Perceived Difficulty with Physical Tasks, Lifestyle, and Physical Performance in Obese Children
D'Amico, Osvaldo; Sticco, Maura; Nugnes, Rosa; Mozzillo, Enza; Franzese, Adriana
2014-01-01
We estimated perceived difficulty with physical tasks, lifestyle, and physical performance in 382 children and adolescents (163 obese, 54 overweight, and 165 normal-weight subjects) and the relationship between perceived physical difficulties and sports participation, sedentary behaviors, or physical performance. Perceived difficulty with physical tasks and lifestyle habits was assessed by interview using a structured questionnaire, while physical performance was assessed through the six-minute walking test (6MWT). Obese children had higher perceived difficulty with several activities of daily living, were less engaged in sports, and had lower physical performance than normal-weight or overweight children; on the contrary, they did not differ with regard to time spent in sedentary behaviors. Perceived difficulty in running and hopping negatively predicted sports participation (P < 0.05 and <0.01, resp.), while perceived difficulty in almost all physical activities negatively predicted the 6MWT, independently of BMI (P < 0.01). Our results indicate that perception of task's difficulty level may reflect an actual difficulty in obese children. These findings may have practical implications for approaching physical activity in obese children. Exploring both the perception of a task's difficulty level and physical performance may be useful to design exercise programs that allow safe and successful participation. PMID:25105139
Ku, Po-Wen; Fox, Kenneth R; Gardiner, Paul A; Chen, Li-Jung
2016-04-01
Many studies have shown that low levels of exercise in later life are associated with the progression of difficulties with activities of daily living. However, few have assessed the independent effect of exercise components on difficulty in performing activities of daily living and explored whether the relationship between exercise and activities of daily living is reciprocal. This study aimed to examine, in a nationally representative sample of older Taiwanese, the independent effect of the frequency, duration, and intensity of exercise on difficulty with activities of daily living. A secondary objective was to explore the degree to which the relationship of late-life exercise with activities of daily living is bi-directional. Data from a fixed cohort (n = 1268, aged 70+) in 1999 with 8 years of follow-up were analyzed. Generalized estimating equation models with multivariate adjustment were performed. Participants engaging in higher levels of exercise had less difficulty with subsequent activities of daily living. Among the components of exercise, only duration, especially 30 min or more per session, was associated with fewer difficulties with activities of daily living. The relationship between exercise and activities of daily living was reciprocal, although the influence of activities of daily living on subsequent exercise levels was weaker. Exercise in later life may be able to minimize the difficulties in activities of daily living and help maintain the mobility and independence of older adults.
Summers, Janet; Larkin, Dawne; Dewey, Deborah
2008-04-01
In order to understand how age, culture, and problems in motor coordination impact the performance of activities of daily living, we used focus groups and in-depth interviews with Australian and Canadian parents to examine activities of daily living of younger (5-7 years of age) and older (8-9 years of age) children with and without DCD. By comparison with their typically developing age group, children with DCD had more difficulty with dressing, personal hygiene, and eating skills. Difficulties with postural control and fine-motor skills were reported to contribute to poorer performance of activities of daily living. As expected, competence in the performance of activities of daily living improved in the older children with and without DCD and there were few differences in the performance of daily living tasks between typical children in Australia and Canada. Overall, the motor difficulties of children with DCD had a significant impact on performance of a wide range of daily activities.
ERIC Educational Resources Information Center
Neuville, Emmanuelle; Croizet, Jean-Claude
2007-01-01
Can the salience of gender identity affect the math performance of 7-8 year old girls? Third-grade girls and boys were required to solve arithmetical problems of varied difficulty. Prior to the test, one half of the participants had their gender identity activated. Results showed that activation of gender identity affected girls' performance but…
Relationship between Speech Production and Perception in People Who Stutter.
Lu, Chunming; Long, Yuhang; Zheng, Lifen; Shi, Guang; Liu, Li; Ding, Guosheng; Howell, Peter
2016-01-01
Speech production difficulties are apparent in people who stutter (PWS). PWS also have difficulties in speech perception compared to controls. It is unclear whether the speech perception difficulties in PWS are independent of, or related to, their speech production difficulties. To investigate this issue, functional MRI data were collected on 13 PWS and 13 controls whilst the participants performed a speech production task and a speech perception task. PWS performed poorer than controls in the perception task and the poorer performance was associated with a functional activity difference in the left anterior insula (part of the speech motor area) compared to controls. PWS also showed a functional activity difference in this and the surrounding area [left inferior frontal cortex (IFC)/anterior insula] in the production task compared to controls. Conjunction analysis showed that the functional activity differences between PWS and controls in the left IFC/anterior insula coincided across the perception and production tasks. Furthermore, Granger Causality Analysis on the resting-state fMRI data of the participants showed that the causal connection from the left IFC/anterior insula to an area in the left primary auditory cortex (Heschl's gyrus) differed significantly between PWS and controls. The strength of this connection correlated significantly with performance in the perception task. These results suggest that speech perception difficulties in PWS are associated with anomalous functional activity in the speech motor area, and the altered functional connectivity from this area to the auditory area plays a role in the speech perception difficulties of PWS.
Monma, Takafumi; Takeda, Fumi; Noguchi, Haruko; Takahashi, Hideto; Tamiya, Nanako
2016-01-01
This study investigated the effects of leisure and social activities on the ability of middle-aged adults to maintain activities of daily living (ADL), and whether performing these activities alone or with others contributed to the ability to perform ADL. The study used nationally representative longitudinal data of 22,770 adults in Japan, aged 50–59 years, who did not have limitations in performing ADL at the beginning of the 5-year survey period. The study considered six activity categories: two leisure activities (“hobbies or cultural activities” and “exercise or sports”) and four social activities (“community events,” “support for children,” “support for elderly individuals,” and “other social activities”). Multiple logistic regression analysis was used to examine the relation between participation in these categories at baseline and difficulties in ADL at the 5-year follow-up. The association between the extent of social interaction during these activities (“by oneself,” “with others,” or “both”) and difficulties in ADL was also investigated. The analysis yielded significant negative correlations between “exercise or sports” and difficulties in ADL for both men and women, and between “hobbies or cultural activities” and difficulties in ADL for women. However, these significant relationships occurred only when activities were conducted “with others.” The present findings might help prevent deterioration in middle-aged adults’ performance of ADL in Japan. PMID:27788163
Fidalgo, Raquel; Torrance, Mark; Arias-Gundín, Olga; Martínez-Cocó, Begoña
2014-01-01
This paper analyses performance and the process used in carrying out a common hybrid task, such as, summarizing a text, from a developmental point of view and comparing the differences between students with and without reading difficulties. 548 students typically developing and 54 students with learning difficulties for reading (grades 5 to 8, ages 11 to 14) read and summarized a text using the triple task technique and then they did a comprehension questionnaire. Attention was paid to the various activities undertaken during this task, their cognitive cost, and the organization of reading and writing activities throughout the exercise, together with performance through evaluation of the summary and the reading comprehension questionnaire. There were no significant differences in performance or strategies used for the task between students of primary and secondary education. A linear reading-writing process was mostly employed by both, with greater cost and time needed by primary students. Students with reading difficulties did not show any strategies compensating for the greater difficulty and cognitive cost that the task represents for them. The effective and strategic use of summarizing as a learning tool seems to demand a specific training for students with or without reading difficulties.
Relationship between Speech Production and Perception in People Who Stutter
Lu, Chunming; Long, Yuhang; Zheng, Lifen; Shi, Guang; Liu, Li; Ding, Guosheng; Howell, Peter
2016-01-01
Speech production difficulties are apparent in people who stutter (PWS). PWS also have difficulties in speech perception compared to controls. It is unclear whether the speech perception difficulties in PWS are independent of, or related to, their speech production difficulties. To investigate this issue, functional MRI data were collected on 13 PWS and 13 controls whilst the participants performed a speech production task and a speech perception task. PWS performed poorer than controls in the perception task and the poorer performance was associated with a functional activity difference in the left anterior insula (part of the speech motor area) compared to controls. PWS also showed a functional activity difference in this and the surrounding area [left inferior frontal cortex (IFC)/anterior insula] in the production task compared to controls. Conjunction analysis showed that the functional activity differences between PWS and controls in the left IFC/anterior insula coincided across the perception and production tasks. Furthermore, Granger Causality Analysis on the resting-state fMRI data of the participants showed that the causal connection from the left IFC/anterior insula to an area in the left primary auditory cortex (Heschl’s gyrus) differed significantly between PWS and controls. The strength of this connection correlated significantly with performance in the perception task. These results suggest that speech perception difficulties in PWS are associated with anomalous functional activity in the speech motor area, and the altered functional connectivity from this area to the auditory area plays a role in the speech perception difficulties of PWS. PMID:27242487
... activities you used to enjoy, poor performance at school or work, sleeping more than usual, difficulty falling asleep or staying asleep, irritability, anger, aggression, changes in appetite or weight, difficulty concentrating, withdrawing ...
María, Helena Rubio G
2012-03-01
In recent years, evidence regarding acquisition of skills or critic behaviors for school performance has increased though there it is not conclusive in terms of the effectiveness in class participation. The purpose is to define the elements implicated in the acquisition of such skills or critical behaviors and describe them from the perspective of school activities involving participation. Descriptive, observational study with a sample of 28 preschool and primary school students during September 2008 and March 2009 at a public institution in the city of Cali, Colombia. The procedure was the identification of child performance capabilities using Battell's developmental inventory to describe afterwards the repercussions on student's participation in school activities. 61.5% of the children show motor difficulties; 56% exhibit socio and personal difficulties, while 46.2% reveal adaptive difficulties. These areas are fundamental for school participation in the different activities. These children have not developed the ability for an integrated control of their muscles. They also exhibit difficulties regarding social interactions and regarding the skills necessary in the performance of daily activities. The results found in this study suggest the need to enhance the study on the relevance to develop motor, personal-social, and adaptive skills in cooperation with developmental professionals. It is necessary to know and learn strategies in cooperation with the developmental professionals. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.
Performance monitoring in obsessive-compulsive undergraduates: Effects of task difficulty.
Riesel, Anja; Richter, Anika; Kaufmann, Christian; Kathmann, Norbert; Endrass, Tanja
2015-08-01
Both obsessive-compulsive disorder and subclinical obsessive-compulsive (OC) symptoms seem to be associated with hyperactive error-related brain activity. The current study examined performance monitoring in subjects with subclinical OC symptoms using a new task with different levels of difficulty. Nineteen subjects with high and 18 subjects with low OC characteristics performed a random dot cinematogram (RDC) task with three levels of difficulty. The high and low OC groups did not differ in error-related negativity (ERN), correct-related negativity (CRN) and performance irrespective of task difficulty. The amplitude of the ERN decreased with increasing difficulty whereas the magnitude of CRN did not vary. ERN and CRN approached in size and topography with increasing difficulty, which suggests that errors and correct responses are processed more similarly. These results add to a growing number of studies that fail to replicate hyperactive performance monitoring in individuals with OC symptoms in task with higher difficulty or requiring learning. Together with these findings our results suggest that the relationship between OC symptoms and performance monitoring may be sensitive to type of task and task characteristics and cannot be observed in a RDC that differs from typically used tasks in difficulty and the amount of response-conflict. Copyright © 2015 Elsevier Inc. All rights reserved.
Mamikonian-Zarpas, Ani; Laganá, Luciana
2016-01-01
Functional status is often defined by cumulative scores across indices of independence in performing basic and instrumental activities of daily living (ADL/IADL), but little is known about the unique relationship of each daily activity item with the fall outcome. The purpose of this retrospective study was to examine the level of relative risk for a future fall associated with difficulty with performing various tasks of normal daily functioning among older adults who had fallen at least once in the past 12 months. The sample was comprised of community-dwelling individuals 70 years and older from the 1984–1990 Longitudinal Study of Aging by Kovar, Fitti, and Chyba (1992). Risk analysis was performed on individual items quantifying 6 ADLs and 7 IADLs, as well as 10 items related to mobility limitations. Within a subsample of 1,675 older adults with a history of at least one fall within the past year, the responses of individuals who reported multiple falls were compared to the responses of participants who had a single fall and reported 1) difficulty with walking and/or balance (FRAIL group, n = 413) vs. 2) no difficulty with walking or dizziness (NDW+ND group, n = 415). The items that had the strongest relationships and highest risk ratios for the FRAIL group (which had the highest probabilities for a future fall) included difficulty with: eating (73%); managing money (70%); biting or chewing food (66%); walking a quarter of a mile (65%); using fingers to grasp (65%); and dressing without help (65%). For the NDW+ND group, the most noteworthy items included difficulty with: bathing or showering (79%); managing money (77%); shopping for personal items (75%); walking up 10 steps without rest (72%); difficulty with walking a quarter of a mile (72%); and stooping/crouching/kneeling (70%). These findings suggest that individual items quantifying specific ADLs and IADLs have substantive relationships with the fall outcome among older adults who have difficulty with walking and balance, as well as among older individuals without dizziness or difficulty with walking. Furthermore, the examination of the relationships between items that are related to more challenging activities and the fall outcome revealed that higher functioning older adults who reported difficulty with the 6 items that yielded the highest risk ratios may also be at elevated risk for a fall. PMID:27200366
Berger, Christoph; Erbe, Anna-Katharina; Ehlers, Inga; Marx, Ivo; Hauenstein, Karlheinz; Teipel, Stefan
2015-01-01
Research suggests generally impaired cognitive control functions in working memory (WM) processes in amnestic mild cognitive impairment (MCI) and incipient Alzheimer's disease (AD). Little is known how emotional salience of task-irrelevant stimuli may modulate cognitive control of WM performance and neurofunctional activation in MCI and AD individuals. We investigated the impact of emotional task-irrelevant visual stimuli on cortical activation during verbal WM. Twelve AD/MCI individuals and 12 age-matched healthy individuals performed a verbal WM (nback-) task with task-irrelevant emotionally neutral and emotionally negative background pictures during fMRI measurement. AD/MCI individuals showed decreased WM performance compared with controls; both AD/MCI and control groups reacted slower during presentation of negative pictures, regardless of WM difficulty. The AD/MCI group showed increased activation in the left hemispheric prefrontal network, higher amygdala and less cerebellar activation with increasing WM task difficulty compared to healthy controls. Correlation analysis between neurofunctional activation and WM performance revealed a negative correlation between task sensitivity and activation in the dorsal anterior cingulum for the healthy controls but not for the AD/MCI group. Our data suggest compensatory activation in prefrontal cortex and amygdala, but also dysfunctional inhibition of distracting information in the AD/MCI group during higher WM task difficulty. Additionally, attentional processes affecting the correlation between WM performance and neurofunctional activation seem to be different between incipient AD and healthy aging.
Neural efficiency as a function of task demands☆
Dunst, Beate; Benedek, Mathias; Jauk, Emanuel; Bergner, Sabine; Koschutnig, Karl; Sommer, Markus; Ischebeck, Anja; Spinath, Birgit; Arendasy, Martin; Bühner, Markus; Freudenthaler, Heribert; Neubauer, Aljoscha C.
2014-01-01
The neural efficiency hypothesis describes the phenomenon that brighter individuals show lower brain activation than less bright individuals when working on the same cognitive tasks. The present study investigated whether the brain activation–intelligence relationship still applies when more versus less intelligent individuals perform tasks with a comparable person-specific task difficulty. In an fMRI-study, 58 persons with lower (n = 28) or respectively higher (n = 30) intelligence worked on simple and difficult inductive reasoning tasks having the same person-specific task difficulty. Consequently, less bright individuals received sample-based easy and medium tasks, whereas bright subjects received sample-based medium and difficult tasks. This design also allowed a comparison of lower versus higher intelligent individuals when working on the same tasks (i.e. sample-based medium task difficulty). In line with expectations, differences in task performance and in brain activation were only found for the subset of tasks with the same sample-based task difficulty, but not when comparing tasks with the same person-specific task difficulty. These results suggest that neural efficiency reflects an (ability-dependent) adaption of brain activation to the respective task demands. PMID:24489416
ERIC Educational Resources Information Center
Krein, Sarah L.; Heisler, Michele; Piette, John D.; Butchart, Amy; Kerr, Eve A.
2007-01-01
Purpose: Many older patients with common chronic conditions also experience chronic pain. We examined how chronic pain affects patients' difficulty with recommended self-management activities and the potential intervening role of self-efficacy (the level of confidence in one's own ability to perform a specific task). Design and Methods: We…
Stroke patients communicating their healthcare needs in hospital: a study within the ICF framework.
O'Halloran, Robyn; Worrall, Linda; Hickson, Louise
2012-01-01
Previous research has identified that many patients admitted into acute hospital stroke units have communication-related impairments such as hearing, vision, speech, language and/or cognitive communicative impairment. However, no research has identified how many patients in acute hospital stroke units have difficulty actually communicating their healthcare needs. The World Health Organization's International Classification of Functioning, Disability and Health (ICF) conceptualizes difficulty communicating about healthcare needs as a type of activity limitation, within the Activity and Participation component. The ICF proposes that activity limitation can be measured in four different ways. The first aim of this research was to measure a patient's difficulty communicating his or her healthcare needs, that is, activity limitation, in two of the four ways suggested by the ICF when interacting with healthcare providers. The second aim was to investigate whether communication-related impairments in hearing, vision, speech, language and/or cognitive communicative impairment predict difficulty communicating healthcare needs, measured in these ways. A total of 65 patients consecutively admitted into two acute hospital stroke units in Melbourne, Australia, who consented to this research participated in this study. Early in their admission participants were screened for hearing, vision, speech, language and cognitive communicative impairment. Participants were also assessed for difficulty communicating about healthcare needs in two ways proposed by the ICF: 'capacity with assistance' and 'performance'. Relationships between communication-related impairment and both capacity with assistance and performance were explored through Spearman's correlations and binary logistic regression. A total of 87% of patients had one or more communication-related impairments. Half of the patients (51%) had difficulty communicating their healthcare needs when assessed in terms of capacity with assistance. Slightly more patients (55%) were observed to have difficulty communicating their healthcare needs when assessed in terms of performance. More severe vision, speech, language and cognitive communicative impairment were significantly associated with more severe difficulty communicating healthcare needs. About half of the stroke patients admitted into acute hospital stroke units had difficulty communicating their healthcare needs. Patients with more severe communication-related impairments had more severe difficulty communicating their healthcare needs. Future research is needed to understand the other factors that influence communication between people with communication disabilities and their healthcare providers in acute hospital settings. © 2012 Royal College of Speech and Language Therapists.
Students' performance in phonological awareness, rapid naming, reading, and writing.
Capellini, Simone Aparecida; Lanza, Simone Cristina
2010-01-01
phonological awareness, rapid naming, reading and writing in students with learning difficulties of a municipal public school. to characterize and compare the performance of students from public schools with and without learning difficulties in phonological awareness, rapid naming, reading and writing. participants were 60 students from the 2nd to the 4th grades of municipal public schools divided into 6 groups. Each group was composed by 10 students, being 3 groups of students without learning difficulties and 3 groups with students with learning difficulties. As testing procedure phonological awareness, rapid automatized naming, oral reading and writing under dictation assessments were used. the results highlighted the better performance of students with no learning difficulties. Students with learning difficulties presented a higher ratios considering time/speed in rapid naming tasks and, consequently, lower production in activities of phonological awareness and reading and writing, when compared to students without learning difficulties. students with learning difficulties presented deficits when considering the relationship between naming and automatization skills, and among lexical access, visual discrimination, stimulus frequency use and competition in using less time for code naming, i.e. necessary for the phoneme-grapheme conversion process required in the reading and writing alphabetic system like the Portuguese language.
Kane, Kyra J; Staples, Kerri L
2016-01-01
Children with coordination difficulties are at risk of low levels of physical activity (PA) participation. This intervention examined the effects of a multidisciplinary program that emphasized parent participation on motor skill performance and PA. Ten boys (5-7 years) completed a group program consisting of conditioning exercises and activities designed to address child-selected goals. Motor proficiency and PA participation were assessed before and after the program using the Test of Gross Motor Development (TGMD-2) and triaxial accelerometers, respectively. Rating scales captured child and parent perceptions of performance for each child's goals. TGMD-2 subtest raw scores, age equivalent and percentile scores improved, along with parent ratings of their child's performance. Six children reported skill improvements. On average, moderate to vigorous PA improved by 10 min per day although these gains were not significant. Time spent in sedentary activities was unchanged. None of the children met the Canadian PA and sedentary behaviour guidelines. The results support effectiveness of a group program to improve gross motor performance and levels of PA in children with coordination difficulties. Gains in both of these domains also have the potential to impact quality of life and reduce health risks associated with inactivity.
Performance of activities of daily living in a sample of applicants for home modification services.
Johansson, Karin; Lilja, Margareta; Petersson, Ingela; Borell, Lena
2007-01-01
Home modification services are provided to support persons with functional limitations to live independently at home. It is not well known what causes individuals to apply for home modifications, or in what kind of life situation this need appears. The aim of this study was to examine the relationship between performance of activities of daily living, housing and living situation, and the home modification applied for in a sample of home modification applicants. Further, the aim was to examine differences in performance of activities of daily living between subgroups with different social support. A total of 102 participants were included in the study. Data on performance of activities of daily living was collected through interviews in the participants' homes, using structured instruments. The participants reported high levels of independence in activities of daily living, and were using assistive devices to a large extent. However, the applicants clearly experienced difficulties in performing activities related to the applied home modification. The study indicates that the main reason for applying for Home Modification Grants was perceived difficulties in performance of activities of daily living. This stresses the importance of including other aspects besides independence when trying to understand persons' activity performance and planning for occupational therapy interventions.
Horowitz-Kraus, Tzipi; Buck, Catherine; Dorrmann, Dana
2016-10-01
Narrative comprehension is a linguistic ability that is foundational for future reading ability. The aim of the current study was to examine the neural circuitry of children with reading difficulties (RD) compared to typical readers during a narrative-comprehension task. We hypothesized that due to deficient executive functions, which support narrative comprehension abilities, children with RD would display altered activation and functional connectivity, as well as lower performance on a narrative-comprehension task. Children with RD and typical readers were scanned during a narrative-comprehension task and administered reading behavioral tests. Children with RD scored significantly lower on the narrative-comprehension task than did typical readers. Composite activation maps showed more diffused activation during narrative comprehension in the RD group. Maps comparing the two reading groups showed more activation in the frontal lobes (regions responsible for executive functions), and functional connectivity showed higher global efficiency in children with RD than in typical readers. Global efficiency was negatively correlated with phonological awareness and reading and executive function scores in the entire study group. Children with RD may suffer from narrative-comprehension difficulties due to diffused activation of language areas, as was observed during a narrative-comprehension task. Greater effort in this task may be reflected by the engagement of brain regions related to executive functions and higher functional connectivity or attributed to difficulties in phonological processing and reading and executive functions. Therefore, the accommodation given to children with RD of reading aloud may need to be revised due to the observed difficulty in this domain.
Aubin, Ginette; Béliveau, Marie-France; Klinger, Evelyne
2018-07-01
People with schizophrenia often have functional limitations that affect their daily activities due to executive function deficits. One way to assess these deficits is through the use of virtual reality programmes that reproduce real-life instrumental activities of daily living (IADLs). One such programme is the Virtual Action Planning-Supermarket (VAP-S). This exploratory study aimed to examine the ecological validity of this programme, specifically, how task performance in both virtual and natural environments compares. Case studies were used and involved five participants with schizophrenia, who were familiar with grocery shopping. They were assessed during both the VAP-S shopping task and a real-life grocery shopping task using an observational assessment tool, the Perceive, Recall, Plan and Perform (PRPP) System of Task Analysis. The results show that when difficulties were present in the virtual task, difficulties were also observed in the real-life task. For some participants, greater difficulties were observed in the virtual task. These difficulties could be explained by the presence of perceptual deficits and problems remembering the required sequenced actions in the virtual task. In conclusion, performance on the VAP-S by these five participants was generally comparable to the performance in a natural environment.
48 CFR 1433.104 - Protests to GAO.
Code of Federal Regulations, 2014 CFR
2014-10-01
... report as required by FAR 33.104(a)(3). (2) The SOL will furnish promptly GAO's written notice of the... expense or difficulty in performance. If appropriate, the report shall contain a statement regarding any... difficulties or additional expense to the Government. The contracting activity shall submit the CO's report to...
48 CFR 1433.104 - Protests to GAO.
Code of Federal Regulations, 2012 CFR
2012-10-01
... report as required by FAR 33.104(a)(3). (2) The SOL will furnish promptly GAO's written notice of the... expense or difficulty in performance. If appropriate, the report shall contain a statement regarding any... difficulties or additional expense to the Government. The contracting activity shall submit the CO's report to...
48 CFR 1433.104 - Protests to GAO.
Code of Federal Regulations, 2013 CFR
2013-10-01
... report as required by FAR 33.104(a)(3). (2) The SOL will furnish promptly GAO's written notice of the... expense or difficulty in performance. If appropriate, the report shall contain a statement regarding any... difficulties or additional expense to the Government. The contracting activity shall submit the CO's report to...
Dynamic range in BOLD modulation: lifespan aging trajectories and association with performance.
Kennedy, Kristen M; Boylan, Maria A; Rieck, Jenny R; Foster, Chris M; Rodrigue, Karen M
2017-12-01
Alteration of dynamic range of modulation to cognitive difficulty has been proposed as a salient predictor of cognitive aging. Here, we examine in 171 adults (aged 20-94 years) the effects of age on dynamic modulation of blood oxygenation-level dependent activation to difficulty in parametrically increasing working memory (WM) load (0-, 2-, 3-, and 4-back conditions). First, we examined parametric increases and decreases in activation to increasing WM load (positive modulation effect and negative modulation effect). Second, we examined the effect of age on modulation to difficulty (WM load) to identify regions that differed with age as difficulty increased (age-related positive and negative modulation effects). Weakened modulation to difficulty with age was found in both the positive modulation (middle frontal, superior/inferior parietal) and negative modulation effect (deactivated) regions (insula, cingulate, medial superior frontal, fusiform, and parahippocampal gyri, hippocampus, and lateral occipital cortex). Age-related alterations to positive modulation emerged later in the lifespan than negative modulation. Furthermore, these effects were significantly coupled in that greater upmodulation was associated with lesser downmodulation. Importantly, greater fronto-parietal upmodulation to difficulty and greater downmodulation of deactivated regions were associated with better task accuracy and upmodulation with better WM span measured outside the scanner. These findings suggest that greater dynamic range of modulation of activation to cognitive challenge is in service of current task performance, as well as generalizing to cognitive ability beyond the scanner task, lending support to its utility as a marker of successful cognitive aging. Copyright © 2017 Elsevier Inc. All rights reserved.
The Effect of Age and Task Difficulty
ERIC Educational Resources Information Center
Mallo, Jason; Nordstrom, Cynthia R.; Bartels, Lynn K.; Traxler, Anthony
2007-01-01
Electronic Performance Monitoring (EPM) is a common technique used to record employee performance. EPM may include counting computer keystrokes, monitoring employees' phone calls or internet activity, or documenting time spent on work activities. Despite EPM's prevalence, no studies have examined how this management tool affects older workers--a…
Neurophysiologic monitoring of mental workload and fatigue during operation of a flight simulator
NASA Astrophysics Data System (ADS)
Smith, Michael E.; Gevins, Alan
2005-05-01
In one experiment, EEG recordings were made during a daytime session while 16 well-rested participants performed versions of a PC flight simulator task that were either low, moderate, or high in difficulty. In another experiment, the same subjects repeatedly performed high difficulty versions of the same task during an all night session with total sleep deprivation. Multivariate EEG metrics of cortical activation were derived for frontal brain regions essential for working memory and executive control processes that are presumably important for maintaining situational awareness, central brain regions essential for sensorimotor control, and posterior parietal and occipital regions essential for visuoperceptual processing. During the daytime session each of these regional measures displayed greater activation during the high difficulty task than during the low difficulty task, and degree of cortical activation was positively correlated with subjective workload ratings in these well-rested subjects. During the overnight session, cortical activation declined with time-on-task, and the degree of this decline over frontal regions was negatively correlated with subjective workload ratings. Since participants were already highly skilled in the task, such changes likely reflect fatigue-related diminishment of frontal executive capability rather than practice effects. These findings suggest that the success of efforts to gauge mental workload via proxy cortical activation measures in the context of adaptive automation systems will likely depend on use of user models that take both task demands and the operator"s state of alertness into account. Further methodological development of the measurement approach outlined here would be required to achieve a practical, effective objective means for monitoring transient changes in cognitive brain function during performance of complex real-world tasks.
2014-01-01
Background Research on the neural bases of cognitive deficits in autism spectrum disorder (ASD) has shown that working memory (WM) difficulties are associated with abnormalities in the prefrontal cortex. However, cognitive load impacts these findings, and no studies have examined the relation between WM load and neural underpinnings in children with ASD. Thus, the current study determined the effects of cognitive load on WM, using a visuo-spatial WM capacity task in children with and without ASD with functional magnetic resonance imaging (fMRI). Methods We used fMRI and a 1-back colour matching task (CMT) task with four levels of difficulty to compare the cortical activation patterns associated with WM in children (7–13 years old) with high functioning autism (N = 19) and matched controls (N = 17) across cognitive load. Results Performance on CMT was comparable between groups, with the exception of one difficulty level. Using linear trend analyses, the control group showed increasing activation as a function of difficulty level in frontal and parietal lobes, particularly between the highest difficulty levels, and decreasing activation as a function of difficulty level in the posterior cingulate and medial frontal gyri. In contrast, children with ASD showed increasing activation only in posterior brain regions and decreasing activation in the posterior cingulate and medial frontal gyri, as a function of difficulty level. Significant differences were found in the precuneus, dorsolateral prefrontal cortex and medial premotor cortex, where control children showed greater positive linear relations between cortical activity and task difficulty level, particularly at the highest difficulty levels, but children with ASD did not show these trends. Conclusions Children with ASD showed differences in activation in the frontal and parietal lobes—both critical substrates for visuo-spatial WM. Our data suggest that children with ASD rely mainly on posterior brain regions associated with visual and lower level processing, whereas controls showed activity in frontal lobes related to the classic WM network. Findings will help guide future work by localizing areas of vulnerability to developmental disturbances. PMID:25057329
Vogan, Vanessa M; Morgan, Benjamin R; Lee, Wayne; Powell, Tamara L; Smith, Mary Lou; Taylor, Margot J
2014-01-01
Research on the neural bases of cognitive deficits in autism spectrum disorder (ASD) has shown that working memory (WM) difficulties are associated with abnormalities in the prefrontal cortex. However, cognitive load impacts these findings, and no studies have examined the relation between WM load and neural underpinnings in children with ASD. Thus, the current study determined the effects of cognitive load on WM, using a visuo-spatial WM capacity task in children with and without ASD with functional magnetic resonance imaging (fMRI). We used fMRI and a 1-back colour matching task (CMT) task with four levels of difficulty to compare the cortical activation patterns associated with WM in children (7-13 years old) with high functioning autism (N = 19) and matched controls (N = 17) across cognitive load. Performance on CMT was comparable between groups, with the exception of one difficulty level. Using linear trend analyses, the control group showed increasing activation as a function of difficulty level in frontal and parietal lobes, particularly between the highest difficulty levels, and decreasing activation as a function of difficulty level in the posterior cingulate and medial frontal gyri. In contrast, children with ASD showed increasing activation only in posterior brain regions and decreasing activation in the posterior cingulate and medial frontal gyri, as a function of difficulty level. Significant differences were found in the precuneus, dorsolateral prefrontal cortex and medial premotor cortex, where control children showed greater positive linear relations between cortical activity and task difficulty level, particularly at the highest difficulty levels, but children with ASD did not show these trends. Children with ASD showed differences in activation in the frontal and parietal lobes-both critical substrates for visuo-spatial WM. Our data suggest that children with ASD rely mainly on posterior brain regions associated with visual and lower level processing, whereas controls showed activity in frontal lobes related to the classic WM network. Findings will help guide future work by localizing areas of vulnerability to developmental disturbances.
Hakun, Jonathan G; Johnson, Nathan F
2017-11-01
Older adults tend to over-activate regions throughout frontoparietal cortices and exhibit a reduced range of functional modulation during WM task performance compared to younger adults. While recent evidence suggests that reduced functional modulation is associated with poorer task performance, it remains unclear whether reduced range of modulation is indicative of general WM capacity-limitations. In the current study, we examined whether the range of functional modulation observed over multiple levels of WM task difficulty (N-Back) predicts in-scanner task performance and out-of-scanner psychometric estimates of WM capacity. Within our sample (60-77years of age), age was negatively associated with frontoparietal modulation range. Individuals with greater modulation range exhibited more accurate N-Back performance. In addition, despite a lack of significant relationships between N-Back and complex span task performance, range of frontoparietal modulation during the N-Back significantly predicted domain-general estimates of WM capacity. Consistent with previous cross-sectional findings, older individuals with less modulation range exhibited greater activation at the lowest level of task difficulty but less activation at the highest levels of task difficulty. Our results are largely consistent with existing theories of neurocognitive aging (e.g. CRUNCH) but focus attention on dynamic range of functional modulation asa novel marker of WM capacity-limitations in older adults. Copyright © 2017 Elsevier Inc. All rights reserved.
Menz, Hylton B.; Dufour, Alyssa B.; Katz, Patricia; Hannan, Marian T.
2015-01-01
Background The foot plays an important role in supporting the body when undertaking weight bearing activities. Aging is associated with an increased prevalence of foot pain and a lowering of the arch of the foot, both of which may impair mobility. Objective To examine the associations of foot pain, foot posture and dynamic foot function with self-reported mobility limitations in community-dwelling older adults. Methods Foot examinations were conducted on 1,860 members of the Framingham Study in 2002–2005. Foot posture was categorized as normal, planus or cavus using static pressure measurements, and foot function was categorized as normal, pronated or supinated using dynamic pressure measurements. Participants were asked whether they had foot pain and any difficulty performing a list of nine weight bearing tasks. Multivariate logistic regression and linear regression models were used to examine the associations of foot pain, posture, function and ability to perform these activities. Results After adjusting for age, sex, height and weight, foot pain was significantly associated with difficulty performing all nine weight bearing activities. Compared to those with normal foot posture and function, participants with planus foot posture were more likely to report difficulty remaining balanced (odds ratio [OR] = 1.40, 95% confidence interval [CI] 1.06 to 1.85; p=0.018) and individuals with pronated foot function were more likely to report difficulty walking across a small room (OR = 2.07, 95% CI 1.02 to 4.22; p=0.045). Foot pain and planus foot posture were associated with an overall mobility limitation score combining performances on each measure. Conclusion Foot pain, planus foot posture and pronated foot function are associated with self-reported difficulty undertaking common weight bearing tasks. Interventions to reduce foot pain and improve foot posture and function may therefore have a role in improving mobility in older adults. PMID:26645379
Exploratory Validation of a Multidimensional Power Wheelchair Outcomes Toolkit.
Mortenson, W Ben; Demers, Louise; Rushton, Paula W; Auger, Claudine; Routhier, Francois; Miller, William C
2015-12-01
To evaluate the relation among the measures in a power wheelchair outcomes toolkit. We performed path analysis of cross-sectional data from self-report questionnaires and 1 objective measure. Six sites. A convenience sample of power wheelchair users (N=128). Most (n=69; 53.9%) participants were women. Multiple sclerosis and spinal cord injury/disease were the most common diagnoses. Not applicable. The power wheelchair version of the Wheelchair Skills Test version 4.1 was used to carry out an objective evaluation of capacity to perform 32 wheelchair skills. The Late-Life Disability Index measured frequency of participation in 16 life activities. The Life-Space Assessment measured independence, extent, and frequency of mobility. The Assistive Technology Outcomes Profile for Mobility was used to assess perceived difficulty performing activity and participation using assistive technology. The Wheelchair Use Confidence Scale for powered wheelchair users captured users' self-efficacy with wheelchair use. Wheelchair confidence was independently associated with less difficulty with activity (β=.028, P=.002) and participation (β=.225, P<.001), increased life space (β=.095, P<.003), and greater wheelchair skills (β=.30, P<.001). Less perceived difficulty with activity was independently associated with increased frequency of participation (β=.55, P<.001). Life-space mobility was independently associated with increased frequency of participation (β=.167, P<.001). Less difficulty with participation was independently associated with greater life-space mobility (β=.59, P<.001) and greater frequency of participation (β=.13, P<.001). This study provides empirical support for the measures included as part of the power wheelchair outcomes toolkit. They appear to provide complementary information on a variety of constructs related to power wheelchair use. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Lee, Woogul; Kim, Sung-il
2014-01-01
We conducted behavioral and functional magnetic resonance imaging (fMRI) research to investigate the effects of two types of achievement goals—mastery goals and performance-approach goals— on challenge seeking and feedback processing. The results of the behavioral experiment indicated that mastery goals were associated with a tendency to seek challenge, both before and after experiencing difficulty during task performance, whereas performance-approach goals were related to a tendency to avoid challenge after encountering difficulty during task performance. The fMRI experiment uncovered a significant decrease in ventral striatal activity when participants received negative feedback for any task type and both forms of achievement goals. During the processing of negative feedback for the rule-finding task, performance-approach-oriented participants showed a substantial reduction in activity in the dorsolateral prefrontal cortex (DLPFC) and the frontopolar cortex, whereas mastery-oriented participants showed little change. These results suggest that performance-approach-oriented participants are less likely to either recruit control processes in response to negative feedback or focus on task-relevant information provided alongside the negative feedback. In contrast, mastery-oriented participants are more likely to modulate aversive valuations to negative feedback and focus on the constructive elements of feedback in order to attain their task goals. We conclude that performance-approach goals lead to a reluctant stance towards difficulty, while mastery goals encourage a proactive stance. PMID:25251396
Watanabe, Hironori; Kanehisa, Hiroaki; Yoshitake, Yasuhide
2017-10-01
The present study aimed to examine (1) the effect of task difficulty on unintended muscle activation (UIMA) levels in contralateral homologous muscle, (2) the difference between young and old adults in degree of UIMA with respect to task difficulty, and (3) temporal correlations between intended and contralateral unintended muscle activity at low frequency during unilateral intended force-matching tasks. Twelve young (21.8 ± 2.4 years) and twelve old (69.9 ± 5.3 years) adult men performed steady isometric abductions with the left index finger at 20-80% of maximal voluntary contraction force. Two task difficulties were set by adjusting the spacing between two bars centered about the target force used for visual feedback on a monitor. The amplitude of surface electromyogram (aEMG) for both hands was calculated and normalized with respect to the maximal value. To determine if oscillations between intended and unintended muscle activities were correlated, cross-correlation function (CCF) of rectified EMG for both hands at low frequency was calculated for samples deemed adequate. The unintended aEMG (right hand) had significant main effects in task difficulty, age, and target force (all P < 0.05) without any interactions. Distinct significant peaks in CCF (0.38 on average, P < 0.05) with small time lags were present between rectified EMGs of intended and unintended muscles in 14 of the 17 samples. The current results indicate that UIMA increases with greater task difficulty regardless of age, and temporal correlations exist between intended and contralateral unintended muscle activities at low frequency.
The use of subjective rating of exertion in Ergonomics.
Capodaglio, P
2002-01-01
In Ergonomics, the use of psychophysical methods for subjectively evaluating work tasks and determining acceptable loads has become more common. Daily activities at the work site are studied not only with physiological methods but also with perceptual estimation and production methods. The psychophysical methods are of special interest in field studies of short-term work tasks for which valid physiological measurements are difficult to obtain. The perceived exertion, difficulty and fatigue that a person experiences in a certain work situation is an important sign of a real or objective load. Measurement of the physical load with physiological parameters is not sufficient since it does not take into consideration the particular difficulty of the performance or the capacity of the individual. It is often difficult from technical and biomechanical analyses to understand the seriousness of a difficulty that a person experiences. Physiological determinations give important information, but they may be insufficient due to the technical problems in obtaining relevant but simple measurements for short-term activities or activities involving special movement patterns. Perceptual estimations using Borg's scales give important information because the severity of a task's difficulty depends on the individual doing the work. Observation is the most simple and used means to assess job demands. Other evaluations integrating observation are the followings: indirect estimation of energy expenditure based on prediction equations or direct measurement of oxygen consumption; measurements of forces, angles and biomechanical parameters; measurements of physiological and neurophysiological parameters during tasks. It is recommended that determinations of performances of occupational activities assess rating of perceived exertion and integrate these measurements of intensity levels with those of activity's type, duration and frequency. A better estimate of the degree of physical activity of individuals thus can be obtained.
Obremskey, William; Agel, Julie; Archer, Kristin; To, Philip; Tornetta, Paul
2016-03-01
To study the activity and incidence of knee pain after sustaining an isolated tibia fracture treated with an infrapatellar intramedullary nail at 1 year. Retrospective review of prospective cohort. Multicenter Academic and Community hospitals. Four hundred thirty-seven patients with an isolated tibia fracture completed a 12-month assessment on pain and self-reported activity. Infrapatellar intramedullary nail. Demographic information, comorbid conditions, injury characteristics, and surgical technique were recorded. Knee pain was defined on a 1-7 scale with 1 being "no pain" and 7 being a "very great deal of pain." Knee pain >4 was considered clinically significant. Patients reported if they were "able," "able with difficulty," or "unable" to perform the following activities: kneel, run, climb stairs, and walk prolonged. Variables were tested in multilevel multivariable regression analyses. In knee pain, 11% of patients reported a "good deal" to a "very great deal" of pain (>4), and 52% of patients reported "no" or "very little" pain at 12 months. In activity at 12 months, 26% and 29% of patients were unable to kneel or run, respectively, and 31% and 35% of patients, respectively, stated they were able with difficulty or unable to use stairs or walk. Clinically significant knee pain (>4/7) was present in 11% of patients 1 year after a tibia fracture. Of note, 31%-71% of patients had difficulty performing or were unable to perform routine daily activities of kneeling, running, and stair climbing, or walking prolonged distances. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.
Pilegaard, Marc Sampedro; la Cour, Karen; Gregersen Oestergaard, Lisa; Johnsen, Anna Thit; Lindahl-Jacobsen, Line; Højris, Inger; Brandt, Åse
2018-04-01
People with advanced cancer face difficulties with their everyday activities at home that may reduce their health-related quality of life. To address these difficulties, we developed the 'Cancer Home-Life Intervention'. To evaluate the efficacy of the 'Cancer Home Life-Intervention' compared with usual care with regard to patients' performance of, and participation in, everyday activities, and their health-related quality of life. A randomised controlled trial ( ClinicalTrials.gov NCT02356627). The 'Cancer Home-Life Intervention' is a brief, tailored, occupational therapy-based and adaptive programme for people with advanced cancer targeting the performance of their prioritised everyday activities. Home-living adults diagnosed with advanced cancer experiencing functional limitations were recruited from two Danish hospitals. They were assessed at baseline, and at 6 and 12 weeks of follow-up. The primary outcome was activities of daily living motor ability. Secondary outcomes were activities of daily living process ability, difficulty performing prioritised everyday activities, participation restrictions and health-related quality of life. A total of 242 participants were randomised either to the intervention group ( n = 121) or the control group ( n = 121). No effect was found on the primary outcome (between-group mean change: -0.04 logits (95% confidence interval: -0.23 to 0.15); p = 0.69). Nor was any effect on the secondary outcomes observed. In most cases, the 'Cancer Home-Life Intervention' was delivered through only one home visit and one follow-up telephone contact, which not was effective in maintaining or improving participants' everyday activities and health-related quality of life. Future research should pay even more attention to intervention development and feasibility testing.
Rubio-Grillo, María Helena; Salazar-Torres, Lenis Judith; Rojas-Fajardo, Aida
2014-03-01
There is a rising prevalence of attention deficit and hyperactivity disorder (ADHD) in educational institutions. Difficulties in academic development manifest as: slow information processing, difficulty in planning and working memory, difficulty staying focused, struggle selecting data or stimuli relevant to the implementation and completion of tasks. If adequate educational measures and specialized intervention are not established, the characteristics may affect instrumental learning. The aim of this study is to identify procedural motor skills that interfere with academic activities in a group of elementary school children, with signs and symptoms of ADHD. Descriptive study including children from 2nd to 4th grade of elementary school in which teachers detected signs and symptoms of ADHD by using questionnaires and observing school behavior. Procedural motor skills were identified and it was evidenced which skills interfered in the execution of academic activities. The population that showed inattention and hyperactivity behaviors manifested behavioral problems, low academic performance, and in turn, greater difficulty in postural skills and skill related with organization of space and objects, which interfered with the activities of daily living academic routine, as expected. The assessment of procedural motor skills allowed to determine specific difficulties in routine activities, and to agree on intervention strategies in the classroom. Copyright © 2014 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.
Kumar, Akash; Lin, Lisa; Bernheim, Oren; Bagiella, Emilia; Jandorf, Lina; Itzkowitz, Steven H.; Shah, Brijen J.
2016-01-01
Background/Aims Optimal bowel preparation is essential for successful screening or for surveillance colonoscopy (SC). Inadequate bowel preparation is associated with older age, the male gender, and the presence of certain comorbidities. However, the association between patients’ functional status and bowel preparation quality has not been studied. We prospectively examined the relationship between functional status, namely, the ability to perform activities of daily living (ADLs) and ambulate, and the quality of bowel preparation in elderly patients undergoing SC. Methods Before undergoing SC, 88 elderly patients were surveyed regarding their functional status, specifically regarding their ability to perform ADLs and ambulate a quarter of a mile. Gastroenterologists then determined the quality of the bowel preparation, which was classified as either adequate or inadequate. Then, the frequency of inadequate bowel preparation in patients who did or did not experience difficulty performing ADLs and ambulating was calculated. Results Difficulty ambulating (unadjusted odds ratio [OR], 4.83; p<0.001), difficulty performing ADLs (OR, 2.93; p=0.001), and history of diabetes (OR, 2.88; p=0.007) were significant univariate predictors of inadequate bowel preparation. After adjusting for the above variables, only difficulty ambulating (adjusted OR, 5.78; p=0.004) was an independent predictor of inadequate bowel preparation. Conclusions Difficulty with ambulation is a strong predictor of inadequate bowel preparation in elderly patients undergoing SC. PMID:27021501
An fMRI study of sex differences in regional activation to a verbal and a spatial task.
Gur, R C; Alsop, D; Glahn, D; Petty, R; Swanson, C L; Maldjian, J A; Turetsky, B I; Detre, J A; Gee, J; Gur, R E
2000-09-01
Sex differences in cognitive performance have been documented, women performing better on some phonological tasks and men on spatial tasks. An earlier fMRI study suggested sex differences in distributed brain activation during phonological processing, with bilateral activation seen in women while men showed primarily left-lateralized activation. This blood oxygen level-dependent fMRI study examined sex differences (14 men, 13 women) in activation for a spatial task (judgment of line orientation) compared to a verbal-reasoning task (analogies) that does not typically show sex differences. Task difficulty was manipulated. Hypothesized ROI-based analysis documented the expected left-lateralized changes for the verbal task in the inferior parietal and planum temporal regions in both men and women, but only men showed right-lateralized increase for the spatial task in these regions. Image-based analysis revealed a distributed network of cortical regions activated by the tasks, which consisted of the lateral frontal, medial frontal, mid-temporal, occipitoparietal, and occipital regions. The activation was more left lateralized for the verbal and more right for the spatial tasks, but men also showed some left activation for the spatial task, which was not seen in women. Increased task difficulty produced more distributed activation for the verbal and more circumscribed activation for the spatial task. The results suggest that failure to activate the appropriate hemisphere in regions directly involved in task performance may explain certain sex differences in performance. They also extend, for a spatial task, the principle that bilateral activation in a distributed cognitive system underlies sex differences in performance. Copyright 2000 Academic Press.
Handwriting difficulties in juvenile idiopathic arthritis: a pilot study.
Haberfehlner, Helga; Visser, Bart; Daffertshofer, Andreas; van Rossum, Marion Aj; Roorda, Leo D; van der Leeden, Marike; Dekker, Joost; Hoeksma, Agnes F
2011-01-01
The aim of the present study was to describe handwriting difficulties of primary school children with juvenile idiopathic arthritis (JIA), and to investigate possible correlations with hand function and writing performance. In a cross-sectional approach, 15 children with JIA and reported handwriting difficulties were included together with 15 healthy matched controls. Impairments (signs of arthritis or tenosynovitis, reduced grip force and limited range of motion of the wrist (wrist-ROM)), activity limitations (reduced quality and speed of handwriting, pain during handwriting), and participation restrictions (perceived handwriting difficulties at school) were assessed and analysed. Although selected by the presence of handwriting difficulties, the majority of the JIA children (73%) had no active arthritis of the writing hand, and only minor hand impairments were found. Overall, the JIA children performed well during the short handwriting test, but the number of letters they wrote per minute decreased significantly during the 5-minute test, compared to the healthy controls. JIA patients had significantly higher pain scores on a 100 mm Visual Analogue Scale, compared to the healthy controls. The actual presence of arthritis, and limitation in grip force and wrist-ROM did not correlate with reported participation restrictions with regard to handwriting at school. The JIA children reported pain during handwriting, and inability to sustain handwriting for a longer period of time. The results of this pilot study show that JIA children with handwriting difficulties, experience their restrictions mainly through pain and the inability to sustain handwriting for a longer period of time. No correlations could be found with impairments.
The relation between resource limitations and optional conceptual processing by children and adults.
Ackerman, B P; Spiker, K; Bailey, K
1989-10-01
In some situations children fail to perform optional conceptual processing that they are able to perform. The purpose of the 4 experiments was to determine if the difficulty of word identification affects optional conceptual processing by second/third graders, fifth graders, and college students in a cued recall task. Conceptual processing was manipulated by presenting Hard (e.g., hawk eagle canary) or Easy (river lake canary) word triplets that varied in the contrastive processing necessary to identify the "odd" target word (canary). The orienting activity also varied: for the Oddity Choice activity, contrastive processing was obligatory because the subject had to identify the target; for the Read activity, contrastive processing was optional because the experimenter identified the target. A recall advantage for the Hard over the Easy triplets was the measure of contrastive processing. Finally, the difficulty of word identification varied in that the subjects read the stimuli or the experimenter read the stimuli, and all the words were degraded, only the nontarget words were degraded, or all the words were intact. The results established that contrastive processing facilitates recall, and that word identification difficulty may limit the extent of optional contrastive processing.
Satterthwaite, Theodore D; Ruparel, Kosha; Loughead, James; Elliott, Mark A; Gerraty, Raphael T; Calkins, Monica E; Hakonarson, Hakon; Gur, Ruben C; Gur, Raquel E; Wolf, Daniel H
2012-07-02
The ventral striatum (VS) is a critical brain region for reinforcement learning and motivation. Intrinsically motivated subjects performing challenging cognitive tasks engage reinforcement circuitry including VS even in the absence of external feedback or incentives. However, little is known about how such VS responses develop with age, relate to task performance, and are influenced by task difficulty. Here we used fMRI to examine VS activation to correct and incorrect responses during a standard n-back working memory task in a large sample (n=304) of healthy children, adolescents and young adults aged 8-22. We found that bilateral VS activates more strongly to correct than incorrect responses, and that the VS response scales with the difficulty of the working memory task. Furthermore, VS response was correlated with discrimination performance during the task, and the magnitude of VS response peaked in mid-adolescence. These findings provide evidence for scalable intrinsic reinforcement signals during standard cognitive tasks, and suggest a novel link between motivation and cognition during adolescent development. Copyright © 2012 Elsevier Inc. All rights reserved.
Vigilance problems in orbiter processing
NASA Technical Reports Server (NTRS)
Swart, William W.; Safford, Robert R.; Kennedy, David B.; Yadi, Bert A.; Barth, Timothy S.
1993-01-01
A pilot experiment was done to determine what factors influence potential performance errors related to vigilance in Orbiter processing activities. The selected activities include post flight inspection for burned gap filler material and pre-rollout inspection for tile processing shim material. It was determined that the primary factors related to performance decrement were the color of the target and the difficulty of the target presentation.
Hitchcock, Caitlin; Westwell, Martin S
2017-02-01
We explored whether school-based Cogmed Working Memory Training (CWMT) may optimise both academic and psychological outcomes at school. Training of executive control skills may form a novel approach to enhancing processes that predict academic achievement, such as task-related attention, and thereby academic performance, but also has the potential to improve the regulation of emotion, social problems and behavioural difficulties. Primary school children (Mean age = 12 years, N = 148) were cluster-randomised to complete active CWMT, a nonadaptive/placebo version of CWMT, or no training. No evidence was found for training effects on task-related attention when performing academic tasks, or performance on reading comprehension and mathematics tasks, or teacher-reported social, emotional and behavioural difficulties. CWMT did not improve control of attention in the classroom, or regulation of social, emotional and behavioural difficulties. © 2016 Association for Child and Adolescent Mental Health.
Impaired regulation of emotional distractors during working memory load in schizophrenia.
Guimond, Synthia; Padani, Shezal; Lutz, Olivia; Eack, Shaun; Thermenos, Heidi; Keshavan, Matcheri
2018-06-01
Schizophrenia (SZ) patients exhibit deficits in emotion regulation that affect their daily functioning. There is evidence that the prefrontal cortex plays an important role in emotion regulation. However, it remains unclear how this brain region is involved in emotion regulation deficits in SZ, and how such deficits impact performance on cognitively demanding tasks. We examined how happy and fearful emotional distractors impact performance on working memory (WM) tasks of varying difficulty (0-back, 2-back), and brain activity using fMRI. Participants were 20 patients with SZ and 20 healthy controls (HC) matched on age, sex, race, and IQ. A significant 3-way interaction showed that SZ patients had lower performance compared to HC when exposed to fearful and happy distractors, but only during the 2-back task. Second-level fMRI between-group analysis revealed that compared to SZ patients, HC showed significantly greater increase in brain activity with WM load in the left IFG (BA 45) when exposed to fearful distractors. Less brain activity in this region was also associated with reduction in SZ patients' performance during higher WM load and the presence of fearful distractors. SZ patients had difficulty in performing a WM task when regulating emotions, and they failed to show the emotion-specific modulation of the left IFG observed in HC. These results suggest that SZ patients have difficulty with emotion regulation demands during effortful cognitive tasks. This also provides us with potential insight on how emotion regulation could be rehabilitated in SZ using cognitive training. Copyright © 2018. Published by Elsevier Ltd.
NASA Technical Reports Server (NTRS)
Smith, M. E.; Gevins, A.; Brown, H.; Karnik, A.; Du, R.
2001-01-01
Electroencephalographic (EEG) recordings were made while 16 participants performed versions of a personal-computer-based flight simulation task of low, moderate, or high difficulty. As task difficulty increased, frontal midline theta EEG activity increased and alpha band activity decreased. A participant-specific function that combined multiple EEG features to create a single load index was derived from a sample of each participant's data and then applied to new test data from that participant. Index values were computed for every 4 s of task data. Across participants, mean task load index values increased systematically with increasing task difficulty and differed significantly between the different task versions. Actual or potential applications of this research include the use of multivariate EEG-based methods to monitor task loading during naturalistic computer-based work.
The activity in the anterior insulae is modulated by perceptual decision-making difficulty.
Lamichhane, Bidhan; Adhikari, Bhim M; Dhamala, Mukesh
2016-07-07
Previous neuroimaging studies provide evidence for the involvement of the anterior insulae (INSs) in perceptual decision-making processes. However, how the insular cortex is involved in integration of degraded sensory information to create a conscious percept of environment and to drive our behaviors still remains a mystery. In this study, using functional magnetic resonance imaging (fMRI) and four different perceptual categorization tasks in visual and audio-visual domains, we measured blood oxygen level dependent (BOLD) signals and examined the roles of INSs in easy and difficult perceptual decision-making. We created a varying degree of degraded stimuli by manipulating the task-specific stimuli in these four experiments to examine the effects of task difficulty on insular cortex response. We hypothesized that significantly higher BOLD response would be associated with the ambiguity of the sensory information and decision-making difficulty. In all of our experimental tasks, we found the INS activity consistently increased with task difficulty and participants' behavioral performance changed with the ambiguity of the presented sensory information. These findings support the hypothesis that the anterior insulae are involved in sensory-guided, goal-directed behaviors and their activities can predict perceptual load and task difficulty. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.
Loidl, Verena; Oberhauser, Cornelia; Ballert, Carolina; Coenen, Michaela; Cieza, Alarcos; Sabariego, Carla
2016-04-12
Disability is understood by the World Health Organization (WHO) as the outcome of the interaction between a health condition and personal and environmental factors. Comprehensive data about environmental factors is therefore essential to understand and influence disability. We aimed to identify which environmental factors have the highest impact on the performance of people with mild, moderate and severe difficulties in capacity, who are at risk of experiencing disability to different extents, using data from a pilot study of the WHO Model Disability Survey in Cambodia and random forest regression. Hindering or facilitating aspects of places to socialize in community activities, transportation and natural environment as well as use and need of personal assistance and use of medication on a regular basis were the most important environmental factors across groups. Hindering or facilitating aspects of the general environment were the most relevant in persons experiencing mild levels of difficulties in capacity, while social support, attitudes of others and use of medication on a regular basis were highly relevant for the performance of persons experiencing moderate to higher levels of difficulties in capacity. Additionally, we corroborate the high importance of the use and need of assistive devices for people with severe difficulties in capacity.
Salvia, Emilie; Guillot, Aymeric; Collet, Christian
2012-05-01
Decision-making in daily activities require different levels of mental load depending on both objective task requirements and self-perception of task constraints. Such factors elicit strain that could influence information processing, decision-making, and forthcoming performance. This experiment aimed at studying how task difficulty, errors and unfair feedback may impact strain. Participants were requested to compare two polygons and to decide as quickly and accurately as possible whether these were identical or different. Task difficulty depended upon the number of polygon sides (from 12 to 21 sides) and their degree of similarity (different by 1, 2 or 3 sides). Reaction time (RT) and response accuracy were the dependent variables as well as electrodermal activity (EDA) and Instantaneous Heart Rate (IHR). Physiological variables from the autonomic nervous system were expected to evolve as a function of strain. As expected, we found that RT increased along with task difficulty. Similarly, the amplitude of IHR responses was affected by task difficulty. We recorded bradycardia during the 5s pre-stimulation period associated with correct responses, while wrong responses were associated with tachycardia. Bradycardia was thus a predictive index of performance related to the readiness to act when the participants focused on external cues. Processing identical polygons elicited longer electrodermal responses than those for different polygons. Indeed, the comparison of two different polygons ended as early as the difference was found. When similar, the participants were still looking for a difference and the issue was uncertain until the performance was displayed. Unfair information, i.e. wrong feedback associated with a good response, as well as response errors elicited larger and longer electrodermal responses. Autonomic nervous system activity was thus task-specific, and correlated to both cognitive and emotional processes. Copyright © 2012 Elsevier B.V. All rights reserved.
Zhang, Haoyun; Eppes, Anna; Beatty-Martínez, Anne; Navarro-Torres, Christian; Diaz, Michele T
2018-06-19
Language production and cognitive control are complex processes that involve distinct yet interacting brain networks. However, the extent to which these processes interact and their neural bases have not been thoroughly examined. Here, we investigated the neural and behavioral bases of language production and cognitive control via a phonological go/no-go picture-naming task. Naming difficulty and cognitive control demands (i.e., conflict monitoring and response inhibition) were manipulated by varying the proportion of naming trials (go trials) and inhibition trials (no-go trials) across task runs. The results demonstrated that as task demands increased, participants' behavioral performance declined (i.e., longer reaction times on naming trials, more commission errors on inhibition trials) whereas brain activation generally increased. Increased activation was found not only within the language network but also in domain-general control regions. Additionally, right superior and inferior frontal and left supramarginal gyri were sensitive to increased task difficulty during both language production and response inhibition. We also found both positive and negative brain-behavior correlations. Most notably, increased activation in sensorimotor regions, such as precentral and postcentral gyri, was associated with better behavioral performance, in both successful picture naming and successful inhibition. Moreover, comparing the strength of correlations across conditions indicated that the brain-behavior correlations in sensorimotor regions that were associated with improved performance became stronger as task demands increased. Overall, our results suggest that cognitive control demands affect language production, and that successfully coping with increases in task difficulty relies on both language-specific and domain-general cognitive control regions.
Evaluation of a novel Serious Game based assessment tool for patients with Alzheimer's disease.
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.
When to Seek Help for Your Child
... oneself Pre-Adolescents and Adolescents Marked decline in school performance Inability to cope with problems and daily activities Marked changes in sleeping and/or eating habits Extreme difficulties ...
Demb, J B; Desmond, J E; Wagner, A D; Vaidya, C J; Glover, G H; Gabrieli, J D
1995-09-01
Prefrontal cortical function was examined during semantic encoding and repetition priming using functional magnetic resonance imaging (fMRI), a noninvasive technique for localizing regional changes in blood oxygenation, a correlate of neural activity. Words studied in a semantic (deep) encoding condition were better remembered than words studied in both easier and more difficult nonsemantic (shallow) encoding conditions, with difficulty indexed by response time. The left inferior prefrontal cortex (LIPC) (Brodmann's areas 45, 46, 47) showed increased activation during semantic encoding relative to nonsemantic encoding regardless of the relative difficulty of the nonsemantic encoding task. Therefore, LIPC activation appears to be related to semantic encoding and not task difficulty. Semantic encoding decisions are performed faster the second time words are presented. This represents semantic repetition priming, a facilitation in semantic processing for previously encoded words that is not dependent on intentional recollection. The same LIPC area activated during semantic encoding showed decreased activation during repeated semantic encoding relative to initial semantic encoding of the same words. This decrease in activation during repeated encoding was process specific; it occurred when words were semantically reprocessed but not when words were nonsemantically reprocessed. The results were apparent in both individual and averaged functional maps. These findings suggest that the LIPC is part of a semantic executive system that contributes to the on-line retrieval of semantic information.
Freydefont, Laure; Gollwitzer, Peter M; Oettingen, Gabriele
2016-09-01
Two experiments investigate the influence of goal and implementation intentions on effort mobilization during task performance. Although numerous studies have demonstrated the beneficial effects of setting goals and making plans on performance, the effects of goals and plans on effort-related cardiac activity and especially the cardiac preejection period (PEP) during goal striving have not yet been addressed. According to the Motivational Intensity Theory, participants should increase effort mobilization proportionally to task difficulty as long as success is possible and justified. Forming goals and making plans should allow for reduced effort mobilization when participants perform an easy task. However, when the task is difficult, goals and plans should differ in their effect on effort mobilization. Participants who set goals should disengage, whereas participants who made if-then plans should stay in the field showing high effort mobilization during task performance. As expected, using an easy task in Experiment 1, we observed a lower cardiac PEP in both the implementation intention and the goal intention condition than in the control condition. In Experiment 2, we varied task difficulty and demonstrated that while participants with a mere goal intention disengaged from difficult tasks, participants with an implementation intention increased effort mobilization proportionally with task difficulty. These findings demonstrate the influence of goal striving strategies (i.e., mere goals vs. if-then plans) on effort mobilization during task performance. Copyright © 2016 Elsevier B.V. All rights reserved.
Karlsson, Linn; Gerdle, Björn; Takala, Esa-Pekka; Andersson, Gerhard; Larsson, Britt
2018-01-01
The purpose of this study was to describe how patients with chronic pain experience physical activity and exercise (PA&E). This qualitative interview study included 16 women and two men suffering from chronic pain and referred to a multimodal pain rehabilitation program. Semi-structured interviews were conducted and qualitative content analysis was used to analyze the interviews. One main theme emerged: "To overcome obstacles and to seize opportunities to be physically active despite chronic pain." This main theme was abstracted from five themes: "Valuing a life with physical activity," "Physical activity and exercise - before and after pain," "A struggle - difficulties and challenges," "The enabling of physical activity," and "In need of continuous and active support." Although these participants valued PA&E, they seldom achieved desirable levels, and performance of PA&E was undermined by difficulties and failure. The discrepancy between the intention to perform physical activity and the physical activity accomplished could be related to motivation, self-efficacy, and action control. The participants desired high-quality interaction with healthcare providers. The findings can be applied to chronic pain rehabilitation that uses PA&E as treatment.
Takasaki, Hiroshi; Treleaven, Julia; Johnston, Venerina; Van den Hoorn, Wolbert; Rakotonirainy, Andry; Jull, Gwendolen
2014-08-01
Individuals with chronic whiplash-associated disorders (WADs) often note driving as a difficult task. This study's aims were to (1) compare, while driving, neck motor performance, mental effort, and fatigue in individuals with chronic WAD against healthy controls and (2) investigate the relationships of these variables and neck pain to self-reported driving difficulty in the WAD group. This study involved 14 participants in each group (WAD and control). Measures included self-reported driving difficulty and measures of neck pain intensity, overall fatigue, mental effort, and neck motor performance (head rotation and upper trapezius activity) while driving a simulator. The WAD group had greater absolute path of head rotation in a simulated city area and used greater mental effort (P = 0.04), but there were no differences in other measures while driving compared with the controls (all P ≥ 0.05). Self-reported driving difficulty correlated moderately with neck pain intensity, fatigue level, and maximum velocity of head rotation while driving in the WAD group (all P < 0.05). Individuals with chronic WAD do not seem to have impaired neck motor performance while driving yet use greater mental effort. Neck pain, fatigue, and maximum head rotation velocity could be potential contributors to self-reported driving difficulty in this group.
Rapid naming, reading and comprehension in students with learning difficulties.
Silva, Cláudia da; Cunha, Vera Lúcia Orlandi; Pinheiro, Fábio Henrique; Capellini, Simone Aparecida
2012-01-01
To compare and correlate the performance of students with learning difficulties in rapid naming, reading and comprehension. Participants were 32 students from 4th grade of elementary school of both genders, with ages between 11 years and 4 months and 12 years and 7 months. The first and second oral reading of a text selected based on the indication of 4th grade teachers were conducted, as well as the first and second reading comprehension task composed by four questions presented right after the reading, to which students should answered orally, and the rapid naming task from the Test of Cognitive-Linguistic Performance, individual version. Differences were found between the first and the second comprehension scores, and between rapid naming, first and second reading. There was a strong correlation between comprehension and reading, suggesting that the performance in the first reading significantly influenced the performance in the second reading, which also occurred for comprehension. The delay in the activities of naming, reading and comprehension in the first evaluation provoked failures in the phoneme-grapheme conversion that may be enough to cause learning difficulties in reading.
Gerrard, Paul
2013-01-01
Nursing facility patients are a population that has not been well studied with regard to functional status and independence previously. As such, the manner in which activities of daily living (ADL) relate to one another is not well understood in this population. An understanding of ADL difficulty ordering has helped to devise systems of functional independence grading in other populations, which have value in understanding patients' global levels of independence and providing expectations regarding changes in function. This study seeks to examine the hierarchy of ADL in the nursing facility population. Data were analyzed from the 2004 National Nursing Home Survey, a cross-sectional data set of 13 507 skilled nursing facility subjects with functional independence items. The ADL difficulty hierarchy was determined using Rasch analysis. Item fit values for the Rasch model using Mean-Square infit statistics were also determined. The robustness of the hierarchy was tested for each ADL. Two grading systems were devised from the results of the item difficulty ordering. One was based on the most difficult item that he or she could perform, and the other assigned a grade based on the least difficult item that a subject could not perform. A total of 13 113 patients were included in this analysis, the majority of whom were female and white. They had an average age of 81 years. An ordered hierarchy of ADL was found with eating being the easiest and bathing the most difficult. All items in the Katz index fit the Rasch model adequately well. The majority of patients able to perform any particular ADL were also able to perform all easier ADL. Cohen's κ for the 2 grading systems was 0.73. This study is the first to show the expected hierarchy of difficulty of the 6 activities of daily proposed in the Katz index in the nursing facility population. The hierarchy found in this population matches the original hierarchy found in older adults in the community and acute care settings. It is also similar to hierarchy found in the inpatient rehabilitation setting. Patients would be expected to lose or gain function based on the order of difficulty, but this remains to be confirmed. Among the 6 activities of daily living tested here, their order from easiest to most difficult is eating, maintaining continence, transferring, toileting, dressing, and bathing. In addition, the index formed by these 6 items has construct validity in the nursing facility population.
la Cour, Karen; Gregersen Oestergaard, Lisa; Johnsen, Anna Thit; Lindahl-Jacobsen, Line; Højris, Inger; Brandt, Åse
2018-01-01
Background: People with advanced cancer face difficulties with their everyday activities at home that may reduce their health-related quality of life. To address these difficulties, we developed the ‘Cancer Home-Life Intervention’. Aim: To evaluate the efficacy of the ‘Cancer Home Life-Intervention’ compared with usual care with regard to patients’ performance of, and participation in, everyday activities, and their health-related quality of life. Design and intervention: A randomised controlled trial (ClinicalTrials.gov NCT02356627). The ‘Cancer Home-Life Intervention’ is a brief, tailored, occupational therapy–based and adaptive programme for people with advanced cancer targeting the performance of their prioritised everyday activities. Setting/participants: Home-living adults diagnosed with advanced cancer experiencing functional limitations were recruited from two Danish hospitals. They were assessed at baseline, and at 6 and 12 weeks of follow-up. The primary outcome was activities of daily living motor ability. Secondary outcomes were activities of daily living process ability, difficulty performing prioritised everyday activities, participation restrictions and health-related quality of life. Results: A total of 242 participants were randomised either to the intervention group (n = 121) or the control group (n = 121). No effect was found on the primary outcome (between-group mean change: −0.04 logits (95% confidence interval: −0.23 to 0.15); p = 0.69). Nor was any effect on the secondary outcomes observed. Conclusion: In most cases, the ‘Cancer Home-Life Intervention’ was delivered through only one home visit and one follow-up telephone contact, which not was effective in maintaining or improving participants’ everyday activities and health-related quality of life. Future research should pay even more attention to intervention development and feasibility testing. PMID:29299957
Benge, Jared F; Balsis, Steve
2016-01-01
Individuals with Parkinson's disease (PD) can have difficulties with activities of daily living (ADL) that stem from cognitive, motor, or affective manifestations of the disease. Accurately attributing ADL difficulty specifically to cognitive decline is critical when conducting a neuropsychological evaluation of a person with PD. Informant description of ADL performance is frequently used for this purpose, but there has been little work assessing informants' ability to attribute ADL dysfunction to a specific symptom source in PD. Fifty community dwelling individuals with PD completed cognitive, motor, and affective measures. A knowledgeable informant completed an ADL scale that asked about degree and perceived source of difficulty (cognitive, motor, affective) for each task. Informants indicated that motor dysfunction was the most common source of ADL difficulty, but the informants viewed difficulty with certain tasks, such as financial management, as particularly related to cognitive dysfunction. Informant reports of the source of ADL dysfunction (cognitive, motor, affective) were consistent with clinical measures of those specific dysfunctions. ADL dysfunction attributed to cognition specifically (χ(2) = 9.80, p = .01) was higher in those with measurable cognitive impairment. Informant reports of the sources of ADL dysfunction correlate with clinical measures of these symptoms, suggesting that informants may provide useful clinical information about the cause of ADL dysfunction in persons with PD.
Tracking Activities in Complex Settings Using Smart Environment Technologies.
Singla, Geetika; Cook, Diane J; Schmitter-Edgecombe, Maureen
2009-01-01
The pervasive sensing technologies found in smart homes offer unprecedented opportunities for providing health monitoring and assistance to individuals experiencing difficulties living independently at home. A primary challenge that needs to be tackled to meet this need is the ability to recognize and track functional activities that people perform in their own homes and everyday settings. In this paper we look at approaches to perform real-time recognition of Activities of Daily Living. We enhance other related research efforts to develop approaches that are effective when activities are interrupted and interleaved. To evaluate the accuracy of our recognition algorithms we assess them using real data collected from participants performing activities in our on-campus smart apartment testbed.
ERIC Educational Resources Information Center
Davis, Nicole; Cannistraci, Christopher J.; Rogers, Baxter P.; Gatenby, J. Christopher; Fuchs, Lynn S.; Anderson, Adam W.; Gore, John C.
2009-01-01
We used functional magnetic resonance imaging (fMRI) to explore the patterns of brain activation associated with different levels of performance in exact and approximate calculation tasks in well-defined cohorts of children with mathematical calculation difficulties (MD) and typically developing controls. Both groups of children activated the same…
Influence of mono-axis random vibration on reading activity.
Bhiwapurkar, M K; Saran, V H; Harsha, S P; Goel, V K; Berg, Mats
2010-01-01
Recent studies on train passengers' activities found that many passengers were engaged in some form of work, e.g., reading and writing, while traveling by train. A majority of the passengers reported that their activities were disturbed by vibrations or motions during traveling. A laboratory study was therefore set up to study how low-frequency random vibrations influence the difficulty to read. The study involved 18 healthy male subjects of 23 to 32 yr of age group. Random vibrations were applied in the frequency range (1-10 Hz) at 0.5, 1.0 and 1.5 m/s(2) rms amplitude along three directions (longitudinal, lateral and vertical). The effect of vibration on reading activity was investigated by giving a word chain in two different font types (Times New Roman and Arial) and three different sizes (10, 12 and 14 points) of font for each type. Subjects performed reading tasks under two sitting positions (with backrest support and leaning over a table). The judgments of perceived difficulty to read were rated using 7-point discomfort judging scale. The result shows that reading difficulty increases with increasing vibration magnitudes and found to be maximum in longitudinal direction, but with leaning over a table position. In comparison with Times New Roman type and sizes of font, subjects perceived less difficulty with Arial type for all font sizes under all vibration magnitude.
Follow-Up Activities for the HISD Kindergarten Screening Instrument.
ERIC Educational Resources Information Center
Perry, Pat; Cater, Margot
The Kindergarten Screening Instrument consists of five sub-scales and attempts to screen for possible difficulty in the areas of distant vision, hearing, eye-hand coordination, language learning, and gross motor performance. In response to many requests for follow-up activities after screening, this manual was prepared by Volunteers in Public…
A Systematic Review of Longitudinal Studies of Mathematics Difficulty.
Nelson, Gena; Powell, Sarah R
2017-06-01
Some students may be diagnosed with a learning disability in mathematics or dyscalculia, whereas other students may demonstrate below-grade-level mathematics performance without a disability diagnosis. In the literature, researchers often identify students in both groups as experiencing math difficulty. To understand the performance of students with math difficulty, we examined 35 studies that reported longitudinal results of mathematics achievement (i.e., mathematics performance measured across at least a 12-month span). Our primary goal was to conduct a systematic review of these studies and to understand whether the growth of students with math difficulty was comparable or stagnant when compared with that of students without math difficulty. We also analyzed whether identification of math difficulty was predictive of mathematics achievement in later grades and whether a diagnosis of math difficulty was stable across grade levels. Results indicate that students with math difficulty demonstrate growth on mathematics measures, but this growth still leads to lower performance than that of students without math difficulty. Identification of math difficulty is strongly related to math performance in subsequent grades, and this diagnosis is often stable. Collectively, this literature indicates that students with math difficulty continue to struggle with mathematics in later grades.
Active eye fixation performance in 940 young men: effects of IQ, schizotypy, anxiety and depression.
Smyrnis, N; Kattoulas, E; Evdokimidis, I; Stefanis, N C; Avramopoulos, D; Pantes, G; Theleritis, C; Stefanis, C N
2004-05-01
A total of 940 young men performed a task in which they actively maintained fixation for 50 s in three conditions: a). on a visual target, b). on a visual target while distracting targets appeared briefly on the periphery and c). with no visual target present. The same individuals completed psychometric evaluation tests measuring IQ, schizotypy and current state-dependent psychopathology. The proportion of fixation time decreased and saccade frequency increased in condition b compared wih condition a, and sequentially in condition c compared with condition b. A trend towards a decrease in proportion of fixation time and increase in saccade frequency was found as the subjects maintained fixation during the task and this time-dependent deterioration of performance was again most pronounced in condition c, less so in condition b and absent in condition a. Psychometric test scores were significantly correlated with fixation performance in the population. Worse performance in all three fixation conditions was observed for individuals with lower IQ scores. A deterioration of fixation performance with time in condition b was correlated with disorganization characteristics of schizotypy, suggesting that these individuals had difficulty maintaining active fixation in the presence of increased inhibitory load. A connection of such a difficulty with the frontal lobes and their role in the control of voluntary inhibitory functions is discussed.
Dissociable effects of motivation and expectancy on conflict processing: an fMRI study.
Soutschek, Alexander; Stelzel, Christine; Paschke, Lena; Walter, Henrik; Schubert, Torsten
2015-02-01
Previous studies suggest that both motivation and task difficulty expectations activate brain regions associated with cognitive control. However, it remains an open question whether motivational and cognitive determinants of control have similar or dissociable impacts on conflict processing on a neural level. The current study tested the effects of motivation and conflict expectancy on activity in regions related to processing of the target and the distractor information. Participants performed a picture-word interference task in which we manipulated the size of performance-dependent monetary rewards (level of motivation) and the ratio of congruent to incongruent trials within a block (level of conflict expectancy). Our results suggest that motivation improves conflict processing by facilitating task-relevant stimulus processing and task difficulty expectations mainly modulate the processing of distractor information. We conclude that motivation and conflict expectancy engage dissociable control strategies during conflict resolution.
The ACTIVE conceptual framework as a structural equation model.
Gross, Alden L; Payne, Brennan R; Casanova, Ramon; Davoudzadeh, Pega; Dzierzewski, Joseph M; Farias, Sarah; Giovannetti, Tania; Ip, Edward H; Marsiske, Michael; Rebok, George W; Schaie, K Warner; Thomas, Kelsey; Willis, Sherry; Jones, Richard N
2018-01-01
Background/Study Context: Conceptual frameworks are analytic models at a high level of abstraction. Their operationalization can inform randomized trial design and sample size considerations. The Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) conceptual framework was empirically tested using structural equation modeling (N=2,802). ACTIVE was guided by a conceptual framework for cognitive training in which proximal cognitive abilities (memory, inductive reasoning, speed of processing) mediate treatment-related improvement in primary outcomes (everyday problem-solving, difficulty with activities of daily living, everyday speed, driving difficulty), which in turn lead to improved secondary outcomes (health-related quality of life, health service utilization, mobility). Measurement models for each proximal, primary, and secondary outcome were developed and tested using baseline data. Each construct was then combined in one model to evaluate fit (RMSEA, CFI, normalized residuals of each indicator). To expand the conceptual model and potentially inform future trials, evidence of modification of structural model parameters was evaluated by age, years of education, sex, race, and self-rated health status. Preconceived measurement models for memory, reasoning, speed of processing, everyday problem-solving, instrumental activities of daily living (IADL) difficulty, everyday speed, driving difficulty, and health-related quality of life each fit well to the data (all RMSEA < .05; all CFI > .95). Fit of the full model was excellent (RMSEA = .038; CFI = .924). In contrast with previous findings from ACTIVE regarding who benefits from training, interaction testing revealed associations between proximal abilities and primary outcomes are stronger on average by nonwhite race, worse health, older age, and less education (p < .005). Empirical data confirm the hypothesized ACTIVE conceptual model. Findings suggest that the types of people who show intervention effects on cognitive performance potentially may be different from those with the greatest chance of transfer to real-world activities.
Oyserman, Daphna; Elmore, Kristen; Novin, Sheida; Fisher, Oliver; Smith, George C.
2018-01-01
Does experiencing difficulty bolster or undermine future self-images, strategies to get there and actual performance? We build on four insights from prior research to predict that accessible interpretation-of-experienced-difficulty mindset shapes identity and performance. First, people have two different interpretation-of-experienced-difficulty mindsets available in memory; their difficulty-as-impossibility mindset focuses attention on difficulty as implying low odds and their difficulty-as-importance mindset focuses attention on difficulty as implying high value. Second, people are sensitive to contextual cues as to which mindset to apply to understand their experienced difficulty. Third, people apply the mindset that comes to mind unless they have reason to question why it is “on-the-mind.” Fourth, social class can be thought of as a chronic context influencing how much people endorse each interpretation-of-experienced-difficulty mindset. We used subtle primes to guide participants’ attention toward either a difficulty-as-importance or a difficulty-as-impossibility mindset (N = 591). Participants guided toward a difficulty-as-importance mindset performed better on difficult academic tasks (Studies 1, 2) than participants guided toward a difficulty-as-impossibility mindset; whether they had more school-focused possible identities and linked strategies depended on sample (Studies 3, 4). For college students, the effect of guided interpretation-of-experienced-difficulty mindset was not moderated by how much participants agreed with that mindset (Studies 1, 3, 4). College students mostly disagreed with a difficulty-as-impossibility mindset, but making that mindset accessible undermined their performance and sometimes their possible identities anyway. In contrast, middle school students (a younger and lower social class sample) were more likely to agree with a difficulty-as-impossibility mindset. In this sample (Study 2), we found an effect of mindset endorsement: agreeing that difficulty implies importance and disagreeing that difficulty implies impossibility improved performance. This study had a control group. Control group participants not guided to use a particular interpretation-of-experienced-difficulty mindset performed no differently than participants guided toward a difficulty-as-impossibility mindset. Results suggest that people may chronically act as if they are using a difficulty-as-impossibility mindset and may benefit from being guided to consider that experienced difficulty might imply task importance. Effect of accessible mindset on salience of academic possible selves was not stable, accessible mindset mattered in one university sample but not the other. PMID:29887819
ERIC Educational Resources Information Center
Lintz, Larry M.; And Others
A study investigated the relationship between avionics subsystem design characteristics and training time, training cost, and job performance. A list of design variables believed to affect training and job performance was established and supplemented with personnel variables, including aptitude test scores and the amount of training and…
Cooperation driven coherence: Brains working hard together.
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.
Factors associated with fear of falling in people with Parkinson’s disease
2014-01-01
Background This study aimed to comprehensibly investigate potential contributing factors to fear of falling (FOF) among people with idiopathic Parkinson’s disease (PD). Methods The study included 104 people with PD. Mean (SD) age and PD-duration were 68 (9.4) and 5 (4.2) years, respectively, and the participants’ PD-symptoms were relatively mild. FOF (the dependent variable) was investigated with the Swedish version of the Falls Efficacy Scale, i.e. FES(S). The first multiple linear regression model replicated a previous study and independent variables targeted: walking difficulties in daily life; freezing of gait; dyskinesia; fatigue; need of help in daily activities; age; PD-duration; history of falls/near falls and pain. Model II included also the following clinically assessed variables: motor symptoms, cognitive functions, gait speed, dual-task difficulties and functional balance performance as well as reactive postural responses. Results Both regression models showed that the strongest contributing factor to FOF was walking difficulties, i.e. explaining 60% and 64% of the variance in FOF-scores, respectively. Other significant independent variables in both models were needing help from others in daily activities and fatigue. Functional balance was the only clinical variable contributing additional significant information to model I, increasing the explained variance from 66% to 73%. Conclusions The results imply that one should primarily target walking difficulties in daily life in order to reduce FOF in people mildly affected by PD. This finding applies even when considering a broad variety of aspects not previously considered in PD-studies targeting FOF. Functional balance performance, dependence in daily activities, and fatigue were also independently associated with FOF, but to a lesser extent. Longitudinal studies are warranted to gain an increased understanding of predictors of FOF in PD and who is at risk of developing a FOF. PMID:24456482
One-Class Classification-Based Real-Time Activity Error Detection in Smart Homes.
Das, Barnan; Cook, Diane J; Krishnan, Narayanan C; Schmitter-Edgecombe, Maureen
2016-08-01
Caring for individuals with dementia is frequently associated with extreme physical and emotional stress, which often leads to depression. Smart home technology and advances in machine learning techniques can provide innovative solutions to reduce caregiver burden. One key service that caregivers provide is prompting individuals with memory limitations to initiate and complete daily activities. We hypothesize that sensor technologies combined with machine learning techniques can automate the process of providing reminder-based interventions. The first step towards automated interventions is to detect when an individual faces difficulty with activities. We propose machine learning approaches based on one-class classification that learn normal activity patterns. When we apply these classifiers to activity patterns that were not seen before, the classifiers are able to detect activity errors, which represent potential prompt situations. We validate our approaches on smart home sensor data obtained from older adult participants, some of whom faced difficulties performing routine activities and thus committed errors.
Functional anatomy of listening and reading comprehension during development.
Berl, Madison M; Duke, Elizabeth S; Mayo, Jessica; Rosenberger, Lisa R; Moore, Erin N; VanMeter, John; Ratner, Nan Bernstein; Vaidya, Chandan J; Gaillard, William Davis
2010-08-01
Listening and reading comprehension of paragraph-length material are considered higher-order language skills fundamental to social and academic functioning. Using ecologically relevant language stimuli that were matched for difficulty according to developmental level, we analyze the effects of task, age, neuropsychological skills, and post-task performance on fMRI activation and hemispheric laterality. Areas of supramodal language processing are identified, with the most robust region being left-lateralized activation along the superior temporal sulcus. Functionally, this conjunction has a role in semantic and syntactic processing, leading us to refer to this conjunction as "comprehension cortex." Different from adults, supramodal areas for children include less extensive inferior frontal gyrus but more extensive right cerebellum and right temporal pole. Broader neuroanatomical pathways are recruited for reading, reflecting the more active processing and larger set of cognitive demands needed for reading compared to listening to stories. ROI analyses reveal that reading is a less lateralized language task than listening in inferior frontal and superior temporal areas, which likely reflects the difficulty of the task as children in this study are still developing their reading skills. For listening to stories, temporal activation is stable by age four with no correlations with age, neuropsychological skills or post-task performance. In contrast, frontal activation during listening to stories occurs more often in older children, and frontal activation is positively correlated with better performance on comprehension questions, suggesting that the activation of frontal networks may reflect greater integration and depth of story processing. 2010 Elsevier Inc. All rights reserved.
Neural correlates of working memory performance in primary insomnia.
Drummond, Sean P A; Walker, Matthew; Almklov, Erin; Campos, Manuel; Anderson, Dane E; Straus, Laura D
2013-09-01
To examine neural correlates of working memory performance in patients with primary insomnia (PIs) compared with well-matched good sleepers (GSs). Twenty-five PIs and 25 GSs underwent functional MRI while performing an N-back working memory task. VA hospital sleep laboratory and University-based functional imaging center. 25 PIs, 25 GSs. N/A. Although PIs did not differ from GSs in cognitive performance, PIs showed the expected differences from GSs in both self-reported and objective sleep measures. PIs, relative to GSs, showed reduced activation of task-related working memory regions. This manifested both as an overall reduction in activation of task-related regions and specifically as reduced modulation of right dorsolateral prefrontal cortex with increasing task difficulty. Similarly, PIs showed reduced modulation (i.e., reduced deactivation) of default mode regions with increasing task difficulty, relative to GSs. However, PIs showed intact performance. These data establish a profile of abnormal neural function in primary insomnia, reflected both in reduced engagement of task-appropriate brain regions and an inability to modulate task-irrelevant (i.e., default mode) brain areas during working memory performance. These data have implications for better understanding the neuropathophysiology of the well established, yet little understood, discrepancy between ubiquitous subjective cognitive complaints in primary insomnia and the rarely found objective deficits during testing.
Glaucoma and disability: which tasks are affected, and at what stage of disease?
Ramulu, Pradeep
2009-03-01
To summarize recent work from clinical and epidemiological studies that describe how, and at what stage, glaucoma affects the performance of important vision-related activities. Difficulties with the extremes of lighting are the most frequent complaint in glaucoma. Individuals with bilateral glaucoma also self-report difficulty with a broad array of tasks, including reading, walking, and driving. Bilateral glaucoma is associated with driving cessation and limitation, bumping into objects, slower walking, and falls. Some, but not all, studies also demonstrate higher accident rates in glaucoma. Measurable effects on reading speed have only been observed with field damage severe enough to affect binocular central acuity. Glaucoma with bilateral visual field loss is associated with increased symptoms and a measurable decline in mobility and driving. Further work is necessary to establish whether unilateral glaucoma has a significant impact on patients, to determine whether reading difficulty is common in patients with bilateral glaucoma, and to establish the effects of lighting conditions on task performance in glaucoma.
Use of Video Modeling to Teach Weight Lifting Techniques to Adults with Down Syndrome: A Pilot Study
ERIC Educational Resources Information Center
Carter, Kathleen; Pennington, Robert; Ledford, Elizabeth
2017-01-01
As adults with Down syndrome (DS) age, their strength decreases resulting in difficulty performing activities of daily living. In the current study, we investigated the use of video modeling for teaching three adults with DS to perform weight lifting techniques. A multiple probe design across behaviors (i.e., lifts) was used to evaluate…
Toward a mathematical formalism of performance, task difficulty, and activation
NASA Technical Reports Server (NTRS)
Samaras, George M.
1988-01-01
The rudiments of a mathematical formalism for handling operational, physiological, and psychological concepts are developed for use by the man-machine system design engineer. The formalism provides a framework for developing a structured, systematic approach to the interface design problem, using existing mathematical tools, and simplifying the problem of telling a machine how to measure and use performance.
Vázquez, Alexandra; Yzerbyt, Vincent; Dovidio, John F; Gómez, Ángel
2017-12-01
Previous research indicates that meta-stereotypes are predominantly negative. However, the valence of the meta-stereotypes may not be the only factor accounting for the detrimental effects associated with their activation. In addition to valence, we propose that the subjective difficulty of retrieving the meta-stereotype might critically determine whether its activation deteriorates intergroup orientations. An experimental study showed that the effect of the meta-stereotype activation on the desire to interact with outgroup members was moderated by the interaction between the valence of the meta-stereotype and its difficulty of retrieval. In particular, the activation of a positive meta-stereotype deteriorated intergroup orientations when the difficulty of retrieval was high as compared with a condition in which the difficulty of retrieval was low. In sharp contrast, the activation of a negative meta-stereotype worsened intergroup orientations when the difficulty of retrieval was low as compared with a condition in which the difficulty of retrieval was high. © 2016 International Union of Psychological Science.
A SIMPLE FRAILTY QUESTIONNAIRE (FRAIL) PREDICTS OUTCOMES IN MIDDLE AGED AFRICAN AMERICANS
MORLEY, J.E.; MALMSTROM, T.K.; MILLER, D.K.
2015-01-01
Objective To validate the FRAIL scale. Design Longitudinal study. Setting Community. Participants Representative sample of African Americans age 49 to 65 years at onset of study. Measurements The 5-item FRAIL scale (Fatigue, Resistance, Ambulation, Illnesses, & Loss of Weight), at baseline and activities of daily living (ADLs), instrumental activities of daily living (IADLs), mortality, short physical performance battery (SPPB), gait speed, one-leg stand, grip strength and injurious falls at baseline and 9 years. Blood tests for CRP, SIL6R, STNFR1, STNFR2 and 25 (OH) vitamin D at baseline. Results Cross-sectionally the FRAIL scale correlated significantly with IADL difficulties, SPPB, grip strength and one-leg stand among participants with no baseline ADL difficulties (N=703) and those outcomes plus gait speed in those with no baseline ADL dependencies (N=883). TNFR1 was increased in pre-frail and frail subjects and CRP in some subgroups. Longitudinally (N=423 with no baseline ADL difficulties or N=528 with no baseline ADL dependencies), and adjusted for the baseline value for each outcome, being pre-frail at baseline significantly predicted future ADL difficulties, worse one-leg stand scores, and mortality in both groups, plus IADL difficulties in the dependence-excluded group. Being frail at baseline significantly predicted future ADL difficulties, IADL difficulties, and mortality in both groups, plus worse SPPB in the dependence-excluded group. Conclusion This study has validated the FRAIL scale in a late middle-aged African American population. This simple 5-question scale is an excellent screening test for clinicians to identify frail persons at risk of developing disability as well as decline in health functioning and mortality. PMID:22836700
On how high performers keep cool brains in situations of cognitive overload.
Jaeggi, Susanne M; Buschkuehl, Martin; Etienne, Alex; Ozdoba, Christoph; Perrig, Walter J; Nirkko, Arto C
2007-06-01
What happens in the brain when we reach or exceed our capacity limits? Are there individual differences for performance at capacity limits? We used functional magnetic resonance imaging (fMRI) to investigate the impact of increases in processing demand on selected cortical areas when participants performed a parametrically varied and challenging dual task. Low-performing participants respond with large and load-dependent activation increases in many cortical areas when exposed to excessive task requirements, accompanied by decreasing performance. It seems that these participants recruit additional attentional and strategy-related resources with increasing difficulty, which are either not relevant or even detrimental to performance. In contrast, the brains of the high-performing participants "keep cool" in terms of activation changes, despite continuous correct performance, reflecting different and more efficient processing. These findings shed light on the differential implications of performance on activation patterns and underline the importance of the interindividual-differences approach in neuroimaging research.
Hyperbrain features of team mental models within a juggling paradigm: a proof of concept
Filho, Edson; Tamburro, Gabriella; Schinaia, Lorenzo; Chatel-Goldman, Jonas; di Fronso, Selenia; Robazza, Claudio
2016-01-01
Background Research on cooperative behavior and the social brain exists, but little research has focused on real-time motor cooperative behavior and its neural correlates. In this proof of concept study, we explored the conceptual notion of shared and complementary mental models through EEG mapping of two brains performing a real-world interactive motor task of increasing difficulty. We used the recently introduced participative “juggling paradigm,” and collected neuro-physiological and psycho-social data. We were interested in analyzing the between-brains coupling during a dyadic juggling task, and in exploring the relationship between the motor task execution, the jugglers’skill level and the task difficulty. We also investigated how this relationship could be mirrored in the coupled functional organization of the interacting brains. Methods To capture the neural schemas underlying the notion of shared and complementary mental models, we examined the functional connectivity patterns and hyperbrain features of a juggling dyad involved in cooperative motor tasks of increasing difficulty. Jugglers’ cortical activity was measured using two synchronized 32-channel EEG systems during dyadic juggling performed with 3, 4, 5 and 6 balls. Individual and hyperbrain functional connections were quantified through coherence maps calculated across all electrode pairs in the theta and alpha bands (4–8 and 8–12 Hz). Graph metrics were used to typify the global topology and efficiency of the functional networks for the four difficulty levels in the theta and alpha bands. Results Results indicated that, as task difficulty increased, the cortical functional organization of the more skilled juggler became progressively more segregated in both frequency bands, with a small-world organization in the theta band during easier tasks, indicative of a flow-like state in line with the neural efficiency hypothesis. Conversely, more integrated functional patterns were observed for the less skilled juggler in both frequency bands, possibly related to cognitive overload due to the difficulty of the task at hand (reinvestment hypothesis). At the hyperbrain level, a segregated functional organization involving areas of the visuo-attentional networks of both jugglers was observed in both frequency bands and for the easier task only. Discussion These results suggest that cooperative juggling is supported by integrated activity of specialized cortical areas from both brains only during easier tasks, whereas it relies on individual skills, mirrored in uncorrelated individual brain activations, during more difficult tasks. These findings suggest that task difficulty and jugglers’ personal skills may influence the features of the hyperbrain network in its shared/integrative and complementary/segregative tendencies. PMID:27688968
Silverstein, S M; All, S D; Kasi, R; Berten, S; Essex, B; Lathrop, K L; Little, D M
2010-07-01
People with schizophrenia demonstrate perceptual organization impairments, and these are thought to contribute to their face processing difficulties. We examined the neural substrates of emotionally neutral face processing in schizophrenia by investigating neural activity under three stimulus conditions: faces characterized by the full spectrum of spatial frequencies, faces with low spatial frequency information removed [high spatial frequency (HSF) condition], and faces with high spatial frequency information removed [low spatial frequency (LSF) condition]. Face perception in the HSF condition is more reliant on local feature processing whereas perception in the LSF condition requires greater reliance on global form processing. Past studies of perceptual organization in schizophrenia indicate that patients perform relatively more poorly with degraded stimuli but also that, when global information is absent, patients may perform better than controls because of their relatively increased ability to initially process individual features. Therefore, we hypothesized that people with schizophrenia (n=14) would demonstrate greater face processing difficulties than controls (n=13) in the LSF condition, whereas they would demonstrate a smaller difference or superior performance in the HSF condition. In a gender-discrimination task, behavioral data indicated high levels of accuracy for both groups, with a trend toward an interaction involving higher patient performance in the HSF condition and poorer patient performance in the LSF condition. Patients demonstrated greater activity in the fusiform gyrus compared to controls in both degraded conditions. These data suggest that impairments in basic integration abilities may be compensated for by relatively increased activity in this region.
Influence of stationary lateral vibrations on train passengers' difficulty to read and write.
Sundström, Jerker; Khan, Shafiquzzaman
2008-11-01
Recent studies on train passengers' activities found that many passengers were engaged in some form of work, e.g. reading and writing, while traveling by train. A majority of the passengers reported that they were disturbed by vibrations or motions during their journey. A laboratory study was therefore set up to study how stationary low-frequency lateral vibrations influence the difficulty to read and write. The study involved 48 subjects (24f+24m) divided into three age groups. Two levels of sinusoidal vibrations were applied at nine discrete frequencies (0.8-8.0 Hz). Subjects performed both reading and writing tasks under two sitting positions (leaning against the backrest and leaning over a table). The judgments of perceived difficulty to read and write were rated using Borg's CR-100 scale. The results showed significant differences between the tasks and postural conditions. The subjects reported greater difficulty while reading and writing on the table than while leaning back. The frequencies up to 5 Hz had a particular influence on the perceived difficulty.
Potts, Tiffany M; Nguyen, Jacqueline L; Ghai, Kanika; Li, Kathy; Perlmuter, Lawrence
2015-04-15
To investigate whether perceptions of task difficulty on neuropsychological tests predicted academic achievement after controlling for glucose levels and depression. Participants were type 1 diabetic adolescents, with a mean age = 12.5 years (23 females and 16 males), seen at a northwest suburban Chicago hospital. The sample population was free of co-morbid clinical health conditions. Subjects completed a three-part neuropsychological battery including the Digit Symbol Task, Trail Making Test, and Controlled Oral Word Association test. Following each task, individuals rated task difficulty and then completed a depression inventory. Performance on these three tests is reflective of neuropsychological status in relation to glucose control. Blood glucose levels were measured immediately prior to and after completing the neuropsychological battery using a glucose meter. HbA1c levels were obtained from medical records. Academic performance was based on self-reported grades in Math, Science, and English. Data was analyzed using multiple regression models to evaluate the associations between academic performance, perception of task difficulty, and glucose control. Perceptions of difficulty on a neuropsychological battery significantly predicted academic performance after accounting for glucose control and depression. Perceptions of difficulty on the neuropsychological tests were inversely correlated with academic performance (r = -0.48), while acute (blood glucose) and long-term glucose levels increased along with perceptions of task difficulty (r = 0.47). Additionally, higher depression scores were associated with poorer academic performance (r = -0.43). With the first regression analysis, perception of difficulty on the neuropsychological tasks contributed to 8% of the variance in academic performance after controlling for peripheral blood glucose and depression. In the second regression analysis, perception of difficulty accounted for 11% of the variance after accounting for academic performance and depression. The final regression analysis indicated that perception of difficulty increased with peripheral blood glucose, contributing to 22% of the variance. Most importantly, after controlling for perceptions of task difficulty, academic performance no longer predicted glucose levels. Finally, subjects who found the cognitive battery difficult were likely to have poor academic grades. Perceptions of difficulty on neurological tests exhibited a significant association with academic achievement, indicating that deficits in this skill may lead to academic disadvantage in diabetic patients.
Tian, Yu; Bian, Yulong; Han, Piguo; Wang, Peng; Gao, Fengqiang; Chen, Yingmin
2017-01-01
Flow is the experience of effortless attention, reduced self-consciousness, and a deep sense of control that typically occurs during the optimal performance of challenging tasks. On the basis of the person-artifact-task model, we selected computer games (tasks) with varying levels of difficulty (difficult, medium, and easy) and shyness (personality) as flow precursors to study the physiological activity of users in a flow state. Cardiac and respiratory activity and mean changes in skin conductance (SC) were measured continuously while the participants ( n = 40) played the games. Moreover, the associations between self-reported psychological flow and physiological measures were investigated through a series of repeated-measures analyses. The results showed that the flow experience is related to a faster respiratory rate, deeper respiration, moderate heart rate (HR), moderate HR variability, and moderate SC. The main effect of shyness was non-significant, whereas the interaction of shyness and difficulty influenced the flow experience. These findings are discussed in relation to current models of arousal and valence. The results indicate that the flow state is a state of moderate mental effort that arises through the increased parasympathetic modulation of sympathetic activity.
Malhotra, Rahul; Chan, Angelique; Ajay, Shweta; Ma, Stefan; Saito, Yasuhiko
2016-10-01
To assess variation in gender gap (female-male) in inactive life expectancy (IALE) and active life expectancy (ALE) by definition of inactivity. Inactivity, among older Singaporeans, was defined as follows: Scenario 1-health-related difficulty in activities of daily living (ADLs); Scenario 2-health-related difficulty in ADLs/instrumental ADLs (IADLs); Scenario 3-health-related difficulty in ADLs/IADLs or non-health-related non-performance of IADLs. Multistate life tables computed IALE and ALE at age 60, testing three hypotheses: In all scenarios, life expectancy, absolute and relative IALE, and absolute ALE are higher for females (Hypothesis 1 [H1]); gender gap in absolute and relative IALE expands, and in absolute ALE, it contracts in Scenario 2 versus 1 (Hypothesis 2 [H2]); gender gap in absolute and relative IALE decreases, and in absolute ALE, it increases in Scenario 3 versus 2 (Hypothesis 3 [H3]). H1 was supported in Scenarios 1 and 3 but not Scenario 2. Both H2 and H3 were supported. Definition of inactivity influences gender gap in IALE and ALE. © The Author(s) 2016.
Tian, Yu; Bian, Yulong; Han, Piguo; Wang, Peng; Gao, Fengqiang; Chen, Yingmin
2017-01-01
Flow is the experience of effortless attention, reduced self-consciousness, and a deep sense of control that typically occurs during the optimal performance of challenging tasks. On the basis of the person–artifact–task model, we selected computer games (tasks) with varying levels of difficulty (difficult, medium, and easy) and shyness (personality) as flow precursors to study the physiological activity of users in a flow state. Cardiac and respiratory activity and mean changes in skin conductance (SC) were measured continuously while the participants (n = 40) played the games. Moreover, the associations between self-reported psychological flow and physiological measures were investigated through a series of repeated-measures analyses. The results showed that the flow experience is related to a faster respiratory rate, deeper respiration, moderate heart rate (HR), moderate HR variability, and moderate SC. The main effect of shyness was non-significant, whereas the interaction of shyness and difficulty influenced the flow experience. These findings are discussed in relation to current models of arousal and valence. The results indicate that the flow state is a state of moderate mental effort that arises through the increased parasympathetic modulation of sympathetic activity. PMID:28725206
Vaag, Jonas; Saksvik-Lehouillier, Ingvild; Bjørngaard, Johan Håkon; Bjerkeset, Ottar
2016-01-01
Sleep problems are reported as common among performing artists and musicians. However, epidemiological research comparing musicians to different groups of the general population is lacking. For this study, 4,168 members of the Norwegian Musician's Union were invited to an online survey regarding work and health. Of the 2,121 (51%) respondents, 1,607 were active performing musicians. We measured prevalence of insomnia symptoms using the Bergen Insomnia Scale (BIS), and compared this sample to a representative sample of the general Norwegian population (n = 2,645). Overall, musicians had higher prevalence of insomnia symptoms compared to the general population (Prevalence Difference 6.9, 95% Confidence Interval 3.9-10.0). Item response analysis showed that this difference was mainly explained by nonrestorative sleep and dissatisfaction with sleep among musicians. An additional analysis, comparing musicians to the general Norwegian workforce (n = 8,518) on sleep difficulties, confirmed this tendency (Prevalence Difference 6.2, 95% Confidence Interval 4.3-8.1). Musicians performing classical, contemporary, rock, and country music reported the highest prevalence of insomnia, and these genres might be of special interest when developing preventative measures, treatment strategies, and further research on sleep difficulties among musicians.
Ahlstrand, Inger; Vaz, Sharmila; Falkmer, Torbjörn; Thyberg, Ingrid; Björk, Mathilda
2017-06-01
To study whether personal factors (self-efficacy and pain acceptance) mediate the relationship between pain and performance of valued life activities in persons with rheumatoid arthritis. Persons with rheumatoid arthritis for at least four years ( n = 737; 73% women) answered a questionnaire measuring self-efficacy, pain acceptance, performance of valued life activities, and self-rated pain. Relationships among these constructs were explored using univariate and multivariate analyses. Structural equation modelling was then used to examine the mediational role of personal factors on the relationship between pain and performance of valued life activities. A direct negative association between pain and performance of valued life activities was identified ( Beta = .34, P < .001). This suggests that people with rheumatoid arthritis who had higher levels of pain has increased difficulties in performing valued life activities. Self-efficacy and activity engagement component of pain acceptance mediated the relationship between pain and performance of valued life activities, however the pain willingness component of pain acceptance did not influence participation in valued life activities. These findings highlight the importance of considering personal factors, such as pain acceptance and self-efficacy, in facilitating participation in valued life activities.
Sanli, Elizabeth A; Lee, Timothy D
2015-06-01
The influence of nominal and functional task difficulty during the acquisition of a motor skill was examined in two tests of transfer of learning. The task involved a ballistic, target-directed, finger action. Nominal task difficulty was defined as the distance of the target from the home position. Functional task difficulty was created by manipulating the progression of target distances during practice. Based on the challenge point framework (Guadagnoli & Lee, 2004), we predicted that practice with a set of targets farther away from the performer would benefit from less functional task difficulty, while practice with a closer set of targets would benefit from more functional task difficulty. In single-task transfer tests, learners who practiced using the high nominal task difficulty targets benefitted in terms of persistence of performance over time. In dual-task transfer tests, groups with an intermediate combined (nominal and functional) task difficulty performed with greater persistence over time on tests of transfer than those who practiced with the highest or lowest combined difficulty. Together these findings suggest that the influences of nominal and functional task difficulty during acquisition are weighted differentially depending upon the transfer test context. The challenge point framework does not accurately capture this complex relationship in its current form. Copyright © 2015 Elsevier B.V. All rights reserved.
The ACTIVE conceptual framework as a structural equation model
Gross, Alden L.; Payne, Brennan R.; Casanova, Ramon; Davoudzadeh, Pega; Dzierzewski, Joseph M.; Farias, Sarah; Giovannetti, Tania; Ip, Edward H.; Marsiske, Michael; Rebok, George W.; Schaie, K. Warner; Thomas, Kelsey; Willis, Sherry; Jones, Richard N.
2018-01-01
Background/Study Context Conceptual frameworks are analytic models at a high level of abstraction. Their operationalization can inform randomized trial design and sample size considerations. Methods The Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) conceptual framework was empirically tested using structural equation modeling (N=2,802). ACTIVE was guided by a conceptual framework for cognitive training in which proximal cognitive abilities (memory, inductive reasoning, speed of processing) mediate treatment-related improvement in primary outcomes (everyday problem-solving, difficulty with activities of daily living, everyday speed, driving difficulty), which in turn lead to improved secondary outcomes (health-related quality of life, health service utilization, mobility). Measurement models for each proximal, primary, and secondary outcome were developed and tested using baseline data. Each construct was then combined in one model to evaluate fit (RMSEA, CFI, normalized residuals of each indicator). To expand the conceptual model and potentially inform future trials, evidence of modification of structural model parameters was evaluated by age, years of education, sex, race, and self-rated health status. Results Preconceived measurement models for memory, reasoning, speed of processing, everyday problem-solving, instrumental activities of daily living (IADL) difficulty, everyday speed, driving difficulty, and health-related quality of life each fit well to the data (all RMSEA < .05; all CFI > .95). Fit of the full model was excellent (RMSEA = .038; CFI = .924). In contrast with previous findings from ACTIVE regarding who benefits from training, interaction testing revealed associations between proximal abilities and primary outcomes are stronger on average by nonwhite race, worse health, older age, and less education (p < .005). Conclusions Empirical data confirm the hypothesized ACTIVE conceptual model. Findings suggest that the types of people who show intervention effects on cognitive performance potentially may be different from those with the greatest chance of transfer to real-world activities. PMID:29303475
Choi, Younggeun; Gordon, James; Park, Hyeshin; Schweighofer, Nicolas
2011-08-03
Current guidelines for rehabilitation of arm and hand function after stroke recommend that motor training focus on realistic tasks that require reaching and manipulation and engage the patient intensively, actively, and adaptively. Here, we investigated the feasibility of a novel robotic task-practice system, ADAPT, designed in accordance with such guidelines. At each trial, ADAPT selects a functional task according to a training schedule and with difficulty based on previous performance. Once the task is selected, the robot picks up and presents the corresponding tool, simulates the dynamics of the tasks, and the patient interacts with the tool to perform the task. Five participants with chronic stroke with mild to moderate impairments (> 9 months post-stroke; Fugl-Meyer arm score 49.2 ± 5.6) practiced four functional tasks (selected out of six in a pre-test) with ADAPT for about one and half hour and 144 trials in a pseudo-random schedule of 3-trial blocks per task. No adverse events occurred and ADAPT successfully presented the six functional tasks without human intervention for a total of 900 trials. Qualitative analysis of trajectories showed that ADAPT simulated the desired task dynamics adequately, and participants reported good, although not excellent, task fidelity. During training, the adaptive difficulty algorithm progressively increased task difficulty leading towards an optimal challenge point based on performance; difficulty was then continuously adjusted to keep performance around the challenge point. Furthermore, the time to complete all trained tasks decreased significantly from pretest to one-hour post-test. Finally, post-training questionnaires demonstrated positive patient acceptance of ADAPT. ADAPT successfully provided adaptive progressive training for multiple functional tasks based on participant's performance. Our encouraging results establish the feasibility of ADAPT; its efficacy will next be tested in a clinical trial.
Applicability Evaluation of Job Standards for Diabetes Nutritional Management by Clinical Dietitian.
Baek, Young Jin; Oh, Na Gyeong; Sohn, Cheong-Min; Woo, Mi-Hye; Lee, Seung Min; Ju, Dal Lae; Seo, Jung-Sook
2017-04-01
This study was conducted to evaluate applicability of job standards for diabetes nutrition management by hospital clinical dietitians. In order to promote the clinical nutrition services, it is necessary to present job standards of clinical dietitian and to actively apply these standardized tasks to the medical institution sites. The job standard of clinical dietitians for diabetic nutrition management was distributed to hospitals over 300 beds. Questionnaire was collected from 96 clinical dietitians of 40 tertiary hospitals, 47 general hospitals, and 9 hospitals. Based on each 5-point scale, the importance of overall duty was 4.4 ± 0.5, performance was 3.6 ± 0.8, and difficulty was 3.1 ± 0.7. 'Nutrition intervention' was 4.5 ± 0.5 for task importance, 'nutrition assessment' was 4.0 ± 0.7 for performance, and 'nutrition diagnosis' was 3.4 ± 0.9 for difficulty. These 3 items were high in each category. Based on the grid diagram, the tasks of both high importance and high performance were 'checking basic information,' 'checking medical history and therapy plan,' 'decision of nutritional needs,' 'supply of foods and nutrients,' and 'education of nutrition and self-management.' The tasks with high importance but low performance were 'derivation of nutrition diagnosis,' 'planning of nutrition intervention,' 'monitoring of nutrition intervention process.' The tasks of both high importance and high difficulty were 'derivation of nutrition diagnosis,' 'planning of nutrition intervention,' 'supply of foods and nutrients,' 'education of nutrition and self-management,' and 'monitoring of nutrition intervention process.' The tasks of both high performance and high difficulty were 'documentation of nutrition assessment,' 'supply of foods and nutrients,' and 'education of nutrition and self-management.'
Care Challenges in the Bathroom: The Views of Professional Care Providers Working in Clients' Homes.
King, Emily C; Holliday, Pamela J; Andrews, Gavin J
2018-04-01
In home care, bathroom activities-particularly bathing and toileting-present a unique set of challenges. In this focus group study, professional home care providers identified factors that increase the danger and difficulty of assisting their clients with bathing and toileting. These included small restrictive spaces, a poor fit between available equipment and the environment, a reliance on manual handling techniques (but insufficient space to use optimal body mechanics), attempts to maintain normalcy, and caring for unsteady and unpredictable clients. Specific elements of each activity that care providers found difficult included multitasking to support client stability while performing care below the waist (dressing/undressing, providing perineal care) and helping clients to lift their legs in and out of a bathtub. Participants did not feel that available assistive devices provided enough assistance to reduce the danger and difficulty of these activities.
Source localization in electromyography using the inverse potential problem
NASA Astrophysics Data System (ADS)
van den Doel, Kees; Ascher, Uri M.; Pai, Dinesh K.
2011-02-01
We describe an efficient method for reconstructing the activity in human muscles from an array of voltage sensors on the skin surface. MRI is used to obtain morphometric data which are segmented into muscle tissue, fat, bone and skin, from which a finite element model for volume conduction is constructed. The inverse problem of finding the current sources in the muscles is solved using a careful regularization technique which adds a priori information, yielding physically reasonable solutions from among those that satisfy the basic potential problem. Several regularization functionals are considered and numerical experiments on a 2D test model are performed to determine which performs best. The resulting scheme leads to numerical difficulties when applied to large-scale 3D problems. We clarify the nature of these difficulties and provide a method to overcome them, which is shown to perform well in the large-scale problem setting.
Garrett, Stephanie L; Sawyer, Patricia; Kennedy, Richard E; McGuire, Dawn; Simon, Roger P; Strothers, Harry S; Allman, Richard M
2013-12-01
To examine the association between function measured according to activities of daily living (ADLs), instrumental activ1ities of daily living (IADLs), and cognition assessed according to Mini-Mental State Examination (MMSE) scores of older African-American and non-Hispanic white community-dwelling men and women. Cross-sectional study assessing associations between self-reported ADL and IADL difficulty and MMSE scores for race- and sex-specific groups. Homes of community-dwelling older adults. A random sample of 974 African-American and non-Hispanic white Medicare beneficiaries aged 65 and older living in west-central Alabama and participating in the University of Alabama at Birmingham Study of Aging, excluding those with reported diagnoses of dementia or with missing data. Function, based on self-reported difficulty in performing ADLs and IADLs, and cognition, using the MMSE. Multivariable linear regression models were used to test the association between function and cognition in race- and sex-specific groups after adjusting for covariates. Mini-Mental State Examination scores were modestly correlated with ADL and IADL difficulty in all four race- and sex-specific groups, with Pearson correlation coefficients ranging from −0.189 for non-Hispanic white women to −0.429 for African-American men. Correlations between MMSE and ADL or IADL difficulty in any of the race- and sex-specific groups were no longer significant after controlling for sociodemographic factors and comorbidities. Mini-Mental State Examination was not significantly associated with functional difficulty in older African-American and non-Hispanic white men and women after adjusting for sociodemographic factors and comorbidities, suggesting a mediating role in the relationship between cognition and function. © 2013, Copyright the Authors Journal compilation © 2013, The American Geriatrics Society.
Walitt, Brian; Čeko, Marta; Khatiwada, Manish; Gracely, John L.; Rayhan, Rakib; VanMeter, John W.; Gracely, Richard H.
2016-01-01
The subjective experience of cognitive dysfunction (“fibrofog”) is common in fibromyalgia. This study investigated the relation between subjective appraisal of cognitive function, objective cognitive task performance, and brain activity during a cognitive task using functional magnetic resonance imaging (fMRI). Sixteen fibromyalgia patients and 13 healthy pain-free controls completed a battery of questionnaires, including the Multiple Ability Self-Report Questionnaire (MASQ), a measure of self-perceived cognitive difficulties. Participants were evaluated for working memory performance using a modified N-back working memory task while undergoing Blood Oxygen Level Dependent (BOLD) fMRI measurements. Fibromyalgia patients and controls did not differ in working memory performance. Subjective appraisal of cognitive function was associated with better performance (accuracy) on the working memory task in healthy controls but not in fibromyalgia patients. In fibromyalgia patients, increased perceived cognitive difficulty was positively correlated with the severity of their symptoms. BOLD response during the working memory task did not differ between the groups. BOLD response correlated with task accuracy in control subjects but not in fibromyalgia patients. Increased subjective cognitive impairment correlated with decreased BOLD response in both groups but in different anatomic regions. In conclusion, “fibrofog” appears to be better characterized by subjective rather than objective impairment. Neurologic correlates of this subjective experience of impairment might be separate from those involved in the performance of cognitive tasks. PMID:26955513
Walitt, Brian; Čeko, Marta; Khatiwada, Manish; Gracely, John L; Rayhan, Rakib; VanMeter, John W; Gracely, Richard H
2016-01-01
The subjective experience of cognitive dysfunction ("fibrofog") is common in fibromyalgia. This study investigated the relation between subjective appraisal of cognitive function, objective cognitive task performance, and brain activity during a cognitive task using functional magnetic resonance imaging (fMRI). Sixteen fibromyalgia patients and 13 healthy pain-free controls completed a battery of questionnaires, including the Multiple Ability Self-Report Questionnaire (MASQ), a measure of self-perceived cognitive difficulties. Participants were evaluated for working memory performance using a modified N-back working memory task while undergoing Blood Oxygen Level Dependent (BOLD) fMRI measurements. Fibromyalgia patients and controls did not differ in working memory performance. Subjective appraisal of cognitive function was associated with better performance (accuracy) on the working memory task in healthy controls but not in fibromyalgia patients. In fibromyalgia patients, increased perceived cognitive difficulty was positively correlated with the severity of their symptoms. BOLD response during the working memory task did not differ between the groups. BOLD response correlated with task accuracy in control subjects but not in fibromyalgia patients. Increased subjective cognitive impairment correlated with decreased BOLD response in both groups but in different anatomic regions. In conclusion, "fibrofog" appears to be better characterized by subjective rather than objective impairment. Neurologic correlates of this subjective experience of impairment might be separate from those involved in the performance of cognitive tasks.
Obremskey, William; Agel, Julie; Archer, Kristin; To, Philip; Tornetta, Paul
2015-01-01
Objective To study the activity and incidence of knee pain after sustaining a isolated tibia fracture treated with an infrapatellar intramedullary nail at one year. Design Retrospective review of prospective cohort Setting Multicenter Academic and Community hospitals Patients 437 patients with an isolated tibia fracture completed a 12 month assessment on pain and self-reported activity. Intervention Infrapatellar Intramedullary Nail Outcomes Demographic information co-morbid conditions, injury characteristics, and surgical technique were recorded. Knee pain was defined on a 1-7 scale with 1 being “no pain” and 7 being a “very great deal of pain.” Knee pain > 4 was considered clinically significant. Patients reported if they were “able”, “able with difficulty” or “unable” to perform the following activities: kneel, run, climb stairs, and walk prolonged. Variables were tested in multilevel multivariable regression analyses. Results Knee Pain: 11% percent of patients reported a “good deal” to a “very great deal” of pain (> 4). 52% of patients reported “no” or “very little” pain at 12 months. Activity at 12 months: 26% and 29% of patients were unable to kneel or run, respectively. 31% and 35% of patients respectively stated they were able with difficulty or unable to use stairs or walk. Conclusion Clinically significant knee pain (>4/7) was present in 11% of patients one year after a tibia fracture. 31%-71% of patients had difficulty performing or were unable to perform routine daily activities of kneeling, running, and stair climbing or walking prolonged distances. PMID:26496180
Taillade, Mathieu; Sauzéon, Hélène; Dejos, Marie; Pala, Prashant Arvind; Larrue, Florian; Wallet, Grégory; Gross, Christian; N'Kaoua, Bernard
2013-01-01
The aim of this study was to evaluate in large-scale spaces wayfinding and spatial learning difficulties for older adults in relation to the executive and memory decline associated with aging. We compared virtual reality (VR)-based wayfinding and spatial memory performances between young and older adults. Wayfinding and spatial memory performances were correlated with classical measures of executive and visuo-spatial memory functions, but also with self-reported estimates of wayfinding difficulties. We obtained a significant effect of age on wayfinding performances but not on spatial memory performances. The overall correlations showed significant correlations between the wayfinding performances and the classical measures of both executive and visuo-spatial memory, but only when the age factor was not partialled out. Also, older adults underestimated their wayfinding difficulties. A significant relationship between the wayfinding performances and self-reported wayfinding difficulty estimates is found, but only when the age effect was partialled out. These results show that, even when older adults have an equivalent spatial knowledge to young adults, they had greater difficulties with the wayfinding task, supporting an executive decline view in age-related wayfinding difficulties. However, the correlation results are in favor of both the memory and executive decline views as mediators of age-related differences in wayfinding performances. This is discussed in terms of the relationships between memory and executive functioning in wayfinding task orchestration. Our results also favor the use of objective assessments of everyday navigation difficulties in virtual applications, instead of self-reported questionnaires, since older adults showed difficulties in estimating their everyday wayfinding problems.
Affect-Based Adaptation of an Applied Video Game for Educational Purposes
ERIC Educational Resources Information Center
Bontchev, Boyan; Vassileva, Dessislava
2017-01-01
Purpose: This paper aims to clarify how affect-based adaptation can improve implicit recognition of playing style of individuals during game sessions. This study presents the "Rush for Gold" game using dynamic difficulty adjustment of tasks based on both player performance and affectation inferred through electrodermal activity and…
ERIC Educational Resources Information Center
Harvey, William J.; Wilkinson, Shawn; Pressé, Cindy; Joober, Ridha; Grizenko, Natalie
2014-01-01
Background: Physical educators suggested that they are not well-informed about behaviors of children with disabilities, especially attention-deficit hyperactivity disorder (ADHD). Children with ADHD represent a significant number of students in school systems worldwide who often experience difficulties in performing fundamental movement skills.…
Hughes, Michael G; Day, Eric Anthony; Wang, Xiaoqian; Schuelke, Matthew J; Arsenault, Matthew L; Harkrider, Lauren N; Cooper, Olivia D
2013-01-01
An inherent aspect of learner-controlled instructional environments is the ability of learners to affect the degree of difficulty faced during training. However, research has yet to examine how learner-controlled practice difficulty affects learning. Based on the notion of desirable difficulties (Bjork, 1994), this study examined the cognitive and motivational antecedents and outcomes of learner-controlled practice difficulty in relation to learning a complex task. Using a complex videogame involving both strong cognitive and psychomotor demands, 112 young adult males were given control over their practice difficulty, which was reflected in the complexity of the training task. Results show that general mental ability, prior experience, pre-training self-efficacy, and error encouragement were positively related to learner-controlled practice difficulty. In turn, practice difficulty was directly related to task knowledge and post-training performance, and it was related to adaptive performance through the mediating influences of task knowledge and post-training performance. In general, this study supports the notion that training difficulty operationalized in terms of task complexity is positively related to both knowledge and performance outcomes. Results are discussed with respect to the need for more research examining how task complexity and other forms of difficulty could be leveraged to advance learner-controlled instructional practices. PsycINFO Database Record (c) 2013 APA, all rights reserved.
Larsson Lund, Maria; Nygård, Louise; Kottorp, Anders
2014-01-01
The aim was to explore the relationships between difficulties in the use of everyday technology (ET) and the ability to perform activities of daily life (ADL) in the home and in society and in the workplace in people with acquired brain injury (ABI). The investigation comprises an explorative cross-sectional study of 74 people with ABI. The short version of the Everyday Technology Use Questionnaire (S-ETUQ) and a revised version of the ADL taxonomy were used to evaluate the participants. Rasch-generated person ability measures of ET use and ADL were used in correlation analyses, in group comparisons by ANOVA and in logistic regressions. Difficulty in the use of ET was significantly correlated with ADL limitations. People who worked full- or part-time had significantly higher ability to use ET than those with some type of full-time, long-term sickness compensation. The ability to use ET, ADL ability and age were significantly related to return to work. The ability to use ET is related to all areas of everyday functioning in people with ABI. Therefore, a patient's ability to use ET needs to be considered in rehabilitation strategies following an ABI to enhance the patient's performance of activities in the home and in society and to support his or her likelihood of returning to work.
Bendayan, Rebecca; Cooper, Rachel; Wloch, Elizabeth G; Hofer, Scott M; Piccinin, Andrea M; Muniz-Terrera, Graciela
2017-08-01
We aimed to identify the hierarchy of rates of decline in 16 physical functioning measures in U.S. and English samples, using a systematic and integrative coordinated data analysis approach. The U.S. sample consisted of 13,612 Health and Retirement Study participants, and the English sample consisted of 5,301 English Longitudinal Study of Ageing participants. Functional loss was ascertained using self-reported difficulties performing 6 activities of daily living and 10 mobility tasks. The variables were standardized, rates of decline were computed, and mean rates of decline were ranked. Mann-Whitney U tests were performed to compare rates of decline between studies. In both studies, the rates of decline followed a similar pattern; difficulty with eating was the activity that showed the slowest decline and climbing several flights of stairs and stooping, kneeling, or crouching the fastest declines. There were statistical differences in the speed of decline in all 16 measures between countries. American women had steeper declines in 10 of the measures than English women. Similar differences were found between American and English men. Reporting difficulties climbing several flights of stairs without resting, and stooping, kneeling, or crouching are the first indicators of functional loss reported in both populations. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America.
Non-erotic thoughts, attentional focus, and sexual problems in a community sample.
Nelson, Andrea L; Purdon, Christine
2011-04-01
According to Barlow's model of sexual dysfunction, anxiety in sexual situations leads to attentional focus on sexual performance at the expense of erotic cues, which compromises sexual arousal. This negative experience will enhance anxiety in future sexual situations, and non-erotic thoughts (NETs) relevant to performance will receive attentional priority. Previous research with student samples (Purdon & Holdaway, 2006; Purdon & Watson, 2010) has found that people experience many types of NETs in addition to performance-relevant thoughts, and that, consistent with Barlow's model, the frequency of and anxiety evoked by these thoughts is positively associated with sexual problems. Extending this previous work, the current study found that, in a community sample of women (N = 81) and men (N = 72) in long-term relationships, women were more likely to report body image concerns and external consequences of the sexual activity, while men were more likely to report performance-related concerns. Equally likely among men and women were thoughts about emotional consequences of the sexual activity. Regardless of thought content, experiencing more frequent NETs was associated with more sexual problems in both women and men. Moreover, as per Barlow's model, greater negative affect in anticipation of and during sexual activity predicted greater frequency of NETs and greater anxiety in response to NETs was associated with greater difficulty dismissing the thoughts. However, greater difficulty in refocusing on erotic thoughts during sexual activity uniquely predicted more sexual problems above the frequency and dismissability of NETs. Together, these data support the cognitive interference mechanism implicated by Barlow's causal model of sexual dysfunction and have implications for the treatment of sexual problems.
Social competence and learning difficulties: Teacher perceptions.
Wight, Megan; Chapparo, Christine
2008-12-01
Social competence has been linked to children's classroom performance with three out of four children with learning difficulties reported to have problems with social skills. Social participation remains a predominant childhood occupation and a key indicator of school performance. Occupational therapists work with teachers to accurately assess the social performance of children in context and to provide targeted intervention. There is limited research about what teachers perceive are the specific nature of social difficulties experienced by children with learning difficulties in the classroom. This study investigated teacher perceptions of the social competence of a small sample of Australian boys with learning difficulties within the classroom context. The Teacher Skillstreaming Checklist was used to investigate teacher perceptions of the social abilities of 21 primary school aged boys with learning difficulties compared to a control group. A correlational analysis was used to examine the relationship. The study identified that the boys with learning difficulties were perceived by their teachers as having poorer social performance across multiple domains when compared to their typically developing peers. Implications of these findings are that children's social performance may negatively impact learning and classroom participation and that for some children, social competence should be a focus of occupational therapy assessment and treatment.
Risk of dependence associated with health, social support, and lifestyle
Alcañiz, Manuela; Brugulat, Pilar; Guillén, Montserrat; Medina-Bustos, Antonia; Mompart-Penina, Anna; Solé-Auró, Aïda
2015-01-01
OBJECTIVE To analyze the prevalence of individuals at risk of dependence and its associated factors. METHODS The study was based on data from the Catalan Health Survey, Spain conducted in 2010 and 2011. Logistic regression models from a random sample of 3,842 individuals aged ≥ 15 years were used to classify individuals according to the state of their personal autonomy. Predictive models were proposed to identify indicators that helped distinguish dependent individuals from those at risk of dependence. Variables on health status, social support, and lifestyles were considered. RESULTS We found that 18.6% of the population presented a risk of dependence, especially after age 65. Compared with this group, individuals who reported dependence (11.0%) had difficulties performing activities of daily living and had to receive support to perform them. Habits such as smoking, excessive alcohol consumption, and being sedentary were associated with a higher probability of dependence, particularly for women. CONCLUSIONS Difficulties in carrying out activities of daily living precede the onset of dependence. Preserving personal autonomy and function without receiving support appear to be a preventive factor. Adopting an active and healthy lifestyle helps reduce the risk of dependence. PMID:26018786
Risk of dependence associated with health, social support, and lifestyle.
Alcañiz, Manuela; Brugulat, Pilar; Guillén, Montserrat; Medina-Bustos, Antonia; Mompart-Penina, Anna; Solé-Auró, Aïda
2015-01-01
OBJECTIVE To analyze the prevalence of individuals at risk of dependence and its associated factors. METHODS The study was based on data from the Catalan Health Survey, Spain conducted in 2010 and 2011. Logistic regression models from a random sample of 3,842 individuals aged ≥ 15 years were used to classify individuals according to the state of their personal autonomy. Predictive models were proposed to identify indicators that helped distinguish dependent individuals from those at risk of dependence. Variables on health status, social support, and lifestyles were considered. RESULTS We found that 18.6% of the population presented a risk of dependence, especially after age 65. Compared with this group, individuals who reported dependence (11.0%) had difficulties performing activities of daily living and had to receive support to perform them. Habits such as smoking, excessive alcohol consumption, and being sedentary were associated with a higher probability of dependence, particularly for women. CONCLUSIONS Difficulties in carrying out activities of daily living precede the onset of dependence. Preserving personal autonomy and function without receiving support appear to be a preventive factor. Adopting an active and healthy lifestyle helps reduce the risk of dependence.
Cunha, Liliana; Nogueira, Sónia; Lacomblez, Marianne
2014-01-01
Bus driving is a typically male occupation undergoing a process of feminization. Although men remain a majority, women's integration has raised some questions, namely, related to work organization or its impact on health. This paper focuses on the contributions of assuming a gender perspective in the analysis of the bus driving occupation and the conditions under which it is performed. Twenty female and 158 male bus drivers. Qualitative and quantitative approaches were combined. Ergonomic work analysis and individual interviews were used, as well as INSAT (Work and Health Questionnaire). Difficulties inherent to the work activity were highlighted, in terms of working hours and management of "peripheral tasks", with implications for the balance between professional and personal life. These difficulties were reported differently by men and women, although both made themselves clear about the impact on their career and health. Taking gender into consideration has enabled an enrichment of the questions that guide the analysis of this work activity, and contributed to a new perspective on the work performed by this occupational group as well as a new approach to study the history of the transport industry by proposing as focus of analysis issues related to "gender mobility".
Effect of feedback mode and task difficulty on quality of timing decisions in a zero-sum game.
Tikuisis, Peter; Vartanian, Oshin; Mandel, David R
2014-09-01
The objective was to investigate the interaction between the mode of performance outcome feedback and task difficulty on timing decisions (i.e., when to act). Feedback is widely acknowledged to affect task performance. However, the extent to which feedback display mode and its impact on timing decisions is moderated by task difficulty remains largely unknown. Participants repeatedly engaged a zero-sum game involving silent duels with a computerized opponent and were given visual performance feedback after each engagement. They were sequentially tested on three different levels of task difficulty (low, intermediate, and high) in counterbalanced order. Half received relatively simple "inside view" binary outcome feedback, and the other half received complex "outside view" hit rate probability feedback. The key dependent variables were response time (i.e., time taken to make a decision) and survival outcome. When task difficulty was low to moderate, participants were more likely to learn and perform better from hit rate probability feedback than binary outcome feedback. However, better performance with hit rate feedback exacted a higher cognitive cost manifested by higher decision response time. The beneficial effect of hit rate probability feedback on timing decisions is partially moderated by task difficulty. Performance feedback mode should be judiciously chosen in relation to task difficulty for optimal performance in tasks involving timing decisions.
Alústiza, Irene; Radua, Joaquim; Albajes-Eizagirre, Anton; Domínguez, Manuel; Aubá, Enrique; Ortuño, Felipe
2016-01-01
Timing and other cognitive processes demanding cognitive control become interlinked when there is an increase in the level of difficulty or effort required. Both functions are interrelated and share neuroanatomical bases. A previous meta-analysis of neuroimaging studies found that people with schizophrenia had significantly lower activation, relative to normal controls, of most right hemisphere regions of the time circuit. This finding suggests that a pattern of disconnectivity of this circuit, particularly in the supplementary motor area, is a trait of this mental disease. We hypothesize that a dysfunctional temporal/cognitive control network underlies both cognitive and psychiatric symptoms of schizophrenia and that timing dysfunction is at the root of the cognitive deficits observed. The goal of our study was to look, in schizophrenia patients, for brain structures activated both by execution of cognitive tasks requiring increased effort and by performance of time perception tasks. We conducted a signed differential mapping (SDM) meta-analysis of functional neuroimaging studies in schizophrenia patients assessing the brain response to increasing levels of cognitive difficulty. Then, we performed a multimodal meta-analysis to identify common brain regions in the findings of that SDM meta-analysis and our previously-published activation likelihood estimate (ALE) meta-analysis of neuroimaging of time perception in schizophrenia patients. The current study supports the hypothesis that there exists an overlap between neural structures engaged by both timing tasks and non-temporal cognitive tasks of escalating difficulty in schizophrenia. The implication is that a deficit in timing can be considered as a trait marker of the schizophrenia cognitive profile. PMID:26925013
Yang, Hsiang-Yu; Sanford, Jon A.
2012-01-01
This paper describes relationships among home and community environmental features, activity performance in the home, and community participation potential to support aging in place. A subset of data on older adults with functional limitations (N = 122), sixty three (63) with mobility and 59 with other limitations, were utilized in this study from a larger project's subject pool. Results showed significant and positive correlations between environmental barriers, activity dependence and difficulty at home, and less community participation in the mobility limitation group. While kitchen and bathroom features were most limiting to home performance, bathtub or shower was the only home feature, and destination social environment was the only community feature, that explained community participation. Compared to environmental features, home performance explained much more community participation. Study results provide detailed information about environmental features as well as types of home activities that can be prioritized as interventions for aging in place. PMID:22162808
Brown, Jamie C; Goldstein, Judith E; Chan, Tiffany L; Massof, Robert; Ramulu, Pradeep
2014-08-01
To characterize functional complaints of new low-vision rehabilitation patients. Prospective observational study. The Low Vision Rehabilitation Outcomes Study recruited 819 patients between 2008 and 2011 from 28 clinical centers in the United States. New patients referred for low-vision rehabilitation were asked, "What are your chief complaints about your vision?" before their appointment. Full patient statements were transcribed as free text. Two methods assessed whether statements indicated difficulty in each of 13 functional categories: (1) assessment by 2 masked clinicians reading the statement, and (2) a computerized search of the text for specific words or word fragments. Logistic regression models were used to predict the influence of age, gender, and visual acuity on the likelihood of reporting a complaint in each functional category. Prevalence and risk factors for patient concerns within various functional categories. Reading was the most common functional complaint (66.4% of patients). Other functional difficulties expressed by at least 10% of patients included driving (27.8%), using visual assistive equipment (17.5%), mobility (16.3%), performing in-home activities (15.1%), lighting and glare (11.7%), and facial recognition and social interactions (10.3%). Good agreement was noted between the masked clinician graders and the computerized algorithm for categorization of functional complaints (median κ of 0.84 across the 13 categories). Multivariate logistic regression models demonstrated that the likelihood of reading difficulties increased mildly with age (odds ratio, 1.4 per 10-year increment in age; 95% confidence interval, 1.3-1.6), but did not differ with visual acuity (P = 0.09). Additionally, men were more likely to report driving difficulties and difficulties related to lighting, whereas women were more likely to report difficulty with either in-home activities or facial recognition or social interaction (P<0.05 for all). Mobility concerns, defined as walking difficulty and out-of-home activities, showed no relationship to gender, age, or visual acuity. Reading was the most commonly reported difficulty, regardless of the patient's diagnosis. Neither visual acuity nor gender were predictive of reading concerns, although, age showed a small effect. Addressing reading rehabilitation should be a cornerstone of low-vision therapy. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
Basso Moro, Sara; Bisconti, Silvia; Muthalib, Makii; Spezialetti, Matteo; Cutini, Simone; Ferrari, Marco; Placidi, Giuseppe; Quaresima, Valentina
2014-01-15
Previous functional near-infrared spectroscopy (fNIRS) studies indicated that the prefrontal cortex (PFC) is involved in the maintenance of the postural balance after external perturbations. So far, no studies have been conducted to investigate the PFC hemodynamic response to virtual reality (VR) tasks that could be adopted in the field of functional neurorehabilitation. The aim of this fNIRS study was to assess PFC oxygenation response during an incremental and a control swing balance task (ISBT and CSBT, respectively) in a semi-immersive VR environment driven by a depth-sensing camera. It was hypothesized that: i) the PFC would be bilaterally activated in response to the increase of the ISBT difficulty, as this cortical region is involved in the allocation of attentional resources to maintain postural control; and ii) the PFC activation would be greater in the right than in the left hemisphere considering its dominance for visual control of body balance. To verify these hypotheses, 16 healthy male subjects were requested to stand barefoot while watching a 3 dimensional virtual representation of themselves projected onto a screen. They were asked to maintain their equilibrium on a virtual blue swing board susceptible to external destabilizing perturbations (i.e., randomizing the forward-backward direction of the impressed pulse force) during a 3-min ISBT (performed at four levels of difficulty) or during a 3-min CSBT (performed constantly at the lowest level of difficulty of the ISBT). The center of mass (COM), at each frame, was calculated and projected on the floor. When the subjects were unable to maintain the COM over the board, this became red (error). After each error, the time required to bring back the COM on the board was calculated (returning time). An eight-channel continuous wave fNIRS system was employed for measuring oxygenation changes (oxygenated-hemoglobin, O2Hb; deoxygenated-hemoglobin, HHb) related to the PFC activation (Brodmann Areas 10, 11 and 46). The results have indicated that the errors increased between the first and the second level of difficulty of the ISBT, then decreased and remained constant; the returning time progressively increased during the first three levels of difficulty and then remained constant. During the CSBT, the errors and the returning time did not change. In the ISBT, the increase of the first three levels of difficulty was accompanied by a progressive increase in PFC O2Hb and a less consistent decrease in HHb. A tendency to plateau was observable for PFC O2Hb and HHb changes in the fourth level of difficulty of the ISBT, which could be partly explained by a learning effect. A right hemispheric lateralization was not found. A lower amplitude of increase in O2Hb and decrease in HHb was found in the PFC in response to the CSBT with respect to the ISBT. This study has demonstrated that the oxygenation increased over the PFC while performing an ISBT in a semi-immersive VR environment. These data reinforce the involvement of the PFC in attention-demanding balance tasks. Considering the adaptability of this virtual balance task to specific neurological disorders, the absence of motion sensing devices, and the motivating/safe semi-immersive VR environment, the ISBT adopted in this study could be considered valuable for diagnostic testing and for assessing the effectiveness of functional neurorehabilitation. Copyright © 2013 Elsevier Inc. All rights reserved.
Kimble, L P
2001-01-01
Household tasks are highly salient physical activities for women. Inability to perform household tasks may serve as an important marker of limitations imposed by cardiac symptoms. The purpose of this study was to examine the impact of cardiac symptoms on perceived ability to perform household tasks in women with coronary artery disease and to examine relationships among age, whether the woman lived alone, ability to perform household tasks, and cardiac-related quality of life. Forty-one women with confirmed diagnosis of coronary artery disease and a mean age of 66 years (SD 12 years) were interviewed about the impact of their cardiac symptoms and perceived ability to perform household tasks (Household Activities Scale) and cardiac-related quality of life (Seattle Angina Questionnaire). The women were primarily white (89.4%) and retired (65.9%). Forty-six percent were married, and 26.8% lived alone. "Washing dishes" (51.3%) was the only task a majority of the sample could perform without limitation. Household tasks most commonly reported as no longer performed included carrying laundry (24.4%), vacuuming (30.0%), and scrubbing the floor (51.2%). The task most commonly modified because of cardiac symptoms was changing bed linens (60%). Of the 14 household tasks, women performed a mean of 3.39 (SD 3.36) activities without difficulty. Total number of household activities performed without difficulty was associated with better quality of life in the area of exertional capacity (r = 0.50, P = 0.001). Women who lived alone reported greater perceived ability to perform household tasks than women who did not live alone (r = 0.31, P = 0.05). Age was not significantly associated with perceived household task performance (r = -0.22, P = 0.17). Women with coronary artery disease (CAD) perceived cardiac symptoms as disrupting their ability to perform household tasks. Future research is needed to determine the independent impact of cardiac symptoms on functional limitations, especially in older women with heart disease, and whether changes in ability to perform household tasks could be a marker for coronary artery disease progression in women.
Li, Kin-Kit; Cardinal, Bradley J; Vuchinich, Samuel
2009-03-01
This study examined the effect of health worry (i.e., cognitive aspect of anxiety resulting from concern for health) on walking difficulty in a nationally representative sample (N = 7,527) of older adults (M age = 76.83 years). The study further tested whether physical activity mediates the effect of health worry on walking difficulty in a 6-year follow-up design. Results of a mediation analysis using structural equation modeling showed that people with a high degree of health worry engaged in less physical activity (beta = -.24, p < .001), and people who participated in less physical activity were more likely to report walking difficulty at the 6-year follow-up (beta = -.22, p < .001). There was a significant indirect effect from health worry to walking difficulty through physical activity (beta = .05, p < .001), controlling for demographic, psychosocial, and health related factors. Results suggested that inducing threat and worry may not be effective for physical activity promotion in the older population. More promising coping and regulation strategies are discussed.
Ventral and Dorsal Visual Stream Contributions to the Perception of Object Shape and Object Location
Zachariou, Valentinos; Klatzky, Roberta; Behrmann, Marlene
2017-01-01
Growing evidence suggests that the functional specialization of the two cortical visual pathways may not be as distinct as originally proposed. Here, we explore possible contributions of the dorsal “where/how” visual stream to shape perception and, conversely, contributions of the ventral “what” visual stream to location perception in human adults. Participants performed a shape detection task and a location detection task while undergoing fMRI. For shape detection, comparable BOLD activation in the ventral and dorsal visual streams was observed, and the magnitude of this activation was correlated with behavioral performance. For location detection, cortical activation was significantly stronger in the dorsal than ventral visual pathway and did not correlate with the behavioral outcome. This asymmetry in cortical profile across tasks is particularly noteworthy given that the visual input was identical and that the tasks were matched for difficulty in performance. We confirmed the asymmetry in a subsequent psychophysical experiment in which participants detected changes in either object location or shape, while ignoring the other, task-irrelevant dimension. Detection of a location change was slowed by an irrelevant shape change matched for difficulty, but the reverse did not hold. We conclude that both ventral and dorsal visual streams contribute to shape perception, but that location processing appears to be essentially a function of the dorsal visual pathway. PMID:24001005
Frontal theta activation during motor synchronization in autism.
Kawasaki, Masahiro; Kitajo, Keiichi; Fukao, Kenjiro; Murai, Toshiya; Yamaguchi, Yoko; Funabiki, Yasuko
2017-11-08
Autism is characterized by two primary characteristics: deficits in social interaction and repetitive behavioral patterns. Because interpersonal communication is extremely complicated, its underlying brain mechanisms remain unclear. Here we showed that both characteristics can be explained by a unifying underlying mechanism related to difficulties with irregularities. To address the issues, we measured electroencephalographm during a cooperative tapping task, which required participants to tap a key alternately and synchronously with constant rhythmic a PC program, a variable rhythmic PC program, or a human partner. We found that people with autism had great difficulty synchronizing tapping behavior with others, and exhibited greater than normal theta-wave (6 Hz) activity in the frontal cortex during the task, especially when their partner behaved somewhat irregularly (i.e. a variable rhythmic PC program or a human partner). Importantly, the higher theta-wave activity was related to the severity of autism, not the performance on the task. This indicates that people with autism need to use intense cognition when trying to adapt to irregular behavior and can easily become overtaxed. Difficulty adapting to irregular behavior in others is likely related to their own tendencies for repetitive and regular behaviors. Thus, while the two characteristics of autism have been comprehended separately, our unifying theory makes understanding the condition and developing therapeutic strategies more tractable.
Wilson, Glenn F; Russell, Christopher A
The functional state of the human operator is critical to optimal system performance. Degraded states of operator functioning can lead to errors and overall suboptimal system performance. Accurate assessment of operator functional state is crucial to the successful implementation of an adaptive aiding system. One method of determining operators' functional state is by monitoring their physiology. In the present study, artificial neural networks using physiological signals were used to continuously monitor, in real time, the functional state of 7 participants while they performed the Multi-Attribute Task Battery with two levels of task difficulty. Six channels of brain electrical activity and eye, heart and respiration measures were evaluated on line. The accuracy of the classifier was determined to test its utility as an on-line measure of operator state. The mean classification accuracies were 85%, 82%, and 86% for the baseline, low task difficulty, and high task difficulty conditions, respectively. The high levels of accuracy suggest that these procedures can be used to provide accurate estimates of operator functional state that can be used to provide adaptive aiding. The relative contribution of each of the 43 psychophysiological features was also determined. Actual or potential applications of this research include test and evaluation and adaptive aiding implementation.
Akizuki, Kazunori; Ohashi, Yukari
2015-10-01
The relationship between task difficulty and learning benefit was examined, as was the measurability of task difficulty. Participants were required to learn a postural control task on an unstable surface at one of four different task difficulty levels. Results from the retention test showed an inverted-U relationship between task difficulty during acquisition and motor learning. The second-highest level of task difficulty was the most effective for motor learning, while learning was delayed at the most and least difficult levels. Additionally, the results indicate that salivary α-amylase and the performance dimension of the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) are useful indices of task difficulty. Our findings suggested that instructors may be able to adjust task difficulty based on salivary α-amylase and the performance dimension of the NASA-TLX to enhance learning. Copyright © 2015 Elsevier B.V. All rights reserved.
Summarizing the Effect of a Wide Array of Amenity Measures into Simple Components
ERIC Educational Resources Information Center
Gunderson, Ronald J.; Ng, Pin T.
2006-01-01
A significant issue existing within the rural economic development literature revolves around the difficulty with sorting out the controversy of the effects of amenity activities on rural economic growth. This problem is due to the different ways amenity attributes are linked to regional economic performance. Numerous researchers utilize principal…
ERIC Educational Resources Information Center
Proffitt-White, Rob
2017-01-01
The Teachers First initiative is a grass-roots cluster-model approach for bringing together primary and secondary teachers and school principals: to analyse student performance data; design and practice activities and assessment tools; and promote teaching practices that address students' learning difficulties in mathematics. The balance of both…
Hardware demonstration of flexible beam control
NASA Technical Reports Server (NTRS)
Schaechter, D. B.
1980-01-01
An experiment employing a pinned-free flexible beam has been constructed to demonstrate and verify several facets of the control of flexible structures. The desired features of the experiment are to demonstrate active shape control, active dynamic control, adaptive control, various control law design approaches, and associated hardware requirements and mechanization difficulties. This paper contains the analytical work performed in support of the facility development, the final design specifications, control law synthesis, and some preliminary results.
TASKILLAN II - Pilot strategies for workload management
NASA Technical Reports Server (NTRS)
Segal, Leon D.; Wickens, Christopher D.
1990-01-01
This study focused on the strategies used by pilots in managing their workload level, and their subsequent task performance. Sixteen licensed pilots flew 42 missions on a helicopter simulation, and were evaluated on their performance of the overall mission, as well as individual tasks. Pilots were divided in four groups, defined by the presence or absence of scheduling control over tasks and the availability of intelligence concerning the type and stage of difficulties imposed during the flight. Results suggest that intelligence supported strategies that yielded significant higher performance levels, while scheduling control seemed to have no impact on performance. Both difficulty type and the stage of difficulty impacted performance significantly, with strongest effects for time stresss and difficulties imposed late in the flight.
Angel, Lucie; Bastin, Christine; Genon, Sarah; Salmon, Eric; Fay, Séverine; Balteau, Evelyne; Maquet, Pierre; Luxen, André; Isingrini, Michel; Collette, Fabienne
2016-01-15
The current experiment aimed to explore age differences in brain activity associated with successful memory retrieval in older adults with different levels of executive functioning, at different levels of task demand. Memory performance and fMRI activity during a recognition task were compared between a young group and two older groups characterized by a low (old-low group) vs. high (old-high group) level of executive functioning. Participants first encoded pictures, presented once (Hard condition) or twice (Easy condition), and then completed a recognition memory task. Old-low adults had poorer memory performance than the two other groups, which did not differ, in both levels of task demands. In the Easy condition, even though older adults demonstrated reduced activity compared to young adults in several regions, they also showed additional activations in the right superior frontal gyrus and right parietal lobule (positively correlated to memory accuracy) for the old-high group and in the right precuneus (negatively correlated to memory accuracy), right anterior cingulate gyrus and right supramarginal gyrus for the old-low group. In the Hard condition, some regions were also more activated in the young group than in the older groups. Vice versa, old-high participants demonstrated more activity than either the young or the old-low group in the right frontal gyrus, associated with more accurate memory performance, and in the left frontal gyrus. In sum, the present study clearly showed that age differences in the neural correlates of retrieval success were modulated by task difficulty, as suggested by the CRUNCH model, but also by interindividual variability, in particular regarding executive functioning. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Sergievskii, V. V.; Rudakov, A. M.
2006-11-01
An analysis of the accepted methods for calculating the activity coefficients for the components of binary aqueous solutions was performed. It was demonstrated that the use of the osmotic coefficients in auxiliary calculations decreases the accuracy of estimates of the activity coefficients. The possibility of calculating the activity coefficient of the solute from the concentration dependence of the water activity was examined. It was established that, for weak electrolytes, the interpretation of data on heterogeneous equilibria within the framework of the standard assumption that the dissociation is complete encounters serious difficulties.
Nielsen, Mie Marie; Maribo, Thomas; Westergren, Albert; Melgaard, Dorte
2018-06-01
Eating difficulties, having a poor nutritional status, and low activity of daily living are all prevalent issues in the geriatric population. The aim of this study was to explore associations between patients' eating difficulties, their nutritional status and their activity of daily living in patients aged 60 years or older who were admitted to an acute geriatric unit. A cross-sectional study was conducted between March and September 2016 at the geriatric department of North Denmark Regional Hospital, Hjørring. The inclusion criteria were: ≥ 60years old and hospitalized for a minimum of 24 h. The patients' eating difficulties were assessed using the Minimal Eating Observational Form (MEOF-II), including observations related to ingestion, deglutition and energy/appetite. Eating difficulties were determined on the basis of one or more components of the MEOF-II. Poor nutritional status was defined as an age-specific low body mass index (BMI), <20 kg/m 2 if < 70 years, or <22 kg/m 2 if ≥ 70 years. Activity of daily living was assessed using the Barthel-100 Index and defined as low (<50) or high (≥50). A total of 297 geriatric patients were included; the mean age was 83.0 (7.7) years and 56.2% of the patients were female. The prevalence of eating difficulties was 55%. Geriatric patients with eating difficulties had a risk increase of 155% of having poor nutritional status (p = 0.003). Geriatric patients with eating difficulties had a risk increase of 60% of having low activity of daily living (p < 0.001). Eating difficulties were highly prevalent in geriatric patients and were associated with poor nutritional status and reduced activity of daily living. The identification of eating difficulties may be important for nutritional interventions and maintenance or improvement of activities of daily living in the geriatric population. Copyright © 2018 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.
Understanding handwriting difficulties: A comparison of children with and without motor impairment.
Prunty, Mellissa; Barnett, Anna L
The nature of handwriting difficulties have been explored in children with specific developmental disorders. The aim of this study was to investigate the nature of handwriting difficulties in children with dysgraphia, a less studied group who have significant handwriting difficulties in the absence of motor control or cognitive difficulties. The performance of a dysgraphia group aged 8-14 years was compared to a group with Developmental Coordination Disorder and to typically developing (TD) controls. Participants completed two handwriting tasks on a digitizing writing tablet. The amount and accuracy of the handwriting product was measured, plus various temporal and spatial features of the writing process. There were no significant differences in performance between the two groups with handwriting difficulties but both performed more poorly than the TD group. Individual differences in the type and severity of handwriting impairments suggest the need for a range of classroom assessments to tailor intervention appropriately.
Object-location memory in adults with autism spectrum disorder.
Ring, Melanie; Gaigg, Sebastian B; Bowler, Dermot M
2015-10-01
This study tested implicit and explicit spatial relational memory in Autism Spectrum Disorder (ASD). Participants were asked to study pictures of rooms and pictures of daily objects for which locations were highlighted in the rooms. Participants were later tested for their memory of the object locations either by being asked to place objects back into their original locations or into new locations. Proportions of times when participants choose the previously studied locations for the objects irrespective of the instruction were used to derive indices of explicit and implicit memory [process-dissociation procedure, Jacoby, 1991, 1998]. In addition, participants performed object and location recognition and source memory tasks where they were asked about which locations belonged to the objects and which objects to the locations. The data revealed difficulty for ASD individuals in actively retrieving object locations (explicit memory) but not in subconsciously remembering them (implicit memory). These difficulties cannot be explained by difficulties in memory for objects or locations per se (i.e., the difficulty pertains to object-location relations). Together these observations lend further support to the idea that ASD is characterised by relatively circumscribed difficulties in relational rather than item-specific memory processes and show that these difficulties extend to the domain of spatial information. They also lend further support to the idea that memory difficulties in ASD can be reduced when support is provided at test. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.
[Marketing in health service].
Ameri, Cinzia; Fiorini, Fulvio
2014-01-01
The gradual emergence of marketing activities in public health demonstrates an increased interest in this discipline, despite the lack of an adequate and universally recognized theoretical model. For a correct approach to marketing techniques, it is opportune to start from the health service, meant as a service rendered. This leads to the need to analyse the salient features of the services. The former is the intangibility, or rather the ex ante difficulty of making the patient understand the true nature of the performance carried out by the health care worker. Another characteristic of all the services is the extreme importance of the regulator, which means who performs the service (in our case, the health care professional). Indeed the operator is of crucial importance in health care: being one of the key issues, he becomes a part of the service itself. Each service is different because the people who deliver it are different, furthermore there are many variables that can affect the performance. Hence it arises the difficulty in measuring the services quality as well as in establishing reference standards.
Frith, James; Day, Christopher P; Robinson, Lisa; Elliott, Chris; Jones, David E J; Newton, Julia L
2010-01-01
The management of non-alcoholic liver disease (NAFLD) concerns lifestyle modification and exercise; however, adherence is poor. Factors such as lack of confidence to exercise, poor understanding of the benefits of exercise, and a fear of falling all influence engagement in physical activity. To increase exercise in NAFLD it is important to understand the barriers to performing it. Three chronic liver disease cohorts were identified from the Newcastle Liver Database: NAFLD (n=230), alcoholic liver disease (ALD, n=110) and primary biliary cirrhosis (PBC, n=97). Assessment tools were completed by all subjects: Outcome Expectation for Exercise Scale (OEES, understanding the benefits of exercise, lower scores indicate greater understanding), Self-Efficacy for Exercise Scale (SEES, confidence to exercise), Falls Efficacy Scale-International (FES-I, higher scores indicate greater fear of falling). Activity was analysed from a functional perspective using the PROMIS-HAQ. Understanding the benefits of exercise was similar across each group [median OEES scores: NAFLD 2.38 (range 0.0-5.0), ALD 2.25 (0.0-5.0), PBC 2.28 (1.0-5.0), p=0.6]. In NAFLD confidence to exercise was significantly lower [median SEES score 0.0 (0.0-10.0), PBC 4.5 (0.0-10.0), p<0.001]. Fear of falling was similar in NAFLD and PBC, and greatest in ALD [22 (0-64), 22 (3-64), 30 (0-64), p=0.044]. In NAFLD, fear of falling was independently associated with increasing difficulty performing activity. NAFLD patients understand the benefits of exercise but lack confidence to perform it. Fear of falling was independently associated with more difficulty performing activity. Fear of falling and confidence are modifiable and potential targets to improve uptake and adherence for exercise intervention.
A Novel Method for Assessing Task Complexity in Outpatient Clinical-Performance Measures.
Hysong, Sylvia J; Amspoker, Amber B; Petersen, Laura A
2016-04-01
Clinical-performance measurement has helped improve the quality of health-care; yet success in attaining high levels of quality across multiple domains simultaneously still varies considerably. Although many sources of variability in care quality have been studied, the difficulty required to complete the clinical work itself has received little attention. We present a task-based methodology for evaluating the difficulty of clinical-performance measures (CPMs) by assessing the complexity of their component requisite tasks. Using Functional Job Analysis (FJA), subject-matter experts (SMEs) generated task lists for 17 CPMs; task lists were rated on ten dimensions of complexity, and then aggregated into difficulty composites. Eleven outpatient work SMEs; 133 VA Medical Centers nationwide. Clinical Performance: 17 outpatient CPMs (2000-2008) at 133 VA Medical Centers nationwide. Measure Difficulty: for each CPM, the number of component requisite tasks and the average rating across ten FJA complexity scales for the set of tasks comprising the measure. Measures varied considerably in the number of component tasks (M = 10.56, SD = 6.25, min = 5, max = 25). Measures of chronic care following acute myocardial infarction exhibited significantly higher measure difficulty ratings compared to diabetes or screening measures, but not to immunization measures ([Formula: see text] = 0.45, -0.04, -0.05, and -0.06 respectively; F (3, 186) = 3.57, p = 0.015). Measure difficulty ratings were not significantly correlated with the number of component tasks (r = -0.30, p = 0.23). Evaluating the difficulty of achieving recommended CPM performance levels requires more than simply counting the tasks involved; using FJA to assess the complexity of CPMs' component tasks presents an alternate means of assessing the difficulty of primary-care CPMs and accounting for performance variation among measures and performers. This in turn could be used in designing performance reward programs, or to match workflow to clinician time and effort.
Meulemans, J; Goeleven, A; Zink, I; Loyez, L; Lagae, L; Debruyne, F
2012-01-01
We investigated the relationship between possible underlying neurological dysfunction and a significant discrepancy between verbal IQ/performance IQ (VIQ-PIQ) in children with language, speech or learning difficulties. In a retrospective study, we analysed data obtained from intelligence testing and neurological evaluation in 49 children with a significant VIQ-PIQ discrepancy (> or = 25 points) who were referred because of language, speech or learning difficulties to the Multidisciplinary University Centre for Logopedics and Audiology (MUCLA) of the University Hospitals of Leuven, Belgium. The group of children broke down into a group of 35 children with PIQ > VIQ and a group of 14 children with VIQ > PIQ. In the first group, neurological data were present for 24 children. The neurological history and clinical neurological examination were normal in all cases. Brain MRI was performed in 15 cases and proved to be normal in all children. Brain activity was assessed with long-term video EEG monitoring in ten children. In two children, the EEG results were abnormal: there was an epileptic focus in one child and a manifest alteration in the EEG typical of Landau-Kleffner syndrome in the other. In the second group of 14 children whose VIQ was higher than the PIQ, neurological data were available for ten children. Neurological history and clinical neurological examination were normal in all cases. Brain MRI was performed in five cases and was normal in all children. EEG monitoring was performed in one child. This revealed benign childhood epilepsy with centrotemporal spikes. In a small number of children (9%) with speech, language and learning difficulties and a discrepancy between VIQ and PIQ, an underlying neurological abnormality is present. We recommend referring children with a significant VIQ-PIQ mismatch to a paediatric neurologist. As an epileptic disorder seems to be the most common underlying neurological pathology in this specific group of children, EEG monitoring should be recommended in these children. Neuro-imaging should only be used in selected patients.
2011-01-01
Background Current guidelines for rehabilitation of arm and hand function after stroke recommend that motor training focus on realistic tasks that require reaching and manipulation and engage the patient intensively, actively, and adaptively. Here, we investigated the feasibility of a novel robotic task-practice system, ADAPT, designed in accordance with such guidelines. At each trial, ADAPT selects a functional task according to a training schedule and with difficulty based on previous performance. Once the task is selected, the robot picks up and presents the corresponding tool, simulates the dynamics of the tasks, and the patient interacts with the tool to perform the task. Methods Five participants with chronic stroke with mild to moderate impairments (> 9 months post-stroke; Fugl-Meyer arm score 49.2 ± 5.6) practiced four functional tasks (selected out of six in a pre-test) with ADAPT for about one and half hour and 144 trials in a pseudo-random schedule of 3-trial blocks per task. Results No adverse events occurred and ADAPT successfully presented the six functional tasks without human intervention for a total of 900 trials. Qualitative analysis of trajectories showed that ADAPT simulated the desired task dynamics adequately, and participants reported good, although not excellent, task fidelity. During training, the adaptive difficulty algorithm progressively increased task difficulty leading towards an optimal challenge point based on performance; difficulty was then continuously adjusted to keep performance around the challenge point. Furthermore, the time to complete all trained tasks decreased significantly from pretest to one-hour post-test. Finally, post-training questionnaires demonstrated positive patient acceptance of ADAPT. Conclusions ADAPT successfully provided adaptive progressive training for multiple functional tasks based on participant's performance. Our encouraging results establish the feasibility of ADAPT; its efficacy will next be tested in a clinical trial. PMID:21813010
Applicability Evaluation of Job Standards for Diabetes Nutritional Management by Clinical Dietitian
2017-01-01
This study was conducted to evaluate applicability of job standards for diabetes nutrition management by hospital clinical dietitians. In order to promote the clinical nutrition services, it is necessary to present job standards of clinical dietitian and to actively apply these standardized tasks to the medical institution sites. The job standard of clinical dietitians for diabetic nutrition management was distributed to hospitals over 300 beds. Questionnaire was collected from 96 clinical dietitians of 40 tertiary hospitals, 47 general hospitals, and 9 hospitals. Based on each 5-point scale, the importance of overall duty was 4.4 ± 0.5, performance was 3.6 ± 0.8, and difficulty was 3.1 ± 0.7. ‘Nutrition intervention’ was 4.5 ± 0.5 for task importance, ‘nutrition assessment’ was 4.0 ± 0.7 for performance, and ‘nutrition diagnosis’ was 3.4 ± 0.9 for difficulty. These 3 items were high in each category. Based on the grid diagram, the tasks of both high importance and high performance were ‘checking basic information,’ ‘checking medical history and therapy plan,’ ‘decision of nutritional needs,’ ‘supply of foods and nutrients,’ and ‘education of nutrition and self-management.’ The tasks with high importance but low performance were ‘derivation of nutrition diagnosis,’ ‘planning of nutrition intervention,’ ‘monitoring of nutrition intervention process.’ The tasks of both high importance and high difficulty were ‘derivation of nutrition diagnosis,’ ‘planning of nutrition intervention,’ ‘supply of foods and nutrients,’ ‘education of nutrition and self-management,’ and ‘monitoring of nutrition intervention process.’ The tasks of both high performance and high difficulty were ‘documentation of nutrition assessment,’ ‘supply of foods and nutrients,’ and ‘education of nutrition and self-management.’ PMID:28503506
Psychological distress, television viewing, and physical activity in children aged 4 to 12 years.
Hamer, Mark; Stamatakis, Emmanuel; Mishra, Gita
2009-05-01
Sedentary behavior and physical activity may be independent risk factors for psychological distress in adolescents, although there is no existing information for children. We examined the cross-sectional association between psychological distress, television and screen entertainment time, and physical activity levels among a representative sample of children aged 4 to 12 years from the 2003 Scottish Health Survey. Participants were 1486 boys and girls (mean age: 8.5 +/- 2.3 years). Parents answered on behalf of children who were required to be present. The parents completed the Strengths and Difficulties Questionnaire and information on television and screen entertainment time, physical activity, and dietary intake of their children. An abnormally high Strengths and Difficulties Questionnaire total difficulties score (20-40) was found in 4.2% of the sample. Approximately 25% of the children were exposed to television and screen entertainment at least 3 hours/day. In general linear models, television and screen entertainment time per week and physical activity levels were independently associated with the Strengths and Difficulties Questionnaire total difficulties score after adjustment for age, gender, area deprivation level, single-parent status, medical conditions, and various dietary intake indicators. There was also an additive interaction effect showing that the combination of high television and screen entertainment time and low physical activity was associated with the highest Strengths and Difficulties Questionnaire score. Higher television and screen entertainment exposure (>2.7 hours/day) alone resulted in a 24% increase in the Strengths and Difficulties Questionnaire score in comparison with lower television and screen entertainment exposure (<1.6 hours/day), although when combined with low physical activity this resulted in a 46% increase. Higher levels of television and screen entertainment time and low physical activity levels interact to increase psychological distress in young children.
Modulation of the semantic system by word imageability.
Sabsevitz, D S; Medler, D A; Seidenberg, M; Binder, J R
2005-08-01
A prevailing neurobiological theory of semantic memory proposes that part of our knowledge about concrete, highly imageable concepts is stored in the form of sensory-motor representations. While this theory predicts differential activation of the semantic system by concrete and abstract words, previous functional imaging studies employing this contrast have provided relatively little supporting evidence. We acquired event-related functional magnetic resonance imaging (fMRI) data while participants performed a semantic similarity judgment task on a large number of concrete and abstract noun triads. Task difficulty was manipulated by varying the degree to which the words in the triad were similar in meaning. Concrete nouns, relative to abstract nouns, produced greater activation in a bilateral network of multimodal and heteromodal association areas, including ventral and medial temporal, posterior-inferior parietal, dorsal prefrontal, and posterior cingulate cortex. In contrast, abstract nouns produced greater activation almost exclusively in the left hemisphere in superior temporal and inferior frontal cortex. Increasing task difficulty modulated activation mainly in attention, working memory, and response monitoring systems, with almost no effect on areas that were modulated by imageability. These data provide critical support for the hypothesis that concrete, imageable concepts activate perceptually based representations not available to abstract concepts. In contrast, processing abstract concepts makes greater demands on left perisylvian phonological and lexical retrieval systems. The findings are compatible with dual coding theory and less consistent with single-code models of conceptual representation. The lack of overlap between imageability and task difficulty effects suggests that once the neural representation of a concept is activated, further maintenance and manipulation of that information in working memory does not further increase neural activation in the conceptual store.
Brain Interaction during Cooperation: Evaluating Local Properties of Multiple-Brain Network.
Sciaraffa, Nicolina; Borghini, Gianluca; Aricò, Pietro; Di Flumeri, Gianluca; Colosimo, Alfredo; Bezerianos, Anastasios; Thakor, Nitish V; Babiloni, Fabio
2017-07-21
Subjects' interaction is the core of most human activities. This is the reason why a lack of coordination is often the cause of missing goals, more than individual failure. While there are different subjective and objective measures to assess the level of mental effort required by subjects while facing a situation that is getting harder, that is, mental workload, to define an objective measure based on how and if team members are interacting is not so straightforward. In this study, behavioral, subjective and synchronized electroencephalographic data were collected from couples involved in a cooperative task to describe the relationship between task difficulty and team coordination, in the sense of interaction aimed at cooperatively performing the assignment. Multiple-brain connectivity analysis provided information about the whole interacting system. The results showed that averaged local properties of a brain network were affected by task difficulty. In particular, strength changed significantly with task difficulty and clustering coefficients strongly correlated with the workload itself. In particular, a higher workload corresponded to lower clustering values over the central and parietal brain areas. Such results has been interpreted as less efficient organization of the network when the subjects' activities, due to high workload tendencies, were less coordinated.
Autonomic imbalance is associated with reduced facial recognition in somatoform disorders.
Pollatos, Olga; Herbert, Beate M; Wankner, Sarah; Dietel, Anja; Wachsmuth, Cornelia; Henningsen, Peter; Sack, Martin
2011-10-01
Somatoform disorders are characterized by the presence of multiple somatic symptoms. While the accuracy of perceiving bodily signal (interoceptive awareness) is only sparely investigated in somatoform disorders, recent research has associated autonomic imbalance with cognitive and emotional difficulties in stress-related diseases. This study aimed to investigate how sympathovagal reactivity interacts with performance in recognizing emotions in faces (facial recognition task). Using a facial recognition and appraisal task, skin conductance levels (SCLs), heart rate (HR) and heart rate variability (HRV) were assessed in 26 somatoform patients and compared to healthy controls. Interoceptive awareness was assessed by a heartbeat detection task. We found evidence for a sympathovagal imbalance in somatoform disorders characterized by low parasympathetic reactivity during emotional tasks and increased sympathetic activation during baseline. Somatoform patients exhibited a reduced recognition performance for neutral and sad emotional expressions only. Possible confounding variables such as alexithymia, anxiety or depression were taken into account. Interoceptive awareness was reduced in somatoform patients. Our data demonstrate an imbalance in sympathovagal activation in somatoform disorders associated with decreased parasympathetic activation. This might account for difficulties in processing of sad and neutral facial expressions in somatoform patients which might be a pathogenic mechanism for increased everyday vulnerability. Copyright © 2011 Elsevier Inc. All rights reserved.
Peer Victimization and Depression in Children with and without Motor Coordination Difficulties
ERIC Educational Resources Information Center
Campbell, Wenonah N.; Missiuna, Cheryl; Vaillancourt, Tracy
2012-01-01
Developmental coordination disorder (DCD) is a chronic disability that impacts children's performance of everyday motor-based activities and is associated with the development of secondary social and mental health problems. The purpose of this study was to investigate peer victimization and depression in children who were and were not at risk for…
ERIC Educational Resources Information Center
Kirby, Amanda; Sugden, David; Beveridge, Sally; Edwards, Lisa; Edwards, Rachel
2008-01-01
Developmental co-ordination disorder (DCD) is a developmental disorder affecting motor co-ordination. The "Diagnostics Statistics Manual"--IV classification for DCD describes difficulties across a range of activities of daily living, impacting on everyday skills and academic performance in school. Recent evidence has shown that…
ERIC Educational Resources Information Center
Nakai, Akio; Miyachi, Taishi; Okada, Ryo; Tani, Iori; Nakajima, Shunji; Onishi, Masafumi; Fujita, Chikako; Tsujii, Masatsugu
2011-01-01
Developmental Coordination Disorder (DCD) is characterized by clumsiness and coordination difficulties. DCD interferes with academic performance and participation in physical activities and psychosocial functions, such as self-esteem, cognition, or emotion, from childhood through adolescence to adulthood. DCD is a common pediatric condition and…
Keller, Johannes
2007-06-01
Stereotype threat research revealed that negative stereotypes can disrupt the performance of persons targeted by such stereotypes. This paper contributes to stereotype threat research by providing evidence that domain identification and the difficulty level of test items moderate stereotype threat effects on female students' maths performance. The study was designed to test theoretical ideas derived from stereotype threat theory and assumptions outlined in the Yerkes-Dodson law proposing a nonlinear relationship between arousal, task difficulty and performance. Participants were 108 high school students attending secondary schools. Participants worked on a test comprising maths problems of different difficulty levels. Half of the participants learned that the test had been shown to produce gender differences (stereotype threat). The other half learned that the test had been shown not to produce gender differences (no threat). The degree to which participants identify with the domain of maths was included as a quasi-experimental factor. Maths-identified female students showed performance decrements under conditions of stereotype threat. Moreover, the stereotype threat manipulation had different effects on low and high domain identifiers' performance depending on test item difficulty. On difficult items, low identifiers showed higher performance under threat (vs. no threat) whereas the reverse was true in high identifiers. This interaction effect did not emerge on easy items. Domain identification and test item difficulty are two important factors that need to be considered in the attempt to understand the impact of stereotype threat on performance.
Chang, Kwang-Hwa; Liao, Hua-Fang; Yen, Chia-Fan; Hwang, Ai-Wen; Chi, Wen-Chou; Escorpizo, Reuben; Liou, Tsan-Hon
2015-01-01
To explore the association between muscle power impairment and each World Health Organization Disability Assessment Schedule second edition (WHODAS 2.0) domain score among subjects with physical disability. Subjects (≥ 60 years) with physical disability related to neurological diseases, including 730 subjects with brain disease (BD) and 126 subjects with non-BD, were enrolled from a data bank of persons with disabilities from 1 July 2011 to 29 February 2012. Standardized WHODAS 2.0 scores ranging from 0 (least difficulty) to 100 (greatest difficulty) points were calculated for each domain. More than 50% of subjects with physical disability had the greatest difficulty in household activities and mobility. Muscle power impairment (adjusted odds ratios range among domains, 2.75-376.42, p < 0.001), age (1.38-4.81, p < 0.05), and speech impairment (1.94-5.80, p < 0.05) were associated with BD subjects experiencing the greatest difficulty in most WHODAS 2.0 domains. But a few associated factors were identified for the non-BD group in the study. Although the patterns of difficulty in most daily activities were similar between the BD and non-BD groups, factors associated with the difficulties differed between those two groups. Muscle power impairment, age and speech impairment were important factors associated with difficulties in subjects with BD-related physical disability. Older adults with physical disability often experience difficulties in household activities and mobility. Muscle power impairment is associated with difficulties in daily life in subjects with physical disability related to brain disease. Those subjects with brain disease who had older age, a greater degree of muscle power impairment, and the presence of speech impairment were at higher risk of experiencing difficulties in most daily activities.
Art Therapy with a Child Experiencing Sensory Integration Difficulty. Brief Report
ERIC Educational Resources Information Center
Kearns, Diane
2004-01-01
An increasing number of students diagnosed with difficulties such as attention deficit hyperactivity disorder and Asperger?s syndrome are being seen in schools. Sensory integration difficulties may be part of the symptomatology of these disorders. These difficulties may result in difficulties with both classroom behaviors and academic performance.…
Langenecker, Scott A; Kennedy, Susan E; Guidotti, Leslie M; Briceno, Emily M; Own, Lawrence S; Hooven, Thomas; Young, Elizabeth A; Akil, Huda; Noll, Douglas C; Zubieta, Jon-Kar
2007-12-01
Inhibitory control or regulatory difficulties have been explored in major depressive disorder (MDD) but typically in the context of affectively salient information. Inhibitory control is addressed specifically by using a task devoid of affectively-laden stimuli, to disentangle the effects of altered affect and altered inhibitory processes in MDD. Twenty MDD and 22 control volunteer participants matched by age and gender completed a contextual inhibitory control task, the Parametric Go/No-go (PGNG) task during functional magnetic resonance imaging. The PGNG includes three levels of difficulty, a typical continuous performance task and two progressively more difficult versions including Go/No-go hit and rejection trials. After this test, 15 of 20 MDD patients completed a full 10-week treatment with s-citalopram. There was a significant interaction among response time (control subjects better), hits (control subjects better), and rejections (patients better). The MDD participants had greater activation compared with the control group in frontal and anterior temporal areas during correct rejections (inhibition). Activation during successful inhibitory events in bilateral inferior frontal and left amygdala, insula, and nucleus accumbens and during unsuccessful inhibition (commission errors) in rostral anterior cingulate predicted post-treatment improvement in depression symptoms. The imaging findings suggest that in MDD subjects, greater neural activation in frontal, limbic, and temporal regions during correct rejection of lures is necessary to achieve behavioral performance equivalent to control subjects. Greater activation in similar regions was further predictive of better treatment response in MDD.
Experience gained in operation of the VLF ATD lightning location system
NASA Technical Reports Server (NTRS)
Lee, Anthony C. L.
1991-01-01
The United Kingdom (UK) Meteorological Office's Very Low Frequency (VLF) Arrival Time Difference (ATD) System for long-range location of lightning flashes started automatic international issue of lightning-location products on 17 Jun. 1988. Data from before and after this formal start-date were carefully scrutinized to judge performance. Techniques for estimating location accuracy include internal consistency and comparisons against other systems. Other areas studied were range (up to several thousand km); detection efficiency, saturation effects in active situations, and communication difficulties (for this redundant system); and spurious fix rate. Care was taken to assess the potential of the system, in addition to identifying the operational difficulties of the present implementation.
ERIC Educational Resources Information Center
Sutcliffe, Paul
2006-01-01
This research investigated the frequency discrimination performance of a 6-year-old boy (MH) with language and attentional difficulties. MH had been reported to have literacy problems not paralleling an advanced verbal ability, and he showed difficulties in discriminating non-verbal tones of different frequencies in comparison with children of his…
User surveys support designing a prosthetic wrist that incorporates the Dart Thrower's Motion.
Davidson, Matthew; Bodine, Cathy; Weir, Richard F Ff
2018-03-07
Prosthetic devices are not meeting the needs of people with upper limb amputations. Due to controlsidelimitations, prosthetic wrists cannot yet be fully articulated. This study sought to determine which wrist motions users felt were most important for completing activities of daily living. We specifically invstigated whether adding a combinationof flexion and deviation known as the Dart Thrower's Motion to a prosthetic wrist would help improve functionality. Fifteen participants with a trans-radial amputation, aged 25-64 years, who use a prosthesis completed an online survey and answered interview questions to determine which types of tasks pose particular challenges. Participants were asked what kinds of improvements they would like to see in a new prosthesis. A subset of five participants were interviewed in-depth to provide further information about difficulties they face using their device. The survey showed that participants had difficulty performing activities of daily living that involve a combination of wrist flexion and deviation known as the "Dart Throwers Motion". Interview responses confirmed that users have difficulty performing these tasks, especially those that require tools. Additionally, users said that they were more interested in having flexion and deviation than rotation in a prosthetic wrist. This research indicates that including the Dart Thrower's Motion in future designs of prosthetic wrists would improve these devices and people with upper limb amputations would be excited to see this improvement in their devices. Implications for Rehabilitation • Over one third of people with upper limb amputations do not use a prosthesis because prosthetic devices do not meet their needs.• The number of motions possible in state of the art prosthetic devices is limited by the small number of control sites available.• The Dart Thrower?s Motion is a wrist motion used for many activities of daily living but unavailable in commercial prosthetics leading many prosthetics users to have difficulty with these tasks.• Prosthetic use, and therefore quality of life, could be improved by including the Dart Thrower's Motion in a prosthesis.
The Use of Newspaper Articles as a Tool to Develop Critical Thinking in Science Classes
NASA Astrophysics Data System (ADS)
Oliveras, Begoña; Márquez, Conxita; Sanmartí, Neus
2013-04-01
The aim of this research is to identify the difficulties experienced by secondary school students (aged 15-16) with the critical reading of newspaper articles with scientific content. Two newspaper critical reading activities in relation to the study of various scientific contents were designed and carried out in two schools (61 students in total), one with a student population from a medium to high social and economic bracket and the other with students from a medium to low social and economic bracket. These activities were designed taking into account the phases of the reading process: before, during and after reading. In order to analyse the difficulties 'Elements of science critical reading' were identified on the basis of the 'Elements of reasoning' of Paul and Elder and the categories proposed by Bartz C.R.I.T.I.C. questionnaire and a scale was drawn up. The results show that the activities designed were useful in helping students to read critically. We also rated very positively the instrument created to assess the students' answers: the scale based on the performance indicators of Paul and Elder. This instrument enabled us to detect the aspects of critical thinking where students have the most difficulties: identifying the writer's purpose and looking for evidence in a text. It was also shown that the stance taken in the articles also had an influence on the results.
Quantitative evaluation of distortion in sketching under mono and dual axes whole body vibration.
Bhiwapurkar, M K; Saran, V H; Harsha, S P
2011-01-01
Performance of sedentary activities such as reading and writing, in trains is known to be affected by the vibrations. An experimental study was therefore initiated to investigate the interference perceived in sketching task under low frequency random vibration in both mono and dual axes. Thirty healthy male subjects participated in the study. Random vibration stimuli were excited in various axes in frequency range of 1-20 Hz at magnitudes of 0.4, 0.8 and 1.2 m/s(2). The task required the subjects to sketch the given geometric figures such as circle, rectangle and triangle under vibration environment in two subject postures (sketch pad on lap and on table). Three performance methods were used to measure the effect of vibration stimuli and posture. They consisted of two specifically designed objective methods for percentage distortion measurement and one subjective method using Borg CR10 scale. The results revealed that the percentage distortion and difficulty in sketching increased with an increase in vibration magnitude and was found to be higher for vibration in Y- and Z-axis. Similar trend was observed for percentage distortion and difficulty in sketching for dual axes also. The perceived difficulty and impairment in sketching performance was greater while sketching on lap for X-axis, while the effect was just the reverse for other axes.
Ziebertz, Carla M; van Hooff, Madelon L M; Beckers, Debby G J; Hooftman, Wendela E; Kompier, Michiel A J; Geurts, Sabine A E
2015-01-01
This study examined the relationship between on-call duty exposure (active and total on-call hours a month, number of calls per duty) and employees' experiences of being on-call (stress due to unpredictability, ability to relax during inactive on-call periods, restrictions during on-call duties, on-call work demands, and satisfaction with compensation for on-call duties) on the one hand and fatigue, strain-based and time-based work-home interference (WHI), and perceived on-call performance difficulties (PPD) on the other hand. Cross-sectional survey data were collected among a large heterogeneous sample of Dutch employees (N = 5437). The final sample consisted of 157 on-call workers (23-69 years, 71% males). Data were analyzed by means of hierarchical regression analyses (controlling for age and job characteristics). Differences in on-call work exposure were not systematically related to fatigue, WHI, and PPD (all p's >0.50). The experience of being on-call explained a medium proportion of the variation in fatigue and strain-based WHI and a medium to large proportion of the variation in time-based WHI and PPD over and above the control variables. Our results suggest that it is employees' experience of being on-call, especially the experience of stress due to the unpredictability, rather than the amount of exposure, that is related to fatigue, WHI, and perceived on-call performance difficulties.
Travers, Brittany G; Bigler, Erin D; Duffield, Tyler C; Prigge, Molly D B; Froehlich, Alyson L; Lange, Nicholas; Alexander, Andrew L; Lainhart, Janet E
2017-07-01
Many individuals with autism spectrum disorder (ASD) exhibit motor difficulties, but it is unknown whether manual motor skills improve, plateau, or decline in ASD in the transition from childhood into adulthood. Atypical development of manual motor skills could impact the ability to learn and perform daily activities across the life span. This study examined longitudinal grip strength and finger tapping development in individuals with ASD (n = 90) compared to individuals with typical development (n = 56), ages 5 to 40 years old. We further examined manual motor performance as a possible correlate of current and future daily living skills. The group with ASD demonstrated atypical motor development, characterized by similar performance during childhood but increasingly poorer performance from adolescence into adulthood. Grip strength was correlated with current adaptive daily living skills, and Time 1 grip strength predicted daily living skills eight years into the future. These results suggest that individuals with ASD may experience increasingly more pronounced motor difficulties from adolescence into adulthood and that manual motor performance in ASD is related to adaptive daily living skills. © 2016 John Wiley & Sons Ltd.
Nathan, Liz; Stackhouse, Joy; Goulandris, Nata; Snowling, Margaret J
2004-06-01
Children with speech difficulties may have associated educational problems. This paper reports a study examining the educational attainment of children at Key Stage 1 of the National Curriculum who had previously been identified with a speech difficulty. (1) To examine the educational attainment at Key Stage 1 of children diagnosed with speech difficulties two/three years prior to the present study. (2) To compare the Key Stage 1 assessment results of children whose speech problems had resolved at the time of assessment with those whose problems persisted. Data were available from 39 children who had an earlier diagnosis of speech difficulties at age 4/5 (from an original cohort of 47) at the age of 7. A control group of 35 children identified and matched at preschool on age, nonverbal ability and gender provided comparative data. Results of Statutory Assessment Tests (SATs) in reading, reading comprehension, spelling, writing and maths, administered to children at the end of Year 2 of school were analysed. Performance across the two groups was compared. Performance was also compared to published statistics on national levels of attainment. Children with a history of speech difficulties performed less well than controls on reading, spelling and maths. However, children whose speech problems had resolved by the time of assessment performed no differently to controls. Children with persisting speech problems performed less well than controls on tests of literacy and maths. Spelling performance was a particular area of difficulty for children with persisting speech problems. Children with speech difficulties are likely to perform less well than expected on literacy and maths SAT's at age 7. Performance is related to whether the speech problem resolves early on and whether associated language problems exist. Whilst it is unclear whether poorer performance on maths is because of the language components of this task, the results indicate that speech problems, especially persisting ones, can affect the ability to access the National Curriculum to expected levels.
von Stülpnagel, Rul; Schult, Janette C; Richter, Claudia; Steffens, Melanie C
2016-01-01
Findings from action memory research suggest that the enactment of simple actions and naturalistic activities results in similar memory performance to that from their observation. However, little is known about potential differences between the conditions during the encoding of the to-be-studied actions and activities. We analysed the cognitive costs of encoding two novel naturalistic activities studied via enactment or via observation in four experiments. In addition to memory performance, we measured objective cognitive costs with a secondary task and subjective cognitive costs with repeated ratings of mental effort and estimates of general activity difficulty. Memory performance was comparable across study conditions throughout all experiments. The enactment of activities repeatedly resulted in slower reaction times in the secondary task than did observation, suggesting higher objective costs. In contrast, subjective costs were rated lower after enactment than after observation. Findings from a pantomimic enactment condition suggested that the low ratings of subjective costs after enactment represent a misinterpretation of task demands. Our findings imply that the widespread belief about "learning by doing" as an easy way of learning does not stem from an actual advantage in memory performance, but rather from continuous feedback about one's performance resulting from enactment.
How children with cerebral palsy master bimanual activities from a parental perspective.
Lidman, Git; Himmelmann, Kate; Gosman-Hedström, Gunilla; Peny-Dahlstrand, Marie
2017-06-09
During childhood, children learn the daily life activities they want and need to do. Children with unilateral spastic cerebral palsy often have difficulties performing activities requiring two hands. To describe parental reasoning on how children with unilateral spastic cerebral palsy learn to master the performance of bimanual activities in everyday life. Sixteen parents participated in focus groups, a qualitative research approach with its own methodological criteria and research methods. One overall theme emerged from the analysis: 'Finding harmony between pleasure and effort is the key to learning'. This overall theme arose as a synthesis of four themes: 'awakening of the inner drive', 'trying on one's own', 'enabling things to work' and 'it must be worth the effort´. The parents described when an activity woke their children´s inner drive to perform. Their children also strived to develop their own way to perform an activity, sometimes with the support of others, still, some activities were not possible to learn. Occupational therapists and others in the children's environment have an important mission to support the children to find their own harmony between pleasure and effort and their individual key to success in learning bimanual everyday activities.
Psychosocial difficulties from the perspective of persons with neuropsychiatric disorders.
Coenen, Michaela; Cabello, Maria; Umlauf, Silvia; Ayuso-Mateos, José Luis; Anczewska, Marta; Tourunen, Jouni; Leonardi, Matilde; Cieza, Alarcos
2016-01-01
The objective of this study is to determine whether persons with neuropsychiatric disorders experience a common set of psychosocial difficulties using qualitative data from focus groups and individual interviews. The study was performed in five European countries (Finland, Italy, Germany, Poland and Spain) using the focus groups and individual interviews with persons with nine neuropsychiatric disorders (dementia, depression, epilepsy, migraine, multiple sclerosis, Parkinson's disease, schizophrenia, stroke and substance dependence). Digitally recorded sessions were analysed using a step-by-step qualitative and quantitative methodology resulting in the compilation of a common set of psychosocial difficulties using the International Classification of Functioning, Disability and Health (ICF) as a framework. Sixty-seven persons participated in the study. Most persons with neuropsychiatric disorders experience difficulties in emotional functions, sleeping, carrying out daily routine, working and interpersonal relationships in common. Sixteen out of 33 psychosocial difficulties made up the common set. This set includes mental functions, pain and issues addressing activities and participation and provides first evidence for the hypothesis of horizontal epidemiology of psychosocial difficulties in neuropsychiatric disorders. This study provides information about psychosocial difficulties that should be covered in the treatment and rehabilitation of persons with neuropsychiatric disorders regardless of clinical diagnoses. Emotional problems, work and sleep problems should be addressed in all the treatments of neuropsychiatric disorders regardless of their specific diagnosis, etiology and severity. Personality issues should be targeted in the treatment for neurological disorders, whereas communication skill training may also be useful for mental disorders. The effects of medication and social environment on patient's daily life should be considered in all the neuropsychiatric conditions.
Hämäläinen, H Pauliina; Suni, Jaana H; Pasanen, Matti E; Malmberg, Jarmo J; Miilunpalo, Seppo I
2006-06-01
The functional independence of elderly populations deteriorates with age. Several tests of physical performance have been developed for screening elderly persons who are at risk of losing their functional independence. The purpose of the present study was to investigate whether several components of health-related fitness (HRF) are valid in predicting the occurrence of self-reported mobility difficulties (MD) among high-functioning older adults. Subjects were community-dwelling men and women, born 1917-1941, who participated in the assessment of HRF [6.1-m (20-ft) walk, one-leg stand, backwards walk, trunk side-bending, dynamic back extension, one-leg squat, 1-km walk] and who were free of MD in 1996 (no difficulties in walking 2- km, n=788; no difficulties in climbing stairs, n=647). Postal questionnaires were used to assess the prevalence of MD in 1996 and the occurrence of new MD in 2002. Logistic regression analysis was used as the statistical method. Both inability to perform the backwards walk and a poorer result in it were associated with risk of walking difficulties in the logistic model, with all the statistically significant single test items included. Results of 1-km walk time and one-leg squat strength test were also associated with risk, although the squat was statistically significant only in two older birth cohorts. Regarding stair-climbing difficulties, poorer results in the 1-km walk, dynamic back extension and one-leg squat tests were associated with increased risk of MD. The backwards walk, one-leg squat, dynamic back extension and 1-km walk tests were the best predictors of MD. These tests are recommended for use in screening high-functioning older people at risk of MD, as well as to target physical activity counseling to those components of HRF that are important for functional independence.
Apollo 15 time and motion study
NASA Technical Reports Server (NTRS)
Kubis, J. F.; Elrod, J. T.; Rusnak, R.; Barnes, J. E.
1972-01-01
A time and motion study of Apollo 15 lunar surface activity led to examination of four distinct areas of crewmen activity. These areas are: an analysis of lunar mobility, a comparative analysis of tasks performed in 1-g training and lunar EVA, an analysis of the metabolic cost of two activities that are performed in several EVAs, and a fall/near-fall analysis. An analysis of mobility showed that the crewmen used three basic mobility patterns (modified walk, hop, side step) while on the lunar surface. These mobility patterns were utilized as adaptive modes to compensate for the uneven terrain and varied soil conditions that the crewmen encountered. A comparison of the time required to perform tasks at the final 1-g lunar EVA training sessions and the time required to perform the same task on the lunar surface indicates that, in almost all cases, it took significantly more time (on the order of 40%) to perform tasks on the moon. This increased time was observed even after extraneous factors (e.g., hardware difficulties) were factored out.
Brain waves-based index for workload estimation and mental effort engagement recognition
NASA Astrophysics Data System (ADS)
Zammouri, A.; Chraa-Mesbahi, S.; Ait Moussa, A.; Zerouali, S.; Sahnoun, M.; Tairi, H.; Mahraz, A. M.
2017-10-01
The advent of the communication systems and considering the complexity that some impose in their use, it is necessary to incorporate and equip these systems with a certain intelligence which takes into account the cognitive and mental capacities of the human operator. In this work, we address the issue of estimating the mental effort of an operator according to the cognitive tasks difficulty levels. Based on the Electroencephalogram (EEG) measurements, the proposed approach analyzes the user’s brain activity from different brain regions while performing cognitive tasks with several levels of difficulty. At a first time, we propose a variances comparison-based classifier (VCC) that makes use of the Power Spectral Density (PSD) of the EEG signal. The aim of using such a classifier is to highlight the brain regions that enter into interaction according to the cognitive task difficulty. In a second time, we present and describe a new EEG-based index for the estimation of mental efforts. The designed index is based on information recorded from two EEG channels. Results from the VCC demonstrate that powers of the Theta [4-7 Hz] (θ) and Alpha [8-12 Hz] (α) oscillations decrease while increasing the cognitive task difficulty. These decreases are mainly located in parietal and temporal brain regions. Based on the Kappa coefficients, decisions of the introduced index are compared to those obtained from an existing index. This performance assessment method revealed strong agreements. Hence the efficiency of the introduced index.
The effect of early deprivation on executive attention in middle childhood.
Loman, Michelle M; Johnson, Anna E; Westerlund, Alissa; Pollak, Seth D; Nelson, Charles A; Gunnar, Megan R
2013-01-01
Children reared in deprived environments, such as institutions for the care of orphaned or abandoned children, are at increased risk for attention and behavior regulation difficulties. This study examined the neurobehavioral correlates of executive attention in post institutionalized (PI) children. The performance and event-related potentials (ERPs) of 10- and 11-year-old internationally adopted PI children on two executive attention tasks, go/no-go and Flanker, were compared with two groups: children internationally adopted early from foster care (PF) and nonadopted children (NA). Behavioral measures suggested problems with sustained attention, with PIs performing more poorly on go trials and not on no-go trials of the go/no-go and made more errors on both congruent and incongruent trials on the Flanker. ERPs suggested differences in inhibitory control and error monitoring, as PIs had smaller N2 amplitude on go/no-go and smaller error-related negativity on Flanker. This pattern of results raises questions regarding the nature of attention difficulties for PI children. The behavioral errors are not specific to executive attention and instead likely reflect difficulties in overall sustained attention. The ERP results are consistent with neural activity related to deficits in inhibitory control (N2) and error monitoring (error-related negativity). Questions emerge regarding the similarity of attention regulatory difficulties in PIs to those experienced by non-PI children with ADHD. © 2012 The Authors. Journal of Child Psychology and Psychiatry © 2012 Association for Child and Adolescent Mental Health.
Is a Responsive Default Mode Network Required for Successful Working Memory Task Performance?
Čeko, Marta; Gracely, John L.; Fitzcharles, Mary-Ann; Seminowicz, David A.; Schweinhardt, Petra
2015-01-01
In studies of cognitive processing using tasks with externally directed attention, regions showing increased (external-task-positive) and decreased or “negative” [default-mode network (DMN)] fMRI responses during task performance are dynamically responsive to increasing task difficulty. Responsiveness (modulation of fMRI signal by increasing load) has been linked directly to successful cognitive task performance in external-task-positive regions but not in DMN regions. To investigate whether a responsive DMN is required for successful cognitive performance, we compared healthy human subjects (n = 23) with individuals shown to have decreased DMN engagement (chronic pain patients, n = 28). Subjects performed a multilevel working-memory task (N-back) during fMRI. If a responsive DMN is required for successful performance, patients having reduced DMN responsiveness should show worsened performance; if performance is not reduced, their brains should show compensatory activation in external-task-positive regions or elsewhere. All subjects showed decreased accuracy and increased reaction times with increasing task level, with no significant group differences on either measure at any level. Patients had significantly reduced negative fMRI response (deactivation) of DMN regions (posterior cingulate/precuneus, medial prefrontal cortex). Controls showed expected modulation of DMN deactivation with increasing task difficulty. Patients showed significantly reduced modulation of DMN deactivation by task difficulty, despite their successful task performance. We found no evidence of compensatory neural recruitment in external-task-positive regions or elsewhere. Individual responsiveness of the external-task-positive ventrolateral prefrontal cortex, but not of DMN regions, correlated with task accuracy. These findings suggest that a responsive DMN may not be required for successful cognitive performance; a responsive external-task-positive network may be sufficient. SIGNIFICANCE STATEMENT We studied the relationship between responsiveness of the brain to increasing task demand and successful cognitive performance, using chronic pain patients as a probe. fMRI working memory studies show that two main cognitive networks [“external-task positive” and “default-mode network” (DMN)] are responsive to increasing task difficulty. The responsiveness of both of these brain networks is suggested to be required for successful task performance. The responsiveness of external-task-positive regions has been linked directly to successful cognitive task performance, as we also show here. However, pain patients show decreased engagement and responsiveness of the DMN but can perform a working memory task as well as healthy subjects, without demonstrable compensatory neural recruitment. Therefore, a responsive DMN might not be needed for successful cognitive performance. PMID:26290236
Is a Responsive Default Mode Network Required for Successful Working Memory Task Performance?
Čeko, Marta; Gracely, John L; Fitzcharles, Mary-Ann; Seminowicz, David A; Schweinhardt, Petra; Bushnell, M Catherine
2015-08-19
In studies of cognitive processing using tasks with externally directed attention, regions showing increased (external-task-positive) and decreased or "negative" [default-mode network (DMN)] fMRI responses during task performance are dynamically responsive to increasing task difficulty. Responsiveness (modulation of fMRI signal by increasing load) has been linked directly to successful cognitive task performance in external-task-positive regions but not in DMN regions. To investigate whether a responsive DMN is required for successful cognitive performance, we compared healthy human subjects (n = 23) with individuals shown to have decreased DMN engagement (chronic pain patients, n = 28). Subjects performed a multilevel working-memory task (N-back) during fMRI. If a responsive DMN is required for successful performance, patients having reduced DMN responsiveness should show worsened performance; if performance is not reduced, their brains should show compensatory activation in external-task-positive regions or elsewhere. All subjects showed decreased accuracy and increased reaction times with increasing task level, with no significant group differences on either measure at any level. Patients had significantly reduced negative fMRI response (deactivation) of DMN regions (posterior cingulate/precuneus, medial prefrontal cortex). Controls showed expected modulation of DMN deactivation with increasing task difficulty. Patients showed significantly reduced modulation of DMN deactivation by task difficulty, despite their successful task performance. We found no evidence of compensatory neural recruitment in external-task-positive regions or elsewhere. Individual responsiveness of the external-task-positive ventrolateral prefrontal cortex, but not of DMN regions, correlated with task accuracy. These findings suggest that a responsive DMN may not be required for successful cognitive performance; a responsive external-task-positive network may be sufficient. We studied the relationship between responsiveness of the brain to increasing task demand and successful cognitive performance, using chronic pain patients as a probe. fMRI working memory studies show that two main cognitive networks ["external-task positive" and "default-mode network" (DMN)] are responsive to increasing task difficulty. The responsiveness of both of these brain networks is suggested to be required for successful task performance. The responsiveness of external-task-positive regions has been linked directly to successful cognitive task performance, as we also show here. However, pain patients show decreased engagement and responsiveness of the DMN but can perform a working memory task as well as healthy subjects, without demonstrable compensatory neural recruitment. Therefore, a responsive DMN might not be needed for successful cognitive performance. Copyright © 2015 the authors 0270-6474/15/3511596-11$15.00/0.
ERIC Educational Resources Information Center
Ho, Hsin-Ning
2010-01-01
This study examined the impact of different levels of task difficulty and expertise on self-efficacy judgments. In addition, the study examines how self-efficacy judgments affect the amount of mental effort investment and task performance under different levels of task difficulty and expertise. Results from this study are used to build a…
... is also important to address difficulties with social integration, participation in leisure activities, and maintaining stamina. The ... is also important to address difficulties with social integration, participation in leisure activities, and maintaining stamina. The ...
Genetics of Preparation and Response Control in ADHD: The Role of DRD4 and DAT1
ERIC Educational Resources Information Center
Albrecht, Björn; Brandeis, Daniel; Uebel-von Sandersleben, Henrik; Valko, Lilian; Heinrich, Hartmut; Xu, Xiaohui; Drechsler, Renate; Heise, Alexander; Kuntsi, Jonna; Müller, Ueli C.; Asherson, Philip; Steinhausen, Hans-Christoph; Rothenberger, Aribert; Banaschewski, Tobias
2014-01-01
Background: Difficulties with performance and brain activity related to attentional orienting (Cue-P3), cognitive or response preparation (Cue-CNV) and inhibitory response control (Nogo-P3) during tasks tapping executive functions are familial in ADHD and may represent endophenotypes. The aim of this study was to clarify the impact of dopamine…
Bone Marrow Function in Development of Childhood Asthma
2006-10-01
hematopoietically active parvovirus , which necessitated repetition of these experiments in healthy mice to verify experimental results. Two replicates of...initially had difficulties performing these experiments due to parvovirus infection of our mice. We have recently repeated these studies utilizing...facilities in the Office of Laboratory Animal Resources of West Virginia University was the subject of an outbreak of parvovirus that proved
Work reality perceived by individuals with impairments: a biopsychosocial experience.
Coelho, Cecília Martins; Sampaio, Rosana Ferreira; Luz, Madel Therezinha; Mancini, Marisa Cotta
2013-01-01
Individuals with different impairments are working in the formal and/or informal market despite physical and attitudinal barriers. To date, few studies have addressed this situation from the perspective of the individuals. Apprehend factors that restrict work performance in the perspective of workers with impairments and identify the strategies employed and the difficulties faced. Individuals with impairment who exercised paid activities. Thirty semi-structured interviews and eleven observations of individuals in work activities. Limitations stemming from participants' disability and health status had an influence over their execution of tasks, but did not compromise work performance. Environmental factors that impacted as facilitators or barriers were: lack of preparation of colleagues, employers, education and rehabilitation systems; attitudes and coexistence; accessibility, implementation of land use policies, urban structures and transportation; products and technology; and distributive policies. Personal factors (upbringing, self-esteem, good mood, outgoingness, communicability, willpower, age and how the disability was acquired) also influenced participation at work. Important strategies included recognizing and sharing capabilities and needs, which minimized or eliminated difficulties at work. Workers with impairments developed effective strategies for dealing with adverse situations, which remained in the individual realm. Working with impairments is a complex experience that demands overcoming old paradigms.
Colombo, Roberto; Sterpi, Irma; Mazzone, Alessandra; Delconte, Carmen; Pisano, Fabrizio
2012-05-01
In robot-assisted neurorehabilitation, matching the task difficulty level to the patient's needs and abilities, both initially and as the relearning process progresses, can enhance the effectiveness of training and improve patients' motivation and outcome. This study presents a Progressive Task Regulation algorithm implemented in a robot for upper limb rehabilitation. It evaluates the patient's performance during training through the computation of robot-measured parameters, and automatically changes the features of the reaching movements, adapting the difficulty level of the motor task to the patient's abilities. In particular, it can select different types of assistance (time-triggered, activity-triggered, and negative assistance) and implement varied therapy practice to promote generalization processes. The algorithm was tuned by assessing the performance data obtained in 22 chronic stroke patients who underwent robotic rehabilitation, in which the difficulty level of the task was manually adjusted by the therapist. Thus, we could verify the patient's recovery strategies and implement task transition rules to match both the patient's and therapist's behavior. In addition, the algorithm was tested in a sample of five chronic stroke patients. The findings show good agreement with the therapist decisions so indicating that it could be useful for the implementation of training protocols allowing individualized and gradual treatment of upper limb disabilities in patients after stroke. The application of this algorithm during robot-assisted therapy should allow an easier management of the different motor tasks administered during training, thereby facilitating the therapist's activity in the treatment of different pathologic conditions of the neuromuscular system.
ERIC Educational Resources Information Center
Jokic, Claire Sangster; Whitebread, David
2011-01-01
Children with developmental coordination disorder (DCD) experience difficulty coping with everyday demands due to difficulties in performing motor tasks. Recently, a cognitive learning paradigm has been applied to studying the nature of the problems experienced by children with DCD, which assumes that these children have fewer cognitive and…
ERIC Educational Resources Information Center
Tekin-Sitrava, Reyhan; Isiksal-Bostan, Mine
2014-01-01
This qualitative study examined middle school students' performance, solution strategies, difficulties and the underlying reasons for their difficulties in calculating the volume of a rectangular prism. The data was collected from 35 middle school students (6th, 7th and 8th grade students) enrolled in a private school in Istanbul, Turkey. The data…
Jiang, Cunmei; Lim, Vanessa K.; Wang, Hang; Hamm, Jeff P.
2013-01-01
Music processing is influenced by pitch perception and memory. Additionally these features interact, with pitch memory performance decreasing as the perceived distance between two pitches decreases. This study examined whether or not the difficulty of pitch discrimination influences pitch retention by testing individuals with congenital amusia. Pitch discrimination difficulty was equated by determining an individual’s threshold with a two down one up staircase procedure and using this to create conditions where two pitches (the standard and the comparison tones) differed by 1x, 2x, and 3x the threshold setting. For comparison with the literature a condition that employed a constant pitch difference of four semitones was also included. The results showed that pitch memory performance improved as the discrimination between the standard and the comparison tones was made easier for both amusic and control groups, and more importantly, that amusics did not show any pitch retention deficits when the discrimination difficulty was equated. In contrast, consistent with previous literature, amusics performed worse than controls when the physical pitch distance was held constant at four semitones. This impaired performance has been interpreted as evidence for pitch memory impairment in the past. However, employing a constant pitch distance always makes the difference closer to the discrimination threshold for the amusic group than for the control group. Therefore, reduced performance in this condition may simply reflect differences in the perceptual difficulty of the discrimination. The findings indicate the importance of equating the discrimination difficulty when investigating memory. PMID:24205375
Goldberg, Allon; Alexander, Neil B.
2010-01-01
Background Bending down and kneeling are fundamental tasks of daily living, yet nearly a quarter of older adults report having difficulty performing or being unable to perform these movements. Older adults with stooping, crouching, or kneeling (SCK) difficulty have demonstrated an increased fall risk. Strength (force-generating capacity) measures may be useful for determining both SCK difficulty and fall risk. Objective The purposes of this study were: (1) to examine muscle strength differences in older adults with and without SCK difficulty and (2) to examine the relative contributions of trunk and leg muscle strength to SCK difficulty. Design This was a cross-sectional observational study. Methods Community-dwelling older adults (age [X̅±SD]=75.5±6.0 years) with SCK difficulty (n=27) or without SCK difficulty (n=21) were tested for leg and trunk strength and functional mobility. Isometric strength at the trunk, hip, knee, and ankle also was normalized by body weight and height. Results Compared with older adults with no SCK difficulty, those with SCK difficulty had significant decreases in normalized trunk extensor, knee extensor, and ankle dorsiflexor and plantar-flexor strength. In 2 separate multivariate analyses, raw ankle plantar-flexor strength (odds ratio [OR]=0.97, 95% confidence interval [CI]=0.95–0.99) and normalized knee extensor strength (OR=0.61, 95% CI=0.44–0.82) were significantly associated with SCK difficulty. Stooping, crouching, and kneeling difficulty also correlated with measures of functional balance and falls. Limitations Although muscle groups that were key to rising from SCK were examined, there are other muscle groups that may contribute to safe SCK performance. Conclusions Decreased muscle strength, particularly when normalized for body size, predicts SCK difficulty. These data emphasize the importance of strength measurement at multiple levels in predicting self-reported functional impairment. PMID:19942678
Dasgupta, Annwesa P.; Anderson, Trevor R.
2014-01-01
It is essential to teach students about experimental design, as this facilitates their deeper understanding of how most biological knowledge was generated and gives them tools to perform their own investigations. Despite the importance of this area, surprisingly little is known about what students actually learn from designing biological experiments. In this paper, we describe a rubric for experimental design (RED) that can be used to measure knowledge of and diagnose difficulties with experimental design. The development and validation of the RED was informed by a literature review and empirical analysis of undergraduate biology students’ responses to three published assessments. Five areas of difficulty with experimental design were identified: the variable properties of an experimental subject; the manipulated variables; measurement of outcomes; accounting for variability; and the scope of inference appropriate for experimental findings. Our findings revealed that some difficulties, documented some 50 yr ago, still exist among our undergraduate students, while others remain poorly investigated. The RED shows great promise for diagnosing students’ experimental design knowledge in lecture settings, laboratory courses, research internships, and course-based undergraduate research experiences. It also shows potential for guiding the development and selection of assessment and instructional activities that foster experimental design. PMID:26086658
Annotating smart environment sensor data for activity learning.
Szewcyzk, S; Dwan, K; Minor, B; Swedlove, B; Cook, D
2009-01-01
The pervasive sensing technologies found in smart homes offer unprecedented opportunities for providing health monitoring and assistance to individuals experiencing difficulties living independently at home. In order to monitor the functional health of smart home residents, we need to design technologies that recognize and track the activities that people perform at home. Machine learning techniques can perform this task, but the software algorithms rely upon large amounts of sample data that is correctly labeled with the corresponding activity. Labeling, or annotating, sensor data with the corresponding activity can be time consuming, may require input from the smart home resident, and is often inaccurate. Therefore, in this paper we investigate four alternative mechanisms for annotating sensor data with a corresponding activity label. We evaluate the alternative methods along the dimensions of annotation time, resident burden, and accuracy using sensor data collected in a real smart apartment.
Gao, Zan; Podlog, Leslie
2012-10-01
To examine the effects of different levels of goal specificity and difficulty on Latino children's performance and physical activity (PA) levels in an after-school program incorporating an interactive dance program (Dance Dance Revolution [DDR]; Konami Corporation). Comparison study. Rose Park Elementary School, Salt Lake City, Utah. Ninety-eight Latino children in the first through sixth grades, aged 7 to 13 years. After the pretest, the participants were randomly assigned into 1 of the following 3 goal-setting conditions: (1) easy, (2) difficult, and (3) best effort (hereinafter referred to as do-your-best goal). Participants' PA levels were measured using piezoelectric pedometers, and steps per minute were used as the outcome variable. Participants' total points for their dance on television screens were retrieved as their performance scores. These outcome variables were assessed again 8 weeks later (posttest score). The multivariate analysis of covariance yielded a significant main effect for the goal-setting condition. Follow-up tests revealed that children who set specific (easy or difficult) goals had significantly greater increased PA levels (mean scores, 10.34 for easy and 22.45 for difficult) and DDR performance (0.011 for easy and 0.67 for difficult) than those in the do-your-best group (0.83 for PA and 0.17 for performance). In addition, children's increased PA levels in the difficult-goal group were significantly higher than those in the easy-goal group. The easy- and difficult-goal groups show a significant improvement on DDR performance. The difficult- goal group also displays the highest improvement on PA levels. Strategies to enhance children's DDR performance and PA levels are discussed in relation to the extant goal-setting literature.
Mizuno, Kei; Tanaka, Masaaki; Tanabe, Hiroki C; Sadato, Norihiro; Watanabe, Yasuyoshi
2012-07-01
The kana pick-out test has been widely used in Japan to evaluate the ability to divide attention in both adult and pediatric patients. However, the neural substrates underlying the ability to divide attention using the kana pick-out test, which requires participants to pick out individual letters (vowels) in a story while also reading for comprehension, thus requiring simultaneous allocation of attention to both activities, are still unclear. Moreover, outside of the clinical area, neuroimaging studies focused on the mechanisms of divided attention during complex story comprehension are rare. Thus, the purpose of the present study, to clarify the neural substrates of kana pick-out test, improves our current understanding of the basic neural mechanisms of dual task performance in verbal memory function. We compared patterns of activation in the brain obtained during performance of the individual tasks of vowel identification and story comprehension, to levels of activation when participants performed the two tasks simultaneously during the kana pick-out test. We found that activations of the left dorsal inferior frontal gyrus and superior parietal lobule increase in functional connectivity to a greater extent during the dual task condition compared to the two single task conditions. In contrast, activations of the left fusiform gyrus and middle temporal gyrus, which are significantly involved in picking out letters and complex sentences during story comprehension, respectively, were reduced in the dual task condition compared to during the two single task conditions. These results suggest that increased activations of the dorsal inferior frontal gyrus and superior parietal lobule during dual task performance may be associated with the capacity for attentional resources, and reduced activations of the left fusiform gyrus and middle temporal gyrus may reflect the difficulty of concurrent processing of the two tasks. In addition, the increase in synchronization between the left dorsal inferior frontal gyrus and superior parietal lobule in the dual task condition may induce effective communication between these brain regions and contribute to more attentional processing than in the single task condition, due to greater and more complex demands on voluntary attentional resources. Copyright © 2012 Elsevier Ltd. All rights reserved.
Human target acquisition performance
NASA Astrophysics Data System (ADS)
Teaney, Brian P.; Du Bosq, Todd W.; Reynolds, Joseph P.; Thompson, Roger; Aghera, Sameer; Moyer, Steven K.; Flug, Eric; Espinola, Richard; Hixson, Jonathan
2012-06-01
The battlefield has shifted from armored vehicles to armed insurgents. Target acquisition (identification, recognition, and detection) range performance involving humans as targets is vital for modern warfare. The acquisition and neutralization of armed insurgents while at the same time minimizing fratricide and civilian casualties is a mounting concern. U.S. Army RDECOM CERDEC NVESD has conducted many experiments involving human targets for infrared and reflective band sensors. The target sets include human activities, hand-held objects, uniforms & armament, and other tactically relevant targets. This paper will define a set of standard task difficulty values for identification and recognition associated with human target acquisition performance.
Ganesh, Suma; Sethi, Sumita; Srivastav, Sonia; Chaudhary, Amrita; Arora, Priyanka
2013-09-01
To evaluate the impact of low vision rehabilitation on functional vision of children with visual impairment. The LV Prasad-Functional Vision Questionnaire, designed specifically to measure functional performance of visually impaired children of developing countries, was used to assess the level of difficulty in performing various tasks pre and post visual rehabilitation in children with documented visual impairment. Chi-square test was used to assess the impact of rehabilitation intervention on functional vision performance; a P < 0.05 was considered significant. LogMAR visual acuity prior to the introduction of low vision devices (LVDs) was 0.90 ± 0.05 for distance and for near it was 0.61 ± 0.05. After the intervention, the acuities improved significantly for distance (0.2 ± 0.27; P < 0.0001) and near (0.42 ± 0.17; P = 0.001). The most common reported difficulties were related to their academic activities like copying from the blackboard (80%), reading textbook at arm's length (77.2%), and writing along a straight line (77.2%). Absolute raw score of disability pre-LVD was 15.05 which improved to 7.58 post-LVD. An improvement in functional vision post visual rehabilitation was especially found in those activities related to their studying lifestyle like copying from the blackboard (P < 0.0001), reading textbook at arm's length (P < 0.0001), and writing along a straight line (P = 0.003). In our study group, there was a significant improvement in functional vision post visual rehabilitation, especially with those activities which are related to their academic output. It is important for these children to have an early visual rehabilitation to decrease the impairment associated with these decreased visual output and to enhance their learning abilities.
2012-01-01
Background The motivation of patients during robot-assisted rehabilitation after neurological disorders that lead to impairments of motor functions is of great importance. Due to the increasing number of patients, increasing medical costs and limited therapeutic resources, clinicians in the future may want patients to practice their movements at home or with reduced supervision during their stay in the clinic. Since people only engage in an activity and are motivated to practice if the outcome matches the effort at which they perform, an augmented feedback application for rehabilitation should take the cognitive and physical deficits of patients into account and incorporate a mechanism that is capable of balancing i.e. adjusting the difficulty of an exercise in an augmented feedback application to the patient's capabilities. Methods We propose a computational mechanism based on Fitts' Law that balances i.e. adjusts the difficulty of an exercise for upper-extremity rehabilitation. The proposed mechanism was implemented into an augmented feedback application consisting of three difficulty conditions (easy, balanced, hard). The task of the exercise was to reach random targets on the screen from a starting point within a specified time window. The available time was decreased with increasing condition difficulty. Ten subacute stroke patients were recruited to validate the mechanism through a study. Cognitive and motor functions of patients were assessed using the upper extremity section of the Fugl-Meyer Assessment, the modified Ashworth scale as well as the Addenbrookes cognitive examination-revised. Handedness of patients was obtained using the Edinburgh handedness inventory. Patients' performance during the execution of the exercises was measured twice, once for the paretic and once for the non-paretic arm. Results were compared using a two-way ANOVA. Post hoc analysis was performed using a Tukey HSD with a significance level of p < 0.05. Results Results show that the mechanism was capable of balancing the difficulty of an exercise to the capabilities of the patients. Medians for both arms show a gradual decrease and significant difference of the number of successful trials with increasing condition difficulty (F2;60 = 44.623; p < 0.01; η2 = 0.623) but no significant difference between paretic and non-paretic arm (F1;60 = 3.768; p = 0.057; η2 = 0.065). Post hoc analysis revealed that, for both arms, the hard condition significantly differed from the easy condition (p < 0.01). In the non-paretic arm there was an additional significant difference between the balanced and the hard condition (p < 0.01). Reducing the time to reach the target, i.e., increasing the difficulty level, additionally revealed significant differences between conditions for movement speeds (F2;59 = 6.013; p < 0.01; η2 = 0.185), without significant differences for hand-closing time (F2;59 = 2.620; p = 0.082; η2 = 0.09), reaction time (F2;59 = 0.978; p = 0.383; η2 = 0.036) and hand-path ratio (F2;59 = 0.054; p = 0.947; η2 = 0.002). The evaluation of a questionnaire further supported the assumption that perceived performance declined with increased effort and increased exercise difficulty leads to frustration. Conclusions Our results support that Fitts' Law indeed constitutes a powerful mechanism for task difficulty adaptation and can be incorporated into exercises for upper-extremity rehabilitation. PMID:22304989
Altered Network Oscillations and Functional Connectivity Dynamics in Children Born Very Preterm.
Moiseev, Alexander; Doesburg, Sam M; Herdman, Anthony T; Ribary, Urs; Grunau, Ruth E
2015-09-01
Structural brain connections develop atypically in very preterm children, and altered functional connectivity is also evident in fMRI studies. Such alterations in brain network connectivity are associated with cognitive difficulties in this population. Little is known, however, about electrophysiological interactions among specific brain networks in children born very preterm. In the present study, we recorded magnetoencephalography while very preterm children and full-term controls performed a visual short-term memory task. Regions expressing task-dependent activity changes were identified using beamformer analysis, and inter-regional phase synchrony was calculated. Very preterm children expressed altered regional recruitment in distributed networks of brain areas, across standard physiological frequency ranges including the theta, alpha, beta and gamma bands. Reduced oscillatory synchrony was observed among task-activated brain regions in very preterm children, particularly for connections involving areas critical for executive abilities, including middle frontal gyrus. These findings suggest that inability to recruit neurophysiological activity and interactions in distributed networks including frontal regions may contribute to difficulties in cognitive development in children born very preterm.
Badenes, Dolors; Garolera, Maite; Casas, Laura; Cejudo-Bolivar, Juan Carlos; de Francisco, Jorge; Zaragoza, Silvia; Calzado, Noemi; Aguilar, Miquel
2014-05-01
Multiple Sclerosis (MS) significantly impacts daily living activities, including car driving. To investigate driving difficulties experienced with MS, we compared 50 MS patients with minor or moderate disability and 50 healthy controls (HC) using computerized driving tests (the ASDE driver test and the Useful Field of View (UFOV) test) and neuropsychological tests. Inclusion criteria included being active drivers. We evaluated whether cognitive deterioration in MS is associated with the results of driving tests by comparing MS patients without cognitive deterioration with HC. The results indicated that the MS patients performed worse than the HCs in attention, information processing, working memory and visuomotor coordination tasks. Furthermore, MS patients with cognitive impairments experienced more difficulties in the driving tests than did the non-impaired MS patients. Motor dysfunction associated with MS also played an important role in this activity. The results of this study suggest that MS should be assessed carefully and that special emphasis should be placed on visuomotor coordination and executive functions because patients with minor motor disability and subtle cognitive impairments can pass measures predictive of driving safety.
Breivik, Ingrid; Hemmingsson, Helena
2013-09-01
Adolescents with Asperger's syndrome (AS), often have handwriting difficulties that affect their academic performance. The purpose of this descriptive multiple-case mixed-method study was to highlight how adolescents with AS experience writing in the school setting when writing by hand and when using a computerized Assistive Technology Device (ATD), for writing. A qualitative content analysis approach was used, including interviews with five adolescents, their parents, and their teachers. This was complemented by asking the adolescents to rate their perceived performance and satisfaction of writing with and without the ATD. All adolescents described handwriting difficulties, but a reduced ability to express oneself in writing was also common. Initiating and completing writing tasks was often so demanding that it caused resistance to the activity. Several advantages when using the ATD were described by the participants and the self-ratings showed higher scores for performance of and satisfaction with writing when the ATD was used. The results show that teachers' encouragement seemed to be important for the initiation and continuation of use of the ATD.
Attout, Lucie; Salmon, Eric; Majerus, Steve
2015-01-01
Recent studies suggest that order working memory (WM) may be specifically associated with numerical abilities. This study explored behavioral performance and neural networks associated with verbal WM in adults with a history of developmental dyscalculia (DD). The DD group performed significantly poorer but with the same precision than the control group in order WM tasks and showed a lower activation of the right middle frontal gyrus during the order WM and the alphabetical order judgment tasks. This study suggests a persistent impairment in order WM in adults with DD, characterized by more general difficulties in controlled activation of order information.
Spatial-sequential and spatial-simultaneous working memory in individuals with Williams syndrome.
Lanfranchi, Silvia; De Mori, Letizia; Mammarella, Irene C; Carretti, Barbara; Vianello, Renzo
2015-05-01
The aim of the present study was to compare visuospatial working memory performance in 18 individuals with Williams syndrome (WS) and 18 typically developing (TD) children matched for nonverbal mental age. Two aspects were considered: task presentation format (i.e., spatial-sequential or spatial-simultaneous), and level of attentional control (i.e., passive or active tasks). Our results showed that individuals with WS performed less well than TD children in passive spatial-simultaneous tasks, but not in passive spatial-sequential tasks. The former's performance was also worse in both active tasks. These findings suggest an impairment in the spatial-simultaneous working memory of individuals with WS, together with a more generalized difficulty in tasks requiring information storage and concurrent processing, as seen in other etiologies of intellectual disability.
Lakes, Kimberley D
2013-10-01
The purpose of this study is to report psychometric properties of scores obtained using a novel observer-rated measure of children's self-regulation, the Response to Challenge Scale (RCS). The RCS was developed to rate children's self-regulatory abilities in a physically active context (e.g., while completing a physical challenge course). The RCS and other study measures were administered in a private school sample of 207 children. Analyses of score distributions indicated that the RCS was able to capture variance among children in self-regulatory abilities; the distribution was normal for the Affective, Cognitive, and Total Self-Regulation scales. Validity analyses revealed significant positive correlations between Cognitive, Affective, Motor, and Total Self-Regulation and executive function task performance; significant negative correlations between Cognitive Regulation and teacher-rated hyperactivity and inattention; significant negative correlations between Affective, Motor, and Total Self-Regulation and teacher ratings of peer problems; and significant positive correlations between Cognitive and Affective Regulation and parent ratings of prosocial behavior. Parent and teacher rated Total Difficulties scores were both negatively correlated with RCS Total Self-Regulation scores. Results suggest that it is possible for observers to rate self-regulatory abilities in the context of physical activities, and that these ratings correspond with performance on tasks requiring executive function as well as teacher and parent ratings of children's difficulties.
Montani, Veronica; De Filippo De Grazia, Michele; Zorzi, Marco
2014-01-01
A growing body of evidence suggests that action videogames could enhance a variety of cognitive skills and more specifically attention skills. The aim of this study was to develop a novel adaptive videogame to support the rehabilitation of the most common consequences of traumatic brain injury (TBI), that is the impairment of attention and executive functions. TBI patients can be affected by psychomotor slowness and by difficulties in dealing with distraction, maintain a cognitive set for a long time, processing different simultaneously presented stimuli, and planning purposeful behavior. Accordingly, we designed a videogame that was specifically conceived to activate those functions. Playing involves visuospatial planning and selective attention, active maintenance of the cognitive set representing the goal, and error monitoring. Moreover, different game trials require to alternate between two tasks (i.e., task switching) or to perform the two tasks simultaneously (i.e., divided attention/dual-tasking). The videogame is controlled by a multidimensional adaptive algorithm that calibrates task difficulty on-line based on a model of user performance that is updated on a trial-by-trial basis. We report simulations of user performance designed to test the adaptive game as well as a validation study with healthy participants engaged in a training protocol. The results confirmed the involvement of the cognitive abilities that the game is supposed to enhance and suggested that training improved attentional control during play.
Montani, Veronica; De Filippo De Grazia, Michele; Zorzi, Marco
2014-01-01
A growing body of evidence suggests that action videogames could enhance a variety of cognitive skills and more specifically attention skills. The aim of this study was to develop a novel adaptive videogame to support the rehabilitation of the most common consequences of traumatic brain injury (TBI), that is the impairment of attention and executive functions. TBI patients can be affected by psychomotor slowness and by difficulties in dealing with distraction, maintain a cognitive set for a long time, processing different simultaneously presented stimuli, and planning purposeful behavior. Accordingly, we designed a videogame that was specifically conceived to activate those functions. Playing involves visuospatial planning and selective attention, active maintenance of the cognitive set representing the goal, and error monitoring. Moreover, different game trials require to alternate between two tasks (i.e., task switching) or to perform the two tasks simultaneously (i.e., divided attention/dual-tasking). The videogame is controlled by a multidimensional adaptive algorithm that calibrates task difficulty on-line based on a model of user performance that is updated on a trial-by-trial basis. We report simulations of user performance designed to test the adaptive game as well as a validation study with healthy participants engaged in a training protocol. The results confirmed the involvement of the cognitive abilities that the game is supposed to enhance and suggested that training improved attentional control during play. PMID:24860529
Oehl, M; Sutter, C
2015-05-01
With aging visual feedback becomes increasingly relevant in action control. Consequently, visual device and task characteristics should more and more affect tool use. Focussing on late working age, the present study aims to investigate age-related differences in processing task irrelevant (display size) and task relevant visual information (task difficulty). Young and middle-aged participants (20-35 and 36-64 years of age, respectively) sat in front of a touch screen with differently sized active touch areas (4″ to 12″) and performed pointing tasks with differing task difficulties (1.8-5 bits). Both display size and age affected pointing performance, but the two variables did not interact and aiming duration moderated both effects. Furthermore, task difficulty affected the pointing durations of middle-aged adults moreso than those of young adults. Again, aiming duration accounted for the variance in the data. The onset of an age-related decline in aiming duration can be clearly located in middle adulthood. Thus, the fine psychomotor ability "aiming" is a moderator and predictor for age-related differences in pointing tasks. The results support a user-specific design for small technical devices with touch interfaces. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Yamada, Takashi; Ohta, Haruhisa; Watanabe, Hiromi; Kanai, Chieko; Tani, Masayuki; Ohno, Taisei; Takayama, Yuko; Iwanami, Akira; Kato, Nobumasa; Hashimoto, Ryuichiro
2012-01-01
Individuals with autism spectrum condition (ASC) are known to excel in some perceptual cognitive tasks, but such developed functions have been often regarded as “islets of abilities” that do not significantly contribute to broader intellectual capacities. However, recent behavioral studies have reported that individuals with ASC have advantages for performing Raven's (Standard) Progressive Matrices (RPM/RSPM), a standard neuropsychological test for general fluid intelligence, raising the possibility that ASC′s cognitive strength can be utilized for more general purposes like novel problem solving. Here, the brain activity of 25 adults with high-functioning ASC and 26 matched normal controls (NC) was measured using functional magnetic resonance imaging (fMRI) to examine neural substrates of geometric reasoning during the engagement of a modified version of the RSPM test. Among the frontal and parietal brain regions involved in fluid intelligence, ASC showed larger activation in the left lateral occipitotemporal cortex (LOTC) during an analytic condition with moderate difficulty than NC. Activation in the left LOTC and ventrolateral prefrontal cortex (VLPFC) increased with task difficulty in NC, whereas such modulation of activity was absent in ASC. Furthermore, functional connectivity analysis revealed a significant reduction of activation coupling between the left inferior parietal cortex and the right anterior prefrontal cortex during both figural and analytic conditions in ASC. These results indicate altered pattern of functional specialization and integration in the neural system for geometric reasoning in ASC, which may explain its atypical cognitive pattern, including performance on the Raven's Matrices test. PMID:22912831
Patient perceptions about illness self-management in ANCA-associated small vessel vasculitis.
Thorpe, C T; DeVellis, R F; Blalock, S J; Hogan, S L; Lewis, M A; DeVellis, B M
2008-06-01
To characterize patient perceptions, related to eight self-management behaviours relevant for adults with ANCA-associated small vessel vasculitis (ANCA-SVV), and to determine if these perceptions were associated with performance of each behaviour. Adults with ANCA-SVV (n = 202) completed a self-administered questionnaire that assessed eight self-management behaviours (adherence to recommendations for medication, health service use, diet, exercise, infection avoidance and symptom monitoring; prompt reporting of symptoms and side effects; and adjusting activities in response to symptoms), perceptions about these behaviours, socio-demographics, clinical factors and social desirability bias. Descriptive statistics were generated to characterize patients' perceptions about difficulty of, importance of, and specific barriers to performing each behaviour. Regression analyses explored whether these variables were associated with performing each behaviour, controlling for potential confounders. With few exceptions, higher perceived importance and lower perceived difficulty of each behaviour were associated with more frequent performance of the behaviour. For each behaviour, several specific barriers were frequently endorsed by patients and a number of these were associated with lower levels of self-management. This study reveals that patient perceptions about the illness and its treatment influence ANCA-SVV self-management. Perceived barriers to medication, health services, diet and exercise adherence were similar to those in other illnesses. This study also provides insight into barriers experienced by patients in performing behaviours (infection avoidance, symptom monitoring, reporting symptoms and side-effects and adjusting activities) not often previously studied. How the identification of these barriers can help inform future interventions for ANCA-SVV patients is to be discussed.
Joffe, Victoria L; Black, Emma
2012-10-01
Adolescence is a time of transition when young people with language difficulties are at increased risk of experiencing social, emotional, and behavioral difficulties (SEBD). Most studies of social, emotional, and behavioral functioning (SEBF) in individuals with language difficulties focus on children with a clinical diagnosis of language impairment. This study explores SEBF in a nonclinical group of 12-year-old students with low educational and language performance from their own perspectives and those of their parents and teachers. The Strengths and Difficulties Questionnaire ( Goodman, 1997) was given to 352 mainstream secondary school students who were underperforming academically and had poor language performance. Two hundred and twenty-five of their parents and 230 of their teachers also completed the questionnaire. Students with low educational attainment and poor language showed significantly greater SEBD than a normative sample as reported by themselves, their parents, and their teachers. Significant differences were found across informants, with students identifying more overall difficulties than parents or teachers. Secondary school students with low academic and language performance are more vulnerable to experiencing SEBD compared to typically developing peers. The extent of their difficulties varied depending on the informant, emphasizing the importance of gaining views from multiple perspectives.
ERIC Educational Resources Information Center
Martin, Sarah H.; Martin, Michael A.
2001-01-01
Describes two classroom activities that can be implemented in accordance with the best practices revealed by current research on reading instruction with learning disabled students. Describes what research suggests for promoting comprehension for students with reading difficulties. Describes instructional sequences for two literacy activities,…
Mendoza, Nohora Marcela; González, Nohora Elizabeth
2015-01-01
One of the most important activities for quality assurance of malaria diagnosis is performance assessment. In Colombia, performance assessment of malaria microscopists has been done through the external performance assessment and indirect external performance assessment programs. To assess the performance of malaria microscopists of public reference laboratories using slide sets, and to describe the methodology used for this purpose. This was a retrospective study to evaluate the concordance of senior microscopists regarding parasite detection, species identification and parasite count based on the results of the assessment of competences using two sets, one comprising 40 slides, and another one with 17 slides. The concordance for parasite detection was 96.9% (95% CI: 96.0-97.5) and 88.7% (95% CI: 86.6-90.5) for species identification. The average percentage of concordant slides in the group evaluated was 89.7% (95% CI: 87.5-91.6). Most of the senior microscopists in Colombia were classified in the two top categories in the performance assessment using slide sets. The most common difficulty encountered was the identification of parasite species. The use of this tool to assess individual performance of microscopists in the evaluation of samples with different degrees of difficulty allows for characterizing the members of the malaria diagnosis network and strengthening the abilities of those who require it.
Damico, Jack S; Abendroth, Kathleen J; Nelson, Ryan L; Lynch, Karen E; Damico, Holly L
2011-08-01
This research report provides additional data, manifestations and discussion about avoidance strategies employed by a language-learning disabled student during reading activities. Rather than seeing avoidance as due to random distractions or oppositional behaviours, these data provide a rationale for viewing many types of avoidance as systematic and compensatory efforts to sustain interactional success in the emergence of linguistic difficulty.
ERIC Educational Resources Information Center
Travers, Brittany G.; Bigler, Erin D.; Duffield, Tyler C.; Prigge, Molly D. B.; Froehlich, Alyson L.; Lange, Nicholas; Alexander, Andrew L.; Lainhart, Janet E.
2017-01-01
Many individuals with autism spectrum disorder (ASD) exhibit motor difficulties, but it is unknown whether manual motor skills improve, plateau, or decline in ASD in the transition from childhood into adulthood. Atypical development of manual motor skills could impact the ability to learn and perform daily activities across the life span. This…
Ziebertz, Carla M.; van Hooff, Madelon L. M.; Beckers, Debby G. J.; Hooftman, Wendela E.; Kompier, Michiel A. J.; Geurts, Sabine A. E.
2015-01-01
Objectives. This study examined the relationship between on-call duty exposure (active and total on-call hours a month, number of calls per duty) and employees' experiences of being on-call (stress due to unpredictability, ability to relax during inactive on-call periods, restrictions during on-call duties, on-call work demands, and satisfaction with compensation for on-call duties) on the one hand and fatigue, strain-based and time-based work-home interference (WHI), and perceived on-call performance difficulties (PPD) on the other hand. Methods. Cross-sectional survey data were collected among a large heterogeneous sample of Dutch employees (N = 5437). The final sample consisted of 157 on-call workers (23–69 years, 71% males). Data were analyzed by means of hierarchical regression analyses (controlling for age and job characteristics). Results. Differences in on-call work exposure were not systematically related to fatigue, WHI, and PPD (all p's >0.50). The experience of being on-call explained a medium proportion of the variation in fatigue and strain-based WHI and a medium to large proportion of the variation in time-based WHI and PPD over and above the control variables. Conclusions. Our results suggest that it is employees' experience of being on-call, especially the experience of stress due to the unpredictability, rather than the amount of exposure, that is related to fatigue, WHI, and perceived on-call performance difficulties. PMID:26558276
Farrell, Meagan T.; Zahodne, Laura B.; Stern, Yaakov; Dorrejo, Jhedy; Yeung, Philip; Cosentino, Stephanie
2014-01-01
Objectives To assess the influence of subjective word-finding difficulty on Alzheimer’s disease (AD) patients’ likelihood of engaging in social leisure activities. Design Analysis of data collected from the second cohort of the Multicenter Study of Predictors of Disease Course in Alzheimer’s disease. Setting Four study sites in the U.S. and France. Participants Individuals diagnosed with mild to moderate AD (N = 236) Measurements On separate questionnaires, patients were asked to 1) report whether had trouble finding the right word when speaking (subjective word-finding difficulty), and 2) rate their frequency and enjoyment of both social and nonsocial leisure activities. Objective language measures included object naming and verbal fluency. Measures of dependence, depression, cognitive status, age, sex, and education were also included as covariates in regression analyses. Results Over half (52%) of the sample reported word-finding difficulty, and subjective complaints were correlated with poorer verbal fluency scores. Subjective word-finding difficulty was uniquely related to social activity measures. Endorsers of word-finding difficulty reported reduced frequency and enjoyment of social leisure activities, controlling for covariates. In contrast, engagement in nonsocial activities was associated with higher age and depression scores, but was not related to word-finding complaints. These results were corroborated by the caregivers’ reports, and occurred above and beyond the effect of objective word-finding ability. Conclusion AD patients who are aware of increasing word-finding failures are less likely to participate in and enjoy socially-oriented leisure activities. This finding may have significant implications for clinical and health outcomes in AD. A failure to evaluate subjective language complaints could result in social withdrawal symptoms, thereby threatening the patient’s quality of life as well as increasing caregiver burden. Importantly, reduced social interaction may ultimately exacerbate language symptoms over time. PMID:24890186
Task difficulty modulates brain activation in the emotional oddball task.
Siciliano, Rachel E; Madden, David J; Tallman, Catherine W; Boylan, Maria A; Kirste, Imke; Monge, Zachary A; Packard, Lauren E; Potter, Guy G; Wang, Lihong
2017-06-01
Previous functional magnetic resonance imaging (fMRI) studies have reported that task-irrelevant, emotionally salient events can disrupt target discrimination, particularly when attentional demands are low, while others demonstrate alterations in the distracting effects of emotion in behavior and neural activation in the context of attention-demanding tasks. We used fMRI, in conjunction with an emotional oddball task, at different levels of target discrimination difficulty, to investigate the effects of emotional distractors on the detection of subsequent targets. In addition, we distinguished different behavioral components of target detection representing decisional, nondecisional, and response criterion processes. Results indicated that increasing target discrimination difficulty led to increased time required for both the decisional and nondecisional components of the detection response, as well as to increased target-related neural activation in frontoparietal regions. The emotional distractors were associated with activation in ventral occipital and frontal regions and dorsal frontal regions, but this activation was attenuated with increased difficulty. Emotional distraction did not alter the behavioral measures of target detection, but did lead to increased target-related frontoparietal activation for targets following emotional images as compared to those following neutral images. This latter effect varied with target discrimination difficulty, with an increased influence of the emotional distractors on subsequent target-related frontoparietal activation in the more difficult discrimination condition. This influence of emotional distraction was in addition associated specifically with the decisional component of target detection. These findings indicate that emotion-cognition interactions, in the emotional oddball task, vary depending on the difficulty of the target discrimination and the associated limitations on processing resources. Copyright © 2017 Elsevier B.V. All rights reserved.
Motions and crew responses on an offshore oil production and storage vessel.
Haward, Barbara M; Lewis, Christopher H; Griffin, Michael J
2009-09-01
The motions of vessels may interfere with crew activities and well-being, but the relationships between motion and the experiences of crew are not well-established. Crew responses to motions of a floating production and storage offshore vessel at a fixed location in the North Sea were studied over a 5-month period to identify any changes in crew difficulties and symptoms associated with changes in vessel motion. Ship motions in all six axes (fore-aft, lateral, vertical, roll, pitch, and yaw) were recorded continuously over the 5-month period while 47 crew completed a total of 1704 daily diary entries, a participation rate of 66-78% of the crew complement. The dominant oscillations had frequencies of around 0.1 Hz, producing magnitudes of translational oscillation in accommodation areas of up to about 0.7 ms(-2)r.m.s., depending on the weather, and magnitudes up to three times greater in some other areas. The daily diaries gave ratings of difficulties with tasks, effort level, motion sickness, health symptoms, fatigue, and sleep. Problems most strongly associated with vessel motions were difficulties with physical tasks (balancing, moving and carrying), and sleep problems. Physical and mental tiredness, cognitive aspects of task performance, and stomach awareness and dizziness were also strongly associated with motion magnitude. There was a vomiting incidence of 3.1%, compared with a predicted mean vomiting incidence of 9.3% for a mixed population of unadapted adults. It is concluded that crew difficulties increase on days when vessel motions increase, with some activities and responses particularly influenced by vessel motions.
Rosselló, Jeannette; Maysonet Guzmán, Marielisa
2006-12-01
Insulin-dependent diabetes mellitus (IDDM) is a chronic health condition that affects 18 of every 100,000 Puerto Rican youth. Few research studies have been performed on the problems that youth with diabetes encounter and how they are related to adherence to treatment and adequate metabolic control. Adequate metabolic control is associated with fewer short and long-term medical complications, as well as better quality of life. Adapting to the demands and stressors associated with IDDM and its treatment is a task that can prove to be difficult for youth with diabetes due to having to make adjustments, alterations, and following a prescribed regimen in their daily activities. The main purpose of this investigation was to explore difficulties and worries identified by Puerto Rican youth with IDDM. This study examined whether there is a relationship between difficulties and worries, and adequate metabolic control, hopelessness, social support and depressive symptomatology. One hundred and one youth with IDDM between the ages of 8 and 17 (45 male, 56 female) were evaluated. Analysis of frequencies, correlations, and comparison tests were performed by group (gender, age, diabetes duration, and metabolic control. Results reveal that some of the difficulties identified by Puerto Rican youth with IDDM were: not eating candy and/or cake, self-monitoring blood glucose at school, doing things on time, and waking up early. Among the worries they reported were: insulin reactions and thinking that they might have to go to the hospital.
NASA Technical Reports Server (NTRS)
Bortolussi, Michael R.; Hart, Sandra G.; Shively, Robert J.
1987-01-01
A simulation was conducted to determine whether the sensitivity of secondary task measures of pilot workload could be improved by synchronizing their presentation to the occurrence of specific events or pilot actions. This synchronous method of presentation was compared to the more typical asynchronous method, where secondary task presentations are independent of pilot's flight-related activities. Twelve pilots flew low- and high-difficulty scenarios in a motion-base trainer with and without concurrent secondary tasks (e.g., choice reaction time and time production). The difficulty of each scenario was manipulated by the addition of 21 flight-related tasks superimposed on a standard approach and landing sequence. The insertion of the secondary tasks did not affect primary flight performance. However, secondary task performance did reflect workload differences between scenarios and among flight segments within scenarios, replicating the results of an earlier study in which the secondary tasks were presented asynchronously (Bortolussi et al., 1986).
Persistent Handwriting Difficulties in Children With ADHD After Treatment With Stimulant Medication.
Brossard-Racine, Marie; Shevell, Michael; Snider, Laurie; Bélanger, Stacey Ageranioti; Julien, Marilyse; Majnemer, Annette
2015-07-01
Children with ADHD often present with handwriting difficulties. However, the extent to which motor and attention skills influence performance in this group has not yet been explored. The objective of this study was to examine the factors associated with change in handwriting performance. This study examines the factors associated with change in handwriting performance of 49 children newly diagnosed with ADHD (mean age = 8.4 [SD=1.3] years) prior to and 3 months following use of a stimulant medication. Handwriting legibility and speed improved significantly at follow-up evaluation. However, most of the children with legibility difficulties at baseline continued to demonstrate difficulties when evaluated 3 months after initiation of medication. Change in handwriting legibility was best determined by improvements in visual-motor integration skills (β = 0.07-0.10; p < .001), while the change in speed did not appear to be consistently related to a single factor. Handwriting difficulties are common in children with ADHD, and medication alone is not sufficient to resolve these challenges. © 2012 SAGE Publications.
Simos, Panagiotis G.; Rezaie, Roozbeh; Papanicolaou, Andrew C.; Fletcher, Jack M.
2014-01-01
The study examined whether individual differences in performance and verbal IQ affect the profiles of reading-related regional brain activation in 127 students experiencing reading difficulties and typical readers. Using magnetoencephalography in a pseudoword read-aloud task, we compared brain activation profiles of students experiencing word-level reading difficulties who did (n = 29) or did not (n = 36) meet the IQ-reading achievement discrepancy criterion. Typical readers assigned to a lower-IQ (n = 18) or a higher IQ (n = 44) subgroup served as controls. Minimum norm estimates of regional cortical activity revealed that the degree of hypoactivation in the left superior temporal and supramarginal gyri in both RD subgroups was not affected by IQ. Moreover, IQ did not moderate the positive association between degree of activation in the left fusiform gyrus and phonological decoding ability. We did find, however, that the hypoactivation of the left pars opercularis in RD was restricted to lower-IQ participants. In accordance with previous morphometric and fMRI studies, degree of activity in inferior frontal, and inferior parietal regions correlated with IQ across reading ability subgroups. Results are consistent with current views questioning the relevance of IQ-discrepancy criteria in the diagnosis of dyslexia. PMID:24409136
Simos, Panagiotis G; Rezaie, Roozbeh; Papanicolaou, Andrew C; Fletcher, Jack M
2014-01-01
The study examined whether individual differences in performance and verbal IQ affect the profiles of reading-related regional brain activation in 127 students experiencing reading difficulties and typical readers. Using magnetoencephalography in a pseudoword read-aloud task, we compared brain activation profiles of students experiencing word-level reading difficulties who did (n = 29) or did not (n = 36) meet the IQ-reading achievement discrepancy criterion. Typical readers assigned to a lower-IQ (n = 18) or a higher IQ (n = 44) subgroup served as controls. Minimum norm estimates of regional cortical activity revealed that the degree of hypoactivation in the left superior temporal and supramarginal gyri in both RD subgroups was not affected by IQ. Moreover, IQ did not moderate the positive association between degree of activation in the left fusiform gyrus and phonological decoding ability. We did find, however, that the hypoactivation of the left pars opercularis in RD was restricted to lower-IQ participants. In accordance with previous morphometric and fMRI studies, degree of activity in inferior frontal, and inferior parietal regions correlated with IQ across reading ability subgroups. Results are consistent with current views questioning the relevance of IQ-discrepancy criteria in the diagnosis of dyslexia.
Developing and assessing research-based tools for teaching quantum mechanics and thermodynamics
NASA Astrophysics Data System (ADS)
Brown, Benjamin R.
Research-based tools to educate college students in physics courses from introductory level to graduate level are essential for helping students with a diverse set of goals and backgrounds learn physics. This thesis explores issues related to student common difficulties with some topics in undergraduate quantum mechanics and thermodynamics courses. Student difficulties in learning quantum mechanics and thermodynamics are investigated by administering written tests and surveys to many classes and conducting individual interviews with a subset of students outside the class to unpack the cognitive mechanisms of the difficulties. The quantum mechanics research also focuses on using the research on student difficulties for the development and evaluation of a Quantum Interactive Learning Tutorial (QuILT) to help students learn about the time-dependence of expectation values using the context of Larmor precession of spin and evaluating the role of asking students to self-diagnose their mistakes on midterm examination on their performance on subsequent problem solving. The QuILT on Larmor precession of spin has both paper-pencil activities and a simulation component to help students learn these foundational issues in quantum mechanics. Preliminary evaluations suggest that the QuILT, which strives to help students build a robust knowledge structure of time-dependence of expectation values in quantum mechanics using a guided approach, is successful in helping students learn these topics in the junior-senior level quantum mechanics courses. The technique to help upper-level students in quantum mechanics courses effectively engage in the process of learning from their mistakes is also found to be effective. In particular, research shows that the self-diagnosis activity in upper-level quantum mechanics significantly helps students who are struggling and this activity can reduce the gap between the high and low achieving students on subsequent problem solving. Finally, a survey of Thermodynamic Processes and the First and Second Laws (STPFaSL) is developed and validated with the purpose of evaluating the effectiveness of these topics in a thermodynamics curriculum. The validity and reliability of this survey are discussed and the student difficulties with these topics among various groups from introductory students to physics graduate students are cataloged.
Prescription Birth Control Access Among U.S. Women at Risk of Unintended Pregnancy.
Grindlay, Kate; Grossman, Daniel
2016-03-01
Access to contraception is a vital component of preventing unintended pregnancies. This study was conducted to assess the prevalence of and factors associated with U.S. women's difficulty accessing prescription contraception (pill, patch, or ring). We performed a nationally representative survey of adult women at risk of unintended pregnancy (aged 18-44, not pregnant or seeking pregnancy, sexually active, not sterilized) using a probability-based web panel. In November to December 2011, 2046 women completed the survey. Weighted proportions were calculated and logistic regression was used to identify covariates associated with difficulty obtaining or refilling prescription contraception. A total of 1385 (68%) women had ever tried to get a prescription for hormonal contraception. Among this population, 29% reported ever having problems obtaining a prescription or refills. In multivariable regression, uninsured (vs. privately insured) and Spanish-speaking (vs. English-speaking) women were significantly more likely to report difficulties; women with a high school degree and those with some college (vs. a college degree or higher) were significantly less likely to report difficulty. Difficulties included cost barriers or lack of insurance (14%), challenges obtaining an appointment or getting to a clinic (13%), the clinician requiring a clinic visit, exam, or Pap smear (13%), not having a regular doctor/clinic (10%), difficulty accessing a pharmacy (4%), and other reasons (4%). One-third of adult U.S. women who have ever tried to obtain prescription contraception reported access barriers. While the Affordable Care Act may resolve some of these issues, these data indicate that additional factors may still need to be addressed.
Attention in a multi-task environment
NASA Technical Reports Server (NTRS)
Andre, Anthony D.; Heers, Susan T.
1993-01-01
Two experiments used a low fidelity multi-task simulation to investigate the effects of cue specificity on task preparation and performance. Subjects performed a continuous compensatory tracking task and were periodically prompted to perform one of several concurrent secondary tasks. The results provide strong evidence that subjects enacted a strategy to actively divert resources towards secondary task preparation only when they had specific information about an upcoming task to be performed. However, this strategy was not as much affected by the type of task cued (Experiment 1) or its difficulty level (Experiment 2). Overall, subjects seemed aware of both the costs (degraded primary task tracking) and benefits (improved secondary task performance) of cue information. Implications of the present results for computational human performance/workload models are discussed.
Lithfous, Ségolène; Tromp, Delphine; Dufour, André; Pebayle, Thierry; Goutagny, Romain; Després, Olivier
2015-10-01
The purpose of this study was to investigate the role of theta activity in cognitive mapping, and to determine whether age-associated decreased theta power may account for navigational difficulties in elderly individuals. Cerebral activity was recorded using electroencephalograph in young and older individuals performing a spatial memory task that required the creation of cognitive maps. Power spectra were computed in the frontal and parietal regions and correlated with recognition performance. We found that accuracy of cognitive mapping was positively correlated with left frontal theta activity during encoding in young adults but not in older individuals. Compared with young adults, older participants were impaired in the creation of cognitive maps and showed reduced theta and alpha activity at encoding. These results suggest that encoding processes are impaired in older individual, which may explain age-related cognitive mapping deficits. Copyright © 2015 Elsevier Inc. All rights reserved.
Longitudinal changes in everyday life after home modifications for people aging with disabilities.
Petersson, Ingela; Kottorp, Anders; Bergström, Jakob; Lilja, Margareta
2009-05-01
To investigate longitudinal impacts of home modifications on the difficulty of performing everyday life tasks for people aging with disabilities, and to investigate whether other factors had any additional impacts on difficulty in everyday life tasks for people receiving home modifications. The sample consisted of 103 persons aging with disabilities and in need of home modifications, divided into an intervention group and a comparison group. The data were first subjected to Rasch analysis and a random coefficient model was used. Participants in the intervention group reported a significantly lower level of difficulty in everyday life tasks compared with those in the comparison group. One confounding factor, number of months waiting for home modification, had an impact on difficulty in everyday life. Home modifications are effective in decreasing difficulty in performing everyday life tasks up to six months after the installation. Furthermore, to be effective home modifications need to be installed in a timely fashion. For each consecutive month the person waited for their home modification the difficulty of performing everyday life tasks increased. Therefore, it is important that home modifications be installed as soon as possible after the need has been identified.
NASA Astrophysics Data System (ADS)
Sayer, Ryan; Marshman, Emily; Singh, Chandralekha
2016-12-01
Just-in-Time Teaching (JiTT) is an instructional strategy involving feedback from students on prelecture activities in order to design in-class activities to build on the continuing feedback from students. We investigate the effectiveness of a JiTT approach, which included in-class concept tests using clickers in an upper-division quantum mechanics course. We analyze student performance on prelecture reading quizzes, in-class clicker questions answered individually, and clicker questions answered after group discussion, and compare those performances with open-ended retention quizzes administered after all instructional activities on the same concepts. In general, compared to the reading quizzes, student performance improved when individual clicker questions were posed after lectures that focused on student difficulties found via electronic feedback. The performance on the clicker questions after group discussion following individual clicker question responses also showed improvement. We discuss some possible reasons for the improved performance at various stages, e.g., from prelecture reading quizzes to postlecture clicker questions, and from individual to group clicker questions.
Performance of activities of daily living among hospitalized cancer patients.
Lindahl-Jacobsen, Line; Hansen, Dorte Gilså; Wæhrens, Eva Ejlersen; la Cour, Karen; Søndergaard, Jens
2015-03-01
Many cancer patients report unmet rehabilitation needs. Rehabilitation may include activities of daily living (ADL) tasks, but little is known about how cancer patients perform these tasks and how they prioritize their daily activities. Hence, this study aims to identify and characterize ADL task performance problems among a group of adult disabled hospitalized cancer patients using interview and questionnaire data. Cross-sectional study on prevalence of ADL task performance problems experienced by disabled hospitalized cancer patients using the Activities of Daily Living Questionnaire (ADL-Q) (n = 118) and the Canadian Occupational Performance Measure (COPM) (n = 55). All 118 patients reported problems with ADL task performance. Based on the ADL-Q patients reported more problems within instrumental (I-)ADL than personal (P-)ADL. In both I-ADL and P-ADL the results differed between women and men. There was significant overlap between problems identified using the COPM and the ADL-Q instruments. RESULTS from the COPM showed that 65% of problems were related to self-care, 25% to leisure, and 19% to productivity. Using both instruments identified more ADL problems than when using only one of the instruments. Adult hospitalized disabled cancer patients experience a high degree and variation in difficulties performing ADL, illustrating the need for a comprehensively planned assessment of problems and needs.
ERIC Educational Resources Information Center
Bryant, Brian R.; Bryant, Diane Pedrotty; Porterfield, Jennifer; Dennis, Minyi Shih; Falcomata, Terry; Valentine, Courtney; Brewer, Chelsea; Bell, Kathy
2016-01-01
The purpose of this study was to determine the effectiveness of a systematic, explicit, intensive Tier 3 (tertiary) intervention on the mathematics performance of students in second grade with severe mathematics difficulties. A multiple-baseline design across groups of participants showed improved mathematics performance on number and operations…
Schoemaker, Marina M; Lingam, Raghu; Jongmans, Marian J; van Heuvelen, Marieke J G; Emond, Alan
2013-10-01
Aim of the study was to investigate whether 7-9 year old children with severe motor difficulties are more at risk of additional difficulties in activities in daily living, academic skills, attention and social skills than children with moderate motor difficulties. Children (N=6959) from a population based cohort, the Avon Longitudinal Study of Parents and Children (ALSPAC), were divided into three groups based on their scores on the ALSPAC Coordination Test at age 7: control children (scores above 15th centile; N=5719 [82.1%]); children with moderate (between 5th and 15th centile; N=951 [13.7%]); and children with severe motor difficulties (below 5th centile N=289 [4.2%]). Children with neurological disorders or an IQ<70 were excluded. Logistic regression was used to compare children with moderate and severe motor coordination difficulties with each other and with control children regarding their risk of co-morbidity defined as significant (<10th centile) difficulties with activities of daily living (ADL); academic skills (reading, spelling and handwriting); attention; social skills (social cognition and nonverbal skills). Children with severe motor difficulties demonstrated a higher risk of difficulties in ADL, handwriting, attention, reading, and social cognition than children with moderate motor difficulties, who in turn had a higher risk of difficulties than control children in five out of seven domains. Screening and intervention of co-morbid problems is recommended for children with both moderate and severe motor difficulties. Copyright © 2013. Published by Elsevier Ltd.
Endoscopic approaches to pituitary lesions: difficulties and challenges.
de los Santos, Gonzalo; Fragola, Claudio; Del Castillo, Raúl; Rodríguez, Víctor; D'oleo, Claudio; Reyes, Pablo
2013-01-01
The evolution of surgical approaches to the pituitary region brings benefits to the patient, but also means changes for otolaryngologists, who have to face new difficulties and complications. The objective of this paper was to present our experience in the endoscopic approach to the pituitary region, assessing the difficulties and complications encountered, and to offer possible elements for improvement. We reviewed the first 40 cases of pituitary approaches we carried out between 2008 and 2011. Interventions were performed by a team of neurosurgeons and otolaryngologists in simultaneous collaboration. We analysed the pathology intervened, complications and difficulties. There were 37 patients operated on for pituitary tumours and 3 cysts; 34 cases were macroadenomas. The complications were 6 cerebrospinal fluid leaks, 3 with meningitis, 6 diabetes insipidus, 1 pulmonary embolism, 1 hydrocephalus and 4 mild nasal complications. The frequency and type of complications depend on the extent of the endoscopic approach, patient age, tumour size and suprasellar extension. The use of specific instruments, navigation and preoperative assessment of imaging tests help to minimise complications. Prudent implementation of new approaches, knowledge of techniques and complications, and the analysis of the activity allow further progress in access to skull base pathology. Copyright © 2012 Elsevier España, S.L. All rights reserved.
Heitger, Marcus H.; Goble, Daniel J.; Dhollander, Thijs; Dupont, Patrick; Caeyenberghs, Karen; Leemans, Alexander; Sunaert, Stefan; Swinnen, Stephan P.
2013-01-01
In bimanual coordination, older and younger adults activate a common cerebral network but the elderly also have additional activation in a secondary network of brain areas to master task performance. It remains unclear whether the functional connectivity within these primary and secondary motor networks differs between the old and the young and whether task difficulty modulates connectivity. We applied graph-theoretical network analysis (GTNA) to task-driven fMRI data in 16 elderly and 16 young participants using a bimanual coordination task including in-phase and anti-phase flexion/extension wrist movements. Network nodes for the GTNA comprised task-relevant brain areas as defined by fMRI activation foci. The elderly matched the motor performance of the young but showed an increased functional connectivity in both networks across a wide range of connectivity metrics, i.e., higher mean connectivity degree, connection strength, network density and efficiency, together with shorter mean communication path length between the network nodes and also a lower betweenness centrality. More difficult movements showed an increased connectivity in both groups. The network connectivity of both groups had “small world” character. The present findings indicate (a) that bimanual coordination in the aging brain is associated with a higher functional connectivity even between areas also activated in young adults, independently from task difficulty, and (b) that adequate motor coordination in the context of task-driven bimanual control in older adults may not be solely due to additional neural recruitment but also to aging-related changes of functional relationships between brain regions. PMID:23637982
Specificity of postural sway to the demands of a precision task at sea.
Chen, Fu-Chen; Stoffregen, Thomas A
2012-06-01
Mariners actively adjust their body orientation in response to ship motion. On a ship at sea, we evaluated relations between standing postural activity and the performance of a precision aiming task. Standing participants (experienced mariners) maintained the beam from a handheld laser on a target. Targets were large or small, thereby varying the difficulty of the aiming task. Targets were located in front of the participant or to the participant's right (requiring participants to look over the right shoulder), thereby varying the functional consequences (for the aiming task) of postural activity in different body axes. The torso was oriented toward the bow or toward the ship's side (athwartship), thereby varying the effects on postural activity of differential motion of the ship in its different axes. The weather was rough, producing high magnitudes of ship motion, which sometimes caused participants to step or stagger. Our manipulations influenced the magnitude and dynamics of head and torso movements, as well as the organization of movement in different axes. The results provide the first empirical confirmation that postural activity can be influenced by orientation of the torso relative to a ship. Despite powerful effects of ship motion, postural activity was influenced by variations in target location and in the difficulty of the aiming task, replicating subtle effects that have been observed on land. We discuss implications for hull design and the placement of workstations on ships.
Theeven, Patrick; Hemmen, Bea; Rings, Frans; Meys, Guido; Brink, Peter; Smeets, Rob; Seelen, Henk
2011-10-01
To assess the effects of using a microprocessor-controlled prosthetic knee joint on the functional performance of activities of daily living in persons with an above-knee leg amputation. To assess the effects of using a microprocessor-controlled prosthetic knee joint on the functional performance of activities of daily living in persons with an above-knee leg amputation. Randomised cross-over trial. Forty-one persons with unilateral above-knee or knee disarticulation limb loss, classified as Medicare Functional Classification Level-2 (MFCL-2). Participants were measured in 3 conditions, i.e. using a mechanically controlled knee joint and two types of microprocessor-controlled prosthetic knee joints. Functional performance level was assessed using a test in which participants performed 17 simulated activities of daily living (Assessment of Daily Activity Performance in Transfemoral amputees test). Performance time was measured and self-perceived level of difficulty was scored on a visual analogue scale for each activity. High levels of within-group variability in functional performance obscured detection of any effects of using a microprocessor-controlled prosthetic knee joint. Data analysis after stratification of the participants into 3 subgroups, i.e. participants with a "low", "intermediate" and "high" functional mobility level, showed that the two higher functional subgroups performed significantly faster using microprocessor-controlled prosthetic knee joints. MFCL-2 amputees constitute a heterogeneous patient group with large variation in functional performance levels. A substantial part of this group seems to benefit from using a microprocessor-controlled prosthetic knee joint when performing activities of daily living.
Learning Setting-Generalized Activity Models for Smart Spaces
Cook, Diane J.
2011-01-01
The data mining and pervasive computing technologies found in smart homes offer unprecedented opportunities for providing context-aware services, including health monitoring and assistance to individuals experiencing difficulties living independently at home. In order to provide these services, smart environment algorithms need to recognize and track activities that people normally perform as part of their daily routines. However, activity recognition has typically involved gathering and labeling large amounts of data in each setting to learn a model for activities in that setting. We hypothesize that generalized models can be learned for common activities that span multiple environment settings and resident types. We describe our approach to learning these models and demonstrate the approach using eleven CASAS datasets collected in seven environments. PMID:21461133
Thakral, Manu; Shi, Ling; Foust, Janice B; Patel, Kushang V; Shmerling, Robert H; Bean, Jonathan F; Leveille, Suzanne G
2018-06-18
This study aims to test whether persistent pain quality is associated with incident or worsening disability in four domains: mobility, ADL and IADL difficulty and physical performance. From the MOBILIZE Boston Study, a population-based cohort of adults aged ≥70 years, we studied participants with chronic pain who endorsed at least one pain quality descriptor (N=398) and completed baseline and 18-month assessments. Pain quality was assessed using an adapted short-form McGill Pain Questionnaire with 20 pain quality descriptors in 3 categories: sensory, cognitive/affective, neuropathic. Persistence was defined as endorsing the same category at baseline and 18 months. Self-reported outcomes included mobility, ADL, and IADL difficulty. Physical performance was assessed using the Short Physical Performance Battery. After adjusting for baseline pain severity and other covariates, individuals with 3 persistent categories had a greater risk of developing new or worsening IADL difficulty relative to those with 1 persistent category (RR 2.69, 95% CI 1.34, 7.79). Similar results were observed for ADL difficulty (RR 5.83, 95% CI 1.32, 25.85) but no differences were noted in risk for mobility difficulty. There was no significant linear trend in physical performance over 18 months according to number of persistent categories (p=0.68). Elders with persistent pain quality experienced a higher risk of developing new or worsening IADL and ADL disability with each additional category but not mobility difficulty or poorer physical performance. Longitudinal assessment of pain quality could be useful in determining risk for global disability among elders with chronic pain.
Vogel, Tobias; Genschow, Oliver
2013-04-01
Research on regulatory focus theory (Higgins, 1997) suggests that performance increases if instructions fit with sportspersons' dispositions. Sportspersons who chronically focus on wins (i.e., promotion-oriented individuals) perform best if instructions frame the objective as a promotion goal (e.g., "Try to hit!"). By contrast, sportspersons who chronically focus on losses (i.e., prevention-oriented individuals) perform best if instructions frame the objective as a prevention goal (e.g., "Try not to miss!"). Recent theorizing also suggests that regulatory focus interacts with task difficulty. In an experiment, we assessed soccer performance as a function of chronic focus, instructional focus, and task difficulty. Results support that task difficulty moderates the effects of fit on performance; fitting instructions to match the sportsperson's chronic regulatory focus improved performance in the easy rather than the difficult task. Findings are discussed regarding the role of regulatory fit in altering subjective pressure during sports performance.
Cognition in school-aged children with "active" epilepsy: A population-based study.
Reilly, Colin; Atkinson, Patricia; Das, Krishna B; Chin, Richard F M; Aylett, Sarah E; Burch, Victoria; Gillberg, Christopher; Scott, Rod C; Neville, Brian G R
2015-01-01
There is a lack of population-based data on specific cognitive profiles in childhood epilepsy. This study sought to determine the frequency of impairments in global cognition and aspects of working memory and processing speed in a population-based sample of children with "active" epilepsy (on antiepileptic Drugs (AEDs), and/or had a seizure in the last year). Factors significantly associated with global and specific difficulties in cognition were also identified. A total of 85 (74% of eligible population) school-aged children (5-15 years) with "active" epilepsy underwent comprehensive psychological assessment including assessment of global cognition, working memory, and processing speed. Scores on cognitive subtests were compared via paired-samples t tests. The factors associated with cognitive difficulties were analyzed via linear regression. A total of 24% of children were functioning below IQ 50, and 40% had IQ scores below 70. Scores on the Processing Speed Index were significantly lower than scores on the Verbal or Performance indexes on Wechsler instruments. The Coding subtest was a significant weakness compared with the other Wechsler subtests. A total of 58% of children displayed "memory underachievement" (memory score 1 SD below assessed IQ) on at least one of the four administered working memory subtests. Factors significantly associated with globally impaired cognition included being on polytherapy (β = -13.0; 95% CI [-19.3, -6.6], p = .000) and having attention-deficit/hyperactivity disorder (ADHD; β = -11.1, 95% CI [-3.0, -19.3], p = .008). Being on polytherapy was also associated with lower scores on the working memory and processing speed composite scores. Having developmental coordination disorder (DCD) was associated with a lower score on the processing speed composite. There is a high rate of global and specific cognitive difficulties in childhood epilepsy. Difficulties are most pronounced in aspects of working memory and processing speed. Predictors of cognitive impairment in childhood epilepsy include epilepsy-related and behavioral factors, which may differ depending on the domain of cognition assessed.
Taha, Haitham
2017-01-01
Executive functions (EFs) measures of 27 asthmatic children, with general learning difficulties, were tested by using the Wisconsin card sorting test (WCST), and were compared to the performances of 30 non-asthmatic children with general learning difficulties. The results revealed that the asthmatic group has poor performance through all the WCST psychometric parameters and especially the perseverative errors one. The results were discussed in light of the postulation that poor EFs could be associated with the learning difficulties of asthmatic children. Neurophysiological framework has been suggested to explain the etiology of poor EFs among children with moderate into severe asthma.
Volz-Sidiropoulou, Eftychia; Gauggel, Siegfried
2012-06-01
Older individuals who recognize their cognitive difficulties are more likely to adjust their everyday life to their actual cognitive functioning, particularly when they are able to estimate their abilities accurately. We assessed self- and spouse-ratings of memory and attention difficulties in everyday life of healthy, older individuals and compared them with the respective test performance. Eighty-four older individuals (women's age, M = 67.4 years, SD = 5.2; men's age, M = 68.5 years, SD = 4.9) completed both the self and the spouse versions of the Attention Deficit Questionnaire and the Everyday Memory Questionnaire and completed two neuropsychological tests. Using the residual score approach, subjective metacognitive measures of memory and attention were created and compared with actual test performance. Significant associations between subjective and objective scores were found only for men and only for episodic memory measures. Men who underreported memory difficulties performed more poorly; men who overreported memory difficulties performed better. Men's recognition performance was best predicted by subjective measures (R² = .25), followed by delayed recall (R² = .14) and forgetting rate (R² = .13). The results indicate gender-specific differences in metacognitive accuracy and predictive validity of subjective ratings. PsycINFO Database Record (c) 2012 APA, all rights reserved
Prediction and Stability of Mathematics Skill and Difficulty
Martin, Rebecca B.; Cirino, Paul T.; Barnes, Marcia A.; Ewing-Cobbs, Linda; Fuchs, Lynn S.; Stuebing, Karla K.; Fletcher, Jack M.
2016-01-01
The present study evaluated the stability of math learning difficulties over a 2-year period and investigated several factors that might influence this stability (categorical vs. continuous change, liberal vs. conservative cut point, broad vs. specific math assessment); the prediction of math performance over time and by performance level was also evaluated. Participants were 144 students initially identified as having a math difficulty (MD) or no learning difficulty according to low achievement criteria in the spring of Grade 3 or Grade 4. Students were reassessed 2 years later. For both measure types, a similar proportion of students changed whether assessed categorically or continuously. However, categorical change was heavily dependent on distance from the cut point and so more common for MD, who started closer to the cut point; reliable change index change was more similar across groups. There were few differences with regard to severity level of MD on continuous metrics or in terms of prediction. Final math performance on a broad computation measure was predicted by behavioral inattention and working memory while considering initial performance; for a specific fluency measure, working memory was not uniquely related, and behavioral inattention more variably related to final performance, again while considering initial performance. PMID:22392890
Prediction and stability of mathematics skill and difficulty.
Martin, Rebecca B; Cirino, Paul T; Barnes, Marcia A; Ewing-Cobbs, Linda; Fuchs, Lynn S; Stuebing, Karla K; Fletcher, Jack M
2013-01-01
The present study evaluated the stability of math learning difficulties over a 2-year period and investigated several factors that might influence this stability (categorical vs. continuous change, liberal vs. conservative cut point, broad vs. specific math assessment); the prediction of math performance over time and by performance level was also evaluated. Participants were 144 students initially identified as having a math difficulty (MD) or no learning difficulty according to low achievement criteria in the spring of Grade 3 or Grade 4. Students were reassessed 2 years later. For both measure types, a similar proportion of students changed whether assessed categorically or continuously. However, categorical change was heavily dependent on distance from the cut point and so more common for MD, who started closer to the cut point; reliable change index change was more similar across groups. There were few differences with regard to severity level of MD on continuous metrics or in terms of prediction. Final math performance on a broad computation measure was predicted by behavioral inattention and working memory while considering initial performance; for a specific fluency measure, working memory was not uniquely related, and behavioral inattention more variably related to final performance, again while considering initial performance.
Geary, Phillip; Lucas, Steven
2018-02-03
Aquaculture in many coastal estuaries is threatened by diffuse sources of runoff from different land use activities. The poor performance of septic tank systems (STS), as well as runoff from agriculture, may contribute to the movement of contaminants through ground and surface waters to estuaries resulting in oyster contamination, and following their consumption, impacts to human health. In monitoring individual STS in sensitive locations, it is possible to show that nutrients and faecal contaminants are transported through the subsurface in sandy soils off-site with little attenuation. At the catchment scale however, there are always difficulties in discerning direct linkages between failing STS and water contamination due to processes such as effluent dilution, adsorption, precipitation and vegetative uptake. There is often substantial complexity in detecting and tracing effluent pathways from diffuse sources to water bodies in field studies. While source tracking as well as monitoring using tracers may assist in identifying potential pathways from STS to surface waters and estuaries, there are difficulties in scaling up from monitored individual systems to identify their contribution to the cumulative impact which may be apparent at the catchment scale. The processes which may be obvious through monitoring and dominate at the individual scale may be masked and not readily discernible at the catchment scale due to impacts from other land use activities.
Portellano-Ortiz, Cristina; Garre-Olmo, Josep; Calvó-Perxas, Laia; Conde-Sala, Josep Lluís
2017-08-31
The aims of this study are: to analyze the factor structure of the EURO-D depression scale; to explore the variables associated with depressive symptoms in the total sample and in the EURO-D factors; and to compare the presence of depressive symptoms and the factor distribution in 15 European countries. 62,182 participants in Wave 5 (2013) of the Survey of Health, Aging and Retirement in Europe (SHARE) were included. The SHARE study and the EURO-D scale. Factor, bivariate and multilevel analyses were performed. Higher levels of depressive symptoms were associated with a poorer self-perception of physical health (η 2 = 0.22) and economic difficulties (η 2 = 0.07). Factor analysis of the EURO-D identified two factors: Suffering and Motivation. Higher levels of depressive symptoms were associated with female gender and younger age (≤60) in the Suffering factor, and with less activity and exercise, older age (≥71), widowhood and lower educational level in the Motivation factor. Poorer self-perception of physical health and economic difficulties were associated with higher depressive symptomatology in both factors. Poorer self-perception of physical health, female gender, economic difficulties, widowhood, lower levels of activity and exercise and lower educational level were associated with higher depressive symptomatology. In the countries of southern Europe, the Motivation factor predominated.
Association Between Executive Function and Problematic Adolescent Driving.
Pope, Caitlin N; Ross, Lesley A; Stavrinos, Despina
Motor vehicle collisions (MVCs) are one of the leading causes of injury and death for adolescents. Driving is a complex activity that is highly reliant on executive function (EF) to safely navigate through the environment. Little research has examined the efficacy of using self-reported EF measures for assessing adolescent driving risk. This study examined the Behavior Rating Inventory of Executive Function (BRIEF) questionnaire and performance-based EF tasks as potential predictors of problematic driving outcomes in adolescents. Forty-six adolescent drivers completed the (1) BRIEF, (2) Trail Making Test, (3) Backwards Digit Span, and (4) self-report on 3 problematic driving outcomes: the number of times of having been pulled over by a police officer, the number of tickets issued, and the number of MVCs. Greater self-reported difficulty with planning and organization was associated with greater odds of having a MVC, whereas inhibition difficulties were associated with greater odds of receiving a ticket. Greater self-reported difficulty across multiple BRIEF subscales was associated with greater odds of being pulled over. Overall findings indicated that the BRIEF, an ecological measure of EF, showed significant association with self-reported problematic driving outcomes in adolescents. No relationship was found between performance-based EF measures and self-reported driving outcomes. The BRIEF could offer unique and quick insight into problematic driving behavior and potentially be an indicator of driving risk in adolescent drivers during clinical evaluations.
Predictive factors of difficulty in lower third molar extraction: A prospective cohort study
Alvira-González, Joaquín; Valmaseda-Castellón, Eduard; Quesada-Gómez, Carmen; Gay-Escoda, Cosme
2017-01-01
Background Several publications have measured the difficulty of third molar removal, trying to establish the main risk factors, however several important preoperative and intraoperative variables are overlooked. Material and Methods A prospective cohort study comprising a total of 130 consecutive lower third molar extractions was performed. The outcome variables used to measure the difficulty of the extraction were operation time and a 100mm visual analogue scale filled by the surgeon at the end of the surgical procedure. The predictors were divided into 4 different groups (demographic, anatomic, radiographic and operative variables). A descriptive, bivariate and multivariate analysis of the data was performed. Results Patients’ weight, the presence of bulbous roots, the need to perform crown and root sectioning of the lower third molar and Pell and Gregory 123 classification significantly influenced both outcome variables (p< 0.05). Conclusions Certain anatomical, radiological and operative variables appear to be important factors in the assessment of surgical difficulty in the extraction of lower third molars. Key words:Third molar, surgical extraction, surgical difficulty. PMID:27918736
Stress and burden among caregivers of patients with Lewy body dementia.
Leggett, Amanda N; Zarit, Steven; Taylor, Angela; Galvin, James E
2011-02-01
Patients with Lewy body dementia (LBD) may present a unique set of symptoms and challenges to family caregivers compared with other types of dementia. Prominent difficulties include motor impairment, activities of daily living (ADLs) disability, recurrent behavioral and emotional problems (BEPs), and diagnostic difficulties. These problems are likely to affect caregivers' subjective burden. The present study used data from an Internet survey conducted by the Lewy Body Dementia Association. Respondents were 611 people who indicated that they were currently involved in the care of their relative with LBD. Subjective burden was assessed with a 12-item short version of the Zarit Burden Interview. A factor analysis revealed 3 dimensions of burden: role strain, personal strain, and worry about performance. Multiple regressions were used to examine predictors of these dimensions. BEPs, ADL disability, isolation, caregiver age, and patient gender were significant predictors of specific factors. Falls, formal service use, difficulty finding a physician, and evaluation of the physician had no significant associations with burden. These findings highlight burden experiences by caregivers of patients with LBD and the impact of BEPs, ADL assistance, and awareness about LBD on subjective burden.
Role of Process Control in Improving Space Vehicle Safety A Space Shuttle External Tank Example
NASA Technical Reports Server (NTRS)
Safie, Fayssal M.; Nguyen, Son C.; Burleson, Keith W.
2006-01-01
Developing a safe and reliable space vehicle requires good design and good manufacturing, or in other words "design it right and build it right". A great design can be hard to build or manufacture mainly due to difficulties related to quality. Specifically, process control can be a challenge. As a result, the system suffers from low quality which leads to low reliability and high system risk. The Space Shuttle has experienced some of those cases, but has overcome these difficulties through extensive redesign efforts and process enhancements. One example is the design of the hot gas temperature sensor on the Space Shuttle Main Engine (SSME), which resulted in failure of the sensor in flight and led to a redesign of the sensor. The most recent example is the Space Shuttle External Tank (ET) Thermal Protection System (TPS) reliability issues that contributed to the Columbia accident. As a result, extensive redesign and process enhancement activities have been performed over the last two years to minimize the sensitivities and difficulties of the manual TPS application process.
TELEGRAM: contribution in assistive technology indication for individuals with hearing impairment.
Jacob, Regina Tangerino de Souza; Lopes, Natália Barreto Frederigue; Cruz, Aline Duarte da; Alves, Tacianne Kriscia Machado; Santos, Larissa Germiniani Dos; Angelo, Thais Corina Said de; Mondelli, Maria Fernanda Capoani Garcia; Moret, Adriane Lima Mortari
2017-02-23
The objective of the study was to translate and culturally adapt to Portuguese the TELEGRAM instrument and to evaluate its effectiveness in adults with hearing impairment using hearing aids. The TELEGRAM was translated into the Portuguese language, reviewed for grammatical and idiomatic equivalences (reverse translations) and linguistic and cultural adaptations. After translation, the TELEGRAM was applied to 20 individuals with hearing impairment. A descriptive analysis of the results was performed. After the grammatical and idiomatic equivalence, the replacement of one term/item was suggested, which was modified and adapted to the Brazilian context. In general, the questions of the instrument were considered easy to understand. Among the categories assessed, individuals with hearing loss had greater difficulty using the telephone and in activities such as attending church gatherings, parties, or in situations of noisy environments, distance and reverberation. The TELEGRAM translated into Brazilian Portuguese proved to be an easily applicable tool in population studies and effective to assess which are the main situations where individuals with hearing impairment have greater difficulty in communication, reinforcing the importance of hearing rehabilitation and assistive technology to minimize these difficulties.
Waites, Anthony B; Mannfolk, Peter; Shaw, Marnie E; Olsrud, Johan; Jackson, Graeme D
2007-02-01
Clinical functional magnetic resonance imaging (fMRI) occasionally fails to detect significant activation, often due to variability in task performance. The present study seeks to test whether a more flexible statistical analysis can better detect activation, by accounting for variance associated with variable compliance to the task over time. Experimental results and simulated data both confirm that even at 80% compliance to the task, such a flexible model outperforms standard statistical analysis when assessed using the extent of activation (experimental data), goodness of fit (experimental data), and area under the operator characteristic curve (simulated data). Furthermore, retrospective examination of 14 clinical fMRI examinations reveals that in patients where the standard statistical approach yields activation, there is a measurable gain in model performance in adopting the flexible statistical model, with little or no penalty in lost sensitivity. This indicates that a flexible model should be considered, particularly for clinical patients who may have difficulty complying fully with the study task.
Pereira, Michael; Argelaguet, Ferran; Millán, José Del R; Lécuyer, Anatole
2018-01-01
Competition changes the environment for athletes. The difficulty of training for such stressful events can lead to the well-known effect of "choking" under pressure, which prevents athletes from performing at their best level. To study the effect of competition on the human brain, we recorded pilot electroencephalography (EEG) data while novice shooters were immersed in a realistic virtual environment representing a shooting range. We found a differential between-subject effect of competition on mu (8-12 Hz) oscillatory activity during aiming; compared to training, the more the subject was able to desynchronize his mu rhythm during competition, the better was his shooting performance. Because this differential effect could not be explained by differences in simple measures of the kinematics and muscular activity, nor by the effect of competition or shooting performance per se , we interpret our results as evidence that mu desynchronization has a positive effect on performance during competition.
Pereira, Michael; Argelaguet, Ferran; Millán, José del R.; Lécuyer, Anatole
2018-01-01
Competition changes the environment for athletes. The difficulty of training for such stressful events can lead to the well-known effect of “choking” under pressure, which prevents athletes from performing at their best level. To study the effect of competition on the human brain, we recorded pilot electroencephalography (EEG) data while novice shooters were immersed in a realistic virtual environment representing a shooting range. We found a differential between-subject effect of competition on mu (8–12 Hz) oscillatory activity during aiming; compared to training, the more the subject was able to desynchronize his mu rhythm during competition, the better was his shooting performance. Because this differential effect could not be explained by differences in simple measures of the kinematics and muscular activity, nor by the effect of competition or shooting performance per se, we interpret our results as evidence that mu desynchronization has a positive effect on performance during competition.
Zafeiriou, Athina; Gendolla, Guido H E
2017-09-01
Based on previous research on implicit effects on effort-related cardiovascular response and evidence that aging is associated with cognitive difficulties, we tested whether the mere activation of the aging stereotype can systematically influence young individuals' effort-mobilization during cognitive performance. Young participants performed an objectively difficult short-term memory task during which they processed elderly vs. youth primes and expected low vs. high incentive for success. When participants processed elderly primes during the task, we expected cardiovascular response to be weak in the low-incentive condition and strong in the high-incentive condition. Unaffected by incentive, effort in the youth-prime condition should fall in between the two elderly-prime cells. Effects on cardiac pre-ejection period (PEP) and heart rate (HR) largely supported these predictions. The present findings show for the first time that the mere activation of the aging stereotype can systematically influence effort mobilization during cognitive performance-even in young adults. Copyright © 2017 Elsevier B.V. All rights reserved.
Bustillo-Casero, Pilar; Villarrasa-Sapiña, Israel; García-Massó, Xavier
2017-10-01
In the present study our aim was to compare dual-task performance in thirteen adolescents and fifteen young adults while concurrently performing a cognitive and a motor task. The postural control variables were obtained under three different conditions: i) bipedal stance, ii) tandem stance and iii) unipedal stance. The cognitive task consisted of a backward digit span test in which the participants were asked to memorize a sequence of numbers and then repeat the number in reverse order at three different difficulty levels (i.e. with 3, 4 and 5 digits). The difficulty of the cognitive task was seen to have different effects on adolescents and young adults. Adolescents seem to prioritize postural control during high difficulty postural conditions while a cross-domain competition model appeared in easy postural conditions. Copyright © 2017 Elsevier B.V. All rights reserved.
Mahy, Caitlin E V; Moses, Louis J; Kliegel, Matthias
2014-11-01
The current study examined the impact of age, ongoing task (OT) difficulty, and cue salience on 4- and 5-year-old children's prospective memory (PM) and also explored the relation between individual differences in executive function (working memory, inhibition, and shifting) and PM. OT difficulty and cue salience are predicted to affect the detection of PM cues based on the multiprocess framework, yet neither has been thoroughly investigated in young children. OT difficulty was manipulated by requiring children to sort cards according to the size of pictured items (easy) or by opposite size (difficult), and cue salience was manipulated by placing a red border around half of the target cues (salient) and no border around the other cues (non-salient). The 5-year-olds outperformed the 4-year-olds on the PM task, and salient PM cues resulted in better PM cues compared with non-salient cues. There was no main effect of OT difficulty, and the interaction between cue salience and OT difficulty was not significant. However, a planned comparison revealed that the combination of non-salient cues and a difficult OT resulted in significantly worse PM performance than that in all of the other conditions. Inhibition accounted for significant variance in PM performance for non-salient cues and for marginally significant variance for salient cues. Furthermore, individual differences in inhibition fully mediated the effect of age on PM performance. Results are discussed in the context of the multiprocess framework and with reference to preschoolers' difficulty with the executive demands of dividing attention between the OT and PM task. Copyright © 2014 Elsevier Inc. All rights reserved.
The relation of depression and anxiety to life-stress and achievement in students.
Andrews, Bernice; Wilding, John M
2004-11-01
An apparent increase in seriously disturbed students consulting student health services in the UK has led to concern that increasing financial difficulties and other outside pressures may affect student mental health and academic performance. The current research investigated whether student anxiety and depression increases after college entry, the extent to which adverse life experiences contribute to any increases, and the impact of adversity, anxiety and depression on exam performance. 351 UK-domiciled undergraduates completed questionnaires one month before university entry and mid-course. The Hospital Anxiety and Depression Scale (HADS: Zigmond & Snaith, 1983) was administered at both time points and a modified List of Threatening Experiences (Brugha, Bebbington, Tennant, & Hurry, 1985) was administered mid-course. By mid-course 9% of previously symptom-free students became depressed and 20% became anxious at a clinically significant level. Of those previously anxious or depressed 36% had recovered. After adjusting for pre-entry symptoms, financial difficulties made a significant independent contribution to depression and relationship difficulties independently predicted anxiety. Depression and financial difficulties mid-course predicted a decrease in exam performance from first to second year. This is the first study to confirm empirically that financial and other difficulties can increase British students' levels of anxiety and depression and that financial difficulties and depression can affect academic performance. However, university life may also have a beneficial effect for some students with pre-existing conditions. With widening participation in higher education, the results have important implications for educational and health policies.
Katahira, Kenji; Yamazaki, Yoichi; Yamaoka, Chiaki; Ozaki, Hiroaki; Nakagawa, Sayaka; Nagata, Noriko
2018-01-01
Flow experience is a subjective state experienced during holistic involvement in a certain activity, which has been reported to function as a factor promoting motivation, skill development, and better performance in the activity. To verify the positive effects of flow and develop a method to utilize it, the establishment of a reliable measurement of the flow state is essential. The present study utilized an electroencephalogram (EEG) during an experimentally evoked flow state and examined the possibility of objective measurement of immediate flow. A total of 16 participants (10 males, 6 females) participated in the experiment that employed a mental arithmetic task developed in a previous study. Post-trial self-report of the flow state and EEG during task execution were measured and compared among three conditions (Boredom, Flow, and Overload) that had different levels of task difficulty. Furthermore, the correlations between subjective flow items and EEG activity were examined. As expected, the ratings on the subjective evaluation items representing the flow state were the highest in the Flow condition. Regarding the EEG data, theta activities in the frontal areas were higher in the Flow and the Overload conditions than in the Boredom condition, and alpha activity in the frontal areas and the right central area gradually increased depending on the task difficulty. These EEG activities correlated with self-reported flow experience, especially items related to the concentration on the task and task difficulty. From the results, the flow state was characterized by increased theta activities in the frontal areas and moderate alpha activities in the frontal and central areas. The former may be related to a high level of cognitive control and immersion in task, and the latter suggests that the load on the working memory was not excessive. The findings of this study suggest the possibility of distinguishing the flow state from other states using multiple EEG activities and indicate the need for other physiological indicators corresponding to the other aspects of flow experience.
Katahira, Kenji; Yamazaki, Yoichi; Yamaoka, Chiaki; Ozaki, Hiroaki; Nakagawa, Sayaka; Nagata, Noriko
2018-01-01
Flow experience is a subjective state experienced during holistic involvement in a certain activity, which has been reported to function as a factor promoting motivation, skill development, and better performance in the activity. To verify the positive effects of flow and develop a method to utilize it, the establishment of a reliable measurement of the flow state is essential. The present study utilized an electroencephalogram (EEG) during an experimentally evoked flow state and examined the possibility of objective measurement of immediate flow. A total of 16 participants (10 males, 6 females) participated in the experiment that employed a mental arithmetic task developed in a previous study. Post-trial self-report of the flow state and EEG during task execution were measured and compared among three conditions (Boredom, Flow, and Overload) that had different levels of task difficulty. Furthermore, the correlations between subjective flow items and EEG activity were examined. As expected, the ratings on the subjective evaluation items representing the flow state were the highest in the Flow condition. Regarding the EEG data, theta activities in the frontal areas were higher in the Flow and the Overload conditions than in the Boredom condition, and alpha activity in the frontal areas and the right central area gradually increased depending on the task difficulty. These EEG activities correlated with self-reported flow experience, especially items related to the concentration on the task and task difficulty. From the results, the flow state was characterized by increased theta activities in the frontal areas and moderate alpha activities in the frontal and central areas. The former may be related to a high level of cognitive control and immersion in task, and the latter suggests that the load on the working memory was not excessive. The findings of this study suggest the possibility of distinguishing the flow state from other states using multiple EEG activities and indicate the need for other physiological indicators corresponding to the other aspects of flow experience. PMID:29593605
Diaz, Michele T.; Rizio, Avery A.; Zhuang, Jie
2016-01-01
Although healthy aging is generally characterized by declines in both brain structure and function, there is variability in the extent to which these changes result in observable cognitive decline. Specific to language, age-related differences in language production are observed more frequently than in language comprehension, although both are associated with increased right prefrontal cortex activation in older adults. The current paper explores these differences in the language system, integrating them with theories of behavioral and neural cognitive aging. Overall, data indicate that frontal reorganization of the dorsal language stream in older adults benefits task performance during comprehension, but not always during production. We interpret these results in the CRUNCH framework (compensation-related utilization of neural circuits hypothesis), which suggests that differences in task and process difficulty may underlie older adults’ ability to successfully adapt. That is, older adults may be able to neurally adapt to less difficult tasks (i.e., comprehension), but fail to do so successfully as difficulty increases (i.e., production). We hypothesize greater age-related differences in aspects of language that rely more heavily on the dorsal language stream (e.g., syntax and production) and that recruit general cognitive resources that rely on frontal regions (e.g., executive function, working memory, inhibition). Moreover, there should be a relative sparing of tasks that rely predominantly on ventral stream regions. These results are both consistent with patterns of age-related structural decline and retention and with varying levels of difficulty across comprehension and production. This neurocognitive framework for understanding age-related differences in the language system centers on the interaction between prefrontal cortex activation, structural integrity, and task difficulty. PMID:28210287
Overcoming Intuition: Metacognitive Difficulty Activates Analytic Reasoning
ERIC Educational Resources Information Center
Alter, Adam L.; Oppenheimer, Daniel M.; Epley, Nicholas; Eyre, Rebecca N.
2007-01-01
Humans appear to reason using two processing styles: System 1 processes that are quick, intuitive, and effortless and System 2 processes that are slow, analytical, and deliberate that occasionally correct the output of System 1. Four experiments suggest that System 2 processes are activated by metacognitive experiences of difficulty or disfluency…
Preterm Birth and Leisure Participation: A Synthesis of the Literature
ERIC Educational Resources Information Center
Dahan-Oliel, Noemi; Mazer, Barbara; Majnemer, Annette
2012-01-01
Leisure participation has been associated with happiness and well-being in children. Individuals born preterm are at greater risk for motor, cognitive and behavioral difficulties which may contribute to difficulties participating in leisure activities. This systematic review examined the current knowledge on participation in leisure activities in…
Aspects of Motor Performance and Preacademic Learning.
ERIC Educational Resources Information Center
Feder, Katya; Kerr, Robert
1996-01-01
The Miller Assessment for Preschoolers (MAP) and a number/counting test were given to 50 4- and 5-year-olds. Low performance on counting was related to significantly slower average response time, overshoot movement time, and reaction time, indicating perceptual-motor difficulty. Low MAP scores indicated difficulty processing visual spatial…
Prediction and Stability of Mathematics Skill and Difficulty
ERIC Educational Resources Information Center
Martin, Rebecca B.; Cirino, Paul T.; Barnes, Marcia A.; Ewing-Cobbs, Linda; Fuchs, Lynn S.; Stuebing, Karla K.; Fletcher, Jack M.
2013-01-01
The present study evaluated the stability of math learning difficulties over a 2-year period and investigated several factors that might influence this stability (categorical vs. continuous change, liberal vs. conservative cut point, broad vs. specific math assessment); the prediction of math performance over time and by performance level was also…
Method of encouraging attention by correlating video game difficulty with attention level
NASA Technical Reports Server (NTRS)
Pope, Alan T. (Inventor); Bogart, Edward H. (Inventor)
1994-01-01
A method of encouraging attention in persons such as those suffering from Attention Deficit Disorder is provided by correlating the level of difficulty of a video game with the level of attention in a subject. A conventional video game comprises a video display which depicts objects for interaction with a player and a difficulty adjuster which increases the difficulty level, e.g., action speed and/or evasiveness of the depicted object, in a predetermined manner. The electrical activity of the brain is measured at selected sites to determine levels of awareness, e.g., activity in the beta, theta, and alpha states. A value is generated based on this measured electrical signal which is indicative of the level of awareness. The difficulty level of the game is increased as the awareness level value decreases and is decreased as this awareness level value increases.
Blink activity and task difficulty.
Tanaka, Y; Yamaoka, K
1993-08-01
This study investigated the relationship between task difficulty and blink activity, which includes blink rate, blink amplitude, and blink duration. Two kinds of tasks established two levels of difficulty. In Exp. 1, a mental arithmetic task was used to examine the relationship. Analysis showed that blink rate for a difficult task was significantly higher than that for an easier one. In Exp. 2, a letter-search task (hiragana Japanese alphabet) was used while the other conditions were the same as those in Exp. 1; however, the results of this experiment were not influenced by the difficulty of the task. As results indicate that blink rate is related to not only difficulty but also the nature of the task, the nature of the task is probably dependent on a mechanism in information processing. The results for blink amplitude and blink duration showed no systematic change during either experiment.
Situating Student Errors: Linguistic-to-Algebra Translation Errors
ERIC Educational Resources Information Center
Adu-Gyamfi, Kwaku; Bossé, Michael J.; Chandler, Kayla
2015-01-01
While it is well recognized that students are prone to difficulties when performing linguistic-to-algebra translations, the nature of students' difficulties remain an issue of contention. Moreover, the literature indicates that these difficulties are not easily remediated by domain-specific instruction. Some have opined that this is the case…
Han, Pi-Guo; Han, Lei; Bian, Yu-Long; Tian, Yu; Xu, Min-Xia; Gao, Feng-Qiang
2017-01-01
Prospective memory (PM) is the process associated with the task of realizing delayed intentions in the future. Researchers distinguish two types of PM, namely time-based PM (tbPM) and event-based PM (ebPM). Experiment 1 investigated the developmental trajectory of 3- to 5-year-old preschool children's PM ability, and the occurrence of delayed retrieval (children execute the PM task in a larger window of opportunity) in both tbPM and ebPM tasks. Results revealed that the 5-year-old children outperformed the 3- and 4-year-old children in PM. Moreover, delayed retrieval was more likely to occur in tbPM task than in ebPM task. In Experiment 2, the influence of ongoing task (OT) difficulty on PM performance was investigated with a sample of 5-year-old children. Results revealed no significant effect of OT difficulty on PM performance. In Experiment 3, we improved children's motivation level to complete the OT, then explored the influence of OT difficulty on children's PM performance. Results revealed that the effect of OT difficulty on PM performance became significant after increasing the children's motivation to complete the OT. These results provide insights into the mechanism of attentional resource allocation in PM tasks and have crucial educational and social implications.
Uniform task level definitions for robotic system performance comparisons
NASA Technical Reports Server (NTRS)
Price, Charles; Tesar, Delbert
1989-01-01
A series of ten task levels of increasing difficulty was compiled for use in comparative performance evaluations of available and future robotics technology. Each level has a breakdown of ten additional levels of difficulty to provide a layering of 100 levels. It is assumed that each level of task performance must be achieved by the system before it can be appropriately considered for the next level.
Human activity discrimination for maritime application
NASA Astrophysics Data System (ADS)
Boettcher, Evelyn; Deaver, Dawne M.; Krapels, Keith
2008-04-01
The US Army RDECOM CERDEC Night Vision and Electronic Sensors Directorate (NVESD) is investigating how motion affects the target acquisition model (NVThermIP) sensor performance estimates. This paper looks specifically at estimating sensor performance for the task of discriminating human activities on watercraft, and was sponsored by the Office of Naval Research (ONR). Traditionally, sensor models were calibrated using still images. While that approach is sufficient for static targets, video allows one to use motion cues to aid in discerning the type of human activity more quickly and accurately. This, in turn, will affect estimated sensor performance and these effects are measured in order to calibrate current target acquisition models for this task. The study employed an eleven alternative forced choice (11AFC) human perception experiment to measure the task difficulty of discriminating unique human activities on watercrafts. A mid-wave infrared camera was used to collect video at night. A description of the construction of this experiment is given, including: the data collection, image processing, perception testing and how contrast was defined for video. These results are applicable to evaluate sensor field performance for Anti-Terrorism and Force Protection (AT/FP) tasks for the U.S. Navy.
Tanaka, Masaaki; Ishii, Akira; Watanabe, Yasuyoshi
2015-11-05
Fatigue, defined as difficulty initiating or sustaining voluntary activities, can be classified as physical or mental. In this study, we use magnetoencephalography (MEG) to quantify the effect of physical fatigue on neural activity under the condition of simulated physical load. Thirteen healthy right-handed male volunteers participated in this study. The experiment consisted of one fatigue-inducing physical task session performed between two MEG sessions. During the 10-min physical task session, participants performed maximum-effort handgrips with the left hand lasting 1 s every 4 s; during MEG sessions, 3-min recordings were made during the eyes-closed state. MEG data were analyzed using narrow-band adaptive spatial filtering methods. Alpha-frequency band (8-13 Hz) power in the left postcentral gyrus, precentral gyrus, and middle frontal gyrus (Brodmann's areas 1, 2, 3, 4, 6, and 46) were decreased after performing the physical fatigue-inducing task. These results show that performing the physical fatigue-inducing task caused activation of the left sensorimotor and prefrontal areas, manifested as decreased alpha-frequency band power in these brain areas. Our results increase understanding of the neural mechanisms of physical fatigue.
Student learning styles in anatomy and physiology courses: Meeting the needs of nursing students.
Johnston, A N B; Hamill, J; Barton, M J; Baldwin, S; Percival, J; Williams-Pritchard, G; Salvage-Jones, J; Todorovic, M
2015-11-01
Anatomy and Physiology is a core course in pre-registration nursing programs, yet many students have difficulty successfully negotiating the large volume of content and the complex concepts in these bioscience courses. Typically students perform poorly in these 'threshold' courses', despite multiple interventions to support student engagement. Investigation of the shortcomings in these courses, based on feedback from students indicated several key areas of difficulty in the course, especially focused around a relative lack of hands-on 'concrete' activities in laboratories and tutorials. To attempt to address this, academic and technical staff developed activities for students that promoted discussion and allowed students to interact easily and repetitively with content. Interactive tables and posters that needed to be labelled or 'filled-in' using pre-prepared Velcro dots, as well as pre-prepared flash cards to promote group work, were some examples of the activities used to enhance student experiences and promote hands-on learning. Over the academic year of 2013 these activities were introduced into the laboratory and tutorial classes for first year Bachelor of Nursing anatomy and physiology students. Staff and student participants positively rated implementation of these new activities on surveys, as they allowed them to explore the difficult aspects of anatomy and physiology, utilising various learning styles that may have been neglected in the past. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.
A study on task difficulty and acceleration stress
NASA Technical Reports Server (NTRS)
Repperger, D. W.; Rogers, D. B.
1981-01-01
The results of two experiments which relate to task difficulty and the effects of environmental stress on tracking performance are discussed and compared to subjective evaluations. The first experiment involved five different sum of sine tracking tasks which humans tracked both in a static condition and under a 5 Gz acceleration stress condition. The second experiment involved similar environmental stress conditions but in this case the tasks were constructed from deterministic functions with specially designed velocity and acceleration profiles. Phase Plane performance analysis was conducted to study potential measures of workload or tracking difficulty.
Kramer, Megan E.; Chiu, C.-Y. Peter; Shear, Paula K.; Wade, Shari L.
2010-01-01
Children with traumatic brain injury (TBI) often experience memory deficits, although the nature, functional implication, and recovery trajectory of such difficulties are poorly understood. The present fMRI study examined the neural activation patterns in a group of young children who sustained moderate TBI in early childhood (n = 7), and a group of healthy control children (n = 13) during a verbal paired associate learning (PAL) task that promoted the use of two mnemonic strategies differing in efficacy. The children with TBI demonstrated intact memory performance and were able to successfully utilize the mnemonic strategies. However, the TBI group also demonstrated altered brain activation patterns during the task compared to the control children. These findings suggest early childhood TBI may alter activation within the network of brain regions supporting associative memory even in children who show good behavioral performance. PMID:21188286
Hughes, Charmayne M L; Baber, Chris; Bienkiewicz, Marta; Worthington, Andrew; Hazell, Alexa; Hermsdörfer, Joachim
2015-01-01
Approximately 33% of stroke patients have difficulty performing activities of daily living, often committing errors during the planning and execution of such activities. The objective of this study was to evaluate the ability of the human error identification (HEI) technique SHERPA (Systematic Human Error Reduction and Prediction Approach) to predict errors during the performance of daily activities in stroke patients with left and right hemisphere lesions. Using SHERPA we successfully predicted 36 of the 38 observed errors, with analysis indicating that the proportion of predicted and observed errors was similar for all sub-tasks and severity levels. HEI results were used to develop compensatory cognitive strategies that clinicians could employ to reduce or prevent errors from occurring. This study provides evidence for the reliability and validity of SHERPA in the design of cognitive rehabilitation strategies in stroke populations.
NASA Technical Reports Server (NTRS)
Liu, Yili; Wickens, Christopher D.
1987-01-01
This paper reports on the first experiment of a series studying the effect of task structure and difficulty demand on time-sharing performance and workload in both automated and corresponding manual systems. The experimental task involves manual control time-shared with spatial and verbal decisions tasks of two levels of difficulty and two modes of response (voice or manual). The results provide strong evidence that tasks and processes competing for common processing resources are time shared less effecively and have higher workload than tasks competing for separate resources. Subjective measures and the structure of multiple resources are used in conjunction to predict dual task performance. The evidence comes from both single-task and from dual-task performance.
Gaming is related to enhanced working memory performance and task-related cortical activity.
Moisala, M; Salmela, V; Hietajärvi, L; Carlson, S; Vuontela, V; Lonka, K; Hakkarainen, K; Salmela-Aro, K; Alho, K
2017-01-15
Gaming experience has been suggested to lead to performance enhancements in a wide variety of working memory tasks. Previous studies have, however, mostly focused on adult expert gamers and have not included measurements of both behavioral performance and brain activity. In the current study, 167 adolescents and young adults (aged 13-24 years) with different amounts of gaming experience performed an n-back working memory task with vowels, with the sensory modality of the vowel stream switching between audition and vision at random intervals. We studied the relationship between self-reported daily gaming activity, working memory (n-back) task performance and related brain activity measured using functional magnetic resonance imaging (fMRI). The results revealed that the extent of daily gaming activity was related to enhancements in both performance accuracy and speed during the most demanding (2-back) level of the working memory task. This improved working memory performance was accompanied by enhanced recruitment of a fronto-parietal cortical network, especially the dorsolateral prefrontal cortex. In contrast, during the less demanding (1-back) level of the task, gaming was associated with decreased activity in the same cortical regions. Our results suggest that a greater degree of daily gaming experience is associated with better working memory functioning and task difficulty-dependent modulation in fronto-parietal brain activity already in adolescence and even when non-expert gamers are studied. The direction of causality within this association cannot be inferred with certainty due to the correlational nature of the current study. Copyright © 2016 Elsevier B.V. All rights reserved.
Badr, H E; Mourad, H
2009-10-01
To study the role of gender in coping with disability in young visually impaired students attending two schools for blindness. The WHO Disability Assessment Schedule (WHODAS II), 36-Item Interviewer Administered translated Arabic version was used. It evaluates six domains of everyday living in the last 30 days. These domains are: understanding and communicating, getting around, self care, getting along with people, household activities and participation in society. Face-to-face interviews were conducted with 200 students who represented the target population of the study. Binary logistic regression analysis of the scores of the six domains revealed that in all of the domains except getting along with people and coping with school activities, females significantly faced more difficulties in coping with daily life activities than did their male counterparts. Increasing age significantly increased difficulties in coping with school activities. Genetic causes of blindness were associated with increased difficulties. Females face more difficulties in coping with visual disability. Genetic counselling is needed to decrease the prevalence of visual disability. Girls with blindness need additional inputs to help cope with blindness. Early intervention facilitates dealing with school activities of the visually impaired.
Kucian, Karin; Loenneker, Thomas; Martin, Ernst; von Aster, Michael
2011-01-01
This study investigated areas of brain activation related to non-symbolic distance effects in children with and without developmental dyscalculia (DD). We examined 15 children with DD (11.3 years) and 15 controls (10.6 years) by means of functional magnetic resonance imaging (fMRI). Both groups displayed similar behavioral performance, but differences in brain activation were observed, particularly in the supplementary motor area and the right fusiform gyrus, where children with DD demonstrated stronger activation. These results suggest that dyscalculic children engage areas attributed to higher difficulty in response selection more than control children, possibly due to a deficient development of a spatial number representation in DD.
Intrusion errors in visuospatial working memory performance.
Cornoldi, Cesare; Mammarella, Nicola
2006-02-01
This study tested the hypothesis that failure in active visuospatial working memory tasks involves a difficulty in avoiding intrusions due to information that is already activated. Two experiments are described, in which participants were required to process several series of locations on a 4 x 4 matrix and then to produce only the final location of each series. Results revealed a higher number of errors due to already activated locations (intrusions) compared with errors due to new locations (inventions). Moreover, when participants were required to pay extra attention to some irrelevant (non-final) locations by tapping on the table, intrusion errors increased. Results are discussed in terms of current models of working memory functioning.
ERIC Educational Resources Information Center
Ramnarain, Umesh; Joseph, Aleyamma
2012-01-01
This study investigated the learning difficulties of grade 12 South African students in a national chemistry examination. A quantitative analysis of students' performance in the examination revealed there was a significant difference between student performance in questions where students needed to execute a transformation across levels of…
The Effect of Pitch and Rhythm Difficulty on Vocal Sight-Reading Performance
ERIC Educational Resources Information Center
Henry, Michele L.
2011-01-01
Singing music at sight is a complex skill, requiring the singer to perform pitch and rhythm simultaneously. Previous research has identified difficulty levels for pitch and rhythm skills individually but not in combination. In this study, the author sought to determine the relationship between pitch and rhythm tasks occurring concurrently. High…
Confronting Task Difficulty in Ego Involvement: Change in Performance Goals
ERIC Educational Resources Information Center
Kumar, Shamala; Jagacinski, Carolyn M.
2011-01-01
Both Dweck (1986) and Nicholls (1984) proposed that when ego-involved individuals encounter difficulty, they would begin to doubt their level of ability, and as a consequence, their commitment to the goal of demonstrating high ability would decline. As difficulty continued, perceived ability would decline, and eventually the goal would be…
Internal and External Difficulties in Moral Education
ERIC Educational Resources Information Center
Dan, Jau Wei
2012-01-01
Certain difficulties pervade the course of moral education and in this essay a broad picture of these shall be sketched. Moral educators need to understand the problems they will face if they intend to enhance their performance; this includes knowing the limits of moral education, and not going beyond their capacities. These difficulties may be…
Statistical Approaches to the Study of Item Difficulty.
ERIC Educational Resources Information Center
Olson, John F.; And Others
Traditionally, item difficulty has been defined in terms of the performance of examinees. For test development purposes, a more useful concept would be some kind of intrinsic item difficulty, defined in terms of the item's content, context, or characteristics and the task demands set by the item. In this investigation, the measurement literature…
Menzies, Lara; Ooi, Cinly; Kamath, Shri; Suckling, John; McKenna, Peter; Fletcher, Paul; Bullmore, Ed; Stephenson, Caroline
2007-02-01
Cognitive impairment causes morbidity in schizophrenia and could be due to abnormalities of cortical interneurons using the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). To test the predictions that cognitive and brain functional responses to GABA-modulating drugs are correlated and abnormal in schizophrenia. Pharmacological functional magnetic resonance imaging study of 2 groups, each undergoing scanning 3 times, using an N-back working memory task, after placebo, lorazepam, or flumazenil administration. Eleven patients with chronic schizophrenia were recruited from a rehabilitation service, and 11 healthy volunteers matched for age, sex, and premorbid IQ were recruited from the local community. Intervention Participants received 2 mg of oral lorazepam, a 0.9-mg intravenous flumazenil bolus followed by a flumazenil infusion of 0.0102 mg/min, or oral and intravenous placebo. Working memory performance was summarized by the target discrimination index at several levels of difficulty. Increasing (or decreasing) brain functional activation in response to increasing task difficulty was summarized by the positive (or negative) load response. Lorazepam impaired performance and flumazenil enhanced it; these cognitive effects were more salient in schizophrenic patients. Functional magnetic resonance imaging demonstrated positive load response in a frontoparietal system and negative load response in the temporal and posterior cingulate regions; activation of the frontoparietal cortex was positively correlated with deactivation of the temporocingulate cortex. After placebo administration, schizophrenic patients had abnormally attenuated activation of the frontoparietal cortex and deactivation of the temporocingulate cortex; this pattern was mimicked in healthy volunteers and exacerbated in schizophrenic patients by lorazepam. However, in schizophrenic patients, flumazenil enhanced deactivation of the temporocingulate and activation of the anterior cingulate cortices. The GABA-modulating drugs differentially affect working memory performance and brain function in schizophrenia. Cognitive impairment in schizophrenia may reflect abnormal inhibitory function and could be treated by drugs targeting GABA neurotransmission.
Klemanski, David H; Mennin, Douglas S; Borelli, Jessica L; Morrissey, Paul M; Aikins, Deane E
2012-07-01
Data suggest military personnel involved in U.S. military initiatives in Iraq and Afghanistan are returning from deployment with elevated rates of mental health diagnoses, including posttraumatic stress disorder (PTSD). The aim of this study was to examine difficulties with emotion regulation as a potential contributory mechanism by which soldiers have poorer psychological outcomes, such as depression, dissociation, alcohol abuse, and interpersonal difficulties. Participants were 44 active-duty male service members who comprised three groups, including those deployed with and without diagnosed PTSD and those prior to deployment. Participants in the PTSD group scored significantly higher on measures of self-reported depression, trauma-related dissociation, alcohol misuse, and social adjustment difficulties than did comparison groups. Importantly, difficulties with emotion regulation were found to partially mediate the relationship between PTSD and depression, poor social adjustment, and trauma-related depersonalization but not alcohol misuse. Emotion-regulation difficulties are important to consider in the relationship between PTSD and additional psychological outcomes in recently deployed personnel. Implications for treatment are briefly discussed. © 2012 Wiley Periodicals, Inc.
NASA Technical Reports Server (NTRS)
Hart, S. G.
1975-01-01
Variation in the length of time productions and verbal estimates of duration was investigated to determine the influence of concurrent activity on operator time perception. The length of 10-, 20-, and 30-sec intervals produced while performing six different compensatory tracking tasks was significantly longer, 23% on the average, than those produced while performing no other task. Verbal estimates of session duration, taken at the end of each of 27 experimental sessions, reflected a parallel increase in subjective underestimation of the passage of time as the difficulty of the task performed increased. These data suggest that estimates of duration made while performing a manual control task provide stable and sensitive measures of the workload imposed by the primary task, with minimal interference.
Brain regions underlying word finding difficulties in temporal lobe epilepsy.
Trebuchon-Da Fonseca, Agnes; Guedj, Eric; Alario, F-Xavier; Laguitton, Virginie; Mundler, Olivier; Chauvel, Patrick; Liegeois-Chauvel, Catherine
2009-10-01
Word finding difficulties are often reported by epileptic patients with seizures originating from the language dominant cerebral hemisphere, for example, in temporal lobe epilepsy. Evidence regarding the brain regions underlying this deficit comes from studies of peri-operative electro-cortical stimulation, as well as post-surgical performance. This evidence has highlighted a role for the anterior part of the dominant temporal lobe in oral word production. These conclusions contrast with findings from activation studies involving healthy speakers or acute ischaemic stroke patients, where the region most directly related to word retrieval appears to be the posterior part of the left temporal lobe. To clarify the neural basis of word retrieval in temporal lobe epilepsy, we tested forty-three drug-resistant temporal lobe epilepsy patients (28 left, 15 right). Comprehensive neuropsychological and language assessments were performed. Single spoken word production was elicited with picture or definition stimuli. Detailed analysis allowed the distinction of impaired word retrieval from other possible causes of naming failure. Finally, the neural substrate of the deficit was assessed by correlating word retrieval performance and resting-state brain metabolism in 18 fluoro-2-deoxy-d-glucose-Positron Emission Tomography. Naming difficulties often resulted from genuine word retrieval failures (anomic states), both in picture and in definition tasks. Left temporal lobe epilepsy patients showed considerably worse performance than right temporal lobe epilepsy patients. Performance was poorer in the definition than in the picture task. Across patients and the left temporal lobe epilepsy subgroup, frequency of anomic state was negatively correlated with resting-state brain metabolism in left posterior and basal temporal regions (Brodmann's area 20-37-39). These results show the involvement of posterior temporal regions, within a larger antero-posterior-basal temporal network, in the specific process of word retrieval in temporal lobe epilepsy. A tentative explanation for these findings is that epilepsy induces functional deafferentation between anterior temporal structures devoted to semantic processing and neocortical posterior temporal structures devoted to lexical processing.
Contribution of occupational therapy to the assessment of competence: A case study
Blanchet, Marie; Huynh, Tammy; Giroux, Dominique; Bottari, Carolina
2016-06-01
Many occupational therapists contribute to the assessment of competence to take care of oneself and manage one’s affairs, but few guidelines exist regarding this practice with adults who have experienced a traumatic brain injury (TBI). This study explored the ability of the Instrumental Activities of Daily Living Profile (IADL Profile) to capture competence following a TBI. Task performance on the IADL Profile of a 46-year-old man (ML) who was found to be incompetent following a severe TBI was compared to eight control subjects (mean age 49.3 ± 4.2 years). The IADL Profile scores, observable behaviours, and verbalizations were compared using descriptive statistics (M, SD) and qualitative analyses. The independence level of ML was lower than that of the control subjects on seven of the eight tasks of the IADL Profile (p < .05), especially for preparing a hot meal and creating a budget. ML demonstrated difficulties that impacted his performance on many tasks, and he had difficulty critiquing his results. The IADL Profile could be used as part of a functional assessment to document competence. © CAOT 2016.
[Children with developmental coordination disorder have difficulty with action representation].
Gabbard, Carl; Cacola, Priscila
The study of children with developmental coordination disorder (DCD) has emerged as a vibrant line of inquiry over the last two decades. The literature indicates quite clearly that children with DCD display deficits with an array of perceptual-motor and daily living skills. The movements of children with DCD are often described as clumsy and uncoordinated and lead to difficulties with performing many of the activities of daily living and sports that typically developing children perform easily. It has been hypothesized, based on limited research, that an underlying problem is a deficit in generating and/or monitoring an action representation termed the internal modeling deficit hypothesis. According to the hypothesis, children with DCD have significant limitations in their ability to accurately generate and utilize internal models of motor planning and control. The focus of this review is on one of the methods used to examine action representation-motor imagery, which theorists argue provides a window into the process of action representation. Included are research methods and possible brain structures involved. An addition, a paradigm unique with this population-estimation of reachability (distance) via motor imagery, will be described.
Gignac, Monique A M; Cao, Xingshan; Tang, Kenneth; Beaton, Dorcas E
2011-07-01
To examine the type, degree, and episodic nature of arthritis-related work place activity limitations and the consistency of the relationship of activity limitations to job modifications and work place outcomes. Using an interviewer-administered structured questionnaire, individuals with osteoarthritis (OA) or inflammatory arthritis (IA) were interviewed at 4 time points, 18 months apart. At baseline, all participants (n = 490; 381 women, 109 men) were employed. Respondents were recruited using community advertising and from rheumatology and rehabilitation clinics. The Workplace Activity Limitations Scale (WALS) assessed arthritis-related disability with job tasks. Job modifications/accommodations (e.g., scheduling changes), work place outcomes (e.g., absenteeism), demographics, illness, and work context were also measured. Repeated cross-sectional logistic regressions examined levels of WALS disability with job modifications and outcomes at each time point. Similar levels of activity limitations were found comparing OA and IA with fewer difficulties with global aspects of work (e.g., scheduling) than with specific tasks (e.g., working with hands). Three-quarters of the participants had episodic or intermittent WALS difficulty over time. Medium and high levels of work place activity limitations were significantly associated with job modifications, and high WALS difficulty was consistently related to negative work outcomes. Many individuals with arthritis report some difficulty with work place activities. However, these difficulties are often intermittent and may not result in changes to work productivity until they are consistently high. This is important for designing work place interventions and for employers, insurers, and the government to understand to avoid viewing individuals with arthritis as a permanent drain on work place and health resources. Copyright © 2011 by the American College of Rheumatology.
Human-centric predictive model of task difficulty for human-in-the-loop control tasks
Majewicz Fey, Ann
2018-01-01
Quantitatively measuring the difficulty of a manipulation task in human-in-the-loop control systems is ill-defined. Currently, systems are typically evaluated through task-specific performance measures and post-experiment user surveys; however, these methods do not capture the real-time experience of human users. In this study, we propose to analyze and predict the difficulty of a bivariate pointing task, with a haptic device interface, using human-centric measurement data in terms of cognition, physical effort, and motion kinematics. Noninvasive sensors were used to record the multimodal response of human user for 14 subjects performing the task. A data-driven approach for predicting task difficulty was implemented based on several task-independent metrics. We compare four possible models for predicting task difficulty to evaluated the roles of the various types of metrics, including: (I) a movement time model, (II) a fusion model using both physiological and kinematic metrics, (III) a model only with kinematic metrics, and (IV) a model only with physiological metrics. The results show significant correlation between task difficulty and the user sensorimotor response. The fusion model, integrating user physiology and motion kinematics, provided the best estimate of task difficulty (R2 = 0.927), followed by a model using only kinematic metrics (R2 = 0.921). Both models were better predictors of task difficulty than the movement time model (R2 = 0.847), derived from Fitt’s law, a well studied difficulty model for human psychomotor control. PMID:29621301
Sleep difficulties and academic performance in Norwegian higher education students.
Hayley, Amie C; Sivertsen, Børge; Hysing, Mari; Vedaa, Øystein; Øverland, Simon
2017-12-01
Sleep difficulties are common among university students and may detrimentally affect academic outcomes. Despite this, remarkably little information is currently available during this critical developmental period of early adulthood, and thus, the direct effect on measurable domains of academic ability and proficiency is equivocal. To evaluate the associations between difficulties initiating and maintaining sleep (DIMS) and subjective and objective academic performance in a large sample of university students. A total of 12,915 students who participated in large student survey in Norway from 24 February 2014 to 27 March 2014. DIMS was assessed by the Hopkins Symptoms Checklist (HSCL-25), and academic outcomes included failed examinations, delayed study progress, and school-related self-efficacy (General Self-Efficacy Scale). Difficulties initiating and maintaining sleep was independently associated with increased odds for poor school performance for all academic outcomes. Reporting 'extreme' DIMS was associated with increased odds of reporting delayed study progress (adjusted odds ratio [OR] = 1.25, 95% CI 1.01-1.57, p < .05), increased odds for having failed several examinations (adjusted OR = 1.91, 95% CI 1.56-2.34, p < .001), and being in the lowest self-efficacy quartile (adjusted OR = 4.94, 95% CI: 4.04-6.03, p < .001). Self-reported sleep difficulties are associated with poorer objective markers of academic outcomes as well as poorer self-rated academic proficiency among higher education students. Amelioration of sleep difficulties may improve overall academic performance and health outcomes in affected students. © 2017 The British Psychological Society.
Honan, Cynthia A; Brown, Rhonda F; Batchelor, Jennifer
2015-02-01
Perceived cognitive difficulties and cognitive impairment are important determinants of employment in people with multiple sclerosis (pwMS). However, it is not clear how they are related to adverse work outcomes and whether the relationship is influenced by depressive symptoms. Thus, this study examined perceived and actual general cognitive and prospective memory function, and cognitive appraisal accuracy, in relation to adverse work outcomes. The possible mediating and/or moderating role of depression was also examined. A cross-sectional community-based sample of 111 participants (33 males, 78 females) completed the Multiple Sclerosis Work Difficulties Questionnaire (MSWDQ), Beck Depression Inventory - Fast Screen (BDI-FS), and questions related to their current or past employment. They then underwent cognitive testing using the Screening Examination for Cognitive Impairment, Auditory Consonant Trigrams test, Zoo Map Test, and Cambridge Prospective Memory Test. Perceived general cognitive and prospective memory difficulties in the workplace and performance on the respective cognitive tests were found to predict unemployment and reduced work hours since MS diagnosis due to MS. Depression was also related to reduced work hours, but it did not explain the relationship between perceived cognitive difficulties and the work outcomes. Nor was it related to cognitive test performance. The results highlight a need to address the perceptions of cognitive difficulties together with cognitive impairment and levels of depression in vocational rehabilitation programs in pwMS.
Boeschoten, K H; Folmer, K B; van der Lee, J H; Nollet, F
2007-02-01
To develop an observational instrument that can be used to evaluate the quality of arm and hand skills in daily functional activities in children with obstetric brachial plexus lesion (OBPL). A set of functional activities was constructed and standardized, and the intra-observer reliability of the assessment of this set of activities was studied. Department of Occupational Therapy and Department of Rehabilitation Medicine, VU University Medical Centre. Twenty-six children with OBPL in the age range of 4 -6 years. The children were asked to perform 47 bimanual activities, which were recorded on videotape. The videotapes were scored twice by the same occupational therapist. The percentage of agreement in scoring 'hand-use', 'speed' and 'assistance' was over 80% for a substantial number of activities, indicating a strong agreement. However, in scoring 'deviations in movements and body posture' the percentage of agreement was insufficient in most activities. This set of activities has good potential for assessment of the performance of functional activities in children with OBPL. This study, however, showed a number of difficulties in observing and scoring the activities that have to be considered when developing a standardized video observation.
Trost, Zina; Van Ryckeghem, Dimitri; Scott, Whitney; Guck, Adam; Vervoort, Tine
2016-11-01
The current study examined the relationship between perceived injustice and attentional bias (AB) toward pain among individuals with chronic low back pain asked to perform and appraise the pain and difficulty of a standardized set of common physical activities. A pictorial dot-probe task assessed AB toward pain stimuli (ie, pain faces cueing pain), after which participants performed the physical tasks. Participants also rated face stimuli in terms of pain, sadness, and anger expression. As hypothesized, perceived injustice was positively associated with AB toward pain stimuli; additionally, perceived injustice and AB were positively associated with appraisals of pain and difficulty. Counter to expectations, AB did not mediate the relationship between perceived injustice and task appraisals, suggesting that AB is insufficient to explain this relationship. Exploratory analyses indicated that participants with higher levels of perceived injustice rated stimulus faces as sadder and angrier; no such differences emerged for pain ratings. To our knowledge, this is the first study to examine the association between perceived injustice and AB toward pain, as well as perceived injustice and in vivo appraisals of common physical activity. Results extend existing literature and suggest that attentional and potential interpretive bias should be considered in future research. This article identifies significant associations between perceived injustice, biased attention to pain, and appraisals of common physical activities among individuals with chronic low back pain. These findings suggest targets for intervention as well as directions for future research regarding individuals with high perceptions of injustice related to pain. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Basso Moro, Sara; Carrieri, Marika; Avola, Danilo; Brigadoi, Sabrina; Lancia, Stefania; Petracca, Andrea; Spezialetti, Matteo; Ferrari, Marco; Placidi, Giuseppe; Quaresima, Valentina
2016-06-01
Objective. In the last few years, the interest in applying virtual reality systems for neurorehabilitation is increasing. Their compatibility with neuroimaging techniques, such as functional near-infrared spectroscopy (fNIRS), allows for the investigation of brain reorganization with multimodal stimulation and real-time control of the changes occurring in brain activity. The present study was aimed at testing a novel semi-immersive visuo-motor task (VMT), which has the features of being adopted in the field of neurorehabilitation of the upper limb motor function. Approach. A virtual environment was simulated through a three-dimensional hand-sensing device (the LEAP Motion Controller), and the concomitant VMT-related prefrontal cortex (PFC) response was monitored non-invasively by fNIRS. Upon the VMT, performed at three different levels of difficulty, it was hypothesized that the PFC would be activated with an expected greater level of activation in the ventrolateral PFC (VLPFC), given its involvement in the motor action planning and in the allocation of the attentional resources to generate goals from current contexts. Twenty-one subjects were asked to move their right hand/forearm with the purpose of guiding a virtual sphere over a virtual path. A twenty-channel fNIRS system was employed for measuring changes in PFC oxygenated-deoxygenated hemoglobin (O2Hb/HHb, respectively). Main results. A VLPFC O2Hb increase and a concomitant HHb decrease were observed during the VMT performance, without any difference in relation to the task difficulty. Significance. The present study has revealed a particular involvement of the VLPFC in the execution of the novel proposed semi-immersive VMT adoptable in the neurorehabilitation field.
Moro, Sara Basso; Carrieri, Marika; Avola, Danilo; Brigadoi, Sabrina; Lancia, Stefania; Petracca, Andrea; Spezialetti, Matteo; Ferrari, Marco; Placidi, Giuseppe; Quaresima, Valentina
2016-06-01
In the last few years, the interest in applying virtual reality systems for neurorehabilitation is increasing. Their compatibility with neuroimaging techniques, such as functional near-infrared spectroscopy (fNIRS), allows for the investigation of brain reorganization with multimodal stimulation and real-time control of the changes occurring in brain activity. The present study was aimed at testing a novel semi-immersive visuo-motor task (VMT), which has the features of being adopted in the field of neurorehabilitation of the upper limb motor function. A virtual environment was simulated through a three-dimensional hand-sensing device (the LEAP Motion Controller), and the concomitant VMT-related prefrontal cortex (PFC) response was monitored non-invasively by fNIRS. Upon the VMT, performed at three different levels of difficulty, it was hypothesized that the PFC would be activated with an expected greater level of activation in the ventrolateral PFC (VLPFC), given its involvement in the motor action planning and in the allocation of the attentional resources to generate goals from current contexts. Twenty-one subjects were asked to move their right hand/forearm with the purpose of guiding a virtual sphere over a virtual path. A twenty-channel fNIRS system was employed for measuring changes in PFC oxygenated-deoxygenated hemoglobin (O2Hb/HHb, respectively). A VLPFC O2Hb increase and a concomitant HHb decrease were observed during the VMT performance, without any difference in relation to the task difficulty. The present study has revealed a particular involvement of the VLPFC in the execution of the novel proposed semi-immersive VMT adoptable in the neurorehabilitation field.
Jaimes-Bautista, A G; Rodríguez-Camacho, M; Martínez-Juárez, I E; Rodríguez-Agudelo, Y
2017-08-29
Patients with temporal lobe epilepsy (TLE) perform poorly on semantic verbal fluency (SVF) tasks. Completing these tasks successfully involves multiple cognitive processes simultaneously. Therefore, quantitative analysis of SVF (number of correct words in one minute), conducted in most studies, has been found to be insufficient to identify cognitive dysfunction underlying SVF difficulties in TLE. To determine whether a sample of patients with TLE had SVF difficulties compared with a control group (CG), and to identify the cognitive components associated with SVF difficulties using quantitative and qualitative analysis. SVF was evaluated in 25 patients with TLE and 24 healthy controls; the semantic verbal fluency test included 5 semantic categories: animals, fruits, occupations, countries, and verbs. All 5 categories were analysed quantitatively (number of correct words per minute and interval of execution: 0-15, 16-30, 31-45, and 46-60seconds); the categories animals and fruits were also analysed qualitatively (clusters, cluster size, switches, perseverations, and intrusions). Patients generated fewer words for all categories and intervals and fewer clusters and switches for animals and fruits than the CG (P<.01). Differences between groups were not significant in terms of cluster size and number of intrusions and perseverations (P>.05). Our results suggest an association between SVF difficulties in TLE and difficulty activating semantic networks, impaired strategic search, and poor cognitive flexibility. Attention, inhibition, and working memory are preserved in these patients. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.
Aznar-Arasa, L; Figueiredo, R; Valmaseda-Castellón, E; Gay-Escoda, C
2014-09-01
Encountering patients who are fearful and anxious is common in dental practice and these factors can increase the complexity of dental procedures. A prospective cohort study was performed to assess whether patient anxiety influences the difficulty of impacted lower third molar extraction and to identify other predictive factors of surgical difficulty; 102 extractions done under local anaesthesia were assessed. Several preoperative variables were recorded (demographic, anatomical, and surgical) and patient anxiety was assessed through the use of various questionnaires. Extraction difficulty was measured using the operation time (OT) and a 100-mm visual analogue scale (difficulty VAS) completed by the surgeon. Patients with deep impacted third molars that required bone removal and tooth sectioning showed higher levels of preoperative anxiety. Significant correlations were found between questionnaire scores and the surgical difficulty (OT and difficulty VAS). OT was also related to age, depth of impaction, third molar angulations, proximity of the third molar roots to the mandibular canal, hard and soft tissue coverage, and the need to perform an ostectomy and tooth sectioning. Impacted lower third molar extraction is significantly more difficult in anxious patients. Other demographic, radiological, and surgical factors were also found to be significantly related to the surgical difficulty. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Particle Swarm Imaging (PSIM) - Innovative Gamma-Ray Assay - 13497
DOE Office of Scientific and Technical Information (OSTI.GOV)
Parvin, Daniel; Clarke, Sean; Humes, Sarah J.
2013-07-01
Particle Swarm Imaging is an innovative technique used to perform quantitative gamma-ray assay. The innovation overcomes some of the difficulties associated with the accurate measurement and declaration of measurement uncertainties of radionuclide inventories within waste items when the distribution of activity is unknown. Implementation requires minimal equipment, with field measurements and results obtained using only a single electrically cooled HRGS gamma-ray detector. Examples of its application in the field are given in this paper. (authors)
Performance assessment in complex individual and team tasks
NASA Technical Reports Server (NTRS)
Eddy, Douglas R.
1992-01-01
Described here is an eclectic, performance based approach to assessing cognitive performance from multiple perspectives. The experience gained from assessing the effects of antihistamines and scenario difficulty on C (exp 2) decision making performance in Airborne Warning and Control Systems (AWACS) weapons director (WD) teams can serve as a model for realistic simulations in space operations. Emphasis is placed on the flexibility of measurement, hierarchical organization of measurement levels, data collection from multiple perspectives, and the difficulty of managing large amounts of data.
Habeeb, Christine M; Eklund, Robert C; Coffee, Pete
2017-06-01
This study explored person-related sources of variance in athletes' efficacy beliefs and performances when performing in pairs with distinguishable roles differing in partner dependence. College cheerleaders (n = 102) performed their role in repeated performance trials of two low- and two high-difficulty paired-stunt tasks with three different partners. Data were obtained on self-, other-, and collective efficacy beliefs and subjective performances, and objective performance assessments were obtained from digital recordings. Using the social relations model framework, total variance in each belief/assessment was partitioned, for each role, into numerical components of person-related variance relative to the self, the other, and the collective. Variance component by performance role by task-difficulty repeated-measures analysis of variances revealed that the largest person-related variance component differed by athlete role and increased in size in high-difficulty tasks. Results suggest that the extent the athlete's performance depends on a partner relates to the extent the partner is a source of self-, other-, and collective efficacy beliefs.
Rodger, Sylvia; Brandenburg, Julia
2009-02-01
Motor difficulties associated with Asperger's syndrome (AS) are commonly reported, despite these not being diagnostically significant. Cognitive Orientation to daily Occupational Performance (CO-OP) is a verbal problem-solving intervention developed for use with children with developmental coordination disorder to address their motor-based difficulties. This paper reports on two case studies of children with AS illustrating the outcomes of CO-OP to address motor-based occupational performance goals. A case study approach was used to document how two children with AS engaged in 10 weekly sessions of CO-OP addressing child-chosen motor-based occupational performance goals and the outcomes of this intervention. Pre and post-intervention assessment using the Canadian Occupational Performance Measure, Vineland Adaptive Behaviour Scales and the Performance Quality Rating Scale indicated that both children were able to engage in CO-OP intervention to successfully improve their occupational performance. Further research into the application of CO-OP with children with AS is warranted based on preliminary positive findings regarding the efficacy of this intervention to address motor-based performance difficulties in two children with AS.
Caballero Sánchez, Carla; Barbado Murillo, David; Davids, Keith; Moreno Hernández, Francisco J
2016-06-01
This study investigated the extent to which specific interacting constraints of performance might increase or decrease the emergent complexity in a movement system, and whether this could affect the relationship between observed movement variability and the central nervous system's capacity to adapt to perturbations during balancing. Fifty-two healthy volunteers performed eight trials where different performance constraints were manipulated: task difficulty (three levels) and visual biofeedback conditions (with and without the center of pressure (COP) displacement and a target displayed). Balance performance was assessed using COP-based measures: mean velocity magnitude (MVM) and bivariate variable error (BVE). To assess the complexity of COP, fuzzy entropy (FE) and detrended fluctuation analysis (DFA) were computed. ANOVAs showed that MVM and BVE increased when task difficulty increased. During biofeedback conditions, individuals showed higher MVM but lower BVE at the easiest level of task difficulty. Overall, higher FE and lower DFA values were observed when biofeedback was available. On the other hand, FE reduced and DFA increased as difficulty level increased, in the presence of biofeedback. However, when biofeedback was not available, the opposite trend in FE and DFA values was observed. Regardless of changes to task constraints and the variable investigated, balance performance was positively related to complexity in every condition. Data revealed how specificity of task constraints can result in an increase or decrease in complexity emerging in a neurobiological system during balance performance.
Han, Pi-guo; Han, Lei; Bian, Yu-long; Tian, Yu; Xu, Min-xia; Gao, Feng-qiang
2017-01-01
Prospective memory (PM) is the process associated with the task of realizing delayed intentions in the future. Researchers distinguish two types of PM, namely time-based PM (tbPM) and event-based PM (ebPM). Experiment 1 investigated the developmental trajectory of 3- to 5-year-old preschool children’s PM ability, and the occurrence of delayed retrieval (children execute the PM task in a larger window of opportunity) in both tbPM and ebPM tasks. Results revealed that the 5-year-old children outperformed the 3- and 4-year-old children in PM. Moreover, delayed retrieval was more likely to occur in tbPM task than in ebPM task. In Experiment 2, the influence of ongoing task (OT) difficulty on PM performance was investigated with a sample of 5-year-old children. Results revealed no significant effect of OT difficulty on PM performance. In Experiment 3, we improved children’s motivation level to complete the OT, then explored the influence of OT difficulty on children’s PM performance. Results revealed that the effect of OT difficulty on PM performance became significant after increasing the children’s motivation to complete the OT. These results provide insights into the mechanism of attentional resource allocation in PM tasks and have crucial educational and social implications. PMID:28203212
Judging in Rhythmic Gymnastics at Different Levels of Performance.
Leandro, Catarina; Ávila-Carvalho, Lurdes; Sierra-Palmeiro, Elena; Bobo-Arce, Marta
2017-12-01
This study aimed to analyse the quality of difficulty judging in rhythmic gymnastics, at different levels of performance. The sample consisted of 1152 difficulty scores concerning 288 individual routines, performed in the World Championships in 2013. The data were analysed using the mean absolute judge deviation from the final difficulty score, a Cronbach's alpha coefficient and intra-class correlations, for consistency and reliability assessment. For validity assessment, mean deviations of judges' difficulty scores, the Kendall's coefficient of concordance W and ANOVA eta-squared values were calculated. Overall, the results in terms of consistency (Cronbach's alpha mostly above 0.90) and reliability (intra-class correlations for single and average measures above 0.70 and 0.90, respectively) were satisfactory, in the first and third parts of the ranking on all apparatus. The medium level gymnasts, those in the second part of the ranking, had inferior reliability indices and highest score dispersion. In this part, the minimum of corrected item-total correlation of individual judges was 0.55, with most values well below, and the matrix for between-judge correlations identified remarkable inferior correlations. These findings suggest that the quality of difficulty judging in rhythmic gymnastics may be compromised at certain levels of performance. In future, special attention should be paid to the judging analysis of the medium level gymnasts, as well as the Code of Points applicability at this level.
Judging in Rhythmic Gymnastics at Different Levels of Performance
Ávila-Carvalho, Lurdes; Sierra-Palmeiro, Elena; Bobo-Arce, Marta
2017-01-01
Abstract This study aimed to analyse the quality of difficulty judging in rhythmic gymnastics, at different levels of performance. The sample consisted of 1152 difficulty scores concerning 288 individual routines, performed in the World Championships in 2013. The data were analysed using the mean absolute judge deviation from the final difficulty score, a Cronbach’s alpha coefficient and intra-class correlations, for consistency and reliability assessment. For validity assessment, mean deviations of judges’ difficulty scores, the Kendall’s coefficient of concordance W and ANOVA eta-squared values were calculated. Overall, the results in terms of consistency (Cronbach’s alpha mostly above 0.90) and reliability (intra-class correlations for single and average measures above 0.70 and 0.90, respectively) were satisfactory, in the first and third parts of the ranking on all apparatus. The medium level gymnasts, those in the second part of the ranking, had inferior reliability indices and highest score dispersion. In this part, the minimum of corrected item-total correlation of individual judges was 0.55, with most values well below, and the matrix for between-judge correlations identified remarkable inferior correlations. These findings suggest that the quality of difficulty judging in rhythmic gymnastics may be compromised at certain levels of performance. In future, special attention should be paid to the judging analysis of the medium level gymnasts, as well as the Code of Points applicability at this level. PMID:29339996
Predictive factors of difficulty in lower third molar extraction: A prospective cohort study.
Alvira-González, J; Figueiredo, R; Valmaseda-Castellón, E; Quesada-Gómez, C; Gay-Escoda, C
2017-01-01
Several publications have measured the difficulty of third molar removal, trying to establish the main risk factors, however several important preoperative and intraoperative variables are overlooked. A prospective cohort study comprising a total of 130 consecutive lower third molar extractions was performed. The outcome variables used to measure the difficulty of the extraction were operation time and a 100mm visual analogue scale filled by the surgeon at the end of the surgical procedure. The predictors were divided into 4 different groups (demographic, anatomic, radiographic and operative variables). A descriptive, bivariate and multivariate analysis of the data was performed. Patients' weight, the presence of bulbous roots, the need to perform crown and root sectioning of the lower third molar and Pell and Gregory 123 classification significantly influenced both outcome variables (p< 0.05). Certain anatomical, radiological and operative variables appear to be important factors in the assessment of surgical difficulty in the extraction of lower third molars.
Küper, Kristina; Gajewski, Patrick D; Frieg, Claudia; Falkenstein, Michael
2017-01-01
Executive functions are subject to a marked age-related decline, but have been shown to benefit from cognitive training interventions. As of yet, it is, however, still relatively unclear which neural mechanism can mediate training-related performance gains. In the present electrophysiological study, we examined the effects of multi-domain cognitive training on performance in an untrained cue-based task switch paradigm featuring Stroop color words: participants either had to indicate the word meaning of Stroop stimuli (word task) or perform the more difficult task of color naming (color task). One-hundred and three older adults (>65 years old) were randomly assigned to a training group receiving a 4-month multi-domain cognitive training, a passive no-contact control group or an active (social) control group receiving a 4-month relaxation training. For all groups, we recorded performance and EEG measures before and after the intervention. For the cognitive training group, but not for the two control groups, we observed an increase in response accuracy at posttest, irrespective of task and trial type. No training-related effects on reaction times were found. Cognitive training was also associated with an overall increase in N2 amplitude and a decrease of P2 latency on single trials. Training-related performance gains were thus likely mediated by an enhancement of response selection and improved access to relevant stimulus-response mappings. Additionally, cognitive training was associated with an amplitude decrease in the time window of the target-locked P3 at fronto-central electrodes. An increase in the switch positivity during advance task preparation emerged after both cognitive and relaxation training. Training-related behavioral and event-related potential (ERP) effects were not modulated by task difficulty. The data suggest that cognitive training increased slow negative potentials during target processing which enhanced the N2 and reduced a subsequent P3-like component on both switch and non-switch trials and irrespective of task difficulty. Our findings further corroborate the effectiveness of multi-domain cognitive training in older adults and indicate that ERPs can be instrumental in uncovering the neural processes underlying training-related performance gains.
ERIC Educational Resources Information Center
Engel-Yeger, Batya; Ziv-On, Daniella
2011-01-01
Sensory processing difficulties (SPD) are prevalent among children with ADHD. Yet, the question whether different SPD characterize children with different types of ADHD has not received enough attention in the literature. The current study characterized sensory processing difficulties (SPD) of children with different types of ADHD and explored the…
Ranking the Difficulty Level of the Knowledge Units Based on Learning Dependency
ERIC Educational Resources Information Center
Liu, Jun; Sha, Sha; Zheng, Qinghua; Zhang, Wei
2012-01-01
Assigning difficulty level indicators to the knowledge units helps the learners plan their learning activities more efficiently. This paper focuses on how to use the topology of a knowledge map to compute and rank the difficulty levels of knowledge units. Firstly, the authors present the hierarchical structure and properties of the knowledge map.…
ERIC Educational Resources Information Center
Salminen, Jonna; Koponen, Tuire; Räsänen, Pekka; Aro, Mikko
2015-01-01
Weaknesses in early number skills have been found to be a risk factor for later difficulties in mathematical performance. Nevertheless, only a few intervention studies with young children have been published. In this study, the responsiveness to early support in kindergarteners with most severe difficulties was examined with two different computer…
ERIC Educational Resources Information Center
Wang, Shinmin; Gathercole, Susan E.
2013-01-01
The current study investigated the cause of the reported problems in working memory in children with reading difficulties. Verbal and visuospatial simple and complex span tasks, and digit span and reaction times tasks performed singly and in combination, were administered to 46 children with single word reading difficulties and 45 typically…
ERIC Educational Resources Information Center
Heemskerk, Laura; Norman, Geoff; Chou, Sophia; Mintz, Marcy; Mandin, Henry; McLaughlin, Kevin
2008-01-01
Background: Previous studies have suggested an association between reasoning strategies and diagnostic success, but the influence on this relationship of variables such as question format and task difficulty, has not been studied. Our objective was to study the association between question format, task difficulty, reasoning strategies and…
Discovering Activities to Recognize and Track in a Smart Environment.
Rashidi, Parisa; Cook, Diane J; Holder, Lawrence B; Schmitter-Edgecombe, Maureen
2011-01-01
The machine learning and pervasive sensing technologies found in smart homes offer unprecedented opportunities for providing health monitoring and assistance to individuals experiencing difficulties living independently at home. In order to monitor the functional health of smart home residents, we need to design technologies that recognize and track activities that people normally perform as part of their daily routines. Although approaches do exist for recognizing activities, the approaches are applied to activities that have been pre-selected and for which labeled training data is available. In contrast, we introduce an automated approach to activity tracking that identifies frequent activities that naturally occur in an individual's routine. With this capability we can then track the occurrence of regular activities to monitor functional health and to detect changes in an individual's patterns and lifestyle. In this paper we describe our activity mining and tracking approach and validate our algorithms on data collected in physical smart environments.
Profiles and portfolios of adolescent school-based extracurricular activity participation.
Feldman, A F; Matjasko, J L
2007-04-01
The current study presented a new description of adolescent school-based activity participation, in the form of mutually exclusive activity portfolios, and described the kinds of youth that participate in each portfolio. These portfolios included (1) Sports Only, (2) Academics Only, (3) School Only, (4) Performance Only, (5) Multiple Activities, and (6) Non-Participation. Findings indicated that youth demographic characteristics and school size differentiated between different kinds of activity participation as well as nonparticipation. More detailed activity portfolios were also identified that were complex and demonstrate the difficulty of examining participation beyond larger, more inclusive groupings. The Multiple Activity portfolio emerged as a unique group worthy of further examination. Characteristics of non-participators included: lower socioeconomic status, lower grades, and attended larger schools. Hispanic adolescents were also less likely to participate in school-based extracurricular activities. Findings from this study inform ecological models of adolescent development as well as school and social policy.
ERIC Educational Resources Information Center
Shorkaee, Hossein Zabihi; Talebi, Seyed Hassan
2018-01-01
This study investigated the effects of Reading Strategy Instruction (RSI) on reading performance and attitude toward reading strategies while reading texts of different difficulty levels. Fifty-five university students studying Political and Basic Sciences took part in this study. After homogenizing the participants, 24 students were in the…
ERIC Educational Resources Information Center
Peretz, Arna S.; Shoham, Miriam
A study investigated the hypothesis that topic familiarity and assessed difficulty of a second language text correlated positively with performance on reading comprehension tests in languages for special purposes (LSP). Subjects were 177 advanced students of English as a Foreign Language (EFL) at Ben Gurion University (Israel). Faculty from the…
ERIC Educational Resources Information Center
Scheuneman, Janice Dowd; Gerritz, Kalle
1990-01-01
Differential item functioning (DIF) methodology for revealing sources of item difficulty and performance characteristics of different groups was explored. A total of 150 Scholastic Aptitude Test items and 132 Graduate Record Examination general test items were analyzed. DIF was evaluated for males and females and Blacks and Whites. (SLD)
ERIC Educational Resources Information Center
Stephanou, Georgia; Kyridis, Argyris
2012-01-01
This study examined (a) students' ability self-perceptions, perceptions of domain-difficulty, value beliefs, experienced emotions in lectures and performance in the courses taught by the perceived as extremely effective and ineffective teachers, (b) the role of ability self-perceptions, perceived domain-difficulty and value beliefs in the…
ERIC Educational Resources Information Center
Burns, Matthew K.; Maki, Kathrin E.; Karich, Abbey C.; Coolong-Chaffin, Melissa
2017-01-01
The current study used a multiple-baseline design to examine the effect of providing performance feedback on comprehension strategy use and reading comprehension. The participants were four seventh grade students with comprehension difficulties. The students were taught the reciprocal teaching comprehension strategies of generating questions,…
ERIC Educational Resources Information Center
Keller, Johannes
2007-01-01
Background: Stereotype threat research revealed that negative stereotypes can disrupt the performance of persons targeted by such stereotypes. This paper contributes to stereotype threat research by providing evidence that domain identification and the difficulty level of test items moderate stereotype threat effects on female students' maths…
Teachers' Difficulties in Preparation and Implementation of Performance Task
ERIC Educational Resources Information Center
Metin, Mustafa
2013-01-01
The aim of study is to determinate the difficulties of teachers in preparation and implementation of performance task. This study was carried out with 25 teachers (5 science and technology, 5 primary, 5 mathematic, 5 social science and 5 Turkish teachers) who working at elementary schools in Artvin. Sample of study is selected randomly. Case study…
Christensen, Mette K; O'Neill, Lotte; Hansen, Dorthe H; Norberg, Karen; Mortensen, Lene S; Charles, Peder
2016-02-22
The majority of studies on prevalence and characteristics of residents in difficulty have been conducted in English-speaking countries and the existing literature may not reflect the prevalence and characteristics of residents in difficulty in other parts of the world such as the Scandinavian countries, where healthcare systems are slightly different. The aim of this study was to examine prevalence and characteristics of residents in difficulty in one out of three postgraduate medical training regions in Denmark, and to produce both a quantifiable overview and in-depth understanding of the topic. We performed a mixed methods study. All regional residency program directors (N = 157) were invited to participate in an e-survey about residents in difficulty. Survey data were combined with database data on demographical characteristics of the background population (N = 2399) of residents, and analyzed statistically (Chi-squared test (Χ (2)) or Fisher's exact test). Secondly, we performed a qualitative interview study involving three focus group interviews with residency program directors. The analysis of the interview data employed qualitative content analysis. 73.2 % of the residency program directors completed the e-survey and 22 participated in the focus group interviews. The prevalence of residents in difficulty was 6.8 %. We found no statistically significant differences in the prevalence of residents in difficulty by gender and type of specialty. The results also showed two important themes related to the workplace culture of the resident in difficulty: 1) belated and inconsistent feedback on the resident's inadequate performance, and 2) the perceived culturally rooted priority of efficient patient care before education in the workplace. These two themes were emphasized by the program directors as the primary underlying causes of the residents' difficulty. More work is needed in order to clarify the link between, on the one hand, observable markers of residents in difficulty and, on the other hand, immanent processes and logics of practice in a healthcare system. From our perspective, further sociological and pedagogical investigations in educational cultures across settings and specialties could inform our understanding of and knowledge about pitfalls in residents' and doctors' socialization into the healthcare system.
Zhang, Hongxia; Chang, Lei; Chen, Xiaoying; Ma, Liang; Zhou, Renlai
2018-01-01
Working memory (WM) deficit is considered the key cause of learning difficulties (LDs). Studies have shown that WM is plastic and thus can be improved through training. This positive effect is transferable to fluid intelligence and academic performance. This study investigated whether WM updating ability and academic performance in children with LDs could be improved through WM updating training and explored the effects of this training on the children's brain activity. We used a running memory task lasting approximately 40 min per day for 28 days to train a group of 23 children with LDs (TLDs group). We also selected two control groups of 22 children with LDs (CLDs group) and 20 children without LDs (normal control [NC] group). The behavioral results of a pretest indicated that WM updating ability and academic performance in the TLDs and CLDs groups were significantly lower than those in the NC group before training. Compared with the CLDs group, the TLDs group exhibited significant performance improvement in a 2-back WM task, as well as in mathematical ability. Event-related potentials (ERPs) results suggested that the amplitudes of N160 (representative of visual recognition) and P300 (representative of updating processing, which is a valid index for updating WM) in the TLDs and CLDs groups were markedly lower than those in the NC group before training. In the TLDs group, these two components increased considerably after training, approaching levels similar to those in the NC group. The results of this study suggest that WM updating training can improve WM updating ability in children with LDs and the training effect can transfer to mathematical performance in such children. Furthermore, the participants' brain activity levels can exhibit positive changes. This article provides experimental evidence that WM updating training could mitigate the symptoms of LDs to a certain degree.
Weil, Joyce; Hutchinson, Susan R; Traxler, Karen
2014-11-01
Data from the Women's Health and Aging Study were used to test a model of factors explaining depressive symptomology. The primary purpose of the study was to explore the association between performance-based measures of functional ability and depression and to examine the role of self-rated physical difficulties and perceived instrumental support in mediating the relationship between performance-based functioning and depression. The inclusion of performance-based measures allows for the testing of functional ability as a clinical precursor to disability and depression: a critical, but rarely examined, association in the disablement process. Structural equation modeling supported the overall fit of the model and found an indirect relationship between performance-based functioning and depression, with perceived physical difficulties serving as a significant mediator. Our results highlight the complementary nature of performance-based and self-rated measures and the importance of including perception of self-rated physical difficulties when examining depression in older persons. © The Author(s) 2014.
Sufrinko, Alicia; Pearce, Kelly; Elbin, R J; Covassin, Tracey; Johnson, Eric; Collins, Michael; Kontos, Anthony P
2015-04-01
Researchers have reported that sleep duration is positively related to baseline neurocognitive performance. However, researchers have yet to examine the effect of preinjury sleep difficulties on postconcussion impairments. To compare neurocognitive impairment and symptoms of athletes with preinjury sleep difficulties to those without after a sport-related concussion (SRC). Cohort study; Level of evidence, 3. The sample included 348 adolescent and adult athletes (age, mean ± SD, 17.43 ± 2.34 years) with a diagnosed SRC. The sample was divided into 2 groups: (1) 34 (10%) participants with preinjury sleep difficulties (sleeping less as well as having trouble falling asleep; SLEEP SX) and (2) 231 (66%) participants without preinjury sleep difficulties (CONTROL). The remaining 84 (24%) participants with minimal sleep difficulties (1 symptom) were excluded. Participants completed the Immediate Postconcussion Assessment and Cognitive Test (ImPACT) and Postconcussion Symptom Scale (PCSS) at baseline and 3 postinjury intervals (2, 5-7, and 10-14 days after injury). A series of repeated-measures analyses of covariance with Bonferroni correction, controlling for baseline non-sleep-related symptoms, were conducted to compare postinjury neurocognitive performance between groups. Follow-up exploratory t tests examined between-group differences at each time interval. A series of analyses of variance were used to examine total PCSS score, sleep-related, and non-sleep-related symptoms across time intervals between groups. Groups differed significantly in PCSS scores across postinjury intervals for reaction time (P < .001), with the preinjury SLEEP SX group performing worse than controls at 5-7 days (mean ± SD, 0.70 ± 0.32 [SLEEP SX], 0.60 ± 0.14 [CONTROL]) and 10-14 days (0.61 ± 0.17 [SLEEP SX]; 0.57 ± 0.10 [CONTROL]) after injury. Groups also differed significantly on verbal memory performance (P = .04), with the SLEEP SX (68.21 ± 18.64) group performing worse than the CONTROL group (76.76 ± 14.50) 2 days after injury. The SLEEP SX group reported higher total symptom (P = .02) and sleep-related symptom (P = .02) scores across postinjury time intervals. Preinjury sleep difficulties may exacerbate neurocognitive impairment and symptoms after concussion. The findings may help clinicians identify athletes who are at risk for worse impairments after a concussion due to preinjury sleep difficulties. © 2015 The Author(s).
Fundamental movement skills and self-concept of children who are overweight.
Poulsen, Anne A; Desha, Laura; Ziviani, Jenny; Griffiths, Lisa; Heaslop, Annabel; Khan, Asad; Leong, Gary M
2011-06-01
Differences in fundamental movement skills and self-perceptions of physical ability and physical appearance of overweight and non-overweight children were investigated. Overweight (n = 89, mean age = 8.75 ± 1.4 years, BMI z-score = 2.22, SD = 0.46, 46% male) and non-overweight (n = 27, mean age = 8.25 ± 1.5 years, BMI z-score = 0.03, SD = 0.73, 62.1% male) participants enrolled in the KOALA (Kinder Overweight Activity Lifestyle Actions) project were included. The overall objective of the KOALA project was to determine in a randomized controlled trial the effect of a Triple P (Positive Parenting Program), and a family 'Eat Well Be Active' Scouts Camp program on BMI in overweight children. Baseline between-group differences on measures of fundamental movement skills and self-concept perceptions were analyzed using independent samples t-tests. Relationships between BMI and these variables were investigated with multiple linear regression. Overweight children had lower scores on Bruninks-Oseretsky Test of Motor Performance-2 subtests (Bilateral Coordination, Upper Limb Coordination, Strength, Balance, and Running Speed and Agility), and Physical abilities self-concept than non-overweight children. Children who were overweight had significant fundamental movement skill difficulties, as well as having poorer Physical abilities self-concept perceptions compared to non-overweight children. The association between increasing BMI and poor performance of gross motor tasks has potential implications for physical activity participation. Future research is needed to determine if fundamental movement skill difficulties and low physical ability self-concept are predisposing factors for children who are overweight or associated outcomes.
AUDIOVISUAL RESOURCES ON THE TEACHING PROCESS IN SURGICAL TECHNIQUE
PUPULIM, Guilherme Luiz Lenzi; IORIS, Rafael Augusto; GAMA, Ricardo Ribeiro; RIBAS, Carmen Australia Paredes Marcondes; MALAFAIA, Osvaldo; GAMA, Mirnaluci
2015-01-01
Background: The development of didactic means to create opportunities to permit complete and repetitive viewing of surgical procedures is of great importance nowadays due to the increasing difficulty of doing in vivo training. Thus, audiovisual resources favor the maximization of living resources used in education, and minimize problems arising only with verbalism. Aim: To evaluate the use of digital video as a pedagogical strategy in surgical technique teaching in medical education. Methods: Cross-sectional study with 48 students of the third year of medicine, when studying in the surgical technique discipline. They were divided into two groups with 12 in pairs, both subject to the conventional method of teaching, and one of them also exposed to alternative method (video) showing the technical details. All students did phlebotomy in the experimental laboratory, with evaluation and assistance of the teacher/monitor while running. Finally, they answered a self-administered questionnaire related to teaching method when performing the operation. Results: Most of those who did not watch the video took longer time to execute the procedure, did more questions and needed more faculty assistance. The total exposed to video followed the chronology of implementation and approved the new method; 95.83% felt able to repeat the procedure by themselves, and 62.5% of those students that only had the conventional method reported having regular capacity of technique assimilation. In both groups mentioned having regular difficulty, but those who have not seen the video had more difficulty in performing the technique. Conclusion: The traditional method of teaching associated with the video favored the ability to understand and transmitted safety, particularly because it is activity that requires technical skill. The technique with video visualization motivated and arouse interest, facilitated the understanding and memorization of the steps for procedure implementation, benefiting the students performance. PMID:26734790
Using near infrared spectroscopy and heart rate variability to detect mental overload.
Durantin, G; Gagnon, J-F; Tremblay, S; Dehais, F
2014-02-01
Mental workload is a key factor influencing the occurrence of human error, especially during piloting and remotely operated vehicle (ROV) operations, where safety depends on the ability of pilots to act appropriately. In particular, excessively high or low mental workload can lead operators to neglect critical information. The objective of the present study is to investigate the potential of functional near infrared spectroscopy (fNIRS) - a non-invasive method of measuring prefrontal cortex activity - in combination with measurements of heart rate variability (HRV), to predict mental workload during a simulated piloting task, with particular regard to task engagement and disengagement. Twelve volunteers performed a computer-based piloting task in which they were asked to follow a dynamic target with their aircraft, a task designed to replicate key cognitive demands associated with real life ROV operating tasks. In order to cover a wide range of mental workload levels, task difficulty was manipulated in terms of processing load and difficulty of control - two critical sources of workload associated with piloting and remotely operating a vehicle. Results show that both fNIRS and HRV are sensitive to different levels of mental workload; notably, lower prefrontal activation as well as a lower LF/HF ratio at the highest level of difficulty, suggest that these measures are suitable for mental overload detection. Moreover, these latter measurements point toward the existence of a quadratic model of mental workload. Copyright © 2013 Elsevier B.V. All rights reserved.
Mendes, Marcílio S; de Moraes, Josué
2014-11-01
In recent years, vector-borne and zoonotic diseases have become a major challenge for public health. Dengue fever and leptospirosis are the most important communicable diseases in Brazil based on their prevalence and the healthy life years lost from disability. The primary strategy for preventing human exposure to these diseases is effective insect and rodent control in and around the home. However, health authorities have difficulties in controlling vector-borne and zoonotic diseases because residents often refuse access to their homes. This study discusses aspects related to the activities performed by Brazilian health authorities to combat vector-borne and zoonotic diseases, particularly difficulties in relation to the legal aspect, which often impede the quick and effective actions of these professionals. How might it be possible to reconcile the need to preserve public health and the rule on the inviolability of the home, especially in the case of abandoned properties or illegal residents and the refusal of residents to allow the health authority access? Do residents have the right to hinder the performance of health workers even in the face of a significant and visible focus of disease transmission? This paper argues that a comprehensive legal plan aimed at the control of invasive vector-borne and zoonotic diseases including synanthropic animals of public health importance should be considered. In addition, this paper aims to bridge the gap between lawyers and public health professionals and to facilitate communication between them. Copyright © 2014 Elsevier B.V. All rights reserved.
Zhuang, Jie; Johnson, Micah A; Madden, David J; Burke, Deborah M; Diaz, Michele T
2016-12-01
Receptive language (e.g., reading) is largely preserved in the aging brain, and semantic processes in particular may continue to develop throughout the lifespan. We investigated the neural underpinnings of phonological and semantic retrieval in older and younger adults during receptive language tasks (rhyme and semantic similarity judgments). In particular, we were interested in the role of competition on language retrieval and varied the similarities between a cue, target, and distractor that were hypothesized to affect the mental process of competition. Behaviorally, all participants responded faster and more accurately during the rhyme task compared to the semantic task. Moreover, older adults demonstrated higher response accuracy than younger adults during the semantic task. Although there were no overall age-related differences in the neuroimaging results, an Age×Task interaction was found in left inferior frontal gyrus (IFG), with older adults producing greater activation than younger adults during the semantic condition. These results suggest that at lower levels of task difficulty, older and younger adults engaged similar neural networks that benefited behavioral performance. As task difficulty increased during the semantic task, older adults relied more heavily on largely left hemisphere language regions, as well as regions involved in perception and internal monitoring. Our results are consistent with the stability of language comprehension across the adult lifespan and illustrate how the preservation of semantic representations with aging may influence performance under conditions of increased task difficulty. Copyright © 2016 Elsevier Ltd. All rights reserved.
Association between Executive Function and Problematic Adolescent Driving
Pope, Caitlin N.; Ross, Lesley A.; Stavrinos, Despina
2016-01-01
Objective Motor vehicle collisions (MVCs) are one of the leading causes of injury and death for adolescents. Driving is a complex activity that is highly reliant on executive function to safely navigate through the environment. Little research has examined the efficacy of using self-reported executive function measures for assessing adolescent driving risk. This study examined the Behavior Rating Inventory of Executive Function (BRIEF) questionnaire and performance based-executive function tasks as potential predictors of problematic driving outcomes in adolescents. Methods Forty-six adolescent drivers completed the (1) BRIEF, (2) Trail Making Test (TMT), (3) Backwards Digit Span, and (4) self-report on three problematic driving outcomes: the number of times of having been pulled over by a police officer, the number of tickets issued, and the number of MVCs. Results Greater self-reported difficulty with planning and organization was associated with greater odds of having a MVC, while inhibition difficulties were associated with greater odds of receiving a ticket. Greater self-reported difficulty across multiple BRIEF subscales was associated with greater odds of being pulled over. Conclusion Overall findings indicated that the BRIEF, an ecological measure of executive function, showed significant association with self-reported problematic driving outcomes in adolescents. No relationship was found between performance-based executive function measures and self-reported driving outcomes. The BRIEF could offer unique and quick insight into problematic driving behavior and potentially be an indicator of driving risk in adolescent drivers during clinical evaluations. PMID:27661394
Effects of music engagement on responses to painful stimulation.
Bradshaw, David H; Chapman, C Richard; Jacobson, Robert C; Donaldson, Gary W
2012-06-01
We propose a theoretical framework for the behavioral modulation of pain based on constructivism, positing that task engagement, such as listening for errors in a musical passage, can establish a construction of reality that effectively replaces pain as a competing construction. Graded engagement produces graded reductions in pain as indicated by reduced psychophysiological arousal and subjective pain report. Fifty-three healthy volunteers having normal hearing participated in 4 music listening conditions consisting of passive listening (no task) or performing an error detection task varying in signal complexity and task difficulty. During all conditions, participants received normally painful fingertip shocks varying in intensity while stimulus-evoked potentials (SEP), pupil dilation responses (PDR), and retrospective pain reports were obtained. SEP and PDR increased with increasing stimulus intensity. Task performance decreased with increasing task difficulty. Mixed model analyses, adjusted for habituation/sensitization and repeated measures within person, revealed significant quadratic trends for SEP and pain report (Pchange<0.001) with large reductions from no task to easy task and smaller graded reductions corresponding to increasing task difficulty/complexity. PDR decreased linearly (Pchange<0.001) with graded task condition. We infer that these graded reductions in indicators of central and peripheral arousal and in reported pain correspond to graded increases in engagement in the music listening task. Engaging activities may prevent pain by creating competing constructions of reality that draw on the same processing resources as pain. Better understanding of these processes will advance the development of more effective pain modulation through improved manipulation of engagement strategies.
Niechwiej-Szwedo, Ewa; Alramis, Fatimah; Christian, Lisa W
2017-12-01
Performance of fine motor skills (FMS) assessed by a clinical test battery has been associated with reading achievement in school-age children. However, the nature of this association remains to be established. The aim of this study was to assess FMS in children with reading difficulties using two experimental tasks, and to determine if performance is associated with reduced binocular function. We hypothesized that in comparison to an age- and sex-matched control group, children identified with reading difficulties will perform worse only on a motor task that has been shown to rely on binocular input. To test this hypothesis, motor performance was assessed using two tasks: bead-threading and peg-board in 19 children who were reading below expected grade and age-level. Binocular vision assessment included tests for stereoacuity, fusional vergence, amplitude of accommodation, and accommodative facility. In comparison to the control group, children with reading difficulties performed significantly worse on the bead-threading task. In contrast, performance on the peg-board task was similar in both groups. Accommodative facility was the only measure of binocular function significantly associated with motor performance. Findings from our exploratory study suggest that normal binocular vision may provide an important sensory input for the optimal development of FMS and reading. Given the small sample size tested in the current study, further investigation to assess the contribution of binocular vision to the development and performance of FMS and reading is warranted. Copyright © 2017 Elsevier B.V. All rights reserved.
Ivanov, Iliyan; Liu, Xun; Clerkin, Suzanne; Schulz, Kurt; Fan, Jin; Friston, Karl; London, Edythe D; Schwartz, Jeffrey; Newcorn, Jeffrey H
2014-06-01
Psychostimulants, such as methylphenidate, are thought to improve information processing in motivation-reward and attention-activation networks by enhancing the effects of more relevant signals and suppressing those of less relevant ones; however the nature of such reciprocal influences remains poorly understood. To explore this question, we tested the effect of methylphenidate on performance and associated brain activity in the Anticipation, Conflict, Reward (ACR) task. Sixteen healthy adult volunteers, ages 21-45, were scanned twice using functional magnetic resonance imaging (fMRI) as they performed the ACR task under placebo and methylphenidate conditions. A three-way repeated measures analysis of variance, with cue (reward vs. non-reward), target (congruent vs. incongruent) and medication condition (methylphenidate vs. placebo) as the factors, was used to analyze behaviors on the task. Blood oxygen level dependent (BOLD) signals, reflecting task-related neural activity, were evaluated using linear contrasts. Participants exhibited significantly greater accuracy in the methylphenidate condition than the placebo condition. Compared with placebo, the methylphenidate condition also was associated with lesser task-related activity in components of attention-activation systems irrespective of the reward cue, and less task-related activity in components of the reward-motivation system, particularly the insula, during reward trials irrespective of target difficulty. These results suggest that methylphenidate enhances task performance by improving efficiency of information processing in both reward-motivation and in attention-activation systems. Published by Elsevier B.V.
Zhao, Yuanfang; Li, Jingguang; Liu, Xiqin; Song, Yiying; Wang, Ruosi; Yang, Zetian; Liu, Jia
2016-08-01
Individuals with developmental prosopagnosia (DP) exhibit severe difficulties in recognizing faces and to a lesser extent, also exhibit difficulties in recognizing non-face objects. We used fMRI to investigate whether these behavioral deficits could be accounted for by altered spontaneous neural activity. Two aspects of spontaneous neural activity were measured: the intensity of neural activity in a voxel indexed by the fractional amplitude of spontaneous low-frequency fluctuations (fALFF), and the connectivity of a voxel to neighboring voxels indexed by regional homogeneity (ReHo). Compared with normal adults, both the fALFF and ReHo values within the right occipital face area (rOFA) were significantly reduced in DP subjects. Follow-up studies on the normal adults revealed that these two measures indicated further functional division of labor within the rOFA. The fALFF in the rOFA was positively correlated with behavioral performance in recognition of non-face objects, whereas ReHo in the rOFA was positively correlated with processing of faces. When considered together, the altered fALFF and ReHo within the same region (rOFA) may account for the comorbid deficits in both face and object recognition in DPs, whereas the functional division of labor in these two measures helps to explain the relative independency of deficits in face recognition and object recognition in DP. Copyright © 2016 Elsevier Ltd. All rights reserved.
The use of an active controlled enclosure to attenuate sound radiation from a heavy radiator
NASA Astrophysics Data System (ADS)
Sun, Yao; Yang, Tiejun; Zhu, Minggang; Pan, Jie
2017-03-01
Active structural acoustical control usually experiences difficulty in the control of heavy sources or sources where direct applications of control forces are not practical. To overcome this difficulty, an active controlled enclosure, which forms a cavity with both flexible and open boundary, is employed. This configuration permits indirect implementation of active control in which the control inputs can be applied to subsidiary structures other than the sources. To determine the control effectiveness of the configuration, the vibro-acoustic behavior of the system, which consists of a top plate with an open, a sound cavity and a source panel, is investigated in this paper. A complete mathematical model of the system is formulated involving modified Fourier series formulations and the governing equations are solved using the Rayleigh-Ritz method. The coupling mechanisms of a partly opened cavity and a plate are analysed in terms of modal responses and directivity patterns. Furthermore, to attenuate sound power radiated from both the top panel and the open, two strategies are studied: minimizing the total radiated power and the cancellation of volume velocity. Moreover, three control configurations are compared, using a point force on the control panel (structural control), using a sound source in the cavity (acoustical control) and applying hybrid structural-acoustical control. In addition, the effects of boundary condition of the control panel on the sound radiation and control performance are discussed.
Powell, Sarah R.; Fuchs, Lynn S.
2014-01-01
According to national mathematics standards, algebra instruction should begin at kindergarten and continue through elementary school. Most often, teachers address algebra in the elementary grades with problems related to solving equations or understanding functions. With 789 2nd- grade students, we administered (a) measures of calculations and word problems in the fall and (b) an assessment of pre-algebraic reasoning, with items that assessed solving equations and functions, in the spring. Based on the calculation and word-problem measures, we placed 148 students into 1 of 4 difficulty status categories: typically performing, calculation difficulty, word-problem difficulty, or difficulty with calculations and word problems. Analyses of variance were conducted on the 148 students; path analytic mediation analyses were conducted on the larger sample of 789 students. Across analyses, results corroborated the finding that word-problem difficulty is more strongly associated with difficulty with pre-algebraic reasoning. As an indicator of later algebra difficulty, word-problem difficulty may be a more useful predictor than calculation difficulty, and students with word-problem difficulty may require a different level of algebraic reasoning intervention than students with calculation difficulty. PMID:25309044
Effect of time span and task load on pilot mental workload
NASA Technical Reports Server (NTRS)
Berg, S. L.; Sheridan, T. B.
1985-01-01
Two sets of experiments were run to examine how the mental workload of a pilot might be measured. The effects of continuous manual control activity versus discrete assigned mental tasks (including the length of time between receiving an assignment and executing it) were examined. The first experiment evaluated the strengths and weaknesses of measuring mental workload with an objective perforamance (altitude deviations) and five subjective ratings (activity level, complexity, difficulty, stress, and workload). The second set of experiments built upon the first set by increasing workload intensities and adding another performance measure: airspeed deviation. The results are discussed for both low and high experience pilots.
Embedded assessment algorithms within home-based cognitive computer game exercises for elders.
Jimison, Holly; Pavel, Misha
2006-01-01
With the recent consumer interest in computer-based activities designed to improve cognitive performance, there is a growing need for scientific assessment algorithms to validate the potential contributions of cognitive exercises. In this paper, we present a novel methodology for incorporating dynamic cognitive assessment algorithms within computer games designed to enhance cognitive performance. We describe how this approach works for variety of computer applications and describe cognitive monitoring results for one of the computer game exercises. The real-time cognitive assessments also provide a control signal for adapting the difficulty of the game exercises and providing tailored help for elders of varying abilities.
Patched bimetallic surfaces are active catalysts for ammonia decomposition.
Guo, Wei; Vlachos, Dionisios G
2015-10-07
Ammonia decomposition is often used as an archetypical reaction for predicting new catalytic materials and understanding the very reason of why some reactions are sensitive on material's structure. Core-shell or surface-segregated bimetallic nanoparticles expose outstanding activity for many heterogeneously catalysed reactions but the reasons remain elusive owing to the difficulties in experimentally characterizing active sites. Here by performing multiscale simulations in ammonia decomposition on various nickel loadings on platinum (111), we show that the very high activity of core-shell structures requires patches of the guest metal to create and sustain dual active sites: nickel terraces catalyse N-H bond breaking and nickel edge sites drive atomic nitrogen association. The structure sensitivity on these active catalysts depends profoundly on reaction conditions due to kinetically competing relevant elementary reaction steps. We expose a remarkable difference in active sites between transient and steady-state studies and provide insights into optimal material design.
Patched bimetallic surfaces are active catalysts for ammonia decomposition
NASA Astrophysics Data System (ADS)
Guo, Wei; Vlachos, Dionisios G.
2015-10-01
Ammonia decomposition is often used as an archetypical reaction for predicting new catalytic materials and understanding the very reason of why some reactions are sensitive on material's structure. Core-shell or surface-segregated bimetallic nanoparticles expose outstanding activity for many heterogeneously catalysed reactions but the reasons remain elusive owing to the difficulties in experimentally characterizing active sites. Here by performing multiscale simulations in ammonia decomposition on various nickel loadings on platinum (111), we show that the very high activity of core-shell structures requires patches of the guest metal to create and sustain dual active sites: nickel terraces catalyse N-H bond breaking and nickel edge sites drive atomic nitrogen association. The structure sensitivity on these active catalysts depends profoundly on reaction conditions due to kinetically competing relevant elementary reaction steps. We expose a remarkable difference in active sites between transient and steady-state studies and provide insights into optimal material design.
Roijendijk, Linsey; Farquhar, Jason; van Gerven, Marcel; Jensen, Ole; Gielen, Stan
2013-01-01
Objective Covert visual spatial attention is a relatively new task used in brain computer interfaces (BCIs) and little is known about the characteristics which may affect performance in BCI tasks. We investigated whether eccentricity and task difficulty affect alpha lateralization and BCI performance. Approach We conducted a magnetoencephalography study with 14 participants who performed a covert orientation discrimination task at an easy or difficult stimulus contrast at either a near (3.5°) or far (7°) eccentricity. Task difficulty was manipulated block wise and subjects were aware of the difficulty level of each block. Main Results Grand average analyses revealed a significantly larger hemispheric lateralization of posterior alpha power in the difficult condition than in the easy condition, while surprisingly no difference was found for eccentricity. The difference between task difficulty levels was significant in the interval between 1.85 s and 2.25 s after cue onset and originated from a stronger decrease in the contralateral hemisphere. No significant effect of eccentricity was found. Additionally, single-trial classification analysis revealed a higher classification rate in the difficult (65.9%) than in the easy task condition (61.1%). No effect of eccentricity was found in classification rate. Significance Our results indicate that manipulating the difficulty of a task gives rise to variations in alpha lateralization and that using a more difficult task improves covert visual spatial attention BCI performance. The variations in the alpha lateralization could be caused by different factors such as an increased mental effort or a higher visual attentional demand. Further research is necessary to discriminate between them. We did not discover any effect of eccentricity in contrast to results of previous research. PMID:24312477
Roijendijk, Linsey; Farquhar, Jason; van Gerven, Marcel; Jensen, Ole; Gielen, Stan
2013-01-01
Covert visual spatial attention is a relatively new task used in brain computer interfaces (BCIs) and little is known about the characteristics which may affect performance in BCI tasks. We investigated whether eccentricity and task difficulty affect alpha lateralization and BCI performance. We conducted a magnetoencephalography study with 14 participants who performed a covert orientation discrimination task at an easy or difficult stimulus contrast at either a near (3.5°) or far (7°) eccentricity. Task difficulty was manipulated block wise and subjects were aware of the difficulty level of each block. Grand average analyses revealed a significantly larger hemispheric lateralization of posterior alpha power in the difficult condition than in the easy condition, while surprisingly no difference was found for eccentricity. The difference between task difficulty levels was significant in the interval between 1.85 s and 2.25 s after cue onset and originated from a stronger decrease in the contralateral hemisphere. No significant effect of eccentricity was found. Additionally, single-trial classification analysis revealed a higher classification rate in the difficult (65.9%) than in the easy task condition (61.1%). No effect of eccentricity was found in classification rate. Our results indicate that manipulating the difficulty of a task gives rise to variations in alpha lateralization and that using a more difficult task improves covert visual spatial attention BCI performance. The variations in the alpha lateralization could be caused by different factors such as an increased mental effort or a higher visual attentional demand. Further research is necessary to discriminate between them. We did not discover any effect of eccentricity in contrast to results of previous research.
Horowitz-Kraus, Tzipi; DiFrancesco, Mark; Kay, Benjamin; Wang, Yingying; Holland, Scott K.
2015-01-01
The Reading Acceleration Program, a computerized reading-training program, increases activation in neural circuits related to reading. We examined the effect of the training on the functional connectivity between independent components related to visual processing, executive functions, attention, memory, and language during rest after the training. Children 8–12 years old with reading difficulties and typical readers participated in the study. Behavioral testing and functional magnetic resonance imaging were performed before and after the training. Imaging data were analyzed using an independent component analysis approach. After training, both reading groups showed increased single-word contextual reading and reading comprehension scores. Greater positive correlations between the visual-processing component and the executive functions, attention, memory, or language components were found after training in children with reading difficulties. Training-related increases in connectivity between the visual and attention components and between the visual and executive function components were positively correlated with increased word reading and reading comprehension, respectively. Our findings suggest that the effect of the Reading Acceleration Program on basic cognitive domains can be detected even in the absence of an ongoing reading task. PMID:26199874
Horowitz-Kraus, Tzipi; DiFrancesco, Mark; Kay, Benjamin; Wang, Yingying; Holland, Scott K
2015-01-01
The Reading Acceleration Program, a computerized reading-training program, increases activation in neural circuits related to reading. We examined the effect of the training on the functional connectivity between independent components related to visual processing, executive functions, attention, memory, and language during rest after the training. Children 8-12 years old with reading difficulties and typical readers participated in the study. Behavioral testing and functional magnetic resonance imaging were performed before and after the training. Imaging data were analyzed using an independent component analysis approach. After training, both reading groups showed increased single-word contextual reading and reading comprehension scores. Greater positive correlations between the visual-processing component and the executive functions, attention, memory, or language components were found after training in children with reading difficulties. Training-related increases in connectivity between the visual and attention components and between the visual and executive function components were positively correlated with increased word reading and reading comprehension, respectively. Our findings suggest that the effect of the Reading Acceleration Program on basic cognitive domains can be detected even in the absence of an ongoing reading task.
[Play therapy in social work with children].
Dvarionas, Dziugas
2002-01-01
This article introduces the results of scientific research performed in 1995-1997 in Kaunas primary school with 1st and 2nd grade children exhibiting behavioral disorders. Play therapy, a quite novel method in the country, seeks better improvement and an achievement of a better relationship for disadvantaged children in educational process. Play group counseling, or play media counseling, is shown as an important method in working with early primary grade children, especially those who present behavioral problems in the classroom. Another important aspect of group play therapy is the concentrated relationship with the counselor. Primary school children, especially those who are disadvantaged respond more to warmth than to praise for being right and doing well. Data analysis allow us to assume that behavioral difficulties of primary school children are connected with a low rate of self-esteem and dissatisfaction with their vital activities. Main conclusions to correspond with hypothesis held for the research are: a) children exhibiting behavioral problems are less active in educational process; b) by means of systematic use of play group counseling method in school, problematic children are able to solve their difficulties and to optimize their academic improvement; c) there is a complementary relationship between child's self-esteem and his/her satisfaction with his/her vital activity.
Underlying mechanisms of writing difficulties among children with neurofibromatosis type 1.
Gilboa, Yafit; Josman, Naomi; Fattal-Valevski, Aviva; Toledano-Alhadef, Hagit; Rosenblum, Sara
2014-06-01
Writing is a complex activity in which lower-level perceptual-motor processes and higher-level cognitive processes continuously interact. Preliminary evidence suggests that writing difficulties are common to children with Neurofibromatosis type 1 (NF1). The aim of this study was to compare the performance of children with and without NF1 in lower (visual perception, motor coordination and visual-motor integration) and higher processes (verbal and performance intelligence, visual spatial organization and visual memory) required for intact writing; and to identify the components that predict the written product's spatial arrangement and content among children with NF1. Thirty children with NF1 (ages 8-16) and 30 typically developing children matched by gender and age were tested, using standardized assessments. Children with NF1 had a significantly inferior performance in comparison to control children, on all tests that measured lower and higher level processes. The cognitive planning skill was found as a predictor of the written product's spatial arrangement. The verbal intelligence predicted the written content level. Results suggest that high level processes underlie the poor quality of writing product in children with NF1. Treatment approaches for children with NF1 must include detailed assessments of cognitive planning and language skills. Copyright © 2014 Elsevier Ltd. All rights reserved.
Differences in Self-Reported Physical Limitation Among Older Women and Men in Ismailia, Egypt
2012-01-01
Objectives. This study explores the reasons for gender differences in self-reported physical limitation among older adults in Ismailia, Egypt. Method. 435 women and 448 men, 50 years and older in Ismailia, Egypt, participated in a social survey and tests of physical performance. Ordered logit models were estimated to compare unadjusted gender differences in reported disability with these differences adjusted sequentially for (a) age and objective measures of physical performance, (b) self-reported morbidities and health care use, and (c) social and economic attributes. Results. Compared with men, women more often reported higher levels of limitation in activities of daily living (ADLs), upper-extremity range of motion (ROM), and lower-extremity gross mobility (GM). Adjusting for age and objective measures of physical performance, women and men had similar odds of self-reporting difficulty with ADLs. With sequential adjustments for the remaining variables, women maintained significantly higher odds of self-reported difficulty with upper-extremity ROM and lower-extremity GM. Discussion. Cross-culturally, gender differences in self-reported disability may arise from objective and subjective perceptions of disability. Collectively, these results and those from prior studies in Bangladesh and the United States suggest that gender gaps in self-reported physical limitation may be associated with the degree of gender equality in society. PMID:22929399
Differences in self-reported physical limitation among older women and men in Ismailia, Egypt.
Khadr, Zeinab; Yount, Kathryn
2012-09-01
This study explores the reasons for gender differences in self-reported physical limitation among older adults in Ismailia, Egypt. 435 women and 448 men, 50 years and older in Ismailia, Egypt, participated in a social survey and tests of physical performance. Ordered logit models were estimated to compare unadjusted gender differences in reported disability with these differences adjusted sequentially for (a) age and objective measures of physical performance, (b) self-reported morbidities and health care use, and (c) social and economic attributes. Compared with men, women more often reported higher levels of limitation in activities of daily living (ADLs), upper-extremity range of motion (ROM), and lower-extremity gross mobility (GM). Adjusting for age and objective measures of physical performance, women and men had similar odds of self-reporting difficulty with ADLs. With sequential adjustments for the remaining variables, women maintained significantly higher odds of self-reported difficulty with upper-extremity ROM and lower-extremity GM. Cross-culturally, gender differences in self-reported disability may arise from objective and subjective perceptions of disability. Collectively, these results and those from prior studies in Bangladesh and the United States suggest that gender gaps in self-reported physical limitation may be associated with the degree of gender equality in society.
Warm-up before laparoscopic surgery is not essential.
Weston, Maree K; Stephens, Jacqueline H; Schafer, Amy; Hewett, Peter J
2014-03-01
Several recent studies have suggested that warming up prior to surgery may improve surgical performance. The purpose of this study was to investigate whether warming up prior to laparoscopic surgery improves surgical performance or reduces surgery duration. Between August 2011 and January 2012, a randomized controlled trial was conducted to compare two warm-up modalities to no warm-up. The study was conducted at a single site, with nine surgeons performing 72 laparoscopic cholecystectomies and 37 laparoscopic appendicectomies. Prior to surgery, surgeons were randomized to either laparoscopic trainer box warm-up, PlayStation 2 warm-up or no warm-up. The activity was performed within 30 min of surgery commencing. Patients provided informed consent for the surgery to be digitally recorded. Digital videodiscs (DVDs) were reviewed by an independent and blinded assessor. Data were collected on duration of surgery, level of training and perceived surgical difficulty. Surgical performance was graded using a validated scoring system. From the 109 operations performed, there were 75 usable DVDs. Overall, there were no statistical differences in the demographics of patients and surgeons in the three treatment groups, nor in the subset that had useable DVDs. There were no statistical differences in the duration of surgery or surgeon's perceived surgical difficulty. There was no statistical difference in surgical performance. This study suggests that warm-up prior to laparoscopic cholecystectomy or appendicectomy is not essential, acknowledging that there are several study limitations that preclude definitive conclusion. © 2012 The Authors. ANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons.
Amir, Ofra; Amir, Dor; Shahar, Yuval; Hart, Yuval; Gal, Kobi
2018-01-01
Demonstrability-the extent to which group members can recognize a correct solution to a problem-has a significant effect on group performance. However, the interplay between group size, demonstrability and performance is not well understood. This paper addresses these gaps by studying the joint effect of two factors-the difficulty of solving a problem and the difficulty of verifying the correctness of a solution-on the ability of groups of varying sizes to converge to correct solutions. Our empirical investigations use problem instances from different computational complexity classes, NP-Complete (NPC) and PSPACE-complete (PSC), that exhibit similar solution difficulty but differ in verification difficulty. Our study focuses on nominal groups to isolate the effect of problem complexity on performance. We show that NPC problems have higher demonstrability than PSC problems: participants were significantly more likely to recognize correct and incorrect solutions for NPC problems than for PSC problems. We further show that increasing the group size can actually decrease group performance for some problems of low demonstrability. We analytically derive the boundary that distinguishes these problems from others for which group performance monotonically improves with group size. These findings increase our understanding of the mechanisms that underlie group problem-solving processes, and can inform the design of systems and processes that would better facilitate collective decision-making.
ERIC Educational Resources Information Center
Tang, Thomas Li-Ping; Reynolds, David B.
1993-01-01
Fifty-two subjects competed on a task against themselves, a difficult competitor, and an easy competitor. Certainty, ability attribution, and task satisfaction for those with low self-esteem were affected by perceived goal difficulty but not for those with high self-esteem. Low self-esteem groups had lower goals, certainty, and task performance.…
ERIC Educational Resources Information Center
Scott, Fraser J.
2012-01-01
Mathematical ability is a major contributory factor to the success of a student in any science course. This paper aims to determine the source of the difficulty that students often find when performing calculations in chemistry. Through the design and analysis of a set of chemistry questions and analogous mathematics questions, set in a Standard…
ERIC Educational Resources Information Center
Filippatou, Diamanto; Kaldi, Stavroula
2010-01-01
This study focuses upon the effectiveness of project-based learning on primary school pupils with learning difficulties regarding their academic performance and attitudes towards self efficacy, task value, group work and teaching methods applied. The present study is a part of a larger one that included six Greek fourth-grade primary school…
Ruocco, Anthony C; Lam, Jaeger; McMain, Shelley F
2014-01-01
Objective: To examine the contributions of subjective cognitive complaints to functional disability in patients with borderline personality disorder (BPD) and their nonaffected relatives. Method: Patients with BPD (n = 26), their first-degree biological relatives (n = 17), and nonpsychiatric control subjects (n = 31) completed a self-report measure of cognitive difficulties and rated the severity of their functional disability on the World Health Organization Disability Assessment Schedule 2.0. Results: After accounting for group differences in age and severity of depressive symptoms, patients and relatives endorsed more inattention and memory problems than control subjects. Whereas probands reported greater disability than relatives and control subjects across all functional domains, relatives described more difficulties than control subjects in managing multiple life activities, including domestic activities and occupational and academic functioning, and participating in society. For both probands and relatives, inattention and memory problems were linked primarily to difficulties with life activities, independent of depression and other comorbid psychiatric disorders. Conclusions: Problems with inattention and forgetfulness may lead to difficulties carrying out activities of daily living and occupational or academic problems in patients with BPD, as well as their nonaffected first-degree relatives. PMID:25007408
Ruocco, Anthony C; Lam, Jaeger; McMain, Shelley F
2014-06-01
To examine the contributions of subjective cognitive complaints to functional disability in patients with borderline personality disorder (BPD) and their nonaffected relatives. Patients with BPD (n = 26), their first-degree biological relatives (n = 17), and nonpsychiatric control subjects (n = 31) completed a self-report measure of cognitive difficulties and rated the severity of their functional disability on the World Health Organization Disability Assessment Schedule 2.0. After accounting for group differences in age and severity of depressive symptoms, patients and relatives endorsed more inattention and memory problems than control subjects. Whereas probands reported greater disability than relatives and control subjects across all functional domains, relatives described more difficulties than control subjects in managing multiple life activities, including domestic activities and occupational and academic functioning, and participating in society. For both probands and relatives, inattention and memory problems were linked primarily to difficulties with life activities, independent of depression and other comorbid psychiatric disorders. Problems with inattention and forgetfulness may lead to difficulties carrying out activities of daily living and occupational or academic problems in patients with BPD, as well as their nonaffected first-degree relatives.
Pomplun, M; Reingold, E M; Shen, J
2001-09-01
In three experiments, participants' visual span was measured in a comparative visual search task in which they had to detect a local match or mismatch between two displays presented side by side. Experiment 1 manipulated the difficulty of the comparative visual search task by contrasting a mismatch detection task with a substantially more difficult match detection task. In Experiment 2, participants were tested in a single-task condition involving only the visual task and a dual-task condition in which they concurrently performed an auditory task. Finally, in Experiment 3, participants performed two dual-task conditions, which differed in the difficulty of the concurrent auditory task. Both the comparative search task difficulty (Experiment 1) and the divided attention manipulation (Experiments 2 and 3) produced strong effects on visual span size.
Self-reported learning difficulties and dietary intake in Norwegian adolescents.
Øverby, Nina Cecilie; Lüdemann, Eva; Høigaard, Rune
2013-11-01
The academic performance of children impacts future educational attainment which may increase socioeconomic status which again influences their health. One of several factors that might affect academic performance is the diet. The aim of this study was to investigate the cross sectional relation between diet and self-reported reading-, writing-, and mathematical difficulties in Norwegian adolescents. In total, 475 ninth- and tenth-grade students out of 625 eligible ones from four different secondary schools in three different municipalities in Vest-Agder County, Norway, participated, giving a participation rate of 77%. The students filled in a questionnaire with food frequency questions of selected healthy and unhealthy food items, questions of meal frequency and different learning difficulties. Regular breakfast was significantly associated with decreased odds of both writing and reading difficulties (OR: 0.44 (0.2-0.8), p = 0.01) and mathematical difficulties (OR: 0.33 (0.2-0.6), p ≤ 0.001). In addition, having lunch, dinner and supper regularly were associated with decreased odds of mathematical difficulties. Further, a high intake of foods representing a poor diet (sugar-sweetened soft drinks, sweets, chocolate, savory snacks, pizza and hot dogs) was significantly associated with increased odds of mathematical difficulties. Having a less-frequent intake of unhealthy foods and not skipping meals are associated with decreased odds of self-reported learning difficulties in Norwegian adolescents in this study. The results of this study support the need for a larger study with a more representative sample.
Burger, Lucile; Uittenhove, Kim; Lemaire, Patrick; Taconnat, Laurence
2017-04-01
Efficient execution of strategies is crucial to memory performance and to age-related differences in this performance. Relative strategy complexity influences memory performance and aging effects on memory. Here, we aimed to further our understanding of the effects of relative strategy complexity by looking at the role of cognitive control functions and the time-course of the effects of relative strategy complexity. Thus, we manipulated inter-stimulus intervals (ISI) and assessed executive functions. Results showed that (a) performance as a function of the relative strategy difficulty of the current and previous trial was modulated by ISI, (b) these effects were modulated by inhibition capacities, and (c) significant age differences were found in the way ISI modulates relative strategy difficulty. These findings have important implications for understanding the relationships between aging, executive control, and strategy execution in episodic memory. Copyright © 2017 Elsevier B.V. All rights reserved.
Swenor, Bonnielin K; Bandeen-Roche, Karen; Muñoz, Beatriz; West, Sheila K
2014-08-01
To determine whether performance speeds mediate the association between visual impairment and self-reported mobility disability over an 8-year period. Longitudinal analysis. Salisbury, Maryland. Salisbury Eye Evaluation Study participants aged 65 and older (N=2,520). Visual impairment was defined as best-corrected visual acuity worse than 20/40 in the better-seeing eye or visual field less than 20°. Self-reported mobility disability on three tasks was assessed: walking up stairs, walking down stairs, and walking 150 feet. Performance speed on three similar tasks was measured: walking up steps (steps/s), walking down steps (steps/s), and walking 4 m (m/s). For each year of observation, the odds of reporting mobility disability was significantly greater for participants who were visually impaired (VI) than for those who were not (NVI) (odds ratio (OR) difficulty walking up steps=1.58, 95% confidence interval (CI)=1.32-1.89; OR difficulty walking down steps=1.90, 95% CI=1.59-2.28; OR difficulty walking 150 feet=2.11, 95% CI=1.77-2.51). Once performance speed on a similar mobility task was included in the models, VI participants were no longer more likely to report mobility disability than those who were NVI (OR difficulty walking up steps=0.84, 95% CI=0.65-1.11; OR difficulty walking down steps=0.96, 95% CI=0.74-1.24; OR difficulty walking 150 feet=1.22, 95% CI=0.98-1.50). Slower performance speed in VI individuals largely accounted for the difference in the odds of reporting mobility disability, suggesting that VI older adults walk slower and are therefore more likely to report mobility disability than those who are NVI. Improving mobility performance in older adults with visual impairment may minimize the perception of mobility disability. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.
Pinto, Serge; Mancini, Laura; Jahanshahi, Marjan; Thornton, John S; Tripoliti, Elina; Yousry, Tarek A; Limousin, Patricia
2011-10-01
Among the repertoire of motor functions, although hand movement and speech production tasks have been investigated widely by functional neuroimaging, paradigms combining both movements have been studied less so. Such paradigms are of particular interest in Parkinson's disease, in which patients have specific difficulties performing two movements simultaneously. In 9 unmedicated patients with Parkinson's disease and 15 healthy control subjects, externally cued tasks (i.e., hand movement, speech production, and combined hand movement and speech production) were performed twice in a random order and functional magnetic resonance imaging detected cerebral activations, compared to the rest. F-statistics tested within-group (significant activations at P values < 0.05, familywise error corrected), between-group, and between-task comparisons (regional activations significant at P values < 0.001, uncorrected, with cluster size > 10 voxels). For control subjects, the combined task activations comprised the sum of those obtained during hand movement and speech production performed separately, reflecting the neural correlates of performing movements sharing similar programming modalities. In patients with Parkinson's disease, only activations underlying hand movement were observed during the combined task. We interpreted this phenomenon as patients' potential inability to recruit facilitatory activations while performing two movements simultaneously. This lost capacity could be related to a functional prioritization of one movement (i.e., hand movement), in comparison with the other (i.e., speech production). Our observation could also reflect the inability of patients with Parkinson's disease to intrinsically engage the motor coordination necessary to perform a combined task. Copyright © 2011 Movement Disorder Society.
Improvement in motor performance of Weaver mutant mice following lesions of the cerebellum.
Grüsser, C; Grüsser-Cornehls, U
1998-12-01
In Weaver mutants (B6CBA wv/wv) cerebellar granule cells degenerate almost completely postnatally. A partial loss of Purkinje cells (PC) and a degeneration of dopaminergic cells in the substantia nigra have also been found. Weaver mice suffer from striking motor symptoms, including difficulty in walking without toppling over. In an attempt to influence the poor motor performance, the cerebellum in young animals was removed, thus eliminating the faulty output of surviving PCs, demonstrated electrophysiologically. Unoperated Weaver, lesioned wildtypes and one sham mouse were used as controls. Before and after operation, a battery of behavioural tests was performed. In Weaver mice, tumbling to the side (t) and the relation of t to the motor activity (k) while traversing an open-field matrix, (t/k), improved considerably, as did manoeuvring on a slanted wire mesh, but keeping balance on a wooden bench did not to the same degree. Locomotor activity alone improved in some animals. In wildtypes no significant changes occurred after operation, with the exception of a strong reduction in locomotor activity. The experiments demonstrate that the motor performance in Weaver mutant mice benefits from removal of their cerebellum.
Jerome, Gerald J; Glass, Thomas A; Mielke, Michelle; Xue, Qian-Li; Andersen, Ross E; Fried, Linda P
2006-11-01
Physical activity is important for maintaining functional independence of older persons, especially for those with existing functional deficits. Since such deficits may pose barriers to activity, it would be instructive to examine activity patterns in relation to specific types of deficits to determine the amount and type of physical activity older women pursue. This study sought to identify categories of functional deficits associated with activity levels and evaluated the potential for older women to increase their physical activity levels. Community-dwelling women, aged 70-79 years, from the Women's Health and Aging Studies I and II (N = 710), were assessed for self-reported physical activity, functional deficits and chronic conditions, along with objective measures of muscle strength. Both type (household chores, exercise, and recreational activity) and amount of physical activity (min/wk) were examined. Meeting physical activity recommendations was defined as > or =150 minutes per week of moderate intensity physical activity, and inactivity was defined as no weekly moderate intensity physical activity. Hierarchical categories of functional deficits were based on self-reported difficulty in four functional domains (i.e., mobility/exercise tolerance, upper extremity, higher functioning, and self-care), and self-reports ranged from no difficulty to difficulty in all four domains. The prevalence of inactivity and meeting activity recommendations were 14.4% and 12.7%, respectively. Severity of functional deficits was associated with increased risk of inactivity (adjusted odds ratios [ORs(adj)] = 3.14-17.61) and reduced likelihood of meeting activity recommendations (ORs(adj) =.11-.40). Even among those with higher functioning or self-care difficulties, 30% reported walking for exercise. There was evidence that older women with functional deficits can remain physically active. However, for some of these women, meeting the recommended levels of activity may be unrealistic. Efforts to increase physical activity levels among older adults should include treatment or management of functional deficits, chronic conditions, and poor strength.
Mathiassen, Svend Erik; Hallman, David M.; Lyskov, Eugene; Hygge, Staffan
2014-01-01
Neurophysiologic theory and some empirical evidence suggest that fatigue caused by physical work may be more effectively recovered during “diverting” periods of cognitive activity than during passive rest; a phenomenon of great interest in working life. We investigated the extent to which development and recovery of fatigue during repeated bouts of an occupationally relevant reaching task was influenced by the difficulty of a cognitive activity between these bouts. Eighteen male volunteers performed three experimental sessions, consisting of six 7-min bouts of reaching alternating with 3 minutes of a memory test differing in difficulty between sessions. Throughout each session, recordings were made of upper trapezius muscle activity using electromyography (EMG), heart rate and heart rate variability (HRV) using electrocardiography, arterial blood pressure, and perceived fatigue (Borg CR10 scale and SOFI). A test battery before, immediately after and 1 hour after the work period included measurements of maximal shoulder elevation strength (MVC), pressure pain threshold (PPT) over the trapezius muscles, and a submaximal isometric contraction. As expected, perceived fatigue and EMG amplitude increased during the physical work bouts. Recovery did occur between the bouts, but fatigue accumulated throughout the work period. Neither EMG changes nor recovery of perceived fatigue during breaks were influenced by cognitive task difficulty, while heart rate and HRV recovered the most during breaks with the most difficult task. Recovery of perceived fatigue after the 1 hour work period was also most pronounced for the most difficult cognitive condition, while MVC and PPT showed ambiguous patterns, and EMG recovered similarly after all three cognitive protocols. Thus, we could confirm that cognitive tasks between bouts of fatiguing physical work can, indeed, accelerate recovery of some factors associated with fatigue, even if benefits may be moderate and some responses may be equivocal. Our results encourage further research into combinations of physical and mental tasks in an occupational context. PMID:25375644
Scaffolding for solving problem in static fluid: A case study
NASA Astrophysics Data System (ADS)
Koes-H, Supriyono; Muhardjito, Wijaya, Charisma P.
2018-01-01
Problem solving is one of the basic abilities that should be developed from learning physics. However, students still face difficulties in the process of non-routine problem-solving. Efforts are necessary to be taken in order to identify such difficulties and the solutions to solve them. An effort in the form of a diagnosis of students' performance in problem solving can be taken to identify their difficulties, and various instructional scaffolding supports can be utilized to eliminate the difficulties. This case study aimed to describe the students' difficulties in solving static fluid problems and the effort to overcome such difficulties through different scaffolding supports. The research subjects consisted of four 10-grade students of (Public Senior High School) SMAN 4 Malang selected by purposive sampling technique. The data of students' difficulties were collected via think-aloud protocol implemented on students' performance in solving non-routine static fluid problems. Subsequently, combined scaffolding supports were given to the students based on their particular difficulties. The research findings pointed out that there were several conceptual difficulties discovered from the students when solving static fluid problems, i.e. the use of buoyancy force formula, determination of all forces acting on a plane in a fluid, the resultant force on a plane in a fluid, and determination of a plane depth in a fluid. An effort that can be taken to overcome such conceptual difficulties is providing a combination of some appropriate scaffolding supports, namely question prompts with specific domains, simulation, and parallel modeling. The combination can solve students' lack of knowledge and improve their conceptual understanding, as well as help them to find solutions by linking the problems with their prior knowledge. According to the findings, teachers are suggested to diagnose the students' difficulties so that they can provide an appropriate combination of scaffolding to support their students in finding the solutions.
Decision Difficulty and Recall of Prose.
ERIC Educational Resources Information Center
Benton, Stephen L.; And Others
1983-01-01
Seven experiments were performed to address three issues: prose decisions of different levels of difficulty, directed attention effect, and the effects of decisions on memorability of prose among relatively good and relatively poor readers. (Author/PN)
McDonough, Ian M; Wong, Jessica T; Gallo, David A
2013-05-01
Current theories of cognitive aging emphasize that the prefrontal cortex might not only be a major source of dysfunction but also a source of compensation. We evaluated neural activity associated with retrieval monitoring--or the selection and evaluation of recollected information during memory retrieval--for evidence of dysfunction or compensation. Younger and older adults studied pictures and words and were subsequently given criterial recollection tests during event-related functional magnetic resonance imaging. Although memory accuracy was greater on the picture test than the word test in both groups, activity in right dorsolateral prefrontal cortex (DLPFC) was associated with greater retrieval monitoring demands (word test > picture test) only in younger adults. Similarly, DLPFC activity was consistently associated with greater item difficulty (studied > nonstudied) only in younger adults. Older adults instead exhibited high levels of DLPFC activity for all of these conditions, and activity was greater than younger adults even when test performance was naturally matched across the groups (picture test). Correlations also differed between DLPFC activity and test performance across the groups. Collectively, these findings are more consistent with accounts of DLPFC dysfunction than compensation, suggesting that aging disrupts the otherwise beneficial coupling between DLPFC recruitment and retrieval monitoring demands.
Reading acceleration training changes brain circuitry in children with reading difficulties
Horowitz-Kraus, Tzipi; Vannest, Jennifer J; Kadis, Darren; Cicchino, Nicole; Wang, Yingying Y; Holland, Scott K
2014-01-01
Introduction Dyslexia is characterized by slow, inaccurate reading. Previous studies have shown that the Reading Acceleration Program (RAP) improves reading speed and accuracy in children and adults with dyslexia and in typical readers across different orthographies. However, the effect of the RAP on the neural circuitry of reading has not been established. In the current study, we examined the effect of the RAP training on regions of interest in the neural circuitry for reading using a lexical decision task during fMRI in children with reading difficulties and typical readers. Methods Children (8–12 years old) with reading difficulties and typical readers were studied before and after 4 weeks of training with the RAP in both groups. Results In addition to improvements in oral and silent contextual reading speed, training-related gains were associated with increased activation of the left hemisphere in both children with reading difficulties and typical readers. However, only children with reading difficulties showed improvements in reading comprehension, which were associated with significant increases in right frontal lobe activation. Conclusions Our results demonstrate differential effects of the RAP on neural circuits supporting reading in both children with reading difficulties and typical readers and suggest that the intervention may stimulate use of typical neural circuits for reading and engage compensatory pathways to support reading in the developing brain of children with reading difficulties. PMID:25365797
ERIC Educational Resources Information Center
Kent, Shawn C.; Wanzek, Jeanne; Al Otaiba, Stephanie
2012-01-01
The purpose of this study was to examine the amount of time spent actively engaged in reading sounds, words, and connected text for students at-risk for reading difficulties in the first formal grade of reading instruction, kindergarten. Observational data of 109 kindergarten students at high-risk for later reading difficulties were collected…
Sleep problems of adolescents: A detailed survey.
Muluk, Nuray Bayar; Bulbul, Selda Fatma; Turğut, Mahmut; Ağirtaş, Gülşah
2015-06-01
We investigated the sleep problems and sleep habits of adolescents at three public primary schools and two high schools. Our study included 428 Turkish school children (244 girls and 184 boys). We used a questionnaire to determine the time they went to sleep at night; waking time in the morning; incidence of nightmares, snoring, daytime sleepiness, and intrafamilial physical trauma; concentration difficulty in class; and school success. The students were divided into age-related groups (group 1 = 11 to 13 years of age; group 2 = 14 to 15 years; group 3 = 16 to 18 years). The time they went to sleep was mostly between 10 and 11 p.m. in groups 1 and 2, and 11 to 12 p.m. in group 3. Difficulty in falling asleep was reported by 16.8 to 19.6% of the students in the three groups. Difficulty in waking up in the morning was reported by 12.7% of group 1, 16.0% of group 2, and 16.8% of group 3. Snoring was present in 12.1% of females and 22.0% of males. The occurrence of one nightmare in the preceding 3 months was reported by 11.3% of the students; 17.9% of the students reported having nightmares several times. Daytime sleepiness was present in 65.1%, and concentration difficulty was present in 56.8% of the students. We conclude that difficulty in falling asleep, snoring, and daytime sleepiness may be seen in adolescents who are in both primary and high schools. Watching inappropriate programs and movies on television and intrafamilial physical trauma may cause nightmares and sleeping problems in these adolescents. Students and families should be educated about the importance of sleep in academic performance. Countries' public health policies should address sleep problems and related educational activities.
ERIC Educational Resources Information Center
López, José María; Moreno-Rodríguez, Ricardo; Alcover, Carlos-María; Garrote, Inmaculada; Sánchez, Sergio
2017-01-01
Individuals with Autistic Spectrum Disorder (ASD) present learning difficulties and limited performance of social skills, besides lower motor skills performance in comparison with their peers. Owing to these difficulties, most of children with ASD are at risk of social exclusion or a poor inclusion due to their behavior, mainly playing with other…
Arokiaraj, Mark Christopher
2018-02-01
Difficulty in engaging with guide catheters is not uncommon in acute emergencies. We aimed to evaluate the use of Cordis ® INFINITI diagnostic catheters to perform angioplasty in patients in whom the coronaries cannot be engaged using standard guide catheters. In 34 cases of acute coronary syndrome, when difficulty in engagement with two standard guide catheters was encountered with reasonable manipulations, angioplasty was performed using diagnostic catheters. In total, 40 stents were placed by this technique. Pushability and trackability, distal tip flexion and three-point bending tests were performed to evaluate the performance of the guide and diagnostic catheters. Angioplasty was performed easily in a setting where it would have been very difficult to perform. Coronary dissection occurred in one patient, treated by a stent. The stent and dilatation balloons were easily passed through the diagnostic catheters. Pressure tracings were clearly preserved with certain stent delivery systems, and at angioplasty, although there was slightly reduced opacification of the respective artery, the coronary anatomy was sufficiently visualized to perform angioplasty. No periprocedural target lesion complications were seen in any cases. Pushability and trackability tests showed good force transmission along a tortuous path with diagnostic catheters, and balanced force-displacement curves from three-point bending tests and distal tip softness tests. Angioplasty with stenting can be performed safely through 6F Cordis ® infiniti diagnostic catheters when difficulty in engaging guide catheters is encountered. Copyright © 2018 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.
Kwon, Soo Jin; Kim, Yoonjung; Kwak, Yeunhee
2018-01-01
Attention-deficit hyperactivity disorder (ADHD) persists into adolescence and adulthood; however, few studies have analyzed the experiences of university students with ADHD. This study explored the difficulties experienced by university students with ADHD symptoms. Between December 2015 and February 2016, face-to-face interviews were conducted with 12 university students with self-reported ADHD symptoms. Data were analyzed using thematic analysis. Difficulties in university life were classified into four main themes (lack of daily routine, unsatisfactory academic performance and achievement, reduced interpersonal skills, and continuing worries) and analyzed. University students with ADHD symptoms had difficulties coping with repeated cycles of negative thoughts and worries, irregular lifestyles due to poor time management, dissatisfaction with academic performance and interpersonal relationships, self-dissatisfaction, and decreased self-esteem. To improve their university experience, students with ADHD should receive education about ways to stop worrying, to express emotions healthily, and to manage time efficiently.
Kuh, Diana; Bassey, E Joan; Butterworth, Suzanne; Hardy, Rebecca; Wadsworth, Michael E J
2005-02-01
Understanding the health, behavioral, and social factors that influence physical performance in midlife may provide clues to the origins of frailty in old age and the future health of elderly populations. The authors evaluated muscle strength, postural control, and chair rise performance in a large representative prospective cohort of 53-year-old British men and women in relation to functional limitations, body size, health and activity, and socioeconomic conditions. Nurses interviewed 2984 men and women in their own homes in England, Scotland, and Wales and conducted physical examinations in 2956 of them. Objective measures were height, weight, and three physical performance tests: handgrip strength, one-legged standing balance time, and time to complete 10 chair rises. Functional limitations (difficulties walking, stair climbing, gripping, and falls), health status, physical activity, and social class were obtained using a structured questionnaire. Those with the worst scores on the physical performance tests had higher rates of functional limitations for both upper and lower limbs. Women had much weaker handgrip strength, somewhat poorer balance time, and only slightly poorer chair rise time compared with men. In women, health problems and low levels of physical activity contributed to poor physical performance on all three measures. In men, physical activity was the predominant influence. Heavier weight and poorer socioeconomic conditions contributed to poorer balance and chair rise times. In this representative middle-aged group, physical performance levels varied widely, and women were seriously disadvantaged compared with men. In general, physical performance was worse for men and women living in poorer socioeconomic conditions with greater body weight, poorer health status, and inactive lifestyles. These findings support recommendations for controlling excess body weight, effective health interventions, and the maintenance of active lifestyles during aging.
Nilsson, Ingeborg; Nyqvist, Fredrica; Gustafson, Yngve; Nygård, Mikael
2015-01-01
Objectives. This study aims to investigate the impact of medical conditions, mobility difficulties, and activity limitations on older people's engagement in leisure activities. Methods. The analyses are based on a cross regional survey carried out in 2010 in the Bothnia region (Northern Sweden and Western Finland). A posted questionnaire, which included questions on different aspects of leisure engagement, medical history, and health, was sent out to older persons in the region. The final sample consisted of 5435 persons aged 65, 70, 75, and 80 years. The data was analyzed by using ordinary least squares (OLS) multivariate regression. Results. The most important predictor of leisure engagement abstention among older people is the prevalence of activity limitations, whereas mobility difficulties and medical conditions play less important roles. The strong negative association between activity limitations and leisure engagement remains significant even after we control for individual, sociodemographic characteristics, and country. Discussion. This study provides a window into leisure engagement in later life and factors influencing the magnitude of engagement in leisure activities. PMID:26346706
Tavares, Inês M; Laan, Ellen T M; Nobre, Pedro J
2017-06-01
Cognitive-affective factors contribute to female sexual dysfunctions, defined as clinically significant difficulties in the ability to respond sexually or to experience sexual pleasure. Automatic thoughts and affect presented during sexual activity are acknowledged as maintenance factors for these difficulties. However, there is a lack of studies on the influence of these cognitive-affective dimensions regarding female orgasm. To assess the role of automatic thoughts and affect during sexual activity in predicting female orgasm occurrence and to investigate the mediator role of these variables in the relation between sexual activity and orgasm occurrence. Nine hundred twenty-six sexually active heterosexual premenopausal women reported on frequency of sexual activities and frequency of orgasm occurrence, cognitive factors, and social desirability. Participants completed the Sexual Modes Questionnaire-Automatic Thoughts Subscale, the Positive and Negative Affect Schedule, and the Socially Desirable Response Set. Multiple linear regressions and mediation analyses were performed, controlling for the effect of covariates such as social desirability, sociodemographic and medical characteristics, and relationship factors. The main outcome measurement was orgasm frequency as predicted and mediated by automatic thoughts and affect experienced during sexual activities. The presence of failure thoughts and lack of erotic thoughts during sexual activity significantly and negatively predicted female orgasm, whereas positive affect experienced during sexual activity significantly and positively predicted female orgasm. Moreover, negative automatic thoughts and positive affect during sexual activity were found to mediate the relation between sexual activity and female orgasm occurrence. These data suggest that the cognitive aspects of sexual involvement are critical to enhancing female orgasm experience and can aid the development of strategies that contemplate the central role of automatic thoughts and of positive emotions experienced during sexual activity. Data were not collected face to face, which constitutes a strength of this study, because it is known that social desirability is lower in self-administered online questionnaires compared with traditional paper-and-pencil questionnaires, particularly for more sensitive sexual issues. The fact that the sample was composed of heterosexual, premenopausal, and relatively young women demands some caution regarding generalization of the present results. The findings support the contribution of cognitive and affective factors to female orgasmic functioning. It is recommended that future research confirm these findings with other samples, particularly clinical samples of women with orgasmic difficulties. Tavares IM, Laan ETM, Nobre PJ. Cognitive-Affective Dimensions of Female Orgasm: The Role of Automatic Thoughts and Affect During Sexual Activity. J Sex Med 2017;14:818-828. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Kubota, Kazumi; Shimazu, Akihito; Kawakami, Norito; Takahashi, Masaya; Nakata, Akinori; Schaufeli, Wilmar B
2011-01-01
The aim of the present study is to demonstrate the distinctiveness of work engagement and workaholism by examining their relationships with sleep quality and job performance. A total of 447 nurses from 3 hospitals in Japan were surveyed using a self-administrated questionnaire including Utrecht Work Engagement Scale (UWES), the Dutch Workaholism Scale (DUWAS), questions on sleep quality (7 items) regarding (1) difficulty initiating sleep, (2) difficulty maintaining sleep, (3) early morning awakening, (4) dozing off or napping in daytime, (5) excessive daytime sleepiness at work, (6) difficulty awakening in the morning, and (7) tiredness awakening in the morning, and the World Health Organization Health Work Performance Questionnaire. The Structural Equation Modeling showed that, work engagement was positively related to sleep quality and job performance whereas workaholism negatively to sleep quality and job performance. The findings suggest that work engagement and workaholism are conceptually distinctive and that the former is positively and the latter is negatively related to well-being (i.e., good sleep quality and job performance).
Boivin-Desrochers, Camille; Alderson, Marie
2014-10-01
The nursing profession is faced with an issue of growing concern, that of the mental health of its practitioners. The many difficulties that nurses experience in the workplace may prove to be detrimental to the maintenance of an optimal mental state. With respect to these difficulties, several strategies can be implemented and used by nurses and managers. The present literature review aims to identify the difficulties and suffering experienced by nurses and the strategies employed to ensure the preservation of mental health, as well as maintaining the calling of the profession and job performance. It also aims to provide nurses and managers of the health care system with ideas to promote optimal mental health for nurses. In this context, « psychodynamique du travail » was chosen as the framework to structure the analysis of the literature dealing with elements surrounding the suffering and difficulties experienced by nurses. The use of this theoretical framework deepens and supports the relationship between the suffering experienced at work and the mental health of nurses.
Vuontela, Virve; Steenari, Maija-Riikka; Aronen, Eeva T; Korvenoja, Antti; Aronen, Hannu J; Carlson, Synnöve
2009-02-01
Using functional magnetic resonance imaging (fMRI) and n-back tasks we investigated whether, in 11-13-year-old children, spatial (location) and nonspatial (color) information is differentially processed during visual attention (0-back) and working memory (WM) (2-back) tasks and whether such cognitive task performance, compared to a resting state, results in regional deactivation. The location 0-back task, compared to the color 0-back task, activated segregated areas in the frontal, parietal and occipital cortices whereas no differentially activated voxels were obtained when location and color 2-back tasks were directly contrasted. Several midline cortical areas were less active during 0- and 2-back task performance than resting state. The task-induced deactivation increased with task difficulty as demonstrated by larger deactivation during 2-back than 0-back tasks. The results suggest that, in 11-13-year-old children, the visual attentional network is differently recruited by spatial and nonspatial information processing, but the functional organization of cortical activation in WM in this age group is not based on the type of information processed. Furthermore, 11-13-year-old children exhibited a similar pattern of cortical deactivation that has been reported in adults during cognitive task performance compared to a resting state.
Piwowarczyk, Tatiana Carvalho; Oliveira, Gisele; Lourenço, Luciana; Behlau, Mara
2012-03-01
To analyze the phonatory and laryngopharyngeal symptoms reported by call center operators; and quantify the impact of these symptoms on quality of life, and the association between these issues and professional performance, number of monthly calls, and number of missed workdays. Call center operators (n=157) from a billing call center completed the Vocal Signs and Symptoms Questionnaire and the Brazilian version of the Voice Activity and Participation Profile (VAPP). The company provided data regarding professional performance, average number of monthly calls, and number of missed workdays for each employee. The mean number of current symptoms (6.8) was greater in the operators than data for the general population (1.7). On average, 4.2 symptoms were attributed to occupational factors. The average number of symptoms did not correlate with professional performance (P=0.571). However, fewer symptoms correlated with decreased missed workdays and higher mean monthly call figures. The VAPP scores were relatively low, suggesting little impact of voice difficulties on call center operator's quality of life. However, subjects with elevated VAPP scores also had poorer professional performance. The presence of vocal symptoms does not necessarily relate to decreased professional performance. However, an association between higher vocal activity limitation and participation scores and poorer professional performance was observed. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.
Brunette, Amanda M; Holm, Kristen E; Wamboldt, Frederick S; Kozora, Elizabeth; Moser, David J; Make, Barry J; Crapo, James D; Meschede, Kimberly; Weinberger, Howard D; Moreau, Kerrie L; Bowler, Russell P; Hoth, Karin F
2018-05-01
This study examined the association of perceived cognitive difficulties with objective cognitive performance in former smokers. We hypothesized that greater perceived cognitive difficulties would be associated with poorer performance on objective executive and memory tasks. Participants were 95 former smokers recruited from the COPDGene study. They completed questionnaires (including the Cognitive Difficulties Scale [CDS] and the Hospital Anxiety and Depression Scale [HADS]), neuropsychological assessment, and pulmonary function testing. Pearson correlations and t-tests were conducted to examine the bivariate association of the CDS (total score and subscales for attention/concentration, praxis, delayed recall, orientation for persons, temporal orientation, and prospective memory) with each domain of objective cognitive functioning (memory recall, executive functioning/processing speed, visuospatial processing, and language). Simultaneous multiple linear regression was used to further examine all statistically significant bivariate associations. The following covariates were included in all regression models: age, sex, pack-years, premorbid functioning (WRAT-IV Reading), HADS total score, and chronic obstructive pulmonary disease (COPD) status (yes/no based on GOLD criteria). In regression models, greater perceived cognitive difficulties overall (using CDS total score) were associated with poorer performance on executive functioning/processing speed tasks (b = -0.07, SE = 0.03, p = .037). Greater perceived cognitive difficulties on the CDS praxis subscale were associated with poorer performance on executive functioning/processing speed tasks (b = -3.65, SE = 1.25, p = .005), memory recall tasks (b = -4.60, SE = 1.75, p = .010), and language tasks (b = -3.89, SE = 1.39, p = .006). Clinicians should be aware that cognitive complaints may be indicative of problems with the executive functioning/processing speed and memory of former smokers with and without COPD.
Wang, Shinmin; Gathercole, Susan E
2013-05-01
The current study investigated the cause of the reported problems in working memory in children with reading difficulties. Verbal and visuospatial simple and complex span tasks, and digit span and reaction times tasks performed singly and in combination, were administered to 46 children with single word reading difficulties and 45 typically developing children matched for age and nonverbal ability. Children with reading difficulties had pervasive deficits in the simple and complex span tasks and had poorer abilities to coordinate two cognitive demanding tasks. These findings indicate that working memory problems in children with reading difficulties may reflect a core deficit in the central executive. Copyright © 2012 Elsevier Inc. All rights reserved.
Therapeutic Ultrasound Research And Development From An Industrial And Commercial Perspective
NASA Astrophysics Data System (ADS)
Seip, Ralf
2009-04-01
The objective of this paper is to share the challenges and opportunities as viewed from an industrial and commercial perspective that one encounters when performing therapeutic ultrasound research, development, manufacturing, and sales activities. Research in therapeutic ultrasound has become an active field in the last decade, spurred by technological advances in the areas of transducer materials, control electronics, treatment monitoring techniques, an ever increasing number of clinical applications, and private and governmental funding opportunities. The development of devices and methods utilizing therapeutic ultrasound to cure or manage disease is being pursued by startup companies and large established companies alike, driven by the promise of profiting at many levels from this new and disruptive technology. Widespread penetration within the clinical community remains elusive, with current approaches focusing on very specific applications and niche markets. Challenges include difficulties in securing capital to develop the technology and undertake costly clinical trials, a regulatory landscape that varies from country to country, resistance from established practitioners, and difficulties in assembling a team with the right mix of technological savvy and business expertise. Success is possible and increasing, however, as evidenced by several companies, initiatives, and products with measurable benefits to the patient, clinician, and companies alike.
Ganapathy, Vaidyanathan; Graham, Glenn D; DiBonaventura, Marco D; Gillard, Patrick J; Goren, Amir; Zorowitz, Richard D
2015-01-01
Objective Many stroke survivors experience poststroke spasticity and the related inability to perform basic activities, which necessitates patient management and treatment, and exerts a considerable burden on the informal caregiver. The current study aims to estimate burden, productivity loss, and indirect costs for caregivers of stroke survivors with spasticity. Methods Internet survey data were collected from 153 caregivers of stroke survivors with spasticity including caregiving time and difficulty (Oberst Caregiver Burden Scale), Work Productivity and Activity Impairment measures, and caregiver and patient characteristics. Fractional logit models examined predictors of work-related restriction, and work losses were monetized (2012 median US wages). Results Mean Oberst Caregiver Burden Scale time and difficulty scores were 46.1 and 32.4, respectively. Employed caregivers (n=71) had overall work restriction (32%), absenteeism (9%), and presenteeism (27%). Caregiver characteristics, lack of nursing home coverage, and stroke survivors’ disability predicted all work restriction outcomes. The mean total lost-productivity cost per employed caregiver was US$835 per month (>$10,000 per year; 72% attributable to presenteeism). Conclusion These findings demonstrate the substantial burden of caring for stroke survivors with spasticity illustrating the societal and economic impact of stroke that extends beyond the stroke survivor. PMID:26609225
Control of Auditory Attention in Children With Specific Language Impairment.
Victorino, Kristen R; Schwartz, Richard G
2015-08-01
Children with specific language impairment (SLI) appear to demonstrate deficits in attention and its control. Selective attention involves the cognitive control of attention directed toward a relevant stimulus and simultaneous inhibition of attention toward irrelevant stimuli. The current study examined attention control during a cross-modal word recognition task. Twenty participants with SLI (ages 9-12 years) and 20 age-matched peers with typical language development (TLD) listened to words through headphones and were instructed to attend to the words in 1 ear while ignoring the words in the other ear. They were simultaneously presented with pictures and asked to make a lexical decision about whether the pictures and auditory words were the same or different. Accuracy and reaction time were measured in 5 conditions, in which the stimulus in the unattended channel was manipulated. The groups performed with similar accuracy. Compared with their peers with TLD, children with SLI had slower reaction times overall and different within-group patterns of performance by condition. Children with TLD showed efficient inhibitory control in conditions that required active suppression of competing stimuli. Participants with SLI had difficulty exerting control over their auditory attention in all conditions, with particular difficulty inhibiting distractors of all types.
Perceptual and memorial contributions to developmental prosopagnosia.
Ulrich, Philip I N; Wilkinson, David T; Ferguson, Heather J; Smith, Laura J; Bindemann, Markus; Johnston, Robert A; Schmalzl, Laura
2017-02-01
Developmental prosopagnosia (DP) is commonly associated with the failure to properly perceive individuating facial properties, notably those conveying configural or holistic content. While this may indicate that the primary impairment is perceptual, it is conceivable that some cases of DP are instead caused by a memory impairment, with any perceptual complaint merely allied rather than causal. To investigate this possibility, we administered a battery of face perception tasks to 11 individuals who reported that their face recognition difficulties disrupt daily activity and who also performed poorly on two formal tests of face recognition. Group statistics identified, relative to age- and gender-matched controls, difficulties in apprehending global-local relations and the holistic properties of faces, and in matching across viewpoints, but these were mild in nature and were not consistently evident at the level of individual participants. Six of the 11 individuals failed to show any evidence of perceptual impairment. In the remaining five individuals, no single perceptual deficit, or combination of deficits, was necessary or sufficient for poor recognition performance. These data suggest that some cases of DP are better explained by a memorial rather than perceptual deficit, and highlight the relevance of the apperceptive/associative distinction more commonly applied to the allied syndrome of acquired prosopagnosia.
Cardoso-Leite, Pedro; Waszak, Florian
2014-07-01
A briefly flashed target stimulus can become "invisible" when immediately followed by a mask-a phenomenon known as backward masking, which constitutes a major tool in the cognitive sciences. One form of backward masking is termed metacontrast masking. It is generally assumed that in metacontrast masking, the mask suppresses activity on which the conscious perception of the target relies. This assumption biases conclusions when masking is used as a tool-for example, to study the independence between perceptual detection and motor reaction. This is because other models can account for reduced perceptual performance without requiring suppression mechanisms. In this study, we used signal detection theory to test the suppression model against an alternative view of metacontrast masking, referred to as the summation model. This model claims that target- and mask-related activations fuse and that the difficulty in detecting the target results from the difficulty to discriminate this fused response from the response produced by the mask alone. Our data support this alternative view. This study is not a thorough investigation of metacontrast masking. Instead, we wanted to point out that when a different model is used to account for the reduced perceptual performance in metacontrast masking, there is no need to postulate a dissociation between perceptual and motor responses to account for the data. Metacontrast masking, as implemented in the Fehrer-Raab situation, therefore is not a valid method to assess perceptual-motor dissociations.
NASA Astrophysics Data System (ADS)
Quebedeaux, James Edward
The focus of this study was to identify major conceptual difficulties that selected public high school physical science students encounter in understanding a standard electromagnetic spectrum diagram. A research-driven, modified version of that standard diagram was used in this study to determine the value added to student understanding of electromagnetic waves. A content analysis was performed on electromagnetic spectrum diagrams found in US textbooks from the 1950s through the present. A class of public high school physical science students participated in a study consisting of four activities conducted during a three-week unit. Students were given a pre- and post-achievement test and a pre- and post-survey on the regions of the electromagnetic spectrum. At the conclusion of each activity, selected students were interviewed and each co-constructed a concept map with the researcher. The Electromagnetic Spectrum Literacy Rubric (ESLR) was designed and used to assess students' conceptual understanding periodically as they proceeded through the unit study. A mixed methods analysis was performed, employing both qualitative and quantitative data. A paired t-test determined that there was a statistically significant difference (p = 0.014) between the pre- and post-achievement test scores for the class of students participating in the unit study. Effect sizes also determined that students have difficulties with mathematical calculations and wave properties. These topics present conceptual challenges which must be overcome to understand and use an electromagnetic spectrum diagram effectively.
How do the outcomes of the DEKA Arm compare to conventional prostheses?
Resnik, Linda J; Borgia, Matthew L; Acluche, Frantzy; Cancio, Jill M; Latlief, Gail; Sasson, Nicole
2018-01-01
Objectives were to 1) compare self-reported function, dexterity, activity performance, quality of life and community integration of the DEKA Arm to conventional prostheses; and 2) examine differences in outcomes by conventional prosthesis type, terminal device type and by DEKA Arm configuration level. This was a two-part study; Part A consisted of in-laboratory training. Part B consisted of home use. Study participants were 23 prosthesis users (mean age = 45 ± 16; 87% male) who completed Part A, and 15 (mean age = 45 ± 18; 87% male) who completed Parts A and B. Outcomes including self-report and performance measures, were collected at Baseline using participants' personal prostheses and at the End of Parts A and B. Scores were compared using paired t-tests. Wilcoxon signed-rank tests were used to compare outcomes for the full sample, and for the sample stratified by device and terminal device type. Analysis of outcomes by configuration level was performed graphically. At the End of Part A activity performance using the DEKA Arm and conventional prosthesis was equivalent, but slower with the DEKA Arm. After Part B, performance using the DEKA Arm surpassed conventional prosthesis scores, and speed of activity completion was equivalent. Participants reported using the DEKA Arm to perform more activities, had less perceived disability, and less difficulty in activities at the End of A and B as compared to Baseline. No differences were observed in dexterity, prosthetic skill, spontaneity, pain, community integration or quality of life. Comparisons stratified by device type revealed similar patterns. Graphic comparisons revealed variations by configuration level. Participants using the DEKA Arm had less perceived disability and more engagement of the prosthesis in everyday tasks, although activity performance was slower. After home use experience, activity performance was improved and activity speed equivalent to using conventional prostheses.
Difficulties in initial algebra learning in Indonesia
NASA Astrophysics Data System (ADS)
Jupri, Al; Drijvers, Paul; van den Heuvel-Panhuizen, Marja
2014-12-01
Within mathematics curricula, algebra has been widely recognized as one of the most difficult topics, which leads to learning difficulties worldwide. In Indonesia, algebra performance is an important issue. In the Trends in International Mathematics and Science Study (TIMSS) 2007, Indonesian students' achievement in the algebra domain was significantly below the average student performance in other Southeast Asian countries such as Thailand, Malaysia, and Singapore. This fact gave rise to this study which aims to investigate Indonesian students' difficulties in algebra. In order to do so, a literature study was carried out on students' difficulties in initial algebra. Next, an individual written test on algebra tasks was administered, followed by interviews. A sample of 51 grade VII Indonesian students worked the written test, and 37 of them were interviewed afterwards. Data analysis revealed that mathematization, i.e., the ability to translate back and forth between the world of the problem situation and the world of mathematics and to reorganize the mathematical system itself, constituted the most frequently observed difficulty in both the written test and the interview data. Other observed difficulties concerned understanding algebraic expressions, applying arithmetic operations in numerical and algebraic expressions, understanding the different meanings of the equal sign, and understanding variables. The consequences of these findings on both task design and further research in algebra education are discussed.
ADOLESCENT WORK INTENSITY, SCHOOL PERFORMANCE, AND ACADEMIC ENGAGEMENT.
Staff, Jeremy; Schulenberg, John E; Bachman, Jerald G
2010-07-01
Teenagers working over 20 hours per week perform worse in school than youth who work less. There are two competing explanations for this association: (1) that paid work takes time and effort away from activities that promote achievement, such as completing homework, preparing for examinations, getting help from parents and teachers, and participating in extracurricular activities; and (2) that the relationship between paid work and school performance is spurious, reflecting preexisting differences between students in academic ability, motivation, and school commitment. Using longitudinal data from the ongoing national Monitoring the Future project, this research examines the impact of teenage employment on school performance and academic engagement during the 8th, 10th, and 12th grades. We address issues of spuriousness by using a two-level hierarchical model to estimate the relationships of within-individual changes in paid work to changes in school performance and other school-related measures. Unlike prior research, we also compare youth school performance and academic orientation when they are actually working in high-intensity jobs to when they are jobless and wish to work intensively. Results indicate that the mere wish for intensive work corresponds with academic difficulties in a manner similar to actual intensive work.
ADOLESCENT WORK INTENSITY, SCHOOL PERFORMANCE, AND ACADEMIC ENGAGEMENT*
Staff, Jeremy; Schulenberg, John E.; Bachman, Jerald G.
2010-01-01
Teenagers working over 20 hours per week perform worse in school than youth who work less. There are two competing explanations for this association: (1) that paid work takes time and effort away from activities that promote achievement, such as completing homework, preparing for examinations, getting help from parents and teachers, and participating in extracurricular activities; and (2) that the relationship between paid work and school performance is spurious, reflecting preexisting differences between students in academic ability, motivation, and school commitment. Using longitudinal data from the ongoing national Monitoring the Future project, this research examines the impact of teenage employment on school performance and academic engagement during the 8th, 10th, and 12th grades. We address issues of spuriousness by using a two-level hierarchical model to estimate the relationships of within-individual changes in paid work to changes in school performance and other school-related measures. Unlike prior research, we also compare youth school performance and academic orientation when they are actually working in high-intensity jobs to when they are jobless and wish to work intensively. Results indicate that the mere wish for intensive work corresponds with academic difficulties in a manner similar to actual intensive work. PMID:20802795
2007-06-01
Video game -based environments are an increasingly popular medium for training Soldiers. This research investigated how various strategies for...modifying task difficulty over the progression of an instructional video game impact learner performance and motivation. Further, the influence of prior... video game experience on these learning outcomes was examined, as well as the role prior experience played in determining the optimal approach for
ERIC Educational Resources Information Center
Booth, Josephine N.; Boyle, James M. E.; Kelly, Steve W.
2010-01-01
Research studies have implicated executive functions in reading difficulties (RD). But while some studies have found children with RD to be impaired on tasks of executive function other studies report unimpaired performance. A meta-analysis was carried out to determine whether these discrepant findings can be accounted for by differences in the…
ERIC Educational Resources Information Center
Jitendra, Asha K.; Corroy, Kelly Cozine; Dupuis, Danielle N.
2013-01-01
The purposes of this study were (a) to evaluate differences in arithmetic word problem solving between high and low at-risk students for mathematics difficulties (MD) and (b) to assess the influence of attention, behavior, reading, and socio-economic status (SES) in predicting the word problem solving performance of third-grade students with MD.…
ERIC Educational Resources Information Center
Benson, Geetal
2013-01-01
This study examined the isolated effects of Cover, Copy and Compare (CCC) and the effects of CCC paired with performance feedback (CCC + PF) and rewards (CCC + RW) on the mathematical calculation skills of first grade students identified with math difficulty. Four research questions were addressed in this study. 1. Does Cover, Copy, and Compare…
When Listening Is Better Than Reading: Performance Gains on Cardiac Auscultation Test Questions.
Short, Kathleen; Bucak, S Deniz; Rosenthal, Francine; Raymond, Mark R
2018-05-01
In 2007, the United States Medical Licensing Examination embedded multimedia simulations of heart sounds into multiple-choice questions. This study investigated changes in item difficulty as determined by examinee performance over time. The data reflect outcomes obtained following initial use of multimedia items from 2007 through 2012, after which an interface change occurred. A total of 233,157 examinees responded to 1,306 cardiology test items over the six-year period; 138 items included multimedia simulations of heart sounds, while 1,168 text-based items without multimedia served as controls. The authors compared changes in difficulty of multimedia items over time with changes in difficulty of text-based cardiology items over time. Further, they compared changes in item difficulty for both groups of items between graduates of Liaison Committee on Medical Education (LCME)-accredited and non-LCME-accredited (i.e., international) medical schools. Examinee performance on cardiology test items with multimedia heart sounds improved by 12.4% over the six-year period, while performance on text-based cardiology items improved by approximately 1.4%. These results were similar for graduates of LCME-accredited and non-LCME-accredited medical schools. Examinees' ability to interpret auscultation findings in test items that include multimedia presentations increased from 2007 to 2012.
Navarro, Juan-José; Lara, Laura
2017-01-01
Dynamic Assessment (DA) has been shown to have more predictive value than conventional tests for academic performance. However, in relation to reading difficulties, further research is needed to determine the predictive validity of DA for specific aspects of the different processes involved in reading and the differential validity of DA for different subgroups of students with an academic disadvantage. This paper analyzes the implementation of a DA device that evaluates processes involved in reading (EDPL) among 60 students with reading comprehension difficulties between 9 and 16 years of age, of whom 20 have intellectual disabilities, 24 have reading-related learning disabilities, and 16 have socio-cultural disadvantages. We specifically analyze the predictive validity of the EDPL device over attitude toward reading, and the use of dialogue/participation strategies in reading activities in the classroom during the implementation stage. We also analyze if the EDPL device provides additional information to that obtained with a conventionally applied personal-social adjustment scale (APSL). Results showed that dynamic scores, obtained from the implementation of the EDPL device, significantly predict the studied variables. Moreover, dynamic scores showed a significant incremental validity in relation to predictions based on an APSL scale. In relation to differential validity, the results indicated the superior predictive validity for DA for students with intellectual disabilities and reading disabilities than for students with socio-cultural disadvantages. Furthermore, the role of metacognition and its relation to the processes of personal-social adjustment in explaining the results is discussed.
Navarro, Juan-José; Lara, Laura
2017-01-01
Dynamic Assessment (DA) has been shown to have more predictive value than conventional tests for academic performance. However, in relation to reading difficulties, further research is needed to determine the predictive validity of DA for specific aspects of the different processes involved in reading and the differential validity of DA for different subgroups of students with an academic disadvantage. This paper analyzes the implementation of a DA device that evaluates processes involved in reading (EDPL) among 60 students with reading comprehension difficulties between 9 and 16 years of age, of whom 20 have intellectual disabilities, 24 have reading-related learning disabilities, and 16 have socio-cultural disadvantages. We specifically analyze the predictive validity of the EDPL device over attitude toward reading, and the use of dialogue/participation strategies in reading activities in the classroom during the implementation stage. We also analyze if the EDPL device provides additional information to that obtained with a conventionally applied personal-social adjustment scale (APSL). Results showed that dynamic scores, obtained from the implementation of the EDPL device, significantly predict the studied variables. Moreover, dynamic scores showed a significant incremental validity in relation to predictions based on an APSL scale. In relation to differential validity, the results indicated the superior predictive validity for DA for students with intellectual disabilities and reading disabilities than for students with socio-cultural disadvantages. Furthermore, the role of metacognition and its relation to the processes of personal-social adjustment in explaining the results is discussed. PMID:28243215
Labadie, Robert F; Balachandran, Ramya; Noble, Jack H; Blachon, Grégoire S; Mitchell, Jason E; Reda, Fitsum A; Dawant, Benoit M; Fitzpatrick, J Michael
2015-01-01
OBJECTIVE Minimally-invasive image-guided approach to cochlear implantation (CI) involves drilling a narrow, linear tunnel to the cochlea. Reported herein is the first clinical implementation of this approach. STUDY DESIGN Prospective, cohort study. METHODS On preoperative CT, a safe linear trajectory through the facial recess targeting the scala tympani was planned. Intraoperatively, fiducial markers were bone-implanted, a second CT was acquired, and the trajectory was transferred from preoperative to intraoperative CT. A customized microstereotactic frame was rapidly designed and constructed to constrain a surgical drill along the desired trajectory. Following sterilization, the frame was employed to drill the tunnel to the middle ear. After lifting a tympanomeatal flap and performing a cochleostomy, the electrode array was threaded through the drilled tunnel and into the cochlea. RESULTS Eight of nine patients were successfully implanted using the proposed approach with six insertions completely within scala tympani. Traditional mastoidectomy was performed on one patient following difficulty threading the electrode array via the narrow tunnel. Other difficulties encountered included use of the back-up implant when an electrode was dislodged during threading via the tunnel, tip fold-over, and facial nerve paresis (House-Brackmann II/VII at 12 months) secondary to heat during drilling. Average time of intervention was 182±36 minutes. CONCLUSION Minimally-invasive, image-guided CI is clinically achievable. Further clinical study is necessary to address technological difficulties during drilling and insertion and to assess potential benefits including decreased time of intervention, standardization of surgical intervention, and decreased tissue dissection potentially leading to shorter recovery and earlier implant activation. PMID:24272427
Cortical processes associated with continuous balance control as revealed by EEG spectral power.
Hülsdünker, T; Mierau, A; Neeb, C; Kleinöder, H; Strüder, H K
2015-04-10
Balance is a crucial component in numerous every day activities such as locomotion. Previous research has reported distinct changes in cortical theta activity during transient balance instability. However, there remains little understanding of the neural mechanisms underlying continuous balance control. This study aimed to investigate cortical theta activity during varying difficulties of continuous balance tasks, as well as examining the relationship between theta activity and balance performance. 37 subjects completed nine balance tasks with different levels of surface stability and base of support. Throughout the balancing task, electroencephalogram (EEG) was recorded from 32 scalp locations. ICA-based artifact rejection was applied and spectral power was analyzed in the theta frequency band. Theta power increased in the frontal, central, and parietal regions of the cortex when balance tasks became more challenging. In addition, fronto-central and centro-parietal theta power correlated with balance performance. This study demonstrates the involvement of the cerebral cortex in maintaining upright posture during continuous balance tasks. Specifically, the results emphasize the important role of frontal and parietal theta oscillations in balance control. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Leisure activities and attitude of institutionalized elderly people: a basis for nursing practice.
de Castro, Vivian Carla; Carreira, Lígia
2015-01-01
to identify the leisure activities performed in Long-Stay Institutions for the Elderly (LSIEs), registered in the city of Maringá-PR, Brazil, and to analyze the attitude of the elderly people toward leisure promoted by the institutions. this was a descriptive and transversal study with a quantitative approach, carried out with 97 elderly people, through the establishment of the socio-demographic profile and the application of the Leisure Attitude Scale. The data was subjected to descriptive statistical analysis, association tests (chi-square or Fisher's) and Spearman's correlation. males, aged 80 or over, widowed, with one to eight years of study, who had a monthly income were predominant. Age group and income were significantly associated with the performance of leisure activities. The results reflected the positive attitude of the elderly people in relation to leisure activities, except in the behavioral component. the findings of this study indicate the need for further investigation into the difficulties linked to the attitude toward leisure in the behavioral component, considering aspects such as individual concepts of leisure and the health status of the elderly people.
Premenstrual Syndrome and Premenstrual Dysphoric Disorder in Japanese Collegiate Athletes.
Takeda, Takashi; Imoto, Yoko; Nagasawa, Hiroyo; Muroya, Miyuki; Shiina, Masami
2015-08-01
To determine the prevalence and impact of premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD) in Japanese collegiate athletes, with a focus on their disruption of athletic performance. Cross-sectional study. A university in Osaka, the largest city in western Japan. 232 female collegiate athletes. Premenstrual symptoms and social activities. The prevalence of each premenstrual symptom was high. The prevalence of moderate to severe PMS and PMDD was 8.6% and 2.9%, respectively, the same as in general high school students. The athletic performance of 44.3% of athletes was found to suffer in a game or in practice. "Elite athletes" (OR 8.63, 95% CI: 1.22-120.0), "Difficulty concentrating" (OR 3.15, 95% CI: 1.05-10.6), and "Fatigue or lack of energy" (OR 5.92, 95% CI: 1.32-34.5) increased the risk of poor athletic performance. This study showed that premenstrual symptoms affect not only the daily activities but also the athletic performance of collegiate athletes. Copyright © 2015 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.
Dennis, Andrea; Bosnell, Rose; Dawes, Helen; Howells, Ken; Cockburn, Janet; Kischka, Udo; Matthews, Paul; Johansen-Berg, Heidi
2011-04-01
Stroke patients often have difficulties in simultaneously performing a motor and cognitive task. Functional imaging studies have shown that movement of an affected hand after stroke is associated with increased activity in multiple cortical areas, particularly in the contralesional hemisphere. We hypothesized patients for whom executing simple movements demands greater selective attention will show greater brain activity during movement. Eight chronic stroke patients performed a behavioral interference test using a visuo-motor tracking with and without a simultaneous cognitive task. The magnitude of behavioral task decrement under cognitive motor interference (CMI) conditions was calculated for each subject. Functional MRI was used to assess brain activity in the same patients during performance of a visuo-motor tracking task alone; correlations between CMI score and movement-related brain activation were then explored. Movement-related activation in the dorsal precentral gyrus of the contralesional hemisphere correlated strongly and positively with CMI score (r(2) at peak voxel=0.92; P<0.05). Similar but weaker relationships were observed in the ventral precentral and middle frontal gyrus. There was no independent relationship between hand motor impairment and CMI. Results suggest that variations in the degree to which a cognitive task interferes with performance of a concurrent motor task explains a substantial proportion of the variations in movement-related brain activity in patients after stroke. The results emphasize the importance of considering cognitive context when interpreting brain activity patterns and provide a rationale for further evaluation of integrated cognitive and movement interventions for rehabilitation in stroke.
The influence of classroom peers on cognitive performance in children with behavioural problems.
Bevington, J; Wishart, J G
1999-03-01
Identifying factors linked to underachievement is fundamental to understanding the associated academic difficulties and crucial to the development of effective intervention strategies. Underachievement in a number of academic domains has been shown to be associated with behavioural problems in the classroom but the nature of the association and direction of any causal link has yet to be clarified. This study explored the association between poor academic achievement and behavioural problems by examining the direct effects of peer presence on classroom performance in children with identified behavioural difficulties. Specifically, it was hypothesised that independent performance on a cognitive task would decrease as number of classroom peers present increased. A total of 24 children attending two special schools for children with emotional and behavioural difficulties participated in the study. Age range was 9-14 years. A within-subjects design was used in which performance on a set of perceptual/conceptual matching tasks was assessed under three conditions: the child working alone, alongside one other peer, or within a group of six. Measures of non-verbal intelligence and academic attainment were collected, along with teacher ratings of the severity of each child's problem behaviour. Performance was found to be significantly influenced by peer presence, both in terms of number of correct responses and time taken to complete the matching tasks. Direction of effects on these two performance indicators differed according to number of peers present. Findings highlight the importance of contextual factors in determining classroom performance in children with behavioural difficulties. Given the current pressure to educate all children in mainstream classes, findings have implications for classroom management.
DiLauro, Michelle; Pereira, Amanda; Carr, Jennifer; Chiu, Mary; Wesson, Virginia
2015-02-20
Spousal caregivers of persons with dementia often have difficulty engaging persons with dementia in leisure activities. This qualitative descriptive study identifies how caregivers perceive their spouses' participation in leisure activities since dementia onset and the professional guidance caregivers require to increase persons with dementia participation in shared leisure activities. Nine spousal caregivers from a hospital-based caregiver intervention attended one of three focus groups. Using symbolic interactionism and selective optimization with compensation theory as guiding frameworks, thematic content analysis was performed. Three major themes were identified: Recognizing and acknowledging changes, Making sense of changes and conflicts, and Embracing changes and forging ahead. Findings can be used by healthcare providers to better understand caregivers' needs for engaging persons with dementia in shared leisure activities, and inform development of feedback protocols to enhance caregiver interventions. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Chen, Tao; Li, Hongmei; Zou, Denglang; Liu, Yongling; Chen, Chen; Zhou, Guoying; Li, Yulin
2016-08-01
Anthraquinone glycosides, such as chrysophanol 1-O-β-d-glucoside, chrysophanol 8-O-β-d-glucoside, and physion 8-O-β-d-glucoside, are the accepted important active components of Rheum tanguticum Maxim. ex Balf. due to their pharmacological properties: antifungal, antimicrobial, cytotoxic, and antioxidant activities. However, an effective method for the separation of the above-mentioned anthraquinone glycosides from this herb is not currently available. Especially, greater difficulty existed in the separation of the two isomers chrysophanol 1-O-β-d-glucoside and chrysophanol 8-O-β-d-glucoside. This study demonstrated an efficient strategy based on preparative high-performance liquid chromatography and high-speed countercurrent chromatography for the separation of the above-mentioned anthraquinone glycosides from Rheum tanguticum Maxim.ex Balf. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Biomimetic wall-shaped hierarchical microstructure for gecko-like attachment.
Kasem, Haytam; Tsipenyuk, Alexey; Varenberg, Michael
2015-04-21
Most biological hairy adhesive systems involved in locomotion rely on spatula-shaped terminal elements, whose operation has been actively studied during the last decade. However, though functional principles underlying their amazing performance are now well understood, due to technical difficulties in manufacturing the complex structure of hierarchical spatulate systems, a biomimetic surface structure featuring true shear-induced dynamic attachment still remains elusive. To try bridging this gap, a novel method of manufacturing gecko-like attachment surfaces is devised based on a laser-micromachining technology. This method overcomes the inherent disadvantages of photolithography techniques and opens wide perspectives for future production of gecko-like attachment systems. Advanced smart-performance surfaces featuring thin-film-based hierarchical shear-activated elements are fabricated and found capable of generating friction force of several tens of times the contact load, which makes a significant step forward towards a true gecko-like adhesive.
NASA Technical Reports Server (NTRS)
Berg, S. L.; Sheridan, T. B.
1984-01-01
Four highly experienced Air Force pilots each flew four simulated flight scenarios. Two scenarios required a great deal of aircraft maneuvering. The other two scenarios involved less maneuvering, but required remembering a number of items. All scenarios were designed to be equaly challenging. Pilot's Subjective Ratings for Activity-level, Complexity, Difficulty, Stress, and Workload were higher for the manuevering scenarios than the memory scenarios. At a moderate workload level, keeping the pilots active resulted in better aircraft control. When required to monitor and remember items, aircraft control tended to decrease. Pilots tended to weigh information about the spatial positioning and performance of their aircraft more heavily than other items.
Practical difficulties in the diagnosis of transient non-ketotic hyperglycinaemia.
Lang, T F; Parr, J R; Matthews, E E; Gray, R G F; Bonham, J R; Kay, J D S
2008-02-01
Making a diagnosis of transient non-ketotic hyperglycinaemia (tNKH) can be difficult. We report an infant who presented in the neonatal period with symptoms of NKH. Metabolic studies performed on day 2 of life showed raised cerebrospinal fluid (CSF) and plasma glycine, and a CSF:plasma glycine ratio consistent with NKH; however, a liver biopsy performed on day 5 revealed normal liver glycine cleavage system activity. Subsequently, the child's clinical condition improved in the absence of any therapeutic medication. Clinical assessment and developmental follow-up at 5 months, 1 year, and 2 years were age-appropriate. Guidance for the investigation and management of future suspected cases of tNKH is discussed.
Sustained attention assessment of narcoleptic patients: two case reports.
Moraes, Mirleny; Wilson, Barbara A; Rossini, Sueli; Osternack-Pinto, Kátia; Reimão, Rubens
2008-01-01
Narcolepsy is a sleep disorder characterized by uncontrollable REM sleep attacks which alter the patients wake state and can lead to difficulties in attention aspects, such as maintaining attention when performing activities or tasks. This study aimed to evaluate sustained attention performance of two narcoleptic patients on the d2 Test, Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI) and Hamilton Rating Scale for Depression (HAM-D). Results showed that the maintenance of attention was associated with a slowing of the target symbols processing function in visual scanning with accuracy in task performance. A high degree of excessive sleepiness was observed, along with mild and moderate degrees of depressive signs and symptoms. One subject also presented with a nocturnal sleep disorder which could represent an important factor affecting attentional and affective capacity.
Kelley, Brian P; Franzblau, Lauren E; Chung, Kevin C; Carlozzi, Noelle; Waljee, Jennifer F
2016-07-01
Congenital hand differences induce social, psychological, and functional challenges for children. However, little is known about how children perceive their outcomes after reconstructive or what concerns children have. A total of 33 children (aged 6 to 17 years) who were treated for congenital hand differences, and their parents, participated in qualitative, semistructured interviews regarding the child's hand function and appearance. Discussion focused on the influence of congenital hand differences on the child's daily activities, school, and participation in sports and music. The interviews were open format to allow for spontaneous emergence of relevant themes followed by guided questioning. The interviews were transcribed verbatim and analyzed using qualitative coding, iterative comparisons, and frequency analysis to reveal perceptions of children and parents. In this sample, 73 percent of children and parents reported difficulty with hand function. Children experienced difficulties with personal care (58 percent), school activities (30 percent), and household tasks (27 percent). Children were bothered by hand appearance (48 percent), pain (30 percent), and weakness (24 percent). Complex anomalies were associated with greater disability and limitation in sports and music. Children with congenital hand differences are concerned with the aesthetics of their hands and limitations in their ability to perform activities. Children were often discouraged by activities that their peers accomplished easily, but with increasing age demonstrated adaptive behaviors to accommodate in their "own way," suggesting the uniqueness of their limitations. Patients may benefit from early hand therapy guided toward areas of concern to enhance functional adaptation.
Altmann, Lori J. P.; Stegemöller, Elizabeth; Hazamy, Audrey A.; Wilson, Jonathan P.; Okun, Michael S.; McFarland, Nikolaus R.; Shukla, Aparna Wagle; Hass, Chris J.
2015-01-01
Background When performing two tasks at once, a dual task, performance on one or both tasks typically suffers. People with Parkinson’s disease (PD) usually experience larger dual task decrements on motor tasks than healthy older adults (HOA). Our objective was to investigate the decrements in cycling caused by performing cognitive tasks with a range of difficulty in people with PD and HOAs. Methods Twenty-eight participants with Parkinson’s disease and 20 healthy older adults completed a baseline cycling task with no secondary tasks and then completed dual task cycling while performing 12 tasks from six cognitive domains representing a wide range of difficulty. Results Cycling was faster during dual task conditions than at baseline, and was significantly faster for six tasks (all p<.02) across both groups. Cycling speed improved the most during the easiest cognitive tasks, and cognitive performance was largely unaffected. Cycling improvement was predicted by task difficulty (p<.001). People with Parkinson’s disease cycled slower (p<.03) and showed reduced dual task benefits (p<.01) than healthy older adults. Conclusions Unexpectedly, participants’ motor performance improved during cognitive dual tasks, which cannot be explained in current models of dual task performance. To account for these findings, we propose a model integrating dual task and acute exercise approaches which posits that cognitive arousal during dual tasks increases resources to facilitate motor and cognitive performance, which is subsequently modulated by motor and cognitive task difficulty. This model can explain both the improvement observed on dual tasks in the current study and more typical dual task findings in other studies. PMID:25970607
A grid for a precise analysis of daily activities.
Wojtasik, V; Olivier, C; Lekeu, F; Quittre, A; Adam, S; Salmon, E
2010-01-01
Assessment of daily living activities is essential in patients with Alzheimer's disease. Most current tools quantitatively assess overall ability but provide little qualitative information on individual difficulties. Only a few tools allow therapists to evaluate stereotyped activities and record different types of errors. We capitalised on the Kitchen Activity Assessment to design a widely applicable analysis grid that provides both qualitative and quantitative data on activity performance. A cooking activity was videotaped in 15 patients with dementia and assessed according to the different steps in the execution of the task. The evaluations obtained with our grid showed good correlations between raters, between versions of the grid and between sessions. Moreover, the degree of independence obtained with our analysis of the task correlated with the Kitchen Activity Assessment score and with a global score of cognitive functioning. We conclude that assessment of a daily living activity with this analysis grid is reproducible and relatively independent of the therapist, and thus provides quantitative and qualitative information useful for both evaluating and caring for demented patients.
Discovering Activities to Recognize and Track in a Smart Environment
Rashidi, Parisa; Cook, Diane J.; Holder, Lawrence B.; Schmitter-Edgecombe, Maureen
2011-01-01
The machine learning and pervasive sensing technologies found in smart homes offer unprecedented opportunities for providing health monitoring and assistance to individuals experiencing difficulties living independently at home. In order to monitor the functional health of smart home residents, we need to design technologies that recognize and track activities that people normally perform as part of their daily routines. Although approaches do exist for recognizing activities, the approaches are applied to activities that have been pre-selected and for which labeled training data is available. In contrast, we introduce an automated approach to activity tracking that identifies frequent activities that naturally occur in an individual’s routine. With this capability we can then track the occurrence of regular activities to monitor functional health and to detect changes in an individual’s patterns and lifestyle. In this paper we describe our activity mining and tracking approach and validate our algorithms on data collected in physical smart environments. PMID:21617742
The Synapse Project: Engagement in mentally challenging activities enhances neural efficiency.
McDonough, Ian M; Haber, Sara; Bischof, Gérard N; Park, Denise C
2015-01-01
Correlational and limited experimental evidence suggests that an engaged lifestyle is associated with the maintenance of cognitive vitality in old age. However, the mechanisms underlying these engagement effects are poorly understood. We hypothesized that mental effort underlies engagement effects and used fMRI to examine the impact of high-challenge activities (digital photography and quilting) compared with low-challenge activities (socializing or performing low-challenge cognitive tasks) on neural function at pretest, posttest, and one year after the engagement program. In the scanner, participants performed a semantic-classification task with two levels of difficulty to assess the modulation of brain activity in response to task demands. The High-Challenge group, but not the Low-Challenge group, showed increased modulation of brain activity in medial frontal, lateral temporal, and parietal cortex-regions associated with attention and semantic processing-some of which were maintained a year later. This increased modulation stemmed from decreases in brain activity during the easy condition for the High-Challenge group and was associated with time committed to the program, age, and cognition. Sustained engagement in cognitively demanding activities facilitated cognition by increasing neural efficiency. Mentally-challenging activities may be neuroprotective and an important element to maintaining a healthy brain into late adulthood.
The Synapse Project: Engagement in mentally challenging activities enhances neural efficiency
McDonough, Ian M.; Haber, Sara; Bischof, Gérard N.; Park, Denise C.
2015-01-01
Purpose: Correlational and limited experimental evidence suggests that an engaged lifestyle is associated with the maintenance of cognitive vitality in old age. However, the mechanisms underlying these engagement effects are poorly understood. We hypothesized that mental effort underlies engagement effects and used fMRI to examine the impact of high-challenge activities (digital photography and quilting) compared with low-challenge activities (socializing or performing low-challenge cognitive tasks) on neural function at pretest, posttest, and one year after the engagement program. Methods: In the scanner, participants performed a semantic-classification task with two levels of difficulty to assess the modulation of brain activity in response to task demands. Results: The High-Challenge group, but not the Low-Challenge group, showed increased modulation of brain activity in medial frontal, lateral temporal, and parietal cortex—regions associated with attention and semantic processing—some of which were maintained a year later. This increased modulation stemmed from decreases in brain activity during the easy condition for the High-Challenge group and was associated with time committed to the program, age, and cognition. Conclusions: Sustained engagement in cognitively demanding activities facilitated cognition by increasing neural efficiency. Mentally-challenging activities may be neuroprotective and an important element to maintaining a healthy brain into late adulthood. PMID:26484698
Küper, Kristina; Gajewski, Patrick D.; Frieg, Claudia; Falkenstein, Michael
2017-01-01
Executive functions are subject to a marked age-related decline, but have been shown to benefit from cognitive training interventions. As of yet, it is, however, still relatively unclear which neural mechanism can mediate training-related performance gains. In the present electrophysiological study, we examined the effects of multi-domain cognitive training on performance in an untrained cue-based task switch paradigm featuring Stroop color words: participants either had to indicate the word meaning of Stroop stimuli (word task) or perform the more difficult task of color naming (color task). One-hundred and three older adults (>65 years old) were randomly assigned to a training group receiving a 4-month multi-domain cognitive training, a passive no-contact control group or an active (social) control group receiving a 4-month relaxation training. For all groups, we recorded performance and EEG measures before and after the intervention. For the cognitive training group, but not for the two control groups, we observed an increase in response accuracy at posttest, irrespective of task and trial type. No training-related effects on reaction times were found. Cognitive training was also associated with an overall increase in N2 amplitude and a decrease of P2 latency on single trials. Training-related performance gains were thus likely mediated by an enhancement of response selection and improved access to relevant stimulus-response mappings. Additionally, cognitive training was associated with an amplitude decrease in the time window of the target-locked P3 at fronto-central electrodes. An increase in the switch positivity during advance task preparation emerged after both cognitive and relaxation training. Training-related behavioral and event-related potential (ERP) effects were not modulated by task difficulty. The data suggest that cognitive training increased slow negative potentials during target processing which enhanced the N2 and reduced a subsequent P3-like component on both switch and non-switch trials and irrespective of task difficulty. Our findings further corroborate the effectiveness of multi-domain cognitive training in older adults and indicate that ERPs can be instrumental in uncovering the neural processes underlying training-related performance gains. PMID:28446870
Simple mental addition in children with and without mild mental retardation.
Janssen, R; De Boeck, P; Viaene, M; Vallaeys, L
1999-11-01
The speeded performance on simple mental addition problems of 6- and 7-year-old children with and without mild mental retardation is modeled from a person perspective and an item perspective. On the person side, it was found that a single cognitive dimension spanned the performance differences between the two ability groups. However, a discontinuity, or "jump," was observed in the performance of the normal ability group on the easier items. On the item side, the addition problems were almost perfectly ordered in difficulty according to their problem size. Differences in difficulty were explained by factors related to the difficulty of executing nonretrieval strategies. All findings were interpreted within the framework of Siegler's (e.g., R. S. Siegler & C. Shipley, 1995) model of children's strategy choices in arithmetic. Models from item response theory were used to test the hypotheses. Copyright 1999 Academic Press.
Examining the response programming function of the Quiet Eye: Do tougher shots need a quieter eye?
Walters-Symons, Rosanna; Wilson, Mark; Klostermann, Andre; Vine, Samuel
2018-02-01
Support for the proposition that the Quiet Eye (QE) duration reflects a period of response programming (including task parameterisation) has come from research showing that an increase in task difficulty is associated with increases in QE duration. Here, we build on previous research by manipulating three elements of task difficulty that correspond with different parameters of golf-putting performance; force production, impact quality and target line. Longer QE durations were found for more complex iterations of the task and furthermore, more sensitive analyses of the QE duration suggest that the early QE proportion (prior to movement initiation) is closely related to force production and impact quality. However, these increases in QE do not seem functional in terms of supporting improved performance. Further research is needed to explore QE's relationship with performance under conditions of increased difficulty.
The effect of speed-accuracy strategy on response interference control in Parkinson's disease.
Wylie, S A; van den Wildenberg, W P M; Ridderinkhof, K R; Bashore, T R; Powell, V D; Manning, C A; Wooten, G F
2009-07-01
Studies that used conflict paradigms such as the Eriksen Flanker task show that many individuals with Parkinson's disease (PD) have pronounced difficulty resolving the conflict that arises from the simultaneous activation of mutually exclusive responses. This finding fits well with contemporary views that postulate a key role for the basal ganglia in action selection. The present experiment aims to specify the cognitive processes that underlie action selection deficits among PD patients in the context of variations in speed-accuracy strategy. PD patients (n=28) and healthy controls (n=17) performed an arrow version of the flanker task under task instructions that either emphasized speed or accuracy of responses. Reaction time (RT) and accuracy rates decreased with speed compared to accuracy instructions, although to a lesser extent for the PD group. Differences in flanker interference effects among PD and healthy controls depended on speed-accuracy strategy. Compared to the healthy controls, PD patients showed larger flanker interference effects under speed stress. RT distribution analyses suggested that PD patients have greater difficulty suppressing incorrect response activation when pressing for speed. These initial findings point to an important interaction between strategic and computational aspects of interference control in accounting for cognitive impairments of PD. The results are also compatible with recent brain imaging studies that demonstrate basal ganglia activity to co-vary with speed-accuracy adjustments.
Lucena, Thomas R; Lam, Patrick H; Millar, Neal L
2015-01-01
Background The present study aimed to determine how repair technique influenced structural and clinical outcomes at 5 years post-surgery. Methods Three cohorts of patients had repair of a symptomatic rotator cuff tear using (i) an open double-row mattress repair technique (n = 25); (ii) arthroscopic single-row simple suture knotted technique (n = 25); or (iii) arthroscopic single-row inverted mattress knotless technique (n = 36) by one surgeon. Standardized patient- and examiner-determined outcomes were obtained pre-operatively and postoperatively with a validated protocol, ultrasound were also performed at the same time. Results Retear occurred more often after open repair (48%) at 5 years than after arthroscopic knotted (33%) and arthroscopic knotless (26%) repair. Retear was associated with increasing age, pre-operative tear size and weaker pre-operative and 5 years postoperative cuff strength. Between 2 years and 5 years, the open repair group experienced an increase in the frequency of pain during activity, as well as in the difficulty experienced and the severity of pain during overhead activities (p < 0.05) and, at 5 years, also experienced more difficulty with overhead activities, compared to the arthroscopic knotless repair group. Conclusions At 5-year follow-up, arthroscopic rotator cuff repair techniques resulted in fewer retears and better outcomes compared to an open double-row technique. PMID:27582985
Orfei, Maria Donata; Varsi, Ambra Erika; Blundo, Carlo; Celia, Elisabetta; Casini, Anna Rosa; Caltagirone, Carlo; Spalletta, Gianfranco
2010-12-01
To evaluate severity of anosognosia and to identify its neuropsychological correlates in preclinical and clinical Alzheimer's Disease (AD). The Clinical Insight Rating Scale, the Anosognosia Questionnaire for Dementia (AQ-D), and the Mental Deterioration Battery were used to assess anosognosia and cognitive performances in mild AD (N = 38), amnesic mild cognitive impairment (a-MCI; N = 35), and multiple domain MCI (md-MCI; N = 38). Patients with mild AD were more anosognosic than both MCI groups, which, however, did not differ from one other. A categorical diagnosis of anosognosia was made in 42% of patients with mild AD, 3% of md-MCI, but in no subjects with a-MCI. Reduced verbal episodic memory raw score was associated with decreased awareness of cognitive difficulties (AQ-D total and intellectual functioning scores) only in MCI. In mild AD, anosognosia was linked only to increased age and reduced basic activities of daily living performances. The diagnosis of anosognosia is frequent in patients with mild AD but not in those with MCI. In the latter case, the authors cannot speak of true anosognosia but only of decreased awareness of illness. Furthermore, reduced awareness of cognitive difficulties is linked with verbal memory performances in patients with MCI but not in those with AD, suggesting for the latter the involvement of factors other than neuropsychological. Thus, neuropsychiatric dimensions commonly present in patients with AD should be investigated along with anosognosia.
MacDonald, Sheila
2016-01-01
Childhood acquired brain injuries can disrupt communication functions needed for success in school, work and social interaction. Cognitive-communication difficulties may not be apparent until adolescence, when academic, environmental and social-emotional demands increase. The Functional Assessment of Verbal Reasoning and Executive Strategies for Students (S-FAVRES) is a new activity-level measure of cognitive-communication skills in complex, contextual and integrative tasks that simulate real world communication challenges. It is hypothesized that S-FAVRES performance would differentiate adolescents with and without acquired brain injury (ABI) on scores for Accuracy, Rationale, Reasoning Subskills and Time. S-FAVRES was administered to 182 typically-developing (TD) and 57 adolescents with mild-to-severe ABI aged 12-19. Group differences, internal consistency, sensitivity, specificity, reliability and contributing factors to performance (age, gender, brain injury) were examined statistically. Those with ABI attained statistically lower Accuracy, Rationale and Reasoning sub-skills scores than their TD peers. Time scores were not significantly different. Performance trends were consistent across tasks, administrations, gender and age groups. Inter-rater reliability for scoring was acceptable. The S-FAVRES provides a reliable, functional and quantifiable measure of subtle cognitive-communication difficulties in adolescents that can assist speech-language pathologists in planning treatment and integration to school and real world communication.
A metamodel for mobile forensics investigation domain
Abd Razak, Shukor; Othman, Siti Hajar; Mohammed, Arafat; Saeed, Faisal
2017-01-01
With the rapid development of technology, mobile phones have become an essential tool in terms of crime fighting and criminal investigation. However, many mobile forensics investigators face difficulties with the investigation process in their domain. These difficulties are due to the heavy reliance of the forensics field on knowledge which, although a valuable resource, is scattered and widely dispersed. The wide dispersion of mobile forensics knowledge not only makes investigation difficult for new investigators, resulting in substantial waste of time, but also leads to ambiguity in the concepts and terminologies of the mobile forensics domain. This paper developed an approach for mobile forensics domain based on metamodeling. The developed approach contributes to identify common concepts of mobile forensics through a development of the Mobile Forensics Metamodel (MFM). In addion, it contributes to simplifying the investigation process and enables investigation teams to capture and reuse specialized forensic knowledge, thereby supporting the training and knowledge management activities. Furthermore, it reduces the difficulty and ambiguity in the mobile forensics domain. A validation process was performed to ensure the completeness and correctness of the MFM. The validation was conducted using two techniques for improvements and adjustments to the metamodel. The last version of the adjusted metamodel was named MFM 1.2. PMID:28445486
Schapkin, Sergei A; Falkenstein, Michael; Marks, Anke; Griefahn, Barbara
2006-04-01
The after-effects of nocturnal traffic noise on cognitive performance and inhibitory brain activity were investigated. Twenty participants (18-30 years) performed an easy and a difficult visual Go/Nogo task with simultaneous EEG recording after a quiet night and then during three nights when aircraft noise was presented with equivalent noise levels of 39, 44, and 50 dBA, respectively, between 11 p.m. to 7 a.m. Based on subjective sleep quality rating, participants were separated into "good" versus "bad" sleepers. The performance and inhibition-related components (N2, P3) of event-related potentials were analysed. The N2 and P3 amplitudes were smaller and latencies were prolonged in the difficult than in the easy task. This effect was more pronounced for Nogo than for Go trials. The Nogo-P3 amplitude was smaller in Noise than in "Quiet" conditions in the difficult task only. In the difficult task, the Nogo-P3 latency was prolonged in bad sleepers than in good sleepers. The Nogo-P3 amplitude was reduced in Noise as compared to "Quiet" conditions in bad sleepers only. Sleep quality in bad sleepers worsened steadily with increasing noise levels. No effects of noise or subjective sleep quality on performance were found. Inhibitory processes appear to be selectively impaired after nocturnal noise exposure. The task difficulty and perceived sleep quality are important factors modulating noise effects. The results suggest that nocturnal traffic noise increase physiological costs for inhibitory functioning on the day even if no overt performance decrement is observed.
Fostering Cognitive Growth Through Writing.
ERIC Educational Resources Information Center
Sternglass, Marilyn S.
Recent research studies and texts in composition demonstrate the growing belief that students' difficulties with the writing tasks assigned to them are inextricably linked with their difficulties in handling complex cognitive processes. Through appropriate writing activities, students can be provided with practice in the intellectual functions…
Mental workload associated with operating an agricultural sprayer: an empirical approach.
Dey, A K; Mann, D D
2011-04-01
Agricultural spraying involves two major tasks: guiding a sprayer in response to a GPS navigation device, and simultaneous monitoring of rear-attached booms under various illumination and terrain difficulty levels. The aim of the present study was to investigate the effect of illumination, task difficulty, and task level on the mental workload of an individual operating an agricultural sprayer in response to a commercial GPS lightbar, and to explore the sensitivity of the NASA-TLX and SSWAT subjective rating scales in discriminating the subjective experienced workload under various task, illumination, and difficulty levels. Mental workload was measured using performance measures (lateral root mean square error and reaction time), physiological measures (0.1 Hz power of HRV, latency of the P300 component of event-related potential, and eye-glance behavior), and two subjective rating scales (NASA-TLX and SSWAT). Sixteen male university students participated in this experiment, and a fixed-base high-fidelity agricultural tractor simulator was used to create a simulated spraying task. All performance measures, the P300 latency, and subjective rating scales showed a common trend that mental workload increased with the change in illumination from day to night, with task difficulty from low to high, and with task type from single to dual. The 0.1 Hz power of HRV contradicted the performance measures. Eye-glance data showed that under night illumination, participants spent more time looking at the lightbar for guidance information. A similar trend was observed with the change in task type from single to dual. Both subjective rating scales showed a common trend of increasing mental workload with the change in illumination, difficulty, and task levels. However, the SSWAT scale was more sensitive than the NASA-TLX scale. With the change in illumination, difficulty, and task levels, participants spent more mental resources to meet the increased task demand; hence, the illumination, task difficulty, and task level affected the mental workload of an agricultural sprayer operator operating a sprayer in response to a GPS lightbar.
Marshall, Paul W M; Desai, Imtiaz
2010-06-01
Although there is now some evidence examining the use of a Swiss ball during core stability and resistance exercises, this has commonly been performed using basic or isometric exercises. There is currently no evidence examining more advanced Swiss ball exercises. The purpose of this study was to determine whether or not muscle activity measured during advanced Swiss ball exercises was at an approximate intensity recommended for strength or endurance training in advanced, or novice individuals. After a familiarization session, 14 recreationally active subjects performed 6 different "advanced" Swiss ball exercises in a randomized order. The primary dependent variables in this study were the activity levels collected from anterior deltoid, pectoralis major, rectus abdominis (RA), external obliques, lumbar erector spinae, vastus lateralis (VL), and biceps femoris using surface electromyography. All signals were normalized to maximal voluntary isometric contractions performed before testing for each muscle. The results of this study showed that the Swiss ball roll elicited muscle activity in triceps brachii (72.5+/-32.4%) and VL (83.6+/-44.2%) commensurate with the intensity recommended for strength exercises in advanced trainers. Rectus abdominis activity was greatest during the bridge exercise (61.3+/-28.5%, p
Gross, M Melissa; Wright, Mary C; Anderson, Olivia S
2017-09-01
Research on the benefits of visual learning has relied primarily on lecture-based pedagogy, but the potential benefits of combining active learning strategies with visual and verbal materials on learning anatomy has not yet been explored. In this study, the differential effects of text-based and image-based active learning exercises on examination performance were investigated in a functional anatomy course. Each class session was punctuated with an average of 12 text-based and image-based active learning exercises. Participation data from 231 students were compared with their examination performance on 262 questions associated with the in-class exercises. Students also rated the helpfulness and difficulty of the in-class exercises on a survey. Participation in the active learning exercises was positively correlated with examination performance (r = 0.63, P < 0.001). When controlling for other key demographics (gender, underrepresented minority status) and prior grade point average, participation in the image-based exercises was significantly correlated with performance on examination questions associated with image-based exercises (P < 0.001) and text-based exercises (P < 0.01), while participation in text-based exercises was not. Additionally, students reported that the active learning exercises were helpful for seeing images of key ideas (94%) and clarifying key course concepts (80%), and that the image-based exercises were significantly less demanding, less hard and required less effort than text-based exercises (P < 0.05). The findings confirm the positive effect of using images and active learning strategies on student learning, and suggest that integrating them may be especially beneficial for learning anatomy. Anat Sci Educ 10: 444-455. © 2017 American Association of Anatomists. © 2017 American Association of Anatomists.
Player Modeling for Intelligent Difficulty Adjustment
NASA Astrophysics Data System (ADS)
Missura, Olana; Gärtner, Thomas
In this paper we aim at automatically adjusting the difficulty of computer games by clustering players into different types and supervised prediction of the type from short traces of gameplay. An important ingredient of video games is to challenge players by providing them with tasks of appropriate and increasing difficulty. How this difficulty should be chosen and increase over time strongly depends on the ability, experience, perception and learning curve of each individual player. It is a subjective parameter that is very difficult to set. Wrong choices can easily lead to players stopping to play the game as they get bored (if underburdened) or frustrated (if overburdened). An ideal game should be able to adjust its difficulty dynamically governed by the player’s performance. Modern video games utilise a game-testing process to investigate among other factors the perceived difficulty for a multitude of players. In this paper, we investigate how machine learning techniques can be used for automatic difficulty adjustment. Our experiments confirm the potential of machine learning in this application.
NASA-KSC/Florida Dual Use Technology Partnership
NASA Technical Reports Server (NTRS)
Kershaw, David
2001-01-01
This document constitutes the Technological Research and Development Authority's (TRDA) Final Reports for the NASA-KSC/Florida Dual Use Technology Partnership grant covering the period December 1, 1999 through November 30, 2000. The NASA Grant and Cooperative Agreement Handbook requires the TRDA to provide NASA with a final report on Subject Inventions, Federal Cash Transactions, Summary Research, and Federally-Owned Property. This report contains those requirements as well as a description of the TRDA's grant performance related to activities undertaken, difficulties incurred, remedial actions, and the current financial status of the contract.
Handwriting capacity in children newly diagnosed with Attention Deficit Hyperactivity Disorder.
Brossard-Racine, Marie; Majnemer, Annette; Shevell, Michael; Snider, Laurie; Bélanger, Stacey Ageranioti
2011-01-01
Preliminary evidence suggests that children with Attention Deficit Hyperactivity Disorder (ADHD) may exhibit handwriting difficulties. However, the exact nature of these difficulties and the extent to which they may relate to motor or behavioural difficulties remains unclear. The aim of this study was to describe handwriting capacity in children newly diagnosed with ADHD and identify predictors of performance. Forty medication-naïve children with ADHD (mean age 8.1 years) were evaluated with the Evaluation Tool of Children's Handwriting-Manuscript, the Movement Assessment Battery for Children (M-ABC), the Developmental Test of Visual Motor Integration (VMI) and the Conner Global Index. An important subset (85.0%) exhibited manual dexterity difficulties. Handwriting performance was extremely variable in terms of speed and legibility. VMI was the most important predictor of legibility. Upper extremity coordination, as measured by the M-ABC ball skills subtest, was also a good predictor of word legibility. Poor handwriting legibility and slow writing speed were common in children newly diagnosed with ADHD and were associated with motor abilities. Future studies are needed to determine whether interventions, including stimulant medications, can improve handwriting performance and related motor functioning. Copyright © 2011 Elsevier Ltd. All rights reserved.
Valla, Jeffrey M; Maendel, Jeffrey W; Ganzel, Barbara L; Barsky, Andrew R; Belmonte, Matthew K
2013-01-01
Autistic face processing difficulties are either uniquely social or due to a piecemeal cognitive "style." Co-morbidity of social deficits and piecemeal cognition in autism makes teasing apart these accounts difficult. These traits vary normally, and are more separable in the general population, suggesting another way to compare accounts. Participants completed the Autism Quotient survey of autistic traits, and one of three face recognition tests: full-face, eyes-only, or mouth-only. Social traits predicted performance in the full-face condition in both sexes. Eyes-only males' performance was predicted by a social × cognitive trait interaction: attention to detail boosted face recognition in males with few social traits, but hindered performance in those reporting many social traits. This suggests social/non-social Autism Spectrum Conditions (ASC) trait interactions at the behavioral level. In the presence of few ASC-like difficulties in social reciprocity, an ASC-like attention to detail may confer advantages on typical males' face recognition skills. On the other hand, when attention to detail co-occurs with difficulties in social reciprocity, a detailed focus may exacerbate such already present social difficulties, as is thought to occur in autism.
Fong, Tamara G; Gleason, Lauren J; Wong, Bonnie; Habtemariam, Daniel; Jones, Richard N; Schmitt, Eva M; de Rooij, Sophia E; Saczynski, Jane S; Gross, Alden L; Bean, Jonathan F; Brown, Cynthia J; Fick, Donna M; Gruber-Baldini, Ann L; O'Connor, Margaret; Tabloski, Patrica A; Marcantonio, Edward R; Inouye, Sharon K
2015-07-01
Difficulties with performance of functional activities may result from cognitive and/or physical impairments. To date, there has not been a clear delineation of the physical and cognitive demands of activities of daily living. To quantify the relative physical and cognitive demands required to complete typical functional activities in older adults. Expert panel survey. Web-based platform. Eleven experts from 8 academic medical centers and 300 community-dwelling elderly adults age 70 and older scheduled for elective noncardiac surgery from 2 academic medical centers. Sum scores of expert ratings were calculated and then validated against objective data collected from a prospective longitudinal study. Correlation between expert ratings and objective neuropsychologic tests (memory, language, complex attention) and physical measures (gait speed and grip strength) for performance-based tasks. Managing money, self-administering medications, using the telephone, and preparing meals were rated as requiring significantly more cognitive demand, whereas walking and transferring, moderately strenuous activities, and climbing stairs were assessed as more physically demanding. Largely cognitive activities correlated with objective neuropsychologic performance (r = 0.13-0.23, P < .05) and largely physical activities correlated with physical performance (r = 0.15-0.46, P < .05). Quantifying the degree of cognitive and/or physical demand for completing a specific task adds an additional dimension to standard measures of functional assessment. This additional information may significantly influence decisions about rehabilitation, postacute care needs, treatment plans, and caregiver education. Copyright © 2015 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
Investigation of PVdF active diaphragms for synthetic jets
NASA Astrophysics Data System (ADS)
Bailo, Kelly C.; Brei, Diann E.; Calkins, Frederick T.
2000-06-01
Current research has shown that aircraft can gain significant aerodynamic performance benefits by employing active flow control (AFC). One of the enabling technologies of AFC is the synthetic jet. Synthetic jets, also known as zero-net-mass flux actuators, act as bi-directional pumps injecting high momentum air into the local aerodynamic flow. Previous work has concentrated on high frequency synthetic jets based on piezoelectric active diaphragms such as Thunder actuators. Low frequency synthetic jets present a unique challenge requiring large displacements, which current technology has difficulty meeting. Boeing is investigating novel shaped low frequency synthetic jets that can modify the flow over fixed aircraft wings. This paper present the initial study of two promising active diaphragm concepts: a crescent shape and an opposing bender shape. These active diaphragms were numerically modeled utilizing the general-purpose finite element code ABAQUS. Using the ABAQUS results, the dynamic volume change within each jet was calculated and incorporated into an analytical linear Bernoulli model to predict the velocities and pressures at the nozzle. Simulations were performed to determine trends to assist in selection of prototype configurations. Prototypes of both diaphragm concepts were constructed from polyvinylidene fluoride and experimentally tested at Boeing with promising results.
International Atomic Energy Agency Safeguards: Challenge and response
NASA Astrophysics Data System (ADS)
Spector, Leonard S.
2017-11-01
This article provides a critical review of the nuclear accounting and inspection system of the International Atomic Energy Agency (IAEA), known as "IAEA safeguards." The article focuses on the multiple challenges the Agency confronts in verifying that all nuclear activities in the countries under its safeguards system are being pursued for exclusively peaceful purposes. The principal challenges noted are those posed by: undeclared facilities, the development of enrichment and reprocessing capabilities, illicit procurement activities, denial of inspector access, difficulties in verifying absence of weaponization activities, and difficulties in establishing that all nuclear-relevant activities in a state are peaceful. The article is in the form of annotated PowerPoint briefing slides.
Perceived importance and difficulty of online activities among visually impaired persons in Nigeria.
Okonji, Patrick Emeka; Okiki, Olatokunbo Christopher; Ogwezzy, Darlington
2018-03-26
This study investigated perceived relevance of and difficulties in access to day-to-day online activities among visually impaired computer users who used screen readers. The 98 participants in the study were grouped into visually impaired adults (aged 20-59, n = 60) and visually impaired older adults (aged 60 and over, n = 38). Data were collected in structured interview questionnaires with Likert scales exploring ratings of perceived importance and difficulty of access to 11 online platforms of various internet activities. Analyses revealed that the two groups did not differ significantly in ratings of perceived importance of four major online activities, namely sending or reading email (p = 0.5224), online banking (p = 0.2833), online shopping (p = 0.1829), and health information seeking (p = 0.1414). The topmost rated activity of priority among both groups was sending and reading emails. Findings also show that, apart from sending and reading emails, activities rated as important were mostly perceived as difficult to access. The implications of the study for inclusive design and strategies and/or interventions to encourage uptake of internet use among the visually impaired population are discussed.
Subjective rating scales as a workload
NASA Technical Reports Server (NTRS)
Bird, K. L.
1981-01-01
A multidimensional bipolar-adjective rating scale is employed as a subjective measure of operator workload in the performance of a one-axis tracking task. The rating scale addressed several dimensions of workload, including cognitive, physical, and perceptual task loading as well as fatigue and stress effects. Eight subjects performed a one-axis tracking task (with six levels of difficulty) and rated these tasks on several workload dimensions. Performance measures were tracking error RMS (root-mean square) and the standard deviation of control stick output. Significant relationships were observed between these performance measures and skill required, task complexity, attention level, task difficulty, task demands, and stress level.
No Fatigue Effect on Blink Rate
NASA Technical Reports Server (NTRS)
Kim, W.; Zangemeister, W.; Stark, L.
1984-01-01
Blink rate is reported to vary dependent upon ongoing task performance, perceptual, attentional and cognitive factors, and fatigue. Five levels of task difficulty were operationally defined and task performance as lines read aloud per minute were measured. A single noninvasive infrared TV eyetracker was modified to measure blinking and an on-line computer program identified and counted blinks while the subject performed the tasks. Blink rate decreased by 50% when either task performance increased (fast reading) or visual difficulty increased (blurred text); blink rate increased greatly during rest breaks. There was no change in blink rate during one hour experiments even though subjects complained of severe fatigue.
Jitendra, Asha K; Dupuis, Danielle N; Star, Jon R; Rodriguez, Michael C
2016-07-01
This study examined the effect of schema-based instruction (SBI) on the proportional problem-solving performance of students with mathematics difficulties only (MD) and students with mathematics and reading difficulties (MDRD). Specifically, we examined the responsiveness of 260 seventh grade students identified as MD or MDRD to a 6-week treatment (SBI) on measures of proportional problem solving. Results indicated that students in the SBI condition significantly outperformed students in the control condition on a measure of proportional problem solving administered at posttest (g = 0.40) and again 6 weeks later (g = 0.42). The interaction between treatment group and students' difficulty status was not significant, which indicates that SBI was equally effective for both students with MD and those with MDRD. Further analyses revealed that SBI was particularly effective at improving students' performance on items related to percents. Finally, students with MD significantly outperformed students with MDRD on all measures of proportional problem solving. These findings suggest that interventions designed to include effective instructional features (e.g., SBI) promote student understanding of mathematical ideas. © Hammill Institute on Disabilities 2014.
Moseley, Rachel L.; Shtyrov, Yury; Mohr, Bettina; Lombardo, Michael V.; Baron-Cohen, Simon; Pulvermüller, Friedemann
2015-01-01
Autism spectrum conditions (ASC) are characterised by deficits in understanding and expressing emotions and are frequently accompanied by alexithymia, a difficulty in understanding and expressing emotion words. Words are differentially represented in the brain according to their semantic category and these difficulties in ASC predict reduced activation to emotion-related words in limbic structures crucial for affective processing. Semantic theories view ‘emotion actions’ as critical for learning the semantic relationship between a word and the emotion it describes, such that emotion words typically activate the cortical motor systems involved in expressing emotion actions such as facial expressions. As ASC are also characterised by motor deficits and atypical brain structure and function in these regions, motor structures would also be expected to show reduced activation during emotion-semantic processing. Here we used event-related fMRI to compare passive processing of emotion words in comparison to abstract verbs and animal names in typically-developing controls and individuals with ASC. Relatively reduced brain activation in ASC for emotion words, but not matched control words, was found in motor areas and cingulate cortex specifically. The degree of activation evoked by emotion words in the motor system was also associated with the extent of autistic traits as revealed by the Autism Spectrum Quotient. We suggest that hypoactivation of motor and limbic regions for emotion word processing may underlie difficulties in processing emotional language in ASC. The role that sensorimotor systems and their connections might play in the affective and social-communication difficulties in ASC is discussed. PMID:25278250
Lam, H K; Leung, Frank H F
2007-10-01
This correspondence presents the stability analysis and performance design of the continuous-time fuzzy-model-based control systems. The idea of the nonparallel-distributed-compensation (non-PDC) control laws is extended to the continuous-time fuzzy-model-based control systems. A nonlinear controller with non-PDC control laws is proposed to stabilize the continuous-time nonlinear systems in Takagi-Sugeno's form. To produce the stability-analysis result, a parameter-dependent Lyapunov function (PDLF) is employed. However, two difficulties are usually encountered: 1) the time-derivative terms produced by the PDLF will complicate the stability analysis and 2) the stability conditions are not in the form of linear-matrix inequalities (LMIs) that aid the design of feedback gains. To tackle the first difficulty, the time-derivative terms are represented by some weighted-sum terms in some existing approaches, which will increase the number of stability conditions significantly. In view of the second difficulty, some positive-definitive terms are added in order to cast the stability conditions into LMIs. In this correspondence, the favorable properties of the membership functions and nonlinear control laws, which allow the introduction of some free matrices, are employed to alleviate the two difficulties while retaining the favorable properties of PDLF-based approach. LMI-based stability conditions are derived to ensure the system stability. Furthermore, based on a common scalar performance index, LMI-based performance conditions are derived to guarantee the system performance. Simulation examples are given to illustrate the effectiveness of the proposed approach.
Adolescent sleep disturbance and school performance: the confounding variable of socioeconomics.
Pagel, James F; Forister, Natalie; Kwiatkowki, Carol
2007-02-15
To assess how selected socioeconomic variables known to affect school performance alter the association between reported sleep disturbance and poor school performance in a contiguous middle school/high school population. A school district/college IRB approved questionnaire was distributed in science and health classes in middle school and high school. This questionnaire included a frequency scaled pediatric sleep disturbance questionnaire for completion by students and a permission and demographic questionnaire for completion by parents (completed questionnaires n = 238 with 69.3% including GPA). Sleep complaints occur at high frequency in this sample (sleep onset insomnia 60% > 1 x /wk.; 21.2% every night; sleepiness during the day (45.7% > 1 x /wk.; 15.2 % every night), and difficulty concentrating (54.6% > 1 x /wk.; 12.9% always). Students with lower grade point averages (GPAs) were more likely to have restless/aching legs when trying to fall asleep, difficulty concentrating during the day, snoring every night, difficulty waking in the morning, sleepiness during the day, and falling asleep in class. Lower reported GPAs were significantly associated with lower household incomes. After statistically controlling for income, restless legs, sleepiness during the day, and difficulty with concentration continued to significantly affect school performance. This study provides additional evidence indicating that sleep disturbances occur at high frequencies in adolescents and significantly affect daytime performance, as measured by GPA. The socioeconomic variable of household income also significantly affects GPA. After statistically controlling for age and household income, the number and type of sleep variables noted to significantly affect GPA are altered but persistent in demonstrating significant effects on school performance.
Patched bimetallic surfaces are active catalysts for ammonia decomposition
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo, Wei; Vlachos, Dionisios G.
In this study, ammonia decomposition is often used as an archetypical reaction for predicting new catalytic materials and understanding the very reason of why some reactions are sensitive on material’s structure. Core–shell or surface-segregated bimetallic nanoparticles expose outstanding activity for many heterogeneously catalysed reactions but the reasons remain elusive owing to the difficulties in experimentally characterizing active sites. Here by performing multiscale simulations in ammonia decomposition on various nickel loadings on platinum (111), we show that the very high activity of core–shell structures requires patches of the guest metal to create and sustain dual active sites: nickel terraces catalyse N-Hmore » bond breaking and nickel edge sites drive atomic nitrogen association. The structure sensitivity on these active catalysts depends profoundly on reaction conditions due to kinetically competing relevant elementary reaction steps. We expose a remarkable difference in active sites between transient and steady-state studies and provide insights into optimal material design.« less
Patched bimetallic surfaces are active catalysts for ammonia decomposition
Guo, Wei; Vlachos, Dionisios G.
2015-10-07
In this study, ammonia decomposition is often used as an archetypical reaction for predicting new catalytic materials and understanding the very reason of why some reactions are sensitive on material’s structure. Core–shell or surface-segregated bimetallic nanoparticles expose outstanding activity for many heterogeneously catalysed reactions but the reasons remain elusive owing to the difficulties in experimentally characterizing active sites. Here by performing multiscale simulations in ammonia decomposition on various nickel loadings on platinum (111), we show that the very high activity of core–shell structures requires patches of the guest metal to create and sustain dual active sites: nickel terraces catalyse N-Hmore » bond breaking and nickel edge sites drive atomic nitrogen association. The structure sensitivity on these active catalysts depends profoundly on reaction conditions due to kinetically competing relevant elementary reaction steps. We expose a remarkable difference in active sites between transient and steady-state studies and provide insights into optimal material design.« less
Xue, Linyan; Huang, Dan; Wang, Tong; Hu, Qiyi; Chai, Xinyu; Li, Liming; Chen, Yao
2017-11-28
Selective spatial attention enhances task performance at restricted regions within the visual field. The magnitude of this effect depends on the level of attentional load, which determines the efficiency of distractor rejection. Mechanisms of attentional load include perceptual selection and/or cognitive control involving working memory. Recent studies have provided evidence that microsaccades are influenced by spatial attention. Therefore, microsaccade activities may be exploited to help understand the dynamic control of selective attention under different load levels. However, previous reports in humans on the effect of attentional load on microsaccades are inconsistent, and it is not clear to what extent these results and the dynamic changes of microsaccade activities are similar in monkeys. We trained monkeys to perform a color detection task in which the perceptual load was manipulated by task difficulty with limited involvement of working memory. Our results indicate that during the task with high perceptual load, the rate and amplitude of microsaccades immediately before the target color change were significantly suppressed. We also found that the occurrence of microsaccades before the monkeys' detection response deteriorated their performance, especially in the hard task. We propose that the activity of microsaccades might be an efficacious indicator of the perceptual load.
Effects of occupational therapy on quality of life of patients with metastatic prostate cancer
Huri, Meral; Huri, Emre; Kayihan, Hulya; Altuntas, Onur
2015-01-01
Objectives: To evaluate the efficiency of occupational therapy relative to a home program in improving quality of life (QoL) among men who were treated for metastatic prostate cancer (MPC). Methods: Fifty-five men were assigned randomly to either the 12-week cognitive behavioral therapy based occupational therapy (OT-CBSM) intervention (treatment group) or a home program (control group) between March 2012 and August 2014 in the Department of Occupational Therapy, Faculty of Health Sciences, Hacettepe University, Ankara, Turkey. The Canadian Occupational Performance Measure (COPM) was used to measure the occupational performance and identify difficulties in daily living activities. The QoL and symptom status were measured by The European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire C30 and its Prostate Cancer Module. A 12-week OT-CBSM intervention including client-centered training of daily living activities, recreational group activities, and cognitive behavioral stress management intervention were applied. Results: The COPM performance and satisfaction scores, which indicate occupational participation and QoL increased statistically in the treatment group in relation to men who were included in the home-program (p≤0.05). Conclusion: A 12-week OT-CBSM intervention was effective in improving QoL in men treated for MPC, and these changes were associated significantly with occupational performance. PMID:26219446
Suicidal behaviour and psychosocial problems in veterinary surgeons: a systematic review.
Platt, Belinda; Hawton, Keith; Simkin, Sue; Mellanby, Richard J
2012-02-01
Rates of suicide are elevated among veterinary surgeons in several countries, yet little is known about contributory factors. We have conducted a systematic review of studies investigating suicidal behaviour and psychosocial problems in veterinary surgeons. A systematic search of the international research literature was performed in May 2008. Data from 52 studies of non-fatal suicidal behaviour, mental health difficulties, stress and burnout, occupational difficulties, and psychological characteristics of veterinary surgeons were extracted by two independent reviewers and analysed. Studies were rated for quality and greater emphasis placed on findings from higher quality studies. The majority of studies were of stress and occupational difficulties experienced by veterinary surgeons. Occupational stressors included managerial aspects of the job, long working hours, heavy workload, poor work-life balance, difficult client relations, and performing euthanasia. Few studies investigated suicidal behaviour or mental health difficulties in the profession. Some studies suggested that young and female veterinarians are at greatest risk of negative outcomes such as suicidal thoughts, mental health difficulties, and job dissatisfaction. The review highlights the difficulties faced by veterinary surgeons that may contribute to poor mental wellbeing and suicidal behaviour. Future research might include further examination of the influence of euthanasia on attitudes towards suicide and more direct examination of the impact that occupational risk factors might have on suicidal behaviour. Suggestions about the review's implications for suicide prevention in this group are also made.
Marín-Méndez, J J; Borra-Ruiz, M C; Álvarez-Gómez, M J; Soutullo Esperón, C
2017-10-01
ADHD symptoms begin to appear at preschool age. ADHD may have a significant negative impact on academic performance. In Spain, there are no standardized tools for detecting ADHD at preschool age, nor is there data about the incidence of this disorder. To evaluate developmental factors and learning difficulties associated with probable ADHD and to assess the impact of ADHD in school performance. We conducted a population-based study with a stratified multistage proportional cluster sample design. We found significant differences between probable ADHD and parents' perception of difficulties in expressive language, comprehension, and fine motor skills, as well as in emotions, concentration, behaviour, and relationships. Around 34% of preschool children with probable ADHD showed global learning difficulties, mainly in patients with the inattentive type. According to the multivariate analysis, learning difficulties were significantly associated with both delayed psychomotor development during the first 3 years of life (OR: 5.57) as assessed by parents, and probable ADHD (OR: 2.34) CONCLUSIONS: There is a connection between probable ADHD in preschool children and parents' perception of difficulties in several dimensions of development and learning. Early detection of ADHD at preschool ages is necessary to start prompt and effective clinical and educational interventions. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.
Departments: Problems and Alternatives.
ERIC Educational Resources Information Center
Faricy, William H.
This paper deals with the existing inter- and intra-departmental phenomena. Current practices of forming departments and aggregating departments into colleges are investigated and are shown to have inherent difficulties which inhibit the performance of a university. These difficulties are illustrated with empirical data from a representative set…
Transfer in motion perceptual learning depends on the difficulty of the training task.
Wang, Xiaoxiao; Zhou, Yifeng; Liu, Zili
2013-06-07
One hypothesis in visual perceptual learning is that the amount of transfer depends on the difficulty of the training and transfer tasks (Ahissar & Hochstein, 1997; Liu, 1995, 1999). Jeter, Dosher, Petrov, and Lu (2009), using an orientation discrimination task, challenged this hypothesis by arguing that the amount of transfer depends only on the transfer task but not on the training task. Here we show in a motion direction discrimination task that the amount of transfer indeed depends on the difficulty of the training task. Specifically, participants were first trained with either 4° or 8° direction discrimination along one average direction. Their transfer performance was then tested along an average direction 90° away from the trained direction. A variety of transfer measures consistently demonstrated that transfer performance depended on whether the participants were trained on 4° or 8° directional difference. The results contradicted the prediction that transfer was independent of the training task difficulty.
Stringer, P; Crown, S; Lucas, C J; Supramanium, S
1977-09-01
The personality correlates of study difficulty and academic performance in university students have been measured in terms of psychiatric symptomatology and premorbid characteristics. The UCLSQ, MHQ and DPI were administered to two groups of male and female students presenting at an health centre: one (n = 72) of patients seeking psychological help, the other (n = 73) a control group. Significant differences between the two groups were formed on the MHQ, confirming previous results; and these were supplemented by differences on the DPI. Motivational and psychoneurotic components of study difficulty were significantly related to MHQ scores in both groups. DPI scores were more closely related to study difficulty in the patients than controls; and served particularly to characterize their sylbism and work satisfaction. The DPI added to the picture of a subgroup of students observed both in an earlier and the present study: academically successful patients scoring high on phobic anxiety.
Kaneko, Masato; Uno, Akira; Haruhara, Noriko; Awaya, Noriko
2012-01-01
We investigated the usability and limitations of Rapid Automatized Naming (RAN) results in 6-year-old Japanese preschool children to estimate whether reading difficulties will be encountered after school entry. We administered a RAN task to 1,001 preschool children. Then after they had entered school, we performed follow-up surveys yearly to assess their reading performance when these children were in the first, second, third and fourth grades. Also, we examined Hiragana non-words and Kanji words at each time point to detect the children who were having difficulty with reading Hiragana and Kanji. Results by Receiver Operating Characteristic analysis showed that the RAN result in 6-year-old preschool children was predictive of Kanji reading difficulty in the lower grades of elementary school, especially in the second grade with a probability of 0.86, and the area under the curve showed a probability of 0.84 in the third grade. These results suggested that the RAN task was useful as a screening tool.
Monitoring of hearing and language in primary health care: project pilot.
Wagner, Julianne; Bonamigo, Andrea Wander; Oliveira, Fabiana de; Machado, Márcia Salgado
2017-11-01
This article analyzes the feasibility of implementing a program that monitors the hearing and language development in the first year of life. It is a prospective longitudinal study, in which 41 community health workers were invited to monitor, on a monthly basis, by means of a questionnaire validated earlier, the hearing and language of children born in their micro areas of expertise. Thirty-nine community health workers agreed to participate, with only two refusals. Five gave up participating. Twenty-six (66.66%) did not perform monitoring, seven (17.94%) monitored improperly and only six (15.38%) monitored properly. Just one child failed the quiz, who was forwarded to the hospital that conducted the auditory screening for retesting. These professionals' high activity demand was considered the main reason for the difficulties encountered in this project. In addition, there is the difficulty to have contact with the Family Health Strategy teams, as well as the impossibility of permanent face-to-face discussions and the influence of the community health agents' supervisors.
Branch, N G
1998-01-01
Society has an interest in maintaining the work capacity of its aging workers. Fewer and fewer younger workers are entering the workforce to replace older citizens no longer able to perform the worker role. There is a demonstrated relationship between increased strength and work capacity, yet the occupational therapy literature emphasizes generalized exercise programming. This type of programming is ineffective at building strength in the elderly worker. High intensity progressive resistance exercise (PRE) can increase strength in the very old worker, yet therapists are hesitant to employ PRE, perhaps due to a potential bias against the use of high intensity PRE with this cohort. Use of PRE may present some difficulties in the clinical situation where continual supervision and resistance training equipment is not available. The adaptive use of functional activities as a resistance training strategy to build strength may be able to overcome the difficulties attendant with the use of PRE while preserving its benefits. Several other implications for occupational therapy practitioners are discussed.
Evaluation of Chemical Coating Processes for AXAF
NASA Technical Reports Server (NTRS)
Engelhaupt, Darell; Ramsey, Brian; Mendrek, Mitchell
1998-01-01
The need existed at MSFC for the development and fabrication of radioisotope calibration sources of cadmium 109 and iron 55 isotopes. This was in urgent response to the AXA-F program. Several issues persisted in creating manufacturing difficulties for the supplier. In order to meet the MSFC requirements very stringent control needed to be maintained for the coating quality, specific activity and thickness. Due to the difficulties in providing the precisely controlled devices for testing, the delivery of the sources was seriously delayed. It became imperative that these fabrication issues be resolved to avoid further delays in this AXA-F observatory key component. The objectives are: 1) Research and provide expert advice on coating materials and procedures. 2) Research and recommend solutions to problems that have been experienced with the coating process. 3) Provide recommendations on the selection and preparation of substrates. 4) Provide consultation on the actual coating process including the results of the qualification and acceptance test programs. 5) Perform independent tests at UAH or MSFC as necessary.
Phenomenological analysis of densification mechanism during spark plasma sintering of MgAl2O4
NASA Astrophysics Data System (ADS)
Bernard-Granger, Guillaume; Benameur, Nassira; Addad, Ahmed; Nygren, Mats; Guizard, Christian; Deville, Sylvain
2009-05-01
Spark plasma sintering (SPS) of MgAl2O4 powder was investigated at temperatures between 1200 and 1300{\\deg}C. A significant grain growth was observed during densification. The densification rate always exhibits at least one strong minimum, and resumes after an incubation period. Transmission electron microscopy investigations performed on sintered samples never revealed extensive dislocation activity in the elemental grains. The densification mechanism involved during SPS was determined by anisothermal (investigation of the heating stage of a SPS run) and isothermal methods (investigation at given soak temperatures). Grain-boundary sliding, accommodated by an in-series {interface-reaction/lattice diffusion of the O$^2$-anions} mechanism controlled by the interface-reaction step, governs densification. The zero-densification-rate period, detected for all soak temperatures, arise from the difficulty of annealing vacancies, necessary for the densification to proceed. The detection of atomic ledges at grain boundaries and the modification of the stoichiometry of spinel during SPS could be related to the difficulty to anneal vacancies at temperature soaks.
Richmond, Rebecca C; Skugarevsky, Oleg; Yang, Seungmi; Kramer, Michael S; Wade, Kaitlin H; Patel, Rita; Bogdanovich, Natalia; Vilchuck, Konstantin; Sergeichick, Natalia; Smith, George Davey; Oken, Emily; Martin, Richard M
2014-01-01
Few studies have prospectively investigated associations of child cognitive ability and behavioural difficulties with later eating attitudes. We investigated associations of intelligence quotient (IQ), academic performance and behavioural difficulties at 6.5 years with eating attitudes five years later. We conducted an observational cohort study nested within the Promotion of Breastfeeding Intervention Trial, Belarus. Of 17,046 infants enrolled at birth, 13,751 (80.7%) completed the Children's Eating Attitude Test (ChEAT) at 11.5 years, most with information on IQ (n = 12,667), academic performance (n = 9,954) and behavioural difficulties (n = 11,098) at 6.5 years. The main outcome was a ChEAT score ≥ 85th percentile, indicative of problematic eating attitudes. Boys with higher IQ at 6.5 years reported fewer problematic eating attitudes, as assessed by ChEAT scores ≥ 85th percentile, at 11.5 years (OR per SD increase in full-scale IQ = 0.87; 0.79, 0.94). No such association was observed in girls (1.01; 0.93, 1.10) (p for sex-interaction = 0.016). In both boys and girls, teacher-assessed academic performance in non-verbal subjects was inversely associated with high ChEAT scores five years later (OR per unit increase in mathematics ability = 0.88; 0.82, 0.94; and OR per unit increase in ability for other non-verbal subjects = 0.86; 0.79, 0.94). Behavioural difficulties were positively associated with high ChEAT scores five years later (OR per SD increase in teacher-assessed rating = 1.13; 1.07, 1.19). Lower IQ, worse non-verbal academic performance and behavioural problems at early school age are positively associated with risk of problematic eating attitudes in early adolescence.
Regimen Difficulty and Medication Non-Adherence and the Interaction Effects of Gender and Age.
Dalvi, Vidya; Mekoth, Nandakumar
2017-12-08
Medication non-adherence is a global health issue. Numerous factors predict it. This study is aimed to identify the association between regimen difficulty and medication non-adherence among patients with chronic conditions and testing the interaction effects of gender and age on the same. It was a cross-sectional study conducted among 479 outpatients from India. Convenience sampling method was used. Multiple regression analyses were performed to find the predictors of non-adherence and to test interaction effects. Regimen difficulty predicted medication non-adherence. The patient's gender and age have interaction effects on the relationship between regimen difficulty and medication non-adherence.
Clarke, David
2017-01-01
Objective To review and synthesise qualitative literature relating to the longer-term needs of community dwelling stroke survivors with communication difficulties including aphasia, dysarthria and apraxia of speech. Design Systematic review and thematic synthesis. Method We included studies employing qualitative methodology which focused on the perceived or expressed needs, views or experiences of stroke survivors with communication difficulties in relation to the day-to-day management of their condition following hospital discharge. We searched MEDLINE, EMBASE, PsycINFO, CINAHL, The Cochrane Library, International Bibliography of the Social Sciences and AMED and undertook grey literature searches. Studies were assessed for methodological quality by two researchers independently and the findings were combined using thematic synthesis. Results Thirty-two studies were included in the thematic synthesis. The synthesis reveals the ongoing difficulties stroke survivors can experience in coming to terms with the loss of communication and in adapting to life with a communication difficulty. While some were able to adjust, others struggled to maintain their social networks and to participate in activities which were meaningful to them. The challenges experienced by stroke survivors with communication difficulties persisted for many years poststroke. Four themes relating to longer-term need were developed: managing communication outside of the home, creating a meaningful role, creating or maintaining a support network and taking control and actively moving forward with life. Conclusions Understanding the experiences of stroke survivors with communication difficulties is vital for ensuring that longer-term care is designed according to their needs. Wider psychosocial factors must be considered in the rehabilitation of people with poststroke communication difficulties. Self-management interventions may be appropriate to help this subgroup of stroke survivors manage their condition in the longer-term; however, such approaches must be designed to help survivors to manage the unique psychosocial consequences of poststroke communication difficulties. PMID:28988185
Solomon, Tracy L; Vasilyeva, Marina; Huttenlocher, Janellen; Levine, Susan C
2015-11-01
Understanding measurement units is critical to mathematics and science learning, but it is a topic that American students find difficult. In 3 studies, we investigated the challenges underlying this difficulty in kindergarten and second grade by comparing performance on different versions of a linear measurement task. Children measured crayons that were either aligned or shifted relative to the left edge of either a continuous ruler or a row of discrete units. The alignment (aligned, shifted) and the measuring tool (ruler, discrete units) were crossed to form 4 types of problems. Study 1 showed good performance in both grades on both types of aligned problems as well as on the shifted problems with discrete units. In contrast, performance was at chance on the shifted ruler problems. Study 2 showed that performance on shifted discrete unit problems declined when numbers were placed on the units, particularly for kindergarteners, suggesting that on the shifted ruler problems, the presence of numbers may have contributed to children's difficulty. However, Study 3 showed that the difficulty on the shifted ruler problems persisted even when the numbers were removed from the ruler. Taken together, these findings suggest that there are multiple challenges to understanding measurement, but that a key challenge is conceptualizing the ruler as a set of countable spatial interval units. (c) 2015 APA, all rights reserved).
Visual performance on detection tasks with double-targets of the same and different difficulty.
Chan, Alan H S; Courtney, Alan J; Ma, C W
2002-10-20
This paper reports a study of measurement of horizontal visual sensitivity limits for 16 subjects in single-target and double-targets detection tasks. Two phases of tests were conducted in the double-targets task; targets of the same difficulty were tested in phase one while targets of different difficulty were tested in phase two. The range of sensitivity for the double-targets test was found to be smaller than that for single-target in both the same and different target difficulty cases. The presence of another target was found to affect performance to a marked degree. Interference effect of the difficult target on detection of the easy one was greater than that of the easy one on the detection of the difficult one. Performance decrement was noted when correct percentage detection was plotted against eccentricity of target in both the single-target and double-targets tests. Nevertheless, the non-significant correlation found between the performance for the two tasks demonstrated that it was impossible to predict quantitatively ability for detection of double targets from the data for single targets. This indicated probable problems in generalizing data for single target visual lobes to those for multiple targets. Also lobe area values obtained from measurements using a single-target task cannot be applied in a mathematical model for situations with multiple occurrences of targets.
Dasgupta, Annwesa P; Anderson, Trevor R; Pelaez, Nancy
2014-01-01
It is essential to teach students about experimental design, as this facilitates their deeper understanding of how most biological knowledge was generated and gives them tools to perform their own investigations. Despite the importance of this area, surprisingly little is known about what students actually learn from designing biological experiments. In this paper, we describe a rubric for experimental design (RED) that can be used to measure knowledge of and diagnose difficulties with experimental design. The development and validation of the RED was informed by a literature review and empirical analysis of undergraduate biology students' responses to three published assessments. Five areas of difficulty with experimental design were identified: the variable properties of an experimental subject; the manipulated variables; measurement of outcomes; accounting for variability; and the scope of inference appropriate for experimental findings. Our findings revealed that some difficulties, documented some 50 yr ago, still exist among our undergraduate students, while others remain poorly investigated. The RED shows great promise for diagnosing students' experimental design knowledge in lecture settings, laboratory courses, research internships, and course-based undergraduate research experiences. It also shows potential for guiding the development and selection of assessment and instructional activities that foster experimental design. © 2014 A. P. Dasgupta et al. CBE—Life Sciences Education © 2014 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).
Natural history of Sanfilippo syndrome type A.
Buhrman, Dakota; Thakkar, Kavita; Poe, Michele; Escolar, Maria L
2014-05-01
To describe the natural history of Sanfilippo syndrome type A. We performed a retrospective review of 46 children (21 boys, 25 girls) with Sanfilippo syndrome type A evaluated between January 2000 and April 2013. Assessments included neurodevelopmental evaluations, audiologic testing, and assessment of growth, adaptive behavior, cognitive behavior, motor function, and speech/language skills. Only the baseline evaluation was included for patients who received hematopoietic stem cell transplantation. Median age at diagnosis was 35 months, with a median delay between initial symptoms to diagnosis of 24 months. The most common initial symptoms were speech/language delay (48%), dysmorphology (22%), and hearing loss (20%). Early behavioral problems included perseverative chewing and difficulty with toilet training. All children developed sleep difficulties and behavioral changes (e.g., hyperactivity, aggression). More than 93% of the children experienced somatic symptoms such as hepatomegaly (67%), abnormal dentition (39%), enlarged tongue (37%), coarse facial features (76%), and protuberant abdomen (43%). Kaplan-Meier analysis showed a 60% probability of surviving past 17 years of age. Sanfilippo type A is characterized by severe hearing loss and speech delay, followed by a rapid decline in cognitive skills by 3 years of age. Significant somatic disease occurs in more than half of patients. Behavioral difficulties presented between 2 and 4 years of age during a rapid period of cognitive decline. Gross motor abilities are maintained during this period, which results in an active child with impaired cognition. Sleep difficulties are concurrent with the period of cognitive degeneration. There is currently an unacceptable delay in diagnosis, highlighting the need to increase awareness of this disease among clinicians.
The analysis of 146 patients with difficult laparoscopic cholecystectomy.
Bat, Orhan
2015-01-01
Laparoscopic cholecystectomy (LC) is very commonly performed surgical intervention. Acute or chronic cholecystitis, adhesions due to previous upper abdomen surgeries, Mirrizi's syndrome and obesity are common clinical conditions that can be associated with difficult cholecystectomy. In this study, we evaluated and scored the patients with difficult surgical exploration during laparoscopic cholecystectomy. All patients who underwent LC from 2010 to 2015 were retrospectively rewieved. According to intraoperative findings DLC cases were described and classified. Class I difficulty: Adhesion of omentum majus, transverse colon, duodenum to the fundus of the gallbladder. Class II difficulty: Adhesions in Calot's triangle and difficulty in dissection of cystic artery and cystic duct Class III difficulty: Difficulty in dissection of gallbladder bed (scleroathrophic gallbladder, hemorrhage from liver during dissection of gallbladder, chirotic liver). Class IV difficulty: Difficulty in exploration of gallbladder due to intraabdominal adhesions including technical problems. A total of 146 patients were operated with DLC. The most common difficulty type was Class I difficulty (88 patients/60.2%). Laparoscopic cholecystectomy was converted to laparotomy in 98 patients. Operation time was found to be related with conversion to open surgery (P<0.05). Wound infection rate was also statistically higher in conversion group (P<0.05). The opertion time was found to be longest with Class II difficulty. Conversion rate to open surgery was also highest with Class II difficulty group. Class II difficulty characterized by severe adhesions in calot's triangle is most serious problem among all DLC cases. They have longer operation time and higher conversion rate.
GT-CATS: Tracking Operator Activities in Complex Systems
NASA Technical Reports Server (NTRS)
Callantine, Todd J.; Mitchell, Christine M.; Palmer, Everett A.
1999-01-01
Human operators of complex dynamic systems can experience difficulties supervising advanced control automation. One remedy is to develop intelligent aiding systems that can provide operators with context-sensitive advice and reminders. The research reported herein proposes, implements, and evaluates a methodology for activity tracking, a form of intent inferencing that can supply the knowledge required for an intelligent aid by constructing and maintaining a representation of operator activities in real time. The methodology was implemented in the Georgia Tech Crew Activity Tracking System (GT-CATS), which predicts and interprets the actions performed by Boeing 757/767 pilots navigating using autopilot flight modes. This report first describes research on intent inferencing and complex modes of automation. It then provides a detailed description of the GT-CATS methodology, knowledge structures, and processing scheme. The results of an experimental evaluation using airline pilots are given. The results show that GT-CATS was effective in predicting and interpreting pilot actions in real time.
Development of an Active Twist Rotor for Wind: Tunnel Testing (NLPN97-310
NASA Technical Reports Server (NTRS)
Cesnik, Carlos E. S.; Shin, SangJoon; Hagood, Nesbitt W., IV
1998-01-01
The development of the Active Twist Rotor prototype blade for hub vibration and noise reduction studies is presented in this report. Details of the modeling, design, and manufacturing are explored. The rotor blade is integrally twisted by direct strain actuation. This is accomplished by distributing embedded piezoelectric fiber composites along the span of the blade. The development of the analysis framework for this type of active blade is presented. The requirements for the prototype blade, along with the final design results are also presented. A detail discussion on the manufacturing aspects of the prototype blade is described. Experimental structural characteristics of the prototype blade compare well with design goals, and preliminary bench actuation tests show lower performance than originally predicted. Electrical difficulties with the actuators are also discussed. The presented prototype blade is leading to a complete fully articulated four-blade active twist rotor system for future wind tunnel tests.
Pain as a Risk Factor for Disability or Death
Andrews, James S.; Cenzer, Irena Stijacic; Yelin, Edward; Covinsky, Kenneth E.
2013-01-01
OBJECTIVES To determine whether pain predicts future activity of daily living (ADL) disability or death in individuals aged 60 years and above. DESIGN Prospective cohort study SETTING The 1998 to 2008 Health and Retirement Study (HRS), a nationally-representative study of older community-living individuals. PARTICIPANTS Twelve thousand six hundred and thirty-one participants in the 1998 HRS aged 60 years and older who did not need help in any activity of daily living (ADL). MEASUREMENTS Participants reporting that they were troubled by moderate or severe pain most of the time were defined as having significant pain. Our primary outcome was time to development of ADL disability or death over 10 years, assessed in 5 successive 2 year intervals. ADL disability was defined as needing help performing any ADL: bathing, dressing, transferring, toileting, eating, or walking across a room. We used a discrete hazards survival model to examine the relationship between pain and incident disability over each two year interval using only participants who started the interval with no ADL disability. We adjusted for several potential confounders at the start of each interval: demographic factors, 7 chronic health conditions, and functional limitations (ADL difficulty, and difficulty with 5 measures of mobility). RESULTS At baseline, 2,283 (18%) subjects had significant pain. Subjects with pain were more likely (all p<0.001) to be female (65% vs. 54%), have ADL difficulty (eg. transferring 12% vs. 2%, toileting 11% vs. 2%), have difficulty walking several blocks (60% vs. 21%), and have difficulty climbing one flight of stairs (40% vs. 12%). Over 10 years, subjects with pain were more likely to develop ADL disability or death (58% vs43%, unadjusted HR 1.67, 95% confidence interval (1.57 to 1.79)). However, after adjustment for confounders, participants with pain were not at increased risk for ADL disability or death (HR 0.98 (0.91 to 1.07)). The difference between the unadjusted and adjusted results was almost entirely explained by adjustment for functional status. CONCLUSION While there are strong cross-sectional relationships between pain and functional limitations, individuals with pain are not at higher risk for subsequent disability or death, after accounting for functional limitations. Like many geriatric syndromes, pain and disability may represent interrelated phenomena that occur simultaneously and require unified treatment paradigms. PMID:23521614
Wloch, Elizabeth G; Kuh, Diana; Cooper, Rachel
2016-01-01
Difficulties performing a range of physical tasks of daily living have been shown to develop in older populations in a typically observed sequence, known as the hierarchy of loss. Nearly all previous research has been undertaken using populations aged over 75. This study aimed to use cross-sectional and longitudinal data to test for evidence of the hierarchy of loss from midlife onwards. The prevalence of reported difficulty undertaking 16 physical tasks in the MRC National Survey of Health and Development at age 60-64 were calculated, with Mokken scaling used to confirm the hierarchical order. Logistic regression was used to calculate the odds ratios of reporting difficulty performing tasks at the bottom of the hierarchy (i.e. feeding, washing and/or toileting) at age 60-64 by reported difficulty at the top of the hierarchy (i.e. gripping, walking and/or stair climbing) at age 43. At age 60-64, tasks associated with balance, strength and co-ordination, such as climbing stairs, were the first tasks participants reported difficulty with and tasks associated with upper limb mobility, such as feeding yourself, were the last. In a fully-adjusted model, participants who reported difficulty at the top of the hierarchy at age 43 were 2.85 (95% CI: 1.45-5.60) times more likely to report difficulty with tasks at the bottom of the hierarchy at age 60-64. This study presents evidence of the hierarchy of loss in a younger population than previously observed suggesting that targeted interventions to prevent functional decline should not be delayed until old age.
Gounden, Yannick; Lacot, Emilie; Couvillers, Frédérique; Lions, Amandine; Hainselin, Mathieu
2016-01-01
Objective The autonomy of individuals is linked to the achievement of instrumental activities of daily living that require complex behavior. In the elderly, the assessment of autonomy is usually based on questionnaires that have strong subjective constraints. Considering this fact, we tested elderly healthy adults and Alzheimer disease patients using a new measure, the S-IADL (Simulation of Instrumental Activities for Daily Living), to assess the ability to perform effectively activities of daily living. Method The S-IADL shares many items with the well-known IADL questionnaire proposed by Lawton & Brody (1969). However, as opposed to the IADL, the assessment of autonomy is not based on the completion of a questionnaire but requires the realization or simulation of various activities of daily living. Eighty-three participants (69 healthy elderly, and 14 Alzheimer Disease patients) completed the IADL and performed the S-IADL assessment. Results Results revealed that, like the IADL, the S-IADL is able to identify AD patients who are likely to encounter difficulties in performing everyday activities, and no major differences were found between the IADL and the S-IADL. Conclusions We outlined some advantages for prefering, in certain situation, this new tool based on simulation of activities in functional evaluation. Finally, we discuss the main limits of the S-IADL that should be investigated prior to its utilization by clinicians. PMID:27672491
ADHD: Behavioral, Educational, and Medication Interventions
ERIC Educational Resources Information Center
DuPaul, George J.; White, George P.
2006-01-01
Attention-deficit/hyperactivity disorder (ADHD) is a disruptive behavior disorder which is characterized by levels of inattention (e.g., difficulty in concentrating on schoolwork), impulsivity (e.g., frequently interrupting conversations or activities), and/or overactivity (e.g., difficulty remaining seated when required to do so) that are well…
Difficulties in Initial Algebra Learning in Indonesia
ERIC Educational Resources Information Center
Jupri, Al; Drijvers, Paul; van den Heuvel-Panhuizen, Marja
2014-01-01
Within mathematics curricula, algebra has been widely recognized as one of the most difficult topics, which leads to learning difficulties worldwide. In Indonesia, algebra performance is an important issue. In the Trends in International Mathematics and Science Study (TIMSS) 2007, Indonesian students' achievement in the algebra domain was…
Investigation of Neural Strategies of Visual Search
NASA Technical Reports Server (NTRS)
Krauzlis, Richard J.
2003-01-01
The goal of this project was to measure how neurons in the superior colliculus (SC) change their activity during a visual search task. Specifically, we proposed to measure how the activity of these neurons was altered by the discriminability of visual targets and to test how these changes might predict the changes in the subjects performance. The primary rationale for this study was that understanding how the information encoded by these neurons constrains overall search performance would foster the development of better models of human performance. Work performed during the period supported by this grant has achieved these aims. First, we have recorded from neurons in the superior colliculus (SC) during a visual search task in which the difficulty of the task and the performance of the subject was systematically varied. The results from these single-neuron physiology experiments shows that prior to eye movement onset, the difference in activity across the ensemble of neurons reaches a fixed threshold value, reflecting the operation of a winner-take-all mechanism. Second, we have developed a model of eye movement decisions based on the principle of winner-take-all . The model incorporates the idea that the overt saccade choice reflects only one of the multiple saccades prepared during visual discrimination, consistent with our physiological data. The value of the model is that, unlike previous models, it is able to account for both the latency and the percent correct of saccade choices.
The effect of visual-motion time delays on pilot performance in a pursuit tracking task
NASA Technical Reports Server (NTRS)
Miller, G. K., Jr.; Riley, D. R.
1976-01-01
A study has been made to determine the effect of visual-motion time delays on pilot performance of a simulated pursuit tracking task. Three interrelated major effects have been identified: task difficulty, motion cues, and time delays. As task difficulty, as determined by airplane handling qualities or target frequency, increases, the amount of acceptable time delay decreases. However, when relatively complete motion cues are included in the simulation, the pilot can maintain his performance for considerably longer time delays. In addition, the number of degrees of freedom of motion employed is a significant factor.
Clark, David J; Chatterjee, Sudeshna A; McGuirk, Theresa E; Porges, Eric C; Fox, Emily J; Balasubramanian, Chitralakshmi K
2018-02-01
Walking adaptability tasks are challenging for people with motor impairments. The construct of perceived challenge is typically measured by self-report assessments, which are susceptible to subjective measurement error. The development of an objective physiologically-based measure of challenge may help to improve the ability to assess this important aspect of mobility function. The objective of this study to investigate the use of sympathetic nervous system (SNS) activity measured by skin conductance to gauge the physiological stress response to challenging walking adaptability tasks in people post-stroke. Thirty adults with chronic post-stroke hemiparesis performed a battery of seventeen walking adaptability tasks. SNS activity was measured by skin conductance from the palmar surface of each hand. The primary outcome variable was the percent change in skin conductance level (ΔSCL) between the baseline resting and walking phases of each task. Task difficulty was measured by performance speed and by physical therapist scoring of performance. Walking function and balance confidence were measured by preferred walking speed and the Activities-specific Balance Confidence Scale, respectively. There was a statistically significant negative association between ΔSCL and task performance speed and between ΔSCL and clinical score, indicating that tasks with greater SNS activity had slower performance speed and poorer clinical scores. ΔSCL was significantly greater for low functioning participants versus high functioning participants, particularly during the most challenging walking adaptability tasks. This study supports the use of SNS activity measured by skin conductance as a valuable approach for objectively quantifying the perceived challenge of walking adaptability tasks in people post-stroke. Published by Elsevier B.V.
Clark, David J.; Chatterjee, Sudeshna A.; McGuirk, Theresa E.; Porges, Eric C.; Fox, Emily J.; Balasubramanian, Chitralakshmi K.
2018-01-01
Background Walking adaptability tasks are challenging for people with motor impairments. The construct of perceived challenge is typically measured by self-report assessments, which are susceptible to subjective measurement error. The development of an objective physiologically-based measure of challenge may help to improve the ability to assess this important aspect of mobility function. The objective of this study to investigate the use of sympathetic nervous system (SNS) activity measured by skin conductance to gauge the physiological stress response to challenging walking adaptability tasks in people post-stroke. Methods Thirty adults with chronic post-stroke hemiparesis performed a battery of seventeen walking adaptability tasks. SNS activity was measured by skin conductance from the palmar surface of each hand. The primary outcome variable was the percent change in skin conductance level (ΔSCL) between the baseline resting and walking phases of each task. Task difficulty was measured by performance speed and by physical therapist grading of performance. Walking function and balance confidence were measured by preferred walking speed and the Activities Specific Balance Confidence Scale, respectively. Results There was a statistically significant negative association between ΔSCL and task performance speed and between ΔSCL and clinical score, indicating that tasks with greater SNS activity had slower performance speed and poorer clinical scores. ΔSCL was significantly greater for low functioning participants versus high functioning participants, particularly during the most challenging walking adaptability tasks. Conclusion This study supports the use of SNS activity measured by skin conductance as a valuable approach for objectively quantifying the perceived challenge of walking adaptability tasks in people post-stroke. PMID:29216598
Kulmala, Jenni; Ngandu, Tiia; Pajala, Satu; Lehtisalo, Jenni; Levälahti, Esko; Antikainen, Riitta; Laatikainen, Tiina; Oksa, Heikki; Peltonen, Markku; Rauramaa, Rainer; Soininen, Hilkka; Strandberg, Timo; Tuomilehto, Jaakko; Kivipelto, Miia
2016-10-01
Physical activity (PA) has beneficial effects on older age physical functioning, but longitudinal studies with follow-ups extending up to decades are few. We investigated the association between leisure-time PA (LTPA) and occupational PA (OPA) from early to late adulthood in relation to later life performance-based physical functioning. The study involved 1260 people aged 60 to 79 years who took part in assessments of physical functioning (Short Physical Performance Battery [SPPB] test, 10-m maximal walking test, and grip strength test). Participants' data on earlier life LTPA/OPA (age range 25 to 74 years) were received from the previous studies (average follow-up 13.4 years). Logistic, linear, and censored regression models were used to assess the associations between LTPA/OPA earlier in life and subsequent physical functioning. A high level of LTPA earlier in life was associated with a lower risk of having difficulties on the SPPB test (odds ratio [OR]: 0.37; 95% confidence interval [CI], 0.24-0.58) and especially on the chair rise test (OR: 0.42; 95% CI, 0.27-0.64) in old age. Heavy manual work predicted difficulties on SPPB (OR: 1.91; 95% CI, 1.22-2.98) and the chair rise test (OR: 1.75; 95% CI, 1.14-2.69) and poorer walking speed (β = .10, P = .005). This study highlights the importance of LTPA on later life functioning, but also indicates the inverse effects that may be caused by heavy manual work.
Neural Correlates of Emotion Regulation in Patients with Schizophrenia and Non-Affected Siblings
van der Velde, Jorien; Pijnenborg, Gerdina; Wiersma, Durk; Bruggeman, Richard; Aleman, André
2014-01-01
Background Patients with schizophrenia often experience problems regulating their emotions. Non-affected relatives show similar difficulties, although to a lesser extent, and the neural basis of such difficulties remains to be elucidated. In the current paper we investigated whether schizophrenia patients, non-affected siblings and healthy controls (HC) exhibit differences in brain activation during emotion regulation. Methods All subjects (n = 20 per group) performed an emotion regulation task while they were in an fMRI scanner. The task contained two experimental conditions for the down-regulation of emotions (reappraise and suppress), in which IAPS pictures were used to generate a negative affect. We also assessed whether the groups differed in emotion regulation strategies used in daily life by means of the emotion regulation questionnaire (ERQ). Results Though the overall negative affect was higher for patients as well as for siblings compared to HC for all conditions, all groups reported decreased negative affect after both regulation conditions. Nonetheless, neuroimaging results showed hypoactivation relative to HC in VLPFC, insula, middle temporal gyrus, caudate and thalamus for patients when reappraising negative pictures. In siblings, the same pattern was evident as in patients, but only in cortical areas. Conclusions Given that all groups performed similarly on the emotion regulation task, but differed in overall negative affect ratings and brain activation, our findings suggest reduced levels of emotion regulation processing in neural circuits in patients with schizophrenia. Notably, this also holds for siblings, albeit to a lesser extent, indicating that it may be part and parcel of a vulnerability for psychosis. PMID:24941136
Kindred, John H; Ketelhut, Nathaniel B; Rudroff, Thorsten
2015-02-01
Difficulties in ambulation are one of the main problems reported by patients with multiple sclerosis. A previous study by our research group showed increased recruitment of muscle groups during walking, but the influence of skeletal muscle properties, such as muscle fiber activity, has not been fully elucidated. The purpose of this investigation was to use the novel method of calculating glucose uptake heterogeneity in the leg muscles of patients with multiple sclerosis and compare these results to healthy controls. Eight patients with multiple sclerosis (4 men) and 8 healthy controls (4 men) performed 15 min of treadmill walking at a comfortable self-selected speed following muscle strength tests. Participants were injected with ≈ 8 mCi of [(18)F]-fluorodeoxyglucose during walking after which positron emission tomography/computed tomography imaging was performed. No differences in muscle strength were detected between multiple sclerosis and control groups (P>0.27). Within the multiple sclerosis, group differences in muscle volume existed between the stronger and weaker legs in the vastus lateralis, semitendinosus, and semimembranosus (P<0.03). Glucose uptake heterogeneity between the groups was not different for any muscle group or individual muscle of the legs (P>0.16, P≥0.05). Patients with multiple sclerosis and healthy controls showed similar muscle fiber activity during walking. Interpretations of these results, with respect to our previous study, suggest that walking difficulties in patients with multiple sclerosis may be more associated with altered central nervous system motor patterns rather than alterations in skeletal muscle properties. Published by Elsevier Ltd.
Hegde, Harihar V; Prasad, Kothegala C; Bhat, Manjunath T; Hegde, Jyothirmay S; Santhosh Mysore, C b; Yaliwal, Vijay G; Raghavendra Rao, P
2012-07-01
Assessment of Mallampati class is an integral part of preoperative airway evaluation. Increasing Mallampati class is known to be associated with greater difficulty with intubation, but some cases of airway difficulty in Mallampati 'class zero' patients have been reported. We undertook this study to evaluate intubation difficulty and to correlate this with indirect laryngoscopy findings in Mallampati class zero patients. The incidence of Mallampati class zero airway in Indian patients and the difficulty in mask ventilation were also evaluated. Prospective double-blind observational study. A tertiary care medical college hospital in Karnataka, India. September 2010 to April 2011. Patients of either sex, 18 years and older, presenting for preanaesthetic examination for elective surgery were evaluated. All patients with Mallampati class zero airway undergoing general anaesthesia with tracheal intubation were included. Exclusion criteria were upper airway disorder, unstable cervical spine, increased risk for aspiration, ischaemic heart disease, increased intracranial pressure, respiratory distress, those unable to sit upright, or infected with hepatitis B, hepatitis C, HIV or pulmonary tuberculosis, or requiring emergency surgery. All underwent indirect laryngoscopy performed by the otorhinolaryngologist and subsequently, direct laryngoscopy performed by the anaesthesiologist. Intubation difficulty was assessed by the Cormack & Lehane grades. Evaluation of intubation difficulty and correlation with indirect laryngoscopy findings in Mallampati class zero patients. Estimation of the incidence of Mallampati class zero airway in Indian patients and the difficulty in mask ventilation. Twenty women and thirteen men, aged 18-65 years, of Mallampati class zero were identified out of 1937 (incidence, 1.7%). The data of 27 patients were analysed. Two patients had 'difficult' mask ventilation. All had a 'predicted easy' airway on indirect laryngoscopy and 'easy' (Cormack & Lehane grade 1 or 2) tracheal intubation. Upon direct laryngoscopy, the epiglottis was described as 'large' in 10 (37%) patients. A Mallampati class zero per se is not associated with difficult airway unless other airway characteristics contribute to the difficulty. Even though the epiglottis may be large and overhanging, it rarely causes airway difficulty in Mallampati class zero airway.
Assessment of visual health campaign activities at schools: teachers' perception.
Carvalho, Regina de Souza; Temporini, Edméa Rita; Kara-José, Newton
2007-01-01
1) To assess the opinion of teachers involved in visual screening of school-age children and their referral to ophthalmologic examination within the "Eye-to-Eye National Campaign for Visual Disorders Prevention and Rehabilitation" (Campanha Nacional de Prevenção e Reabilitação Visual Olho no Olho); 2) To identify the teachers' perception with respect to the training received for conducting the campaign. A descriptive study has been conducted, based on data recorded from the application of a questionnaire to 1,517 elementary school teachers working in public schools in 27 Brazilian states. The following items were examined: received orientation, use of educational videos and handbooks, supplied explanations, difficulties, questions and overall campaign assessment. 82.0% of the teachers stated they had received orientation and 92.0% stated they had read the "Teacher Orientation Manual". Among those who received orientation, 47.0% stated it had been supplied by school officials; 30.0%, by healthcare agents, and 23.0% by ophthalmologists. In the self-assessment of performance, 58.0% reported no difficulties; 32.0% reported questions concerning the campaign activities and the professionals who most frequently asked to provide clarification were those from the State Education Agency (38.0%), followed by the school director (20.0%). Most teachers considered themselves adequately trained and oriented to take part in the campaign. Teachers' training was provided by administrative officials, previously trained by ophthalmologists ("multiplying effect") and the small percentage of questions raised indicated the validity of the procedure. Concerns have been raised as to the information about the ophthalmologic examination, transportation of the children and delivery of glasses. This kind of program always presents some difficulties and requires adjustments. It should, indeed, be improved, perhaps through a closer involvement of the community and families during its development.
Su, Brooke M; Park, Jason S; Chan, Dylan K
2017-10-01
Objective This study aims to describe the effects of primary language and insurance status on care utilization among deaf or hard-of-hearing children under active otolaryngologic and audiologic care. Study Design Cross-sectional analysis. Setting Multidisciplinary hearing loss clinic at a tertiary center. Subjects and Methods Demographics, hearing loss data, and validated survey responses were collected from 206 patients aged 0 to 19 years. Two-sided t tests and χ 2 tests were used to obtain descriptive statistics and hypothesis testing. Results Of the sample, 52.4% spoke primarily English at home. Non-English-speaking children and families were less likely to receive psychiatric counseling (12.2% vs 35.2% in the English group, P < .001) and reported more difficulty obtaining educational interventions ( P = .016), and 68.9% had public insurance. Parents of publicly insured children were less likely to know the type or degree of their child's hearing loss (56.9% vs 75.4%, P = .022), and these children were older on presentation to the clinic (8.5 vs 6.5 years of age, P = .01) compared to privately insured children. Publicly insured children were less likely to receive cochlear implants ( P = .046) and reported increased difficulty obtaining hearing aids ( P = .047). While all patients reported impairment in hearing-related quality of life, publicly insured children aged 2 to 7 years were more likely to perform below minimum thresholds on measures of auditory/oral functioning. Conclusion Even when under active care, deaf or hard-of-hearing children from families who do not speak English at home or with public insurance face more difficulty obtaining educational services, cochlear implants, and hearing aids. These findings represent significant disparities in access to necessary interventions.
Psychometric analyses to improve the Dutch ICF Activity Inventory.
Bruijning, Janna E; van Rens, Ger; Knol, Dirk; van Nispen, Ruth
2013-08-01
In the past, rehabilitation centers for the visually impaired used unstructured or semistructured methods to assess rehabilitation needs of their patients. Recently, an extensive instrument, the Dutch ICF Activity Inventory (D-AI), was developed to systematically investigate rehabilitation needs of visually impaired adults and to evaluate rehabilitation outcomes. The purpose of this study was to investigate the underlying factor structure and other psychometric properties to shorten and improve the D-AI. The D-AI was administered to 241 visually impaired persons who recently enrolled in a multidisciplinary rehabilitation center. The D-AI uses graded scores to assess the importance and difficulty of 65 rehabilitation goals. For high-priority goals (e.g., daily meal preparation), the difficulty of underlying tasks (e.g., read recipes, cut vegetables) was assessed. To reduce underlying task items (>950), descriptive statistics were investigated and factor analyses were performed for several goals. The internal consistency reliability and test-retest reliability of the D-AI were investigated by calculating Cronbach α and Cohen (weighted) κ. Finally, consensus-based discussions were used to shorten and improve the D-AI. Except for one goal, factor analysis model parameters were at least reasonable. Internal consistency reliability was satisfactory (range, 0.74 to 0.93). In total, 60% of the 65 goal importance items and 84.4% of the goal difficulty items showed moderate to almost perfect κ values (≥0.40). After consensus-based discussions, a new D-AI was produced, containing 48 goals and less than 500 tasks. The analyses were an important step in the validation process of the D-AI and to develop a more feasible assessment tool to investigate rehabilitation needs of visually impaired persons in a systematic way. The D-AI is currently implemented in all Dutch rehabilitation centers serving all visually impaired adults with various rehabilitation needs.
Ambrus, Livia; Lindqvist, Daniel; Träskman-Bendz, Lil; Westrin, Åsa
2016-11-01
Both decreased levels of brain-derived neurotrophic factor (BDNF) and hypothalamic-pituitary-adrenal (HPA) axis dysregulation may be involved in the pathophysiology of suicidal behaviour, as well as cognitive symptoms of depression. Pre-clinical and clinical studies have shown interactions between HPA-axis activity and BDNF, but this has not been studied in a clinical cohort of suicidal subjects. The purpose of this study was, therefore, to investigate associations between HPA-axis activity and BDNF in suicide attempters. Furthermore, this study examined the relationship between the HPA-axis, BDNF, and cognitive symptoms in suicidal patients. Since previous data indicate gender-related differences in BDNF and the HPA axis, males and females were examined separately. Seventy-five recent suicide attempters (n = 41 females; n = 34 males) were enrolled in the study. The Dexamethasone Suppression Test (DST) was performed and BDNF in plasma were analysed. Patients were evaluated with the Comprehensive Psychopathological Rating Scale (CPRS) from which items 'Concentration difficulties' and 'Failing memory' were extracted. Only among females, DST non-suppressors had significantly lower BDNF compared to DST suppressors (p = 0.022), and there was a significant correlation between post-DST serum cortisol at 8 a.m. and BDNF (rs = -0.437, p = 0.003). Concentration difficulties correlated significantly with post-DST cortisol in all patients (rs = 0.256, p = 0.035), in females (rs = 0.396, p = 0.015), and with BDNF in females (rs = -0.372, p = 0.020). The findings suggest an inverse relationship between the HPA-axis and BDNF in female suicide attempters. Moreover, concentration difficulties may be associated with low BDNF and DST non-suppression in female suicide attempters.
Velázquez Alva, María del Consuelo; Irigoyen Camacho, Maria Esther; Delgadillo Velázquez, Jaime; Lazarevich, Irina
2013-01-01
Sarcopenia is a geriatric syndrome, which affects the functional status and mobility of individuals. To identify the prevalence of sarcopenia and undernutrition, and to assess the association between sarcopenia and mobility, and sarcopenia and basic activities of daily living (ADL) in a group of elderly women. A cross-sectional study was performed in patients attending a geriatric service at a government hospital in Mexico City. Sarcopenia was identified applying Baumgartner's equation by obtaining skeletal muscle mass index (SMI) and undernutrition was diagnosed using mini-nutritional assessment instrument (MNA). The SENECA questionnaire and Katz index were used to evaluate mobility and ADL, respectively. lineal regression models were constructed fitting SMI as a dependent variable and SENECA, and ADL scores as independent variables, adjusted for age. 90 women with a mean age of 78.2 (± 6.8) were studied. Undernutrition was identified in 15.5% of the patients. The prevalence of sarcopenia was 41.1%. Patients with sarcopenia presented a high prevalence of undernutrition (p < 0.001). Sarcopenia was associated with difficulty in climbing stairs (OR = 2.63, p = 0.03), adjusted for age. The mobility score was associated with sarcopenia, in the group without sarcopenia the mean score was 16.3, and with sarcopenia it was 18.3, (p = 0.04). Regarding ADL, 64.9% of the patients with intermediate independence and dependence had sarcopenia, while 35.1% with total independence presented sarcopenia (p < 0.001). The elder women with sarcopenia had a higher prevalence of undernutrition. Sarcopenia was associated with difficulties in mobility, particularly difficulties in climbing stairs. Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.
Preissmann, Delphine; Charbonnier, Caecilia; Chagué, Sylvain; Antonietti, Jean-Philippe; Llobera, Joan; Ansermet, Francois; Magistretti, Pierre J.
2016-01-01
The feeling of synchrony is fundamental for most social activities and prosocial behaviors. However, little is known about the behavioral correlates of this feeling and its modulation by intergroup differences. We previously showed that the subjective feeling of synchrony in subjects involved in a mirror imitation task was modulated by objective behavioral measures, as well as contextual factors such as task difficulty and duration of the task performance. In the present study, we extended our methodology to investigate possible interindividual differences. We hypothesized that being in a romantic relationship or being a professional musician can modulate both implicit and explicit synchronization and the feeling of synchrony as well as the ability to detect synchrony from a third person perspective. Contrary to our hypothesis, we did not find significant differences between people in a romantic relationship and control subjects. However, we observed differences between musicians and control subjects. For the implicit synchrony (spontaneous synchronization during walking), the results revealed that musicians that had never met before spontaneously synchronized their movements earlier among themselves than control subjects, but not better than people sharing a romantic relationship. Moreover, in explicit behavioral synchronization tasks (mirror game), musicians reported earlier feeling of synchrony and had less speed errors than control subjects. This was in interaction with tasks difficulty as these differences appeared only in tasks with intermediate difficulty. Finally, when subjects had to judge synchrony from a third person perspective, musicians had a better performance to identify if they were present or not in the videos. Taken together, our results suggest that being a professional musician can play a role in the feeling of synchrony and its underlying mechanisms. PMID:27833580
Laverick, Rosanna; Haddow, Lewis; Daskalopoulou, Marina; Lampe, Fiona; Gilson, Richard; Speakman, Andrew; Antinori, Andrea; Bruun, Tina; Vassilenko, Anna; Collins, Simon; Rodger, Alison
2017-11-01
We determined factors associated with self-reported decline in activities of daily living (ADLs) and symptoms of cognitive impairment in HIV positive adults in 5 European clinics. HIV+ adults underwent computerized and pen-and-paper neuropsychological tests and questionnaires of cognitive symptoms and ADLs. We considered cognitive function in 5 domains, psychosocial factors, and clinical parameters as potentially associated with symptoms. Separate regression analyses were used to determine factors associated with a decline in ADL (defined as self-reported decline affecting ≥2 ADLs and attributed to cognitive difficulties) and self-reported frequency of symptoms of cognitive impairment. We also estimated the diagnostic accuracy of both questionnaires as tests for cognitive impairment. Four hundred forty-eight patients completed the assessments [mean age 45.8 years, 84% male, 87% white, median CD4 count 550 cells/mm, median time since HIV diagnosis 9.9 years, 81% virologically suppressed (HIV-1 plasma RNA <50 copies/mL)]. Ninety-six (21.4%) reported decline in ADLs and attributed this to cognitive difficulties. Self-reported decline in ADLs and increased symptoms of cognitive impairment were both associated with worse performance on some cognitive tests. There were also strong associations with financial difficulties, depressive and anxiety symptoms, unemployment, and longer time since HIV diagnosis. Both questionnaires performed poorly as diagnostic tests for cognitive impairment. Patients' own assessments of everyday function and symptoms were associated with objectively measured cognitive function. However, there were strong associations with other psychosocial issues including mood and anxiety disorders and socioeconomic hardship. This should be considered when assessing HIV-associated cognitive impairment in clinical care or research studies.
NASA Astrophysics Data System (ADS)
Noda, Itsuki; Stone, Peter; Yamashita, Tomohisa; Kurumatani, Koichi
While ambient intelligence and smart environments (AISE) technologies are expected to provide large impacts to human lives and social activities, it is generally difficult to show utilities and effects of these technologies on societies. AISE technologies are not only methods to improve performance and functionality of existing services in the society, but also frameworks to introduce new systems and services to the society. For example, no one expected beforehand what Internet or mobile phone brought into out social activities and services, although they changes our social system and patterns of behaviors drastically and emerge new services (and risks, unfortunately). The main reason of this difficulty is that actual effects of IT systems appear when enough number of people in the society use the technologies.
Disciplinary Knots and Learning Problems in Waves Physics
NASA Astrophysics Data System (ADS)
Di Renzone, Simone; Frati, Serena; Montalbano, Vera
An investigation on student understanding of waves is performed during an optional laboratory realized in informal extracurricular way with few, interested and talented pupils. The background and smart intuitions of students rendered the learning path very dynamic and ambitious. The activities started by investigating the basic properties of waves by means of a Shive wave machine. In order to make quantitative observed phenomena, the students used a camcorder and series of measures were obtained from the captured images. By checking the resulting data, it arose some learning difficulties especially in activities related to the laboratory. This experience was the starting point for a further analysis on disciplinary knots and learning problems in the physics of waves in order to elaborate a teaching-learning proposal on this topic.
Physical education issues for students with autism: school nurse challenges.
Rutkowski, Elaine M; Brimer, Debbie
2014-08-01
Extant studies indicate persons with autism have difficulties in social interaction, verbal and nonverbal communication, repetitive behaviors, and poor ability to generalize learned skills. Obesity has also been identified as significantly affecting children with autism spectrum disorders (ASD). Negative experience in physical education (PE) may be the antecedent behavior to lack of activities that are mediators to sedentary lifestyles and contributors to the chronic illnesses associated with overweight and obesity. Students with ASD often cannot perform required activities to meet required PE standards. It is imperative school nurses be aware of the many challenges students with ASD bring into a PE class. School nurses provide education for the members of the school community, including the Individualized Education Plan team, regarding the need for attention to limitations, including physical activity, of students with ASD. © The Author(s) 2013.
Attentional ability among survivors of leukaemia.
Rodgers, J; Horrocks, J; Britton, P G; Kernahan, J
1999-04-01
Attentional ability in 19 survivors of acute lymphoblastic leukaemia and 19 sibling controls was assessed using a neuropsychological model of attention. Analysis revealed that children who had received treatment for leukaemia exhibited significantly poorer performance on measures of the "focus encode" and "focus execute" elements of attention and on measures of the ability to respond to external cues and feedback. No significant differences in performance were found for measures of sustained attention and the ability to shift attention. These results indicate that children who have received treatment for leukaemia may experience highly specific attentional deficits that could have an impact on academic performance, particularly mathematical and reading skills. It is suggested that this underlying attentional deficit might be the source of the neuropsychological sequelae associated with the disease. Future attempts at remediation should incorporate activities specifically designed to ameliorate focusing difficulties.
ERIC Educational Resources Information Center
Gupta, Ayush; Elby, Andrew
2011-01-01
Researchers have argued against deficit-based explanations of students' difficulties with mathematical sense-making, pointing instead to factors such as epistemology. Students' beliefs about knowledge and learning can hinder the activation and integration of productive knowledge they have. Such explanations, however, risk falling into a…
A Preschool Program for Preventing Learning Difficulties in Arithmetic.
ERIC Educational Resources Information Center
Dunlap, William P.
Described are many concrete readiness activities within ten broad categories that are designed to provide children with a solid foundation for mathematics and that help prevent learning difficulties in mathematics. Preschool mathematical experiences form the foundation for all studies in mathematics. Without a sufficient number of appropriate…
77 FR 55216 - Agency Information Collection Activities: Proposed Collection; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-07
..., due to technical difficulties, the documents associated with the information collection request were not made available to the public until August 14, 2012. Because of the technical difficulties, CMS is... Social Security Act (SSA) requires Medicare health plans to provide enrollees with a written notice in...
Stress and Burden among Caregivers of Patients with Lewy Body Dementia
ERIC Educational Resources Information Center
Leggett, Amanda N.; Zarit, Steven; Taylor, Angela; Galvin, James E.
2011-01-01
Purpose: Patients with Lewy body dementia (LBD) may present a unique set of symptoms and challenges to family caregivers compared with other types of dementia. Prominent difficulties include motor impairment, activities of daily living (ADLs) disability, recurrent behavioral and emotional problems (BEPs), and diagnostic difficulties. These…
Identifying Student Difficulties with Entropy, Heat Engines, and the Carnot Cycle
ERIC Educational Resources Information Center
Smith, Trevor I.; Christensen, Warren M.; Mountcastle, Donald B.; Thompson, John R.
2015-01-01
We report on several specific student difficulties regarding the second law of thermodynamics in the context of heat engines within upper-division undergraduate thermal physics courses. Data come from ungraded written surveys, graded homework assignments, and videotaped classroom observations of tutorial activities. Written data show that students…
Sleep Difficulties and Academic Performance in Norwegian Higher Education Students
ERIC Educational Resources Information Center
Hayley, Amie C.; Sivertsen, Børge; Hysing, Mari; Vedaa, Øystein; Øverland, Simon
2017-01-01
Background: Sleep difficulties are common among university students and may detrimentally affect academic outcomes. Despite this, remarkably little information is currently available during this critical developmental period of early adulthood, and thus, the direct effect on measurable domains of academic ability and proficiency is equivocal.…
Equating with Miditests Using IRT
ERIC Educational Resources Information Center
Fitzpatrick, Joseph; Skorupski, William P.
2016-01-01
The equating performance of two internal anchor test structures--miditests and minitests--is studied for four IRT equating methods using simulated data. Originally proposed by Sinharay and Holland, miditests are anchors that have the same mean difficulty as the overall test but less variance in item difficulties. Four popular IRT equating methods…
Brain Regions Underlying Word Finding Difficulties in Temporal Lobe Epilepsy
ERIC Educational Resources Information Center
Trebuchon-Da Fonseca, Agnes; Guedj, Eric; Alario, F-Xavier; Laguitton, Virginie; Mundler, Olivier; Chauvel, Patrick; Liegeois-Chauvel, Catherine
2009-01-01
Word finding difficulties are often reported by epileptic patients with seizures originating from the language dominant cerebral hemisphere, for example, in temporal lobe epilepsy. Evidence regarding the brain regions underlying this deficit comes from studies of peri-operative electro-cortical stimulation, as well as post-surgical performance.…
ERIC Educational Resources Information Center
DuPaul, George J.; Jimerson, Shane R.
2014-01-01
Students with attention-deficit/hyperactivity disorder (ADHD) exhibit chronic behavior difficulties that deleteriously impact their academic and social functioning in school settings. These difficulties not only impair student performance, but also present significant challenges to teachers, school psychologists, and other school professionals…
Stress and Reading Difficulties: Research, Assessment, Intervention.
ERIC Educational Resources Information Center
Gentile, Lance M.; McMillan, Merna M.
Focusing on the personality of the reading disabled child, this booklet is designed to encourage researchers to move past the circular debate concerning student reading difficulties and to help teachers improve the reading performance of students with disabling stress reactions to reading. The first section examines research related to emotional…
Take the Pencil out of the Process
ERIC Educational Resources Information Center
Broun, Leslie
2009-01-01
In classrooms, it is not unusual to see students who struggle to produce legible print. In actuality, many students have difficulty with the physical printing and writing processes ("handwriting")--difficulty that is significant enough to interfere with their academic performance. Some students grow out of this, and some, with extra practice,…
Building Knowledge Structures by Testing Helps Children with Mathematical Learning Difficulty
ERIC Educational Resources Information Center
Zhang, Yiyun; Zhou, Xinlin
2016-01-01
Mathematical learning difficulty (MLD) is prevalent in the development of mathematical abilities. Previous interventions for children with MLD have focused on number sense or basic mathematical skills. This study investigated whether mathematical performance of fifth grade children with MLD could be improved by developing knowledge structures by…
Using Real-Life Experiences to Teach Computer Concepts
ERIC Educational Resources Information Center
Read, Alexis
2012-01-01
Teaching computer concepts to individuals with visual impairments (that is, those who are blind or visually impaired) presents some unique challenges. Students often have difficulty remembering to perform certain steps or have difficulty remembering specific keystrokes when using computers. Many cannot visualize the way in which complex computing…
Time Estimation Deficits in Childhood Mathematics Difficulties
ERIC Educational Resources Information Center
Hurks, Petra P. M.; van Loosbroek, Erik
2014-01-01
Time perception has not been comprehensively examined in mathematics difficulties (MD). Therefore, verbal time estimation, production, and reproduction were tested in 13 individuals with MD and 16 healthy controls, matched for age, sex, and intellectual skills. Individuals with MD performed comparably to controls in time reproduction, but showed a…
75 FR 29552 - Proposed Data Collections Submitted for Public Comment and Recommendations
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-26
... collection of information is necessary for the proper performance of the functions of the agency, including... of the Short Strengths and Difficulties Questionnaire (SDQ) in the National Health Interview Survey... and Difficulties Questionnaire (short SDQ), a module that has obtained data on the mental health of...
Teaching Mathematical Problem Solving to Students with Limited English Proficiency.
ERIC Educational Resources Information Center
Kaplan, Rochelle G.; Patino, Rodrigo A.
Many mainstreamed students with limited English proficiency continue to face the difficulty of learning English as a second language (ESL) while studying mathematics and other content areas framed in the language of native speakers. The difficulty these students often encounter in mathematics classes and their poor performance on subsequent…
D'Orso, M I; Giuliani, C; Assini, R; Riva, M A; Cesana, G
2012-01-01
Our research describes activities of Occupational Health carried out during last year in University of Milan Bicocca by Occupational Doctors. We describe results of medical surveillance in 1153 employees or students exposed to occupational risks for health and safety. We report results obtained, technical difficulties, organizational problems, and preventive actions decided to improve functionality of our activity. Students seem to be less protected and consequently seem to have higher professional safety and health risks.
A Longitudinal Examination of the Persistence of Late Emerging Reading Disabilities.
Etmanskie, Jill M; Partanen, Marita; Siegel, Linda S
2016-01-01
There are some children who encounter unexpected reading difficulties in the fourth grade. This phenomenon has been described as late emerging reading disabilities (LERD). Using Grade 4 as a starting point, this study examined the reading development of 964 children between kindergarten and Grade 7. The results showed that 72.0% of children had typical reading performance in Grade 4, whereas there was 0.7% with poor word reading, 12.6% with poor reading comprehension, 2.5% with poor word reading and comprehension, and 12.2% with borderline performance. We also showed that there were similar proportions of children who had early versus late emerging reading difficulties; however, most of the late emerging poor readers recovered by Grade 7. Furthermore, our study showed that poor comprehenders showed poorer performance than typical readers on word reading, pseudoword decoding, and spelling between Grade 1 and Grade 7 and poorer performance on a working memory task in kindergarten. Overall, this study showed that most children recover from late emerging reading problems and that working memory may be an early indicator for reading comprehension difficulties. © Hammill Institute on Disabilities 2014.