic domains of self. High identifiers also displayed higher levels of general self-esteem and reported more positive experiences of personal and relational developmental tasks. The discussion focuses on the potential benefits to understanding of social developmental processes that can be derived from a consideration of adolescents' subjective appraisals of their peer relations.

Piecing It Together: The Effect of Background Music on Children's Puzzle Assembly.

PubMed

Koolidge, Louis; Holmes, Robyn M

2018-04-01

This study explored the effects of background music on cognitive (puzzle assembly) task performance in young children. Participants were 87 primarily European-American children (38 boys, 49 girls; mean age = 4.77 years) enrolled in early childhood classes in the northeastern United States. Children were given one minute to complete a 12-piece puzzle task in one of three background music conditions: music with lyrics, music without lyrics, and no music. The music selection was "You're Welcome" from the Disney movie "Moana." Results revealed that children who heard the music without lyrics completed more puzzle pieces than children in either the music with lyrics or no music condition. Background music without distracting lyrics may be beneficial and superior to background music with lyrics for young children's cognitive performance even when they are engaged independently in a nonverbal task.

Change in hippocampal theta activity with transfer from simple discrimination tasks to a simultaneous feature-negative task

PubMed Central

Sakimoto, Yuya; Sakata, Shogo

2014-01-01

It was showed that solving a simple discrimination task (A+, B−) and a simultaneous feature-negative (FN) task (A+, AB−) used the hippocampal-independent strategy. Recently, we showed that the number of sessions required for a rat to completely learn a task differed between the FN and simple discrimination tasks, and there was a difference in hippocampal theta activity between these tasks. These results suggested that solving the FN task relied on a different strategy than the simple discrimination task. In this study, we provided supportive evidence that solving the FN and simple discrimination tasks involved different strategies by examining changes in performance and hippocampal theta activity in the FN task after transfer from the simple discrimination task (A+, B− → A+, AB−). The results of this study showed that performance on the FN task was impaired and there was a difference in hippocampal theta activity between the simple discrimination task and FN task. Thus, we concluded that solving the FN task uses a different strategy than the simple discrimination task. PMID:24917797

Does children's moral compass waver under social pressure? Using the conformity paradigm to test preschoolers' moral and social-conventional judgments.

PubMed

Kim, Elizabeth B; Chen, Chuansheng; Smetana, Judith G; Greenberger, Ellen

2016-10-01

The current study tested whether preschoolers' moral and social-conventional judgments change under social pressure using Asch's conformity paradigm. A sample of 132 preschoolers (Mage=3.83years, SD=0.85) rated the acceptability of moral and social-conventional events and also completed a visual judgment task (i.e., comparing line length) both independently and after having viewed two peers who consistently made immoral, unconventional, or visually inaccurate judgments. Results showed evidence of conformity on all three tasks, but conformity was stronger on the social-conventional task than on the moral and visual tasks. Older children were less susceptible to pressure for social conformity for the moral and visual tasks but not for the conventional task. Copyright © 2016 Elsevier Inc. All rights reserved.

After-effects of human-computer interaction indicated by P300 of the event-related brain potential.

PubMed

Trimmel, M; Huber, R

1998-05-01

After-effects of human-computer interaction (HCI) were investigated by using the P300 component of the event-related brain potential (ERP). Forty-nine subjects (naive non-users, beginners, experienced users, programmers) completed three paper/pencil tasks (text editing, solving intelligence test items, filling out a questionnaire on sensation seeking) and three HCI tasks (text editing, executing a tutor program or programming, playing Tetris). The sequence of 7-min tasks was randomized between subjects and balanced between groups. After each experimental condition ERPs were recorded during an acoustic discrimination task at F3, F4, Cz, P3 and P4. Data indicate that: (1) mental after-effects of HCI can be detected by P300 of the ERP; (2) HCI showed in general a reduced amplitude; (3) P300 amplitude varied also with type of task, mainly at F4 where it was smaller after cognitive tasks (intelligence test/programming) and larger after emotion-based tasks (sensation seeking/Tetris); (4) cognitive tasks showed shorter latencies; (5) latencies were widely location-independent (within the range of 356-358 ms at F3, F4, P3 and P4) after executing the tutor program or programming; and (6) all observed after-effects were independent of the user's experience in operating computers and may therefore reflect short-term after-effects only and no structural changes of information processing caused by HCI.

OLDER ADULTS’ PREFERENCES FOR AND ACCEPTANCE OF ROBOT ASSISTANCE FOR EVERYDAY LIVING TASKS

PubMed Central

Smarr, Cory-Ann; Prakash, Akanksha; Beer, Jenay M.; Mitzner, Tracy L.; Kemp, Charles C.; Rogers, Wendy A.

2014-01-01

Many older adults value their independence and prefer to age in place. Robots can be designed to assist older people with performing everyday living tasks and maintaining their independence at home. Yet, there is a scarcity of knowledge regarding older adults’ attitudes toward robots and their preferences for robot assistance. Twenty-one older adults (M = 80.25 years old, SD = 7.19) completed questionnaires and participated in structured group interviews investigating their openness to and preferences for assistance from a mobile manipulator robot. Although the older adults were generally open to robot assistance for performing home-based tasks, they were selective in their views. Older adults preferred robot assistance over human assistance for many instrumental (e.g., housekeeping, laundry, medication reminders) and enhanced activities of daily living (e.g., new learning, hobbies). However, older adults were less open to robot assistance for some activities of daily living (e.g., shaving, hair care). Results from this study provide insight into older adults’ attitudes toward robot assistance with home-based everyday living tasks. PMID:25284971

Prompting Technology and Persons With Dementia: The Significance of Context and Communication.

PubMed

Braley, Rachel; Fritz, Rochelle; Van Son, Catherine R; Schmitter-Edgecombe, Maureen

2018-06-12

Smart home auto-prompting has the potential to increase the functional independence of persons with dementia (PWDs) and decrease caregiver burden as instrumental activities of daily living (IADLs) are completed at home. To improve prompting technologies, we sought to inductively understand how PWDs responded to auto-prompting while performing IADL tasks. Fifteen PWDs completed eight IADLs in a smart home testbed and received a hierarchy of verbal auto-prompts (indirect, direct, multimodal) as needed for task completion. Two researchers viewed archived videos and recorded the observed behaviors of the PWDs and their reflections watching the PWDs. Using qualitative descriptive methods, an interdisciplinary analytic team reviewed transcripts and organized data into themes using content analysis. Context and Communication emerged as the major themes, suggesting that positive user experiences will require auto-prompting systems to account for a multitude of contextual factors (individual and environmental) such as level of cognitive impairment, previous exposure to task, and familiarity of environment. Communicating with another human rather than an automated prompting system may be important if individuals begin to exhibit signs of stress while completing activities. Additional work is needed to create auto-prompting systems that provide specific, personalized, and flexible prompts. Holistic conceptualization of "successful task completion" is needed and a positive end-user experience will be key to utility. Such systems will benefit from including positive reinforcement, training, and exploration of how, and whether, direct human involvement can be minimized during the provision of in-home care.

An Exploratory Investigation on the Use of Closed-Loop Electrical Stimulation to Assist Individuals with Stroke to Perform Fine Movements with Their Hemiparetic Arm.

PubMed

Lew, Brian; Alavi, Nezam; Randhawa, Bubblepreet K; Menon, Carlo

2016-01-01

Stroke is the leading cause of upper limb impairments resulting in disability. Modern rehabilitation includes training with robotic exoskeletons and functional electrical stimulation (FES). However, there is a gap in knowledge to define the detailed use of FES in stroke rehabilitation. In this paper, we explore applying closed-loop FES to the upper extremities of healthy volunteers and individuals with a hemiparetic arm resulting from stroke. We used a set of gyroscopes to monitor arm movements and used a non-linear controller, namely, the robust integral of the sign of the error (RISE), to assess the viability of controlling FES in closed loop. Further, we explored the application of closed-loop FES in improving functional tasks performed by individuals with stroke. Four healthy individuals of ages 27-32 years old and five individuals with stroke of ages 61-83 years old participated in this study. We used the Rehastim FES unit (Hasomed Ltd.) with real-time modulation of pulse width and amplitude. Both healthy and stroke individuals were tested in RISE-controlled single and multi-joint upper limb motions following first a sinusoidal trajectory. Individuals with stroke were also asked to perform the following functional tasks: picking up a basket, picking and placing an object on a table, cutting a pizza, pulling back a chair, eating with a spoon, as well as using a stapler and grasping a pen. Healthy individuals were instructed to keep their arm relaxed during the experiment. Most individuals with stroke were able to follow the sinusoid trajectories with their arm joints under the sole excitation of the closed-loop-controlled FES. One individual with stroke, who was unable to perform any of the functional tasks independently, succeeded in completing all the tasks when FES was used. Three other individuals with stroke, who were unable to complete a few tasks independently, completed some of them when FES was used. The remaining stroke participant was able to complete all tasks with and without FES. Our results suggest that individuals with a low Fugl-Meyer score or a higher level of disability may benefit the most with the use of closed-loop-controlled FES.

An Exploratory Investigation on the Use of Closed-Loop Electrical Stimulation to Assist Individuals with Stroke to Perform Fine Movements with Their Hemiparetic Arm

PubMed Central

Lew, Brian; Alavi, Nezam; Randhawa, Bubblepreet K.; Menon, Carlo

2016-01-01

Stroke is the leading cause of upper limb impairments resulting in disability. Modern rehabilitation includes training with robotic exoskeletons and functional electrical stimulation (FES). However, there is a gap in knowledge to define the detailed use of FES in stroke rehabilitation. In this paper, we explore applying closed-loop FES to the upper extremities of healthy volunteers and individuals with a hemiparetic arm resulting from stroke. We used a set of gyroscopes to monitor arm movements and used a non-linear controller, namely, the robust integral of the sign of the error (RISE), to assess the viability of controlling FES in closed loop. Further, we explored the application of closed-loop FES in improving functional tasks performed by individuals with stroke. Four healthy individuals of ages 27–32 years old and five individuals with stroke of ages 61–83 years old participated in this study. We used the Rehastim FES unit (Hasomed Ltd.) with real-time modulation of pulse width and amplitude. Both healthy and stroke individuals were tested in RISE-controlled single and multi-joint upper limb motions following first a sinusoidal trajectory. Individuals with stroke were also asked to perform the following functional tasks: picking up a basket, picking and placing an object on a table, cutting a pizza, pulling back a chair, eating with a spoon, as well as using a stapler and grasping a pen. Healthy individuals were instructed to keep their arm relaxed during the experiment. Most individuals with stroke were able to follow the sinusoid trajectories with their arm joints under the sole excitation of the closed-loop-controlled FES. One individual with stroke, who was unable to perform any of the functional tasks independently, succeeded in completing all the tasks when FES was used. Three other individuals with stroke, who were unable to complete a few tasks independently, completed some of them when FES was used. The remaining stroke participant was able to complete all tasks with and without FES. Our results suggest that individuals with a low Fugl–Meyer score or a higher level of disability may benefit the most with the use of closed-loop-controlled FES. PMID:27014683

The use of a questionnaire and simple exercise test in the preoperative assessment of vascular surgery patients.

PubMed

McGlade, D P; Poon, A B; Davies, M J

2001-10-01

We aimed to assess the reliability of patients as historians in terms of the self assessment of functional capacity and also examined the usefulness of a simple ward exercise tolerance test. One hundred consecutive elective vascular surgery patients were interviewed preoperatively using a modified Duke Activity Status Index (DASI) questionnaire. To test reliability in reference to an independent observer, the questionnaire concerning the patient was also applied to each patient's closest relative who was blinded to the patient's responses. Patients were then asked to walk up two flights of stairs and the time taken to complete the task or the reason for failing to complete the task was recorded. The D

ABCs or 123s? The independent contributions of literacy and numeracy skills on health task performance among older adults

PubMed Central

Smith, Samuel G.; Curtis, Laura M.; O’Conor, Rachel; Federman, Alex D.; Wolf, Michael S.

2015-01-01

Objective To investigate the relationship between literacy and numeracy and their association with health task performance. Methods Older adults (n = 304) completed commonly used measures of literacy and numeracy. Single factor literacy and numeracy scores were calculated and used to predict performance on an established set of health self-management tasks, including: (i) responding to spoken information; (ii) comprehension of print and (iii) multimedia information; and (iv) organizing and dosing medication. Total and sub-scale scores were calculated. Results Literacy and numeracy measures were highly correlated (rs = 0.68; ps < 0.001). In multivariable models adjusted for age, gender, race, education, and comorbidity, lower literacy (β = 0.44, p < 0.001) and numeracy (β = 0.44, p < 0.001) were independently associated with worse overall task performance and all sub-scales (literacy range, β = 0.23–0.45, ps < 0.001; numeracy range, β = 0.31–0.41, ps < 0.001). Multivariable analyses with both constructs entered explained more variance in overall health task performance compared with separate literacy and numeracy models (8.2% and 10% respectively, ps < 0.001). Conclusion Literacy and numeracy were highly correlated, but independent predictors of health task performance. These skill sets are complementary and both are important for health self-management. Practice implications Self-management interventions may be more effective if they consider both literacy and numeracy skills rather than focusing on one specific ability. PMID:25936579

An Alternative Option to Dedicated Braille Notetakers for People with Visual Impairments: Universal Technology for Better Access

ERIC Educational Resources Information Center

Hong, Sunggye

2012-01-01

Technology provides equal access to information and helps people with visual impairments to complete tasks more independently. Among various assistive technology options for people with visual impairments, braille notetakers have been considered the most significant because of their technological innovation. Braille notetakers allow users who are…

A Brunswikian Evolutionary Developmental Theory of Preparedness and Plasticity

ERIC Educational Resources Information Center

Figueredo, Aurelio Jose; Hammond, Kenneth R.; McKiernan, Erin C.

2006-01-01

The domain-independent and domain-dependent approach to the evolution of cognition have been taken by separate groups of researchers who have focused exclusively on either the formal properties or the distinct cognitive demands of tasks. We express the view that synthesizing the two approaches could lead to a more complete understanding, and…

Comparison of Self-Prompting of Cooking Skills via Picture-Based Cookbooks and Video Recipes

ERIC Educational Resources Information Center

Mechling, Linda C.; Stephens, Erin

2009-01-01

This investigation compared the use of static picture prompting, in a cookbook format, and video prompting to self-prompt four students with moderate intellectual disabilities to independently complete multi-step cooking tasks. An adapted alternating treatments design (AATD) with baseline, alternating treatments, and final treatment condition, was…

Introspection on Uncertainty and Judicious Help-Seeking during the Preschool Years

ERIC Educational Resources Information Center

Coughlin, Christine; Hembacher, Emily; Lyons, Kristen E.; Ghetti, Simona

2015-01-01

Little is known about the mechanisms underlying a ubiquitous behavior in preschoolers, help-seeking. We tested the hypothesis that preschoolers' awareness of their own uncertainty is associated with help-seeking. Three-, 4-, and 5-year-olds (N = 125) completed a perceptual identification task twice: once independently and once when they could…

An Examination of High School Students' Online Engagement in Mathematics Problems

ERIC Educational Resources Information Center

Lim, Woong; Son, Ji-Won; Gregson, Susan; Kim, Jihye

2018-01-01

This article examines high school students' engagement in a set of trigonometry problems. Students completed this task independently in an online environment with access to Internet search engines, online textbooks, and YouTube videos. The findings imply that students have the resourcefulness to solve procedure-based mathematics problems in an…

Age-Related Differences in Multiple Task Monitoring

PubMed Central

Todorov, Ivo; Del Missier, Fabio; Mäntylä, Timo

2014-01-01

Coordinating multiple tasks with narrow deadlines is particularly challenging for older adults because of age related decline in cognitive control functions. We tested the hypothesis that multiple task performance reflects age- and gender-related differences in executive functioning and spatial ability. Young and older adults completed a multitasking session with four monitoring tasks as well as separate tasks measuring executive functioning and spatial ability. For both age groups, men exceeded women in multitasking, measured as monitoring accuracy. Individual differences in executive functioning and spatial ability were independent predictors of young adults' monitoring accuracy, but only spatial ability was related to sex differences. For older adults, age and executive functioning, but not spatial ability, predicted multitasking performance. These results suggest that executive functions contribute to multiple task performance across the adult life span and that reliance on spatial skills for coordinating deadlines is modulated by age. PMID:25215609

Age-related differences in multiple task monitoring.

PubMed

Todorov, Ivo; Del Missier, Fabio; Mäntylä, Timo

2014-01-01

Coordinating multiple tasks with narrow deadlines is particularly challenging for older adults because of age related decline in cognitive control functions. We tested the hypothesis that multiple task performance reflects age- and gender-related differences in executive functioning and spatial ability. Young and older adults completed a multitasking session with four monitoring tasks as well as separate tasks measuring executive functioning and spatial ability. For both age groups, men exceeded women in multitasking, measured as monitoring accuracy. Individual differences in executive functioning and spatial ability were independent predictors of young adults' monitoring accuracy, but only spatial ability was related to sex differences. For older adults, age and executive functioning, but not spatial ability, predicted multitasking performance. These results suggest that executive functions contribute to multiple task performance across the adult life span and that reliance on spatial skills for coordinating deadlines is modulated by age.

Independent effects of bilingualism and socioeconomic status on language ability and executive functioning.

PubMed

Calvo, Alejandra; Bialystok, Ellen

2014-03-01

One hundred and seventy-five children who were 6-years old were assigned to one of four groups that differed in socioeconomic status (SES; working class or middle class) and language background (monolingual or bilingual). The children completed tests of nonverbal intelligence, language tests assessing receptive vocabulary and attention based on picture naming, and two tests of executive functioning. All children performed equivalently on the basic intelligence tests, but performance on the language and executive functioning tasks was influenced by both SES and bilingualism. Middle-class children outperformed working-class children on all measures, and bilingual children obtained lower scores than monolingual children on language tests but higher scores than monolingual children on the executive functioning tasks. There were no interactions with either group factors or task factors. Thus, each of SES and bilingualism contribute significantly and independently to children's development irrespective of the child's level on the other factor. Copyright © 2013 Elsevier B.V. All rights reserved.

Cognitive Deficits Underlying Error Behavior on a Naturalistic Task after Severe Traumatic Brain Injury

PubMed Central

Hendry, Kathryn; Ownsworth, Tamara; Beadle, Elizabeth; Chevignard, Mathilde P.; Fleming, Jennifer; Griffin, Janelle; Shum, David H. K.

2016-01-01

People with severe traumatic brain injury (TBI) often make errors on everyday tasks that compromise their safety and independence. Such errors potentially arise from the breakdown or failure of multiple cognitive processes. This study aimed to investigate cognitive deficits underlying error behavior on a home-based version of the Cooking Task (HBCT) following TBI. Participants included 45 adults (9 females, 36 males) with severe TBI aged 18–64 years (M = 37.91, SD = 13.43). Participants were administered the HBCT in their home kitchens, with audiovisual recordings taken to enable scoring of total errors and error subtypes (Omissions, Additions, Estimations, Substitutions, Commentary/Questions, Dangerous Behavior, Goal Achievement). Participants also completed a battery of neuropsychological tests, including the Trail Making Test, Hopkins Verbal Learning Test-Revised, Digit Span, Zoo Map test, Modified Stroop Test, and Hayling Sentence Completion Test. After controlling for cooking experience, greater Omissions and Estimation errors, lack of goal achievement, and longer completion time were significantly associated with poorer attention, memory, and executive functioning. These findings indicate that errors on naturalistic tasks arise from deficits in multiple cognitive domains. Assessment of error behavior in a real life setting provides insight into individuals' functional abilities which can guide rehabilitation planning and lifestyle support. PMID:27790099

An Attempt at Matching Waking Events Into Dream Reports by Independent Judges

PubMed Central

Wang, Jia Xi; Shen, He Yong

2018-01-01

Correlations between memories and dreaming has typically been studied by linking conscious experiences and dream reports, which has illustrated that dreaming reflects waking life events, thoughts, and emotions. As some research suggests that sleep has a function of memory consolidation, and dreams reflect this, researching this relationship further may uncover more useful insights. However, most related research has been conducted using the self-report method which asks participants to judge the relationship between their own conscious experiences and dreams. This method may cause errors when the research purpose is to make comparisons between different groups, because individual differences cannot be balanced out when the results are compared among groups. Based on a knowledge of metaphors and symbols, we developed two operationalized definitions for independent judges to match conscious experiences and dreams, the descriptive incorporation and the metaphorical incorporation, and tested their reliability for the matching purpose. Two independent judges were asked to complete a linking task for 212 paired event-dreams. Results showed almost half dreams can be matched by independent judges, and the independent-judge method could provide similar proportions for the linking task, when compared with the self-report method. PMID:29681873

Cooking breakfast after a brain injury

PubMed Central

Tanguay, Annick N.; Davidson, Patrick S. R.; Guerrero Nuñez, Karla V.; Ferland, Mark B.

2014-01-01

Acquired brain injury (ABI) often compromises the ability to carry out instrumental activities of daily living such as cooking. ABI patients' difficulties with executive functions and memory result in less independent and efficient meal preparation. Accurately assessing safety and proficiency in cooking is essential for successful community reintegration following ABI, but in vivo assessment of cooking by clinicians is time-consuming, costly, and difficult to standardize. Accordingly, we examined the usefulness of a computerized meal preparation task (the Breakfast Task; Craik and Bialystok, 2006) as an indicator of real life meal preparation skills. Twenty-two ABI patients and 22 age-matched controls completed the Breakfast Task. Patients also completed the Rehabilitation Activities of Daily Living Survey (RADLS; Salmon, 2003) and prepared actual meals that were rated by members of the clinical team. As expected, the ABI patients had significant difficulty on all aspects of the Breakfast Task (failing to have all their foods ready at the same time, over- and under-cooking foods, setting fewer places at the table, and so on) relative to controls. Surprisingly, however, patients' Breakfast Task performance was not correlated with their in vivo meal preparation. These results indicate caution when endeavoring to replace traditional evaluation methods with computerized tasks for the sake of expediency. PMID:25228863

An independent shopping experience for wheelchair users through augmented reality and RFID.

PubMed

Rashid, Zulqarnain; Pous, Rafael; Norrie, Christopher S

2017-06-23

People with physical and mobility impairments continue to struggle to attain independence in the performance of routine activities and tasks. For example, browsing in a store and interacting with products located beyond an arm's length may be impossible without the enabling intervention of a human assistant. This research article describes a study undertaken to design, develop, and evaluate potential interaction methods for motor-impaired individuals, specifically those who use wheelchairs. Our study includes a user-centered approach, and a categorization of wheelchair users based upon the severity of their disability and their individual needs. We designed and developed access solutions that utilize radio frequency identification (RFID), augmented reality (AR), and touchscreen technologies in order to help people who use wheelchairs to carry out certain tasks autonomously. In this way, they have been empowered to go shopping independently, free from reliance upon the assistance of others. A total of 18 wheelchair users participated in the completed study.

Comparison of Methods for Demonstrating Passage of Time When Using Computer-Based Video Prompting

ERIC Educational Resources Information Center

Mechling, Linda C.; Bryant, Kathryn J.; Spencer, Galen P.; Ayres, Kevin M.

2015-01-01

Two different video-based procedures for presenting the passage of time (how long a step lasts) were examined. The two procedures were presented within the framework of video prompting to promote independent multi-step task completion across four young adults with moderate intellectual disability. The two procedures demonstrating passage of the…

A Common Capacity Limitation for Response and Item Selection in Working Memory

ERIC Educational Resources Information Center

Janczyk, Markus

2017-01-01

Successful completion of any cognitive task requires selecting a particular action and the object the action is applied to. Oberauer (2009) suggested a working memory (WM) model comprising a declarative and a procedural part with analogous structures. One important assumption of this model is that both parts work independently of each other, and…

Visuospatial and Attentional Abilities Predict Driving Simulator Performance Among Older HIV-infected Adults

PubMed Central

Foley, J. M.; Gooding, A. L.; Thames, A. D.; Ettenhofer, M. L.; Kim, M. S.; Castellon, S. A.; Marcotte, T. D.; Sadek, J. R.; Heaton, R. K.; van Gorp, W. G.; Hinkin, C. H.

2013-01-01

Objectives To examine the effects of aging and neuropsychological (NP) impairment on driving simulator performance within a human immunodeficiency virus (HIV)-infected cohort. Methods Participants included 79 HIV-infected adults (n = 58 > age 50, n = 21 ≤ 40) who completed a NP battery and a personnel computer-based driving simulator task. Outcome variables included total completion time (time) and number of city blocks to complete the task (blocks). Results Compared to the younger group, the older group was less efficient in their route finding (blocks over optimum: 25.9 [20.1] vs 14.4 [16.9]; P = .02) and took longer to complete the task (time: 1297.6 [577.6] vs 804.4 [458.5] seconds; P = .001). Regression models within the older adult group indicated that visuospatial abilities (blocks: b = –0.40, P < .001; time: b = –0.40, P = .001) and attention (blocks: b = –0.49, P = .001; time: b = –0.42, P = .006) independently predicted simulator performance. The NP-impaired group performed more poorly on both time and blocks, compared to the NP normal group. Conclusions Older HIV-infected adults may be at risk of driving-related functional compromise secondary to HIV-associated neurocognitive decline. PMID:23314403

Household Everyday Functioning in the Internet Age: Online Shopping and Banking Skills Are Affected in HIV-Associated Neurocognitive Disorders.

PubMed

Woods, Steven Paul; Iudicello, Jennifer E; Morgan, Erin E; Verduzco, Marizela; Smith, Tyler V; Cushman, Clint

2017-08-01

The Internet is a fundamental tool for completing many different instrumental activities of daily living (IADL), including shopping and banking. Persons with HIV-associated Neurocognitive Disorders (HAND) are at heightened risk for IADL problems, but the extent to which HAND interferes with the performance of Internet-based household IADLs is not known. Ninety-three individuals with HIV disease, 43 of whom were diagnosed with HAND, and 42 HIV- comparison participants completed Internet-based tests of shopping and banking. Participants used mock credentials to log in to an experimenter-controlled Web site and independently performed a series of typical online shopping (e.g., purchasing household goods) and banking (e.g., transferring funds between accounts) tasks. Individuals with HAND were significantly more likely to fail the online shopping task than neurocognitively normal HIV+ and HIV- participants. HAND was also associated with poorer overall performance versus HIV+ normals on the online banking task. In the HAND group, Internet-based task scores were correlated with episodic memory, executive functions, motor skills, and numeracy. In the HIV+ sample as a whole, lower Internet-based task scores were uniquely associated with poorer performance-based functional capacity and self-reported declines in shopping and financial management in daily life, but not with global manifest functional status. Findings indicate that HAND is associated with difficulties in using the Internet to complete important household everyday functioning tasks. The development and validation of effective Internet training and compensatory strategies may help to improve the household management of persons with HAND. (JINS, 2017, 23, 605-615).

Common and specific process factors in cardiac rehabilitation: independent and interactive effects of the working alliance and self-efficacy.

PubMed

Burns, John W; Evon, Donna

2007-11-01

Therapeutic processes in cardiac rehabilitation programs are virtually unexamined. Models were tested by which changes in the working alliance between patient and staff (agreement on goals/tasks; emotional bond) may affect outcomes in conjunction with changes in patient self-efficacy to change their diets and increase exercise. Cardiac patients (n = 79) participated in a 12-week program, and completed assessments at early, mid, and late treatment. Changes in cardiac depression, physical health, perceived exertion during exercise, rate/pressure product at submaximal exercise tolerance, weight loss, return to work, total fat intake. Early-treatment changes in agreement on goals/tasks were related to changes in psychosocial factors and perceived exertion during exercise independent of effects of changes in self-efficacy. Early-treatment changes in goals/tasks and self-efficacy interacted to predict changes in cardiorespiratory fitness, weight loss, and return to work such that patients high on both goals/tasks and self-efficacy showed the most gains. Sound therapeutic relationships between patients and staff may play an important role in facilitating the achievement of a wide-range of salutary outcomes during cardiac rehabilitation. (PsycINFO Database Record (c) 2007 APA, all rights reserved).

Evaluation of 16 measures of mental workload using a simulated flight task emphasizing mediational activity

NASA Technical Reports Server (NTRS)

Wierwille, W. W.; Rahimi, M.; Casali, J. G.

1985-01-01

As aircraft and other systems become more automated, a shift is occurring in human operator participation in these systems. This shift is away from manual control and toward activities that tap the higher mental functioning of human operators. Therefore, an experiment was performed in a moving-base flight simulator to assess mediational (cognitive) workload measurement. Specifically, 16 workload estimation techniques were evaluated as to their sensitivity and intrusion in a flight task emphasizing mediational behavior. Task loading, using navigation problems presented on a display, was treated as an independent variable, and workload-measure values were treated as dependent variables. Results indicate that two mediational task measures, two rating scale measures, time estimation, and two eye behavior measures were reliably sensitive to mediational loading. The time estimation measure did, however, intrude on mediational task performance. Several of the remaining measures were completely insensitive to mediational load.

Completable scheduling: An integrated approach to planning and scheduling

NASA Technical Reports Server (NTRS)

Gervasio, Melinda T.; Dejong, Gerald F.

1992-01-01

The planning problem has traditionally been treated separately from the scheduling problem. However, as more realistic domains are tackled, it becomes evident that the problem of deciding on an ordered set of tasks to achieve a set of goals cannot be treated independently of the problem of actually allocating resources to the tasks. Doing so would result in losing the robustness and flexibility needed to deal with imperfectly modeled domains. Completable scheduling is an approach which integrates the two problems by allowing an a priori planning module to defer particular planning decisions, and consequently the associated scheduling decisions, until execution time. This allows a completable scheduling system to maximize plan flexibility by allowing runtime information to be taken into consideration when making planning and scheduling decision. Furthermore, through the criteria of achievability placed on deferred decision, a completable scheduling system is able to retain much of the goal-directedness and guarantees of achievement afforded by a priori planning. The completable scheduling approach is further enhanced by the use of contingent explanation-based learning, which enables a completable scheduling system to learn general completable plans from example and improve its performance through experience. Initial experimental results show that completable scheduling outperforms classical scheduling as well as pure reactive scheduling in a simple scheduling domain.

The Associations of Naturalistic Classic Psychedelic Use, Mystical Experience, and Creative Problem Solving.

PubMed

Sweat, Noah W; Bates, Larry W; Hendricks, Peter S

2016-01-01

Developing methods for improving creativity is of broad interest. Classic psychedelics may enhance creativity; however, the underlying mechanisms of action are unknown. This study was designed to assess whether a relationship exists between naturalistic classic psychedelic use and heightened creative problem-solving ability and if so, whether this is mediated by lifetime mystical experience. Participants (N = 68) completed a survey battery assessing lifetime mystical experience and circumstances surrounding the most memorable experience. They were then administered a functional fixedness task in which faster completion times indicate greater creative problem-solving ability. Participants reporting classic psychedelic use concurrent with mystical experience (n = 11) exhibited significantly faster times on the functional fixedness task (Cohen's d = -.87; large effect) and significantly greater lifetime mystical experience (Cohen's d = .93; large effect) than participants not reporting classic psychedelic use concurrent with mystical experience. However, lifetime mystical experience was unrelated to completion times on the functional fixedness task (standardized β = -.06), and was therefore not a significant mediator. Classic psychedelic use may increase creativity independent of its effects on mystical experience. Maximizing the likelihood of mystical experience may need not be a goal of psychedelic interventions designed to boost creativity.

Effects of a Supportive Audience on a Handgrip Squeezing Task in Adults

PubMed Central

LEITZELAR, BRIANNA N.; RAZON, SELEN; TOKAC, UMIT; DIERINGER, SHANNON; BOOK, CINDY; JUDGE, LAWRENCE W.

2016-01-01

The role of social facilitation by way of audience effect in select exercise-related variables during an isometric handgrip task was assessed using a mixed design. Fifty three moderately active participants (Mage= 21.76 ± 5.27) were recruited from the Midwestern United States. Participants were randomly assigned to one of two groups: supportive audience or control. Audience members provided positive verbal encouragement to participants in the experimental condition throughout the task performance. Participants in the control group performed the task in the absence of an audience and did not receive any verbal encouragement. Participants provided anxiety ratings pre- and post-task using the State-trait anxiety inventory for adults (STAI). Participants’ ratings of perceived exertion (RPE) and heart rate (HR) were monitored and assessed at 30-second intervals. Upon task completion, sustained effort in the form of time on task was recorded in seconds. A repeated measures analysis of variance (RM ANOVA) revealed that there was a time effect within groups of HR = ( F(2.64, 131.85) = 189.3, p <0.001) and within groups of RPE = (F(2.97, 139.42) = 2189.43 p <0.001). An independent sample T-test revealed significant differences in HR at 0, 30 and 60 seconds between the groups. An independent sample T-test revealed no significant differences in anxiety and RPE between the groups. These results partially support the notion of social facilitation and may have implications for research and practice. PMID:29399254

Task difficulty moderates the revelation effect.

PubMed

Aßfalg, André; Currie, Devon; Bernstein, Daniel M

2017-05-01

Tasks that precede a recognition probe induce a more liberal response criterion than do probes without tasks-the "revelation effect." For example, participants are more likely to claim that a stimulus is familiar directly after solving an anagram, relative to a condition without an anagram. Revelation effect hypotheses disagree whether hard preceding tasks should produce a larger revelation effect than easy preceding tasks. Although some studies have shown that hard tasks increase the revelation effect as compared to easy tasks, these studies suffered from a confound of task difficulty and task presence. Conversely, other studies have shown that the revelation effect is independent of task difficulty. In the present study, we used new task difficulty manipulations to test whether hard tasks produce larger revelation effects than easy tasks. Participants (N = 464) completed hard or easy preceding tasks, including anagrams (Exps. 1 and 2) and the typing of specific arrow key sequences (Exps. 3-6). With sample sizes typical of revelation effect experiments, the effect sizes of task difficulty on the revelation effect varied considerably across experiments. Despite this variability, a consistent data pattern emerged: Hard tasks produced larger revelation effects than easy tasks. Although the present study falsifies certain revelation effect hypotheses, the general vagueness of revelation effect hypotheses remains.

Using a Personal Digital Assistant to Increase Independent Task Completion by Students with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Mechling, Linda C.; Gast, David L.; Seid, Nicole H.

2009-01-01

In this study, a personal digital assistant (PDA) with picture, auditory, and video prompts with voice over, was evaluated as a portable self-prompting device for students with autism spectrum disorder (ASD). Using a multiple probe design across three cooking recipes and replicated with three students with ASD, the system was tested for its…

Complete integrability of geodesic motion in Sasaki-Einstein toric Yp,q spaces

NASA Astrophysics Data System (ADS)

Babalic, Elena Mirela; Visinescu, Mihai

2015-09-01

We construct explicitly the constants of motion for geodesics in the five-dimensional Sasaki-Einstein spaces Yp,q. To carry out this task, we use the knowledge of the complete set of Killing vectors and Killing-Yano tensors on these spaces. In spite of the fact that we generate a multitude of constants of motion, only five of them are functionally independent implying the complete integrability of geodesic flow on Yp,q spaces. In the particular case of the homogeneous Sasaki-Einstein manifold T1,1 the integrals of motion have simpler forms and the relations between them are described in detail.

Fatigue does not conjointly alter postural and cognitive performance when standing in a shooting position under dual-task conditions.

PubMed

Bermejo, José Luis; García-Massó, Xavier; Paillard, Thierry; Noé, Frédéric

2018-02-01

This study investigated the effects of fatigue on balance control and cognitive performance in a standing shooting position. Nineteen soldiers were asked to stand while holding a rifle (single task - ST). They also had to perform this postural task while simultaneously completing a cognitive task (dual task - DT). Both the ST and DT were performed in pre- and post-fatigue conditions. In pre-fatigue, participants achieved better balance control in the DT than in the ST, thus suggesting that the increased cognitive activity associated with the DT improves balance control by shifting the attentional focus away from a highly automatised activity. In post-fatigue, balance control was degraded in both the ST and DT, while reaction time was enhanced in the first minutes following the fatiguing exercise without affecting the accuracy of response in the cognitive task, which highlights the relative independent effects of fatigue on balance control and cognitive performance.

Peer interactions of normal and attention-deficit-disordered boys during free-play, cooperative task, and simulated classroom situations.

PubMed

Cunningham, C E; Siegel, L S

1987-06-01

Groups of 30 ADD-H boys and 90 normal boys were divided into 30 mixed dyads composed of a normal and an ADD-H boy, and 30 normal dyads composed of 2 normal boys. Dyads were videotaped interacting in 15-minute free-play, 15-minute cooperative task, and 15-minute simulated classroom settings. Mixed dyads engaged in more controlling interaction than normal dyads in both free-play and simulated classroom settings. In the simulated classroom, mixed dyads completed fewer math problems and were less compliant with the commands of peers. ADD-H children spent less simulated classroom time on task and scored lower on drawing tasks than normal peers. Older dyads proved less controlling, more compliant with peer commands, more inclined to play and work independently, less active, and more likely to remain on task during the cooperative task and simulated classroom settings. Results suggest that the ADD-H child prompts a more controlling, less cooperative pattern of responses from normal peers.

Inhibitory effects of thought substitution in the think/no-think task: evidence from independent cues.

PubMed

del Prete, Francesco; Hanczakowski, Maciej; Bajo, Maria Teresa; Mazzoni, Giuliana

2015-01-01

When people try not to think about a certain item, they can accomplish this goal by using a thought substitution strategy and think about something else. Research conducted with the think/no-think (TNT) paradigm indicates that such strategy leads subsequently to forgetting the information participants tried not to think about. The present study pursued two goals. First, it investigated the mechanism of forgetting due to thought substitution, contrasting the hypothesis by which forgetting is due to blocking caused by substitutes with the hypothesis that forgetting is due to inhibition (using an independent cue methodology). Second, a boundary condition for forgetting due to thought substitution was examined by creating conditions under which the generation of appropriate substitutes would be impaired. In two experiments, participants completed a TNT task under thought substitution instructions in which either words or pseudo-words were used as original cues and memory was assessed with original and independent cues. The results revealed forgetting in both original and independent cue tests, supporting the inhibitory account of thought substitution, but only when cues were words, and not when they were non-words, pointing to the ineffectiveness of a thought substitution strategy when original cues lack semantic content.

Measuring Social Motivation Using Signal Detection and Reward Responsiveness.

PubMed

Chevallier, Coralie; Tonge, Natasha; Safra, Lou; Kahn, David; Kohls, Gregor; Miller, Judith; Schultz, Robert T

2016-01-01

Recent trends in psychiatry have emphasized the need for a shift from categorical to dimensional approaches. Of critical importance to this transformation is the availability of tools to objectively quantify behaviors dimensionally. The present study focuses on social motivation, a dimension of behavior that is central to a range of psychiatric conditions but for which a particularly small number of assays currently exist. In Study 1 (N = 48), healthy adults completed a monetary reward task and a social reward task, followed by completion of the Chapman Physical and Social Anhedonia Scales. In Study 2 (N = 26), an independent sample was recruited to assess the robustness of Study 1's findings. The reward tasks were analyzed using signal detection theory to quantify how much reward cues bias participants' responses. In both Study 1 and Study 2, social anhedonia scores were negatively correlated with change in response bias in the social reward task but not in the monetary reward task. A median split on social anhedonia scores confirmed that participants with high social anhedonia showed less change in response bias in the social reward task compared to participants with low social anhedonia. This study confirms that social anhedonia selectively affects how much an individual changes their behavior based on the presence of socially rewarding cues and establishes a tool to quantify social reward responsiveness dimensionally.

Usability assessment of an electronic health record in a comprehensive dental clinic.

PubMed

Suebnukarn, Siriwan; Rittipakorn, Pawornwan; Thongyoi, Budsara; Boonpitak, Kwanwong; Wongsapai, Mansuang; Pakdeesan, Panu

2013-12-01

In this paper we present the development and usability of an electronic health record (EHR) system in a comprehensive dental clinic.The graphic user interface of the system was designed to consider the concept of cognitive ergonomics.The cognitive task analysis was used to evaluate the user interface of the EHR by identifying all sub-tasks and classifying them into mental or physical operators, and to predict task execution time required to perform the given task. We randomly selected 30 cases that had oral examinations for routine clinical care in a comprehensive dental clinic. The results were based on the analysis of 4 prototypical tasks performed by ten EHR users. The results showed that on average a user needed to go through 27 steps to complete all tasks for one case. To perform all 4 tasks of 30 cases, they spent about 91 min (independent of system response time) for data entry, of which 51.8 min were spent on more effortful mental operators. In conclusion, the user interface can be improved by reducing the percentage of mental effort required for the tasks.

Source credibility and idea improvement have independent effects on unconscious plagiarism errors in recall and generate-new tasks.

PubMed

Perfect, Timothy J; Field, Ian; Jones, Robert

2009-01-01

Unconscious plagiarism occurs when people try to generate new ideas or when they try to recall their own ideas from among a set generated by a group. In this study, the factors that independently influence these two forms of plagiarism error were examined. Participants initially generated solutions to real-world problems in 2 domains of knowledge in collaboration with a confederate presented as an expert in 1 domain. Subsequently, the participant generated improvements to half of the ideas from each person. Participants returned 1 day later to recall either their own ideas or their partner's ideas and to complete a generate-new task. A double dissociation was observed. Generate-new plagiarism was driven by partner expertise but not by idea improvement, whereas recall plagiarism was driven by improvement but not expertise. This improvement effect on recall plagiarism was seen for the recall-own but not the recall-partner task, suggesting that the increase in recall-own plagiarism is due to mistaken idea ownership, not source confusion.

Segment-based acoustic models for continuous speech recognition

NASA Astrophysics Data System (ADS)

Ostendorf, Mari; Rohlicek, J. R.

1993-07-01

This research aims to develop new and more accurate stochastic models for speaker-independent continuous speech recognition, by extending previous work in segment-based modeling and by introducing a new hierarchical approach to representing intra-utterance statistical dependencies. These techniques, which are more costly than traditional approaches because of the large search space associated with higher order models, are made feasible through rescoring a set of HMM-generated N-best sentence hypotheses. We expect these different modeling techniques to result in improved recognition performance over that achieved by current systems, which handle only frame-based observations and assume that these observations are independent given an underlying state sequence. In the fourth quarter of the project, we have completed the following: (1) ported our recognition system to the Wall Street Journal task, a standard task in the ARPA community; (2) developed an initial dependency-tree model of intra-utterance observation correlation; and (3) implemented baseline language model estimation software. Our initial results on the Wall Street Journal task are quite good and represent significantly improved performance over most HMM systems reporting on the Nov. 1992 5k vocabulary test set.

Increased distractibility in schizotypy: Independent of individual differences in working memory capacity?

PubMed

Marsh, John E; Vachon, François; Sörqvist, Patrik

2017-03-01

Individuals with schizophrenia typically show increased levels of distractibility. This has been attributed to impaired working memory capacity (WMC), since lower WMC is typically associated with higher distractibility, and schizophrenia is typically associated with impoverished WMC. Here, participants performed verbal and spatial serial recall tasks that were accompanied by to-be-ignored speech tokens. For the few trials wherein one speech token was replaced with a different token, impairment was produced to task scores (a deviation effect). Participants subsequently completed a schizotypy questionnaire and a WMC measure. Higher schizotypy scores were associated with lower WMC (as measured with operation span, OSPAN), but WMC and schizotypy scores explained unique variance in relation to the mean magnitude of the deviation effect. These results suggest that schizotypy is associated with heightened domain-general distractibility, but that this is independent of its relationship with WMC.

The future of intelligent assistive technologies for cognition: devices under development to support independent living and aging-with-choice.

PubMed

Boger, Jennifer; Mihailidis, Alex

2011-01-01

A person's ability to be independent is dependent on his or her overall health, mobility, and ability to complete activities of daily living. Intelligent assistive technologies (IATs) are devices that incorporate context into their decision-making process, which enables them to provide customised and dynamic assistance in an appropriate manner. IATs have tremendous potential to support people with cognitive impairments as they can be used to support many facets of well-being; from augmenting memory and decision making tasks to providing autonomous and early detection of possible changes in health. This paper presents IATs that are currently in development in the research community to support tasks that can be impacted by compromised cognition. While they are not yet ready for the general public, these devices showcase the capabilities of technologies one can expect to see in the consumer marketplace in the near future.

Examining factors involved in stress-related working memory impairments: Independent or conditional effects?

PubMed

Banks, Jonathan B; Tartar, Jaime L; Tamayo, Brittney A

2015-12-01

A large and growing body of research demonstrates the impact of psychological stress on working memory. However, the typical study approach tests the effects of a single biological or psychological factor on changes in working memory. The current study attempted to move beyond the standard single-factor assessment by examining the impact of 2 possible factors in stress-related working memory impairments. To this end, 60 participants completed a working memory task before and after either a psychological stressor writing task or a control writing task and completed measures of both cortisol and mind wandering. We also included a measure of state anxiety to examine the direct and indirect effect on working memory. We found that mind wandering mediated the relationship between state anxiety and working memory at the baseline measurement. This indirect relationship was moderated by cortisol, such that the impact of mind wandering on working memory increased as cortisol levels increased. No overall working memory impairment was observed following the stress manipulation, but increases in state anxiety and mind wandering were observed. State anxiety and mind wandering independently mediated the relationship between change in working memory and threat perception. The indirect paths resulted in opposing effects on working memory. Combined, the findings from this study suggest that cortisol enhances the impact of mind wandering on working memory, that state anxiety may not always result in stress-related working memory impairments, and that high working memory performance can protect against mind wandering. (c) 2015 APA, all rights reserved).

Social motivation in prospective memory: higher importance ratings and reported performance rates for social tasks.

PubMed

Penningroth, Suzanna L; Scott, Walter D; Freuen, Margaret

2011-03-01

Few studies have addressed social motivation in prospective memory (PM). In a pilot study and two main studies, we examined whether social PM tasks possess a motivational advantage over nonsocial PM tasks. In the pilot study and Study 1, participants listed their real-life important and less important PM tasks. Independent raters categorized the PM tasks as social or nonsocial. Results from both studies showed a higher proportion of tasks rated as social when important tasks were requested than when less important tasks were requested. In Study 1, participants also reported whether they had remembered to perform each PM task. Reported performance rates were higher for tasks rated as social than for those rated as nonsocial. Finally, in Study 2, participants rated the importance of two hypothetical PM tasks, one social and one nonsocial. The social PM task was rated higher in importance. Overall, these findings suggest that social PM tasks are viewed as more important than nonsocial PM tasks and they are more likely to be performed. We propose that consideration of the social relevance of PM will lead to a more complete and ecologically valid theoretical description of PM performance. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

Intrinsic Connectivity Provides the Baseline Framework for Variability in Motor Performance: A Multivariate Fusion Analysis of Low- and High-Frequency Resting-State Oscillations and Antisaccade Performance.

PubMed

Jamadar, Sharna D; Egan, Gary F; Calhoun, Vince D; Johnson, Beth; Fielding, Joanne

2016-07-01

Intrinsic brain activity provides the functional framework for the brain's full repertoire of behavioral responses; that is, a common mechanism underlies intrinsic and extrinsic neural activity, with extrinsic activity building upon the underlying baseline intrinsic activity. The generation of a motor movement in response to sensory stimulation is one of the most fundamental functions of the central nervous system. Since saccadic eye movements are among our most stereotyped motor responses, we hypothesized that individual variability in the ability to inhibit a prepotent saccade and make a voluntary antisaccade would be related to individual variability in intrinsic connectivity. Twenty-three individuals completed the antisaccade task and resting-state functional magnetic resonance imaging (fMRI). A multivariate analysis of covariance identified relationships between fMRI oscillations (0.01-0.2 Hz) of resting-state networks determined using high-dimensional independent component analysis and antisaccade performance (latency, error rate). Significant multivariate relationships between antisaccade latency and directional error rate were obtained in independent components across the entire brain. Some of the relationships were obtained in components that overlapped substantially with the task; however, many were obtained in components that showed little overlap with the task. The current results demonstrate that even in the absence of a task, spectral power in regions showing little overlap with task activity predicts an individual's performance on a saccade task.

The role of mental rotation and memory scanning on the performance of laparoscopic skills: a study on the effect of camera rotational angle.

PubMed

Conrad, J; Shah, A H; Divino, C M; Schluender, S; Gurland, B; Shlasko, E; Szold, A

2006-03-01

The rotational angle of the laparoscopic image relative to the true horizon has an unknown influence on performance in laparoscopic procedures. This study evaluates the effect of increasing rotational angle on surgical performance. Surgical residents (group 1) (n = 6) and attending surgeons (group 2) (n = 4) were tested on two laparoscopic skills. The tasks consisted of passing a suture through an aperture, and laparoscopic knot tying. These tasks were assessed at 15 degrees intervals between 0 degrees and 90 degrees , on three consecutive repetitions. The participant's performance was evaluated based on the time required to complete the tasks and number of errors incurred. There was an increasing deterioration in suturing performance as the degree of image rotation was increased. Participants showed a statistically significant 20-120% progressive increase in time to completion of the tasks (p = 0.004), with error rates increasing from 10% to 30% (p = 0.04) as the angle increased from 0 degrees to 90 degrees. Knot-tying performance similarly showed a decrease in performance that was evident in the less experienced surgeons (p = 0.02) but with no obvious effect on the advanced laparoscopic surgeons. When evaluated independently and as a group, both novice and experienced laparoscopic surgeons showed significant prolongation to completion of suturing tasks with increased errors as the rotational angle increased. The knot-tying task shows that experienced surgeons may be able to overcome rotational effects to some extent. This is consistent with results from cognitive neuroscience research evaluating the processing of directional information in spatial motor tasks. It appears that these tasks utilize the time-consuming processes of mental rotation and memory scanning. Optimal performance during laparoscopic procedures requires that the rotation of the camera, and thus the image, be kept to a minimum to maintain a stable horizon. New technology that corrects the rotational angle may benefit the surgeon, decrease operating time, and help to prevent adverse outcomes.

Marijuana and tobacco cigarettes: Estimating their behavioral economic relationship using purchasing tasks.

PubMed

Peters, Erica N; Rosenberry, Zachary R; Schauer, Gillian L; O'Grady, Kevin E; Johnson, Patrick S

2017-06-01

Although marijuana and tobacco are commonly coused, the nature of their relationship has not been fully elucidated. Behavioral economics has characterized the relationship between concurrently available commodities but has not been applied to marijuana and tobacco couse. U.S. adults ≥18 years who coused marijuana and tobacco cigarettes were recruited via Mechanical Turk, a crowdsourcing service by Amazon. Participants (N = 82) completed online purchasing tasks assessing hypothetical marijuana or tobacco cigarette puff consumption across a range of per-puff prices; 2 single-commodity tasks assessed these when only 1 commodity was available, and 2 cross-commodity tasks assessed these in the presence of a concurrently available fixed-price commodity. Purchasing tasks generated measures of demand elasticity, that is, sensitivity of consumption to prices. In single-commodity tasks, consumption of tobacco cigarette puffs (elasticity of demand: α = 0.0075; 95% confidence interval [0.0066, 0.0085], R² = 0.72) and of marijuana puffs (α = .0044; 95% confidence interval [0.0038, 0.0049], R² = 0.71) declined significantly with increases in price per puff. In cross-commodity tasks when both tobacco cigarette puffs and marijuana puffs were available, demand for 1 commodity was independent of price increases in the other commodity (ps > .05). Results revealed that, in this small sample, marijuana and tobacco cigarettes did not substitute for each other and did not complement each other; instead, they were independent of each other. These preliminary results can inform future studies assessing the economic relationship between tobacco and marijuana in the quickly changing policy climate in the United States. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

A novel method for quantifying arm motion similarity.

PubMed

Zhi Li; Hauser, Kris; Roldan, Jay Ryan; Milutinovic, Dejan; Rosen, Jacob

2015-08-01

This paper proposes a novel task-independent method for quantifying arm motion similarity that can be applied to any kinematic/dynamic variable of interest. Given two arm motions for the same task, not necessarily with the same completion time, it plots the time-normalized curves against one another and generates four real-valued features. To validate these features we apply them to quantify the relationship between healthy and paretic arm motions of chronic stroke patients. Studying both unimanual and bimanual arm motions of eight chronic stroke patients, we find that inter-arm coupling that tends to synchronize the motions of both arms in bimanual motions, has a stronger effect at task-relevant joints than at task-irrelevant joints. It also revealed that the paretic arm suppresses the shoulder flexion of the non-paretic arm, while the latter encourages the shoulder rotation of the former.

The relation between working memory and language comprehension in signers and speakers.

PubMed

Emmorey, Karen; Giezen, Marcel R; Petrich, Jennifer A F; Spurgeon, Erin; O'Grady Farnady, Lucinda

2017-06-01

This study investigated the relation between linguistic and spatial working memory (WM) resources and language comprehension for signed compared to spoken language. Sign languages are both linguistic and visual-spatial, and therefore provide a unique window on modality-specific versus modality-independent contributions of WM resources to language processing. Deaf users of American Sign Language (ASL), hearing monolingual English speakers, and hearing ASL-English bilinguals completed several spatial and linguistic serial recall tasks. Additionally, their comprehension of spatial and non-spatial information in ASL and spoken English narratives was assessed. Results from the linguistic serial recall tasks revealed that the often reported advantage for speakers on linguistic short-term memory tasks does not extend to complex WM tasks with a serial recall component. For English, linguistic WM predicted retention of non-spatial information, and both linguistic and spatial WM predicted retention of spatial information. For ASL, spatial WM predicted retention of spatial (but not non-spatial) information, and linguistic WM did not predict retention of either spatial or non-spatial information. Overall, our findings argue against strong assumptions of independent domain-specific subsystems for the storage and processing of linguistic and spatial information and furthermore suggest a less important role for serial encoding in signed than spoken language comprehension. Copyright © 2017 Elsevier B.V. All rights reserved.

Happiness increases verbal and spatial working memory capacity where sadness does not: Emotion, working memory and executive control.

PubMed

Storbeck, Justin; Maswood, Raeya

2016-08-01

The effects of emotion on working memory and executive control are often studied in isolation. Positive mood enhances verbal and impairs spatial working memory, whereas negative mood enhances spatial and impairs verbal working memory. Moreover, positive mood enhances executive control, whereas negative mood has little influence. We examined how emotion influences verbal and spatial working memory capacity, which requires executive control to coordinate between holding information in working memory and completing a secondary task. We predicted that positive mood would improve both verbal and spatial working memory capacity because of its influence on executive control. Positive, negative and neutral moods were induced followed by completing a verbal (Experiment 1) or spatial (Experiment 2) working memory operation span task to assess working memory capacity. Positive mood enhanced working memory capacity irrespective of the working memory domain, whereas negative mood had no influence on performance. Thus, positive mood was more successful holding information in working memory while processing task-irrelevant information, suggesting that the influence mood has on executive control supersedes the independent effects mood has on domain-specific working memory.

The influence of prototype fidelity and aesthetics of design in usability tests: effects on user behaviour, subjective evaluation and emotion.

PubMed

Sauer, Juergen; Sonderegger, Andreas

2009-07-01

An empirical study examined the impact of prototype fidelity on user behaviour, subjective user evaluation and emotion. The independent factors of prototype fidelity (paper prototype, computer prototype, fully operational appliance) and aesthetics of design (high vs. moderate) were varied in a between-subjects design. The 60 participants of the experiment were asked to complete two typical tasks of mobile phone usage: sending a text message and suppressing a phone number. Both performance data and a number of subjective measures were recorded. The results suggested that task completion time may be overestimated when a computer prototype is being used. Furthermore, users appeared to compensate for deficiencies in aesthetic design by overrating the aesthetic qualities of reduced fidelity prototypes. Finally, user emotions were more positively affected by the operation of the more attractive mobile phone than by the less appealing one.

Simulation-Based Mastery Learning with Deliberate Practice Improves Clinical Performance in Spinal Anesthesia

PubMed Central

Udani, Ankeet D.; Macario, Alex; Tanaka, Maria A.; Tanaka, Pedro P.

2014-01-01

Introduction. Properly performing a subarachnoid block (SAB) is a competency expected of anesthesiology residents. We aimed to determine if adding simulation-based deliberate practice to a base curriculum improved performance of a SAB. Methods. 21 anesthesia residents were enrolled. After baseline assessment of SAB on a task-trainer, all residents participated in a base curriculum. Residents were then randomized so that half received additional deliberate practice including repetition and expert-guided, real-time feedback. All residents were then retested for technique. SABs on all residents' next three patients were evaluated in the operating room (OR). Results. Before completing the base curriculum, the control group completed 81% of a 16-item performance checklist on the task-trainer and this increased to 91% after finishing the base curriculum (P < 0.02). The intervention group also increased the percentage of checklist tasks properly completed from 73% to 98%, which was a greater increase than observed in the control group (P < 0.03). The OR time required to perform SAB was not different between groups. Conclusions. The base curriculum significantly improved resident SAB performance. Deliberate practice training added a significant, independent, incremental benefit. The clinical impact of the deliberate practice intervention in the OR on patient care is unclear. PMID:25157263

Simulation-based mastery learning with deliberate practice improves clinical performance in spinal anesthesia.

PubMed

Udani, Ankeet D; Macario, Alex; Nandagopal, Kiruthiga; Tanaka, Maria A; Tanaka, Pedro P

2014-01-01

Introduction. Properly performing a subarachnoid block (SAB) is a competency expected of anesthesiology residents. We aimed to determine if adding simulation-based deliberate practice to a base curriculum improved performance of a SAB. Methods. 21 anesthesia residents were enrolled. After baseline assessment of SAB on a task-trainer, all residents participated in a base curriculum. Residents were then randomized so that half received additional deliberate practice including repetition and expert-guided, real-time feedback. All residents were then retested for technique. SABs on all residents' next three patients were evaluated in the operating room (OR). Results. Before completing the base curriculum, the control group completed 81% of a 16-item performance checklist on the task-trainer and this increased to 91% after finishing the base curriculum (P < 0.02). The intervention group also increased the percentage of checklist tasks properly completed from 73% to 98%, which was a greater increase than observed in the control group (P < 0.03). The OR time required to perform SAB was not different between groups. Conclusions. The base curriculum significantly improved resident SAB performance. Deliberate practice training added a significant, independent, incremental benefit. The clinical impact of the deliberate practice intervention in the OR on patient care is unclear.

Cognitive and contextual correlates of spontaneous and deliberate mind-wandering.

PubMed

Robison, Matthew K; Unsworth, Nash

2018-01-01

Individuals with greater cognitive abilities generally show reduced rates of mind-wandering when completing relatively demanding tasks (Randall, Oswald, & Beier, 2014). However, it is yet unclear whether elevated rates of mind-wandering among low-ability individuals are manifestations of deliberate, intentional episodes of mind-wandering because of task disengagement or lack of motivation, or to spontaneous, unintentional failures to maintain task-oriented attention. The present study examined this issue by measuring working memory capacity (WMC), mind-wandering during 3 relatively demanding attention control tasks, and contextual variables (e.g., motivation, alertness, perceptions of task unpleasantness). Results indicated that the relationship between WMC and mind-wandering was primarily driven by spontaneous episodes. Lack of alertness also uniquely predicted more frequent spontaneous mind-wandering independently of WMC. Deliberate mind-wandering was primarily driven by a lack of motivation. Thus, cognitive and contextual factors can have distinct relationships with spontaneous and deliberate mind-wandering. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Task-independent effects are potential confounders in longitudinal imaging studies of learning in schizophrenia.

PubMed

Korostil, Michele; Fatima, Zainab; Kovacevic, Natasha; Menon, Mahesh; McIntosh, Anthony Randal

2016-01-01

Learning impairment is a core deficit in schizophrenia that impacts on real-world functioning and yet, elucidating its underlying neural basis remains a challenge. A key issue when interpreting learning-task experiments is that task-independent changes may confound interpretation of task-related signal changes in neuroimaging studies. The nature of these task-independent changes in schizophrenia is unknown. Therefore, we examined task-independent "time effects" in a group of participants with schizophrenia contrasted with healthy participants in a longitudinal fMRI learning-experiment designed to allow for examination of non-specific effects of time. Flanking the learning portions of the experiment with a task-of-no-interest allowed us to extract task-independent BOLD changes. Task-independent effects occurred in both groups, but were more robust in the schizophrenia group. There was a significant interaction effect between group and time in a distributed activity pattern that included inferior and superior temporal regions, frontal areas (left anterior insula and superior medial gyri), and parietal areas (posterior cingulate cortices and precuneus). This pattern showed task-independent linear decrease in BOLD amplitude over the two scanning sessions for the schizophrenia group, but showed either opposite effect or no activity changes for the control group. There was a trend towards a correlation between task-independent effects and the presence of more negative symptoms in the schizophrenia group. The strong interaction between group and time suggests that both the scanning experience as a whole and the transition between task-types evokes a different response in persons with schizophrenia and may confound interpretation of learning-related longitudinal imaging experiments if not explicitly considered.

Task-independent effects are potential confounders in longitudinal imaging studies of learning in schizophrenia

PubMed Central

Korostil, Michele; Fatima, Zainab; Kovacevic, Natasha; Menon, Mahesh; McIntosh, Anthony Randal

2015-01-01

Learning impairment is a core deficit in schizophrenia that impacts on real-world functioning and yet, elucidating its underlying neural basis remains a challenge. A key issue when interpreting learning-task experiments is that task-independent changes may confound interpretation of task-related signal changes in neuroimaging studies. The nature of these task-independent changes in schizophrenia is unknown. Therefore, we examined task-independent “time effects” in a group of participants with schizophrenia contrasted with healthy participants in a longitudinal fMRI learning-experiment designed to allow for examination of non-specific effects of time. Flanking the learning portions of the experiment with a task-of-no-interest allowed us to extract task-independent BOLD changes. Task-independent effects occurred in both groups, but were more robust in the schizophrenia group. There was a significant interaction effect between group and time in a distributed activity pattern that included inferior and superior temporal regions, frontal areas (left anterior insula and superior medial gyri), and parietal areas (posterior cingulate cortices and precuneus). This pattern showed task-independent linear decrease in BOLD amplitude over the two scanning sessions for the schizophrenia group, but showed either opposite effect or no activity changes for the control group. There was a trend towards a correlation between task-independent effects and the presence of more negative symptoms in the schizophrenia group. The strong interaction between group and time suggests that both the scanning experience as a whole and the transition between task-types evokes a different response in persons with schizophrenia and may confound interpretation of learning-related longitudinal imaging experiments if not explicitly considered. PMID:26759790

Reduced dual-task gait speed is associated with visual Go/No-Go brain network activation in children and adolescents with concussion.

PubMed

Howell, David R; Meehan, William P; Barber Foss, Kim D; Reches, Amit; Weiss, Michal; Myer, Gregory D

2018-05-31

To investigate the association between dual-task gait performance and brain network activation (BNA) using an electroencephalography (EEG)-based Go/No-Go paradigm among children and adolescents with concussion. Participants with a concussion completed a visual Go/No-Go task with collection of electroencephalogram brain activity. Data were treated with BNA analysis, which involves an algorithmic approach to EEG-ERP activation quantification. Participants also completed a dual-task gait assessment. The relationship between dual-task gait speed and BNA was assessed using multiple linear regression models. Participants (n = 20, 13.9 ± 2.3 years of age, 50% female) were tested at a mean of 7.0 ± 2.5 days post-concussion and were symptomatic at the time of testing (post-concussion symptom scale = 40.4 ± 21.9). Slower dual-task average gait speed (mean = 82.2 ± 21.0 cm/s) was significantly associated with lower relative time BNA scores (mean = 39.6 ± 25.8) during the No-Go task (β = 0.599, 95% CI = 0.214, 0.985, p = 0.005, R 2  = 0.405), while controlling for the effect of age and gender. Among children and adolescents with a concussion, slower dual-task gait speed was independently associated with lower BNA relative time scores during a visual Go/No-Go task. The relationship between abnormal gait behaviour and brain activation deficits may be reflective of disruption to multiple functional abilities after concussion.

Social cognition and neurocognition as independent domains in psychosis.

PubMed

van Hooren, S; Versmissen, D; Janssen, I; Myin-Germeys, I; à Campo, J; Mengelers, R; van Os, J; Krabbendam, L

2008-08-01

Patients with psychosis display alterations in social cognition as well as in the realm of neurocognition. It is unclear, however, to what degree these cognitive domains represent two separate dimensions of liability or the pleiotropic expression of a single deficit. The purpose of the present study was to investigate (i) to what extent alterations in social cognition represent an independent area of vulnerability to psychosis, separate from neurocognitive deficits and (ii) whether social cognition is one construct or can be divided into several subcomponents. Five social cognition and three neurocognitive tasks were completed by 186 participants with different levels of vulnerability for psychosis: 44 patients with psychotic disorder; 47 subjects at familial risk; 41 subjects at psychometric risk and 54 control subjects. The social cognition tasks covered important basic subcomponents of social cognition, i.e. mentalisation (or theory of mind), data gathering bias (jumping to conclusions), source monitoring and attribution style. Neurocognitive tasks assessed speed of information processing, inhibition, cognitive shifting and strategy-driven retrieval from semantic memory. The results of factor analysis suggested that neurocognition and social cognition are two separate areas of vulnerability in psychosis. Furthermore, the social cognition measures lacked significant overlap, suggesting a multidimensional construct. Cognitive liabilities to psychosis are manifold, and include key processes underlying basic person-environment interactions in daily life, independent of cognition quantified by neuropsychological tests.

POSTURAL CONTROL ASSESSMENT IN PHYSICALLY ACTIVE AND SEDENTARY INDIVIDUALS WITH PARAPLEGIA.

PubMed

Magnani, Paola Errera; Cliquet, Alberto; de Abreu, Daniela Cristina Carvalho

2017-01-01

The aim of this study was to evaluate functional independence and trunk control during maximum-range tasks in individuals with spinal cord injuries, who were divided into sedentary (SSI, n=10) and physically active (PASI, n=10) groups . Anamnesis was conducted and level and type of injury were identified (according to the American Spinal Injury Association protocol, ASIA) and the Functional Independence Measure (FIM) questionnaire was applied. For the forward and lateral reach task, the subjects were instructed to reach as far as possible. Mean data were compared using the unpaired t test and Mann-Whitney test and differences were considered significant when p<0.05 . The PASI group performed better in self-care activities (PASI: 40.8±0.42 points, SSI: 38.0±3.58 points, p=0.01), sphincter control (PASI: 10.5±1.84 points, SSI: 8.2±3.04 points, p=0.02), transfers (PASI: 20.7±0.48 points, SSI: 16.9±4.27 points, p=0.04), and total FIM score (PASI: 104.0±2.30 points, SSI 105.1±8.56 points, p=0.01). On the maximum reach task, the PASI group had a greater average range in all directions evaluated (p<0.05) . The continuous practice of exercise increased motor function independence and trunk control in individuals with complete spinal cord injury. Level of Evidence II, Prospective Comparative Study.

Audiovisual speech perception development at varying levels of perceptual processing

PubMed Central

Lalonde, Kaylah; Holt, Rachael Frush

2016-01-01

This study used the auditory evaluation framework [Erber (1982). Auditory Training (Alexander Graham Bell Association, Washington, DC)] to characterize the influence of visual speech on audiovisual (AV) speech perception in adults and children at multiple levels of perceptual processing. Six- to eight-year-old children and adults completed auditory and AV speech perception tasks at three levels of perceptual processing (detection, discrimination, and recognition). The tasks differed in the level of perceptual processing required to complete them. Adults and children demonstrated visual speech influence at all levels of perceptual processing. Whereas children demonstrated the same visual speech influence at each level of perceptual processing, adults demonstrated greater visual speech influence on tasks requiring higher levels of perceptual processing. These results support previous research demonstrating multiple mechanisms of AV speech processing (general perceptual and speech-specific mechanisms) with independent maturational time courses. The results suggest that adults rely on both general perceptual mechanisms that apply to all levels of perceptual processing and speech-specific mechanisms that apply when making phonetic decisions and/or accessing the lexicon. Six- to eight-year-old children seem to rely only on general perceptual mechanisms across levels. As expected, developmental differences in AV benefit on this and other recognition tasks likely reflect immature speech-specific mechanisms and phonetic processing in children. PMID:27106318

Audiovisual speech perception development at varying levels of perceptual processing.

PubMed

Lalonde, Kaylah; Holt, Rachael Frush

2016-04-01

This study used the auditory evaluation framework [Erber (1982). Auditory Training (Alexander Graham Bell Association, Washington, DC)] to characterize the influence of visual speech on audiovisual (AV) speech perception in adults and children at multiple levels of perceptual processing. Six- to eight-year-old children and adults completed auditory and AV speech perception tasks at three levels of perceptual processing (detection, discrimination, and recognition). The tasks differed in the level of perceptual processing required to complete them. Adults and children demonstrated visual speech influence at all levels of perceptual processing. Whereas children demonstrated the same visual speech influence at each level of perceptual processing, adults demonstrated greater visual speech influence on tasks requiring higher levels of perceptual processing. These results support previous research demonstrating multiple mechanisms of AV speech processing (general perceptual and speech-specific mechanisms) with independent maturational time courses. The results suggest that adults rely on both general perceptual mechanisms that apply to all levels of perceptual processing and speech-specific mechanisms that apply when making phonetic decisions and/or accessing the lexicon. Six- to eight-year-old children seem to rely only on general perceptual mechanisms across levels. As expected, developmental differences in AV benefit on this and other recognition tasks likely reflect immature speech-specific mechanisms and phonetic processing in children.

Goal selection versus process control while learning to use a brain-computer interface

NASA Astrophysics Data System (ADS)

Royer, Audrey S.; Rose, Minn L.; He, Bin

2011-06-01

A brain-computer interface (BCI) can be used to accomplish a task without requiring motor output. Two major control strategies used by BCIs during task completion are process control and goal selection. In process control, the user exerts continuous control and independently executes the given task. In goal selection, the user communicates their goal to the BCI and then receives assistance executing the task. A previous study has shown that goal selection is more accurate and faster in use. An unanswered question is, which control strategy is easier to learn? This study directly compares goal selection and process control while learning to use a sensorimotor rhythm-based BCI. Twenty young healthy human subjects were randomly assigned either to a goal selection or a process control-based paradigm for eight sessions. At the end of the study, the best user from each paradigm completed two additional sessions using all paradigms randomly mixed. The results of this study were that goal selection required a shorter training period for increased speed, accuracy, and information transfer over process control. These results held for the best subjects as well as in the general subject population. The demonstrated characteristics of goal selection make it a promising option to increase the utility of BCIs intended for both disabled and able-bodied users.

Adaptation and validation of the Tower of London test of planning and problem solving in people with intellectual disabilities.

PubMed

Masson, J D; Dagnan, D; Evans, J

2010-05-01

There is a need for validated, standardised tools for the assessment of executive functions in adults with intellectual disabilities (ID). This study examines the validity of a test of planning and problem solving (Tower of London) with adults with ID. Participants completed an adapted version of the Tower of London (ToL) while day-centre staff completed adaptive function (Adaptive Behaviour Scale - Residential and Community: Second Edition, modified version) and dysexecutive function (DEX-Independent Rater) questionnaires for each participant. Correlation analyses of test and questionnaire variables were undertaken. The adapted ToL has a robust structure and shows significant associations with independent living skills, challenging behaviour and behaviours related to dysexecutive function. The adapted ToL is a valid test for use with people with ID. However, there is also a need to develop other ecologically valid tools based on everyday planning tasks undertaken by people with ID.

Experimental measurement-device-independent verification of quantum steering

NASA Astrophysics Data System (ADS)

Kocsis, Sacha; Hall, Michael J. W.; Bennet, Adam J.; Saunders, Dylan J.; Pryde, Geoff J.

2015-01-01

Bell non-locality between distant quantum systems—that is, joint correlations which violate a Bell inequality—can be verified without trusting the measurement devices used, nor those performing the measurements. This leads to unconditionally secure protocols for quantum information tasks such as cryptographic key distribution. However, complete verification of Bell non-locality requires high detection efficiencies, and is not robust to typical transmission losses over long distances. In contrast, quantum or Einstein-Podolsky-Rosen steering, a weaker form of quantum correlation, can be verified for arbitrarily low detection efficiencies and high losses. The cost is that current steering-verification protocols require complete trust in one of the measurement devices and its operator, allowing only one-sided secure key distribution. Here we present measurement-device-independent steering protocols that remove this need for trust, even when Bell non-locality is not present. We experimentally demonstrate this principle for singlet states and states that do not violate a Bell inequality.

Experimental measurement-device-independent verification of quantum steering.

PubMed

Kocsis, Sacha; Hall, Michael J W; Bennet, Adam J; Saunders, Dylan J; Pryde, Geoff J

2015-01-07

Bell non-locality between distant quantum systems--that is, joint correlations which violate a Bell inequality--can be verified without trusting the measurement devices used, nor those performing the measurements. This leads to unconditionally secure protocols for quantum information tasks such as cryptographic key distribution. However, complete verification of Bell non-locality requires high detection efficiencies, and is not robust to typical transmission losses over long distances. In contrast, quantum or Einstein-Podolsky-Rosen steering, a weaker form of quantum correlation, can be verified for arbitrarily low detection efficiencies and high losses. The cost is that current steering-verification protocols require complete trust in one of the measurement devices and its operator, allowing only one-sided secure key distribution. Here we present measurement-device-independent steering protocols that remove this need for trust, even when Bell non-locality is not present. We experimentally demonstrate this principle for singlet states and states that do not violate a Bell inequality.

Mind wandering and motor control: off-task thinking disrupts the online adjustment of behavior.

PubMed

Kam, Julia W Y; Dao, Elizabeth; Blinn, Patricia; Krigolson, Olav E; Boyd, Lara A; Handy, Todd C

2012-01-01

Mind wandering episodes have been construed as periods of "stimulus-independent" thought, where our minds are decoupled from the external sensory environment. In two experiments, we used behavioral and event-related potential (ERP) measures to determine whether mind wandering episodes can also be considered as periods of "response-independent" thought, with our minds disengaged from adjusting our behavioral outputs. In the first experiment, participants performed a motor tracking task and were occasionally prompted to report whether their attention was "on-task" or "mind wandering." We found greater tracking error in periods prior to mind wandering vs. on-task reports. To ascertain whether this finding was due to attenuation in visual perception per se vs. a disruptive effect of mind wandering on performance monitoring, we conducted a second experiment in which participants completed a time-estimation task. They were given feedback on the accuracy of their estimations while we recorded their EEG, and were also occasionally asked to report their attention state. We found that the sensitivity of behavior and the P3 ERP component to feedback signals were significantly reduced just prior to mind wandering vs. on-task attentional reports. Moreover, these effects co-occurred with decreases in the error-related negativity elicited by feedback signals (fERN), a direct measure of behavioral feedback assessment in cortex. Our findings suggest that the functional consequences of mind wandering are not limited to just the processing of incoming stimulation per se, but extend as well to the control and adjustment of behavior.

Hands-on Simulation versus Traditional Video-learning in Teaching Microsurgery Technique

PubMed Central

SAKAMOTO, Yusuke; OKAMOTO, Sho; SHIMIZU, Kenzo; ARAKI, Yoshio; HIRAKAWA, Akihiro; WAKABAYASHI, Toshihiko

2017-01-01

Bench model hands-on learning may be more effective than traditional didactic practice in some surgical fields. However, this has not been reported for microsurgery. Our study objective was to demonstrate the efficacy of bench model hands-on learning in acquiring microsuturing skills. The secondary objective was to evaluate the aptitude for microsurgery based on personality assessment. Eighty-six medical students comprising 62 men and 24 women were randomly assigned to either 20 min of hands-on learning with a bench model simulator or 20 min of video-learning using an instructional video. They then practiced microsuturing for 40 min. Each student then made three knots, and the time to complete the task was recorded. The final products were scored by two independent graders in a blind fashion. All participants then took a personality test, and their microsuture test scores and the time to complete the task were compared. The time to complete the task was significantly shorter in the simulator group than in the video-learning group. The final product scores tended to be higher with simulator-learning than with video-learning, but the difference was not significant. Students with high “extraversion” scores on the personality inventory took a shorter time to complete the suturing test. Simulator-learning was more effective for microsurgery training than video instruction, especially in understanding the procedure. There was a weak association between personality traits and microsurgery skill. PMID:28381653

A report on the USL NASA/RECON project. Part 1: The development of a transportable, university level, IS and R educational program

NASA Technical Reports Server (NTRS)

Dominick, Wayne D. (Editor); Gallagher, Suzy; Granier, Martin

1984-01-01

A project is described which has as its goal the production of a set of system-independent, discipline-independent, transportable college level courses to educate science and engineering students in the use of large-scale information storage and retrieval systems. This project is being conducted with the cooperation and sponsorship of NASA by R and D teams at the University of Southwest Louisiana and Southern University. Chapter 1 is an introduction, providing an overview and a listing of the management phases. Chapter 2 furnishes general information regarding accomplishments in areas under development. Chapter 3 deals with the development of the course materials by presenting a series of diagrams and keys to depict the progress and interrelationships of various tasks and sub-tasks. Chapter 4 presents plans for activities to be conducted to complete and deliver course materials. The final chapter is a summary of project objectives, methods, plans, and accomplishments.

Indoor Navigation by People with Visual Impairment Using a Digital Sign System

PubMed Central

Legge, Gordon E.; Beckmann, Paul J.; Tjan, Bosco S.; Havey, Gary; Kramer, Kevin; Rolkosky, David; Gage, Rachel; Chen, Muzi; Puchakayala, Sravan; Rangarajan, Aravindhan

2013-01-01

There is a need for adaptive technology to enhance indoor wayfinding by visually-impaired people. To address this need, we have developed and tested a Digital Sign System. The hardware and software consist of digitally-encoded signs widely distributed throughout a building, a handheld sign-reader based on an infrared camera, image-processing software, and a talking digital map running on a mobile device. Four groups of subjects—blind, low vision, blindfolded sighted, and normally sighted controls—were evaluated on three navigation tasks. The results demonstrate that the technology can be used reliably in retrieving information from the signs during active mobility, in finding nearby points of interest, and following routes in a building from a starting location to a destination. The visually impaired subjects accurately and independently completed the navigation tasks, but took substantially longer than normally sighted controls. This fully functional prototype system demonstrates the feasibility of technology enabling independent indoor navigation by people with visual impairment. PMID:24116156

Synchronized movement experience enhances peer cooperation in preschool children.

PubMed

Rabinowitch, Tal-Chen; Meltzoff, Andrew N

2017-08-01

Cooperating with other people is a key achievement in child development and is essential for human culture. We examined whether we could induce 4-year-old children to increase their cooperation with an unfamiliar peer by providing the peers with synchronized motion experience prior to the tasks. Children were randomly assigned to independent treatment and control groups. The treatment of synchronous motion caused children to enhance their cooperation, as measured by the speed of joint task completion, compared with control groups that underwent asynchronous motion or no motion at all. Further analysis suggested that synchronization experience increased intentional communication between peer partners, resulting in increased coordination and cooperation. Copyright © 2017 Elsevier Inc. All rights reserved.

Environment Mediated Drug Resistance in Neuroblastoma

DTIC Science & Technology

2015-12-01

activate STAT3 and MYC in neuroblastomas independently of IL6). Figure 9: Effect of IL-6 knockout crossing with NB- Tag mice. (A) MRI of abdominal...production. (D) Representative MRI images of NB-Tag and NB- Tag/IL-6KO pre-chemotherapy, post 3 and 6 weeks of chemotherapy. Task 6. Contribution of bone...described (16). Cells were lysed in radioimmunoprecipitation assay (RIPA) buffer supplemented with 1 tablet of complete mini-EDTA protease inhibitor

Marijuana Primes, Marijuana Expectancies, and Arithmetic Efficiency*

PubMed Central

Hicks, Joshua A.; Pedersen, Sarah L.; McCarthy, Denis M.; Friedman, Ronald S.

2009-01-01

Objective: Previous research has shown that primes associated with alcohol influence behavior consistent with specific alcohol expectancies. The present study examined whether exposure to marijuana-related primes and marijuana expectancies interact to produce similar effects. Specifically, the present study examined whether marijuana primes and marijuana expectancies regarding cognitive and behavioral impairment interact to influence performance on an arithmetic task. Method: Two independent samples (N = 260) of undergraduate students (both marijuana users and nonusers) first completed measures of marijuana-outcome expectancies associated with cognitive and behavioral impairment and with general negative effects (Sample 2). Later in the semester, participants were exposed to marijuana-related (or neutral) primes and then completed an arithmetic task. Results: Results from Sample 1 indicated that participants who were exposed to marijuana-themed magazine covers performed more poorly on the arithmetic task if they expected that marijuana would lead to cognitive and behavioral impairment. Results from Sample 2 indicated that, for marijuana users, cognitive and behavioral impairment expectancies, but not expectancies regarding general negative effects, similarly moderated arithmetic performance for participants exposed to marijuana-related words. Conclusions: Results support the hypothesis that the implicit activation of specific marijuana-outcome expectancies can influence cognitive processes. Implications for research on marijuana are discussed. PMID:19371490

POSTURAL CONTROL ASSESSMENT IN PHYSICALLY ACTIVE AND SEDENTARY INDIVIDUALS WITH PARAPLEGIA

PubMed Central

Magnani, Paola Errera; Cliquet, Alberto; de Abreu, Daniela Cristina Carvalho

2017-01-01

ABSTRACT Objective: The aim of this study was to evaluate functional independence and trunk control during maximum-range tasks in individuals with spinal cord injuries, who were divided into sedentary (SSI, n=10) and physically active (PASI, n=10) groups . Methods: Anamnesis was conducted and level and type of injury were identified (according to the American Spinal Injury Association protocol, ASIA) and the Functional Independence Measure (FIM) questionnaire was applied. For the forward and lateral reach task, the subjects were instructed to reach as far as possible. Mean data were compared using the unpaired t test and Mann-Whitney test and differences were considered significant when p<0.05 . Results: The PASI group performed better in self-care activities (PASI: 40.8±0.42 points, SSI: 38.0±3.58 points, p=0.01), sphincter control (PASI: 10.5±1.84 points, SSI: 8.2±3.04 points, p=0.02), transfers (PASI: 20.7±0.48 points, SSI: 16.9±4.27 points, p=0.04), and total FIM score (PASI: 104.0±2.30 points, SSI 105.1±8.56 points, p=0.01). On the maximum reach task, the PASI group had a greater average range in all directions evaluated (p<0.05) . Conclusion: The continuous practice of exercise increased motor function independence and trunk control in individuals with complete spinal cord injury. Level of Evidence II, Prospective Comparative Study. PMID:28955171

Dissociating intuitive physics from intuitive psychology: Evidence from Williams syndrome.

PubMed

Kamps, Frederik S; Julian, Joshua B; Battaglia, Peter; Landau, Barbara; Kanwisher, Nancy; Dilks, Daniel D

2017-11-01

Prior work suggests that our understanding of how things work ("intuitive physics") and how people work ("intuitive psychology") are distinct domains of human cognition. Here we directly test the dissociability of these two domains by investigating knowledge of intuitive physics and intuitive psychology in adults with Williams syndrome (WS) - a genetic developmental disorder characterized by severely impaired spatial cognition, but relatively spared social cognition. WS adults and mental-age matched (MA) controls completed an intuitive physics task and an intuitive psychology task. If intuitive physics is a distinct domain (from intuitive psychology), then we should observe differential impairment on the physics task for individuals with WS compared to MA controls. Indeed, adults with WS performed significantly worse on the intuitive physics than the intuitive psychology task, relative to controls. These results support the hypothesis that knowledge of the physical world can be disrupted independently from knowledge of the social world. Copyright © 2017 Elsevier B.V. All rights reserved.

Object-based and egocentric mental rotation performance in older adults: the importance of gender differences and motor ability.

PubMed

Jansen, Petra; Kaltner, Sandra

2014-01-01

In this study, mental rotation performance was assessed in both an object-based task, human figures and letters as stimuli, and in an egocentric-based task, a human figure as a stimulus, in 60 older persons between 60 and 71 years old (30 women, 30 men). Additionally all participants completed three motor tests measuring balance and mobility. The results show that the reaction time was slower for letters than for both human figure tasks and the mental rotation speed was faster over all for egocentric mental rotation tasks. Gender differences were found in the accuracy measurement, favoring males, and were independent of stimulus type, kind of transformation, and angular disparity. Furthermore, a regression analysis showed that the accuracy rate for object-based transformations with body stimuli could be predicted by gender and balance ability. This study showed that the mental rotation performance in older adults depends on stimulus type, kind of transformation, and gender and that performance partially relates to motor ability.

Theory of Mind in Schizophrenia: Associations With Clinical and Cognitive Insight Controlling for Levels of Psychopathology.

PubMed

Popolo, Raffaele; Dimaggio, Giancarlo; Luther, Lauren; Vinci, Giancarlo; Salvatore, Giampaolo; Lysaker, Paul H

2016-03-01

Poor insight in schizophrenia is a risk factor for both poor outcomes and treatment adherence. Accordingly, interest in identifying causes of poor insight has increased. This study explored whether theory of mind (ToM) impairments are linked to poor clinical and cognitive insight independent of psychopathology. Participants with schizophrenia (n = 37) and control subjects (n = 40) completed assessments of ToM with the Hinting Task and the Brüne Picture Sequencing Task, clinical insight and psychopathology with the Positive and Negative Syndrome Scale, and cognitive insight with the Beck Cognitive Insight Scale. Results indicated that the schizophrenia group had greater impairments in ToM relative to control subjects. In the schizophrenia group, the Hinting Task performance was related to both cognitive and clinical insight, with only the relationship with cognitive insight persisting after controlling for psychopathology. Picture Sequencing Task performance was related to cognitive insight only. Future research directions and clinical implications are discussed.

The contribution of temporary storage and executive processes to category learning.

PubMed

Wang, Tengfei; Ren, Xuezhu; Schweizer, Karl

2015-09-01

Three distinctly different working memory processes, temporary storage, mental shifting and inhibition, were proposed to account for individual differences in category learning. A sample of 213 participants completed a classic category learning task and two working memory tasks that were experimentally manipulated for tapping specific working memory processes. Fixed-links models were used to decompose data of the category learning task into two independent components representing basic performance and improvement in performance in category learning. Processes of working memory were also represented by fixed-links models. In a next step the three working memory processes were linked to components of category learning. Results from modeling analyses indicated that temporary storage had a significant effect on basic performance and shifting had a moderate effect on improvement in performance. In contrast, inhibition showed no effect on any component of the category learning task. These results suggest that temporary storage and the shifting process play different roles in the course of acquiring new categories. Copyright © 2015 Elsevier B.V. All rights reserved.

Gender differences in multitasking reflect spatial ability.

PubMed

Mäntylä, Timo

2013-04-01

Demands involving the scheduling and interleaving of multiple activities have become increasingly prevalent, especially for women in both their paid and unpaid work hours. Despite the ubiquity of everyday requirements to multitask, individual and gender-related differences in multitasking have gained minimal attention in past research. In two experiments, participants completed a multitasking session with four gender-fair monitoring tasks and separate tasks measuring executive functioning (working memory updating) and spatial ability (mental rotation). In both experiments, males outperformed females in monitoring accuracy. Individual differences in executive functioning and spatial ability were independent predictors of monitoring accuracy, but only spatial ability mediated gender differences in multitasking. Menstrual changes accentuated these effects, such that gender differences in multitasking (and spatial ability) were eliminated between males and females who were in the menstrual phase of the menstrual cycle but not between males and females who were in the luteal phase. These findings suggest that multitasking involves spatiotemporal task coordination and that gender differences in multiple-task performance reflect differences in spatial ability.

The modality effect of ego depletion: Auditory task modality reduces ego depletion.

PubMed

Li, Qiong; Wang, Zhenhong

2016-08-01

An initial act of self-control that impairs subsequent acts of self-control is called ego depletion. The ego depletion phenomenon has been observed consistently. The modality effect refers to the effect of the presentation modality on the processing of stimuli. The modality effect was also robustly found in a large body of research. However, no study to date has examined the modality effects of ego depletion. This issue was addressed in the current study. In Experiment 1, after all participants completed a handgrip task, one group's participants completed a visual attention regulation task and the other group's participants completed an auditory attention regulation task, and then all participants again completed a handgrip task. The ego depletion phenomenon was observed in both the visual and the auditory attention regulation task. Moreover, participants who completed the visual task performed worse on the handgrip task than participants who completed the auditory task, which indicated that there was high ego depletion in the visual task condition. In Experiment 2, participants completed an initial task that either did or did not deplete self-control resources, and then they completed a second visual or auditory attention control task. The results indicated that depleted participants performed better on the auditory attention control task than the visual attention control task. These findings suggest that altering task modality may reduce ego depletion. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Toward a reliable gaze-independent hybrid BCI combining visual and natural auditory stimuli.

PubMed

Barbosa, Sara; Pires, Gabriel; Nunes, Urbano

2016-03-01

Brain computer interfaces (BCIs) are one of the last communication options for patients in the locked-in state (LIS). For complete LIS patients, interfaces must be gaze-independent due to their eye impairment. However, unimodal gaze-independent approaches typically present levels of performance substantially lower than gaze-dependent approaches. The combination of multimodal stimuli has been pointed as a viable way to increase users' performance. A hybrid visual and auditory (HVA) P300-based BCI combining simultaneously visual and auditory stimulation is proposed. Auditory stimuli are based on natural meaningful spoken words, increasing stimuli discrimination and decreasing user's mental effort in associating stimuli to the symbols. The visual part of the interface is covertly controlled ensuring gaze-independency. Four conditions were experimentally tested by 10 healthy participants: visual overt (VO), visual covert (VC), auditory (AU) and covert HVA. Average online accuracy for the hybrid approach was 85.3%, which is more than 32% over VC and AU approaches. Questionnaires' results indicate that the HVA approach was the less demanding gaze-independent interface. Interestingly, the P300 grand average for HVA approach coincides with an almost perfect sum of P300 evoked separately by VC and AU tasks. The proposed HVA-BCI is the first solution simultaneously embedding natural spoken words and visual words to provide a communication lexicon. Online accuracy and task demand of the approach compare favorably with state-of-the-art. The proposed approach shows that the simultaneous combination of visual covert control and auditory modalities can effectively improve the performance of gaze-independent BCIs. Copyright © 2015 Elsevier B.V. All rights reserved.

Usability testing of an mHealth device for swallowing therapy in head and neck cancer survivors.

PubMed

Constantinescu, Gabriela; Kuffel, Kristina; King, Ben; Hodgetts, William; Rieger, Jana

2018-04-01

The objective of this study was to conduct the first patient usability testing of a mobile health (mHealth) system for in-home swallowing therapy. Five participants with a history of head and neck cancer evaluated the mHealth system. After completing an in-application (app) tutorial with the clinician, participants were asked to independently complete five tasks: pair the device to the smartphone, place the device correctly, exercise, interpret progress displays, and close the system. Quantitative and qualitative methods were used to evaluate the effectiveness, efficiency, and satisfaction with the system. Critical changes to the app were found in three of the tasks, resulting in recommendations for the next iteration. These issues were related to ease of Bluetooth pairing, placement of device, and interpretation of statistics. Usability testing with patients identified issues that were essential to address prior to implementing the mHealth system in subsequent clinical trials. Of the usability methods used, video observation (synced screen capture with videoed gestures) revealed the most information.

The importance of source and cue type in time-based everyday prospective memory.

PubMed

Oates, Joyce M; Peynircioğlu, Zehra F

2014-01-01

We examined the effects of the source of a prospective memory task (provided or generated) and the type of cue (specific or general) triggering that task in everyday settings. Participants were asked to complete both generated and experimenter-provided tasks and to send a text message when each task was completed. The cue/context for the to-be-completed tasks was either a specific time or a general deadline (time-based cue), and the cue/context for the texting task was the completion of the task itself (activity-based cue). Although generated tasks were completed more often, generated cues/contexts were no more effective than provided ones in triggering the intention. Furthermore, generated tasks were completed more often when the cue/context comprised a specific time, whereas provided tasks were completed more often when the cue/context comprised a general deadline. However, texting was unaffected by the source of the cue/context. Finally, emotion modulated the effects. Results are discussed within a process-driven framework.

Dynamics of Cooperation in a Task Completion Social Dilemma

PubMed Central

Passino, Kevin M.

2017-01-01

We study the situation where the members of a community have the choice to participate in the completion of a common task. The process of completing the task involves only costs and no benefits to the individuals that participate in this process. However, completing the task results in changes that significantly benefit the community and that exceed the participation efforts. A task completion social dilemma arises when the short-term participation costs dissipate any interest in the community members to contribute to the task completion process and therefore to obtain the benefits that result from completing the task. In this work, we model the task completion problem using a dynamical system that characterizes the participation dynamics in the community and the task completion process. We show how this model naturally allows for the incorporation of several mechanisms that facilitate the emergence of cooperation and that have been studied in previous research on social dilemmas, including communication across a network, and indirect reciprocity through relative reputation. We provide mathematical analyses and computer simulations to study the qualitative properties of the participation dynamics in the community for different scenarios. PMID:28125721

Alternating between pro- and antisaccades: switch-costs manifest via decoupling the spatial relations between stimulus and response.

PubMed

Heath, Matthew; Gillen, Caitlin; Samani, Ashna

2016-03-01

Antisaccades are a nonstandard task requiring a response mirror-symmetrical to the location of a target. The completion of an antisaccade has been shown to delay the reaction time (RT) of a subsequent prosaccade, whereas the converse switch elicits a null RT cost (i.e., the unidirectional prosaccade switch-cost). The present study sought to determine whether the prosaccade switch-cost arises from low-level interference specific to the sensory features of a target (i.e., modality-dependent) or manifests via the high-level demands of dissociating the spatial relations between stimulus and response (i.e., modality-independent). Participants alternated between pro- and antisaccades wherein the target associated with the response alternated between visual and auditory modalities. Thus, the present design involved task-switch (i.e., switching from a pro- to antisaccade and vice versa) and modality-switch (i.e., switching from a visual to auditory target and vice versa) trials as well as their task- and modality-repetition counterparts. RTs were longer for modality-switch than modality-repetition trials. Notably, however, modality-switch trials did not nullify or lessen the unidirectional prosaccade switch-cost; that is, the magnitude of the RT cost for task-switch prosaccades was equivalent across modality-switch and modality-repetition trials. Thus, competitive interference within a sensory modality does not contribute to the unidirectional prosaccade switch-cost. Instead, the modality-independent findings evince that dissociating the spatial relations between stimulus and response instantiates a high-level and inertially persistent nonstandard task-set that impedes the planning of a subsequent prosaccade.

Parent-Adolescent Discrepancies in Adolescents’ Competence and the Balance of Adolescent Autonomy and Adolescent and Parent Well-Being in the Context of Type 1 Diabetes

PubMed Central

Butner, Jonathan; Berg, Cynthia A.; Osborn, Peter; Butler, Jorie M.; Godri, Carine; Fortenberry, Katie T.; Barach, Ilana; Le, Hai; Wiebe, Deborah J.

2009-01-01

We examined whether intra-family discrepancies in perceptions of the adolescent’s competence and independence were associated with autonomy and also well-being for adolescents and parents. The latent discrepancy model was used to examine the ways that mothers and fathers consistently differed from their adolescent across measures of independence and competence regarding type 1 diabetes, a stressful context for families. One-hundred and eighty-five mothers, fathers, and adolescents (M age= 12.5 SD= 1.3) completed measures of the adolescent’s independence in completing diabetes tasks, problems with diabetes management, adherence to the medical regimen, measures of well-being, and metabolic control. The latent discrepancy model was conducted via structural equation modeling that generated latent discrepancies from the adolescent for mothers and fathers. Both mothers and fathers viewed the adolescent’s competence more negatively than did the adolescent. These discrepancies related to more parental encouragement of independence and adolescent autonomy, but also poorer metabolic control, and poorer parental psychosocial well-being. The results are interpreted within a developmental perspective that views discrepancies as reflecting normative developmental processes of autonomy, but associated with disruptions in well-being in the short term. PMID:19413435

Parent-adolescent discrepancies in adolescents' competence and the balance of adolescent autonomy and adolescent and parent well-being in the context of Type 1 diabetes.

PubMed

Butner, Jonathan; Berg, Cynthia A; Osborn, Peter; Butler, Jorie M; Godri, Carine; Fortenberry, Katie T; Barach, Ilana; Le, Hai; Wiebe, Deborah J

2009-05-01

This study examined whether intrafamily discrepancies in perceptions of the adolescent's competence and independence were associated with autonomy and well-being for adolescents and parents. The ways in which mothers and fathers consistently differed from their adolescent across measures of independence and competence regarding Type 1 diabetes, a stressful context for families, were examined with the latent discrepancy model. A sample of 185 adolescents (mean age = 12.5 years, SD = 1.3), their mothers, and participating fathers completed measures of the adolescent's independence in completing diabetes tasks, problems with diabetes management, adherence to the medical regimen, measures of well-being, and metabolic control. The latent discrepancy model was conducted via structural equation modeling that generated latent discrepancies from the adolescent for mothers and fathers. Both mothers and fathers viewed the adolescent's competence more negatively than did the adolescent. These discrepancies related to more parental encouragement of independence and adolescent autonomy but also to poorer metabolic control and poorer parental psychosocial well-being. The results are interpreted within a developmental perspective that views discrepancies as reflecting normative developmental processes of autonomy but as being associated with disruptions in well-being in the short term. Copyright 2009 APA, all rights reserved

The relationship between executive function and fine motor control in young and older adults.

PubMed

Corti, Emily J; Johnson, Andrew R; Riddle, Hayley; Gasson, Natalie; Kane, Robert; Loftus, Andrea M

2017-01-01

The present study examined the relationship between executive function (EF) and fine motor control in young and older healthy adults. Participants completed 3 measures of executive function; a spatial working memory (SWM) task, the Stockings of Cambridge task (planning), and the Intra-Dimensional Extra-Dimensional Set-Shift task (set-shifting). Fine motor control was assessed using 3 subtests of the Purdue Pegboard (unimanual, bimanual, sequencing). For the younger adults, there were no significant correlations between measures of EF and fine motor control. For the older adults, all EFs significantly correlated with all measures of fine motor control. Three separate regressions examined whether planning, SWM and set-shifting independently predicted unimanual, bimanual, and sequencing scores for the older adults. Planning was the primary predictor of performance on all three Purdue subtests. A multiple-groups mediation model examined whether planning predicted fine motor control scores independent of participants' age, suggesting that preservation of planning ability may support fine motor control in older adults. Planning remained a significant predictor of unimanual performance in the older age group, but not bimanual or sequencing performance. The findings are discussed in terms of compensation theory, whereby planning is a key compensatory resource for fine motor control in older adults. Copyright © 2016 Elsevier B.V. All rights reserved.

Theory of mind through the ages: older and middle-aged adults exhibit more errors than do younger adults on a continuous false belief task.

PubMed

Bernstein, Daniel M; Thornton, Wendy Loken; Sommerville, Jessica A

2011-10-01

Theory of mind (ToM), or the ability to understand mental states, is a fundamental aspect of social cognition. Previous research has documented marked advances in ToM in preschoolers, and declines in ToM in older-aged adults. In the present study, younger (n=37), middle-aged (n=20), and older (n=37) adults completed a continuous false belief task measuring ToM. Middle-aged and older adults exhibited more false belief bias than did younger adults, irrespective of language ability, executive function, processing speed, and memory. The authors conclude that ToM declines from younger to older adulthood, independent of age-related changes to domain-general cognitive functioning.

Usability of a Low-Cost Head Tracking Computer Access Method following Stroke.

PubMed

Mah, Jasmine; Jutai, Jeffrey W; Finestone, Hillel; Mckee, Hilary; Carter, Melanie

2015-01-01

Assistive technology devices for computer access can facilitate social reintegration and promote independence for people who have had a stroke. This work describes the exploration of the usefulness and acceptability of a new computer access device called the Nouse™ (Nose-as-mouse). The device uses standard webcam and video recognition algorithms to map the movement of the user's nose to a computer cursor, thereby allowing hands-free computer operation. Ten participants receiving in- or outpatient stroke rehabilitation completed a series of standardized and everyday computer tasks using the Nouse™ and then completed a device usability questionnaire. Task completion rates were high (90%) for computer activities only in the absence of time constraints. Most of the participants were satisfied with ease of use (70%) and liked using the Nouse™ (60%), indicating they could resume most of their usual computer activities apart from word-processing using the device. The findings suggest that hands-free computer access devices like the Nouse™ may be an option for people who experience upper motor impairment caused by stroke and are highly motivated to resume personal computing. More research is necessary to further evaluate the effectiveness of this technology, especially in relation to other computer access assistive technology devices.

The hemodynamic changes in the human prefrontal cortex during the Flanker and Simon tasks: a fNIRS study

NASA Astrophysics Data System (ADS)

Yuan, Zhen; Lin, Xiaohong

2016-03-01

Functional near-infrared spectroscopy (fNIRS) is a low-cost, portable and noninvasive functional neuroimaging technique by measuring the change in the concentrations of oxyhemoglobin (HbO) and deoxyhemoglobin (HbR). The aim of present study is to reveal the different brain activity pattern of adult subjects during the completion of flanker and Simon tasks underlying the congruent and incongruent test conditions so as to identify the basic neural mechanism of inhibitory control in executive function. In the study, we utilized fNIRS to explore the hemodynamic changes in the prefrontal cortex and our imaging results suggested that there were notable differences for the hemodynamic responses between the flank and Simon task. A striking difference is that for the flank task, the increase in the HbO concentration during incongruent trials was larger than that during congruent trials for the channels across middle frontal cortex while for the Simon task, the hemodynamic response was stronger for the congruent condition compared to that from the incongruent one. Interestingly, the hemodynamic response exhibited similar task-related activation in the superior frontal cortex for both the congruent and incongruent conditions. Further, independent component analysis showed that different brain activation patterns were identified to accomplish different inhibitory control tasks underlying the congruent and incongruent conditions.

Amygdala task-evoked activity and task-free connectivity independently contribute to feelings of arousal.

PubMed

Touroutoglou, Alexandra; Bickart, Kevin C; Barrett, Lisa Feldman; Dickerson, Bradford C

2014-10-01

Individual differences in the intensity of feelings of arousal while viewing emotional pictures have been associated with the magnitude of task-evoked blood-oxygen dependent (BOLD) response in the amygdala. Recently, we reported that individual differences in feelings of arousal are associated with task-free (resting state) connectivity within the salience network. There has not yet been an investigation of whether these two types of functional magnetic resonance imaging (MRI) measures are redundant or independent in their relationships to behavior. Here we tested the hypothesis that a combination of task-evoked amygdala activation and task-free amygdala connectivity within the salience network relate to individual differences in feelings of arousal while viewing of negatively potent images. In 25 young adults, results revealed that greater task-evoked amygdala activation and stronger task-free amygdala connectivity within the salience network each contributed independently to feelings of arousal, predicting a total of 45% of its variance. Individuals who had both increased task-evoked amygdala activation and stronger task-free amygdala connectivity within the salience network had the most heightened levels of arousal. Task-evoked amygdala activation and task-free amygdala connectivity within the salience network were not related to each other, suggesting that resting-state and task-evoked dynamic brain imaging measures may provide independent and complementary information about affective experience, and likely other kinds of behaviors as well. Copyright © 2014 Wiley Periodicals, Inc.

Task Selection, Task Switching and Multitasking during Computer-Based Independent Study

ERIC Educational Resources Information Center

Judd, Terry

2015-01-01

Detailed logs of students' computer use, during independent study sessions, were captured in an open-access computer laboratory. Each log consisted of a chronological sequence of tasks representing either the application or the Internet domain displayed in the workstation's active window. Each task was classified using a three-tier schema…

Task shifting between physicians and nurses in acute care hospitals: cross-sectional study in nine countries.

PubMed

Maier, Claudia B; Köppen, Julia; Busse, Reinhard

2018-05-25

Countries vary in the extent to which reforms have been implemented expanding nurses' Scopes-of-Practice (SoP). There is limited cross-country research if and how reforms affect clinical practice, particularly in hospitals. This study analyses health professionals' perceptions of role change and of task shifting between the medical and nursing professions in nine European countries. Cross-sectional design with surveys completed by 1716 health professionals treating patients with breast cancer (BC) and acute myocardial infarction (AMI) in 161 hospitals across nine countries. Descriptive and bivariate analysis on self-reported staff role changes and levels of independence (with/without physician oversight) by two country groups, with major SoP reforms implemented between 2010 and 2015 (Netherlands, England, Scotland) and without (Czech Republic, Germany, Italy, Norway, Poland, Turkey). Participation in 'medical tasks' was identified using two methods, a data-driven and a conceptual approach. Individual task-related analyses were performed for the medical and nursing professions, and Advanced Practice Nurses/Specialist Nurses (APN/SN). Health professionals from the Netherlands, England and Scotland more frequently reported changes to staff roles over this time period vs. the other six countries (BC 74.0% vs. 38.7%, p < .001; AMI 61.7% vs. 37.3%, p < .001), and higher independence in new roles (BC 58.6% vs. 24.0%, p < .001; AMI 48.9% vs. 29.2%, p < .001). A higher proportion of nurses and APN/SN from these three countries reported to undertake tasks related to BC diagnosis, therapy, prescribing of medicines and information to patients compared to the six countries. Similar cross-country differences existed for AMI on prescribing medications and follow-up care. Tasks related to diagnosis and therapy, however, remained largely within the medical profession's domain. Most tasks were reported to be performed by both professions rather than carried out by one profession only. Higher levels of changes to staff roles and task shifting were reported in the Netherlands, England and Scotland, suggesting that professional boundaries have shifted, for instance on chemotherapy or prescribing medicines. For most tasks, however, a partial instead of full task shifting is practice.

Irrelevant reward and selection histories have different influences on task-relevant attentional selection.

PubMed

MacLean, Mary H; Giesbrecht, Barry

2015-07-01

Task-relevant and physically salient features influence visual selective attention. In the present study, we investigated the influence of task-irrelevant and physically nonsalient reward-associated features on visual selective attention. Two hypotheses were tested: One predicts that the effects of target-defining task-relevant and task-irrelevant features interact to modulate visual selection; the other predicts that visual selection is determined by the independent combination of relevant and irrelevant feature effects. These alternatives were tested using a visual search task that contained multiple targets, placing a high demand on the need for selectivity, and that was data-limited and required unspeeded responses, emphasizing early perceptual selection processes. One week prior to the visual search task, participants completed a training task in which they learned to associate particular colors with a specific reward value. In the search task, the reward-associated colors were presented surrounding targets and distractors, but were neither physically salient nor task-relevant. In two experiments, the irrelevant reward-associated features influenced performance, but only when they were presented in a task-relevant location. The costs induced by the irrelevant reward-associated features were greater when they oriented attention to a target than to a distractor. In a third experiment, we examined the effects of selection history in the absence of reward history and found that the interaction between task relevance and selection history differed, relative to when the features had previously been associated with reward. The results indicate that under conditions that demand highly efficient perceptual selection, physically nonsalient task-irrelevant and task-relevant factors interact to influence visual selective attention.

Effects of accessible website design on nondisabled users: age and device as moderating factors.

PubMed

Schmutz, Sven; Sonderegger, Andreas; Sauer, Juergen

2018-05-01

This study examined how implementing recommendations from Web accessibility guidelines affects nondisabled people in different age groups using different technical devices. While recent research showed positive effects of implementing such recommendations for nondisabled users, it remains unclear whether such effects would apply to different age groups and kind of devices. A 2 × 2 × 2 design was employed with website accessibility (high accessibility vs. very low accessibility), age (younger adults vs. older adults) and type of device (laptop vs. tablet) as independent variables. 110 nondisabled participants took part in a usability test, in which performance and satisfaction were measured as dependent variables. The results showed that higher accessibility increased task completion rate, task completion time and satisfaction ratings of nondisabled users. While user age did not have any effects, users showed faster task completion time under high accessibility when using a tablet rather than a laptop. The findings confirmed previous findings, which showed benefits of accessible websites for nondisabled users. These beneficial effects may now be generalised to a wide age range and across different devices. Practitioner Summary: This work is relevant to the design of websites since it emphasises the need to consider the characteristics of different user groups. Accessible website design (aimed at users with disabilities) leads to benefits for nondisabled users across different ages. These findings provide further encouragement for practitioners to apply WCAG 2.0.

Processing of Facial Emotion in Bipolar Depression and Euthymia.

PubMed

Robinson, Lucy J; Gray, John M; Burt, Mike; Ferrier, I Nicol; Gallagher, Peter

2015-10-01

Previous studies of facial emotion processing in bipolar disorder (BD) have reported conflicting findings. In independently conducted studies, we investigate facial emotion labeling in euthymic and depressed BD patients using tasks with static and dynamically morphed images of different emotions displayed at different intensities. Study 1 included 38 euthymic BD patients and 28 controls. Participants completed two tasks: labeling of static images of basic facial emotions (anger, disgust, fear, happy, sad) shown at different expression intensities; the Eyes Test (Baron-Cohen, Wheelwright, Hill, Raste, & Plumb, 2001), which involves recognition of complex emotions using only the eye region of the face. Study 2 included 53 depressed BD patients and 47 controls. Participants completed two tasks: labeling of "dynamic" facial expressions of the same five basic emotions; the Emotional Hexagon test (Young, Perret, Calder, Sprengelmeyer, & Ekman, 2002). There were no significant group differences on any measures of emotion perception/labeling, compared to controls. A significant group by intensity interaction was observed in both emotion labeling tasks (euthymia and depression), although this effect did not survive the addition of measures of executive function/psychomotor speed as covariates. Only 2.6-15.8% of euthymic patients and 7.8-13.7% of depressed patients scored below the 10th percentile of the controls for total emotion recognition accuracy. There was no evidence of specific deficits in facial emotion labeling in euthymic or depressed BD patients. Methodological variations-including mood state, sample size, and the cognitive demands of the tasks-may contribute significantly to the variability in findings between studies.

Self-Reported Versus Performance-Based Assessments of a Simple Mobility Task Among Older Adults in the Emergency Department.

PubMed

Roedersheimer, Kyle M; Pereira, Greg F; Jones, Christopher W; Braz, Valerie A; Mangipudi, Sowmya A; Platts-Mills, Timothy F

2016-02-01

Accurate information about the mobility of independently living older adults is essential in determining whether they may be safely discharged home from the emergency department (ED). We assess the accuracy of self-reported ability to complete a simple mobility task among older ED patients. This was a cross-sectional study of cognitively intact patients aged 65 years and older who were neither nursing home residents nor critically ill, conducted in 2 academic EDs. Consenting participants were asked whether they could get out of bed, walk 10 feet, turn around, and get back in bed without assistance, and if not, whether they could perform this task with a cane, walker, or assistance. Each participant was then asked to perform the task and was provided with a mobility device or assistance as needed. Of 272 patients who met eligibility criteria and answered the physical task question, 161 (59%) said they could do the task unassisted, 45 (17%) said they could do it with a cane or walker, 21 (8%) said they could do it with assistance, and 45 (17%) said they would be unable to do it even with assistance. Among those who said they could do the task either with or without assistance and who were subsequently willing to attempt the task (N=172), discrepancies between self-reported ability and actual performance were common. Of those who said they could perform the task without assistance, 12% required some assistance or were unable to complete the task. Of those who said they could perform the task with a cane or walker, 48% required either assistance or were unable to perform the task. Of those who said they could perform the task with assistance, 24% were unable to perform the task even with assistance. In this sample of older adults receiving care in the ED, the accuracy of their self-reported ability to perform a simple mobility task was poor, particularly for those who reported some need for assistance. For older adults being considered for discharge who report a need for assistance with mobility, direct observation of the patient's mobility by a member of the emergency care team should be considered. Copyright © 2015 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

The Effect of iPad Use during Independent Practice for Students with Challenging Behavior

ERIC Educational Resources Information Center

Flower, Andrea

2014-01-01

In the classroom, time on-task is critical because it is linked to learning and success. When off-task behaviors occur, substantial learning and instructional time may be lost. Many students with disabilities struggle with remaining on-task, particularly during independent practice periods. Strategies to increase time on-task during classroom…

Predicting the role of assistive technologies in the lives of people with dementia using objective care recipient factors.

PubMed

Czarnuch, Stephen; Ricciardelli, Rose; Mihailidis, Alex

2016-07-20

The population of people with dementia is not homogeneous. People with dementia exhibit a wide range of needs, each characterized by diverse factors including age, sex, ethnicity, and place of residence. These needs and characterizing factors may influence the applicability, and ultimately the acceptance, of assistive technologies developed to support the independence of people with dementia. Accordingly, predicting the needs of users before developing the technologies may increase the applicability and acceptance of assistive technologies. Current methods of prediction rely on the difficult collection of subjective, potentially invasive information. We propose a method of prediction that uses objective, unobtrusive, easy to collect information to help inform the development of assistive technologies. We develop a set of models that can predict the level of independence of people with dementia during 20 activities of daily living using simple, objective information. Using data collected from a Canadian survey conducted with caregivers of people with dementia, we create an ordered logistic regression model for each of the twenty daily tasks in the Bristol ADL scale. Data collected from 430 Canadian caregivers of people with dementia were analyzed to reveal: most care recipients were mothers or husbands, married, living in private housing with their caregivers, English-speaking, Canadian born, clinically diagnosed with dementia 1 to 6 years prior to the study, and were dependent on their caregiver. Next, we developed models that use 13 factors to predict a person with dementia's ability to complete the 20 Bristol activities of daily living independently. The 13 factors include caregiver relation, age, marital status, place of residence, language, housing type, proximity to caregiver, service use, informal primary caregiver, diagnosis of Alzheimer's disease or dementia, time since diagnosis, and level of dependence on caregiver. The resulting models predicted the aggregate level of independence correctly for 88 of 100 total responses categories, marginally for nine, and incorrectly for three. Objective, easy to collect information can predict caregiver-reported level of task independence for a person with dementia. Knowledge of task independence can then inform the development of assistive technologies for people with dementia, improving their applicability and acceptance.

Neural reactivation links unconscious thought to decision-making performance.

PubMed

Creswell, John David; Bursley, James K; Satpute, Ajay B

2013-12-01

Brief periods of unconscious thought (UT) have been shown to improve decision making compared with making an immediate decision (ID). We reveal a neural mechanism for UT in decision making using blood oxygen level-dependent (BOLD) functional magnetic resonance imaging. Participants (N = 33) encoded information on a set of consumer products (e.g. 48 attributes describing four different cars), and we manipulated whether participants (i) consciously thought about this information (conscious thought), (ii) completed a difficult 2-back working memory task (UT) or (iii) made an immediate decision about the consumer products (ID) in a within-subjects blocked design. To differentiate UT neural activity from 2-back working memory neural activity, participants completed an independent 2-back task and this neural activity was subtracted from neural activity occurring during the UT 2-back task. Consistent with a neural reactivation account, we found that the same regions activated during the encoding of complex decision information (right dorsolateral prefrontal cortex and left intermediate visual cortex) continued to be activated during a subsequent 2-min UT period. Moreover, neural reactivation in these regions was predictive of subsequent behavioral decision-making performance after the UT period. These results provide initial evidence for post-encoding unconscious neural reactivation in facilitating decision making.

Neural reactivation links unconscious thought to decision-making performance

PubMed Central

Bursley, James K.; Satpute, Ajay B.

2013-01-01

Brief periods of unconscious thought (UT) have been shown to improve decision making compared with making an immediate decision (ID). We reveal a neural mechanism for UT in decision making using blood oxygen level-dependent (BOLD) functional magnetic resonance imaging. Participants (N = 33) encoded information on a set of consumer products (e.g. 48 attributes describing four different cars), and we manipulated whether participants (i) consciously thought about this information (conscious thought), (ii) completed a difficult 2-back working memory task (UT) or (iii) made an immediate decision about the consumer products (ID) in a within-subjects blocked design. To differentiate UT neural activity from 2-back working memory neural activity, participants completed an independent 2-back task and this neural activity was subtracted from neural activity occurring during the UT 2-back task. Consistent with a neural reactivation account, we found that the same regions activated during the encoding of complex decision information (right dorsolateral prefrontal cortex and left intermediate visual cortex) continued to be activated during a subsequent 2-min UT period. Moreover, neural reactivation in these regions was predictive of subsequent behavioral decision-making performance after the UT period. These results provide initial evidence for post-encoding unconscious neural reactivation in facilitating decision making. PMID:23314012

Interactive Multiple Object Tracking (iMOT)

PubMed Central

Thornton, Ian M.; Bülthoff, Heinrich H.; Horowitz, Todd S.; Rynning, Aksel; Lee, Seong-Whan

2014-01-01

We introduce a new task for exploring the relationship between action and attention. In this interactive multiple object tracking (iMOT) task, implemented as an iPad app, participants were presented with a display of multiple, visually identical disks which moved independently. The task was to prevent any collisions during a fixed duration. Participants could perturb object trajectories via the touchscreen. In Experiment 1, we used a staircase procedure to measure the ability to control moving objects. Object speed was set to 1°/s. On average participants could control 8.4 items without collision. Individual control strategies were quite variable, but did not predict overall performance. In Experiment 2, we compared iMOT with standard MOT performance using identical displays. Object speed was set to 2°/s. Participants could reliably control more objects (M = 6.6) than they could track (M = 4.0), but performance in the two tasks was positively correlated. In Experiment 3, we used a dual-task design. Compared to single-task baseline, iMOT performance decreased and MOT performance increased when the two tasks had to be completed together. Overall, these findings suggest: 1) There is a clear limit to the number of items that can be simultaneously controlled, for a given speed and display density; 2) participants can control more items than they can track; 3) task-relevant action appears not to disrupt MOT performance in the current experimental context. PMID:24498288

Hand Strength, Handwriting, and Functional Skills in Children With Autism.

PubMed

Alaniz, Michele L; Galit, Eleanor; Necesito, Corina Isabel; Rosario, Emily R

2015-01-01

To establish hand strength development trends in children with autism and to investigate correlations between grip and pinch strength, components of handwriting, and functional activities in children with and without autism. Fifty-one children were divided into two groups: typically developing children and children on the autism spectrum. Each child completed testing for pinch and grip strength, handwriting legibility, pencil control, and independence in functional activities. The children with autism followed the same strength development trends as the typically developing children. Grip strength correlated with pencil control in both groups and with handwriting legibility in the typically developing children but not in the children with autism. Grip and pinch strength correlated with independence with functional activities in both groups. This study provides evidence that grip and pinch strength are important components in developing pencil control, handwriting legibility, and independence with functional fine motor tasks. Copyright © 2015 by the American Occupational Therapy Association, Inc.

Mental rotation does not account for sex differences in left-right confusion.

PubMed

Ocklenburg, Sebastian; Hirnstein, Marco; Ohmann, Hanno Andreas; Hausmann, Markus

2011-06-01

Several studies have demonstrated that women believe they are more prone to left-right confusion (LRC) than men. However, while some studies report that there is also a sex difference in LRC tasks favouring men, others report that men and women perform equally well. Recently, it was suggested that sex differences only emerge in LRC tasks when they involve mental rotation. That is, sex differences that are reported for some LRC tasks are strongly affected by the well-documented male advantage in mental rotation. To test this assumption, 91 participants were investigated on two LRC tasks: The Left-Right Commands Task and the Bergen Left-Right Discrimination Test. Additionally, participants were asked to complete an LRC self-rating questionnaire. To rule out the possibility that sex differences in LRC are confounded by sex differences in mental rotation, male and female participants were matched for mental rotation performance, resulting in a sample of 46 matched participants. These matched participants showed robust sex differences in favour of men in all LRC measurements. This suggests that pronounced sex differences in LRC are a genuine phenomenon that exists independently of sex differences in mental rotation. Copyright © 2011 Elsevier Inc. All rights reserved.

Are There Age-Related Differences in the Ability to Learn Configural Responses?

PubMed Central

Clark, Rachel; Freedberg, Michael; Hazeltine, Eliot; Voss, Michelle W.

2015-01-01

Age is often associated with a decline in cognitive abilities that are important for maintaining functional independence, such as learning new skills. Many forms of motor learning appear to be relatively well preserved with age, while learning tasks that involve associative binding tend to be negatively affected. The current study aimed to determine whether age differences exist on a configural response learning task, which includes aspects of motor learning and associative binding. Young (M = 24 years) and older adults (M = 66.5 years) completed a modified version of a configural learning task. Given the requirement of associative binding in the configural relationships between responses, we predicted older adults would show significantly less learning than young adults. Older adults demonstrated lower performance (slower reaction time and lower accuracy). However, contrary to our prediction, older adults showed similar rates of learning as indexed by a configural learning score compared to young adults. These results suggest that the ability to acquire knowledge incidentally about configural response relationships is largely unaffected by cognitive aging. The configural response learning task provides insight into the task demands that constrain learning abilities in older adults. PMID:26317773

Cue combination in a combined feature contrast detection and figure identification task.

PubMed

Meinhardt, Günter; Persike, Malte; Mesenholl, Björn; Hagemann, Cordula

2006-11-01

Target figures defined by feature contrast in spatial frequency, orientation or both cues had to be detected in Gabor random fields and their shape had to be identified in a dual task paradigm. Performance improved with increasing feature contrast and was strongly correlated among both tasks. Subjects performed significantly better with combined cues than with single cues. The improvement due to cue summation was stronger than predicted by the assumption of independent feature specific mechanisms, and increased with the performance level achieved with single cues until it was limited by ceiling effects. Further, cue summation was also strongly correlated among tasks: when there was benefit due to the additional cue in feature contrast detection, there was also benefit in figure identification. For the same performance level achieved with single cues, cue summation was generally larger in figure identification than in feature contrast detection, indicating more benefit when processes of shape and surface formation are involved. Our results suggest that cue combination improves spatial form completion and figure-ground segregation in noisy environments, and therefore leads to more stable object vision.

Baseline experiments in teleoperator control

NASA Technical Reports Server (NTRS)

Hankins, W. W., III; Mixon, R. W.

1986-01-01

Studies have been conducted at the NASA Langley Research Center (LaRC) to establish baseline human teleoperator interface data and to assess the influence of some of the interface parameters on human performance in teleoperation. As baseline data, the results will be used to assess future interface improvements resulting from this research in basic teleoperator human factors. In addition, the data have been used to validate LaRC's basic teleoperator hardware setup and to compare initial teleoperator study results. Four subjects controlled a modified industrial manipulator to perform a simple task involving both high and low precision. Two different schemes for controlling the manipulator were studied along with both direct and indirect viewing of the task. Performance of the task was measured as the length of time required to complete the task along with the number of errors made in the process. Analyses of variance were computed to determine the significance of the influences of each of the independent variables. Comparisons were also made between the LaRC data and data taken earlier by Grumman Aerospace Corp. at their facilities.

Influence of Coactors on Saccadic and Manual Responses

PubMed Central

Niehorster, Diederick C.; Jarodzka, Halszka; Holmqvist, Kenneth

2017-01-01

Two experiments were conducted to investigate the effects of coaction on saccadic and manual responses. Participants performed the experiments either in a solitary condition or in a group of coactors who performed the same tasks at the same time. In Experiment 1, participants completed a pro- and antisaccade task where they were required to make saccades towards (prosaccades) or away (antisaccades) from a peripheral visual stimulus. In Experiment 2, participants performed a visual discrimination task that required both making a saccade towards a peripheral stimulus and making a manual response in reaction to the stimulus’s orientation. The results showed that performance of stimulus-driven responses was independent of the social context, while volitionally controlled responses were delayed by the presence of coactors. These findings are in line with studies assessing the effect of attentional load on saccadic control during dual-task paradigms. In particular, antisaccades – but not prosaccades – were influenced by the type of social context. Additionally, the number of coactors present in the group had a moderating effect on both saccadic and manual responses. The results support an attentional view of social influences. PMID:28321288

Evidence for modality-independent order coding in working memory.

PubMed

Depoorter, Ann; Vandierendonck, André

2009-03-01

The aim of the present study was to investigate the representation of serial order in working memory, more specifically whether serial order is coded by means of a modality-dependent or a modality-independent order code. This was investigated by means of a series of four experiments based on a dual-task methodology in which one short-term memory task was embedded between the presentation and recall of another short-term memory task. Two aspects were varied in these memory tasks--namely, the modality of the stimulus materials (verbal or visuo-spatial) and the presence of an order component in the task (an order or an item memory task). The results of this study showed impaired primary-task recognition performance when both the primary and the embedded task included an order component, irrespective of the modality of the stimulus materials. If one or both of the tasks did not contain an order component, less interference was found. The results of this study support the existence of a modality-independent order code.

Factors Contributing to Single- and Dual-Task Timed "Up & Go" Test Performance in Middle-Aged and Older Adults Who Are Active and Dwell in the Community.

PubMed

Chen, Hui-Ya; Tang, Pei-Fang

2016-03-01

Dual-task Timed "Up & Go" (TUG) tests are likely to have applications different from those of a single-task TUG test and may have different contributing factors. The purpose of this study was to compare factors contributing to performance on single- and dual-task TUG tests. This investigation was a cross-sectional study. Sixty-four adults who were more than 50 years of age and dwelled in the community were recruited. Interviews and physical examinations were performed to identify potential contributors to TUG test performance. The time to complete the single-task TUG test (TUGsingle) or the dual-task TUG test, which consisted of completing the TUG test while performing a serial subtraction task (TUGcognitive) or while carrying water (TUGmanual), was measured. Age, hip extensor strength, walking speed, general mental function, and Stroop scores for word and color were significantly associated with performance on all TUG tests. Hierarchical multiple regression models, without the input of walking speed, revealed different independent factors contributing to TUGsingle performance (Mini-Mental Status Examination score, β=-0.32), TUGmanual performance (age, β=0.35), and TUGcognitive performance (Stroop word score, β=-0.40; Mini-Mental Status Examination score, β=-0.31). At least 40% of the variance in the performance on the 3 TUG tests was not explained by common clinical measures, even when the factor of walking speed was considered. However, this study successfully identified some important factors contributing to performance on different TUG tests, and other studies have reported similar findings for single-task TUG test and dual-task gait performance. Although the TUGsingle and the TUGcognitive shared general mental function as a common factor, the TUGmanual was uniquely influenced by age and the TUGcognitive was uniquely influenced by focused attention. These results suggest that both common and unique factors contribute to performance on single- and dual-task TUG tests and suggest important applications of the combined use of the 3 TUG tests. © 2016 American Physical Therapy Association.

Teaching adolescents with severe disabilities to use the public telephone.

PubMed

Test, D W; Spooner, F; Keul, P K; Grossi, T

1990-04-01

Two adolescents with severe disabilities served as participants in a study conducted to train in the use of the public telephone to call home. Participants were trained to complete a 17-step task analysis using a training package which consisted of total task presentation in conjunction with a four-level prompting procedure (i.e., independent, verbal, verbal + gesture, verbal + guidance). All instruction took place in a public setting (e.g., a shopping mall) with generalization probes taken in two alternative settings (e.g., a movie theater and a convenience store). A multiple probe across individuals design demonstrated the training package was successful in teaching participants to use the telephone to call home. In addition, newly acquired skills generalized to the two untrained settings. Implications for community-based training are discussed.

Space station automation of common module power management and distribution

NASA Technical Reports Server (NTRS)

Miller, W.; Jones, E.; Ashworth, B.; Riedesel, J.; Myers, C.; Freeman, K.; Steele, D.; Palmer, R.; Walsh, R.; Gohring, J.

1989-01-01

The purpose is to automate a breadboard level Power Management and Distribution (PMAD) system which possesses many functional characteristics of a specified Space Station power system. The automation system was built upon 20 kHz ac source with redundancy of the power buses. There are two power distribution control units which furnish power to six load centers which in turn enable load circuits based upon a system generated schedule. The progress in building this specified autonomous system is described. Automation of Space Station Module PMAD was accomplished by segmenting the complete task in the following four independent tasks: (1) develop a detailed approach for PMAD automation; (2) define the software and hardware elements of automation; (3) develop the automation system for the PMAD breadboard; and (4) select an appropriate host processing environment.

Correlation of within-individual fluctuation of depressed mood with prefrontal cortex activity during verbal working memory task: optical topography study

NASA Astrophysics Data System (ADS)

Sato, Hiroki; Aoki, Ryuta; Katura, Takusige; Matsuda, Ryoichi; Koizumi, Hideaki

2011-12-01

Previous studies showed that interindividual variations in mood state are associated with prefrontal cortex (PFC) activity. In this study, we focused on the depressed-mood state under natural circumstances and examined the relationship between within-individual changes over time in this mood state and PFC activity. We used optical topography (OT), a functional imaging technique based on near-infrared spectroscopy, to measure PFC activity for each participant in three experimental sessions repeated at 2-week intervals. In each session, the participants completed a self-report questionnaire of mood state and underwent OT measurement while performing verbal and spatial working memory (WM) tasks. The results showed that changes in the depressed-mood score between successive sessions were negatively correlated with those in the left PFC activation for the verbal WM task (ρ = -0.56, p < 0.05). In contrast, the PFC activation for the spatial WM task did not co-vary with participants' mood changes. We thus demonstrated that PFC activity during a verbal WM task varies depending on the participant's depressed mood state, independent of trait factors. This suggests that using optical topography to measure PFC activity during a verbal WM task can be used as a potential state marker for an individual's depressed mood state.

High-Tech or Low-Tech? Comparing Self-Monitoring Systems to Increase Task Independence for Students with Autism

ERIC Educational Resources Information Center

Bouck, Emily C.; Savage, Melissa; Meyer, Nancy K.; Taber-Doughty, Teresa; Hunley, Megan

2014-01-01

Independence is the ultimate goal for students with disabilities, including secondary students with autism. One avenue targeted for increasing independence and decreasing prompt-dependency is through self-monitoring. In this study, investigators sought to determine whether a difference exists in levels of task independence when three students with…

External validation of Global Evaluative Assessment of Robotic Skills (GEARS).

PubMed

Aghazadeh, Monty A; Jayaratna, Isuru S; Hung, Andrew J; Pan, Michael M; Desai, Mihir M; Gill, Inderbir S; Goh, Alvin C

2015-11-01

We demonstrate the construct validity, reliability, and utility of Global Evaluative Assessment of Robotic Skills (GEARS), a clinical assessment tool designed to measure robotic technical skills, in an independent cohort using an in vivo animal training model. Using a cross-sectional observational study design, 47 voluntary participants were categorized as experts (>30 robotic cases completed as primary surgeon) or trainees. The trainee group was further divided into intermediates (≥5 but ≤30 cases) or novices (<5 cases). All participants completed a standardized in vivo robotic task in a porcine model. Task performance was evaluated by two expert robotic surgeons and self-assessed by the participants using the GEARS assessment tool. Kruskal-Wallis test was used to compare the GEARS performance scores to determine construct validity; Spearman's rank correlation measured interobserver reliability; and Cronbach's alpha was used to assess internal consistency. Performance evaluations were completed on nine experts and 38 trainees (14 intermediate, 24 novice). Experts demonstrated superior performance compared to intermediates and novices overall and in all individual domains (p < 0.0001). In comparing intermediates and novices, the overall performance difference trended toward significance (p = 0.0505), while the individual domains of efficiency and autonomy were significantly different between groups (p = 0.0280 and 0.0425, respectively). Interobserver reliability between expert ratings was confirmed with a strong correlation observed (r = 0.857, 95 % CI [0.691, 0.941]). Experts and participant scoring showed less agreement (r = 0.435, 95 % CI [0.121, 0.689] and r = 0.422, 95 % CI [0.081, 0.0672]). Internal consistency was excellent for experts and participants (α = 0.96, 0.98, 0.93). In an independent cohort, GEARS was able to differentiate between different robotic skill levels, demonstrating excellent construct validity. As a standardized assessment tool, GEARS maintained consistency and reliability for an in vivo robotic surgical task and may be applied for skills evaluation in a broad range of robotic procedures.

Do you really represent my task? Sequential adaptation effects to unexpected events support referential coding for the joint Simon effect.

PubMed

Klempova, Bibiana; Liepelt, Roman

2016-07-01

Recent findings suggest that a Simon effect (SE) can be induced in Individual go/nogo tasks when responding next to an event-producing object salient enough to provide a reference for the spatial coding of one's own action. However, there is skepticism against referential coding for the joint Simon effect (JSE) by proponents of task co-representation. In the present study, we tested assumptions of task co-representation and referential coding by introducing unexpected double response events in a joint go/nogo and a joint independent go/nogo task. In Experiment 1b, we tested if task representations are functionally similar in joint and standard Simon tasks. In Experiment 2, we tested sequential updating of task co-representation after unexpected single response events in the joint independent go/nogo task. Results showed increased JSEs following unexpected events in the joint go/nogo and joint independent go/nogo task (Experiment 1a). While the former finding is in line with the assumptions made by both accounts (task co-representation and referential coding), the latter finding supports referential coding. In contrast to Experiment 1a, we found a decreased SE after unexpected events in the standard Simon task (Experiment 1b), providing evidence against the functional equivalence assumption between joint and two-choice Simon tasks of the task co-representation account. Finally, we found an increased JSE also following unexpected single response events (Experiment 2), ruling out that the findings of the joint independent go/nogo task in Experiment 1a were due to a re-conceptualization of the task situation. In conclusion, our findings support referential coding also for the joint Simon effect.

Smartphone App-Based Assessment of Gait During Normal and Dual-Task Walking: Demonstration of Validity and Reliability.

PubMed

Manor, Brad; Yu, Wanting; Zhu, Hao; Harrison, Rachel; Lo, On-Yee; Lipsitz, Lewis; Travison, Thomas; Pascual-Leone, Alvaro; Zhou, Junhong

2018-01-30

Walking is a complex cognitive motor task that is commonly completed while performing another task such as talking or making decisions. Gait assessments performed under normal and "dual-task" walking conditions thus provide important insights into health. Such assessments, however, are limited primarily to laboratory-based settings. The objective of our study was to create and test a smartphone-based assessment of normal and dual-task walking for use in nonlaboratory settings. We created an iPhone app that used the phone's motion sensors to record movements during walking under normal conditions and while performing a serial-subtraction dual task, with the phone placed in the user's pants pocket. The app provided the user with multimedia instructions before and during the assessment. Acquired data were automatically uploaded to a cloud-based server for offline analyses. A total of 14 healthy adults completed 2 laboratory visits separated by 1 week. On each visit, they used the app to complete three 45-second trials each of normal and dual-task walking. Kinematic data were collected with the app and a gold-standard-instrumented GAITRite mat. Participants also used the app to complete normal and dual-task walking trials within their homes on 3 separate days. Within laboratory-based trials, GAITRite-derived heel strikes and toe-offs of the phone-side leg aligned with smartphone acceleration extrema, following filtering and rotation to the earth coordinate system. We derived stride times-a clinically meaningful metric of locomotor control-from GAITRite and app data, for all strides occurring over the GAITRite mat. We calculated stride times and the dual-task cost to the average stride time (ie, percentage change from normal to dual-task conditions) from both measurement devices. We calculated similar metrics from home-based app data. For these trials, periods of potential turning were identified via custom-developed algorithms and omitted from stride-time analyses. Across all detected strides in the laboratory, stride times derived from the app and GAITRite mat were highly correlated (P<.001, r 2 =.98). These correlations were independent of walking condition and pocket tightness. App- and GAITRite-derived stride-time dual-task costs were also highly correlated (P<.001, r 2 =.95). The error of app-derived stride times (mean 16.9, SD 9.0 ms) was unaffected by the magnitude of stride time, walking condition, or pocket tightness. For both normal and dual-task trials, average stride times derived from app walking trials demonstrated excellent test-retest reliability within and between both laboratory and home-based assessments (intraclass correlation coefficient range .82-.94). The iPhone app we created enabled valid and reliable assessment of stride timing-with the smartphone in the pocket-during both normal and dual-task walking and within both laboratory and nonlaboratory environments. Additional work is warranted to expand the functionality of this tool to older adults and other patient populations. ©Brad Manor, Wanting Yu, Hao Zhu, Rachel Harrison, On-Yee Lo, Lewis Lipsitz, Thomas Travison, Alvaro Pascual-Leone, Junhong Zhou. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 30.01.2018.

Threat prompts defensive brain responses independently of attentional control.

PubMed

Pichon, Swann; de Gelder, Beatrice; Grèzes, Julie

2012-02-01

Negative emotional signals are known to influence task performance, but so far, investigations have focused on how emotion interacts with perceptual processes by mobilizing attentional resources. The attention-independent effects of negative emotional signals are less well understood. Here, we show that threat signals trigger defensive responses independently of what observers pay attention to. Participants were scanned using functional magnetic resonance imaging while watching short video clips of threatening actions and performed either color or emotion judgments. Seeing threatening actions interfered with performance in both tasks. Amygdala activation reflected both stimulus and task conditions. In contrast, threat stimuli prompted a constant activity in a network underlying reflexive defensive behavior (periaqueductal gray, hypothalamus, and premotor cortex). Threat stimuli also disrupted ongoing behavior and provoked motor conflict in prefrontal regions during both tasks. The present results are consistent with the view that emotions trigger adaptive action tendencies independently of task settings.

Gaining control: changing relations between executive control and processing speed and their relevance for mathematics achievement over course of the preschool period

PubMed Central

Clark, Caron A. C.; Nelson, Jennifer Mize; Garza, John; Sheffield, Tiffany D.; Wiebe, Sandra A.; Espy, Kimberly Andrews

2014-01-01

Early executive control (EC) predicts a range of academic outcomes and shows particularly strong associations with children's mathematics achievement. Nonetheless, a major challenge for EC research lies in distinguishing EC from related cognitive constructs that also are linked to achievement outcomes. Developmental cascade models suggest that children's information processing speed is a driving mechanism in cognitive development that supports gains in working memory, inhibitory control and associated cognitive abilities. Accordingly, individual differences in early executive task performance and their relation to mathematics may reflect, at least in part, underlying variation in children's processing speed. The aims of this study were to: (1) examine the degree of overlap between EC and processing speed at different preschool age points; and (2) determine whether EC uniquely predicts children's mathematics achievement after accounting for individual differences in processing speed. As part of a longitudinal, cohort-sequential study, 388 children (50% boys; 44% from low income households) completed the same battery of EC tasks at ages 3, 3.75, 4.5, and 5.25 years. Several of the tasks incorporated baseline speeded naming conditions with minimal EC demands. Multidimensional latent models were used to isolate the variance in executive task performance that did not overlap with baseline processing speed, covarying for child language proficiency. Models for separate age points showed that, while EC did not form a coherent latent factor independent of processing speed at age 3 years, it did emerge as a distinct factor by age 5.25. Although EC at age 3 showed no distinct relation with mathematics achievement independent of processing speed, EC at ages 3.75, 4.5, and 5.25 showed independent, prospective links with mathematics achievement. Findings suggest that EC and processing speed are tightly intertwined in early childhood. As EC becomes progressively decoupled from processing speed with age, it begins to take on unique, discriminative importance for children's mathematics achievement. PMID:24596563

Evaluating Prototype Tasks and Alternative Rating Schemes for a New ESL Writing Test through G-Theory

ERIC Educational Resources Information Center

Lee, Yong-Won; Kantor, Robert

2007-01-01

Possible integrated and independent tasks were pilot tested for the writing section of a new generation of the TOEFL[R] (Test of English as a Foreign Language[TM]). This study examines the impact of various rating designs and of the number of tasks and raters on the reliability of writing scores based on integrated and independent tasks from the…

3D joystick for robotic arm control by individuals with high level spinal cord injuries.

PubMed

Jiang, Hairong; Wachs, Juan P; Pendergast, Martin; Duerstock, Bradley S

2013-06-01

An innovative 3D joystick was developed to enable quadriplegics due to spinal cord injuries (SCIs) to more independently and efficiently operate a robotic arm as an assistive device. The 3D joystick was compared to two different manual input modalities, a keyboard control and a traditional joystick, in performing experimental robotic arm tasks by both subjects without disabilities and those with upper extremity mobility impairments. Fitts's Law targeting and practical pouring tests were conducted to compare the performance and accuracy of the proposed 3D joystick. The Fitts's law measurements showed that the 3D joystick had the best index of performance (IP), though it required an equivalent number of operations and errors as the standard robotic arm joystick. The pouring task demonstrated that the 3D joystick took significantly less task completion time and was more accurate than keyboard control. The 3D joystick also showed a decreased learning curve to the other modalities.

AAPM Task Group 103 report on peer review in clinical radiation oncology physics

PubMed Central

Halvorsen, Per H.; Das, Indra J.; Fraser, Martin; Freedman, D. Jay; Rice, Robert E.; Ibbott, Geoffrey S.; Parsai, E. Ishmael; Robin, T. Tydings; Thomadsen, Bruce R.

2005-01-01

This report provides guidelines for a peer review process between two clinical radiation oncology physicists. While the Task Group's work was primarily focused on ensuring timely and productive independent reviews for physicists in solo practice, these guidelines may also be appropriate for physicists in a group setting, particularly when dispersed over multiple separate clinic locations. To ensure that such reviews enable a collegial exchange of professional ideas and productive critique of the entire clinical physics program, the reviews should not be used as an employee evaluation instrument by the employer. Such use is neither intended nor supported by this Task Group. Detailed guidelines are presented on the minimum content of such reviews, as well as a recommended format for reporting the findings of a review. In consideration of the full schedules faced by most clinical physicists, the process outlined herein was designed to be completed in one working day. PACS numbers: 87.53.Xd, 87.90.+y PMID:16421500

Using mixed-initiative human-robot interaction to bound performance in a search task

DOE Office of Scientific and Technical Information (OSTI.GOV)

Curtis W. Nielsen; Douglas A. Few; Devin S. Athey

2008-12-01

Mobile robots are increasingly used in dangerous domains, because they can keep humans out of harm’s way. Despite their advantages in hazardous environments, their general acceptance in other less dangerous domains has not been apparent and, even in dangerous environments, robots are often viewed as a “last-possible choice.” In order to increase the utility and acceptance of robots in hazardous domains researchers at the Idaho National Laboratory have both developed and tested novel mixed-initiative solutions that support the human-robot interactions. In a recent “dirty-bomb” experiment, participants exhibited different search strategies making it difficult to determine any performance benefits. This papermore » presents a method for categorizing the search patterns and shows that the mixed-initiative solution decreased the time to complete the task and decreased the performance spread between participants independent of prior training and of individual strategies used to accomplish the task.« less

Short Vigilance Tasks are Hard Work Even If Time Flies

DTIC Science & Technology

2016-10-21

maintaining the data needed , and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other...actual time. Upon completion of the task, participants filled out questionnaires related to the hedonic and temporal evaluation of the task. Participants...time. Upon completion of the task, participants filled out questionnaires related to the hedonic and temporal evaluation of the task. Participants

Smartphone App–Based Assessment of Gait During Normal and Dual-Task Walking: Demonstration of Validity and Reliability

PubMed Central

Yu, Wanting; Zhu, Hao; Harrison, Rachel; Lo, On-Yee; Lipsitz, Lewis; Travison, Thomas; Pascual-Leone, Alvaro; Zhou, Junhong

2018-01-01

Background Walking is a complex cognitive motor task that is commonly completed while performing another task such as talking or making decisions. Gait assessments performed under normal and “dual-task” walking conditions thus provide important insights into health. Such assessments, however, are limited primarily to laboratory-based settings. Objective The objective of our study was to create and test a smartphone-based assessment of normal and dual-task walking for use in nonlaboratory settings. Methods We created an iPhone app that used the phone’s motion sensors to record movements during walking under normal conditions and while performing a serial-subtraction dual task, with the phone placed in the user’s pants pocket. The app provided the user with multimedia instructions before and during the assessment. Acquired data were automatically uploaded to a cloud-based server for offline analyses. A total of 14 healthy adults completed 2 laboratory visits separated by 1 week. On each visit, they used the app to complete three 45-second trials each of normal and dual-task walking. Kinematic data were collected with the app and a gold-standard–instrumented GAITRite mat. Participants also used the app to complete normal and dual-task walking trials within their homes on 3 separate days. Within laboratory-based trials, GAITRite-derived heel strikes and toe-offs of the phone-side leg aligned with smartphone acceleration extrema, following filtering and rotation to the earth coordinate system. We derived stride times—a clinically meaningful metric of locomotor control—from GAITRite and app data, for all strides occurring over the GAITRite mat. We calculated stride times and the dual-task cost to the average stride time (ie, percentage change from normal to dual-task conditions) from both measurement devices. We calculated similar metrics from home-based app data. For these trials, periods of potential turning were identified via custom-developed algorithms and omitted from stride-time analyses. Results Across all detected strides in the laboratory, stride times derived from the app and GAITRite mat were highly correlated (P<.001, r2=.98). These correlations were independent of walking condition and pocket tightness. App- and GAITRite-derived stride-time dual-task costs were also highly correlated (P<.001, r2=.95). The error of app-derived stride times (mean 16.9, SD 9.0 ms) was unaffected by the magnitude of stride time, walking condition, or pocket tightness. For both normal and dual-task trials, average stride times derived from app walking trials demonstrated excellent test-retest reliability within and between both laboratory and home-based assessments (intraclass correlation coefficient range .82-.94). Conclusions The iPhone app we created enabled valid and reliable assessment of stride timing—with the smartphone in the pocket—during both normal and dual-task walking and within both laboratory and nonlaboratory environments. Additional work is warranted to expand the functionality of this tool to older adults and other patient populations. PMID:29382625

The Montreal Imaging Stress Task: using functional imaging to investigate the effects of perceiving and processing psychosocial stress in the human brain

PubMed Central

Dedovic, Katarina; Renwick, Robert; Mahani, Najmeh Khalili; Engert, Veronika; Lupien, Sonia J.; Pruessner, Jens C.

2005-01-01

Objective We developed a protocol for inducing moderate psychologic stress in a functional imaging setting and evaluated the effects of stress on physiology and brain activation. Methods The Montreal Imaging Stress Task (MIST), derived from the Trier Mental Challenge Test, consists of a series of computerized mental arithmetic challenges, along with social evaluative threat components that are built into the program or presented by the investigator. To allow the effects of stress and mental arithmetic to be investigated separately, the MIST has 3 test conditions (rest, control and experimental), which can be presented in either a block or an event-related design, for use with functional magnetic resonance imaging (fMRI) or positron emission tomography (PET). In the rest condition, subjects look at a static computer screen on which no tasks are shown. In the control condition, a series of mental arithmetic tasks are displayed on the computer screen, and subjects submit their answers by means of a response interface. In the experimental condition, the difficulty and time limit of the tasks are manipulated to be just beyond the individual's mental capacity. In addition, in this condition the presentation of the mental arithmetic tasks is supplemented by a display of information on individual and average performance, as well as expected performance. Upon completion of each task, the program presents a performance evaluation to further increase the social evaluative threat of the situation. Results In 2 independent studies using PET and a third independent study using fMRI, with a total of 42 subjects, levels of salivary free cortisol for the whole group were significantly increased under the experimental condition, relative to the control and rest conditions. Performing mental arithmetic was linked to activation of motor and visual association cortices, as well as brain structures involved in the performance of these tasks (e.g., the angular gyrus). Conclusions We propose the MIST as a tool for investigating the effects of perceiving and processing psychosocial stress in functional imaging studies. PMID:16151536

Topical Knowledge in L2 Speaking Assessment: Comparing Independent and Integrated Speaking Test Tasks

ERIC Educational Resources Information Center

Huang, Heng-Tsung Danny; Hung, Shao-Ting Alan; Plakans, Lia

2018-01-01

Integrated speaking test tasks (integrated tasks) provide reading and/or listening input to serve as the basis for test-takers to formulate their oral responses. This study examined the influence of topical knowledge on integrated speaking test performance and compared independent speaking test performance and integrated speaking test performance…

W-state Analyzer and Multi-party Measurement-device-independent Quantum Key Distribution

PubMed Central

Zhu, Changhua; Xu, Feihu; Pei, Changxing

2015-01-01

W-state is an important resource for many quantum information processing tasks. In this paper, we for the first time propose a multi-party measurement-device-independent quantum key distribution (MDI-QKD) protocol based on W-state. With linear optics, we design a W-state analyzer in order to distinguish the four-qubit W-state. This analyzer constructs the measurement device for four-party MDI-QKD. Moreover, we derived a complete security proof of the four-party MDI-QKD, and performed a numerical simulation to study its performance. The results show that four-party MDI-QKD is feasible over 150 km standard telecom fiber with off-the-shelf single photon detectors. This work takes an important step towards multi-party quantum communication and a quantum network. PMID:26644289

Visuospatial perception in children born preterm with no major neurological disorders.

PubMed

Butcher, Phillipa R; Bouma, Anke; Stremmelaar, Elisabeth F; Bos, Arend F; Smithson, Michael; Van Braeckel, Koenraad N J A

2012-11-01

Many investigations have found deficits in visuospatial perception in children born preterm, however, it is not clear whether the deficits are specific to visuospatial perception or the consequences of deficits in other functional areas, which often accompany preterm birth. This study investigated whether children born preterm show a specific deficit in visuospatial perception. Fifty-six 7- to 11-year-old preterm born children (gestational age <34 weeks) without cerebral palsy and 51 age-matched, full-term children completed four computerized tasks tapping different levels and types of visuospatial perception. Accuracy and speed of responses were recorded. Task formats were designed to reduce demands on attentional deployment. Measures of intelligence and parental education were included in the analysis. Children born preterm performed less accurately and/or less rapidly on all tasks. Their poorer performance did not reflect differences in speed-accuracy trade-off. Parental education and IQ, both significantly lower in the preterm children, contributed positively to performance on all tasks. IQ mediated the association between preterm birth and visuospatial performance on the most cognitively demanding task. Children born preterm performed more poorly than full-term controls on four visuospatial perceptual tasks. Although intelligence and parental education were also associated with performance, preterm birth contributed independently of these factors on three of four tasks. Many children born preterm are thus multiply disadvantaged on visuospatial tasks: the lower IQ scores and parental educational levels frequently found in this group increase the deficit associated with preterm birth. (c) 2012 APA, all rights reserved.

Independent component model for cognitive functions of multiple subjects using [15O]H2O PET images.

PubMed

Park, Hae-Jeong; Kim, Jae-Jin; Youn, Tak; Lee, Dong Soo; Lee, Myung Chul; Kwon, Jun Soo

2003-04-01

An independent component model of multiple subjects' positron emission tomography (PET) images is proposed to explore the overall functional components involved in a task and to explain subject specific variations of metabolic activities under altered experimental conditions utilizing the Independent component analysis (ICA) concept. As PET images represent time-compressed activities of several cognitive components, we derived a mathematical model to decompose functional components from cross-sectional images based on two fundamental hypotheses: (1) all subjects share basic functional components that are common to subjects and spatially independent of each other in relation to the given experimental task, and (2) all subjects share common functional components throughout tasks which are also spatially independent. The variations of hemodynamic activities according to subjects or tasks can be explained by the variations in the usage weight of the functional components. We investigated the plausibility of the model using serial cognitive experiments of simple object perception, object recognition, two-back working memory, and divided attention of a syntactic process. We found that the independent component model satisfactorily explained the functional components involved in the task and discuss here the application of ICA in multiple subjects' PET images to explore the functional association of brain activations. Copyright 2003 Wiley-Liss, Inc.

Is semantic priming (ir)rational? Insights from the speeded word fragment completion task.

PubMed

Heyman, Tom; Hutchison, Keith A; Storms, Gert

2016-10-01

Semantic priming, the phenomenon that a target is recognized faster if it is preceded by a semantically related prime, is a well-established effect. However, the mechanisms producing semantic priming are subject of debate. Several theories assume that the underlying processes are controllable and tuned to prime utility. In contrast, purely automatic processes, like automatic spreading activation, should be independent of the prime's usefulness. The present study sought to disentangle both accounts by creating a situation where prime processing is actually detrimental. Specifically, participants were asked to quickly complete word fragments with either the letter a or e (e.g., sh_ve to be completed as shave). Critical fragments were preceded by a prime that was either related (e.g., push) or unrelated (write) to a prohibited completion of the target (e.g., shove). In 2 experiments, we found a significant inhibitory priming effect, which is inconsistent with purely "rational" explanations of semantic priming. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Review of Bison Usage in VERA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gardner, Russell; Pawlowski, Roger P.; Clarno, Kevin T.

Bison is being used in VERA in a variety of ways; this milestone will document an independent review of the current usage of Bison and provide guidance that will improve the accuracy, performance, and consistency in the ways that Bison is used. This task will entail running a suite of small, single and multi-cycle problems with VERA-CS, followed by Bison, and Tiamat (inline) and evaluating the usage. It will also entail performing several detailed ramp to full power solutions to compare the one-way coupled solver with the fully-coupled Tiamat. This will include at least one iteration with the PHI teammore » to incorporate some of the feedback and improve the usage. This work will also be completed in conjunction with an FMC task to evaluate the ability of Bison to model load-follow in a PWR« less

Development and evaluation of a decision-based simulation for assessment of team skills.

PubMed

Andrew, Brandon; Plachta, Stephen; Salud, Lawrence; Pugh, Carla M

2012-08-01

There is a need to train and evaluate a wide variety of nontechnical surgical skills. The goal of this project was to develop and evaluate a decision-based simulation to assess team skills. The decision-based exercise used our previously validated Laparoscopic Ventral Hernia simulator and a newly developed team evaluation survey. Five teams of 3 surgical residents (N = 15) were tasked with repairing a 10 × 10-cm right upper quadrant hernia. During the simulation, independent observers (N = 6) completed a 6-item survey assessing: (1) work quality; (2) communication; and (3) team effectiveness. After the simulation, team members self-rated their performance by using the same survey. Survey reliability revealed a Cronbach's alpha of r = .811. Significant differences were found when we compared team members' (T) and observers' (O) ratings for communication (T = 4.33/5.00 vs O = 3.00/5.00, P < .01) and work quality (T = 4.33/5.00 vs O = 3.33/5.00, P < .05). The team with the greatest survey ratings was the only group to successfully complete the task. The team evaluation survey had good reliability and correlated with task performance on the simulator. Our current and previous work provides strong evidence that nontechnical and team related skills can be assessed without simulating a crisis situation. Copyright © 2012 Mosby, Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buchholz, B. A.

The project has two main goals: 1) Identify the types of adducts naphthalene (NA) forms with DNA and 2) determine whether adduct formation correlates with site selective tumor formation in defined subcompartments of the respiratory tract (respiratory and olfactory nasal epithelium and airways of mice, rats and rhesus monkeys). Five tasks are associated with the completion of the goals. Task 1: Contracting and Animal Use Approvals. IACUC and ACURO approvals are complete. The subcontract with UC Davis (UCD) was executed in December 2014. Task 2: Perform In Vitro Study for Goal 1. Rat and mouse samples exposures completed. Monkey samplesmore » need to be exposed in next quarter. Task 3: Perform In Vitro Study for Goal 2. Mouse and rat ex vivo exposures completed. Monkey samples need to be completed in the next quarter. Task 4: Sample Preparation and Analysis. Mouse and Rat Goal 2 samples completed. Monkey samples remain to be done for Goal 2. Rat samples completed for Goal 1. Mouse and Monkey samples for Goal 1 need to be completed. Task 5: Data Interpretation and Reporting. Poster will be presented at 2016 Society of Toxicology Meeting. Outline for paper on adduct formation complete and similar to poster for SOT meeting.« less

Strength, Multijoint Coordination, and Sensorimotor Processing Are Independent Contributors to Overall Balance Ability

PubMed Central

Lawrence, Emily L.; Cesar, Guilherme M.; Bromfield, Martha R.; Peterson, Richard; Valero-Cuevas, Francisco J.; Sigward, Susan M.

2015-01-01

For young adults, balance is essential for participation in physical activities but is often disrupted following lower extremity injury. Clinical outcome measures such as single limb balance (SLB), Y-balance (YBT), and the single limb hop and balance (SLHB) tests are commonly used to quantify balance ability following injury. Given the varying demands across tasks, it is likely that such outcome measures provide useful, although task-specific, information. But the extent to which they are independent and contribute to understanding the multiple contributors to balance is not clear. Therefore, the purpose of this study was to investigate the associations among these measures as they relate to the different contributors to balance. Thirty-seven recreationally active young adults completed measures including Vertical Jump, YBT, SLB, SLHB, and the new Lower Extremity Dexterity test. Principal components analysis revealed that these outcome measures could be thought of as quantifying the strength, multijoint coordination, and sensorimotor processing contributors to balance. Our results challenge the practice of using a single outcome measure to quantify the naturally multidimensional mechanisms for everyday functions such as balance. This multidimensional approach to, and interpretation of, multiple contributors to balance may lead to more effective, specialized training and rehabilitation regimens. PMID:26665007

"That was a good shift".

PubMed

Johnson, Anya; Nguyen, Helena; Parker, Sharon K; Groth, Markus; Coote, Steven; Perry, Lin; Way, Bruce

2017-06-19

Purpose The purpose of this paper is to investigate a boundary spanning, interprofessional collaboration between advanced practice nurses (APNs) and junior doctors to support junior doctors' learning and improve patient management during the overtime shift. Design/methodology/approach A mixed methods evaluation of an intervention in an adult tertiary referral hospital, to enhance interprofessional collaboration on overtime shifts. Phase 1 compared tasks and ward rounds on 86 intervention shifts with 106 "regular" shifts, and examined the effect on junior doctor patient management testing a model using regression techniques. Phase 2 explored the experience of the intervention for stakeholders. 91 junior doctors participated (89 percent response rate) on 192 overtime shifts. Junior doctors, APNs and senior medical professionals/administrators participated in interviews. Findings The intervention was associated with an increase in self-initiated ward rounds by junior doctors, partially explained by junior doctors completing fewer tasks skilled nurses could also complete. The intervention significantly reduced doctors' engagement in tasks carried over from day shifts as well as first year (but not more experienced) junior doctors' total tasks. Interviews suggested the initiative reduced junior doctors' work pressure and promoted a safe team climate, situation awareness, skills, confidence, and well-being. Originality/value Junior doctors overtime shifts (5 p.m. to 11 p.m.) are important, both for hospitals to maintain patient care after hours and for junior doctors to learn and develop independent clinical decision making skills. However, junior doctors frequently report finding overtime shifts challenging and stressful. Redesigning overtime shifts to facilitate interprofessional collaboration can improve patient management and junior doctors' learning and well-being.

Factors influencing self-reported vision-related activity limitation in the visually impaired.

PubMed

Tabrett, Daryl R; Latham, Keziah

2011-07-15

The use of patient-reported outcome (PRO) measures to assess self-reported difficulty in visual activities is common in patients with impaired vision. This study determines the visual and psychosocial factors influencing patients' responses to self-report measures, to aid in understanding what is being measured. One hundred visually impaired participants completed the Activity Inventory (AI), which assesses self-reported, vision-related activity limitation (VRAL) in the task domains of reading, mobility, visual information, and visual motor tasks. Participants also completed clinical tests of visual function (distance visual acuity and near reading performance both with and without low vision aids [LVAs], contrast sensitivity, visual fields, and depth discrimination), and questionnaires assessing depressive symptoms, social support, adjustment to visual loss, and personality. Multiple regression analyses identified that an acuity measure (distance or near), and, to a lesser extent, near reading performance without LVAs, visual fields, and contrast sensitivity best explained self-reported VRAL (28%-50% variance explained). Significant psychosocial correlates were depression and adjustment, explaining an additional 6% to 19% unique variance. Dependent on task domain, the parameters assessed explained 59% to 71% of the variance in self-reported VRAL. Visual function, most notably acuity without LVAs, is the best predictor of self-reported VRAL assessed by the AI. Depression and adjustment to visual loss also significantly influence self-reported VRAL, largely independent of the severity of visual loss and most notably in the less vision-specific tasks. The results suggest that rehabilitation strategies addressing depression and adjustment could improve perceived visual disability.

Effects on driving performance of interacting with an in-vehicle music player: a comparison of three interface layout concepts for information presentation.

PubMed

Mitsopoulos-Rubens, Eve; Trotter, Margaret J; Lenné, Michael G

2011-05-01

Interface design is an important factor in assessing the potential effects on safety of interacting with an in-vehicle information system while driving. In the current study, the layout of information on a visual display was manipulated to explore its effect on driving performance in the context of music selection. The comparative effects of an auditory-verbal (cognitive) task were also explored. The driving performance of 30 participants was assessed under both baseline and dual task conditions using the Lane Change Test. Concurrent completion of the music selection task with driving resulted in significant impairment to lateral driving performance (mean lane deviation and percentage of correct lane changes) relative to the baseline, and significantly greater mean lane deviation relative to the combined driving and the cognitive task condition. The magnitude of these effects on driving performance was independent of layout concept, although significant differences in subjective workload estimates and performance on the music selection task across layout concepts highlights that potential uncertainty regarding design use as conveyed through layout concept could be disadvantageous. The implications of these results for interface design and safety are discussed. Copyright © 2010 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Persistent spatial information in the frontal eye field during object-based short-term memory.

PubMed

Clark, Kelsey L; Noudoost, Behrad; Moore, Tirin

2012-08-08

Spatial attention is known to gate entry into visual short-term memory, and some evidence suggests that spatial signals may also play a role in binding features or protecting object representations during memory maintenance. To examine the persistence of spatial signals during object short-term memory, the activity of neurons in the frontal eye field (FEF) of macaque monkeys was recorded during an object-based delayed match-to-sample task. In this task, monkeys were trained to remember an object image over a brief delay, regardless of the locations of the sample or target presentation. FEF neurons exhibited visual, delay, and target period activity, including selectivity for sample location and target location. Delay period activity represented the sample location throughout the delay, despite the irrelevance of spatial information for successful task completion. Furthermore, neurons continued to encode sample position in a variant of the task in which the matching stimulus never appeared in their response field, confirming that FEF maintains sample location independent of subsequent behavioral relevance. FEF neurons also exhibited target-position-dependent anticipatory activity immediately before target onset, suggesting that monkeys predicted target position within blocks. These results show that FEF neurons maintain spatial information during short-term memory, even when that information is irrelevant for task performance.

Beyond capacity limitations II: Effects of lexical processes on word recall in verbal working memory tasks in children with and without specific language impairment

PubMed Central

Mainela-Arnold, Elina; Evans, Julia L.; Coady, Jeffry

2010-01-01

Purpose This study investigated the impact of lexical processes on target word recall in sentence span tasks in children with and without specific language impairment (SLI). Method Participants were 42 children (ages 8;2–12;3), 21 with SLI and 21 typically developing peers matched on age and nonverbal IQ. Children completed a sentence span task where target words to be recalled varied in word frequency and neighborhood density. Two measures of lexical processes were examined, the number of non-target competitor words activated during a gating task (lexical cohort competition) and word definitions. Results Neighborhood density had no effect on word recall for either group. However, both groups recalled significantly more high than low frequency words. Lexical cohort competition and specificity of semantic representations accounted for unique variance in the number of target word recalled in the SLI and CA groups combined. Conclusions Performance on verbal working memory span tasks for both SLI and CA children is influenced by word frequency, lexical cohorts, and semantic representations. Future studies need to examine the extent to which verbal working memory capacity is a cognitive construct independent of extant language knowledge representations. PMID:20705747

Grouping individual independent BOLD effects: a new way to ICA group analysis

NASA Astrophysics Data System (ADS)

Duann, Jeng-Ren; Jung, Tzyy-Ping; Sejnowski, Terrence J.; Makeig, Scott

2009-04-01

A new group analysis method to summarize the task-related BOLD responses based on independent component analysis (ICA) was presented. As opposite to the previously proposed group ICA (gICA) method, which first combined multi-subject fMRI data in either temporal or spatial domain and applied ICA decomposition only once to the combined fMRI data to extract the task-related BOLD effects, the method presented here applied ICA decomposition to the individual subjects' fMRI data to first find the independent BOLD effects specifically for each individual subject. Then, the task-related independent BOLD component was selected among the resulting independent components from the single-subject ICA decomposition and hence grouped across subjects to derive the group inference. In this new ICA group analysis (ICAga) method, one does not need to assume that the task-related BOLD time courses are identical across brain areas and subjects as used in the grand ICA decomposition on the spatially concatenated fMRI data. Neither does one need to assume that after spatial normalization, the voxels at the same coordinates represent exactly the same functional or structural brain anatomies across different subjects. These two assumptions have been problematic given the recent BOLD activation evidences. Further, since the independent BOLD effects were obtained from each individual subject, the ICAga method can better account for the individual differences in the task-related BOLD effects. Unlike the gICA approach whereby the task-related BOLD effects could only be accounted for by a single unified BOLD model across multiple subjects. As a result, the newly proposed method, ICAga, was able to better fit the task-related BOLD effects at individual level and thus allow grouping more appropriate multisubject BOLD effects in the group analysis.

How Do You Like Your Science, Wet or Dry? How Two Lab Experiences Influence Student Understanding of Science Concepts and Perceptions of Authentic Scientific Practice

PubMed Central

Munn, Maureen; Knuth, Randy; Van Horne, Katie; Shouse, Andrew W.; Levias, Sheldon

2017-01-01

This study examines how two kinds of authentic research experiences related to smoking behavior—genotyping human DNA (wet lab) and using a database to test hypotheses about factors that affect smoking behavior (dry lab)—influence students’ perceptions and understanding of scientific research and related science concepts. The study used pre and post surveys and a focus group protocol to compare students who conducted the research experiences in one of two sequences: genotyping before database and database before genotyping. Students rated the genotyping experiment to be more like real science than the database experiment, in spite of the fact that they associated more scientific tasks with the database experience than genotyping. Independent of the order of completing the labs, students showed gains in their understanding of science concepts after completion of the two experiences. There was little change in students’ attitudes toward science pre to post, as measured by the Scientific Attitude Inventory II. However, on the basis of their responses during focus groups, students developed more sophisticated views about the practices and nature of science after they had completed both research experiences, independent of the order in which they experienced them. PMID:28572181

Using Task Clarification, Graphic Feedback, And Verbal Feedback To Increase Closing-Task Completion In A Privately Owned Restaurant

PubMed Central

Weatherly, Nic L; Gravina, Nicole E

2005-01-01

An informant functional assessment was used to evaluate closing-task completion by servers and dishwashers at a restaurant. Based on the functional assessment results, an intervention consisting of task clarification, posted graphic feedback, and verbal feedback was implemented and evaluated with a multiple baseline design across two groups of employees. Results showed an increase of 15% and 38% in task completion for the two groups. PMID:15898481

Task allocation model for minimization of completion time in distributed computer systems

NASA Astrophysics Data System (ADS)

Wang, Jai-Ping; Steidley, Carl W.

1993-08-01

A task in a distributed computing system consists of a set of related modules. Each of the modules will execute on one of the processors of the system and communicate with some other modules. In addition, precedence relationships may exist among the modules. Task allocation is an essential activity in distributed-software design. This activity is of importance to all phases of the development of a distributed system. This paper establishes task completion-time models and task allocation models for minimizing task completion time. Current work in this area is either at the experimental level or without the consideration of precedence relationships among modules. The development of mathematical models for the computation of task completion time and task allocation will benefit many real-time computer applications such as radar systems, navigation systems, industrial process control systems, image processing systems, and artificial intelligence oriented systems.

Modality independence of order coding in working memory: Evidence from cross-modal order interference at recall.

PubMed

Vandierendonck, André

2016-01-01

Working memory researchers do not agree on whether order in serial recall is encoded by dedicated modality-specific systems or by a more general modality-independent system. Although previous research supports the existence of autonomous modality-specific systems, it has been shown that serial recognition memory is prone to cross-modal order interference by concurrent tasks. The present study used a serial recall task, which was performed in a single-task condition and in a dual-task condition with an embedded memory task in the retention interval. The modality of the serial task was either verbal or visuospatial, and the embedded tasks were in the other modality and required either serial or item recall. Care was taken to avoid modality overlaps during presentation and recall. In Experiment 1, visuospatial but not verbal serial recall was more impaired when the embedded task was an order than when it was an item task. Using a more difficult verbal serial recall task, verbal serial recall was also more impaired by another order recall task in Experiment 2. These findings are consistent with the hypothesis of modality-independent order coding. The implications for views on short-term recall and the multicomponent view of working memory are discussed.

Working memory capacity and redundant information processing efficiency.

PubMed

Endres, Michael J; Houpt, Joseph W; Donkin, Chris; Finn, Peter R

2015-01-01

Working memory capacity (WMC) is typically measured by the amount of task-relevant information an individual can keep in mind while resisting distraction or interference from task-irrelevant information. The current research investigated the extent to which differences in WMC were associated with performance on a novel redundant memory probes (RMP) task that systematically varied the amount of to-be-remembered (targets) and to-be-ignored (distractor) information. The RMP task was designed to both facilitate and inhibit working memory search processes, as evidenced by differences in accuracy, response time, and Linear Ballistic Accumulator (LBA) model estimates of information processing efficiency. Participants (N = 170) completed standard intelligence tests and dual-span WMC tasks, along with the RMP task. As expected, accuracy, response-time, and LBA model results indicated memory search and retrieval processes were facilitated under redundant-target conditions, but also inhibited under mixed target/distractor and redundant-distractor conditions. Repeated measures analyses also indicated that, while individuals classified as high (n = 85) and low (n = 85) WMC did not differ in the magnitude of redundancy effects, groups did differ in the efficiency of memory search and retrieval processes overall. Results suggest that redundant information reliably facilitates and inhibits the efficiency or speed of working memory search, and these effects are independent of more general limits and individual differences in the capacity or space of working memory.

Enhancing independent time-management skills of individuals with mental retardation using a Palmtop personal computer.

PubMed

Davies, Daniel K; Stock, Steven E; Wehmeyer, Michael L

2002-10-01

Achieving greater independence for individuals with mental retardation depends upon the acquisition of several key skills, including time-management and scheduling skills. The ability to perform tasks according to a schedule is essential to domains like independent living and employment. The use of a portable schedule prompting system to increase independence and self-regulation in time-management for individuals with mental retardation was examined. Twelve people with mental retardation participated in a comparison of their use of the technology system to perform tasks on a schedule with use of a written schedule. Results demonstrated the utility of a Palmtop computer with schedule prompting software to increase independence in the performance of vocational and daily living tasks by individuals with mental retardation.

Kinematics of self-initiated and reactive karate punches.

PubMed

Martinez de Quel, Oscar; Bennett, Simon J

2014-03-01

This study investigated whether within-task expertise affects the reported asymmetry in execution time exhibited in reactive and self-initiated movements. Karate practitioners and no-karate practitioners were compared performing a reverse punch in reaction to an external stimulus or following the intention to produce a response (self-initiated). The task was completed following the presentation of a specific (i.e., life-size image of opponent) or general stimulus and in the presence of click trains or white noise. Kinematic analyses indicated reactive movement had shorter time to peak velocity and movement time, as well as greater accuracy than self-initiated movement. These differences were independent of participant skill level although peak velocity was higher in the karate practice group than in the no-karate practice group. Reaction time (RT) of skilled participants was facilitated by a specific stimulus. There was no effect on RT or kinematic variables of the different type of auditory cues. The results of this study indicate that asymmetry in execution time of reactive and self-initiated movement holds irrespective of within-task expertise and stimulus specificity. This could have implications for training of sports and/or relearning of tasks that require rapid and accurate movements to intercept/contact a target.

Who's Who? Memory updating and character reference in children's narratives.

PubMed

Whitely, Cristy; Colozzo, Paola

2013-10-01

The capacity to update and monitor the contents of working memory is an executive function presumed to play a critical role in language processing. The current study used an individual differences approach to consider the relationship between memory updating and accurate reference to story characters in the narratives of typically developing children. English-speaking children from kindergarten to grade 2 ( N = 63; M age = 7.0 years) completed updating tasks, short-term memory tasks, and narrative productions. The authors used multiple regression to test whether updating accounted for independent variability in referential adequacy. The capacity to update working memory was related to adequate character reference beyond the effects of age and of short-term memory capacity, with the strongest relationship emerging for maintaining reference over multiple utterances. This individual differences study is the first to show a link between updating and performance in a discourse production task for young school-age children. The findings contribute to the growing body of research investigating the role of working memory in shaping language production. This study invites extension to children of different ages and language abilities as well as to other language production tasks.

Low visual information-processing speed and attention are predictors of fatigue in elementary and junior high school students

PubMed Central

2011-01-01

Background Fatigue is a common complaint among elementary and junior high school students, and is known to be associated with reduced academic performance. Recently, we demonstrated that fatigue was correlated with decreased cognitive function in these students. However, no studies have identified cognitive predictors of fatigue. Therefore, we attempted to determine independent cognitive predictors of fatigue in these students. Methods We performed a prospective cohort study. One hundred and forty-two elementary and junior high school students without fatigue participated. They completed a variety of paper-and-pencil tests, including list learning and list recall tests, kana pick-out test, semantic fluency test, figure copying test, digit span forward test, and symbol digit modalities test. The participants also completed computerized cognitive tests (tasks A to E on the modified advanced trail making test). These cognitive tests were used to evaluate motor- and information-processing speed, immediate and delayed memory function, auditory and visual attention, divided and switching attention, retrieval of learned material, and spatial construction. One year after the tests, a questionnaire about fatigue (Japanese version of the Chalder Fatigue Scale) was administered to all the participants. Results After the follow-up period, we confirmed 40 cases of fatigue among 118 students. In multivariate logistic regression analyses adjusted for grades and gender, poorer performance on visual information-processing speed and attention tasks was associated with increased risk of fatigue. Conclusions Reduced visual information-processing speed and poor attention are independent predictors of fatigue in elementary and junior high school students. PMID:21672212

Mental rotation versus invariant features in object perception from different viewpoints: an fMRI study.

PubMed

Vanrie, Jan; Béatse, Erik; Wagemans, Johan; Sunaert, Stefan; Van Hecke, Paul

2002-01-01

It has been proposed that object perception can proceed through different routes, which can be situated on a continuum ranging from complete viewpoint-dependency to complete viewpoint-independency, depending on the objects and the task at hand. Although these different routes have been extensively demonstrated on the behavioral level, the corresponding distinction in the underlying neural substrate has not received the same attention. Our goal was to disentangle, on the behavioral and the neurofunctional level, a process associated with extreme viewpoint-dependency, i.e. mental rotation, and a process associated with extreme viewpoint-independency, i.e. the use of viewpoint-invariant, diagnostic features. Two sets of 3-D block figures were created that either differed in handedness (original versus mirrored) or in the angles joining the block components (orthogonal versus skewed). Behavioral measures on a same-different judgment task were predicted to be dependent on viewpoint in the rotation condition (same versus mirrored), but not in the invariance condition (same angles versus different angles). Six subjects participated in an fMRI experiment while presented with both conditions in alternating blocks. Both reaction times and accuracy confirmed the predicted dissociation between the two conditions. Neurofunctional results indicate that all cortical areas activated in the invariance condition were also activated in the rotation condition. Parietal areas were more activated than occipito-temporal areas in the rotation condition, while this pattern was reversed in the invariance condition. Furthermore, some areas were activated uniquely by the rotation condition, probably reflecting the additional processes apparent in the behavioral response patterns.

Low visual information-processing speed and attention are predictors of fatigue in elementary and junior high school students.

PubMed

Mizuno, Kei; Tanaka, Masaaki; Fukuda, Sanae; Yamano, Emi; Shigihara, Yoshihito; Imai-Matsumura, Kyoko; Watanabe, Yasuyoshi

2011-06-14

Fatigue is a common complaint among elementary and junior high school students, and is known to be associated with reduced academic performance. Recently, we demonstrated that fatigue was correlated with decreased cognitive function in these students. However, no studies have identified cognitive predictors of fatigue. Therefore, we attempted to determine independent cognitive predictors of fatigue in these students. We performed a prospective cohort study. One hundred and forty-two elementary and junior high school students without fatigue participated. They completed a variety of paper-and-pencil tests, including list learning and list recall tests, kana pick-out test, semantic fluency test, figure copying test, digit span forward test, and symbol digit modalities test. The participants also completed computerized cognitive tests (tasks A to E on the modified advanced trail making test). These cognitive tests were used to evaluate motor- and information-processing speed, immediate and delayed memory function, auditory and visual attention, divided and switching attention, retrieval of learned material, and spatial construction. One year after the tests, a questionnaire about fatigue (Japanese version of the Chalder Fatigue Scale) was administered to all the participants. After the follow-up period, we confirmed 40 cases of fatigue among 118 students. In multivariate logistic regression analyses adjusted for grades and gender, poorer performance on visual information-processing speed and attention tasks was associated with increased risk of fatigue. Reduced visual information-processing speed and poor attention are independent predictors of fatigue in elementary and junior high school students. © 2011 Mizuno et al; licensee BioMed Central Ltd.

Concurrent Path Planning with One or More Humanoid Robots

NASA Technical Reports Server (NTRS)

Reiland, Matthew J. (Inventor); Sanders, Adam M. (Inventor)

2014-01-01

A robotic system includes a controller and one or more robots each having a plurality of robotic joints. Each of the robotic joints is independently controllable to thereby execute a cooperative work task having at least one task execution fork, leading to multiple independent subtasks. The controller coordinates motion of the robot(s) during execution of the cooperative work task. The controller groups the robotic joints into task-specific robotic subsystems, and synchronizes motion of different subsystems during execution of the various subtasks of the cooperative work task. A method for executing the cooperative work task using the robotic system includes automatically grouping the robotic joints into task-specific subsystems, and assigning subtasks of the cooperative work task to the subsystems upon reaching a task execution fork. The method further includes coordinating execution of the subtasks after reaching the task execution fork.

Hand and Grasp Selection in a Preferential Reaching Task: The Effects of Object Location, Orientation, and Task Intention.

PubMed

Scharoun, Sara M; Scanlan, Kelly A; Bryden, Pamela J

2016-01-01

As numerous movement options are available in reaching and grasping, of particular interest are what factors influence an individual's choice of action. In the current study a preferential reaching task was used to assess the propensity for right handers to select their preferred hand and grasp a coffee mug by the handle in both independent and joint action object manipulation contexts. Mug location (right-space, midline, and left-space) and handle orientation (toward, away, to left, and to right of the participant) varied in four tasks that differed as a function of intention: (1) pick-up (unimanual, independent); (2) pick-up and pour (bimanual, independent); (3) pick-up and pass (unimanual, joint action); and (4) pick-up, pour and pass (bimanual, joint action). In line with previous reports, a right-hand preference for unimanual tasks was observed. Furthermore, extending existing literature to a preferential reaching task, role differentiation between the hands in bimanual tasks (i.e., preferred hand mobilizing, non-preferred hand stabilizing) was displayed. Finally, right-hand selection was greatest in right space, albeit lower in bimanual tasks compared to what is typically reported in unimanual tasks. Findings are attributed to the desire to maximize biomechanical efficiency in reaching. Grasp postures were also observed to reflect consideration of efficiency. More specifically, within independent object manipulation (pick-up; pick-up and pour) participants only grasped the mug by the handle when it afforded a comfortable posture. Furthermore, in joint action (pick-up and pass; pick-up, pour and pass), the confederate was only offered the handle if the intended action of the confederate was similar or required less effort than that of the participant. Together, findings from the current study add to our knowledge of hand and grasp selection in unimanual and bimanual object manipulation, within the context of both independent and joint action tasks.

Deadlines in space: Selective effects of coordinate spatial processing in multitasking.

PubMed

Todorov, Ivo; Del Missier, Fabio; Konke, Linn Andersson; Mäntylä, Timo

2015-11-01

Many everyday activities require coordination and monitoring of multiple deadlines. One way to handle these temporal demands might be to represent future goals and deadlines as a pattern of spatial relations. We examined the hypothesis that spatial ability, in addition to executive functioning, contributes to individual differences in multitasking. In two studies, participants completed a multitasking session in which they monitored four digital clocks running at different rates. In Study 1, we found that individual differences in spatial ability and executive functions were independent predictors of multiple-task performance. In Study 2, we found that individual differences in specific spatial abilities were selectively related to multiple-task performance, as only coordinate spatial processing, but not categorical, predicted multitasking, even beyond executive functioning and numeracy. In both studies, males outperformed females in spatial ability and multitasking and in Study 2 these sex differences generalized to a simulation of everyday multitasking. Menstrual changes moderated the effects on multitasking, in that sex differences in coordinate spatial processing and multitasking were observed between males and females in the luteal phase of the menstrual cycle, but not between males and females at menses. Overall, these findings suggest that multiple-task performance reflects independent contributions of spatial ability and executive functioning. Furthermore, our results support the distinction of categorical versus coordinate spatial processing, and suggest that these two basic relational processes are selectively affected by female sex hormones and differentially effective in transforming and handling temporal patterns as spatial relations in the context of multitasking.

Motor and executive function at 6 years of age after extremely preterm birth.

PubMed

Marlow, Neil; Hennessy, Enid M; Bracewell, Melanie A; Wolke, Dieter

2007-10-01

Studies of very preterm infants have demonstrated impairments in multiple neurocognitive domains. We hypothesized that neuromotor and executive-function deficits may independently contribute to school failure. We studied children who were born at < or = 25 completed weeks' gestation in the United Kingdom and Ireland in 1995 at early school age. Children underwent standardized cognitive and neuromotor assessments, including the Kaufman Assessment Battery for Children and NEPSY, and a teacher-based assessment of academic achievement. Of 308 surviving children, 241 (78%) were assessed at a median age of 6 years 4 months. Compared with 160 term classmates, 180 extremely preterm children without cerebral palsy and attending mainstream school performed less well on 3 simple motor tasks: posting coins, heel walking, and 1-leg standing. They more frequently had non-right-hand preferences (28% vs 10%) and more associated/overflow movements during motor tasks. Standardized scores for visuospatial and sensorimotor function performance differed from classmates by 1.6 and 1.1 SDs of the classmates' scores, respectively. These differences attenuated but remained significant after controlling for overall cognitive scores. Cognitive, visuospatial scores, and motor scores explained 54% of the variance in teachers' ratings of performance in the whole set; in the extremely preterm group, additional variance was explained by attention-executive tasks and gender. Impairment of motor, visuospatial, and sensorimotor function, including planning, self-regulation, inhibition, and motor persistence, contributes excess morbidity over cognitive impairment in extremely preterm children and contributes independently to poor classroom performance at 6 years of age.

Spatiotemporal imaging of complexity

PubMed Central

Robinson, Stephen E.; Mandell, Arnold J.; Coppola, Richard

2013-01-01

What are the functional neuroimaging measurements required for more fully characterizing the events and locations of neocortical activity? A prime assumption has been that modulation of cortical activity will inevitably be reflected in changes in energy utilization (for the most part) changes of glucose and oxygen consumption. Are such a measures complete and sufficient? More direct measures of cortical electrophysiological activity show event or task-related modulation of amplitude or band-limited oscillatory power. Using magnetoencephalography (MEG), these measures have been shown to correlate well with energy utilization sensitive BOLD fMRI. In this paper, we explore the existence of state changes in electrophysiological cortical activity that can occur independently of changes in averaged amplitude, source power or indices of metabolic rates. In addition, we demonstrate that such state changes can be described by applying a new measure of complexity, rank vector entropy (RVE), to source waveform estimates from beamformer-processed MEG. RVE is a non-parametric symbolic dynamic informational entropy measure that accommodates the wide dynamic range of measured brain signals while resolving its temporal variations. By representing the measurements by their rank values, RVE overcomes the problem of defining embedding space partitions without resorting to signal compression. This renders RVE-independent of absolute signal amplitude. In addition, this approach is robust, being relatively free of tunable parameters. We present examples of task-free and task-dependent MEG demonstrating that RVE provides new information by uncovering hidden dynamical structure in the apparent turbulent (or chaotic) dynamics of spontaneous cortical activity. PMID:23355820

Improving Closing Task Completion in a Drugstore

ERIC Educational Resources Information Center

Fante, Rhiannon; Davis, Ora L.; Kempt, Vivian

2013-01-01

A within-subject ABAB reversal design was utilized to investigate the effects of graphic feedback and goal setting on employee closing task completion. Goal setting was contingent upon baseline performance and graphic feedback was posted weekly. It was found that goal setting and graphic feedback improved employee closing task completion.…

The Nexus between the Above-Average Effect and Cooperative Learning in the Classroom

ERIC Educational Resources Information Center

Breneiser, Jennifer E.; Monetti, David M.; Adams, Katharine S.

2012-01-01

The present study examines the above-average effect (Chambers & Windschitl, 2004; Moore & Small, 2007) in assessments of task performance. Participants completed self-estimates of performance and group estimates of performance, before and after completing a task. Participants completed a task individually and in groups. Groups were…

Factors influencing the academic motivation of individual college students.

PubMed

Yoshida, Masahiro; Tanaka, Masaaki; Mizuno, Kei; Ishii, Akira; Nozaki, Kumi; Urakawa, Ayako; Cho, Yuki; Kataoka, Yosky; Watanabe, Yasuyoshi

2008-10-01

Motivation is an important psychological concept in academic learning. Subjects performed jigsaw puzzle and square puzzle sessions (as difficulty variant task) and 80%, 50%, and 20% completion sessions (as completion variant task). After square puzzle or 20% completion sessions, subjective motivation decreased. Although baseline scores on an academic motivation scale were negatively correlated with changes in subjective motivation for the square puzzle session, a positive correlation was observed for the 20% completion session. These suggest that while continual completion of facile task trials may support the motivation of college students with lower academic motivation, attempting difficult task trials may sustain that of those with higher academic motivation.

From "rest" to language task: Task activation selects and prunes from broader resting-state network.

PubMed

Doucet, Gaelle E; He, Xiaosong; Sperling, Michael R; Sharan, Ashwini; Tracy, Joseph I

2017-05-01

Resting-state networks (RSNs) show spatial patterns generally consistent with networks revealed during cognitive tasks. However, the exact degree of overlap between these networks has not been clearly quantified. Such an investigation shows promise for decoding altered functional connectivity (FC) related to abnormal language functioning in clinical populations such as temporal lobe epilepsy (TLE). In this context, we investigated the network configurations during a language task and during resting state using FC. Twenty-four healthy controls, 24 right and 24 left TLE patients completed a verb generation (VG) task and a resting-state fMRI scan. We compared the language network revealed by the VG task with three FC-based networks (seeding the left inferior frontal cortex (IFC)/Broca): two from the task (ON, OFF blocks) and one from the resting state. We found that, for both left TLE patients and controls, the RSN recruited regions bilaterally, whereas both VG-on and VG-off conditions produced more left-lateralized FC networks, matching more closely with the activated language network. TLE brings with it variability in both task-dependent and task-independent networks, reflective of atypical language organization. Overall, our findings suggest that our RSN captured bilateral activity, reflecting a set of prepotent language regions. We propose that this relationship can be best understood by the notion of pruning or winnowing down of the larger language-ready RSN to carry out specific task demands. Our data suggest that multiple types of network analyses may be needed to decode the association between language deficits and the underlying functional mechanisms altered by disease. Hum Brain Mapp 38:2540-2552, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Covariance Matrix Evaluations for Independent Mass Fission Yields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terranova, N., E-mail: nicholas.terranova@unibo.it; Serot, O.; Archier, P.

2015-01-15

Recent needs for more accurate fission product yields include covariance information to allow improved uncertainty estimations of the parameters used by design codes. The aim of this work is to investigate the possibility to generate more reliable and complete uncertainty information on independent mass fission yields. Mass yields covariances are estimated through a convolution between the multi-Gaussian empirical model based on Brosa's fission modes, which describe the pre-neutron mass yields, and the average prompt neutron multiplicity curve. The covariance generation task has been approached using the Bayesian generalized least squared method through the CONRAD code. Preliminary results on mass yieldsmore » variance-covariance matrix will be presented and discussed from physical grounds in the case of {sup 235}U(n{sub th}, f) and {sup 239}Pu(n{sub th}, f) reactions.« less

Improved application of independent component analysis to functional magnetic resonance imaging study via linear projection techniques.

PubMed

Long, Zhiying; Chen, Kewei; Wu, Xia; Reiman, Eric; Peng, Danling; Yao, Li

2009-02-01

Spatial Independent component analysis (sICA) has been widely used to analyze functional magnetic resonance imaging (fMRI) data. The well accepted implicit assumption is the spatially statistical independency of intrinsic sources identified by sICA, making the sICA applications difficult for data in which there exist interdependent sources and confounding factors. This interdependency can arise, for instance, from fMRI studies investigating two tasks in a single session. In this study, we introduced a linear projection approach and considered its utilization as a tool to separate task-related components from two-task fMRI data. The robustness and feasibility of the method are substantiated through simulation on computer data and fMRI real rest data. Both simulated and real two-task fMRI experiments demonstrated that sICA in combination with the projection method succeeded in separating spatially dependent components and had better detection power than pure model-based method when estimating activation induced by each task as well as both tasks.

Evaluation of selected auditory tests in school-age children suspected of auditory processing disorders.

PubMed

Vanniasegaram, Iyngaram; Cohen, Mazal; Rosen, Stuart

2004-12-01

To compare the auditory function of normal-hearing children attending mainstream schools who were referred for an auditory evaluation because of listening/hearing problems (suspected auditory processing disorders [susAPD]) with that of normal-hearing control children. Sixty-five children with a normal standard audiometric evaluation, ages 6-14 yr (32 of whom were referred for susAPD, with the rest age-matched control children), completed a battery of four auditory tests: a dichotic test of competing sentences; a simple discrimination of short tone pairs differing in fundamental frequency at varying interstimulus intervals (TDT); a discrimination task using consonant cluster minimal pairs of real words (CCMP), and an adaptive threshold task for detecting a brief tone presented either simultaneously with a masker (simultaneous masking) or immediately preceding it (backward masking). Regression analyses, including age as a covariate, were performed to determine the extent to which the performance of the two groups differed on each task. Age-corrected z-scores were calculated to evaluate the effectiveness of the complete battery in discriminating the groups. The performance of the susAPD group was significantly poorer than the control group on all but the masking tasks, which failed to differentiate the two groups. The CCMP discriminated the groups most effectively, as it yielded the lowest number of control children with abnormal scores, and performance in both groups was independent of age. By contrast, the proportion of control children who performed poorly on the competing sentences test was unacceptably high. Together, the CCMP (verbal) and TDT (nonverbal) tasks detected impaired listening skills in 56% of the children who were referred to the clinic, compared with 6% of the control children. Performance on the two tasks was not correlated. Two of the four tests evaluated, the CCMP and TDT, proved effective in differentiating the two groups of children of this study. The application of both tests increased the proportion of susAPD children who performed poorly compared with the application of each test alone, while reducing the proportion of control subjects who performed poorly. The findings highlight the importance of carrying out a complete auditory evaluation in children referred for medical attention, even if their standard audiometric evaluation is unremarkable.

Development of VariLeg, an exoskeleton with variable stiffness actuation: first results and user evaluation from the CYBATHLON 2016.

PubMed

Schrade, Stefan O; Dätwyler, Katrin; Stücheli, Marius; Studer, Kathrin; Türk, Daniel-Alexander; Meboldt, Mirko; Gassert, Roger; Lambercy, Olivier

2018-03-13

Powered exoskeletons are a promising approach to restore the ability to walk after spinal cord injury (SCI). However, current exoskeletons remain limited in their walking speed and ability to support tasks of daily living, such as stair climbing or overcoming ramps. Moreover, training progress for such advanced mobility tasks is rarely reported in literature. The work presented here aims to demonstrate the basic functionality of the VariLeg exoskeleton and its ability to enable people with motor complete SCI to perform mobility tasks of daily life. VariLeg is a novel powered lower limb exoskeleton that enables adjustments to the compliance in the leg, with the objective of improving the robustness of walking on uneven terrain. This is achieved by an actuation system with variable mechanical stiffness in the knee joint, which was validated through test bench experiments. The feasibility and usability of the exoskeleton was tested with two paraplegic users with motor complete thoracic lesions at Th4 and Th12. The users trained three times a week, in 60 min sessions over four months with the aim of participating in the CYBATHLON 2016 competition, which served as a field test for the usability of the exoskeleton. The progress on basic walking skills and on advanced mobility tasks such as incline walking and stair climbing is reported. Within this first study, the exoskeleton was used with a constant knee stiffness. Test bench evaluation of the variable stiffness actuation system demonstrate that the stiffness could be rendered with an error lower than 30 Nm/rad. During training with the exoskeleton, both users acquired proficient skills in basic balancing, walking and slalom walking. In advanced mobility tasks, such as climbing ramps and stairs, only basic (needing support) to intermediate (able to perform task independently in 25% of the attempts) skill levels were achieved. After 4 months of training, one user competed at the CYBATHLON 2016 and was able to perform 3 (stand-sit-stand, slalom and tilted path) out of 6 obstacles of the track. No adverse events occurred during the training or the competition. Demonstration of the applicability to restore ambulation for people with motor complete SCI was achieved. The CYBATHLON highlighted the importance of training and gaining experience in piloting an exoskeleton, which were just as important as the technical realization of the robot.

The Time on Task Effect in Reading and Problem Solving Is Moderated by Task Difficulty and Skill: Insights from a Computer-Based Large-Scale Assessment

ERIC Educational Resources Information Center

Goldhammer, Frank; Naumann, Johannes; Stelter, Annette; Tóth, Krisztina; Rölke, Heiko; Klieme, Eckhard

2014-01-01

Computer-based assessment can provide new insights into behavioral processes of task completion that cannot be uncovered by paper-based instruments. Time presents a major characteristic of the task completion process. Psychologically, time on task has 2 different interpretations, suggesting opposing associations with task outcome: Spending more…

Is lorazepam-induced amnesia specific to the type of memory or to the task used to assess it?

PubMed

File, S E; Sharma, R; Shaffer, J

1992-01-01

Retrieval tasks can be classified along a continuum from conceptually driven (relying on the encoded meaning of the material) to data driven (relying on the perceptual record and surface features of the material). Since most explicit memory tests are conceptually driven and most implicit memory tests are data driven there has been considerable confounding of the memory system being assessed and the processing required by the retrieval task. The purpose of the present experiment was to investigate the effects of lorazepam on explicit memory, using both types of retrieval task. Lorazepam (2.5 mg) or matched placebo was administered to healthy volunteers and changes in subjective mood ratings and in performance in tests of memory were measured. Lorazepam made subjects significantly more drowsy, feeble, clumsy, muzzy, lethargic and mentally slow. Lorazepam significantly impaired recognition memory for slides, impaired the number of words remembered when the retrieval was cued by the first two letters and reduced the number of pictures remembered when retention was cued with picture fragments. Thus episodic memory was impaired whether the task used was conceptually driven (as in slide recognition) or data driven, as in the other two tasks. Analyses of covariance indicated that the memory impairments were independent of increased sedation, as assessed by self-ratings. In contrast to the deficits in episodic memory, there were no lorazepam-induced impairments in tests of semantic memory, whether this was measured in the conceptually driven task of category generation or in the data-driven task of wordstem completion.

The influences of obesity and age on functional performance during intermittent upper extremity tasks.

PubMed

Cavuoto, Lora A; Nussbaum, Maury A

2014-01-01

In this study, the main and interactive effects of obesity and age on functional performance were assessed during intermittent exertions involving the upper extremity. The prevalence of obesity has doubled over the past 30 years and this increase is associated with higher health care costs, rates of workplace injury, and lost workdays. Obesity and aging can modify job demands and affect worker capacity in terms of muscular and psychomotor function. However, there is a lack of empirical studies quantifying the work-relevant (or ergonomic) impacts related to task demands, capacities, and their potential imbalance. Eight obese and eight non-obese participants from each of two age groups (18-25 and 50-65 years) completed three endurance tasks involving fixed levels of task demands: hand grip, shoulder flexion, and a simulated assembly task using the upper extremity. Measures of functional performance including endurance, discomfort, motor control, and task performance were recorded for each of the task conditions. Endurance times were ∼60% longer for the non-obese group, and older participants had longer endurance times; however there was no evidence of interactive effects of obesity and age. Obesity also impaired functional performance, as indicated by higher rates of strength loss, increases in discomfort, and declines in task performance. These observed impairments may reflect underlying physiological differences among individuals who are obese, but that are independent of age. Obesity-related impairments may have implications for the design of work duration and demand level to prevent fatigue development for workers who are obese.

Combining of ETHOS Operating Ergonomic Platform, Three-dimensional Laparoscopic Camera, and Radius Surgical System Manipulators Improves Ergonomy in Urologic Laparoscopy: Comparison with Conventional Laparoscopy and da Vinci in a Pelvi Trainer.

PubMed

Tokas, Theodoros; Gözen, Ali Serdar; Avgeris, Margaritis; Tschada, Alexandra; Fiedler, Marcel; Klein, Jan; Rassweiler, Jens

2017-10-01

Posture, vision, and instrumentation limitations are the main predicaments of conventional laparoscopy. To combine the ETHOS surgical chair, the three-dimensional laparoscope, and the Radius Surgical System manipulators, and compare the system with conventional laparoscopy and da Vinci in terms of task completion times and discomfort. Fifteen trainees performed the three main laparoscopic suturing tasks of the Heilbronn training program (IV: simulation of dorsal venous complex suturing; V: circular suturing of tubular structure; and VI: urethrovesical anastomosis) in a pelvi trainer. The tasks were performed conventionally, utilizing the three devices, and robotically. Task completion times were recorded and the surgeon discomfort was evaluated using questionnaires. Task completion times were compared using nonparametric Wilcoxon signed rank test and ergonomic scores were compared using Pearson chi-square test. The use of the full laparoscopic set (ETHOS chair, three-dimensional laparoscopic camera, Radius Surgical System needle holders), resulted in a significant improvement of the completion time of the three tested tasks compared with conventional laparoscopy (p<0.001) and similar to da Vinci surgery. After completing Tasks IV, V, and VI conventionally, 12 (80%), 13 (86.7%), and 13 (86.7%) of the 15 trainees, respectively, reported heavy total discomfort. The full laparoscopic system nullified heavy discomfort for Tasks IV and V and minimized it (6.7%) for the most demanding Task VI. Especially for Task VI, all trainees gained benefit, by using the system, in terms of task completion times and discomfort. The limited trainee robotic experience and the questionnaire subjectivity could be a potential limitation. The ergonomic laparoscopic system offers significantly improved task completion times and ergonomy than conventional laparoscopy. Furthermore, it demonstrates comparable results to robotic surgery. The study was conducted in a pelvi trainer and no patients were recruited. Copyright © 2016 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Development of the FITS tools package for multiple software environments

NASA Technical Reports Server (NTRS)

Pence, W. D.; Blackburn, J. K.

1992-01-01

The HEASARC is developing a package of general purpose software for analyzing data files in FITS format. This paper describes the design philosophy which makes the software both machine-independent (it runs on VAXs, Suns, and DEC-stations) and software environment-independent. Currently the software can be compiled and linked to produce IRAF tasks, or alternatively, the same source code can be used to generate stand-alone tasks using one of two implementations of a user-parameter interface library. The machine independence of the software is achieved by writing the source code in ANSI standard Fortran or C, using the machine-independent FITSIO subroutine interface for all data file I/O, and using a standard user-parameter subroutine interface for all user I/O. The latter interface is based on the Fortran IRAF Parameter File interface developed at STScI. The IRAF tasks are built by linking to the IRAF implementation of this parameter interface library. Two other implementations of this parameter interface library, which have no IRAF dependencies, are now available which can be used to generate stand-alone executable tasks. These stand-alone tasks can simply be executed from the machine operating system prompt either by supplying all the task parameters on the command line or by entering the task name after which the user will be prompted for any required parameters. A first release of this FTOOLS package is now publicly available. The currently available tasks are described, along with instructions on how to obtain a copy of the software.

Investigating Antecedents of Task Commitment and Task Attraction in Service Learning Team Projects

ERIC Educational Resources Information Center

Schaffer, Bryan S.; Manegold, Jennifer G.

2018-01-01

The authors investigated the antecedents of team task cohesiveness in service learning classroom environments. Focusing on task commitment and task attraction as key dependent variables representing cohesiveness, and task interdependence as the primary independent variable, the authors position three important task action phase processes as…

Kinematics effectively delineate accomplished users of endovascular robotics with a physical training model.

PubMed

Duran, Cassidy; Estrada, Sean; O'Malley, Marcia; Lumsden, Alan B; Bismuth, Jean

2015-02-01

Endovascular robotics systems, now approved for clinical use in the United States and Europe, are seeing rapid growth in interest. Determining who has sufficient expertise for safe and effective clinical use remains elusive. Our aim was to analyze performance on a robotic platform to determine what defines an expert user. During three sessions, 21 subjects with a range of endovascular expertise and endovascular robotic experience (novices <2 hours to moderate-extensive experience with >20 hours) performed four tasks on a training model. All participants completed a 2-hour training session on the robot by a certified instructor. Completion times, global rating scores, and motion metrics were collected to assess performance. Electromagnetic tracking was used to capture and to analyze catheter tip motion. Motion analysis was based on derivations of speed and position including spectral arc length and total number of submovements (inversely proportional to proficiency of motion) and duration of submovements (directly proportional to proficiency). Ninety-eight percent of competent subjects successfully completed the tasks within the given time, whereas 91% of noncompetent subjects were successful. There was no significant difference in completion times between competent and noncompetent users except for the posterior branch (151 s:105 s; P = .01). The competent users had more efficient motion as evidenced by statistically significant differences in the metrics of motion analysis. Users with >20 hours of experience performed significantly better than those newer to the system, independent of prior endovascular experience. This study demonstrates that motion-based metrics can differentiate novice from trained users of flexible robotics systems for basic endovascular tasks. Efficiency of catheter movement, consistency of performance, and learning curves may help identify users who are sufficiently trained for safe clinical use of the system. This work will help identify the learning curve and specific movements that translate to expert robotic navigation. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Daily Fluctuations in Everyday Cognition: Is It Meaningful?

PubMed

Gamaldo, Alyssa A; Allaire, Jason C

2016-08-01

This study examined whether there are daily fluctuations in everyday cognition that are consistent with daily fluctuations often observed in traditional measures of basic cognitive abilities. Two hundred six independently living older adults (age range = 60-91 years) were asked to complete a computerized cognitive battery over eight occasions within a 2- to 3-week period. Using multilevel model, significant within-person variability was observed across the Daily Everyday Cognition Assessment (DECA; 46%), with 54% between-person variability. At each occasion, better performance on the DECA was significantly associated with better performance on simple reaction time ( p < .01) and memory (Auditory Verbal Learning Task, p < .01) even after accounting for time, age, education, and performance on other cognitive measures. These findings demonstrate that within-person performance fluctuations can be observed for everyday cognition tasks, and these fluctuations are consistent with daily changes in basic cognitive abilities. © The Author(s) 2015.

Theory of mind and executive function: working-memory capacity and inhibitory control as predictors of false-belief task performance.

PubMed

Mutter, Brigitte; Alcorn, Mark B; Welsh, Marilyn

2006-06-01

This study of the relationship between theory of mind and executive function examined whether on the false-belief task age differences between 3 and 5 ears of age are related to development of working-memory capacity and inhibitory processes. 72 children completed tasks measuring false belief, working memory, and inhibition. Significant age effects were observed for false-belief and working-memory performance, as well as for the false-alarm and perseveration measures of inhibition. A simultaneous multiple linear regression specified the contribution of age, inhibition, and working memory to the prediction of false-belief performance. This model was significant, explaining a total of 36% of the variance. To examine the independent contributions of the working-memory and inhibition variables, after controlling for age, two hierarchical multiple linear regressions were conducted. These multiple regression analyses indicate that working memory and inhibition make small, overlapping contributions to false-belief performance after accounting for age, but that working memory, as measured in this study, is a somewhat better predictor of false-belief understanding than is inhibition.

Self-Administered, Home-Based SMART (Sensorimotor Active Rehabilitation Training) Arm Training: A Single-Case Report.

PubMed

Hayward, Kathryn S; Neibling, Bridee A; Barker, Ruth N

2015-01-01

This single-case, mixed-method study explored the feasibility of self-administered, home-based SMART (sensorimotor active rehabilitation training) Arm training for a 57-yr-old man with severe upper-limb disability after a right frontoparietal hemorrhagic stroke 9 mo earlier. Over 4 wk of self-administered, home-based SMART Arm training, the participant completed 2,100 repetitions unassisted. His wife provided support for equipment set-up and training progressions. Clinically meaningful improvements in arm impairment (strength), activity (arm and hand tasks), and participation (use of arm in everyday tasks) occurred after training (at 4 wk) and at follow-up (at 16 wk). Areas for refinement of SMART Arm training derived from thematic analysis of the participant's and researchers' journals focused on enabling independence, ensuring home and user friendliness, maintaining the motivation to persevere, progressing toward everyday tasks, and integrating practice into daily routine. These findings suggest that further investigation of self-administered, home-based SMART Arm training is warranted for people with stroke who have severe upper-limb disability. Copyright © 2015 by the American Occupational Therapy Association, Inc.

Lexical Retrieval of Nouns and Verbs in a Sentence Completion Task

ERIC Educational Resources Information Center

Abel, Alyson D.; Maguire, Mandy J.; Naqvi, Fizza M.; Kim, Angela Y.

2015-01-01

This study explored noun and verb retrieval using a sentence completion task to expand upon previous findings from picture naming tasks. Participants completed sentences missing either a target noun or verb in the final position. Non-target responses were coded for substitution type, imageability and frequency. Like picture naming, nouns and verbs…

An Agent-Based Simulation for Investigating the Impact of Stereotypes on Task-Oriented Group Formation

NASA Astrophysics Data System (ADS)

Maghami, Mahsa; Sukthankar, Gita

In this paper, we introduce an agent-based simulation for investigating the impact of social factors on the formation and evolution of task-oriented groups. Task-oriented groups are created explicitly to perform a task, and all members derive benefits from task completion. However, even in cases when all group members act in a way that is locally optimal for task completion, social forces that have mild effects on choice of associates can have a measurable impact on task completion performance. In this paper, we show how our simulation can be used to model the impact of stereotypes on group formation. In our simulation, stereotypes are based on observable features, learned from prior experience, and only affect an agent's link formation preferences. Even without assuming stereotypes affect the agents' willingness or ability to complete tasks, the long-term modifications that stereotypes have on the agents' social network impair the agents' ability to form groups with sufficient diversity of skills, as compared to agents who form links randomly. An interesting finding is that this effect holds even in cases where stereotype preference and skill existence are completely uncorrelated.

Precuing benefits for color and location in a visual search task.

PubMed

Vierck, Esther; Miller, Jeff

2008-02-01

Selection in multiple-item displays has been shown to benefit immensely from advance knowledge of target location (e.g., Henderson, 1991), leading to the suggestion that location is completely dominant in visual selective attention (e.g., Tsal & Lavie, 1993). Recently, direct selection by color has been reported in displays in which location does not vary (Vierck & Miller, 2005). The present experiment investigated the possibility of independent selection by color in a task with multiple-item displays and location precues in order to see whether color is also used for selection even when target location does vary and supposedly dominant location precues can be used. Precues provided independent information about the location and color of a target, and each type of precue could be either valid or invalid. The precues were followed by brief displays of six letters in six different colors, and participants had to discriminate the case of a prespecified target letter (e.g., R vs. r). Performance was much better when location cues were valid than when they were invalid, confirming the large advantage associated with valid advance location information. Performance was also better with valid advance color information, however, both when location cues were valid and when they were invalid. But these color benefits were dependent on the closeness of the colored letter to the cued location. Our results thus suggest that selection by color in a multiple-item display, where location and color information are independent from each other and equalized, is mediated by location information.

Method and Apparatus for Performance Optimization Through Physical Perturbation of Task Elements

NASA Technical Reports Server (NTRS)

Prinzel, Lawrence J., III (Inventor); Pope, Alan T. (Inventor); Palsson, Olafur S. (Inventor); Turner, Marsha J. (Inventor)

2016-01-01

The invention is an apparatus and method of biofeedback training for attaining a physiological state optimally consistent with the successful performance of a task, wherein the probability of successfully completing the task is made is inversely proportional to a physiological difference value, computed as the absolute value of the difference between at least one physiological signal optimally consistent with the successful performance of the task and at least one corresponding measured physiological signal of a trainee performing the task. The probability of successfully completing the task is made inversely proportional to the physiological difference value by making one or more measurable physical attributes of the environment in which the task is performed, and upon which completion of the task depends, vary in inverse proportion to the physiological difference value.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buchholz, Bruce A.

The project has two main goals: 1) Identify the types of adducts naphthalene (NA) forms with DNA and 2) determine whether adduct formation correlates with site selective tumor formation in defined subcompartments of the respiratory tract (respiratory and olfactory nasal epithelium and airways of mice, rats and rhesus monkeys). Five tasks are associated with the completion of the goals. Task 1: Contracting and Animal Use Approvals. IACUC and ACURO approvals are complete, The subcontract with UC Davis (UCD) was executed in December 2014. Task 2: Perform In Vitro Study for Goal 1. Rat samples exposed and in freezer while adductmore » standards are being made. Mouse samples need to be exposed in next quarter. Task 3: Perform In Vitro Study for Goal 2. Mouse ex vivo samples completed. Rat and monkey samples need to be completed in the next quarter. Task 4: Sample Preparation and Analysis. Mouse Goal 2 samples completed. Other samples remain to be done. Task 5: Data Interpretation and Reporting. Need rat data to write paper on adduct formation.« less

Correlates of individual, and age-related, differences in short-term learning.

PubMed

Zhang, Zhiyong; Davis, Hasker P; Salthouse, Timothy A; Tucker-Drob, Elliot M

2007-07-01

Latent growth models were applied to data on multitrial verbal and spatial learning tasks from two independent studies. Although significant individual differences in both initial level of performance and subsequent learning were found in both tasks, age differences were found only in mean initial level, and not in mean learning. In neither task was fluid or crystallized intelligence associated with learning. Although there were moderate correlations among the level parameters across the verbal and spatial tasks, the learning parameters were not significantly correlated with one another across task modalities. These results are inconsistent with the existence of a general (e.g., material-independent) learning ability.

Establishing the resting state default mode network derived from functional magnetic resonance imaging tasks as an endophenotype: A twins study.

PubMed

Korgaonkar, Mayuresh S; Ram, Kaushik; Williams, Leanne M; Gatt, Justine M; Grieve, Stuart M

2014-08-01

The resting state default mode network (DMN) has been shown to characterize a number of neurological and psychiatric disorders. Evidence suggests an underlying genetic basis for this network and hence could serve as potential endophenotype for these disorders. Heritability is a defining criterion for endophenotypes. The DMN is measured either using a resting-state functional magnetic resonance imaging (fMRI) scan or by extracting resting state activity from task-based fMRI. The current study is the first to evaluate heritability of this task-derived resting activity. 250 healthy adult twins (79 monozygotic and 46 dizygotic same sex twin pairs) completed five cognitive and emotion processing fMRI tasks. Resting state DMN functional connectivity was derived from these five fMRI tasks. We validated this approach by comparing connectivity estimates from task-derived resting activity for all five fMRI tasks, with those obtained using a dedicated task-free resting state scan in an independent cohort of 27 healthy individuals. Structural equation modeling using the classic twin design was used to estimate the genetic and environmental contributions to variance for the resting-state DMN functional connectivity. About 9-41% of the variance in functional connectivity between the DMN nodes was attributed to genetic contribution with the greatest heritability found for functional connectivity between the posterior cingulate and right inferior parietal nodes (P<0.001). Our data provide new evidence that functional connectivity measures from the intrinsic DMN derived from task-based fMRI datasets are under genetic control and have the potential to serve as endophenotypes for genetically predisposed psychiatric and neurological disorders. Copyright © 2014 Wiley Periodicals, Inc.

Assessment of unconstrained cerebrovascular reactivity marker for large age-range FMRI studies.

PubMed

Kannurpatti, Sridhar S; Motes, Michael A; Biswal, Bharat B; Rypma, Bart

2014-01-01

Breath hold (BH), a commonly used task to measure cerebrovascular reactivity (CVR) in fMRI studies varies in outcome among individuals due to subject-physiology and/or BH-inspiration/expiration differences (i.e., performance). In prior age-related fMRI studies, smaller task-related BOLD response variability is observed among younger than older individuals. Also, a linear CVR versus task relationship exists in younger individuals which maybe useful to test the accuracy of CVR responses in older groups. Hence we hypothesized that subject-related physiological and/or BH differences, if present, may compromise CVR versus task linearity in older individuals. To test the hypothesis, empirical BH versus task relationships from motor and cognitive areas were obtained in younger (mean age = 26 years) and older (mean age = 58 years) human subjects. BH versus task linearity was observed only in the younger group, confirming our hypothesis. Further analysis indicated BH responses and its variability to be similar in both younger and older groups, suggesting that BH may not accurately represent CVR in a large age range. Using the resting state fluctuation of amplitude (RSFA) as an unconstrained alternative to BH, subject-wise correspondence between BH and RSFA was tested. Correlation between BH versus RSFA was significant within the motor but was not significant in the cognitive areas in the younger and was completely disrupted in both areas in the older subjects indicating that BH responses are constrained by subject-related physiology and/or performance-related differences. Contrasting BH to task, RSFA-task relationships were independent of age accompanied by age-related increases in CVR variability as measured by RSFA, not observed with BH. Together the results obtained indicate that RSFA accurately represents CVR in any age range avoiding multiple and yet unknown physiologic and task-related pitfalls of BH.

Simultaneity, Sequentiality, and Speed: Organizational Messages about Multiple-Task Completion

ERIC Educational Resources Information Center

Stephens, Keri K.; Cho, Jaehee K.; Ballard, Dawna I.

2012-01-01

Workplace norms for task completion increasingly value speed and the ability to accomplish multiple tasks at once. This study situates this popularized issue of multitasking within the context of chronemics scholarship by addressing related issues of simultaneity, sequentiality, and speed. Ultimately, we consider 2 multiple-task completion…

A 24-Week Multi-Modality Exercise Program Improves Executive Control in Older Adults with a Self-Reported Cognitive Complaint: Evidence from the Antisaccade Task.

PubMed

Heath, Matthew; Shellington, Erin; Titheridge, Sam; Gill, Dawn P; Petrella, Robert J

2017-01-01

Exercise programs involving aerobic and resistance training (i.e., multiple-modality) have shown promise in improving cognition and executive control in older adults at risk, or experiencing, cognitive decline. It is, however, unclear whether cognitive training within a multiple-modality program elicits an additive benefit to executive/cognitive processes. This is an important question to resolve in order to identify optimal training programs that delay, or ameliorate, executive deficits in persons at risk for further cognitive decline. In the present study, individuals with a self-reported cognitive complaint (SCC) participated in a 24-week multiple-modality (i.e., the M2 group) exercise intervention program. In addition, a separate group of individuals with a SCC completed the same aerobic and resistance training as the M2 group but also completed a cognitive-based stepping task (i.e., multiple-modality, mind-motor intervention: M4 group). Notably, pre- and post-intervention executive control was examined via the antisaccade task (i.e., eye movement mirror-symmetrical to a target). Antisaccades are an ideal tool for the study of individuals with subtle executive deficits because of its hands- and language-free nature and because the task's neural mechanisms are linked to neuropathology in cognitive decline (i.e., prefrontal cortex). Results showed that M2 and M4 group antisaccade reaction times reliably decreased from pre- to post-intervention and the magnitude of the decrease was consistent across groups. Thus, multi-modality exercise training improved executive performance in persons with a SCC independent of mind-motor training. Accordingly, we propose that multiple-modality training provides a sufficient intervention to improve executive control in persons with a SCC.

Belief-bias reasoning in non-clinical delusion-prone individuals.

PubMed

Anandakumar, T; Connaughton, E; Coltheart, M; Langdon, R

2017-03-01

It has been proposed that people with delusions have difficulty inhibiting beliefs (i.e., "doxastic inhibition") so as to reason about them as if they might not be true. We used a continuity approach to test this proposal in non-clinical adults scoring high and low in psychometrically assessed delusion-proneness. High delusion-prone individuals were expected to show greater difficulty than low delusion-prone individuals on "conflict" items of a "belief-bias" reasoning task (i.e. when required to reason logically about statements that conflicted with reality), but not on "non-conflict" items. Twenty high delusion-prone and twenty low delusion-prone participants (according to the Peters et al. Delusions Inventory) completed a belief-bias reasoning task and tests of IQ, working memory and general inhibition (Excluded Letter Fluency, Stroop and Hayling Sentence Completion). High delusion-prone individuals showed greater difficulty than low delusion-prone individuals on the Stroop and Excluded Letter Fluency tests of inhibition, but no greater difficulty on the conflict versus non-conflict items of the belief-bias task. They did, however, make significantly more errors overall on the belief-bias task, despite controlling for IQ, working memory and general inhibitory control. The study had a relatively small sample size and used non-clinical participants to test a theory of cognitive processing in individuals with clinically diagnosed delusions. Results failed to support a role for doxastic inhibitory failure in non-clinical delusion-prone individuals. These individuals did, however, show difficulty with conditional reasoning about statements that may or may not conflict with reality, independent of any general cognitive or inhibitory deficits. Copyright © 2016 Elsevier Ltd. All rights reserved.

Belief-bias reasoning in non-clinical delusion-prone individuals.

PubMed

Anandakumar, T; Connaughton, E; Coltheart, M; Langdon, R

2017-09-01

It has been proposed that people with delusions have difficulty inhibiting beliefs (i.e., "doxastic inhibition") so as to reason about them as if they might not be true. We used a continuity approach to test this proposal in non-clinical adults scoring high and low in psychometrically assessed delusion-proneness. High delusion-prone individuals were expected to show greater difficulty than low delusion-prone individuals on "conflict" items of a "belief-bias" reasoning task (i.e. when required to reason logically about statements that conflicted with reality), but not on "non-conflict" items. Twenty high delusion-prone and twenty low delusion-prone participants (according to the Peters et al. Delusions Inventory) completed a belief-bias reasoning task and tests of IQ, working memory and general inhibition (Excluded Letter Fluency, Stroop and Hayling Sentence Completion). High delusion-prone individuals showed greater difficulty than low delusion-prone individuals on the Stroop and Excluded Letter Fluency tests of inhibition, but no greater difficulty on the conflict versus non-conflict items of the belief-bias task. They did, however, make significantly more errors overall on the belief-bias task, despite controlling for IQ, working memory and general inhibitory control. The study had a relatively small sample size and used non-clinical participants to test a theory of cognitive processing in individuals with clinically diagnosed delusions. Results failed to support a role for doxastic inhibitory failure in non-clinical delusion-prone individuals. These individuals did, however, show difficulty with conditional reasoning about statements that may or may not conflict with reality, independent of any general cognitive or inhibitory deficits. Copyright © 2016 Elsevier Ltd. All rights reserved.

Design, engineering and evaluation of refractory liners for slagging gasifiers. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

deTineo, B J; Booth, G; Firestone, R F

1982-08-01

The contract for this program was awarded at the end of September 1978. Work was started on 1 October 1978, on Tasks A, B, and E. Task A, Conceptual Liner Designs, and Task B, Test System Design and Construction, were completed. Task C, Liner Tests, and Task D, Liner Design Evaluation, were to begin upon completion of Task B. Task E, Liner Model Development, is inactive after an initial data compilation and theoretical model development effort. It was to be activated as soon as data were available from Task D. Task F, Liner Design Handbook, was active along with Taskmore » A since the reports of both tasks were to use the same format. At this time, Tasks C, D, and F are not to be completed since funding of this project was phased out by DOE directive. The refractory text facility, which was constructed, was tested and found to perform satisfactorily. It is described in detail, including a hazard analysis which was performed. (LTN)« less

Muscle Feasibility for Cosmos Rhesus

NASA Technical Reports Server (NTRS)

Edgerton, V. Reggie (Principal Investigator); Roland, Roy R.; Hodgson, John A.

1994-01-01

The following tasks were proposed for the Cosmos project: 1) Complete recordings of all preflight candidates during performance of a foot pedal motor control task while in the space capsule mock-up. 2) Complete recordings of all preflight candidates during locomotion and postural tasks. 3) Complete recordings of 24-hour spontaneous cage activity in the two flight monkeys before and after flight and of at least three control (non-flight) monkeys after the flight has been completed. 4) Complete recordings of the foot pedal and motor control tasks during flight and postflight as scheduled. 5) Complete recordings of the vertical drop test pre, during and postflight for the two flight and three control monkeys. 6) Complete recordings of locomotion and posture tests of the two flight monkeys postflight. 7) Complete recordings of locomotion and postural tests of at least three control (non-flight) monkeys during the postflight period. 8) Recalibrate buckles of the two flight and of at least three control monkeys postflight. 9) Complete analysis of the 24 hour EMG recordings of all monkeys. 10) Complete analysis of the foot pedal, locomotor and postural motor control tasks for the two flight and three control monkeys. It was proposed that efforts in the first postflight year be concentrated on the two flight animals and three postflight animals.

Naturalistic Assessment of Executive Function and Everyday Multitasking in Healthy Older Adults

PubMed Central

McAlister, Courtney; Schmitter-Edgecombe, Maureen

2013-01-01

Everyday multitasking and its cognitive correlates were investigated in an older adult population using a naturalistic task, the Day Out Task. Fifty older adults and 50 younger adults prioritized, organized, initiated and completed a number of subtasks in a campus apartment to prepare for a day out (e.g., gather ingredients for a recipe, collect change for a bus ride). Participants also completed tests assessing cognitive constructs important in multitasking. Compared to younger adults, the older adults took longer to complete the everyday tasks and more poorly sequenced the subtasks. Although they initiated, completed, and interweaved a similar number of subtasks, the older adults demonstrated poorer task quality and accuracy, completing more subtasks inefficiently. For the older adults, reduced prospective memory abilities were predictive of poorer task sequencing, while executive processes and prospective memory were predictive of inefficiently completed subtasks. The findings suggest that executive dysfunction and prospective memory difficulties may contribute to the age-related decline of everyday multitasking abilities in healthy older adults. PMID:23557096

Behavioral and Neural Correlates of Executive Function: Interplay between Inhibition and Updating Processes.

PubMed

Kim, Na Young; Wittenberg, Ellen; Nam, Chang S

2017-01-01

This study investigated the interaction between two executive function processes, inhibition and updating, through analyses of behavioral, neurophysiological, and effective connectivity metrics. Although, many studies have focused on behavioral effects of executive function processes individually, few studies have examined the dynamic causal interactions between these two functions. A total of twenty participants from a local university performed a dual task combing flanker and n-back experimental paradigms, and completed the Operation Span Task designed to measure working memory capacity. We found that both behavioral (accuracy and reaction time) and neurophysiological (P300 amplitude and alpha band power) metrics on the inhibition task (i.e., flanker task) were influenced by the updating load (n-back level) and modulated by working memory capacity. Using independent component analysis, source localization (DIPFIT), and Granger Causality analysis of the EEG time-series data, the present study demonstrated that manipulation of cognitive demand in a dual executive function task influenced the causal neural network. We compared connectivity across three updating loads (n-back levels) and found that experimental manipulation of working memory load enhanced causal connectivity of a large-scale neurocognitive network. This network contains the prefrontal and parietal cortices, which are associated with inhibition and updating executive function processes. This study has potential applications in human performance modeling and assessment of mental workload, such as the design of training materials and interfaces for those performing complex multitasking under stress.

The effects of military body armour on trunk and hip kinematics during performance of manual handling tasks (.).

PubMed

Lenton, Gavin; Aisbett, Brad; Neesham-Smith, Daniel; Carvajal, Alvaro; Netto, Kevin

2016-06-01

Musculoskeletal injuries are reported as burdening the military. An identified risk factor for injury is carrying heavy loads; however, soldiers are also required to wear their load as body armour. To investigate the effects of body armour on trunk and hip kinematics during military-specific manual handling tasks, 16 males completed 3 tasks while wearing each of 4 body armour conditions plus a control. Three-dimensional motion analysis captured and quantified all kinematic data. Average trunk flexion for the weightiest armour type was higher compared with control during the carry component of the ammunition box lift (p < 0.001) and sandbag lift tasks (p < 0.001). Trunk rotation ROM was lower for all armour types compared with control during the ammunition box place component (p < 0.001). The altered kinematics with body armour occurred independent of armour design. In order to optimise armour design, manufacturers need to work with end-users to explore how armour configurations interact with range of personal and situational factors in operationally relevant environments. Practitioner Summary: Musculoskeletal injuries are reported as burdening the military and may relate to body armour wear. Body armour increased trunk flexion and reduced trunk rotation during military-specific lifting and carrying tasks. The altered kinematics may contribute to injury risk, but more research is required.

The singer's voice range profile: female professional opera soloists.

PubMed

Lamarche, Anick; Ternström, Sten; Pabon, Peter

2010-07-01

This work concerns the collection of 30 voice range profiles (VRPs) of female operatic voice. We address the questions: Is there a need for a singer's protocol in VRP acquisition? Are physiological measurements sufficient or should the measurement of performance capabilities also be included? Can we address the female singing voice in general or is there a case for categorizing voices when studying phonetographic data? Subjects performed a series of structured tasks involving both standard speech voice protocols and additional singing tasks. Singers also completed an extensive questionnaire. Physiological VRPs differ from performance VRPs. Two new VRP metrics, the voice area above a defined level threshold and the dynamic range independent from the fundamental frequency (F(0)), were found to be useful in the analysis of singer VRPs. Task design had no effect on performance VRP outcomes. Voice category differences were mainly attributable to phonation frequency-based information. Results support the clinical importance of addressing the vocal instrument as it is used in performance. Equally important is the elaboration of a protocol suitable for the singing voice. The given context and instructions can be more important than task design for performance VRPs. Yet, for physiological VRP recordings, task design remains critical. Both types of VRPs are suggested for a singer's voice evaluation. Copyright (c) 2010 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

The ties to unbind: age-related differences in feature (un)binding in working memory for emotional faces

PubMed Central

Pehlivanoglu, Didem; Jain, Shivangi; Ariel, Robert; Verhaeghen, Paul

2014-01-01

In the present study, we investigated age-related differences in the processing of emotional stimuli. Specifically, we were interested in whether older adults would show deficits in unbinding emotional expression (i.e., either no emotion, happiness, anger, or disgust) from bound stimuli (i.e., photographs of faces expressing these emotions), as a hyper-binding account of age-related differences in working memory would predict. Younger and older adults completed different N-Back tasks (side-by-side 0-Back, 1-Back, 2-Back) under three conditions: match/mismatch judgments based on either the identity of the face (identity condition), the face’s emotional expression (expression condition), or both identity and expression of the face (both condition). The two age groups performed more slowly and with lower accuracy in the expression condition than in the both condition, indicating the presence of an unbinding process. This unbinding effect was more pronounced in older adults than in younger adults, but only in the 2-Back task. Thus, older adults seemed to have a specific deficit in unbinding in working memory. Additionally, no age-related differences were found in accuracy in the 0-Back task, but such differences emerged in the 1-Back task, and were further magnified in the 2-Back task, indicating independent age-related differences in attention/STM and working memory. Pupil dilation data confirmed that the attention/STM version of the task (1-Back) is more effortful for older adults than younger adults. PMID:24795660

The ties to unbind: age-related differences in feature (un)binding in working memory for emotional faces.

PubMed

Pehlivanoglu, Didem; Jain, Shivangi; Ariel, Robert; Verhaeghen, Paul

2014-01-01

In the present study, we investigated age-related differences in the processing of emotional stimuli. Specifically, we were interested in whether older adults would show deficits in unbinding emotional expression (i.e., either no emotion, happiness, anger, or disgust) from bound stimuli (i.e., photographs of faces expressing these emotions), as a hyper-binding account of age-related differences in working memory would predict. Younger and older adults completed different N-Back tasks (side-by-side 0-Back, 1-Back, 2-Back) under three conditions: match/mismatch judgments based on either the identity of the face (identity condition), the face's emotional expression (expression condition), or both identity and expression of the face (both condition). The two age groups performed more slowly and with lower accuracy in the expression condition than in the both condition, indicating the presence of an unbinding process. This unbinding effect was more pronounced in older adults than in younger adults, but only in the 2-Back task. Thus, older adults seemed to have a specific deficit in unbinding in working memory. Additionally, no age-related differences were found in accuracy in the 0-Back task, but such differences emerged in the 1-Back task, and were further magnified in the 2-Back task, indicating independent age-related differences in attention/STM and working memory. Pupil dilation data confirmed that the attention/STM version of the task (1-Back) is more effortful for older adults than younger adults.

Pressure to cooperate: is positive reward interdependence really needed in cooperative learning?

PubMed

Buchs, Céline; Gilles, Ingrid; Dutrévis, Marion; Butera, Fabrizio

2011-03-01

BACKGROUND. Despite extensive research on cooperative learning, the debate regarding whether or not its effectiveness depends on positive reward interdependence has not yet found clear evidence. AIMS. We tested the hypothesis that positive reward interdependence, as compared to reward independence, enhances cooperative learning only if learners work on a 'routine task'; if the learners work on a 'true group task', positive reward interdependence induces the same level of learning as reward independence. SAMPLE. The study involved 62 psychology students during regular workshops. METHOD. Students worked on two psychology texts in cooperative dyads for three sessions. The type of task was manipulated through resource interdependence: students worked on either identical (routine task) or complementary (true group task) information. Students expected to be assessed with a Multiple Choice Test (MCT) on the two texts. The MCT assessment type was introduced according to two reward interdependence conditions, either individual (reward independence) or common (positive reward interdependence). A follow-up individual test took place 4 weeks after the third session of dyadic work to examine individual learning. RESULTS. The predicted interaction between the two types of interdependence was significant, indicating that students learned more with positive reward interdependence than with reward independence when they worked on identical information (routine task), whereas students who worked on complementary information (group task) learned the same with or without reward interdependence. CONCLUSIONS. This experiment sheds light on the conditions under which positive reward interdependence enhances cooperative learning, and suggests that creating a real group task allows to avoid the need for positive reward interdependence. © 2010 The British Psychological Society.

Upper limb motor function in young adults with spina bifida and hydrocephalus

PubMed Central

Salman, M. S.; Jewell, D.; Hetherington, R.; Spiegler, B. J.; MacGregor, D. L.; Drake, J. M.; Humphreys, R. P.; Gentili, F.

2011-01-01

Objective The objective of the study was to measure upper limb motor function in young adults with spina bifida meningomyelocele (SBM) and typically developing age peers. Method Participants were 26 young adults with SBM, with a Verbal or Performance IQ score of at least 70 on the Wechsler scales, and 27 age- and gender-matched controls. Four upper limb motor function tasks were performed under four different visual and cognitive challenge conditions. Motor independence was assessed by questionnaire. Results Fewer SBM than control participants obtained perfect posture and rebound scores. The SBM group performed less accurately and was more disrupted by cognitive challenge than controls on limb dysmetria tasks. The SBM group was slower than controls on the diadochokinesis task. Adaptive motor independence was related to one upper limb motor task, arm posture, and upper rather than lower spinal lesions were associated with less motor independence. Conclusions Young adults with SBM have significant limitations in upper limb function and are more disrupted by some challenges while performing upper limb motor tasks. Within the group of young adults with SBM, upper spinal lesions compromise motor independence more than lower spinal lesions. PMID:19672605

The Independence and Interdependence of Coacting Observers in Regard to Performance Efficiency, Workload, and Stress in a Vigilance Task

DTIC Science & Technology

2016-09-01

independence/ dependence , evaluation apprehension, workload, stress 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT: SAR 18. NUMBER...indepen- dence/ dependence , evaluation apprehension, workload, stress IntroductIon Vigilance or sustained attention tasks require observers to maintain

Dissociating word stem completion and cued recall as a function of divided attention at retrieval.

PubMed

Clarke, A J Benjamin; Butler, Laurie T

2008-10-01

The aim of this study was to investigate the widely held, but largely untested, view that implicit memory (repetition priming) reflects an automatic form of retrieval. Specifically, in Experiment 1 we explored whether a secondary task (syllable monitoring), performed during retrieval, would disrupt performance on explicit (cued recall) and implicit (stem completion) memory tasks equally. Surprisingly, despite substantial memory and secondary costs to cued recall when performed with a syllable-monitoring task, the same manipulation had no effect on stem completion priming or on secondary task performance. In Experiment 2 we demonstrated that even when using a particularly demanding version of the stem completion task that incurred secondary task costs, the corresponding disruption to implicit memory performance was minimal. Collectively, the results are consistent with the view that implicit memory retrieval requires little or no processing capacity and is not seemingly susceptible to the effects of dividing attention at retrieval.

Completeness and overlap in open access systems: Search engines, aggregate institutional repositories and physics-related open sources.

PubMed

Tsay, Ming-Yueh; Wu, Tai-Luan; Tseng, Ling-Li

2017-01-01

This study examines the completeness and overlap of coverage in physics of six open access scholarly communication systems, including two search engines (Google Scholar and Microsoft Academic), two aggregate institutional repositories (OAIster and OpenDOAR), and two physics-related open sources (arXiv.org and Astrophysics Data System). The 2001-2013 Nobel Laureates in Physics served as the sample. Bibliographic records of their publications were retrieved and downloaded from each system, and a computer program was developed to perform the analytical tasks of sorting, comparison, elimination, aggregation and statistical calculations. Quantitative analyses and cross-referencing were performed to determine the completeness and overlap of the system coverage of the six open access systems. The results may enable scholars to select an appropriate open access system as an efficient scholarly communication channel, and academic institutions may build institutional repositories or independently create citation index systems in the future. Suggestions on indicators and tools for academic assessment are presented based on the comprehensiveness assessment of each system.

Establishment of performance standards and a cut-score for the Canadian Forces firefighter physical fitness maintenance evaluation (FF PFME).

PubMed

Todd Rogers, W; Docherty, David; Petersen, Stewart

2014-01-01

The bookmark method for setting cut-scores was used to re-set the cut-score for the Canadian Forces Firefighter Physical Fitness Maintenance Evaluation (FF PFME). The time required to complete 10 tasks that together simulate a first-response firefighting emergency was accepted as a measure of work capacity. A panel of 25 Canadian Forces firefighter supervisors set cut-scores in three rounds. Each round involved independent evaluation of nine video work samples, where the times systematically increased from 400 seconds to 560 seconds. Results for Round 1 were discussed before moving to Round 2 and results for Round 2 were discussed before moving to Round 3. Accounting for the variability among panel members at the end of Round 3, a cut-score of 481 seconds (mean Round 3 plus 2 SEM) was recommended. Firefighters who complete the FF PFME in 481 seconds or less have the physical capacity to complete first-response firefighting work.

Step-Count Accuracy of 3 Motion Sensors for Older and Frail Medical Inpatients.

PubMed

McCullagh, Ruth; Dillon, Christina; O'Connell, Ann Marie; Horgan, N Frances; Timmons, Suzanne

2017-02-01

To measure the step-count accuracy of an ankle-worn accelerometer, a thigh-worn accelerometer, and a pedometer in older and frail inpatients. Cross-sectional design study. Research room within a hospital. Convenience sample of inpatients (N=32; age, ≥65 years) who were able to walk 20m independently with or without a walking aid. Patients completed a 40-minute program of predetermined tasks while wearing the 3 motion sensors simultaneously. Video recording of the procedure provided the criterion measurement of step count. Mean percentage errors were calculated for all tasks, for slow versus fast walkers, for independent walkers versus walking-aid users, and over shorter versus longer distances. The intraclass correlation was calculated, and accuracy was graphically displayed by Bland-Altman plots. Thirty-two patients (mean age, 78.1±7.8y) completed the study. Fifteen (47%) were women, and 17 (51%) used walking aids. Their median speed was .46m/s (interquartile range [IQR], .36-.66m/s). The ankle-worn accelerometer overestimated steps (median error, 1% [IQR, -3% to 13%]). The other motion sensors underestimated steps (median error, 40% [IQR, -51% to -35%] and 38% [IQR -93% to -27%], respectively). The ankle-worn accelerometer proved to be more accurate over longer distances (median error, 3% [IQR, 0%-9%]) than over shorter distances (median error, 10% [IQR, -23% to 9%]). The ankle-worn accelerometer gave the most accurate step-count measurement and was most accurate over longer distances. Neither of the other motion sensors had acceptable margins of error. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Research on Intelligent Interface in Double-front Work Machines

NASA Astrophysics Data System (ADS)

Kamezaki, Mitsuhiro; Iwata, Hiroyasu; Sugano, Shigeki

This paper proposes a work state identification method with full independent of work environmental conditions and operator skill levels for construction machinery. Advanced operated-work machines, which have been designed for complicated tasks, require intelligent systems that can provide the quantitative work analysis needed to determine effective work procedures and that can provide operational and cognitive support for operators. Construction work environments are extremely complicated, however, and this makes state identification, which is a key technology for an intelligent system, difficult. We therefore defined primitive static states (PSS) that are determined using on-off information for the lever inputs and manipulator loads for each part of the grapple and front and that are completely independent of the various environmental conditions and variation in operator skill level that can cause an incorrect work state identification. To confirm the usefulness of PSS, we performed experiments with a demolition task by using our virtual reality simulator. We confirmed that PSS could robustly and accurately identify the work states and that untrained skills could be easily inferred from the results of PSS-based work analysis. We also confirmed in skill-training experiments that advice information based on PSS-based skill analysis greatly improved operator's work performance. We thus confirmed that PSS can adequately identify work states and are useful for work analysis and skill improvement.

When anger dominates the mind: Increased motor corticospinal excitability in the face of threat

PubMed Central

Hortensius, Ruud

2016-01-01

Abstract Threat demands fast and adaptive reactions that are manifested at the physiological, behavioral, and phenomenological level and are responsive to the direction of threat and its severity for the individual. Here, we investigated the effects of threat directed toward or away from the observer on motor corticospinal excitability and explicit recognition. Sixteen healthy right‐handed volunteers completed a transcranial magnetic stimulation (TMS) task and a separate three‐alternative forced‐choice emotion recognition task. Single‐pulse TMS to the left primary motor cortex was applied to measure motor evoked potentials from the right abductor pollicis brevis in response to dynamic angry, fearful, and neutral bodily expressions with blurred faces directed toward or away from the observer. Results showed that motor corticospinal excitability increased independent of direction of anger compared with fear and neutral. In contrast, anger was better recognized when directed toward the observer compared with when directed away from the observer, while the opposite pattern was found for fear. The present results provide evidence for the differential effects of threat direction on explicit recognition and motor corticospinal excitability. In the face of threat, motor corticospinal excitability increases independently of the direction of anger, indicative of the importance of more automatic reactions to threat. PMID:27325519

Surface Electromyographic Activity of the Upper Trapezius Before and After a Single Dry Needling Session in Female Office Workers With Trapezius Myalgia.

PubMed

De Meulemeester, Kayleigh; Calders, Patrick; Dewitte, Vincent; Barbe, Tom; Danneels, Lieven; Cagnie, Barbara

2017-12-01

Myofascial pain can be accompanied by a disturbed surface electromyographic (sEMG) activity. Nevertheless, the effect of myofascial treatment techniques, such as dry needling (DN), on the sEMG activity is poorly investigated. Several DN studies also emphasize the importance of eliciting local twitch responses (LTRs) during treatment. However, studies investigating the added value of LTRs are scarce. Therefore, the aims of this study were first to evaluate the effect of DN on the sEMG activity of myalgic muscle tissue, compared with no intervention (rest), and secondly to identify whether this effect is dependent of eliciting LTRs during DN. Twenty-four female office workers with work-related trapezius myalgia were included. After completion of a typing task, changes in sEMG activity were evaluated after a DN treatment of the upper trapezius, compared with rest. The sEMG activity increased after rest and after DN, but this increase was significantly smaller 10 minutes after DN, compared with rest. These differences were independent whether LTRs were elicited or not. Dry needling leads to a significantly lower increase in sEMG activity of the upper trapezius, compared with no intervention, after a typing task. This difference was independent of eliciting LTRs.

The spatial mismatch effect is based on global configuration and not on perceptual records within the visual cache.

PubMed

Zimmer, Hubert D; Lehnert, Günther

2006-01-01

If configurations of objects are presented in a S1-S2 matching task for the identity of objects a spatial mismatch effect occurs. Changing the (irrelevant) spatial layout lengthens response times. We investigated what causes this effect. We observed a reliable mismatch effect that was not influenced by a secondary task during maintenance. Neither articulatory suppression (Experiment 1), nor unattended (Experiments 2 and 6) or attended visual material (Experiment 3) reduced the effect, and this was independent of the length of the retention interval (Experiment 6). The effect was also rather independent of the visual appearance of the local elements. It was of similar size with color patches (Experiment 4) and with completely different surface information when testing was cross modal (Experiment 5), and the name-ability of the global configuration was not relevant (Experiments 6 and 7). In contrast, the figurative similarity of the configurations of S1 and S2 systematically influenced the size of the spatial mismatch effect (Experiment 7). We conclude that the spatial mismatch effect is caused by a mismatch of the global shape of the configuration stored together with the objects of S1 and not by a mismatch of templates of perceptual records maintained in a visual cache.

Analysis of film cooling in rocket nozzles

NASA Technical Reports Server (NTRS)

Woodbury, Keith A.

1993-01-01

This report summarizes the findings on the NASA contract NAG8-212, Task No. 3. The overall project consists of three tasks, all of which have been successfully completed. In addition, some supporting supplemental work, not required by the contract, has been performed and is documented herein. Task 1 involved the modification of the wall functions in the code FDNS (Finite Difference Navier-Stokes) to use a Reynolds Analogy-based method. This task was completed in August, 1992. Task 2 involved the verification of the code against experimentally available data. The data chosen for comparison was from an experiment involving the injection of helium from a wall jet. Results obtained in completing this task also show the sensitivity of the FDNS code to unknown conditions at the injection slot. This task was completed in September, 1992. Task 3 required the computation of the flow of hot exhaust gases through the P&W 40K subscale nozzle. Computations were performed both with and without film coolant injection. This task was completed in July, 1993. The FDNS program tends to overpredict heat fluxes, but, with suitable modeling of backside cooling, may give reasonable wall temperature predictions. For film cooling in the P&W 40K calorimeter subscale nozzle, the average wall temperature is reduced from 1750R to about 1050R by the film cooling. The average wall heat flux is reduced by a factor of 3.

Variable and Asymmetric Range of Enslaving: Fingers Can Act Independently over Small Range of Flexion

PubMed Central

van den Noort, Josien C.; van Beek, Nathalie; van der Kraan, Thomas; Veeger, DirkJan H. E. J.; Stegeman, Dick F.; Veltink, Peter H.; Maas, Huub

2016-01-01

The variability in the numerous tasks in which we use our hands is very large. However, independent movement control of individual fingers is limited. To assess the extent of finger independency during full-range finger flexion including all finger joints, we studied enslaving (movement in non-instructed fingers) and range of independent finger movement through the whole finger flexion trajectory in single and multi-finger movement tasks. Thirteen young healthy subjects performed single- and multi-finger movement tasks under two conditions: active flexion through the full range of movement with all fingers free to move and active flexion while the non-instructed finger(s) were restrained. Finger kinematics were measured using inertial sensors (PowerGlove), to assess enslaving and range of independent finger movement. Although all fingers showed enslaving movement to some extent, highest enslaving was found in adjacent fingers. Enslaving effects in ring and little finger were increased with movement of additional, non-adjacent fingers. The middle finger was the only finger affected by restriction in movement of non-instructed fingers. Each finger showed a range of independent movement before the non-instructed fingers started to move, which was largest for the index finger. The start of enslaving was asymmetrical for adjacent fingers. Little finger enslaving movement was affected by multi-finger movement. We conclude that no finger can move independently through the full range of finger flexion, although some degree of full independence is present for smaller movements. This range of independent movement is asymmetric and variable between fingers and between subjects. The presented results provide insight into the role of finger independency for different types of tasks and populations. PMID:27992598

Visual cue-specific craving is diminished in stressed smokers.

PubMed

Cochran, Justinn R; Consedine, Nathan S; Lee, John M J; Pandit, Chinmay; Sollers, John J; Kydd, Robert R

2017-09-01

Craving among smokers is increased by stress and exposure to smoking-related visual cues. However, few experimental studies have tested both elicitors concurrently and considered how exposures may interact to influence craving. The current study examined craving in response to stress and visual cue exposure, separately and in succession, in order to better understand the relationship between craving elicitation and the elicitor. Thirty-nine smokers (21 males) who forwent smoking for 30 minutes were randomized to complete a stress task and a visual cue task in counterbalanced orders (creating the experimental groups); for the cue task, counterbalanced blocks of neutral, motivational control, and smoking images were presented. Self-reported craving was assessed after each block of visual stimuli and stress task, and after a recovery period following each task. As expected, the stress and smoking images generated greater craving than neutral or motivational control images (p < .001). Interactions indicated craving in those who completed the stress task first differed from those who completed the visual cues task first (p < .05), such that stress task craving was greater than all image type craving (all p's < .05) only if the visual cue task was completed first. Conversely, craving was stable across image types when the stress task was completed first. Findings indicate when smokers are stressed, visual cues have little additive effect on craving, and different types of visual cues elicit comparable craving. These findings may imply that once stressed, smokers will crave cigarettes comparably notwithstanding whether they are exposed to smoking image cues.

Associations Between Physical Fitness Indices and Working Memory in Breast Cancer Survivors and Age-Matched Controls

PubMed Central

Mackenzie, Michael J.; Zuniga, Krystle E.; Raine, Lauren B.; Awick, Elizabeth A.; Hillman, Charles H.; Kramer, Arthur F.

2016-01-01

Abstract Background: This study examined the effects of cardiorespiratory fitness, heart rate recovery, and physical activity on working memory in breast cancer survivors and age-matched controls. Method: Using a case-control design, 32 women who had received a breast cancer diagnosis and completed primary treatment within the past 36-months (11 radiation only; 21 chemotherapy) and 30 age-matched women with no previous cancer diagnosis completed a n-back continuous performance task commonly used as an assessment of working memory. In addition, cardiorespiratory fitness and heart rate recovery were measured during a submaximal graded exercise test and physical activity was measured using 7-days of accelerometer monitoring. Results: Breast cancer survivors who had received chemotherapy had poorer heart rate recovery (p = .010) and engaged in less physical activity than women who had received radiation only (p = .004) or non-cancer controls (p = .029). Cancer treatment (radiation; chemotherapy) predicted differences in reaction times on the 1-back working memory task (p = .029). However, more rapid heart rate recovery predicted shorter reaction times on the 1-back task in the age-matched control group (p = .002). All participants with greater cardiorespiratory fitness displayed greater accuracy independent of disease status on the 1-back task (p = .017). No significant group differences in reaction times were observed for 2-back target trials between breast cancer survivors and controls. However, greater total physical activity predicted shorter reaction times in breast cancer survivors (radiation, chemotherapy) on the 2-back task (p = .014). In addition, all participants who exhibited more rapid heart rate recovery demonstrated better greater accuracy regardless of disease status (p = .013). Conclusion: These findings support differences in physical activty participation, heart rate recovery, and 1- and 2-back working memory reaction times between breast cancer survivors and age-matched controls. Greater cardiorespiratory fitness, heart rate recovery, and physical activity were positively associated with better working memory performance across conditions. PMID:26418463

Face, content and concurrent validity of the Mimic® dV-Trainer for robot-assisted endoscopic surgery: a prospective study.

PubMed

Egi, H; Hattori, M; Tokunaga, M; Suzuki, T; Kawaguchi, K; Sawada, H; Ohdan, H

2013-01-01

The aim of this study was to determine whether any correlation exists between the performance of the Mimic® dV-Trainer (Mimic Technologies, Seattle, Wash., USA) and the da Vinci Surgical System (Intuitive Surgical, Sunnyvale, Calif., USA). Twelve participants were recruited, ranging from residents to consultants. We used four training tasks, consisting of 'Pick and Place', 'Peg Board', 'Thread the Rings' and 'Suture Sponge', from the software program of the Mimic dV-Trainer. The performance of the participants was recorded and measured. Additionally, we prepared the same tasks for the da Vinci Surgical System. All participants completed the tasks using the da Vinci Surgical System and were assessed according to time, the Objective Structured Assessment of Technical Skill checklist and the global rating score for endoscopic suturing assessed by two independent blinded observers. After performing these tasks, the participants completed a questionnaire that evaluated the Mimic dV-Trainer's face and content validity. The final results for each participant for the Mimic dV-Trainer and the da Vinci Surgical System were compared. All participants ranked the Mimic dV-Trainer as a realistic training platform that is useful for residency training. There was a significant relationship between the Mimic dV-Trainer and the da Vinci Surgical System in all four tasks. We verified the reliability of the assessment of the checklist and the global rating scores for endoscopic suturing assessed by the two blinded observers using Cronbach's alpha test (r = 0.803, 0.891). We evaluated the concurrent validity of the Mimic dV-Trainer and the da Vinci Surgical System. Our results suggest the possibility that training using the Mimic dV-Trainer may therefore be able to improve the operator's performance during live robot-assisted surgery. © 2013 S. Karger AG, Basel.

Report by the International Space Station (ISS) Management and Cost Evaluation (IMCE) Task Force

NASA Technical Reports Server (NTRS)

Young, A. Thomas; Kellogg, Yvonne (Technical Monitor)

2001-01-01

The International Space Station (ISS) Management and Cost Evaluation Task Force (IMCE) was chartered to conduct an independent external review and assessment of the ISS cost, budget, and management. In addition, the Task Force was asked to provide recommendations that could provide maximum benefit to the U.S. taxpayers and the International Partners within the President's budget request. The Task Force has made the following principal findings: (1) The ISS Program's technical achievements to date, as represented by on-orbit capability, are extraordinary; (2) The Existing ISS Program Plan for executing the FY 02-06 budget is not credible; (3) The existing deficiencies in management structure, institutional culture, cost estimating, and program control must be acknowledged and corrected for the Program to move forward in a credible fashion; (4) Additional budget flexibility, from within the Office of Space Flight (OSF) must be provided for a credible core complete program; (5) The research support program is proceeding assuming the budget that was in place before the FY02 budget runout reduction of $1B; (6) There are opportunities to maximize research on the core station program with modest cost impact; (7) The U.S. Core Complete configuration (three person crew) as an end-state will not achieve the unique research potential of the ISS; (8) The cost estimates for the U.S.-funded enhancement options (e.g., permanent seven person crew) are not sufficiently developed to assess credibility. After these findings, the Task Force has formulated several primary recommendations which are published here and include: (1) Major changes must be made in how the ISS program is managed; (2) Additional cost reductions are required within the baseline program; (3) Additional funds must be identified and applied from the Human Space Flight budget; (4) A clearly defined program with a credible end-state, agreed to by all stakeholders, must be developed and implemented.

Dr. Lenke Horvath (1917-1991): Creator of Pediatric Neurosurgery in Romania.

PubMed

Mohan, Dumitru; Moisa, Horatiu Alexandru; Nica, Dan Aurel; Ciurea, Alexandru Vlad

2016-04-01

The development of neurosurgery as an independent specialty took place with great difficulty in Romania. In this respect, the most revered personalities are those of Professor Alexandru Moruzzi (1900-1957) (in Iasi) and Professor Dimitrie Bagdasar (1893-1946) (in Bucharest), who are the fathers of modern neurosurgery in Romania. Professor Bagdasar was schooled in Professor Harvey Cushing's clinic in Boston and is credited with creating the first completely independent neurosurgical unit in Romania. His legacy was carried on with honor by Professor Constantin Arseni (1912-1994), who, in 1975, tasked Dr. Lenke Horvath (1917-1991) with creating the first autonomous pediatric neurosurgery unit in Bucharest. This article is a small tribute to the founder of pediatric neurosurgery in Romania and one of the female pioneer neurosurgeons, who, by personal example of dedication and hard work, radically changed medical thinking and neurosurgery in Romania. Copyright © 2016 Elsevier Inc. All rights reserved.

The recall of information from working memory. Insights from behavioural and chronometric perspectives.

PubMed

Towse, John N; Cowan, Nelson; Hitch, Graham J; Horton, Neil J

2008-01-01

We describe and evaluate a recall reconstruction hypothesis for working memory (WM), according to which items can be recovered from multiple memory representations. Across four experiments, participants recalled memoranda that were either integrated with or independent of the sentence content. We found consistently longer pauses accompanying the correct recall of integrated compared with independent words, supporting the argument that sentence memory could scaffold the access of target items. Integrated words were also more likely to be recalled correctly, dependent on the details of the task. Experiment 1 investigated the chronometry of spoken recall for word span and reading span, with participants completing an unfinished sentence in the latter case. Experiments 2 and 3 confirm recall time differences without using word generation requirements, while Experiment 4 used an item and order response choice paradigm with nonspoken responses. Data emphasise the value of recall timing in constraining theories of WM functioning.

Depressive symptoms and poorer performance on the Stroop Task are associated with weight gain.

PubMed

Stinson, Emma J; Krakoff, Jonathan; Gluck, Marci E

2018-03-15

Executive function impairments and depression are associated with obesity but whether they predict weight gain is unclear. Forty-six individuals (35m, 37±10y) completed the Stroop Task, Iowa Gambling Task (IGT), Wisconsin Card Sorting Task (WCST), Inventory for Depressive Symptomatology (IDS-SR), Physical Anhedonia Scale (PAS), and Perceived Stress Scale (PSS). Body composition (DXA) and fasting glucose were also measured. Data from return visits were used to assess changes in weight. Poorer Stroop and WCST performance associated with higher BMI whereas poorer IGT and WCST performance associated with higher body fat (%; all p's≤0.05). Stroop interference (p=0.04; p=0.05) and IDS-SR (p=0.06; p=0.02) associated with increased BMI and weight gain (%/yr). In a multivariate linear model Stroop interference (β=0.40, p<0.01; β=0.35, p<0.01) and IDS-SR (β=0.38, p<0.01; β=0.37, p<0.01) independently predicted increased BMI and weight gain (%/yr) even after controlling for baseline weight and glucose levels. Poorer response inhibition and depressive symptoms, but not glucose levels, predicted weight gain. Evaluating neurocognitive and mood deficits could improve current treatment strategies for weight loss. Clinical Trial Registration Numbers NCT00523627, NCT00342732, NCT01224704. clinicaltrials.gov. Published by Elsevier Inc.

Joint Simon effects in extrapersonal space.

PubMed

Welsh, Timothy N; Kiernan, Dovin; Neyedli, Heather F; Ray, Matthew; Pratt, Jay; Potruff, Andrew; Weeks, Daniel J

2013-01-01

Numerous studies have revealed that when people sit next to each other and complete separate parts of a Simon task, response times are shorter when the participants' stimulus appears in front of them than when the stimulus appears in the opposite side of space. According to the action co-representation account of this joint Simon effect (JSE), participants represent each other's responses and the compatibility effects emerge because of a set of facilitatory and inhibitory processes that are similar to those that are activated when individuals perform the entire Simon task alone. D. Guagnano, E. Rusconi, and C. A. Umiltà (2010) argued against this account as the sole mechanism based on their finding that a JSE was not observed when participants sat outside of each other's peripersonal space. Notably, the task in the Guagnano et al.'s was a modified version of the conventional JSE task designed to increase the independence of the partners. Here, we reconsider the arguments of Guagnano et al. and report a study in which the authors failed to replicate their key finding. Considering the extant JSE literature, we conclude that the null effect in Guagnano et al.'s study may be an anomaly and that co-representation remains a leading candidate for the critical process underlying JSEs.

Dysgraphia in Patients with Primary Lateral Sclerosis: A Speech-Based Rehearsal Deficit?

PubMed Central

Zago, S.; Poletti, B.; Corbo, M.; Adobbati, L.; Silani, V.

2008-01-01

The present study aims to demonstrate that errors when writing are more common than expected in patients affected by primary lateral sclerosis (PLS) with severe dysarthria or complete mutism, independent of spasticity. Sixteen patients meeting Pringle’s et al. [34] criteria for PLS underwent standard neuropsychological tasks and evaluation of writing. We assessed writing abilities in spelling through dictation in which a set of words, non-words and short phrases were presented orally and by composing words using a set of preformed letters. Finally, a written copying task was performed with the same words. Relative to controls, PLS patients made a greater number of spelling errors in all writing conditions, but not in copy task. The error types included: omissions, transpositions, insertions and letter substitutions. These were equally distributed on the writing task and the composition of words with a set of preformed letters. This pattern of performance is consistent with a spelling impairment. The results are consistent with the concept that written production is critically dependent on the subvocal articulatory mechanism of rehearsal, perhaps at the level of retaining the sequence of graphemes in a graphemic buffer. In PLS patients a disturbance in rehearsal opportunity may affect the correct sequencing/assembly of an orthographic representation in the written process. PMID:19096141

Faded-example as a Tool to Acquire and Automate Mathematics Knowledge

NASA Astrophysics Data System (ADS)

Retnowati, E.

2017-04-01

Students themselves accomplish Knowledge acquisition and automation. The teacher plays a role as the facilitator by creating mathematics tasks that assist students in building knowledge efficiently and effectively. Cognitive load caused by learning material presented by teachers should be considered as a critical factor. While the intrinsic cognitive load is related to the degree of complexity of the material learning ones can handle, the extraneous cognitive load is directly caused by how the material is presented. Strategies to present a learning material in computational learning domains like mathematics are a namely worked example (fully-guided task) or problem-solving (discovery task with no guidance). According to the empirical evidence, learning based on problem-solving may cause high-extraneous cognitive load for students who have limited prior knowledge, conversely learn based on worked example may cause high-extraneous cognitive load for students who have mastered the knowledge base. An alternative is a faded example consisting of the partly-completed task. Learning from faded-example can facilitate students who already acquire some knowledge about the to-be-learned material but still need more practice to automate the knowledge further. This instructional strategy provides a smooth transition from a fully-guided into an independent problem solver. Designs of faded examples for learning trigonometry are discussed.

Motivational predictors of prosocial and antisocial behaviour in football.

PubMed

Kavussanu, Maria

2006-06-01

This study examined (a) the main and interactive effects of goal orientations and perceived motivational climate on prosocial and antisocial behaviour, and (b) whether number of seasons one has played for the team interacts with motivational climate in predicting prosocial and antisocial behaviour in association football. Participants were 325 male association football players, whose age ranged from 12 to 17 years. Athletes completed questionnaires measuring frequency of prosocial and antisocial behaviours in football, goal orientation, motivational climate and social desirability, and indicated the number of seasons they had played for their current team. Regression analyses revealed that task orientation and mastery climate were positive predictors of prosocial behaviour, whereas ego orientation and performance climate were positive predictors of antisocial behaviour. In addition, task orientation negatively predicted antisocial behaviour, while ego orientation negatively predicted prosocial behaviour. No significant interactions between task and ego orientation and mastery and performance motivational climate were found. Finally, mastery climate negatively predicted antisocial behaviour for those who had played many seasons for the team. In conclusion, strengthening task orientation and mastery climate and weakening ego orientation may enhance prosocial behaviour. However, for antisocial conduct to be eliminated from the context of association football, ego orientation and performance climate need to be tempered, as these constructs exert unique independent effects on antisocial behaviour.

Divided Attention Abilities in Young and Old Adults.

ERIC Educational Resources Information Center

Somberg, Benjamin L.; Salthouse, Timothy A.

1982-01-01

Two experiments on divided attention and adult aging are reported that take into account age differences in single-task performance and that measure divided attention independently of resource allocation strategies. No significant age difference in divided attention ability independent of single-task performance level was found in either…

Filling the gaps: A speeded word fragment completion megastudy.

PubMed

Heyman, Tom; Van Akeren, Liselotte; Hutchison, Keith A; Storms, Gert

2016-12-01

In the speeded word fragment completion task, participants have to complete fragments such as tom_to as quickly and accurately as possible. Previous work has shown that this paradigm can successfully capture subtle priming effects (Heyman, De Deyne, Hutchison, & Storms Behavior Research Methods, 47, 580-606, 2015). In addition, it has several advantages over the widely used lexical decision task. That is, the speeded word fragment completion task is more efficient, more engaging, and easier. Given its potential, we conducted a study to gather speeded word fragment completion norms. The goal of this megastudy was twofold. On the one hand, it provides a rich database of over 8,000 stimuli, which can, for instance, be used in future research to equate stimuli on baseline response times. On the other hand, the aim was to gain insight into the underlying processes of the speeded word fragment completion task. To this end, item-level regression and mixed-effects analyses were performed on the response latencies using 23 predictor variables. Since all items were selected from the Dutch Lexicon Project (Keuleers, Diependaele, & Brysbaert Frontiers in Psychology, 1, 174, 2010), we ran the same analyses on lexical decision latencies to compare the two tasks. Overall, the results revealed many similarities, but also some remarkable differences, which are discussed. We propose that both tasks are complementary when examining visual word recognition. The article ends with a discussion of potential process models of the speeded word fragment completion task.

Cooperation driven coherence: Brains working hard together.

PubMed

Bezerianos, Anastasios; Sun, Yu; Chen, Yu; Woong, Kian Fong; Taya, Fumihiko; Arico, Pietro; Borghini, Gianluca; Babiloni, Fabio; Thakor, Nitish

2015-01-01

The current study aims to look at the difference in coupling of EEG activity of participant pairs while they perform a cooperative, concurrent, independent yet different task at high and low difficulty levels. Participants performed the National Aeronautics and Space Administration (NASA) designed Multi-Attribute Task Battery (MATB-II) task which simulates a pilot and copilot operating an aircraft. Each participant in the pair was responsible for 2 out of 4 subtasks which were independent and different from one another while all tasks occurs concurrently in real time with difficulty levels being the frequency that adjustments are required for each subtask. We found that as the task become more difficult, there was more coupling between the pilot and copilot.

Mission control of multiple unmanned aerial vehicles: a workload analysis.

PubMed

Dixon, Stephen R; Wickens, Christopher D; Chang, Dervon

2005-01-01

With unmanned aerial vehicles (UAVs), 36 licensed pilots flew both single-UAV and dual-UAV simulated military missions. Pilots were required to navigate each UAV through a series of mission legs in one of the following three conditions: a baseline condition, an auditory autoalert condition, and an autopilot condition. Pilots were responsible for (a) mission completion, (b) target search, and (c) systems monitoring. Results revealed that both the autoalert and the autopilot automation improved overall performance by reducing task interference and alleviating workload. The autoalert system benefited performance both in the automated task and mission completion task, whereas the autopilot system benefited performance in the automated task, the mission completion task, and the target search task. Practical implications for the study include the suggestion that reliable automation can help alleviate task interference and reduce workload, thereby allowing pilots to better handle concurrent tasks during single- and multiple-UAV flight control.

Cadaver-Based Simulation Increases Resident Confidence, Initial Exposure to Fundamental Techniques, and May Augment Operative Autonomy.

PubMed

Kim, Steven C; Fisher, Jeremy G; Delman, Keith A; Hinman, Johanna M; Srinivasan, Jahnavi K

Surgical simulation is an important adjunct in surgical education. The majority of operative procedures can be simplified to core components. This study aimed to quantify a cadaver-based simulation course utility in improving exposure to fundamental maneuvers, resident and attending confidence in trainee capability, and if this led to earlier operative independence. A list of fundamental surgical procedures was established by a faculty panel. Residents were assigned to a group led by a chief resident. Residents performed skills on cadavers appropriate for PGY level. A video-recorded examination where they narrated and demonstrated a task independently was then graded by attendings using standardized rubrics. Participants completed surveys regarding improvements in knowledge and confidence. The course was conducted at the Emory University School of Medicine and the T3 Laboratories in Atlanta, GA. A total of 133 residents and 41 attendings participated in the course. 133 (100%) participating residents and 32 (78%) attendings completed surveys. Resident confidence in completing the assigned skill independently increased from 3 (2-3) to 4 (3-4), p < 0.01. Residents stated that a median of 40% (interquartile range: 20%-60%) of procedures were performed for the first time in the course, and the same number had been performed only in the course. The percentage of skills attendings believed residents could perform independently increased from 40% (40%-60%) to 60% (60%->80%), p < 0.04. Attendings were more likely to grant autonomy in the operating room after this exercise (4 [3-5]). A cadaveric skills course focused on fundamental maneuvers with objective confirmation of success is a viable adjunct to clinical operative experience. Residents were formally exposed to fundamental surgical maneuvers earlier as a result of this course. This activity improved both resident and attending confidence in trainee operative skill, resulting in increased attending willingness to grant a higher level of autonomy in the operating room. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Further Analysis of Variables That Affect Self-Control with Aversive Events

ERIC Educational Resources Information Center

Perrin, Christopher J.; Neef, Nancy A.

2012-01-01

The purpose of this study was to examine variables that affect self-control in the context of academic task completion by elementary school children with autism. In the baseline assessment of Study 1, mathematics problem completion was shown to be an aversive event, and sensitivity to task magnitude, task difficulty, and delay to task completion…

Using Task Clarification, Graphic Feedback, and Verbal Feedback to Increase Closing-Task Completion in a Privately Owned Restaurant.

ERIC Educational Resources Information Center

Austin, John; Weatherly, Nic L.; Gravina, Nicole E.

2005-01-01

An informant functional assessment was used to evaluate closing-task completion by servers and dishwashers at a restaurant. Based on the functional assessment results, an intervention consisting of task clarification, posted graphic feedback, and verbal feedback was implemented and evaluated with a multiple baseline design across two groups of…

KENNEDY SPACE CENTER, FLA. - The Stafford-Covey Return to Flight Task Group (SCTG) visits the Columbia Debris Hangar . Chairing the task group are Richard O. Covey (third from right), former Space Shuttle commander, and Thomas P. Stafford (fourth from right), Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

NASA Image and Video Library

2003-08-05

KENNEDY SPACE CENTER, FLA. - The Stafford-Covey Return to Flight Task Group (SCTG) visits the Columbia Debris Hangar . Chairing the task group are Richard O. Covey (third from right), former Space Shuttle commander, and Thomas P. Stafford (fourth from right), Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

A comparison of general and specific instructions to promote task engagement and completion by a young man with Asperger syndrome.

PubMed

Bouxsein, Kelly J; Tiger, Jeffrey H; Fisher, Wayne W

2008-01-01

Previous research has suggested that the topography of instructions (general vs. specific) may influence the likelihood that young children comply with instructions. The purpose of the current study was to compare the rates of task completion of a young man diagnosed with Asperger syndrome when provided with general and specific instructions pertaining to the task. The results showed that specific instructions occasioned higher levels of task completion, even when no differential reinforcement contingencies were in place.

Stimulus information contaminates summation tests of independent neural representations of features

NASA Technical Reports Server (NTRS)

Shimozaki, Steven S.; Eckstein, Miguel P.; Abbey, Craig K.

2002-01-01

Many models of visual processing assume that visual information is analyzed into separable and independent neural codes, or features. A common psychophysical test of independent features is known as a summation study, which measures performance in a detection, discrimination, or visual search task as the number of proposed features increases. Improvement in human performance with increasing number of available features is typically attributed to the summation, or combination, of information across independent neural coding of the features. In many instances, however, increasing the number of available features also increases the stimulus information in the task, as assessed by an optimal observer that does not include the independent neural codes. In a visual search task with spatial frequency and orientation as the component features, a particular set of stimuli were chosen so that all searches had equivalent stimulus information, regardless of the number of features. In this case, human performance did not improve with increasing number of features, implying that the improvement observed with additional features may be due to stimulus information and not the combination across independent features.

Lessons learned from the usability assessment of home-based telemedicine systems.

PubMed

Agnisarman, Sruthy Orozhiyathumana; Chalil Madathil, Kapil; Smith, Kevin; Ashok, Aparna; Welch, Brandon; McElligott, James T

2017-01-01

At-home telemedicine visits are quickly becoming an acceptable alternative for in-person patient visits. However, little work has been done to understand the usability of these home-based telemedicine solutions. It is critical for user acceptance and real-world applicability to evaluate available telemedicine solutions within the context-specific needs of the users of this technology. To address this need, this study evaluated the usability of four home-based telemedicine software platforms: Doxy.me, Vidyo, VSee, and Polycom. Using a within-subjects experimental design, twenty participants were asked to complete a telemedicine session involving several tasks using the four platforms. Upon completion of these tasks for each platform, participants completed the IBM computer system usability questionnaire (CSUQ) and the NASA Task Load Index test. Upon completing the tasks on all four platforms, the participants completed a final post-test subjective questionnaire ranking the platforms based on their preference. Of the twenty participants, 19 completed the study. Statistically significant differences among the telemedicine software platforms were found for task completion time, total workload, mental demand, effort, frustration, preference ranking and computer system usability scores. Usability problems with installation and account creation led to high mental demand and task completion time, suggesting the participants preferred a system without such requirements. Majority of the usability issues were identified at the telemedicine initiation phase. The findings from this study can be used by software developers to develop user-friendly telemedicine systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Test-Takers' Strategic Behaviors in Independent and Integrated Speaking Tasks

ERIC Educational Resources Information Center

Barkaoui, Khaled; Brooks, Lindsay; Swain, Merrill; Lapkin, Sharon

2013-01-01

This study investigated the strategic behaviors that test-takers reported using when responding to integrated and independent speaking tasks in an English oral proficiency test [the Speaking Section of the Internet-based Test of English as a Foreign Language[TM] (TOEFL iBT)] and the relationship between test-takers' strategic behaviors and their…

On the Relationship between Memory and Perception: Sequential Dependencies in Recognition Memory Testing

ERIC Educational Resources Information Center

Malmberg, Kenneth J.; Annis, Jeffrey

2012-01-01

Many models of recognition are derived from models originally applied to perception tasks, which assume that decisions from trial to trial are independent. While the independence assumption is violated for many perception tasks, we present the results of several experiments intended to relate memory and perception by exploring sequential…

Is Field Dependence or Independence a Predictor of EFL Reading Performance

ERIC Educational Resources Information Center

Salmani-Nodoushan, Mohammad Ali

2007-01-01

In this study it was hypothesized that field dependence or independence would introduce systematic variance into Iranian EFL learners' overall and task-specific performance on task-based reading comprehension tests. One thousand, seven hundred, forty-three freshman, sophomore, junior and senior students, all majoring in English at various Iranian…

Neuromodulation of the lumbar spinal locomotor circuit.

PubMed

AuYong, Nicholas; Lu, Daniel C

2014-01-01

The lumbar spinal cord contains the necessary circuitry to independently drive locomotor behaviors. This function is retained following spinal cord injury (SCI) and is amenable to rehabilitation. Although the effectiveness of task-specific training and pharmacologic modulation has been repeatedly demonstrated in animal studies, results from human studies are less striking. Recently, lumbar epidural stimulation (EDS) along with locomotor training was shown to restore weight-bearing function and lower-extremity voluntary control in a chronic, motor-complete human SCI subject. Related animal studies incorporating EDS as part of the therapeutic regiment are also encouraging. EDS is emerging as a promising neuromodulatory tool for SCI. Copyright © 2014 Elsevier Inc. All rights reserved.

A visual surveillance system for person re-identification

NASA Astrophysics Data System (ADS)

El-Alfy, Hazem; Muramatsu, Daigo; Teranishi, Yuuichi; Nishinaga, Nozomu; Makihara, Yasushi; Yagi, Yasushi

2017-03-01

We attempt the problem of autonomous surveillance for person re-identification. This is an active research area, where most recent work focuses on the open challenges of re-identification, independently of prerequisites of detection and tracking. In this paper, we are interested in designing a complete surveillance system, joining all the pieces of the puzzle together. We start by collecting our own dataset from multiple cameras. Then, we automate the process of detection and tracking of human subjects in the scenes, followed by performing the re-identification task. We evaluate the recognition performance of our system, report its strengths, discuss open challenges and suggest ways to address them.

Effects of cue frequency and repetition on prospective memory: an ERP investigation.

PubMed

Wilson, Jennifer; Cutmore, Tim R H; Wang, Ya; Chan, Raymond C K; Shum, David H K

2013-11-01

Prospective memory involves the formation and completion of delayed intentions and is essential for independent living. In this study (n = 33), event-related potentials (ERPs) were used to systematically evaluate the effects of PM cue frequency (10% versus 30%) and PM cue repetition (high versus low) on ERP modulations. PM cues elicited prospective positivity and frontal positivity but not N300, perhaps due to the semantic nature of the task. Results of this study revealed an interesting interaction between PM cue frequency and PM cue repetition for prospective positivity and frontal positivity, highlighting the importance of taking both factors into account when designing future studies. © 2013.

Why Do Students Choose Not to Follow All Instructions When Completing Assessment Tasks?

ERIC Educational Resources Information Center

Fleet, Wendy

2013-01-01

As academics we often assume that allocating marks to a task will influence student decision-making when it comes to completing that task. Marks are used by lecturers to indicate the relative importance of each of the criteria used for marking the assessment task and we expect the student to respond to the marks' allocation. This Postcard suggests…

Cultural pathways through universal development.

PubMed

Greenfield, Patricia M; Keller, Heidi; Fuligni, Andrew; Maynard, Ashley

2003-01-01

We focus our review on three universal tasks of human development: relationship formation, knowledge acquisition, and the balance between autonomy and relatedness at adolescence. We present evidence that each task can be addressed through two deeply different cultural pathways through development: the pathways of independence and interdependence. Whereas core theories in developmental psychology are universalistic in their intentions, they in fact presuppose the independent pathway of development. Because the independent pathway is therefore well-known in psychology, we focus a large part of our review on empirically documenting the alternative, interdependent pathway for each developmental task. We also present three theoretical approaches to culture and development: the ecocultural, the sociohistorical, and the cultural values approach. We argue that an understanding of cultural pathways through human development requires all three approaches. We review evidence linking values (cultural values approach), ecological conditions (ecocultural approach), and socialization practices (sociohistorical approach) to cultural pathways through universal developmental tasks.

Should metacognition be measured by logistic regression?

PubMed

Rausch, Manuel; Zehetleitner, Michael

2017-03-01

Are logistic regression slopes suitable to quantify metacognitive sensitivity, i.e. the efficiency with which subjective reports differentiate between correct and incorrect task responses? We analytically show that logistic regression slopes are independent from rating criteria in one specific model of metacognition, which assumes (i) that rating decisions are based on sensory evidence generated independently of the sensory evidence used for primary task responses and (ii) that the distributions of evidence are logistic. Given a hierarchical model of metacognition, logistic regression slopes depend on rating criteria. According to all considered models, regression slopes depend on the primary task criterion. A reanalysis of previous data revealed that massive numbers of trials are required to distinguish between hierarchical and independent models with tolerable accuracy. It is argued that researchers who wish to use logistic regression as measure of metacognitive sensitivity need to control the primary task criterion and rating criteria. Copyright © 2017 Elsevier Inc. All rights reserved.

Different strategies in solving series completion inductive reasoning problems: an fMRI and computational study.

PubMed

Liang, Peipeng; Jia, Xiuqin; Taatgen, Niels A; Zhong, Ning; Li, Kuncheng

2014-08-01

Neural correlate of human inductive reasoning process is still unclear. Number series and letter series completion are two typical inductive reasoning tasks, and with a common core component of rule induction. Previous studies have demonstrated that different strategies are adopted in number series and letter series completion tasks; even the underlying rules are identical. In the present study, we examined cortical activation as a function of two different reasoning strategies for solving series completion tasks. The retrieval strategy, used in number series completion tasks, involves direct retrieving of arithmetic knowledge to get the relations between items. The procedural strategy, used in letter series completion tasks, requires counting a certain number of times to detect the relations linking two items. The two strategies require essentially the equivalent cognitive processes, but have different working memory demands (the procedural strategy incurs greater demands). The procedural strategy produced significant greater activity in areas involved in memory retrieval (dorsolateral prefrontal cortex, DLPFC) and mental representation/maintenance (posterior parietal cortex, PPC). An ACT-R model of the tasks successfully predicted behavioral performance and BOLD responses. The present findings support a general-purpose dual-process theory of inductive reasoning regarding the cognitive architecture. Copyright © 2014 Elsevier B.V. All rights reserved.

A usability evaluation of four commercial dental computer-based patient record systems

PubMed Central

Thyvalikakath, Thankam P.; Monaco, Valerie; Thambuganipalle, Hima Bindu; Schleyer, Titus

2008-01-01

Background The usability of dental computer-based patient record (CPR) systems has not been studied, despite early evidence that poor usability is a problem for dental CPR system users at multiple levels. Methods The authors conducted formal usability tests of four dental CPR systems by using a purposive sample of four groups of five novice users. The authors measured task outcomes (correctly completed, incorrectly completed and incomplete) in each CPR system while the participants performed nine clinical documentation tasks, as well as the number of usability problems identified in each CPR system and their potential relationship to task outcomes. The authors reviewed the software application design aspects responsible for these usability problems. Results The range for correctly completed tasks was 16 to 64 percent, for incorrectly completed tasks 18 to 38 percent and for incomplete tasks 9 to 47 percent. The authors identified 286 usability problems. The main types were three unsuccessful attempts, negative affect and task incorrectly completed. They also identified six problematic interface and interaction designs that led to usability problems. Conclusion The four dental CPR systems studied have significant usability problems for novice users, resulting in a steep learning curve and potentially reduced system adoption. Clinical Implications The significant number of data entry errors raises concerns about the quality of documentation in clinical practice. PMID:19047669

Does the generation effect occur for pictures?

PubMed

Kinjo, H; Snodgrass, J G

2000-01-01

The generation effect is the finding that self-generated stimuli are recalled and recognized better than read stimuli. The effect has been demonstrated primarily with words. This article examines the effect for pictures in two experiments: Subjects named complete pictures (name condition) and fragmented pictures (generation condition). In Experiment 1, memory was tested in 3 explicit tasks: free recall, yes/no recognition, and a source-monitoring task on whether each picture was complete or fragmented (the complete/incomplete task). The generation effect was found for all 3 tasks. However, in the recognition and source-monitoring tasks, the generation effect was observed only in the generation condition. We hypothesized that absence of the effect in the name condition was due to the sensory or process match effect between study and test pictures and the superior identification of pictures in the name condition. Therefore, stimuli were changed from pictures to their names in Experiment 2. Memory was tested in the recognition task, complete/incomplete task, and second source-monitoring task (success/failure) on whether each picture had been identified successfully. The generation effect was observed for all 3 tasks. These results suggest that memory of structural and semantic characteristics and of success in identification of generated pictures may contribute to the generation effect.

What Is the Influence of Morphological Knowledge in the Early Stages of Reading Acquisition Among Low SES Children? A Graphical Modeling Approach

PubMed Central

Colé, Pascale; Cavalli, Eddy; Duncan, Lynne G.; Theurel, Anne; Gentaz, Edouard; Sprenger-Charolles, Liliane; El-Ahmadi, Abdessadek

2018-01-01

Children from low-SES families are known to show delays in aspects of language development which underpin reading acquisition such as vocabulary and listening comprehension. Research on the development of morphological skills in this group is scarce, and no studies exist in French. The present study investigated the involvement of morphological knowledge in the very early stages of reading acquisition (decoding), before reading comprehension can be reliably assessed. We assessed listening comprehension, receptive vocabulary, phoneme awareness, morphological awareness as well as decoding, word reading and non-verbal IQ in 703 French first-graders from low-SES families after 3 months of formal schooling (November). Awareness of derivational morphology was assessed using three oral tasks: Relationship Judgment (e.g., do these words belong to the same family or not? heat-heater … ham-hammer); Lexical Sentence Completion [e.g., Someone who runs is a …? (runner)]; and Non-lexical Sentence Completion [e.g., Someone who lums is a…? (lummer)]. The tasks differ on implicit/explicit demands and also tap different kinds of morphological knowledge. The Judgement task measures the phonological and semantic properties of the morphological relationship and the Sentence Completion tasks measure knowledge of morphological production rules. Data were processed using a graphical modeling approach which offers key information about how skills known to be involved in learning to read are organized in memory. This modeling approach was therefore useful in revealing a potential network which expresses the conditional dependence structure between skills, after which recursive structural equation modeling was applied to test specific hypotheses. Six main conclusions can be drawn from these analyses about low SES reading acquisition: (1) listening comprehension is at the heart of the reading acquisition process; (2) word reading depends directly on phonemic awareness and indirectly on listening comprehension; (3) decoding depends on word reading; (4) Morphological awareness and vocabulary have an indirect influence on word reading via both listening comprehension and phoneme awareness; (5) the components of morphological awareness assessed by our tasks have independent relationships with listening comprehension; and (6) neither phonemic nor morphological awareness influence vocabulary directly. The implications of these results with regard to early reading acquisition among low SES groups are discussed. PMID:29725313

What Is the Influence of Morphological Knowledge in the Early Stages of Reading Acquisition Among Low SES Children? A Graphical Modeling Approach.

PubMed

Colé, Pascale; Cavalli, Eddy; Duncan, Lynne G; Theurel, Anne; Gentaz, Edouard; Sprenger-Charolles, Liliane; El-Ahmadi, Abdessadek

2018-01-01

Children from low-SES families are known to show delays in aspects of language development which underpin reading acquisition such as vocabulary and listening comprehension. Research on the development of morphological skills in this group is scarce, and no studies exist in French. The present study investigated the involvement of morphological knowledge in the very early stages of reading acquisition (decoding), before reading comprehension can be reliably assessed. We assessed listening comprehension, receptive vocabulary, phoneme awareness, morphological awareness as well as decoding, word reading and non-verbal IQ in 703 French first-graders from low-SES families after 3 months of formal schooling (November). Awareness of derivational morphology was assessed using three oral tasks: Relationship Judgment (e.g., do these words belong to the same family or not? heat-heater … ham-hammer); Lexical Sentence Completion [e.g., Someone who runs is a …? (runner)]; and Non-lexical Sentence Completion [e.g., Someone who lums is a…? (lummer)]. The tasks differ on implicit/explicit demands and also tap different kinds of morphological knowledge. The Judgement task measures the phonological and semantic properties of the morphological relationship and the Sentence Completion tasks measure knowledge of morphological production rules. Data were processed using a graphical modeling approach which offers key information about how skills known to be involved in learning to read are organized in memory. This modeling approach was therefore useful in revealing a potential network which expresses the conditional dependence structure between skills, after which recursive structural equation modeling was applied to test specific hypotheses. Six main conclusions can be drawn from these analyses about low SES reading acquisition: (1) listening comprehension is at the heart of the reading acquisition process; (2) word reading depends directly on phonemic awareness and indirectly on listening comprehension; (3) decoding depends on word reading; (4) Morphological awareness and vocabulary have an indirect influence on word reading via both listening comprehension and phoneme awareness; (5) the components of morphological awareness assessed by our tasks have independent relationships with listening comprehension; and (6) neither phonemic nor morphological awareness influence vocabulary directly. The implications of these results with regard to early reading acquisition among low SES groups are discussed.

When 1+1=1: the unification of independent actors revealed through joint Simon effects in crossed and uncrossed effector conditions.

PubMed

Welsh, Timothy N

2009-12-01

The "Simon effect" describes a pattern of reaction times (RTs) where responses to symbolic information are shorter when the information is presented on the same side of space as the desired response than when it is on the opposite side of space. For example, if right hand responses are required for green targets and left hand responses for red targets, RTs with the right hand are shorter when the green target appears on the right side than on the left side. It has been reported that Simon effects also appear when two individuals perform independent components of a Simon effect task. It has been suggested that such joint Simon effects occur because participants represent the action of their partner. It is unclear, however, if the joint Simon effect emerges because: (1) each partner represents the other's action; (2) each partner is using the other person or their response as an environmental reference; or (3) an intra-hemispheric processing advantage due to the lateralized cerebral organization of perceptual and motor systems. The present study distinguished between these possibilities by asking pairs of participants to perform in conditions in which they crossed their arms into the other person's space. Consistent with within-person Simon effects, joint Simon effects were observed in uncrossed- and crossed limb conditions. These results support a response co-representation explanation of joint Simon effects. It is suggested that the processes underlying the evoked representations have developed to allow two independent agents to form temporary synergies to facilitate efficient task completion. 2009 Elsevier B.V. All rights reserved.

Compound risk judgment in tasks with both idiosyncratic and systematic risk: The "Robust Beauty" of additive probability integration.

PubMed

Sundh, Joakim; Juslin, Peter

2018-02-01

In this study, we explore how people integrate risks of assets in a simulated financial market into a judgment of the conjunctive risk that all assets decrease in value, both when assets are independent and when there is a systematic risk present affecting all assets. Simulations indicate that while mental calculation according to naïve application of probability theory is best when the assets are independent, additive or exemplar-based algorithms perform better when systematic risk is high. Considering that people tend to intuitively approach compound probability tasks using additive heuristics, we expected the participants to find it easiest to master tasks with high systematic risk - the most complex tasks from the standpoint of probability theory - while they should shift to probability theory or exemplar memory with independence between the assets. The results from 3 experiments confirm that participants shift between strategies depending on the task, starting off with the default of additive integration. In contrast to results in similar multiple cue judgment tasks, there is little evidence for use of exemplar memory. The additive heuristics also appear to be surprisingly context-sensitive, with limited generalization across formally very similar tasks. Copyright © 2017 Elsevier B.V. All rights reserved.

Naturalistic Assessment of Everyday Activities and Prompting Technologies in Mild Cognitive Impairment

PubMed Central

Seelye, Adriana M.; Schmitter-Edgecombe, Maureen; Cook, Diane J.; Crandall, Aaron

2014-01-01

Older adults with mild cognitive impairment (MCI) often have difficulty performing complex instrumental activities of daily living (IADLs), which are critical to independent living. In this study, amnestic multi-domain MCI (N = 29), amnestic single-domain MCI (N = 18), and healthy older participants (N = 47) completed eight scripted IADLs (e.g., cook oatmeal on the stove) in a smart apartment testbed. We developed and experimented with a graded hierarchy of technology-based prompts to investigate both the amount of prompting and type of prompts required to assist individuals with MCI in completing the activities. When task errors occurred, progressive levels of assistance were provided, starting with the lowest level needed to adjust performance. Results showed that the multi-domain MCI group made more errors and required more prompts than the single-domain MCI and healthy older adult groups. Similar to the other two groups, the multi-domain MCI group responded well to the indirect prompts and did not need a higher level of prompting to get back on track successfully with the tasks. Need for prompting assistance was best predicted by verbal memory abilities in multi-domain amnestic MCI. Participants across groups indicated that they perceived the prompting technology to be very helpful. PMID:23351284

The disruptive effects of pain on multitasking in a virtual errands task.

PubMed

Moore, David J; Law, Anna S

2017-07-01

Pain is known to have a disruptive effect on cognitive performance, but prior studies have used highly constrained laboratory tasks that lack ecological validity. In everyday life people are required to complete more complex sets of tasks, prioritising task completion and recalling lists of tasks which need to be completed, and these tasks continue to be attempted during episodes or states of pain. The present study therefore examined the impact of thermal induced pain on a simulated errand task. Fifty-five healthy adults (36 female) performed the Edinburgh Virtual Errands Task (EVET) either during a painful thermal sensation or with no concurrent pain. Participants also completed the Experience of Cognitive Intrusion of Pain (ECIP) questionnaire to measure their self-reported cognitive impact of pain in general life. Participants who completed the EVET task in pain and who self-reported high intrusion of pain made significantly more errors than those who reported lower intrusion on the ECIP. Findings here support the growing literature that suggests that pain has a significant impact on cognitive performance. Furthermore, these findings support the developing literature suggesting that this relationship is complex when considering real world cognition, and that self-report on the ECIP relates well to performance on a task designed to reflect the complexities of everyday living. If extrapolated to chronic pain populations, these data suggest that pain during complex multitasking performance may have a significant impact on the number of errors made. For people highly vulnerable to cognitive intrusion by pain, this may result in errors such as selecting the wrong location or item to perform tasks, or forgetting to perform these tasks at the correct time. If these findings are shown to extend to chronic pain populations then occupational support to manage complex task performance, using for example diaries/electronic reminders, may help to improve everyday abilities. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

KENNEDY SPACE CENTER, FLA. - In the Columbia Debris Hangar, members of the Stafford-Covey Return to Flight Task Group (SCTG) look at tiles recovered. Chairing the task group are Richard O. Covey, former Space Shuttle commander, and Thomas P. Stafford (center), Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

NASA Image and Video Library

2003-08-05

KENNEDY SPACE CENTER, FLA. - In the Columbia Debris Hangar, members of the Stafford-Covey Return to Flight Task Group (SCTG) look at tiles recovered. Chairing the task group are Richard O. Covey, former Space Shuttle commander, and Thomas P. Stafford (center), Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

KENNEDY SPACE CENTER, FLA. - In the Columbia Debris Hangar, members of the Stafford-Covey Return to Flight Task Group (SCTG) inspect some of the debris. Chairing the task group are Richard O. Covey, former Space Shuttle commander, and Thomas P. Stafford (fourth from left), Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

NASA Image and Video Library

2003-08-05

KENNEDY SPACE CENTER, FLA. - In the Columbia Debris Hangar, members of the Stafford-Covey Return to Flight Task Group (SCTG) inspect some of the debris. Chairing the task group are Richard O. Covey, former Space Shuttle commander, and Thomas P. Stafford (fourth from left), Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

7 CFR 1709.117 - Application requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... project including target community, goals, tasks to be completed and other relevant information that... to support a finding of technical feasibility; (ii) Identify the major tasks to be performed and a proposed timeline for completion of each task; and (iii) Identify the location of the project target area...

Transferability of Dual-Task Coordination Skills after Practice with Changing Component Tasks

PubMed Central

Schubert, Torsten; Liepelt, Roman; Kübler, Sebastian; Strobach, Tilo

2017-01-01

Recent research has demonstrated that dual-task performance with two simultaneously presented tasks can be substantially improved as a result of practice. Among other mechanisms, theories of dual-task practice-relate this improvement to the acquisition of task coordination skills. These skills are assumed (1) to result from dual-task practice, but not from single-task practice, and (2) to be independent from the specific stimulus and response mappings during the practice situation and, therefore, transferable to new dual task situations. The present study is the first that provides an elaborated test of these assumptions in a context with well-controllable practice and transfer situations. To this end, we compared the effects of dual-task and single-task practice with a visual and an auditory sensory-motor component task on the dual-task performance in a subsequent transfer session. Importantly, stimulus and stimulus-response mapping conditions in the two component tasks changed repeatedly during practice sessions, which prevents that automatized stimulus-response associations may be transferred from practice to transfer. Dual-task performance was found to be improved after practice with the dual tasks in contrast to the single-task practice. These findings are consistent with the assumption that coordination skills had been acquired, which can be transferred to other dual-task situations independently on the specific stimulus and response mapping conditions of the practiced component tasks. PMID:28659844

Time crawls when you're not having fun: feeling entitled makes dull tasks drag on.

PubMed

O'Brien, Edward H; Anastasio, Phyllis A; Bushman, Brad J

2011-10-01

All people have to complete dull tasks, but individuals who feel entitled may be more inclined to perceive them as a waste of their "precious" time, resulting in the perception that time drags. This hypothesis was confirmed in three studies. In Study 1, participants with higher trait entitlement (controlling for related variables) thought dull tasks took longer to complete; no link was found for fun tasks. In Study 2, participants exposed to entitled messages thought taking a dull survey was a greater waste of time and took longer to complete. In Study 3, participants subliminally exposed to entitled words thought dull tasks were less interesting, thought they took longer to complete, and walked away faster when leaving the laboratory. Like most resources, time is a resource valued more by entitled individuals. A time-entitlement link provides novel insight into mechanisms underlying self-focus and prosocial dynamics.

Usability Evaluation of an Unstructured Clinical Document Query Tool for Researchers.

PubMed

Hultman, Gretchen; McEwan, Reed; Pakhomov, Serguei; Lindemann, Elizabeth; Skube, Steven; Melton, Genevieve B

2018-01-01

Natural Language Processing - Patient Information Extraction for Researchers (NLP-PIER) was developed for clinical researchers for self-service Natural Language Processing (NLP) queries with clinical notes. This study was to conduct a user-centered analysis with clinical researchers to gain insight into NLP-PIER's usability and to gain an understanding of the needs of clinical researchers when using an application for searching clinical notes. Clinical researcher participants (n=11) completed tasks using the system's two existing search interfaces and completed a set of surveys and an exit interview. Quantitative data including time on task, task completion rate, and survey responses were collected. Interviews were analyzed qualitatively. Survey scores, time on task and task completion proportions varied widely. Qualitative analysis indicated that participants found the system to be useful and usable in specific projects. This study identified several usability challenges and our findings will guide the improvement of NLP-PIER 's interfaces.

N-back versus Complex Span Working Memory Training.

PubMed

Blacker, Kara J; Negoita, Serban; Ewen, Joshua B; Courtney, Susan M

2017-12-01

Working memory (WM) is the ability to maintain and manipulate task-relevant information in the absence of sensory input. While its improvement through training is of great interest, the degree to which WM training transfers to untrained WM tasks (near transfer) and other untrained cognitive skills (far transfer) remains debated and the mechanism(s) underlying transfer are unclear. Here we hypothesized that a critical feature of dual n-back training is its reliance on maintaining relational information in WM. In Experiment 1, using an individual differences approach, we found evidence that performance on an n-back task was predicted by performance on a measure of relational WM (i.e., WM for vertical spatial relationships independent of absolute spatial locations); whereas the same was not true for a complex span WM task. In Experiment 2, we tested the idea that reliance on relational WM is critical to produce transfer from n-back but not complex span task training. Participants completed adaptive training on either a dual n-back task, a symmetry span task, or on a non-WM active control task. We found evidence of near transfer for the dual n-back group; however, far transfer to a measure of fluid intelligence did not emerge. Recording EEG during a separate WM transfer task, we examined group-specific, training-related changes in alpha power, which are proposed to be sensitive to WM demands and top-down modulation of WM. Results indicated that the dual n-back group showed significantly greater frontal alpha power after training compared to before training, more so than both other groups. However, we found no evidence of improvement on measures of relational WM for the dual n-back group, suggesting that near transfer may not be dependent on relational WM. These results suggest that dual n-back and complex span task training may differ in their effectiveness to elicit near transfer as well as in the underlying neural changes they facilitate.

Report of the Cost Assessment and Validation Task Force on the International Space Station

NASA Technical Reports Server (NTRS)

1998-01-01

The Cost Assessment and Validation (CAV) Task Force was established for independent review and assessment of cost, schedule and partnership performance on the International Space Station (ISS) Program. The CAV Task Force has made the following key findings: The International Space Station Program has made notable and reasonable progress over the past four years in defining and executing a very challenging and technically complex effort. The Program size, complexity, and ambitious schedule goals were beyond that which could be reasonably achieved within the $2.1 billion annual cap or $17.4 billion total cap. A number of critical risk elements are likely to have an adverse impact on the International Space Station cost and schedule. The schedule uncertainty associated with Russian implementation of joint Partnership agreements is the major threat to the ISS Program. The Fiscal Year (FY) 1999 budget submission to Congress is not adequate to execute the baseline ISS Program, cover normal program growth, and address the known critical risks. Additional annual funding of between $130 million and $250 million will be required. Completion of ISS assembly is likely to be delayed from one to three years beyond December 2003.

Cost Assessment and Validation Task Force on the International Space Station

NASA Technical Reports Server (NTRS)

1998-01-01

The Cost Assessment and Validation (CAV) Task Force was established for independent review and assessment of cost, schedule and partnership performance on the International Space Station (ISS) Program. The CAV Task Force has made the following key findings: The International Space Station Program has made notable and reasonable progress over the past four years in defining and executing a very challenging and technically complex effort; The Program, size, complexity, and ambitious schedule goals were beyond that which could be reasonably achieved within the $2.1 billion annual cap or $17.4 billion total cap; A number of critical risk elements are likely to have an adverse impact on the International Space Station cost and schedule; The schedule uncertainty associated with Russian implementation of joint Partnership agreements is the major threat to the ISS Program; The Fiscal Year (FY) 1999 budget submission to Congress is not adequate to execute the baseline ISS Program, cover normal program, growth, and address the known critical risks. Additional annual funding of between $130 million and $250 million will be required; and Completion of ISS assembly is likely to be delayed from, one to three years beyond December 2003.

Exploring nursing staffs communication in stressful and non-stressful situations.

PubMed

André, Beate; Frigstad, Sigrun A; Nøst, Torunn H; Sjøvold, Endre

2016-03-01

To explore the factors that characterise the work environment, focusing on communication among nurses in stressful and non-stressful situations. Nursing is often described as a stressful occupation. Implementation of change may be an additional stress factor. Nurses and assistant nurses completed a questionnaire from two different perspectives, 'communication in non-stressful situations' and 'communication under stress'. The Systematising Person-Group Relations method was used to gather and analyse the data. When the two perspectives, 'communication in non-stressful situations' and 'communication under stress', were compared, there were significant differences in 8 of the 12 factors. The stressful situations were characterised by low values in task orientation, caring, criticism, loyalty, acceptance, engagement and empathy; only the factor creativity had higher scores. The stressful situations were characterised by creative and spontaneous behaviour, not by task orientation and engagement, indicating a potential patient safety risk. There is a need to help health-care workers develop more mature analytical and task-oriented behaviours related to both independent work and collaboration in stressful situations. Nursing leadership and organisation must focus on healthy work environments to promote engaged communication in stressful situations, ultimately increasing patient safety. © 2015 The Authors. Journal of Nursing Management Published by John Wiley & Sons Ltd.

Interacting with notebook input devices: an analysis of motor performance and users' expertise.

PubMed

Sutter, Christine; Ziefle, Martina

2005-01-01

In the present study the usability of two different types of notebook input devices was examined. The independent variables were input device (touchpad vs. mini-joystick) and user expertise (expert vs. novice state). There were 30 participants, of whom 15 were touchpad experts and the other 15 were mini-joystick experts. The experimental tasks were a point-click task (Experiment 1) and a point-drag-drop task (Experiment 2). Dependent variables were the time and accuracy of cursor control. To assess carryover effects, we had the participants complete both experiments, using not only the input device for which they were experts but also the device for which they were novices. Results showed the touchpad performance to be clearly superior to mini-joystick performance. Overall, experts showed better performance than did novices. The significant interaction of input device and expertise showed that the use of an unknown device is difficult, but only for touchpad experts, who were remarkably slower and less accurate when using a mini-joystick. Actual and potential applications of this research include an evaluation of current notebook input devices. The outcomes allow ergonomic guidelines to be derived for optimized usage and design of the mini-joystick and touchpad devices.

Assessment of Functional Change and Cognitive Correlates in the Progression from Healthy Cognitive Aging to Dementia

PubMed Central

Schmitter-Edgecombe, Maureen; Parsey, Carolyn M.

2014-01-01

Objective There is currently limited understanding of the course of change in everyday functioning that occurs with normal aging and dementia. To better characterize the nature of this change, we evaluated the types of errors made by participants as they performed everyday tasks in a naturalistic environment. Method Participants included cognitively healthy younger adults (YA; N = 55) and older adults (OA; N =88), and individuals with mild cognitive impairment (MCI: N =55) and dementia (N = 18). Participants performed eight scripted everyday activities (e.g., filling a medication dispenser) while under direct observation in a campus apartment. Task performances were coded for the following errors: inefficient actions, omissions, substitutions, and irrelevant actions. Results Performance accuracy decreased with age and level of cognitive impairment. Relative to the YAs, the OA group exhibited more inefficient actions which were linked to performance on neuropsychological measures of executive functioning. Relative to the OAs, the MCI group committed significantly more omission errors which were strongly linked to performance on memory measures. All error types were significantly more prominent in individuals with dementia. Omission errors uniquely predicted everyday functional status as measured by both informant-report and a performance-based measure. Conclusions These findings suggest that in the progression from healthy aging to MCI, everyday task difficulties may evolve from task inefficiencies to task omission errors, leading to inaccuracies in task completion that are recognized by knowledgeable informants. Continued decline in cognitive functioning then leads to more substantial everyday errors, which compromise ability to live independently. PMID:24933485

Knowledge-based system verification and validation

NASA Technical Reports Server (NTRS)

Johnson, Sally C.

1990-01-01

The objective of this task is to develop and evaluate a methodology for verification and validation (V&V) of knowledge-based systems (KBS) for space station applications with high reliability requirements. The approach consists of three interrelated tasks. The first task is to evaluate the effectiveness of various validation methods for space station applications. The second task is to recommend requirements for KBS V&V for Space Station Freedom (SSF). The third task is to recommend modifications to the SSF to support the development of KBS using effectiveness software engineering and validation techniques. To accomplish the first task, three complementary techniques will be evaluated: (1) Sensitivity Analysis (Worchester Polytechnic Institute); (2) Formal Verification of Safety Properties (SRI International); and (3) Consistency and Completeness Checking (Lockheed AI Center). During FY89 and FY90, each contractor will independently demonstrate the user of his technique on the fault detection, isolation, and reconfiguration (FDIR) KBS or the manned maneuvering unit (MMU), a rule-based system implemented in LISP. During FY91, the application of each of the techniques to other knowledge representations and KBS architectures will be addressed. After evaluation of the results of the first task and examination of Space Station Freedom V&V requirements for conventional software, a comprehensive KBS V&V methodology will be developed and documented. Development of highly reliable KBS's cannot be accomplished without effective software engineering methods. Using the results of current in-house research to develop and assess software engineering methods for KBS's as well as assessment of techniques being developed elsewhere, an effective software engineering methodology for space station KBS's will be developed, and modification of the SSF to support these tools and methods will be addressed.

Plantar loading during cutting while wearing a rigid carbon fiber insert.

PubMed

Queen, Robin M; Abbey, Alicia N; Verma, Ravi; Butler, Robert J; Nunley, James A

2014-01-01

Stress fractures are one of the most common injuries in sports, accounting for approximately 10% of all overuse injuries. Treatment of fifth metatarsal stress fractures involves both surgical and nonsurgical interventions. Fifth metatarsal stress fractures are difficult to treat because of the risks of delayed union, nonunion, and recurrent injuries. Most of these injuries occur during agility tasks, such as those performed in soccer, basketball, and lacrosse. To examine the effect of a rigid carbon graphite footplate on plantar loading during 2 agility tasks. Crossover study. Laboratory. A total of 19 recreational male athletes with no history of lower extremity injury in the past 6 months and no previous metatarsal stress fractures were tested. Seven 45° side-cut and crossover-cut tasks were completed in a shoe with or without a full-length rigid carbon plate. Testing order between the shoe conditions and the 2 cutting tasks was randomized. Plantar-loading data were recorded using instrumented insoles. Peak pressure, maximum force, force-time integral, and contact area beneath the total foot, the medial and lateral midfoot, and the medial, middle, and lateral forefoot were analyzed. A series of paired t tests was used to examine differences between the footwear conditions (carbon graphite footplate, shod) for both cutting tasks independently (α = .05). During the side-cut task, the footplate increased total foot and lateral midfoot peak pressures while decreasing contact area and lateral midfoot force-time integral. During the crossover-cut task, the footplate increased total foot and lateral midfoot peak pressure and lateral forefoot force-time integral while decreasing total and lateral forefoot contact area. Although a rigid carbon graphite footplate altered some aspects of the plantar-pressure profile during cutting in uninjured participants, it was ineffective in reducing plantar loading beneath the fifth metatarsal.

Applying systems thinking to task shifting for mental health using lay providers: a review of the evidence.

PubMed

Javadi, D; Feldhaus, I; Mancuso, A; Ghaffar, A

2017-01-01

This paper seeks to review the available evidence to determine whether a systems approach is employed in the implementation and evaluation of task shifting for mental health using lay providers in low- and middle-income countries, and to highlight system-wide effects of task-shifting strategies in order to better inform efforts to strength community mental health systems. Pubmed, CINAHL, and Cochrane Library databases were searched. Articles were screened by two independent reviewers with a third reviewer resolving discrepancies. Two stages of screens were done to ensure sensitivity. Studies were analysed using the World Health Organization's building blocks framework with the addition of a community building block, and systems thinking characteristics to determine the extent to which system-wide effects had been considered. Thirty studies were included. Almost all studies displayed positive findings on mental health using task shifting. One study showed no effect. No studies explicitly employed systems thinking tools, but some demonstrated systems thinking characteristics, such as exploring various stakeholder perspectives, capturing unintended consequences, and looking across sectors for system-wide impact. Twenty-five of the 30 studies captured elements other than the most directly relevant building blocks of service delivery and health workforce. There is a lack of systematic approaches to exploring complexity in the evaluation of task-shifting interventions. Systems thinking tools should support evidence-informed decision making for a more complete understanding of community-based systems strengthening interventions for mental health.

Impact of police body armour and equipment on mobility.

PubMed

Dempsey, Paddy C; Handcock, Phil J; Rehrer, Nancy J

2013-11-01

Body armour is used widely by law enforcement and other agencies but has received mixed reviews. This study examined the influence of stab resistant body armour (SRBA) and mandated accessories on physiological responses to, and the performance of, simulated mobility tasks. Fifty-two males (37 ± 9.2 yr, 180.7 ± 6.1 cm, 90.2 ± 11.6 kg, VO2max 50 ± 8.5 ml kg(-1) min(-1), BMI 27.6 ± 3.1, mean ± SD) completed a running VO2max test and task familiarisation. Two experimental sessions were completed (≥4 days in between) in a randomised counterbalanced order, one while wearing SRBA and appointments (loaded) and one without additional load (unloaded). During each session participants performed five mobility tasks: a balance task, an acceleration task that simulated exiting a vehicle, chin-ups, a grappling task, and a manoeuvrability task. A 5-min treadmill run (zero-incline at 13 km·h(-1), running start) was then completed. One min after the run the five mobility tasks were repeated. There was a significant decrease in performance during all tasks with loading (p < 0.001). Participants were off-balance longer; slower to complete the acceleration, grapple and mobility tasks; completed fewer chin-ups; and had greater physiological cost (↑ %HRmax, ↑ %VO2max, ↑ RER) and perceptual effort (↑ RPE) during the 5-min run. Mean performance decreases ranged from 13 to 42% while loaded, with further decreases of 6-16% noted after the 5-min run. Unloaded task performance was no different between phases. Wearing SRBA and appointments significantly reduced mobility during key task elements and resulted in greater physiological effort. These findings could have consequences for optimal function in the working environment and therefore officer and public safety. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

The fate of completed intentions.

PubMed

Anderson, Francis T; Einstein, Gilles O

2017-04-01

The goal of this research was to determine whether and how people deactivate prospective memory (PM) intentions after they have been completed. One view proposes that PM intentions can be deactivated after completion, such that they no longer come to mind and interfere with current tasks. Another view is that now irrelevant completed PM intentions exhibit persisting activation, and continue to be retrieved. In Experiment 1, participants were given a PM intention embedded within the ongoing task during Phase 1, after which participants were told either that the PM task had been completed or suspended until later. During Phase 2, participants were instructed to perform only the ongoing task and were periodically prompted to report their thoughts. Critically, the PM targets from Phase 1 reappeared in Phase 2. All of our measures, including thoughts reported about the PM task, supported the existence of persisting activation. In Experiment 2, we varied conditions that were expected to mitigate persisting activation. Despite our best attempts to promote deactivation, we found evidence for the persistence of spontaneous retrieval in all groups after intentions were completed. The theoretical and practical implications of this potential dark side to spontaneous retrieval are discussed.

Assessing the Relationship between Vitamin D Status and Impairments in Cognitive and Physical Performance in Older Adults Using a Dual Task Physical Performance Test.

PubMed

Lopez, J; Campa, A; Lewis, J E; Huffman, F G; Liuzzi, J P; Li, T; Martinez, A H; Ferris, S M; Rasul, A; Farooqi, A; Lopez Medrano, A M; Atlas, S E; Tiozzo, E; Konefal, J; Woolger, J M

2017-01-01

Vitamin D deficiency has been associated with an increased risk of falls in older adults. Several studies have demonstrated an association between vitamin D deficiency and gait and cognitive impairments, which are two risk factors for falls in the elderly. There is lack of research about the role of vitamin D in cognitive function in the context of mobility. The purpose of this study was to evaluate the association between vitamin D status with the age-related changes in mobility through higher order cognitive function using a dual task physical performance test. Cross-sectional. Community-dwelling older adult population located in Miami, Fl. Healthy participants over the age of 55 (n=97) who participated in the parent interventional study. Participants completed assessments that included serum levels of vitamin D, surveys, and dual task physical performance tests. Spearman's correlations, independent t-tests, repeated measures ANOVAs and multiple logistic regressions were used to examine the relationship between vitamin D insufficiency (25-hydroxyvitamin D <30 ng/ml) and sufficiency (≥30 ng/ml) and dual task physical performance variables. The significance level was set at α=0.05. There were no significant associations between vitamin D insufficiency and gait velocity during either task. Using Spearman correlations, slower single (P=0.011) and dual task counting rates (P=0.006) were significantly associated with vitamin D insufficiency. Independent t-tests showed dual and single task counting rates were significantly lower in the vitamin D insufficient group compared to the sufficient group (P=0.018 and P=0.028, respectively). The results for the ANOVAs indicated that velocities and counting rates were not significantly different by vitamin D status (Wilk's Lambda =0.999; F (1, 95) =.11, P=.740) (Wilk's Lambda =.999, F(1,95)=.13, P=.718). Vitamin D status was not significantly associated with dual task physical performance (defined as the difference in dual and single task) in gait velocity (OR=1.00, 95% CI: 0.98; 1.02, P=0.772) and counting rate (OR=1.684, 95% CI: 0.15; 19.57, P=0.677), when controlling for confounders. Since counting backward is a mental tracking task, which is a component of executive function, our results suggest a relationship between vitamin D insufficiency and executive dysfunction. Executive dysfunction has been previously associated with fall risks in the elderly, and it could be a possible mediator between vitamin D and falls. Our data suggest that cognition may play a significant role in vitamin D's influence on falls, while motor function may play a lesser role.

Better control with less effort: The advantage of using focused-breathing strategy over focused-distraction strategy on thought suppression.

PubMed

Ju, Yu-Jeng; Lien, Yunn-Wen

2016-02-01

It has been suggested that unwanted thoughts usually intrude during mind wandering due to a shortage of mental resources. However, strategies for suppressing such thoughts have never been examined from a mind wandering perspective. Here, we compare the effectiveness of two types of attention distraction strategies that either redirect users' attention to their own breathing (focused-breathing strategy, FBS) or to a mental image (focused-distraction strategy, FDS) as related to working memory capacities. Eighty-two undergraduates were randomly assigned into a FBS or FDS group. They completed a concentration task and a thought suppression task, in which mind wandering and thought intrusions were each measured. Our results support the hypothesis that mind wandering is positively correlated to thought intrusions and shows that FBS is more effective than FDS in reducing mind wandering and thought intrusions. Moreover, in contrast to FDS, the effect of FBS is independent of users' mental resources. Copyright © 2015 Elsevier Inc. All rights reserved.

Is death really the worm at the core? Converging evidence that worldview threat increases death-thought accessibility.

PubMed

Schimel, Jeff; Hayes, Joseph; Williams, Todd; Jahrig, Jesse

2007-05-01

According to terror management theory, if the cultural worldview protects people from thoughts about death, then weakening this structure should increase death-thought accessibility (DTA). Five studies tested this DTA hypothesis. Study 1 showed that threatening Canadian participants' cultural values (vs. those of another culture) increased DTA on a word-fragment completion task. Study 2 showed that when participants could dismiss the threat, DTA remained low. Study 3 replicated the results of Study 1, but DTA was measured using a lexical decision task. Response latencies to death, negative, and neutral content were measured. Worldview threat increased DTA relative to accessibility for negative and neutral content. Study 4 showed that the DTA effect emerged independently of the arousal of anger or anxiety. Finally, Study 5 demonstrated that participants with a pro-creation (vs. pro-evolution) worldview had higher DTA after reading an anti-creation article. Discussion focused on theoretical implications and directions for further research. ((c) 2007 APA, all rights reserved).

Deficit in implicit motor sequence learning among children and adolescents with spastic cerebral palsy.

PubMed

Gofer-Levi, Moran; Silberg, Tamar; Brezner, Amichai; Vakil, Eli

2013-11-01

Skill learning (SL) is learning as a result of repeated exposure and practice, which encompasses independent explicit (response to instructions) and implicit (response to hidden regularities) processes. Little is known about the effects of developmental disorders, such as Cerebral Palsy (CP), on the ability to acquire new skills. We compared performance of CP and typically developing (TD) children and adolescents in completing the serial reaction time (SRT) task, which is a motor sequence learning task, and examined the impact of various factors on this performance as indicative of the ability to acquire motor skills. While both groups improved in performance, participants with CP were significantly slower than TD controls and did not learn the implicit sequence. Our results indicate that SL in children and adolescents with CP is qualitatively and quantitatively different than that of their peers. Understanding the unique aspects of SL in children and adolescents with CP might help plan appropriate and efficient interventions. Copyright © 2013 Elsevier Ltd. All rights reserved.

The rehabilitation team: staff perceptions of the hospital environment, the interdisciplinary team environment, and interprofessional relations.

PubMed

Strasser, D C; Falconer, J A; Martino-Saltzmann, D

1994-02-01

Although inpatient rehabilitation is an interdisciplinary activity organized around a treatment team, there is a limited understanding of the workings of the interdisciplinary process. To elucidate staff perceptions of key aspects of the rehabilitation treatment process, we surveyed staff (n = 113) from selected inpatient teams. The staff completed social psychological instruments that measure perceptions of the hospital environment (The Ward Atmosphere Scale [WAS]), the team's environment (the Group Environment Scale [GES]), and interprofessional relations (Interprofessional Perception Scale [IPS]). Rehabilitation staff generally endorse the team approach, but express concerns over professional boundaries. Interprofessional difficulties seemed to be independent of team membership or professional training. Compared with published data from other settings, rehabilitation teams resembled task-oriented groups, but showed significant differences across teams in their perceptions of the team and hospital environments. The task-oriented character of rehabilitation teams, team-specific characteristics, and discord in interprofessional relationships may need to be considered in studies of rehabilitation teams effectiveness.

Working memory contributes to elevated motor activity in adults with ADHD: an examination of the role of central executive and storage/rehearsal processes.

PubMed

Hudec, Kristen L; Alderson, R Matt; Kasper, Lisa J; Patros, Connor H G

2014-05-01

The relationship between working memory (WM) and objectively measured motor activity was examined in adults with ADHD and healthy controls (HCs). Thirty-five adults (ADHD = 20, HC = 15) were grouped using self-report and collateral-report measures in addition to a semistructured clinical interview. All participants completed control conditions with minimal WM demands, and separate phonological (PH) and visuospatial (VS) WM tasks with recall demands ranging from four to seven stimuli. The ADHD group exhibited significantly more motor activity relative to the HC group, and both groups exhibited greater activity during PH and VS WM tasks, relative to control conditions. Finally, the central executive (CE) and PH storage/rehearsal subsystems were associated with large-magnitude between-group differences in activity. Findings suggest that increased demands on WM, particularly the CE and PH storage/rehearsal, contribute to ADHD-related hyperactivity, though a portion of excessive motor activity in adults with ADHD may occur independently of WM demands.

Belief attribution despite verbal interference.

PubMed

Forgeot d'Arc, Baudouin; Ramus, Franck

2011-05-01

False-belief (FB) tasks have been widely used to study the ability of individuals to represent the content of their conspecifics' mental states (theory of mind). However, the cognitive processes involved are still poorly understood, and it remains particularly debated whether language and inner speech are necessary for the attribution of beliefs to other agents. We present a completely nonverbal paradigm consisting of silent animated cartoons in five closely related conditions, systematically teasing apart different aspects of scene analysis and allowing the assessment of the attribution of beliefs, goals, and physical causation. In order to test the role of language in belief attribution, we used verbal shadowing as a dual task to inhibit inner speech. Data on 58 healthy adults indicate that verbal interference decreases overall performance, but has no specific effect on belief attribution. Participants remained able to attribute beliefs despite heavy concurrent demands on their verbal abilities. Our results are most consistent with the hypothesis that belief attribution is independent from inner speech.

Short-Term and Working Memory Impairments in Early-Implanted, Long-Term Cochlear Implant Users Are Independent of Audibility and Speech Production

PubMed Central

AuBuchon, Angela M.; Pisoni, David B.; Kronenberger, William G.

2015-01-01

OBJECTIVES Determine if early-implanted, long-term cochlear implant (CI) users display delays in verbal short-term and working memory capacity when processes related to audibility and speech production are eliminated. DESIGN Twenty-three long-term CI users and 23 normal-hearing controls each completed forward and backward digit span tasks under testing conditions which differed in presentation modality (auditory or visual) and response output (spoken recall or manual pointing). RESULTS Normal-hearing controls reproduced more lists of digits than the CI users, even when the test items were presented visually and the responses were made manually via touchscreen response. CONCLUSIONS Short-term and working memory delays observed in CI users are not due to greater demands from peripheral sensory processes such as audibility or from overt speech-motor planning and response output organization. Instead, CI users are less efficient at encoding and maintaining phonological representations in verbal short-term memory utilizing phonological and linguistic strategies during memory tasks. PMID:26496666

Multiple-object permanence tracking: limitation in maintenance and transformation of perceptual objects.

PubMed

Saiki, Jun

2002-01-01

Research on change blindness and transsaccadic memory revealed that a limited amount of information is retained across visual disruptions in visual working memory. It has been proposed that visual working memory can hold four to five coherent object representations. To investigate their maintenance and transformation in dynamic situations, I devised an experimental paradigm called multiple-object permanence tracking (MOPT) that measures memory for multiple feature-location bindings in dynamic situations. Observers were asked to detect any color switch in the middle of a regular rotation of a pattern with multiple colored disks behind an occluder. The color-switch detection performance dramatically declined as the pattern rotation velocity increased, and this effect of object motion was independent of the number of targets. The MOPT task with various shapes and colors showed that color-shape conjunctions are not available in the MOPT task. These results suggest that even completely predictable motion severely reduces our capacity of object representations, from four to only one or two.

Short-Term and Working Memory Impairments in Early-Implanted, Long-Term Cochlear Implant Users Are Independent of Audibility and Speech Production.

PubMed

AuBuchon, Angela M; Pisoni, David B; Kronenberger, William G

2015-01-01

To determine whether early-implanted, long-term cochlear implant (CI) users display delays in verbal short-term and working memory capacity when processes related to audibility and speech production are eliminated. Twenty-three long-term CI users and 23 normal-hearing controls each completed forward and backward digit span tasks under testing conditions that differed in presentation modality (auditory or visual) and response output (spoken recall or manual pointing). Normal-hearing controls reproduced more lists of digits than the CI users, even when the test items were presented visually and the responses were made manually via touchscreen response. Short-term and working memory delays observed in CI users are not due to greater demands from peripheral sensory processes such as audibility or from overt speech-motor planning and response output organization. Instead, CI users are less efficient at encoding and maintaining phonological representations in verbal short-term memory using phonological and linguistic strategies during memory tasks.

Health literacy and task environment influence parents' burden for data entry on child-specific health information: randomized controlled trial.

PubMed

Porter, Stephen C; Guo, Chao-Yu; Bacic, Janine; Chan, Eugenia

2011-01-26

Health care systems increasingly rely on patients' data entry efforts to organize and assist in care delivery through health information exchange. We sought to determine (1) the variation in burden imposed on parents by data entry efforts across paper-based and computer-based environments, and (2) the impact, if any, of parents' health literacy on the task burden. We completed a randomized controlled trial of parent-completed data entry tasks. Parents of children with attention deficit hyperactivity disorder (ADHD) were randomized based on the Test of Functional Health Literacy in Adults (TOFHLA) to either a paper-based or computer-based environment for entry of health information on their children. The primary outcome was the National Aeronautics and Space Administration Task Load Index (TLX) total weighted score. We screened 271 parents: 194 (71.6%) were eligible, and 180 of these (92.8%) constituted the study cohort. We analyzed 90 participants from each arm. Parents who completed information tasks on paper reported a higher task burden than those who worked in the computer environment: mean (SD) TLX scores were 22.8 (20.6) for paper and 16.3 (16.1) for computer. Assignment to the paper environment conferred a significant risk of higher task burden (F(1,178) = 4.05, P = .046). Adequate literacy was associated with lower task burden (decrease in burden score of 1.15 SD, P = .003). After adjusting for relevant child and parent factors, parents' TOFHLA score (beta = -.02, P = .02) and task environment (beta = .31, P = .03) remained significantly associated with task burden. A tailored computer-based environment provided an improved task experience for data entry compared to the same tasks completed on paper. Health literacy was inversely related to task burden.

Cue-Independent Task-Specific Representations in Task Switching: Evidence from Backward Inhibition

ERIC Educational Resources Information Center

Altmann, Erik M.

2007-01-01

The compound-cue model of cognitive control in task switching explains switch cost in terms of a switch of task cues rather than of a switch of tasks. The present study asked whether the model generalizes to Lag 2 repetition cost (also known as backward inhibition), a related effect in which the switch from B to A in ABA task sequences is costlier…

The remains of the trial: goal-determined inter-trial suppression of selective attention.

PubMed

Lleras, Alejandro; Levinthal, Brian R; Kawahara, Jun

2009-01-01

When an observer is searching through the environment for a target, what are the consequences of not finding a target in a given environment? We examine this issue in detail and propose that the visual system systematically tags environmental information during a search, in an effort to improve performance in future search events. Information that led to search successes is positively tagged, so as to favor future deployments of attention toward that type of information, whereas information that led to search failures is negatively tagged, so as to discourage future deployments of attention toward such failed information. To study this, we use an oddball-search task, where participants search for one item that differs from all others along one feature or belongs to a different visual category, from the other stimuli in the display. We find that when participants perform oddball-search tasks, the absence of a target delays identification of future targets containing the feature or category that was shared by all distractors in the target-absent trial. We interpret this effect as reflecting an implicit assessment of performance: target-absent trials can be viewed as processing "failures" insofar as they do not provide the visual system with the information needed to complete the task. Here, we study the goal-oriented nature of this bias in three ways. First, we show that the direction of the bias is determined by the experimental task. Second, we show that the effect is independent of the mode of presentation of stimuli: it happens with both serial and simultaneous stimuli presentation. Third, we show that, when using categorically defined oddballs as the search stimuli (find the face among houses or vice versa), the bias generalizes to unseen members of the "failed" category. Together, these findings support the idea that this inter-trial attentional biases arise from high-level, task-constrained, implicit assessments of performance, involving categorical associations between classes of stimuli and behavioral outcomes (success/failure), which are independent of attentional modality (temporal vs. spatial attention).

Theory of mind in SLI revisited: links with syntax, comparisons with ASD.

PubMed

Durrleman, Stephanie; Burnel, Morgane; Reboul, Anne

2017-11-01

According to the linguistic determinism approach, knowledge of sentential complements such as: John says that the earth is flat plays a crucial role in theory of mind (ToM) development by providing a means to represent explicitly people's mental attitudes and beliefs. This approach predicts that mastery of complements determines successful belief reasoning across explicit ToM tasks, even low-verbal ones, and across populations. (1) To investigate the link between a low-verbal ToM-task and complements in Specific Language Impairment (SLI), (2) To determine whether this population shows similar ToM performance to that of children with Autism Spectrum Disorder (ASD) or those with Typical Development (TD) once these groups are matched on competency for complements, (3) To explore whether complements conveying a falsehood without jeopardizing the veracity of the entire sentence, such as complements of verbs of communication, are more crucial for belief attribution than complements which do not have this property, namely complements of verbs of perception, (?John sees that the earth is flat). Children with SLI (n = 20), with ASD (n = 34) and TD (n = 30) completed sentence-picture-matching tasks assessing complementation with communication and perception verbs, as well as a picture-sequencing task assessing ToM. Children were furthermore evaluated for general grammatical and lexical abilities and non-verbal IQ. Results reveal that competency on complements relates to ToM performance with a low-verbal task in SLI, and that SLI, ASD and TD groups of equivalent performance on complements also perform similarly for ToM. Results further suggest that complements with an independent truth-value are the only ones to show a significant relation to ToM performance after teasing out the impact of non-verbal reasoning. This study suggests that clinical groups of different aetiologies as well as TD children perform comparably for ToM once they have similar complementation skills. Findings further highlight that specific types of complements, namely those with an independent truth value, relate in a special way to mentalizing. Future work should determine whether these specific structures could be effective in ToM remediation programmes. © 2017 Royal College of Speech and Language Therapists.

KENNEDY SPACE CENTER, FLA. - In the Columbia Debris Hangar, Shuttle Launch Director Mike Leinbach answers questions from the Stafford-Covey Return to Flight Task Group (SCTG). Chairing the task group are Richard O. Covey (fifth from left), former Space Shuttle commander, and Thomas P. Stafford, Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

NASA Image and Video Library

2003-08-05

KENNEDY SPACE CENTER, FLA. - In the Columbia Debris Hangar, Shuttle Launch Director Mike Leinbach answers questions from the Stafford-Covey Return to Flight Task Group (SCTG). Chairing the task group are Richard O. Covey (fifth from left), former Space Shuttle commander, and Thomas P. Stafford, Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

KENNEDY SPACE CENTER, FLA. - In the Columbia Debris Hangar, Shuttle Launch Director Mike Leinbach (left) talks to members of the Stafford-Covey Return to Flight Task Group (SCTG) about reconstruction efforts. Chairing the task group are Richard O. Covey (second from right), former Space Shuttle commander, and Thomas P. Stafford, Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

NASA Image and Video Library

2003-08-05

KENNEDY SPACE CENTER, FLA. - In the Columbia Debris Hangar, Shuttle Launch Director Mike Leinbach (left) talks to members of the Stafford-Covey Return to Flight Task Group (SCTG) about reconstruction efforts. Chairing the task group are Richard O. Covey (second from right), former Space Shuttle commander, and Thomas P. Stafford, Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

Assessment of planning abilities in individuals with mild cognitive impairment using an open-ended problem-solving task.

PubMed

Sanders, Chad; Low, Christina; Schmitter-Edgecombe, Maureen

2014-01-01

There is currently limited research evaluating planning abilities, a core subcomponent of executive functioning, in individuals with mild cognitive impairment (MCI). In the present study, we utilized the "Amap Task," an open-ended problem-solving task, to separately evaluate the formulation and execution components of planning ability in individuals with MCI. Thirty-seven cognitively healthy older adults and 37 individuals with MCI used a map layout of a university apartment to develop and write out a strategy (formulation stage) to successfully complete a list of tasks (e.g., retrieve and fill a water pitcher before placing it in the refrigerator). Subsequently, participants carried out the tasks in the apartment with the aid of their formulated plan (execution stage). MCI participants performed more poorly than older adult (OA) controls during both the formulation and execution stages on measures of task accuracy and task efficiency. However, both groups were able to adjust and improve task accuracy and efficiency from formulation to task execution. Finally, MCI participants took significantly longer to complete the task and adhered less to their formulated plans during task completion. Using an open-ended problem-solving task, the findings revealed that individuals with MCI experienced difficulties with both the formulation and execution components of planning. Like controls, participants with MCI were able to successfully modify their plan online, improving their performance from task formulation to task execution.

Comparing surgical experience with performance on a sinus surgery simulator.

PubMed

Diment, Laura E; Ruthenbeck, Greg S; Dharmawardana, Nuwan; Carney, A Simon; Woods, Charmaine M; Ooi, Eng H; Reynolds, Karen J

2016-12-01

This study evaluates whether surgical experience influences technical competence using the Flinders sinus surgery simulator, a virtual environment designed to teach nasal endoscopic surgical skills. Ten experienced sinus surgeons (five consultants and five registrars) and 14 novices (seven resident medical officers and seven interns/medical students) completed three simulation tasks using haptic controllers. Task 1 required navigation of the sinuses and identification of six anatomical landmarks, Task 2 required removal of unhealthy tissue while preserving healthy tissue and Task 3 entailed backbiting within pre-set lines on the uncinate process and microdebriding tissue between the cuts. Novices were compared with experts on a range of measures, using Mann-Whitney U -tests. Novices took longer on all tasks (Task 1: 278%, P < 0.005; Task 2: 112%, P < 0.005; Task 3: 72%, P < 0.005). In Task 1, novices' instruments travelled further than experts' (379%, P < 0.005), and provided greater maximum force (12%, P < 0.05). In Tasks 2 and 3 novices performed more cutting movements to remove the tissue (Task 2: 1500%, P < 0.005; Task 3: 72%, P < 0.005). Experts also completed more of Task 3 (66%, P < 0.05). The study demonstrated the Flinders sinus simulator's construct validity, differentiating between experts and novices with respect to procedure time, instrument distance travelled and number of cutting motions to complete the task. © 2015 Royal Australasian College of Surgeons.

Using Technological Advances to Improve Surgery Curriculum: Experience With a Mobile Application.

PubMed

Green, Courtney A; Kim, Edward H; O'Sullivan, Patricia S; Chern, Hueylan

2018-01-31

Our previous home-video basic surgical skills curriculum required substantial faculty time and resources, and was limited by delayed feedback and technical difficulties. Consequently, we integrated that curriculum with a mobile application platform. Our purpose is to describe this application and learner satisfaction. The mobile platform incorporates a patented pedagogical design based on Ericsson's deliberate practice and Bandura's social learning theory. Instructors built step-wise skills modules. During the challenge phase, learners watched a video of surgical tasks completed by experts and uploaded a video of themselves performing the same task. In the Peer Review phase, they used a grading rubric to provide feedback. In the Recap stage, learners received individual feedback and could review their own videos. Two groups of learners, graduating medical students and matriculating surgical residents, participated in this independent learning platform, along with 2 to 4 laboratory sessions, and completed a survey about their experience. Survey responses were summarized descriptively and comments analyzed using content analysis. Fifty learners submitted videos of assigned tasks and completed peer reviews. Learners reported positive experiences specifically for the Peer Review Stage, structured home practice, ease of mobile access to submit and review videos, and ongoing immediate feedback. Over half of the learners reported spending at least 10 to 30 minute practicing skills before recording their videos and over 80% rerecorded at least 2 times before submission. Content analysis revealed learners engaged with the educational concepts designed into the platform. Learners easily used and were satisfied with a mobile-technology teaching platform that maintained the fundamental content, educational theories, and organizational structure of our previously effective surgical skills curriculum. Prior challenges were directly addressed through the mobile application's ease of use, support of deliberate practice, and improved timeliness of feedback. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Premise and Inference Memory as a Function of Age and Context.

ERIC Educational Resources Information Center

Wagner, Michael; Rohwer, William D., Jr.

A sentence completion task was used to investigate age differences in childrens' ability or inclination to invoke premises and inferences during prose processing, tasks which (according to the constructive hypothesis) adults typically perform. A pilot study confirmed that the sentence completion task was preferable to the recognition paradigm,…

Towards a hemodynamic BCI using transcranial Doppler without user-specific training data

NASA Astrophysics Data System (ADS)

Aleem, Idris; Chau, Tom

2013-02-01

Transcranial Doppler (TCD) was recently introduced as a new brain-computer interface (BCI) modality for detecting task-induced hemispheric lateralization. To date, single-trial discrimination between a lateralized mental activity and a rest state has been demonstrated with long (45 s) activation time periods. However, the possibility of detecting successive activations in a user-independent framework (i.e. without training data from the user) remains an open question. Objective. The objective of this research was to assess TCD-based detection of lateralized mental activity with a user-independent classifier. In so doing, we also investigated the accuracy of detecting successive lateralizations. Approach. TCD data from 18 participants were collected during verbal fluency, mental rotation tasks and baseline counting tasks. Linear discriminant analysis and a set of four time-domain features were used to classify successive left and right brain activations. Main results. In a user-independent framework, accuracies up to 74.6 ± 12.6% were achieved using training data from a single participant, and lateralization task durations of 18 s. Significance. Subject-independent, algorithmic classification of TCD signals corresponding to successive brain lateralization may be a feasible paradigm for TCD-BCI design.

Construction of a Urologic Robotic Surgery Training Curriculum: How Many Simulator Sessions Are Required for Residents to Achieve Proficiency?

PubMed

Wiener, Scott; Haddock, Peter; Shichman, Steven; Dorin, Ryan

2015-11-01

To define the time needed by urology residents to attain proficiency in computer-aided robotic surgery to aid in the refinement of a robotic surgery simulation curriculum. We undertook a retrospective review of robotic skills training data acquired during January 2012 to December 2014 from junior (postgraduate year [PGY] 2-3) and senior (PGY4-5) urology residents using the da Vinci Skills Simulator. We determined the number of training sessions attended and the level of proficiency achieved by junior and senior residents in attempting 11 basic or 6 advanced tasks, respectively. Junior residents successfully completed 9.9 ± 1.8 tasks, with 62.5% completing all 11 basic tasks. The maximal cumulative success rate of junior residents completing basic tasks was 89.8%, which was achieved within 7.0 ± 1.5 hours of training. Of senior residents, 75% successfully completed all six advanced tasks. Senior residents attended 6.3 ± 3.5 hours of training during which 5.1 ± 1.6 tasks were completed. The maximal cumulative success rate of senior residents completing advanced tasks was 85.4%. When designing and implementing an effective robotic surgical training curriculum, an allocation of 10 hours of training may be optimal to allow junior and senior residents to achieve an acceptable level of surgical proficiency in basic and advanced robotic surgical skills, respectively. These data help guide the design and scheduling of a residents training curriculum within the time constraints of a resident's workload.

Mind wandering and retrieval from episodic memory: a pilot event-related potential study.

PubMed

Riby, Leigh Martin; Smallwood, Jonathan; Gunn, Valerie P

2008-06-01

The present study investigated the effects of mind wandering (task-unrelated thought) on the subcomponents of episodic memory as reflected by event-related potentials (ERPs). Specifically, individual differences in the pattern of ERP episodic 'old/new' effects (left-parietal, right-frontal and central-negativity effects) were examined across groups of participants experiencing either high or low frequencies of task-unrelated thought during encoding. Twenty participants studied lists of words and line drawings in one of two contexts (red versus green coloured boxes). At test, participants discriminated between target (old words or line drawings presented in one colour) and nontargets (old items from the other colour and new items). On completion of the memory task, participants completed the 'thinking' component of the Dundee Stress State Questionnaire to provide a retrospective measure of task-unrelated thought. Behavioural data indicated that irrespective of the presence of task-unrelated thought, participants were able to complete the memory task equally well. However, an analysis of ERPs across High and Low task-unrelated thought groups revealed differences in retrieval strategy. Those individuals with infrequent episodes of task-unrelated thought at study used a 'pure' recollection strategy (left-parietal effect only). Conversely, those participants experiencing frequent episodes of task-unrelated thought were unable to recollect the stimuli with ease, as indexed by a diminished parietal effect. As a consequence, these participants employed additional strategic processes for task completion, as indexed by an elevated amplitude of central negativity effects. These data are consistent with the decoupling hypothesis of mind wandering which suggests impaired recollection when attention becomes directed away from the task.

Is negative self-referent bias an endophenotype for depression? An fMRI study of emotional self-referent words in twins at high vs. low risk of depression.

PubMed

Miskowiak, K W; Larsen, J E; Harmer, C J; Siebner, H R; Kessing, L V; Macoveanu, J; Vinberg, M

2018-01-15

Negative cognitive bias and aberrant neural processing of self-referent emotional words seem to be trait-marks of depression. However, it is unclear whether these neurocognitive changes are present in unaffected first-degree relatives and constitute an illness endophenotype. Fifty-three healthy, never-depressed monozygotic or dizygotic twins with a co-twin history of depression (high-risk group: n = 26) or no first-degree family history of depression (low-risk group: n = 27) underwent neurocognitive testing and functional magnetic imaging (fMRI) as part of a follow-up cohort study. Participants performed a self-referent emotional word categorisation task and free word recall task followed by a recognition task during fMRI. Participants also completed questionnaires assessing mood, personality traits and coping strategies. High-risk and low-risk twins (age, mean ± SD: 40 ± 11) were well-balanced for demographic variables, mood, coping and neuroticism. High-risk twins showed lower accuracy during self-referent categorisation of emotional words independent of valence and more false recollections of negative words than low-risk twins during free recall. Functional MRI yielded no differences between high-risk and low-risk twins in retrieval-specific neural activity for positive or negative words or during the recognition of negative versus positive words within the hippocampus or prefrontal cortex. The subtle display of negative recall bias is consistent with the hypothesis that self-referent negative memory bias is an endophenotype for depression. High-risk twins' lower categorisation accuracy adds to the evidence for valence-independent cognitive deficits in individuals at familial risk for depression. Copyright © 2017 Elsevier B.V. All rights reserved.

A Metacognitive model of procrastination.

PubMed

Fernie, Bruce A; Bharucha, Zinnia; Nikčević, Ana V; Marino, Claudia; Spada, Marcantonio M

2017-03-01

procrastination refers to the delay or postponement of task or decision-making initiation or completion and is often conceptualised as a failure of self-regulation. Recent research has suggested that metacognitions play a role in procrastination and that unintentional procrastination (UP), as opposed to intentional procrastination (IP), may be the most problematic form of this behaviour. We aimed to test a metacognitive model of procrastination that was grounded in the Self-Regulatory Executive Function model. a convenience sample of 400 participants were recruited and completed (at least partially) a battery of online questionnaires that measured IP and UP, metacognitions about procrastination, depression, and Cognitive Attentional Syndrome (CAS) configurations. Initially, we tested series of hypotheses to establish the relationships between the experimental variables and to test whether CAS configurations would independently predict UP when controlling for age, depression, IP, metacognitions about procrastination, and whether an individual reported that they had been diagnosed with a psychiatric disorder. CAS configurations, depression, and metacognitions independently predicted UP. Additionally, path analysis revealed that the study data was an excellent fit to the proposed metacognitive model of procrastination. the study is cross-sectional. the metacognitive model of procrastination presented in this paper can be used to generate novel interventions to treat this problematic behaviour. Copyright © 2016 Elsevier B.V. All rights reserved.

The impact of storage on processing: how is information maintained in working memory?

PubMed

Vergauwe, Evie; Camos, Valérie; Barrouillet, Pierre

2014-07-01

Working memory is typically defined as a system devoted to the simultaneous maintenance and processing of information. However, the interplay between these 2 functions is still a matter of debate in the literature, with views ranging from complete independence to complete dependence. The time-based resource-sharing model assumes that a central bottleneck constrains the 2 functions to alternate in such a way that maintenance activities postpone concurrent processing, with each additional piece of information to be maintained resulting in an additional postponement. Using different kinds of memoranda, we examined in a series of 7 experiments the effect of increasing memory load on different processing tasks. The results reveal that, insofar as attention is needed for maintenance, processing times linearly increase at a rate of about 50 ms per verbal or visuospatial memory item, suggesting a very fast refresh rate in working memory. Our results also show an asymmetry between verbal and spatial information, in that spatial information can solely rely on attention for its maintenance while verbal information can also rely on a domain-specific maintenance mechanism independent from attention. The implications for the functioning of working memory are discussed, with a specific focus on how information is maintained in working memory. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Predictive Factors of Household Task Participation in Brazilian Children and Adolescents.

PubMed

Drummond, Adriana de França; Gomes, Ana Maria Rabelo; Coster, Wendy J; Mancini, Marisa Cotta

2015-04-01

Home environment is an important setting for child participation. This study investigated the participation of Brazilian children and adolescents in household self-care (SC) and family-care (FC) tasks. Interviews were conducted with 109 caregivers of children and adolescents ages 6 to 14 years residing in Belo Horizonte (Brazil). Multiple regression models revealed that a greater number of FC tasks were performed by children and adolescents (R2 = .23) from families who did not have a housekeeper and those in which the mothers did not work outside of the home; children and adolescents from this subgroup also received less assistance from the caregivers (R2 = .21) and showed greater independence in task performance (R2 = .20). On average, Brazilian children and adolescents participate in about half of the SC and 25% the FC household tasks. Factors related to family structure and child's age were associated with task performance, caregiver assistance, and child and adolescent independence in household tasks.

Integrated consensus-based frameworks for unmanned vehicle routing and targeting assignment

NASA Astrophysics Data System (ADS)

Barnawi, Waleed T.

Unmanned aerial vehicles (UAVs) are increasingly deployed in complex and dynamic environments to perform multiple tasks cooperatively with other UAVs that contribute to overarching mission effectiveness. Studies by the Department of Defense (DoD) indicate future operations may include anti-access/area-denial (A2AD) environments which limit human teleoperator decision-making and control. This research addresses the problem of decentralized vehicle re-routing and task reassignments through consensus-based UAV decision-making. An Integrated Consensus-Based Framework (ICF) is formulated as a solution to the combined single task assignment problem and vehicle routing problem. The multiple assignment and vehicle routing problem is solved with the Integrated Consensus-Based Bundle Framework (ICBF). The frameworks are hierarchically decomposed into two levels. The bottom layer utilizes the renowned Dijkstra's Algorithm. The top layer addresses task assignment with two methods. The single assignment approach is called the Caravan Auction Algorithm (CarA) Algorithm. This technique extends the Consensus-Based Auction Algorithm (CBAA) to provide awareness for task completion by agents and adopt abandoned tasks. The multiple assignment approach called the Caravan Auction Bundle Algorithm (CarAB) extends the Consensus-Based Bundle Algorithm (CBBA) by providing awareness for lost resources, prioritizing remaining tasks, and adopting abandoned tasks. Research questions are investigated regarding the novelty and performance of the proposed frameworks. Conclusions regarding the research questions will be provided through hypothesis testing. Monte Carlo simulations will provide evidence to support conclusions regarding the research hypotheses for the proposed frameworks. The approach provided in this research addresses current and future military operations for unmanned aerial vehicles. However, the general framework implied by the proposed research is adaptable to any unmanned vehicle. Civil applications that involve missions where human observability would be limited could benefit from the independent UAV task assignment, such as exploration and fire surveillance are also notable uses for this approach.

Assessment of Unconstrained Cerebrovascular Reactivity Marker for Large Age-Range fMRI Studies

PubMed Central

Kannurpatti, Sridhar S.; Motes, Michael A.; Biswal, Bharat B.; Rypma, Bart

2014-01-01

Breath hold (BH), a commonly used task to measure cerebrovascular reactivity (CVR) in fMRI studies varies in outcome among individuals due to subject-physiology and/or BH-inspiration/expiration differences (i.e., performance). In prior age-related fMRI studies, smaller task-related BOLD response variability is observed among younger than older individuals. Also, a linear CVR versus task relationship exists in younger individuals which maybe useful to test the accuracy of CVR responses in older groups. Hence we hypothesized that subject-related physiological and/or BH differences, if present, may compromise CVR versus task linearity in older individuals. To test the hypothesis, empirical BH versus task relationships from motor and cognitive areas were obtained in younger (mean age = 26 years) and older (mean age = 58 years) human subjects. BH versus task linearity was observed only in the younger group, confirming our hypothesis. Further analysis indicated BH responses and its variability to be similar in both younger and older groups, suggesting that BH may not accurately represent CVR in a large age range. Using the resting state fluctuation of amplitude (RSFA) as an unconstrained alternative to BH, subject-wise correspondence between BH and RSFA was tested. Correlation between BH versus RSFA was significant within the motor but was not significant in the cognitive areas in the younger and was completely disrupted in both areas in the older subjects indicating that BH responses are constrained by subject-related physiology and/or performance-related differences. Contrasting BH to task, RSFA-task relationships were independent of age accompanied by age-related increases in CVR variability as measured by RSFA, not observed with BH. Together the results obtained indicate that RSFA accurately represents CVR in any age range avoiding multiple and yet unknown physiologic and task-related pitfalls of BH. PMID:24551151

Contributions of Hippocampus and Striatum to Memory-Guided Behavior Depend on Past Experience

PubMed Central

2016-01-01

The hippocampal and striatal memory systems are thought to operate independently and in parallel in supporting cognitive memory and habits, respectively. Much of the evidence for this principle comes from double dissociation data, in which damage to brain structure A causes deficits in Task 1 but not Task 2, whereas damage to structure B produces the reverse pattern of effects. Typically, animals are explicitly trained in one task. Here, we investigated whether this principle continues to hold when animals concurrently learn two types of tasks. Rats were trained on a plus maze in either a spatial navigation or a cue–response task (sequential training), whereas a third set of rats acquired both (concurrent training). Subsequently, the rats underwent either sham surgery or neurotoxic lesions of the hippocampus (HPC), medial dorsal striatum (DSM), or lateral dorsal striatum (DSL), followed by retention testing. Finally, rats in the sequential training condition also acquired the novel “other” task. When rats learned one task, HPC and DSL selectively supported spatial navigation and cue response, respectively. However, when rats learned both tasks, HPC and DSL additionally supported the behavior incongruent with the processing style of the corresponding memory system. Thus, in certain conditions, the hippocampal and striatal memory systems can operate cooperatively and in synergism. DSM significantly contributed to performance regardless of task or training procedure. Experience with the cue–response task facilitated subsequent spatial learning, whereas experience with spatial navigation delayed both concurrent and subsequent response learning. These findings suggest that there are multiple operational principles that govern memory networks. SIGNIFICANCE STATEMENT Currently, we distinguish among several types of memories, each supported by a distinct neural circuit. The memory systems are thought to operate independently and in parallel. Here, we demonstrate that the hippocampus and the dorsal striatum memory systems operate independently and in parallel when rats learn one type of task at a time, but interact cooperatively and in synergism when rats concurrently learn two types of tasks. Furthermore, new learning is modulated by past experiences. These results can be explained by a model in which independent and parallel information processing that occurs in the separate memory-related neural circuits is supplemented by information transfer between the memory systems at the level of the cortex. PMID:27307234

Contributions of Hippocampus and Striatum to Memory-Guided Behavior Depend on Past Experience.

PubMed

Ferbinteanu, Janina

2016-06-15

The hippocampal and striatal memory systems are thought to operate independently and in parallel in supporting cognitive memory and habits, respectively. Much of the evidence for this principle comes from double dissociation data, in which damage to brain structure A causes deficits in Task 1 but not Task 2, whereas damage to structure B produces the reverse pattern of effects. Typically, animals are explicitly trained in one task. Here, we investigated whether this principle continues to hold when animals concurrently learn two types of tasks. Rats were trained on a plus maze in either a spatial navigation or a cue-response task (sequential training), whereas a third set of rats acquired both (concurrent training). Subsequently, the rats underwent either sham surgery or neurotoxic lesions of the hippocampus (HPC), medial dorsal striatum (DSM), or lateral dorsal striatum (DSL), followed by retention testing. Finally, rats in the sequential training condition also acquired the novel "other" task. When rats learned one task, HPC and DSL selectively supported spatial navigation and cue response, respectively. However, when rats learned both tasks, HPC and DSL additionally supported the behavior incongruent with the processing style of the corresponding memory system. Thus, in certain conditions, the hippocampal and striatal memory systems can operate cooperatively and in synergism. DSM significantly contributed to performance regardless of task or training procedure. Experience with the cue-response task facilitated subsequent spatial learning, whereas experience with spatial navigation delayed both concurrent and subsequent response learning. These findings suggest that there are multiple operational principles that govern memory networks. Currently, we distinguish among several types of memories, each supported by a distinct neural circuit. The memory systems are thought to operate independently and in parallel. Here, we demonstrate that the hippocampus and the dorsal striatum memory systems operate independently and in parallel when rats learn one type of task at a time, but interact cooperatively and in synergism when rats concurrently learn two types of tasks. Furthermore, new learning is modulated by past experiences. These results can be explained by a model in which independent and parallel information processing that occurs in the separate memory-related neural circuits is supplemented by information transfer between the memory systems at the level of the cortex. Copyright © 2016 the authors 0270-6474/16/366459-12$15.00/0.

Lower Klickitat Riparian and In-channel Habitat Restoration Project; Klickitat Watershed Enhancement, Annual Report 2002-2003.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Conley, Will

2004-01-01

The overall goal of the Klickitat Watershed Enhancement Project (KWEP) is to restore watershed health to aid recovery of salmonid stocks in the Klickitat subbasin. An emphasis is placed on restoration and protection of stream reaches and watersheds supporting native anadromous fish production, particularly steelhead (Oncorhyncus mykiss; ESA- listed as 'Threatened' within the Mid-Columbia ESU) and spring Chinook (O. tshawytscha). Habitat restoration activities in the Klickitat subbasin augment goals and objectives of the Yakima Klickitat Fisheries Project (YKFP), NPPC Fish and Wildlife Program, Klickitat Subbasin Summary and the NMFS Biological Opinion (All-H paper). Work is conducted to enhance instream andmore » contributing upland habitat to facilitate increased natural production potential for native salmonid stocks. Efforts in the Klickitat Subbasin fall into two main categories: (1) identification and prioritization of sites for protection and restoration activities, (2) implementation of protection and restoration measures. KWEP personnel also assist monitoring efforts of the YKFP Monitoring & Evaluation Project. During the September 2002-August 2003 reporting period, KWEP personnel continued efforts to address feedback from the August 2000 Provincial Review that indicated a need for better information management and development of geographic priorities by: (1) Assisting development of the Strategic Habitat Plan for the Klickitat Lead Entity (Task A3.1) and Klickitat steelhead EDT model (Task A4.1); (2) Improving the functionality of reference point, habitat unit, and large woody debris modules of the habitat database as well as addition of a temperature module (Tasks A1.1-1.2); (3) Continuing development and acquisition of GIS data (Task A1.3); (4) Ongoing data collection efforts to fill information gaps including streamflow, habitat, and temperature (Objectives C1 and C2); and (5) Completion of planning, field work, and hydrologic modeling associated with roads assessment in the White Creek watershed (Task A4.2). Significant milestones associated with restoration projects during the reporting period included: (1) Completion of the Surveyors Fish Creek Passage Enhancement project (Task B2.3); (2) Completion of interagency agreements for the Klickitat Meadows (Task B2.4) and Klickitat Mill (Task B2.10) projects; (3) Completion of topographic surveys for the Klickitat Meadows (Task B2.4), Klickitat River Meadows (Task B2.5), Trout Creek and Bear Creek culvert replacements (Task B2.7), and Snyder Swale II (Task B2.13) projects; (4) Completion of the Snyder Swale II - Phase 1 project (Task B2.13); (5) Completion of design, planning, and permitting for the Klickitat Mill project (Task B2.10) and initiation of construction; (6) Design for the Trout and Bear Creek culverts (B2.7) were brought to the 60% level; and (7) Completion of design work for the for the Klickitat Meadows (Task B2.4) and Klickitat River Meadows (Task B2.5) projects.« less

Sort-Mid tasks scheduling algorithm in grid computing.

PubMed

Reda, Naglaa M; Tawfik, A; Marzok, Mohamed A; Khamis, Soheir M

2015-11-01

Scheduling tasks on heterogeneous resources distributed over a grid computing system is an NP-complete problem. The main aim for several researchers is to develop variant scheduling algorithms for achieving optimality, and they have shown a good performance for tasks scheduling regarding resources selection. However, using of the full power of resources is still a challenge. In this paper, a new heuristic algorithm called Sort-Mid is proposed. It aims to maximizing the utilization and minimizing the makespan. The new strategy of Sort-Mid algorithm is to find appropriate resources. The base step is to get the average value via sorting list of completion time of each task. Then, the maximum average is obtained. Finally, the task has the maximum average is allocated to the machine that has the minimum completion time. The allocated task is deleted and then, these steps are repeated until all tasks are allocated. Experimental tests show that the proposed algorithm outperforms almost other algorithms in terms of resources utilization and makespan.

Sort-Mid tasks scheduling algorithm in grid computing

PubMed Central

Reda, Naglaa M.; Tawfik, A.; Marzok, Mohamed A.; Khamis, Soheir M.

2014-01-01

Scheduling tasks on heterogeneous resources distributed over a grid computing system is an NP-complete problem. The main aim for several researchers is to develop variant scheduling algorithms for achieving optimality, and they have shown a good performance for tasks scheduling regarding resources selection. However, using of the full power of resources is still a challenge. In this paper, a new heuristic algorithm called Sort-Mid is proposed. It aims to maximizing the utilization and minimizing the makespan. The new strategy of Sort-Mid algorithm is to find appropriate resources. The base step is to get the average value via sorting list of completion time of each task. Then, the maximum average is obtained. Finally, the task has the maximum average is allocated to the machine that has the minimum completion time. The allocated task is deleted and then, these steps are repeated until all tasks are allocated. Experimental tests show that the proposed algorithm outperforms almost other algorithms in terms of resources utilization and makespan. PMID:26644937

San Joaquin River Up-Stream DO TMDL Project Task 4: MonitoringStudy Interim Task Report #3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stringfellow, William; Borglin, Sharon; Dahlgren, Randy

2007-03-30

The purpose of the Dissolved Oxygen Total Maximum Daily LoadProject (DO TMDLProject) is to provide a comprehensive understanding ofthe sources and fate of oxygen consuming materials in the San JoaquinRiver (SJR) watershed between Channel Point and Lander Avenue (upstreamSJR). When completed, this study will provide the stakeholders anunderstanding of the baseline conditions of the basin, provide input foran allocation decision, and provide the stakeholders with a tool formeasuring the impact of any waterquality management program that may beimplemented as part of the DO TMDL process. Previous studies haveidentified algal biomass as the most significant oxygen-demandingsubstance in the DO TMDL Projectmore » study-area between of Channel Point andLander Ave onthe SJR. Other oxygen-demanding substances found in theupstream SJR include ammonia and organic carbon from sources other thanalgae. The DO TMDL Project study-area contains municipalities, dairies,wetlands, cattle ranching, irrigated agriculture, and industries thatcould potentially contribute biochemical oxygen demand (BOD) to the SJR.This study is designed to discriminate between algal BOD and othersources of BOD throughout the entire upstream SJR watershed. Algalbiomass is not a conserved substance, but grows and decays in the SJR;hence, characterization of oxygen-demanding substances in the SJR isinherently complicated and requires an integrated effort of extensivemonitoring, scientific study, and modeling. In order to achieve projectobjectives, project activities were divided into a number of Tasks withspecific goals and objectives. In this report, we present the results ofmonitoring and research conducted under Task 4 of the DO TMDL Project.The major objective of Task 4 is to collect sufficient hydrologic (flow)and water quality (WQ) data to characterize the loading of algae, otheroxygen-demanding materials, and nutrients fromindividual tributaries andsub-watersheds of the upstream SJR between Mossdale and Lander Avenue.This data is specifically being collected to provide data for the Task 6Modeling effort. Task 4 provides input and calibration data for flow andWQ modeling associated with the low DO problems in the SJR watershed,including modeling on the linkage among nutrients, algae, and low DO.Task 4 is providing a higher volume of high quality and coherent data tothe modeling team than was available in the past for the upstream SJR.The monitoring and research activities under Task 4 are integrated withthe Modeling effort (Task 6) and are not designed to be a stand aloneprogram. Although, the majority of analysis of the Task 4 data isoccurring as part of the Task 6 Modeling program, analysis of Task 4 dataindependently of the modeling effort is also an important component ofthe DO TMDL Project effort. In this report, we present the results ofmonitoring and research conducted under Task 4. The major purposes ofthis report are to 1) document activities undertaken as part of theDOTMDL Project; 2) organize electronic data for delivery to Stateagencies, stakeholders and principal investigators (cooperators) on theDO TMDL Project; 3) provide a summary analysis of the data for referenceand to assist stakeholders in planning watershed activities inresponse tothe DO TMDL requirements; and 5) provide a preliminary scientificinterpretation independently of the Task 6 Modeling effort. Due to theextensive scope of theTask 4 portion of the DO TMDL Project, the Task 4March 2007 Interim Report is divided into a numbers of chapters andassociated appendixes designed to be able to stand1-3 independently ofeach other. The purpose of this chapter is to provide an overview of Task4 data collection and to explain the structure of the overallreport.« less

A temporary deficiency in self-control: Can heightened motivation overcome this effect?

PubMed

Kelly, Claire L; Crawford, Trevor J; Gowen, Emma; Richardson, Kelly; Sünram-Lea, Sandra I

2017-05-01

Self-control is important for everyday life and involves behavioral regulation. Self-control requires effort, and when completing two successive self-control tasks, there is typically a temporary drop in performance in the second task. High self-reported motivation and being made self-aware somewhat counteract this effect-with the result that performance in the second task is enhanced. The current study explored the relationship between self-awareness and motivation on sequential self-control task performance. Before employing self-control in an antisaccade task, participants initially applied self-control in an incongruent Stroop task or completed a control task. After the Stroop task, participants unscrambled sentences that primed self-awareness (each started with the word "I") or unscrambled neutral sentences. Motivation was measured after the antisaccade task. Findings revealed that, after exerting self-control in the incongruent Stroop task, motivation predicted erroneous responses in the antisaccade task for those that unscrambled neutral sentences, and high motivation led to fewer errors. Those primed with self-awareness were somewhat more motivated overall, but motivation did not significantly predict antisaccade performance. Supporting the resource allocation account, if one was motivated-intrinsically or via the manipulation of self-awareness-resources were allocated to both tasks leading to the successful completion of two sequential self-control tasks. © 2017 The Authors. Psychophysiology published by Wiley Periodicals, Inc. on behalf of Society for Psychophysiological Research.

Task by stimulus interactions in brain responses during Chinese character processing.

PubMed

Yang, Jianfeng; Wang, Xiaojuan; Shu, Hua; Zevin, Jason D

2012-04-02

In the visual word recognition literature, it is well understood that various stimulus effects interact with behavioral task. For example, effects of word frequency are exaggerated and effects of spelling-to-sound regularity are reduced in the lexical decision task, relative to reading aloud. Neuroimaging studies of reading often examine effects of task and stimulus properties on brain activity independently, but potential interactions between task demands and stimulus effects have not been extensively explored. To address this issue, we conducted lexical decision and symbol detection tasks using stimuli that varied parametrically in their word-likeness, and tested for task by stimulus class interactions. Interactions were found throughout the reading system, such that stimulus selectivity was observed during the lexical decision task, but not during the symbol detection task. Further, the pattern of stimulus selectivity was directly related to task difficulty, so that the strongest brain activity was observed to the most word-like stimuli that required "no" responses, whereas brain activity to words, which elicit rapid and accurate "yes" responses were relatively weak. This is in line with models that argue for task-dependent specialization of brain regions, and contrasts with the notion of task-independent stimulus selectivity in the reading system. Copyright © 2012 Elsevier Inc. All rights reserved.

Applied Meteorology Unit (AMU) Quarterly Report - Fourth Quarter FY-10

NASA Technical Reports Server (NTRS)

Bauman, William; Crawford, Winifred; Barrett, Joe; Watson, Leela; Wheeler, Mark

2010-01-01

Three AMU tasks were completed in this Quarter, each resulting in a forecast tool now being used in operations and a final report documenting how the work was done. AMU personnel completed the following tasks (1) Phase II of the Peak Wind Tool for General Forecasting task by delivering an improved wind forecasting tool to operations and providing training on its use; (2) a graphical user interface (GUI) she updated with new scripts to complete the ADAS Update and Maintainability task, and delivered the scripts to the Spaceflight Meteorology Group on Johnson Space Center, Texas and National Weather Service in Melbourne, Fla.; and (3) the Verify MesoNAM Performance task after we created and delivered a GUI that forecasters will use to determine the performance of the operational MesoNAM weather model forecast.

Completeness and overlap in open access systems: Search engines, aggregate institutional repositories and physics-related open sources

PubMed Central

Wu, Tai-luan; Tseng, Ling-li

2017-01-01

This study examines the completeness and overlap of coverage in physics of six open access scholarly communication systems, including two search engines (Google Scholar and Microsoft Academic), two aggregate institutional repositories (OAIster and OpenDOAR), and two physics-related open sources (arXiv.org and Astrophysics Data System). The 2001–2013 Nobel Laureates in Physics served as the sample. Bibliographic records of their publications were retrieved and downloaded from each system, and a computer program was developed to perform the analytical tasks of sorting, comparison, elimination, aggregation and statistical calculations. Quantitative analyses and cross-referencing were performed to determine the completeness and overlap of the system coverage of the six open access systems. The results may enable scholars to select an appropriate open access system as an efficient scholarly communication channel, and academic institutions may build institutional repositories or independently create citation index systems in the future. Suggestions on indicators and tools for academic assessment are presented based on the comprehensiveness assessment of each system. PMID:29267327

Independent vs. Integrated Writing Tasks: A Comparison of Task Representation

ERIC Educational Resources Information Center

Plakans, Lia

2010-01-01

As the field of second language writing embraces the authenticity and meaningfulness of connecting writing with other skills, language teachers and testers require greater understanding of how writers respond to as well as compose for integrated tasks. Research on integrated tasks is critical in highlighting how integration impacts students and…

An Attempt to Raise Japanese EFL Learners' Pragmatic Awareness Using Online Discourse Completion Tasks

ERIC Educational Resources Information Center

Tanaka, Hiroya; Oki, Nanaho

2015-01-01

This practical paper discusses the effect of explicit instruction to raise Japanese EFL learners' pragmatic awareness using online discourse completion tasks. The five-part tasks developed by the authors use American TV drama scenes depicting particular speech acts and include explicit instruction in these speech acts. 46 Japanese EFL college…

Effects of White Noise on Off-Task Behavior and Academic Responding for Children with ADHD

ERIC Educational Resources Information Center

Cook, Andrew; Bradley-Johnson, Sharon; Johnson, C. Merle

2014-01-01

We evaluated the effects of white noise played through headphones on off-task behavior, percentage of items completed, and percentage of items completed correctly for 3 students with attention deficit hyperactivity disorder (ADHD). Headphones plus white noise were associated with decreases in off-task behavior relative to baseline and…

Research of cartographer laser SLAM algorithm

NASA Astrophysics Data System (ADS)

Xu, Bo; Liu, Zhengjun; Fu, Yiran; Zhang, Changsai

2017-11-01

As the indoor is a relatively closed and small space, total station, GPS, close-range photogrammetry technology is difficult to achieve fast and accurate indoor three-dimensional space reconstruction task. LIDAR SLAM technology does not rely on the external environment a priori knowledge, only use their own portable lidar, IMU, odometer and other sensors to establish an independent environment map, a good solution to this problem. This paper analyzes the Google Cartographer laser SLAM algorithm from the point cloud matching and closed loop detection. Finally, the algorithm is presented in the 3D visualization tool RViz from the data acquisition and processing to create the environment map, complete the SLAM technology and realize the process of indoor threedimensional space reconstruction

Motion as motivation: using repetitive flexion movements to stimulate the approach system.

PubMed

Haeffel, Gerald J

2011-12-01

Research suggests that having a healthy approach system is critical for adaptive emotional functioning. The goal of the current study (n=186 undergraduates) was to determine the efficacy of an easy-to-disseminate and cost-efficient strategy for stimulating this system. The experiment tested the effects of repeated flexion movements (rFM) on approach system activation as measured by both self-report (BAS scales) and behavior. The results showed that rFM increased approach system motivation in men but not women. Men who completed the rFM task reported significantly greater levels of fun-seeking motivation than men in the control task. Moreover, the rFM task led to changes in actual behavior. Men who completed the rFM task exhibited significantly greater persistence on a difficult laboratory task than men in the control task. In contrast, women who completed the rFM task reported significantly lower levels of fun seeking and tended to exhibit less persistence on a difficult laboratory task than women in the control task. These results provide support for embodied theories of emotion as well as additional evidence for a gender difference in approach-avoidance tendencies. Copyright © 2011. Published by Elsevier Ltd.

Concept mapping: Impact on content and organization of technical writing in science

NASA Astrophysics Data System (ADS)

Conklin, Elaine

The purpose of this quasi-experimental study was to compare the relationship between concept mapping and the content and organization of technical writing of ninth grade biology students. All students in the study completed a prewriting assessment. The experimental group received concept map instruction while the control group performed alternate tasks. After instruction, both groups completed the postwriting assessment and mean differences were compared using the t statistic for independent measures. Additionally, scores on the concept map were correlated to the scores on the postwriting assessment using the Pearson correlation coefficient. Finally, attitudes toward using concept mapping as a prewriting strategy were analyzed using the t statistic for repeated measures. Concept mapping significantly improved the depth of content; however, no statistical significance was detected for organization. Students had a significantly positive change in attitude toward using concept mapping to plan a writing assessment, organize information, and think creatively. The findings indicated concept mapping had a positive effect on the students' abilities to select concepts appropriate to respond to a writing prompt, integrate facts into complete thoughts and ideas, and apply it in novel situations. Concept maps appeared to facilitate learning how to process information and transform it into expository writing. Sustained practice in designing concept maps may influence organization as well as content. Developing a systematic approach to synthesize well-organized and coherent arguments in response to a writing task is an invaluable communication skill that has implications for the learner across disciplines and prepares them for higher education and the workforce.

Perception of Risk and Terrorism-Related Behavior Change: Dual Influences of Probabilistic Reasoning and Reality Testing.

PubMed

Denovan, Andrew; Dagnall, Neil; Drinkwater, Kenneth; Parker, Andrew; Clough, Peter

2017-01-01

The present study assessed the degree to which probabilistic reasoning performance and thinking style influenced perception of risk and self-reported levels of terrorism-related behavior change. A sample of 263 respondents, recruited via convenience sampling, completed a series of measures comprising probabilistic reasoning tasks (perception of randomness, base rate, probability, and conjunction fallacy), the Reality Testing subscale of the Inventory of Personality Organization (IPO-RT), the Domain-Specific Risk-Taking Scale, and a terrorism-related behavior change scale. Structural equation modeling examined three progressive models. Firstly, the Independence Model assumed that probabilistic reasoning, perception of risk and reality testing independently predicted terrorism-related behavior change. Secondly, the Mediation Model supposed that probabilistic reasoning and reality testing correlated, and indirectly predicted terrorism-related behavior change through perception of risk. Lastly, the Dual-Influence Model proposed that probabilistic reasoning indirectly predicted terrorism-related behavior change via perception of risk, independent of reality testing. Results indicated that performance on probabilistic reasoning tasks most strongly predicted perception of risk, and preference for an intuitive thinking style (measured by the IPO-RT) best explained terrorism-related behavior change. The combination of perception of risk with probabilistic reasoning ability in the Dual-Influence Model enhanced the predictive power of the analytical-rational route, with conjunction fallacy having a significant indirect effect on terrorism-related behavior change via perception of risk. The Dual-Influence Model possessed superior fit and reported similar predictive relations between intuitive-experiential and analytical-rational routes and terrorism-related behavior change. The discussion critically examines these findings in relation to dual-processing frameworks. This includes considering the limitations of current operationalisations and recommendations for future research that align outcomes and subsequent work more closely to specific dual-process models.

Perception of Risk and Terrorism-Related Behavior Change: Dual Influences of Probabilistic Reasoning and Reality Testing

PubMed Central

Denovan, Andrew; Dagnall, Neil; Drinkwater, Kenneth; Parker, Andrew; Clough, Peter

2017-01-01

The present study assessed the degree to which probabilistic reasoning performance and thinking style influenced perception of risk and self-reported levels of terrorism-related behavior change. A sample of 263 respondents, recruited via convenience sampling, completed a series of measures comprising probabilistic reasoning tasks (perception of randomness, base rate, probability, and conjunction fallacy), the Reality Testing subscale of the Inventory of Personality Organization (IPO-RT), the Domain-Specific Risk-Taking Scale, and a terrorism-related behavior change scale. Structural equation modeling examined three progressive models. Firstly, the Independence Model assumed that probabilistic reasoning, perception of risk and reality testing independently predicted terrorism-related behavior change. Secondly, the Mediation Model supposed that probabilistic reasoning and reality testing correlated, and indirectly predicted terrorism-related behavior change through perception of risk. Lastly, the Dual-Influence Model proposed that probabilistic reasoning indirectly predicted terrorism-related behavior change via perception of risk, independent of reality testing. Results indicated that performance on probabilistic reasoning tasks most strongly predicted perception of risk, and preference for an intuitive thinking style (measured by the IPO-RT) best explained terrorism-related behavior change. The combination of perception of risk with probabilistic reasoning ability in the Dual-Influence Model enhanced the predictive power of the analytical-rational route, with conjunction fallacy having a significant indirect effect on terrorism-related behavior change via perception of risk. The Dual-Influence Model possessed superior fit and reported similar predictive relations between intuitive-experiential and analytical-rational routes and terrorism-related behavior change. The discussion critically examines these findings in relation to dual-processing frameworks. This includes considering the limitations of current operationalisations and recommendations for future research that align outcomes and subsequent work more closely to specific dual-process models. PMID:29062288

Model construction of “earning money by taking photos”

NASA Astrophysics Data System (ADS)

Yang, Jingmei

2018-03-01

In the era of information, with the increasingly developed network, “to earn money by taking photos” is a self-service model under the mobile Internet. The user downloads the APP, registers as a member of the APP, and then takes a task that needs to take photographs from the APP and earns the reward of the task on the APP. The article uses the task data and membership information data of an already completed project, including the member’s location and reputation value. On the basis of reasonable assumption, the data was processed with the MATLAB, SPSS and Excel software. This article mainly studied problems of the function relationship between the task performance, task position (GPS latitude and GPS longitude) and task price of users, analyzed the project’s task pricing rules and the reasons why the task is not completed, and applied multivariate regression function and GeoQ software to analyze the data, studied the task pricing rules, applied the chart method to solve the complex data, clear and easy to understand, and also reality simulation is applied to analyze why the tasks are not completed. Also, compared with the previous program, a new task pricing program is designed for the project to obtain the confidence level by means of the SPSS software, to estimate the reasonable range of the task pricing, predict and design a new pricing program on the reasonable price range.

Exploring the Relationships between Independent Listening and Listening-Reading-Writing Tasks in Chinese Language Testing: Toward a Better Understanding of the Construct Underlying Integrated Writing Tasks

ERIC Educational Resources Information Center

Zhu, Xinhua; Li, Xueyan; Yu, Guoxing; Cheong, Choo Mui; Liao, Xian

2016-01-01

Integrated assessment tasks have been increasingly used in language tests, but the underlying constructs of integrated tasks remain elusive. This study aimed to improve understanding of the construct of integrated writing tasks in Chinese Language examinations in Hong Kong by looking at the language competences measured in the…

Acute effects of intoxication and arousal on approach / avoidance biases toward sexual risk stimuli in heterosexual men

PubMed Central

Simons, Jeffrey S.; Maisto, Stephen A.; Wray, Tyler B.; Emery, Noah N.

2015-01-01

This study tested the effects of alcohol intoxication and physiological arousal on cognitive biases toward erotic stimuli and condoms. Ninety-seven heterosexual men were randomized to 1 of 6 independent conditions in a 2 (high arousal or control) × 3 (alcohol target BAC = 0.08), placebo, or juice control) design and then completed a variant of the Approach Avoidance Task (AAT). The AAT assessed reaction times toward approaching and avoiding erotic stimuli and condoms with a joystick. Consistent with hypotheses, the alcohol condition exhibited an approach bias toward erotic stimuli, whereas the control and placebo groups exhibited an approach bias toward condom stimuli. Similarly, the participants in the high arousal condition exhibited an approach bias toward erotic stimuli and the low arousal control condition exhibited an approach bias toward condoms. The results suggest that acute changes in intoxication and physiological arousal independently foster biased responding towards sexual stimuli and these biases are associated with sexual risk intentions. PMID:25808719

Domain-independent information extraction in unstructured text

DOE Office of Scientific and Technical Information (OSTI.GOV)

Irwin, N.H.

Extracting information from unstructured text has become an important research area in recent years due to the large amount of text now electronically available. This status report describes the findings and work done during the second year of a two-year Laboratory Directed Research and Development Project. Building on the first-year`s work of identifying important entities, this report details techniques used to group words into semantic categories and to output templates containing selective document content. Using word profiles and category clustering derived during a training run, the time-consuming knowledge-building task can be avoided. Though the output still lacks in completeness whenmore » compared to systems with domain-specific knowledge bases, the results do look promising. The two approaches are compatible and could complement each other within the same system. Domain-independent approaches retain appeal as a system that adapts and learns will soon outpace a system with any amount of a priori knowledge.« less

Orthologs, paralogs and genome comparisons

NASA Technical Reports Server (NTRS)

Gogarten, J. P.; Olendzenski, L.

1999-01-01

During the past decade, ancient gene duplications were recognized as one of the main forces in the generation of diverse gene families and the creation of new functional capabilities. New tools developed to search data banks for homologous sequences, and an increased availability of reliable three-dimensional structural information led to the recognition that proteins with diverse functions can belong to the same superfamily. Analyses of the evolution of these superfamilies promises to provide insights into early evolution but are complicated by several important evolutionary processes. Horizontal transfer of genes can lead to a vertical spread of innovations among organisms, therefore finding a certain property in some descendants of an ancestor does not guarantee that it was present in that ancestor. Complete or partial gene conversion between duplicated genes can yield phylogenetic trees with several, apparently independent gene duplications, suggesting an often surprising parallelism in the evolution of independent lineages. Additionally, the breakup of domains within a protein and the fusion of domains into multifunctional proteins makes the delineation of superfamilies a task that remains difficult to automate.

Logical-rules and the classification of integral dimensions: individual differences in the processing of arbitrary dimensions

PubMed Central

Blunden, Anthea G.; Wang, Tony; Griffiths, David W.; Little, Daniel R.

2015-01-01

A variety of converging operations demonstrate key differences between separable dimensions, which can be analyzed independently, and integral dimensions, which are processed in a non-analytic fashion. A recent investigation of response time distributions, applying a set of logical rule-based models, demonstrated that integral dimensions are pooled into a single coactive processing channel, in contrast to separable dimensions, which are processed in multiple, independent processing channels. This paper examines the claim that arbitrary dimensions created by factorially morphing four faces are processed in an integral manner. In two experiments, 16 participants completed a categorization task in which either upright or inverted morph stimuli were classified in a speeded fashion. Analyses focused on contrasting different assumptions about the psychological representation of the stimuli, perceptual and decisional separability, and the processing architecture. We report consistent individual differences which demonstrate a mixture of some observers who demonstrate coactive processing with other observers who process the dimensions in a parallel self-terminating manner. PMID:25620941

Does order matter? Investigating the effect of sequence on glance duration during on-road driving

PubMed Central

Roberts, Shannon C.; Reimer, Bryan; Mehler, Bruce

2017-01-01

Previous literature has shown that vehicle crash risks increases as drivers’ off-road glance duration increases. Many factors influence drivers’ glance duration such as individual differences, driving environment, or task characteristics. Theories and past studies suggest that glance duration increases as the task progresses, but the exact relationship between glance sequence and glance durations is not fully understood. The purpose of this study was to examine the effect of glance sequence on glance duration among drivers completing a visual-manual radio tuning task and an auditory-vocal based multi-modal navigation entry task. Eighty participants drove a vehicle on urban highways while completing radio tuning and navigation entry tasks. Forty participants drove under an experimental protocol that required three button presses followed by rotation of a tuning knob to complete the radio tuning task while the other forty participants completed the task with one less button press. Multiple statistical analyses were conducted to measure the effect of glance sequence on glance duration. Results showed that across both tasks and a variety of statistical tests, glance sequence had inconsistent effects on glance duration—the effects varied according to the number of glances, task type, and data set that was being evaluated. Results suggest that other aspects of the task as well as interface design effect glance duration and should be considered in the context of examining driver attention or lack thereof. All in all, interface design and task characteristics have a more influential impact on glance duration than glance sequence, suggesting that classical design considerations impacting driver attention, such as the size and location of buttons, remain fundamental in designing in-vehicle interfaces. PMID:28158301

Direct real-time neural evidence for task-set inertia.

PubMed

Evans, Lisa H; Herron, Jane E; Wilding, Edward L

2015-03-01

One influential explanation for the costs incurred when switching between tasks is that they reflect interference arising from completing the previous task-known as task-set inertia. We report a novel approach for assessing task-set inertia in a memory experiment using event-related potentials (ERPs). After a study phase, participants completed a test block in which they switched between a memory task (retrieving information from the study phase) and a perceptual task. These tasks alternated every two trials. An ERP index of the retrieval of study information was evident in the memory task. It was also present on the first trial of the perceptual task but was markedly attenuated on the second. Moreover, this task-irrelevant ERP activity was positively correlated with a behavioral cost associated with switching between tasks. This real-time measure of neural activity thus provides direct evidence of task-set inertia, its duration, and the functional role it plays in switch costs. © The Author(s) 2015.

Mind wandering and the attention network system.

PubMed

Gonçalves, Óscar F; Rêgo, Gabriel; Oliveira-Silva, Patrícia; Leite, Jorge; Carvalho, Sandra; Fregni, Felipe; Amaro, Edson; Boggio, Paulo S

2017-01-01

Attention and mind wandering are often seen as anticorrelated. However, both attention and mind wandering are multi-component processes, and their relationship may be more complex than previously thought. In this study, we tested the interference of different types of thoughts as measured by a Thought Identification Task - TIT (on task thoughts, task related interference thoughts, external distractions, stimulus independent and task unrelated thoughts) on different components of the attention network system - ANT (alerting, orienting, executive). Results show that, during the ANT, individuals were predominantly involved in task related interference thoughts which, along with external distractors, significantly impaired their performance accuracy. However, mind wandering (i.e., stimulus independent and task unrelated thoughts) did not significantly interfere with accuracy in the ANT. No significant relationship was found between type of thoughts and alerting, orienting, or executive effects in the ANT. While task related interference thoughts and external distractions seemed to impair performance on the attention task, mind wandering was still compatible with satisfactory performance in the ANT. The present results confirmed the importance of differentiating type of "out of task" thoughts in studying the relationship between though distractors and attention. Copyright © 2016 Elsevier B.V. All rights reserved.

Assessment of laparoscopic suturing skills of urology residents: a pan-European study.

PubMed

Kroeze, Stephanie G C; Mayer, Erik K; Chopra, Samarth; Aggarwal, Rajesh; Darzi, Ara; Patel, Anup

2009-11-01

It has been acknowledged that standardised training programmes are needed to improve laparoscopic training of urologic trainees. Previous studies have suggested that simulator-based laparoscopic training can improve performance during real laparoscopic procedures. To determine if there are performance differences for the completion of a simulated laparoscopic suturing task among urology residents based on their postgraduate year of training (PGY). Using a validated scoring checklist, two independent observers objectively scored the completion of a standardised laparoscopic suturing task in a bench-top laparoscopic box trainer. PGY and previous exposure to laparoscopic surgery and laparoscopic simulated training was obtained from self-administered questionnaires. Data acquisition was undertaken at the European Urological Residents Education Programme (EUREP) 2007, run by the European School of Urology, and included a pan-European cohort of 201 urology residents. Reliability among those rating the suturing tasks was excellent (Cronbach's α=0.83). Each resident was scored for the suturing task. Residents were categorised into three groups based on their PGY status (junior [n=8]; intermediate [n=37]; senior [n=156]). The Kruskal-Wallis test was used to measure trend across the PGY; the Mann-Whitney U test was used to determine variation among categorised PGY groups. Laparoscopic suturing skill was significantly different across PGY levels (p=0.032), and between junior residents and both intermediate and senior residents (p=0.008 and p=0.012, respectively). There was no significant difference between intermediate and senior residents (p=0.697). Only 12% of participants rated their existing volume of laparoscopic operative cases as sufficient, while 55% of participants had no regular opportunities, and 32% of participants had not performed laparoscopic procedures as primary surgeon. Most residents (96%) reported the use of laparoscopic simulators to be beneficial in training, although current European training programmes appear to provide <50% of residents with the opportunity to train with them. A discernable relationship existed between the score obtained for a laparoscopic suturing task and year of resident training. Modular simulator training as part of a formal training programme may help to overcome some of the shortfall in residents' exposure to laparoscopic procedures as primary surgeon.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Amanda S.; Brosha, Eric

This is a progress report for the demonstration of a prototype hydrogen sensor and electronics package. There are five tasks associated with this, and four have been completed as of August 2016: Station Demonstration and Site Recommendation, Order Sensor Equipment, Build Sensors, and Install Sensors. The final task to be completed is Sensor Demonstration and Data Analysis, and expected completion date is January 26, 2017. This progress report details each of the tasks and goes into detail about what is currently being worked on, along with the budget and planned work for July 27, 2016 to January 26, 2017.

Development of Mouse Models of Ovarian Cancer for Studying Tumor Biology and Testing Novel Molecularly Targeted Therapeutic Strategies

DTIC Science & Technology

2011-09-01

years 2 and 3, Cho laboratory) Task 9: Treatment of tumor-bearing mice with cisplatin accompanied by MRI and BLI (completed years 2 and 3, Rehemtulla...and Cho laboratories) Task 10: Treatment of tumor-bearing mice with perifosine accompanied by MRI and BLI (completed, years 2 and 3, Rehemtulla and...Cho laboratories). Task 11: Treatment of tumor-bearing mice with SC-560 accompanied by MRI and BLI (not performed) Task 12: Histological and

Effects of anxiety on task switching: evidence from the mixed antisaccade task.

PubMed

Ansari, Tahereh L; Derakshan, Nazanin; Richards, Anne

2008-09-01

According to the attentional control theory of anxiety (Eysenck, Derakshan, Santos, & Calvo, 2007), anxiety impairs performance on cognitive tasks that involve the shifting function of working memory. This hypothesis was tested using a mixed antisaccade paradigm, in which participants performed single-task and mixed-task versions of the paradigm. The single task involved the completion of separate blocks of anti- and prosaccade trials, whereas in the mixed task, participants completed anti- and prosaccade trials in a random order within blocks. Analysis of switch costs showed that high-anxious individuals did not exhibit the commonly reported paradoxical improvement in saccade latency, whereas low-anxious individuals did. The findings are discussed within the framework of attentional control theory.

The Effects of a Treatment Package in Establishing Independent Academic Work Skills in Children with Autism.

ERIC Educational Resources Information Center

Pelios, Lillian V.; MacDuff, Gregory S.; Axelrod, Saul

2003-01-01

This study evaluated a treatment package to improve on-task academic skills by three children with autism. Program components included delayed reinforcement for on-task and on-schedule responding, fading of instructional prompts and instructor's presence, unpredictable supervision, and response cost for off-task responding. On-task and on-schedule…

Age and Task-Related Effects on Young Children's Understanding of a Complex Picture Story

ERIC Educational Resources Information Center

Hayward, Denyse; Schneider, Phyllis; Gillam, Ronald B.

2009-01-01

In this study we examined age- and task-related effects in story schema knowledge across an independent narrative task (story formulations) and a supported narrative task (answering questions). We also examined age-related changes to questions about the story as a whole. Participants were typically developing English-speaking children aged 4, 5,…

Impact of Frequent Interruption on Nurses' Patient-Controlled Analgesia Programming Performance.

PubMed

Campoe, Kristi R; Giuliano, Karen K

2017-12-01

The purpose was to add to the body of knowledge regarding the impact of interruption on acute care nurses' cognitive workload, total task completion times, nurse frustration, and medication administration error while programming a patient-controlled analgesia (PCA) pump. Data support that the severity of medication administration error increases with the number of interruptions, which is especially critical during the administration of high-risk medications. Bar code technology, interruption-free zones, and medication safety vests have been shown to decrease administration-related errors. However, there are few published data regarding the impact of number of interruptions on nurses' clinical performance during PCA programming. Nine acute care nurses completed three PCA pump programming tasks in a simulation laboratory. Programming tasks were completed under three conditions where the number of interruptions varied between two, four, and six. Outcome measures included cognitive workload (six NASA Task Load Index [NASA-TLX] subscales), total task completion time (seconds), nurse frustration (NASA-TLX Subscale 6), and PCA medication administration error (incorrect final programming). Increases in the number of interruptions were associated with significant increases in total task completion time ( p = .003). We also found increases in nurses' cognitive workload, nurse frustration, and PCA pump programming errors, but these increases were not statistically significant. Complex technology use permeates the acute care nursing practice environment. These results add new knowledge on nurses' clinical performance during PCA pump programming and high-risk medication administration.

The effect of errorless learning on quality of life in patients with Korsakoff's syndrome.

PubMed

Rensen, Yvonne Cm; Egger, Jos Im; Westhoff, Josette; Walvoort, Serge Jw; Kessels, Roy Pc

2017-01-01

Errorless learning (EL) is a promising rehabilitation principle for (re)learning instrumental activities in patients with amnesia, including patients with Korsakoff's syndrome (KS). Successfully (re)learning tasks might improve the sense of competence and independence, and subsequently the quality of life. Quality of life in patients with KS has received limited attention, and no studies have been conducted to experimentally examine the effect of EL on quality of life in patients in this patient group. The QUALIDEM, an observation scale for quality of life, was completed by professional nurses before and after EL training in a group of fifty-one patients with KS. This scale was also completed for a group of thirty-one control patients receiving care as usual but no EL training. Quality of life was significantly increased on eight of the nine subscales in the Korsakoff group who participated in an EL training. There was a trend toward a significant increase in "positive affect" (ie, the ninth subscale). In contrast, no changes over time were found on any of the subscales in the control group that did not participate in any EL training. Despite severe memory impairments, patients with KS still have the potential to (partially) (re)learn tasks using EL. This potential should be exploited, as the successes of (re)-learning might improve the quality of life of Korsakoff patients in nursing homes.

Differential roles of resistance to proactive interference and suppression of prepotent responses in overgeneral memory.

PubMed

Comas, Michelle; Valentino, Kristin; Johnson, Anne F; Gibson, Bradley S; Taylor, Courtney

2018-06-12

Overgeneral memory (OGM), difficulty in retrieving specific autobiographical memories, is a robust phenomenon related to the onset and course of depressive and posttraumatic stress disorders. Inhibitory mechanisms are theorized to underlie OGM; however, empirical support for this link is equivocal. The current study examines the differential roles of two aspects of inhibitory control in association with OGM: suppression of prepotent responses and resistance to proactive interference (PI). Only resistance to PI was expected to be negatively related to OGM, whereby individuals with greater ability to resist PI would have reduced OGM. Participants (n = 49) completed a self-report measure of depressive symptoms and engaged in two tasks aimed at assessing resistance to PI and suppression of prepotent responses. Participants also completed a task assessing overgeneral autobiographical memory. As hypothesized, resistance to PI, but not suppression of prepotent responses negatively predicted OGM above and beyond the influence of depressive symptoms. Because a double dissociation was not examined, we cannot address the potential independence of the submechanisms of inhibitory control that we assessed. Results exemplify the differential associations of two components of inhibition and OGM, suggesting that resistance to PI, in particular, may contribute to the development and/or maintenance of OGM and associated depressive disorders. Directions for future research are discussed. Copyright © 2018. Published by Elsevier Ltd.

Interrelationships between Marijuana Demand and Discounting of Delayed Rewards: Convergence in Behavioral Economic Methods

PubMed Central

Aston, Elizabeth R.; Metrik, Jane; Amlung, Michael; Kahler, Christopher W.; MacKillop, James

2016-01-01

Background Distinct behavioral economic domains, including high perceived drug value (demand) and delay discounting (DD), have been implicated in the initiation of drug use and the progression to dependence. However, it is unclear whether frequent marijuana users conform to a “reinforcer pathology” addiction model wherein marijuana demand and DD jointly increase risk for problematic marijuana use and cannabis dependence (CD). Methods Participants (n=88, 34% female, 14% cannabis dependent) completed a marijuana purchase task at baseline. A delay discounting task was completed following placebo marijuana cigarette (0% THC) administration during a separate experimental session. Results Marijuana demand and DD were quantified using area under the curve (AUC). In multiple regression models, demand uniquely predicted frequency of marijuana use while DD did not. In contrast, DD uniquely predicted CD symptom count while demand did not. There were no significant interactions between demand and DD in either model. Conclusions These findings suggest that frequent marijuana users exhibit key constituents of the reinforcer pathology model: high marijuana demand and steep discounting of delayed rewards. However, demand and DD appear to be independent rather than synergistic risk factors for elevated marijuana use and risk for progression to CD. Findings also provide support for using AUC as a singular marijuana demand metric, particularly when also examining other behavioral economic constructs that apply similar statistical approaches, such as DD, to support analytic methodological convergence. PMID:27810657

Impact of episodic thinking on altruism

PubMed Central

Yi, Richard; Pickover, Alison; Stuppy-Sullivan, Allison M.; Baker, Sydney; Landes, Reid D.

2016-01-01

Episodic future thinking, which refers to the use of prospective imagery to concretely imagine oneself in future scenarios, has been shown to reduce delay discounting (enhance self-control). A parallel approach, in which prospective imagery is used to concretely imagine other’s scenarios, may similarly reduce social discounting (i.e., enhance altruism). In study 1, participants engaged in episodic thinking about the self or others, in a repeated-measures design, while completing a social discounting task. Reductions in social discounting were observed as a function of episodic thinking about others, though an interaction with order was also observed. Using an independent-measures design in study 2, the effect of episodic thinking about others was replicated. Study 3 addressed a limitation of studies 1 and 2, the possibility that simply thinking about others decreased social discounting. Capitalizing on Construal Level Theory, which specifies that social distance and time in the future are both dimensions of a common psychological distance, we hypothesized that episodic future thinking should also decrease social discounting. Participants engaged in episodic future thinking or episodic present thinking, in a repeated-measures design, while completing a social discounting task. The pattern of results was similar to study 1, providing support for the notion that episodic thinking about psychologically distant outcomes (for others or in the future) reduces social discounting. Application of similar episodic thinking approaches may enhance altruism. PMID:27821875

Task-Dependent Intermuscular Motor Unit Synchronization between Medial and Lateral Vastii Muscles during Dynamic and Isometric Squats.

PubMed

Mohr, Maurice; Nann, Marius; von Tscharner, Vinzenz; Eskofier, Bjoern; Nigg, Benno Maurus

2015-01-01

Motor unit activity is coordinated between many synergistic muscle pairs but the functional role of this coordination for the motor output is unclear. The purpose of this study was to investigate the short-term modality of coordinated motor unit activity-the synchronized discharge of individual motor units across muscles within time intervals of 5ms-for the Vastus Medialis (VM) and Lateralis (VL). Furthermore, we studied the task-dependency of intermuscular motor unit synchronization between VM and VL during static and dynamic squatting tasks to provide insight into its functional role. Sixteen healthy male and female participants completed four tasks: Bipedal squats, single-leg squats, an isometric squat, and single-leg balance. Monopolar surface electromyography (EMG) was used to record motor unit activity of VM and VL. For each task, intermuscular motor unit synchronization was determined using a coherence analysis between the raw EMG signals of VM and VL and compared to a reference coherence calculated from two desynchronized EMG signals. The time shift between VM and VL EMG signals was estimated according to the slope of the coherence phase angle spectrum. For all tasks, except for singe-leg balance, coherence between 15-80Hz significantly exceeded the reference. The corresponding time shift between VM and VL was estimated as 4ms. Coherence between 30-60Hz was highest for the bipedal squat, followed by the single-leg squat and the isometric squat. There is substantial short-term motor unit synchronization between VM and VL. Intermuscular motor unit synchronization is enhanced for contractions during dynamic activities, possibly to facilitate a more accurate control of the joint torque, and reduced during single-leg tasks that require balance control and thus, a more independent muscle function. It is proposed that the central nervous system scales the degree of intermuscular motor unit synchronization according to the requirements of the movement task at hand.

Task-Dependent Intermuscular Motor Unit Synchronization between Medial and Lateral Vastii Muscles during Dynamic and Isometric Squats

PubMed Central

Mohr, Maurice; Nann, Marius; von Tscharner, Vinzenz; Eskofier, Bjoern; Nigg, Benno Maurus

2015-01-01

Purpose Motor unit activity is coordinated between many synergistic muscle pairs but the functional role of this coordination for the motor output is unclear. The purpose of this study was to investigate the short-term modality of coordinated motor unit activity–the synchronized discharge of individual motor units across muscles within time intervals of 5ms–for the Vastus Medialis (VM) and Lateralis (VL). Furthermore, we studied the task-dependency of intermuscular motor unit synchronization between VM and VL during static and dynamic squatting tasks to provide insight into its functional role. Methods Sixteen healthy male and female participants completed four tasks: Bipedal squats, single-leg squats, an isometric squat, and single-leg balance. Monopolar surface electromyography (EMG) was used to record motor unit activity of VM and VL. For each task, intermuscular motor unit synchronization was determined using a coherence analysis between the raw EMG signals of VM and VL and compared to a reference coherence calculated from two desynchronized EMG signals. The time shift between VM and VL EMG signals was estimated according to the slope of the coherence phase angle spectrum. Results For all tasks, except for singe-leg balance, coherence between 15–80Hz significantly exceeded the reference. The corresponding time shift between VM and VL was estimated as 4ms. Coherence between 30–60Hz was highest for the bipedal squat, followed by the single-leg squat and the isometric squat. Conclusion There is substantial short-term motor unit synchronization between VM and VL. Intermuscular motor unit synchronization is enhanced for contractions during dynamic activities, possibly to facilitate a more accurate control of the joint torque, and reduced during single-leg tasks that require balance control and thus, a more independent muscle function. It is proposed that the central nervous system scales the degree of intermuscular motor unit synchronization according to the requirements of the movement task at hand. PMID:26529604

Advanced, Low/Zero Emission Boiler Design and Operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Babcock /Wilcox; Illinois State Geological; Worley Parsons

2007-06-30

In partnership with the U.S. Department of Energy's National Energy Technology Laboratory, B&W and Air Liquide are developing and optimizing the oxy-combustion process for retrofitting existing boilers as well as new plants. The main objectives of the project is to: (1) demonstrate the feasibility of the oxy-combustion technology with flue gas recycle in a 5-million Btu/hr coal-fired pilot boiler, (2) measure its performances in terms of emissions and boiler efficiency while selecting the right oxygen injection and flue gas recycle strategies, and (3) perform technical and economic feasibility studies for application of the technology in demonstration and commercial scale boilers.more » This document summarizes the work performed during the period of performance of the project (Oct 2002 to June 2007). Detailed technical results are reported in corresponding topical reports that are attached as an appendix to this report. Task 1 (Site Preparation) has been completed in 2003. The experimental pilot-scale O{sub 2}/CO{sub 2} combustion tests of Task 2 (experimental test performance) has been completed in Q2 2004. Process simulation and cost assessment of Task 3 (Techno-Economic Study) has been completed in Q1 2005. The topical report on Task 3 has been finalized and submitted to DOE in Q3 2005. The calculations of Task 4 (Retrofit Recommendation and Preliminary Design of a New Generation Boiler) has been completed in 2004. In Task 6 (engineering study on retrofit applications), the engineering study on 25MW{sub e} unit has been completed in Q2, 2008 along with the corresponding cost assessment. In Task 7 (evaluation of new oxy-fuel power plants concepts), based on the design basis document prepared in 2005, the design and cost estimate of the Air Separation Units, the boiler islands and the CO{sub 2} compression and trains have been completed, for both super and ultra-supercritical case study. Final report of Task-7 is published by DOE in Oct 2007.« less

Role of self-efficacy and anxiety among pre-clinically disabled older adults when using compensatory strategies to complete daily tasks

PubMed Central

Higgins, Torrance J.; Janelle, Christopher M.; Naugle, Kelly M.; Knaggs, Jeffrey; Hoover, Brian M.; Marsiske, Michael; Manini, Todd M.

2012-01-01

Classic developmental theory suggests that aging is associated with using compensatory strategies to prolong independence. While compensatory strategies are typically considered positive adaptations, they also signify an early phase in the disablement process — commonly known as pre-clinical disability. To build a better understanding of psychological constructs related to these early signs of disability, we examined the contribution of self-efficacy and state anxiety on using compensatory strategies among pre-clinically disabled older adults. Compensatory strategies were observed during performance of daily activities in 257 pre-clinically disabled older adults (67.6 ± 7.04), and self-efficacy and state anxiety were evaluated prior to performing each task. In univariate models, lower self-efficacy and higher anxiety were associated with more compensation (Spearman correlations: 0.15-0.48, p < 0.05). Multivariate logistic regression indicated that low self-efficacy [Odds Ratio (OR): 1.70; 95% Confidence Interval (CI): 1.40-2.08) and high anxiety (OR: 1.34; 95% CI: 1.10-1.63) were positively associated with using ≥ 6 compensatory strategies – a level signifying substantial compensation. When considered jointly with self-efficacy, the association with anxiety was reversed— higher anxiety demonstrated a lower likelihood of using compensation (OR: 0.70-0.73; 95% CI: 0.50-0.99). The addition of self-efficacy might remove the self-defeating cognitions characterizing anxiety allowing the remaining arousal component to appear beneficial. In conclusion, lower self-efficacy and higher anxiety are associated with using compensation to complete daily tasks among pre-clinically disabled older adults. Such psychological constructs may contribute to the use of compensatory strategies and represent future intervention targets to help reduce early signs of disability. PMID:22770713

Differential influence of asynchrony in early and late chronotypes on convergent thinking.

PubMed

Simor, Péter; Polner, Bertalan

2017-01-01

Eveningness preference (late chronotype) was previously associated with different personality dimensions and thinking styles that were linked to creativity, suggesting that evening-type individuals tend to be more creative than the morning-types. Nevertheless, empirical data on the association between chronotype and creative performance is scarce and inconclusive. Moreover, cognitive processes related to creative thinking are influenced by other factors such as sleep and the time of testing. Therefore, our aim was to examine convergent and divergent thinking abilities in late and early chronotypes, taking into consideration the influence of asynchrony (optimal versus nonoptimal testing times) and sleep quality. We analyzed the data of 36 evening-type and 36 morning-type young, healthy adults who completed the Compound Remote Associates (CRAs) as a convergent and the Just suppose subtest of the Torrance Tests of Creative Thinking as a divergent thinking task within a time interval that did (n = 32) or did not (n = 40) overlap with their individually defined peak times. Chronotype was not directly associated with creative performance, but in case of the convergent thinking task an interaction between chronotype and asynchrony emerged. Late chronotypes who completed the test at subjectively nonoptimal times showed better performance than late chronotypes tested during their "peak" and early chronotypes tested at their peak or off-peak times. Although insomniac symptoms predicted lower scores in the convergent thinking task, the interaction between chronotype and asynchrony was independent of the effects of sleep quality or the general testing time. Divergent thinking was not predicted by chronotype, asynchrony or their interaction. Our findings indicate that asynchrony might have a beneficial influence on convergent thinking, especially in late chronotypes.

Non-image forming effects of illuminance level: Exploring parallel effects on physiological arousal and task performance.

PubMed

Huiberts, Laura M; Smolders, Karin C H J; de Kort, Yvonne A W

2016-10-01

This study investigated diurnal non-image forming (NIF) effects of illuminance level on physiological arousal in parallel to NIF effects on vigilance and working memory performance. We employed a counterbalanced within-subjects design in which thirty-nine participants (mean age=21.2; SD=2.1; 11 male) completed three 90-min sessions (165 vs. 600lx vs. 1700lx at eye level) either in the morning (N=18) or afternoon (N=21). During each session, participants completed four measurement blocks (incl. one baseline block) each consisting of a 10-min Psychomotor Vigilance Task (PVT) and a Backwards Digit-Span Task (BDST) including easy trials (4-6 digits) and difficult trials (7-8 digits). Heart rate (HR), skin conductance level (SCL) and systolic blood pressure (SBP) were measured continuously. The results revealed significant improvements in performance on the BDST difficult trials under 1700lx vs. 165lx (p=0.01), while illuminance level did not affect performance on the PVT and BDST easy trials. Illuminance level impacted HR and SCL, but not SBP. In the afternoon sessions, HR was significantly higher under 1700lx vs. 165lx during PVT performance (p=0.05), while during BDST performance, HR was only slightly higher under 600 vs. 165lx (p=0.06). SCL was significantly higher under 1700lx vs. 165lx during performance on BDST easy trials (p=0.02) and showed similar, but nonsignificant trends during the PVT and BDST difficult trials. Although both physiology and performance were affected by illuminance level, no consistent pattern emerged with respect to parallel changes in physiology and performance. Rather, physiology and performance seemed to be affected independently, via unique pathways. Copyright © 2016. Published by Elsevier Inc.

Health Literacy and Task Environment Influence Parents' Burden for Data Entry on Child-Specific Health Information: Randomized Controlled Trial

PubMed Central

Guo, Chao-Yu; Bacic, Janine; Chan, Eugenia

2011-01-01

Background Health care systems increasingly rely on patients’ data entry efforts to organize and assist in care delivery through health information exchange. Objectives We sought to determine (1) the variation in burden imposed on parents by data entry efforts across paper-based and computer-based environments, and (2) the impact, if any, of parents’ health literacy on the task burden. Methods We completed a randomized controlled trial of parent-completed data entry tasks. Parents of children with attention deficit hyperactivity disorder (ADHD) were randomized based on the Test of Functional Health Literacy in Adults (TOFHLA) to either a paper-based or computer-based environment for entry of health information on their children. The primary outcome was the National Aeronautics and Space Administration Task Load Index (TLX) total weighted score. Results We screened 271 parents: 194 (71.6%) were eligible, and 180 of these (92.8%) constituted the study cohort. We analyzed 90 participants from each arm. Parents who completed information tasks on paper reported a higher task burden than those who worked in the computer environment: mean (SD) TLX scores were 22.8 (20.6) for paper and 16.3 (16.1) for computer. Assignment to the paper environment conferred a significant risk of higher task burden (F1,178 = 4.05, P = .046). Adequate literacy was associated with lower task burden (decrease in burden score of 1.15 SD, P = .003). After adjusting for relevant child and parent factors, parents’ TOFHLA score (beta = -.02, P = .02) and task environment (beta = .31, P = .03) remained significantly associated with task burden. Conclusions A tailored computer-based environment provided an improved task experience for data entry compared to the same tasks completed on paper. Health literacy was inversely related to task burden. Trial registration Clinicaltrials.gov NCT00543257; http://www.clinicaltrials.gov/ct2/show/NCT00543257 (Archived by WebCite at http://www.webcitation.org/5vUVH2DYR) PMID:21269990

Flipping Radiology Education Right Side Up.

PubMed

O'Connor, Erin E; Fried, Jessica; McNulty, Nancy; Shah, Pallav; Hogg, Jeffery P; Lewis, Petra; Zeffiro, Thomas; Agarwal, Vikas; Reddy, Sravanthi

2016-07-01

In flipped learning, medical students independently learn facts and concepts outside the classroom, and then participate in interactive classes to learn to apply these facts. Although there are recent calls for medical education reform using flipped learning, little has been published on its effectiveness. Our study compares the effects of flipped learning to traditional didactic instruction on students' academic achievement, task value, and achievement emotions. At three institutions, we alternated flipped learning with traditional didactic lectures during radiology clerkships, with 175 medical students completing a pretest on general diagnostic imaging knowledge to assess baseline cohort comparability. Following instruction, posttests and survey examinations of task value and achievement emotions were administered. Linear mixed effects analysis was used to examine the relationship between test scores and instruction type. Survey responses were modeled using ordinal category logistic regression. Instructor surveys were also collected. There were no baseline differences in test scores. Mean posttest minus pretest scores were 10.5% higher in the flipped learning group than in the didactic instruction group (P = 0.013). Assessment of task value and achievement emotions showed greater task value, increased enjoyment, and decreased boredom with flipped learning (all P < 0.01). All instructors preferred the flipped learning condition. Flipped learning was associated with increased academic achievement, greater task value, and more positive achievement emotions when compared to traditional didactic instruction. Further investigation of flipped learning methods in radiology education is needed to determine whether flipped learning improves long-term retention of knowledge, academic success, and patient care. Copyright © 2016 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

"Looking-at-nothing" during sequential sensorimotor actions: Long-term memory-based eye scanning of remembered target locations.

PubMed

Foerster, Rebecca M

2018-03-01

Before acting humans saccade to a target object to extract relevant visual information. Even when acting on remembered objects, locations previously occupied by relevant objects are fixated during imagery and memory tasks - a phenomenon called "looking-at-nothing". While looking-at-nothing was robustly found in tasks encouraging declarative memory built-up, results are mixed in the case of procedural sensorimotor tasks. Eye-guidance to manual targets in complete darkness was observed in a task practiced for days beforehand, while investigations using only a single session did not find fixations to remembered action targets. Here, it is asked whether looking-at-nothing can be found in a single sensorimotor session and thus independent from sleep consolidation, and how it progresses when visual information is repeatedly unavailable. Eye movements were investigated in a computerized version of the trail making test. Participants clicked on numbered circles in ascending sequence. Fifty trials were performed with the same spatial arrangement of 9 visual targets to enable long-term memory consolidation. During 50 consecutive trials, participants had to click the remembered target sequence on an empty screen. Participants scanned the visual targets and also the empty target locations sequentially with their eyes, however, the latter less precise than the former. Over the course of the memory trials, manual and oculomotor sequential target scanning became more similar to the visual trials. Results argue for robust looking-at-nothing during procedural sensorimotor tasks provided that long-term memory information is sufficient. Copyright © 2018 Elsevier Ltd. All rights reserved.

Music-induced changes in functional cerebral asymmetries.

PubMed

Hausmann, Markus; Hodgetts, Sophie; Eerola, Tuomas

2016-04-01

After decades of research, it remains unclear whether emotion lateralization occurs because one hemisphere is dominant for processing the emotional content of the stimuli, or whether emotional stimuli activate lateralised networks associated with the subjective emotional experience. By using emotion-induction procedures, we investigated the effect of listening to happy and sad music on three well-established lateralization tasks. In a prestudy, Mozart's piano sonata (K. 448) and Beethoven's Moonlight Sonata were rated as the most happy and sad excerpts, respectively. Participants listened to either one emotional excerpt, or sat in silence before completing an emotional chimeric faces task (Experiment 1), visual line bisection task (Experiment 2) and a dichotic listening task (Experiment 3 and 4). Listening to happy music resulted in a reduced right hemispheric bias in facial emotion recognition (Experiment 1) and visuospatial attention (Experiment 2) and increased left hemispheric bias in language lateralization (Experiments 3 and 4). Although Experiments 1-3 revealed an increased positive emotional state after listening to happy music, mediation analyses revealed that the effect on hemispheric asymmetries was not mediated by music-induced emotional changes. The direct effect of music listening on lateralization was investigated in Experiment 4 in which tempo of the happy excerpt was manipulated by controlling for other acoustic features. However, the results of Experiment 4 made it rather unlikely that tempo is the critical cue accounting for the effects. We conclude that listening to music can affect functional cerebral asymmetries in well-established emotional and cognitive laterality tasks, independent of music-induced changes in the emotion state. Copyright © 2016 Elsevier Inc. All rights reserved.

Rhesus monkeys employ a procedural strategy to reduce working memory load in a self-ordered spatial search task

PubMed Central

Taffe, Michael A.; Taffe, William J.

2011-01-01

Several nonhuman primate species have been reported to employ a distance-minimizing, traveling salesman-like, strategy during foraging as well as in experimental spatial search tasks involving lesser amounts of locomotion. Spatial sequencing may optimize performance by reducing reference or episodic memory loads, locomotor costs, competition or other demands. A computerized self-ordered spatial search (SOSS) memory task has been adapted from a human neuropsychological testing battery (CANTAB, Cambridge Cognition, Ltd) for use in monkeys. Accurate completion of a trial requires sequential responses to colored boxes in two or more spatial locations without repetition of a previous location. Marmosets have been reported to employ a circling pattern of search, suggesting spontaneous adoption of a strategy to reduce working memory load. In this study the SOSS performance of rhesus monkeys was assessed to determine if the use of a distance-minimizing search path enhances accuracy. A novel strategy score, independent of the trial difficulty and arrangement of boxes, has been devised. Analysis of the performance of 21 monkeys trained on SOSS over two years shows that a distance-minimizing search strategy is associated with improved accuracy. This effect is observed within individuals as they improve over many cumulative sessions of training on the task and across individuals at any given level of training. Erroneous trials were associated with a failure to deploy the strategy. It is concluded that the effect of utilizing the strategy on this locomotion-free, laboratory task is to enhance accuracy by reducing demands on spatial working memory resources. PMID:21840507

Cognitive Fatigue Influences Time-On-Task during Bodyweight Resistance Training Exercise

PubMed Central

Head, James R.; Tenan, Matthew S.; Tweedell, Andrew J.; Price, Thomas F.; LaFiandra, Michael E.; Helton, William S.

2016-01-01

Prior investigations have shown measurable performance impairments on continuous physical performance tasks when preceded by a cognitively fatiguing task. However, the effect of cognitive fatigue on bodyweight resistance training exercise task performance is unknown. In the current investigation 18 amateur athletes completed a full body exercise task preceded by either a cognitive fatiguing or control intervention. In a randomized repeated measure design, each participant completed the same exercise task preceded by a 52 min cognitively fatiguing intervention (vigilance) or control intervention (video). Data collection sessions were separated by 1 week. Participants rated the fatigue intervention with a significantly higher workload compared to the control intervention (p < 0.001). Additionally, participants self-reported significantly greater energetic arousal for cognitively fatiguing task (p = 0.02). Cognitive fatigue did not significantly impact number of repetitions completed during the exercise task (p = 0.77); however, when cognitively fatigued, participants had decreased percent time-on-task (57%) relative to the no fatigue condition (60%; p = 0.04). RPE significantly changed over time (p < 0.001), but failed to show significant differences between the cognitive fatigue intervention and control intervention (p > 0.05). There was no statistical difference for heart rate or metabolic expenditure as a function of fatigue intervention during exercise. Cognitively fatigued athletes have decreased time-on-task in bodyweight resistance training exercise tasks. PMID:27635122

Effects of a Photo Activity Schedule Book on Independent Task Changes by Students with Intellectual Disabilities in Community and School Job Sites

ERIC Educational Resources Information Center

Carson, Keyla D; Gast, David L.; Ayres, Kevin M.

2008-01-01

The purpose of this study was to evaluate the effectiveness of using a photo activity schedule book to increase independent transitioning between vocational tasks inside a school cafeteria and at a community job site. Three students with mild to moderate intellectual disabilities, enrolled in a self-contained classroom in a public high school,…

KENNEDY SPACE CENTER, FLA. - The Stafford-Covey Return to Flight Task Group (SCTG) inspects debris in the Columbia Debris Hangar. At right is the model of the left wing that has been used during recovery operations. Chairing the task group are Richard O. Covey, former Space Shuttle commander, and Thomas P. Stafford (third from right, foreground), Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

NASA Image and Video Library

2003-08-05

KENNEDY SPACE CENTER, FLA. - The Stafford-Covey Return to Flight Task Group (SCTG) inspects debris in the Columbia Debris Hangar. At right is the model of the left wing that has been used during recovery operations. Chairing the task group are Richard O. Covey, former Space Shuttle commander, and Thomas P. Stafford (third from right, foreground), Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

Changes in dynamic resting state network connectivity following aphasia therapy.

PubMed

Duncan, E Susan; Small, Steven L

2017-10-24

Resting state magnetic resonance imaging (rsfMRI) permits observation of intrinsic neural networks produced by task-independent correlations in low frequency brain activity. Various resting state networks have been described, with each thought to reflect common engagement in some shared function. There has been limited investigation of the plasticity in these network relationships after stroke or induced by therapy. Twelve individuals with language disorders after stroke (aphasia) were imaged at multiple time points before (baseline) and after an imitation-based aphasia therapy. Language assessment using a narrative production task was performed at the same time points. Group independent component analysis (ICA) was performed on the rsfMRI data to identify resting state networks. A sliding window approach was then applied to assess the dynamic nature of the correlations among these networks. Network correlations during each 30-second window were used to cluster the data into ten states for each window at each time point for each subject. Correlation was performed between changes in time spent in each state and therapeutic gains on the narrative task. The amount of time spent in a single one of the (ten overall) dynamic states was positively associated with behavioral improvement on the narrative task at the 6-week post-therapy maintenance interval, when compared with either baseline or assessment immediately following therapy. This particular state was characterized by minimal correlation among the task-independent resting state networks. Increased functional independence and segregation of resting state networks underlies improvement on a narrative production task following imitation-based aphasia treatment. This has important clinical implications for the targeting of noninvasive brain stimulation in post-stroke remediation.

Sleep-Effects on Implicit and Explicit Memory in Repeated Visual Search

PubMed Central

Assumpcao, Leonardo; Gais, Steffen

2013-01-01

In repeated visual search tasks, facilitation of reaction times (RTs) due to repetition of the spatial arrangement of items occurs independently of RT facilitation due to improvements in general task performance. Whereas the latter represents typical procedural learning, the former is a kind of implicit memory that depends on the medial temporal lobe (MTL) memory system and is impaired in patients with amnesia. A third type of memory that develops during visual search is the observers’ explicit knowledge of repeated displays. Here, we used a visual search task to investigate whether procedural memory, implicit contextual cueing, and explicit knowledge of repeated configurations, which all arise independently from the same set of stimuli, are influenced by sleep. Observers participated in two experimental sessions, separated by either a nap or a controlled rest period. In each of the two sessions, they performed a visual search task in combination with an explicit recognition task. We found that (1) across sessions, MTL-independent procedural learning was more pronounced for the nap than rest group. This confirms earlier findings, albeit from different motor and perceptual tasks, showing that procedural memory can benefit from sleep. (2) Likewise, the sleep group compared with the rest group showed enhanced context-dependent configural learning in the second session. This is a novel finding, indicating that the MTL-dependent, implicit memory underlying contextual cueing is also sleep-dependent. (3) By contrast, sleep and wake groups displayed equivalent improvements in explicit recognition memory in the second session. Overall, the current study shows that sleep affects MTL-dependent as well as MTL-independent memory, but it affects different, albeit simultaneously acquired, forms of MTL-dependent memory differentially. PMID:23936363

Anatomical constraints on attention: Hemifield independence is a signature of multifocal spatial selection

PubMed Central

Alvarez, George A; Gill, Jonathan; Cavanagh, Patrick

2012-01-01

Previous studies have shown independent attentional selection of targets in the left and right visual hemifields during attentional tracking (Alvarez & Cavanagh, 2005) but not during a visual search (Luck, Hillyard, Mangun, & Gazzaniga, 1989). Here we tested whether multifocal spatial attention is the critical process that operates independently in the two hemifields. It is explicitly required in tracking (attend to a subset of object locations, suppress the others) but not in the standard visual search task (where all items are potential targets). We used a modified visual search task in which observers searched for a target within a subset of display items, where the subset was selected based on location (Experiments 1 and 3A) or based on a salient feature difference (Experiments 2 and 3B). The results show hemifield independence in this subset visual search task with location-based selection but not with feature-based selection; this effect cannot be explained by general difficulty (Experiment 4). Combined, these findings suggest that hemifield independence is a signature of multifocal spatial attention and highlight the need for cognitive and neural theories of attention to account for anatomical constraints on selection mechanisms. PMID:22637710

The Effect of Two-dimensional and Stereoscopic Presentation on Middle School Students' Performance of Spatial Cognition Tasks

NASA Astrophysics Data System (ADS)

Price, Aaron; Lee, Hee-Sun

2010-02-01

We investigated whether and how student performance on three types of spatial cognition tasks differs when worked with two-dimensional or stereoscopic representations. We recruited nineteen middle school students visiting a planetarium in a large Midwestern American city and analyzed their performance on a series of spatial cognition tasks in terms of response accuracy and task completion time. Results show that response accuracy did not differ between the two types of representations while task completion time was significantly greater with the stereoscopic representations. The completion time increased as the number of mental manipulations of 3D objects increased in the tasks. Post-interviews provide evidence that some students continued to think of stereoscopic representations as two-dimensional. Based on cognitive load and cue theories, we interpret that, in the absence of pictorial depth cues, students may need more time to be familiar with stereoscopic representations for optimal performance. In light of these results, we discuss potential uses of stereoscopic representations for science learning.

Forced Aerobic Exercise Preceding Task Practice Improves Motor Recovery Poststroke.

PubMed

Linder, Susan M; Rosenfeldt, Anson B; Dey, Tanujit; Alberts, Jay L

To understand how two types of aerobic exercise affect upper-extremity motor recovery post-stroke. Our aims were to (1) evaluate the feasibility of having people who had a stroke complete an aerobic exercise intervention and (2) determine whether forced or voluntary exercise differentially facilitates upper-extremity recovery when paired with task practice. Seventeen participants with chronic stroke completed twenty-four 90-min sessions over 8 wk. Aerobic exercise was immediately followed by task practice. Participants were randomized to forced or voluntary aerobic exercise groups or to task practice only. Improvement on the Fugl-Meyer Assessment exceeded the minimal clinically important difference: 12.3, 4.8, and 4.4 for the forced exercise, voluntary exercise, and repetitive task practice-only groups, respectively. Only the forced exercise group exhibited a statistically significant improvement. People with chronic stroke can safely complete intensive aerobic exercise. Forced aerobic exercise may be optimal in facilitating motor recovery associated with task practice. Copyright © 2017 by the American Occupational Therapy Association, Inc.

Differences in problem-solving between canid populations: Do domestication and lifetime experience affect persistence?

PubMed

Brubaker, Lauren; Dasgupta, Sandipan; Bhattacharjee, Debottam; Bhadra, Anindita; Udell, Monique A R

2017-07-01

Past research has suggested that a variety of factors, phylogenetic and ontogenetic, play a role in how canines behave during problem-solving tasks and the degree to which the presence of a human influences their problem-solving behaviour. While comparisons between socialized wolves and domestic dogs have commonly been used to tease apart these predictive factors, in many cases a single dog population, often pets, have been used for these comparisons. Less is understood about how different populations of dogs may behave when compared with wolves, or with each other, during an independent problem-solving task. This experiment compared the independent persistence of four populations of canines (two groups of pet domestic dogs, a group of free-ranging domestic dogs, and human-socialized wolves) on an independent problem-solving task in the presence of an on looking human. Results showed that wolves persisted the most at the task while free-ranging dogs persisted the least. Free-ranging dogs gazed at the human experimenter for the longest durations during the task. While further research is needed to understand why these differences exist, this study demonstrates that dogs, even those living outside human homes as scavengers, show comparatively low levels of persistence when confronted with a solvable task in the presence of a human as well as significantly greater duration of human-directed gaze when compared with wolves.

Functional split brain in a driving/listening paradigm

PubMed Central

Boly, Melanie; Mensen, Armand; Tononi, Giulio

2016-01-01

We often engage in two concurrent but unrelated activities, such as driving on a quiet road while listening to the radio. When we do so, does our brain split into functionally distinct entities? To address this question, we imaged brain activity with fMRI in experienced drivers engaged in a driving simulator while listening either to global positioning system instructions (integrated task) or to a radio show (split task). We found that, compared with the integrated task, the split task was characterized by reduced multivariate functional connectivity between the driving and listening networks. Furthermore, the integrated information content of the two networks, predicting their joint dynamics above and beyond their independent dynamics, was high in the integrated task and zero in the split task. Finally, individual subjects’ ability to switch between high and low information integration predicted their driving performance across integrated and split tasks. This study raises the possibility that under certain conditions of daily life, a single brain may support two independent functional streams, a “functional split brain” similar to what is observed in patients with an anatomical split. PMID:27911805

Functional split brain in a driving/listening paradigm.

PubMed

Sasai, Shuntaro; Boly, Melanie; Mensen, Armand; Tononi, Giulio

2016-12-13

We often engage in two concurrent but unrelated activities, such as driving on a quiet road while listening to the radio. When we do so, does our brain split into functionally distinct entities? To address this question, we imaged brain activity with fMRI in experienced drivers engaged in a driving simulator while listening either to global positioning system instructions (integrated task) or to a radio show (split task). We found that, compared with the integrated task, the split task was characterized by reduced multivariate functional connectivity between the driving and listening networks. Furthermore, the integrated information content of the two networks, predicting their joint dynamics above and beyond their independent dynamics, was high in the integrated task and zero in the split task. Finally, individual subjects' ability to switch between high and low information integration predicted their driving performance across integrated and split tasks. This study raises the possibility that under certain conditions of daily life, a single brain may support two independent functional streams, a "functional split brain" similar to what is observed in patients with an anatomical split.

Methods for Conducting Cognitive Task Analysis for a Decision Making Task.

DTIC Science & Technology

1996-01-01

Cognitive task analysis (CTA) improves traditional task analysis procedures by analyzing the thought processes of performers while they complete a...for using these methods to conduct a CTA for domains which involve critical decision making tasks in naturalistic settings. The cognitive task analysis methods

Subliminal attention bias modification training in socially anxious individuals.

PubMed

Maoz, Keren; Abend, Rany; Fox, Nathan A; Pine, Daniel S; Bar-Haim, Yair

2013-01-01

Anxious individuals demonstrate threat-related attention biases both when threat stimuli are presented within conscious awareness and when presented below awareness threshold. Nevertheless, attention bias modification (ABM) research has rarely utilized sub-awareness protocols in an attempt to modify attention patterns and reduce anxiety. Exploring the potential of subliminal ABM is of interest, as it may target attention processes related to anxiety that are distinct from those engaged by supraliminal ABM. Here we examined the effect of a subliminal ABM training protocol on levels of social anxiety and stress vulnerability. Fifty-one socially anxious students were randomly assigned to either ABM or placebo condition, and completed a pre-training assessment, four training sessions, a social stressor task, and a post-training assessment. Results indicate that the subliminal ABM used here did not induce detectable changes in threat-related attention from pre- to post-training as measured by two independent attention tasks. Furthermore, the ABM and placebo groups did not differ on either self-reported social anxiety post-training or state anxiety following stress induction. Post-hoc auxiliary analyses suggest that ABM may be associated with smaller elevations in state anxiety during the stressor task only for participants who demonstrate attention bias toward threat at baseline. Implications and future research directions are discussed.

Subliminal attention bias modification training in socially anxious individuals

PubMed Central

Maoz, Keren; Abend, Rany; Fox, Nathan A.; Pine, Daniel S.; Bar-Haim, Yair

2013-01-01

Anxious individuals demonstrate threat-related attention biases both when threat stimuli are presented within conscious awareness and when presented below awareness threshold. Nevertheless, attention bias modification (ABM) research has rarely utilized sub-awareness protocols in an attempt to modify attention patterns and reduce anxiety. Exploring the potential of subliminal ABM is of interest, as it may target attention processes related to anxiety that are distinct from those engaged by supraliminal ABM. Here we examined the effect of a subliminal ABM training protocol on levels of social anxiety and stress vulnerability. Fifty-one socially anxious students were randomly assigned to either ABM or placebo condition, and completed a pre-training assessment, four training sessions, a social stressor task, and a post-training assessment. Results indicate that the subliminal ABM used here did not induce detectable changes in threat-related attention from pre- to post-training as measured by two independent attention tasks. Furthermore, the ABM and placebo groups did not differ on either self-reported social anxiety post-training or state anxiety following stress induction. Post-hoc auxiliary analyses suggest that ABM may be associated with smaller elevations in state anxiety during the stressor task only for participants who demonstrate attention bias toward threat at baseline. Implications and future research directions are discussed. PMID:23888138

Rewards and creative performance: a meta-analytic test of theoretically derived hypotheses.

PubMed

Byron, Kris; Khazanchi, Shalini

2012-07-01

Although many scholars and practitioners are interested in understanding how to motivate individuals to be more creative, whether and how rewards affect creativity remain unclear. We argue that the conflicting evidence may be due to differences between studies in terms of reward conditions and the context in which rewards are offered. Specifically, we examine 5 potential moderators of the rewards-creative performance relationship: (a) the reward contingency, (b) the extent to which participants are provided information about their past or current creative performance, (c) the extent to which the reward and context offer choice or impose control, (d) the extent to which the context serves to enhance task engagement, and (e) the extent to which the performance tasks are complex. Using random-effects models, we meta-analyzed 60 experimental and nonexperimental studies (including 69 independent samples) that examined the rewards-creativity relationship with children or adults. Our results suggest that creativity-contingent rewards tend to increase creative performance-and are more positively related to creative performance when individuals are given more positive, contingent, and task-focused performance feedback and are provided more choice (and are less controlled). In contrast, performance-contingent or completion-contingent rewards tend to have a slight negative effect on creative performance.

Divided attention limits perception of 3-D object shapes

PubMed Central

Scharff, Alec; Palmer, John; Moore, Cathleen M.

2013-01-01

Can one perceive multiple object shapes at once? We tested two benchmark models of object shape perception under divided attention: an unlimited-capacity and a fixed-capacity model. Under unlimited-capacity models, shapes are analyzed independently and in parallel. Under fixed-capacity models, shapes are processed at a fixed rate (as in a serial model). To distinguish these models, we compared conditions in which observers were presented with simultaneous or sequential presentations of a fixed number of objects (The extended simultaneous-sequential method: Scharff, Palmer, & Moore, 2011a, 2011b). We used novel physical objects as stimuli, minimizing the role of semantic categorization in the task. Observers searched for a specific object among similar objects. We ensured that non-shape stimulus properties such as color and texture could not be used to complete the task. Unpredictable viewing angles were used to preclude image-matching strategies. The results rejected unlimited-capacity models for object shape perception and were consistent with the predictions of a fixed-capacity model. In contrast, a task that required observers to recognize 2-D shapes with predictable viewing angles yielded an unlimited capacity result. Further experiments ruled out alternative explanations for the capacity limit, leading us to conclude that there is a fixed-capacity limit on the ability to perceive 3-D object shapes. PMID:23404158

A systematic investigation of the link between rational number processing and algebra ability.

PubMed

Hurst, Michelle; Cordes, Sara

2018-02-01

Recent research suggests that fraction understanding is predictive of algebra ability; however, the relative contributions of various aspects of rational number knowledge are unclear. Furthermore, whether this relationship is notation-dependent or rather relies upon a general understanding of rational numbers (independent of notation) is an open question. In this study, college students completed a rational number magnitude task, procedural arithmetic tasks in fraction and decimal notation, and an algebra assessment. Using these tasks, we measured three different aspects of rational number ability in both fraction and decimal notation: (1) acuity of underlying magnitude representations, (2) fluency with which symbols are mapped to the underlying magnitudes, and (3) fluency with arithmetic procedures. Analyses reveal that when looking at the measures of magnitude understanding, the relationship between adults' rational number magnitude performance and algebra ability is dependent upon notation. However, once performance on arithmetic measures is included in the relationship, individual measures of magnitude understanding are no longer unique predictors of algebra performance. Furthermore, when including all measures simultaneously, results revealed that arithmetic fluency in both fraction and decimal notation each uniquely predicted algebra ability. Findings are the first to demonstrate a relationship between rational number understanding and algebra ability in adults while providing a clearer picture of the nature of this relationship. © 2017 The British Psychological Society.

Comparison of functional network connectivity for passive-listening and active-response narrative comprehension in adolescents.

PubMed

Wang, Yingying; Holland, Scott K

2014-05-01

Comprehension of narrative stories plays an important role in the development of language skills. In this study, we compared brain activity elicited by a passive-listening version and an active-response (AR) version of a narrative comprehension task by using independent component (IC) analysis on functional magnetic resonance imaging data from 21 adolescents (ages 14-18 years). Furthermore, we explored differences in functional network connectivity engaged by two versions of the task and investigated the relationship between the online response time and the strength of connectivity between each pair of ICs. Despite similar brain region involvements in auditory, temporoparietal, and frontoparietal language networks for both versions, the AR version engages some additional network elements including the left dorsolateral prefrontal, anterior cingulate, and sensorimotor networks. These additional involvements are likely associated with working memory and maintenance of attention, which can be attributed to the differences in cognitive strategic aspects of the two versions. We found significant positive correlation between the online response time and the strength of connectivity between an IC in left inferior frontal region and an IC in sensorimotor region. An explanation for this finding is that longer reaction time indicates stronger connection between the frontal and sensorimotor networks caused by increased activation in adolescents who require more effort to complete the task.

Comparison of the Effects of Continuous Video Modeling, Video Prompting, and Video Modeling on Task Completion by Young Adults with Moderate Intellectual Disability

ERIC Educational Resources Information Center

Mechling, Linda C.; Ayres, Kevin M.; Bryant, Kathryn J.; Foster, Ashley L.

2014-01-01

This study compared the effects of three procedures (video prompting: VP, video modeling: VM, and continuous video modeling: CVM) on task completion by three high school students with moderate intellectual disability. The comparison was made across three sets of fundamentally different tasks (putting away household items in clusters of two items;…

Effects of Creative and Non-Creative Work on the Tendency To Drink Alcohol during the Restitution Phase of the Creative Process.

ERIC Educational Resources Information Center

Gustafson, Roland; Norlander, Torsten

1995-01-01

This study examined how type of task affected 42 subjects' drinking patterns. Results indicated that subjects who had completed light creative work drank more alcohol than those in noncreative tasks, and participants completing hard creative tasks drank more of both alcoholic and nonalcoholic fluids. Results are discussed in terms of the need to…

Experimentally-induced learned helplessness in adolescents with type 1 diabetes.

PubMed

McLaughlin, Elizabeth; Lefaivre, Marie-josée; Cummings, Elizabeth

2010-05-01

To determine whether adolescents with type 1 diabetes are more at risk for learned helplessness than their healthy peers. Twenty-three adolescents with diabetes and 25 controls completed a solvable or unsolvable concept formation task. All completed pre- and post-task performance and attribution ratings, and later completed an anagram-solving task to determine if perceived helplessness on the first task would negatively impact performance on the second. Participants in the unsolvable condition solved fewer anagrams; those with diabetes did not show weaker performance than controls. Participants in the solvable condition (diabetes and controls) showed an increase in internal attributions from before the concept formation task to after. In the unsolvable condition, only participants with diabetes made more external attributions for their failure. Contrary to the only other controlled study to use this paradigm in youth with chronic illness, adolescents with diabetes were not more susceptible to learned helplessness.

Single-task and dual-task tandem gait test performance after concussion.

PubMed

Howell, David R; Osternig, Louis R; Chou, Li-Shan

2017-07-01

To compare single-task and dual-task tandem gait test performance between athletes after concussion with controls on observer-timed, spatio-temporal, and center-of-mass (COM) balance control measurements. Ten participants (19.0±5.5years) were prospectively identified and completed a tandem gait test protocol within 72h of concussion and again 1 week, 2 weeks, 1 month, and 2 months post-injury. Seven uninjured controls (20.0±4.5years) completed the same protocol in similar time increments. Tandem gait test trials were performed with (dual-task) and without (single-task) concurrently performing a cognitive test as whole-body motion analysis was performed. Outcome variables included test completion time, average tandem gait velocity, cadence, and whole-body COM frontal plane displacement. Concussion participants took significantly longer to complete the dual-task tandem gait test than controls throughout the first 2 weeks post-injury (mean time=16.4 [95% CI: 13.4-19.4] vs. 10.1 [95% CI: 6.4-13.7] seconds; p=0.03). Single-task tandem gait times were significantly lower 72h post-injury (p=0.04). Dual-task cadence was significantly lower for concussion participants than controls (89.5 [95% CI: 68.6-110.4] vs. 127.0 [95% CI: 97.4-156.6] steps/minute; p=0.04). Moderately-high to high correlations between tandem gait test time and whole-body COM medial-lateral displacement were detected at each time point during dual-task gait (r s =0.70-0.93; p=0.03-0.001). Adding a cognitive task during the tandem gait test resulted in longer detectable deficits post-concussion compared to the traditional single-task tandem gait test. As a clinical tool to assess dynamic motor function, tandem gait may assist with return to sport decisions after concussion. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Improving older adults' memory performance using prior task success.

PubMed

Geraci, Lisa; Miller, Tyler M

2013-06-01

Holding negative aging stereotypes can lead older adults to perform poorly on memory tests. We attempted to improve older adults' memory performance by giving them task experience that would counter their negative performance expectations. Before participating in a memory experiment, younger and older adults were given a cognitive task that they could either successfully complete, not successfully complete, or they were given no prior task. For older adults, recall was significantly higher and self-reported anxiety was significantly lower for the prior task success group relative to the other groups. There was no effect of prior task experience on younger adults' memory performance. Results suggest that older adults' memory can be improved with a single successful prior task experience. PsycINFO Database Record (c) 2013 APA, all rights reserved.

How Do You Like Your Science, Wet or Dry? How Two Lab Experiences Influence Student Understanding of Science Concepts and Perceptions of Authentic Scientific Practice.

PubMed

Munn, Maureen; Knuth, Randy; Van Horne, Katie; Shouse, Andrew W; Levias, Sheldon

2017-01-01

This study examines how two kinds of authentic research experiences related to smoking behavior-genotyping human DNA (wet lab) and using a database to test hypotheses about factors that affect smoking behavior (dry lab)-influence students' perceptions and understanding of scientific research and related science concepts. The study used pre and post surveys and a focus group protocol to compare students who conducted the research experiences in one of two sequences: genotyping before database and database before genotyping. Students rated the genotyping experiment to be more like real science than the database experiment, in spite of the fact that they associated more scientific tasks with the database experience than genotyping. Independent of the order of completing the labs, students showed gains in their understanding of science concepts after completion of the two experiences. There was little change in students' attitudes toward science pre to post, as measured by the Scientific Attitude Inventory II. However, on the basis of their responses during focus groups, students developed more sophisticated views about the practices and nature of science after they had completed both research experiences, independent of the order in which they experienced them. © 2017 M. Munn et al. CBE—Life Sciences Education © 2017 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Defining the subjective experience of workload

NASA Technical Reports Server (NTRS)

Hart, S. G.; Childress, M. E.; Bortolussi, M.

1981-01-01

Flight scenarios that represent different types and levels of pilot workload are needed in order to conduct research about, and develop measures of, pilot workload. In order to be useful, however, the workload associated with such scenarios and the component tasks must be determined independently. An initial study designed to provide such information was conducted by asking a panel of general aviation pilots to evaluate flight-related tasks for the overall, perceptual, physical, and cognitive workload they impose. These ratings will provide the nucleus for a data base of flight-related primary tasks that have been independently rated for workload to use in workload assessment research.

Early Visual Word Processing Is Flexible: Evidence from Spatiotemporal Brain Dynamics.

PubMed

Chen, Yuanyuan; Davis, Matthew H; Pulvermüller, Friedemann; Hauk, Olaf

2015-09-01

Visual word recognition is often described as automatic, but the functional locus of top-down effects is still a matter of debate. Do task demands modulate how information is retrieved, or only how it is used? We used EEG/MEG recordings to assess whether, when, and how task contexts modify early retrieval of specific psycholinguistic information in occipitotemporal cortex, an area likely to contribute to early stages of visual word processing. Using a parametric approach, we analyzed the spatiotemporal response patterns of occipitotemporal cortex for orthographic, lexical, and semantic variables in three psycholinguistic tasks: silent reading, lexical decision, and semantic decision. Task modulation of word frequency and imageability effects occurred simultaneously in ventral occipitotemporal regions-in the vicinity of the putative visual word form area-around 160 msec, following task effects on orthographic typicality around 100 msec. Frequency and typicality also produced task-independent effects in anterior temporal lobe regions after 200 msec. The early task modulation for several specific psycholinguistic variables indicates that occipitotemporal areas integrate perceptual input with prior knowledge in a task-dependent manner. Still, later task-independent effects in anterior temporal lobes suggest that word recognition eventually leads to retrieval of semantic information irrespective of task demands. We conclude that even a highly overlearned visual task like word recognition should be described as flexible rather than automatic.

Independent Research and Independent Exploratory Development at the Navy Personnel Research and Development Center--Fiscal Year 1984.

DTIC Science & Technology

1985-04-01

decision aids consider the cognitive skills of human operators. Data are required on the kinds of decision strategies they invoke, their limitations in...basic electronics, memory for procedural tasks, and career-role learning by officers. Computerized decision aids for surveillance tasks and opportunities...of Navy retention incentives. Computerized aids for plain English in military documents and for tactical action officer training were also developed in

Feature bindings endure without attention: evidence from an explicit recall task.

PubMed

Gajewski, Daniel A; Brockmole, James R

2006-08-01

Are integrated objects the unit of capacity of visual working memory, or is continued attention needed to maintain bindings between independently stored features? In a delayed recall task, participants reported the color and shape of a probed item from a memory array. During the delay, attention was manipulated with an exogenous cue. Recall was elevated at validly cued positions, indicating that the cue affected item memory. On invalid trials, participants most frequently recalled either both features (perfect object memory) or neither of the two features (no object memory); the frequency with which only one feature was recalled was significantly lower than predicted by feature independence as determined in a single-feature recall task. These data do not support the view that features are remembered independently when attention is withdrawn. Instead, integrated objects are stored in visual working memory without need for continued attention.

Vehicle automation: a remedy for driver stress?

PubMed

Funke, G; Matthews, G; Warm, J S; Emo, A K

2007-08-01

The present study addressed the effects of stress, vehicle automation and subjective state on driver performance and mood in a simulated driving task. A total of 168 college students participated. Participants in the stress-induction condition completed a 'winter' drive, which included periodic loss of control episodes. Participants in the no-stress-induction condition were not exposed to loss of control. An additional, independent manipulation of vehicle speed was also conducted, consisting of two control conditions requiring manual speed regulation and a third in which vehicle speed was automatically regulated by the simulation. Stress and automation both influenced subjective distress, but the two factors did not interact. Driver performance data indicated that vehicle automation impacted performance similarly in the stress and no-stress conditions. Individual differences in subjective stress response and performance were also investigated. Resource theory provides a framework that partially but not completely explains the relationship between vehicle automation and driver stress. Implications for driver workload, safety and training are discussed.

76 FR 55394 - Meeting of the Task Force on Community Preventive Services

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-07

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention Meeting of the...), Department of Health and Human Services (HHS). ACTION: Notice of meeting. SUMMARY: The Centers for Disease... (Task Force). The Task Force--an independent, nonfederal body of nationally known leaders in public...

76 FR 4115 - Meeting of the Task Force on Community Preventive Services

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-24

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention Meeting of the...), Department of Health and Human Services (HHS). ACTION: Notice of meeting. SUMMARY: The Centers for Disease... (Task Force). The Task Force--an independent, nonfederal body of nationally known leaders in public...

75 FR 63846 - Meeting of the Task Force on Community Preventive Services

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-18

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention Meeting of the...), Department of Health and Human Services (HHS). ACTION: Notice of meeting. SUMMARY: The Centers for Disease... (Task Force). The Task Force is an independent, nonfederal body of nationally known leaders in public...

Open angle glaucoma effects on preattentive visual search efficiency for flicker, motion displacement and orientation pop-out tasks.

PubMed

Loughman, James; Davison, Peter; Flitcroft, Ian

2007-11-01

Preattentive visual search (PAVS) describes rapid and efficient retinal and neural processing capable of immediate target detection in the visual field. Damage to the nerve fibre layer or visual pathway might reduce the efficiency with which the visual system performs such analysis. The purpose of this study was to test the hypothesis that patients with glaucoma are impaired on parallel search tasks, and that this would serve to distinguish glaucoma in early cases. Three groups of observers (glaucoma patients, suspect and normal individuals) were examined, using computer-generated flicker, orientation, and vertical motion displacement targets to assess PAVS efficiency. The task required rapid and accurate localisation of a singularity embedded in a field of 119 homogeneous distractors on either the left or right-hand side of a computer monitor. All subjects also completed a choice reaction time (CRT) task. Independent sample T tests revealed PAVS efficiency to be significantly impaired in the glaucoma group compared with both normal and suspect individuals. Performance was impaired in all types of glaucoma tested. Analysis between normal and suspect individuals revealed a significant difference only for motion displacement response times. Similar analysis using a PAVS/CRT index confirmed the glaucoma findings but also showed statistically significant differences between suspect and normal individuals across all target types. A test of PAVS efficiency appears capable of differentiating early glaucoma from both normal and suspect cases. Analysis incorporating a PAVS/CRT index enhances the diagnostic capacity to differentiate normal from suspect cases.

Pain Anxiety and Its Association With Pain Congruence Trajectories During the Cold Pressor Task.

PubMed

Clark, Shannon M; Cano, Annmarie; Goubert, Liesbet; Vlaeyen, Johan W S; Wurm, Lee H; Corley, Angelia M

2017-04-01

Incongruence of pain severity ratings among people experiencing pain and their observers has been linked to psychological distress. Previous studies have measured pain rating congruence through static self-report, involving a single rating of pain; however, this method does not capture changes in ratings over time. The present study examined the extent to which partners were congruent on multiple ratings of a participants' pain severity during the cold pressor task. Furthermore, 2 components of pain anxiety-pain catastrophizing and perceived threat-were examined as predictors of pain congruence. Undergraduate couples in a romantic relationship (N = 127 dyads) participated in this study. Both partners completed measures of pain catastrophizing and perceived threat before randomization to their cold pressor participant or observer roles. Participants and observers rated the participant's pain in writing several times over the course of the task. On average, observers rated participants' pain as less severe than participants' rated their own pain. In addition, congruence between partners increased over time because of observers' ratings becoming more similar to participant's ratings. Finally, pain catastrophizing and perceived threat independently and jointly influenced the degree to which partners similarly rated the participant's pain. This article presents a novel application of the cold pressor task to show that pain rating congruence among romantic partners changes over time. These findings indicate that pain congruence is not static and is subject to pain anxiety in both partners. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

Effects of fear of falling and activity restriction on normal and dual task walking in community dwelling older adults.

PubMed

Donoghue, Orna A; Cronin, Hilary; Savva, George M; O'Regan, Claire; Kenny, Rose Anne

2013-05-01

Fear of falling (FOF) is associated with poor physical and psychosocial health and can have debilitating consequences especially when it leads to activity restriction. This study examined whether normal and dual task gait disruptions were independently associated with FOF and activity restriction or if they were fully explained by impaired health status. Data was obtained from The Irish Longitudinal Study on Ageing (TILDA). Community dwelling adults ≥65 years, with a Mini-Mental State Examination score ≥18 and who completed a gait assessment (n=1307) were divided into three groups: no FOF, FOF but no activity restriction (FOF-NAR), FOF with activity restriction (FOF-AR). Physical, psychosocial and cognitive measures were obtained and gait characteristics were assessed using a GAITRite(®) mat during normal and dual task (cognitive) walking. After adjusting for sociodemographics, physical, mental and cognitive health, FOF was associated with reduced gait speed and stride length and increased double support phase and step width in normal and dual task conditions; these changes were most pronounced in those who restrict activities as a result of FOF. These gait changes may be associated with an increased fall risk, however some changes especially increased step width may also reflect positive, compensatory adaptations to FOF. The results also highlight the importance of treating underlying health impairments and preventing the transition from FOF to activity restriction. Copyright © 2012 Elsevier B.V. All rights reserved.

Measuring language lateralisation with different language tasks: a systematic review

PubMed Central

Thompson, Paul A.; Wilson, Alexander C.; Bishop, Dorothy V.M.; Woodhead, Zoe V.J.

2017-01-01

Language lateralisation refers to the phenomenon in which one hemisphere (typically the left) shows greater involvement in language functions than the other. Measurement of laterality is of interest both to researchers investigating the neural organisation of the language system and to clinicians needing to establish an individual’s hemispheric dominance for language prior to surgery, as in patients with intractable epilepsy. Recently, there has been increasing awareness of the possibility that different language processes may develop hemispheric lateralisation independently, and to varying degrees. However, it is not always clear whether differences in laterality across language tasks with fMRI are reflective of meaningful variation in hemispheric lateralisation, or simply of trivial methodological differences between paradigms. This systematic review aims to assess different language tasks in terms of the strength, reliability and robustness of the laterality measurements they yield with fMRI, to look at variability that is both dependent and independent of aspects of study design, such as the baseline task, region of interest, and modality of the stimuli. Recommendations are made that can be used to guide task design; however, this review predominantly highlights that the current high level of methodological variability in language paradigms prevents conclusions as to how different language functions may lateralise independently. We conclude with suggestions for future research using tasks that engage distinct aspects of language functioning, whilst being closely matched on non-linguistic aspects of task design (e.g., stimuli, task timings etc); such research could produce more reliable and conclusive insights into language lateralisation. This systematic review was registered as a protocol on Open Science Framework: https://osf.io/5vmpt/. PMID:29085748

Cross-domain and multi-task transfer learning of deep convolutional neural network for breast cancer diagnosis in digital breast tomosynthesis

NASA Astrophysics Data System (ADS)

Samala, Ravi K.; Chan, Heang-Ping; Hadjiiski, Lubomir; Helvie, Mark A.; Richter, Caleb; Cha, Kenny

2018-02-01

We propose a cross-domain, multi-task transfer learning framework to transfer knowledge learned from non-medical images by a deep convolutional neural network (DCNN) to medical image recognition task while improving the generalization by multi-task learning of auxiliary tasks. A first stage cross-domain transfer learning was initiated from ImageNet trained DCNN to mammography trained DCNN. 19,632 regions-of-interest (ROI) from 2,454 mass lesions were collected from two imaging modalities: digitized-screen film mammography (SFM) and full-field digital mammography (DM), and split into training and test sets. In the multi-task transfer learning, the DCNN learned the mass classification task simultaneously from the training set of SFM and DM. The best transfer network for mammography was selected from three transfer networks with different number of convolutional layers frozen. The performance of single-task and multitask transfer learning on an independent SFM test set in terms of the area under the receiver operating characteristic curve (AUC) was 0.78+/-0.02 and 0.82+/-0.02, respectively. In the second stage cross-domain transfer learning, a set of 12,680 ROIs from 317 mass lesions on DBT were split into validation and independent test sets. We first studied the data requirements for the first stage mammography trained DCNN by varying the mammography training data from 1% to 100% and evaluated its learning on the DBT validation set in inference mode. We found that the entire available mammography set provided the best generalization. The DBT validation set was then used to train only the last four fully connected layers, resulting in an AUC of 0.90+/-0.04 on the independent DBT test set.

Probing quantum state space: does one have to learn everything to learn something?

PubMed

Carmeli, Claudio; Heinosaari, Teiko; Schultz, Jussi; Toigo, Alessandro

2017-05-01

Determining the state of a quantum system is a consuming procedure. For this reason, whenever one is interested only in some particular property of a state, it would be desirable to design a measurement set-up that reveals this property with as little effort as possible. Here, we investigate whether, in order to successfully complete a given task of this kind, one needs an informationally complete measurement, or if something less demanding would suffice. The first alternative means that in order to complete the task, one needs a measurement which fully determines the state. We formulate the task as a membership problem related to a partitioning of the quantum state space and, in doing so, connect it to the geometry of the state space. For a general membership problem, we prove various sufficient criteria that force informational completeness, and we explicitly treat several physically relevant examples. For the specific cases that do not require informational completeness, we also determine bounds on the minimal number of measurement outcomes needed to ensure success in the task.

Probing quantum state space: does one have to learn everything to learn something?

PubMed Central

Carmeli, Claudio; Schultz, Jussi; Toigo, Alessandro

2017-01-01

Determining the state of a quantum system is a consuming procedure. For this reason, whenever one is interested only in some particular property of a state, it would be desirable to design a measurement set-up that reveals this property with as little effort as possible. Here, we investigate whether, in order to successfully complete a given task of this kind, one needs an informationally complete measurement, or if something less demanding would suffice. The first alternative means that in order to complete the task, one needs a measurement which fully determines the state. We formulate the task as a membership problem related to a partitioning of the quantum state space and, in doing so, connect it to the geometry of the state space. For a general membership problem, we prove various sufficient criteria that force informational completeness, and we explicitly treat several physically relevant examples. For the specific cases that do not require informational completeness, we also determine bounds on the minimal number of measurement outcomes needed to ensure success in the task. PMID:28588404

Augmented Reality versus Virtual Reality for 3D Object Manipulation.

PubMed

Krichenbauer, Max; Yamamoto, Goshiro; Taketom, Takafumi; Sandor, Christian; Kato, Hirokazu

2018-02-01

Virtual Reality (VR) Head-Mounted Displays (HMDs) are on the verge of becoming commodity hardware available to the average user and feasible to use as a tool for 3D work. Some HMDs include front-facing cameras, enabling Augmented Reality (AR) functionality. Apart from avoiding collisions with the environment, interaction with virtual objects may also be affected by seeing the real environment. However, whether these effects are positive or negative has not yet been studied extensively. For most tasks it is unknown whether AR has any advantage over VR. In this work we present the results of a user study in which we compared user performance measured in task completion time on a 9 degrees of freedom object selection and transformation task performed either in AR or VR, both with a 3D input device and a mouse. Our results show faster task completion time in AR over VR. When using a 3D input device, a purely VR environment increased task completion time by 22.5 percent on average compared to AR ( ). Surprisingly, a similar effect occurred when using a mouse: users were about 17.3 percent slower in VR than in AR ( ). Mouse and 3D input device produced similar task completion times in each condition (AR or VR) respectively. We further found no differences in reported comfort.

Modifications to Optimize the AH-1Z Human Machine Interface

DTIC Science & Technology

2013-04-18

accomplish this, a complete workload study of tasks performed by aircrew in the AH-1Z must be completed in the near future in order to understand...design flaws and guide future design and integration of increased capability. Additionally, employment of material solutions to provide aircrew with the...accomplish this, a complete workload study of tasks performed by aircrew in the AH-1Z must be completed in the near future in order to understand

The Independent School Experience: Aspects of the Normative Environments of Single-Sex and Coed Secondary Schools.

ERIC Educational Resources Information Center

Trickett, Edison J.; And Others

1982-01-01

The normative environments of single-sex independent schools were found to be more academic, with greater task and competition orientation, than coeducational independent schools. Representative independent schools were compared to each other and to public schools with a discussion of learning involvement, function, purpose, and student and…

The effects of audibility and novel word learning ability on vocabulary level in children with cochlear implants.

PubMed

Davidson, Lisa S; Geers, Ann E; Nicholas, Johanna G

2014-07-01

A novel word learning (NWL) paradigm was used to explore underlying phonological and cognitive mechanisms responsible for delayed vocabulary level in children with cochlear implants (CIs). One hundred and one children using CIs, 6-12 years old, were tested along with 47 children with normal hearing (NH). Tests of NWL, receptive vocabulary, and speech perception at 2 loudness levels were administered to children with CIs. Those with NH completed the NWL task and a receptive vocabulary test. CI participants with good audibility (GA) versus poor audibility (PA) were compared on all measures. Analysis of variance was used to compare performance across the children with NH and the two groups of children with CIs. Multiple regression analysis was employed to identify independent predictors of vocabulary outcomes. Children with CIs in the GA group scored higher in receptive vocabulary and NWL than children in the PA group, although they did not reach NH levels. CI-aided pure tone threshold and performance on the NWL task predicted independent variance in vocabulary after accounting for other known predictors. Acquiring spoken vocabulary is facilitated by GA with a CI and phonological learning and memory skills. Children with CIs did not learn novel words at the same rate or achieve the same receptive vocabulary levels as their NH peers. Maximizing audibility for the perception of speech and direct instruction of new vocabulary may be necessary for children with CIs to reach levels seen in peers with NH.

Independent Associations Between Sedentary Behaviors and Mental, Cognitive, Physical, and Functional Health Among Older Adults in Retirement Communities.

PubMed

Rosenberg, Dori E; Bellettiere, John; Gardiner, Paul A; Villarreal, Veronica N; Crist, Katie; Kerr, Jacqueline

2016-01-01

We examined the relationships between objective and self-reported sedentary time and health indicators among older adults residing in retirement communities. Our cross-sectional analysis used data from 307 participants who completed baseline measurements of a physical activity trial in 11 retirement communities in San Diego County. Sedentary time was objectively measured with devices (accelerometers) and using self-reports. Outcomes assessed included emotional and cognitive health, physical function, and physical health (eg, blood pressure). Linear mixed-effects models examined associations between sedentary behavior and outcomes adjusting for demographics and accelerometer physical activity. Higher device-measured sedentary time was associated with worse objective physical function (Short Physical Performance Battery, balance task scores, 400-m walk time, chair stand time, gait speed), self-reported physical function, and fear of falling but with less sleep disturbance (all ps < .05). TV viewing was positively related to 400-m walk time (p < .05). Self-reported sedentary behavior was related to better performance on one cognitive task (trails A; p < .05). Sedentary time was mostly related to poorer physical function independently of moderate-to-vigorous physical activity and may be a modifiable behavior target in interventions aiming to improve physical function in older adults. Few associations were observed with self-reported sedentary behavior measures. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Early differential processing of material images: Evidence from ERP classification.

PubMed

Wiebel, Christiane B; Valsecchi, Matteo; Gegenfurtner, Karl R

2014-06-24

Investigating the temporal dynamics of natural image processing using event-related potentials (ERPs) has a long tradition in object recognition research. In a classical Go-NoGo task two characteristic effects have been emphasized: an early task independent category effect and a later task-dependent target effect. Here, we set out to use this well-established Go-NoGo paradigm to study the time course of material categorization. Material perception has gained more and more interest over the years as its importance in natural viewing conditions has been ignored for a long time. In addition to analyzing standard ERPs, we conducted a single trial ERP pattern analysis. To validate this procedure, we also measured ERPs in two object categories (people and animals). Our linear classification procedure was able to largely capture the overall pattern of results from the canonical analysis of the ERPs and even extend it. We replicate the known target effect (differential Go-NoGo potential at frontal sites) for the material images. Furthermore, we observe task-independent differential activity between the two material categories as early as 140 ms after stimulus onset. Using our linear classification approach, we show that material categories can be differentiated consistently based on the ERP pattern in single trials around 100 ms after stimulus onset, independent of the target-related status. This strengthens the idea of early differential visual processing of material categories independent of the task, probably due to differences in low-level image properties and suggests pattern classification of ERP topographies as a strong instrument for investigating electrophysiological brain activity. © 2014 ARVO.

Impact of induced joy on literacy in children: does the nature of the task make a difference?

PubMed

Tornare, Elise; Cuisinier, Frédérique; Czajkowski, Nikolai O; Pons, Francisco

2017-04-01

This research examined whether induced joy influences fifth graders' performance in literacy tasks. Children were asked to recall a joyful experience, used as a joy induction, before completing either a grammar (Study 1) or textual comprehension task (Study 2). The grammar task involved understanding at the surface level and retrieval of appropriate declarative and procedural knowledge, but limited elaboration unlike the textual comprehension task, which tackled inference generation. By differentiating tasks based on depth of processing required for completion we aimed at testing the validity of two concurrent hypotheses: that of a facilitating effect and that of a detrimental effect of induced joy. Compared to controls, joy induced children showed better performance on the grammar task - specifically children with lower language ability. No differences across groups emerged as a function of joy induction on the text comprehension task. Results are discussed with respect to emotion effects on cognition.

What Do We Really Know about Cognitive Inhibition? Task Demands and Inhibitory Effects across a Range of Memory and Behavioural Tasks

PubMed Central

Noreen, Saima; MacLeod, Malcolm D.

2015-01-01

Our study explores inhibitory control across a range of widely recognised memory and behavioural tasks. Eighty-seven never-depressed participants completed a series of tasks designed to measure inhibitory control in memory and behaviour. Specifically, a variant of the selective retrieval-practice and the Think/No-Think tasks were employed as measures of memory inhibition. The Stroop-Colour Naming and the Go/No-Go tasks were used as measures of behavioural inhibition. Participants completed all 4 tasks. Task presentation order was counterbalanced across 3 separate testing sessions for each participant. Standard inhibitory forgetting effects emerged on both memory tasks but the extent of forgetting across these tasks was not correlated. Furthermore, there was no relationship between memory inhibition tasks and either of the main behavioural inhibition measures. At a time when cognitive inhibition continues to gain acceptance as an explanatory mechanism, our study raises fundamental questions about what we actually know about inhibition and how it is affected by the processing demands of particular inhibitory tasks. PMID:26270470

The relation of locus-of-control orientation and task structure to problem-solving performance of sixth-grade student pairs

NASA Astrophysics Data System (ADS)

Main, June Dewey; Budd Rowe, Mary

This study investigated the relationship of locus-of-control orientations and task structure to the science problem-solving performance of 100 same-sex, sixth-grade student pairs. Pairs performed a four-variable problem-solving task, racing cylinders down a ramp in a series of trials to determine the 3 fastest of 18 different cylinders. The task was completed in one of two treatment conditions: the structured condition with moderate cuing and the unstructured condition with minimal cuing. Pairs completed an after-task assessment, predicting the results of proposed cylinder races, to measure the ability to understand and apply task concepts. Overall conclusions were: (1) There was no relationship between locus-of-control orientation and effectiveness of problem-solving strategy; (2) internality was significantly related to higher accuracy on task solutions and on after-task predictions; (3) there was no significant relationship between task structure and effectiveness of problem-solving strategy; (4) solutions to the task were more accurate in the unstructured task condition; (5) internality related to more accurate solutions in the unstructured task condition.

What Do We Really Know about Cognitive Inhibition? Task Demands and Inhibitory Effects across a Range of Memory and Behavioural Tasks.

PubMed

Noreen, Saima; MacLeod, Malcolm D

2015-01-01

Our study explores inhibitory control across a range of widely recognised memory and behavioural tasks. Eighty-seven never-depressed participants completed a series of tasks designed to measure inhibitory control in memory and behaviour. Specifically, a variant of the selective retrieval-practice and the Think/No-Think tasks were employed as measures of memory inhibition. The Stroop-Colour Naming and the Go/No-Go tasks were used as measures of behavioural inhibition. Participants completed all 4 tasks. Task presentation order was counterbalanced across 3 separate testing sessions for each participant. Standard inhibitory forgetting effects emerged on both memory tasks but the extent of forgetting across these tasks was not correlated. Furthermore, there was no relationship between memory inhibition tasks and either of the main behavioural inhibition measures. At a time when cognitive inhibition continues to gain acceptance as an explanatory mechanism, our study raises fundamental questions about what we actually know about inhibition and how it is affected by the processing demands of particular inhibitory tasks.

Are Current Insulin Pumps Accessible to Blind and Visually Impaired People?

PubMed Central

Burton, Darren M.; Uslan, Mark M.; Blubaugh, Morgan V.; Clements, Charles W.

2009-01-01

Background In 2004, Uslan and colleagues determined that insulin pumps (IPs) on the market were largely inaccessible to blind and visually impaired persons. The objective of this study is to determine if accessibility status changed in the ensuing 4 years. Methods Five IPs on the market in 2008 were acquired and analyzed for key accessibility traits such as speech and other audio output, tactual nature of control buttons, and the quality of visual displays. It was also determined whether or not a blind or visually impaired person could independently complete tasks such as programming the IP for insulin delivery, replacing batteries, and reading manuals and other documentation. Results It was found that IPs have not improved in accessibility since 2004. None have speech output, and with the exception of the Animas IR 2020, no significantly improved visual display characteristics were found. Documentation is still not completely accessible. Conclusion Insulin pumps are relatively complex devices, with serious health consequences resulting from improper use. For IPs to be used safely and independently by blind and visually impaired patients, they must include voice output to communicate all the information presented on their display screens. Enhancing display contrast and the size of the displayed information would also improve accessibility for visually impaired users. The IPs must also come with accessible user documentation in alternate formats. PMID:20144301

Are current insulin pumps accessible to blind and visually impaired people?

PubMed

Burton, Darren M; Uslan, Mark M; Blubaugh, Morgan V; Clements, Charles W

2009-05-01

In 2004, Uslan and colleagues determined that insulin pumps (IPs) on the market were largely inaccessible to blind and visually impaired persons. The objective of this study is to determine if accessibility status changed in the ensuing 4 years. Five IPs on the market in 2008 were acquired and analyzed for key accessibility traits such as speech and other audio output, tactual nature of control buttons, and the quality of visual displays. It was also determined whether or not a blind or visually impaired person could independently complete tasks such as programming the IP for insulin delivery, replacing batteries, and reading manuals and other documentation. It was found that IPs have not improved in accessibility since 2004. None have speech output, and with the exception of the Animas IR 2020, no significantly improved visual display characteristics were found. Documentation is still not completely accessible. Insulin pumps are relatively complex devices, with serious health consequences resulting from improper use. For IPs to be used safely and independently by blind and visually impaired patients, they must include voice output to communicate all the information presented on their display screens. Enhancing display contrast and the size of the displayed information would also improve accessibility for visually impaired users. The IPs must also come with accessible user documentation in alternate formats. 2009 Diabetes Technology Society.

Factors contributing to nursing task incompletion as perceived by nurses working in Kuwait general hospitals.

PubMed

Al-Kandari, Fatimah; Thomas, Deepa

2009-12-01

Unfinished care has a strong relationship with quality of nursing care. Most issues related to tasks incompletion arise from staffing and workload. This study was conducted to assess the workload of nurses, the nursing activities (tasks) nurses commonly performed on medical and surgical wards, elements of nursing care activities left incomplete by nurses during a shift, factors contributing to task incompletion and the relationship between staffing, demographic variables and task incompletion. Exploratory survey using a self-administered questionnaire developed from IHOC survey, USA. All full time registered nurses working on the general medical and surgical wards of five government general hospitals in Kuwait. Research assistants distributed and collected back the questionnaires. Four working days were given to participants to complete and return the questionnaires. A total of 820 questionnaires were distributed and 95% were returned. Descriptive and inferential analysis using SPSS-11. The five most frequently performed nursing activities were: administration of medications, assessing patient condition, preparing/updating nursing care plans, close patient monitoring and client health teaching. The most common nursing activities nurses were unable to complete were: comfort talk with patient and family, adequate documentation of nursing care, oral hygiene, routine catheter care and starting or changing IV fluid on time. Tasks were more complete when the nurse-patient load was less than 5. Nurses' age and educational background influenced task completion while nurses' gender had no influence on it. Increased patient loads, resulting in increased frequency of nursing tasks and non-nursing tasks, were positively correlated to incompletion of nursing activities during the shift. Emphasis should be given to maintaining the optimum nurse-patient load and decreasing the non-nursing workload of nurses to enhance the quality of nursing care.

Evaluation of a novel Serious Game based assessment tool for patients with Alzheimer's disease.

PubMed

Vallejo, Vanessa; Wyss, Patric; Rampa, Luca; Mitache, Andrei V; Müri, René M; Mosimann, Urs P; Nef, Tobias

2017-01-01

Despite growing interest in developing ecological assessment of difficulties in patients with Alzheimer's disease new methods assessing the cognitive difficulties related to functional activities are missing. To complete current evaluation, the use of Serious Games can be a promising approach as it offers the possibility to recreate a virtual environment with daily living activities and a precise and complete cognitive evaluation. The aim of the present study was to evaluate the usability and the screening potential of a new ecological tool for assessment of cognitive functions in patients with Alzheimer's disease. Eighteen patients with Alzheimer's disease and twenty healthy controls participated to the study. They were asked to complete six daily living virtual tasks assessing several cognitive functions: three navigation tasks, one shopping task, one cooking task and one table preparation task following a one-day scenario. Usability of the game was evaluated through a questionnaire and through the analysis of the computer interactions for the two groups. Furthermore, the performances in terms of time to achieve the task and percentage of completion on the several tasks were recorded. Results indicate that both groups subjectively found the game user friendly and they were objectively able to play the game without computer interactions difficulties. Comparison of the performances between the two groups indicated a significant difference in terms of percentage of achievement of the several tasks and in terms of time they needed to achieve the several tasks. This study suggests that this new Serious Game based assessment tool is a user-friendly and ecological method to evaluate the cognitive abilities related to the difficulties patients can encounter in daily living activities and can be used as a screening tool as it allowed to distinguish Alzheimer's patient's performance from healthy controls.

Postural control strategies during single limb stance following acute lateral ankle sprain.

PubMed

Doherty, Cailbhe; Bleakley, Chris; Hertel, Jay; Caulfield, Brian; Ryan, John; Delahunt, Eamonn

2014-06-01

Single-limb stance is maintained via the integration of visual, vestibular and somatosensory afferents. Musculoskeletal injury challenges the somatosensory system to reweight distorted sensory afferents. This investigation supplements kinetic analysis of eyes-open and eyes-closed single-limb stance tasks with a kinematic profile of lower limb postural orientation in an acute lateral ankle sprain group to assess the adaptive capacity of the sensorimotor system to injury. Sixty-six participants with first-time acute lateral ankle sprain completed a 20-second eyes-open single-limb stance task on their injured and non-injured limbs (task 1). Twenty-three of these participants successfully completed the same 20-second single-limb stance task with their eyes closed (task 2). A non-injured control group of 19 participants completed task 1, with 16 completing task 2. 3-dimensional kinematics of the hip, knee and ankle joints, as well as associated fractal dimension of the center-of-pressure path were determined for each limb during these tasks. Between trial analyses revealed significant differences in stance limb kinematics and fractal dimension of the center-of-pressure path for task 2 only. The control group bilaterally assumed a position of greater hip flexion compared to injured participants on their side-matched "involved"(7.41 [6.1°] vs 1.44 [4.8]°; η(2)=.34) and "uninvolved" (9.59 [8.5°] vs 2.16 [5.6°]; η(2)=.31) limbs, with a greater fractal dimension of the center-of-pressure path (involved limb=1.39 [0.16°] vs 1.25 [0.14°]; uninvolved limb=1.37 [0.21°] vs 1.23 [0.14°]). Bilateral impairment in postural control strategies present following a first time acute lateral ankle sprain. Copyright © 2014 Elsevier Ltd. All rights reserved.

Quantum Image Processing and Its Application to Edge Detection: Theory and Experiment

NASA Astrophysics Data System (ADS)

Yao, Xi-Wei; Wang, Hengyan; Liao, Zeyang; Chen, Ming-Cheng; Pan, Jian; Li, Jun; Zhang, Kechao; Lin, Xingcheng; Wang, Zhehui; Luo, Zhihuang; Zheng, Wenqiang; Li, Jianzhong; Zhao, Meisheng; Peng, Xinhua; Suter, Dieter

2017-07-01

Processing of digital images is continuously gaining in volume and relevance, with concomitant demands on data storage, transmission, and processing power. Encoding the image information in quantum-mechanical systems instead of classical ones and replacing classical with quantum information processing may alleviate some of these challenges. By encoding and processing the image information in quantum-mechanical systems, we here demonstrate the framework of quantum image processing, where a pure quantum state encodes the image information: we encode the pixel values in the probability amplitudes and the pixel positions in the computational basis states. Our quantum image representation reduces the required number of qubits compared to existing implementations, and we present image processing algorithms that provide exponential speed-up over their classical counterparts. For the commonly used task of detecting the edge of an image, we propose and implement a quantum algorithm that completes the task with only one single-qubit operation, independent of the size of the image. This demonstrates the potential of quantum image processing for highly efficient image and video processing in the big data era.

Do you make a difference? Social context in a betting task

PubMed Central

Nelson, Eric E.; Pine, Daniel S.; Ernst, Monique

2008-01-01

Social context strongly influences human motivated behavior. The triadic model implicates three major nodes in the regulation of motivated behavior, i.e. amygdala, medial prefrontal cortex (mPFC) and striatum. The present work examines how social context modulates this system. Nineteen healthy subjects completed an event-related functional magnetic resonance imaging study of a monetary betting task in the presence (social trials) and in the absence of a social peer (nonsocial trials). In the social trials, the scanned subject played along with another subject, although their performances were independent from one another. In the nonsocial trials the scanned subject played alone. Although behavioral performance did not differ between social and nonsocial trials, BOLD signal changes during betting were significantly greater in the amygdala bilaterally and the right dorsolateral prefrontal cortex (BA 9) in the social condition relative to the nonsocial condition. In contrast, activation was greater in ventral striatum in the nonsocial condition relative to the social condition. These findings suggest that social context modulates the triadic neural-systems ensemble to adjust motivated behavior to the unique demands associated with the presence of conspecifics. PMID:19015081

Proposal for a lunar landing pod for SKITTER

NASA Technical Reports Server (NTRS)

Herman, David; Huang, Frank; Morelli, Mark; Njaka, Chima; Pope, Michael; Rice, Michael

1987-01-01

The purpose of this project is to design a lunar landing module for the SKITTER vehicle. SKITTER is a three-legged mobile lunar transport and work platform. This lunar landing module must be able to bring SKITTER, with attached crane, from a lunar orbit to the surface of the Moon. This propulsion system is entirely self-contained and removable after touchdown. SKITTER is unmanned and must be able to touch down on the lunar surface and perform assigned tasks independently of other space or lunar vehicles. The propulsion system is designed to ensure that the vehicle will make a lunar landing within the expected velocity range. A landing gear configuration is presented to safely dissipate landing forces on lunar impact and be removed from the SKITTER structure after touchdown. The overall engineering analysis was conducted to determine an economical design to land SKITTER safely on the Moon. SKITTER will perform various tasks on the surface of the Moon. The completion of this project will determine the feasibility of landing SKITTER with the attached crane safely on the lunar surface.

Exceptional lexical skills but executive language deficits in school starters and young adults with Turners syndrome: implications for X chromosome effects on brain function.

PubMed

Temple, Christine M; Shephard, Elizabeth E

2012-03-01

TS school starters had enhanced receptive and expressive language on standardised assessment (CELF-P) and enhanced rhyme judgements, spoonerisms, and lexical decision, indicating enhanced phonological skills and word representations. There was marginal but consistent advantage across lexico-semantic tasks. On executive tasks, speeded naming of numbers was impaired but not pictures. Young TS adults had enhanced naming and receptive vocabulary, indicating enhanced semantic skills. There were consistent deficits in executive language: phonemic oral fluency, rhyme fluency, speeded naming of pictures, numbers and colours; sentence completion requiring supression of prepotent responses. Haploinsufficiency of X-chromosome drives mechanisms that affect the anatomical and neurochemical development of the brain, resulting in enhanced temporal lobe aspects of language. These strengths co-exist with impaired development of frontal lobe executive language systems. This means not only that these elements of language can decouple in development but that their very independence is driven by mechanisms linked to the X-chromosome. Copyright © 2011 Elsevier Inc. All rights reserved.

Action-Effect Associations in Voluntary and Cued Task-Switching.

PubMed

Sommer, Angelika; Lukas, Sarah

2017-01-01

The literature of action control claims that humans control their actions in two ways. In the stimulus-based approach, actions are triggered by external stimuli. In the ideomotor approach, actions are elicited endogenously and controlled by the intended goal. In the current study, our purpose was to investigate whether these two action control modes affect task-switching differently. We combined a classical task-switching paradigm with action-effect learning. Both experiments consisted of two experimental phases: an acquisition phase, in which associations between task, response and subsequent action effects were learned and a test phase, in which the effects of these associations were tested on task performance by presenting the former action effects as preceding effects, prior to the task (called practiced effects ). Subjects either chose freely between tasks (ideomotor action control mode) or they were cued as to which task to perform (sensorimotor action control mode). We aimed to replicate the consistency effect (i.e., task is chosen according to the practiced task-effect association) and non-reversal advantage (i.e., better task performance when the practiced effect matches the previously learned task-effect association). Our results suggest that participants acquired stable action-effect associations independently of the learning mode. The consistency effect (Experiment 1) could be shown, independent of the learning mode, but only on the response-level. The non-reversal advantage (Experiment 2) was only evident in the error rates and only for participants who had practiced in the ideomotor action control mode.

Action-Effect Associations in Voluntary and Cued Task-Switching

PubMed Central

Sommer, Angelika; Lukas, Sarah

2018-01-01

The literature of action control claims that humans control their actions in two ways. In the stimulus-based approach, actions are triggered by external stimuli. In the ideomotor approach, actions are elicited endogenously and controlled by the intended goal. In the current study, our purpose was to investigate whether these two action control modes affect task-switching differently. We combined a classical task-switching paradigm with action-effect learning. Both experiments consisted of two experimental phases: an acquisition phase, in which associations between task, response and subsequent action effects were learned and a test phase, in which the effects of these associations were tested on task performance by presenting the former action effects as preceding effects, prior to the task (called practiced effects). Subjects either chose freely between tasks (ideomotor action control mode) or they were cued as to which task to perform (sensorimotor action control mode). We aimed to replicate the consistency effect (i.e., task is chosen according to the practiced task-effect association) and non-reversal advantage (i.e., better task performance when the practiced effect matches the previously learned task-effect association). Our results suggest that participants acquired stable action-effect associations independently of the learning mode. The consistency effect (Experiment 1) could be shown, independent of the learning mode, but only on the response-level. The non-reversal advantage (Experiment 2) was only evident in the error rates and only for participants who had practiced in the ideomotor action control mode. PMID:29387027

Alpha power increases in right parietal cortex reflects focused internal attention

PubMed Central

Benedek, Mathias; Schickel, Rainer J.; Jauk, Emanuel; Fink, Andreas; Neubauer, Aljoscha C.

2014-01-01

This study investigated the functional significance of EEG alpha power increases, a finding that is consistently observed in various memory tasks and specifically during divergent thinking. It was previously shown that alpha power is increased when tasks are performed in mind—e.g., when bottom-up processing is prevented. This study aimed to examine the effect of task-immanent differences in bottom-up processing demands by comparing two divergent thinking tasks, one intrinsically relying on bottom-up processing (sensory-intake task) and one that is not (sensory-independence task). In both tasks, stimuli were masked in half of the trials to establish conditions of higher and lower internal processing demands. In line with the hypotheses, internal processing affected performance and led to increases in alpha power only in the sensory-intake task, whereas the sensory-independence task showed high levels of task-related alpha power in both conditions. Interestingly, conditions involving focused internal attention showed a clear lateralization with higher alpha power in parietal regions of the right hemisphere. Considering evidence from fMRI studies, right-parietal alpha power increases may correspond to a deactivation of the right temporoparietal junction, reflecting an inhibition of the ventral attention network. Inhibition of this region is thought to prevent reorienting to irrelevant stimulation during goal-driven, top-down behavior, which may serve the executive function of task shielding during demanding cognitive tasks such as idea generation and mental imagery. PMID:24561034

Selecting Tasks for Evaluating Human Performance as a Function of Gravity

NASA Technical Reports Server (NTRS)

Norcross, J. R.; Gernhardt, M. L.

2010-01-01

A challenge in understanding human performance as a function of gravity is determining which tasks to research. Initial studies began with treadmill walking, which was easy to quantify and control. However, with the development of pressurized rovers, it is less important to optimize human performance for ambulation as rovers will likely perform gross translation for them. Future crews are likely to spend much of their extravehicular activity (EVA) performing geology, construction and maintenance type tasks, for which it is difficult to measure steady-state-workloads. To evaluate human performance in reduced gravity, we have collected metabolic, biomechanical and subjective data for different tasks at varied gravity levels. Methods: Ten subjects completed 5 different tasks including weight transfer, shoveling, treadmill walking, treadmill running and treadmill incline walking. All tasks were performed shirt-sleeved at 1-g, 3/8-g and 1/6-g. Off-loaded conditions were achieved via the Active Response Gravity Offload System. Treadmill tasks were performed for 3 minutes with reported oxygen consumption (VO2) averaged over the last 2 minutes. Shoveling was performed for 3 minutes with metabolic cost reported as ml O2 consumed per kg material shoveled. Weight transfer reports metabolic cost as liters O2 consumed to complete the task. Statistical analysis was performed via repeated measures ANOVA. Results: Statistically significant metabolic differences were noted between all 3 gravity levels for treadmill running and incline walking. For the other 3 tasks, there were significant differences between 1-g and each reduced gravity, but not between 1/6-g and 3/8-g. For weight transfer, significant differences were seen between gravities in both trial-average VO2 and time-to-completion with noted differences in strategy for task completion. Conclusion: To determine if gravity has a metabolic effect on human performance, this research may indicate that tasks should be selected that require the subject to work vertically against the force of gravity.

Implementation Of Fuzzy Approach To Improve Time Estimation [Case Study Of A Thermal Power Plant Is Considered

NASA Astrophysics Data System (ADS)

Pradhan, Moumita; Pradhan, Dinesh; Bandyopadhyay, G.

2010-10-01

Fuzzy System has demonstrated their ability to solve different kinds of problem in various application domains. There is an increasing interest to apply fuzzy concept to improve tasks of any system. Here case study of a thermal power plant is considered. Existing time estimation represents time to complete tasks. Applying fuzzy linear approach it becomes clear that after each confidence level least time is taken to complete tasks. As time schedule is less than less amount of cost is needed. Objective of this paper is to show how one system becomes more efficient in applying Fuzzy Linear approach. In this paper we want to optimize the time estimation to perform all tasks in appropriate time schedules. For the case study, optimistic time (to), pessimistic time (tp), most likely time(tm) is considered as data collected from thermal power plant. These time estimates help to calculate expected time(te) which represents time to complete particular task to considering all happenings. Using project evaluation and review technique (PERT) and critical path method (CPM) concept critical path duration (CPD) of this project is calculated. This tells that the probability of fifty percent of the total tasks can be completed in fifty days. Using critical path duration and standard deviation of the critical path, total completion of project can be completed easily after applying normal distribution. Using trapezoidal rule from four time estimates (to, tm, tp, te), we can calculate defuzzyfied value of time estimates. For range of fuzzy, we consider four confidence interval level say 0.4, 0.6, 0.8,1. From our study, it is seen that time estimates at confidence level between 0.4 and 0.8 gives the better result compared to other confidence levels.

Vision function testing for a suprachoroidal retinal prosthesis: effects of image filtering

NASA Astrophysics Data System (ADS)

Barnes, Nick; Scott, Adele F.; Lieby, Paulette; Petoe, Matthew A.; McCarthy, Chris; Stacey, Ashley; Ayton, Lauren N.; Sinclair, Nicholas C.; Shivdasani, Mohit N.; Lovell, Nigel H.; McDermott, Hugh J.; Walker, Janine G.; BVA Consortium,the

2016-06-01

Objective. One strategy to improve the effectiveness of prosthetic vision devices is to process incoming images to ensure that key information can be perceived by the user. This paper presents the first comprehensive results of vision function testing for a suprachoroidal retinal prosthetic device utilizing of 20 stimulating electrodes. Further, we investigate whether using image filtering can improve results on a light localization task for implanted participants compared to minimal vision processing. No controlled implanted participant studies have yet investigated whether vision processing methods that are not task-specific can lead to improved results. Approach. Three participants with profound vision loss from retinitis pigmentosa were implanted with a suprachoroidal retinal prosthesis. All three completed multiple trials of a light localization test, and one participant completed multiple trials of acuity tests. The visual representations used were: Lanczos2 (a high quality Nyquist bandlimited downsampling filter); minimal vision processing (MVP); wide view regional averaging filtering (WV); scrambled; and, system off. Main results. Using Lanczos2, all three participants successfully completed a light localization task and obtained a significantly higher percentage of correct responses than using MVP (p≤slant 0.025) or with system off (p\\lt 0.0001). Further, in a preliminary result using Lanczos2, one participant successfully completed grating acuity and Landolt C tasks, and showed significantly better performance (p=0.004) compared to WV, scrambled and system off on the grating acuity task. Significance. Participants successfully completed vision tasks using a 20 electrode suprachoroidal retinal prosthesis. Vision processing with a Nyquist bandlimited image filter has shown an advantage for a light localization task. This result suggests that this and targeted, more advanced vision processing schemes may become important components of retinal prostheses to enhance performance. ClinicalTrials.gov Identifier: NCT01603576.

Task rotation in an underground coal mine: A pilot study.

PubMed

Jones, Olivia F; James, Carole L

2018-01-01

Task rotation is used to decrease the risk of workplace injuries and improve work satisfaction. To investigate the feasibility, benefits and challenges of implementing a task rotation schedule within an underground coalmine in NSW, Australia. A mixed method case control pilot study with the development and implementation of a task rotation schedule for 6 months with two work crews. A questionnaire including The Nordic Musculoskeletal Questionnaire, The Need for Recovery after Work Scale, and The Australian WHOQOL- BREF Australian Edition was used to survey workers at baseline, 3 and 6 months. A focus group was completed with the intervention crew and management at the completion of the study. In total, twenty-seven participants completed the survey. Significant improvements in the psychological and environmental domains of the WHOQOL-BREF questionnaire were found in the intervention crew. Musculoskeletal pain was highest in the elbow, lower back and knee, and fatigue scores improved, across both groups. The intervention crew felt 'mentally fresher', 'didn't do the same task twice in a row', and 'had more task variety which made the shift go quickly'. Task rotation was positively regarded, with psychological benefits identified. Three rotations during a 9-hour shift were feasible and practical in this environment.

Do monkeys choose to choose?

PubMed

Perdue, Bonnie M; Evans, Theodore A; Washburn, David A; Rumbaugh, Duane M; Beran, Michael J

2014-06-01

Both empirical and anecdotal evidence supports the idea that choice is preferred by humans. Previous research has demonstrated that this preference extends to nonhuman animals, but it remains largely unknown whether animals will actively seek out or prefer opportunities to choose. Here we explored the issue of whether capuchin and rhesus monkeys choose to choose. We used a modified version of the SELECT task-a computer program in which monkeys can choose the order of completion of various psychomotor and cognitive tasks. In the present experiments, each trial began with a choice between two icons, one of which allowed the monkey to select the order of task completion, and the other of which led to the assignment of a task order by the computer. In either case, subjects still had to complete the same number of tasks and the same number of task trials. The tasks were relatively easy, and the monkeys responded correctly on most trials. Thus, global reinforcement rates were approximately equated across conditions. The only difference was whether the monkey chose the task order or it was assigned, thus isolating the act of choosing. Given sufficient experience with the task icons, all monkeys showed a significant preference for choice when the alternative was a randomly assigned order of tasks. To a lesser extent, some of the monkeys maintained a preference for choice over a preferred, but computer-assigned, task order that was yoked to their own previous choice selection. The results indicated that monkeys prefer to choose when all other aspects of the task are equated.

Plantar Loading During Cutting While Wearing a Rigid Carbon Fiber Insert.

PubMed

Queen, Robin M; Abbey, Alicia N; Verma, Ravi; Butler, Robert J; Nunley, James A

2014-02-12

Context : Stress fractures are one of the most common injuries in sports, accounting for approximately 10% of all overuse injuries. Treatment of fifth metatarsal stress fractures involves both surgical and nonsurgical interventions. Fifth metatarsal stress fractures are difficult to treat because of the risks of delayed union, nonunion, and recurrent injuries. Most of these injuries occur during agility tasks, such as those performed in soccer, basketball, and lacrosse. Objective : To examine the effect of a rigid carbon graphite footplate on plantar loading during 2 agility tasks. Design :  Crossover study. Setting : Laboratory. Patients or Other Participants : A total of 19 recreational male athletes with no history of lower extremity injury in the past 6 months and no previous metatarsal stress fractures were tested. Main Outcome Measure(s) :  Seven 45° side-cut and crossover-cut tasks were completed in a shoe with or without a full-length rigid carbon plate. Testing order between the shoe conditions and the 2 cutting tasks was randomized. Plantar-loading data were recorded using instrumented insoles. Peak pressure, maximum force, force-time integral, and contact area beneath the total foot, the medial and lateral midfoot, and the medial, middle, and lateral forefoot were analyzed. A series of paired t tests was used to examine differences between the footwear conditions (carbon graphite footplate, shod) for both cutting tasks independently (α = .05). Results : During the side-cut task, the footplate increased total foot and lateral midfoot peak pressures while decreasing contact area and lateral midfoot force-time integral. During the crossover-cut task, the footplate increased total foot and lateral midfoot peak pressure and lateral forefoot force-time integral while decreasing total and lateral forefoot contact area. Conclusions : Although a rigid carbon graphite footplate altered some aspects of the plantar- pressure profile during cutting in uninjured participants, it was ineffective in reducing plantar loading beneath the fifth metatarsal.

Plantar Loading During Cutting While Wearing a Rigid Carbon Fiber Insert

PubMed Central

Queen, Robin M.; Abbey, Alicia N.; Verma, Ravi; Butler, Robert J.; Nunley, James A.

2014-01-01

Context Stress fractures are one of the most common injuries in sports, accounting for approximately 10% of all overuse injuries. Treatment of fifth metatarsal stress fractures involves both surgical and nonsurgical interventions. Fifth metatarsal stress fractures are difficult to treat because of the risks of delayed union, nonunion, and recurrent injuries. Most of these injuries occur during agility tasks, such as those performed in soccer, basketball, and lacrosse. Objective: To examine the effect of a rigid carbon graphite footplate on plantar loading during 2 agility tasks. Design:  Crossover study. Setting: Laboratory. Patients or Other Participants: A total of 19 recreational male athletes with no history of lower extremity injury in the past 6 months and no previous metatarsal stress fractures were tested. Main Outcome Measure(s):  Seven 45° side-cut and crossover-cut tasks were completed in a shoe with or without a full-length rigid carbon plate. Testing order between the shoe conditions and the 2 cutting tasks was randomized. Plantar-loading data were recorded using instrumented insoles. Peak pressure, maximum force, force-time integral, and contact area beneath the total foot, the medial and lateral midfoot, and the medial, middle, and lateral forefoot were analyzed. A series of paired t tests was used to examine differences between the footwear conditions (carbon graphite footplate, shod) for both cutting tasks independently (α = .05). Results: During the side-cut task, the footplate increased total foot and lateral midfoot peak pressures while decreasing contact area and lateral midfoot force-time integral. During the crossover-cut task, the footplate increased total foot and lateral midfoot peak pressure and lateral forefoot force-time integral while decreasing total and lateral forefoot contact area. Conclusions: Although a rigid carbon graphite footplate altered some aspects of the plantar-pressure profile during cutting in uninjured participants, it was ineffective in reducing plantar loading beneath the fifth metatarsal. PMID:24955620

The approach to engineering tasks composition on knowledge portals

NASA Astrophysics Data System (ADS)

Novogrudska, Rina; Globa, Larysa; Schill, Alexsander; Romaniuk, Ryszard; Wójcik, Waldemar; Karnakova, Gaini; Kalizhanova, Aliya

2017-08-01

The paper presents an approach to engineering tasks composition on engineering knowledge portals. The specific features of engineering tasks are highlighted, their analysis makes the basis for partial engineering tasks integration. The formal algebraic system for engineering tasks composition is proposed, allowing to set the context-independent formal structures for engineering tasks elements' description. The method of engineering tasks composition is developed that allows to integrate partial calculation tasks into general calculation tasks on engineering portals, performed on user request demand. The real world scenario «Calculation of the strength for the power components of magnetic systems» is represented, approving the applicability and efficiency of proposed approach.

Selective representation of task-relevant objects and locations in the monkey prefrontal cortex.

PubMed

Everling, Stefan; Tinsley, Chris J; Gaffan, David; Duncan, John

2006-04-01

In the monkey prefrontal cortex (PFC), task context exerts a strong influence on neural activity. We examined different aspects of task context in a temporal search task. On each trial, the monkey (Macaca mulatta) watched a stream of pictures presented to left or right of fixation. The task was to hold fixation until seeing a particular target, and then to make an immediate saccade to it. Sometimes (unilateral task), the attended pictures appeared alone, with a cue at trial onset indicating whether they would be presented to left or right. Sometimes (bilateral task), the attended picture stream (cued side) was accompanied by an irrelevant stream on the opposite side. In two macaques, we recorded responses from a total of 161 cells in the lateral PFC. Many cells (75/161) showed visual responses. Object-selective responses were strongly shaped by task relevance - with stronger responses to targets than to nontargets, failure to discriminate one nontarget from another, and filtering out of information from an irrelevant stimulus stream. Location selectivity occurred rather independently of object selectivity, and independently in visual responses and delay periods between one stimulus and the next. On error trials, PFC activity followed the correct rules of the task, rather than the incorrect overt behaviour. Together, these results suggest a highly programmable system, with responses strongly determined by the rules and requirements of the task performed.

Multitask TSK fuzzy system modeling by mining intertask common hidden structure.

PubMed

Jiang, Yizhang; Chung, Fu-Lai; Ishibuchi, Hisao; Deng, Zhaohong; Wang, Shitong

2015-03-01

The classical fuzzy system modeling methods implicitly assume data generated from a single task, which is essentially not in accordance with many practical scenarios where data can be acquired from the perspective of multiple tasks. Although one can build an individual fuzzy system model for each task, the result indeed tells us that the individual modeling approach will get poor generalization ability due to ignoring the intertask hidden correlation. In order to circumvent this shortcoming, we consider a general framework for preserving the independent information among different tasks and mining hidden correlation information among all tasks in multitask fuzzy modeling. In this framework, a low-dimensional subspace (structure) is assumed to be shared among all tasks and hence be the hidden correlation information among all tasks. Under this framework, a multitask Takagi-Sugeno-Kang (TSK) fuzzy system model called MTCS-TSK-FS (TSK-FS for multiple tasks with common hidden structure), based on the classical L2-norm TSK fuzzy system, is proposed in this paper. The proposed model can not only take advantage of independent sample information from the original space for each task, but also effectively use the intertask common hidden structure among multiple tasks to enhance the generalization performance of the built fuzzy systems. Experiments on synthetic and real-world datasets demonstrate the applicability and distinctive performance of the proposed multitask fuzzy system model in multitask regression learning scenarios.

Update on the Global Campaign Against Terrorist Financing: Second Report of an Independent Task Force on Terrorist Financing

DTIC Science & Technology

2004-06-15

therefore should be the subject of additional due diligence . Independent Task Force on Terrorist Financing 47 • Cooperate fully with any multilateral...unusually talented group who brought enthusiasm, diligence , and strong analytical skills to this project. We are especially appreciative of the hard...State Department’s latest Patterns of Global Terrorism report, continue to give praise where praise is due but too often go to lengths to avoid

Overground vs. treadmill-based robotic gait training to improve seated balance in people with motor-complete spinal cord injury: a case report.

PubMed

Chisholm, Amanda E; Alamro, Raed A; Williams, Alison M M; Lam, Tania

2017-04-11

Robotic overground gait training devices, such as the Ekso, require users to actively participate in triggering steps through weight-shifting movements. It remains unknown how much the trunk muscles are activated during these movements, and if it is possible to transfer training effects to seated balance control. This study was conducted to compare the activity of postural control muscles of the trunk during overground (Ekso) vs. treadmill-based (Lokomat) robotic gait training, and evaluate changes in seated balance control in people with high-thoracic motor-complete spinal cord injury (SCI). Three individuals with motor-complete SCI from C7-T4, assumed to have no voluntary motor function below the chest, underwent robotic gait training. The participants were randomly assigned to Ekso-Lokomat-Ekso or Lokomat-Ekso-Lokomat for 10 sessions within each intervention phase for a total of 30 sessions. We evaluated static and dynamic balance control through analysis of center of pressure (COP) movements after each intervention phase. Surface electromyography was used to compare activity of the abdominal and erector spinae muscles during Ekso and Lokomat walking. We observed improved postural stability after training with Ekso compared to Lokomat during static balance tasks, indicated by reduced COP root mean square distance and ellipse area. In addition, Ekso training increased total distance of COP movements during a dynamic balance task. The trunk muscles showed increased activation during Ekso overground walking compared to Lokomat walking. Our findings suggest that the Ekso actively recruits trunk muscles through postural control mechanisms, which may lead to improved balance during sitting. Developing effective training strategies to reactivate the trunk muscles is important to facilitate independence during seated balance activity in people with SCI.

Effects of Experimental Anterior Knee Pain on Muscle Activation During Landing and Jumping Performed at Various Intensities.

PubMed

Park, Jihong; Denning, W Matt; Pitt, Jordan D; Francom, Devin; Hopkins, J Ty; Seeley, Matthew K

2017-01-01

Although knee pain is common, some facets of this pain are unclear. The independent effects (ie, independent from other knee injury or pathology) of knee pain on neural activation of lower-extremity muscles during landing and jumping have not been observed. To investigate the independent effects of knee pain on lower-extremity muscle (gastrocnemius, vastus medialis, medial hamstrings, gluteus medius, and gluteus maximus) activation amplitude during landing and jumping, performed at 2 different intensities. Laboratory-based, pretest, posttest, repeated-measures design, where all subjects performed both data-collection sessions. Thirteen able-bodied subjects performed 2 different land and jump tasks (forward and lateral) under 2 different conditions (control and pain), at 2 different intensities (high and low). For the pain condition, experimental knee pain was induced via a hypertonic saline injection into the right infrapatellar fat pad. Functional linear models were used to evaluate the influence of experimental knee pain on muscle-activation amplitude throughout the 2 land and jump tasks. Experimental knee pain independently altered activation for all of the observed muscles during various parts of the 2 different land and jump tasks. These activation alterations were not consistently influenced by task intensity. Experimental knee pain alters activation amplitude of various lower-extremity muscles during landing and jumping. The nature of the alteration varies between muscles, intensities, and phases of the movement (ie, landing and jumping). Generally, experimental knee pain inhibits the gastrocnemius, medial hamstring, and gluteus medius during landing while independently increasing activation of the same muscles during jumping.

Relational Processing Following Stroke

ERIC Educational Resources Information Center

Andrews, Glenda; Halford, Graeme S.; Shum, David; Maujean, Annick; Chappell, Mark; Birney, Damian

2013-01-01

The research examined relational processing following stroke. Stroke patients (14 with frontal, 30 with non-frontal lesions) and 41 matched controls completed four relational processing tasks: sentence comprehension, Latin square matrix completion, modified Dimensional Change Card Sorting, and n-back. Each task included items at two or three…

Single Trial Brain Electrical Patterns of an Auditory and Visual Perceptuomotor Task.

DTIC Science & Technology

1983-06-01

perceptual and cognitive processing was completed, a motor program common to both tasks was executed, regardless of differences in the stimuli or type...investigation and conclusions concerning these issues during the developmental program of 12 pilot recordings is reported in the following section. B. Task...number on the CRT screen (duration 375 msec) I second after completion of response as determined by the program . If the response was sufficiently accurate

Accounting for Independent Schools.

ERIC Educational Resources Information Center

Sonenstein, Burton

The diversity of independent schools in size, function, and mode of operation has resulted in a considerable variety of accounting principles and practices. This lack of uniformity has tended to make understanding, evaluation, and comparison of independent schools' financial statements a difficult and sometimes impossible task. This manual has…

Promoting linguistic complexity, greater message length and ease of engagement in email writing in people with aphasia: initial evidence from a study utilizing assistive writing software.

PubMed

Thiel, Lindsey; Sage, Karen; Conroy, Paul

2017-01-01

Improving email writing in people with aphasia could enhance their ability to communicate, promote interaction and reduce isolation. Spelling therapies have been effective in improving single-word writing. However, there has been limited evidence on how to achieve changes to everyday writing tasks such as email writing in people with aphasia. One potential area that has been largely unexplored in the literature is the potential use of assistive writing technologies, despite some initial evidence that assistive writing software use can lead to qualitative and quantitative improvements to spontaneous writing. This within-participants case series design study aimed to investigate the effects of using assistive writing software to improve email writing in participants with dysgraphia related to aphasia. Eight participants worked through a hierarchy of writing tasks of increasing complexity within broad topic areas that incorporate the spheres of writing need of the participants: writing for domestic needs, writing for social needs and writing for business/administrative needs. Through completing these tasks, participants had the opportunity to use the various functions of the software, such as predictive writing, word banks and text to speech. Therapy also included training and practice in basic computer and email skills to encourage increased independence. Outcome measures included email skills, keyboard skills, email writing and written picture description tasks, and a perception of disability assessment. Four of the eight participants showed statistically significant improvements to spelling accuracy within emails when using the software. At a group level there was a significant increase in word length with the software; while four participants showed noteworthy changes to the range of word classes used. Enhanced independence in email use and improvements in participants' perceptions of their writing skills were also noted. This study provided some initial evidence that assistive writing technologies can support people with aphasia in email writing across a range of important performance parameters. However, more research is needed to measure the effects of these technologies on the writing of people with aphasia, and to determine the optimal compensatory mechanisms for specific people given the linguistic-strategic resources they bring to the task of email writing. © 2016 Royal College of Speech and Language Therapists.

Assessing Abuse Risk beyond Self-Report: Analog Task of Acceptability of Parent-Child Aggression

ERIC Educational Resources Information Center

Rodriguez, Christina M.; Russa, Mary Bower; Harmon, Nancy

2011-01-01

Objectives: The present investigation reports on the development and initial validation of a new analog task, the Parent-Child Aggression Acceptability Movie Task (P-CAAM), intended to assess respondents' acceptance of parent-child aggression, including both physical discipline and physical abuse. Methods: Two independent samples were utilized to…

Task-Related Interactions between Kindergarten Children and Their Teachers: The Role of Emotional Security

ERIC Educational Resources Information Center

Thijs, Jochem T.; Koomen, Helma M. Y.

2008-01-01

This study examined the emotional security of kindergarten children in dyadic task-related interactions with their teachers. In particular, it examined the interrelations between security, task behaviours (persistence and independence), social inhibition, and teachers' support. Participants were 79 kindergartners (mean age = 69.7 months) and their…

Cognitive Style as a Factor Affecting Task-Based Reading Comprehension Test Scores

ERIC Educational Resources Information Center

Salmani-Nodoushan, Mohammad Ali

2005-01-01

For purposes of the present study, it was hypothesized that field (in)dependence would introduce systematic variance into Iranian EFL learners' overall and task-specific performance on task-based reading comprehension tests. 1743 freshman, sophomore, junior, and senior students all majoring in English at different Iranian universities and colleges…

Working memory plasticity and aging.

PubMed

Rhodes, Rebecca E; Katz, Benjamin

2017-02-01

The present research explores how the trajectory of learning on a working memory task changes throughout the life span, and whether gains in working memory performance are exclusively a question of initial working memory capacity (WMC) or whether age exerts an independent effect. In a large, cross-sectional study of younger, middle-aged, and older adults, we examined learning on a widely used working memory task-the dual n-back task-over 20 sessions of practice. We found that, while all age groups improved on the task, older adults demonstrated less improvement on the task, and also reached a lower asymptotic maximum performance than younger adults. After controlling for initial WMC, we found that age exerted independent effects on training gains and asymptotic performance; older adults tended to improve less and reached lower levels of performance than younger adults. The difference between younger and older adults' rates of learning depended in part on initial WMC. These results suggest that age-related effects on working memory include not only effects on capacity, but also plasticity and the ability to improve on a task. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Verbal makes it positive, spatial makes it negative: working memory biases judgments, attention, and moods.

PubMed

Storbeck, Justin; Watson, Philip

2014-12-01

Prior research has suggested that emotion and working memory domains are integrated, such that positive affect enhances verbal working memory, whereas negative affect enhances spatial working memory (Gray, 2004; Storbeck, 2012). Simon (1967) postulated that one feature of emotion and cognition integration would be reciprocal connectedness (i.e., emotion influences cognition and cognition influences emotion). We explored whether affective judgments and attention to affective qualities are biased by the activation of verbal and spatial working memory mind-sets. For all experiments, participants completed a 2-back verbal or spatial working memory task followed by an endorsement task (Experiments 1 & 2), word-pair selection task (Exp. 3), or attentional dot-probe task (Exp. 4). Participants who had an activated verbal, compared with spatial, working memory mind-set were more likely to endorse pictures (Exp. 1) and words (Exp. 2) as being more positive and to select the more positive word pair out of a set of word pairs that went 'together best' (Exp. 3). Additionally, people who completed the verbal working memory task took longer to disengage from positive stimuli, whereas those who completed the spatial working memory task took longer to disengage from negative stimuli (Exp. 4). Interestingly, across the 4 experiments, we observed higher levels of self-reported negative affect for people who completed the spatial working memory task, which was consistent with their endorsement and attentional bias toward negative stimuli. Therefore, emotion and working memory may have a reciprocal connectedness allowing for bidirectional influence.

Influence of input device, work surface angle, and task on spine kinematics.

PubMed

Riddell, Maureen F; Gallagher, Kaitlin M; McKinnon, Colin D; Callaghan, Jack P

2016-01-01

With the increase of tablet usage in both office and industrial workplaces, it is critical to investigate the influence of tablet usage on spine posture and movement. To quantify spine kinematics while participants interacted with a tablet or desktop computer. Fourteen participants volunteered for this study. Marker clusters were fixed onto body regions to analyze cervical and lumbar spine posture and sampled at 32 Hz (Optotrak Certus, NDI, Waterloo, Canada). Participants sat for one hour in total. Cervical and lumbar median angles and range of motion (10th to 90th % ile angles) were extracted from amplitude probability distribution functions performed on the angle data. Using a sloped desk surface at 15°, compared to a flat desk, influenced cervical flexion (p = 0.0228). Completing the form fill task resulted in the highest degree of cervical flexion (p = 0.0008) compared to the other tasks completed with cervical angles between 6.1°-8.5° higher than emailing and reading respectively. An interaction between device and task (p = 0.0061) was found for relative lumbar median spine angles. Increased lumbar flexion was recorded when using a computer versus a tablet to complete various tasks. Task influenced both cervical and lumbar spine posture with the highest cervical flexion occurring while completing a simulated data entry task. A work surface slope of 15° decreased cervical spine flexion compared to a horizontal work surface slope.

An analysis of observer-rated functional vision in patients implanted with the Argus II Retinal Prosthesis System at three years.

PubMed

Geruschat, Duane R; Richards, Thomas P; Arditi, Aries; da Cruz, Lyndon; Dagnelie, Gislin; Dorn, Jessy D; Duncan, Jacque L; Ho, Allen C; Olmos de Koo, Lisa C; Sahel, José-Alain; Stanga, Paulo E; Thumann, Gabriele; Wang, Vizhong; Greenberg, Robert J

2016-05-01

The purpose of this analysis was to compare observer-rated tasks in patients implanted with the Argus II Retinal Prosthesis System, when the device is ON versus OFF. The Functional Low-Vision Observer Rated Assessment (FLORA) instrument was administered to 26 blind patients implanted with the Argus II Retinal Prosthesis System at a mean follow-up of 36 months. FLORA is a multi-component instrument that consists in part of observer-rated assessment of 35 tasks completed with the device ON versus OFF. The ease with which a patient completes a task is scored using a four-point scale, ranging from easy (score of 1) to impossible (score of 4). The tasks are evaluated individually and organised into four discrete domains, including 'Visual orientation', 'Visual mobility', 'Daily life and 'Interaction with others'. Twenty-six patients completed each of the 35 tasks. Overall, 24 out of 35 tasks (69 per cent) were statistically significantly easier to achieve with the device ON versus OFF. In each of the four domains, patients' performances were significantly better (p < 0.05) with the device ON versus OFF, ranging from 19 to 38 per cent improvement. Patients with an Argus II Retinal Prosthesis implanted for 18 to 44 months (mean 36 months), demonstrated significantly improved completion of vision-related tasks with the device ON versus OFF. © 2016 The Authors Clinical and Experimental Optometry published by John Wiley & Sons Australia, Ltd on behalf of Optometry Australia.

An analysis of observer‐rated functional vision in patients implanted with the Argus II Retinal Prosthesis System at three years

PubMed Central

Richards, Thomas P; Arditi, Aries; da Cruz, Lyndon; Dagnelie, Gislin; Dorn, Jessy D; Duncan, Jacque L; Ho, Allen C; Olmos de Koo, Lisa C; Sahel, José‐Alain; Stanga, Paulo E; Thumann, Gabriele; Wang, Vizhong; Greenberg, Robert J

2016-01-01

Abstract Objective The purpose of this analysis was to compare observer‐rated tasks in patients implanted with the Argus II Retinal Prosthesis System, when the device is ON versus OFF. Methods The Functional Low‐Vision Observer Rated Assessment (FLORA) instrument was administered to 26 blind patients implanted with the Argus II Retinal Prosthesis System at a mean follow‐up of 36 months. FLORA is a multi‐component instrument that consists in part of observer‐rated assessment of 35 tasks completed with the device ON versus OFF. The ease with which a patient completes a task is scored using a four‐point scale, ranging from easy (score of 1) to impossible (score of 4). The tasks are evaluated individually and organised into four discrete domains, including ‘Visual orientation’, ‘Visual mobility’, ‘Daily life and ‘Interaction with others’. Results Twenty‐six patients completed each of the 35 tasks. Overall, 24 out of 35 tasks (69 per cent) were statistically significantly easier to achieve with the device ON versus OFF. In each of the four domains, patients’ performances were significantly better (p < 0.05) with the device ON versus OFF, ranging from 19 to 38 per cent improvement. Conclusion Patients with an Argus II Retinal Prosthesis implanted for 18 to 44 months (mean 36 months), demonstrated significantly improved completion of vision‐related tasks with the device ON versus OFF. PMID:26804484

Two Independent Frontal Midline Theta Oscillations during Conflict Detection and Adaptation in a Simon-Type Manual Reaching Task.

PubMed

Töllner, Thomas; Wang, Yijun; Makeig, Scott; Müller, Hermann J; Jung, Tzyy-Ping; Gramann, Klaus

2017-03-01

One of the most firmly established factors determining the speed of human behavioral responses toward action-critical stimuli is the spatial correspondence between the stimulus and response locations. If both locations match, the time taken for response production is markedly reduced relative to when they mismatch, a phenomenon called the Simon effect. While there is a consensus that this stimulus-response (S-R) conflict is associated with brief (4-7 Hz) frontal midline theta (fmθ) complexes generated in medial frontal cortex, it remains controversial (1) whether there are multiple, simultaneously active theta generator areas in the medial frontal cortex that commonly give rise to conflict-related fmθ complexes; and if so, (2) whether they are all related to the resolution of conflicting task information. Here, we combined mental chronometry with high-density electroencephalographic measures during a Simon-type manual reaching task and used independent component analysis and time-frequency domain statistics on source-level activities to model fmθ sources. During target processing, our results revealed two independent fmθ generators simultaneously active in or near anterior cingulate cortex, only one of them reflecting the correspondence between current and previous S-R locations. However, this fmθ response is not exclusively linked to conflict but also to other, conflict-independent processes associated with response slowing. These results paint a detailed picture regarding the oscillatory correlates of conflict processing in Simon tasks, and challenge the prevalent notion that fmθ complexes induced by conflicting task information represent a unitary phenomenon related to cognitive control, which governs conflict processing across various types of response-override tasks. SIGNIFICANCE STATEMENT Humans constantly monitor their environment for and adjust their cognitive control settings in response to conflicts, an ability that arguably paves the way for survival in ever-changing situations. Anterior cingulate-generated frontal midline theta (fmθ) complexes have been hypothesized to play a role in this conflict-monitoring function. However, it remains a point of contention whether fmθ complexes govern conflict processing in a unitary, paradigm-nonspecific manner. Here, we identified two independent fmθ oscillations triggered during a Simon-type task, only one of them reflecting current and previous conflicts. Importantly, this signal differed in various respects (cortical origin, intertrial history) from fmθ phenomena in other response-override tasks, challenging the prevalent notion of conflict-induced fmθ as a unitary phenomenon associated with the resolution of conflict. Copyright © 2017 the authors 0270-6474/17/372505-12$15.00/0.

The impact of cognitive control on children's goal monitoring in a time-based prospective memory task.

PubMed

Mahy, Caitlin E V; Voigt, Babett; Ballhausen, Nicola; Schnitzspahn, Katharina; Ellis, Judi; Kliegel, Matthias

2015-01-01

The present study investigated whether developmental changes in cognitive control may underlie improvements of time-based prospective memory. Five-, 7-, 9-, and 11-year-olds (N = 166) completed a driving simulation task (ongoing task) in which they had to refuel their vehicle at specific points in time (PM task). The availability of cognitive control resources was experimentally manipulated by imposing a secondary task that required divided attention. Children completed the driving simulation task both in a full-attention condition and a divided-attention condition where they had to carry out a secondary task. Results revealed that older children performed better than younger children on the ongoing task and PM task. Children performed worse on the ongoing and PM tasks in the divided-attention condition compared to the full-attention condition. With respect to time monitoring in the final interval prior to the PM target, divided attention interacted with age such that older children's time monitoring was more negatively affected by the secondary task compared to younger children. Results are discussed in terms of developmental shifts from reactive to proactive monitoring strategies.

Why are bilinguals better than monolinguals at false-belief tasks?

PubMed

Rubio-Fernández, Paula

2017-06-01

In standard Theory of Mind tasks, such as the Sally-Anne, children have to predict the behaviour of a mistaken character, which requires attributing the character a false belief. Hundreds of developmental studies in the last 30 years have shown that children under 4 fail standard false-belief tasks. However, recent studies have revealed that bilingual children and adults outperform their monolingual peers in this type of tasks. Bilinguals' better performance in false-belief tasks has generally been interpreted as a result of their better inhibitory control; that is, bilinguals are allegedly better than monolinguals at inhibiting the erroneous response to the false-belief question. In this review, I challenge the received view and argue instead that bilinguals' better false-belief performance results from more effective attention management. This challenge ties in with two independent lines of research: on the one hand, recent studies on the role of attentional processes in false-belief tasks with monolingual children and adults; and on the other, current research on bilinguals' performance in different Executive Function tasks. The review closes with an exploratory discussion of further benefits of bilingual cognition to Theory of Mind development and pragmatics, which may be independent from Executive Function.

Fair loss-tolerant quantum coin flipping

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berlin, Guido; Brassard, Gilles; Bussieres, Felix

Coin flipping is a cryptographic primitive in which two spatially separated players, who do not trust each other, wish to establish a common random bit. If we limit ourselves to classical communication, this task requires either assumptions on the computational power of the players or it requires them to send messages to each other with sufficient simultaneity to force their complete independence. Without such assumptions, all classical protocols are so that one dishonest player has complete control over the outcome. If we use quantum communication, on the other hand, protocols have been introduced that limit the maximal bias that dishonestmore » players can produce. However, those protocols would be very difficult to implement in practice because they are susceptible to realistic losses on the quantum channel between the players or in their quantum memory and measurement apparatus. In this paper, we introduce a quantum protocol and we prove that it is completely impervious to loss. The protocol is fair in the sense that either player has the same probability of success in cheating attempts at biasing the outcome of the coin flip. We also give explicit and optimal cheating strategies for both players.« less

Backwards Fading to Speed Task Learning

DTIC Science & Technology

2013-09-01

estimates.) Table 1 Finalized Task List Task Domain Task Name Knot Tying Hand Cuff Rappel First Aid Fracture Bleed Map Reading* Resection...materials used. Hand Cuff . There are 10 steps in this task. To complete this task, the learner must manipulate a short length of rope (e.g...Design for Experiment 1 – Step Fade Experiment 1 (Step Fade) Task Type: Knot Tying Task Type: First Aid Task Complexity: Low (1) Hand Cuff (10

Dual-task testing to predict falls in community-dwelling older adults: a systematic review.

PubMed

Muir-Hunter, S W; Wittwer, J E

2016-03-01

Cognitive impairment increases fall risk in older adults. Dual-task testing is an accepted way to assess the interaction between cognition and mobility; however, there is a lack of evidence-based recommendations for dual-task testing to evaluate fall risk in clinical practice. To evaluate the association between dual-task testing protocols and future fall risk, and to identify the specific dual-task test protocols associated with elevated risk. MEDLINE, Pubmed and EMBASE electronic databases were searched from January 1988 to September 2013. Two independent raters identified prospective cohort studies (duration of at least 1 year) of dual-task assessment in community-dwelling participants aged ≥60 years, with 'falls' as the primary outcome. Methodological quality was scored independently by two raters using a published checklist of criteria for evaluating threats to the validity of observational studies. Deterioration in gait during dual-task testing compared with single-task performance was associated with increased fall risk. Shortcomings within the literature significantly limit knowledge translation of dual-task gait protocols into clinical practice. There is a paucity of prospective studies on the association of dual-task gait assessment with fall risk. Changes in gait under dual-task testing are associated with future fall risk, and this association is stronger than that for single-task conditions. Limitations in the available literature preclude development of detailed recommendations for dual-task gait testing procedures in clinical practice to identify and stratify fall risk in older adults. Copyright © 2015 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Nonstrategic Contributions to Putatively Strategic Effects in Selective Attention Tasks

ERIC Educational Resources Information Center

Risko, Evan F.; Blais, Chris; Stolz, Jennifer A.; Besner, Derek

2008-01-01

Proportion compatible manipulations are often used to index strategic processes in selective attention tasks. Here, a subtle confound in proportion compatible manipulations is considered. Specifically, as the proportion of compatible trials increases, the ratio of complete repetitions and complete alternations to partial repetitions increases on…

Anomalous neural circuit function in schizophrenia during a virtual Morris water task.

PubMed

Folley, Bradley S; Astur, Robert; Jagannathan, Kanchana; Calhoun, Vince D; Pearlson, Godfrey D

2010-02-15

Previous studies have reported learning and navigation impairments in schizophrenia patients during virtual reality allocentric learning tasks. The neural bases of these deficits have not been explored using functional MRI despite well-explored anatomic characterization of these paradigms in non-human animals. Our objective was to characterize the differential distributed neural circuits involved in virtual Morris water task performance using independent component analysis (ICA) in schizophrenia patients and controls. Additionally, we present behavioral data in order to derive relationships between brain function and performance, and we have included a general linear model-based analysis in order to exemplify the incremental and differential results afforded by ICA. Thirty-four individuals with schizophrenia and twenty-eight healthy controls underwent fMRI scanning during a block design virtual Morris water task using hidden and visible platform conditions. Independent components analysis was used to deconstruct neural contributions to hidden and visible platform conditions for patients and controls. We also examined performance variables, voxel-based morphometry and hippocampal subparcellation, and regional BOLD signal variation. Independent component analysis identified five neural circuits. Mesial temporal lobe regions, including the hippocampus, were consistently task-related across conditions and groups. Frontal, striatal, and parietal circuits were recruited preferentially during the visible condition for patients, while frontal and temporal lobe regions were more saliently recruited by controls during the hidden platform condition. Gray matter concentrations and BOLD signal in hippocampal subregions were associated with task performance in controls but not patients. Patients exhibited impaired performance on the hidden and visible conditions of the task, related to negative symptom severity. While controls showed coupling between neural circuits, regional neuroanatomy, and behavior, patients activated different task-related neural circuits, not associated with appropriate regional neuroanatomy. GLM analysis elucidated several comparable regions, with the exception of the hippocampus. Inefficient allocentric learning and memory in patients may be related to an inability to recruit appropriate task-dependent neural circuits. Copyright 2009 Elsevier Inc. All rights reserved.

A neural measure of behavioral engagement: task-residual low-frequency blood oxygenation level-dependent activity in the precuneus.

PubMed

Zhang, Sheng; Li, Chiang-Shan Ray

2010-01-15

Brain imaging has provided a useful tool to examine the neural processes underlying human cognition. A critical question is whether and how task engagement influences the observed regional brain activations. Here we highlighted this issue and derived a neural measure of task engagement from the task-residual low-frequency blood oxygenation level-dependent (BOLD) activity in the precuneus. Using independent component analysis, we identified brain regions in the default circuit - including the precuneus and medial prefrontal cortex (mPFC) - showing greater activation during resting as compared to task residuals in 33 individuals. Time series correlations with the posterior cingulate cortex as the seed region showed that connectivity with the precuneus was significantly stronger during resting as compared to task residuals. We hypothesized that if the task-residual BOLD activity in the precuneus reflects engagement, it should account for a certain amount of variance in task-related regional brain activation. In an additional experiment of 59 individuals performing a stop signal task, we observed that the fractional amplitude of low-frequency fluctuation (fALFF) of the precuneus but not the mPFC accounted for approximately 10% of the variance in prefrontal activation related to attentional monitoring and response inhibition. Taken together, these results suggest that task-residual fALFF in the precuneus may be a potential indicator of task engagement. This measurement may serve as a useful covariate in identifying motivation-independent neural processes that underlie the pathogenesis of a psychiatric or neurological condition.

The effects of bedtime writing on difficulty falling asleep: A polysomnographic study comparing to-do lists and completed activity lists.

PubMed

Scullin, Michael K; Krueger, Madison L; Ballard, Hannah K; Pruett, Natalya; Bliwise, Donald L

2018-01-01

Bedtime worry, including worrying about incomplete future tasks, is a significant contributor to difficulty falling asleep. Previous research showed that writing about one's worries can help individuals fall asleep. We investigated whether the temporal focus of bedtime writing-writing a to-do list versus journaling about completed activities-affected sleep onset latency. Fifty-seven healthy young adults (18-30) completed a writing assignment for 5 min prior to overnight polysomnography recording in a controlled sleep laboratory. They were randomly assigned to write about tasks that they needed to remember to complete the next few days (to-do list) or about tasks they had completed the previous few days (completed list). Participants in the to-do list condition fell asleep significantly faster than those in the completed-list condition. The more specifically participants wrote their to-do list, the faster they subsequently fell asleep, whereas the opposite trend was observed when participants wrote about completed activities. Therefore, to facilitate falling asleep, individuals may derive benefit from writing a very specific to-do list for 5 min at bedtime rather than journaling about completed activities. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Task-dependent and task-independent neurovascular responses to syntactic processing⋆

PubMed Central

Caplan, David; Chen, Evan; Waters, Gloria

2008-01-01

The neural basis for syntactic processing was studied using event-related fMRI to determine the locations of BOLD signal increases in the contrast of syntactically complex sentences with center-embedded, object-extracted relative clauses and syntactically simple sentences with right-branching, subject-extracted relative clauses in a group of 15 participants in three tasks. In a sentence verification task, participants saw a target sentence in one of these two syntactic forms, followed by a probe in a simple active form, and determined whether the probe expressed a proposition in the target. In a plausibility judgment task, participants determined whether a sentence in one of these two syntactic forms was plausible or implausible. Finally, in a non-word detection task, participants determined whether a sentence in one of these two syntactic forms contained only real words or a non-word. BOLD signal associated with the syntactic contrast increased in the left posterior inferior frontal gyrus in non-word detection and in a widespread set of areas in the other two tasks. We conclude that the BOLD activity in the left posterior inferior frontal gyrus reflects syntactic processing independent of concurrent cognitive operations and the more widespread areas of activation reflect the use of strategies and the use of the products of syntactic processing to accomplish tasks. PMID:18387556

Performance of Brazilian children on phonemic and semantic verbal fluency tasks

PubMed Central

Charchat-Fichman, Helenice; Oliveira, Rosinda Martins; da Silva, Andreza Morais

2011-01-01

The most used verbal fluency paradigms are semantic and letter fluency tasks. Studies suggest that these paradigms access semantic memory and executive function and are sensitive to frontal lobe disturbances. There are few studies in Brazilian samples on these paradigms. Objective The present study investigated performance, and the effects of age, on verbal fluency tasks in Brazilian children. The results were compared with those of other studies, and the consistency of the scoring criteria data is presented. Methods A sample of 119 children (7 to 10 years old) was submitted to the three phonemic fluency (F, A, M) tasks and three semantic fluency (animals, clothes, fruits) tasks. The results of thirty subjects were scored by two independent examiners. Results A significant positive correlation was found between the scores calculated by the two independent examiners. Significant positive correlations were found between performance on the semantic fluency task and the phonemic fluency task. The effect of age was significant for both tasks, and a significant difference was found between the 7- and 9-year-old subjects and between the 7- and 10-year-old subjects. The 8-year-old group did not differ to any of the other age groups. Conclusion The pattern of results was similar to that observed in previous Brazilian and international studies. PMID:29213727

Individual differences in control of language interference in late bilinguals are mainly related to general executive abilities

PubMed Central

2010-01-01

Background Recent research based on comparisons between bilinguals and monolinguals postulates that bilingualism enhances cognitive control functions, because the parallel activation of languages necessitates control of interference. In a novel approach we investigated two groups of bilinguals, distinguished by their susceptibility to cross-language interference, asking whether bilinguals with strong language control abilities ("non-switchers") have an advantage in executive functions (inhibition of irrelevant information, problem solving, planning efficiency, generative fluency and self-monitoring) compared to those bilinguals showing weaker language control abilities ("switchers"). Methods 29 late bilinguals (21 women) were evaluated using various cognitive control neuropsychological tests [e.g., Tower of Hanoi, Ruff Figural Fluency Task, Divided Attention, Go/noGo] tapping executive functions as well as four subtests of the Wechsler Adult Intelligence Scale. The analysis involved t-tests (two independent samples). Non-switchers (n = 16) were distinguished from switchers (n = 13) by their performance observed in a bilingual picture-naming task. Results The non-switcher group demonstrated a better performance on the Tower of Hanoi and Ruff Figural Fluency task, faster reaction time in a Go/noGo and Divided Attention task, and produced significantly fewer errors in the Tower of Hanoi, Go/noGo, and Divided Attention tasks when compared to the switchers. Non-switchers performed significantly better on two verbal subtests of the Wechsler Adult Intelligence Scale (Information and Similarity), but not on the Performance subtests (Picture Completion, Block Design). Conclusions The present results suggest that bilinguals with stronger language control have indeed a cognitive advantage in the administered tests involving executive functions, in particular inhibition, self-monitoring, problem solving, and generative fluency, and in two of the intelligence tests. What remains unclear is the direction of the relationship between executive functions and language control abilities. PMID:20180956

RELATIONSHIP OF COGNITIVE BEHAVIORAL THERAPY EFFECTS AND HOMEWORK IN AN INDICATED PREVENTION OF DEPRESSION INTERVENTION FOR NON-PROFESSIONAL CAREGIVERS (.).

PubMed

Otero, Patricia; Vázquez, Fernando L; Hermida, Elisabet; Díaz, Olga; Torres, Ángela

2015-06-01

Activities designed to be performed outside of the intervention are considered an essential aspect of the effectiveness of cognitive-behavioral therapy. However, these have received little attention in interventions aimed at individuals with subclinical depressive symptoms who do not yet meet diagnostic criteria for depression (indicated prevention). In this study, the completion of tasks given as homework and their relationship with post-treatment depressive symptoms was with relation to an indicated prevention of depression intervention. Eighty-nine female non-professional caregivers recruited from an official registry completed an intervention involving 11 homework tasks. Tasks performed were recorded and depressive symptoms were assessed with the Center for Epidemiologic Studies Depression Scale (CES-D). Among caregivers, 80.9% completed 9-11 tasks. The number of tasks performed was associated with post-treatment depressive symptoms, with 9 being optimal for clinically significant improvement. These findings highlight the relationship between homework and post-treatment depressive symptoms.