Science.gov

Sample records for active research tasks

  1. Materials processing in space programs tasks. [NASA research tasks

    NASA Technical Reports Server (NTRS)

    Pentecost, E.

    1981-01-01

    Active research tasks as of the end of fiscal year 1981 of the materials processing in space program, NASA Office of Space and Terrestrial Applications are summarized to provide an overview of the program scope for managers and scientists in industry, university, and government communities. The program, its history, strategy, and overall goal are described the organizational structures and people involved are identified and a list of recent publications is given for each research task. Four categories: Crystal Growth; Solidification of Metals, Alloys, and Composites; Fluids, Transports, and Chemical Processes, and Ultrahigh Vacuum and Containerless Processing Technologies are used to group the tasks. Some tasks are placed in more than one category to insure complete coverage of each category.

  2. JV Task 120 - Coal Ash Resources Research Consortium Research

    SciTech Connect

    Debra Pflughoeft-Hassett; Loreal Heebink; David Hassett; Bruce Dockter; Kurt Eylands; Tera Buckley; Erick Zacher

    2009-03-28

    The Coal Ash Resources Research Consortium{reg_sign} (CARRC{reg_sign}, pronounced 'cars') is the core coal combustion product (CCP) research group at the Energy & Environmental Research Center (EERC). CARRC focuses on performing fundamental and applied scientific and engineering research emphasizing the environmentally safe, economical use of CCPs. CARRC member organizations, which include utilities and marketers, are key to developing industry-driven research in the area of CCP utilization and ensuring its successful application. The U.S. Department of Energy is a partner in CARRC through the EERC Jointly Sponsored Research Program, which provides matching funds for industrial member contributions and facilitates an increased level of effort in CARRC. CARRC tasks were designed to provide information on CCP performance, including environmental performance, engineering performance, favorable economics, and improved life cycle of products and projects. CARRC technical research tasks are developed based on member input and prioritization. CARRC special projects are developed with members and nonmembers to provide similar information and to support activities, including the assembly and interpretation of data, support for standards development and technology transfer, and facilitating product development and testing. CARRC activities from 2007 to 2009 included a range of research tasks, with primary work performed in laboratory tasks developed to answer specific questions or evaluate important fundamental properties of CCPs. The tasks were included in four categories: (1) Environmental Evaluations of CCPs; (2) Evaluation of Impacts on CCPs from Emission Controls; (3) Construction and Product-Related Activities; and (4) Technology Transfer and Maintenance Tasks. All tasks are designed to work toward achieving the CARRC overall goal and supporting objectives. The various tasks are coordinated in order to provide broad and useful technical data for CARRC members. Special

  3. Advanced Materials for Exploration Task Research Results

    NASA Technical Reports Server (NTRS)

    Cook, M. B. (Compiler); Murphy, K. L.; Schneider, T.

    2008-01-01

    The Advanced Materials for Exploration (AME) Activity in Marshall Space Flight Center s (MSFC s) Exploration Science and Technology Directorate coordinated activities from 2001 to 2006 to support in-space propulsion technologies for future missions. Working together, materials scientists and mission planners identified materials shortfalls that are limiting the performance of long-term missions. The goal of the AME project was to deliver improved materials in targeted areas to meet technology development milestones of NASA s exploration-dedicated activities. Materials research tasks were targeted in five areas: (1) Thermal management materials, (2) propulsion materials, (3) materials characterization, (4) vehicle health monitoring materials, and (5) structural materials. Selected tasks were scheduled for completion such that these new materials could be incorporated into customer development plans.

  4. Activities of the Oil Implementation Task Force, December 1990--February 1991; Contracts for field projects and supporting research on enhanced oil recovery, April--June 1990

    SciTech Connect

    Tiedemann, H.A. )

    1991-03-01

    The Oil Implementation Task Force was appointed to implement the US DOE's new oil research program directed toward increasing domestic oil production by expanded research on near- or mid-term enhanced oil recovery methods. An added priority is to preserve access to reservoirs that have the largest potential for oil recovery, but that are threatened by the large number of wells abandoned each year. This report describes the progress of research activities in the following areas: chemical flooding; gas displacement; thermal recovery; resource assessment; microbial technology; geoscience technology; and environmental technology. (CK)

  5. Tasks of air flow research

    NASA Technical Reports Server (NTRS)

    Prandtl, L

    1926-01-01

    The researches at the Gottingen Institute are discussed especially in regards to the physical properties of fluids. The three main properties of fluids examined concern density, viscosity, and compressibility.

  6. JV Task 6 - Coal Ash Resources Research Consortium Research

    SciTech Connect

    Debra Pflughoeft-Hassett; Tera Buckley; Bruce Dockter; Kurt Eylands; David Hassett; Loreal Heebink; Erick Zacher

    2008-04-01

    The Coal Ash Resources Research Consortium{reg_sign} (CARRC{reg_sign}, pronounced 'cars') focuses on performing fundamental and applied scientific and engineering research emphasizing the environmentally safe, economical use of coal combustion by-products (CCBs). CARRC member organizations, which include utilities and marketers, are key to developing industry-driven research in the area of CCB utilization and ensuring its successful application. The U.S. Department of Energy is a partner in CARRC through the EERC Jointly Sponsored Research Program (JSRP), which provides matching funds for industrial member contributions and facilitates an increased level of effort in CARRC. CARRC tasks were designed to provide information on CCB performance, including environmental performance, engineering performance, favorable economics, and improved life cycle of products and projects. CARRC technical research tasks are developed based on member input and prioritization. CARRC special projects are developed with members and nonmembers to provide similar information and to support activities, including the assembly and interpretation of data, support for standards development and technology transfer, and facilitating product development and testing. CARRC activities from 1998 to 2007 included a range of research tasks, with primary work performed in laboratory tasks developed to answer specific questions or evaluate important fundamental properties of CCBs. CARRC topical reports were prepared on several completed tasks. Specific CARRC 1998B2007 accomplishments included: (1) Development of several ASTM International Standard Guides for CCB utilization applications. (2) Organization and presentation of training courses for CCB professionals and teachers. (3) Development of online resources including the Coal Ash Resource Center, Ash from Biomass in Coal (ABC) of cocombustion ash characteristics, and the Buyer's Guide to Coal-Ash Containing Products. In addition, development of

  7. “Astronomy for a Better World”: IAU/OAD Task Force One Activities to Develop Astronomy Education and Research at Universities in the Developing World

    NASA Astrophysics Data System (ADS)

    Guinan, Edward Francis; Kolenberg, Katrien

    2015-08-01

    The Task Force (1) on Astronomy for Universities & Research (TF-1) was established in 2012 as part of the IAU Office of Astronomy for Development (OAD). This Task Force drives activities related to astronomy education and research at universities mainly in the developing world. Astronomy is used to stimulate research and education in STEM fields and to develop and promote astronomy in regions of the world where there is little or no astronomy. There is also potential for developing research in the historical and cultural aspects of astronomy which may prove important for stimulating an interest in the subject in communities where there is yet no established interest in the science.Since the establishment of the OAD, over 25 TF-1 programs have been funded (or partially funded) to support a wide variety of interesting and innovative astronomy programs in Africa, Asia, South-East Asia, Middle-East, and in South & Central America. Nearly every aspect of development has been supported. These programs include supporting: regional astronomy training schools, specialized workshops, research visits, university twinning programs, distance learning projects, university astronomy curriculum development, as well as small telescope and equipment grants. In addition, a large new program - Astrolab - was introduced (by J-P De Greve and Michele Gerbaldi) to bring starlight” into the class room. In the Astrolab program students carry out and reduce CCD photometry secured by them using remotely controlled telescopes. Results from pilot programs will be discussed.OAD TF-1 programs will be discussed along with future plans for improving and expanding these programs to bring astronomy education and research to a greater number of people and indeed to use Astronomy for a Better World. Information and advice will also be provided about applying for support in the future.

  8. Minnesota Agripower Project, Task IV research report

    SciTech Connect

    Fruin, J.; Tiffany, D.

    1997-10-30

    Economic analysis is being conducted by the Department of Applied Economics in support of Minnesota Alfalfa Producer`s development of alfalfa as a dedicated biomass feedstock for energy production. University Researchers have assisted in the development and implementation of inventory control systems and procedures. This report lists the tasks for which researchers are currently finalizing economic analysis. The tasks encompass three main areas: (1) optimization of feedstock transportation system, (2) analysis of market potential for new alfalfa products, and (3) total systems analysis.

  9. Understanding of Student Task Interpretation, Design Planning, and Cognitive Strategies during Engineering Design Activities in Grades 9-12. Final Report. Research in Engineering and Technology Education

    ERIC Educational Resources Information Center

    Lawanto, Oenardi

    2011-01-01

    The objective of this study was to describe the task interpretation of students engaged in a design activity and determine the extent to which students translate their understanding of their design task to their planning and cognitive strategies. Twenty-nine students at one Colorado high school participated in this study. Students worked…

  10. Task Descriptions in Diagnostic Radiology. Research Report No. 7. Volume 2, Radiologic Technologist Tasks Dealing with Patient Procedures. Part I: Tasks 7 through 386.

    ERIC Educational Resources Information Center

    Gilpatrick, Eleanor

    Part I of the second of four volumes in Research Report No. 7 of the Health Services Mobility Study (HSMS), this book contains 76 task descriptions covering most of the medical activities carried out by radiologic technologists. Chapter I of this volume defines "tasks" and tells how the descriptions were developed. Chapter 2 lists the tasks by…

  11. Human task-specific somatosensory activation.

    PubMed

    Ginsberg, M D; Yoshii, F; Vibulsresth, S; Chang, J Y; Duara, R; Barker, W W; Boothe, T E

    1987-08-01

    We used positron emission tomography to study normal patterns of local cortical metabolic activation induced by somatosensory stimuli. Palpation and sorting of mah-jongg tiles by textured design increased local glucose metabolic rate (lCMRgl), by 18% on average, in contralateral somatosensory cortex. A graphesthesia task gave a similar result. In contrast, vigorous vibrotactile stimulation of fingers, face, or knee did not produce a consistent focus of activation. Our results indicate that lCMRgl activation is best achieved by somatosensory tasks requiring an active perceptual effort.

  12. Selecting and Creating Mathematical Tasks: From Research To Practice.

    ERIC Educational Resources Information Center

    Smith, Margaret Schwan; Stein, Mary Kay

    1998-01-01

    Focuses on the selection and creation of mathematical tasks, drawing on QUASAR's research on mathematical tasks and experiences with teachers and teacher educators. Presents examples of task analysis and issues that teachers should reflect on. (ASK)

  13. Test Takers' Writing Activities during the "TOEFL iBT"® Writing Tasks: A Stimulated Recall Study. "TOEFL iBT"® Research Report. TOEFL iBT-25. ETS Research Report No. RR-15-04

    ERIC Educational Resources Information Center

    Barkaoui, Khaled

    2015-01-01

    This study aimed to describe the writing activities that test takers engage in when responding to the writing tasks in the "TOEFL iBT"[superscript R] test and to examine the effects of task type and test-taker English language proficiency (ELP) and keyboarding skills on the frequency and distribution of these activities. Each of 22 test…

  14. Activities of the Oil Implementation Task Force, reporting period March--August 1991; Contracts for field projects and supporting research on enhanced oil recovery, reporting period October--December 1990

    SciTech Connect

    Not Available

    1991-10-01

    Activities of DOE's Oil Implementation Task Force for the period March--August 1991 are reviewed. Contracts for fields projects and supporting research on enhanced oil recovery are discussed, with a list of related publications given. Enhanced recovery processes covered include chemical flooding, gas displacement, thermal recovery, and microbial recovery.

  15. Task Analysis of Shuttle Entry and Landing Activities

    NASA Technical Reports Server (NTRS)

    Holland, Albert W.; Vanderark, Stephen T.

    1993-01-01

    The Task Analysis of Shuttle Entry and Landing (E/L) Activities documents all tasks required to land the Orbiter following an STS mission. In addition to analysis of tasks performed, task conditions are described, including estimated time for completion, altitude, relative velocity, normal and lateral acceleration, location of controls operated or monitored, and level of g's experienced. This analysis precedes further investigations into potential effects of zero g on piloting capabilities for landing the Orbiter following long-duration missions. This includes, but is not limited to, researching the effects of extended duration missions on piloting capabilities. Four primary constraints of the analysis must be clarified: (1) the analysis depicts E/L in a static manner--the actual process is dynamic; (2) the task analysis was limited to a paper analysis, since it was not feasible to conduct research in the actual setting (i.e., observing or filming duration an actual E/L); (3) the tasks included are those required for E/L during nominal, daylight conditions; and (4) certain E/L tasks will vary according to the flying style of each commander.

  16. Physical Activity Perceptions of Task- and Ego-Oriented Children

    ERIC Educational Resources Information Center

    Cruickshanks, Carla M.

    2010-01-01

    Children begin to show sedentary behaviors around the age of 12 and increased mortality is associated with sedentary behaviors in children and adults. This case study examined physical activity (PA) perceptions of task oriented and ego oriented children. Research has addressed perceptions based on goal orientations and how perception of PA changes…

  17. Brain activities during synchronized tapping task.

    PubMed

    Hiroyasu, Tomoyuki; Murakami, Akiho; Mao Gto; Yokouchi, Hisatake

    2015-01-01

    This study aims to investigate how people process information about other people to determine a response during human-to-human cooperative work. As a preliminary study, the mechanism of cooperative work was examined using interaction between a machine and a human. This machine was designed to have an "other person" model that simulates an emotional model of another person. The task performed in the experiment was a synchronized tapping task. Two models were prepared for this experiment, a simple model that does not employ the other person model and a synchronized model that employs the other person model. Subjects performed cooperative work with these machines. During the experiment, brain activities were measured using functional near-infrared spectroscopy. It was observed that the left inferior frontal gyrus was activated more with the synchronized model than the simple model. PMID:26737670

  18. Task-dependent posterior cingulate activation in mild cognitive impairment

    PubMed Central

    Ries, Michele L.; Schmitz, Taylor W.; Kawahara-Baccus, Tisha N.; Torgerson, Britta M.; Trivedi, Mehul A.; Johnson, Sterling C.

    2009-01-01

    Neuroimaging research has demonstrated that the posterior cingulate cortex (PCC) is functionally compromised in individuals diagnosed with amnestic Mild Cognitive Impairment (MCI), a major risk factor for the development of Alzheimer’s disease (AD). In functional magnetic resonance imaging (fMRI) studies with healthy participants, this same region is active during self-appraisal (requiring retrieval of semantic knowledge about the self) as well as episodic recognition of recently-learned information. Administering both types of tasks to people with MCI may reveal important information regarding the role of the PCC in recollection. This study investigated fMRI activation in the PCC in individuals with MCI and age, gender, and education-matched controls across two tasks. The first task was a visual episodic recognition task in which participants indicated whether pictures had or had not been presented during a study session. The second task was an autobiographical self-appraisal task in which subjects rated themselves on a set of trait adjectives. Results of a conjunction analysis revealed the PCC as the sole region commonly active during both tasks in the healthy older adults. Furthermore, additional analysis revealed an interaction in the PCC indicating a task-dependent response in the MCI group. MCI participants showed PCC activation during self-appraisal, but not during episodic retrieval. These results suggest in MCI that the PCC shows functional degradation during episodic retrieval of visual information learned in the laboratory. In contrast, the PCC’s role in retrieval and evaluation of highly-elaborated information regarding the self is more well-preserved. PMID:16102979

  19. Research Activities.

    ERIC Educational Resources Information Center

    Santa Fe Community Coll., Gainesville, FL.

    The five parts of this report are: research on instruction; faculty dissertations; inter-institutional research; in-college research; and college-endorsed research. The first covers experiments in teaching French, practical nursing, English, math, and chemistry, and in giving examinations. Faculty dissertations include studies of post-graduate…

  20. Activities of the Oil Implementation Task Force; Contracts for field projects and supporting research on enhanced oil recovery, July--September 1990

    SciTech Connect

    Tiedemann, H.A. )

    1991-05-01

    The report contains a general introduction and background to DOE's revised National Energy Strategy Advanced Oil Recovery Program and activities of the Oil Implementation Task Force; a detailed synopsis of the symposium, including technical presentations, comments and suggestions; a section of technical information on deltaic reservoirs; and appendices containing a comprehensive listing of references keyed to general deltaic and geological aspects of reservoirs and those relevant to six selected deltaic plays. Enhanced recovery processes include chemical floodings, gas displacement, thermal recovery, geoscience, and microbial recovery.

  1. Task Force Examines U.S. Hurricane Research Agenda

    NASA Astrophysics Data System (ADS)

    Zielinski, Sarah

    2006-01-01

    While U.S. federal, state, and local governments continue to debate what should be done, following the devastating 2005 hurricane season, to rebuild the Gulf Coast and to prevent future disasters, a task force of the U.S. National Science Board (NSB) has begun an effort to construct a national agenda for federally-sponsored hurricane research. At a 24 January meeting at the U.S. National Science Foundation (NSF) headquarters in Arlington,Va., task force members and government representatives examined current hurricane-related research conducted and supported by several federal agencies, identified gaps in understanding and future priorities, and discussed how these agencies can better coordinate their activities.

  2. Task-free MRI predicts individual differences in brain activity during task performance.

    PubMed

    Tavor, I; Parker Jones, O; Mars, R B; Smith, S M; Behrens, T E; Jbabdi, S

    2016-04-01

    When asked to perform the same task, different individuals exhibit markedly different patterns of brain activity. This variability is often attributed to volatile factors, such as task strategy or compliance. We propose that individual differences in brain responses are, to a large degree, inherent to the brain and can be predicted from task-independent measurements collected at rest. Using a large set of task conditions, spanning several behavioral domains, we train a simple model that relates task-independent measurements to task activity and evaluate the model by predicting task activation maps for unseen subjects using magnetic resonance imaging. Our model can accurately predict individual differences in brain activity and highlights a coupling between brain connectivity and function that can be captured at the level of individual subjects. PMID:27124457

  3. Task-free MRI predicts individual differences in brain activity during task performance.

    PubMed

    Tavor, I; Parker Jones, O; Mars, R B; Smith, S M; Behrens, T E; Jbabdi, S

    2016-04-01

    When asked to perform the same task, different individuals exhibit markedly different patterns of brain activity. This variability is often attributed to volatile factors, such as task strategy or compliance. We propose that individual differences in brain responses are, to a large degree, inherent to the brain and can be predicted from task-independent measurements collected at rest. Using a large set of task conditions, spanning several behavioral domains, we train a simple model that relates task-independent measurements to task activity and evaluate the model by predicting task activation maps for unseen subjects using magnetic resonance imaging. Our model can accurately predict individual differences in brain activity and highlights a coupling between brain connectivity and function that can be captured at the level of individual subjects.

  4. Flexible task-specific control using active vision

    NASA Astrophysics Data System (ADS)

    Firby, Robert J.; Swain, Michael J.

    1992-04-01

    This paper is about the interface between continuous and discrete robot control. We advocate encapsulating continuous actions and their related sensing strategies into behaviors called situation specific activities, which can be constructed by a symbolic reactive planner. Task- specific, real-time perception is a fundamental part of these activities. While researchers have successfully used primitive touch and sonar sensors in such situations, it is more problematic to achieve reasonable performance with complex signals such as those from a video camera. Active vision routines are suggested as a means of incorporating visual data into real time control and as one mechanism for designating aspects of the world in an indexical-functional manner. Active vision routines are a particularly flexible sensing methodology because different routines extract different functional attributes from the world using the same sensor. In fact, there will often be different active vision routines for extracting the same functional attribute using different processing techniques. This allows an agent substantial leeway to instantiate its activities in different ways under different circumstances using different active vision routines. We demonstrate the utility of this architecture with an object tracking example. A control system is presented that can be reconfigured by a reactive planner to achieve different tasks. We show how this system allows us to build interchangeable tracking activities that use either color histogram or motion based active vision routines.

  5. Task Descriptions in Diagnostic Radiology. Research Report No. 7. Volume 1, Medical Tasks: What the Radiologist Does.

    ERIC Educational Resources Information Center

    Gilpatrick, Eleanor

    The first of four volumes in Research Report No. 7 of the Health Services Mobility Study (HSMS), this book contains 143 task descriptions covering most of the medical activities carried out by diagnostic radiologists. (The work carried out by radiologic technologists, and administrative, machine-related, and nursing-type functions are found in…

  6. Anterior Medial Prefrontal Cortex Exhibits Activation during Task Preparation but Deactivation during Task Execution

    PubMed Central

    Koshino, Hideya; Minamoto, Takehiro; Ikeda, Takashi; Osaka, Mariko; Otsuka, Yuki; Osaka, Naoyuki

    2011-01-01

    Background The anterior prefrontal cortex (PFC) exhibits activation during some cognitive tasks, including episodic memory, reasoning, attention, multitasking, task sets, decision making, mentalizing, and processing of self-referenced information. However, the medial part of anterior PFC is part of the default mode network (DMN), which shows deactivation during various goal-directed cognitive tasks compared to a resting baseline. One possible factor for this pattern is that activity in the anterior medial PFC (MPFC) is affected by dynamic allocation of attentional resources depending on task demands. We investigated this possibility using an event related fMRI with a face working memory task. Methodology/Principal Findings Sixteen students participated in a single fMRI session. They were asked to form a task set to remember the faces (Face memory condition) or to ignore them (No face memory condition), then they were given 6 seconds of preparation period before the onset of the face stimuli. During this 6-second period, four single digits were presented one at a time at the center of the display, and participants were asked to add them and to remember the final answer. When participants formed a task set to remember faces, the anterior MPFC exhibited activation during a task preparation period but deactivation during a task execution period within a single trial. Conclusions/Significance The results suggest that the anterior MPFC plays a role in task set formation but is not involved in execution of the face working memory task. Therefore, when attentional resources are allocated to other brain regions during task execution, the anterior MPFC shows deactivation. The results suggest that activation and deactivation in the anterior MPFC are affected by dynamic allocation of processing resources across different phases of processing. PMID:21829668

  7. Active microwave remote sensing research program plan. Recommendations of the Earth Resources Synthetic Aperture Radar Task Force. [application areas: vegetation canopies, surface water, surface morphology, rocks and soils, and man-made structures

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A research program plan developed by the Office of Space and Terrestrial Applications to provide guidelines for a concentrated effort to improve the understanding of the measurement capabilities of active microwave imaging sensors, and to define the role of such sensors in future Earth observations programs is outlined. The focus of the planned activities is on renewable and non-renewable resources. Five general application areas are addressed: (1) vegetation canopies, (2) surface water, (3) surface morphology, (4) rocks and soils, and (5) man-made structures. Research tasks are described which, when accomplished, will clearly establish the measurement capabilities in each area, and provide the theoretical and empirical results needed to specify and justify satellite systems using imaging radar sensors for global observations.

  8. Suggested drilling research tasks for the Federal Government

    SciTech Connect

    Carson, C.C.

    1984-04-01

    A brief summary discussion of drilling, drilling research and the role of the government in drilling research is presented. Specific research and development areas recommended for federal consideration are listed. The technical nature of the identified tasks is emphasized. The Appendices present the factual basis for the discussion and recommendations. Numerous references are noted in the Appendices.

  9. Device research task (processing and high-efficiency solar cells)

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This task has been expanded since the last 25th Project Integration Meeting (PIM) to include process research in addition to device research. The objective of this task is to assist the Flat-plate Solar Array (FSA) Project in meeting its near- and long-term goals by identifying and implementing research in the areas of device physics, device structures, measurement techniques, material-device interactions, and cell processing. The research efforts of this task are described and reflect the deversity of device research being conducted. All of the contracts being reported are either completed or near completion and culminate the device research efforts of the FSA Project. Optimazation methods and silicon solar cell numerical models, carrier transport and recombination parameters in heavily doped silicon, development and analysis of silicon solar cells of near 20% efficiency, and SiN sub x passivation of silicon surfaces are discussed.

  10. Task Descriptions in Diagnostic Radiology. Research Report No. 7. Volume 4, Index of Tasks by Code Number and Extended Name.

    ERIC Educational Resources Information Center

    Gilpatrick, Eleanor

    The fourth of four volumes in Research Report No. 7 of the Health Services Mobility Study (HSMS), this book contains the extended task names of all the tasks whose descriptions can be found in the three prior volumes. It serves as an index to all the tasks by listing the volume in which each task description appears. Chapter 1 of this volume…

  11. Gender Issues in Addictions Research: The Report of the Task Group on Gender-Focused Research.

    ERIC Educational Resources Information Center

    Addiction Research Foundation, Toronto (Ontario).

    The Task Group on Gender-Focused Research was established to raise awareness and interest in gender as a variable in addictions research at the Addiction Research Foundation (ARF) in Ontario (Canada). Recognizing that much of the research on substance abuse has focused on males, the Task Group was charged with providing a basis for the development…

  12. Task complexity modulates pilot electroencephalographic activity during real flights.

    PubMed

    Di Stasi, Leandro L; Diaz-Piedra, Carolina; Suárez, Juan; McCamy, Michael B; Martinez-Conde, Susana; Roca-Dorda, Joaquín; Catena, Andrés

    2015-07-01

    Most research connecting task performance and neural activity to date has been conducted in laboratory conditions. Thus, field studies remain scarce, especially in extreme conditions such as during real flights. Here, we investigated the effects of flight procedures of varied complexity on the in-flight EEG activity of military helicopter pilots. Flight procedural complexity modulated the EEG power spectrum: highly demanding procedures (i.e., takeoff and landing) were associated with higher EEG power in the higher frequency bands, whereas less demanding procedures (i.e., flight exercises) were associated with lower EEG power over the same frequency bands. These results suggest that EEG recordings may help to evaluate an operator's cognitive performance in challenging real-life scenarios, and thus could aid in the prevention of catastrophic events. PMID:25728307

  13. Evidence of Conjoint Activation of the Anterior Insular and Cingulate Cortices during Effortful Tasks.

    PubMed

    Engström, Maria; Karlsson, Thomas; Landtblom, Anne-Marie; Craig, A D Bud

    2014-01-01

    The ability to perform effortful tasks is a topic that has received considerable interest in the research of higher functions of the human brain. Neuroimaging studies show that the anterior insular and the anterior cingulate cortices are involved in a multitude of cognitive tasks that require mental effort. In this study, we investigated brain responses to effort using cognitive tasks with task-difficulty modulations and functional magnetic resonance imaging (fMRI). We hypothesized that effortful performance involves modulation of activation in the anterior insular and the anterior cingulate cortices, and that the modulation correlates with individual performance levels. Healthy participants performed tasks probing verbal working memory capacity using the reading span task, and visual perception speed using the inspection time task. In the fMRI analysis, we focused on identifying effort-related brain activation. The results showed that working memory and inspection time performances were directly related. The bilateral anterior insular and anterior cingulate cortices showed significantly increased activation during each task with common portions that were active across both tasks. We observed increased brain activation in the right anterior insula and the anterior cingulate cortex in participants with low working memory performance. In line with the reported results, we suggest that activation in the anterior insular and cingulate cortices is consistent with the neural efficiency hypothesis (Neubauer).

  14. Prefrontal activation during two Japanese Stroop tasks revealed with multi-channel near-infrared spectroscopy.

    PubMed

    Watanabe, Yukina; Sumitani, Satsuki; Hosokawa, Mai; Ohmori, Tetsuro

    2015-01-01

    The Stroop task is sometimes used in psychiatric research to elicit prefrontal activity, which presumably reflects cognitive functioning. Although there are two Stroop tasks (Kana script and Kanji script) in Japan, it is unclear whether these tasks elicit the same hemoglobin changes. Moreover, it is unclear whether psychological conditions or characteristics influence hemoglobin changes in the Japanese Stroop task. The aim of this study was to clarify whether hemoglobin changes elicited by the two Japanese Stroop tasks accurately reflected cognitive functioning. Hemoglobin changes were measured with multi-channel near-infrared spectroscopy (NIRS) in 100 healthy Japanese participants performing two Japanese Stroop tasks. The Beck-Depression Inventory (BDI), State-Trait-Anxiety Inventory (STAI), and Maudsley Obsessive Compulsive Inventory (MOCI) were administered to participants to identify psychological conditions or personality characteristics. Compared with the Kanji task, the Kana task produced a greater Stroop effect and a larger increase in oxyhemoglobin (oxy-Hb) concentration. Moreover there were no significant correlations between oxy-Hb concentration and BDI, STAI-trait, STAI-state, or MOCI scores. Therefore we found that a participant's psychological conditions or characteristics did not influence the hemodynamic changes during either task. These data suggest the Kana Stroop task is more useful than the Kanji Stroop task for NIRS studies in psychiatric research.

  15. Task Templates Based on Misconception Research. CSE Report 646.

    ERIC Educational Resources Information Center

    Cromley, Jennifer G.; Mislevy, Robert J.

    2004-01-01

    Researchers spend much time and effort developing measures, including measures of students? conceptual knowledge. In an effort to make such assessments easier to design, the Principled Assessment Designs for Inquiry (PADI) project has developed a framework for designing tasks and to illustrate that its use has ?reverse engineered? several …

  16. Modulation of human motoneuron activity by a mental arithmetic task.

    PubMed

    Bensoussan, Laurent; Duclos, Yann; Rossi-Durand, Christiane

    2012-10-01

    This study aimed to determine whether the performance of a mental task affects motoneuron activity. To this end, the tonic discharge pattern of wrist extensor motor units was analyzed in healthy subjects while they were required to maintain a steady wrist extension force and to concurrently perform a mental arithmetic (MA) task. A shortening of the mean inter-spike interval (ISI) and a decrease in ISI variability occurred when MA task was superimposed to the motor task. Aloud and silent MA affected equally the rate and variability of motoneuron discharge. Increases in surface EMG activity and force level were consistent with the modulation of the motor unit discharge rate. Trial-by-trial analysis of the characteristics of motor unit firing revealed that performing MA increases activation of wrist extensor SMU. It is suggested that increase in muscle spindle afferent activity, resulting from fusimotor drive activation by MA, may have contributed to the increase in synaptic inputs to motoneurons during the mental task performance, likely together with enhancement in the descending drive. The finding that a mental task affects motoneuron activity could have consequences in assessment of motor disabilities and in rehabilitation in motor pathologies.

  17. Task-Related, Low-Frequency Task-Residual, and Resting State Activity in the Default Mode Network Brain Regions

    PubMed Central

    Zhang, Sheng; Li, Chiang-Shan R.

    2012-01-01

    The hypothesis of a default mode network (DMN) of brain function is based on observations of task-independent decreases of brain activity during effort as participants are engaged in tasks in contrast to resting. On the other hand, studies also showed that DMN regions activate rather than deactivate in response to task-related events. Thus, does DMN “deactivate” during effort as compared to resting? We hypothesized that, with high-frequency event-related signals removed, the task-residual activities of the DMN would decrease as compared to resting. We addressed this hypothesis with two approaches. First, we examined DMN activities during resting, task residuals, and task conditions in the stop signal task using independent component analysis (ICA). Second, we compared the fractional amplitude of low-frequency fluctuation (fALFF) signals of DMN in resting, task residuals, and task data. In the results of ICA of 76 subjects, the precuneus and posterior cingulate cortex (PCC) showed increased activation during task as compared to resting and task residuals, indicating DMN responses to task events. Precuneus but not the PCC showed decreased activity during task residual as compared to resting. The latter finding was mirrored by fALFF, which is decreased in the precuneus during task residuals, as compared to resting and task. These results suggested that the low-frequency blood oxygen level-dependent signals of the precuneus may represent a useful index of effort during cognitive performance. PMID:22661964

  18. United States Research and Development effort on ITER magnet tasks

    DOE PAGES

    Martovetsky, Nicolai N.; Reierson, Wayne T.

    2011-01-22

    This study presents the status of research and development (R&D) magnet tasks that are being performed in support of the U.S. ITER Project Office (USIPO) commitment to provide a central solenoid assembly and toroidal field conductor for the ITER machine to be constructed in Cadarache, France. The following development tasks are presented: winding development, inlets and outlets development, internal and bus joints development and testing, insulation development and qualification, vacuum-pressure impregnation, bus supports, and intermodule structure and materials characterization.

  19. PFC Activity Pattern During Verbal WM Task in Healthy Male and Female Subjects: A NIRS Study.

    PubMed

    Gao, Chenyang; Zhang, Lei; Luo, Dewu; Liu, Dan; Gong, Hui

    2016-01-01

    Near-infrared spectroscopy (NIRS), as a non-invasive optical imaging method, has been widely used in psychology research. Working memory (WM) is an extensively researched psychological concept related to the temporary storage and processing of information. Many neuropsychological studies demonstrate that several brain areas of prefrontal cortex (PFC) are engaged during verbal WM tasks. The gender-based differences in WM remains under dispute. To better understand the active module and gender differences in PFC activity patterns during verbal WM tasks, we investigated the blood oxygenation changes of the PFC in 15 healthy subjects using a homemade multichannel continuous-wave NIRS instrument, while performing a verbal n-back task. We employed traditional activation and novel connectivity analyses simultaneously. Males had a higher level of oxygenation activity and connectivity in PFC than females. Only the results of females revealed a leftward lateralization in the 2-back task. PMID:27526142

  20. Units of analysis in task-analytic research.

    PubMed

    Haring, T G; Kennedy, C H

    1988-01-01

    We develop and discuss four criteria for evaluating the appropriateness of units of analysis for task-analytic research and suggest potential alternatives to the units of analysis currently used. Of the six solutions discussed, the most commonly used unit of analysis in current behavior analytic work, percentage correct, meets only one of the four criteria. Five alternative units of analysis are presented and evaluated: (a) percentage of opportunities to perform meeting criterion, (b) trials to criteria, (c) cumulative competent performances, (d) percentage correct with competent performance coded, and (e) percentage correct with competent performance coded and a grid showing performance on individual steps of the task analysis. Of the solutions evaluated, only one--percentage correct with competent performance coded and a task analysis grid--met all four criteria.

  1. [Literature and schizophrenia. Research trends and research tasks].

    PubMed

    Kudszus, W G

    1979-01-01

    Research on schizophrenia and on the psychopathology of creativity is increasingly absorbing and transforming insights from literature (Büchner, Celan, Kafka, Proust) and literary aesthetics. This development is discussed against the background of the history of psychiatric research. Regarding contemporary research trends, special emphasis is placed on communication theory as presented by the Palo Alto group (double bind theory), anti-psychiatry (Cooper, Laing), French structuralism (Foucault, Lacan), and on schizoanalysis (Deleuze and Guattari). Traditional concepts of mental health and illness are called into question. PMID:387336

  2. MAT - MULTI-ATTRIBUTE TASK BATTERY FOR HUMAN OPERATOR WORKLOAD AND STRATEGIC BEHAVIOR RESEARCH

    NASA Technical Reports Server (NTRS)

    Comstock, J. R.

    1994-01-01

    MAT, a Multi-Attribute Task battery, gives the researcher the capability of performing multi-task workload and performance experiments. The battery provides a benchmark set of tasks for use in a wide range of laboratory studies of operator performance and workload. MAT incorporates tasks analogous to activities that aircraft crew members perform in flight, while providing a high degree of experiment control, performance data on each subtask, and freedom to use non-pilot test subjects. The MAT battery primary display is composed of four separate task windows which are as follows: a monitoring task window which includes gauges and warning lights, a tracking task window for the demands of manual control, a communication task window to simulate air traffic control communications, and a resource management task window which permits maintaining target levels on a fuel management task. In addition, a scheduling task window gives the researcher information about future task demands. The battery also provides the option of manual or automated control of tasks. The task generates performance data for each subtask. The task battery may be paused and onscreen workload rating scales presented to the subject. The MAT battery was designed to use a serially linked second computer to generate the voice messages for the Communications task. The MATREMX program and support files, which are included in the MAT package, were designed to work with the Heath Voice Card (Model HV-2000, available through the Heath Company, Benton Harbor, Michigan 49022); however, the MATREMX program and support files may easily be modified to work with other voice synthesizer or digitizer cards. The MAT battery task computer may also be used independent of the voice computer if no computer synthesized voice messages are desired or if some other method of presenting auditory messages is devised. MAT is written in QuickBasic and assembly language for IBM PC series and compatible computers running MS-DOS. The

  3. Area Reports. Advanced materials and devices research area. Silicon materials research task, and advanced silicon sheet task

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The objectives of the Silicon Materials Task and the Advanced Silicon Sheet Task are to identify the critical technical barriers to low-cost silicon purification and sheet growth that must be overcome to produce a PV cell substrate material at a price consistent with Flat-plate Solar Array (FSA) Project objectives and to overcome these barriers by performing and supporting appropriate R&D. Progress reports are given on silicon refinement using silane, a chemical vapor transport process for purifying metallurgical grade silicon, silicon particle growth research, and modeling of silane pyrolysis in fluidized-bed reactors.

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

    PubMed Central

    Sakimoto, Yuya; Sakata, Shogo

    2014-01-01

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

  5. Incentive value, unclear task difficulty, and cardiovascular reactivity in active coping.

    PubMed

    Richter, Michael; Gendolla, Guido H E

    2007-03-01

    An experiment with 44 participants assessed the moderating effects of four levels of incentive value on cardiovascular responses in active coping. Randomly assigned to one of four different incentive conditions, participants performed a memory task without knowing its difficulty in advance. By means of successfully performing the task participants could either win no reward, 10 Swiss Francs, 20 Swiss Francs, or 30 Swiss Francs. In accordance with the theoretical predictions derived from motivational intensity theory, reactivity of systolic blood pressure and heart rate monotonically increased with incentive value. Thereby, these findings provide additional empirical evidence for the predictions of motivational intensity theory with regard to unclear task difficulty and extend recent research (Richter, M., Gendolla, G.H.E., 2006. Incentive effects on cardiovascular reactivity in active coping with unclear task difficulty. Int. J. Psychophysiol. 61, 216-225.), which was not conclusive regarding the predicted monotonic relationship between incentive value and cardiovascular reactivity under conditions of unclear task difficulty.

  6. Wind power forecasting: IEA Wind Task 36 & future research issues

    NASA Astrophysics Data System (ADS)

    Giebel, G.; Cline, J.; Frank, H.; Shaw, W.; Pinson, P.; Hodge, B.-M.; Kariniotakis, G.; Madsen, J.; Möhrlen, C.

    2016-09-01

    This paper presents the new International Energy Agency Wind Task 36 on Forecasting, and invites to collaborate within the group. Wind power forecasts have been used operatively for over 20 years. Despite this fact, there are still several possibilities to improve the forecasts, both from the weather prediction side and from the usage of the forecasts. The new International Energy Agency (IEA) Task on Forecasting for Wind Energy tries to organise international collaboration, among national meteorological centres with an interest and/or large projects on wind forecast improvements (NOAA, DWD, MetOffice, met.no, DMI,...), operational forecaster and forecast users. The Task is divided in three work packages: Firstly, a collaboration on the improvement of the scientific basis for the wind predictions themselves. This includes numerical weather prediction model physics, but also widely distributed information on accessible datasets. Secondly, we will be aiming at an international pre-standard (an IEA Recommended Practice) on benchmarking and comparing wind power forecasts, including probabilistic forecasts. This WP will also organise benchmarks, in cooperation with the IEA Task WakeBench. Thirdly, we will be engaging end users aiming at dissemination of the best practice in the usage of wind power predictions. As first results, an overview of current issues for research in short-term forecasting of wind power is presented.

  7. Spontaneous and task-evoked brain activity negatively interact

    PubMed Central

    He, Biyu J.

    2013-01-01

    A widely held assumption is that spontaneous and task-evoked brain activity sum linearly, such that the recorded brain response in each single trial is the algebraic sum of the constantly changing ongoing activity and the stereotypical evoked activity. Using functional magnetic resonance imaging (fMRI) signals acquired from normal humans, we show that this assumption is invalid. Across widespread cortices, evoked activity interacts negatively with ongoing activity, such that higher prestimulus baseline results in less activation or more deactivation. As a consequence of this negative interaction, trial-to-trial variability of cortical activity decreases following stimulus onset. We further show that variability reduction follows overlapping but distinct spatial pattern from that of task activation/deactivation and it contains behaviorally relevant information. These results favor an alternative perspective to the traditional dichotomous framework of ongoing and evoked activity – one that views the brain as a nonlinear dynamical system whose trajectory is tighter when performing a task; further, incoming sensory stimuli modulate the brain’s activity in a manner that depends on its initial state. We propose that across-trial variability may provide a new approach to brain mapping in the context of cognitive experiments. PMID:23486941

  8. Formal Derivation of Lotka-Volterra-Haken Amplitude Equations of Task-Related Brain Activity in Multiple, Consecutively Performed Tasks

    NASA Astrophysics Data System (ADS)

    Frank, T. D.

    The Lotka-Volterra-Haken equations have been frequently used in ecology and pattern formation. Recently, the equations have been proposed by several research groups as amplitude equations for task-related patterns of brain activity. In this theoretical study, the focus is on the circular causality aspect of pattern formation systems as formulated within the framework of synergetics. Accordingly, the stable modes of a pattern formation system inhibit the unstable modes, whereas the unstable modes excite the stable modes. Using this circular causality principle it is shown that under certain conditions the Lotka-Volterra-Haken amplitude equations can be derived from a general model of brain activity akin to the Wilson-Cowan model. The model captures the amplitude dynamics for brain activity patterns in experiments involving several consecutively performed multiple-choice tasks. This is explicitly demonstrated for two-choice tasks involving grasping and walking. A comment on the relevance of the theoretical framework for clinical psychology and schizophrenia is given as well.

  9. Task Lists for Health Occupations. Radiologic Aide. Activity Aide. Optometric Assistant. Physical Therapy Aide. Education for Employment Task Lists.

    ERIC Educational Resources Information Center

    Lathrop, Janice

    These task lists contain employability skills and tasks for the following health occupations: radiologic aide, activity aide, physical therapy aide, and optometric assistant. The duties and tasks found in these lists form the basis of instructional content for secondary, postsecondary, and adult occupational training programs. Employability skills…

  10. Job level risk assessment using task level ACGIH hand activity level TLV scores: a pilot study.

    PubMed

    Drinkaus, Phillip; Sesek, Richard; Bloswick, Donald S; Mann, Clay; Bernard, Thomas

    2005-01-01

    Existing upper extremity musculoskeletal disorder analytical tools are primarily intended for single or mono-task jobs. However, many jobs contain more than 1 task and some include job rotation. This case/control study investigates methods of modifying an existing tool, the American Conference of Governmental Industrial Hygienists (ACGIH) Hand Activity Level (HAL) Threshold Limit Value (TLV), to assess the upper extremity risk of multi-task jobs. Various methods of combining the task differences and ratios into a job level assessment were explored. Two methods returned significant odds ratios, (p < .05) of 18.0 (95% CI 1.8-172) and 12.0 (95% CI 1.2-120). These results indicate that a modified ACGIH HAL TLV may provide insight into the work-related risk of multi-task jobs. Further research is needed to optimize this process. PMID:16219155

  11. Absorbed in the task: Personality measures predict engagement during task performance as tracked by error negativity and asymmetrical frontal activity.

    PubMed

    Tops, Mattie; Boksem, Maarten A S

    2010-12-01

    We hypothesized that interactions between traits and context predict task engagement, as measured by the amplitude of the error-related negativity (ERN), performance, and relative frontal activity asymmetry (RFA). In Study 1, we found that drive for reward, absorption, and constraint independently predicted self-reported persistence. We hypothesized that, during a prolonged monotonous task, absorption would predict initial ERN amplitudes, constraint would delay declines in ERN amplitudes and deterioration of performance, and drive for reward would predict left RFA when a reward could be obtained. Study 2, employing EEG recordings, confirmed our predictions. The results showed that most traits that have in previous research been related to ERN amplitudes have a relationship with the motivational trait persistence in common. In addition, trait-context combinations that are likely associated with increased engagement predict larger ERN amplitudes and RFA. Together, these results support the hypothesis that engagement may be a common underlying factor predicting ERN amplitude.

  12. ICA model order selection of task co-activation networks

    PubMed Central

    Ray, Kimberly L.; McKay, D. Reese; Fox, Peter M.; Riedel, Michael C.; Uecker, Angela M.; Beckmann, Christian F.; Smith, Stephen M.; Fox, Peter T.; Laird, Angela R.

    2013-01-01

    Independent component analysis (ICA) has become a widely used method for extracting functional networks in the brain during rest and task. Historically, preferred ICA dimensionality has widely varied within the neuroimaging community, but typically varies between 20 and 100 components. This can be problematic when comparing results across multiple studies because of the impact ICA dimensionality has on the topology of its resultant components. Recent studies have demonstrated that ICA can be applied to peak activation coordinates archived in a large neuroimaging database (i.e., BrainMap Database) to yield whole-brain task-based co-activation networks. A strength of applying ICA to BrainMap data is that the vast amount of metadata in BrainMap can be used to quantitatively assess tasks and cognitive processes contributing to each component. In this study, we investigated the effect of model order on the distribution of functional properties across networks as a method for identifying the most informative decompositions of BrainMap-based ICA components. Our findings suggest dimensionality of 20 for low model order ICA to examine large-scale brain networks, and dimensionality of 70 to provide insight into how large-scale networks fractionate into sub-networks. We also provide a functional and organizational assessment of visual, motor, emotion, and interoceptive task co-activation networks as they fractionate from low to high model-orders. PMID:24339802

  13. Effects of overhead work configuration on muscle activity during a simulated drilling task.

    PubMed

    Maciukiewicz, Jacquelyn M; Cudlip, Alan C; Chopp-Hurley, Jaclyn N; Dickerson, Clark R

    2016-03-01

    Overhead work is a known catalyst for occupational shoulder injury. Industrial workers must often adopt awkward overhead postures and loading profiles to complete required tasks, potentially elevating injury risk. This research examined the combined influence of multiple overhead working parameters on upper extremity muscular demands for an industrial drilling application. Twenty-two right-handed males completed 24 unilateral and bilateral overhead work exertions stratified by direction (upward, forward), point of force application (15, 30 and 45 cm in front of the body), and whole-body posture (seated, standing). The dependency of electromyographic (EMG) activity on several factors was established. Significant two-way interactions existed between point of force application and direction (p < 0.0001) and direction and whole body posture (p < 0.0001). An average increase in muscular activity of 6.5% maximal voluntary contraction (MVC) occurred for the contralateral limb when the bilateral task was completed, compared to unilateral tasks, with less than a 1% MVC increase for the active limb. These findings assist evidence-based approaches to overhead tasks, specifically in the construction industry. A bilateral task configuration is recommended to reduce glenohumeral stability demands. As well, particularly for tasks with a far reach distance, design tasks to promote a forward directed exertion. The considerable inter-subject variability suggests that fixed heights are not ideal, and should be avoided, and where this is not possible reaches should be reduced. PMID:26674399

  14. Analysis of Time-Dependent Brain Network on Active and MI Tasks for Chronic Stroke Patients

    PubMed Central

    Chang, Won Hyuk; Kim, Yun-Hee; Lee, Seong-Whan; Kwon, Gyu Hyun

    2015-01-01

    Several researchers have analyzed brain activities by investigating brain networks. However, there is a lack of the research on the temporal characteristics of the brain network during a stroke by EEG and the comparative studies between motor execution and imagery, which became known to have similar motor functions and pathways. In this study, we proposed the possibility of temporal characteristics on the brain networks of a stroke. We analyzed the temporal properties of the brain networks for nine chronic stroke patients by the active and motor imagery tasks by EEG. High beta band has a specific role in the brain network during motor tasks. In the high beta band, for the active task, there were significant characteristics of centrality and small-worldness on bilateral primary motor cortices at the initial motor execution. The degree centrality significantly increased on the contralateral primary motor cortex, and local efficiency increased on the ipsilateral primary motor cortex. These results indicate that the ipsilateral primary motor cortex constructed a powerful subnetwork by influencing the linked channels as compensatory effect, although the contralateral primary motor cortex organized an inefficient network by using the connected channels due to lesions. For the MI task, degree centrality and local efficiency significantly decreased on the somatosensory area at the initial motor imagery. Then, there were significant correlations between the properties of brain networks and motor function on the contralateral primary motor cortex and somatosensory area for each motor execution/imagery task. Our results represented that the active and MI tasks have different mechanisms of motor acts. Based on these results, we indicated the possibility of customized rehabilitation according to different motor tasks. We expect these results to help in the construction of the customized rehabilitation system depending on motor tasks by understanding temporal functional

  15. Is Neural Activity Detected by ERP-Based Brain-Computer Interfaces Task Specific?

    PubMed Central

    Wenzel, Markus A.; Almeida, Inês; Blankertz, Benjamin

    2016-01-01

    Objective Brain-computer interfaces (BCIs) that are based on event-related potentials (ERPs) can estimate to which stimulus a user pays particular attention. In typical BCIs, the user silently counts the selected stimulus (which is repeatedly presented among other stimuli) in order to focus the attention. The stimulus of interest is then inferred from the electroencephalogram (EEG). Detecting attention allocation implicitly could be also beneficial for human-computer interaction (HCI), because it would allow software to adapt to the user’s interest. However, a counting task would be inappropriate for the envisaged implicit application in HCI. Therefore, the question was addressed if the detectable neural activity is specific for silent counting, or if it can be evoked also by other tasks that direct the attention to certain stimuli. Approach Thirteen people performed a silent counting, an arithmetic and a memory task. The tasks required the subjects to pay particular attention to target stimuli of a random color. The stimulus presentation was the same in all three tasks, which allowed a direct comparison of the experimental conditions. Results Classifiers that were trained to detect the targets in one task, according to patterns present in the EEG signal, could detect targets in all other tasks (irrespective of some task-related differences in the EEG). Significance The neural activity detected by the classifiers is not strictly task specific but can be generalized over tasks and is presumably a result of the attention allocation or of the augmented workload. The results may hold promise for the transfer of classification algorithms from BCI research to implicit relevance detection in HCI. PMID:27792781

  16. The temporal dynamics of metacognition: Dissociating task-related activity from later metacognitive processes.

    PubMed

    Desender, Kobe; Van Opstal, Filip; Hughes, Gethin; Van den Bussche, Eva

    2016-02-01

    In recent years, neuroscience research spent much effort in revealing brain activity related to metacognition. Despite this endeavor, it remains unclear exactly when metacognitive experiences develop during task performance. To investigate this, the current study used EEG to temporally and spatially dissociate task-related activity from metacognitive activity. In a masked priming paradigm, metacognitive experiences of difficulty were induced by manipulating congruency between prime and target. As expected, participants more frequently rated incongruent trials as difficult and congruent trials as easy, while being completely unable to perceive the masked primes. Results showed that both the N2 and the P3 ERP components were modulated by congruency, but that only the P3 modulation interacted with metacognitive experiences. Single-trial analysis additionally showed that the magnitude of the P3 modulation by congruency accurately predicted the metacognitive response. Source localization indicated that the N2 task-related activity originated in the ACC, whereas the P3-interplay between task-related activation and metacognitive experiences originated from the precuneus. We conclude that task-related activity can be dissociated from later metacognitive processing.

  17. Academic Users' Information Searching on Research Topics: Characteristics of Research Tasks and Search Strategies

    ERIC Educational Resources Information Center

    Du, Jia Tina; Evans, Nina

    2011-01-01

    This project investigated how academic users search for information on their real-life research tasks. This article presents the findings of the first of two studies. The study data were collected in the Queensland University of Technology (QUT) in Brisbane, Australia. Eleven PhD students' searching behaviors on personal research topics were…

  18. Research on Mathematics Teachers as Partners in Task Design

    ERIC Educational Resources Information Center

    Jones, Keith; Pepin, Birgit

    2016-01-01

    Mathematical tasks and tools, including tasks in the form of digital tools, are key resources in mathematics teaching and in mathematics teacher education. Even so, the "design" of mathematical tasks is perceived in different ways: sometimes seen as something distinct from the teaching and learning process, and sometimes as integral to…

  19. Response Activation in Overlapping Tasks and the Response-Selection Bottleneck

    ERIC Educational Resources Information Center

    Schubert, Torsten; Fischer, Rico; Stelzel, Christine

    2008-01-01

    The authors investigated the impact of response activation on dual-task performance by presenting a subliminal prime before the stimulus in Task 2 (S2) of a psychological refractory period (PRP) task. Congruence between prime and S2 modulated the reaction times in Task 2 at short stimulus onset asynchrony despite a PRP effect. This Task 2…

  20. Brain Activation of Identity Switching in Multiple Identity Tracking Task.

    PubMed

    Lyu, Chuang; Hu, Siyuan; Wei, Liuqing; Zhang, Xuemin; Talhelm, Thomas

    2015-01-01

    When different objects switch identities in the multiple identity tracking (MIT) task, viewers need to rebind objects' identity and location, which requires attention. This rebinding helps people identify the regions targets are in (where they need to focus their attention) and inhibit unimportant regions (where distractors are). This study investigated the processing of attentional tracking after identity switching in an adapted MIT task. This experiment used three identity-switching conditions: a target-switching condition (where the target objects switched identities), a distractor-switching condition (where the distractor objects switched identities), and a no-switching condition. Compared to the distractor-switching condition, the target-switching condition elicited greater activation in the frontal eye fields (FEF), intraparietal sulcus (IPS), and visual cortex. Compared to the no-switching condition, the target-switching condition elicited greater activation in the FEF, inferior frontal gyrus (pars orbitalis) (IFG-Orb), IPS, visual cortex, middle temporal lobule, and anterior cingulate cortex. Finally, the distractor-switching condition showed greater activation in the IFG-Orb compared to the no-switching condition. These results suggest that, in the target-switching condition, the FEF and IPS (the dorsal attention network) might be involved in goal-driven attention to targets during attentional tracking. In addition, in the distractor-switching condition, the activation of the IFG-Orb may indicate salient change that pulls attention away automatically.

  1. Complexity, Accuracy, Fluency and Lexis in Task-Based Performance: A Synthesis of the Ealing Research

    ERIC Educational Resources Information Center

    Skehan, Peter; Foster, Pauline

    2012-01-01

    This chapter will present a research synthesis of a series of studies, termed here the Ealing research. The studies use the same general framework to conceptualise tasks and task performance, enabling easier comparability. The different studies, although each is self-contained, build into a wider picture of task performance. The major point of…

  2. The effect of task-oriented training on the muscle activation of the upper extremity in chronic stroke patients

    PubMed Central

    Park, JuHyung

    2016-01-01

    [Purpose] The aim of this study was to determine the effects of task-oriented training on upper extremity muscle activation in daily activities performed by chronic stoke patients. [Subjects and Methods] In this research, task-oriented training was conducted by 2 chronic hemiplegic stroke patients. Task-oriented training was conducted 5 times a week, 30 minutes per day, for 2 weeks. Evaluation was conducted 3 times before and after the intervention. The Change of muscle activation in the upper extremity was measured using a BTS FreeEMG 300. [Results] The subjects’ root mean square values for agonistic muscles for the reaching activity increased after the intervention. All subjects’ co-coordination ratios decreased after the intervention in all movements of reaching activity. [Conclusion] Through this research, task-oriented training was proven to be effective in improving the muscle activation of the upper extremity in chronic hemiplegic stroke patients. PMID:27190488

  3. The effect of task-oriented training on the muscle activation of the upper extremity in chronic stroke patients.

    PubMed

    Park, JuHyung

    2016-04-01

    [Purpose] The aim of this study was to determine the effects of task-oriented training on upper extremity muscle activation in daily activities performed by chronic stoke patients. [Subjects and Methods] In this research, task-oriented training was conducted by 2 chronic hemiplegic stroke patients. Task-oriented training was conducted 5 times a week, 30 minutes per day, for 2 weeks. Evaluation was conducted 3 times before and after the intervention. The Change of muscle activation in the upper extremity was measured using a BTS FreeEMG 300. [Results] The subjects' root mean square values for agonistic muscles for the reaching activity increased after the intervention. All subjects' co-coordination ratios decreased after the intervention in all movements of reaching activity. [Conclusion] Through this research, task-oriented training was proven to be effective in improving the muscle activation of the upper extremity in chronic hemiplegic stroke patients. PMID:27190488

  4. Trends in problem-solving research - Twelve recently described tasks.

    NASA Technical Reports Server (NTRS)

    Coates, G. D.; Alluisi, E. A.; Morgan, B. B., Jr.

    1971-01-01

    Review of descriptions of the 12 problem-solving tasks developed since the last review (Ray, 1955) of this topic, indicating that the newer tasks are more sophisticated in design and provide for better experimental control than those used prior to 1953. Validity, reliability, sensitivity, trainability, problem structure, and problem difficulty are discussed as criteria for the selection of tasks to be used in studies of skilled problem-solving performance.

  5. JV Task 119 - Effects of Aging on Treated Activated Carbons

    SciTech Connect

    Edwin Olson; Lucinda Hamre; John Pavlish; Blaise Mibeck

    2009-03-25

    For both the United States and Canada, testing has been under way for electric utilities to find viable and economical mercury control strategies to meet pending future mercury emission limits. The technology that holds the most promise for mercury control in low-chlorine lignite to meet the needs of the Clean Air Act in the United States and the Canada-Wide Standards in Canada is injection of treated activated carbon (AC) into the flue gas stream. Most of the treated carbons are reported to be halogenated, often with bromine. Under a previous multiyear project headed by the Energy & Environmental Research Center (EERC), testing was performed on a slipstream unit using actual lignite-derived flue gas to evaluate various sorbent technologies for their effectiveness, performance, and cost. Testing under this project showed that halogenated ACs performed very well, with mercury capture rates often {ge} 90%. However, differences were noted between treated ACs with respect to reactivity and capacity, possibly as a result of storage conditions. Under certain conditions (primarily storage in ambient air), notable performance degradation had occurred in mercury capture efficiency. Therefore, a small exploratory task within this project evaluated possible differences resulting from storage conditions and subsequent effects of aging that might somehow alter their chemical or physical properties. In order to further investigate this potential degradation of treated (halogenated) ACs, the EERC, together with DOE's National Energy Technology Laboratory, the North Dakota Industrial Commission (NDIC), the Electric Power Research Institute (EPRI), SaskPower, and Otter Tail Power Company, assessed the aging effects of brominated ACs for the effect that different storage durations, temperatures, and humidity conditions have on the mercury sorption capacity of treated ACs. No aging effects on initial capture activity were observed for any carbons or conditions in the investigation

  6. Management Skills. Skills Task Force Research Paper 3.

    ERIC Educational Resources Information Center

    Johnson, Steven; Winterton, Jonathan

    A task force was convened to identify the nature, extent, and pattern of skill needs and shortages for managerial occupations in the United Kingdom (UK). The task force began by examining the key challenges facing managers in the UK. The following factors were among those considered: economic policies promoting liberalization and deregulation;…

  7. Scientific Merit Review of Directed Research Tasks Within the NASA Human Research Program

    NASA Technical Reports Server (NTRS)

    Charles, John B.

    2010-01-01

    The Human Research Program is instrumental in developing and delivering research findings, health countermeasures, and human systems technologies for spacecraft. :HRP is subdivided into 6 research entities, or Elements. Each Element is charged with providing the Program with knowledge and capabilities to conduct research to address the human health and performance risks as well as advance the readiness levels of technology and countermeasures. Project: An Element may be further subdivided into Projects, which are defined as an integrated set of tasks undertaken to deliver a product or set of products

  8. International Reference Ionosphere (IRI): Task Force Activity 2000

    NASA Technical Reports Server (NTRS)

    Bilitza, D.

    2000-01-01

    The annual IRI Task Force Activity was held at the Abdus Salam International Center for Theoretical Physics in Trieste, Italy from July 10 to July 14. The participants included J. Adeniyi (University of Ilorin, Nigeria), D. Bilitza (NSSDC/RITSS, USA), D. Buresova (Institute of Atmospheric Physics, Czech Republic), B. Forte (ICTP, Italy), R. Leitinger (University of Graz, Austria), B. Nava (ICTP, Italy), M. Mosert (University National Tucuman, Argentina), S. Pulinets (IZMIRAN, Russia), S. Radicella (ICTP, Italy), and B. Reinisch (University of Mass. Lowell, USA). The main topic of this Task Force Activity was the modeling of the topside ionosphere and the development of strategies for modeling of ionospheric variability. Each day during the workshop week the team debated a specific modeling problem in the morning during informal presentations and round table discussions of all participants. Ways of resolving the specific modeling problem were devised and tested in the afternoon in front of the computers of the ICTP Aeronomy and Radiopropagation Laboratory using ICTP s computer networks and internet access.

  9. Learning to research in first grade: Bridging the transition from narrative to expository texts and tasks

    NASA Astrophysics Data System (ADS)

    Weise, Richard

    Decades of research indicate that students at all academic grade and performance levels perform poorly with informational texts and tasks and particularly with locating assignment-relevant information in expository texts. Students have little understanding of the individual tasks required, the arc of the activity, the hierarchical structure of the information they seek, or how to reconstitute and interpret the information they extract. Poor performance begins with the introduction of textbooks and research assignments in fourth grade and continues into adulthood. However, to date, neither educators nor researchers have substantially addressed this problem. In this quasi-experimental study, we ask if first-grade children can perform essential tasks in identifying, extracting, and integrating assignment-relevant information and if instruction improves their performance. To answer this question, we conducted a 15-week, teacher-led, intervention in two first-grade classrooms in an inner-city Nashville elementary school. We created a computer learning environment (NoteTaker) to facilitate children's creation of a mental model of the research process and a narrative/expository bridge curriculum to support the children's transition from all narrative to all expository texts and tasks. We also created a new scaffolding taxonomy and a reading-to-research model to focus our research. Teachers participated in weekly professional development workshops. The results of this quasi-experimental study indicate that at-risk, first-grade children are able to (a) identify relevant information in an expository text, (b) categorize the information they identify, and (c) justify their choice of category. Children's performance in the first and last tasks significantly improved with instruction, and low-performing readers showed the greatest benefits from instruction. We find that the children's performance in categorizing information depended upon content-specific knowledge that was not

  10. Meditation leads to reduced default mode network activity beyond an active task

    PubMed Central

    Garrison, Kathleen A.; Zeffiro, Thomas A.; Scheinost, Dustin; Constable, R. Todd; Brewer, Judson A.

    2015-01-01

    Meditation has been associated with relatively reduced activity in the default mode network, a brain network implicated in self-related thinking and mind wandering. However, previous imaging studies have typically compared meditation to rest despite other studies reporting differences in brain activation patterns between meditators and controls at rest. Moreover, rest is associated with a range of brain activation patterns across individuals that has only recently begun to be better characterized. Therefore, this study compared meditation to another active cognitive task, both to replicate findings that meditation is associated with relatively reduced default mode network activity, and to extend these findings by testing whether default mode activity was reduced during meditation beyond the typical reductions observed during effortful tasks. In addition, prior studies have used small groups, whereas the current study tested these hypotheses in a larger group. Results indicate that meditation is associated with reduced activations in the default mode network relative to an active task in meditators compared to controls. Regions of the default mode showing a group by task interaction include the posterior cingulate/precuneus and anterior cingulate cortex. These findings replicate and extend prior work indicating that suppression of default mode processing may represent a central neural process in long-term meditation, and suggest that meditation leads to relatively reduced default mode processing beyond that observed during another active cognitive task. PMID:25904238

  11. Meditation leads to reduced default mode network activity beyond an active task.

    PubMed

    Garrison, Kathleen A; Zeffiro, Thomas A; Scheinost, Dustin; Constable, R Todd; Brewer, Judson A

    2015-09-01

    Meditation has been associated with relatively reduced activity in the default mode network, a brain network implicated in self-related thinking and mind wandering. However, previous imaging studies have typically compared meditation to rest, despite other studies having reported differences in brain activation patterns between meditators and controls at rest. Moreover, rest is associated with a range of brain activation patterns across individuals that has only recently begun to be better characterized. Therefore, in this study we compared meditation to another active cognitive task, both to replicate the findings that meditation is associated with relatively reduced default mode network activity and to extend these findings by testing whether default mode activity was reduced during meditation, beyond the typical reductions observed during effortful tasks. In addition, prior studies had used small groups, whereas in the present study we tested these hypotheses in a larger group. The results indicated that meditation is associated with reduced activations in the default mode network, relative to an active task, for meditators as compared to controls. Regions of the default mode network showing a Group × Task interaction included the posterior cingulate/precuneus and anterior cingulate cortex. These findings replicate and extend prior work indicating that the suppression of default mode processing may represent a central neural process in long-term meditation, and they suggest that meditation leads to relatively reduced default mode processing beyond that observed during another active cognitive task.

  12. Tasks of research in forensic medicine - different study types in clinical research and forensic medicine.

    PubMed

    Madea, Burkhard; Saukko, Pekka; Musshoff, Frank

    2007-01-17

    In the last years the research output of forensic medicine has sometimes been regarded as insufficient and as of poor quality, especially when parameters as impact factors and external funding were taken into account. However, forensic medicine has different tasks compared to clinical medicine. The main difference between basic subjects, clinical and forensic medicine is not a lack of scientific efficiency in forensic medicine but is a result of the questions asked, the available methods and specific aims. In contrast to natural-scientific research, forensic science has furthermore important intersections with arts and socio-scientific disciplines. Etiologic and pathogenetic research is of only limited relevance in forensic medicine. Thus, forensic medicine is excluded from these research fields, which are mainly supported by external funding. In forensic medicine research mainly means applied research regarding findings, the probative value and reconstruction as well as examination at different points of intersection between medicine and law. Clinical types of research such as controlled randomised, prospective cross-sectional, cohort or case-control studies can only rarely be applied in forensic medicine due to the area specific research fields (e.g. thantatology, violent death, vitality, traffic medicine, analytical toxicology, hemogenetics and stain analysis). The types of studies which are successfully established in forensic medicine are comparison of methods, sensitivity studies, validation of methods, kinetic examinations etc. Tasks of research in forensic medicine and study types, which may be applied will be addressed.

  13. The Scintillation Prediction Observations Research Task (SPORT) Mission

    NASA Astrophysics Data System (ADS)

    Spann, James; Swenson, Charles; Durão, Otavio; Loures, Luis; Heelis, Rod; Bishop, Rebecca; Le, Guan; Abdu, Mangalathayil; Krause, Linda; Nardin, Clezio; Fonseca, Eloi

    2016-04-01

    Structure in the charged particle number density in the equatorial ionosphere can have a profound impact on the fidelity of HF, VHF and UHF radio signals that are used for ground-to-ground and space-to-ground communication and navigation. The degree to which such systems can be compromised depends in large part on the spatial distribution of the structured regions in the ionosphere and the background plasma density in which they are embedded. In order to address these challenges it is necessary to accurately distinguish the background ionospheric conditions that favor the generation of irregularities from those that do not. Additionally we must relate the evolution of those conditions to the subsequent evolution of the irregular plasma regions themselves. The background ionospheric conditions are conveniently described by latitudinal profiles of the plasma density at nearly constant altitude, which describe the effects of ExB drifts and neutral winds, while the appearance and growth of plasma structure requires committed observations from the ground from at least one fixed longitude. This talk will present an international collaborative CubeSat mission called SPORT that stands for the Scintillation Prediction Observations Research Task. This mission will advance our understanding of the nature and evolution of ionospheric structures around sunset to improve predictions of disturbances that affect radio propagation and telecommunication signals. The science goals will be accomplished by a unique combination of satellite observations from a nearly circular middle inclination orbit and the extensive operation of ground based observations from South America near the magnetic equator. This approach promises Explorer class science at a CubeSat price.

  14. The Scintillation Prediction Observations Research Task (SPORT) Mission

    NASA Astrophysics Data System (ADS)

    Spann, J. F.; Swenson, C.; Durão, O.; Loures, L.; Heelis, R. A.; Bishop, R. L.; Le, G.; Abdu, M. A.; Habash Krause, L.; De Nardin, C. M.; Fonseca, E.

    2015-12-01

    Structure in the charged particle number density in the equatorial ionosphere can have a profound impact on the fidelity of HF, VHF and UHF radio signals that are used for ground-to-ground and space-to-ground communication and navigation. The degree to which such systems can be compromised depends in large part on the spatial distribution of the structured regions in the ionosphere and the background plasma density in which they are embedded. In order to address these challenges it is necessary to accurately distinguish the background ionospheric conditions that favor the generation of irregularities from those that do not. Additionally we must relate the evolution of those conditions to the subsequent evolution of the irregular plasma regions themselves. The background ionospheric conditions are conveniently described by latitudinal profiles of the plasma density at nearly constant altitude, which describe the effects of ExB drifts and neutral winds, while the appearance and growth of plasma structure requires committed observations from the ground from at least one fixed longitude. This talk will present an international collaborative CubeSat mission called SPORT that stands for Scintillation Prediction Observations Research Task. This mission that will advance our understanding of the nature and evolution of ionospheric structures around sunset to improve predictions of disturbances that affect radio propagation and telecommunication signals. The science goals will be accomplished by a unique combination of satellite observations from a nearly circular middle inclination orbit and the extensive operation of ground based observations from South America near the magnetic equator. This approach promises Explorer class science at a CubeSat price.

  15. The Scintillation Prediction Observations Research Task (SPORT) Mission

    NASA Astrophysics Data System (ADS)

    Spann, James; Le, Guan; Swenson, Charles; Denardini, Clezio Marcos; Bishop, Rebecca L.; Abdu, Mangalathayil A.; Cupertino Durao, Otavio S.; Heelis, Roderick; Loures, Luis; Krause, Linda; Fonseca, Eloi

    2016-07-01

    Structure in the charged particle number density in the equatorial ionosphere can have a profound impact on the fidelity of HF, VHF and UHF radio signals that are used for ground-to-ground and space-to-ground communication and navigation. The degree to which such systems can be compromised depends in large part on the spatial distribution of the structured regions in the ionosphere and the background plasma density in which they are embedded. In order to address these challenges it is necessary to accurately distinguish the background ionospheric conditions that favor the generation of irregularities from those that do not. Additionally we must relate the evolution of those conditions to the subsequent evolution of the irregular plasma regions themselves. The background ionospheric conditions are conveniently described by latitudinal profiles of the plasma density at nearly constant altitude, which describe the effects of ExB drifts and neutral winds, while the appearance and growth of plasma structure requires committed observations from the ground from at least one fixed longitude. This talk will present an international collaborative CubeSat mission called SPORT that stands for the Scintillation Prediction Observations Research Task. This mission will advance our understanding of the nature and evolution of ionospheric structures around sunset to improve predictions of disturbances that affect radio propagation and telecommunication signals. The science goals will be accomplished by a unique combination of satellite observations from a nearly circular middle inclination orbit and the extensive operation of ground based observations from South America near the magnetic equator. This approach promises Explorer class science at a CubeSat price.

  16. Active vision task and postural control in healthy, young adults: Synergy and probably not duality.

    PubMed

    Bonnet, Cédrick T; Baudry, Stéphane

    2016-07-01

    In upright stance, individuals sway continuously and the sway pattern in dual tasks (e.g., a cognitive task performed in upright stance) differs significantly from that observed during the control quiet stance task. The cognitive approach has generated models (limited attentional resources, U-shaped nonlinear interaction) to explain such patterns based on competitive sharing of attentional resources. The objective of the current manuscript was to review these cognitive models in the specific context of visual tasks involving gaze shifts toward precise targets (here called active vision tasks). The selection excluded the effects of early and late stages of life or disease, external perturbations, active vision tasks requiring head and body motions and the combination of two tasks performed together (e.g., a visual task in addition to a computation in one's head). The selection included studies performed by healthy, young adults with control and active - difficult - vision tasks. Over 174 studies found in Pubmed and Mendeley databases, nine were selected. In these studies, young adults exhibited significantly lower amplitude of body displacement (center of pressure and/or body marker) under active vision tasks than under the control task. Furthermore, the more difficult the active vision tasks were, the better the postural control was. This underscores that postural control during active vision tasks may rely on synergistic relations between the postural and visual systems rather than on competitive or dual relations. In contrast, in the control task, there would not be any synergistic or competitive relations.

  17. Summary of Chernobyl followup research activities

    SciTech Connect

    Not Available

    1992-06-01

    In NUREG-1251, ``Implications of the Accident at Chernobyl for Safety Regulation of Commercial Nuclear Power Plants in the United States,`` April 1989, the NRC staff concluded that no immediate changes in NRC`s regulations regarding design or operation of US commercial reactors were needed; however, it recommended that certain issues be considered further. NRC`s Chernobyl followup research program consisted of the research tasks undertaken in response to the recommendations in NUREG-1251. It included 23 tasks that addressed potential lessons to be learned from the Chernobyl accident. This report presents summaries of NRC`s Chernobyl followup research tasks. For each task, the Chernobyl-related issues are indicated, the work is described, and the staff`s findings and conclusions are presented. More detailed reports concerning the work are referenced where applicable. This report closes out NRC`s Chernobyl followup research program as such, but additional research will be conducted on some issues as needed. The report includes remarks concerning significant further activity with respect to the issues addressed.

  18. Summary of Chernobyl followup research activities

    SciTech Connect

    Not Available

    1992-06-01

    In NUREG-1251, Implications of the Accident at Chernobyl for Safety Regulation of Commercial Nuclear Power Plants in the United States,'' April 1989, the NRC staff concluded that no immediate changes in NRC's regulations regarding design or operation of US commercial reactors were needed; however, it recommended that certain issues be considered further. NRC's Chernobyl followup research program consisted of the research tasks undertaken in response to the recommendations in NUREG-1251. It included 23 tasks that addressed potential lessons to be learned from the Chernobyl accident. This report presents summaries of NRC's Chernobyl followup research tasks. For each task, the Chernobyl-related issues are indicated, the work is described, and the staff's findings and conclusions are presented. More detailed reports concerning the work are referenced where applicable. This report closes out NRC's Chernobyl followup research program as such, but additional research will be conducted on some issues as needed. The report includes remarks concerning significant further activity with respect to the issues addressed.

  19. Solar Energy Research and Education Foundation. Final reports by task

    SciTech Connect

    von Reis, K.; Waegel, A.S.; Totten, M.

    1997-12-10

    This document contains final reports for the following tasks: kiosk for the children`s museum renewable energy exhibit and display, internet promotional and educational material, Aurora renewable energy science and engineering, CD-ROM training materials, presentations and traveling display, radio show `Energy Matters`, and newspaper articles and weekly news column.

  20. Characterizing “fibrofog”: Subjective appraisal, objective performance, and task-related brain activity during a working memory task

    PubMed Central

    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

  1. Reliability of negative BOLD in ipsilateral sensorimotor areas during unimanual task activity.

    PubMed

    McGregor, Keith M; Sudhyadhom, Atchar; Nocera, Joe; Seff, Ari; Crosson, Bruce; Butler, Andrew J

    2015-06-01

    Research using functional magnetic resonance imaging has for numerous years now reported the existence of a negative blood oxygenation level dependent (BOLD) response. Based on accumulating evidence, this negative BOLD signal appears to represent an active inhibition of cortical areas in which it is found during task activity. This particularly important with respect to motor function given that it is fairly well-established that, in younger adults, the ipsilateral sensorimotor cortex exhibits negative BOLD during unimanual movements in fMRI. This interhemispheric suppression of cortical activity may have useful implications for our understanding of both basic motor function and rehabilitation of injury or disease. However, to date, we are aware of no study that has tested the reliability of evoked negative BOLD in ipsilateral sensorimotor cortex in individuals across sessions. The current study employs a unimanual finger opposition task previously shown to evoke negative BOLD in ipsilateral sensorimotor cortex across three sessions. Reliability metrics across sessions indicates that both the magnitude and location of ipsilateral sensorimotor negative BOLD response is relatively stable over each of the three sessions. Moreover, the volume of negative BOLD in ipsilateral cortex was highly correlated with volume of positive BOLD activity in the contralateral primary motor cortex. These findings show that the negative BOLD signal can be reliably evoked in unimanual task paradigms, and that the signal dynamic could represent an active suppression of the ipsilateral sensorimotor cortex originating from the contralateral motor areas.

  2. A Study of Student Consultants' Comfort Levels with Research-Related Tasks

    ERIC Educational Resources Information Center

    Holler Phillips, Carissa M.

    2011-01-01

    Student consulting is a form of problem-based learning through which students work on strategic issues for organizations. To explore how students perceive their research-related tasks, 15 student consultants were asked to evaluate their comfort levels with seven tasks--adapted from the Association of College and Research Libraries' Information…

  3. Transient Decline in Hippocampal Theta Activity during the Acquisition Process of the Negative Patterning Task

    PubMed Central

    Sakimoto, Yuya; Okada, Kana; Takeda, Kozue; Sakata, Shogo

    2013-01-01

    Hippocampal function is important in the acquisition of negative patterning but not of simple discrimination. This study examined rat hippocampal theta activity during the acquisition stages (early, middle, and late) of the negative patterning task (A+, B+, AB-). The results showed that hippocampal theta activity began to decline transiently (for 500 ms after non-reinforced stimulus presentation) during the late stage of learning in the negative patterning task. In addition, this transient decline in hippocampal theta activity in the late stage was lower in the negative patterning task than in the simple discrimination task. This transient decline during the late stage of task acquisition may be related to a learning process distinctive of the negative patterning task but not the simple discrimination task. We propose that the transient decline of hippocampal theta activity reflects inhibitory learning and/or response inhibition after the presentation of a compound stimulus specific to the negative patterning task. PMID:23936249

  4. Compare harvest systems. Minnesota Agripower Project, Task II research report

    SciTech Connect

    Wilcke, W.F.; Hietala, J.S.

    1997-10-30

    Our primary objectives for this task were to determine field performance and harvest losses for several types of cutting and baling equipment and to compare these values with those found in the literature. Originally, we had planned to study use of preservatives and their effect on harvest and storage losses, but since the MNVAP processing plant is not currently buying hay treated with preservatives, we did minimal work with preservatives during this phase of the project.

  5. Alzheimer Disease Alters the Relationship of Cardiorespiratory Fitness With Brain Activity During the Stroop Task

    PubMed Central

    Gayed, Matthew R.; Honea, Robyn A.; Savage, Cary R.; Hobbs, Derek; Burns, Jeffrey M.

    2013-01-01

    Background Despite mounting evidence that physical activity has positive benefits for brain and cognitive health, there has been little characterization of the relationship between cardiorespiratory (CR) fitness and cognition-associated brain activity as measured by functional magnetic resonance imaging (fMRI). The lack of evidence is particularly glaring for diseases such as Alzheimer disease (AD) that degrade cognitive and functional performance. Objective The aim of this study was to describe the relationship between regional brain activity during cognitive tasks and CR fitness level in people with and without AD. Design A case-control, single-observation study design was used. Methods Thirty-four individuals (18 without dementia and 16 in the earliest stages of AD) completed maximal exercise testing and performed a Stroop task during fMRI. Results Cardiorespiratory fitness was inversely associated with anterior cingulate activity in the participants without dementia (r=−.48, P=.05) and unassociated with activation in those with AD (P>.7). Weak associations of CR fitness and middle frontal cortex were noted. Limitations The wide age range and the use of a single task in fMRI rather than multiple tasks challenging different cognitive capacities were limitations of the study. Conclusions The results offer further support of the relationship between CR fitness and regional brain activity. However, this relationship may be attenuated by disease. Future work in this area may provide clinicians and researchers with interpretable and dependable regional fMRI biomarker signatures responsive to exercise intervention. It also may shed light on mechanisms by which exercise can support cognitive function. PMID:23559521

  6. Using Fiberless, Wearable fNIRS to Monitor Brain Activity in Real-world Cognitive Tasks

    PubMed Central

    Pinti, Paola; Aichelburg, Clarisse; Lind, Frida; Power, Sarah; Swingler, Elizabeth; Merla, Arcangelo; Hamilton, Antonia; Gilbert, Sam; Burgess, Paul; Tachtsidis, Ilias

    2015-01-01

    Functional Near Infrared Spectroscopy (fNIRS) is a neuroimaging technique that uses near-infrared light to monitor brain activity. Based on neurovascular coupling, fNIRS is able to measure the haemoglobin concentration changes secondary to neuronal activity. Compared to other neuroimaging techniques, fNIRS represents a good compromise in terms of spatial and temporal resolution. Moreover, it is portable, lightweight, less sensitive to motion artifacts and does not impose significant physical restraints. It is therefore appropriate to monitor a wide range of cognitive tasks (e.g., auditory, gait analysis, social interaction) and different age populations (e.g., new-borns, adults, elderly people). The recent development of fiberless fNIRS devices has opened the way to new applications in neuroscience research. This represents a unique opportunity to study functional activity during real-world tests, which can be more sensitive and accurate in assessing cognitive function and dysfunction than lab-based tests. This study explored the use of fiberless fNIRS to monitor brain activity during a real-world prospective memory task. This protocol is performed outside the lab and brain haemoglobin concentration changes are continuously measured over the prefrontal cortex while the subject walks around in order to accomplish several different tasks. PMID:26651025

  7. JV Task 90 - Activated Carbon Production from North Dakota Lignite

    SciTech Connect

    Steven Benson; Charlene Crocker; Rokan Zaman; Mark Musich; Edwin Olson

    2008-03-31

    The Energy & Environmental Research Center (EERC) has pursued a research program for producing activated carbon from North Dakota lignite that can be competitive with commercial-grade activated carbon. As part of this effort, small-scale production of activated carbon was produced from Fort Union lignite. A conceptual design of a commercial activated carbon production plant was drawn, and a market assessment was performed to determine likely revenue streams for the produced carbon. Activated carbon was produced from lignite coal in both laboratory-scale fixed-bed reactors and in a small pilot-scale rotary kiln. The EERC was successfully able to upgrade the laboratory-scale activated carbon production system to a pilot-scale rotary kiln system. The activated carbon produced from North Dakota lignite was superior to commercial grade DARCO{reg_sign} FGD and Rheinbraun's HOK activated coke product with respect to iodine number. The iodine number of North Dakota lignite-derived activated carbon was between 600 and 800 mg I{sub 2}/g, whereas the iodine number of DARCO FGD was between 500 and 600 mg I{sub 2}/g, and the iodine number of Rheinbraun's HOK activated coke product was around 275 mg I{sub 2}/g. The EERC performed both bench-scale and pilot-scale mercury capture tests using the activated carbon made under various optimization process conditions. For comparison, the mercury capture capability of commercial DARCO FGD was also tested. The lab-scale apparatus is a thin fixed-bed mercury-screening system, which has been used by the EERC for many mercury capture screen tests. The pilot-scale systems included two combustion units, both equipped with an electrostatic precipitator (ESP). Activated carbons were also tested in a slipstream baghouse at a Texas power plant. The results indicated that the activated carbon produced from North Dakota lignite coal is capable of removing mercury from flue gas. The tests showed that activated carbon with the greatest iodine number

  8. Functional Activation during the Rapid Visual Information Processing Task in a Middle Aged Cohort: An fMRI Study.

    PubMed

    Neale, Chris; Johnston, Patrick; Hughes, Matthew; Scholey, Andrew

    2015-01-01

    The Rapid Visual Information Processing (RVIP) task, a serial discrimination task where task performance believed to reflect sustained attention capabilities, is widely used in behavioural research and increasingly in neuroimaging studies. To date, functional neuroimaging research into the RVIP has been undertaken using block analyses, reflecting the sustained processing involved in the task, but not necessarily the transient processes associated with individual trial performance. Furthermore, this research has been limited to young cohorts. This study assessed the behavioural and functional magnetic resonance imaging (fMRI) outcomes of the RVIP task using both block and event-related analyses in a healthy middle aged cohort (mean age = 53.56 years, n = 16). The results show that the version of the RVIP used here is sensitive to changes in attentional demand processes with participants achieving a 43% accuracy hit rate in the experimental task compared with 96% accuracy in the control task. As shown by previous research, the block analysis revealed an increase in activation in a network of frontal, parietal, occipital and cerebellar regions. The event related analysis showed a similar network of activation, seemingly omitting regions involved in the processing of the task (as shown in the block analysis), such as occipital areas and the thalamus, providing an indication of a network of regions involved in correct trial performance. Frontal (superior and inferior frontal gryi), parietal (precuenus, inferior parietal lobe) and cerebellar regions were shown to be active in both the block and event-related analyses, suggesting their importance in sustained attention/vigilance. These networks and the differences between them are discussed in detail, as well as implications for future research in middle aged cohorts. PMID:26488289

  9. Functional Activation during the Rapid Visual Information Processing Task in a Middle Aged Cohort: An fMRI Study

    PubMed Central

    Neale, Chris; Johnston, Patrick; Hughes, Matthew; Scholey, Andrew

    2015-01-01

    The Rapid Visual Information Processing (RVIP) task, a serial discrimination task where task performance believed to reflect sustained attention capabilities, is widely used in behavioural research and increasingly in neuroimaging studies. To date, functional neuroimaging research into the RVIP has been undertaken using block analyses, reflecting the sustained processing involved in the task, but not necessarily the transient processes associated with individual trial performance. Furthermore, this research has been limited to young cohorts. This study assessed the behavioural and functional magnetic resonance imaging (fMRI) outcomes of the RVIP task using both block and event-related analyses in a healthy middle aged cohort (mean age = 53.56 years, n = 16). The results show that the version of the RVIP used here is sensitive to changes in attentional demand processes with participants achieving a 43% accuracy hit rate in the experimental task compared with 96% accuracy in the control task. As shown by previous research, the block analysis revealed an increase in activation in a network of frontal, parietal, occipital and cerebellar regions. The event related analysis showed a similar network of activation, seemingly omitting regions involved in the processing of the task (as shown in the block analysis), such as occipital areas and the thalamus, providing an indication of a network of regions involved in correct trial performance. Frontal (superior and inferior frontal gryi), parietal (precuenus, inferior parietal lobe) and cerebellar regions were shown to be active in both the block and event-related analyses, suggesting their importance in sustained attention/vigilance. These networks and the differences between them are discussed in detail, as well as implications for future research in middle aged cohorts. PMID:26488289

  10. Reaction time-related activity reflecting periodic, task-specific cognitive control.

    PubMed

    Barber, Anita D; Pekar, James J; Mostofsky, Stewart H

    2016-01-01

    Reaction time (RT) is associated with increased amplitude of the Blood Oxygen-Level Dependent (BOLD) response in cognitive control regions. The current study examined whether the Primary Condition (PC) effect and RT-BOLD effect both reflect the same cognitive control processes. In addition, RT-BOLD effects were examined in two Go/No-go tasks with different demands to determine whether RT-related activity is task-dependent, reflecting the recruitment of task-specific cognitive processes. Data simulations showed that RT-related activity could be distinguished from that of the primary condition if it is mean-centered. In that case, RT-related activity reflects periodically-engaged processes rather than "time-on-task" (ToT). RT-related activity was mostly distinct from that of the primary Go contrast, particularly for the perceptual decision task. Therefore, RT effects can reflect additional cognitive processes that are not captured by the PC contrast consistent with a periodic-engagement account. RT-BOLD effects occurred in a separate set of regions for the two tasks. For the task requiring a perceptual decision, RT-related activity occurred within occipital and posterior parietal regions supporting visual attention. For the task requiring a working memory decision, RT-related activity occurred within fronto-parietal regions supporting the maintenance and retrieval of task representations. The findings suggest that RT-related activity reflects task-specific processes that are periodically-engaged, particularly during less demanding tasks. PMID:26318935

  11. Planning and Conducting Research Activities.

    ERIC Educational Resources Information Center

    Christiansen, Richard L.

    1983-01-01

    Some directions and influences on dental research activities in the near future are discussed. Current challenges include international competition, fellowships, and equipment. Potential research activity includes preventive medicine, epidemiology, chronic illness, the elderly, bioengineering, materials research, nutrition, soft tissue research,…

  12. Reduction of Dual-task Costs by Noninvasive Modulation of Prefrontal Activity in Healthy Elders

    PubMed Central

    Manor, Brad; Zhou, Junhong; Jor'dan, Azizah; Zhang, Jue; Fang, Jing; Pascual-Leone, Alvaro

    2016-01-01

    Dual tasking (e.g., walking or standing while performing a cognitive task) disrupts performance in one or both tasks, and such dual-task costs increase with aging into senescence. Dual tasking activates a network of brain regions including pFC. We therefore hypothesized that facilitation of prefrontal cortical activity via transcranial direct current stimulation (tDCS) would reduce dual-task costs in older adults. Thirty-seven healthy older adults completed two visits during which dual tasking was assessed before and after 20 min of real or sham tDCS targeting the left pFC. Trials of single-task standing, walking, and verbalized serial subtractions were completed, along with dual-task trials of standing or walking while performing serial subtractions. Dual-task costs were calculated as the percent change in markers of gait and postural control and serial subtraction performance, from single to dual tasking. Significant dual-task costs to standing, walking, and serial subtraction performance were observed before tDCS (p < .01). These dual-task costs were less after real tDCS as compared with sham tDCS as well as compared with either pre-tDCS condition (p < .03). Further analyses indicated that tDCS did not alter single task performance but instead improved performance solely within dual-task conditions (p < .02). These results demonstrate that dual tasking can be improved by modulating prefrontal activity, thus indicating that dual-task decrements are modifiable and may not necessarily reflect an obligatory consequence of aging. Moreover, tDCS may ultimately serve as a novel approach to preserving dual-task capacity into senescence. PMID:26488591

  13. Hippocampal theta wave activity during configural and non-configural tasks in rats.

    PubMed

    Sakimoto, Yuya; Hattori, Minoru; Takeda, Kozue; Okada, Kana; Sakata, Shogo

    2013-03-01

    This study examined hippocampal theta power during configural and non-configural tasks in rats. Experiment 1 compared hippocampal theta power during a negative patterning task (A+, B+, AB-) to a configural task and a simple discrimination task (A+, B-) as a non-configural task. The results showed that hippocampal theta power during the non-reinforcement trial (non-RFT) of the negative patterning task was higher than that during the simple discrimination task. However, this hippocampal power may reflect sensory processing for compound stimuli that have cross-modality features (the non-RFT of the negative patterning task was presented together with visual and auditory stimuli, but the non-RFT of the simple discrimination task was presented with visual or auditory stimulus alone). Thus, in experiment 2, we examined whether the experiment 1 results were attributable to sensory processing of a compound stimulus by comparing hippocampal theta power during negative patterning (A+, B+, AB-), simultaneous feature-negative (A+, AB-), and simple discrimination tasks (A+, B-). Experiment 2 showed that hippocampal theta activity during the non-RFT in the negative patterning task was higher than that in the simultaneous feature-negative and simple discrimination tasks. Thus, we showed that hippocampal theta activity increased during configural tasks but not during non-configural tasks.

  14. Upper Limb Muscle and Brain Activity in Light Assembly Task on Different Load Levels

    NASA Astrophysics Data System (ADS)

    Zadry, Hilma Raimona; Dawal, Siti Zawiah Md.; Taha, Zahari

    2010-10-01

    A study was conducted to investigate the effect of load on upper limb muscles and brain activities in light assembly task. The task was conducted at two levels of load (Low and high). Surface electromyography (EMG) was used to measure upper limb muscle activities of twenty subjects. Electroencephalography (EEG) was simultaneously recorded with EMG to record brain activities from Fz, Pz, O1 and O2 channels. The EMG Mean Power Frequency (MPF) of the right brachioradialis and the left upper trapezius activities were higher on the high-load task compared to low-load task. The EMG MPF values also decrease as time increases, that reflects muscle fatigue. Mean power of the EEG alpha bands for the Fz-Pz channels were found to be higher on the high-load task compared to low-load task, while for the O1-O2 channels, they were higher on the low-load task than on the high-load task. These results indicated that the load levels effect the upper limb muscle and brain activities. The high-load task will increase muscle activities on the right brachioradialis and the left upper tapezius muscles, and will increase the awareness and motivation of the subjects. Whilst the low-load task can generate drowsiness earlier. It signified that the longer the time and the more heavy of the task, the subjects will be more fatigue physically and mentally.

  15. Disentangling stereotype activation and stereotype application in the stereotype misperception task.

    PubMed

    Krieglmeyer, Regina; Sherman, Jeffrey W

    2012-08-01

    When forming impressions about other people, stereotypes about the individual's social group often influence the resulting impression. At least 2 distinguishable processes underlie stereotypic impression formation: stereotype activation and stereotype application. Most previous research has used implicit measures to assess stereotype activation and explicit measures to assess stereotype application, which has several disadvantages. The authors propose a measure of stereotypic impression formation, the stereotype misperception task (SMT), together with a multinomial model that quantitatively disentangles the contributions of stereotype activation and application to responses in the SMT. The validity of the SMT and of the multinomial model was confirmed in 5 studies. The authors hope to advance research on stereotyping by providing a measurement tool that separates multiple processes underlying impression formation. PMID:22663350

  16. Disentangling stereotype activation and stereotype application in the stereotype misperception task.

    PubMed

    Krieglmeyer, Regina; Sherman, Jeffrey W

    2012-08-01

    When forming impressions about other people, stereotypes about the individual's social group often influence the resulting impression. At least 2 distinguishable processes underlie stereotypic impression formation: stereotype activation and stereotype application. Most previous research has used implicit measures to assess stereotype activation and explicit measures to assess stereotype application, which has several disadvantages. The authors propose a measure of stereotypic impression formation, the stereotype misperception task (SMT), together with a multinomial model that quantitatively disentangles the contributions of stereotype activation and application to responses in the SMT. The validity of the SMT and of the multinomial model was confirmed in 5 studies. The authors hope to advance research on stereotyping by providing a measurement tool that separates multiple processes underlying impression formation.

  17. Task-discriminative space-by-time factorization of muscle activity.

    PubMed

    Delis, Ioannis; Panzeri, Stefano; Pozzo, Thierry; Berret, Bastien

    2015-01-01

    Movement generation has been hypothesized to rely on a modular organization of muscle activity. Crucial to this hypothesis is the ability to perform reliably a variety of motor tasks by recruiting a limited set of modules and combining them in a task-dependent manner. Thus far, existing algorithms that extract putative modules of muscle activations, such as Non-negative Matrix Factorization (NMF), identify modular decompositions that maximize the reconstruction of the recorded EMG data. Typically, the functional role of the decompositions, i.e., task accomplishment, is only assessed a posteriori. However, as motor actions are defined in task space, we suggest that motor modules should be computed in task space too. In this study, we propose a new module extraction algorithm, named DsNM3F, that uses task information during the module identification process. DsNM3F extends our previous space-by-time decomposition method (the so-called sNM3F algorithm, which could assess task performance only after having computed modules) to identify modules gauging between two complementary objectives: reconstruction of the original data and reliable discrimination of the performed tasks. We show that DsNM3F recovers the task dependence of module activations more accurately than sNM3F. We also apply it to electromyographic signals recorded during performance of a variety of arm pointing tasks and identify spatial and temporal modules of muscle activity that are highly consistent with previous studies. DsNM3F achieves perfect task categorization without significant loss in data approximation when task information is available and generalizes as well as sNM3F when applied to new data. These findings suggest that the space-by-time decomposition of muscle activity finds robust task-discriminating modular representations of muscle activity and that the insertion of task discrimination objectives is useful for describing the task modulation of module recruitment.

  18. Information Seeking Research Needs Extension towards Tasks and Technology

    ERIC Educational Resources Information Center

    Järvelin, Kalervo; Ingwersen, Peter

    2004-01-01

    This paper discusses the research into information seeking and its directions at a general level. We approach this topic by analysis and argumentation based on past research in the domain. We begin by presenting a general model of information seeking and retrieval which is used to derive nine broad dimensions that are needed to analyze information…

  19. Designing Tasks with Interactive Geometry Applets for Use in Research: Some Methodological Issues

    ERIC Educational Resources Information Center

    Sinclair, Margaret

    2006-01-01

    This paper discusses some of the results of a study carried out with two classes of grade 7 students (11-12 years old); the aim of the project was to design, develop, and test interactive geometry tasks for use in future research into how (or whether) interactive applets help students learn mathematics. The study tasks were developed around the…

  20. Work Task Dimensions Underlying the World of Work: Research Results for Diverse Occupational Databases

    ERIC Educational Resources Information Center

    Prediger, Dale J.; Swaney, Kyle B.

    2004-01-01

    This article reports new research supporting the two bipolar work task dimensions that underlie the World-of-Work Map (WWM) and Holland's hexagon--working with data versus ideas (D/I) and working with things versus people (T/P). Three databases provided diverse perspectives on basic work tasks: (a) general nature of work (expert ratings for 1,122…

  1. Task-Based Language Learning and Teaching: An Action-Research Study

    ERIC Educational Resources Information Center

    Calvert, Megan; Sheen, Younghee

    2015-01-01

    The creation, implementation, and evaluation of language learning tasks remain a challenge for many teachers, especially those with limited experience with using tasks in their teaching. This action-research study reports on one teacher's experience of developing, implementing, critically reflecting on, and modifying a language learning task…

  2. Ethics in Physical Activity Research.

    ERIC Educational Resources Information Center

    Kroll, Walter; And Others

    1993-01-01

    Four conference papers on ethics in physical activity research are presented: (1) "Ethical Issues in Human Research" (W. Kroll); (2) "Ethical Issues in Animal Research" (K. Matt); (3) "Oh What a Tangled Web We Have" (M. Safrit); and (4) "Ethical Issues in Conducting and Reporting Research: A Reaction to Kroll, Matt, and Safrit" (H. Zelaznik). (SM)

  3. The multi-attribute task battery for human operator workload and strategic behavior research

    NASA Technical Reports Server (NTRS)

    Comstock, J. Raymond, Jr.; Arnegard, Ruth J.

    1992-01-01

    The Multi-Attribute Task (MAT) Battery provides a benchmark set of tasks for use in a wide range of lab studies of operator performance and workload. The battery incorporates tasks analogous to activities that aircraft crewmembers perform in flight, while providing a high degree of experimenter control, performance data on each subtask, and freedom to use nonpilot test subjects. Features not found in existing computer based tasks include an auditory communication task (to simulate Air Traffic Control communication), a resource management task permitting many avenues or strategies of maintaining target performance, a scheduling window which gives the operator information about future task demands, and the option of manual or automated control of tasks. Performance data are generated for each subtask. In addition, the task battery may be paused and onscreen workload rating scales presented to the subject. The MAT Battery requires a desktop computer with color graphics. The communication task requires a serial link to a second desktop computer with a voice synthesizer or digitizer card.

  4. Lacan, Subjectivity and the Task of Mathematics Education Research

    ERIC Educational Resources Information Center

    Brown, Tony

    2008-01-01

    This paper addresses the issue of subjectivity in the context of mathematics education research. It introduces the psychoanalyst and theorist Jacques Lacan whose work on subjectivity combined Freud's psychoanalytic theory with processes of signification as developed in the work of de Saussure and Peirce. The paper positions Lacan's subjectivity…

  5. Cognitive tasks in information analysis: Use of event dwell time to characterize component activities

    SciTech Connect

    Sanquist, Thomas F.; Greitzer, Frank L.; Slavich, Antoinette L.; Littlefield, Rik J.; Littlefield, Janis S.; Cowley, Paula J.

    2004-09-28

    Technology-based enhancement of information analysis requires a detailed understanding of the cognitive tasks involved in the process. The information search and report production tasks of the information analysis process were investigated through evaluation of time-stamped workstation data gathered with custom software. Model tasks simulated the search and production activities, and a sample of actual analyst data were also evaluated. Task event durations were calculated on the basis of millisecond-level time stamps, and distributions were plotted for analysis. The data indicate that task event time shows a cyclic pattern of variation, with shorter event durations (< 2 sec) reflecting information search and filtering, and longer event durations (> 10 sec) reflecting information evaluation. Application of cognitive principles to the interpretation of task event time data provides a basis for developing “cognitive signatures” of complex activities, and can facilitate the development of technology aids for information intensive tasks.

  6. Atypical Activation during the Embedded Figures Task as a Functional Magnetic Resonance Imaging Endophenotype of Autism

    ERIC Educational Resources Information Center

    Spencer, Michael D.; Holt, Rosemary J.; Chura, Lindsay R.; Calder, Andrew J.; Suckling, John; Bullmore, Edward T.; Baron-Cohen, Simon

    2012-01-01

    Atypical activation during the Embedded Figures Task has been demonstrated in autism, but has not been investigated in siblings or related to measures of clinical severity. We identified atypical activation during the Embedded Figures Task in participants with autism and unaffected siblings compared with control subjects in a number of temporal…

  7. The past, present and future tasks of Hungarian dendrological research.

    PubMed

    Bartha, D

    2010-01-01

    Hungarian dendrological research (research of living woody plants) has more than 200 years old history; the first general work by János Keresztély Grossinger was published in 1797. Further basic works in our time yet are: Forest Botany by Lajos Fekete and Sándor Mágócsy-Dietz (1896); and the chorological work, Distribution of trees and shrubs of sylvicultural importance in the region of Hungarian State by Lajos Fekete and Tibor Blattny (1913). A few dendrologists and many botanists have helped to get better knowledge of Hungarian dendroflora. From the point of view of taxonomy, chorology and habitat - which are interested by field botanists - it can be said that knowledge is fairly heterogeneous. There are sufficient information about most of the rare (protected/endangered) woody plants (an about 50 species) and the important adventives, above all invasive trees and shrubs (an about 10 species). From these two groups beyond there are only few taxa which can be said thoroughly worked up and known (e.g. Castanea sativa, Cornus mas, Fraxinus spp., Quercus spp.). List of the dendrotaxa, hardly known in the above-mentioned point of view is rich in species that are important for forestry or horticulture (e.g. Alnus glutinosa, Acer spp., Betula pendula, Corylusavellana and most of Salix spp.), supplemented with other species (e.g. Clematis vitalba, Colutea arborescens, Lonicera xylosteum, Padus avium, Sambucus nigra, Staphylea pinnata, Viburnum spp.).Followings can be asked from our field botanists: i) look for a specialist in cases of critical dendrotaxa; ii) a circumspect identification is necessary - especially in the case of leaves - by right of great number of samples from the adequate part of shoot; iii) keep in view frequent hybridization (e.g. in the case of Betula, Crataegus, Pyrus, Tilia), and frequent appearance of hybrids (e.g. Betula × rhombifolia, Cerasus × eminens, Salix × rubens); iv) appearance of interim forms are usually typical in the cases of

  8. Increased Brain Activation for Dual Tasking with 70-Days Head-Down Bed Rest

    PubMed Central

    Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia A.; De Dios, Yiri E.; Gadd, Nichole E.; Wood, Scott J.; Riascos, Roy; Kofman, Igor S.; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.; Seidler, Rachael D.

    2016-01-01

    Head-down tilt bed rest (HDBR) has been used as a spaceflight analog to simulate the effects of microgravity exposure on human physiology, sensorimotor function, and cognition on Earth. Previous studies have reported that concurrent performance of motor and cognitive tasks can be impaired during space missions. Understanding the consequences of HDBR for neural control of dual tasking may possibly provide insight into neural efficiency during spaceflight. In the current study, we evaluated how dual task performance and the underlying brain activation changed as a function of HDBR. Eighteen healthy men participated in this study. They remained continuously in the 6° head-down tilt position for 70 days. Functional MRI for bimanual finger tapping was acquired during both single task and dual task conditions, and repeated at 7 time points pre-, during- and post-HDBR. Another 12 healthy males participated as controls who did not undergo HDBR. A widely distributed network involving the frontal, parietal, cingulate, temporal, and occipital cortices exhibited increased activation for dual tasking and increased activation differences between dual and single task conditions during HDBR relative to pre- or post-HDBR. This HDBR-related brain activation increase for dual tasking implies that more neurocognitive control is needed for dual task execution during HDBR compared to pre- and post-HDBR. We observed a positive correlation between pre-to-post HDBR changes in dual-task cost of reaction time and pre-to-post HDBR change in dual-task cost of brain activation in several cerebral and cerebellar regions. These findings could be predictive of changes in dual task processing during spaceflight.

  9. Increased Brain Activation for Dual Tasking with 70-Days Head-Down Bed Rest.

    PubMed

    Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia A; De Dios, Yiri E; Gadd, Nichole E; Wood, Scott J; Riascos, Roy; Kofman, Igor S; Bloomberg, Jacob J; Mulavara, Ajitkumar P; Seidler, Rachael D

    2016-01-01

    Head-down tilt bed rest (HDBR) has been used as a spaceflight analog to simulate the effects of microgravity exposure on human physiology, sensorimotor function, and cognition on Earth. Previous studies have reported that concurrent performance of motor and cognitive tasks can be impaired during space missions. Understanding the consequences of HDBR for neural control of dual tasking may possibly provide insight into neural efficiency during spaceflight. In the current study, we evaluated how dual task performance and the underlying brain activation changed as a function of HDBR. Eighteen healthy men participated in this study. They remained continuously in the 6° head-down tilt position for 70 days. Functional MRI for bimanual finger tapping was acquired during both single task and dual task conditions, and repeated at 7 time points pre-, during- and post-HDBR. Another 12 healthy males participated as controls who did not undergo HDBR. A widely distributed network involving the frontal, parietal, cingulate, temporal, and occipital cortices exhibited increased activation for dual tasking and increased activation differences between dual and single task conditions during HDBR relative to pre- or post-HDBR. This HDBR-related brain activation increase for dual tasking implies that more neurocognitive control is needed for dual task execution during HDBR compared to pre- and post-HDBR. We observed a positive correlation between pre-to-post HDBR changes in dual-task cost of reaction time and pre-to-post HDBR change in dual-task cost of brain activation in several cerebral and cerebellar regions. These findings could be predictive of changes in dual task processing during spaceflight. PMID:27601982

  10. Increased Brain Activation for Dual Tasking with 70-Days Head-Down Bed Rest

    PubMed Central

    Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia A.; De Dios, Yiri E.; Gadd, Nichole E.; Wood, Scott J.; Riascos, Roy; Kofman, Igor S.; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.; Seidler, Rachael D.

    2016-01-01

    Head-down tilt bed rest (HDBR) has been used as a spaceflight analog to simulate the effects of microgravity exposure on human physiology, sensorimotor function, and cognition on Earth. Previous studies have reported that concurrent performance of motor and cognitive tasks can be impaired during space missions. Understanding the consequences of HDBR for neural control of dual tasking may possibly provide insight into neural efficiency during spaceflight. In the current study, we evaluated how dual task performance and the underlying brain activation changed as a function of HDBR. Eighteen healthy men participated in this study. They remained continuously in the 6° head-down tilt position for 70 days. Functional MRI for bimanual finger tapping was acquired during both single task and dual task conditions, and repeated at 7 time points pre-, during- and post-HDBR. Another 12 healthy males participated as controls who did not undergo HDBR. A widely distributed network involving the frontal, parietal, cingulate, temporal, and occipital cortices exhibited increased activation for dual tasking and increased activation differences between dual and single task conditions during HDBR relative to pre- or post-HDBR. This HDBR-related brain activation increase for dual tasking implies that more neurocognitive control is needed for dual task execution during HDBR compared to pre- and post-HDBR. We observed a positive correlation between pre-to-post HDBR changes in dual-task cost of reaction time and pre-to-post HDBR change in dual-task cost of brain activation in several cerebral and cerebellar regions. These findings could be predictive of changes in dual task processing during spaceflight. PMID:27601982

  11. Advances in Activity Cliff Research.

    PubMed

    Dimova, Dilyana; Bajorath, Jürgen

    2016-05-01

    Activity cliffs, i.e. similar compounds with large potency differences, are of interest from a chemical and informatics viewpoint; as a source of structure-activity relationship information, for compound optimization, and activity prediction. Herein, recent highlights of activity cliff research are discussed including studies that have further extended our understanding of activity cliffs, yielded unprecedented insights, or paved the way for practical applications.

  12. Advances in Activity Cliff Research.

    PubMed

    Dimova, Dilyana; Bajorath, Jürgen

    2016-05-01

    Activity cliffs, i.e. similar compounds with large potency differences, are of interest from a chemical and informatics viewpoint; as a source of structure-activity relationship information, for compound optimization, and activity prediction. Herein, recent highlights of activity cliff research are discussed including studies that have further extended our understanding of activity cliffs, yielded unprecedented insights, or paved the way for practical applications. PMID:27492084

  13. Individual differences in oscillatory brain activity in response to varying attentional demands during a word recall and oculomotor dual task

    PubMed Central

    Kwon, Gusang; Lim, Sanghyun; Kim, Min-Young; Kwon, Hyukchan; Lee, Yong-Ho; Kim, Kiwoong; Lee, Eun-Ju; Suh, Minah

    2015-01-01

    Every day, we face situations that involve multi-tasking. How our brain utilizes cortical resources during multi-tasking is one of many interesting research topics. In this study, we tested whether a dual-task can be differentiated in the neural and behavioral responses of healthy subjects with varying degree of working memory capacity (WMC). We combined word recall and oculomotor tasks because they incorporate common neural networks including the fronto-parietal (FP) network. Three different types of oculomotor tasks (eye fixation, Fix-EM; predictive and random smooth pursuit eye movement, P-SPEM and R-SPEM) were combined with two memory load levels (low-load: five words, high-load: 10 words) for a word recall task. Each of those dual-task combinations was supposed to create varying cognitive loads on the FP network. We hypothesize that each dual-task requires different cognitive strategies for allocating the brain’s limited cortical resources and affects brain oscillation of the FP network. In addition, we hypothesized that groups with different WMC will show differential neural and behavioral responses. We measured oscillatory brain activity with simultaneous MEG and EEG recordings and behavioral performance by word recall. Prominent frontal midline (FM) theta (4–6 Hz) synchronization emerged in the EEG of the high-WMC group experiencing R-SPEM with high-load conditions during the early phase of the word maintenance period. Conversely, significant parietal upper alpha (10–12 Hz) desynchronization was observed in the EEG and MEG of the low-WMC group experiencing P-SPEM under high-load conditions during the same period. Different brain oscillatory patterns seem to depend on each individual’s WMC and varying attentional demands from different dual-task combinations. These findings suggest that specific brain oscillations may reflect different strategies for allocating cortical resources during combined word recall and oculomotor dual-tasks. PMID:26175681

  14. Development and Validation of Career Development Guidelines by Task/Activity Analysis of Occupational Safety and Health Professions: Industrial Hygiene and Safety Professional. Final Report. Technical Report XII.

    ERIC Educational Resources Information Center

    Vernon, Ralph J.; And Others

    This report summarizes research findings which resulted in development of curricula for occupational safety and health professions based on task/activity analyses and related performance objectives. The first seven chapters focus on the seven objectives. Chapter 1, Literature Review and Selection of Employers, concerns tasks required for…

  15. The Tell-Tale Tasks: A Review of Saccadic Research in Psychiatric Patient Populations

    ERIC Educational Resources Information Center

    Gooding, Diane C.; Basso, Michele A.

    2008-01-01

    This review focuses on saccade research with adult psychiatric patients. It begins with an introduction of the various types of saccades and the tasks used to evoke them. The functional significance of the different types of eye movements is briefly discussed. Research findings regarding the saccadic performance of different adult psychiatric…

  16. Integrated Extravehicular Activity Human Research Plan: 2016

    NASA Technical Reports Server (NTRS)

    Abercromby, Andrew F. J.; Ross, Amy J.; Cupples, J. Scott; Rajulu, Sudhakar; Norcross, Jason R.; Chappell, Steven P.

    2016-01-01

    Multiple organizations within NASA and outside of NASA fund and participate in research related to extravehicular activity (EVA). In October 2015, representatives of the EVA Office, the Crew and Thermal Systems Division (CTSD), and the Human Research Program (HRP) at NASA Johnson Space Center agreed on a formal framework to improve multi-year coordination and collaboration in EVA research. At the core of the framework is an Integrated EVA Human Research Plan and a process by which it will be annually reviewed and updated. The over-arching objective of the collaborative framework is to conduct multi-disciplinary cost-effective research that will enable humans to perform EVAs safely, effectively, comfortably, and efficiently, as needed to enable and enhance human space exploration missions. Research activities must be defined, prioritized, planned and executed to comprehensively address the right questions, avoid duplication, leverage other complementary activities where possible, and ultimately provide actionable evidence-based results in time to inform subsequent tests, developments and/or research activities. Representation of all appropriate stakeholders in the definition, prioritization, planning and execution of research activities is essential to accomplishing the over-arching objective. A formal review of the Integrated EVA Human Research Plan will be conducted annually. External peer review of all HRP EVA research activities including compilation and review of published literature in the EVA Evidence Report is will also continue at a frequency determined by HRP management. Coordination with stakeholders outside of the EVA Office, CTSD, and HRP is already in effect on a study-by-study basis; closer coordination on multi-year planning with other EVA stakeholders including academia is being actively pursued. Details of the current Integrated EVA Human Research Plan are presented including description of ongoing and planned research activities in the areas of

  17. Trunk postures and upper-body muscle activations during physically demanding wildfire suppression tasks.

    PubMed

    Neesham-Smith, Daniel; Aisbett, Brad; Netto, Kevin

    2014-01-01

    This study examined the trunk postures and upper-body muscle activations during four physically demanding wildfire suppression tasks. Bilateral, wireless surface electromyography was recorded from the trapezius and erector spinae muscles of nine experienced, wildfire fighters. Synchronised video captured two retroreflective markers to allow for quantification of two-dimensional sagittal trunk flexion. In all tasks, significantly longer time was spent in the mild and severe trunk flexion (p ≤ 0.002) compared to the time spent in a neutral posture. Mean and peak muscle activation in all tasks exceeded previously established safe limits. These activation levels also significantly increased through the performance of each task (p < 0.001). The results suggest that the wildfire suppression tasks analysed impose significant musculoskeletal demand on firefighters. Fire agencies should consider developing interventions to reduce the exposure of their personnel to these potentially injurious musculoskeletal demands.

  18. Trunk postures and upper-body muscle activations during physically demanding wildfire suppression tasks.

    PubMed

    Neesham-Smith, Daniel; Aisbett, Brad; Netto, Kevin

    2014-01-01

    This study examined the trunk postures and upper-body muscle activations during four physically demanding wildfire suppression tasks. Bilateral, wireless surface electromyography was recorded from the trapezius and erector spinae muscles of nine experienced, wildfire fighters. Synchronised video captured two retroreflective markers to allow for quantification of two-dimensional sagittal trunk flexion. In all tasks, significantly longer time was spent in the mild and severe trunk flexion (p ≤ 0.002) compared to the time spent in a neutral posture. Mean and peak muscle activation in all tasks exceeded previously established safe limits. These activation levels also significantly increased through the performance of each task (p < 0.001). The results suggest that the wildfire suppression tasks analysed impose significant musculoskeletal demand on firefighters. Fire agencies should consider developing interventions to reduce the exposure of their personnel to these potentially injurious musculoskeletal demands. PMID:24365452

  19. Studying modulation on simultaneously activated SSVEP neural networks by a cognitive task.

    PubMed

    Wu, Zhenghua

    2014-01-01

    Since the discovery of steady-state visually evoked potential (SSVEP), it has been used in many fields. Numerous studies suggest that there exist three SSVEP neural networks in different frequency bands. An obvious phenomenon has been observed, that the amplitude and phase of SSVEP can be modulated by a cognitive task. Previous works have studied this modulation on separately activated SSVEP neural networks by a cognitive task. If two or more SSVEP neural networks are activated simultaneously in the process of a cognitive task, is the modulation on different SSVEP neural networks the same? In this study, two different SSVEP neural networks were activated simultaneously by two different frequency flickers, with a working memory task irrelevant to the flickers being conducted at the same time. The modulated SSVEP waves were compared with each other and to those only under one flicker in previous studies. The comparison results show that the cognitive task can modulate different SSVEP neural networks with a similar style.

  20. Brain activity during divided and selective attention to auditory and visual sentence comprehension tasks

    PubMed Central

    Moisala, Mona; Salmela, Viljami; Salo, Emma; Carlson, Synnöve; Vuontela, Virve; Salonen, Oili; Alho, Kimmo

    2015-01-01

    Using functional magnetic resonance imaging (fMRI), we measured brain activity of human participants while they performed a sentence congruence judgment task in either the visual or auditory modality separately, or in both modalities simultaneously. Significant performance decrements were observed when attention was divided between the two modalities compared with when one modality was selectively attended. Compared with selective attention (i.e., single tasking), divided attention (i.e., dual-tasking) did not recruit additional cortical regions, but resulted in increased activity in medial and lateral frontal regions which were also activated by the component tasks when performed separately. Areas involved in semantic language processing were revealed predominantly in the left lateral prefrontal cortex by contrasting incongruent with congruent sentences. These areas also showed significant activity increases during divided attention in relation to selective attention. In the sensory cortices, no crossmodal inhibition was observed during divided attention when compared with selective attention to one modality. Our results suggest that the observed performance decrements during dual-tasking are due to interference of the two tasks because they utilize the same part of the cortex. Moreover, semantic dual-tasking did not appear to recruit additional brain areas in comparison with single tasking, and no crossmodal inhibition was observed during intermodal divided attention. PMID:25745395

  1. Cognitive Activities in Solving Mathematical Tasks: The Role of a Cognitive Obstacle

    ERIC Educational Resources Information Center

    Antonijevic, Radovan

    2016-01-01

    In the process of learning mathematics, students practice various forms of thinking activities aimed to substantially contribute to the development of their different cognitive structures. In this paper, the subject matter is a "cognitive obstacle", a phenomenon that occurs in the procedures of solving mathematical tasks. Each task in…

  2. A Goal Activation Approach to the Study of Executive Function: An Application to Antisaccade Tasks

    ERIC Educational Resources Information Center

    Nieuwenhuis, Sander; Broerse, Annelies; Nielen, Marjan M. A.; de Jong, Ritske

    2004-01-01

    We argue that a general control process, responsible for the activation and maintenance of task goals, is central to the concept of executive function. Failures of this process can become manifest as "goal neglect": disregard of a task requirement even though it has been understood (Duncan, 1995). We discuss the results of several published and…

  3. A Cross-Cultural Investigation into How Tasks Influence Seatwork Activities in Mathematics Lessons

    ERIC Educational Resources Information Center

    Serrano, Ana M.

    2012-01-01

    This study examined how types of tasks influenced student activities/thinking and defined the role of Seatwork in mathematics lessons. It used 60 lessons from the TIMSS videotaped Study. These data indicated that practice was the most prevalent form of tasks in the U.S. In Germany, students completed mathematical calculations after a complex…

  4. Advanced Marketing 8130. Instructional Areas. Duties and Tasks. Learning Activities. Referenced Resources.

    ERIC Educational Resources Information Center

    Virginia State Dept. of Education, Richmond.

    This resource handbook, which is designed for use by instructors of courses in advanced marketing, consists of a duty/task list with referenced resources, a duty/task list with learning activities, and a list of resources. Included in each list are materials dealing with the following topics: communication in marketing, economics in marketing,…

  5. Children's Performance on a False-belief Task Is Impaired by Activation of an Evolutionarily-Canalized Response System.

    ERIC Educational Resources Information Center

    Keenan, Thomas; Ellis, Bruce J.

    2003-01-01

    Two studies examined how task content that activates predator-avoidance affects preschool children's performance on a false-belief task. Findings indicated that the proportion of correct answers on the playmate-avoidance task was greater than that for the predator-avoidance task, suggesting that activation of the predator-avoidance system…

  6. Investigating the muscle activities of performing surgical training tasks using a virtual simulator.

    PubMed

    Huang, Chun-Kai; Suh, Irene H; Chien, Jung Hung; Vallabhajosula, Srikant; Oleynikov, Dmitry; Siu, Ka-Chun

    2012-01-01

    The objective of this study was to determine the muscle activities of upper extremities while performing fundamental surgical training tasks using a virtual simulator. Six subjects performed virtual cutting tasks and their muscle activities of upper extremities were measured. The results demonstrated a significant increase in muscle activities in both proximal and distal upper extremities, which are the common areas of occurrence of injury after prolonged practice. This study suggests that the upper trapezius and the extensor digitorum are essential prime movers to perform surgical training tasks. These muscles should be monitored for performance assessment in future studies.

  7. Effects of task-oriented training on upper extremity function and performance of daily activities by chronic stroke patients

    PubMed Central

    Park, JuHyung; Yoo, Chanuk

    2015-01-01

    [Purpose] The aim of this study was to determine the effects that task-oriented training has on upper extremity function and performance of daily activities by chronic stroke patients. [Subjects and Methods] Task-oriented training was applied to two chronic hemiplegic patients in this research. The training was provided to each patient for 30 minutes a day, five times a week for two weeks. The treatment program included six different types of training that could be performed by the patients themselves. Evaluation was performed four times, that is, once a week for three weeks before the intervention and once after the intervention. The change in upper extremity function was measured with the Manual Function Test, and the change in performance of daily activity was measured with the Functional Independence Measure. [Results] The upper extremity function of both subjects was improved after application of task-oriented training. However, in the performance of daily activities, subject one showed improvement compared to with before the intervention, whereas subject two showed the same results. [Conclusion] This research confirmed that two weeks of task-oriented training for chronic stroke patients is effective for improvement of upper extremity function and performance of daily activities by chronic stroke patients. PMID:26355425

  8. The role of peer groups in male and female adolescents' task values and physical activity.

    PubMed

    Yli-Piipari, Sami; Jaakkola, Timo; Liukkonen, Jarmo; Kiuru, Noona; Watt, Anthony

    2011-02-01

    The purpose of this longitudinal study was to examine the role of peer groups and sex in adolescents' task values and physical activity. The participants were 330 Finnish Grade 6 students (173 girls, 157 boys), who responded to questionnaires that assessed physical education task values during the spring semester (Time 1). Students' physical activity was assessed one year later (Time 2). The results indicated that adolescent peer groups were moderately homogeneous in terms of task values toward physical education and physical activity. Girls' peer groups were more homogeneous than those of boys in regards to utility and attainment values. Furthermore, the results for both girls and boys showed that particularly intrinsic task value typical for the peer group predicted group members' physical activity. The findings highlight the important role of peer group membership as a determinant of future physical activity. PMID:21526593

  9. Task discrimination from myoelectric activity: a learning scheme for EMG-based interfaces.

    PubMed

    Liarokapis, Minas V; Artemiadis, Panagiotis K; Kyriakopoulos, Kostas J

    2013-06-01

    A learning scheme based on Random Forests is used to discriminate the task to be executed using only myoelectric activity from the upper limb. Three different task features can be discriminated: subspace to move towards, object to be grasped and task to be executed (with the object). The discrimination between the different reach to grasp movements is accomplished with a random forests classifier, which is able to perform efficient features selection, helping us to reduce the number of EMG channels required for task discrimination. The proposed scheme can take advantage of both a classifier and a regressor that cooperate advantageously to split the task space, providing better estimation accuracy with task-specific EMG-based motion decoding models, as reported in [1] and [2]. The whole learning scheme can be used by a series of EMG-based interfaces, that can be found in rehabilitation cases and neural prostheses.

  10. Research and Development. Laboratory Activities.

    ERIC Educational Resources Information Center

    Gallaway, Ann, Ed.

    Research and Development is a laboratory-oriented course that includes the appropriate common essential elements for industrial technology education plus concepts and skills related to research and development. This guide provides teachers of the course with learning activities for secondary students. Introductory materials include an…

  11. Research on multirobot pursuit task allocation algorithm based on emotional cooperation factor.

    PubMed

    Fang, Baofu; Chen, Lu; Wang, Hao; Dai, Shuanglu; Zhong, Qiubo

    2014-01-01

    Multirobot task allocation is a hot issue in the field of robot research. A new emotional model is used with the self-interested robot, which gives a new way to measure self-interested robots' individual cooperative willingness in the problem of multirobot task allocation. Emotional cooperation factor is introduced into self-interested robot; it is updated based on emotional attenuation and external stimuli. Then a multirobot pursuit task allocation algorithm is proposed, which is based on emotional cooperation factor. Combined with the two-step auction algorithm recruiting team leaders and team collaborators, set up pursuit teams, and finally use certain strategies to complete the pursuit task. In order to verify the effectiveness of this algorithm, some comparing experiments have been done with the instantaneous greedy optimal auction algorithm; the results of experiments show that the total pursuit time and total team revenue can be optimized by using this algorithm.

  12. SHINE Tritium Nozzle Design: Activity 6, Task 1 Report

    SciTech Connect

    Okhuysen, Brett S.; Pulliam, Elias Noel

    2015-11-05

    In FY14, we studied the qualitative and quantitative behavior of a SHINE/PNL tritium nozzle under varying operating conditions. The result is an understanding of the nozzle’s performance in terms of important flow features that manifest themselves under different parametric profiles. In FY15, we will consider nozzle design with a focus on nozzle geometry and integration. From FY14 work, we will understand how the SHINE/PNL nozzle behaves under different operating scenarios. The first task for FY15 is to evaluate the FY14 model as a predictor of the actual flow. Considering different geometries is more time-intensive than parameter studies, therefore we recommend considering any relevant flow features that were not included in the FY14 model. In the absence of experimental data, it is particularly important to consider any sources of heat in the domain or boundary conditions that may affect the flow and incorporate these into the simulation if they are significant. Additionally, any geometric features of the beamline segment should be added to the model such as the orifice plate. The FY14 model works with hydrogen. An improvement that can be made for FY15 is to develop CFD properties for tritium and incorporate those properties into the new models.

  13. Reward sensitivity modulates brain activity in the prefrontal cortex, ACC and striatum during task switching.

    PubMed

    Fuentes-Claramonte, Paola; Ávila, César; Rodríguez-Pujadas, Aina; Ventura-Campos, Noelia; Bustamante, Juan C; Costumero, Víctor; Rosell-Negre, Patricia; Barrós-Loscertales, Alfonso

    2015-01-01

    Current perspectives on cognitive control acknowledge that individual differences in motivational dispositions may modulate cognitive processes in the absence of reward contingencies. This work aimed to study the relationship between individual differences in Behavioral Activation System (BAS) sensitivity and the neural underpinnings involved in processing a switching cue in a task-switching paradigm. BAS sensitivity was hypothesized to modulate brain activity in frontal regions, ACC and the striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task, which elicited activity in fronto-striatal regions during the processing of the switch cue. BAS sensitivity was negatively associated with activity in the lateral prefrontal cortex, anterior cingulate cortex and the ventral striatum. Combined with previous results, our data indicate that BAS sensitivity modulates the neurocognitive processes involved in task switching in a complex manner depending on task demands. Therefore, individual differences in motivational dispositions may influence cognitive processing in the absence of reward contingencies.

  14. Reward Sensitivity Modulates Brain Activity in the Prefrontal Cortex, ACC and Striatum during Task Switching

    PubMed Central

    Fuentes-Claramonte, Paola; Ávila, César; Rodríguez-Pujadas, Aina; Ventura-Campos, Noelia; Bustamante, Juan C.; Costumero, Víctor; Rosell-Negre, Patricia; Barrós-Loscertales, Alfonso

    2015-01-01

    Current perspectives on cognitive control acknowledge that individual differences in motivational dispositions may modulate cognitive processes in the absence of reward contingencies. This work aimed to study the relationship between individual differences in Behavioral Activation System (BAS) sensitivity and the neural underpinnings involved in processing a switching cue in a task-switching paradigm. BAS sensitivity was hypothesized to modulate brain activity in frontal regions, ACC and the striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task, which elicited activity in fronto-striatal regions during the processing of the switch cue. BAS sensitivity was negatively associated with activity in the lateral prefrontal cortex, anterior cingulate cortex and the ventral striatum. Combined with previous results, our data indicate that BAS sensitivity modulates the neurocognitive processes involved in task switching in a complex manner depending on task demands. Therefore, individual differences in motivational dispositions may influence cognitive processing in the absence of reward contingencies. PMID:25875640

  15. Reward sensitivity modulates brain activity in the prefrontal cortex, ACC and striatum during task switching.

    PubMed

    Fuentes-Claramonte, Paola; Ávila, César; Rodríguez-Pujadas, Aina; Ventura-Campos, Noelia; Bustamante, Juan C; Costumero, Víctor; Rosell-Negre, Patricia; Barrós-Loscertales, Alfonso

    2015-01-01

    Current perspectives on cognitive control acknowledge that individual differences in motivational dispositions may modulate cognitive processes in the absence of reward contingencies. This work aimed to study the relationship between individual differences in Behavioral Activation System (BAS) sensitivity and the neural underpinnings involved in processing a switching cue in a task-switching paradigm. BAS sensitivity was hypothesized to modulate brain activity in frontal regions, ACC and the striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task, which elicited activity in fronto-striatal regions during the processing of the switch cue. BAS sensitivity was negatively associated with activity in the lateral prefrontal cortex, anterior cingulate cortex and the ventral striatum. Combined with previous results, our data indicate that BAS sensitivity modulates the neurocognitive processes involved in task switching in a complex manner depending on task demands. Therefore, individual differences in motivational dispositions may influence cognitive processing in the absence of reward contingencies. PMID:25875640

  16. PHARMACOLOGICAL INTERVENTIONS IN FRAILTY AND SARCOPENIA: REPORT BY THE INTERNATIONAL CONFERENCE ON FRAILTY AND SARCOPENIA RESEARCH TASK FORCE

    PubMed Central

    Cesari, M.; Fielding, R.; Bénichou, O.; Bernabei, R.; Bhasin, S.; Guralnik, J.M.; Jette, A.; Landi, F.; Pahor, M.; Rodriguez-Manas, L.; Rolland, Y.; Roubenoff, R.; Sinclair, A.J.; Studenski, S.; Travison, T.; Vellas, B.

    2015-01-01

    Sarcopenia and frailty often co-exist and both have physical function impairment as a core component. Yet despite the urgency of the problem, the development of pharmaceutical therapies for sarcopenia and frailty has lagged, in part because of the lack of consensus definitions for the two conditions. A task force of clinical and basic researchers, leaders from the pharmaceutical and nutritional industries, and representatives from non-profit organizations was established in 2012 with the aim of addressing specific issues affecting research and clinical activities on frailty and sarcopenia. The task force came together on April 22, 2015 in Boston, Massachusetts, prior to the International Conference on Frailty and Sarcopenia Research (ICFSR). The theme of this meeting was to discuss challenges related to drugs designed to target the biology of frailty and sarcopenia as well as more general questions about designing efficient drug trials for these conditions. The present article reports the results of the task force’s deliberations based on available evidence and preliminary results of ongoing activities. Overall, the lack of a consensus definition for sarcopenia and frailty was felt as still present and severely limiting advancements in the field. However, agreement appears to be emerging that low mass alone provides insufficient clinical relevance if not combined with muscle weakness and/or functional impairment. In the next future, it will be important to build consensus on clinically meaningful functional outcomes and test/validate them in long-term observational studies. PMID:26366378

  17. Development of statistical models for predicting muscle and mental activities during repetitive precision tasks.

    PubMed

    Zadry, Hilma Raimona; Dawal, Siti Zawiah Md; Taha, Zahari

    2016-09-01

    This study was conducted to develop muscle and mental activities on repetitive precision tasks. A laboratory experiment was used to address the objectives. Surface electromyography was used to measure muscle activities from eight upper limb muscles, while electroencephalography recorded mental activities from six channels. Fourteen university students participated in the study. The results show that muscle and mental activities increase for all tasks, indicating the occurrence of muscle and mental fatigue. A linear relationship between muscle activity, mental activity and time was found while subjects were performing the task. Thus, models were developed using those variables. The models were found valid after validation using other students' and workers' data. Findings from this study can contribute as a reference for future studies investigating muscle and mental activity and can be applied in industry as guidelines to manage muscle and mental fatigue, especially to manage job schedules and rotation. PMID:27053140

  18. Climate Change, Permafrost and Infrastructure: Task Force Report of the U.S. Arctic Research Commission

    NASA Astrophysics Data System (ADS)

    Brigham, L. W.; Nelson, F. E.

    2003-12-01

    During 2002 the U.S. Arctic Research Commission chartered a task force on climate change, permafrost and infrastructure impacts. The task force was asked to identify key issues and research needs to foster a greater understanding of global change impacts on permafrost in the Arctic and their importance to natural and human systems. Permafrost was found to play three key roles in the context of climatic change: as a record keeper by functioning as a temperature archive; as a translator of climate change through subsidence and related impacts; and, as a facilitator of further change through its impacts on the global carbon cycle. Evidence of widespread warming of permafrost and observations of thawing have serious implications for Alaska's transportation network, for the trans-Alaska pipeline, and for nearly 100,000 Alaskans living in areas of permafrost. These impacts resulting from changing permafrost must be met by a timely, well-informed, and coordinated response by a host of federal and state organizations. Key task force findings include: requirements for a dedicated U.S. federal permafrost research program; data management needs; baseline permafrost mapping in Alaska; basic permafrost research focusing on process studies and modeling; and, applied permafrost research on design criteria and contaminants in permafrost environments. This report to the Commissioners makes specific recommendations to seven federal agencies, the State of Alaska, and the National Research Council. These recommendations will be incorporated in future Arctic research planning documents of the U.S. Arctic Research Commission.

  19. Task Descriptions in Diagnostic Radiology. Research Report No. 7. Volume 3, Machine-Related, Patient Care and Administrative Tasks: What Radiologists, Technologists, Nurses and Physicists Do to Run Things and Look After Patients and Equipment.

    ERIC Educational Resources Information Center

    Gilpatrick, Eleanor

    The third of four volumes in Research Report No. 7 of the Health Services Mobility Study (HSMS), this book contains 149 diagnostic radiologist task descriptions that cover activities in the area of nursing (patient care), film processing, quality assurance, radiation protection, machine maintenance, housekeeping, and administration at the…

  20. Motivated cognitive control: Reward incentives modulate preparatory neural activity during task-switching

    PubMed Central

    Savine, Adam C.; Braver, Todd S.

    2010-01-01

    It is increasingly appreciated that executive control processes need to be understood in terms of motivational as well as cognitive mechanisms. The current study examined the impact of performance-contingent reward incentives (monetary bonuses) on neural activity dynamics during cued task-switching performance. Behavioral measures indicated that performance was improved and task-switch costs selectively reduced on incentive trials. Trial-by-trial fluctuations in incentive value were associated with activation in reward-related brain regions (dopaminergic midbrain, paracingulate cortex) and also modulated the dynamics of switch-selective activation in the brain cognitive control network in both an additive (posterior PFC) and interactive way (dorsolateral PFC, dorsomedial PFC, and inferior parietal cortex). In dorsolateral PFC, incentive-modulation of activation predicted task-switching behavioral performance effects in a hemispherically specialized manner. Further, in left dorsolateral PFC, incentive modulation specifically enhanced task-cue related activation, and this activation in turn predicted that the trial would be subsequently rewarded (due to optimal performance). The results suggest that motivational incentives have a selective effect on brain regions that subserve cognitive control processes during task-switching, and moreover, that one mechanism of effect might be the enhancement of cue-related task preparation within left dorsolateral PFC. PMID:20685974

  1. Supplement to Task Force Report on Rural Development Research in the Northeast for the Next Five Years--A Framework. Publication 1.

    ERIC Educational Resources Information Center

    Harrington, Clifford R., Comp.; Glock, Sandra, Comp.

    Prepared by the Task Force on Rural Development Research (appointed by the U.S. Department of Agriculture), this analytical directory gives primary emphasis to 133 Rural Development 1 (RD1) research projects which were "active" projects between January 1 and June 30, 1973 in 13 Northeastern state agricultural experiment stations and the 2…

  2. Authentic Tasks: A Participatory Action Research Study on a Teaching Method for the Inclusive Classroom

    ERIC Educational Resources Information Center

    Bruffy, Wendy Raso

    2012-01-01

    The way in which education is taught is forever changing. Therefore, a new method in which content is delivered is a central component in examining areas for improvement. In this paper, participatory action research (PAR) was used to investigate authentic tasks in the inclusive tenth and eleventh grade classroom. The purpose of this study was to…

  3. The Information Search Process: A Study of Elements Associated with Meaningful Research Tasks.

    ERIC Educational Resources Information Center

    Garland, Kathleen

    1995-01-01

    Describes a study at a Michigan high school that investigated elements that contributed to a meaningful library research task. Highlights include information literacy; students' feelings of satisfaction and achievement; student questionnaires and student and teacher interviews; group work; and process instruction. (LRW)

  4. The Information Search Process: A Study of Elements Associated with Meaningful Research Tasks.

    ERIC Educational Resources Information Center

    Garland, Kathleen

    1995-01-01

    Describes a study that investigated research projects at a secondary professional development school to determine successful task factors. Results show that student choice of topic, group work, topics related to course content, clear communication by teachers of goals and evaluation methods, and process instruction were related to student…

  5. Using Antecedent Physical Activity to Increase On-Task Behavior in Young Children

    ERIC Educational Resources Information Center

    Luke, Sara; Vail, Cynthia O.; Ayres, Kevin M.

    2014-01-01

    A withdrawal design was used to investigate how physical activity affects on-task behavior of young children with significant developmental delays in a special education preschool classroom. Five preschool age children with significant developmental delays engaged in either physical activity or seated center activities for 20 min prior to a 15-min…

  6. Failing to deactivate: the association between brain activity during a working memory task and creativity.

    PubMed

    Takeuchi, Hikaru; Taki, Yasuyuki; Hashizume, Hiroshi; Sassa, Yuko; Nagase, Tomomi; Nouchi, Rui; Kawashima, Ryuta

    2011-03-15

    Working memory (WM) is an essential component for human higher order cognitive activities. Creativity has been essential to the development of human civilization. Previous studies from different fields have suggested creativity and capacity of WM have opposing characteristics possibly in terms of diffuse attention. However, despite a number of functional imaging studies on creativity, how creativity relates to brain activity during WM has never been investigated. In this functional magnetic resonance imaging (fMRI) study, we investigated this issue using an n-back WM paradigm and a psychometric measure of creativity (a divergent thinking test). A multiple regression analysis revealed that individual creativity was significantly and positively correlated with brain activity in the precuneus during the 2-back task (WM task), but not during the non-WM 0-back task. As the precuneus shows deactivation during cognitive tasks, our findings show that reduced task induced deactivation (TID) in the precuneus is associated with higher creativity measured by divergent thinking. The precuneus is included in the default mode network, which is deactivated during cognitive tasks. The magnitude of TID in the default mode network is considered to reflect the reallocation of cognitive resources from networks irrelevant to the performance of the task. Thus, our findings may indicate that individual creativity, as measured by the divergent thinking test, is related to the inefficient reallocation of attention, congruent with the idea that diffuse attention is associated with individual creativity.

  7. Individual differences in neural activity during a facial expression vs. identity working memory task.

    PubMed

    Neta, Maital; Whalen, Paul J

    2011-06-01

    Facial expressions of emotion constitute a critical portion of our non-verbal social interactions. In addition, the identity of the individual displaying this expression is critical to these interactions as they embody the context in which these expressions will be interpreted. To identify any overlapping and/or unique brain circuitry involved in the processing of these two information streams in a laboratory setting, participants performed a working memory (WM) task (i.e., n-back) in which they were instructed to monitor either the expression (EMO) or the identity (ID) of the same set of face stimuli. Consistent with previous work, during both the EMO and ID tasks, we found a significant increase in activity in dorsolateral prefrontal cortex (DLPFC) supporting its generalized role in WM. Further, individuals that showed greater DLPFC activity during both tasks also showed increased amygdala activity during the EMO task and increased lateral fusiform gyrus activity during the ID task. Importantly, the level of activity in these regions significantly correlated with performance on the respective tasks. These findings provide support for two separate neural circuitries, both involving the DLPFC, supporting working memory for the faces and expressions of others. PMID:21349341

  8. Time estimation as a secondary task to measure workload: Summary of research

    NASA Technical Reports Server (NTRS)

    Hart, S. G.; Mcpherson, D.; Loomis, L. L.

    1978-01-01

    Actively produced intervals of time were found to increase in length and variability, whereas retrospectively produced intervals decreased in length although they also increased in variability with the addition of a variety of flight-related tasks. If pilots counted aloud while making a production, however, the impact of concurrent activity was minimized, at least for the moderately demanding primary tasks that were selected. The effects of feedback on estimation accuracy and consistency were greatly enhanced if a counting or tapping production technique was used. This compares with the minimal effect that feedback had when no overt timekeeping technique was used. Actively made verbal estimates of sessions filled with different activities performed during the interval were increased. Retrospectively made verbal estimates, however, increased in length as the amount and complexity of activities performed during the interval were increased.

  9. Activities report of PTT Research

    NASA Astrophysics Data System (ADS)

    In the field of postal infrastructure research, activities were performed on postcode readers, radiolabels, and techniques of operations research and artificial intelligence. In the field of telecommunication, transportation, and information, research was made on multipurpose coding schemes, speech recognition, hypertext, a multimedia information server, security of electronic data interchange, document retrieval, improvement of the quality of user interfaces, domotics living support (techniques), and standardization of telecommunication prototcols. In the field of telecommunication infrastructure and provisions research, activities were performed on universal personal telecommunications, advanced broadband network technologies, coherent techniques, measurement of audio quality, near field facilities, local beam communication, local area networks, network security, coupling of broadband and narrowband integrated services digital networks, digital mapping, and standardization of protocols.

  10. Age-Related Changes in Brain Activation Underlying Single- and Dual-Task Performance: Visuomanual Drawing and Mental Arithmetic

    ERIC Educational Resources Information Center

    Van Impe, A.; Coxon, J. P.; Goble, D. J.; Wenderoth, N.; Swinnen, S. P.

    2011-01-01

    Depending on task combination, dual-tasking can either be performed successfully or can lead to performance decrements in one or both tasks. Interference is believed to be caused by limitations in central processing, i.e. structural interference between the neural activation patterns associated with each task. In the present study, single- and…

  11. Central as well as Peripheral Attentional Bottlenecks in Dual-Task Performance Activate Lateral Prefrontal Cortices

    PubMed Central

    Szameitat, André J.; Vanloo, Azonya; Müller, Hermann J.

    2016-01-01

    Human information processing suffers from severe limitations in parallel processing. In particular, when required to respond to two stimuli in rapid succession, processing bottlenecks may appear at central and peripheral stages of task processing. Importantly, it has been suggested that executive functions are needed to resolve the interference arising at such bottlenecks. The aims of the present study were to test whether central attentional limitations (i.e., bottleneck at the decisional response selection stage) as well as peripheral limitations (i.e., bottleneck at response initiation) both demand executive functions located in the lateral prefrontal cortex. For this, we re-analyzed two previous studies, in which a total of 33 participants performed a dual-task according to the paradigm of the psychological refractory period (PRP) during functional magnetic resonance imaging (fMRI). In one study (N = 17), the PRP task consisted of two two-choice response tasks known to suffer from a central bottleneck (CB group). In the other study (N = 16), the PRP task consisted of two simple-response tasks known to suffer from a peripheral bottleneck (PB group). Both groups showed considerable dual-task costs in form of slowing of the second response in the dual-task (PRP effect). Imaging results are based on the subtraction of both single-tasks from the dual-task within each group. In the CB group, the bilateral middle frontal gyri and inferior frontal gyri were activated. Higher activation in these areas was associated with lower dual-task costs. In the PB group, the right middle frontal and inferior frontal gyrus (IFG) were activated. Here, higher activation was associated with higher dual-task costs. In conclusion we suggest that central and peripheral bottlenecks both demand executive functions located in lateral prefrontal cortices (LPFC). Differences between the CB and PB groups with respect to the exact prefrontal areas activated and the correlational patterns

  12. Central as well as Peripheral Attentional Bottlenecks in Dual-Task Performance Activate Lateral Prefrontal Cortices.

    PubMed

    Szameitat, André J; Vanloo, Azonya; Müller, Hermann J

    2016-01-01

    Human information processing suffers from severe limitations in parallel processing. In particular, when required to respond to two stimuli in rapid succession, processing bottlenecks may appear at central and peripheral stages of task processing. Importantly, it has been suggested that executive functions are needed to resolve the interference arising at such bottlenecks. The aims of the present study were to test whether central attentional limitations (i.e., bottleneck at the decisional response selection stage) as well as peripheral limitations (i.e., bottleneck at response initiation) both demand executive functions located in the lateral prefrontal cortex. For this, we re-analyzed two previous studies, in which a total of 33 participants performed a dual-task according to the paradigm of the psychological refractory period (PRP) during functional magnetic resonance imaging (fMRI). In one study (N = 17), the PRP task consisted of two two-choice response tasks known to suffer from a central bottleneck (CB group). In the other study (N = 16), the PRP task consisted of two simple-response tasks known to suffer from a peripheral bottleneck (PB group). Both groups showed considerable dual-task costs in form of slowing of the second response in the dual-task (PRP effect). Imaging results are based on the subtraction of both single-tasks from the dual-task within each group. In the CB group, the bilateral middle frontal gyri and inferior frontal gyri were activated. Higher activation in these areas was associated with lower dual-task costs. In the PB group, the right middle frontal and inferior frontal gyrus (IFG) were activated. Here, higher activation was associated with higher dual-task costs. In conclusion we suggest that central and peripheral bottlenecks both demand executive functions located in lateral prefrontal cortices (LPFC). Differences between the CB and PB groups with respect to the exact prefrontal areas activated and the correlational patterns

  13. Perceptual demand modulates activation of human auditory cortex in response to task-irrelevant sounds.

    PubMed

    Sabri, Merav; Humphries, Colin; Verber, Matthew; Mangalathu, Jain; Desai, Anjali; Binder, Jeffrey R; Liebenthal, Einat

    2013-09-01

    In the visual modality, perceptual demand on a goal-directed task has been shown to modulate the extent to which irrelevant information can be disregarded at a sensory-perceptual stage of processing. In the auditory modality, the effect of perceptual demand on neural representations of task-irrelevant sounds is unclear. We compared simultaneous ERPs and fMRI responses associated with task-irrelevant sounds across parametrically modulated perceptual task demands in a dichotic-listening paradigm. Participants performed a signal detection task in one ear (Attend ear) while ignoring task-irrelevant syllable sounds in the other ear (Ignore ear). Results revealed modulation of syllable processing by auditory perceptual demand in an ROI in middle left superior temporal gyrus and in negative ERP activity 130-230 msec post stimulus onset. Increasing the perceptual demand in the Attend ear was associated with a reduced neural response in both fMRI and ERP to task-irrelevant sounds. These findings are in support of a selection model whereby ongoing perceptual demands modulate task-irrelevant sound processing in auditory cortex.

  14. Embodied simulation as part of affective evaluation processes: task dependence of valence concordant EMG activity.

    PubMed

    Weinreich, André; Funcke, Jakob Maria

    2014-01-01

    Drawing on recent findings, this study examines whether valence concordant electromyography (EMG) responses can be explained as an unconditional effect of mere stimulus processing or as somatosensory simulation driven by task-dependent processing strategies. While facial EMG over the Corrugator supercilii and the Zygomaticus major was measured, each participant performed two tasks with pictures of album covers. One task was an affective evaluation task and the other was to attribute the album covers to one of five decades. The Embodied Emotion Account predicts that valence concordant EMG is more likely to occur if the task necessitates a somatosensory simulation of the evaluative meaning of stimuli. Results support this prediction with regard to Corrugator supercilii in that valence concordant EMG activity was only present in the affective evaluation task but not in the non-evaluative task. Results for the Zygomaticus major were ambiguous. Our findings are in line with the view that EMG activity is an embodied part of the evaluation process and not a mere physical outcome.

  15. Game-like tasks for comparative research: leveling the playing field

    NASA Technical Reports Server (NTRS)

    Washburn, D. A.; Gulledge, J. P.; Rumbaugh, D. M. (Principal Investigator)

    1995-01-01

    Game-like computer tasks offer many benefits for psychological research. In this paper, the usefulness of such tasks to bridge population differences (e.g., age, intelligence, species) is discussed and illustrated. A task called ALVIN was used to assess humans' and monkeys' working memory for sequences of colors with or without tones. Humans repeated longer lists than did the monkeys, and only humans benefited when the visual stimuli were accompanied by auditory cues. However, the monkeys did recall sequences at levels comparable to those reported elsewhere for children. Comparison of similarities and differences between the species is possible because the two groups were tested with exactly the same game-like paradigm.

  16. Sour gas plant remediation technology research and demonstration project, Task 7.53. Topical report, January--December 1993

    SciTech Connect

    Stepan, D.J.; Kuehnel, V.; Schmit, C.R.

    1994-02-01

    Recognizing the potential impacts of sour gas plant operations on the subsurface environment, the Canadian Association of Petroleum Producers (CAPP) and Environment Canada initiated a multiphase study focusing on research related to the development and demonstration of remedial technologies for soil and groundwater contamination at these facilities. Research performed under this project was designed to supplement and be coordinated with research activities being conducted at an operational sour gas plant located in Rocky Mountain House, Alberta, Canada. These research tasks included hydrogeological site characterization, subsurface contaminant characterization, ex situ treatment of groundwater, and subsurface remediation of residual contamination in the unsaturated zone. Ex situ treatment of groundwater included evaluations of air stripping, steam stripping, advanced oxidation, and biological treatment, as well as the development of an artificial freeze crystallization process. Soil vapor extraction was evaluated as a technique to address residual contamination in the unsaturated zone.

  17. Dissociating sentential prosody from sentence processing: activation interacts with task demands.

    PubMed

    Plante, Elena; Creusere, Marlena; Sabin, Cynthia

    2002-09-01

    Sentence processing was contrasted with processing of syntactic prosody under two task conditions in order to examine the representation of these components of language and their interaction with working memory load. Twelve adults received fMDI scans while they listened to low-pass filtered and unfiltered sentences either passively, or during tasks that required subjects to remember and recognize information contained in the stimuli. Results indicated that temporal activation for prosodic stimuli differed compared to activation for sentence stimuli only during passive listening tasks. The inclusion of memory demands was associated with frontal activation, which was differentially lateralized for sentence and prosodic stimuli. The results demonstrate differential brain activation for prosodic vs sentential stimuli which interacts with the memory demands placed on the subjects.

  18. Stability and variability: indicators for passive stability and active control in a rhythmic task.

    PubMed

    Wei, Kunlin; Dijkstra, Tjeerd M H; Sternad, Dagmar

    2008-06-01

    Using a rhythmic task where human subjects bounced a ball with a handheld racket, fine-grained analyses of stability and variability extricated contributions from open-loop control, noise strength, and active error compensation. Based on stability analyses of a stochastic-deterministic model of the task--a surface contacting the ball by periodic movements--open-loop or dynamic stability was assessed by the acceleration of the racket at contact. Autocovariance analyses of model and data were further used to gauge the contributions of open-loop stability and noise strength. Variability and regression analyses estimated active error compensation. Empirical results demonstrated that experienced actors exploited open-loop stability more than novices, had lower noise strength, and applied more active error compensations. By manipulating the model parameter coefficient of restitution, task stability was varied and showed that actors graded these three components as a function of task stability. It is concluded that actors tune into task stability when stability is high but use more active compensation when stability is reduced. Implications for the neural underpinnings for passive stability and active control are discussed. Further, results showed that stability and variability are not simply the inverse of each other but contain more quantitative information when combined with model analyses.

  19. Performance-Related Activity in Medial Rostral Prefrontal Cortex (Area 10) during Low-Demand Tasks

    ERIC Educational Resources Information Center

    Gilbert, Sam J.; Simons, Jon S.; Frith, Christopher D.; Burgess, Paul W.

    2006-01-01

    Neuroimaging studies have frequently observed relatively high activity in medial rostral prefrontal cortex (PFC) during rest or baseline conditions. Some accounts have attributed this high activity to the occurrence of unconstrained stimulus-independent and task-unrelated thought processes during baseline conditions. Here, the authors investigated…

  20. Spatio-temporal analysis reveals active control of both task-relevant and task-irrelevant variables

    PubMed Central

    Rácz, Kornelius; Valero-Cuevas, Francisco J.

    2013-01-01

    The Uncontrolled Manifold (UCM) hypothesis and Minimal Intervention principle propose that the observed differential variability across task relevant (i.e., task goals) vs. irrelevant (i.e., in the null space of those goals) variables is evidence of a separation of task variables for efficient neural control, ranked by their respective variabilities (sometimes referred to as hierarchy of control). Support for this comes from spatial domain analyses (i.e., structure of) of kinematic, kinetic, and EMG variability. While proponents admit the possibility of preferential as opposed to strictly uncontrolled variables, such distinctions have only begun to be quantified or considered in the temporal domain when inferring control action. Here we extend the study of task variability during tripod static grasp to the temporal domain by applying diffusion analysis. We show that both task-relevant and task-irrelevant parameters show corrective action at some time scales; and conversely, that task-relevant parameters do not show corrective action at other time scales. That is, the spatial fluctuations of fingertip forces show, as expected, greater ranges of variability in task-irrelevant variables (>98% associated with changes in total grasp force; vs. only <2% in task-relevant changes associated with acceleration of the object). But at some time scales, however, temporal fluctuations of task-irrelevant variables exhibit negative correlations clearly indicative of corrective action (scaling exponents <0.5); and temporal fluctuations of task-relevant variables exhibit neutral and positive correlations clearly indicative of absence of corrective action (scaling exponents ≥0.5). In agreement with recent work in other behavioral contexts, these results propose we revise our understanding of variability vis-á-vis task relevance by considering both spatial and temporal features of all task variables when inferring control action and understanding how the CNS confronts task

  1. Research Priorities and Plans for the International Space Station - Results of the REMAP Task Force

    NASA Astrophysics Data System (ADS)

    Kicza, M.

    2002-01-01

    Recent events in the International Space Station (ISS) Program have resulted in the necessity to re-examine the research priorities and research plans for future years. Due to both technical and fiscal resource constraints expected on the International Space Station, it is imperative that research priorities be carefully reviewed and clearly articulated. The U.S. President's Budget language for 2003 states that "...NASA will be working with the White House Office of Science and Technology Policy (OSTP) to engage the scientific community and establish clear high-priority, affordable science objectives with near-term focus on improving scientific productivity. The results of this review will help set the science agenda for Biological and Physical Research that will in turn define how the Space Station is used." In consultation with OSTP and the Office of Management and budget (OMB), NASA's Office of Biological and Physical Research (OBPR) is assembling an ad-hoc external advisory committee, the Biological and Physical REsearch MAximization and Prioritization (REMAP) Task Force, which will be under the auspices of the NASA Advisory Council. This paper will describe the outcome of the Task Force and how it will be used to define a roadmap for near and long term Biological and Physical Research objectives. Additionally the paper will discuss the maximization of the International Space Station utilization.

  2. Research priorities and plans for the International Space Station-results of the 'REMAP' Task Force

    NASA Technical Reports Server (NTRS)

    Kicza, M.; Erickson, K.; Trinh, E.

    2003-01-01

    Recent events in the International Space Station (ISS) Program have resulted in the necessity to re-examine the research priorities and research plans for future years. Due to both technical and fiscal resource constraints expected on the International Space Station, it is imperative that research priorities be carefully reviewed and clearly articulated. In consultation with OSTP and the Office of Management and budget (OMB), NASA's Office of Biological and Physical Research (OBPR) assembled an ad-hoc external advisory committee, the Biological and Physical Research Maximization and Prioritization (REMAP) Task Force. This paper describes the outcome of the Task Force and how it is being used to define a roadmap for near and long-term Biological and Physical Research objectives that supports NASA's Vision and Mission. Additionally, the paper discusses further prioritizations that were necessitated by budget and ISS resource constraints in order to maximize utilization of the International Space Station. Finally, a process has been developed to integrate the requirements for this prioritized research with other agency requirements to develop an integrated ISS assembly and utilization plan that maximizes scientific output. c2003 American Institute of Aeronautics and Astronautics. Published by Elsevier Science Ltd. All rights reserved.

  3. Research priorities and plans for the International Space Station-results of the 'REMAP' Task Force.

    PubMed

    Kicza, M; Erickson, K; Trinh, E

    2003-01-01

    Recent events in the International Space Station (ISS) Program have resulted in the necessity to re-examine the research priorities and research plans for future years. Due to both technical and fiscal resource constraints expected on the International Space Station, it is imperative that research priorities be carefully reviewed and clearly articulated. In consultation with OSTP and the Office of Management and budget (OMB), NASA's Office of Biological and Physical Research (OBPR) assembled an ad-hoc external advisory committee, the Biological and Physical Research Maximization and Prioritization (REMAP) Task Force. This paper describes the outcome of the Task Force and how it is being used to define a roadmap for near and long-term Biological and Physical Research objectives that supports NASA's Vision and Mission. Additionally, the paper discusses further prioritizations that were necessitated by budget and ISS resource constraints in order to maximize utilization of the International Space Station. Finally, a process has been developed to integrate the requirements for this prioritized research with other agency requirements to develop an integrated ISS assembly and utilization plan that maximizes scientific output.

  4. Age-related shifts in brain activity dynamics during task switching.

    PubMed

    Jimura, Koji; Braver, Todd S

    2010-06-01

    Cognitive aging studies have suggested that older adults show declines in both sustained and transient cognitive control processes. However, previous neuroimaging studies have primarily focused on age-related change in the magnitude, but not temporal dynamics, of brain activity. The present study compared brain activity dynamics in healthy old and young adults during task switching. A mixed blocked/event-related functional magnetic resonance imaging design enabled separation of transient and sustained neural activity associated with cognitive control. Relative to young adults, older adults exhibited not only decreased sustained activity in the anterior prefrontal cortex (aPFC) during task-switching blocks but also increased transient activity on task-switch trials. Another pattern of age-related shift in dynamics was present in the lateral PFC (lPFC) and posterior parietal cortex (PPC), with younger adults showing a cue-related response during task-switch trials in lPFC and PPC, whereas older adults exhibited switch-related activation during the cue period in PPC only. In all 3 regions, these qualitatively distinct patterns of brain activity predicted qualitatively distinct patterns of behavioral performance across the 2 age groups. Together, these results suggest that older adults may shift from a proactive to reactive cognitive control strategy as a means of retaining relatively preserved behavioral performance in the face of age-related neurocognitive changes. PMID:19805420

  5. Subjective Significance Shapes Arousal Effects on Modified Stroop Task Performance: A Duality of Activation Mechanisms Account.

    PubMed

    Imbir, Kamil K

    2016-01-01

    Activation mechanisms such as arousal are known to be responsible for slowdown observed in the Emotional Stroop and modified Stroop tasks. Using the duality of mind perspective, we may conclude that both ways of processing information (automatic or controlled) should have their own mechanisms of activation, namely, arousal for an experiential mind, and subjective significance for a rational mind. To investigate the consequences of both, factorial manipulation was prepared. Other factors that influence Stroop task processing such as valence, concreteness, frequency, and word length were controlled. Subjective significance was expected to influence arousal effects. In the first study, the task was to name the color of font for activation charged words. In the second study, activation charged words were, at the same time, combined with an incongruent condition of the classical Stroop task around a fixation point. The task was to indicate the font color for color-meaning words. In both studies, subjective significance was found to shape the arousal impact on performance in terms of the slowdown reduction for words charged with subjective significance. PMID:26869974

  6. Toward the Development of Cognitive Task Difficulty Metrics to Support Intelligence Analysis Research

    SciTech Connect

    Greitzer, Frank L.

    2005-08-08

    Intelligence analysis is a cognitively complex task that is the subject of considerable research aimed at developing methods and tools to aid the analysis process. To support such research, it is necessary to characterize the difficulty or complexity of intelligence analysis tasks in order to facilitate assessments of the impact or effectiveness of tools that are being considered for deployment. A number of informal accounts of ''What makes intelligence analysis hard'' are available, but there has been no attempt to establish a more rigorous characterization with well-defined difficulty factors or dimensions. This paper takes an initial step in this direction by describing a set of proposed difficulty metrics based on cognitive principles.

  7. Effects of reaction time variability and age on brain activity during Stroop task performance.

    PubMed

    Tam, Angela; Luedke, Angela C; Walsh, Jeremy J; Fernandez-Ruiz, Juan; Garcia, Angeles

    2015-09-01

    Variability in reaction time during task performance may reflect fluctuations in attention and cause reduced performance in goal-directed tasks, yet it is unclear whether the mechanisms behind this phenomenon change with age. Using fMRI, we tested young and cognitively healthy older adults with the Stroop task to determine whether aging affects the neural mechanisms underlying intra-individual reaction time variability. We found significant between-group differences in BOLD activity modulated by reaction time. In older adults, longer reaction times were associated with greater activity in frontoparietal attentional areas, while in younger adults longer reaction times were associated with greater activity in default mode network areas. Our results suggest that the neural correlates of reaction time variability change with healthy aging, reinforcing the concept of functional plasticity to maintain high cognitive function throughout the lifespan.

  8. Investigating the correlation between the neural activity and task performance in a psychomotor vigilance test.

    PubMed

    Hu, Zhongze; Sun, Yu; Lim, Julian; Thakor, Nitish; Bezerianos, Anastasios

    2015-01-01

    Neural activity is known to correlate with decrements in task performance as individuals enter the state of mental fatigue which might lead to lowered productivity and increased safety risks. Incorporating a passive brain computer interface (BCI) technique that detects changes in subject's neural activity and predicts the behavioral performance when the subject is underperforming might be a promising approach to reduce human error in real-world situations. Here, we developed a reliable model using EEG power spectrum to estimate time-on-task performance in a psychomotor vigilance test (PVT) which can fit across individuals. High correlation between the estimated and actual reaction time was achieved. Hence, our results illustrate the feasibility for modeling time-on-task decrements in performance among different individuals from their brainwave activity, with potential applications in several domains, including traffic and industrial safety. PMID:26737349

  9. Designing Probabilistic Tasks for Kindergartners

    ERIC Educational Resources Information Center

    Skoumpourdi, Chrysanthi; Kafoussi, Sonia; Tatsis, Konstantinos

    2009-01-01

    Recent research suggests that children could be engaged in probability tasks at an early age and task characteristics seem to play an important role in the way children perceive an activity. To this direction in the present article we investigate the role of some basic characteristics of probabilistic tasks in their design and implementation. In…

  10. TASK DIFFICULTY MODULATES ACTIVITY OF SPECIFIC NEURONAL POPULATIONS IN PRIMARY VISUAL CORTEX

    PubMed Central

    Chen, Yao; Martinez-Conde, Susana; Macknik, Stephen L.; Bereshpolova, Yulia; Swadlow, Harvey A.; Alonso, Jose-Manuel

    2008-01-01

    Spatial attention enhances our ability to detect stimuli at restricted regions of the visual field. This enhancement is thought to depend on the difficulty of the task being performed, but the underlying neuronal mechanisms for this dependency remain largely unknown. Here we demonstrate that task difficulty modulates neuronal firing rate at the earliest stages of cortical visual processing (area V1) in the macaque monkey. These modulations are spatially specific: increasing task difficulty enhances V1 neuronal firing rate at the focus of attention and suppresses it in regions surrounding the focus. Moreover, we show that response enhancement and suppression are mediated by distinct populations of neurons that differ in direction selectivity, spike width, interspike interval distribution and contrast sensitivity. Our results provide strong support for center-surround models of spatial attention and suggest that task difficulty modulates the activity of specific populations of neurons in the primary visual cortex. PMID:18604204

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

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

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

  12. A research program in neutrino physics, cosmic rays and elementary particles. Progress report for Task A

    SciTech Connect

    Reines, F.; Sobel, H.W.

    1991-08-01

    Physics interests of the group are focused primarily on tests of conservation laws and studies of fundamental interactions between particles. There is also a significant interest in astrophysics and cosmic rays. Task A consists of three experimental programs; a Double-Beta Decay study (currently at the Hoover Dam), a Reactor Neutrino program (until this year at Savannah River), and the IMB Proton Decay experiment in a Cleveland salt mine. Discussion of the research in each area is given.

  13. 77 FR 76000 - Notice of Availability of Draft Report of the NOAA Research and Development Portfolio Review Task...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-26

    ... Availability of Draft Report of the NOAA Research and Development Portfolio Review Task Force and Request for... draft report of the SAB Research and Development Portfolio Review Task Force (PRTF) for public comment.../ SAB, Silver Spring, Maryland 20910. FOR FURTHER INFORMATION CONTACT: Dr. Cynthia Decker,...

  14. Associations between prefrontal cortex activation and H-reflex modulation during dual task gait

    PubMed Central

    Meester, Daan; Al-Yahya, Emad; Dawes, Helen; Martin-Fagg, Penny; Piñon, Carmen

    2014-01-01

    Walking, although a largely automatic process, is controlled by the cortex and the spinal cord with corrective reflexes modulated through integration of neural signals from central and peripheral inputs at supraspinal level throughout the gait cycle. In this study we used an additional cognitive task to interfere with the automatic processing during walking in order to explore the neural mechanisms involved in healthy young adults. Participants were asked to walk on a treadmill at two speeds, both with and without additional cognitive load. We evaluated the impact of speed and cognitive load by analyzing activity of the prefrontal cortex (PFC) using functional Near-Infrared Spectroscopy (fNIRS) alongside spinal cord reflex activity measured by soleus H-reflex amplitude and gait changes obtained by using an inertial measuring unit. Repeated measures ANOVA revealed that fNIRS Oxy-Hb concentrations significantly increased in the PFC with dual task (walking while performing a cognitive task) compared to a single task (walking only; p < 0.05). PFC activity was unaffected by increases of walking speed. H-reflex amplitude and gait variables did not change in response to either dual task or increases in walking speed. When walking under additional cognitive load participants adapted by using greater activity in the PFC, but this adaptation did not detrimentally affect H-reflex amplitude or gait variables. Our findings suggest that in a healthy young population central mechanisms (PFC) are activated in response to cognitive loads but that H-reflex activity and gait performance can successfully be maintained. This study provides insights into the mechanisms behind healthy individuals safely performing dual task walking. PMID:24600375

  15. Noise power associated with decreased task-induced variability of brain electrical activity in schizophrenia.

    PubMed

    Molina, Vicente; Bachiller, Alejandro; Suazo, Vanessa; Lubeiro, Alba; Poza, Jesús; Hornero, Roberto

    2016-02-01

    In schizophrenia, both increased baseline metabolic and electroencephalographic (EEG) activities as well as decreased task-related modulation of neural dynamics have been reported. Noise power (NP) can measure the background EEG activity during task performance, and Shannon entropy (SE) is useful for quantifying the global modulation of EEG activity with a high temporal resolution. In this study, we have assessed the possible relationship between increased NP in theta and gamma bands and decreased SE modulation in 24 patients with schizophrenia and 26 controls over the parietal and central regions during a P300 task. SE modulation was calculated as the change from baseline to the active epoch (i.e., 150-550 ms following the target stimulus onset). Patients with schizophrenia displayed statistically significant higher NP values and lower SE modulation than healthy controls. We found a significant association between gamma NP and SE in all of the participants. Specifically, a NP increase in the gamma band was followed by a decrease in SE change. These results support the notion that an excess of gamma activity, unlocked to the task being performed, is accompanied by a decreased modulation of EEG activity in schizophrenia.

  16. Neural correlates of executive dysfunction in schizophrenia: failure to modulate brain activity with task demands.

    PubMed

    Dirnberger, Georg; Fuller, Rebecca; Frith, Chris; Jahanshahi, Marjan

    2014-11-12

    In schizophrenia, executive functions are impaired and are associated with altered activation of prefrontal areas. We used H2[15]O PET to examine patients with schizophrenia and matched controls on a random number generation (RNG) task and a control counting (COUNT) task. To assess the effects of increasing task demand, both tasks were performed at three different rates (intervals 1, 2 or 3 s). Both groups showed a significant increase in the nonrandomness of responses at faster rates of RNG. Despite similar performances, patients but not controls showed higher activation of the right dorsolateral prefrontal cortex (DLPFC) and atypically reduced activation of the right anterior cingulate gyrus and the right medial frontal gyrus in RNG compared with COUNT, whereas only for controls, activation of the left DLPFC was increased and activation of the right superior temporal gyrus and the right superior frontal gyrus was reduced in the same comparison. Whereas for the controls several cortical areas including the bilateral superior temporal gyrus and the bilateral DLPFC, together with the right cerebellum, showed significant changes in regional cerebral blood flow with faster or slower rates, patients with schizophrenia showed rate-dependent changes only in the left cerebellum. In conclusion, the patients' failure to modulate cortical activation with changing demands of rate, particularly in prefrontal areas and in the cerebellum, and even when performance is similar to that in healthy controls, is a characteristic of their abnormal pattern of executive processing. PMID:25275638

  17. Effects of feedback on activation of the quadriceps during weight-bearing tasks of the Wii

    PubMed Central

    Fernandes da Silva, Fabiano; Aparecido de Souza, Renato; Dias, Eric Fernandes; Silveira, Landulfo; Villaverde, Antonio Balbin

    2015-01-01

    [Purpose] This investigation evaluated the effect of real-time feedback on electrical activation of the quadriceps during 3 weight-bearing tasks of the Wii Fit Plus®. [Subjects] Thirty male healthy volunteers were recruited. [Methods] Activation of the vastus medialis, vastus lateralis, and rectus femoris muscles was recorded during virtual lunge, single leg extension, and single leg reach exercises. Each exercise was performed twice in 3 randomized experimental conditions (with visual feedback, with auditory feedback, and with no feedback). The normalized electromyographic data (using maximum voluntary isometric contraction) were analyzed using repeated measures analysis of variance and Tukey’s test. [Results] No significant difference was found in the muscles among the feedback conditions during the 3 exercises. However, the variation in the muscle activity of the vastus medialis and vastus lateralis (18.23–29.20% of maximum voluntary isometric contraction) was higher (47–62%) than that in the rectus femoris (7.35–12.98% of maximum voluntary isometric contraction). [Conclusion] Real-time feedback did not alter quadriceps activation during the Wii tasks. Additionally, these games showed electromyographic activation levels similar to those for the same tasks outside the virtual environment. The Wii weight-bearing tasks could therefore constitute a physical activity program but without the additional benefit of feedback. PMID:26180301

  18. Effects of feedback on activation of the quadriceps during weight-bearing tasks of the Wii.

    PubMed

    Fernandes da Silva, Fabiano; Aparecido de Souza, Renato; Dias, Eric Fernandes; Silveira, Landulfo; Villaverde, Antonio Balbin

    2015-06-01

    [Purpose] This investigation evaluated the effect of real-time feedback on electrical activation of the quadriceps during 3 weight-bearing tasks of the Wii Fit Plus(®). [Subjects] Thirty male healthy volunteers were recruited. [Methods] Activation of the vastus medialis, vastus lateralis, and rectus femoris muscles was recorded during virtual lunge, single leg extension, and single leg reach exercises. Each exercise was performed twice in 3 randomized experimental conditions (with visual feedback, with auditory feedback, and with no feedback). The normalized electromyographic data (using maximum voluntary isometric contraction) were analyzed using repeated measures analysis of variance and Tukey's test. [Results] No significant difference was found in the muscles among the feedback conditions during the 3 exercises. However, the variation in the muscle activity of the vastus medialis and vastus lateralis (18.23-29.20% of maximum voluntary isometric contraction) was higher (47-62%) than that in the rectus femoris (7.35-12.98% of maximum voluntary isometric contraction). [Conclusion] Real-time feedback did not alter quadriceps activation during the Wii tasks. Additionally, these games showed electromyographic activation levels similar to those for the same tasks outside the virtual environment. The Wii weight-bearing tasks could therefore constitute a physical activity program but without the additional benefit of feedback.

  19. Task-Driven Activity Reduces the Cortical Activity Space of the Brain: Experiment and Whole-Brain Modeling

    PubMed Central

    Hagmann, Patric; Deco, Gustavo

    2015-01-01

    How a stimulus or a task alters the spontaneous dynamics of the brain remains a fundamental open question in neuroscience. One of the most robust hallmarks of task/stimulus-driven brain dynamics is the decrease of variability with respect to the spontaneous level, an effect seen across multiple experimental conditions and in brain signals observed at different spatiotemporal scales. Recently, it was observed that the trial-to-trial variability and temporal variance of functional magnetic resonance imaging (fMRI) signals decrease in the task-driven activity. Here we examined the dynamics of a large-scale model of the human cortex to provide a mechanistic understanding of these observations. The model allows computing the statistics of synaptic activity in the spontaneous condition and in putative tasks determined by external inputs to a given subset of brain regions. We demonstrated that external inputs decrease the variance, increase the covariances, and decrease the autocovariance of synaptic activity as a consequence of single node and large-scale network dynamics. Altogether, these changes in network statistics imply a reduction of entropy, meaning that the spontaneous synaptic activity outlines a larger multidimensional activity space than does the task-driven activity. We tested this model’s prediction on fMRI signals from healthy humans acquired during rest and task conditions and found a significant decrease of entropy in the stimulus-driven activity. Altogether, our study proposes a mechanism for increasing the information capacity of brain networks by enlarging the volume of possible activity configurations at rest and reliably settling into a confined stimulus-driven state to allow better transmission of stimulus-related information. PMID:26317432

  20. Task-Driven Activity Reduces the Cortical Activity Space of the Brain: Experiment and Whole-Brain Modeling.

    PubMed

    Ponce-Alvarez, Adrián; He, Biyu J; Hagmann, Patric; Deco, Gustavo

    2015-08-01

    How a stimulus or a task alters the spontaneous dynamics of the brain remains a fundamental open question in neuroscience. One of the most robust hallmarks of task/stimulus-driven brain dynamics is the decrease of variability with respect to the spontaneous level, an effect seen across multiple experimental conditions and in brain signals observed at different spatiotemporal scales. Recently, it was observed that the trial-to-trial variability and temporal variance of functional magnetic resonance imaging (fMRI) signals decrease in the task-driven activity. Here we examined the dynamics of a large-scale model of the human cortex to provide a mechanistic understanding of these observations. The model allows computing the statistics of synaptic activity in the spontaneous condition and in putative tasks determined by external inputs to a given subset of brain regions. We demonstrated that external inputs decrease the variance, increase the covariances, and decrease the autocovariance of synaptic activity as a consequence of single node and large-scale network dynamics. Altogether, these changes in network statistics imply a reduction of entropy, meaning that the spontaneous synaptic activity outlines a larger multidimensional activity space than does the task-driven activity. We tested this model's prediction on fMRI signals from healthy humans acquired during rest and task conditions and found a significant decrease of entropy in the stimulus-driven activity. Altogether, our study proposes a mechanism for increasing the information capacity of brain networks by enlarging the volume of possible activity configurations at rest and reliably settling into a confined stimulus-driven state to allow better transmission of stimulus-related information.

  1. Environmental research on a modified in situ oil shale task process. Progress report

    SciTech Connect

    Not Available

    1980-05-01

    This report summarizes the progress of the US Department of Energy's Oil Shale Task Force in its research program at the Occidental Oil Shale, Inc. facility at Logan Wash, Colorado. More specifically, the Task Force obtained samples from Retort 3E and Retort 6 and submitted these samples to a variety of analyses. The samples collected included: crude oil (Retort 6); light oil (Retort 6); product water (Retort 6); boiler blowdown (Retort 6); makeup water (Retort 6); mine sump water; groundwater; water from Retorts 1 through 5; retort gas (Retort 6); mine air; mine dust; and spent shale core (Retort 3E). The locations of the sampling points and methods used for collection and storage are discussed in Chapter 2 (Characterization). These samples were then distributed to the various laboratories and universities participating in the Task Force. For convenience in organizing the data, it is useful to group the work into three categories: Characterization, Leaching, and Health Effects. While many samples still have not been analyzed and much of the data remains to be interpreted, there are some preliminary conclusions the Task Force feels will be helpful in defining future needs and establishing priorities. It is important to note that drilling agents other than water were used in the recovery of the core from Retort 3E. These agents have been analyzed (see Table 12 in Chapter 2) for several constituents of interest. As a result some of the analyses of this core sample and leachates must be considered tentative.

  2. Dizocilpine (MK-801) impairs learning in the active place avoidance task but has no effect on the performance during task/context alternation.

    PubMed

    Vojtechova, Iveta; Petrasek, Tomas; Hatalova, Hana; Pistikova, Adela; Vales, Karel; Stuchlik, Ales

    2016-05-15

    The prevention of engram interference, pattern separation, flexibility, cognitive coordination and spatial navigation are usually studied separately at the behavioral level. Impairment in executive functions is often observed in patients suffering from schizophrenia. We have designed a protocol for assessing these functions all together as behavioral separation. This protocol is based on alternated or sequential training in two tasks testing different hippocampal functions (the Morris water maze and active place avoidance), and alternated or sequential training in two similar environments of the active place avoidance task. In Experiment 1, we tested, in adult rats, whether the performance in two different spatial tasks was affected by their order in sequential learning, or by their day-to-day alternation. In Experiment 2, rats learned to solve the active place avoidance task in two environments either alternately or sequentially. We found that rats are able to acquire both tasks and to discriminate both similar contexts without obvious problems regardless of the order or the alternation. We used two groups of rats, controls and a rat model of psychosis induced by a subchronic intraperitoneal application of 0.08mg/kg of dizocilpine (MK-801), a non-competitive antagonist of NMDA receptors. Dizocilpine had no selective effect on parallel/sequential learning of tasks/contexts. However, it caused hyperlocomotion and a significant deficit in learning in the active place avoidance task regardless of the task alternation. Cognitive coordination tested by this task is probably more sensitive to dizocilpine than spatial orientation because no hyperactivity or learning impairment was observed in the Morris water maze.

  3. Effect of Mild Thyrotoxicosis on Performance and Brain Activations in a Working Memory Task

    PubMed Central

    Göbel, Anna; Heldmann, Marcus; Göttlich, Martin; Dirk, Anna-Luise; Brabant, Georg; Münte, Thomas F.

    2016-01-01

    Aims Disturbed levels of thyroid hormones are associated with neuropsychiatric disorders, including memory impairments. The aim of this study was to evaluate effects of mild induced thyrotoxicosis on working memory and its neural correlates. Methods Twenty-nine healthy, male subjects with normal thyroid state participated in the study. Functional MRI was acquired during a working memory task (n-back task) before and after ingesting 250 μg L-thyroxin per day for a period of eight weeks. In addition, neuropsychological tests were performed. Results In the hyperthyroid condition the subjects showed slower reaction times, but a higher accuracy in the 0-back version of the memory tasks. Fewer differences between euthyroid and hyperthyroid state were seen for the more difficult conditions of the n-back task. FMRI revealed effects of difficulty in the parahippocampal gyrus, supplementary motor area, prefrontal cortex, anterior cingulate cortex, posterior cerebellum, rolandic operculum and insula (p<0.05, FWE corrected). When comparing euthyroid and hyperthyroid condition in relation to task-induced activation, differences of activation were found in the right prefrontal cortex as well as in the right parahippocampal area. In the psychological assessment, the alerting effect in the Attention Network Task (ANT) and four out of five parameters of the auditory verbal learning test (AVLT) showed an increase from euthyroid to hyperthyroid state. Conclusions It can be concluded that even a short-term intake of thyroid hormones leads to an activation of brain areas associated with working memory and to an improvement of accuracy of working memory tasks. PMID:27536945

  4. Task Control Signals in Pediatric Tourette Syndrome Show Evidence of Immature and Anomalous Functional Activity

    PubMed Central

    Church, Jessica A.; Wenger, Kristin K.; Dosenbach, Nico U. F.; Miezin, Francis M.; Petersen, Steven E.; Schlaggar, Bradley L.

    2009-01-01

    Tourette Syndrome (TS) is a pediatric movement disorder that may affect control signaling in the brain. Previous work has proposed a dual-networks architecture of control processing involving a task-maintenance network and an adaptive control network (Dosenbach et al., 2008). A prior resting-state functional connectivity MRI (rs-fcMRI) analysis in TS has revealed functional immaturity in both putative control networks, with “anomalous” correlations (i.e., correlations outside the typical developmental range) limited to the adaptive control network (Church et al., 2009). The present study used functional MRI (fMRI) to study brain activity related to adaptive control (by studying start-cues signals), and to task-maintenance (by studying signals sustained across a task set). Two hypotheses from the previous rs-fcMRI results were tested. First, adaptive control (i.e., start-cue) activity will be altered in TS, including activity inconsistent with typical development (“anomalous”). Second, group differences found in task-maintenance (i.e., sustained) activity will be consistent with functional immaturity in TS. We examined regions found through a direct comparison of adolescents with and without TS, as well as regions derived from a previous investigation that showed differences between unaffected children and adults. The TS group showed decreased start-cue signal magnitude in regions where start-cue activity is unchanged over typical development, consistent with anomalous adaptive control. The TS group also had higher magnitude sustained signals in frontal cortex regions that overlapped with regions showing differences over typical development, consistent with immature task-maintenance in TS. The results demonstrate task-related fMRI signal differences anticipated by the atypical functional connectivity found previously in adolescents with TS, strengthening the evidence for functional immaturity and anomalous signaling in control networks in adolescents with TS

  5. The Association Between Eye Movements and Cerebellar Activation in a Verbal Working Memory Task.

    PubMed

    Peterburs, Jutta; Cheng, Dominic T; Desmond, John E

    2016-09-01

    It has been argued that cerebellar activations during cognitive tasks may masquerade as cognition, while actually reflecting processes related to movement planning or motor learning. The present study investigated whether the cerebellar load effect for verbal working memory, that is, increased activations in lobule VI/Crus I and lobule VIIB/VIIIA, is related to eye movements and oculomotor processing. Fifteen participants performed an fMRI-based Sternberg verbal working memory task. Oculomotor and cognitive task demands were manipulated by using closely and widely spaced stimuli, and high and low cognitive load. Trial-based quantitative eye movement parameters were obtained from concurrent eye tracking. Conventional MRI analysis replicated the cerebellar load effect in lobules VI and VIIB/VIIIa. With quantitative eye movement parameters as regressors, analysis yielded very similar activation patterns. While load effect and eye regressor generally recruited spatially distinct neocortical and cerebellar regions, conjunction analysis showed that a small subset of prefrontal areas implicated in the load effect also responded to the eye regressor. The present results indicate that cognitive load-dependent activations in lateral superior and posteroinferior cerebellar regions in the Sternberg task are independent of eye movements occurring during stimulus encoding. This is inconsistent with the notion that cognitive load-dependent cerebellar activations merely reflect oculomotor processing. PMID:26286918

  6. Automated Visual Cognitive Tasks for Recording Neural Activity Using a Floor Projection Maze

    PubMed Central

    Kent, Brendon W.; Yang, Fang-Chi; Burwell, Rebecca D.

    2014-01-01

    Neuropsychological tasks used in primates to investigate mechanisms of learning and memory are typically visually guided cognitive tasks. We have developed visual cognitive tasks for rats using the Floor Projection Maze1,2 that are optimized for visual abilities of rats permitting stronger comparisons of experimental findings with other species. In order to investigate neural correlates of learning and memory, we have integrated electrophysiological recordings into fully automated cognitive tasks on the Floor Projection Maze1,2. Behavioral software interfaced with an animal tracking system allows monitoring of the animal's behavior with precise control of image presentation and reward contingencies for better trained animals. Integration with an in vivo electrophysiological recording system enables examination of behavioral correlates of neural activity at selected epochs of a given cognitive task. We describe protocols for a model system that combines automated visual presentation of information to rodents and intracranial reward with electrophysiological approaches. Our model system offers a sophisticated set of tools as a framework for other cognitive tasks to better isolate and identify specific mechanisms contributing to particular cognitive processes. PMID:24638057

  7. Balancing emotional processing with ongoing cognitive activity: the effects of task modality on intrusions and rumination

    PubMed Central

    Curci, Antonietta; Soleti, Emanuela; Lanciano, Tiziana; Doria, Valentina; Rimé, Bernard

    2015-01-01

    In the present paper we aimed to show that competition for resources between post-emotional processes and the execution of a cognitive task will result in two possible effects: (1) an impairment of the cognitive task in the short run and (2) an elongation of intrusions and rumination in the long run. The outcome of this competition is influenced by the interaction of the modality (verbal vs. visuospatial) of cognitive tasks run in the aftermath of an emotional experience and the nature (verbal vs. visuospatial) of the same experience. Non-clinical participants were given a working memory task (OSPAN vs. an analog Visual task) before and after the presentation of negative vs. neutral material (a novel excerpt in Experiment 1 and a video clip in Experiment 2). Intrusions and rumination were measured after a 24-h delay. Rumination was also assessed immediately after the experimental induction. Results showed that exposure to verbal negative material impaired verbal performance (Experiment 1); by contrast, exposure to visual negative material impaired both verbal and visuospatial performance (Experiment 2). Intrusions were only affected by the emotional valence of the original experience, while performing a visuospatial task resulted in enhanced rumination only after exposure to verbal emotional material. The findings of both experiments suggest that emotional processing spreads over time in balance with ongoing cognitive activities, and, in such a balance, the visuospatial processing mode tends to prevail over verbal engagements. PMID:26379598

  8. Frontal EEG activation asymmetry reflects cognitive biases in anxiety: evidence from an emotional face Stroop task.

    PubMed

    Avram, Julia; Balteş, Felicia Rodica; Miclea, Mircea; Miu, Andrei C

    2010-12-01

    Electroencephalography (EEG) has been extensively used in studies of the frontal asymmetry of emotion and motivation. This study investigated the midfrontal EEG activation, heart rate and skin conductance during an emotional face analog of the Stroop task, in anxious and non-anxious participants. In this task, the participants were asked to identify the expression of calm, fearful and happy faces that had either a congruent or incongruent emotion name written across them. Anxious participants displayed a cognitive bias characterized by facilitated attentional engagement with fearful faces. Fearful face trials induced greater relative right frontal activation, whereas happy face trials induced greater relative left frontal activation. Moreover, anxiety specifically modulated the magnitude of the right frontal activation to fearful faces, which also correlated with the cognitive bias. Therefore, these results show that frontal EEG activation asymmetry reflects the bias toward facilitated processing of fearful faces in anxiety. PMID:20607389

  9. Task-dependent Modulations of Prefrontal and Hippocampal Activity during Intrinsic Word Production

    PubMed Central

    Whitney, Carin; Weis, Susanne; Krings, Timo; Huber, Walter; Grossman, Murray; Kircher, Tilo

    2009-01-01

    Functional imaging studies of single word production have consistently reported activation of the lateral prefrontal and cingulate cortex. Its contribution has been shown to be sensitive to task demands, which can be manipulated by the degree of response specification. Compared with classical verbal fluency, free word association relies less on response restrictions but to a greater extent on associative binding processes, usually subserved by the hippocampus. To elucidate the relevance of the frontal and medial-temporal areas during verbal retrieval tasks, we applied varying degrees of response specification. During fMRI data acquisition, 18 subjects performed a free verbal association (FVA), a semantic verbal fluency (SVF) task, and a phonological verbal fluency (PVF) task. Externally guided word production served as a baseline condition to control for basic articulatory and reading processes. As expected, increased brain activity was observed in the left lateral and bilateral medial frontal cortices for SVF and PVF. The anterior cingulate gyrus was the only structure common to both fluency tasks in direct comparison to the less restricted FVA task. The hippocampus was engaged during associative and semantic retrieval. Interestingly, hippocampal activity was selectively evident during FVA in direct comparison to SVF when it was controlled for stimulus–response relations. The current data confirm the role of the left prefrontal–cingulate network in constrained word production. Hippocampal activity during spontaneous word production is a novel finding and seems to be dependent on the retrieval process (free vs. constrained) rather than the variety of stimulus–response relationships that is involved. PMID:18578599

  10. Trait Anxiety Modulates Brain Activity during Performance of Verbal Fluency Tasks

    PubMed Central

    Gawda, Barbara; Szepietowska, Ewa

    2016-01-01

    Trait anxiety is thought to be associated with pathological anxiety, and a risk factor for psychiatric disorders. The present study examines the brain mechanisms associated with trait anxiety during the performing of verbal fluency tasks. The aim is to show how trait anxiety modulates executive functions as measured by verbal fluency, and to explore the link between verbal fluency and anxiety due to the putative negative biases in high-anxious individuals. Seven tasks of verbal fluency were used: letter “k,” “f,” verbs, “animals,” “vehicles,” “joy,” and “fear.” The results of 35 subjects (whole sample), and 17 subjects (nine men, eight women) selected from the whole sample for the low/high-anxious groups on the basis of Trait Anxiety scores were analyzed. The subjects were healthy, Polish speaking, right-handed and aged from 20 to 35 years old. fMRI (whole-brain analysis with FWE corrections) was used to show the neural signals under active participation in verbal fluency tasks. The results confirm that trait anxiety slightly modulates neural activation during the performance of verbal fluency tasks, especially in the more difficult tasks. Significant differences were found in brain activation during the performance of more complex tasks between individuals with low anxiety and those with high anxiety. Greater activation in the right hemisphere, frontal gyri, and cerebellum was found in people with low anxiety. The results reflect better integration of cognitive and affective capacities in individuals with low anxiety. PMID:26903827

  11. The Relationship between Cortisol Activity during Cognitive Task and Posttraumatic Stress Symptom Clusters

    PubMed Central

    Duan, Hongxia; Wang, Li; Zhang, Liang; Liu, Jing; Zhang, Kan; Wu, Jianhui

    2015-01-01

    Background The latest development in the dimensional structure of posttraumatic stress disorder (PTSD) is a novel 6-factor model, which builds on the newly released DSM-5. One notable gap in the literature is that little is known about how distinct symptom clusters of PTSD are related to hypothalamic–pituitary–adrenal (HPA) axis activity when people perform a relatively less stressful cognitive task. The purpose of this study was to investigate the relationship between cortisol activity when individuals perform cognitive tasks in the laboratory and a contemporary phenotypic model of posttraumatic stress symptomatology in earthquake survivors. Methods Salivary cortisol while performing cognitive tasks was collected and analyzed in 89 adult earthquake survivors. The PTSD Checklist for the DSM-5 (PCL-5) was used to assess the severity of total PTSD as well as six distinct symptom clusters. Regression analyses were conducted to examine the associations between the six distinct PTSD symptom clusters and cortisol profiles. Results The results showed that the score of the negative affect symptom cluster, but not anhedonia or other clusters, was positively associated with cortisol levels before and during the cognitive tasks. Conclusion The results showed that higher cortisol levels before and during cognitive tasks might be specifically linked to a distinct symptom cluster of PTSD—negative affect symptomatology. This suggests that a distinction should be made between negative affect and anhedonia symptom clusters, as the 6-factor model proposed. PMID:26630485

  12. Differences in neural activation as a function of risk-taking task parameters.

    PubMed

    Congdon, Eliza; Bato, Angelica A; Schonberg, Tom; Mumford, Jeanette A; Karlsgodt, Katherine H; Sabb, Fred W; London, Edythe D; Cannon, Tyrone D; Bilder, Robert M; Poldrack, Russell A

    2013-01-01

    Despite evidence supporting a relationship between impulsivity and naturalistic risk-taking, the relationship of impulsivity with laboratory-based measures of risky decision-making remains unclear. One factor contributing to this gap in our understanding is the degree to which different risky decision-making tasks vary in their details. We conducted an fMRI investigation of the Angling Risk Task (ART), which is an improved behavioral measure of risky decision-making. In order to examine whether the observed pattern of neural activation was specific to the ART or generalizable, we also examined correlates of the Balloon Analog Risk Taking (BART) task in the same sample of 23 healthy adults. Exploratory analyses were conducted to examine the relationship between neural activation, performance, impulsivity and self-reported risk-taking. While activation in a valuation network was associated with reward tracking during the ART but not the BART, increased fronto-cingulate activation was seen during risky choice trials in the BART as compared to the ART. Thus, neural activation during risky decision-making trials differed between the two tasks, and this observation was likely driven by differences in task parameters, namely the absence vs. presence of ambiguity and/or stationary vs. increasing probability of loss on the ART and BART, respectively. Exploratory association analyses suggest that sensitivity of neural response to the magnitude of potential reward during the ART was associated with a suboptimal performance strategy, higher scores on a scale of dysfunctional impulsivity (DI) and a greater likelihood of engaging in risky behaviors, while this pattern was not seen for the BART. Our results suggest that the ART is decomposable and associated with distinct patterns of neural activation; this represents a preliminary step toward characterizing a behavioral measure of risky decision-making that may support a better understanding of naturalistic risk-taking.

  13. Report of the NIH Task Force on Research Standards for Chronic Low Back Pain†

    PubMed Central

    Deyo, Richard A.; Dworkin, Samuel F.; Amtmann, Dagmar; Andersson, Gunnar; Borenstein, David; Carragee, Eugene; Carrino, John; Chou, Roger; Cook, Karon; DeLitto, Anthony; Goertz, Christine; Khalsa, Partap; Loeser, John; Mackey, Sean; Panagis, James; Rainville, James; Tosteson, Tor; Turk, Dennis; Von Korff, Michael; Weiner, Debra K.

    2015-01-01

    Despite rapidly increasing intervention, functional disability due to chronic low back pain (cLBP) has increased in recent decades. We often cannot identify mechanisms to explain the major negative impact cLBP has on patients’ lives. Such cLBP is often termed non-specific, and may be due to multiple biologic and behavioral etiologies. Researchers use varied inclusion criteria, definitions, baseline assessments, and outcome measures, which impede comparisons and consensus. The NIH Pain Consortium therefore charged a Research Task Force (RTF) to draft standards for research on cLBP. The resulting multidisciplinary panel recommended using 2 questions to define cLBP; classifying cLBP by its impact (defined by pain intensity, pain interference, and physical function); use of a minimal data set to describe research participants (drawing heavily on the PROMIS methodology); reporting “responder analyses” in addition to mean outcome scores; and suggestions for future research and dissemination. The Pain Consortium has approved the recommendations, which investigators should incorporate into NIH grant proposals. The RTF believes these recommendations will advance the field, help to resolve controversies, and facilitate future research addressing the genomic, neurologic, and other mechanistic substrates of chronic low back pain. We expect the RTF recommendations will become a dynamic document, and undergo continual improvement. Perspective A Task Force was convened by the NIH Pain Consortium, with the goal of developing research standards for chronic low back pain. The results included recommendations for definitions, a minimal dataset, reporting outcomes, and future research. Greater consistency in reporting should facilitate comparisons among studies and the development of phenotypes. PMID:26388962

  14. Left inferior-parietal lobe activity in perspective tasks: identity statements.

    PubMed

    Arora, Aditi; Weiss, Benjamin; Schurz, Matthias; Aichhorn, Markus; Wieshofer, Rebecca C; Perner, Josef

    2015-01-01

    We investigate the theory that the left inferior parietal lobe (IPL) is closely associated with tracking potential differences of perspective. Developmental studies find that perspective tasks are mastered at around 4 years of age. Our first study, meta-analyses of brain imaging studies shows that perspective tasks specifically activate a region in the left IPL and precuneus. These tasks include processing of false belief, visual perspective, and episodic memory. We test the location specificity theory in our second study with an unusual and novel kind of perspective task: identity statements. According to Frege's classical logical analysis, identity statements require appreciation of modes of presentation (perspectives). We show that identity statements, e.g., "the tour guide is also the driver" activate the left IPL in contrast to a control statements, "the tour guide has an apprentice." This activation overlaps with the activations found in the meta-analysis. This finding is confirmed in a third study with different types of statements and different comparisons. All studies support the theory that the left IPL has as one of its overarching functions the tracking of perspective differences. We discuss how this function relates to the bottom-up attention function proposed for the bilateral IPL.

  15. Cognitive Conflict in a Syllable Identification Task Causes Transient Activation of Speech Perception Area

    ERIC Educational Resources Information Center

    Saetrevik, Bjorn; Specht, Karsten

    2012-01-01

    It has previously been shown that task performance and frontal cortical activation increase after cognitive conflict. This has been argued to support a model of attention where the level of conflict automatically adjusts the amount of cognitive control applied. Conceivably, conflict could also modulate lower-level processing pathways, which would…

  16. Beyond Rhyme or Reason: ERPs Reveal Task-Specific Activation of Orthography on Spoken Language

    ERIC Educational Resources Information Center

    Pattamadilok, Chotiga; Perre, Laetitia; Ziegler, Johannes C.

    2011-01-01

    Metaphonological tasks, such as rhyme judgment, have been the primary tool for the investigation of the effects of orthographic knowledge on spoken language. However, it has been recently argued that the orthography effect in rhyme judgment does not reflect the automatic activation of orthographic codes but rather stems from sophisticated response…

  17. Task-Dependent Modulations of Prefrontal and Hippocampal Activity during Intrinsic Word Production

    ERIC Educational Resources Information Center

    Whitney, Carin; Weis, Susanne; Krings, Timo; Huber, Walter; Grossman, Murray; Kircher, Tilo

    2009-01-01

    Functional imaging studies of single word production have consistently reported activation of the lateral prefrontal and cingulate cortex. Its contribution has been shown to be sensitive to task demands, which can be manipulated by the degree of response specification. Compared with classical verbal fluency, free word association relies less on…

  18. Evaluating Integrated Task Based Activities and Computer Assisted Language Learning (CALL)

    ERIC Educational Resources Information Center

    Anwar, Khoirul; Husniah, Rohmy

    2016-01-01

    This study is to evaluate the implementation of Task Activities based on CALL which consist of observing, questioning, exploring, and communicating. The developed materials are nine chapters that had been implemented in two different classes of SMPN 1 Gresik and SMPM 4 Gresik in Indonesia. Of quesionnaires and interviews, the results indicate that…

  19. Left inferior-parietal lobe activity in perspective tasks: identity statements

    PubMed Central

    Arora, Aditi; Weiss, Benjamin; Schurz, Matthias; Aichhorn, Markus; Wieshofer, Rebecca C.; Perner, Josef

    2015-01-01

    We investigate the theory that the left inferior parietal lobe (IPL) is closely associated with tracking potential differences of perspective. Developmental studies find that perspective tasks are mastered at around 4 years of age. Our first study, meta-analyses of brain imaging studies shows that perspective tasks specifically activate a region in the left IPL and precuneus. These tasks include processing of false belief, visual perspective, and episodic memory. We test the location specificity theory in our second study with an unusual and novel kind of perspective task: identity statements. According to Frege's classical logical analysis, identity statements require appreciation of modes of presentation (perspectives). We show that identity statements, e.g., “the tour guide is also the driver” activate the left IPL in contrast to a control statements, “the tour guide has an apprentice.” This activation overlaps with the activations found in the meta-analysis. This finding is confirmed in a third study with different types of statements and different comparisons. All studies support the theory that the left IPL has as one of its overarching functions the tracking of perspective differences. We discuss how this function relates to the bottom-up attention function proposed for the bilateral IPL. PMID:26175677

  20. Individual Differences for Self-Regulating Task-Oriented Reading Activities

    ERIC Educational Resources Information Center

    Vidal-Abarca, Eduardo; Mana, Amelia; Gil, Laura

    2010-01-01

    The goal of this study is to analyze the self-regulation processes present in task-oriented reading activities. In the 1st experiment, we examined the following self-regulation processes in the context of answering questions about an available text: (a) monitoring the comprehension of the question, (b) self-regulating the search process, and (c)…

  1. Task Rotation: Strategies for Differentiating Activities and Assessments by Learning Style. A Strategic Teacher PLC Guide

    ERIC Educational Resources Information Center

    Silver, Harvey; Moirao, Daniel; Jackson, Joyce

    2011-01-01

    One of the hardest jobs in teaching is to differentiate learning activities and assessments to your students' learning styles. But you and your colleagues can learn how to do this together when each of you has this guide to the Task Rotation strategy from our ultimate guide to teaching strategies, "The Strategic Teacher". Use the guide in your…

  2. Atypical activation during the Embedded Figures Task as a functional magnetic resonance imaging endophenotype of autism.

    PubMed

    Spencer, Michael D; Holt, Rosemary J; Chura, Lindsay R; Calder, Andrew J; Suckling, John; Bullmore, Edward T; Baron-Cohen, Simon

    2012-11-01

    Atypical activation during the Embedded Figures Task has been demonstrated in autism, but has not been investigated in siblings or related to measures of clinical severity. We identified atypical activation during the Embedded Figures Task in participants with autism and unaffected siblings compared with control subjects in a number of temporal and frontal brain regions. Autism and sibling groups, however, did not differ in terms of activation during this task. This suggests that the pattern of atypical activation identified may represent a functional endophenotype of autism, related to familial risk for the condition shared between individuals with autism and their siblings. We also found that reduced activation in autism relative to control subjects in regions including associative visual and face processing areas was strongly correlated with the clinical severity of impairments in reciprocal social interaction. Behavioural performance was intact in autism and sibling groups. Results are discussed in terms of atypical information processing styles or of increased activation in temporal and frontal regions in autism and the broader phenotype. By separating the aspects of atypical activation as markers of familial risk for the condition from those that are autism-specific, our findings offer new insight into the factors that might cause the expression of autism in families, affecting some children but not others.

  3. Influence of monkey dorsolateral prefrontal and posterior parietal activity on behavioral choice during attention tasks

    PubMed Central

    Katsuki, Fumi; Saito, Mizuki; Constantinidis, Christos

    2014-01-01

    The dorsolateral prefrontal and the posterior parietal cortex have both been implicated in the guidance of visual attention. Traditionally, posterior parietal cortex has been thought to guide visual bottom-up attention, whereas prefrontal cortex to bias attention through top-down information. More recent studies suggest a parallel time course of activation of the two areas in bottom-up attention tasks, suggesting a common involvement, though these results do not necessarily imply identical roles, either. To address the specific roles of the two areas, we examined the influence of neuronal activity recorded from the prefrontal and parietal cortex of monkeys as they performed attention tasks based on choice probability and correlation between reaction time and neuronal activity. The results revealed that posterior parietal but not dorsolateral prefrontal activity correlated with behavioral choice during the fixation period, prior to the appearance of the stimulus, resembling a bias factor. This preferential influence of posterior parietal activity on behavior was transient, so that dorsolateral prefrontal activity predicted choice after the appearance of the stimulus. Additionally, reaction time was better predicted by posterior parietal activity. These findings confirm an involvement of both dorsolateral prefrontal and posterior parietal cortex in the bottom-up guidance of visual attention but indicate different roles of the two areas in the guidance of attention and a dynamic time course of their effects, influencing behavior at different stages of the task. PMID:24964224

  4. The Technologist Function in Fields Related to Radiology: Tasks in Radiation Therapy and Diagnostic Ultrasound. Research Report No. 9; Relating Technologist Tasks in Diagnostic Radiology, Ultrasound and Radiation Therapy. Research Report No. 10.

    ERIC Educational Resources Information Center

    Gilpatrick, Eleanor

    The two research reports included in this document describe the application of the Health Services Mobility Study (HSMS) task analysis method to two technologist functions and examine the interrelationships of these tasks with those in diagnostic radiology. (The HSMS method includes processes for using the data for designing job ladders, for…

  5. Working together may be better: activation of reward centers during a cooperative maze task.

    PubMed

    Krill, Austen L; Platek, Steven M

    2012-01-01

    Humans use theory of mind when predicting the thoughts and feelings and actions of others. There is accumulating evidence that cooperation with a computerized game correlates with a unique pattern of brain activation. To investigate the neural correlates of cooperation in real-time we conducted an fMRI hyperscanning study. We hypothesized that real-time cooperation to complete a maze task, using a blind-driving paradigm, would activate substrates implicated in theory of mind. We also hypothesized that cooperation would activate neural reward centers more than when participants completed the maze themselves. Of interest and in support of our hypothesis we found left caudate and putamen activation when participants worked together to complete the maze. This suggests that cooperation during task completion is inherently rewarding. This finding represents one of the first discoveries of a proximate neural mechanism for group based interactions in real-time, which indirectly supports the social brain hypothesis.

  6. Flight tests for the assessment of task performance and control activity

    NASA Technical Reports Server (NTRS)

    Pausder, H. J.; Hummes, D.

    1982-01-01

    The tests were performed with the helicopters BO 105 and UH-1D. Closely connected with tactical demands the six test pilots' task was to minimize the time and the altitude over the obstacles. The data reduction yields statistical evaluation parameters describing the control activity of the pilots and the achieved task performance. The results are shown in form of evaluation diagrams. Additionally dolphin tests with varied control strategy were performed to get more insight into the influence of control techniques. From these test results recommendations can be derived to emphasize the direct force control and to reduce the collective to pitch crosscoupling for the dolphin.

  7. Comparison of Lower Extremity Kinematics and Hip Muscle Activation During Rehabilitation Tasks Between Sexes

    PubMed Central

    Dwyer, Maureen K.; Boudreau, Samantha N.; Mattacola, Carl G.; Uhl, Timothy L.; Lattermann, Christian

    2010-01-01

    Abstract Context: Closed kinetic chain exercises are an integral part of rehabilitation programs after lower extremity injury. Sex differences in lower extremity kinematics have been reported during landing and cutting; however, less is known about sex differences in movement patterns and activation of the hip musculature during common lower extremity rehabilitation exercises. Objective: To determine whether lower extremity kinematics and muscle activation levels differ between sexes during closed kinetic chain rehabilitation exercises. Design: Cross-sectional with 1 between-subjects factor (sex) and 1 within-subjects factor (exercise). Setting: Research laboratory. Patients or Other Participants: Participants included 21 women (age  =  23 ± 5.8 years, height  =  167.6 ± 5.1 cm, mass  =  63.7 ± 5.9 kg) and 21 men (age  =  23 ± 4.0 years, height  =  181.4 ± 7.4 cm, mass  =  85.6 ± 16.5 kg). Intervention(s): In 1 testing session, participants performed 3 trials each of single-leg squat, lunge, and step-up-and-over exercises. Main Outcome Measure(s): We recorded the peak joint angles (degrees) of knee flexion and valgus and hip flexion, extension, adduction, and external rotation for each exercise. We also recorded the electromyographic activity of the gluteus maximus, rectus femoris, adductor longus, and bilateral gluteus medius muscles for the concentric and eccentric phases of each exercise. Results: Peak knee flexion angles were smaller and peak hip extension angles were larger for women than for men across all tasks. Peak hip flexion angles during the single-leg squat were smaller for women than for men. Mean root-mean-square amplitudes for the gluteus maximus and rectus femoris muscles in both the concentric and eccentric phases of the 3 exercises were greater for women than for men. Conclusions: Sex differences were observed in sagittal-plane movement patterns during the rehabilitation exercises. Because of the sex differences

  8. Effect of postural angle on back muscle activities in aging female workers performing computer tasks.

    PubMed

    Kamil, Nabilla Sofia Mohd; Dawal, Siti Zawiah Md

    2015-06-01

    [Purpose] This study investigated the effects of postural angle on back muscle activity during a computer task in aging women. [Subjects] Seventeen women ≥50 years old participated. [Methods] The participants were instructed to perform computer-related tasks for 20 minutes on a workstation that simulated typical office working conditions. Back posture was measured from the measured trunk and pelvic angles. Electromyography activities were recorded simultaneously from the cervical erector spinae, longissimus, and multifidus muscles. [Results] The lowest mean percentages of maximum voluntary contraction for the cervical erector spinae and longissimus muscles were obtained when the upper trunk and pelvic angles were between 0° to -5° from the sagittal plane. The back muscle activities increased as the upper trunk and pelvic angles exceeded 0°. Statistical analysis showed significant correlations between upper trunk angle and cervical erector spinae and longissimus muscle activities. Similarly, pelvic angle was significantly correlated with cervical erector spinae and multifidus muscle activities. [Conclusion] A neutral back posture minimizes muscle activities in aging women performing computer tasks.

  9. Brain Activations Related to Saccadic Response Conflict are not Sensitive to Time on Task

    PubMed Central

    Beldzik, Ewa; Domagalik, Aleksandra; Oginska, Halszka; Marek, Tadeusz; Fafrowicz, Magdalena

    2015-01-01

    Establishing a role of the dorsal medial frontal cortex in the performance monitoring and cognitive control has been a challenge to neuroscientists for the past decade. In light of recent findings, the conflict monitoring hypothesis has been elaborated to an action-outcome predictor theory. One of the findings that led to this re-evaluation was the fMRI study in which conflict-related brain activity was investigated in terms of the so-called time on task effect, i.e., a linear increase of the BOLD signal with longer response times. The aim of this study was to investigate brain regions involved in the processing of saccadic response conflict and to account for the time on task effect. A modified spatial cueing task was implemented in the event-related fMRI study with oculomotor responses. The results revealed several brain regions which show higher activity for incongruent trials in comparison to the congruent ones, including pre-supplementary motor area together with the frontal and parietal regions. Further analysis accounting for the effect of response time provided evidence that these brain activations were not sensitive to time on task but reflected purely the congruency effect. PMID:26696871

  10. An 8-Month Randomized Controlled Exercise Trial Alters Brain Activation During Cognitive Tasks in Overweight Children

    PubMed Central

    Krafft, Cynthia E.; Schwarz, Nicolette F.; Chi, Lingxi; Weinberger, Abby L.; Schaeffer, David J.; Pierce, Jordan E.; Rodrigue, Amanda L.; Yanasak, Nathan E.; Miller, Patricia H.; Tomporowski, Phillip D.; Davis, Catherine L.; McDowell, Jennifer E.

    2014-01-01

    Objective Children who are less fit reportedly have lower performance on tests of cognitive control and differences in brain function. This study examined the effect of an exercise intervention on brain function during two cognitive control tasks in overweight children. Design and Methods Participants included 43 unfit, overweight (BMI ≥ 85th percentile) children 8- to 11-years old (91% Black), who were randomly divided into either an aerobic exercise (n = 24) or attention control group (n = 19). Each group was offered a separate instructor-led after-school program every school day for 8 months. Before and after the program, all children performed two cognitive control tasks during functional magnetic resonance imaging (fMRI): antisaccade and flanker. Results Compared to the control group, the exercise group decreased activation in several regions supporting antisaccade performance, including precentral gyrus and posterior parietal cortex, and increased activation in several regions supporting flanker performance, including anterior cingulate and superior frontal gyrus. Conclusions Exercise may differentially impact these two task conditions, or the paradigms in which cognitive control tasks were presented may be sensitive to distinct types of brain activation that show different effects of exercise. In sum, exercise appears to alter efficiency or flexible modulation of neural circuitry supporting cognitive control in overweight children. PMID:23788510

  11. Walking while Performing Working Memory Tasks Changes the Prefrontal Cortex Hemodynamic Activations and Gait Kinematics

    PubMed Central

    Lin, Ming-I B.; Lin, Kuan-Hung

    2016-01-01

    Background: Increasing evidence suggests that walking while performing a concurrent task negatively influences gait performance. However, it remains unclear how higher-level cognitive processes and coordination of limb movements are altered in challenging walking environments. This study investigated the influence of cognitive task complexity and walking road condition on the neutral correlates of executive function and postural control in dual-task walking. Methods: Twenty-four healthy young adults completed a series of overground walks with three walking road conditions (wide, narrow, with obstacles) with and without the concurrent n-back working memory tasks of two complexity levels (1-back and 3-back). Prefrontal brain activation was assessed by functional near-infrared spectroscopy. A three-dimensional motion analysis system was used simultaneously to measure gait performance and lower-extremity kinematics. Repeated measures analysis of variance were performed to examine the differences between the conditions. Results: In comparison with standing still, participants showed lower n-back task accuracy while walking, with the worst performance from the road with obstacles. Spatiotemporal gait parameters, lower-extremity joint movements, and the relative changes in oxygenated hemoglobin (HbO) concentration levels were all significantly different across the task complexity and walking path conditions. While dual-tasking participants were found to flex their hips and knees less, leading to a slower gait speed, longer stride time, shorter step length, and greater gait variability than during normal walking. For narrow-road walking, smaller ankle dorsiflexion and larger hip flexion were observed, along with a reduced gait speed. Obstacle negotiation was mainly characterized by increased gait variability than other conditions. HbO levels appeared to be lower during dual-task walking than normal walking. Compared to wide and obstacle conditions, walking on the narrow

  12. A modelization of the task allocation problem for prescribing activity in an ICU.

    PubMed Central

    Renard, J. M.; Bricon-Souf, N.; Guigue, L.; Beuscart, R.

    2000-01-01

    The improvement of coordination between Health Care Professionals belonging different specialities and who are extremely mobile, is a crucial problem in Medicine. A workflow System is one example of the new informatics tools which facilitate the transfer of information and responsibility between health care providers. Medical informatics systems in particular should be reactive enough to cope with the flexibility of real work situations: in this paper, we present the task allocation problem. We distinguish between the workflow control process and the notifying process, which concerns the sharing out of the tasks between the actors concerned. We focus on the impact of strategies of notification on the progress of coordinated work. We propose a simulator to model and study the different ways of sharing tasks between actors in an Intensive Care Unit's activity of prescription. PMID:11079971

  13. Review of Recent Research Using Constant Time Delay to Teach Chained Tasks to Persons with Developmental Disabilities

    ERIC Educational Resources Information Center

    Dogoe, Maud; Banda, Devender R.

    2009-01-01

    We reviewed twelve studies that used the constant time delay (CTD) procedure to teach chained tasks to individuals with developmental disabilities from years 1996-2006. Variables analyzed include types of tasks that have been taught with the procedure, how effective CTD has been in teaching participants, and whether researchers have investigated…

  14. Urban Consortium Energy Task Force applied research units and projects, 1992 program. Summary and abstracts

    SciTech Connect

    1991-10-01

    This report contains brief descriptions of projects involved in the urban Consortium Energy Task Force (UCETF). The Consortium is a special network which helps to define urban problems, and commercialize technologies which could help solve those problems. Research and Development priorities within the program are transportation, energy, environment, and economic development and energy efficient facilities. The Consortium has established partnerships with US DOE on energy utilities, alternative vehicle fuels, waste management, and electricity management. A technology transfer committee was established to build a marketing program.

  15. Short- and long-term changes in anterior cingulate activation during resolution of task-set competition.

    PubMed

    Woodward, Todd S; Ruff, Christian C; Ngan, Elton T C

    2006-01-12

    Alternating between task sets involves detection that the current task set is unfavorable, initiation of a change in set, and application of the new task set while fine-tuning to optimally adjust to the demands of the environment. Functional magnetic resonance imaging (fMRI) studies of cognitive flexibility consistently report activation of the anterior cingulate cortex and/or adjacent pre-supplementary motor regions (ACC/pre-SMA, medial Brodmann's areas 24/32/6), suggesting that these cortical regions are involved in switching task set. In the current study, our objective was to probe whether ACC/pre-SMA activation would decrease for a number of trials following a switch in task set, implying longer-term involvement in fine-tuning adjustments. By measuring activation when switching between word reading and color naming in response to Stroop stimuli, ACC/pre-SMA activation was observed when actively countering the influence of the irrelevant task set, and this activation decreased as a function of the number of trials since a task switch. Basal ganglia and thalamic regions also displayed a decreased response over successive trials after task switches. These findings suggest that the ACC/pre-SMA are not only involved in generating a new course of action, but are also involved (along with subcortical regions) in fine-tuning operations that resolve competition between task sets over subsequent repetitions of the same task. PMID:16376861

  16. National facilities study. Volume 5: Space research and development facilities task group

    NASA Technical Reports Server (NTRS)

    1994-01-01

    With the beginnings of the U.S. space program, there was a pressing need to develop facilities that could support the technology research and development, testing, and operations of evolving space systems. Redundancy in facilities that was once and advantage in providing flexibility and schedule accommodation is instead fast becoming a burden on scarce resources. As a result, there is a clear perception in many sectors that the U.S. has many space R&D facilities that are under-utilized and which are no longer cost-effective to maintain. At the same time, it is clear that the U.S. continues to possess many space R&D facilities which are the best -- or among the best -- in the world. In order to remain world class in key areas, careful assessment of current capabilities and planning for new facilities is needed. The National Facility Study (NFS) was initiated in 1992 to develop a comprehensive and integrated long-term plan for future aerospace facilities that meets current and projected government and commercial needs. In order to assess the nation's capability to support space research and development (R&D), a Space R&D Task Group was formed. The Task Group was co-chaired by NASA and DOD. The Task Group formed four major, technologically- and functionally- oriented working groups: Human and Machine Operations; Information and Communications; Propulsion and Power; and Materials, Structures, and Flight Dynamics. In addition to these groups, three supporting working groups were formed: Systems Engineering and Requirements; Strategy and Policy; and Costing Analysis. The Space R&D Task Group examined several hundred facilities against the template of a baseline mission and requirements model (developed in common with the Space Operations Task Group) and a set of excursions from the baseline. The model and excursions are described in Volume 3 of the NFS final report. In addition, as a part of the effort, the group examined key strategic issues associated with space R

  17. Predicting hand orientation in reach-to-grasp tasks using neural activities from primary motor cortex.

    PubMed

    Zhang, Peng; Ma, Xuan; Huang, Hailong; He, Jiping

    2014-01-01

    Hand orientation is an important control parameter during reach-to-grasp task. In this paper, we presented a study for predicting hand orientation of non-human primate by decoding neural activities from primary motor cortex (M1). A non-human primate subject was guided to do reaching and grasping tasks meanwhile neural activities were acquired by chronically implanted microelectrode arrays. A Support Vector Machines (SVMs) classifier has been trained for predicting three different hand orientations using these M1 neural activities. Different number of neurons were selected and analyzed; the classifying accuracy was 94.1% with 2 neurons and was 100% with 8 neurons. Data from highly event related neuron units contribute a lot to the accuracy of hand orientation prediction. These results indicate that three different hand orientations can be predicted accurately and effectively before the actual movements occurring with a small number of related neurons in M1.

  18. Rhesus leg muscle EMG activity during a foot pedal pressing task on Bion 11

    NASA Technical Reports Server (NTRS)

    Hodgson, J. A.; Riazansky, S. N.; Goulet, C.; Badakva, A. M.; Kozlovskaya, I. B.; Recktenwald, M. R.; McCall, G.; Roy, R. R.; Fanton, J. W.; Edgerton, V. R.

    2000-01-01

    Rhesus monkeys (Macaca mulatta) were trained to perform a foot lever pressing task for a food reward. EMG activity was recorded from selected lower limb muscles of 2 animals before, during, and after a 14-day spaceflight and from 3 animals during a ground-based simulation of the flight. Integrated EMG activity was calculated for each muscle during the 20-min test. Comparisons were made between data recorded before any experimental manipulations and during flight or flight simulation. Spaceflight reduced soleus (Sol) activity to 25% of preflight levels, whereas it was reduced to 50% of control in the flight simulation. During flight, medial gastrocnemius (MG) activity was reduced to 25% of preflight activity, whereas the simulation group showed normal activity levels throughout all tests. The change in MG activity was apparent in the first inflight recording, suggesting that some effect of microgravity on MG activity was immediate.

  19. Task Performance and Meta-Cognitive Outcomes When Using Activity Workstations and Traditional Desks

    PubMed Central

    Pilcher, June J.; Baker, Victoria C.

    2016-01-01

    The purpose of the current study is to compare the effects of light physical activity to sedentary behavior on cognitive task performance and meta-cognitive responses. Thirty-eight undergraduate students participated in the study. The participants used a stationary bicycle with a desk top and a traditional desk while completing two complex cognitive tasks and measures of affect, motivation, morale, and engagement. The participants pedaled the stationary bicycle at a slow pace (similar in exertion to a normal walking pace) while working. The results indicated that cognitive task performance did not change between the two workstations. However, positive affect, motivation, and morale improved when using the stationary bicycle. These results suggest that activity workstations could be implemented in the work place and in educational settings to help decrease sedentary behavior without negatively affecting performance. Furthermore, individuals could experience a positive emotional response when working on activity workstations which in turn could help encourage individuals to choose to be more physical active during daily activities. PMID:27445921

  20. Muscle activation during the Pack Hike test and a critical wildfire fighting task.

    PubMed

    Netto, Kevin; Lord, Cara; Petersen, Aaron; Janssen, James; Nichols, David; Aisbett, Brad

    2013-03-01

    The aim of this study was to examine the muscle activation of six global muscles during the successful completion of the Pack Hike test (PHT) and compare this to muscle activations during a critical wildfire fighting task. In-field surface electromyography was recorded from eight male wildfire fighters during the PHT and the rakehoe task - a critical wildfire suppression activity. All participants successfully completed the PHT within the 45-min time limit. No significant changes in peak muscle activation levels as well as no significant shifts in median frequency in the six muscle analysed were recorded during the 4.83-km hike. Significantly different peak muscle activation levels were recorded in four of the six muscles tested when the PHT was compared to the rakehoe task. These results suggest the PHT should not be administered in isolation and other tests that specifically challenge upper body muscle endurance should be incorporated into a battery that accurately assesses the job-specific fitness of wildfire fighters.

  1. Muscle activation during the Pack Hike test and a critical wildfire fighting task.

    PubMed

    Netto, Kevin; Lord, Cara; Petersen, Aaron; Janssen, James; Nichols, David; Aisbett, Brad

    2013-03-01

    The aim of this study was to examine the muscle activation of six global muscles during the successful completion of the Pack Hike test (PHT) and compare this to muscle activations during a critical wildfire fighting task. In-field surface electromyography was recorded from eight male wildfire fighters during the PHT and the rakehoe task - a critical wildfire suppression activity. All participants successfully completed the PHT within the 45-min time limit. No significant changes in peak muscle activation levels as well as no significant shifts in median frequency in the six muscle analysed were recorded during the 4.83-km hike. Significantly different peak muscle activation levels were recorded in four of the six muscles tested when the PHT was compared to the rakehoe task. These results suggest the PHT should not be administered in isolation and other tests that specifically challenge upper body muscle endurance should be incorporated into a battery that accurately assesses the job-specific fitness of wildfire fighters. PMID:22981470

  2. Motivation alters response bias and neural activation patterns in a perceptual decision-making task.

    PubMed

    Reckless, G E; Bolstad, I; Nakstad, P H; Andreassen, O A; Jensen, J

    2013-05-15

    Motivation has been demonstrated to affect individuals' response strategies in economic decision-making, however, little is known about how motivation influences perceptual decision-making behavior or its related neural activity. Given the important role motivation plays in shaping our behavior, a better understanding of this relationship is needed. A block-design, continuous performance, perceptual decision-making task where participants were asked to detect a picture of an animal among distractors was used during functional magnetic resonance imaging (fMRI). The effect of positive and negative motivation on sustained activity within regions of the brain thought to underlie decision-making was examined by altering the monetary contingency associated with the task. In addition, signal detection theory was used to investigate the effect of motivation on detection sensitivity, response bias and response time. While both positive and negative motivation resulted in increased sustained activation in the ventral striatum, fusiform gyrus, left dorsolateral prefrontal cortex (DLPFC) and ventromedial prefrontal cortex, only negative motivation resulted in the adoption of a more liberal, closer to optimal response bias. This shift toward a liberal response bias correlated with increased activation in the left DLPFC, but did not result in improved task performance. The present findings suggest that motivation alters aspects of the way perceptual decisions are made. Further, this altered response behavior is reflected in a change in left DLPFC activation, a region involved in the computation of perceptual decisions.

  3. Task Performance and Meta-Cognitive Outcomes When Using Activity Workstations and Traditional Desks.

    PubMed

    Pilcher, June J; Baker, Victoria C

    2016-01-01

    The purpose of the current study is to compare the effects of light physical activity to sedentary behavior on cognitive task performance and meta-cognitive responses. Thirty-eight undergraduate students participated in the study. The participants used a stationary bicycle with a desk top and a traditional desk while completing two complex cognitive tasks and measures of affect, motivation, morale, and engagement. The participants pedaled the stationary bicycle at a slow pace (similar in exertion to a normal walking pace) while working. The results indicated that cognitive task performance did not change between the two workstations. However, positive affect, motivation, and morale improved when using the stationary bicycle. These results suggest that activity workstations could be implemented in the work place and in educational settings to help decrease sedentary behavior without negatively affecting performance. Furthermore, individuals could experience a positive emotional response when working on activity workstations which in turn could help encourage individuals to choose to be more physical active during daily activities. PMID:27445921

  4. Correlations in background activity control persistent state stability and allow execution of working memory tasks

    PubMed Central

    Dipoppa, Mario; Gutkin, Boris S.

    2013-01-01

    Working memory (WM) requires selective information gating, active information maintenance, and rapid active updating. Hence performing a WM task needs rapid and controlled transitions between neural persistent activity and the resting state. We propose that changes in correlations in neural activity provides a mechanism for the required WM operations. As a proof of principle, we implement sustained activity and WM in recurrently coupled spiking networks with neurons receiving excitatory random background activity where background correlations are induced by a common noise source. We first characterize how the level of background correlations controls the stability of the persistent state. With sufficiently high correlations, the sustained state becomes practically unstable, so it cannot be initiated by a transient stimulus. We exploit this in WM models implementing the delay match to sample task by modulating flexibly in time the correlation level at different phases of the task. The modulation sets the network in different working regimes: more prompt to gate in a signal or clear the memory. We examine how the correlations affect the ability of the network to perform the task when distractors are present. We show that in a winner-take-all version of the model, where two populations cross-inhibit, correlations make the distractor blocking robust. In a version of the mode where no cross inhibition is present, we show that appropriate modulation of correlation levels is sufficient to also block the distractor access while leaving the relevant memory trace in tact. The findings presented in this manuscript can form the basis for a new paradigm about how correlations are flexibly controlled by the cortical circuits to execute WM operations. PMID:24155714

  5. When the brain simulates stopping: Neural activity recorded during real and imagined stop-signal tasks.

    PubMed

    González-Villar, Alberto J; Bonilla, F Mauricio; Carrillo-de-la-Peña, María T

    2016-10-01

    It has been suggested that mental rehearsal activates brain areas similar to those activated by real performance. Although inhibition is a key function of human behavior, there are no previous reports of brain activity during imagined response cancellation. We analyzed event-related potentials (ERPs) and time-frequency data associated with motor execution and inhibition during real and imagined performance of a stop-signal task. The ERPs characteristic of stop trials-that is, the stop-N2 and stop-P3-were also observed during covert performance of the task. Imagined stop (IS) trials yielded smaller stop-N2 amplitudes than did successful stop (SS) and unsuccessful stop (US) trials, but midfrontal theta power similar to that in SS trials. The stop-P3 amplitude for IS was intermediate between those observed for SS and US. The results may be explained by the absence of error-processing and correction processes during imagined performance. For go trials, real execution was associated with higher mu and beta desynchronization over motor areas, which confirms previous reports of lower motor activation during imagined execution and also with larger P3b amplitudes, probably indicating increased top-down attention to the real task. The similar patterns of activity observed for imagined and real performance suggest that imagination tasks may be useful for training inhibitory processes. Nevertheless, brain activation was generally weaker during mental rehearsal, probably as a result of the reduced engagement of top-down mechanisms and limited error processing. PMID:27160368

  6. Evaluating Signal-Correlated Noise as a Control Task with Language-Related Gamma Activity on Electrocorticography

    PubMed Central

    Brown, Erik C.; Muzik, Otto; Rothermel, Robert; Juhász, Csaba; Shah, Aashit K.; Fuerst, Darren; Mittal, Sandeep; Sood, Sandeep; Asano, Eishi

    2014-01-01

    Objective Our recent electrocorticography (ECoG) study suggested reverse speech, a widely used control task, to be a poor control for non-language-related auditory activity. We hypothesized that this may be due to retained perception as a human voice. We report a follow-up ECoG study in which we contrast forward and reverse speech with a signal-correlated noise (SCN) control task that cannot be perceived as a human voice. Methods Ten patients were presented 90 audible stimuli, including 30 each of corresponding forward speech, reverse speech, and SCN trials, during ECoG recording with evaluation of gamma activity between 50–150 Hz. Results Sites of the lateral temporal gyri activated throughout speech stimuli were generally less activated by SCN, while some temporal sites seemed to process both human and non-human sounds. Reverse speech trials were associated with activities across the temporal lobe similar to those associated with forward speech. Conclusions Findings herein externally validate functional neuroimaging studies utilizing SCN as a control for non-language-specific auditory function. Our findings are consistent with the notion that stimuli perceived as originating from a human voice are poor controls for non-language auditory function. Significance Our findings have implications in functional neuroimaging research as well as improved clinical mapping of auditory functions. PMID:24412331

  7. Hormonal contraceptives masculinize brain activation patterns in the absence of behavioral changes in two numerical tasks.

    PubMed

    Pletzer, Belinda; Kronbichler, Martin; Nuerk, Hans-Christoph; Kerschbaum, Hubert

    2014-01-16

    The aim of the present study was to identify, whether and how oral hormonal contraceptives (OCs) alter women's number processing. Behavioral performance and brain activation patterns (BOLD-response) of 14 OC-users were evaluated during two distinct numerical tasks (number comparison, number bisection) and compared to 16 men (high testosterone), and 16 naturally cycling women, once during their follicular (low hormone levels) and once during their luteal cycle phase (high progesterone). For both tasks, reliable sex differences and menstrual cycle dependent modulation have previously been described. If progestogenic effects of the synthetic progestins contained in OC play a predominant role, OC-users should be comparable to luteal women. If androgenic effects of the synthetic steroids exert the progestogenic actions, OC-users should be comparable to men. Likewise, if neither of the above are the case, the reduction of endogenous steroids by OCs should make OC-users comparable to follicular women. Our findings suggest that OC-users resemble follicular women in their behavioral performance, but show male-like brain activation patterns during both tasks. Analysis of brain-behavior relationships suggests that OC-users differ from naturally cycling women in the way they recruit their neural resources to deal with challenges of the tasks. We conclude that OCs, which are used by 100 million women worldwide, may have profound effects on cognition that have not been recognized so far. PMID:24231554

  8. Dynamic trajectory of multiple single-unit activity during working memory task in rats

    PubMed Central

    Zhang, Xiaofan; Yi, Hu; Bai, Wenwen; Tian, Xin

    2015-01-01

    Working memory plays an important role in complex cognitive tasks. A popular theoretical view is that transient properties of neuronal dynamics underlie cognitive processing. The question raised here as to how the transient dynamics evolve in working memory. To address this issue, we investigated the multiple single-unit activity dynamics in rat medial prefrontal cortex (mPFC) during a Y-maze working memory task. The approach worked by reconstructing state space from delays of the original single-unit firing rate variables, which were further analyzed using kernel principal component analysis (KPCA). Then the neural trajectories were obtained to visualize the multiple single-unit activity. Furthermore, the maximal Lyapunov exponent (MLE) was calculated to quantitatively evaluate the neural trajectories during the working memory task. The results showed that the neuronal activity produced stable and reproducible neural trajectories in the correct trials while showed irregular trajectories in the incorrect trials, which may establish a link between the neurocognitive process and behavioral performance in working memory. The MLEs significantly increased during working memory in the correctly performed trials, indicating an increased divergence of the neural trajectories. In the incorrect trials, the MLEs were nearly zero and remained unchanged during the task. Taken together, the trial-specific neural trajectory provides an effective way to track the instantaneous state of the neuronal population during the working memory task and offers valuable insights into working memory function. The MLE describes the changes of neural dynamics in working memory and may reflect different neuronal population states in working memory. PMID:26441626

  9. Comparison of continuously acquired resting state and extracted analogues from active tasks

    PubMed Central

    Ganger, Sebastian; Hahn, Andreas; Küblböck, Martin; Kranz, Georg S.; Spies, Marie; Vanicek, Thomas; Seiger, René; Sladky, Ronald; Windischberger, Christian; Kasper, Siegfried

    2015-01-01

    Abstract Functional connectivity analysis of brain networks has become an important tool for investigation of human brain function. Although functional connectivity computations are usually based on resting‐state data, the application to task‐specific fMRI has received growing attention. Three major methods for extraction of resting‐state data from task‐related signal have been proposed (1) usage of unmanipulated task data for functional connectivity; (2) regression against task effects, subsequently using the residuals; and (3) concatenation of baseline blocks located in‐between task blocks. Despite widespread application in current research, consensus on which method best resembles resting‐state seems to be missing. We, therefore, evaluated these techniques in a sample of 26 healthy controls measured at 7 Tesla. In addition to continuous resting‐state, two different task paradigms were assessed (emotion discrimination and right finger‐tapping) and five well‐described networks were analyzed (default mode, thalamus, cuneus, sensorimotor, and auditory). Investigating the similarity to continuous resting‐state (Dice, Intraclass correlation coefficient (ICC), R 2) showed that regression against task effects yields functional connectivity networks most alike to resting‐state. However, all methods exhibited significant differences when compared to continuous resting‐state and similarity metrics were lower than test‐retest of two resting‐state scans. Omitting global signal regression did not change these findings. Visually, the networks are highly similar, but through further investigation marked differences can be found. Therefore, our data does not support referring to resting‐state when extracting signals from task designs, although functional connectivity computed from task‐specific data may indeed yield interesting information. Hum Brain Mapp 36:4053–4063, 2015. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals

  10. Clean Coal Program Research Activities

    SciTech Connect

    Larry Baxter; Eric Eddings; Thomas Fletcher; Kerry Kelly; JoAnn Lighty; Ronald Pugmire; Adel Sarofim; Geoffrey Silcox; Phillip Smith; Jeremy Thornock; Jost Wendt; Kevin Whitty

    2009-03-31

    Although remarkable progress has been made in developing technologies for the clean and efficient utilization of coal, the biggest challenge in the utilization of coal is still the protection of the environment. Specifically, electric utilities face increasingly stringent restriction on the emissions of NO{sub x} and SO{sub x}, new mercury emission standards, and mounting pressure for the mitigation of CO{sub 2} emissions, an environmental challenge that is greater than any they have previously faced. The Utah Clean Coal Program addressed issues related to innovations for existing power plants including retrofit technologies for carbon capture and sequestration (CCS) or green field plants with CCS. The Program focused on the following areas: simulation, mercury control, oxycoal combustion, gasification, sequestration, chemical looping combustion, materials investigations and student research experiences. The goal of this program was to begin to integrate the experimental and simulation activities and to partner with NETL researchers to integrate the Program's results with those at NETL, using simulation as the vehicle for integration and innovation. The investigators also committed to training students in coal utilization technology tuned to the environmental constraints that we face in the future; to this end the Program supported approximately 12 graduate students toward the completion of their graduate degree in addition to numerous undergraduate students. With the increased importance of coal for energy independence, training of graduate and undergraduate students in the development of new technologies is critical.

  11. Global oral health inequalities: dental caries task group--research agenda.

    PubMed

    Pitts, N; Amaechi, B; Niederman, R; Acevedo, A-M; Vianna, R; Ganss, C; Ismail, A; Honkala, E

    2011-05-01

    The IADR Global Oral Health Inequalities Task Group on Dental Caries has synthesized current evidence and opinion to identify a five-year implementation and research agenda which should lead to improvements in global oral health, with particular reference to the implementation of current best evidence as well as integrated action to reduce caries and health inequalities between and within countries. The Group determined that research should: integrate health and oral health wherever possible, using common risk factors; be able to respond to and influence international developments in health, healthcare, and health payment systems as well as dental prevention and materials; and exploit the potential for novel funding partnerships with industry and foundations. More effective communication between and among the basic science, clinical science, and health promotion/public health research communities is needed. Translation of research into policy and practice should be a priority for all. Both community and individual interventions need tailoring to achieve a more equal and person-centered preventive focus and reduce any social gradient in health. Recommendations are made for both clinical and public health implementation of existing research and for caries-related research agendas in clinical science, health promotion/public health, and basic science.

  12. Payload crew activity planning integration. Task 2: Inflight operations and training for payloads

    NASA Technical Reports Server (NTRS)

    Hitz, F. R.

    1976-01-01

    The primary objectives of the Payload Crew Activity Planning Integration task were to: (1) Determine feasible, cost-effective payload crew activity planning integration methods. (2) Develop an implementation plan and guidelines for payload crew activity plan (CAP) integration between the JSC Orbiter planners and the Payload Centers. Subtask objectives and study activities were defined as: (1) Determine Crew Activity Planning Interfaces. (2) Determine Crew Activity Plan Type and Content. (3) Evaluate Automated Scheduling Tools. (4) Develop a draft Implementation Plan for Crew Activity Planning Integration. The basic guidelines were to develop a plan applicable to the Shuttle operations timeframe, utilize existing center resources and expertise as much as possible, and minimize unnecessary data exchange not directly productive in the development of the end-product timelines.

  13. The Indirect Effect of Age Group on Switch Costs via Gray Matter Volume and Task-Related Brain Activity.

    PubMed

    Steffener, Jason; Gazes, Yunglin; Habeck, Christian; Stern, Yaakov

    2016-01-01

    Healthy aging simultaneously affects brain structure, brain function, and cognition. These effects are often investigated in isolation ignoring any relationships between them. It is plausible that age related declines in cognitive performance are the result of age-related structural and functional changes. This straightforward idea is tested in within a conceptual research model of cognitive aging. The current study tested whether age-related declines in task-performance were explained by age-related differences in brain structure and brain function using a task-switching paradigm in 175 participants. Sixty-three young and 112 old participants underwent MRI scanning of brain structure and brain activation. The experimental task was an executive context dual task with switch costs in response time as the behavioral measure. A serial mediation model was applied voxel-wise throughout the brain testing all pathways between age group, gray matter volume, brain activation and increased switch costs, worsening performance. There were widespread age group differences in gray matter volume and brain activation. Switch costs also significantly differed by age group. There were brain regions demonstrating significant indirect effects of age group on switch costs via the pathway through gray matter volume and brain activation. These were in the bilateral precuneus, bilateral parietal cortex, the left precentral gyrus, cerebellum, fusiform, and occipital cortices. There were also significant indirect effects via the brain activation pathway after controlling for gray matter volume. These effects were in the cerebellum, occipital cortex, left precentral gyrus, bilateral supramarginal, bilateral parietal, precuneus, middle cingulate extending to medial superior frontal gyri and the left middle frontal gyri. There were no significant effects through the gray matter volume alone pathway. These results demonstrate that a large proportion of the age group effect on switch costs can

  14. The Indirect Effect of Age Group on Switch Costs via Gray Matter Volume and Task-Related Brain Activity

    PubMed Central

    Steffener, Jason; Gazes, Yunglin; Habeck, Christian; Stern, Yaakov

    2016-01-01

    Healthy aging simultaneously affects brain structure, brain function, and cognition. These effects are often investigated in isolation ignoring any relationships between them. It is plausible that age related declines in cognitive performance are the result of age-related structural and functional changes. This straightforward idea is tested in within a conceptual research model of cognitive aging. The current study tested whether age-related declines in task-performance were explained by age-related differences in brain structure and brain function using a task-switching paradigm in 175 participants. Sixty-three young and 112 old participants underwent MRI scanning of brain structure and brain activation. The experimental task was an executive context dual task with switch costs in response time as the behavioral measure. A serial mediation model was applied voxel-wise throughout the brain testing all pathways between age group, gray matter volume, brain activation and increased switch costs, worsening performance. There were widespread age group differences in gray matter volume and brain activation. Switch costs also significantly differed by age group. There were brain regions demonstrating significant indirect effects of age group on switch costs via the pathway through gray matter volume and brain activation. These were in the bilateral precuneus, bilateral parietal cortex, the left precentral gyrus, cerebellum, fusiform, and occipital cortices. There were also significant indirect effects via the brain activation pathway after controlling for gray matter volume. These effects were in the cerebellum, occipital cortex, left precentral gyrus, bilateral supramarginal, bilateral parietal, precuneus, middle cingulate extending to medial superior frontal gyri and the left middle frontal gyri. There were no significant effects through the gray matter volume alone pathway. These results demonstrate that a large proportion of the age group effect on switch costs can

  15. Working memory training is associated with lower prefrontal cortex activation in a divergent thinking task.

    PubMed

    Vartanian, O; Jobidon, M-E; Bouak, F; Nakashima, A; Smith, I; Lam, Q; Cheung, B

    2013-04-16

    Working memory (WM) training has been shown to lead to improvements in WM capacity and fluid intelligence. Given that divergent thinking loads on WM and fluid intelligence, we tested the hypothesis that WM training would improve performance and moderate neural function in the Alternate Uses Task (AUT)-a classic test of divergent thinking. We tested this hypothesis by administering the AUT in the functional magnetic resonance imaging scanner following a short regimen of WM training (experimental condition), or engagement in a choice reaction time task not expected to engage WM (active control condition). Participants in the experimental group exhibited significant improvement in performance in the WM task as a function of training, as well as a significant gain in fluid intelligence. Although the two groups did not differ in their performance on the AUT, activation was significantly lower in the experimental group in ventrolateral prefrontal and dorsolateral prefrontal cortices-two brain regions known to play dissociable and critical roles in divergent thinking. Furthermore, gain in fluid intelligence mediated the effect of training on brain activation in ventrolateral prefrontal cortex. These results indicate that a short regimen of WM training is associated with lower prefrontal activation-a marker of neural efficiency-in divergent thinking.

  16. Matching software practitioner needs to researcher activities

    NASA Technical Reports Server (NTRS)

    Feather, M. S.; Menzies, T.; Connelly, J. R.

    2003-01-01

    We present an approach to matching software practitioners' needs to software researchers' activities. It uses an accepted taxonomical software classfication scheme as intermediary, in terms of which practitioners express needs, and researchers express activities.

  17. Age-Related Differences in Cortical Activity during a Visuo-Spatial Working Memory Task with Facial Stimuli

    PubMed Central

    Belham, Flávia Schechtman; Satler, Corina; Garcia, Ana; Tomaz, Carlos; Gasbarri, Antonella; Rego, Artur; Tavares, Maria Clotilde H.

    2013-01-01

    Emotion, importantly displayed by facial expressions, is one of the most significant memory modulators. The interaction between memory and the different emotional valences change across lifespan, while young adults (YA) are expected to better recall negative events (Negativity Bias Hypothesis), older adults (OA) tend to focus on positive stimuli (Positivity Effect Hypothesis). This research work aims at verifying whether cortical electrical activity of these two age groups would also be differently influenced by emotional valences in a visuo-spatial working memory task. 27 YA (13 males) and 25 OA (14 males), all healthy volunteers, underwent electroencephalographic recordings (21 scalp electrodes montage), while performing the Spatial Delayed Recognition Span Task using a touch screen with different stimuli categories: neutral, positive and negative faces and geometric pictures. YA obtained higher scores than OA, and showed higher activation of theta and alpha bands in the frontal and midline regions, besides a more evident right-hemispheric asymmetry on alpha band when compared to OA. For both age groups, performance in the task was worse for positive faces than to negative and to neutral faces. Facial stimuli induced a better performance and higher alpha activation on the pre-frontal region for YA, and on the midline, occipital and left temporal regions for OA when compared to geometric figures. The superior performance of YA was expected due to the natural cognitive deficits connected to ageing, as was a better performance with facial stimuli due to the evolutionary importance of faces. These results were related to cortical activity on areas of importance for action-planning, decision making and sustained attention. Taken together, they are in accordance with the Negativity Bias but do not support the Positivity Effect. The methodology used was able to identify age-related differences in cortical activity during emotional mnemonic processing and may be

  18. Maintaining Gait Performance by Cortical Activation during Dual-Task Interference: A Functional Near-Infrared Spectroscopy Study.

    PubMed

    Lu, Chia-Feng; Liu, Yan-Ci; Yang, Yea-Ru; Wu, Yu-Te; Wang, Ray-Yau

    2015-01-01

    In daily life, mobility requires walking while performing a cognitive or upper-extremity motor task. Although previous studies have evaluated the effects of dual tasks on gait performance, few studies have evaluated cortical activation and its association with gait disturbance during dual tasks. In this study, we simultaneously assessed gait performance and cerebral oxygenation in the bilateral prefrontal cortices (PFC), premotor cortices (PMC), and supplemental motor areas (SMA), using functional near-infrared spectroscopy, in 17 young adults performing dual tasks. Each participant was evaluated while performing normal-pace walking (NW), walking while performing a cognitive task (WCT), and walking while performing a motor task (WMT). Our results indicated that the left PFC exhibited the strongest and most sustained activation during WCT, and that NW and WMT were associated with minor increases in oxygenation levels during their initial phases. We observed increased activation in channels in the SMA and PMC during WCT and WMT. Gait data indicated that WCT and WMT both caused reductions in walking speed, but these reductions resulted from differing alterations in gait properties. WCT was associated with significant changes in cadence, stride time, and stride length, whereas WMT was associated with reductions in stride length only. During dual-task activities, increased activation of the PMC and SMA correlated with declines in gait performance, indicating a control mechanism for maintaining gait performance during dual tasks. Thus, the regulatory effects of cortical activation on gait behavior enable a second task to be performed while walking.

  19. Maintaining Gait Performance by Cortical Activation during Dual-Task Interference: A Functional Near-Infrared Spectroscopy Study

    PubMed Central

    Yang, Yea-Ru; Wu, Yu-Te; Wang, Ray-Yau

    2015-01-01

    In daily life, mobility requires walking while performing a cognitive or upper-extremity motor task. Although previous studies have evaluated the effects of dual tasks on gait performance, few studies have evaluated cortical activation and its association with gait disturbance during dual tasks. In this study, we simultaneously assessed gait performance and cerebral oxygenation in the bilateral prefrontal cortices (PFC), premotor cortices (PMC), and supplemental motor areas (SMA), using functional near-infrared spectroscopy, in 17 young adults performing dual tasks. Each participant was evaluated while performing normal-pace walking (NW), walking while performing a cognitive task (WCT), and walking while performing a motor task (WMT). Our results indicated that the left PFC exhibited the strongest and most sustained activation during WCT, and that NW and WMT were associated with minor increases in oxygenation levels during their initial phases. We observed increased activation in channels in the SMA and PMC during WCT and WMT. Gait data indicated that WCT and WMT both caused reductions in walking speed, but these reductions resulted from differing alterations in gait properties. WCT was associated with significant changes in cadence, stride time, and stride length, whereas WMT was associated with reductions in stride length only. During dual-task activities, increased activation of the PMC and SMA correlated with declines in gait performance, indicating a control mechanism for maintaining gait performance during dual tasks. Thus, the regulatory effects of cortical activation on gait behavior enable a second task to be performed while walking. PMID:26079605

  20. Advanced ASON prototyping research activities in China

    NASA Astrophysics Data System (ADS)

    Hu, WeiSheng; Jin, Yaohui; Guo, Wei; Su, Yikai; He, Hao; Sun, Weiqiang

    2005-02-01

    This paper provides an overview of prototyping research activities of automatically switched optical networks and transport networks (ASONs/ASTNs) in China. In recent years, China has recognized the importance and benefits of the emerging ASON/ASTN techniques. During the period of 2001 and 2002, the national 863 Program of China started the preliminary ASON research projects with the main objectives to build preliminary ASON testbeds, develop control plane protocols and test their performance in the testbeds. During the period of 2003 and 2004, the 863 program started ASTN prototyping equipment projects for more practical applications. Totally 12 ASTN equipments are being developed by three groups led by Chinese venders: ZTE with Beijing University of Posts and Telecommunications (BUPT), Wuhan Research Institute of Posts and Telecommunication (WRI) with Shanghai Jiao Tong University (SJTU), and Huawei Inc. Meanwhile, as the ASTN is maturing, some of the China"s carries are participating in the OIF"s World Interoperability Demonstration, carrying out ASTN test, or deploying ASTN backbone networks. Finally, several ASTN backbone networks being tested or deployed now will be operated by the carries in 2005. The 863 Program will carry out an ASTN field trail in Yangtse River Delta, and finally deploy the 3TNET. 3TNET stands for Tbps transmission, Tbps switching, and Tbps routing, as well as a network integrating the above techniques. A task force under the "863" program is responsible for ASTN equipment specifications and interoperation agreements, technical coordination among all the participants, schedule of the whole project during the project undergoing, and organization of internetworking of all the equipments in the laboratories and field trials.

  1. Sleep is associated with task-negative brain activity in fibromyalgia participants with comorbid chronic insomnia.

    PubMed

    Vatthauer, Karlyn E; Craggs, Jason G; Robinson, Michael E; Staud, Roland; Berry, Richard B; Perlstein, William M; McCrae, Christina S

    2015-01-01

    Patients with chronic pain exhibit altered default mode network (DMN) activity. This preliminary project questioned whether comorbid disease states are associated with further brain alterations. Thirteen women with fibromyalgia (FM) only and 26 women with fibromyalgia with comorbid chronic insomnia (FMI) underwent a single night of ambulatory polysomnography and completed a sleep diary each morning for 14 days prior to performing a neuroimaging protocol. Novel imaging analyses were utilized to identify regions associated with significantly disordered sleep that were more active in task-negative periods than task-oriented periods in participants with FMI, when compared to participants with FM. It was hypothesized that core DMN areas (ie, cingulate cortex, inferior parietal lobule, medial prefrontal cortex, medial temporal cortex, precuneus) would exhibit increased activity during task-negative periods. Analyses revealed that significantly disordered sleep significantly contributed to group differences in the right cingulate gyrus, left lentiform nucleus, left anterior cingulate, left superior gyrus, medial frontal gyrus, right caudate, and the left inferior parietal lobules. Results suggest that FMI may alter some brain areas of the DMN, above and beyond FM. However, future work will need to investigate these results further by controlling for chronic insomnia only before conclusions can be made regarding the effect of FMI comorbidity on the DMN. PMID:26648751

  2. Sleep is associated with task-negative brain activity in fibromyalgia participants with comorbid chronic insomnia

    PubMed Central

    Vatthauer, Karlyn E; Craggs, Jason G; Robinson, Michael E; Staud, Roland; Berry, Richard B; Perlstein, William M; McCrae, Christina S

    2015-01-01

    Patients with chronic pain exhibit altered default mode network (DMN) activity. This preliminary project questioned whether comorbid disease states are associated with further brain alterations. Thirteen women with fibromyalgia (FM) only and 26 women with fibromyalgia with comorbid chronic insomnia (FMI) underwent a single night of ambulatory polysomnography and completed a sleep diary each morning for 14 days prior to performing a neuroimaging protocol. Novel imaging analyses were utilized to identify regions associated with significantly disordered sleep that were more active in task-negative periods than task-oriented periods in participants with FMI, when compared to participants with FM. It was hypothesized that core DMN areas (ie, cingulate cortex, inferior parietal lobule, medial prefrontal cortex, medial temporal cortex, precuneus) would exhibit increased activity during task-negative periods. Analyses revealed that significantly disordered sleep significantly contributed to group differences in the right cingulate gyrus, left lentiform nucleus, left anterior cingulate, left superior gyrus, medial frontal gyrus, right caudate, and the left inferior parietal lobules. Results suggest that FMI may alter some brain areas of the DMN, above and beyond FM. However, future work will need to investigate these results further by controlling for chronic insomnia only before conclusions can be made regarding the effect of FMI comorbidity on the DMN. PMID:26648751

  3. Theta-Modulated Gamma-Band Synchronization Among Activated Regions During a Verb Generation Task

    PubMed Central

    Doesburg, Sam M.; Vinette, Sarah A.; Cheung, Michael J.; Pang, Elizabeth W.

    2012-01-01

    Expressive language is complex and involves processing within a distributed network of cortical regions. Functional MRI and magnetoencephalography (MEG) have identified brain areas critical for expressive language, but how these regions communicate across the network remains poorly understood. It is thought that synchronization of oscillations between neural populations, particularly at a gamma rate (>30 Hz), underlies functional integration within cortical networks. Modulation of gamma rhythms by theta-band oscillations (4–8 Hz) has been proposed as a mechanism for the integration of local cell coalitions into large-scale networks underlying cognition and perception. The present study tested the hypothesis that these oscillatory mechanisms of functional integration were present within the expressive language network. We recorded MEG while subjects performed a covert verb generation task. We localized activated cortical regions using beamformer analysis, calculated inter-regional phase locking between activated areas, and measured modulation of inter-regional gamma synchronization by theta phase. The results show task-dependent gamma-band synchronization among regions activated during the performance of the verb generation task, and we provide evidence that these transient and periodic instances of high-frequency connectivity were modulated by the phase of cortical theta oscillations. These findings suggest that oscillatory synchronization and cross-frequency interactions are mechanisms for functional integration among distributed brain areas supporting expressive language processing. PMID:22707946

  4. Oscillatory cortical activity during a motor task in a deafferented patient.

    PubMed

    Patino, Luis; Chakarov, Vihren; Schulte-Mönting, Jürgen; Hepp-Reymond, Marie-Claude; Kristeva, Rumyana

    2006-07-01

    Little is known about the influence of the afferent peripheral feedback on the sensorimotor cortex activation. To answer this open question we investigated the alpha and beta band task-related spectral power decreases (TRPow) in the deafferented patient G.L. and compared the results to those of six healthy subjects. The patient has been deafferented up to the nose for 24 years but her motor fibers are unaffected and she can perform complex motor tasks under visual control. We recorded EEG (58 scalp positions) as well as the exerted force during a visuomotor task. The subjects had to maintain in precision grip an isometric force at 15% of the maximal voluntary contraction. In the patient we found a significantly higher alpha band spectral power during rest and larger alpha TRPow decreases during the motor task when compared to the healthy subjects' data. In contrast, we did not observe any significant differences between patient and controls for the beta band TRPow. The results indicate an altered functional alpha band network state in the patient, probably due to the chronic deafferentation leading to a deep 'idling' state of the contralateral sensorimotor area.

  5. Evaluating Reverse Speech as a Control Task with Language-Related Gamma Activity on Electrocorticography

    PubMed Central

    Brown, Erik C; Muzik, Otto; Rothermel, Robert; Matsuzaki, Naoyuki; Juhász, Csaba; Shah, Aashit K; Atkinson, Marie D; Fuerst, Darren; Mittal, Sandeep; Sood, Sandeep; Diwadkar, Vaibhav A; Asano, Eishi

    2012-01-01

    Reverse speech has often been used as a control task in brain-mapping studies of language utilizing various non-invasive modalities. The rationale is that reverse speech is comparable to forward speech in terms of auditory characteristics, while omitting the linguistic components. Thus, it may control for non-language auditory functions. This finds some support in fMRI studies indicating that reverse speech resulted in less blood-oxygen-level-dependent (BOLD) signal intensity in perisylvian regions than forward speech. We attempted to externally validate a reverse speech control task using intracranial electrocorticography (ECoG) in eight patients with intractable focal epilepsy. We studied adolescent and adult patients who underwent extraoperative ECoG prior to resective epilepsy surgery. All patients received an auditory language task during ECoG recording. Patients were presented 115 audible question stimuli, including 30 reverse speech trials. Reverse speech trials more strongly engaged bilateral superior temporal sites than did the corresponding forward speech trials. Forward speech trials elicited larger gamma-augmentation at frontal lobe sites not attributable to sensorimotor function. Other temporal and frontal sites of significant augmentation showed no significant difference between reverse and forward speech. Thus, we failed to validate reported evidence of weaker activation of temporal neocortices during reverse compared to forward speech. Superior temporal lobe engagement may indicate increased attention to reverse speech. Reverse speech does not appear to be a suitable task for the control of non-language auditory functions on ECoG. PMID:22387167

  6. An experimental evaluation of the Sternberg task as a workload metric for helicopter Flight Handling Qualities (FHQ) research

    NASA Technical Reports Server (NTRS)

    Hemingway, J. C.

    1984-01-01

    The objective was to determine whether the Sternberg item-recognition task, employed as a secondary task measure of spare mental capacity for flight handling qualities (FHQ) simulation research, could help to differentiate between different flight-control conditions. FHQ evaluations were conducted on the Vertical Motion Simulator at Ames Research Center to investigate different primary flight-control configurations, and selected stability and control augmentation levels for helicopters engaged in low-level flight regimes. The Sternberg task was superimposed upon the primary flight-control task in a balanced experimental design. The results of parametric statistical analysis of Sternberg secondary task data failed to support the continued use of this task as a measure of pilot workload. In addition to the secondary task, subjects provided Cooper-Harper pilot ratings (CHPR) and responded to workload questionnaire. The CHPR data also failed to provide reliable statistical discrimination between FHQ treatment conditions; some insight into the behavior of the secondary task was gained from the workload questionnaire data.

  7. Prefrontal Cortex Activation Upon a Demanding Virtual Hand-Controlled Task: A New Frontier for Neuroergonomics

    PubMed Central

    Carrieri, Marika; Petracca, Andrea; Lancia, Stefania; Basso Moro, Sara; Brigadoi, Sabrina; Spezialetti, Matteo; Ferrari, Marco; Placidi, Giuseppe; Quaresima, Valentina

    2016-01-01

    Functional near-infrared spectroscopy (fNIRS) is a non-invasive vascular-based functional neuroimaging technology that can assess, simultaneously from multiple cortical areas, concentration changes in oxygenated-deoxygenated hemoglobin at the level of the cortical microcirculation blood vessels. fNIRS, with its high degree of ecological validity and its very limited requirement of physical constraints to subjects, could represent a valid tool for monitoring cortical responses in the research field of neuroergonomics. In virtual reality (VR) real situations can be replicated with greater control than those obtainable in the real world. Therefore, VR is the ideal setting where studies about neuroergonomics applications can be performed. The aim of the present study was to investigate, by a 20-channel fNIRS system, the dorsolateral/ventrolateral prefrontal cortex (DLPFC/VLPFC) in subjects while performing a demanding VR hand-controlled task (HCT). Considering the complexity of the HCT, its execution should require the attentional resources allocation and the integration of different executive functions. The HCT simulates the interaction with a real, remotely-driven, system operating in a critical environment. The hand movements were captured by a high spatial and temporal resolution 3-dimensional (3D) hand-sensing device, the LEAP motion controller, a gesture-based control interface that could be used in VR for tele-operated applications. Fifteen University students were asked to guide, with their right hand/forearm, a virtual ball (VB) over a virtual route (VROU) reproducing a 42 m narrow road including some critical points. The subjects tried to travel as long as possible without making VB fall. The distance traveled by the guided VB was 70.2 ± 37.2 m. The less skilled subjects failed several times in guiding the VB over the VROU. Nevertheless, a bilateral VLPFC activation, in response to the HCT execution, was observed in all the subjects. No correlation was found

  8. Prefrontal Cortex Activation Upon a Demanding Virtual Hand-Controlled Task: A New Frontier for Neuroergonomics.

    PubMed

    Carrieri, Marika; Petracca, Andrea; Lancia, Stefania; Basso Moro, Sara; Brigadoi, Sabrina; Spezialetti, Matteo; Ferrari, Marco; Placidi, Giuseppe; Quaresima, Valentina

    2016-01-01

    Functional near-infrared spectroscopy (fNIRS) is a non-invasive vascular-based functional neuroimaging technology that can assess, simultaneously from multiple cortical areas, concentration changes in oxygenated-deoxygenated hemoglobin at the level of the cortical microcirculation blood vessels. fNIRS, with its high degree of ecological validity and its very limited requirement of physical constraints to subjects, could represent a valid tool for monitoring cortical responses in the research field of neuroergonomics. In virtual reality (VR) real situations can be replicated with greater control than those obtainable in the real world. Therefore, VR is the ideal setting where studies about neuroergonomics applications can be performed. The aim of the present study was to investigate, by a 20-channel fNIRS system, the dorsolateral/ventrolateral prefrontal cortex (DLPFC/VLPFC) in subjects while performing a demanding VR hand-controlled task (HCT). Considering the complexity of the HCT, its execution should require the attentional resources allocation and the integration of different executive functions. The HCT simulates the interaction with a real, remotely-driven, system operating in a critical environment. The hand movements were captured by a high spatial and temporal resolution 3-dimensional (3D) hand-sensing device, the LEAP motion controller, a gesture-based control interface that could be used in VR for tele-operated applications. Fifteen University students were asked to guide, with their right hand/forearm, a virtual ball (VB) over a virtual route (VROU) reproducing a 42 m narrow road including some critical points. The subjects tried to travel as long as possible without making VB fall. The distance traveled by the guided VB was 70.2 ± 37.2 m. The less skilled subjects failed several times in guiding the VB over the VROU. Nevertheless, a bilateral VLPFC activation, in response to the HCT execution, was observed in all the subjects. No correlation was found

  9. Relating practitioner needs to research activities

    NASA Technical Reports Server (NTRS)

    Feather, M. S.; Menzies, T.; Connelly, J. R.

    2003-01-01

    We present an approach to matching needs (practioner requirements) to solutions (researcher activities). A taxonomical classification scheme acts as intermediary between needs and activities. Expert practitioners exprss their needs in terms of this taxonomy. Researchers express their activities in the same terms. A decision support tool is used to assist in the combination and study of their expressions of needs and activities.

  10. Modulation of Brain Activity during a Stroop Inhibitory Task by the Kind of Cognitive Control Required

    PubMed Central

    Grandjean, Julien; D’Ostilio, Kevin; Phillips, Christophe; Balteau, Evelyne; Degueldre, Christian; Luxen, André; Maquet, Pierre; Salmon, Eric; Collette, Fabienne

    2012-01-01

    This study used a proportion congruency manipulation in the Stroop task in order to investigate, at the behavioral and brain substrate levels, the predictions derived from the Dual Mechanisms of Control (DMC) account of two distinct modes of cognitive control depending on the task context. Three experimental conditions were created that varied the proportion congruency: mostly incongruent (MI), mostly congruent (MC), and mostly neutral (MN) contexts. A reactive control strategy, which corresponds to transient interference resolution processes after conflict detection, was expected for the rare conflicting stimuli in the MC context, and a proactive strategy, characterized by a sustained task-relevant focus prior to the occurrence of conflict, was expected in the MI context. Results at the behavioral level supported the proactive/reactive distinction, with the replication of the classic proportion congruent effect (i.e., less interference and facilitation effects in the MI context). fMRI data only partially supported our predictions. Whereas reactive control for incongruent trials in the MC context engaged the expected fronto-parietal network including dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex, proactive control in the MI context was not associated with any sustained lateral prefrontal cortex activations, contrary to our hypothesis. Surprisingly, incongruent trials in the MI context elicited transient activation in common with incongruent trials in the MC context, especially in DLPFC, superior parietal lobe, and insula. This lack of sustained activity in MI is discussed in reference to the possible involvement of item-specific rather than list-wide mechanisms of control in the implementation of a high task-relevant focus. PMID:22911806

  11. Modulation of brain activity during a Stroop inhibitory task by the kind of cognitive control required.

    PubMed

    Grandjean, Julien; D'Ostilio, Kevin; Phillips, Christophe; Balteau, Evelyne; Degueldre, Christian; Luxen, André; Maquet, Pierre; Salmon, Eric; Collette, Fabienne

    2012-01-01

    This study used a proportion congruency manipulation in the Stroop task in order to investigate, at the behavioral and brain substrate levels, the predictions derived from the Dual Mechanisms of Control (DMC) account of two distinct modes of cognitive control depending on the task context. Three experimental conditions were created that varied the proportion congruency: mostly incongruent (MI), mostly congruent (MC), and mostly neutral (MN) contexts. A reactive control strategy, which corresponds to transient interference resolution processes after conflict detection, was expected for the rare conflicting stimuli in the MC context, and a proactive strategy, characterized by a sustained task-relevant focus prior to the occurrence of conflict, was expected in the MI context. Results at the behavioral level supported the proactive/reactive distinction, with the replication of the classic proportion congruent effect (i.e., less interference and facilitation effects in the MI context). fMRI data only partially supported our predictions. Whereas reactive control for incongruent trials in the MC context engaged the expected fronto-parietal network including dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex, proactive control in the MI context was not associated with any sustained lateral prefrontal cortex activations, contrary to our hypothesis. Surprisingly, incongruent trials in the MI context elicited transient activation in common with incongruent trials in the MC context, especially in DLPFC, superior parietal lobe, and insula. This lack of sustained activity in MI is discussed in reference to the possible involvement of item-specific rather than list-wide mechanisms of control in the implementation of a high task-relevant focus. PMID:22911806

  12. Simultaneous EEG-fMRI Reveals a Temporal Cascade of Task-Related and Default-Mode Activations During a Simple Target Detection Task

    PubMed Central

    Walz, Jennifer M.; Goldman, Robin I.; Carapezza, Michael; Muraskin, Jordan; Brown, Truman R.; Sajda, Paul

    2013-01-01

    Focused attention continuously and inevitably fluctuates, and to completely understand the mechanisms responsible for these modulations it is necessary to localize the brain regions involved. During a simple visual oddball task, neural responses measured by electroencephalography (EEG) modulate primarily with attention, but source localization of the correlates is a challenge. In this study we use single-trial analysis of simultaneously-acquired scalp EEG and functional magnetic resonance image (fMRI) data to investigate the blood oxygen level dependent (BOLD) correlates of modulations in task-related attention, and we unravel the temporal cascade of these transient activations. We hypothesize that activity in brain regions associated with various task-related cognitive processes modulates with attention, and that their involvements occur transiently in a specific order. We analyze the fMRI BOLD signal by first regressing out the variance linked to observed stimulus and behavioral events. We then correlate the residual variance with the trial-to-trial variation of EEG discriminating components for identical stimuli, estimated at a sequence of times during a trial. Post-stimulus and early in the trial, we find activations in right-lateralized frontal regions and lateral occipital cortex, areas that are often linked to task-dependent processes, such as attentional orienting, and decision certainty. After the behavioral response we see correlates in areas often associated with the default-mode network and introspective processing, including precuneus, angular gyri, and posterior cingulate cortex. Our results demonstrate that during simple tasks both task-dependent and default-mode networks are transiently engaged, with a distinct temporal ordering and millisecond timescale. PMID:23962956

  13. ECoG gamma activity during a language task: differentiating expressive and receptive speech areas

    PubMed Central

    Yoon, Hyun-Ah; Castelle, Michael; Edgar, J. Christopher; Biassou, Nadia M.; Frim, David M.; Spire, Jean-Paul; Kohrman, Michael H.

    2008-01-01

    Electrocorticographic (ECoG) spectral patterns obtained during language tasks from 12 epilepsy patients (age: 12–44 years) were analysed in order to identify and characterize cortical language areas. ECoG from 63 subdural electrodes (500 Hz/channel) chronically implanted over frontal, parietal and temporal lobes were examined. Two language tasks were performed. During the first language task, patients listened to a series of 50 words preceded by warning tones, and were asked to repeat each word. During a second memory task, subjects heard the 50 words from the first task randomly mixed with 50 new words and were asked to repeat the word only if it was a new word. Increases in ECoG gamma power (70–100 Hz) were observed in response to hearing tones (primary auditory cortex), hearing words (posterior temporal and parietal cortex) and repeating words (lateral frontal and anterior parietal cortex). These findings were compared to direct electrical stimulation and separate analysis of ECoG gamma changes during spontaneous inter-personal conversations. The results indicate that high-frequency ECoG reliably differentiates cortical areas associated with receptive and expressive speech processes for individual patients. Compared to listening to words, greater frontal lobe and decreased temporal lobe gamma activity was observed while speaking. The data support the concept of distributed functionally specific language modules interacting to serve receptive and expressive speech, with frontal lobe ‘corollary discharges’ suppressing low-level receptive cortical language areas in the temporal lobe during speaking. PMID:18669510

  14. The SEDIBUD (Sediment Budgets in Cold Environments) Programme: Current activities and future key tasks

    NASA Astrophysics Data System (ADS)

    Beylich, A. A.; Lamoureux, S. F.; Decaulne, A.

    2012-04-01

    Projected climate change in cold regions is expected to alter melt season duration and intensity, along with the number of extreme rainfall events, total annual precipitation and the balance between snowfall and rainfall. Similarly, changes to the thermal balance are expected to reduce the extent of permafrost and seasonal ground frost and increase active layer depths. These effects will undoubtedly change surface environments in cold regions and alter the fluxes of sediments, nutrients and solutes, but the absence of quantitative data and coordinated process monitoring and analysis to understand the sensitivity of the Earth surface environment is acute in cold climate environments. The International Association of Geomorphologists (I.A.G./A.I.G.)SEDIBUD (Sediment Budgets in Cold Environments) Programme was formed in 2005 to address this existing key knowledge gap. SEDIBUD currently has about 400 members worldwide and the Steering Committee of this international programme is composed of ten scientists from eight different countries: Achim A. Beylich (Chair) (Norway), Armelle Decaulne (Secretary) (France), John C. Dixon (USA), Scott F. Lamoureux (Vice-Chair) (Canada), John F. Orwin (Canada), Jan-Christoph Otto (Austria), Irina Overeem (USA), Thorsteinn Saemundsson (Iceland), Jeff Warburton (UK), Zbigniew Zwolinski (Poland). The central research question of this global group of scientists is to: Assess and model the contemporary sedimentary fluxes in cold climates, with emphasis on both particulate and dissolved components. Initially formed as European Science Foundation (ESF) Network SEDIFLUX (2004-2006), SEDIBUD has further expanded to a global group of researchers with field research sites located in polar and alpine regions in the northern and southern hemisphere. Research carried out at each of the close to 50 defined SEDIBUD key test sites varies by programme, logistics and available resources, but typically represent interdisciplinary collaborations of

  15. OCLC Research: 2012 Activity Report

    ERIC Educational Resources Information Center

    OCLC Online Computer Library Center, Inc., 2013

    2013-01-01

    The mission of the Online Computer Library Center (OCLC) Research is to expand knowledge that advances OCLC's public purposes of furthering access to the world's information and reducing library costs. OCLC Research is dedicated to three roles: (1)To act as a community resource for shared research and development (R&D); (2) To provide advanced…

  16. Locomotion and Task Demands Differentially Modulate Thalamic Audiovisual Processing during Active Search.

    PubMed

    Williamson, Ross S; Hancock, Kenneth E; Shinn-Cunningham, Barbara G; Polley, Daniel B

    2015-07-20

    Active search is a ubiquitous goal-driven behavior wherein organisms purposefully investigate the sensory environment to locate a target object. During active search, brain circuits analyze a stream of sensory information from the external environment, adjusting for internal signals related to self-generated movement or "top-down" weighting of anticipated target and distractor properties. Sensory responses in the cortex can be modulated by internal state, though the extent and form of modulation arising in the cortex de novo versus an inheritance from subcortical stations is not clear. We addressed this question by simultaneously recording from auditory and visual regions of the thalamus (MG and LG, respectively) while mice used dynamic auditory or visual feedback to search for a hidden target within an annular track. Locomotion was associated with strongly suppressed responses and reduced decoding accuracy in MG but a subtle increase in LG spiking. Because stimuli in one modality provided critical information about target location while the other served as a distractor, we could also estimate the importance of task relevance in both thalamic subdivisions. In contrast to the effects of locomotion, we found that LG responses were reduced overall yet decoded stimuli more accurately when vision was behaviorally relevant, whereas task relevance had little effect on MG responses. This double dissociation between the influences of task relevance and movement in MG and LG highlights a role for extrasensory modulation in the thalamus but also suggests key differences in the organization of modulatory circuitry between the auditory and visual pathways.

  17. Arousal Modulates Activity in the Medial Temporal Lobe during a Short-Term Relational Memory Task.

    PubMed

    Thoresen, Christian; Jensen, Jimmy; Sigvartsen, Niels Petter B; Bolstad, Ingeborg; Server, Andres; Nakstad, Per H; Andreassen, Ole A; Endestad, Tor

    2011-01-01

    This study investigated the effect of arousal on short-term relational memory and its underlying cortical network. Seventeen healthy participants performed a picture by location, short-term relational memory task using emotional pictures. Functional magnetic resonance imaging was used to measure the blood-oxygenation-level dependent signal relative to task. Subjects' own ratings of the pictures were used to obtain subjective arousal ratings. Subjective arousal was found to have a dose-dependent effect on activations in the prefrontal cortex, amygdala, hippocampus, and in higher order visual areas. Serial position analyses showed that high arousal trials produced a stronger primacy and recency effect than low arousal trials. The results indicate that short-term relational memory may be facilitated by arousal and that this may be modulated by a dose-response function in arousal-driven neuronal regions.

  18. PWC - PAIRWISE COMPARISON SOFTWARE: SOFTWARE PROGRAM FOR PAIRWISE COMPARISON TASK FOR PSYCHOMETRIC SCALING AND COGNITIVE RESEARCH

    NASA Technical Reports Server (NTRS)

    Ricks, W. R.

    1994-01-01

    PWC is used for pair-wise comparisons in both psychometric scaling techniques and cognitive research. The cognitive tasks and processes of a human operator of automated systems are now prominent considerations when defining system requirements. Recent developments in cognitive research have emphasized the potential utility of psychometric scaling techniques, such as multidimensional scaling, for representing human knowledge and cognitive processing structures. Such techniques involve collecting measurements of stimulus-relatedness from human observers. When data are analyzed using this scaling approach, an n-dimensional representation of the stimuli is produced. This resulting representation is said to describe the subject's cognitive or perceptual view of the stimuli. PWC applies one of the many techniques commonly used to acquire the data necessary for these types of analyses: pair-wise comparisons. PWC administers the task, collects the data from the test subject, and formats the data for analysis. It therefore addresses many of the limitations of the traditional "pen-and-paper" methods. By automating the data collection process, subjects are prevented from going back to check previous responses, the possibility of erroneous data transfer is eliminated, and the burden of the administration and taking of the test is eased. By using randomization, PWC ensures that subjects see the stimuli pairs presented in random order, and that each subject sees pairs in a different random order. PWC is written in Turbo Pascal v6.0 for IBM PC compatible computers running MS-DOS. The program has also been successfully compiled with Turbo Pascal v7.0. A sample executable is provided. PWC requires 30K of RAM for execution. The standard distribution medium for this program is a 5.25 inch 360K MS-DOS format diskette. Two electronic versions of the documentation are included on the diskette: one in ASCII format and one in MS Word for Windows format. PWC was developed in 1993.

  19. Activation of the caudal anterior cingulate cortex due to task-related interference in an auditory Stroop paradigm.

    PubMed

    Haupt, Sven; Axmacher, Nikolai; Cohen, Michael X; Elger, Christian E; Fell, Juergen

    2009-09-01

    Successful information processing requires the focusing of attention on a certain stimulus property and the simultaneous suppression of irrelevant information. The Stroop task is a useful paradigm to study such attentional top-down control in the presence of interference. Here, we investigated the neural correlates of an auditory Stroop task using fMRI. Subjects focused either on tone pitch (relatively high or low; phonetic task) or on the meaning of a spoken word (high/low/good; semantic task), while ignoring the other stimulus feature. We differentiated between task-related (phonetic incongruent vs. semantic incongruent) and sensory-level interference (phonetic incongruent vs. phonetic congruent). Task-related interference activated similar regions as in visual Stroop tasks, including the anterior cingulate cortex (ACC) and the presupplementary motor-area (pre-SMA). More specifically, we observed that the very caudal/posterior part of the ACC was activated and not the dorsal/anterior region. Because identical stimuli but different task demands are compared in this contrast, it reflects conflict at a relatively high processing level. A more conventional contrast between incongruent and congruent phonetic trials was associated with a different cluster in the pre-SMA/ACC which was observed in a large number of previous studies. Finally, functional connectivity analysis revealed that activity within the regions activated in the phonetic incongruent vs. semantic incongruent contrast was more strongly interrelated during semantically vs. phonetically incongruent trials. Taken together, we found (besides activation of regions well-known from visual Stroop tasks) activation of the very caudal and posterior part of the ACC due to task-related interference in an auditory Stroop task. PMID:19180558

  20. Congruency effects in the letter search task: semantic activation in the absence of priming.

    PubMed

    Hutchison, Keith A; Bosco, Frank A

    2007-04-01

    Semantic priming is typically eliminated when participants perform a letter search on the prime, suggesting that semantic activation is conditional upon one's attentional goals. However, in such studies, semantic activation (or the lack thereof) is not measured during the letter search task itself but, instead, is inferred on the basis of the responses given to a later target. In the present study, direct online evidence for semanticactivation was tested using words whose meaning should bias either a positive or a negative response (e.g.,present vs. absent). In Experiment 1, a semantic congruency effect was obtained, with faster responses when the word meaning matched the required response. Experiment 2 replicated the congruency effect while, simultaneously, showing the elimination of semantic priming. It is concluded that letter search does not affect the initiation of semantic activation. Possible accounts for the elimination of priming following letter search include activation-based suppression and transfer-inappropriate processing.

  1. Chronic Low Back Pain in Women: Muscle Activation during Task Performance

    PubMed Central

    Santos, Fernanda G; Carmo, Carolina M; Fracini, América C; Pereira, Rita R P; Takara, Kelly S; Tanaka, Clarice

    2014-01-01

    [Purpose] The aim of this study was to compare the activities of the trunk and hip muscles in chronic low back pain (CLBP) women and asymptomatic subjects during the kneeling to half-kneeling task. [Subjects] Twenty-nine CLBP women and thirty asymptomatic subjects (C) participated in this study. [Methods] Electromyography activity (EMG) of the obliquus internus abdominis (OI), the lumbar erector spinae (LES) and the gluteus medius (GM) muscles was recorded bilaterally. The peak amplitude, the time of peak amplitude and the integrated linear envelope EMG for each muscle were obtained. [Results] The C group bilateral OI and GM muscles displayed higher peak amplitudes and earlier times of peak amplitude. They also had higher integrated linear envelope EMG values. The CLBP group bilateral LES muscles had higher peak amplitudes and earlier times of peak amplitude. They also showed an increased integrated linear envelope EMG values. [Conclusion] The CLBP women activate the LES muscles in the kneeling to half-kneeling task, showing different patterns of motor planning activity. PMID:24409022

  2. Type 1 Diabetes Modifies Brain Activation in Young Patients While Performing Visuospatial Working Memory Tasks

    PubMed Central

    Gallardo-Moreno, Geisa B.; González-Garrido, Andrés A.; Gudayol-Ferré, Esteban; Guàrdia-Olmos, Joan

    2015-01-01

    In recent years, increasing attention has been paid to the effects of Type 1 Diabetes (T1D) on cognitive functions. T1D onset usually occurs during childhood, so it is possible that the brain could be affected during neurodevelopment. We selected young patients of normal intelligence with T1D onset during neurodevelopment, no complications from diabetes, and adequate glycemic control. The purpose of this study was to compare the neural BOLD activation pattern in a group of patients with T1D versus healthy control subjects while performing a visuospatial working memory task. Sixteen patients and 16 matched healthy control subjects participated. There was no significant statistical difference in behavioral performance between the groups, but, in accordance with our hypothesis, results showed distinct brain activation patterns. Control subjects presented the expected activations related to the task, whereas the patients had greater activation in the prefrontal inferior cortex, basal ganglia, posterior cerebellum, and substantia nigra. These different patterns could be due to compensation mechanisms that allow them to maintain a behavioral performance similar to that of control subjects. PMID:26266268

  3. Neural Activation in Humans during a Simple Motor Task Differs between BDNF Polymorphisms

    PubMed Central

    Cárdenas-Morales, Lizbeth; Grön, Georg; Sim, Eun-Jin; Stingl, Julia C.; Kammer, Thomas

    2014-01-01

    The BDNF Val66Met polymorphism has been linked to decreased synaptic plasticity involved in motor learning tasks. We investigated whether individual differences in this polymorphism may promote differences in neural activity during a two-alternative forced-choice motor performance. In two separate sessions, the BOLD signal from 22 right-handed healthy men was measured during button presses with the left and right index finger upon visual presentation of an arrow. 11 men were Val66Val carriers (ValVal group), the other 11 men carried either the Val66Met or the Met66Met polymorphism (Non-ValVal group). Reaction times, resting and active motor thresholds did not differ between ValVal and Non-ValVal groups. Compared to the ValVal group the Non-ValVal group showed significantly higher BOLD signals in the right SMA and motor cingulate cortex during motor performance. This difference was highly consistent for both hands and across all four sessions. Our finding suggests that this BDNF polymorphism may not only influence complex performance during motor learning but is already associated with activation differences during rather simple motor tasks. The higher BOLD signal observed in Non-ValVal subjects suggests the presence of cumulative effects of the polymorphism on the motor system, and may reflect compensatory functional activation mediating equal behavioral performance between groups. PMID:24828051

  4. Age- and sex-related differences for electromyography gaps during daily activity and a discrete task.

    PubMed

    Harwood, B; Edwards, D L; Jakobi, J M

    2011-05-01

    Temporal patterns of quiescent electromyography termed 'gaps' were investigated in young and old men and women for a discrete task and daily activity. Gaps in women (1.3±3.2) and old adults (1.5±3.4) were fewer compared with men (4.7±6.7) and young adults (4.6±6.9) for the discrete task (p<0.001). Gap duration was shorter for women (0.1±0.2s) and old adults (0.1±0.3s) compared with men (0.2±0.3s) and young adults (0.2±0.2s) (p<0.01). For daily activity, gap number was similar with age, but gap duration and percentage of total time occupied by gaps were less in old compared with young adults (50%), and in women compared with men (43%) (p<0.001). Results suggest gap activity is sensitive to type and duration of activity and that old adults and women demonstrate less quiescent electromyography than young adults and men.

  5. Ventrolateral prefrontal activation during a N-back task assessed with multichannel functional near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhou, Yuan; Zhu, Ye; Jiang, Tianzi

    2007-05-01

    Functional near-infrared spectroscopy (fNIRS) has been used to investigate the changes in the concentration of oxygenated (O2Hb) and deoxygenated (HHb) hemoglobin in brain issue during several cognitive tasks. In the present study, by means of multichannel dual wavelength light-emitting diode continuous-wave (CW) NIRS, we investigated the blood oxygenation changes of prefrontal cortex in 18 healthy subjects while performing a verbal n-back task (0-back and 2-back), which has been rarely investigated by fNIRS. Compared to the 0-back task (control task), we found a significant increase of O2Hb and total amount of hemoglobin (THb) in left and right ventrolateral prefrontal cortex (VLPFC) during the execution of the 2-back task compared to the 0-back task (p<0.05, FDR corrected). This result is consistent with the previous functional neuroimaging studies that have found the VLPFC activation related to verbal working memory. However, we found no significant hemisphere dominance. In addition, the effects of gender and its interaction with task performance on O2Hb concentration change were suggested in the present study. Our findings not only confirm that multichannel fNIRS is suitable to detect spatially specific activation during the performance of cognitive tasks; but also suggest that it should be cautious of gender-dependent difference in cerebral activation when interpreting the fNIRS data during cognitive tasks.

  6. Semantic Support Environment for Research Activity

    ERIC Educational Resources Information Center

    Ismail, Maizatul Akmar; Yaacob, Mashkuri; Kareem, Sameem Abdul

    2008-01-01

    Scholarly activities are a collection of academic related activities such as research, teaching and consultation work which result in research outputs such as journals, theses and articles in proceedings. The output will then be disseminated to researchers all over the world by means of the WWW. The four pillars of this scholarship i.e. discovery,…

  7. Effects of active pause pattern of surface electromyographic activity among subjects performing monotonous tasks: A systematic review.

    PubMed

    Januario, Leticia Bergamin; Moreira, Roberta de Fátima Carreira; Cid, Marina Machado; Samani, Afshin; Madeleine, Pascal; Oliveira, Ana Beatriz

    2016-10-01

    Active pauses have shown potentially beneficial effects to increase the variability of the electrical activation pattern of muscles. However, there is a lack of consensus as to how to design and implement those pauses and the processing methods of surface electromyography (EMG) data when evaluating low-level monotonous tasks. The aim of this systematic review was to synthesize the evidences regarding the way which active pauses have been applied, and the methods used to investigate the related EMG changes. PubMed-MEDLINE, Embase, Web of Science, Lilacs, Ebsco, and Scopus databases were searched. Two authors independently extracted data from the primary studies. The methodological quality was assessed using a list from van der Windt et al. (2000), and the level of evidence was synthesized through GRADE. The ISEK guideline for reporting EMG data was also applied as a checklist. Fifteen studies were included - 14 with high methodological quality. In general, active pauses were able to change the level of EMG activity in monotonous tasks. The level of evidence through GRADE was very low for all EMG processing methods, except RMS which was low. A vast heterogeneity concerning the methods applied to analyze EMG data contributed to decrease the quality of evidence synthesis, and the findings need to be carefully considered. The GRADE approach and the ISEK guideline contributed to identify important flaws in the literature. Future studies investigating active pauses in longitudinal studies and following the standard for recording and reporting EMG data care are warranted.

  8. Supporting Student Research Group Activities.

    ERIC Educational Resources Information Center

    Lopatin, Dennis E.

    1993-01-01

    This discussion describes methods that foster a healthy Student Research Group (SRG) and permits it to fulfill its responsibility in the development of the student researcher. The model used in the discussion is that of the University of Michigan School of Dentistry SRG. (GLR)

  9. 78 FR 10636 - Task Force on Research on Violence Against American Indian and Alaska Native Women; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-14

    ... Force on Research on Violence Against American Indian and Alaska Native Women; Meeting AGENCY: Office on Violence Against Women, United States Department of Justice. ACTION: Notice of Meeting. SUMMARY: This... Research on Violence Against American Indian and Alaska Native Women(hereinafter ``the Task Force'')....

  10. Using Activity Schedules to Increase On-Task Behavior in Children at Risk for Attention-Deficit/Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Cirelli, Christe A.; Sidener, Tina M.; Reeve, Kenneth F.; Reeve, Sharon A.

    2016-01-01

    The effects of activity schedules on on-task and on-schedule behavior were assessed with two boys at risk for attention-deficit/hyperactivity disorder (ADHD) and referred by their public school teachers as having difficulty during independent work time. On-task behavior increased for both participants after two training sessions. Teachers, peers,…

  11. Monte Carlo reference data sets for imaging research: Executive summary of the report of AAPM Research Committee Task Group 195.

    PubMed

    Sechopoulos, Ioannis; Ali, Elsayed S M; Badal, Andreu; Badano, Aldo; Boone, John M; Kyprianou, Iacovos S; Mainegra-Hing, Ernesto; McMillan, Kyle L; McNitt-Gray, Michael F; Rogers, D W O; Samei, Ehsan; Turner, Adam C

    2015-10-01

    The use of Monte Carlo simulations in diagnostic medical imaging research is widespread due to its flexibility and ability to estimate quantities that are challenging to measure empirically. However, any new Monte Carlo simulation code needs to be validated before it can be used reliably. The type and degree of validation required depends on the goals of the research project, but, typically, such validation involves either comparison of simulation results to physical measurements or to previously published results obtained with established Monte Carlo codes. The former is complicated due to nuances of experimental conditions and uncertainty, while the latter is challenging due to typical graphical presentation and lack of simulation details in previous publications. In addition, entering the field of Monte Carlo simulations in general involves a steep learning curve. It is not a simple task to learn how to program and interpret a Monte Carlo simulation, even when using one of the publicly available code packages. This Task Group report provides a common reference for benchmarking Monte Carlo simulations across a range of Monte Carlo codes and simulation scenarios. In the report, all simulation conditions are provided for six different Monte Carlo simulation cases that involve common x-ray based imaging research areas. The results obtained for the six cases using four publicly available Monte Carlo software packages are included in tabular form. In addition to a full description of all simulation conditions and results, a discussion and comparison of results among the Monte Carlo packages and the lessons learned during the compilation of these results are included. This abridged version of the report includes only an introductory description of the six cases and a brief example of the results of one of the cases. This work provides an investigator the necessary information to benchmark his/her Monte Carlo simulation software against the reference cases included here

  12. Monte Carlo reference data sets for imaging research: Executive summary of the report of AAPM Research Committee Task Group 195.

    PubMed

    Sechopoulos, Ioannis; Ali, Elsayed S M; Badal, Andreu; Badano, Aldo; Boone, John M; Kyprianou, Iacovos S; Mainegra-Hing, Ernesto; McMillan, Kyle L; McNitt-Gray, Michael F; Rogers, D W O; Samei, Ehsan; Turner, Adam C

    2015-10-01

    The use of Monte Carlo simulations in diagnostic medical imaging research is widespread due to its flexibility and ability to estimate quantities that are challenging to measure empirically. However, any new Monte Carlo simulation code needs to be validated before it can be used reliably. The type and degree of validation required depends on the goals of the research project, but, typically, such validation involves either comparison of simulation results to physical measurements or to previously published results obtained with established Monte Carlo codes. The former is complicated due to nuances of experimental conditions and uncertainty, while the latter is challenging due to typical graphical presentation and lack of simulation details in previous publications. In addition, entering the field of Monte Carlo simulations in general involves a steep learning curve. It is not a simple task to learn how to program and interpret a Monte Carlo simulation, even when using one of the publicly available code packages. This Task Group report provides a common reference for benchmarking Monte Carlo simulations across a range of Monte Carlo codes and simulation scenarios. In the report, all simulation conditions are provided for six different Monte Carlo simulation cases that involve common x-ray based imaging research areas. The results obtained for the six cases using four publicly available Monte Carlo software packages are included in tabular form. In addition to a full description of all simulation conditions and results, a discussion and comparison of results among the Monte Carlo packages and the lessons learned during the compilation of these results are included. This abridged version of the report includes only an introductory description of the six cases and a brief example of the results of one of the cases. This work provides an investigator the necessary information to benchmark his/her Monte Carlo simulation software against the reference cases included here

  13. Neural activity in monkey amygdala during performance of a multisensory operant task.

    PubMed

    Montes-Lourido, Pilar; Vicente, Ana F; Bermudez, Maria A; Gonzalez, Francisco

    2015-09-01

    In this paper, we study the potential involvement of monkey amygdala in the evaluation of value encoding of visual and auditive stimuli associated with reward or no reward. We recorded the activity of 93 extracellular neurons from the monkey right amygdala, while performing a multisensory operant task. The activity of 78 task-related neurons was studied. Of these, 13 neurons (16%) responded to the value of visual stimuli, 22 neurons (28%) responded after the presentation of visual stimuli, 22 neurons (28%) showed an inhibition around the lever-pressing and were classified as action related neurons and 22 neurons (28%) responded after reward delivery. These findings suggest that neurons in the amygdala play a role in encoding value and processing visual information, participate in motor regulation and are sensitive to reward. The activity of these neurons did not change in the evaluation of auditive stimuli. These data support the hypothesis that amygdala neurons are specific to each sensory modality and that different groups of amygdala neurons process visual and auditive information. PMID:26246438

  14. Workshop report and presentations from the Semiconductor Research Corporation-DOE Semiconductor Task Force Workshop

    NASA Astrophysics Data System (ADS)

    The Semiconductor Research Corporation-DOE Semiconductor Task Force Workshop was held in Oak ridge, Tennessee, on November 2-3, 1987. It was to provide a forum for representatives of the national laboratories, DOE, and the semiconductor industry in which to discuss capabilities of the national laboratories which could contribute to the future competitiveness of the US semiconductor industry, to identify specific large and small projects at the national laboratories which would be of direct benefit to the semiconductor industry, and to find ways of implementing these projects. Numerous small projects were identified which would utilize unique capabilities of the national laboratories in advanced ion implantation, plasma processing (including electron cyclotron resonance plasmas), ion and cluster beam deposition, materials characterization, electronic packaging, and laser processing and deposition. Five large-scale candidate projects were identified in synchrotron x-ray lithography, silicon process integration, advanced materials processing science, process analysis and diagnostics, and ultra clean room engineering. The major obstacle to implementing these projects if the lack of appropriate funds to initiate and stimulate interactions between the national laboratories and the semiconductor industry. SEMATECH and the federal government are potential sources of seed funds for these projects. The Semiconductor Research Corporation is ideally suited to interface the semiconductor industry and the national laboratories for many of these interactions.

  15. Effects of Hand Dominance and Postural Selection on Muscle Activities of Virtual Laparoscopic Surgical Training Tasks.

    PubMed

    Huang, Chun-Kai; Boman, Ashley; White, Anthony; Oleynikov, Dmitry; Siu, Ka-Chun

    2016-01-01

    This study investigated how the ergonomic factors, such as hand dominance and postural selection, influenced on surgical performance regarding the changes of muscle activity. Twenty novices performed two virtual laparoscopic surgical training tasks and five target muscle activities were measured. Compared with using dominant hand, surgical skills performance using non-dominant hand increased muscle activities. Muscle fatigue is more likely induced in standing position than sitting position during practice. This study suggests an emerging need to focus on hand dominance during laparoscopic surgical training to address the impact of hand discrepancy on bimanual coordination. It is also important to pay attention on postural selection during training to reduce muscle fatigue, which possibly leads to injuries. PMID:27046567

  16. Goal striving strategies and effort mobilization: When implementation intentions reduce effort-related cardiac activity during task performance.

    PubMed

    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.

  17. Classroom-based high-intensity interval activity improves off-task behaviour in primary school students.

    PubMed

    Ma, Jasmin K; Le Mare, Lucy; Gurd, Brendon J

    2014-12-01

    This study examined the effects of an acute bout of brief, high-intensity interval exercise on off-task classroom behaviour in primary school students. A grade 4 class (n = 24) and a grade 2 class (n = 20) were exposed to either a no-activity break or an active break that consisted of "FUNtervals", a high-intensity interval protocol, on alternating days for 3 weeks. No-activity days consisted of a 10-min inactive break while FUNterval days consisted of a 4-min FUNterval completed within a 10-min break from regular class activities. Off-task behaviour was observed for 50 min after each no-activity/FUNterval break, with the amount of time students spent off-task (motor, passive, and verbal behaviour) being recorded. When comparing no-activity breaks with FUNtervals the grade 4 class demonstrated reductions in both passive (no activity = 29% ± 13% vs. FUNterval = 25% ± 13%, p < 0.05, effect size (ES) = 0.31) and motor (no activity = 31% ± 16% vs. FUNterval = 24% ± 13%, p < 0.01, ES = 0.48) off-task behaviour following FUNtervals. Similarly, in the grade 2 class, passive (no activity = 23% ± 14% vs. FUNterval = 14% ± 10%, p < 0.01, ES = 0.74), verbal (no activity = 8% ± 8% vs. FUNterval = 5% ± 5%, p < 0.05, ES = 0.45), and motor (no activity = 29% ± 17% vs. FUNterval = 14% ± 10%, p < 0.01, ES = 1.076) off-task behaviours were reduced following FUNtervals. In both classrooms the effects of physical activity were greatest in those students demonstrating the highest rates of off-task behaviour on no-activity days. These data demonstrate that very brief high-intensity bouts of exercise can improve off-task behaviour in grade 2 and 4 students, particularly in students with high rates of such behaviour.

  18. Bilateral motor tasks involve more brain regions and higher neural activation than unilateral tasks: an fMRI study.

    PubMed

    Noble, Jeremy W; Eng, Janice J; Boyd, Lara A

    2014-09-01

    Movements that involve simultaneous coordination of muscles of the right and left lower limbs form a large part of our daily activities (e.g., standing, rising from a chair). This study used functional magnetic resonance imaging to determine which brain areas are used to control coordinated lower-limb movements, specifically comparing regions that are activated during bilateral exertions to those performed unilaterally. Plantarflexor exertions were produced at a target force level of 15% of the participants' maximum voluntary contraction, in three conditions, with their right (dominant) foot, with their left foot, and with both feet simultaneously. A voxel-wise analysis determined which regions were active in the bilateral, but not in the unilateral conditions. In addition, a region of interest (ROI) approach was used to determine differences in the percent signal change (PSC) between the conditions within motor areas. The voxel-wise analysis showed a large number of regions (cortical, subcortical, and cerebellar) that were active during the bilateral condition, but not during either unilateral condition. The ROI analysis showed several motor regions with higher activation in the bilateral condition than unilateral conditions; further, the magnitude of bilateral PSC was more than the sum of the two unilateral conditions in several of these regions. We postulate that the greater levels of activation during bilateral exertions may arise from interhemispheric inhibition, as well as from the greater need for motor coordination (e.g., synchronizing the two limbs to activate together) and visual processing (e.g., monitoring of two visual stimuli).

  19. Simultaneous fNIRS and thermal infrared imaging during cognitive task reveal autonomic correlates of prefrontal cortex activity

    NASA Astrophysics Data System (ADS)

    Pinti, Paola; Cardone, Daniela; Merla, Arcangelo

    2015-12-01

    Functional Near Infrared-Spectroscopy (fNIRS) represents a powerful tool to non-invasively study task-evoked brain activity. fNIRS assessment of cortical activity may suffer for contamination by physiological noises of different origin (e.g. heart beat, respiration, blood pressure, skin blood flow), both task-evoked and spontaneous. Spontaneous changes occur at different time scales and, even if they are not directly elicited by tasks, their amplitude may result task-modulated. In this study, concentration changes of hemoglobin were recorded over the prefrontal cortex while simultaneously recording the facial temperature variations of the participants through functional infrared thermal (fIR) imaging. fIR imaging provides touch-less estimation of the thermal expression of peripheral autonomic. Wavelet analysis revealed task-modulation of the very low frequency (VLF) components of both fNIRS and fIR signals and strong coherence between them. Our results indicate that subjective cognitive and autonomic activities are intimately linked and that the VLF component of the fNIRS signal is affected by the autonomic activity elicited by the cognitive task. Moreover, we showed that task-modulated changes in vascular tone occur both at a superficial and at larger depth in the brain. Combined use of fNIRS and fIR imaging can effectively quantify the impact of VLF autonomic activity on the fNIRS signals.

  20. Simultaneous fNIRS and thermal infrared imaging during cognitive task reveal autonomic correlates of prefrontal cortex activity

    PubMed Central

    Pinti, Paola; Cardone, Daniela; Merla, Arcangelo

    2015-01-01

    Functional Near Infrared-Spectroscopy (fNIRS) represents a powerful tool to non-invasively study task-evoked brain activity. fNIRS assessment of cortical activity may suffer for contamination by physiological noises of different origin (e.g. heart beat, respiration, blood pressure, skin blood flow), both task-evoked and spontaneous. Spontaneous changes occur at different time scales and, even if they are not directly elicited by tasks, their amplitude may result task-modulated. In this study, concentration changes of hemoglobin were recorded over the prefrontal cortex while simultaneously recording the facial temperature variations of the participants through functional infrared thermal (fIR) imaging. fIR imaging provides touch-less estimation of the thermal expression of peripheral autonomic. Wavelet analysis revealed task-modulation of the very low frequency (VLF) components of both fNIRS and fIR signals and strong coherence between them. Our results indicate that subjective cognitive and autonomic activities are intimately linked and that the VLF component of the fNIRS signal is affected by the autonomic activity elicited by the cognitive task. Moreover, we showed that task-modulated changes in vascular tone occur both at a superficial and at larger depth in the brain. Combined use of fNIRS and fIR imaging can effectively quantify the impact of VLF autonomic activity on the fNIRS signals. PMID:26632763

  1. Final Report Project Activity Task ORD-FY04-002 Nevada System of Higher Education Quality Assurance Program

    SciTech Connect

    Smiecinski, Amy; Keeler, Raymond; Bertoia, Julie; Mueller, Terry; Roosa, Morris; Roosa, Barbara

    2008-03-07

    implemented the QA program and completed individual research project activities. PIs were also responsible for developing implementing procedures, conducting technical training, assuring that the QA program training was acquired by all task personnel, and participating in monitoring the QA program control for each individual research project activity. This project activity, which was an essential part of the program to enhance the collaborative ongoing research between the NSHE and ORD, was intended to support all quality-affecting activities funded during the five-year period of the cooperative agreement. However, the cooperative agreement was down-graded to non quality-affecting after 4 years.

  2. Classification of autistic individuals and controls using cross-task characterization of fMRI activity

    PubMed Central

    Chanel, Guillaume; Pichon, Swann; Conty, Laurence; Berthoz, Sylvie; Chevallier, Coralie; Grèzes, Julie

    2015-01-01

    Multivariate pattern analysis (MVPA) has been applied successfully to task-based and resting-based fMRI recordings to investigate which neural markers distinguish individuals with autistic spectrum disorders (ASD) from controls. While most studies have focused on brain connectivity during resting state episodes and regions of interest approaches (ROI), a wealth of task-based fMRI datasets have been acquired in these populations in the last decade. This calls for techniques that can leverage information not only from a single dataset, but from several existing datasets that might share some common features and biomarkers. We propose a fully data-driven (voxel-based) approach that we apply to two different fMRI experiments with social stimuli (faces and bodies). The method, based on Support Vector Machines (SVMs) and Recursive Feature Elimination (RFE), is first trained for each experiment independently and each output is then combined to obtain a final classification output. Second, this RFE output is used to determine which voxels are most often selected for classification to generate maps of significant discriminative activity. Finally, to further explore the clinical validity of the approach, we correlate phenotypic information with obtained classifier scores. The results reveal good classification accuracy (range between 69% and 92.3%). Moreover, we were able to identify discriminative activity patterns pertaining to the social brain without relying on a priori ROI definitions. Finally, social motivation was the only dimension which correlated with classifier scores, suggesting that it is the main dimension captured by the classifiers. Altogether, we believe that the present RFE method proves to be efficient and may help identifying relevant biomarkers by taking advantage of acquired task-based fMRI datasets in psychiatric populations. PMID:26793434

  3. Locomotion and task demands differentially modulate thalamic audiovisual processing during active search

    PubMed Central

    Williamson, Ross S.; Hancock, Kenneth E.; Shinn-Cunningham, Barbara G.; Polley, Daniel B.

    2015-01-01

    SUMMARY Active search is a ubiquitous goal-driven behavior wherein organisms purposefully investigate the sensory environment to locate a target object. During active search, brain circuits analyze a stream of sensory information from the external environment, adjusting for internal signals related to self-generated movement or “top-down” weighting of anticipated target and distractor properties. Sensory responses in the cortex can be modulated by internal state [1–9], though the extent and form of modulation arising in the cortex de novo versus an inheritance from subcortical stations is not clear [4, 8–12]. We addressed this question by simultaneously recording from auditory and visual regions of the thalamus (MG and LG, respectively) while mice used dynamic auditory or visual feedback to search for a hidden target within an annular track. Locomotion was associated with strongly suppressed responses and reduced decoding accuracy in MG but a subtle increase in LG spiking. Because stimuli in one modality provided critical information about target location while the other served as a distractor, we could also estimate the importance of task relevance in both thalamic subdivisions. In contrast to the effects of locomotion, we found that LG responses were reduced overall yet decoded stimuli more accurately when vision was behaviorally relevant, whereas task relevance had little effect on MG responses. This double dissociation between the influences of task relevance and movement in MG and LG highlights a role for extrasensory modulation in the thalamus but also suggests key differences in the organization of modulatory circuitry between the auditory and visual pathways. PMID:26119749

  4. Classification of autistic individuals and controls using cross-task characterization of fMRI activity.

    PubMed

    Chanel, Guillaume; Pichon, Swann; Conty, Laurence; Berthoz, Sylvie; Chevallier, Coralie; Grèzes, Julie

    2016-01-01

    Multivariate pattern analysis (MVPA) has been applied successfully to task-based and resting-based fMRI recordings to investigate which neural markers distinguish individuals with autistic spectrum disorders (ASD) from controls. While most studies have focused on brain connectivity during resting state episodes and regions of interest approaches (ROI), a wealth of task-based fMRI datasets have been acquired in these populations in the last decade. This calls for techniques that can leverage information not only from a single dataset, but from several existing datasets that might share some common features and biomarkers. We propose a fully data-driven (voxel-based) approach that we apply to two different fMRI experiments with social stimuli (faces and bodies). The method, based on Support Vector Machines (SVMs) and Recursive Feature Elimination (RFE), is first trained for each experiment independently and each output is then combined to obtain a final classification output. Second, this RFE output is used to determine which voxels are most often selected for classification to generate maps of significant discriminative activity. Finally, to further explore the clinical validity of the approach, we correlate phenotypic information with obtained classifier scores. The results reveal good classification accuracy (range between 69% and 92.3%). Moreover, we were able to identify discriminative activity patterns pertaining to the social brain without relying on a priori ROI definitions. Finally, social motivation was the only dimension which correlated with classifier scores, suggesting that it is the main dimension captured by the classifiers. Altogether, we believe that the present RFE method proves to be efficient and may help identifying relevant biomarkers by taking advantage of acquired task-based fMRI datasets in psychiatric populations.

  5. Aberrant Oscillatory Activity during Simple Movement in Task-Specific Focal Hand Dystonia

    PubMed Central

    Hinkley, Leighton B. N.; Dolberg, Rebecca; Honma, Susanne; Findlay, Anne; Byl, Nancy N.; Nagarajan, Srikantan S.

    2012-01-01

    In task-specific focal hand dystonia (tspFHD), the temporal dynamics of cortical activity in the motor system and how these processes are related to impairments in sensory and motor function are poorly understood. Here, we use time-frequency reconstructions of magnetoencephalographic (MEG) data to elaborate the temporal and spatial characteristics of cortical activity during movement. A self-paced finger tapping task during MEG recording was performed by 11 patients with tspFHD and 11 matched healthy controls. In both groups robust changes in beta (12–30 Hz) and high gamma (65–90 Hz) oscillatory activity were identified over sensory and motor cortices during button press. A significant decrease [p < 0.05, 1% False Discovery Rate (FDR) corrected] in high gamma power during movements of the affected hand was identified over ipsilateral sensorimotor cortex in the period prior to (−575 ms) and following (725 ms) button press. Furthermore, an increase (p < 0.05, 1% FDR corrected) in beta power suppression following movement of the affected hand was identified over visual cortex in patients with tspFHD. For movements of the unaffected hand, a significant (p < 0.05, 1% FDR corrected) increase in beta power suppression was identified over secondary somatosensory cortex (S2) in the period following button press in patients with tspFHD. Oscillatory activity within in the tspFHD group was however not correlated with clinical measures. Understanding these aberrant oscillatory dynamics can provide the groundwork for interventions that focus on modulating the timing of this activity. PMID:23226140

  6. Working memory activation of neural networks in the elderly as a function of information processing phase and task complexity.

    PubMed

    Charroud, Céline; Steffener, Jason; Le Bars, Emmanuelle; Deverdun, Jérémy; Bonafe, Alain; Abdennour, Meriem; Portet, Florence; Molino, François; Stern, Yaakov; Ritchie, Karen; Menjot de Champfleur, Nicolas; Akbaraly, Tasnime N

    2015-11-01

    Changes in working memory are sensitive indicators of both normal and pathological brain aging and associated disability. The present study aims to further understanding of working memory in normal aging using a large cohort of healthy elderly in order to examine three separate phases of information processing in relation to changes in task load activation. Using covariance analysis, increasing and decreasing neural activation was observed on fMRI in response to a delayed item recognition task in 337 cognitively healthy elderly persons as part of the CRESCENDO (Cognitive REServe and Clinical ENDOphenotypes) study. During three phases of the task (stimulation, retention, probe), increased activation was observed with increasing task load in bilateral regions of the prefrontal cortex, parietal lobule, cingulate gyrus, insula and in deep gray matter nuclei, suggesting an involvement of central executive and salience networks. Decreased activation associated with increasing task load was observed during the stimulation phase, in bilateral temporal cortex, parietal lobule, cingulate gyrus and prefrontal cortex. This spatial distribution of decreased activation is suggestive of the default mode network. These findings support the hypothesis of an increased activation in salience and central executive networks and a decreased activation in default mode network concomitant to increasing task load.

  7. Working memory activation of neural networks in the elderly as a function of information processing phase and task complexity.

    PubMed

    Charroud, Céline; Steffener, Jason; Le Bars, Emmanuelle; Deverdun, Jérémy; Bonafe, Alain; Abdennour, Meriem; Portet, Florence; Molino, François; Stern, Yaakov; Ritchie, Karen; Menjot de Champfleur, Nicolas; Akbaraly, Tasnime N

    2015-11-01

    Changes in working memory are sensitive indicators of both normal and pathological brain aging and associated disability. The present study aims to further understanding of working memory in normal aging using a large cohort of healthy elderly in order to examine three separate phases of information processing in relation to changes in task load activation. Using covariance analysis, increasing and decreasing neural activation was observed on fMRI in response to a delayed item recognition task in 337 cognitively healthy elderly persons as part of the CRESCENDO (Cognitive REServe and Clinical ENDOphenotypes) study. During three phases of the task (stimulation, retention, probe), increased activation was observed with increasing task load in bilateral regions of the prefrontal cortex, parietal lobule, cingulate gyrus, insula and in deep gray matter nuclei, suggesting an involvement of central executive and salience networks. Decreased activation associated with increasing task load was observed during the stimulation phase, in bilateral temporal cortex, parietal lobule, cingulate gyrus and prefrontal cortex. This spatial distribution of decreased activation is suggestive of the default mode network. These findings support the hypothesis of an increased activation in salience and central executive networks and a decreased activation in default mode network concomitant to increasing task load. PMID:26456114

  8. Muscular forearm activation in hand-grip tasks with superimposition of mechanical vibrations.

    PubMed

    Fattorini, L; Tirabasso, A; Lunghi, A; Di Giovanni, R; Sacco, F; Marchetti, E

    2016-02-01

    The purpose of this paper is to evaluate the muscular activation of the forearm, with or without vibration stimuli at different frequencies while performing a grip tasks of 45s at various level of exerted force. In 16 individuals, 9 females and 7 males, the surface electromyogram (EMG) of extensor carpi radialis longus and the flexor carpi ulnari muscles were assessed. At a short latency from onset EMG, RMS and the level of MU synchronization were assessed to evaluate the muscular adaptations. Whilst a trend of decay of EMG Median frequency (MDFd) was employed as an index of muscular fatigue. Muscular tasks consists of the grip of an instrumented handle at a force level of 20%, 30%, 40%, 60% of the maximum voluntary force. Vibration was supplied by a shaker to the hand in mono-frequential waves at 20, 30, 33 and 40Hz. In relation to EMG, RMS and MU synchronization, the muscular activation does not seem to change with the superimposition of the mechanical vibrations, on the contrary a lower MDFd was observed at 33Hz than in absence of vibration. This suggests an early muscular fatigue induced by vibration due to the fact that 33Hz is a resonance frequency for the hand-arm system.

  9. Brain activation during a social attribution task in adolescents with moderate to severe traumatic brain injury.

    PubMed

    Scheibel, Randall S; Newsome, Mary R; Wilde, Elisabeth A; McClelland, Michelle M; Hanten, Gerri; Krawczyk, Daniel C; Cook, Lori G; Chu, Zili D; Vásquez, Ana C; Yallampalli, Ragini; Lin, Xiaodi; Hunter, Jill V; Levin, Harvey S

    2011-01-01

    The ability to make accurate judgments about the mental states of others, sometimes referred to as theory of mind (ToM), is often impaired following traumatic brain injury (TBI), and this deficit may contribute to problems with interpersonal relationships. The present study used an animated social attribution task (SAT) with functional magnetic resonance imaging (fMRI) to examine structures mediating ToM in adolescents with moderate to severe TBI. The study design also included a comparison group of matched, typically developing (TD) adolescents. The TD group exhibited activation within a number of areas that are thought to be relevant to ToM, including the medial prefrontal and anterior cingulate cortex, fusiform gyrus, and posterior temporal and parietal areas. The TBI subjects had significant activation within many of these same areas, but their activation was generally more intense and excluded the medial prefrontal cortex. Exploratory regression analyses indicated a negative relation between ToM-related activation and measures of white matter integrity derived from diffusion tensor imaging, while there was also a positive relation between activation and lesion volume. These findings are consistent with alterations in the level and pattern of brain activation that may be due to the combined influence of diffuse axonal injury and focal lesions.

  10. Watching TV news as a memory task -- brain activation and age effects

    PubMed Central

    2010-01-01

    Background Neuroimaging studies which investigate brain activity underlying declarative memory processes typically use artificial, unimodal laboratory stimuli. In contrast, we developed a paradigm which much more closely approximates real-life situations of information encoding. Methods In this study, we tested whether ecologically valid stimuli - clips of a TV news show - are apt to assess memory-related fMRI activation in healthy participants across a wide age range (22-70 years). We contrasted brain responses during natural stimulation (TV news video clips) with a control condition (scrambled versions of the same clips with reversed audio tracks). After scanning, free recall performance was assessed. Results The memory task evoked robust activation of a left-lateralized network, including primarily lateral temporal cortex, frontal cortex, as well as the left hippocampus. Further analyses revealed that - when controlling for performance effects - older age was associated with greater activation of left temporal and right frontal cortex. Conclusion We demonstrate the feasibility of assessing brain activity underlying declarative memory using a natural stimulation paradigm with high ecological validity. The preliminary result of greater brain activation with increasing age might reflect an attempt to compensate for decreasing episodic memory capacity associated with aging. PMID:20738888

  11. Rhythmic Components in Extracranial Brain Signals Reveal Multifaceted Task Modulation of Overlapping Neuronal Activity

    PubMed Central

    van Ede, Freek; Maris, Eric

    2016-01-01

    Oscillatory neuronal activity is implicated in many cognitive functions, and its phase coupling between sensors may reflect networks of communicating neuronal populations. Oscillatory activity is often studied using extracranial recordings and compared between experimental conditions. This is challenging, because there is overlap between sensor-level activity generated by different sources, and this can obscure differential experimental modulations of these sources. Additionally, in extracranial data, sensor-level phase coupling not only reflects communicating populations, but can also be generated by a current dipole, whose sensor-level phase coupling does not reflect source-level interactions. We present a novel method, which is capable of separating and characterizing sources on the basis of their phase coupling patterns as a function of space, frequency and time (trials). Importantly, this method depends on a plausible model of a neurobiological rhythm. We present this model and an accompanying analysis pipeline. Next, we demonstrate our approach, using magnetoencephalographic (MEG) recordings during a cued tactile detection task as a case study. We show that the extracted components have overlapping spatial maps and frequency content, which are difficult to resolve using conventional pairwise measures. Because our decomposition also provides trial loadings, components can be readily contrasted between experimental conditions. Strikingly, we observed heterogeneity in alpha and beta sources with respect to whether their activity was suppressed or enhanced as a function of attention and performance, and this happened both in task relevant and irrelevant regions. This heterogeneity contrasts with the common view that alpha and beta amplitude over sensory areas are always negatively related to attention and performance. PMID:27336159

  12. Abnormal functional activation during a simple word repetition task: A PET study of adult dyslexics.

    PubMed

    McCrory, E; Frith, U; Brunswick, N; Price, C

    2000-09-01

    Eight dyslexic subjects, impaired on a range of tasks requiring phonological processing, were matched for age and general ability with six control subjects. Participants were scanned using positron emission tomography (PET) during three conditions: repeating real words, repeating pseudowords, and rest. In both groups, speech repetition relative to rest elicited widespread bilateral activation in areas associated with auditory processing of speech; there were no significant differences between words and pseudowords. However, irrespective of word type, the dyslexic group showed less activation than the control group in the right superior temporal and right post-central gyri and also in the left cerebellum. Notably, the right anterior superior temporal cortex (Brodmann's area 22 [BA 22]) was less activated in each of the eight dyslexic subjects, compared to each of the six control subjects. This deficit appears to be specific to auditory repetition as it was not detected in a previous study of reading which used the same sets of stimuli (Brunswick, N., McCrory, E., Price, C., Frith, C.D., & Frith, U. [1999]. Explicit and implicit processing of words and pseudowords by adult developmental dyslexics: A search for Wernicke's Wortschatz? Brain, 122, 1901-1917). This implies that the observed neural manifestation of developmental dyslexia is task-specific (i.e., functional rather than structural). Other studies of normal subjects indicate that attending to the phonetic structure of speech leads to a decrease in right-hemisphere processing. Lower right hemisphere activation in the dyslexic group may therefore indicate less processing of non-phonetic aspects of speech, allowing greater salience to be accorded to phonological aspects of attended speech. PMID:11054918

  13. Center for Radiation Research. 1990 technical activities

    SciTech Connect

    Kuyatt, C.E.

    1991-02-01

    The report summarizes research projects, measurement method development, calibration and testing and data evaluation activities that were carried out during Fiscal Year 1990 in the NIST Center for Radiation Research. These activities fall in the areas of radiometric physics, radiation sources and instrumentation, and ionizing radiation.

  14. Exploratory Research on Novel Coal Liquefaction Concept - Task 2: Evaluation of Process Steps.

    SciTech Connect

    Brandes, S.D.; Winschel, R.A.

    1997-05-01

    A novel direct coal liquefaction technology is being investigated in a program being conducted by CONSOL Inc. with the University of Kentucky, Center for Applied Energy Research and LDP Associates under DOE Contract DE-AC22-95PC95050. The novel concept consists of a new approach to coal liquefaction chemistry which avoids some of the inherent limitations of current high-temperature thermal liquefaction processes. The chemistry employed is based on hydride ion donation to solubilize coal at temperatures (350-400{degrees}C) significantly lower than those typically used in conventional coal liquefaction. The process concept being explored consists of two reaction stages. In the first stage, the coal is solubilized by hydride ion donation. In the second, the products are catalytically upgraded to acceptable refinery feedstocks. The program explores not only the initial solubilization step, but integration of the subsequent processing steps, including an interstage solids-separation step, to produce distillate products. A unique feature of the process concept is that many of the individual reaction steps can be decoupled, because little recycle around the liquefaction system is expected. This allows for considerable latitude in the process design. Furthermore, this has allowed for each key element in the process to be explored independently in laboratory work conducted under Task 2 of the program.

  15. Energy and environmental research emphasizing low-rank coal: Task 7.2, Resource data evaluation. Topical report, July 1994--May 1995

    SciTech Connect

    Hartman, J.H.

    1995-06-01

    The Resource Data Evaluation subtask of the US Department of Energy (DOE) base program represents an Energy & Environmental Research Center (EERC) initiative to promote the integration of geographic information system (GIS) technologies with other ongoing and planned EERC research in the areas of resource utilization, remediation, land use planning, and regulatory and policy assessment. Significant demand for GIS-based information already exists for energy resource evaluation, interpretation of remote sensing data, environmental assessment at the state and local levels, and use in strategic planning. The objective of this task was to determine the appropriate platform and approach upon which to develop GIS applications for optimizing resource evaluation and integrating this information with related areas of interest. Activities associated with Task 7.2, Resource Data Evaluation, were conducted primarily during the first half of the project year. These activities included tasks associated with the development and implementation of GIS databases and construction of digitized files for research pertaining to energy studies. As previously noted, database design was undertaken for two EERC projects: 1) coal occurrence in Bowman and adjacent counties in the Fort Union Coal Region of southwestern North Dakota and 2) energy resource utilization concerns for selected sites in Alaska.

  16. Development of Job Task Inventories and Their Use in Job Analysis Research.

    ERIC Educational Resources Information Center

    Gael, Sidney

    An approach to developing job task inventory questionnaires by interviewing supervisors or job incumbents is described. An initial interview provides the bulk of the information from which task statements will be extracted. A verification interview is conducted with a different interviewee to check and modify information obtained in the initial…

  17. Automated Trait Scores for "TOEFL"® Writing Tasks. Research Report. ETS RR-15-14

    ERIC Educational Resources Information Center

    Attali, Yigal; Sinharay, Sandip

    2015-01-01

    The "e-rater"® automated essay scoring system is used operationally in the scoring of "TOEFL iBT"® independent and integrated tasks. In this study we explored the psychometric added value of reporting four trait scores for each of these two tasks, beyond the total e-rater score.The four trait scores are word choice, grammatical…

  18. Tasks Essential to Successful Performance as a Tobacco Producer. Summary of Research.

    ERIC Educational Resources Information Center

    Carter, David M.; And Others

    The major purpose of the occupational survey was to identify the skills which are performed and essential for success for a tobacco producer. The specific objectives of this survey were: (1) develop and validate an initial task inventory for the tobacco producer, (2) identify the specific tasks performed by the tobacco producer, and (3) determine…

  19. Researching Pedagogic Tasks: Second Language Learning, Teaching, and Testing. Applied Linguistics and Language Study.

    ERIC Educational Resources Information Center

    Bygate, Martin; Skehan, Peter; Swain, Merrill

    This book brings together a series of empirical studies into the use of pedagogical tasks for second language learning, with a view to better understanding the structure of tasks, their impact on students, and their use by teachers. This edited volume starts with an introduction to the background and key issues in the topic area. Each section…

  20. CSS Council Task Force on Reauthorization: Recommendations for Improving Federal Aid Delivery. Research Report.

    ERIC Educational Resources Information Center

    College Entrance Examination Board, New York, NY.

    The College Scholarship Service (CSS) Council Task Force on Reauthorization presented its recommendations to the CSS Council in December 2002. The Task Force focused its recommendations on issues that address the overarching goal of ensuring access to higher education for the most needy students. The recommendations reflect the consensus of CSS…

  1. 42 CFR 2.52 - Research activities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Research activities. 2.52 Section 2.52 Public... OF ALCOHOL AND DRUG ABUSE PATIENT RECORDS Disclosures Without Patient Consent § 2.52 Research... research if the program director makes a determination that the recipient of the patient...

  2. 38 CFR 1.488 - Research activities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... disclosed for the purpose of conducting scientific research. (a) Information in individually identifiable... conducting scientific research if the Under Secretary for Health or designee makes a determination that the... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Research activities....

  3. Embedding Research Activities to Enhance Student Learning

    ERIC Educational Resources Information Center

    Webster, Cynthia M.; Kenney, Jacqueline

    2011-01-01

    Purpose: The purpose of this paper's novel, research-oriented approach is to embed research-based activities in a core second-year course of a university business degree program to support and develop student research capabilities. Design/methodology/approach: The design draws on Boud and Prosser's work to foster participation in a…

  4. [Climate chance and research activity].

    PubMed

    Manuel, Celie

    2009-10-26

    There are three main focus areas relevant to health in research related to climate change: 1) disentangling of the complex associations between climate-sensitive risk factors and health 2) guidance as to where, when and how effective health adaptation strategies may be implemented for maximum effect, and 3) health impact assessment (with a focus on health co-benefits) of climate-related policies in other sectors. Further development in each of these areas will provide important opportunities for strengthening health promotion and protection.

  5. An Integrated Extravehicular Activity Research Plan

    NASA Technical Reports Server (NTRS)

    Abercromby, Andrew F. J.; Ross, Amy J.; Cupples, J. Scott

    2016-01-01

    Multiple organizations within NASA and outside of NASA fund and participate in research related to extravehicular activity (EVA). In October 2015, representatives of the EVA Office, the Crew and Thermal Systems Division (CTSD), and the Human Research Program (HRP) at NASA Johnson Space Center agreed on a formal framework to improve multi-year coordination and collaboration in EVA research. At the core of the framework is an Integrated EVA Research Plan and a process by which it will be annually reviewed and updated. The over-arching objective of the collaborative framework is to conduct multi-disciplinary cost-effective research that will enable humans to perform EVAs safely, effectively, comfortably, and efficiently, as needed to enable and enhance human space exploration missions. Research activities must be defined, prioritized, planned and executed to comprehensively address the right questions, avoid duplication, leverage other complementary activities where possible, and ultimately provide actionable evidence-based results in time to inform subsequent tests, developments and/or research activities. Representation of all appropriate stakeholders in the definition, prioritization, planning and execution of research activities is essential to accomplishing the over-arching objective. A formal review of the Integrated EVA Research Plan will be conducted annually. External peer review of all HRP EVA research activities including compilation and review of published literature in the EVA Evidence Book is already performed annually. Coordination with stakeholders outside of the EVA Office, CTSD, and HRP is already in effect on a study-by-study basis; closer coordination on multi-year planning with other EVA stakeholders including academia is being actively pursued. Details of the current Integrated EVA Research Plan are presented including description of ongoing and planned research activities in the areas of: Benchmarking; Anthropometry and Suit Fit; Sensors; Human

  6. Higher Media Multi-Tasking Activity Is Associated with Smaller Gray-Matter Density in the Anterior Cingulate Cortex

    PubMed Central

    Loh, Kep Kee; Kanai, Ryota

    2014-01-01

    Media multitasking, or the concurrent consumption of multiple media forms, is increasingly prevalent in today’s society and has been associated with negative psychosocial and cognitive impacts. Individuals who engage in heavier media-multitasking are found to perform worse on cognitive control tasks and exhibit more socio-emotional difficulties. However, the neural processes associated with media multi-tasking remain unexplored. The present study investigated relationships between media multitasking activity and brain structure. Research has demonstrated that brain structure can be altered upon prolonged exposure to novel environments and experience. Thus, we expected differential engagements in media multitasking to correlate with brain structure variability. This was confirmed via Voxel-Based Morphometry (VBM) analyses: Individuals with higher Media Multitasking Index (MMI) scores had smaller gray matter density in the anterior cingulate cortex (ACC). Functional connectivity between this ACC region and the precuneus was negatively associated with MMI. Our findings suggest a possible structural correlate for the observed decreased cognitive control performance and socio-emotional regulation in heavy media-multitaskers. While the cross-sectional nature of our study does not allow us to specify the direction of causality, our results brought to light novel associations between individual media multitasking behaviors and ACC structure differences. PMID:25250778

  7. Higher media multi-tasking activity is associated with smaller gray-matter density in the anterior cingulate cortex.

    PubMed

    Loh, Kep Kee; Kanai, Ryota

    2014-01-01

    Media multitasking, or the concurrent consumption of multiple media forms, is increasingly prevalent in today's society and has been associated with negative psychosocial and cognitive impacts. Individuals who engage in heavier media-multitasking are found to perform worse on cognitive control tasks and exhibit more socio-emotional difficulties. However, the neural processes associated with media multi-tasking remain unexplored. The present study investigated relationships between media multitasking activity and brain structure. Research has demonstrated that brain structure can be altered upon prolonged exposure to novel environments and experience. Thus, we expected differential engagements in media multitasking to correlate with brain structure variability. This was confirmed via Voxel-Based Morphometry (VBM) analyses: Individuals with higher Media Multitasking Index (MMI) scores had smaller gray matter density in the anterior cingulate cortex (ACC). Functional connectivity between this ACC region and the precuneus was negatively associated with MMI. Our findings suggest a possible structural correlate for the observed decreased cognitive control performance and socio-emotional regulation in heavy media-multitaskers. While the cross-sectional nature of our study does not allow us to specify the direction of causality, our results brought to light novel associations between individual media multitasking behaviors and ACC structure differences.

  8. Metabolic equivalents of task are confounded by adiposity, which disturbs objective measurement of physical activity.

    PubMed

    Tompuri, Tuomo T

    2015-01-01

    Physical activity refers any bodily movements produced by skeletal muscles that expends energy. Hence the amount and the intensity of physical activity can be assessed by energy expenditure. Metabolic equivalents of task (MET) are multiplies of the resting metabolism reflecting metabolic rate during exercise. The standard MET is defined as 3.5 ml/min/kg. However, the expression of energy expenditure by body weight to normalize the size differences between subjects causes analytical hazards: scaling by body weight does not have a physiological, mathematical, or physical rationale. This review demonstrates by examples that false methodology may cause paradoxical observations if physical activity would be assessed by body weight scaled values such as standard METs. While standard METs are confounded by adiposity, lean mass proportional measures of energy expenditure would enable a more truthful choice to assess physical activity. While physical activity as a behavior and cardiorespiratory fitness or adiposity as a state represents major determinants of public health, specific measurements of health determinants must be understood to enable a truthful evaluation of the interactions and their independent role as a health predictor.

  9. Metabolic equivalents of task are confounded by adiposity, which disturbs objective measurement of physical activity

    PubMed Central

    Tompuri, Tuomo T.

    2015-01-01

    Physical activity refers any bodily movements produced by skeletal muscles that expends energy. Hence the amount and the intensity of physical activity can be assessed by energy expenditure. Metabolic equivalents of task (MET) are multiplies of the resting metabolism reflecting metabolic rate during exercise. The standard MET is defined as 3.5 ml/min/kg. However, the expression of energy expenditure by body weight to normalize the size differences between subjects causes analytical hazards: scaling by body weight does not have a physiological, mathematical, or physical rationale. This review demonstrates by examples that false methodology may cause paradoxical observations if physical activity would be assessed by body weight scaled values such as standard METs. While standard METs are confounded by adiposity, lean mass proportional measures of energy expenditure would enable a more truthful choice to assess physical activity. While physical activity as a behavior and cardiorespiratory fitness or adiposity as a state represents major determinants of public health, specific measurements of health determinants must be understood to enable a truthful evaluation of the interactions and their independent role as a health predictor. PMID:26321958

  10. Mental addition in bilinguals: an FMRI study of task-related and performance-related activation.

    PubMed

    Lin, Jo-Fu Lotus; Imada, Toshiaki; Kuhl, Patricia K

    2012-08-01

    Behavioral studies show that bilinguals are slower and less accurate when performing mental calculation in their nondominant (second; L2) language than in their dominant (first; L1) language. However, little is known about the neural correlates associated with the performance differences observed between bilinguals' 2 languages during arithmetic processing. To address the cortical activation differences between languages, the current study examined task-related and performance-related brain activation during mental addition when problems were presented auditorily in participants' L1 and L2. Eleven Chinese-English bilinguals heard 2-digit addition problems that required exact or approximate calculations. Functional magnetic resonance imaging results showed that auditorily presented multidigit addition in bilinguals activates bilateral inferior parietal and inferior frontal regions in both L1 and L2. Language differences were observed in the form of greater activation for L2 exact addition in the left inferior frontal area. A negative correlation between brain activation and behavioral performance during mental addition in L2 was observed in the left inferior parietal area. Current results provide further evidence for the effects of language-specific experience on arithmetic processing in bilinguals at the cortical level.

  11. The influence of motor expertise on the brain activity of motor task performance: A meta-analysis of functional magnetic resonance imaging studies.

    PubMed

    Yang, Jie

    2015-06-01

    Previous research has investigated the influence of long-term motor training on the brain activity of motor processes, but the findings are inconsistent. To clarify how acquiring motor expertise induces cortical reorganization during motor task performance, the current study conducted a quantitative meta-analysis on 26 functional magnetic resonance imaging (fMRI) studies that investigate motor task performance in people with long-term motor training experience (e.g., athletes, musicians, and dancers) and control participants. Meta-analysis of the brain activation in motor experts and novices showed similar effects in the bilateral frontal and parietal regions. The meta-analysis on the contrast between motor experts and novices indicated that experts showed stronger effects in the left inferior parietal lobule (BA 40) than did novices in motor execution and prediction tasks. In motor observation tasks, experts showed stronger effects in the left inferior frontal gyrus (BA 9) and left precentral gyrus (BA 6) than novices. On the contrary, novices had stronger effects in the right motor areas and basal ganglia as compared with motor experts. These results indicate that motor experts have effect increases in brain areas involved in action planning and action comprehension, and suggest that intensive motor training might elaborate the motor representation related to the task performance.

  12. Prefrontal cortex activity during motor tasks with additional mental load requiring attentional demand: a near-infrared spectroscopy study.

    PubMed

    Mandrick, Kevin; Derosiere, Gérard; Dray, Gérard; Coulon, Denis; Micallef, Jean-Paul; Perrey, Stéphane

    2013-07-01

    Functional near-infrared spectroscopy (fNIRS) is suitable for investigating cerebral oxygenation changes during motor and/or mental tasks. In the present study, we investigated how an additional mental load during a motor task at two submaximal loadings affects the fNIRS-measured brain activation over the right prefrontal cortex (PFC). Fifteen healthy males performed isometric grasping contractions at 15% and 30% of the maximal voluntary contraction (MVC) with or without an additional mental (i.e., arithmetic) task. Mental performance, force variability, fNIRS and subjective perception responses were measured in each condition. The performance of the mental task decreased significantly while the force variability increased significantly at 30% MVC as compared to 15% MVC, suggesting that performance of dual-task required more attentional resources. PFC activity increased significantly as the effort increased from 15% to 30% MVC (p<.001). Although a larger change in the deoxyhemoglobin was observed in dual-task conditions (p=.051), PFC activity did not change significantly as compared to the motor tasks alone. In summary, participants were unable to invest more attention and effort in performing the more difficult levels in order to maintain adequate mental performance.

  13. Prefrontal cortex activity during motor tasks with additional mental load requiring attentional demand: a near-infrared spectroscopy study.

    PubMed

    Mandrick, Kevin; Derosiere, Gérard; Dray, Gérard; Coulon, Denis; Micallef, Jean-Paul; Perrey, Stéphane

    2013-07-01

    Functional near-infrared spectroscopy (fNIRS) is suitable for investigating cerebral oxygenation changes during motor and/or mental tasks. In the present study, we investigated how an additional mental load during a motor task at two submaximal loadings affects the fNIRS-measured brain activation over the right prefrontal cortex (PFC). Fifteen healthy males performed isometric grasping contractions at 15% and 30% of the maximal voluntary contraction (MVC) with or without an additional mental (i.e., arithmetic) task. Mental performance, force variability, fNIRS and subjective perception responses were measured in each condition. The performance of the mental task decreased significantly while the force variability increased significantly at 30% MVC as compared to 15% MVC, suggesting that performance of dual-task required more attentional resources. PFC activity increased significantly as the effort increased from 15% to 30% MVC (p<.001). Although a larger change in the deoxyhemoglobin was observed in dual-task conditions (p=.051), PFC activity did not change significantly as compared to the motor tasks alone. In summary, participants were unable to invest more attention and effort in performing the more difficult levels in order to maintain adequate mental performance. PMID:23665138

  14. Global thunderstorm activity research survey

    NASA Technical Reports Server (NTRS)

    Coroniti, S. C.

    1982-01-01

    The published literature on the subject of the monitoring of global thunderstorm activity by instrumented satellites was reviewed. A survey of the properties of selected physical parameters of the thunderstorm is presented. The concepts used by satellites to identify and to measure terrestrial lightning pulses are described. The experimental data acquired by satellites are discussed. The scientific achievements of the satellites are evaluated against the needs of scientists and the potential requirements of user agencies. The performances of the satellites are rated according to their scientific and operational achievements.

  15. Adolescents’ fMRI Activation to a Response Inhibition Task Predicts Future Substance Use

    PubMed Central

    Mahmood, O.M.; Goldenberg, D.; Thayer, R.; Migliorini, R.; Simmons, A.N.; Tapert, S.F.

    2012-01-01

    Background Deficient behavioral regulation may be a risk factor for substance use disorders in adolescents. Abnormalities in brain regions critical to cognitive control have been linked to more intense and problematic future substance use (e.g., (Durazzo, Gazdzinski, Mon, & Meyerhoff, 2010; Falk, Berkman, Whalen, & Lieberman, 2011; Paulus, Tapert, & Schuckit, 2005). The goal of this study was to examine the degree to which brain response to an inhibition task measured in mid-adolescence can predict substance use 18 months later. Method Adolescents aged 16–19 (N=80) performed a go/no-go response inhibition task during fMRI at project baseline, and were followed 18 months later with a detailed interview on substance use and dependence symptoms. Participants were 39 high frequency users and 41 demographically similar low frequency users (458 versus 2 average lifetime drug use occasions at baseline, respectively). Results Across all subjects, no-go trials produced significant increases in neural response in the ventromedial prefrontal cortex and a region including the left angular and supramarginal gyri (p(FWE)<.01, cluster threshold ≥30 voxels). Less ventromedial prefrontal activation but more left angular gyrus activation predicted higher levels of substance use and dependence symptoms in the following 18 months, particularly for those who were high frequency users in mid-adolescence (p<.05). Conclusions These findings are consistent with studies showing that impairments in cognitive control have strong associations with substance use. We found a predictive relationship between atypical activation patterns at baseline and substance use behavior 18 months later, particularly among adolescents with histories of previous heavy use. PMID:23006248

  16. The visual perception of natural motion: abnormal task-related neural activity in DYT1 dystonia.

    PubMed

    Sako, Wataru; Fujita, Koji; Vo, An; Rucker, Janet C; Rizzo, John-Ross; Niethammer, Martin; Carbon, Maren; Bressman, Susan B; Uluğ, Aziz M; Eidelberg, David

    2015-12-01

    Although primary dystonia is defined by its characteristic motor manifestations, non-motor signs and symptoms have increasingly been recognized in this disorder. Recent neuroimaging studies have related the motor features of primary dystonia to connectivity changes in cerebello-thalamo-cortical pathways. It is not known, however, whether the non-motor manifestations of the disorder are associated with similar circuit abnormalities. To explore this possibility, we used functional magnetic resonance imaging to study primary dystonia and healthy volunteer subjects while they performed a motion perception task in which elliptical target trajectories were visually tracked on a computer screen. Prior functional magnetic resonance imaging studies of healthy subjects performing this task have revealed selective activation of motor regions during the perception of 'natural' versus 'unnatural' motion (defined respectively as trajectories with kinematic properties that either comply with or violate the two-thirds power law of motion). Several regions with significant connectivity changes in primary dystonia were situated in proximity to normal motion perception pathways, suggesting that abnormalities of these circuits may also be present in this disorder. To determine whether activation responses to natural versus unnatural motion in primary dystonia differ from normal, we used functional magnetic resonance imaging to study 10 DYT1 dystonia and 10 healthy control subjects at rest and during the perception of 'natural' and 'unnatural' motion. Both groups exhibited significant activation changes across perceptual conditions in the cerebellum, pons, and subthalamic nucleus. The two groups differed, however, in their responses to 'natural' versus 'unnatural' motion in these regions. In healthy subjects, regional activation was greater during the perception of natural (versus unnatural) motion (P < 0.05). By contrast, in DYT1 dystonia subjects, activation was relatively greater

  17. Reduced prefrontal cortex activation in the color-word Stroop task for Chinese dyslexic children: a near-infrared spectroscopy study

    NASA Astrophysics Data System (ADS)

    Sun, Jinyan; Zhai, Jiahuan; Song, Ranran; Zou, Li; Gong, Hui

    2011-01-01

    Behavioral studies have investigated the performance of children with developmental dyslexia in conflict resolution, a function connected with the prefrontal cortex (PFC) closely. However, little is known about the prefrontal activation in conflict resolution for dyslexic children. In the present study, the involvement of the PFC in resolving conflict was evaluated for Chinese dyslexic children by means of near-infrared spectroscopy (NIRS). The NIRS instrument is a portable, continuous-wave system and can measure concentration changes of hemodynamic parameters (including oxy-, deoxy-, and total hemoglobin). Considering better sensitivity, the oxy-hemoglobin (oxy-Hb) was chosen to indicate the prefrontal activation. Ten dyslexic children and 11 normal children were recruited to perform the Chinese-character color-word Stroop task, which included the neutral and color (incongruent) tasks. In behavioral performance, both groups showed significant Stroop effect, longer response time or higher error rate for the color task. In particular, the Stroop interference effect was marginally larger for dyslexic children than normal children in response time. What's more, the two groups showed distinct pattern of oxy-Hb activation during the Stroop tasks. The normal group recruited the bilateral PFC to perform the tasks, while the dyslexic group couldn't activate the bilateral PFC in the difficult color task. Moreover, significantly less color Stroop effect was found in the left PFC for the dyslexic group, showing their disability in coping with the Stroop interference. These findings suggest that the PFC is dysfunctional in conflict resolution for Chinese dyslexic children and that NIRS can be an effective tool in neurological research and clinical application.

  18. Observations of Children’s Interactions with Teachers, Peers, and Tasks across Preschool Classroom Activity Settings

    PubMed Central

    Booren, Leslie M.; Downer, Jason T.; Vitiello, Virginia E.

    2014-01-01

    This descriptive study examined classroom activity settings in relation to children’s observed behavior during classroom interactions, child gender, and basic teacher behavior within the preschool classroom. 145 children were observed for an average of 80 minutes during 8 occasions across 2 days using the inCLASS, an observational measure that conceptualizes behavior into teacher, peer, task, and conflict interactions. Findings indicated that on average children’s interactions with teachers were higher in teacher-structured settings, such as large group. On average, children’s interactions with peers and tasks were more positive in child-directed settings, such as free choice. Children experienced more conflict during recess and routines/transitions. Finally, gender differences were observed within small group and meals. The implications of these findings might encourage teachers to be thoughtful and intentional about what types of support and resources are provided so children can successfully navigate the demands of particular settings. These findings are not meant to discourage certain teacher behaviors or imply value of certain classroom settings; instead, by providing an evidenced-based picture of the conditions under which children display the most positive interactions, teachers can be more aware of choices within these settings and have a powerful way to assist in professional development and interventions. PMID:25717282

  19. Effects of mirror therapy combined with motor tasks on upper extremity function and activities daily living of stroke patients

    PubMed Central

    Kim, Kyunghoon; Lee, Sukmin; Kim, Donghoon; Lee, Kyoungbo; Kim, Youlim

    2016-01-01

    [Purpose] The objective of this study was to investigate the effects of mirror therapy combined with exercise tasks on the function of the upper limbs and activities of daily living. [Subjects and Methods] Twenty-five stroke patients who were receiving physical therapy at K Hospital in Gyeonggi-do, South Korea, were classified into a mirror therapy group (n=12) and a conventional therapy group (n=13). The therapies were applied for 30 minutes per day, five times per week, for a total of four weeks. Upper limb function was measured with the Action Research Arm test, the Fugl-Meyer Assessment, and the Box and Block test, and activities of daily living were measured with the Functional Independence Measure. A paired test was performed to compare the intragroup differences between before training and after four weeks of therapy, and an independent t-test was performed to compare the differences between the two groups before and after four weeks of therapy. [Results] In the intragroup comparison, both groups showed significant differences between measurements taken before and after four weeks of therapy. In the intergroup comparison, the mirror therapy group showed significant improvements compared with the conventional therapy group, both in upper limb function and activities of daily living. [Conclusion] The findings of this study demonstrated that mirror therapy is more effective than conventional therapy for the training of stroke patients to improve their upper limb function and activities of daily living. PMID:27065534

  20. Personality effects on cardiovascular reactivity: need for closure moderates the impact of task difficulty on engagement-related myocardial beta-adrenergic activity.

    PubMed

    Richter, Michael; Baeriswyl, Eric; Roets, Arne

    2012-05-01

    An experiment assessed the joint effect of dispositional need for closure (NFC) and task difficulty on engagement-related myocardial beta-adrenergic activity. Participants who scored either low or high on the NFC scale performed an ambiguous categorization task with either low or high difficulty. Confirming the theory-derived predictions, task difficulty effects on pre-ejection period (PEP) reactivity were moderated by NFC. If difficulty was low, PEP reactivity was low and independent of the participants' NFC level. If difficulty was high, participants with high NFC showed increased PEP reactivity compared to participants with low NFC. These results extend previous research on Wright's model of engagement-related cardiovascular reactivity and suggest that the model may provide a useful framework for assessing the impact of personality on cardiovascular response.

  1. Analysis of brain activity and response to colour stimuli during learning tasks: an EEG study

    NASA Astrophysics Data System (ADS)

    Folgieri, Raffaella; Lucchiari, Claudio; Marini, Daniele

    2013-02-01

    The research project intends to demonstrate how EEG detection through BCI device can improve the analysis and the interpretation of colours-driven cognitive processes through the combined approach of cognitive science and information technology methods. To this end, firstly it was decided to design an experiment based on comparing the results of the traditional (qualitative and quantitative) cognitive analysis approach with the EEG signal analysis of the evoked potentials. In our case, the sensorial stimulus is represented by the colours, while the cognitive task consists in remembering the words appearing on the screen, with different combination of foreground (words) and background colours. In this work we analysed data collected from a sample of students involved in a learning process during which they received visual stimuli based on colour variation. The stimuli concerned both the background of the text to learn and the colour of the characters. The experiment indicated some interesting results concerning the use of primary (RGB) and complementary (CMY) colours.

  2. Emotional task management: neural correlates of switching between affective and non-affective task-sets

    PubMed Central

    Reeck, Crystal

    2015-01-01

    Although task-switching has been investigated extensively, its interaction with emotionally salient task content remains unclear. Prioritized processing of affective stimulus content may enhance accessibility of affective task-sets and generate increased interference when switching between affective and non-affective task-sets. Previous research has demonstrated that more dominant task-sets experience greater switch costs, as they necessitate active inhibition during performance of less entrenched tasks. Extending this logic to the affective domain, the present experiment examined (a) whether affective task-sets are more dominant than non-affective ones, and (b) what neural mechanisms regulate affective task-sets, so that weaker, non-affective task-sets can be executed. While undergoing functional magnetic resonance imaging, participants categorized face stimuli according to either their gender (non-affective task) or their emotional expression (affective task). Behavioral results were consistent with the affective task dominance hypothesis: participants were slower to switch to the affective task, and cross-task interference was strongest when participants tried to switch from the affective to the non-affective task. These behavioral costs of controlling the affective task-set were mirrored in the activation of a right-lateralized frontostriatal network previously implicated in task-set updating and response inhibition. Connectivity between amygdala and right ventrolateral prefrontal cortex was especially pronounced during cross-task interference from affective features. PMID:25552571

  3. Activation Theory and Uses and Gratifications Research.

    ERIC Educational Resources Information Center

    Tate, E. D.

    Uses and gratifications research involves a critical appraisal of conceptual and theoretical issues in mass communication and is concerned with what audience members do with the media. Activation theory understands people as active manipulators of their environment. (Activation refers to that level of psychological and physiological excitement an…

  4. An Exploratory Study of Video Browsing User Interface Designs and Research Methodologies: Effectiveness in Information Seeking Tasks.

    ERIC Educational Resources Information Center

    Tse, Tony; Vegh, Sandor; Shneiderman, Ben; Marchionini, Gary

    1999-01-01

    The purpose of this exploratory study was to develop research methods to compare the effectiveness of two video browsing interface designs, or surrogates--one static (storyboard) and one dynamic (slide show)--on two distinct information seeking tasks (gist determination and object recognition). (AEF)

  5. The Effects of Task Instruction Sheets on the Performance of Vocational Horticulture Students. Summary of Research, 29.

    ERIC Educational Resources Information Center

    Scanlon, Dennis C.; Newcomb, L. H.

    A study investigated the effect that task instruction sheets had on the performance of vocational horticulture students when being taught a unit on poinsettia production. Using a post-test only control group design, researchers administered a 35-item multiple choice test on poinsettia production to 207 students in 12 randomly selected eleventh…

  6. Greater Impulsivity is Associated with Decreased Brain Activation in Obese Women during a Delay Discounting Task

    PubMed Central

    Stoeckel, Luke E.; Murdaugh, Donna L.; Cox, James E.; Cook, Edwin W.; Weller, Rosalyn E.

    2012-01-01

    Impulsivity and poor inhibitory control are associated with higher rates of delay discounting (DD) or a greater preference for smaller, more immediate rewards at the expense of larger, but delayed rewards. Of the many functional magnetic resonance imaging (fMRI) studies of DD, few have investigated the correlation between individual differences in DD rate and brain activation related to DD trial difficulty, with difficult DD trials expected to activate putative executive function brain areas involved in impulse control. In the current study, we correlated patterns of brain activation as measured by fMRI during difficult vs. easy trials of a DD task with DD rate (k) in obese women. Difficulty was defined by how much a reward choice deviated from an individual’s ‘indifference point’, or the point where the subjective preference for an immediate and a delayed reward was approximately equivalent. We found that greater delay discounting was correlated with less modulation of activation in putative executive function brain areas, such as the middle and superior frontal gyri and inferior parietal lobule, in response to difficult compared to easy DD trials. These results support the suggestion that increased impulsivity is associated with deficient functioning of executive function areas of the brain. PMID:22948956

  7. Influence of Task Difficulty and Background Music on Working Memory Activity: Developmental Considerations.

    ERIC Educational Resources Information Center

    Kaniel, Shlomo; Aram, Dorit

    1998-01-01

    A study of 300 children in kindergarten, grade 2, and grade 6 found that background music improved visual discrimination task performance at the youngest and middle ages and had no effect on the oldest participants. On a square identification task, background music had no influence on easy and difficult tasks but lowered performance on…

  8. Promoting Physical Activity in Hong Kong Chinese Young People: Factors Influencing Their Subjective Task Values and Expectancy Beliefs in Physical Activity

    ERIC Educational Resources Information Center

    Pang, Bonnie

    2014-01-01

    According to Eccles et al.'s (1983) Expectancy Value Model, the two major constructs that influence young people's activity choice are subjective task value and expectancy beliefs (Eccles et al., 1983). Eccles et al. (1983) conceptually distinguished four dimensions of subjective task value: attainment value, intrinsic value, utility…

  9. Performance of a 6-Degree-of-Freedom Active Microsurgical Manipulator in Handheld Tasks

    PubMed Central

    Yang, Sungwook; Wells, Trent S.; MacLachlan, Robert A.; Riviere, Cameron N.

    2013-01-01

    This paper presents the first experimental results from human users of a new 6-degree-of-freedom handheld micromanipulator. This is the latest prototype of a fully-handheld system, known as “Micron,” which performs active compensation of hand tremor for microsurgery. The manipulator is a miniature Gough-Stewart platform incorporating linear ultrasonic motors that provide a cylindrical workspace 4 mm long and 4 mm wide. In addition, the platform allows the possibility of imposing a remote center of motion for controlling motion not only at the tip but also at the entry point in the sclera of the eye. We demonstrate hand tremor reduction in both static and dynamic micromanipulation tasks on a rubber pad. The handheld performance is also evaluated in an artificial eye model while imposing a remote center of motion. In all cases, hand tremor is significantly reduced. PMID:24111024

  10. Early planning activity in frontal and parietal cortex in a simplified task

    PubMed Central

    Andersen, Richard A.

    2015-01-01

    Cortical planning activity has traditionally been probed with visual targets. However, external sensory signals might obscure early correlates of internally generated plans. We devised a nonspatial decision-making task in which the monkey is encouraged to decide randomly whether to reach or saccade in the absence of sensory stimuli. Neurons in frontal and parietal planning areas (in and around the arcuate and intraparietal sulci) showed responses predictive of the monkey's upcoming movement at early stages during the planning process. Neurons predicted the animal's future movements several seconds beforehand, sometimes before the trial even began. These data cast new light on the role of the cerebral cortex in the action planning process, when the animal is free to decide on his own actions in the absence of extraneous sensory cues. PMID:25761951

  11. Inter-rater reliability of cyclic and non-cyclic task assessment using the hand activity level in appliance manufacturing

    PubMed Central

    Paulsen, Robert; Schwatka, Natalie; Gober, Jennifer; Gilkey, David; Anton, Dan; Gerr, Fred; Rosecrance, John

    2015-01-01

    This study evaluated the inter-rater reliability of the American Conference of Governmental Industrial Hygienists (ACGIH®) hand activity level (HAL), an observational ergonomic assessment method used to estimate physical exposure to repetitive exertions during task performance. Video recordings of 858 cyclic and non-cyclic appliance manufacturing tasks were assessed by sixteen pairs of raters using the HAL visual-analog scale. A weighted Pearson Product Moment-Correlation Coefficient was used to evaluate the agreement between the HAL scores recorded by each rater pair, and the mean weighted correlation coefficients for cyclic and non-cyclic tasks were calculated. Results indicated that the HAL is a reliable exposure assessment method for cyclic (r̄-barw = 0.69) and non-cyclic work tasks (r̄-barw = 0.68). When the two reliability scores were compared using a two-sample Student's t-test, no significant difference in reliability (p = 0.63) between these work task categories was found. This study demonstrated that the HAL may be a useful measure of exposure to repetitive exertions during cyclic and non-cyclic tasks. Relevance to industry Exposure to hazardous levels of repetitive action during non-cyclic task completion has traditionally been difficult to assess using simple observational techniques. The present study suggests that ergonomists could use the HAL to reliably and easily evaluate exposures associated with some non-cyclic work tasks. PMID:26120222

  12. Transmission research activities at NASA Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Lewicki, D. G.

    1990-01-01

    A joint research program, to advance the technology of rotorcraft transmissions, consists of analytical and experimental efforts to achieve the overall goals of reducing transmission weight and noise, while increasing life and reliability. Recent activities in the areas of transmission and related component research are highlighted. Current areas include specific technologies in support of military rotary wing aviation, gearing technology, transmission noise reduction studies, a recent interest in gearbox diagnostics, and advanced transmission system studies. Results of recent activities are presented along with near term research plans.

  13. Antiviral Drug Research Proposal Activity

    PubMed Central

    Injaian, Lisa; Smith, Ann C.; Shipley, Jennifer German; Marbach-Ad, Gili; Fredericksen, Brenda

    2011-01-01

    The development of antiviral drugs provides an excellent example of how basic and clinical research must be used together in order to achieve the final goal of treating disease. A Research Oriented Learning Activity was designed to help students to better understand how basic and clinical research can be combined toward a common goal. Through this project students gained a better understanding of the process of scientific research and increased their information literacy in the field of virology. The students worked as teams to research the many aspects involved in the antiviral drug design process, with each student becoming an “expert” in one aspect of the project. The Antiviral Drug Research Proposal (ADRP) culminated with students presenting their proposals to their peers and local virologists in a poster session. Assessment data showed increased student awareness and knowledge of the research process and the steps involved in the development of antiviral drugs as a result of this activity. PMID:23653735

  14. Ventromedial prefrontal theta activity during rapid eye movement sleep is associated with improved decision-making on the Iowa Gambling Task.

    PubMed

    Seeley, Corrine J; Smith, Carlyle T; MacDonald, Kevin J; Beninger, Richard J

    2016-06-01

    Recent research is beginning to reveal an intricate relationship between sleep and decision-making. The Iowa Gambling Task (IGT) is a unique decision-making task that relies on the ventromedial prefrontal cortex (vmPFC), an area that integrates and weighs previous experiences with reward and loss to select choices with the highest overall value. Recently, it has been demonstrated that a period of sleep can enhance decision-making on this task. Our study investigated the sleep mechanisms (sleep stages and cortical activity) that underlie this improvement. We recorded electrophysiology for 3 consecutive nights: a habituation, baseline, and acquisition night. On acquisition night participants were administered either a 200-trial IGT (IGT group; n = 13) or a 200-trial control (IGT-control group; n = 8) version of the task prior to sleep. Compared with baseline, the IGT group had a significant increase in theta frequency (4 Hz-8 Hz) on cites located above vmPFC and left prefrontal cortex during REM sleep. This increase correlated with subsequent performance improvement from deck B, a high reward deck with negative long-term outcomes. Furthermore, presleep emotional arousal (measured via skin conductance response) toward deck B correlated to increased theta activity above the right vmPFC during REM sleep. Overall, these results suggests that insight into deck B may be enhanced via vmPFC theta activity during REM sleep and REM sleep may have distinct mechanisms for processing decision-making information. (PsycINFO Database Record PMID:26820586

  15. Ventromedial prefrontal theta activity during rapid eye movement sleep is associated with improved decision-making on the Iowa Gambling Task.

    PubMed

    Seeley, Corrine J; Smith, Carlyle T; MacDonald, Kevin J; Beninger, Richard J

    2016-06-01

    Recent research is beginning to reveal an intricate relationship between sleep and decision-making. The Iowa Gambling Task (IGT) is a unique decision-making task that relies on the ventromedial prefrontal cortex (vmPFC), an area that integrates and weighs previous experiences with reward and loss to select choices with the highest overall value. Recently, it has been demonstrated that a period of sleep can enhance decision-making on this task. Our study investigated the sleep mechanisms (sleep stages and cortical activity) that underlie this improvement. We recorded electrophysiology for 3 consecutive nights: a habituation, baseline, and acquisition night. On acquisition night participants were administered either a 200-trial IGT (IGT group; n = 13) or a 200-trial control (IGT-control group; n = 8) version of the task prior to sleep. Compared with baseline, the IGT group had a significant increase in theta frequency (4 Hz-8 Hz) on cites located above vmPFC and left prefrontal cortex during REM sleep. This increase correlated with subsequent performance improvement from deck B, a high reward deck with negative long-term outcomes. Furthermore, presleep emotional arousal (measured via skin conductance response) toward deck B correlated to increased theta activity above the right vmPFC during REM sleep. Overall, these results suggests that insight into deck B may be enhanced via vmPFC theta activity during REM sleep and REM sleep may have distinct mechanisms for processing decision-making information. (PsycINFO Database Record

  16. Amplitude and timing of somatosensory cortex activity in Task Specific Focal Hand Dystonia

    PubMed Central

    Dolberg, Rebecca; Hinkley, Leighton B. N.; Honma, Susanne; Zhu, Zhao; Findlay, Anne M.; Byl, Nancy N.; Nagarjan, Srikantan S.

    2011-01-01

    Objective Task-specific focal hand dystonia (tspFHD) is a movement disorder diagnosed in individuals performing repetitive hand behaviors. The extent to which processing anomalies in primary sensory cortex extend to other regions or across the two hemispheres is presently unclear. Methods In response to low/high rate and novel tactile stimuli on the affected and unaffected hands, magnetoencephalography (MEG) was used to elaborate activity timing and amplitude in the primary somatosensory (S1) and secondary somatosensory/parietal ventral (S2/PV) cortices. MEG and clinical performance measures were collected from thirteen patients and matched controls. Results Compared to controls, subjects with tspFHD had increased response amplitude in S2/PV bilaterally in response to high rate and novel stimuli. Subjects with tspFHD also showed increased response latency (low rate, novel) of the affected digits in contralateral S1. For high rate, subjects with tspFHD showed increased response latency in ipsilateral S1 and S2/PV bilaterally. Activation differences correlated with functional sensory deficits (predicting a latency shift in S1), motor speed and muscle strength. Conclusions There are objective differences in the amplitude and timing of activity for both hands across contralateral and ipsilateral somatosensory cortex in patients with tspFHD. Significance Knowledge of cortical processing abnormalities across S1 and S2/PV in dystonia should be applied towards the development of learning based sensorimotor interventions. PMID:21802357

  17. Beta and gamma oscillatory activities associated with olfactory memory tasks: different rhythms for different functional networks?

    PubMed Central

    Martin, Claire; Ravel, Nadine

    2014-01-01

    Olfactory processing in behaving animals, even at early stages, is inextricable from top down influences associated with odor perception. The anatomy of the olfactory network (olfactory bulb, piriform, and entorhinal cortices) and its unique direct access to the limbic system makes it particularly attractive to study how sensory processing could be modulated by learning and memory. Moreover, olfactory structures have been early reported to exhibit oscillatory population activities easy to capture through local field potential recordings. An attractive hypothesis is that neuronal oscillations would serve to “bind” distant structures to reach a unified and coherent perception. In relation to this hypothesis, we will assess the functional relevance of different types of oscillatory activity observed in the olfactory system of behaving animals. This review will focus primarily on two types of oscillatory activities: beta (15–40 Hz) and gamma (60–100 Hz). While gamma oscillations are dominant in the olfactory system in the absence of odorant, both beta and gamma rhythms have been reported to be modulated depending on the nature of the olfactory task. Studies from the authors of the present review and other groups brought evidence for a link between these oscillations and behavioral changes induced by olfactory learning. However, differences in studies led to divergent interpretations concerning the respective role of these oscillations in olfactory processing. Based on a critical reexamination of those data, we propose hypotheses on the functional involvement of beta and gamma oscillations for odor perception and memory. PMID:25002840

  18. Astronomy for a Better World: IAU OAD Task Force-1 Programs for Advancing Astronomy Education and Research in Universities in Developing Countries

    NASA Astrophysics Data System (ADS)

    Guinan, Edward; Kolenberg, Katrien

    2015-03-01

    We discuss the IAU Commission 46 and Office for Astronomy Development (OAD) programs that support advancing Astronomy education and research primarily in universities in developing countries. The bulk of these operational activities will be coordinated through the OAD's newly installed Task Force 1. We outline current (and future) IAU/OAD Task Force-1 programs that promote the development of University-level Astronomy at both undergraduate and graduate levels. Among current programs discussed are the past and future expanded activities of the International School for Young Astronomers (ISYA) and the Teaching Astronomy for Development (TAD) programs. The primary role of the ISYA program is the organization of a three week School for students for typically M.Sc. and Ph.D students. The ISYA is a very successful program that will now be offered more frequently through the generous support of the Kavli Foundation. The IAU/TAD program provides aid and resources for the development of teaching, education and research in Astronomy. The TAD program is dedicated to assist countries that have little or no astronomical activity, but that wish to develop or enhance Astronomy education. Over the last ten years, the ISYA and TAD programs have supported programs in Africa, Asia, Central America and the Caribbean, the Middle East, South East and West Asia, and South America. Several examples are given. Several new programs being considered by OAD Task Force-1 are also discussed. Other possible programs being considered are the introduction of modular Astronomy courses into the university curricula (or improve present courses) as well as providing access to ``remote learning`` courses and Virtual Astronomy labs in developing countries. Another possible new program would support visits of astronomers from technically advanced countries to spend their sabbatical leaves teaching and advising University Astronomy programs in developing countries. Suggestions for new Task Force -1

  19. The HIV/AIDS epidemic in sub-Saharan Africa: thinking ahead on programmatic tasks and related operational research

    PubMed Central

    2011-01-01

    Until now, we have all been desperately trying to run behind the HIV/AIDS epidemic and catch up with it, but despite all our efforts, the epidemic remains well ahead of us. In 2010, the antiretroviral treatment (ART) gap was about 60%, AIDS-related deaths were almost two million a year, and on top of these figures, for every one person started on ART, there were two new HIV infections. What is needed to change this situation is to think ahead of the epidemic in terms of the programmatic tasks we will be faced with and try to act boldly in trying to implement those tasks. From a programmatic perspective, we: a) highlight what needs to fundamentally change in our thinking and overall approach to the epidemic; and b) outline a number of key task areas for implementation and related operational research. PMID:21967983

  20. The HIV/AIDS epidemic in sub-Saharan Africa: thinking ahead on programmatic tasks and related operational research.

    PubMed

    Zachariah, Rony; Van Damme, Wim; Arendt, Vic; Schmit, Jean Claude; Harries, Anthony D

    2011-01-01

    Until now, we have all been desperately trying to run behind the HIV/AIDS epidemic and catch up with it, but despite all our efforts, the epidemic remains well ahead of us. In 2010, the antiretroviral treatment (ART) gap was about 60%, AIDS-related deaths were almost two million a year, and on top of these figures, for every one person started on ART, there were two new HIV infections. What is needed to change this situation is to think ahead of the epidemic in terms of the programmatic tasks we will be faced with and try to act boldly in trying to implement those tasks. From a programmatic perspective, we: a) highlight what needs to fundamentally change in our thinking and overall approach to the epidemic; and b) outline a number of key task areas for implementation and related operational research.

  1. Task-specific stability in muscle activation space during unintentional movements.

    PubMed

    Falaki, Ali; Towhidkhah, Farzad; Zhou, Tao; Latash, Mark L

    2014-11-01

    We used robot-generated perturbations applied during position-holding tasks to explore stability of induced unintentional movements in a multidimensional space of muscle activations. Healthy subjects held the handle of a robot against a constant bias force and were instructed not to interfere with hand movements produced by changes in the external force. Transient force changes were applied leading to handle displacement away from the initial position and then back toward the initial position. Intertrial variance in the space of muscle modes (eigenvectors in the muscle activations space) was quantified within two subspaces, corresponding to unchanged handle coordinate and to changes in the handle coordinate. Most variance was confined to the former subspace in each of the three phases of movement, the initial steady state, the intermediate position, and the final steady state. The same result was found when the changes in muscle activation were analyzed between the initial and final steady states. Changes in the dwell time between the perturbation force application and removal led to different final hand locations undershooting the initial position. The magnitude of the undershot scaled with the dwell time, while the structure of variance in the muscle activation space did not depend on the dwell time. We conclude that stability of the hand coordinate is ensured during both intentional and unintentional actions via similar mechanisms. Relative equifinality in the external space after transient perturbations may be associated with varying states in the redundant space of muscle activations. The results fit a hierarchical scheme for the control of voluntary movements with referent configurations and redundant mapping between the levels of the hierarchy. PMID:25092272

  2. TASK-SPECIFIC STABILITY IN MUSCLE ACTIVATION SPACE DURING UNINTENTIONAL MOVEMENTS

    PubMed Central

    Falaki, Ali; Towhidkhah, Farzad; Zhou, Tao; Latash, Mark L.

    2014-01-01

    We used robot-generated perturbations applied during position-holding tasks to explore stability of induced unintentional movements in a multi-dimensional space of muscle activations. Healthy subjects held the handle of a robot against a constant bias force and were instructed not to interfere with hand movements produced by changes in the external force. Transient force changes were applied leading to handle displacement away from the initial position and then back towards the initial position. Inter-trial variance in the space of muscle modes (eigenvectors in the muscle activations space) was quantified within two sub-spaces, corresponding to unchanged handle coordinate and to changes in the handle coordinate. Most variance was confined to the former sub-space in each of the three phases of movement, the initial steady state, the intermediate position, and the final steady state. The same result was found when the changes in muscle activation were analyzed between the initial and final steady states. Changes in the dwell time between the perturbation force application and removal led to different final hand locations undershooting the initial position. The magnitude of the undershot scaled with the dwell time, while the structure of variance in the muscle activation space did not depend on the dwell time. We conclude that stability of the hand coordinate is ensured during both intentional and unintentional actions via similar mechanisms. Relative equifinality in the external space after transient perturbations may be associated with varying states in the redundant space of muscle activations. The results fit a hierarchical scheme for the control of voluntary movements with referent configurations and redundant mapping between the levels of the hierarchy. PMID:25092272

  3. Comparison of active and purely visual performance in a multiple-string means-end task in infants.

    PubMed

    Rat-Fischer, Lauriane; O'Regan, J Kevin; Fagard, Jacqueline

    2014-10-01

    The aim of the present study was to understand what factors influence infants' problem-solving behaviours on the multiple-string task. The main question focused on why infants usually solve the single string-pulling task at 12months at the latest, whereas most 16-month-old infants still cannot solve the task when several strings are presented, only one of which is attached to the desired object. We investigated whether this difficulty is related to infants' ability to inhibit their spontaneous immediate actions by comparing active and purely visual performance in this task. During the first part of the experiment, we assessed the ability of infants aged 16-20months to solve the multiple-string task. The infants were then divided into three groups based on performance (a "failure" group, an "intermediate" group, and a "success" group). The results of this action task suggest that there were differences in infants' performance according to their level of inhibitory control of their preferred hand. In the second part of the experiment, the three groups' predictive looking strategies were compared when seeing an adult performing the task. We found that only infants who successfully performed the action task also visually anticipated which string the adult had to pull in the visual task. Our results suggests that inhibitory control was not the only factor influencing infants' performance on the task. Furthermore, the data support the direct matching hypothesis (Rizzolatti and Fadiga, 2005), according to which infants need to be able to perform actions themselves before being able to anticipate similar actions performed by others.

  4. 38 CFR 1.488 - Research activities.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PROVISIONS Disclosures Without Patient Consent § 1.488 Research activities. Subject to the provisions of 38 U.S.C. 5701, 38 CFR 1.500-1.527, the Privacy Act (5 U.S.C. 552a), 38 CFR 1.575-1.584 and the following... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Research activities....

  5. 38 CFR 1.488 - Research activities.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROVISIONS Disclosures Without Patient Consent § 1.488 Research activities. Subject to the provisions of 38 U.S.C. 5701, 38 CFR 1.500-1.527, the Privacy Act (5 U.S.C. 552a), 38 CFR 1.575-1.584 and the following... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Research activities....

  6. Teacher management behaviors and pupil task involvement during small group laboratory activities

    NASA Astrophysics Data System (ADS)

    Beasley, Warren

    A major concern of many beginning and experienced teachers is that of classroom management and control. This article describes recent research into defining classroom management procedures that are used by high school science teachers and their relationship to pupil ontaskness. The classroom is conceptualized as a manipulable behavioral system. This construct arises directly from Barker's (1968) ecological psychology, the classroom and its occupants being conceptualized as a behavior setting. The behaviors of the teacher and the pupils are an integral part of the unit (behavior setting), which in turn coerces certain behaviors from its participants. Thus settings, and, in particular, subsettings, are seen as more important determiners of social behavior than the personality of individual teacher or pupil. The methodology employed in this research has involved the extensive use of video in naturalistic science classrooms. Tapes of both teacher and pupil behaviors were continuously and independently recorded. Intensive analysis using electronic recording instruments interfaced with the computer has allowed the collection and sophisticated analysis of the observational data. Data relating to teacher management behavior in small group settings have been analyzed and the relationships to pupil task involvement have been explored.

  7. Optimization of Muscle Activity for Task-Level Goals Predicts Complex Changes in Limb Forces across Biomechanical Contexts

    PubMed Central

    McKay, J. Lucas; Ting, Lena H.

    2012-01-01

    Optimality principles have been proposed as a general framework for understanding motor control in animals and humans largely based on their ability to predict general features movement in idealized motor tasks. However, generalizing these concepts past proof-of-principle to understand the neuromechanical transformation from task-level control to detailed execution-level muscle activity and forces during behaviorally-relevant motor tasks has proved difficult. In an unrestrained balance task in cats, we demonstrate that achieving task-level constraints center of mass forces and moments while minimizing control effort predicts detailed patterns of muscle activity and ground reaction forces in an anatomically-realistic musculoskeletal model. Whereas optimization is typically used to resolve redundancy at a single level of the motor hierarchy, we simultaneously resolved redundancy across both muscles and limbs and directly compared predictions to experimental measures across multiple perturbation directions that elicit different intra- and interlimb coordination patterns. Further, although some candidate task-level variables and cost functions generated indistinguishable predictions in a single biomechanical context, we identified a common optimization framework that could predict up to 48 experimental conditions per animal (n = 3) across both perturbation directions and different biomechanical contexts created by altering animals' postural configuration. Predictions were further improved by imposing experimentally-derived muscle synergy constraints, suggesting additional task variables or costs that may be relevant to the neural control of balance. These results suggested that reduced-dimension neural control mechanisms such as muscle synergies can achieve similar kinetics to the optimal solution, but with increased control effort (≈2×) compared to individual muscle control. Our results are consistent with the idea that hierarchical, task-level neural control

  8. Optimization of muscle activity for task-level goals predicts complex changes in limb forces across biomechanical contexts.

    PubMed

    McKay, J Lucas; Ting, Lena H

    2012-01-01

    Optimality principles have been proposed as a general framework for understanding motor control in animals and humans largely based on their ability to predict general features movement in idealized motor tasks. However, generalizing these concepts past proof-of-principle to understand the neuromechanical transformation from task-level control to detailed execution-level muscle activity and forces during behaviorally-relevant motor tasks has proved difficult. In an unrestrained balance task in cats, we demonstrate that achieving task-level constraints center of mass forces and moments while minimizing control effort predicts detailed patterns of muscle activity and ground reaction forces in an anatomically-realistic musculoskeletal model. Whereas optimization is typically used to resolve redundancy at a single level of the motor hierarchy, we simultaneously resolved redundancy across both muscles and limbs and directly compared predictions to experimental measures across multiple perturbation directions that elicit different intra- and interlimb coordination patterns. Further, although some candidate task-level variables and cost functions generated indistinguishable predictions in a single biomechanical context, we identified a common optimization framework that could predict up to 48 experimental conditions per animal (n = 3) across both perturbation directions and different biomechanical contexts created by altering animals' postural configuration. Predictions were further improved by imposing experimentally-derived muscle synergy constraints, suggesting additional task variables or costs that may be relevant to the neural control of balance. These results suggested that reduced-dimension neural control mechanisms such as muscle synergies can achieve similar kinetics to the optimal solution, but with increased control effort (≈2×) compared to individual muscle control. Our results are consistent with the idea that hierarchical, task-level neural control

  9. Teaching Research Methodology through Active Learning

    ERIC Educational Resources Information Center

    Lundahl, Brad W.

    2008-01-01

    To complement traditional learning activities in a masters-level research methodology course, social work students worked on a formal research project which involved: designing the study, constructing measures, selecting a sampling strategy, collecting data, reducing and analyzing data, and finally interpreting and communicating the results. The…

  10. The Positive Impact of Creative Activity: Effects of Creative Task Engagement and Motivational Focus on College Students' Learning.

    ERIC Educational Resources Information Center

    Conti, Regina; And Others

    1995-01-01

    Assessed effectiveness of engaging students in a creative activity on a topic as a means of encouraging an active cognitive set toward learning that topic area. Creative task engagement was found to be an effective means of enhancing creativity (in the absence of evaluation expectation), intrinsic motivation, and long-term retention. (JBJ)

  11. Research on safety evaluation model for in-vehicle secondary task driving.

    PubMed

    Jin, Lisheng; Xian, Huacai; Niu, Qingning; Bie, Jing

    2015-08-01

    This paper presents a new method for evaluating in-vehicle secondary task driving safety. There are five in-vehicle distracter tasks: tuning the radio to a local station, touching the touch-screen telephone menu to a certain song, talking with laboratory assistant, answering a telephone via Bluetooth headset, and finding the navigation system from Ipad4 computer. Forty young drivers completed the driving experiment on a driving simulator. Measures of fixations, saccades, and blinks are collected and analyzed. Based on the measures of driver eye movements which have significant difference between the baseline and secondary task driving conditions, the evaluation index system is built. The Analytic Network Process (ANP) theory is applied for determining the importance weight of the evaluation index in a fuzzy environment. On the basis of the importance weight of the evaluation index, Fuzzy Comprehensive Evaluation (FCE) method is utilized to evaluate the secondary task driving safety. Results show that driving with secondary tasks greatly distracts the driver's attention from road and the evaluation model built in this study could estimate driving safety effectively under different driving conditions.

  12. TASK-3 knockout mice exhibit exaggerated nocturnal activity, impairments in cognitive functions, and reduced sensitivity to inhalation anesthetics.

    PubMed

    Linden, Anni-Maija; Sandu, Cristina; Aller, M Isabel; Vekovischeva, Olga Y; Rosenberg, Per H; Wisden, William; Korpi, Esa R

    2007-12-01

    The TASK-3 channel is an acid-sensitive two-pore-domain K+ channel, widely expressed in the brain and probably involved in regulating numerous neuronal populations. Here, we characterized the behavioral and pharmacological phenotypes of TASK-3 knockout (KO) mice. Circadian locomotor activity measurements revealed that the nocturnal activity of the TASK-3 KO mice was increased by 38% (P < 0.01) compared with wild-type littermate controls, light phase activity being similar. Although TASK-3 channels are abundant in cerebellar granule cells, the KO mice performed as well as the wild-type mice in walking on a rotating rod or along a 1.2-cm-diameter beam. However, they fell more frequently from a narrower 0.8-cm beam. The KO mice showed impaired working memory in the spontaneous alternation task, with the alternation percentage being 62 +/- 3% for the wild-type mice and 48 +/- 4% (P < 0.05) for the KO mice. Likewise, during training for the Morris water-maze spatial memory task, the KO mice were slower to find the hidden platform, and in the probe trial, the female KO mice visited fewer times the platform quadrant than the male KO and wild-type mice. In pharmacological tests, the TASK-3 KO mice showed reduced sensitivity to the inhalation anesthetic halothane and the cannabinoid receptor agonist WIN55212-2 mesylate [(R)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl)pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphthalenylmethanone mesylate] but unaltered responses to the alpha2 adrenoceptor agonist dexmedetomidine, the i.v. anesthetic propofol, the opioid receptor agonist morphine, and the local anesthetic lidocaine. Overall, our results suggest important contributions of TASK-3 channels in the neuronal circuits regulating circadian rhythms, cognitive functions, and mediating specific pharmacological effects.

  13. TASK-3 knockout mice exhibit exaggerated nocturnal activity, impairments in cognitive functions, and reduced sensitivity to inhalation anesthetics.

    PubMed

    Linden, Anni-Maija; Sandu, Cristina; Aller, M Isabel; Vekovischeva, Olga Y; Rosenberg, Per H; Wisden, William; Korpi, Esa R

    2007-12-01

    The TASK-3 channel is an acid-sensitive two-pore-domain K+ channel, widely expressed in the brain and probably involved in regulating numerous neuronal populations. Here, we characterized the behavioral and pharmacological phenotypes of TASK-3 knockout (KO) mice. Circadian locomotor activity measurements revealed that the nocturnal activity of the TASK-3 KO mice was increased by 38% (P < 0.01) compared with wild-type littermate controls, light phase activity being similar. Although TASK-3 channels are abundant in cerebellar granule cells, the KO mice performed as well as the wild-type mice in walking on a rotating rod or along a 1.2-cm-diameter beam. However, they fell more frequently from a narrower 0.8-cm beam. The KO mice showed impaired working memory in the spontaneous alternation task, with the alternation percentage being 62 +/- 3% for the wild-type mice and 48 +/- 4% (P < 0.05) for the KO mice. Likewise, during training for the Morris water-maze spatial memory task, the KO mice were slower to find the hidden platform, and in the probe trial, the female KO mice visited fewer times the platform quadrant than the male KO and wild-type mice. In pharmacological tests, the TASK-3 KO mice showed reduced sensitivity to the inhalation anesthetic halothane and the cannabinoid receptor agonist WIN55212-2 mesylate [(R)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl)pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphthalenylmethanone mesylate] but unaltered responses to the alpha2 adrenoceptor agonist dexmedetomidine, the i.v. anesthetic propofol, the opioid receptor agonist morphine, and the local anesthetic lidocaine. Overall, our results suggest important contributions of TASK-3 channels in the neuronal circuits regulating circadian rhythms, cognitive functions, and mediating specific pharmacological effects. PMID:17875609

  14. Research on Mobile Learning Activities Applying Tablets

    ERIC Educational Resources Information Center

    Kurilovas, Eugenijus; Juskeviciene, Anita; Bireniene, Virginija

    2015-01-01

    The paper aims to present current research on mobile learning activities in Lithuania while implementing flagship EU-funded CCL project on application of tablet computers in education. In the paper, the quality of modern mobile learning activities based on learning personalisation, problem solving, collaboration, and flipped class methods is…

  15. [Research activities in Kobe-Indonesia Collaborative Research Centers].

    PubMed

    Utsumi, Takako; Hayashi, Yoshitake; Hotta, Hak

    2013-01-01

    Kobe-Indonesia Collaborative Research Center was established in Institute of Tropical Disease (ITD), Airlangga University, Surabaya, Indonesia in 2007 under the program of ''Founding Research Centers for Emerging and Reemerging Infectious Diseases'' supported by the Ministry of Education, Culture, Sports, Science and Technology, Japan, and then it has been under the Japan Initiative for Global Research Network on Infectious Diseases (J-GRID) since 2010. Japanese researchers have been stationed at ITD, conducting joint researches on influenza, viral hepatitis, dengue and infectious diarrhea. Also, another Japanese researcher has been stationed at Faculty of Medicine, University of Indonesia, Jakarta, carrying out joint researches on'' Identification of anti-hepatitis C virus (HCV) substances and development of HCV and dengue vaccines'' in collaboration with University of Indonesia and Airlangga University through the Science and Technology Research Partnership for Sustainable Development (SATREPS) supported by the Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA) since 2009. In this article, we briefly introduce the background history of Kobe University Research Center in Indonesia, and discuss the research themes and outcomes of J-GRID and SATREPS activities.

  16. Activation of the dentate nucleus in a verb generation task: A 7T MRI study.

    PubMed

    Thürling, M; Küper, M; Stefanescu, R; Maderwald, S; Gizewski, E R; Ladd, M E; Timmann, D

    2011-08-01

    There is increasing evidence of a topographic organization within the human cerebellar cortex for motor and non-motor functions. Likewise, a subdivision of the dentate nucleus in a more dorsal and rostral motor domain and a more ventral and caudal non-motor domain has been proposed by Dum and Strick (2003) based on anatomical studies in monkey. In humans, however, very little is known about topographic organization within the dentate nucleus. Activation of the dentate nucleus in a verb generation task was examined in young and healthy subjects using ultra-highfield 7T functional magnetic resonance imaging (fMRI) with its increase in signal-to-noise ratio. Data of 17 subjects were included in statistical analysis. Subjects were asked to (i) read words (nouns) aloud presented on a screen, (ii) silently read the same nouns, (iii) silently generate the appropriate verbs to the same nouns and (iv) to silently repeat the names of the months. A block design was used. For image processing, a recently developed region of interest (ROI) driven normalization method of the dentate nuclei was applied. Activation related to motor speech (contrast aloud reading minus silent reading) was strongest in the rostral parts of the dentate nucleus. Dorsorostral activations were present bilaterally. Activation related to verb generation (contrast verb generation minus silent reading) was found in the ventrocaudal parts of the dentate nucleus on the right. The present findings are in good accordance with the anatomical data in monkeys and suggest that the human dentate nucleus can be subdivided into a rostral and more dorsal motor domain and a ventrocaudal non-motor domain. PMID:21640191

  17. Activation and tremor of the shoulder muscles to the demands of an archery task.

    PubMed

    Lin, Jiu-Jenq; Hung, Cheng-Ju; Yang, Ching-Ching; Chen, Hsing-Yu; Chou, Feng-Ching; Lu, Tung-Wu

    2010-02-01

    Physiological tremor and strength during the maintenance of shoulder position occur during a precision aiming task, such as archery. It is unclear how positions for precision demands affect physiological tremor and associated muscular activities. The purpose of this study was to assess the tremor amplitude and muscular activities of the shoulder between the various positions for precision demands. Ten males (age 21.9 +/- 2.0 years) participated in the study. Electromyography (EMG) was quantified on eight humeral/scapular muscles. The tremor was measured by the acceleration component of a motion tracking sensor in the 3-7 Hz and 8-12 Hz frequency bands. Participants simulated six preparatory archery shooting positions (3 arm angles x 2 arm draw positions) and performed isometric contractions. The relative root mean square (RMS) amplitudes of the shoulder muscles were significantly greater for the full drawing position compared with the partial position (humeral muscles: P = 0.011; scapular muscles: P = 0.026). In the full drawing position, increased humeral/scapular muscle EMG amplitude was moderately associated with an increased power spectrum of 8-12/3-7 Hz tremor in humerus/scapula motion (R = 0.43-0.57). To minimize fluctuations in high strength muscle performance, 90 degrees of elevation in the full drawing position may be a suitable position for demands in archery. In addition, scapular muscle amplitude is important for stability to reduce humerus tremor during archery performance. PMID:20432134

  18. Relationship between simulated extravehicular activity tasks and measurements of physical performance.

    PubMed

    Ade, C J; Broxterman, R M; Craig, J C; Schlup, S J; Wilcox, S L; Barstow, T J

    2014-11-01

    The purpose was to evaluate the relationships between tests of fitness and two activities that simulate components of Lunar- and Martian-based extravehicular activities (EVA). Seventy-one subjects completed two field tests: a physical abilities test and a 10km Walkback test. The relationships between test times and the following parameters were determined: running V˙O2max, gas exchange threshold (GET), speed at V˙O2max (s-V˙O2max), highest sustainable rate of aerobic metabolism [critical speed (CS)], and the finite distance that could be covered above CS (D'): arm cranking V˙O2peak, GET, critical power (CP), and the finite work that can be performed above CP (W'). CS, running V˙O2max, s-V˙O2max, and arm cranking V˙O2peak had the highest correlations with the physical abilities field test (r=0.66-0.82, P<0.001). For the 10km Walkback, CS, s-V˙O2max, and running V˙O2max were significant predictors (r=0.64-0.85, P<0.001). CS and to a lesser extent V˙O2max are most strongly associated with tasks that simulate aspects of EVA performance, highlighting CS as a method for evaluating astronaut physical capacity.

  19. Correlation between prefrontal cortex activity during working memory tasks and natural mood independent of personality effects: an optical topography study.

    PubMed

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

    2013-04-30

    Interactions between mood and cognition have drawn much attention in the fields of psychology and neuroscience. Recent neuroimaging studies have examined a neural basis of the mood-cognition interaction that which emphasize the role of the prefrontal cortex (PFC). Although these studies have shown that natural mood variations among participants are correlated with PFC activity during cognitive tasks, they did not control for personality differences. Our aim in this study was to clarify the relationship between natural mood and PFC activity by partialling out the effects of personality. Forty healthy adults completed self-report questionnaires assessing natural mood (the Profile of Mood States) and personality (the NEO Five-Factor Inventory and the Behavioral Inhibition/Activation Systems scales). They performed verbal and spatial working memory (WM) tasks while their PFC activity was measured using optical topography, a non-invasive, low-constraint neuroimaging tool. Correlation analysis showed that the level of negative mood was inversely associated with PFC activity during the verbal WM task, which replicated our previous findings. Furthermore, the negative correlation between negative mood and PFC activity remained significant after controlling for participants' personality traits, suggesting that natural mood is an independent contributing factor of PFC activity during verbal WM tasks.

  20. Task-dependent and polarity-specific effects of prefrontal transcranial direct current stimulation on cortical activation during word fluency.

    PubMed

    Ehlis, Ann-Christine; Haeussinger, Florian B; Gastel, Alex; Fallgatter, Andreas J; Plewnia, Christian

    2016-10-15

    Targeted modulation of cortical functions by non-invasive brain stimulation is widely used for the investigation of the neurophysiological signatures of executive functions and put forward as a potential specific treatment for its disorders. To further investigate the underlying mechanisms, we performed two experiments involving 46 subjects that performed a semantic and a phonological verbal fluency task (VFT) as well as a simple speech-production task after application of 1mA anodal or cathodal transcranial direct current stimulation (tDCS) to the left inferior frontal gyrus (IFG). Brain activation was measured by functional near-infrared spectroscopy (fNIRS) during task performance. Neither preceding anodal nor cathodal tDCS was found to modulate VFT performance of either difficulty. However, preconditioning with anodal tDCS increased brain activity during the VFT whereas a trendwise decrease of activation was found after cathodal stimulation. Notably, this difference was not found with simple speech production. These findings support the notion of a polarity-specific malleability of neuronal network activity underlying speech production by tDCS. Most importantly, the task-specificity of the modulatory effect observed after the end of stimulation demonstrates lasting neurophysiological effects of tDCS that are reflected in modifications of cortical excitability by challenging cognitive tasks. PMID:26748077

  1. Covert motor activity on NoGo trials in a task sharing paradigm: evidence from the lateralized readiness potential.

    PubMed

    Holländer, Antje; Jung, Christina; Prinz, Wolfgang

    2011-06-01

    Previous studies on task sharing propose that a representation of the co-actor's task share is generated when two actors share a common task. An important function of co-representation seems to lie in the anticipation of others' upcoming actions, which is essential for one's own action planning, as it enables the rapid selection of an appropriate response. We utilized measures of lateralized motor activation, the lateralized readiness potential (LRP), in a task sharing paradigm to address the questions (1) whether the generation of a co-representation involves motor activity in the non-acting person when it is other agent's turn to respond, and (2) whether co-representation of the other's task share is generated from one's own egocentric perspective or from the perspective of the actor (allocentric). Results showed that although it was the other agent's turn to respond, the motor system of the non-acting person was activated prior to the other's response. Furthermore, motor activity was based on egocentric spatial properties. The findings support the tight functional coupling between one's own actions and actions produced by others, suggesting that the involvement of the motor system is crucial for social interaction.

  2. Performance evaluation of nonnegative matrix factorization algorithms to estimate task-related neuronal activities from fMRI data.

    PubMed

    Ding, Xiaoyu; Lee, Jong-Hwan; Lee, Seong-Whan

    2013-04-01

    Nonnegative matrix factorization (NMF) is a blind source separation (BSS) algorithm which is based on the distinct constraint of nonnegativity of the estimated parameters as well as on the measured data. In this study, according to the potential feasibility of NMF for fMRI data, the four most popular NMF algorithms, corresponding to the following two types of (1) least-squares based update [i.e., alternating least-squares NMF (ALSNMF) and projected gradient descent NMF] and (2) multiplicative update (i.e., NMF based on Euclidean distance and NMF based on divergence cost function), were investigated by using them to estimate task-related neuronal activities. These algorithms were applied firstly to individual data from a single subject and, subsequently, to group data sets from multiple subjects. On the single-subject level, although all four algorithms detected task-related activation from simulated data, the performance of multiplicative update NMFs was significantly deteriorated when evaluated using visuomotor task fMRI data, for which they failed in estimating any task-related neuronal activities. In group-level analysis on both simulated data and real fMRI data, ALSNMF outperformed the other three algorithms. The presented findings may suggest that ALSNMF appears to be the most promising option among the tested NMF algorithms to extract task-related neuronal activities from fMRI data.

  3. Research Activity and the Association with Mortality

    PubMed Central

    Ozdemir, Baris A.; Karthikesalingam, Alan; Sinha, Sidhartha; Poloniecki, Jan D.; Hinchliffe, Robert J.; Thompson, Matt M.; Gower, Jonathan D.; Boaz, Annette; Holt, Peter J. E.

    2015-01-01

    Introduction The aims of this study were to describe the key features of acute NHS Trusts with different levels of research activity and to investigate associations between research activity and clinical outcomes. Methods National Institute for Health Research (NIHR) Comprehensive Clinical Research Network (CCRN) funding and number of patients recruited to NIHR Clinical Research Network (CRN) portfolio studies for each NHS Trusts were used as markers of research activity. Patient-level data for adult non-elective admissions were extracted from the English Hospital Episode Statistics (2005-10). Risk-adjusted mortality associations between Trust structures, research activity and, clinical outcomes were investigated. Results Low mortality Trusts received greater levels of funding and recruited more patients adjusted for size of Trust (n = 35, 2,349 £/bed [95% CI 1,855–2,843], 5.9 patients/bed [2.7–9.0]) than Trusts with expected (n = 63, 1,110 £/bed, [864–1,357] p<0.0001, 2.6 patients/bed [1.7–3.5] p<0.0169) or, high (n = 42, 930 £/bed [683–1,177] p = 0.0001, 1.8 patients/bed [1.4–2.1] p<0.0005) mortality rates. The most research active Trusts were those with more doctors, nurses, critical care beds, operating theatres and, made greater use of radiology. Multifactorial analysis demonstrated better survival in the top funding and patient recruitment tertiles (lowest vs. highest (odds ratio & 95% CI: funding 1.050 [1.033–1.068] p<0.0001, recruitment 1.069 [1.052–1.086] p<0.0001), middle vs. highest (funding 1.040 [1.024–1.055] p<0.0001, recruitment 1.085 [1.070–1.100] p<0.0001). Conclusions Research active Trusts appear to have key differences in composition than less research active Trusts. Research active Trusts had lower risk-adjusted mortality for acute admissions, which persisted after adjustment for staffing and other structural factors. PMID:25719608

  4. Modeling good research practices--overview: a report of the ISPOR-SMDM Modeling Good Research Practices Task Force--1.

    PubMed

    Caro, J Jaime; Briggs, Andrew H; Siebert, Uwe; Kuntz, Karen M

    2012-01-01

    Models--mathematical frameworks that facilitate estimation of the consequences of health care decisions--have become essential tools for health technology assessment. Evolution of the methods since the first ISPOR Modeling Task Force reported in 2003 has led to a new Task Force, jointly convened with the Society for Medical Decision Making, and this series of seven articles presents the updated recommendations for best practices in conceptualizing models; implementing state-transition approaches, discrete event simulations, or dynamic transmission models; and dealing with uncertainty and validating and reporting models transparently. This overview article introduces the work of the Task Force, provides all the recommendations, and discusses some quandaries that require further elucidation. The audience for these articles includes those who build models, stakeholders who utilize their results, and, indeed, anyone concerned with the use of models to support decision making. PMID:22999128

  5. Modeling good research practices--overview: a report of the ISPOR-SMDM Modeling Good Research Practices Task Force-1.

    PubMed

    Caro, J Jaime; Briggs, Andrew H; Siebert, Uwe; Kuntz, Karen M

    2012-01-01

    Models-mathematical frameworks that facilitate estimation of the consequences of health care decisions-have become essential tools for health technology assessment. Evolution of the methods since the first ISPOR modeling task force reported in 2003 has led to a new task force, jointly convened with the Society for Medical Decision Making, and this series of seven papers presents the updated recommendations for best practices in conceptualizing models; implementing state-transition approaches, discrete event simulations, or dynamic transmission models; dealing with uncertainty; and validating and reporting models transparently. This overview introduces the work of the task force, provides all the recommendations, and discusses some quandaries that require further elucidation. The audience for these papers includes those who build models, stakeholders who utilize their results, and, indeed, anyone concerned with the use of models to support decision making. PMID:22990082

  6. Modeling good research practices--overview: a report of the ISPOR-SMDM Modeling Good Research Practices Task Force--1.

    PubMed

    Caro, J Jaime; Briggs, Andrew H; Siebert, Uwe; Kuntz, Karen M

    2012-01-01

    Models--mathematical frameworks that facilitate estimation of the consequences of health care decisions--have become essential tools for health technology assessment. Evolution of the methods since the first ISPOR Modeling Task Force reported in 2003 has led to a new Task Force, jointly convened with the Society for Medical Decision Making, and this series of seven articles presents the updated recommendations for best practices in conceptualizing models; implementing state-transition approaches, discrete event simulations, or dynamic transmission models; and dealing with uncertainty and validating and reporting models transparently. This overview article introduces the work of the Task Force, provides all the recommendations, and discusses some quandaries that require further elucidation. The audience for these articles includes those who build models, stakeholders who utilize their results, and, indeed, anyone concerned with the use of models to support decision making.

  7. Modeling good research practices--overview: a report of the ISPOR-SMDM Modeling Good Research Practices Task Force-1.

    PubMed

    Caro, J Jaime; Briggs, Andrew H; Siebert, Uwe; Kuntz, Karen M

    2012-01-01

    Models-mathematical frameworks that facilitate estimation of the consequences of health care decisions-have become essential tools for health technology assessment. Evolution of the methods since the first ISPOR modeling task force reported in 2003 has led to a new task force, jointly convened with the Society for Medical Decision Making, and this series of seven papers presents the updated recommendations for best practices in conceptualizing models; implementing state-transition approaches, discrete event simulations, or dynamic transmission models; dealing with uncertainty; and validating and reporting models transparently. This overview introduces the work of the task force, provides all the recommendations, and discusses some quandaries that require further elucidation. The audience for these papers includes those who build models, stakeholders who utilize their results, and, indeed, anyone concerned with the use of models to support decision making.

  8. Mathematical Tasks as a Framework for Reflection: From Research To Practice.

    ERIC Educational Resources Information Center

    Stein, Mary Kay; Smith, Margaret Schwan

    1998-01-01

    Describes the Quantitative Understanding: Amplifying Student Achievement and Reasoning (QUASAR) national reform project aimed at studying and fostering the development and implementation of enhanced mathematics instructional programs. It is a framework for reflection based on mathematical tasks used during classroom instruction and the ways in…

  9. Children's Reading Task by Gender Interactions: Implications for Research and Practice.

    ERIC Educational Resources Information Center

    Kincade, Kay M.; Kleine, Paul F.

    A study examined the effect of gender, age, and cognitive task on three types of reading recall. Subjects, 40 boys and girls in the second grade and 40 in the fifth grade from a suburban Northeast school system, all reading at or above grade level, performed cued or free recall on four high-interest short stories. Reading recall was assessed via…

  10. Common Threads in Behavior Checklists, Task Analysis, Prompting, Operations Training, and Chaining Research.

    ERIC Educational Resources Information Center

    Walls, Richard T.

    The paper reviews studies on performance objectives, task analysis, and prompting and instruction sequences as they relate to the education of handicapped students. The initial section, on performance objectives, reviews the development of the Vocational Behavior Checklist and the Subsequent Independent Living Behavior Checklist. The next step in…

  11. Linguistic Proficiency Assessment in Second Language Acquisition Research: The Elicited Imitation Task

    ERIC Educational Resources Information Center

    Gaillard, Stéphanie; Tremblay, Annie

    2016-01-01

    This study investigated the elicited imitation task (EIT) as a tool for measuring linguistic proficiency in a second/foreign (L2) language, focusing on French. Nonnative French speakers (n = 94) and native French speakers (n = 6) completed an EIT that included 50 sentences varying in length and complexity. Three raters evaluated productions on…

  12. Teachers, Tasks, and Tensions: Lessons from a Research-Practice Partnership

    ERIC Educational Resources Information Center

    Johnson, Raymond; Severance, Samuel; Penuel, William R.; Leary, Heather

    2016-01-01

    How teachers make sense of new academic standards significantly shapes the implementation of those standards. Professional development organized around the analysis of mathematical tasks has potential to prepare teachers for standards implementation by helping them develop common understandings of standards and how to help students meet ambitious…

  13. National facilities study. Volume 2: Task group on aeronautical research and development facilities report

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Task Group on Aeronautics R&D Facilities examined the status and requirements for aeronautics facilities against the competitive need. Emphasis was placed on ground-based facilities for subsonic, supersonic and hypersonic aerodynamics, and propulsion. Subsonic and transonic wind tunnels were judged to be most critical and of highest priority. Results of the study are presented.

  14. Functional MRI approach for assessing hemispheric predominance of regions activated by a phonological and a semantic task.

    PubMed

    Cousin, Emilie; Peyrin, Carole; Pichat, Cédric; Lamalle, Laurent; Le Bas, Jean-François; Baciu, Monica

    2007-08-01

    This fMRI study performed in healthy subjects aimed at using a statistical approach in order to determine significant functional differences between hemispheres and to assess specialized regions activated during a phonological and during a semantic task. This approach ("flip" method and subsequent statistical analyses of the parameter estimates extracted from regions of interest) allows identifying: (a) hemispheric specialized regions for each language task [semantic (living categorization) and phonological (rhyme detection)] and (b) condition-specific regions with respect to paradigm conditions (task and control). Our results showed that the rhyme-specific task regions were the inferior frontal (sub-region of BA 44, 45) and left inferior parietal (BA 40, 39) lobules. Furthermore, within the inferior parietal lobule, the angular gyrus was specific to target (rhyming) items (related to successfully grapho-phonemic processing). The categorization-specific task regions were the left inferior frontal (sub-region of BA 44, 45) and superior temporal (BA 22) cortices. Furthermore, the superior temporal gyrus was related to non-target (non-living) items (correlated to task difficulty). The relatively new approach used in this study has the advantage of providing: (a) statistical significance of the hemispheric specialized regions for a given language task and (b) supplementary information in terms of paradigm condition-specificity of the activated regions. The results (standard hemispheric specialized regions for a semantic and for a phonological task) obtained in healthy subjects may constitute a basement for mapping language and assessing hemispheric predominance in epileptic patients before surgery and avoiding post-surgical impairments of language. PMID:17339089

  15. Discriminant analysis in schizophrenia and healthy subjects using prefrontal activation during frontal lobe tasks: a near-infrared spectroscopy.

    PubMed

    Azechi, Michiyo; Iwase, Masao; Ikezawa, Koji; Takahashi, Hidetoshi; Canuet, Leonides; Kurimoto, Ryu; Nakahachi, Takayuki; Ishii, Ryouhei; Fukumoto, Motoyuki; Ohi, Kazutaka; Yasuda, Yuka; Kazui, Hiroaki; Hashimoto, Ryota; Takeda, Masatoshi

    2010-03-01

    While psychiatric disorders such as schizophrenia are largely diagnosed on symptomatology, several studies have attempted to determine which biomarkers can discriminate schizophrenia patients from non-patients with schizophrenia. The objective of this study is to assess whether near-infrared spectroscopy (NIRS) measurement can distinguish schizophrenia patients from healthy subjects. Sixty patients with schizophrenia and sixty age- and gender-matched healthy controls were divided into two sequential groups. The concentration change in oxygenated hemoglobin (Delta[oxy-Hb]) was measured in the bilateral prefrontal areas (Fp1-F7 and Fp2-F8) during the Verbal Fluency Test (VFT) letter version and category version, Tower of Hanoi (TOH), Sternberg's (SBT) and Stroop Tasks. In the first group, schizophrenia patients showed poorer task performance on all tasks and less prefrontal cortex activation during all but the Stroop Task compared to healthy subjects. In the second group, schizophrenia patients showed poorer task performance and less prefrontal cortex activation during VFTs and TOH tasks than healthy subjects. We then performed discriminant analysis by a stepwise method using Delta[oxy-Hb] and task performance measures as independent variables. The discriminant analysis in the first group included task performance of TOH, VFT letter and VFT category and Delta[oxy-Hb] of VFT letter. As a result, 88.3% of the participants were correctly classified as being schizophrenic or healthy subjects in the first analysis. The discriminant function derived from the first group correctly assigned 75% of the subjects in the second group. Our findings suggest that NIRS measurement could be applied to differentiate patients with schizophrenia from healthy subjects. PMID:19896332

  16. Byurakan Astrophysical Observatory: Active Researches of the Activity Phenomena

    NASA Astrophysics Data System (ADS)

    Harutyunian, H. A.

    2016-09-01

    Scientific research directions elaborated at the Byurakan astrophysical observatory (BAO) since its foundation are reviewed briefly. Although the wide spectrum of research at BAO we have focused attention on the activity phenomena mainly. Indisputable proof of the existence of newborn stars, as well as the activity phenomena in the galactic nuclei are mentioned as the main scientific attainments of the BAO. These two scientific breakthroughs undoubtedly had also very essential conceptual significance which is not yet estimated at its true worth. Some conceptual changes accompanying the discovery of the accelerated expansion of the Universe are considered from the cosmic objects' activity viewpoint.

  17. A preliminary fMRI study of a novel self-paced written fluency task: observation of left-hemispheric activation, and increased frontal activation in late vs. early task phases

    PubMed Central

    Golestanirad, Laleh; Das, Sunit; Schweizer, Tom A.; Graham, Simon J.

    2015-01-01

    Neuropsychological tests of verbal fluency are very widely used to characterize impaired cognitive function. For clinical neuroscience studies and potential medical applications, measuring the brain activity that underlies such tests with functional magnetic resonance imaging (fMRI) is of significant interest—but a challenging proposition because overt speech can cause signal artifacts, which tend to worsen as the duration of speech tasks becomes longer. In a novel approach, we present the group brain activity of 12 subjects who performed a self-paced written version of phonemic fluency using fMRI-compatible tablet technology that recorded responses and provided task-related feedback on a projection screen display, over long-duration task blocks (60 s). As predicted, we observed robust activation in the left anterior inferior and medial frontal gyri, consistent with previously reported results of verbal fluency tasks which established the role of these areas in strategic word retrieval. In addition, the number of words produced in the late phase (last 30 s) of written phonemic fluency was significantly less (p < 0.05) than the number produced in the early phase (first 30 s). Activation during the late phase vs. the early phase was also assessed from the first 20 s and last 20 s of task performance, which eliminated the possibility that the sluggish hemodynamic response from the early phase would affect the activation estimates of the late phase. The last 20 s produced greater activation maps covering extended areas in bilateral precuneus, cuneus, middle temporal gyrus, insula, middle frontal gyrus and cingulate gyrus. Among these areas, greater activation was observed in the bilateral middle frontal gyrus (Brodmann area BA 9) and cingulate gyrus (BA 24, 32) likely as part of the initiation, maintenance, and shifting of attentional resources. Consistent with previous pertinent fMRI literature involving overt and covert verbal responses, these findings highlight

  18. A preliminary fMRI study of a novel self-paced written fluency task: observation of left-hemispheric activation, and increased frontal activation in late vs. early task phases.

    PubMed

    Golestanirad, Laleh; Das, Sunit; Schweizer, Tom A; Graham, Simon J

    2015-01-01

    Neuropsychological tests of verbal fluency are very widely used to characterize impaired cognitive function. For clinical neuroscience studies and potential medical applications, measuring the brain activity that underlies such tests with functional magnetic resonance imaging (fMRI) is of significant interest-but a challenging proposition because overt speech can cause signal artifacts, which tend to worsen as the duration of speech tasks becomes longer. In a novel approach, we present the group brain activity of 12 subjects who performed a self-paced written version of phonemic fluency using fMRI-compatible tablet technology that recorded responses and provided task-related feedback on a projection screen display, over long-duration task blocks (60 s). As predicted, we observed robust activation in the left anterior inferior and medial frontal gyri, consistent with previously reported results of verbal fluency tasks which established the role of these areas in strategic word retrieval. In addition, the number of words produced in the late phase (last 30 s) of written phonemic fluency was significantly less (p < 0.05) than the number produced in the early phase (first 30 s). Activation during the late phase vs. the early phase was also assessed from the first 20 s and last 20 s of task performance, which eliminated the possibility that the sluggish hemodynamic response from the early phase would affect the activation estimates of the late phase. The last 20 s produced greater activation maps covering extended areas in bilateral precuneus, cuneus, middle temporal gyrus, insula, middle frontal gyrus and cingulate gyrus. Among these areas, greater activation was observed in the bilateral middle frontal gyrus (Brodmann area BA 9) and cingulate gyrus (BA 24, 32) likely as part of the initiation, maintenance, and shifting of attentional resources. Consistent with previous pertinent fMRI literature involving overt and covert verbal responses, these findings highlight the

  19. Increased brain cortical activity during parabolic flights has no influence on a motor tracking task.

    PubMed

    Schneider, Stefan; Brümmer, Vera; Mierau, Andreas; Carnahan, Heather; Dubrowski, Adam; Strüder, Heiko K

    2008-03-01

    Previous studies showed that changing forces of gravity as they typically occur during parabolic flights might be responsible for adaptional processes of the CNS. However, until now it has not been differentiated between primary influences of weightlessness and secondary influences due to psycho-physiological factors (e.g., physical or mental strain). With the aim of detecting parabolic flight related changes in central cortical activity, a resting EEG was deduced in 16 subjects before, during and after parabolic flights. After subdividing EEG into alpha-, beta-,delta- and theta-wave bands, an increase in beta-power was noticeable inflight, whereas alpha(1)-power was increased postflight. No changes could be observed for the control group. To control possible effects of cortical activation, a manual tracking task with mirror inversion was performed during either the phase of weightlessness or during the normal gravity phase of a parabolic flight. No differences in performance nor in adaptation could be observed between both groups. A third group, performing under normal and stress-free conditions in a lab showed similar tracking values. We assume that the specific increase in brain activity is a sign of an increase in arousal inflight. This does support previous assumptions of non-specific stressors during parabolic flights and has to be considered as a relevant factor for experiments on central nerve adaptation. Although no influences of stress and/or weightlessness on motor performance and adaptation could be observed, we suggest that an "inflight" control group seems to be more adequate than a laboratory control group to investigate gravity-dependent changes in motor control.

  20. Task-induced brain activity in aphasic stroke patients: what is driving recovery?

    PubMed

    Geranmayeh, Fatemeh; Brownsett, Sonia L E; Wise, Richard J S

    2014-10-01

    attributed to activity in 'language networks' occupying sites not observed in healthy participants. In this review we will argue that much of the distribution of what has often been interpreted as language-specific activity, particularly in midline and contralateral cortical regions, is an upregulation of activity in intact domain-general systems for cognitive control and attention, responding in a task-dependent manner to the increased 'effort' when damaged downstream domain-specific language networks are impaired. We further propose that it is an inability fully to activate these systems that may result in sub optimal recovery in some patients. Interpretation of the data in terms of activity in domain-general networks affords insights into novel approaches to rehabilitation.

  1. Prediction of human actions: expertise and task-related effects on neural activation of the action observation network.

    PubMed

    Balser, Nils; Lorey, Britta; Pilgramm, Sebastian; Stark, Rudolf; Bischoff, Matthias; Zentgraf, Karen; Williams, Andrew Mark; Munzert, Jörn

    2014-08-01

    The action observation network (AON) is supposed to play a crucial role when athletes anticipate the effect of others' actions in sports such as tennis. We used functional magnetic resonance imaging to explore whether motor expertise leads to a differential activation pattern within the AON during effect anticipation and whether spatial and motor anticipation tasks are associated with a differential activation pattern within the AON depending on participant expertise level. Expert (N=16) and novice (N=16) tennis players observed video clips depicting forehand strokes with the instruction to either indicate the predicted direction of ball flight (spatial anticipation) or to decide on an appropriate response to the observed action (motor anticipation). The experts performed better than novices on both tennis anticipation tasks, with the experts showing stronger neural activation in areas of the AON, namely, the superior parietal lobe, the intraparietal sulcus, the inferior frontal gyrus, and the cerebellum. When novices were contrasted with experts, motor anticipation resulted in stronger activation of the ventral premotor cortex, the supplementary motor area, and the superior parietal lobe than spatial anticipation task did. In experts, the comparison of motor and spatial anticipation revealed no increased activation. We suggest that the stronger activation of areas in the AON during the anticipation of action effects in experts reflects their use of the more fine-tuned motor representations they have acquired and improved during years of training. Furthermore, results suggest that the neural processing of different anticipation tasks depends on the expertise level.

  2. Collaborative Construction of Task Activity: Coordinating Multiple Resources in a High School Physics Lab.

    ERIC Educational Resources Information Center

    Ford, Cecilia E.

    1999-01-01

    Documents the collaborative coordination of multiple resources--talk, gesture, and writing--as represented in the interaction among three high school seniors working on a physics laboratory task. Through close analysis of the moment-to-moment construction of task, the study draws attention to complex yet taken-for-granted practices that are…

  3. Enhancing Reading Comprehension through Task-Based Writing Activities: An Experimental Study

    ERIC Educational Resources Information Center

    Tilfarlioglu, Filiz Yalcin; Basaran, Suleyman

    2007-01-01

    Task-based learning is a popular topic in ELT/EFL circles nowadays. It is accepted by its proponents as a flourishing method that may replace Communicative Language Learning. However, it can also be seen as an adventure just because there are almost no experimental studies to tackle questions concerning applicability of Task-based Learning. In…

  4. Brain Activity toward Gaming-Related Cues in Internet Gaming Disorder during an Addiction Stroop Task

    PubMed Central

    Zhang, Yifen; Lin, Xiao; Zhou, Hongli; Xu, Jiaojing; Du, Xiaoxia; Dong, Guangheng

    2016-01-01

    Background and Aims: Attentional bias for drug-related stimuli is a key characteristic for drug addiction. Characterizing the relationship between attentional bias and brain reactivity to Internet gaming-related stimuli may help in identifying the neural substrates that critical to Internet gaming disorder (IGD). Methods: 19 IGD and 21 healthy control (HC) subjects were scanned with functional magnetic resonance imaging while they were performing an addiction Stroop task. Results: Compared with HC group, IGD subjects showed higher activations when facing Internet gaming-related stimuli in regions including the inferior parietal lobule, the middle occipital gyrus and the dorsolateral prefrontal cortex. These brain areas were thought to be involved in selective attention, visual processing, working memory and cognitive control. Discussion and Conclusions: The results demonstrated that compared with HC group, IGD subjects show impairment in both visual and cognitive control ability while dealing with gaming-related words. This finding might be helpful in understanding the underlying neural basis of IGD. PMID:27242623

  5. Task-specific Dystonias

    PubMed Central

    Torres-Russotto, Diego; Perlmutter, Joel S.

    2009-01-01

    Task-specific dystonias are primary focal dystonias characterized by excessive muscle contractions producing abnormal postures during selective motor activities that often involve highly skilled, repetitive movements. Historically these peculiar postures were considered psychogenic but have now been classified as forms of dystonia. Writer’s cramp is the most commonly identified task-specific dystonia and has features typical of this group of disorders. Symptoms may begin with lack of dexterity during performance of a specific motor task with increasingly abnormal posturing of the involved body part as motor activity continues. Initially, the dystonia may manifest only during the performance of the inciting task, but as the condition progresses it may also occur during other activities or even at rest. Neurological exam is usually unremarkable except for the dystonia-related abnormalities. Although the precise pathophysiology remains unclear, increasing evidence suggests reduced inhibition at different levels of the sensorimotor system. Symptomatic treatment options include oral medications, botulinum toxin injections, neurosurgical procedures, and adaptive strategies. Prognosis may vary depending upon body part involved and specific type of task affected. Further research may reveal new insights into the etiology, pathophysiology, natural history, and improved treatment of these conditions. PMID:18990127

  6. The Health Services Mobility Study Method of Task Analysis and Curriculum Design. Research Report No. 11. Volume 4: Developing Curriculum Objectives from Task Data: A Manual.

    ERIC Educational Resources Information Center

    Gilpatrick, Eleanor; Gullion, Christina

    This document is volume 4 of a four-volume report which describes the components of the Health Services Mobility Study (HSMS) method of task analysis, job ladder design, and curriculum development. Divided into three chapters, volume 4 is a manual for using HSMS task data and analysis results to develop curriculum objectives, guidelines, and…

  7. Comparison of functional magnetic resonance imaging in cerebral activation between normal Uygur and Mandarin participants in semantic identification task

    PubMed Central

    Xi, Yan-Ling; Tian, Qing; Tuerxun, Tuerhong; Kaheman, Kuerbannaimu; Jiang, Chun-Hui; Huang, Hai-Xia; Wang, Bao-Lan

    2015-01-01

    Purpose: This study utilized blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) technology to study the activated cerebral regions in normal participants whose native language was Uyghur or Chinese. Methods: We collected the fMRI data from 15 Uyghur-speaking volunteers and 15 Mandarin-speaking volunteers when executing the semantic identification task and compared the results of two groups. Results: Statistically significant difference of brain activation was found primarily in the left anterior cingulate gyrus (BA23) and the midline precuneus (P<0.05). When performing the semantic identification task, the Uyghur group exhibited significant activation in these two regions, whereas the Chinese group demonstrated relatively weak activation in these areas. Conclusion: The cerebral regions activated by Uyghur and Chinese semantic identification are not identical, the dominant hemisphere for both languages is the left cerebral hemisphere. The left anterior cingulate gyrus might have a language function in Uyghur semantic processing. PMID:26550318

  8. An overview of Japanese CELSS research activities.

    PubMed

    Nitta, K

    1987-01-01

    Many research activities regarding Controlled Ecological Life Support System (CELSS) have been conducted and continued all over the world since the 1960's and the concept of CELSS is now changing from Science Fiction to Scientific Reality. Development of CELSS technology is inevitable for future long duration stays of human beings in space, for lunar base construction and for manned mars flight programs. CELSS functions can be divided into two categories, Environment Control and Material Recycling. Temperature, humidity, total atmospheric pressure and partial pressure of oxygen and carbon dioxide, necessary for all living things, are to be controlled by the environment control function. This function can be performed by technologies already developed and used as the Environment Control Life Support System (ECLSS) of Space Shuttle and Space Station. As for material recycling, matured technologies have not yet been established for fully satisfying the specific metabolic requirements of each living thing including human beings. Therefore, research activities for establishing CELSS technology should be focused on material recycling technologies using biological systems such as plants and animals and physico-chemical systems, for example, a gas recycling system, a water purifying and recycling system and a waste management system. Based on these considerations, Japanese research activities have been conducted and will be continued under the tentative guideline of CELSS research activities as shown in documents /1/, /2/. The status of the over all activities are discussed in this paper.

  9. Whole-brain, time-locked activation with simple tasks revealed using massive averaging and model-free analysis

    PubMed Central

    Gonzalez-Castillo, Javier; Saad, Ziad S.; Handwerker, Daniel A.; Inati, Souheil J.; Brenowitz, Noah; Bandettini, Peter A.

    2012-01-01

    The brain is the body's largest energy consumer, even in the absence of demanding tasks. Electrophysiologists report on-going neuronal firing during stimulation or task in regions beyond those of primary relationship to the perturbation. Although the biological origin of consciousness remains elusive, it is argued that it emerges from complex, continuous whole-brain neuronal collaboration. Despite converging evidence suggesting the whole brain is continuously working and adapting to anticipate and actuate in response to the environment, over the last 20 y, task-based functional MRI (fMRI) have emphasized a localizationist view of brain function, with fMRI showing only a handful of activated regions in response to task/stimulation. Here, we challenge that view with evidence that under optimal noise conditions, fMRI activations extend well beyond areas of primary relationship to the task; and blood-oxygen level-dependent signal changes correlated with task-timing appear in over 95% of the brain for a simple visual stimulation plus attention control task. Moreover, we show that response shape varies substantially across regions, and that whole-brain parcellations based on those differences produce distributed clusters that are anatomically and functionally meaningful, symmetrical across hemispheres, and reproducible across subjects. These findings highlight the exquisite detail lying in fMRI signals beyond what is normally examined, and emphasize both the pervasiveness of false negatives, and how the sparseness of fMRI maps is not a result of localized brain function, but a consequence of high noise and overly strict predictive response models. PMID:22431587

  10. Differences in cortical activity between methamphetamine-dependent and healthy individuals performing a facial affect matching task.

    PubMed

    Payer, Doris E; Lieberman, Matthew D; Monterosso, John R; Xu, Jiansong; Fong, Timothy W; London, Edythe D

    2008-01-11

    As individuals who abuse methamphetamine (MA) often exhibit socially maladaptive behaviors such as violence and aggression, it is possible that they respond abnormally to social cues. To investigate this issue, we exposed 12 MA-dependent participants (abstinent 5-16 days) and 12 healthy comparison participants to fearful and angry faces while they performed an affect matching task during functional magnetic resonance imaging (fMRI). Although the groups did not differ in task performance, the healthy participants showed more task-related activity than the MA-dependent participants in a set of cortical regions consisting of the ventrolateral prefrontal cortex (VLPFC), temporoparietal junction (TPJ), anterior and posterior temporal cortex, and fusiform gyrus in the right hemisphere, and the cuneus in the left hemisphere. In contrast, the MA-dependent participants showed more task-related activity than the healthy participants in the dorsal anterior cingulate cortex (dACC). As expected, the task elicited activation of the amygdala in both groups; however, contrary to expectation, we found no difference between groups in this activation. Dorsal ACC hyperactivity, along with high self-ratings of hostility and interpersonal sensitivity in the MA-dependent group, suggest a hyper-sensitivity to socially threatening cues in the MA-dependent participants, while lower VLPFC activation could point to a deficit in integrating socio-emotional information and/or regulating this limbic hyperactivity. Additional activation differences in neural circuitry related to social cognition (TPJ, anterior, and posterior temporal cortex) suggest further socio-emotional deficits. Together, the results point to cortical abnormalities that could underlie the socially inappropriate behaviors often shown by individuals who abuse MA. PMID:17964741

  11. Comparison of brain activation patterns during executive function tasks in hoarding disorder and non-hoarding OCD.

    PubMed

    Hough, Christina M; Luks, Tracy L; Lai, Karen; Vigil, Ofilio; Guillory, Sylvia; Nongpiur, Arvind; Fekri, Shiva M; Kupferman, Eve; Mathalon, Daniel H; Mathews, Carol A

    2016-09-30

    We examined differences in regional brain activation during tests of executive function in individuals with Hoarding Disorder (HD), Obsessive Compulsive Disorder (OCD), and healthy controls (HC) using functional magnetic resonance imaging (fMRI). Participants completed computerized versions of the Stroop and Go/No-Go task. We found that during the conflict monitoring and response inhibition condition in the Go/No-Go task, individuals with HD had significantly greater activity than controls in the anterior cingulate cortex (ACC) and right dorsolateral prefrontal cortex (DLPFC). HD also exhibited significantly greater right DLPFC activity than OCD. We also observed significant differences in activity between HD and HC and between HD and OCD in regions (ACC, anterior insula, orbitofrontal cortex, and striatum) involved in evaluating stimulus-response-reward associations, or the personal and task-relevant value of stimuli and behavioral responses to stimuli. These results support the hypothesis that individuals with HD have difficulty deciding on the value or task relevance of stimuli, and may perceive an abnormally high risk of negative feedback for difficult or erroneous cognitive behavior. PMID:27522332

  12. Active Tasks to Change the Use of Class Time within an Outcomes Based Approach to Curriculum Design

    ERIC Educational Resources Information Center

    Salter, Diane; Pang, Marco Y. C.; Sharma, Piyush

    2009-01-01

    This paper describes how new roles for instructors and learners can be integrated into course design and delivery by rethinking course design as part of a process-based staff development program. The goal of incorporating online learning tasks was to engage students with course resources prior to class time through active learning. The staff…

  13. Brain Activity in Adults Who Stutter: Similarities across Speaking Tasks and Correlations with Stuttering Frequency and Speaking Rate

    ERIC Educational Resources Information Center

    Ingham, Roger J.; Grafton, Scott T.; Bothe, Anne K.; Ingham, Janis C.

    2012-01-01

    Many differences in brain activity have been reported between persons who stutter (PWS) and typically fluent controls during oral reading tasks. An earlier meta-analysis of imaging studies identified stutter-related regions, but recent studies report less agreement with those regions. A PET study on adult dextral PWS (n = 18) and matched fluent…

  14. The Effects of Preferred Activities during Academic Work Breaks on Task Engagement and Negatively Reinforced Destructive Behavior.

    ERIC Educational Resources Information Center

    McComas, Jennifer J.; Goddard, Carol; Hoch, Hannah

    2002-01-01

    Destructive behavior of 9-year-old with learning disabilities was evaluated in a functional analysis. The effects of extinction, negative reinforcement, and negative reinforcement combined with access to preferred activities were compared on behavior and task engagement. Engagement occurred most and destructive behavior occurred least when…

  15. Control processes through the suppression of the automatic response activation triggered by task-irrelevant information in the Simon-type tasks.

    PubMed

    Kim, Sanga; Lee, Sang Ho; Cho, Yang Seok

    2015-11-01

    The congruency sequence effect, one of the indices of cognitive control, refers to a smaller congruency effect after an incongruent than congruent trial. Although the effect has been found across a variety of conflict tasks, there is not yet agreement on the underlying mechanism. The present study investigated the mechanism underlying cognitive control by using a cross-task paradigm. In Experiments 1, 2, and 3, participants performed a modified Simon task and a spatial Stroop task alternately in a trial-by-trial manner. The task-irrelevant dimension of the two tasks was perceptually and conceptually identical in Experiment 1, whereas it was perceptually different but conceptually identical in Experiment 2. The response sets for both tasks were different in Experiment 3. In Experiment 4, participants performed two Simon tasks with different task-relevant dimensions. In all experiments in which the task-irrelevant dimension and response mode were shared, significant congruency sequence effects were found between the two different congruencies, indicating that Simon-type conflicts were resolved by a control mechanism, which is specific to an abstract task-irrelevant stimulus spatial dimension. PMID:26479902

  16. On the Need of Objective Vigilance Monitoring: Effects of Sleep Loss on Target Detection and Task-Negative Activity Using Combined EEG/fMRI

    PubMed Central

    Czisch, Michael; Wehrle, Renate; Harsay, Helga A.; Wetter, Thomas C.; Holsboer, Florian; Sämann, Philipp G.; Drummond, Sean P. A.

    2012-01-01

    Sleep loss affects attention by reducing levels of arousal and alertness. The neural mechanisms underlying the compensatory efforts of the brain to maintain attention and performance after sleep deprivation (SD) are not fully understood. Previous neuroimaging studies of SD have not been able to separate the effects of reduced arousal from the effects of SD on cerebral responses to cognitive challenges. Here, we used a simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) approach to study the effects of 36 h of total sleep deprivation (TSD). Specifically, we focused on changes in selective attention processes as induced by an active acoustic oddball task, with the ability to isolate runs with objective EEG signs of high (SDalert) or reduced (SDsleepy) vigilance. In the SDalert condition, oddball task-related activity appears to be sustained by compensatory co-activation of insular regions, but task-negative activity in the right posterior node of the default mode network is altered following TSD. In the SDsleepy condition, oddball task-positive activity was massively impaired, but task-negative activation was showing levels comparable with the control condition after a well-rested night. Our results suggest that loss of strict negative correlation between oddball task-positive and task-negative activation reflects the effects of TSD, while the actual state of vigilance during task performance can affects either task-related or task-negative activity, depending on the exact vigilance level. PMID:22557992

  17. Ongoing brain activity fluctuations directly account for intertrial and indirectly for intersubject variability in Stroop task performance.

    PubMed

    Coste, Clio P; Sadaghiani, Sepideh; Friston, Karl J; Kleinschmidt, Andreas

    2011-11-01

    Recent studies have established a relation between ongoing brain activity fluctuations and intertrial variability in evoked neural responses, perception, and motor performance. Here, we extended these investigations into the domain of cognitive control. Using functional neuroimaging and a sparse event-related design (with long and unpredictable intervals), we measured ongoing activity fluctuations and evoked responses in volunteers performing a Stroop task with color-word interference. Across trials, prestimulus activity of several regions predicted subsequent response speed and across subjects this effect scaled with the Stroop effect size, being significant only in subjects manifesting behavioral interference. These effects occurred only in task relevant as the dorsal anterior cingulate and dorsolateral prefrontal cortex as well as ventral visual areas sensitive to color and visual words. Crucially, in subjects showing a Stroop effect, reaction times were faster when prestimulus activity was higher in task-relevant (color) regions and slower when activity was higher in irrelevant (word form) regions. These findings suggest that intrinsic brain activity fluctuations modulate neural mechanisms underpinning selective voluntary attention and cognitive control. Rephrased in terms of predictive coding models, ongoing activity can hence be considered a proxy of the precision (gain) with which prediction error signals are transmitted upon sensory stimulation.

  18. Brain activation during dual-task processing is associated with cardiorespiratory fitness and performance in older adults

    PubMed Central

    Wong, Chelsea N.; Chaddock-Heyman, Laura; Voss, Michelle W.; Burzynska, Agnieszka Z.; Basak, Chandramallika; Erickson, Kirk I.; Prakash, Ruchika S.; Szabo-Reed, Amanda N.; Phillips, Siobhan M.; Wojcicki, Thomas; Mailey, Emily L.; McAuley, Edward; Kramer, Arthur F.

    2015-01-01

    Higher cardiorespiratory fitness is associated with better cognitive performance and enhanced brain activation. Yet, the extent to which cardiorespiratory fitness-related brain activation is associated with better cognitive performance is not well understood. In this cross-sectional study, we examined whether the association between cardiorespiratory fitness and executive function was mediated by greater prefrontal cortex activation in healthy older adults. Brain activation was measured during dual-task performance with functional magnetic resonance imaging in a sample of 128 healthy older adults (59–80 years). Higher cardiorespiratory fitness was associated with greater activation during dual-task processing in several brain areas including the anterior cingulate and supplementary motor cortex (ACC/SMA), thalamus and basal ganglia, right motor/somatosensory cortex and middle frontal gyrus, and left somatosensory cortex, controlling for age, sex, education, and gray matter volume. Of these regions, greater ACC/SMA activation mediated the association between cardiorespiratory fitness and dual-task performance. We provide novel evidence that cardiorespiratory fitness may support cognitive performance by facilitating brain activation in a core region critical for executive function. PMID:26321949

  19. Research and technology activities at Ames Research Center's Biomedical Research Division

    NASA Technical Reports Server (NTRS)

    Martello, N.

    1985-01-01

    Various research and technology activities at Ames Research Center's Biomedical Research Division are described. Contributions to the Space Administration's goals in the life sciences include descriptions of research in operational medicine, cardiovascular deconditioning, motion sickness, bone alterations, muscle atrophy, fluid and electrolyte changes, radiation effects and protection, behavior and performance, gravitational biology, and life sciences flight experiments.

  20. 42 CFR 2.52 - Research activities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Research activities. 2.52 Section 2.52 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CONFIDENTIALITY OF ALCOHOL AND DRUG ABUSE PATIENT RECORDS Disclosures Without Patient Consent § 2.52...

  1. 42 CFR 2.52 - Research activities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Research activities. 2.52 Section 2.52 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CONFIDENTIALITY OF ALCOHOL AND DRUG ABUSE PATIENT RECORDS Disclosures Without Patient Consent § 2.52...

  2. 42 CFR 2.52 - Research activities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Research activities. 2.52 Section 2.52 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CONFIDENTIALITY OF ALCOHOL AND DRUG ABUSE PATIENT RECORDS Disclosures Without Patient Consent § 2.52...

  3. 42 CFR 2.52 - Research activities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Research activities. 2.52 Section 2.52 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CONFIDENTIALITY OF ALCOHOL AND DRUG ABUSE PATIENT RECORDS Disclosures Without Patient Consent § 2.52...

  4. Oral methylphenidate normalizes cingulate activity in cocaine addiction during a salient cognitive task

    SciTech Connect

    Goldstein, R.Z.; Goldstein, R.Z.; Woicik, P.A.; Maloney, T.; Tomasi, D.; Alia-Klein, N.; Shan, J.; Honorario, J.; Samaras, d.; Wang, R.; Telang, F.; Wang, G.-J.; Volkow, N.D.

    2010-09-21

    Anterior cingulate cortex (ACC) hypoactivations during cognitive demand are a hallmark deficit in drug addiction. Methylphenidate (MPH) normalizes cortical function, enhancing task salience and improving associated cognitive abilities, in other frontal lobe pathologies; however, in clinical trials, MPH did not improve treatment outcome in cocaine addiction. We hypothesized that oral MPH will attenuate ACC hypoactivations and improve associated performance during a salient cognitive task in individuals with cocaine-use disorders (CUD). In the current functional MRI study, we used a rewarded drug cue-reactivity task previously shown to be associated with hypoactivations in both major ACC subdivisions (implicated in default brain function) in CUD compared with healthy controls. The task was performed by 13 CUD and 14 matched healthy controls on 2 d: after ingesting a single dose of oral MPH (20 mg) or placebo (lactose) in a counterbalanced fashion. Results show that oral MPH increased responses to this salient cognitive task in both major ACC subdivisions (including the caudal-dorsal ACC and rostroventromedial ACC extending to the medial orbitofrontal cortex) in the CUD. These functional MRI results were associated with reduced errors of commission (a common impulsivity measure) and improved task accuracy, especially during the drug (vs. neutral) cue-reactivity condition in all subjects. The clinical application of such MPH-induced brain-behavior enhancements remains to be tested.

  5. Quantifying familial influences on brain activation during the monetary incentive delay task: An adolescent monozygotic twin study

    PubMed Central

    Silverman, Merav H.; Krueger, Robert F.; Iacono, William G.; Malone, Stephen M.; Hunt, Ruskin H.; Thomas, Kathleen M.

    2014-01-01

    Although altered brain activation during reward tasks has been found in a number of heritable psychiatric disorders and health outcomes, the familial nature of reward-related brain activation remains unexplored. In this study, we investigated the degree to which the magnitude of mesocorticolimbic reward system signal intensities in anticipation of reward during the monetary incentive delay (MID) task was similar within forty-six pairs of adolescent, monozygotic twins. Significant within-pair correlations in brain activation during anticipation of gain were found in one third of the 18 reward-related regions investigated. These regions were the right nucleus accumbens, left and right posterior caudate, right anterior caudate, left insula, and anterior cingulate cortex. This serves as evidence for a shared familial contribution to individual differences in reward related brain activity in certain key reward processing regions. PMID:25101864

  6. Corticospinal activity during dual tasking: a systematic review and meta-analysis of TMS literature from 1995 to 2013.

    PubMed

    Corp, Daniel T; Lum, Jarrad A G; Tooley, Gregory A; Pearce, Alan J

    2014-06-01

    This systematic review and meta-analysis was conducted across studies using transcranial magnetic stimulation to investigate corticospinal excitability and inhibition in response to a dual task (DT). Quantitative analysis was performed on eleven controlled studies that had included healthy participants over the age of 18 years. Results showed a small effect size for increased corticospinal excitability for DT conditions (SMD=0.207; p=.217, and a small effect size (SMD=-0.253) demonstrating a significant decrease in corticospinal inhibition for DT conditions (p=.019). Meta-regression demonstrated that neither age, task type, or task prioritisation accounted for the high variability in effect sizes between studies. A number of possible sources of within study bias are identified, which reduced the level of evidence for study findings. The results show overall changes in corticospinal responses between ST and DT conditions; however further research is necessary to investigate variables that could account for differences in corticospinal responses between studies. PMID:24705270

  7. Reduced task-induced variations in the distribution of activity across back muscle regions in individuals with low back pain.

    PubMed

    Falla, Deborah; Gizzi, Leonardo; Tschapek, Marika; Erlenwein, Joachim; Petzke, Frank

    2014-05-01

    This study investigated change in the distribution of lumbar erector spinae muscle activity and pressure pain sensitivity across the low back in individuals with low back pain (LBP) and healthy controls. Surface electromyographic (EMG) signals were recorded from multiple locations over the lumbar erector spinae muscle with a 13×5 grid of electrodes from 19 people with chronic nonspecific LBP and 17 control subjects as they performed a repetitive lifting task. The EMG root mean square (RMS) was computed for each location of the grid to form a map of the EMG amplitude distribution. Pressure pain thresholds (PPT) were recorded before and after the lifting task over a similar area of the back. For the control subjects, the EMG RMS progressively increased more in the caudal region of the lumbar erector spinae during the repetitive task, resulting in a shift in the distribution of muscle activity. In contrast, the distribution of muscle activity remained unaltered in the LBP group despite an overall increase in EMG amplitude. PPT was lower in the LBP group after completion of the repetitive task compared to baseline (average across all locations: pre: 268.0±165.9 kPa; post: 242.0±166.7 kPa), whereas no change in PPT over time was observed for the control group (320.1±162.1 kPa; post: 322.0±179.5 kPa). The results demonstrate that LBP alters the normal adaptation of lumbar erector spinae muscle activity to exercise, which occurs in the presence of exercise-induced hyperalgesia. Reduced variability of muscle activity may have important implications for the provocation and recurrence of LBP due to repetitive tasks.

  8. Cortical activity of skilled performance in a complex sports related motor task.

    PubMed

    Baumeister, Jochen; Reinecke, Kirsten; Liesen, Heinz; Weiss, Michael

    2008-11-01

    A skilled player in goal-directed sports performance has the ability to process internal and external information in an effective manner and decide which pieces of information are important and which are irrelevant. Focused attention and somatosensory information processing play a crucial role in this process. Electroencephalographic (EEG) recordings are able to demonstrate cortical changes in conjunction with this concept and were examined during a golf putting performance in an expert-novice paradigm. The success in putting (score) and performance-related cortical activity were recorded with an EEG during a 5 x 4 min putting series. Subjects were asked to putt balls for four min at their own pace. The EEG data was divided into different frequencies: Theta (4.75-6.75 Hz), Alpha-1 (7-9.5 Hz), Alpha-2 (9.75-12.5 Hz) and Beta-1 (12.75-18.5 Hz) and performance related power values were calculated. Statistical analysis shows significant better performance in the expert golfers (P < 0.001). This was associated with higher fronto-midline Theta power (P < 0.05) and higher parietal Alpha-2 power values (P < 0.05) compared to the novices in golf putting. Frontal Theta and parietal Alpha-2 spectral power in the ongoing EEG demonstrate differences due to skill level. Furthermore the findings suggest that with increasing skill level, golfers have developed task solving strategies including focussed attention and an economy in parietal sensory information processing which lead to more successful performance. In a theoretical framework both cortical parameters may play a role in the concept of the working memory. PMID:18607621

  9. Telerobot task planning and reasoning: Introduction to JPL artificial intelligence research

    NASA Technical Reports Server (NTRS)

    Atkinson, D. J.

    1987-01-01

    A view of the capabilities and areas of artificial intelligence research which are required for autonomous space telerobotics extending through the year 2000 is given. In the coming years, JPL will be conducting directed research to achieve these capabilities, as well as drawing heavily on collaborative efforts conducted with other research laboratories.

  10. Noninvasive imaging of prefrontal activation during attention-demanding tasks performed while walking using a wearable optical topography system

    NASA Astrophysics Data System (ADS)

    Atsumori, Hirokazu; Kiguchi, Masashi; Katura, Takusige; Funane, Tsukasa; Obata, Akiko; Sato, Hiroki; Manaka, Takaaki; Iwamoto, Mitsumasa; Maki, Atsushi; Koizumi, Hideaki; Kubota, Kisou

    2010-07-01

    Optical topography (OT) based on near-infrared spectroscopy is a noninvasive technique for mapping the relative concentration changes in oxygenated and deoxygenated hemoglobin (oxy- and deoxy-Hb, respectively) in the human cerebral cortex. In our previous study, we developed a small and light wearable optical topography (WOT) system that covers the entire forehead for monitoring prefrontal activation. In the present study, we examine whether the WOT system is applicable to OT measurement while walking, which has been difficult with conventional OT systems. We conduct OT measurements while subjects perform an attention-demanding (AD) task of balancing a ping-pong ball on a small card while walking. The measured time course and power spectra of the relative concentration changes in oxy- and deoxy-Hb show that the step-related changes in the oxy- and deoxy-Hb signals are negligible compared to the task-related changes. Statistical assessment of the task-related changes in the oxy-Hb signals show that the dorsolateral prefrontal cortex and rostral prefrontal area are significantly activated during the AD task. These results suggest that our functional imaging technique with the WOT system is applicable to OT measurement while walking, and will be a powerful tool for evaluating brain activation in a natural environment.

  11. Three dimensions of learning: experiential activity for engineering innovation education and research

    NASA Astrophysics Data System (ADS)

    Killen, Catherine P.

    2015-09-01

    This paper outlines a novel approach to engineering education research that provides three dimensions of learning through an experiential class activity. A simulated decision activity brought current research into the classroom, explored the effect of experiential activity on learning outcomes and contributed to the research on innovation decision making. The 'decision task' was undertaken by more than 480 engineering students. It increased their reported measures of learning and retention by an average of 0.66 on a five-point Likert scale, and revealed positive correlations between attention, enjoyment, ongoing interest and learning and retention. The study also contributed to innovation management research by revealing the influence of different data visualisation methods on decision quality, providing an example of research-integrated education that forms part of the research process. Such a dovetailing of different research studies demonstrates how engineering educators can enhance educational impact while multiplying the outcomes from their research efforts.

  12. Self-archiving as researchers' outreach activity

    NASA Astrophysics Data System (ADS)

    Todoroki, Shin-Ichi

    Notable dissemination of two self-archived postprints is reported. Even after three years since the original publication, corresponding postprints were downloaded more than 1,500 times in the following three years. The demands would have probably arisen from the readers who do not subscribe to the journals in which my articles were published. The title of my article might have caught the eyes of researchers in different fields and YouTube viewers of my research video who followed the references I mentioned. Thus, self-archiving is one of the useful approaches for researchers' outreach activities. In order to increase voluntary registrations in their institutional repositories, positive aspects of self-archiving as discussed here should receive wide recognition among researchers and repository systems should provide registrants with quick and informative response to their articles.

  13. Tonic and phasic activation and arousal effects as a function of feedback in repetitive-choice reaction time tasks.

    PubMed

    De Brabander, Bert; Declerck, Carolyn H; Boone, Christophe

    2002-06-01

    This study examines the effects of positive and negative feedback on performance during choice reaction time tasks to assess whether they differentially affect phasic arousal and tonic activation. Participants (N = 96) received either no feedback or signals of reward, punishment, or both during a semantic and a visuospatial repetitive-choice reaction time task. The number of errors made was analyzed both on a trial-by-trial basis and over a continuous series of 80 trials (assessing phasic and tonic feedback effects, respectively). The results show that punishment and reward have different phasic and tonic effects on performance. The data further show that feedback effects interact with the task characteristics: semantic versus visuospatial, and reaction stimulus preceded by a warning signal versus an irrelevant signal. The interaction effects appear to be consistent with the proposed neurological model.

  14. Of "what" and "where" in a natural search task: Active object handling supports object location memory beyond the object's identity.

    PubMed

    Draschkow, Dejan; Võ, Melissa L-H

    2016-08-01

    Looking for as well as actively manipulating objects that are relevant to ongoing behavioral goals are intricate parts of natural behavior. It is, however, not clear to what degree these two forms of interaction with our visual environment differ with regard to their memory representations. In a real-world paradigm, we investigated if physically engaging with objects as part of a search task influences identity and position memory differently for task-relevant versus irrelevant objects. Participants equipped with a mobile eye tracker either searched for cued objects without object interaction (Find condition) or actively collected the objects they found (Handle condition). In the following free-recall task, identity memory was assessed, demonstrating superior memory for relevant compared to irrelevant objects, but no difference between the Handle and Find conditions. Subsequently, location memory was inferred via times to first fixation in a final object search task. Active object manipulation and task-relevance interacted in that location memory for relevant objects was superior to irrelevant ones only in the Handle condition. Including previous object recall performance as a covariate in the linear mixed-model analysis of times to first fixation allowed us to explore the interaction between remembered/forgotten object identities and the execution of location memory. Identity memory performance predicted location memory in the Find but not the Handle condition, suggesting that active object handling leads to strong spatial representations independent of object identity memory. We argue that object handling facilitates the prioritization of relevant location information, but this might come at the cost of deprioritizing irrelevant information. PMID:27165170

  15. Pre- and postnatally administered ACTH, Organon 2766 and CRF facilitate or inhibit active avoidance task performance in young adult mice.

    PubMed

    Honour, L C; White, M H

    1988-01-01

    This study investigated the effect of learning/memory-related neuropeptides on behavioral task performance in later life. A 1 mg/kg dosage of adrenocorticotropic hormone 4-9, Organon 2766, ACTH/MSH 4-10, ACTH 1-24, CRF, or diluent was subcutaneously injected into either pregnant females or into newborn pups during specific neural developmental windows. Each of the progeny was trained in an active-avoidance task and tested for acquisition on postpartum days 35-37. The mice were then tested for memory task performance and reacquisition on days 42-44 postpartum using the identical experimental paradigm as that used in the training sessions. Prenatal treatment with these memory-related neuropeptides resulted in significant facilitation of learning/memory task performance in male and female mice treated with Organon 2766 (p less than 0.001), and a significant inhibition of learning/memory task performance in males and females treated with ACTH 1-24 (p less than 0.01). Additional sex-specific performance facilitations and inhibitions resulted from the pre- or postnatal administration of the various neuropeptides used in this study. These results suggest that neuropeptides, when available in increased amounts during specific neural developmental windows, can significantly improve or suppress related behavioral performance capability in later life.

  16. Combining functional neuroimaging with off-line brain stimulation: modulation of task-related activity in language areas.

    PubMed

    Andoh, Jamila; Paus, Tomás

    2011-02-01

    Repetitive TMS (rTMS) provides a noninvasive tool for modulating neural activity in the human brain. In healthy participants, rTMS applied over the language-related areas in the left hemisphere, including the left posterior temporal area of Wernicke (LTMP) and inferior frontal area of Broca, have been shown to affect performance on word recognition tasks. To investigate the neural substrate of these behavioral effects, off-line rTMS was combined with fMRI acquired during the performance of a word recognition task. Twenty right-handed healthy men underwent fMRI scans before and after a session of 10-Hz rTMS applied outside the magnetic resonance scanner. Functional magnetic resonance images were acquired during the performance of a word recognition task that used English or foreign-language words. rTMS was applied over the LTMP in one group of 10 participants (LTMP group), whereas the homologue region in the right hemisphere was stimulated in another group of 10 participants (RTMP group). Changes in task-related fMRI response (English minus foreign languages) and task performances (response time and accuracy) were measured in both groups and compared between pre-rTMS and post-rTMS. Our results showed that rTMS increased task-related fMRI response in the homologue areas contralateral to the stimulated sites. We also found an effect of rTMS on response time for the LTMP group only. These findings provide insights into changes in neural activity in cortical regions connected to the stimulated site and are consistent with a hypothesis raised in a previous review about the role of the homologue areas in the contralateral hemisphere for preserving behavior after neural interference.

  17. A neural measure of behavioral engagement: task-residual low-frequency blood oxygenation level-dependent activity in the precuneus.

    PubMed

    Zhang, Sheng; Li, Chiang-Shan Ray

    2010-01-15

    Brain imaging has provided a useful tool to examine the neural processes underlying human cognition. A critical question is whether and how task engagement influences the observed regional brain activations. Here we highlighted this issue and derived a neural measure of task engagement from the task-residual low-frequency blood oxygenation level-dependent (BOLD) activity in the precuneus. Using independent component analysis, we identified brain regions in the default circuit - including the precuneus and medial prefrontal cortex (mPFC) - showing greater activation during resting as compared to task residuals in 33 individuals. Time series correlations with the posterior cingulate cortex as the seed region showed that connectivity with the precuneus was significantly stronger during resting as compared to task residuals. We hypothesized that if the task-residual BOLD activity in the precuneus reflects engagement, it should account for a certain amount of variance in task-related regional brain activation. In an additional experiment of 59 individuals performing a stop signal task, we observed that the fractional amplitude of low-frequency fluctuation (fALFF) of the precuneus but not the mPFC accounted for approximately 10% of the variance in prefrontal activation related to attentional monitoring and response inhibition. Taken together, these results suggest that task-residual fALFF in the precuneus may be a potential indicator of task engagement. This measurement may serve as a useful covariate in identifying motivation-independent neural processes that underlie the pathogenesis of a psychiatric or neurological condition.

  18. Relation Between Prefrontal Cortex Activity and Respiratory Rate During Mental Stress Tasks: A Near-Infrared Spectroscopic Study.

    PubMed

    Murayama, Yuta; Hu, Lizhen; Sakatani, Kaoru

    2016-01-01

    In order to clarify the central mechanism controlling respiratory rate during mental stress, we examined the relation between prefrontal cortex (PFC) activity and respiratory rate during mental arithmetic (MA) tasks. Employing two-channel near-infrared spectroscopy (NIRS), we measured hemoglobin (Hb) concentration changes in the bilateral PFC during MA tasks in normal adults. To evaluate asymmetry of the PFC activity, we calculated the laterality index (LI); (R-L)/(R + L) of oxy-Hb concentration changes (R = right, L = left); positive LI scores indicate right-dominant activity, while negative scores indicate left-dominant activity. For measurements of respiratory rate, we employed a Kinect motion sensor (Microsoft). The MA tasks increased both oxy-Hb in the bilateral PFC and respiratory rate (p < 0.001). In addition, there was a significant correlation between LI and respiratory rate (r = 0.582, p < 0.02). These results indicate that the MA-induced activity in the right PFC was greater than that in the left PFC in subjects with large increases of respiratory rate, suggesting that the right PFC has a greater role in cerebral regulation of respiratory rate during mental stress. PMID:27526145

  19. Exposure to childhood trauma is associated with altered n-back activation and performance in healthy adults: implications for a commonly used working memory task

    PubMed Central

    Philip, Noah S.; Sweet, Lawrence H.; Tyrka, Audrey R.; Carpenter, S. Louisa; Albright, Sarah E.; Price, Lawrence H.; Carpenter, Linda L.

    2015-01-01

    Previous research suggests that a history of early life stress (ELS) impacts working memory (WM) in adulthood. Despite the widespread use of WM paradigms, few studies have evaluated whether ELS exposure, in the absence of psychiatric illness, also impacts WM-associated brain activity in ways that might improve sensitivity to these ELS effects or provide insights into the mechanisms of these effects. This study evaluated whether ELS affects WM behavioral performance and task-associated activity by acquiring 3T functional images from 27 medication-free healthy adults (14 with ELS) during an N-back WM task that included 0- and 2-back components. Whole brain voxel-wise analysis was performed to evaluate WM activation, followed by region of interest analyses to evaluate relationships between activation and clinical variables. ELS was associated with poorer accuracy during the 2-back (79 %±19 vs. 92 %±9, p=0.049); accuracy and response time otherwise did not differ between groups. During the 0-back, ELS participants demonstrated increased activation in the superior temporal gyrus/insula, left inferior parietal lobule (IPL) (both corrected p<0.001), and middle temporal and parahippocampal gyrus (MTG/PHG)(corrected p<0.010). During the 2-back, ELS was associated with greater activation in the IPL, MTG/PHG and inferior frontal gyrus (corrected p<0.001), with a trend towards precuneus activation (p=0.080). These findings support previous research showing that ELS is associated with impaired neurobehavioral performance and changes in brain activation, suggesting recruitment of additional cognitive resources during WM in ELS. Based on these findings, ELS screening in future WM imaging studies appears warranted. PMID:25804310

  20. Cardiovascular activity during laboratory tasks in women with high and low worry.

    PubMed

    Knepp, Michael M; Friedman, Bruce H

    2008-12-01

    Worry has been related to delayed stress recovery and cardiovascular disease risk. Cardiovascular responses to a range of laboratory tasks were examined in this study of high and low worriers. Undergraduate women were recruited with the Penn State Worry Questionnaire to form low (n=19) and high (n=22) worry groups. These individuals engaged in six laboratory tasks (orthostatic stress, supine rest, hand cold pressor, mental arithmetic, and worry and relaxation imagery) while heart rate (HR), HR spectral analysis, impedance cardiography, and blood pressure were acquired. The only significant group difference found was a consistently greater HR across tasks in high worriers (p<.05). No group by condition interactions emerged. High trait worry in healthy young women appears to be marked by elevated HR in the absence of autonomic abnormalities. These findings are discussed relative to the literature on worry, with particular reference to its health implications. PMID:18706472

  1. World Psychiatry and the WPA task force to promote dissemination of psychiatric research conducted in low and middle income countries.

    PubMed

    Maj, Mario

    2010-01-01

    World Psychiatry, the official journal of the World Psychiatric Association (WPA), is now published in five languages (English, Spanish, Chinese, Russian and French) and reaches more than 33,000 psychiatrists in 121 countries. It received recently its first impact factor, 3.896. The publication of the journal has two objectives. The first is to reach as many psychiatrists of the various countries of the world as possible, disseminating information on recent significant clinical, service and research developments in a language that can be assimilated by the vast majority of them. The second is to give voice to psychiatrists of all regions of the world, encouraging submission of research papers, commentaries and reports on innovative service modalities. Related to this second objective has been the establishment by the WPA of a task force aiming to promote dissemination of psychiatric research conducted in low and middle income countries. Among the objectives of this task force is to advise and support the editors of high quality journals produced in those countries in their efforts to achieve indexation.

  2. Timing Tasks Synchronize Cerebellar and Frontal Ramping Activity and Theta Oscillations: Implications for Cerebellar Stimulation in Diseases of Impaired Cognition

    PubMed Central

    Parker, Krystal L.

    2016-01-01

    Timing is a fundamental and highly conserved mammalian capability, yet the underlying neural mechanisms are widely debated. Ramping activity of single neurons that gradually increase or decrease activity to encode the passage of time has been speculated to predict a behaviorally relevant temporal event. Cue-evoked low-frequency activity has also been implicated in temporal processing. Ramping activity and low-frequency oscillations occur throughout the brain and could indicate a network-based approach to timing. Temporal processing requires cognitive mechanisms of working memory, attention, and reasoning, which are dysfunctional in neuropsychiatric disease. Therefore, timing tasks could be used to probe cognition in animals with disease phenotypes. The medial frontal cortex and cerebellum are involved in cognition. Cerebellar stimulation has been shown to influence medial frontal activity and improve cognition in schizophrenia. However, the mechanism underlying the efficacy of cerebellar stimulation is unknown. Here, we discuss how timing tasks can be used to probe cerebellar interactions with the frontal cortex and the therapeutic potential of cerebellar stimulation. The goal of this theory and hypothesis manuscript is threefold. First, we will summarize evidence indicating that in addition to motor learning, timing tasks involve cognitive processes that are present within both the cerebellum and medial frontal cortex. Second, we propose methodologies to investigate the connections between these areas in patients with Parkinson’s disease, autism, and schizophrenia. Lastly, we hypothesize that cerebellar transcranial stimulation may rescue medial frontal ramping activity, theta oscillations, and timing abnormalities, thereby restoring executive function in diseases of impaired cognition. This hypothesis could inspire the use of timing tasks as biomarkers for neuronal and cognitive abnormalities in neuropsychiatric disease and promote the therapeutic potential of

  3. Challenges of animal models in SCI research: Effects of pre-injury task-specific training in adult rats before lesion

    PubMed Central

    May, Zacnicte; Fouad, Karim; Shum-Siu, Alice; Magnuson, David S. K.

    2015-01-01

    A rarely explored subject in animal research is the effect of pre-injury variables on behavioural outcome post-SCI. Low reporting of such variables may underlie some discrepancies in findings between laboratories. Particularly, intensive task-specific training before a SCI might be important, considering that sports injuries are one of the leading causes of SCI. Thus, individuals with SCI often underwent rigorous training before their injuries. In the present study, we asked whether training before SCI on a grasping task or a swimming task would influence motor recovery in rats. Swim pre-training impaired recovery of swimming 2 and 4 weeks post-injury. This result fits with the idea of motor learning interference, which posits that learning something new may disrupt learning of a new task; in this case, learning strategies to compensate for functional loss after SCI. In contrast to swimming, grasp pre-training did not influence grasping ability after SCI at any time point. However, grasp pre-trained rats attempted to grasp more times than untrained rats in the first 4 weeks post-injury. Also, lesion volume of grasp pretrained rats was greater than that of untrained rats, a finding which may be related to stress or activity. The increased participation in rehabilitative training of the pre-trained rats in the early weeks post-injury may have potentiated spontaneous plasticity in the spinal cord and counteracted the deleterious effect of interference and bigger lesions. Thus, our findings suggest that pre-training plays a significant role in recovery after CNS damage and needs to be carefully controlled for. PMID:25975172

  4. Coordinating Government Funding of File System and I/O Research through the High End Computing University Research Activity

    SciTech Connect

    Grider, Gary; Nunez, James; Bent, John; Ross, Rob; Ward, Lee; Poole, Steve; Felix, Evan J.; Salmon, Ellen; Bancroft, Marti

    2009-01-01

    In 2003, the High End Computing Revitalization Task Force designated file systems and I/O as an area in need of national focus. The purpose of the High End Computing Interagency Working Group (HECIWG) is to coordinate government spending on File Systems and 1I0 (FSIO) R&D by all the government agencies that are involved in High End Computing. The HECIWG tasked a smaller advisory group to list, categorize, and prioritize HEC VO and File Systems R&D needs. In 2005, leaders in FSIO from academia, industry and government agencies collaborated to Jist and prioritize areas of research in HEC FSIO. This led to a very successful High End Computing University Research Activity (HECURA) call from NSF in 2006 and has prompted a new HECURA call from NSF in 2009. This paper serves as both a review of the 2008 HEC FSIO identified research gaps as well as a preview of this forthcoming HECURA call.

  5. MPD thruster research issues, activities, strategies

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The following activities and plans in the MPD thruster development are summarized: (1) experimental and theoretical research (magnetic nozzles at present and high power levels, MPD thrusters with applied fields extending into the thrust chamber, and improved electrode performance); and (2) tools (MACH2 code for MPD and nozzle flow calculation, laser diagnostics and spectroscopy for non-intrusive measurements of flow conditions, and extension to higher power). National strategies are also outlined.

  6. Research in theoretical elementary particle physics at the University of Florida: Task A. Annual progress report

    SciTech Connect

    Field, R.D.; Ramond, P.M.; Sikivie, P.; Thorn, C.B.

    1994-12-01

    This is the Annual Progress Report of the theoretical particle theory group at the University of Florida under DOE Grant DE-FG05-86ER40272. At present our group consists of four Full Professors (Field, Ramond, Thorn, Sikivie), one Associate Professor (Woodard), and two Assistant Professors (Qiu, Kennedy). In addition, we have four postdoctoral research associates and seven graduate students. The research of our group covers a broad range of topics in theoretical high energy physics including both theory and phenomenology. Included in this report is a summary of the last several years, an outline of our current research program.

  7. TRIGA research reactor activities around the world

    SciTech Connect

    Chesworth, R.H.; Razvi, J.; Whittemore, W.L. )

    1991-11-01

    Recent activities at several overseas TRIGA installations are discussed in this paper, including reactor performance, research programs under way, and plans for future upgrades. The following installations are included: (1) 14,000-kW TRIGA at the Institute for Nuclear Research, Pitesti, Romania; (2) 2,000-kW TRIGA Mark II at the Institute of Nuclear Technology, Dhaka, Bangladesh; (3) 3,000-kW TRIGA conversion, Philippine Nuclear Research Institute, Quezon City, Philippines; and (4) other ongoing installations, including a 1,500-kW TRIGA Mark II at Rabat, Morocco, and a 1,000-kW conversion/upgrade at the Institute Asunto Nucleares, Bogota, Columbia.

  8. Cross-language activation of morphological relatives in cognates: the role of orthographic overlap and task-related processing.

    PubMed

    Mulder, Kimberley; Dijkstra, Ton; Baayen, R Harald

    2015-01-01

    We considered the role of orthography and task-related processing mechanisms in the activation of morphologically related complex words during bilingual word processing. So far, it has only been shown that such morphologically related words (i.e., morphological family members) are activated through the semantic and morphological overlap they share with the target word. In this study, we investigated family size effects in Dutch-English identical cognates (e.g., tent in both languages), non-identical cognates (e.g., pil and pill, in English and Dutch, respectively), and non-cognates (e.g., chicken in English). Because of their cross-linguistic overlap in orthography, reading a cognate can result in activation of family members both languages. Cognates are therefore well-suited for studying mechanisms underlying bilingual activation of morphologically complex words. We investigated family size effects in an English lexical decision task and a Dutch-English language decision task, both performed by Dutch-English bilinguals. English lexical decision showed a facilitatory effect of English and Dutch family size on the processing of English-Dutch cognates relative to English non-cognates. These family size effects were not dependent on cognate type. In contrast, for language decision, in which a bilingual context is created, Dutch and English family size effects were inhibitory. Here, the combined family size of both languages turned out to better predict reaction time than the separate family size in Dutch or English. Moreover, the combined family size interacted with cognate type: the response to identical cognates was slowed by morphological family members in both languages. We conclude that (1) family size effects are sensitive to the task performed on the lexical items, and (2) depend on both semantic and formal aspects of bilingual word processing. We discuss various mechanisms that can explain the observed family size effects in a spreading activation framework.

  9. Associations between depressive symptoms and fronto-temporal activities during a verbal fluency task in patients with schizophrenia

    PubMed Central

    Pu, Shenghong; Nakagome, Kazuyuki; Miura, Akihiko; Iwata, Masaaki; Nagata, Izumi; Kaneko, Koichi

    2016-01-01

    Though depressive symptoms are common in patients with schizophrenia, they are often left untreated and are associated with a high relapse rate, suicidal ideation, increased mortality, reduced social adjustment, and poor quality of life. The present study aims to elucidate the association between depressive symptoms and fronto-temporal activities during a cognitive task in patients with schizophrenia. The fronto-temporal activities of 41 Japanese patients with schizophrenia was evaluated during a verbal fluency task using 52-channel near-infrared spectroscopy (NIRS). Depressive symptoms were assessed using the depression/anxiety component of the Positive and Negative Syndrome Scale (PANSS) five-factor model. The depression/anxiety component of the PANSS five-factor model was negatively correlated with activities of the ventrolateral prefrontal cortex (PFC), right dorsolateral PFC, and left temporal regions. Our findings suggest that reduced fronto-temporal activities on NIRS during a verbal fluency task is related to depressive symptom severity in patients with schizophrenia. PMID:27465466

  10. The Development of Creativity in Preschoolers' Drawings through Task-Oriented Activities

    ERIC Educational Resources Information Center

    Dulama, Maria Eliza; Iovu, Mihai-Bogdan; Vanea, Cornelia

    2011-01-01

    The goal of this paper is to plan working task for preschool children in order to deliver original and creative outputs. The theoretical background of the paper is set in defining creativity as "the capacity to create something new, original, and adequate to reality" (Roco, 2004; Jaoui, 1975; Rosca, 1981; Boden, 1992). The research…

  11. Subjective Task Value in Physical Activity Participation: The Perspective of Hong Kong Schoolchildren

    ERIC Educational Resources Information Center

    Pang, Bonnie; Ha, Amy Sau Ching

    2010-01-01

    Subjective Task Value (STV) is a multidimensional construct of values predominantly used to examine western culture (Eccles et al., 1983); it is influential in motivating individuals to make choices and display long-lasting behaviours. While existing studies were conducted with western populations, the manifestation of value has yet to be…

  12. Decreased Functional Brain Activation in Friedreich Ataxia Using the Simon Effect Task

    ERIC Educational Resources Information Center

    Georgiou-Karistianis, N.; Akhlaghi, H.; Corben, L. A.; Delatycki, M. B.; Storey, E.; Bradshaw, J. L.; Egan, G. F.

    2012-01-01

    The present study applied the Simon effect task to examine the pattern of functional brain reorganization in individuals with Friedreich ataxia (FRDA), using functional magnetic resonance imaging (fMRI). Thirteen individuals with FRDA and 14 age and sex matched controls participated, and were required to respond to either congruent or incongruent…

  13. ECoG Gamma Activity during a Language Task: Differentiating Expressive and Receptive Speech Areas

    ERIC Educational Resources Information Center

    Towle, Vernon L.; Yoon, Hyun-Ah; Castelle, Michael; Edgar, J. Christopher; Biassou, Nadia M.; Frim, David M.; Spire, Jean-Paul; Kohrman, Michael H.

    2008-01-01

    Electrocorticographic (ECoG) spectral patterns obtained during language tasks from 12 epilepsy patients (age: 12-44 years) were analyzed in order to identify and characterize cortical language areas. ECoG from 63 subdural electrodes (500 Hz/channel) chronically implanted over frontal, parietal and temporal lobes were examined. Two language tasks…

  14. Dissociating Linguistic and Task-Related Activity in the Left Inferior Frontal Gyrus

    ERIC Educational Resources Information Center

    Wright, Paul; Randall, Billi; Marslen-Wilson, William D.; Tyler, Lorraine K.

    2011-01-01

    The left inferior frontal gyrus (LIFG) has long been claimed to play a key role in language function. However, there is considerable controversy as to whether regions within LIFG have specific linguistic or domain-general functions. Using fMRI, we contrasted linguistic and task-related effects by presenting simple and morphologically complex words…

  15. Report on the activities of the PSN/NASA Task Group

    NASA Technical Reports Server (NTRS)

    Loria, Alberto; Harrison, James K.

    1988-01-01

    Since July '86 the PSN/NASA Task Group for Tether Flight Demonstrations has been working to find applications of tethers in space, the development of which might be of mutual interest to the two agencies. Seven projects have so far been identified and some more will probably be added. A technical evaluation and a managerial plan have been outlined for each.

  16. Language-related activations in the left prefrontal regions are differentially modulated by age, proficiency, and task demands.

    PubMed

    Tatsuno, Yoshinori; Sakai, Kuniyoshi L

    2005-02-16

    It remains to be elucidated how cortical activations are modulated by factors of age, proficiency, and language task demands when mastering first language (L1) and a second language (L2). Using functional magnetic resonance imaging, we tested subjects aged 13 (the age 13 group) and 19 (the age 19 group), thereby comparing the cortical activations involved in past-tense verb identification with those involved in verb matching. We found that the activation in the dorsal triangular part of the left inferior frontal gyrus (IFG) was lower, corresponding to a higher proficiency in English (L2) in the older subjects, suggesting that the proficiency level plays a major role in the activation of this region during L2 acquisition. Moreover, the lower activation in the triangular and orbital parts of the left IFG (F3t/F3O) for the irregular past tense corresponding to a higher proficiency in L2, together with the nonsignificant activation for the regular past tense when its performance almost reached perfection for age 19, suggests that the modulation of the left F3t/F3O activation reflects language task demands for identifying correct past-tense forms. On the other hand, the left F3t/F3O activation in Japanese (L1) for age 13 was significantly greater than that for age 19, despite the matched performances in L1. These results suggest that the left IFG subserves language-specific functions that are critically required when mastering any language.

  17. Low-rank coal research, Task 5.1. Topical report, April 1986--December 1992

    SciTech Connect

    Not Available

    1993-02-01

    This document is a topical progress report for Low-Rank Coal Research performed April 1986 - December 1992. Control Technology and Coal Preparation Research is described for Flue Gas Cleanup, Waste Management, Regional Energy Policy Program for the Northern Great Plains, and Hot-Gas Cleanup. Advanced Research and Technology Development was conducted on Turbine Combustion Phenomena, Combustion Inorganic Transformation (two sections), Liquefaction Reactivity of Low-Rank Coals, Gasification Ash and Slag Characterization, and Coal Science. Combustion Research is described for Atmospheric Fluidized-Bed Combustion, Beneficiation of Low-Rank Coals, Combustion Characterization of Low-Rank Fuels (completed 10/31/90), Diesel Utilization of Low-Rank Coals (completed 12/31/90), Produce and Characterize HWD (hot-water drying) Fuels for Heat Engine Applications (completed 10/31/90), Nitrous Oxide Emission, and Pressurized Fluidized-Bed Combustion. Liquefaction Research in Low-Rank Coal Direct Liquefaction is discussed. Gasification Research was conducted in Production of Hydrogen and By-Products from Coals and in Sulfur Forms in Coal.

  18. Research on optimal path planning algorithm of task-oriented optical remote sensing satellites

    NASA Astrophysics Data System (ADS)

    Liu, Yunhe; Xu, Shengli; Liu, Fengjing; Yuan, Jingpeng

    2015-08-01

    GEO task-oriented optical remote sensing satellite, is very suitable for long-term continuous monitoring and quick access to imaging. With the development of high resolution optical payload technology and satellite attitude control technology, GEO optical remote sensing satellites will become an important developing trend for aerospace remote sensing satellite in the near future. In the paper, we focused on GEO optical remote sensing satellite plane array stare imaging characteristics and real-time leading mission of earth observation mode, targeted on satisfying needs of the user with the minimum cost of maneuver, and put forward the optimal path planning algorithm centered on transformation from geographic coordinate space to Field of plane, and finally reduced the burden of the control system. In this algorithm, bounded irregular closed area on the ground would be transformed based on coordinate transformation relations in to the reference plane for field of the satellite payload, and then using the branch and bound method to search for feasible solutions, cutting off the non-feasible solution in the solution space based on pruning strategy; and finally trimming some suboptimal feasible solutions based on the optimization index until a feasible solution for the global optimum. Simulation and visualization presentation software testing results verified the feasibility and effectiveness of the strategy.

  19. Task B: Research on stable high-efficiency, large area, amorphous silicon-based solar cells

    SciTech Connect

    Catalano, A.W.; Ayra, R.R.; Bennett, M.S.; Dickson, C.R.; Fieselmann, B.; Goldstein, B.; Morris, J.; Newton, J.L.; O'Dowd, J.G.; Oswald, R.S.; Twesme, E.; Wiedeman, S.; Yang, L. . Thin Film Div.)

    1989-10-01

    This document describes photovoltaic research conducted in four areas: semiconductor materials, high-efficiency cells, nonsemiconductor materials, and submodules. The major focus of semiconductor materials research was on improving the quality of wide-band-gap a-SiC:H alloys and narrow-band-gap a-SiGe:H alloys. Raman spectroscopy suggested that the alloys are inhomogeneous, showing a higher concentration of Ge-Ge bonds than expected from a random mixing model. In high-efficiency device research, silicon-carbon single-junction cells resulted in open-circuit voltages as high as 0.96 V with a higher than 0.6 fill factor. Silicon-germanium cells show far better performance using a p/i-graded interface, an i(a-Si)/i(a-SiGe)-graded interface, and an inverse-graded interface at the i/n junction along with an a-Si n-layer compared with an a-SiGe:H n-layer. In the nonsemiconductor materials research, modeling optical enhancement of long-wavelength light in single-junction cells suggested that several parasitic losses are present in the device structure. In most cases, absorption in the rear contact is the major loss mechanism. In submodule research, the focus was on developing high-efficiency a-Si:H single-junction modules, stable a-Si:H stacked-junction modules, high-efficiency alloy-stacked modules, and advanced laser scribing processes. 74 figs., 13 tabs.

  20. Press CRTT to measure aggressive behavior: the unstandardized use of the competitive reaction time task in aggression research.

    PubMed

    Elson, Malte; Mohseni, M Rohangis; Breuer, Johannes; Scharkow, Michael; Quandt, Thorsten

    2014-06-01

    The competitive reaction time task (CRTT) is the measure of aggressive behavior most commonly used in laboratory research. However, the test has been criticized for issues in standardization because there are many different test procedures and at least 13 variants to calculate a score for aggressive behavior. We compared the different published analyses of the CRTT using data from 3 different studies to scrutinize whether it would yield the same results. The comparisons revealed large differences in significance levels and effect sizes between analysis procedures, suggesting that the unstandardized use and analysis of the CRTT have substantial impacts on the results obtained, as well as their interpretations. Based on the outcome of our comparisons, we provide suggestions on how to address some of the issues associated with the CRTT, as well as a guideline for researchers studying aggressive behavior in the laboratory.

  1. Inhibition of propofol on single neuron and neuronal ensemble activity in prefrontal cortex of rats during working memory task.

    PubMed

    Xu, Xinyu; Tian, Yu; Wang, Guolin; Tian, Xin

    2014-08-15

    Working memory (WM) refers to the temporary storage and manipulation of information necessary for performance of complex cognitive tasks. There is a growing interest in whether and how propofol anesthesia inhibits WM function. The aim of this study is to investigate the possible inhibition mechanism of propofol anesthesia from the view of single neuron and neuronal ensemble activities. Adult SD rats were randomly divided into two groups: propofol group (0.9 mg kg(-1)min(-1), 2h via a tail vein catheter) and control group. All the rats were tested for working memory performances in a Y-maze-rewarded alternation task (a task of delayed non-matched-to-sample) at 24, 48, 72 h after propofol anesthesia, and the behavior results of WM tasks were recorded at the same time. Spatio-temporal trains of action potentials were obtained from the original signals. Single neuron activity was characterized by peri-event time histograms analysis and neuron ensemble activities were characterized by Granger causality to describe the interactions within the neuron ensemble. The results show that: comparing with the control group, the percentage of neurons excited and related to WM was significantly decreased (p<0.01 in 24h, p<0.05 in 48 h); the interactions within neuron ensemble were significantly weakened (p<0.01 in 24h, p<0.05 in 48 h), whereas no significant difference in 72 h (p>0.05), which were consistent with the behavior results. These findings could lead to improved understanding of the mechanism of anesthesia inhibition on WM functions from the view of single neuron activity and neuron ensemble interactions.

  2. Task A: Research in theoretical elementary particle physics at the University of Florida; Annual progress report

    SciTech Connect

    Field, R.D.; Ramond, P.M.; Sikivie, P.; Thorn, C.B.

    1993-11-01

    This is the Annual Progress Report of the theoretical particle theory group at the University of Florida under DoE Grant DE-FG05-86ER40272. At present our group consists of four Full Professors (Field, Ramond, Thorn, Sikivie) and three Assistant Professors (Qiu, Woodard, Kennedy). Dallas Kennedy recently joined our group increasing the Particle Theory faculty to seven. In addition, we have three postdoctoral research associates, an SSC fellow, and eight graduate students. The research of our group covers a broad range of topics in theoretical high energy physics with balance between theory and phenomenology. Included in this report is a summary of the last several years of operation of the group and an outline of our current research program.

  3. Student Off-Task Behavior in Computer-Based Learning in the Philippines: Comparison to Prior Research in the USA

    ERIC Educational Resources Information Center

    Rodrigo, Ma. Mercedes T.; Baker, Ryan S. J. D.; Rossi, Lisa

    2013-01-01

    Background: Off-task behavior can be defined as any behavior that does not involve the learning task or material, or where learning from the material is not the primary goal. One suggested path for understanding how to address off-task behavior is to study classrooms where off-task behavior is less common, particularly in Asia, in order to…

  4. A task control theory of mirror-touch synesthesia.

    PubMed

    Heyes, Cecilia; Catmur, Caroline

    2015-01-01

    Ward and Banissy's illuminating discussion of mirror-touch synesthesia (MTS) encourages research testing two alternatives to Threshold Theory: Their own Self-Other Theory, and "Task Control Theory". MTS may be due to abnormal mirror activity plus a domain-general, rather than a specifically social, impairment in the ability to privilege processing of task-relevant over task-irrelevant information.

  5. Task Engagement: A Turning Point in Foreign Language Development.

    ERIC Educational Resources Information Center

    Platt, Elizabeth J.; Brooks, Frank B.

    2002-01-01

    Uses a sociocultural framework to suggest task engagement as a viable construct in second language learning research. Examines second language learner data to identify task engagement as it emerges, unfolds in dialogic activity, and becomes associated with he transformation of task, self, and group. (Author/VWL)

  6. Event-related oscillations (ERO) during an active discrimination task: Effects of lesions of the nucleus basalis magnocellularis.

    PubMed

    Sanchez-Alavez, Manuel; Ehlers, Cindy L

    2016-05-01

    The cholinergic system in the brain is involved in attentional processes that are engaged for the identification and selection of relevant information in the environment and the formation of new stimulus associations. In the present study we determined the effects of cholinergic lesions of nucleus basalis magnocellularis (NBM) on amplitude and phase characteristics of event related oscillations (EROs) generated in an auditory active discrimination task in rats. Rats were trained to press a lever to begin a series of 1kHz tones and to release the lever upon hearing a 2kHz tone. A time-frequency based representation was used to determine ERO energy and phase synchronization (phase lock index, PLI) across trials, recorded within frontal cortical structures. Lesions in NBM produced by an infusion of a-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) resulted in (1) a reduction of the number of correct behavioral responses in the active discrimination task, (2) an increase in ERO energy in the delta frequency bands, (3) an increase in theta, alpha and beta ERO energy in the N1, P3a and P3b regions of interest (ROI), and (4) an increase in PLI in the theta frequency band in the N1 ROIs. These studies suggest that the NBM cholinergic system is involved in maintaining the synchronization/phase resetting of oscillations in different frequencies in response to the presentation of the target stimuli in an active discrimination task. PMID:25660307

  7. No difference in frontal cortical activity during an executive functioning task after acute doses of aripiprazole and haloperidol

    PubMed Central

    Bolstad, Ingeborg; Andreassen, Ole A.; Groote, Inge R.; Haatveit, Beathe; Server, Andres; Jensen, Jimmy

    2015-01-01

    Background: Aripiprazole is an atypical antipsychotic drug that is characterized by partial dopamine D2 receptor agonism. Its pharmacodynamic profile is proposed to be beneficial in the treatment of cognitive impairment, which is prevalent in psychotic disorders. This study compared brain activation characteristics produced by aripiprazole with that of haloperidol, a typical D2 receptor antagonist, during a task targeting executive functioning. Methods: Healthy participants received an acute oral dose of haloperidol, aripiprazole or placebo before performing an executive functioning task while blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) was carried out. Results: There was a tendency towards reduced performance in the aripiprazole group compared to the two other groups. The image analysis yielded a strong task-related BOLD-fMRI response within each group. An uncorrected between-group analysis showed that aripiprazole challenge resulted in stronger activation in the frontal and temporal gyri and the putamen compared with haloperidol challenge, but after correcting for multiple testing there was no significant group difference. Conclusion: No significant group differences between aripiprazole and haloperidol in frontal cortical activation were obtained when corrected for multiple comparisons. This study is registered in ClinicalTrials.gov (identifier: 2009-016222-14).1 PMID:26074803

  8. Bilateral injection of fasciculin into the amygdala of rats: effects on two avoidance tasks, acetylcholinesterase activity, and cholinergic muscarinic receptors.

    PubMed

    Quillfeldt, J; Raskovsky, S; Dalmaz, C; Dias, M; Huang, C; Netto, C A; Schneider, F; Izquierdo, I; Medina, J H; Silveira, R

    1990-11-01

    These experiments examined the effects of the bilateral injection of fasciculin-2 (FAS), a natural acetylcholinesterase (AChE) inhibitory peptide, into the amygdala of rats on acquisition and retention of two avoidance behaviors. Intraamygdala injection of FAS (150 ng/amygdala) produced a pronounced and long-lasting inhibition of AChE activity: 85% and 74% on day 2 and day 5, respectively. After 48 hr, FAS-treated animals showed no changes in training or test session performance in a step-down inhibitory avoidance task (training-test interval was 24 hr). In a 2-way shuttle avoidance task, intraamygdala FAS slightly reduced retention test performance without modifying training session scores. Two and five days after FAS injections into the amygdala, the density of muscarinic receptor decreased about 50% as measured by the specific bindings of 3H-quinuclidinyl benzilate and 3H-oxotremorine. No alterations were observed in the apparent dissociation constants. On the other hand, the central-type benzodiazepine receptor population of the amygdala remained unchanged, suggesting that FAS microinjection did not produce damage to neuronal components of these nuclei. In conclusion, the results presented have indicated that a clear-cut and long-lasting inhibition of AChE activity in the amygdala is not accompanied by a facilitation of learning and memory of two different avoidance tasks. Compensation of the increased cholinergic activity by a down-regulation of muscarinic receptors could account for these findings.

  9. Qualitative Meta-Analysis on the Hospital Task: Implications for Research

    ERIC Educational Resources Information Center

    Noll, Jennifer; Sharma, Sashi

    2014-01-01

    The "law of large numbers" indicates that as sample size increases, sample statistics become less variable and more closely estimate their corresponding population parameters. Different research studies investigating how people consider sample size when evaluating the reliability of a sample statistic have found a wide range of…

  10. Theoretical high energy physics research at the University of Chicago, task A

    NASA Astrophysics Data System (ADS)

    Rosner, J. L.; Martinec, E. J.; Sachs, R. G.

    1992-04-01

    This report discusses research conducted at the University of Chicago in theoretical high energy physics. Some of the areas included in this report are: cp violation and cabibbo-kobayashi-maskawa matrix; radiative corrections and electroweak observables; heavy quark symmetry; heavy meson spectroscopy; hadronic string theory; composite models of quarks and leptons; and pedagogical effects.

  11. The activation of semantic memory: effects of prime exposure, prime-target relationship, and task demands.

    PubMed

    Bueno, Steve; Frenck-Mestre, Cheryl

    2008-06-01

    Priming facilitation was examined under conditions of brief incremental prime exposures (28, 43, 71, and 199 msec) under masked conditions for two types of lexical relationships (associative-semantic pairs, such as "wolf-fox," and semantic-feature pairs, such as "whale-dolphin") and in two tasks (primed lexical decision and semantic categorization). The results of eight experiments revealed, first, that priming elicits faster response times for semantic-feature pairs. The associative-semantic pairs produced priming only at the longer prime exposures. Second, priming was observed earlier for semantic categorization than for the lexical decision task, in which priming was observed only at the longer stimulus onset asynchronies. Finally, our results allowed us to discredit the congruency hypothesis, according to which priming is due to a common categorical response for the prime and target words. The implications of these results for current theories of semantic priming are discussed.

  12. Jogging improved performance of a behavioral branching task: implications for prefrontal activation.

    PubMed

    Harada, Taeko; Okagawa, Satoru; Kubota, Kisou

    2004-07-01

    We studied the effect of habitual jogging on the performance of a frontal lobe functioning test. Fourteen subjects were divided into a jogging trained group (TG) or a jogging untrained group (NG). The TG jogged for 12 weeks, for 30 min, 2.6 times per week, while the NG did not. We administered a prefrontal branching task (BR) combining a Spatial Delayed-Response Test (DR) and a Go/No-Go Test (GNG). Each test alone and a Simple Reaction Time Test (SR) were given as controls. All tests were given three times at 6 week intervals over 12 weeks in both groups. In the TG, the tests were given two times after termination of the jogging. The maximal oxygen uptake (VO2max) was measured in the TG during the 12 weeks. After 12 weeks, the correct performance rates in the BR task were more improved in the TG than in the NG. The control and reaction time tests were unchanged in both groups. The improved performance in the BR task in the TG decreased after stopping the jogging. The VO2max increased significantly during the 12 weeks of jogging in the TG. Thus, the habitual jogging improved performance in a prefrontal BR.

  13. fMRI brain activation during a delay discounting task in HIV-positive adults with and without cocaine dependence

    PubMed Central

    Meade, Christina S.; Lowen, Steven B.; MacLean, Robert R.; Key, Mary D.; Lukas, Scott E.

    2011-01-01

    Cocaine use is associated with poorer HIV clinical outcomes and may contribute to neurobiological impairments associated with impulsive decision making. This study examined the effect of cocaine dependence on brain activation during a delay discounting task involving choices between smaller immediate rewards and larger delayed ones. Participants were 39 HIV-positive adults on antiretroviral therapy who had current cocaine dependence (“active,” n=15), past cocaine dependence (“recovered,” n=13), or no lifetime substance dependence (“naïve,” n=11). Based on responses on a traditional delay discounting task, three types of choices were individualized for presentation during fMRI scanning: hard (similarly valued), easy (disparately valued), and no (single option). Active participants had significantly smaller increases in activation than naïve participants during hard versus easy choices bilaterally in the precentral gyrus and anterior cingulate cortex and in the right frontal pole (including dorsolateral, ventrolateral, and orbitofrontal cortex). During hard and easy choices relative to no choices, active participants had smaller increases in activation compared to naïve participants in frontoparietal cortical regions. These deficits in the executive network during delay discounting choices may contribute to impulsive decision making among HIV-positive cocaine users, with implications for risk behaviors associated with disease transmission and progression. PMID:21546221

  14. Evaluating Teaching and Research Activities--Finding the Right Balance.

    ERIC Educational Resources Information Center

    Vidal, Javier; Mora, Jose-Gines

    2003-01-01

    Analyzes on a national, regional, and institutional level the evaluation systems used to assess teaching and research activities at Spanish universities. Also examines ways in which evaluation systems orient to promote research activities to the detriment of teaching activities. (SWM)

  15. Drug polyconsumption is associated with increased synchronization of brain electrical-activity at rest and in a counting task.

    PubMed

    Coullaut-Valera, R; Arbaiza, I; Bajo, R; Arrúe, R; López, M E; Coullaut-Valera, J; Correas, A; López-Sanz, D; Maestu, F; Papo, D

    2014-02-01

    Drug abusers typically consume not just one but several types of drugs, starting from alcohol and marijuana consumption, and then dramatically lapsing into addiction to harder drugs, such as cocaine, heroin, or amphetamine. The brain of drug abusers presents various structural and neurophysiological abnormalities, some of which may predate drug consumption onset. However, how these changes translate into modifications in functional brain connectivity is still poorly understood. To characterize functional connectivity patterns, we recorded Electroencephalogram (EEG) activity from 21 detoxified drug abusers and 20 age-matched control subjects performing a simple counting task and at rest activity. To evaluate the cortical brain connectivity network we applied the Synchronization Likelihood algorithm. The results showed that drug abusers had higher synchronization levels at low frequencies, mainly in the θ band (4-8 Hz) between frontal and posterior cortical regions. During the counting task, patients showed increased synchronization in the β (14-35 Hz), and γ (35-45 Hz) frequency bands, in fronto-posterior and interhemispheric temporal regions. Taken together 'slow-down' at rest and task-related 'over-exertion' could indicate that the brain of drug abusers is suffering from a premature form of ageing. Future studies will clarify whether this condition can be reversed following prolonged periods of abstinence.

  16. Language Research Center's Computerized Test System (LRC-CTS) - Video-formatted tasks for comparative primate research

    NASA Technical Reports Server (NTRS)

    Rumbaugh, Duane M.; Washburn, David A.; Savage-Rumbaugh, E. S.; Hopkins, William D.; Richardson, W. K.

    1991-01-01

    Automation of a computerized test system for comparative primate research is shown to improve the results of learning in standard paradigms. A mediational paradigm is used to determine the degree to which criterion in the learning-set testing reflects stimulus-response associative or mediational learning. Rhesus monkeys are shown to exhibit positive transfer as the criterion levels are shifted upwards, and the effectiveness of the computerized testing system is confirmed.

  17. An overview of Japanese CELSS research activities

    NASA Technical Reports Server (NTRS)

    Nitta, Keiji

    1987-01-01

    Development of Controlled Ecological Life Support System (CELSS) technology is inevitable for future long duration stays of human beings in space, for lunar base construction and for manned Mars flight programs. CELSS functions can be divided into 2 categories, Environmental Control and Material Recycling. Temperature, humidity, total atmospheric pressure and partial pressure of oxygen and carbon dioxide, necessary for all living things, are to be controlled by the environment control function. This function can be performed by technologies already developed and used as the Environment Control Life Support System (ECLSS) of Space Shuttle and Space Station. As for material recycling, matured technologies have not yet been established for fully satisfying the specific metabolic requirements of each living thing including human beings. Therefore, research activities for establishing CELSS technology should be focused on material recycling technologies using biological systems such as plants and animals and physico-chemical systems, for example, a gas recycling system, a water purifying and recycling system and a waste management system. Japanese research activities were conducted and will be continued accordingly.

  18. Task 21 - Development of Systems Engineering Applications for Decontamination and Decommissioning Activities

    SciTech Connect

    Erickson, T.A.

    1998-11-01

    The objectives of this task are to: Develop a model (paper) to estimate the cost and waste generation of cleanup within the Environmental Management (EM) complex; Identify technologies applicable to decontamination and decommissioning (D and D) operations within the EM complex; Develop a database of facility information as linked to project baseline summaries (PBSs). The above objectives are carried out through the following four subtasks: Subtask 1--D and D Model Development, Subtask 2--Technology List; Subtask 3--Facility Database, and Subtask 4--Incorporation into a User Model.

  19. Materials processing in space program tasks

    NASA Technical Reports Server (NTRS)

    Mckannan, E. C. (Editor)

    1978-01-01

    A list of active research tasks as of the end of 1978 of the Materials Processing in Space Program of the Office of Space and Terrestrial Applications, involving several NASA Centers and other organizations is reported. An overview of the program scope for managers and scientists in industry, university and government communities is provided. The program, its history, strategy and overall goal; the organizational structures and people involved; and each research task are described. Tasks are categorized by ground based research according to four process areas. Cross references to the performing organizations and principal investigators are provided.

  20. Electromechanically active polymer transducers: research in Europe

    NASA Astrophysics Data System (ADS)

    Carpi, Federico; Graz, Ingrid; Jager, Edwin; Ladegaard Skov, Anne; Vidal, Frédéric

    2013-10-01

    Smart materials and structures based on electromechanically active polymers (EAPs) represent a fast growing and stimulating field of research and development. EAPs are materials capable of changing dimensions and/or shape in response to suitable electrical stimuli. They are commonly classified in two major families: ionic EAPs (activated by an electrically induced transport of ions and/or solvent) and electronic EAPs (activated by electrostatic forces). These polymers show interesting properties, such as sizable active strains and/or stresses in response to electrical driving, high mechanical flexibility, low density, structural simplicity, ease of processing and scalability, no acoustic noise and, in most cases, low costs. Since many of these characteristics can also describe natural muscle tissues from an engineering standpoint, it is not surprising that EAP transducers are sometimes also referred to as 'muscle-like smart materials' or 'artificial muscles'. They are used not only to generate motion, but also to sense or harvest energy from it. In particular, EAP electromechanical transducers are studied for applications that can benefit from their 'biomimetic' characteristics, with possible usages from the micro- to the macro-scale, spanning several disciplines, such as mechatronics, robotics, automation, biotechnology and biomedical engineering, haptics, fluidics, optics and acoustics. Currently, the EAP field is just undergoing its initial transition from academic research into commercialization, with companies starting to invest in this technology and the first products appearing on the market. This focus issue is intentionally aimed at gathering contributions from the most influential European groups working in the EAP field. In fact, today Europe hosts the broadest EAP community worldwide. The rapid expansion of the EAP field in Europe, where it historically has strong roots, has stimulated the creation of the 'European Scientific Network for Artificial

  1. Impaired regional hemodynamic response in schizophrenia during multiple prefrontal activation tasks: a two-channel near-infrared spectroscopy study.

    PubMed

    Ikezawa, Koji; Iwase, Masao; Ishii, Ryouhei; Azechi, Michiyo; Canuet, Leonides; Ohi, Kazutaka; Yasuda, Yuka; Iike, Naomi; Kurimoto, Ryu; Takahashi, Hidetoshi; Nakahachi, Takayuki; Sekiyama, Ryuji; Yoshida, Tetsuhiko; Kazui, Hiroaki; Hashimoto, Ryota; Takeda, Masatoshi

    2009-03-01

    In schizophrenia, dysfunction of the prefrontal cortex (PFC), regarded as a core feature of the disease, has been investigated by different neuroimaging methods. Near infrared spectroscopy (NIRS), a novel neurophysiological method, is being increasingly used in the investigation of frontal dysfunction in schizophrenia. However, NIRS measurements during multiple frontal activation tasks have been rarely reported. The purpose of this study was to compare hemodynamic changes in the PFC between patients with schizophrenia and healthy controls during four different types of frontal lobe tasks using a 2-channel NIRS system. Thirty patients with schizophrenia and thirty age- and gender-matched healthy controls were enrolled in this study. In both groups, changes in oxygenated hemoglobin concentration (Delta[oxyHb]) at the bilateral forehead were measured during Verbal fluency test letter version (VFT-letter), VFT category version, Tower of Hanoi (TOH), the Sternberg and Stroop tasks. Regarding Delta[oxyHb] in PFC, a diagnosis group effect was found for VFT-letter and TOH. Significant negative correlation was found between left Delta[oxyHb] during TOH and negative and cognitive symptom scores in schizophrenia patients. Right Delta[oxyHb] during TOH also showed significant negative correlation with cognitive symptoms scores. No significant correlation between Delta[oxyHb] and clinical characteristics were observed during VFT-letter. These findings suggest that among a battery of frontal lobe tasks administered to schizophrenia patients, VFT-letter and TOH are more sensitive to detect PFC activation, as indicated by Delta[oxyHb] using a 2-channel NIRS. Taken together, these findings and those of previous neuroimaging studies suggest that VFT-letter and TOH might represent possible candidate physiological markers of prefrontal dysfunction in schizophrenia, though extensive testing in clinical settings will be necessary. PMID:19157786

  2. Positive Activities: Qualitative Research with Parents. Solutions Research. Research Report. DCSF-RR142

    ERIC Educational Resources Information Center

    Department for Children, Schools and Families, 2009

    2009-01-01

    This research was commissioned by COI and DCSF to understand in depth, the barriers, motivators and messages for parents to encourage participation in positive activities for young people. Within this the research was designed to understand the level of influence of parents in whether a young person participates/what a young person might…

  3. Feasibility of developing a portable driver performance data acquisition system for human factors research: Technical tasks. Volume 1

    SciTech Connect

    Carter, R.J.; Barickman, F.S.; Spelt, P.F.; Schmoyer, R.L.; Kirkpatrick, J.R.

    1998-01-01

    A two-phase, multi-year research program entitled ``development of a portable driver performance data acquisition system for human factors research`` was recently completed. The primary objective of the project was to develop a portable data acquisition system for crash avoidance research (DASCAR) that will allow drive performance data to be collected using a large variety of vehicle types and that would be capable of being installed on a given vehicle type within a relatively short-time frame. During phase 1 a feasibility study for designing and fabricating DASCAR was conducted. In phase 2 of the research DASCAR was actually developed and validated. This technical memorandum documents the results from the feasibility study. It is subdivided into three volumes. Volume one (this report) addresses the last five items in the phase 1 research and the first issue in the second phase of the project. Volumes two and three present the related appendices, and the design specifications developed for DASCAR respectively. The six tasks were oriented toward: identifying parameters and measures; identifying analysis tools and methods; identifying measurement techniques and state-of-the-art hardware and software; developing design requirements and specifications; determining the cost of one or more copies of the proposed data acquisition system; and designing a development plan and constructing DASCAR. This report also covers: the background to the program; the requirements for the project; micro camera testing; heat load calculations for the DASCAR instrumentation package in automobile trunks; phase 2 of the research; the DASCAR hardware and software delivered to the National Highway Traffic Safety Administration; and crash avoidance problems that can be addressed by DASCAR.

  4. ASPEN PLUS modeling of the SRC-I Demonstration Plant. Task 19: modeling support activities report

    SciTech Connect

    Not Available

    1984-09-28

    The APCI version of ASPEN PLUS was maintained and enhanced in order to support the requirements of the simulation effort described in the earlier tasks. The support effort is conveniently divided into systems support and technical support in the areas of flowsheeting and thermophysical properties. Systems support required installation of the fourth release of ASPEN PLUS, installation of AspenTech's updates to correct program errors, and several general maintenance tasks unique to the APCI version of ASPEN PLUS. Technical support in the area of flowsheeting consisted of the organization of training courses, consultation in solving simulation problems, and identifying and resolving problems resulting from bugs in ASPEN PLUS. Thermodynamic technical support consisted of developing a few new models, implementing the coal-fluid thermophysical models into ASPEN PLUS, providing convenient access to the physical properties through INSERTs, and consultation to resolve simulation problems resulting from the nonideality of the properties. All software enhancements to ASPEN PLUS have been described and delivered so that APCI's version of the program may be duplicated and maintained at other sites. 16 references.

  5. Automatic activation of phonological information in reading: evidence from the semantic relatedness decision task.

    PubMed

    Luo, C R; Johnson, R A; Gallo, D A

    1998-07-01

    A semantic relatedness decision task was used to investigate whether phonological recording occurs automatically and whether it mediates lexical access in visual word recognition and reading. In this task, subjects read a pair of words and decided whether they were related or unrelated in meaning. In Experiment 1, unrelated word-homophone pairs (e.g., LION-BARE) and their visual controls (e.g., LION-BEAN) as well as related word pairs (e.g., FISH-NET) were presented. Homophone pairs were more likely to be judged as related or more slowly rejected as unrelated than their control pairs, suggesting phonological access of word meanings. In Experiment 2, word-pseudohomophone pairs (e.g., TABLE-CHARE) and their visual controls (e.g., TABLE-CHARK) as well as related and unrelated word pairs were presented. Pseudohomophone pairs were more likely to be judged as related or more slowly rejected as unrelated than their control pairs, again suggesting automatic phonological recording in reading. PMID:9701974

  6. [Present situation and research task on the assessment of psychological effects caused by low-frequency noise].

    PubMed

    Takahashi, Yukio

    2013-01-01

    Wind power generation is one of the good solutions to ensuring a clean and sustainable energy source. In recent years, therefore, many facilities for wind power generation have been constructed in Japan. In contrast to its advantage, however, residents in some areas near a wind power generation site have complained that their well-being has been disturbed by noise from wind turbines. Wind turbines generate low-frequency noise, which can lead to adverse psychological effects such as annoyance. In Japan, the method of assessing appropriately the adverse effects caused by low-frequency noise has not been established. In this article, the characteristics and effects of low-frequency noise are outlined, and the present situation and research task on the assessment of psychological effects of low-frequency noise from wind turbines are presented.

  7. Active ocular vergence improves postural control in elderly as close viewing distance with or without a single cognitive task.

    PubMed

    Matheron, Eric; Yang, Qing; Delpit-Baraut, Vincent; Dailly, Olivier; Kapoula, Zoï

    2016-01-01

    Performance of the vestibular, visual, and somatosensory systems decreases with age, reducing the capacity of postural control, and increasing the risk of falling. The purpose of this study is to measure the effects of vision, active vergence eye movements, viewing distance/vergence angle and a simple cognitive task on postural control during an upright stance, in completely autonomous elderly individuals. Participated in the study, 23 elderly subjects (73.4 ± 6.8 years) who were enrolled in a center dedicated to the prevention of falling. Their body oscillations were measured with the DynaPort(®) device, with three accelerometers, placed at the lumbosacral level, near the center of mass. The conditions were the following: eyes open fixating on LED at 20 cm or 150 cm (vergence angle 17.0° and 2.3° respectively) with or without additional cognitive tasks (counting down from one hundred), performing active vergence by alternating the fixation between the far and the near LED (convergence and divergence), eyes closed after having fixated the far LED. The results showed that the postural stability significantly decreased when fixating on the LED at a far distance (weak convergence angle) with or without cognitive tasks; active convergence-divergence between the LEDs improved the postural stability while eye closure decreased it. The privilege of proximity (with increased convergence at near), previously established with foot posturography, is shown here to be valid for accelerometry with the center of mass in elderly. Another major result is the beneficial contribution of active vergence eye movements to better postural stability. The results bring new perspectives for the role of eye movement training to preserve postural control and autonomy in elderly.

  8. Model transparency and validation: a report of the ISPOR-SMDM Modeling Good Research Practices Task Force-7.

    PubMed

    Eddy, David M; Hollingworth, William; Caro, J Jaime; Tsevat, Joel; McDonald, Kathryn M; Wong, John B

    2012-01-01

    Trust and confidence are critical to the success of health care models. There are two main methods for achieving this: transparency (people can see how the model is built) and validation (how well it reproduces reality). This report describes recommendations for achieving transparency and validation, developed by a task force appointed by the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) and the Society for Medical Decision Making (SMDM). Recommendations were developed iteratively by the authors. A nontechnical description should be made available to anyone-including model type and intended applications; funding sources; structure; inputs, outputs, other components that determine function, and their relationships; data sources; validation methods and results; and limitations. Technical documentation, written in sufficient detail to enable a reader with necessary expertise to evaluate the model and potentially reproduce it, should be made available openly or under agreements that protect intellectual property, at the discretion of the modelers. Validation involves face validity (wherein experts evaluate model structure, data sources, assumptions, and results), verification or internal validity (check accuracy of coding), cross validity (comparison of results with other models analyzing same problem), external validity (comparing model results to real-world results), and predictive validity (comparing model results with prospectively observed events). The last two are the strongest form of validation. Each section of this paper contains a number of recommendations that were iterated among the authors, as well as the wider modeling task force jointly set up by the International Society for Pharmacoeconomics and Outcomes Research and the Society for Medical Decision Making. PMID:22990088

  9. Similar ventral occipito-temporal cortex activations in literate and illiterate adults during the Chinese character matching task: an fMRI study.

    PubMed

    Qi, Geqi; Li, Xiujun; Yan, Tianyi; Wang, Bin; Yang, Jiajia; Wu, Jinglong; Guo, Qiyong

    2014-04-30

    Visual word expertise is typically associated with enhanced ventral occipito-temporal (vOT) cortex activation in response to written words. Previous study utilized a passive viewing task and found that vOT response to written words was significantly stronger in literate compared to the illiterate subjects. However, recent neuroimaging findings have suggested that vOT response properties are highly dependent upon the task demand. Thus, it is unknown whether literate adults would show stronger vOT response to written words compared to illiterate adults during other cognitive tasks, such as perceptual matching. We addressed this issue by comparing vOT activations between literate and illiterate adults during a Chinese character and simple figure matching task. Unlike passive viewing, a perceptual matching task requires active shape comparison, therefore minimizing automatic word processing bias. We found that although the literate group performed better at Chinese character matching task, the two subject groups showed similar strong vOT responses during this task. Overall, the findings indicate that the vOT response to written words is not affected by expertise during a perceptual matching task, suggesting that the association between visual word expertise and vOT response may depend on the task demand. PMID:24582905

  10. What automaticity deficit? Activation of lexical information by readers with dyslexia in a rapid automatized naming Stroop-switch task.

    PubMed

    Jones, Manon W; Snowling, Margaret J; Moll, Kristina

    2016-03-01

    Reading fluency is often predicted by rapid automatized naming (RAN) speed, which as the name implies, measures the automaticity with which familiar stimuli (e.g., letters) can be retrieved and named. Readers with dyslexia are considered to have less "automatized" access to lexical information, reflected in longer RAN times compared with nondyslexic readers. We combined the RAN task with a Stroop-switch manipulation to test the automaticity of dyslexic and nondyslexic readers' lexical access directly within a fluency task. Participants named letters in 10 × 4 arrays while eye movements and speech responses were recorded. Upon fixation, specific letter font colors changed from black to a different color, whereupon the participant was required to rapidly switch from naming the letter to naming the letter color. We could therefore measure reading group differences on "automatic" lexical processing, insofar as it was task-irrelevant. Readers with dyslexia showed obligatory lexical processing and a timeline for recognition that was overall similar to typical readers, but a delay emerged in the output (naming) phase. Further delay was caused by visual-orthographic competition between neighboring stimuli. Our findings outline the specific processes involved when researchers speak of "impaired automaticity" in dyslexic readers' fluency, and are discussed in the context of the broader literature in this field. PMID:26414305

  11. Atypical subtrochanteric and diaphyseal femoral fractures: report of a task force of the American Society for Bone and Mineral Research.

    PubMed

    Shane, Elizabeth; Burr, David; Ebeling, Peter R; Abrahamsen, Bo; Adler, Robert A; Brown, Thomas D; Cheung, Angela M; Cosman, Felicia; Curtis, Jeffrey R; Dell, Richard; Dempster, David; Einhorn, Thomas A; Genant, Harry K; Geusens, Piet; Klaushofer, Klaus; Koval, Kenneth; Lane, Joseph M; McKiernan, Fergus; McKinney, Ross; Ng, Alvin; Nieves, Jeri; O'Keefe, Regis; Papapoulos, Socrates; Sen, Howe Tet; van der Meulen, Marjolein C H; Weinstein, Robert S; Whyte, Michael

    2010-11-01

    Reports linking long-term use of bisphosphonates (BPs) with atypical fractures of the femur led the leadership of the American Society for Bone and Mineral Research (ASBMR) to appoint a task force to address key questions related to this problem. A multidisciplinary expert group reviewed pertinent published reports concerning atypical femur fractures, as well as preclinical studies that could provide insight into their pathogenesis. A case definition was developed so that subsequent studies report on the same condition. The task force defined major and minor features of complete and incomplete atypical femoral fractures and recommends that all major features, including their location in the subtrochanteric region and femoral shaft, transverse or short oblique orientation, minimal or no associated trauma, a medial spike when the fracture is complete, and absence of comminution, be present to designate a femoral fracture as atypical. Minor features include their association with cortical thickening, a periosteal reaction of the lateral cortex, prodromal pain, bilaterality, delayed healing, comorbid conditions, and concomitant drug exposures, including BPs, other antiresorptive agents, glucocorticoids, and proton pump inhibitors. Preclinical data evaluating the effects of BPs on collagen cross-linking and maturation, accumulation of microdamage and advanced glycation end products, mineralization, remodeling, vascularity, and angiogenesis lend biologic plausibility to a potential association with long-term BP use. Based on published and unpublished data and the widespread use of BPs, the incidence of atypical femoral fractures associated with BP therapy for osteoporosis appears to be very low, particularly compared with the number of vertebral, hip, and other fractures that are prevented by BPs. Moreover, a causal association between BPs and atypical fractures has not been established. However, recent observations suggest that the risk rises with increasing duration of

  12. Heliobiology, its development, successes and tasks. [solar activity effects on life on earth

    NASA Technical Reports Server (NTRS)

    Platonova, A. T.

    1974-01-01

    Heliobiology studies the influence of changes in solar activity on life. Considered are the influence of periodic solar activity on the development and growth of epidemics, mortality from various diseases, the functional activity of the nervous system, the development of psychic disturbances, the details of the development of microorganisms and many other phenomena in the living world.

  13. Linking neuroscientific research on decision making to the educational context of novice students assigned to a multiple-choice scientific task involving common misconceptions about electrical circuits.

    PubMed

    Potvin, Patrice; Turmel, Elaine; Masson, Steve

    2014-01-01

    Functional magnetic resonance imaging was used to identify the brain-based mechanisms of uncertainty and certainty associated with answers to multiple-choice questions involving common misconceptions about electric circuits. Twenty-two scientifically novice participants (humanities and arts college students) were asked, in an fMRI study, whether or not they thought the light bulbs in images presenting electric circuits were lighted up correctly, and if they were certain or uncertain of their answers. When participants reported that they were unsure of their responses, analyses revealed significant activations in brain areas typically involved in uncertainty (anterior cingulate cortex, anterior insula cortex, and superior/dorsomedial frontal cortex) and in the left middle/superior temporal lobe. Certainty was associated with large bilateral activations in the occipital and parietal regions usually involved in visuospatial processing. Correct-and-certain answers were associated with activations that suggest a stronger mobilization of visual attention resources when compared to incorrect-and-certain answers. These findings provide insights into brain-based mechanisms of uncertainty that are activated when common misconceptions, identified as such by science education research literature, interfere in decision making in a school-like task. We also discuss the implications of these results from an educational perspective. PMID:24478680

  14. A Social Validation Assessment of Cooperative versus Individual Task Engagement of Persons with Multiple Disabilities. Research Report

    ERIC Educational Resources Information Center

    Lancioni, Giulio E; O'Reilly, Mark F.; Singh, Nirbhay N.; Pidala, Sara; Piazzolla, Giorgia; Oliva, Doretta; Groeneweg, Jop

    2006-01-01

    One major objective of programs for persons with severe or profound intellectual and multiple disabilities is to teach these persons occupational and vocational tasks and to enable them to carry out these tasks independently (Davis, Brady, Williams, & Burta, 1992; Lancioni et al., 1991; Steed & Lutzker, 1997). The performance of such tasks has…

  15. Optogenetic silencing of locus coeruleus activity in mice impairs cognitive flexibility in an attentional set-shifting task

    PubMed Central

    Janitzky, Kathrin; Lippert, Michael T.; Engelhorn, Achim; Tegtmeier, Jennifer; Goldschmidt, Jürgen; Heinze, Hans-Jochen; Ohl, Frank W.

    2015-01-01

    The locus coeruleus (LC) is the sole source of noradrenergic projections to the cortex and essential for attention-dependent cognitive processes. In this study we used unilateral optogenetic silencing of the LC in an attentional set-shifting task (ASST) to evaluate the influence of the LC on prefrontal cortex-dependent functions in mice. We expressed the halorhodopsin eNpHR 3.0 to reversibly silence LC activity during task performance, and found that silencing selectively impaired learning of those parts of the ASST that most strongly rely on cognitive flexibility. In particular, extra-dimensional set-shifting (EDS) and reversal learning was impaired, suggesting an involvement of the medial prefrontal cortex (mPFC) and the orbitofrontal cortex. In contrast, those parts of the task that are less dependent on cognitive flexibility, i.e., compound discrimination (CD) and the intra-dimensional shifts (IDS) were not affected. Furthermore, attentional set formation was unaffected by LC silencing. Our results therefore suggest a modulatory influence of the LC on cognitive flexibility, mediated by different frontal networks. PMID:26582980

  16. The effect of number of kanji radical companions in character activation with a multi-radical-display task.

    PubMed

    Saito, Hirofumi; Yamazaki, Osamu; Masuda, Hisashi

    2002-01-01

    The majority of Japanese complex kanji consist of two subword units (radicals), and each radical is differentiated according to its combinability. Radical-type frequency is defined as the number of radical companions (NC) functioning as the number of characters containing that radical. The current study is intended to address the question of whether the NC plays a role in kanji character activation under a multi-radical-display (MRD) instead of a tachistoscopic display. An MRD task was used in which the NC was manipulated and the frequency of use of the whole characters was matched on average across the experimental conditions. Participants were divided into two groups (good knowledge vs poor knowledge) according to the score of a kanji completion task. The participants' task was to select an appropriate combination of radicals to compose a legitimate character under the MRD condition. The poor-knowledge group yielded relatively more errors than did the good-knowledge group in the low-NC condition, whereas the good-knowledge group yielded more errors in the high-NC condition than in the low-NC condition. These results demonstrate the different influences of NC as metaknowledge (tacit knowledge of radical productivity) in both good and poor readers. PMID:12081417

  17. Language-specific cortical activation patterns for verbal fluency tasks in Japanese as assessed by multichannel functional near-infrared spectroscopy.

    PubMed

    Dan, Haruka; Dan, Ippeita; Sano, Toshifumi; Kyutoku, Yasushi; Oguro, Keiji; Yokota, Hidenori; Tsuzuki, Daisuke; Watanabe, Eiju

    2013-08-01

    In Japan, verbal fluency tasks are commonly utilized as a standard paradigm for neuropsychological testing of cognitive and linguistic abilities. The Japanese "letter fluency task" is a mora/letter fluency task based on the phonological and orthographical characteristics of the Japanese language. Whether there are similar activation patterns across languages or a Japanese-specific mora/letter fluency pattern is not certain. We investigated the neural correlates of overt mora/letter and category fluency tasks in healthy Japanese. The category fluency task activated the bilateral fronto-temporal language-related regions with left-superior lateralization, while the mora/letter fluency task led to wider activation including the inferior parietal regions (left and right supramarginal gyrus). Specific bilateral supramarginal activation during the mora/letter fluency task in Japanese was distinct from that of similar letter fluency tasks in syllable-alphabet-based languages: this might be due to the requirement of additional phonological processing and working memory, or due to increased cognitive load in general.

  18. Hybrid Tasks: Promoting Statistical Thinking and Critical Thinking through the Same Mathematical Activities

    ERIC Educational Resources Information Center

    Aizikovitsh-Udi, Einav; Clarke, David; Kuntze, Sebastian

    2014-01-01

    Even though statistical thinking and critical thinking appear to have strong links from a theoretical point of view, empirical research into the intersections and potential interrelatedness of these aspects of competence is scarce. Our research suggests that thinking skills in both areas may be interdependent. Given this interconnection, it should…

  19. Increase or Decrease of fMRI Activity in Adult Attention Deficit/ Hyperactivity Disorder: Does It Depend on Task Difficulty?

    PubMed Central

    Merz, Christian J.; Dresler, Thomas; Heupel, Julia; Reichert, Susanne; Jacob, Christian P.; Deckert, Jürgen; Herrmann, Martin J.

    2016-01-01

    Background: Attention deficit/hyperactivity disorder has been shown to affect working memory, and fMRI studies in children and adolescents with attention deficit/hyperactivity disorder report hypoactivation in task-related attentional networks. However, studies with adult attention deficit/hyperactivity disorder patients addressing this issue as well as the effects of clinically valid methylphenidate treatment are scarce. This study contributes to closing this gap. Methods: Thirty-five adult patients were randomized to 6 weeks of double-blind placebo or methylphenidate treatment. Patients completed an fMRI n-back working memory task both before and after the assigned treatment, and matched healthy controls were tested and compared to the untreated patients. Results: There were no whole-brain differences between any of the groups. However, when specified regions of interest were investigated, the patient group showed enhanced BOLD responses in dorsal and ventral areas before treatment. This increase was correlated with performance across all participants and with attention deficit/hyperactivity disorder symptoms in the patient group. Furthermore, we found an effect of treatment in the right superior frontal gyrus, with methylphenidate-treated patients exhibiting increased activation, which was absent in the placebo-treated patients. Conclusions: Our results indicate distinct activation differences between untreated adult attention deficit/hyperactivity disorder patients and matched healthy controls during a working memory task. These differences might reflect compensatory efforts by the patients, who are performing at the same level as the healthy controls. We furthermore found a positive effect of methylphenidate on the activation of a frontal region of interest. These observations contribute to a more thorough understanding of adult attention deficit/hyperactivity disorder and provide impulses for the evaluation of therapy-related changes. PMID:27207920

  20. Bursts of beta oscillation differentiate postperformance activity in the striatum and motor cortex of monkeys performing movement tasks

    PubMed Central

    Feingold, Joseph; Gibson, Daniel J.; DePasquale, Brian; Graybiel, Ann M.

    2015-01-01

    Studies of neural oscillations in the beta band (13–30 Hz) have demonstrated modulations in beta-band power associated with sensory and motor events on time scales of 1 s or more, and have shown that these are exaggerated in Parkinson’s disease. However, even early reports of beta activity noted extremely fleeting episodes of beta-band oscillation lasting <150 ms. Because the interpretation of possible functions for beta-band oscillations depends strongly on the time scale over which they occur, and because of these oscillations’ potential importance in Parkinson’s disease and related disorders, we analyzed in detail the distributions of duration and power for beta-band activity in a large dataset recorded in the striatum and motor-premotor cortex of macaque monkeys performing reaching tasks. Both regions exhibited typical beta-band suppression during movement and postmovement rebounds of up to 3 s as viewed in data averaged across trials, but single-trial analysis showed that most beta oscillations occurred in brief bursts, commonly 90–115 ms long. In the motor cortex, the burst probabilities peaked following the last movement, but in the striatum, the burst probabilities peaked at task end, after reward, and continued through the postperformance period. Thus, what appear to be extended periods of postperformance beta-band synchronization reflect primarily the modulated densities of short bursts of synchrony occurring in region-specific and task-time-specific patterns. We suggest that these short-time-scale events likely underlie the functions of most beta-band activity, so that prolongation of these beta episodes, as observed in Parkinson’s disease, could produce deleterious network-level signaling. PMID:26460033

  1. Task-related oxygen uptake and symptoms during activities of daily life in CHF patients and healthy subjects.

    PubMed

    Spruit, Martijn A; Wouters, Emiel F M; Eterman, Rose-Mieke A; Meijer, Kenneth; Wagers, Scott S; Stakenborg, Koen H P; Uszko-Lencer, Nicole H M K

    2011-08-01

    Patients with chronic heart failure (CHF) have a significantly lower peak aerobic capacity compared to healthy subjects, and, may therefore experience more inconvenience during the performance of domestic activities of daily life (ADLs). To date, the extent to which task-related oxygen uptake, heart rate, ventilation and symptoms during the performance of ADLs in CHF patients is different than in healthy subjects remains uncertain. General demographics, pulmonary function, body composition and peak aerobic capacity were assessed in 23 CHF outpatients and 20 healthy peers. In addition, the metabolic requirement of five simple self-paced domestic ADLs was assessed using a mobile oxycon. Task-related oxygen uptake (ml/min) was similar or lower in CHF patients compared to healthy subjects. In contrast, patients with CHF performing ADLs consumed oxygen at a higher proportion of their peak aerobic capacity than healthy subjects (p < 0.05). For example, getting dressed resulted in a mean task-related oxygen uptake of 49% of peak aerobic capacity, while sweeping the floor resulted in a mean task-related oxygen uptake of 52% of peak aerobic capacity, accompanied by significantly higher Borg symptom scores for dyspnea and fatigue (p < 0.05). Patients with CHF experience use a higher proportion of their peak aerobic capacity, peak ventilation and peak heart rate during the performance of simple self-paced domestic ADL than their healthy peers. These findings represent a necessary step in improving our understanding of improving what troubles patients the most-not being able to do the things that they could when they were healthy.

  2. Towards quantification of blood-flow changes during cognitive task activation using perfusion-based fMRI.

    PubMed

    Mildner, Toralf; Zysset, Stefan; Trampel, Robert; Driesel, Wolfgang; Möller, Harald E

    2005-10-01

    Multi-slice perfusion-based functional magnetic resonance imaging (p-fMRI) is demonstrated with a color-word Stroop task as an established cognitive paradigm. Continuous arterial spin labeling (CASL) of the blood in the left common carotid artery was applied for all repetitions of the functional run in a quasi-continuous fashion, i.e., it was interrupted only during image acquisition. For comparison, blood oxygen level dependent (BOLD) contrast was detected using conventional gradient-recalled echo (GE) echo planar imaging (EPI). Positive activations in BOLD imaging appeared in p-fMRI as negative signal changes corresponding to an enhanced transport of inverted water spins into the region of interest, i.e., increased cerebral blood flow (CBF). Regional differences between the localization of activations and the sensitivity of p-fMRI and BOLD-fMRI were observed as, for example, in the inferior frontal sulcus and in the intraparietal sulcus. Quantification of CBF changes during cognitive task activation was performed on a multi-subject basis and yielded CBF increases of the order of 20-30%.

  3. A preliminary study of functional brain activation among marijuana users during performance of a virtual water maze task.

    PubMed

    Sneider, Jennifer Tropp; Gruber, Staci A; Rogowska, Jadwiga; Silveri, Marisa M; Yurgelun-Todd, Deborah A

    2013-01-01

    Numerous studies have reported neurocognitive impairments associated with chronic marijuana use. Given that the hippocampus contains a high density of cannabinoid receptors, hippocampal-mediated cognitive functions, including visuospatial memory, may have increased vulnerability to chronic marijuana use. Thus, the current study examined brain activation during the performance of a virtual analogue of the classic Morris water maze task in 10 chronic marijuana (MJ) users compared to 18 non-using (NU) comparison subjects. Imaging data were acquired using blood oxygen-level dependent (BOLD) functional MRI at 3.0 Tesla during retrieval (hidden platform) and motor control (visible platform) conditions. While task performance on learning trials was similar between groups, MJ users demonstrated a deficit in memory retrieval. For BOLD fMRI data, NU subjects exhibited greater activation in the right parahippocampal gyrus and cingulate gyrus compared to the MJ group for the Retrieval - Motor control contrast (NU > MJ). These findings suggest that hypoactivation in MJ users may be due to differences in the efficient utilization of neuronal resources during the retrieval of memory. Given the paucity of data on visuospatial memory function in MJ users, these findings may help elucidate the neurobiological effects of marijuana on brain activation during memory retrieval. PMID:23951549

  4. Pattern of brain activation during social cognitive tasks is related to social competence in siblings discordant for schizophrenia.

    PubMed

    Villarreal, Mirta F; Drucaroff, Lucas J; Goldschmidt, Micaela G; de Achával, Delfina; Costanzo, Elsa Y; Castro, Mariana N; Ladrón-de-Guevara, M Soledad; Busatto Filho, Geraldo; Nemeroff, Charles B; Guinjoan, Salvador M

    2014-09-01

    Measures of social competence are closely related to actual community functioning in patients with schizophrenia. However, the neurobiological mechanisms underlying competence in schizophrenia are not fully understood. We hypothesized that social deficits in schizophrenia are explained, at least in part, by abnormally lateralized patterns of brain activation in response to tasks engaging social cognition, as compared to healthy individuals. We predicted such patterns would be partly heritable, and therefore affected in patients' nonpsychotic siblings as well. We used a functional magnetic resonance image paradigm to characterize brain activation induced by theory of mind tasks, and two tests of social competence, the Test of Adaptive Behavior in Schizophrenia (TABS), and the Social Skills Performance Assessment (SSPA) in siblings discordant for schizophrenia and comparable healthy controls (n = 14 per group). Healthy individuals showed the strongest correlation between social competence and activation of right hemisphere structures involved in social cognitive processing, whereas in patients, the correlation pattern was lateralized to left hemisphere areas. Unaffected siblings of patients exhibited a pattern intermediate between the other groups. These results support the hypothesis that schizophrenia may be characterized by an abnormal functioning of nondominant hemisphere structures involved in the processing of socially salient information. PMID:24927685

  5. The interacting role of media violence exposure and aggressive-disruptive behavior in adolescent brain activation during an emotional Stroop task.

    PubMed

    Kalnin, Andrew J; Edwards, Chad R; Wang, Yang; Kronenberger, William G; Hummer, Tom A; Mosier, Kristine M; Dunn, David W; Mathews, Vincent P

    2011-04-30

    Only recently have investigations of the relationship between media violence exposure (MVE) and aggressive behavior focused on brain functioning. In this study, we examined the relationship between brain activation and history of media violence exposure in adolescents, using functional magnetic resonance imaging (fMRI). Samples of adolescents with no psychiatric diagnosis or with disruptive behavior disorder (DBD) with aggression were compared to investigate whether the association of MVE history and brain activation is moderated by aggressive behavior/personality. Twenty-two adolescents with a history of aggressive behavior and diagnosis of either conduct disorder or oppositional-defiant disorder (DBD sample) and 22 controls completed an emotional Stroop task during fMRI. Primary imaging results indicated that controls with a history of low MVE demonstrated greater activity in the right inferior frontal gyrus and rostral anterior cingulate during the violent word condition. In contrast, in adolescents with DBD, those with high MVE exhibited decreased activation in the right amygdala, compared with those with low MVE. These findings are consistent with research demonstrating the importance of fronto-limbic structures for processing emotional stimuli, and with research suggesting that media violence may affect individuals in different ways depending on the presence of aggressive traits. PMID:21376543

  6. Developing Analytic Rating Guides for "TOEFL iBT"® Integrated Speaking Tasks. "TOEFL iBT"® Research Report, TOEFL iBT-20. ETS Research Report. RR-13-13

    ERIC Educational Resources Information Center

    Jamieson, Joan; Poonpon, Kornwipa

    2013-01-01

    Research and development of a new type of scoring rubric for the integrated speaking tasks of "TOEFL iBT"® are described. These "analytic rating guides" could be helpful if tasks modeled after those in TOEFL iBT were used for formative assessment, a purpose which is different from TOEFL iBT's primary use for admission…

  7. Update on U.S.EPA Cookstove Research Activities

    EPA Science Inventory

    The presentation includes background information on EPA's stove research, focuses on cookstove testing for air pollutant emissions and energy efficiency, and briefly describes current research activities. Ongoing activities are highlighted, and EPA contacts are provided.

  8. Task Shifting Provision of Contraceptive Implants to Community Health Extension Workers: Results of Operations Research in Northern Nigeria

    PubMed Central

    Oguntunde, Olugbenga; Orobaton, Nosa; Otolorin, Emmanuel; Inuwa, Fatima; Alalade, Olubisi; Abegunde, Dele; Danladi, Saba’atu

    2015-01-01

    Background: Contraceptive use remains low in Nigeria, with only 11% of women reporting use of any modern method. Access to long-acting reversible contraceptives (LARCs) is constrained by a severe shortage of human resources. To assess feasibility of task shifting provision of implants, we trained community health extension workers (CHEWs) to insert and remove contraceptive implants in rural communities of Bauchi and Sokoto states in northern Nigeria. Methods: We conducted 2- to 3-week training sessions for 166 selected CHEWs from 82 facilities in Sokoto state (September 2013) and 84 health facilities in Bauchi state (December 2013). To assess feasibility of the task shifting approach, we conducted operations research using a pretest–posttest design using multiple sources of information, including surveys with 151 trained CHEWs (9% were lost to follow-up) and with 150 family planning clients; facility observations using supply checklists (N = 149); direct observation of counseling provided by CHEWs (N = 144) and of their clinical (N = 113) skills; as well as a review of service statistics (N = 151 health facilities). The endline assessment was conducted 6 months after the training in each state. Results: CHEWs inserted a total of 3,588 implants in 151 health facilities over a period of 6 months, generating 10,088 couple-years of protection (CYP). After practicing on anatomic arm models, most CHEWs achieved competency in implant insertions after insertions with 4–5 actual clients. Clinical observations revealed that CHEWs performed implant insertion tasks correctly 90% of the time or more for nearly all checklist items. The amount of information that CHEWs provided clients increased between baseline and endline, and over 95% of surveyed clients reported being satisfied with CHEWs’ services in both surveys. The study found that supervisors not only observed and corrected insertion skills, as needed, during supervisory visits but also encouraged

  9. Optical Topography of Evoked Brain Activity during Mental Tasks Involving Whole Number Operations

    ERIC Educational Resources Information Center

    Ortiz, Enrique

    2014-01-01

    Students start to memorize arithmetic facts from early elementary school mathematics activities. Their fluency or lack of fluency with these facts could affect their efforts as they carry out mental calculations as adults. This study investigated participants' levels of brain activation and possible reasons for these levels as they solved…

  10. The Masked Semantic Priming Effect Is Task Dependent: Reconsidering the Automatic Spreading Activation Process

    ERIC Educational Resources Information Center

    de Wit, Bianca; Kinoshita, Sachiko

    2015-01-01

    Semantic priming effects are popularly explained in terms of an automatic spreading activation process, according to which the activation of a node in a semantic network spreads automatically to interconnected nodes, preactivating a semantically related word. It is expected from this account that semantic priming effects should be routinely…

  11. Cost-effectiveness analysis alongside clinical trials II-An ISPOR Good Research Practices Task Force report.

    PubMed

    Ramsey, Scott D; Willke, Richard J; Glick, Henry; Reed, Shelby D; Augustovski, Federico; Jonsson, Bengt; Briggs, Andrew; Sullivan, Sean D

    2015-03-01

    Clinical trials evaluating medicines, medical devices, and procedures now commonly assess the economic value of these interventions. The growing number of prospective clinical/economic trials reflects both widespread interest in economic information for new technologies and the regulatory and reimbursement requirements of many countries that now consider evidence of economic value along with clinical efficacy. As decision makers increasingly demand evidence of economic value for health care interventions, conducting high-quality economic analyses alongside clinical studies is desirable because they broaden the scope of information available on a particular intervention, and can efficiently provide timely information with high internal and, when designed and analyzed properly, reasonable external validity. In 2005, ISPOR published the Good Research Practices for Cost-Effectiveness Analysis Alongside Clinical Trials: The ISPOR RCT-CEA Task Force report. ISPOR initiated an update of the report in 2014 to include the methodological developments over the last 9 years. This report provides updated recommendations reflecting advances in several areas related to trial design, selecting data elements, database design and management, analysis, and reporting of results. Task force members note that trials should be designed to evaluate effectiveness (rather than efficacy) when possible, should include clinical outcome measures, and should obtain health resource use and health state utilities directly from study subjects. Collection of economic data should be fully integrated into the study. An incremental analysis should be conducted with an intention-to-treat approach, complemented by relevant subgroup analyses. Uncertainty should be characterized. Articles should adhere to established standards for reporting results of cost-effectiveness analyses. Economic studies alongside trials are complementary to other evaluations (e.g., modeling studies) as information for decision

  12. Nursing Research--Taking an Active Interest.

    ERIC Educational Resources Information Center

    Cleverly, Dankay

    1998-01-01

    In Britain, nurses' attitudes toward research are changing. Schools of nursing must consider the following research issues: funding, contracts, support, publication, and staff recruitment and retention. (SK)

  13. Orexin receptor activity in the basal forebrain alters performance on an olfactory discrimination task.

    PubMed

    Piantadosi, Patrick T; Holmes, Ashley; Roberts, Bradley M; Bailey, Aileen M

    2015-01-12

    Cholinergic innervation of the prefrontal cortex is critical for various forms of cognition, although the efferent modulators contributing to acetylcholine (ACh) release are not well understood. The main source of cortical ACh, the basal forebrain, receives projections from lateral and perifornical hypothalamic neurons releasing the peptides orexin (orexin A; OxA, and orexin B; OxB), of which OxA is hypothesized to play a role in various cognitive functions. We sought to assess one such function known to be susceptible to basal forebrain cholinergic manipulation, olfactory discrimination acquisition, and reversal learning, in rats following intra-basal forebrain infusion of OxA or the orexin 1 receptor (OxR1) antagonist SB-334867. OxA administration facilitated, while OxR1 antagonism impaired performance on both the acquisition and reversal portions of the task. These data suggest that orexin acting in the basal forebrain may be important for cortical-dependant executive functions, possibly through the stimulation of cortical ACh release.

  14. Altered brain activation in a reversal learning task unmasks adaptive changes in cognitive control in writer's cramp.

    PubMed

    Zeuner, Kirsten E; Knutzen, Arne; Granert, Oliver; Sablowsky, Simone; Götz, Julia; Wolff, Stephan; Jansen, Olav; Dressler, Dirk; Schneider, Susanne A; Klein, Christine; Deuschl, Günther; van Eimeren, Thilo; Witt, Karsten

    2016-01-01

    Previous receptor binding studies suggest dopamine function is altered in the basal ganglia circuitry in task-specific dystonia, a condition characterized by contraction of agonist and antagonist muscles while performing specific tasks. Dopamine plays a role in reward-based learning. Using fMRI, this study compared 31 right-handed writer's cramp patients to 35 controls in reward-based learning of a probabilistic reversal-learning task. All subjects chose between two stimuli and indicated their response with their left or right index finger. One stimulus response was rewarded 80%, the other 20%. After contingencies reversal, the second stimulus response was rewarded in 80%. We further linked the DRD2/ANKK1-TaqIa polymorphism, which is associated with 30% reduction of the striatal dopamine receptor density with reward-based learning and assumed impaired reversal learning in A + subjects. Feedback learning in patients was normal. Blood-oxygen level dependent (BOLD) signal in controls increased with negative feedback in the insula, rostral cingulate cortex, middle frontal gyrus and parietal cortex (pFWE < 0.05). In comparison to controls, patients showed greater increase in BOLD activity following negative feedback in the dorsal anterior cingulate cortex (BA32). The genetic status was not correlated with the BOLD activity. The Brodmann area 32 (BA32) is part of the dorsal anterior cingulate cortex (dACC) that plays an important role in coordinating and integrating information to guide behavior and in reward-based learning. The dACC is connected with the basal ganglia-thalamo-loop modulated by dopaminergic signaling. This finding suggests disturbed integration of reinforcement history in decision making and implicate that the reward system might contribute to the pathogenesis in writer's cramp. PMID:26702397

  15. Altered brain activation in a reversal learning task unmasks adaptive changes in cognitive control in writer's cramp.

    PubMed

    Zeuner, Kirsten E; Knutzen, Arne; Granert, Oliver; Sablowsky, Simone; Götz, Julia; Wolff, Stephan; Jansen, Olav; Dressler, Dirk; Schneider, Susanne A; Klein, Christine; Deuschl, Günther; van Eimeren, Thilo; Witt, Karsten

    2016-01-01

    Previous receptor binding studies suggest dopamine function is altered in the basal ganglia circuitry in task-specific dystonia, a condition characterized by contraction of agonist and antagonist muscles while performing specific tasks. Dopamine plays a role in reward-based learning. Using fMRI, this study compared 31 right-handed writer's cramp patients to 35 controls in reward-based learning of a probabilistic reversal-learning task. All subjects chose between two stimuli and indicated their response with their left or right index finger. One stimulus response was rewarded 80%, the other 20%. After contingencies reversal, the second stimulus response was rewarded in 80%. We further linked the DRD2/ANKK1-TaqIa polymorphism, which is associated with 30% reduction of the striatal dopamine receptor density with reward-based learning and assumed impaired reversal learning in A + subjects. Feedback learning in patients was normal. Blood-oxygen level dependent (BOLD) signal in controls increased with negative feedback in the insula, rostral cingulate cortex, middle frontal gyrus and parietal cortex (pFWE < 0.05). In comparison to controls, patients showed greater increase in BOLD activity following negative feedback in the dorsal anterior cingulate cortex (BA32). The genetic status was not correlated with the BOLD activity. The Brodmann area 32 (BA32) is part of the dorsal anterior cingulate cortex (dACC) that plays an important role in coordinating and integrating information to guide behavior and in reward-based learning. The dACC is connected with the basal ganglia-thalamo-loop modulated by dopaminergic signaling. This finding suggests disturbed integration of reinforcement history in decision making and implicate that the reward system might contribute to the pathogenesis in writer's cramp.

  16. 20 CFR 401.165 - Statistical and research activities.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Statistical and research activities. 401.165... RECORDS AND INFORMATION Disclosure of Official Records and Information § 401.165 Statistical and research activities. (a) General. Statistical and research activities often do not require information in a...

  17. 20 CFR 401.165 - Statistical and research activities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Statistical and research activities. 401.165... RECORDS AND INFORMATION Disclosure of Official Records and Information § 401.165 Statistical and research activities. (a) General. Statistical and research activities often do not require information in a...

  18. 20 CFR 401.165 - Statistical and research activities.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Statistical and research activities. 401.165... RECORDS AND INFORMATION Disclosure of Official Records and Information § 401.165 Statistical and research activities. (a) General. Statistical and research activities often do not require information in a...

  19. 20 CFR 401.165 - Statistical and research activities.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false Statistical and research activities. 401.165... RECORDS AND INFORMATION Disclosure of Official Records and Information § 401.165 Statistical and research activities. (a) General. Statistical and research activities often do not require information in a...

  20. 20 CFR 401.165 - Statistical and research activities.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false Statistical and research activities. 401.165... RECORDS AND INFORMATION Disclosure of Official Records and Information § 401.165 Statistical and research activities. (a) General. Statistical and research activities often do not require information in a...