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Sample records for oddball task measured

  1. Do Rare Stimuli Evoke Large P3s by Being Unexpected? A Comparison of Oddball Effects Between Standard-Oddball and Prediction-Oddball Tasks

    PubMed Central

    Verleger, Rolf; Śmigasiewicz, Kamila

    2016-01-01

    The P3 component of event-related potentials increases when stimuli are rarely presented. It has been assumed that this oddball effect (rare-frequent difference) reflects the unexpectedness of rare stimuli. The assumption of unexpectedness and its link to P3 amplitude were tested here. A standard- oddball task requiring alternative key-press responses to frequent and rare stimuli was compared with an oddball-prediction task where stimuli had to be first predicted and then confirmed by key-pressing. Oddball effects in the prediction task depended on whether the frequent or the rare stimulus had been predicted. Oddball effects on P3 amplitudes and error rates in the standard oddball task closely resembled effects after frequent predictions. This corroborates the notion that these effects occur because frequent stimuli are expected and rare stimuli are unexpected. However, a closer look at the prediction task put this notion into doubt because the modifications of oddball effects on P3 by expectancies were entirely due to effects on frequent stimuli, whereas the large P3 amplitudes evoked by rare stimuli were insensitive to predictions (unlike response times and error rates). Therefore, rare stimuli cannot be said to evoke large P3 amplitudes because they are unexpected. We discuss these diverging effects of frequency and expectancy, as well as general differences between tasks, with respect to concepts and hypotheses about P3b’s function and conclude that each discussed concept or hypothesis encounters some problems, with a conception in terms of subjective relevance assigned to stimuli offering the most consistent account of these basic effects. PMID:27512527

  2. The Cognitive Locus of Distraction by Acoustic Novelty in the Cross-Modal Oddball Task

    ERIC Educational Resources Information Center

    Parmentier, Fabrice B. R.; Elford, Gregory; Escera, Carles; Andres, Pilar; San Miguel, Iria

    2008-01-01

    Unexpected stimuli are often able to distract us away from a task at hand. The present study seeks to explore some of the mechanisms underpinning this phenomenon. Studies of involuntary attention capture using the oddball task have repeatedly shown that infrequent auditory changes in a series of otherwise repeating sounds trigger an automatic…

  3. A comparative study of event-related coupling patterns during an auditory oddball task in schizophrenia

    NASA Astrophysics Data System (ADS)

    Bachiller, Alejandro; Poza, Jesús; Gómez, Carlos; Molina, Vicente; Suazo, Vanessa; Hornero, Roberto

    2015-02-01

    Objective. The aim of this research is to explore the coupling patterns of brain dynamics during an auditory oddball task in schizophrenia (SCH). Approach. Event-related electroencephalographic (ERP) activity was recorded from 20 SCH patients and 20 healthy controls. The coupling changes between auditory response and pre-stimulus baseline were calculated in conventional EEG frequency bands (theta, alpha, beta-1, beta-2 and gamma), using three coupling measures: coherence, phase-locking value and Euclidean distance. Main results. Our results showed a statistically significant increase from baseline to response in theta coupling and a statistically significant decrease in beta-2 coupling in controls. No statistically significant changes were observed in SCH patients. Significance. Our findings support the aberrant salience hypothesis, since SCH patients failed to change their coupling dynamics between stimulus response and baseline when performing an auditory cognitive task. This result may reflect an impaired communication among neural areas, which may be related to abnormal cognitive functions.

  4. Disruptions in small-world cortical functional connectivity network during an auditory oddball paradigm task in patients with schizophrenia.

    PubMed

    Shim, Miseon; Kim, Do-Won; Lee, Seung-Hwan; Im, Chang-Hwan

    2014-07-01

    P300 deficits in patients with schizophrenia have previously been investigated using EEGs recorded during auditory oddball tasks. However, small-world cortical functional networks during auditory oddball tasks and their relationships with symptom severity scores in schizophrenia have not yet been investigated. In this study, the small-world characteristics of source-level functional connectivity networks of EEG responses elicited by an auditory oddball paradigm were evaluated using two representative graph-theoretical measures, clustering coefficient and path length. EEG signals from 34 patients with schizophrenia and 34 healthy controls were recorded while each subject was asked to attend to oddball tones. The results showed reduced clustering coefficients and increased path lengths in patients with schizophrenia, suggesting that the small-world functional network is disrupted in patients with schizophrenia. In addition, the negative and cognitive symptom components of positive and negative symptom scales were negatively correlated with the clustering coefficient and positively correlated with path length, demonstrating that both indices are indicators of symptom severity in patients with schizophrenia. Our study results suggest that disrupted small-world characteristics are potential biomarkers for patients with schizophrenia.

  5. Dysfunctional Cortical Connectivity During the Auditory Oddball Task in Patients with Schizophrenia

    PubMed Central

    Fujimoto, Toshiro; Okumura, Eiichi; Takeuchi, Kouzou; Kodabashi, Atsushi; Otsubo, Toshiaki; Nakamura, Katsumi; Kamiya, Shinichiro; Higashi, Yuji; Yuji, Tadahiko; Honda, Kenichi; Shimooki, Susumu; Tamura, Toshiyo

    2013-01-01

    Background: We studied the imaginary coherence (IC) of gamma frequency oscillations between brain regions of male schizophrenia patients during an auditory oddball task using magnetoencephalography (MEG) and electroencephalography (EEG). Methods: Subjects were 10 right-handed male schizophrenia patients, evaluated by the positive and negative symptom scale (PANSS), and 10 healthy controls. Functional connectivity during the auditory oddball task was reconstructed in low (30-50 Hz) and high (50-100 Hz) gamma bands, and represented by imaginary coherence (IC) based on significant oscillatory power changes. We calculated correlations between PANSS scores and IC. Results: In the high gamma band, IC between left occipital and right prefrontal lobe areas during the time window 750-1000 ms from stimulus onset showed negative correlations with total negative scores, total positive scores, the sum of positive and negative scores in PANSS, conceptual disorganization, and social avoidance scores. In the low gamma band, IC between the same areas from 250-500 ms also showed a negative correlation with the conceptual disorganization score. In the same time window, IC between left occipital and right frontoparietal lobe areas in the low gamma band showed a positive correlation with hallucinatory behavior; IC between right temporal pole and left prefrontal lobe areas showed a positive correlation with delusion scores, although these ICs were decreased relative to controls. Conclusions: Functional disconnection of high and low gamma bands in auditory oddball task may play an important role in the auditory processing in schizophrenia patients. PMID:23750187

  6. Genetic effects on source level evoked and induced oscillatory brain responses in a visual oddball task.

    PubMed

    Antonakakis, Marios; Zervakis, Michalis; van Beijsterveldt, Catharina E M; Boomsma, Dorret I; De Geus, Eco J C; Micheloyannis, Sifis; Smit, Dirk J A

    2016-02-01

    Stimuli in simple oddball target detection paradigms cause evoked responses in brain potential. These responses are heritable traits, and potential endophenotypes for clinical phenotypes. These stimuli also cause responses in oscillatory activity, both evoked responses phase-locked to stimulus presentation and phase-independent induced responses. Here, we investigate whether phase-locked and phase-independent oscillatory responses are heritable traits. Oscillatory responses were examined in EEG recordings from 213 twin pairs (91 monozygotic and 122 dizygotic twins) performing a visual oddball task. After group Independent Component Analysis (group-ICA) and time-frequency decomposition, individual differences in evoked and induced oscillatory responses were compared between MZ and DZ twin pairs. Induced (phase-independent) oscillatory responses consistently showed the highest heritability (24-55%) compared to evoked (phase-locked) oscillatory responses and spectral energy, which revealed lower heritability at 1-35.6% and 4.5-32.3%, respectively. Since the phase-independent induced response encodes functional aspects of the brain response to target stimuli different from evoked responses, we conclude that the modulation of ongoing oscillatory activity may serve as an additional endophenotype for behavioral phenotypes and psychiatric genetics.

  7. EEG coherence obtained from an auditory oddball task increases with age.

    PubMed

    Maurits, Natasha M; Scheeringa, Rene; van der Hoeven, Johannes H; de Jong, Ritske

    2006-10-01

    Changes in coherence with aging during cognitive tasks have, until now, not been investigated. However, several fMRI and positron emission tomography studies of cognitive tasks have found increased bilateral activity in elderly subjects. Changes in coherence with aging during a cognitive task were investigated to see if EEG coherence was present in older adults. An auditory oddball task, which is a widely used test for cognitive function, was used. Eleven young adults (27.8 +/- 4.8 years, six females) and 10 older adults (61.3 +/- 4.6 years, six females) were studied, and both interhemispheric and long- and short-range intrahemispheric coherence were considered. Higher interhemispheric coherence was found in the older subjects in the delta band. Short intrahemispheric coherence was also increased in the theta, delta, and alpha bands. Higher coherence, although not significantly different, was also found for all other coherence types and bands, except for long intrahemispheric coherence in the low gamma band. The results presented here provide the first evidence that aging is associated with increased EEG coherence during a relatively easy cognitive task.

  8. Event-related potentials (ERPs) in ecstasy (MDMA) users during a visual oddball task.

    PubMed

    Mejias, S; Rossignol, M; Debatisse, D; Streel, E; Servais, L; Guérit, J M; Philippot, P; Campanella, S

    2005-07-01

    Ecstasy is the common name for a drug mainly containing a substance identified as 3,4-methylenedioxymethamphetamine (MDMA). It has become popular with participants in "raves", because it enhances energy, endurance and sexual arousal, together with the widespread belief that MDMA is a safe drug [Byard, R.W., Gilbert, J., James, R., Lokan, R.J., 1998. Amphetamine derivative fatalities in South Australia. Is "ecstasy" the culprit? Am. J. Forensic Med. Pathol. 19, 261-265]. However, it is suggested that this drug causes a neurotoxicity to the serotonergic system that could lead to permanent physical and cognitive problems. In order to investigate this issue, and during an ERP recording with 32 channels, we used a visual oddball design, in which subjects (14 MDMA abusers and 14 paired normal controls) saw frequent stimuli (neutral faces) while they had to detect as quickly as possible rare stimuli with happy or fearful expression. At a behavioral level, MDMA users imply longer latencies than normal controls to detect rare stimuli. At the neurophysiological level, ERP data suggest as main result that the N200 component, which is involved in attention orienting associated to the detection of stimulus novelty (e.g. [Campanella, S., Gaspard, C., Debatisse, D., Bruyer, R., Crommelinck, M., Guerit, J.M., 2002. Discrimination of emotional facial expression in a visual oddball task: an ERP study. Biol. Psychol. 59, 171-186]), shows shorter latencies for fearful rare stimuli (as compared to happy ones), but only for normal controls. This absence of delay was interpreted as an attentional deficit due to MDMA consumption. PMID:15925034

  9. Changes in Event-Related Desynchronization and Synchronization during the Auditory Oddball Task in Schizophrenia Patients

    PubMed Central

    Fujimoto, Toshiro; Okumura, Eiichi; Takeuchi, Kouzou; Kodabashi, Atsushi; Tanaka, Hiroaki; Otsubo, Toshiaki; Nakamura, Katsumi; Sekine, Masaki; Kamiya, Shinichiro; Higashi, Yuji; Tsuji, Miwa; Shimooki, Susumu; Tamura, Toshiyo

    2012-01-01

    Objective: We studied differences in the spatiotemporal dynamics of cortical oscillation across brain regions of patients with schizophrenia and normal subjects during the auditory oddball task using magnetoencephalography (MEG) and electroencephalography (EEG). Methods: Ten right-handed male schizophrenia patients were studied. We used a newly developed adaptive spatial filtering algorithm optimized for robust source time-frequency reconstruction of MEG and EEG data, and obtained consecutive images in functional maps of event-related desynchronization (ERD) and synchronization (ERS) in theta, lower alpha (8–10 Hz), upper alpha (10–13 Hz), and beta bands. Results: Beta ERD power at 750–1000 ms in patients was significantly increased in large right upper temporal and parietal regions and small upper portions of bilateral dorsal frontal and dorsal-medial parietal regions. Theta ERS power in schizophrenic patients during the oddball task was significantly increased in the left temporal pole at 250–500 ms, and was significantly increased in dorsal, medial frontal, and anterior portions of the anterior cingulate cortex in both hemispheres, and the left portion of lateral temporal regions at 500–750 ms, compared to the control group (family-wise error correction p<0.05). Lower alpha ERS power was significantly decreased in the right occipital region at 500–750 ms and in the right midline parietal and bilateral occipital regions at 750–1000 ms. Upper alpha ERS power was significantly decreased in right midline parietal and left occipital regions at 750–1000 ms. Conclusions: ERD/ERS changes were noted in the left temporal pole and midline frontal and anterior cingulate cortex in theta ERS, occipital lobe in alpha ERS, and right temporal-frontal-parietal, midline frontal, and anterior cingulate cortex in beta ERD. These findings may reflect disturbances in interaction among active large neuronal groups and their communication with each other that may be

  10. Neural correlates of emotional intelligence in a visual emotional oddball task: an ERP study.

    PubMed

    Raz, Sivan; Dan, Orrie; Zysberg, Leehu

    2014-11-01

    The present study was aimed at identifying potential behavioral and neural correlates of Emotional Intelligence (EI) by using scalp-recorded Event-Related Potentials (ERPs). EI levels were defined according to both self-report questionnaire and a performance-based ability test. We identified ERP correlates of emotional processing by using a visual-emotional oddball paradigm, in which subjects were confronted with one frequent standard stimulus (a neutral face) and two deviant stimuli (a happy and an angry face). The effects of these faces were then compared across groups with low and high EI levels. The ERP results indicate that participants with high EI exhibited significantly greater mean amplitudes of the P1, P2, N2, and P3 ERP components in response to emotional and neutral faces, at frontal, posterior-parietal and occipital scalp locations. P1, P2 and N2 are considered indexes of attention-related processes and have been associated with early attention to emotional stimuli. The later P3 component has been thought to reflect more elaborative, top-down, emotional information processing including emotional evaluation and memory encoding and formation. These results may suggest greater recruitment of resources to process all emotional and non-emotional faces at early and late processing stages among individuals with higher EI. The present study underscores the usefulness of ERP methodology as a sensitive measure for the study of emotional stimuli processing in the research field of EI.

  11. Consecutive repetition effects for affective-distractor pictures in a visual oddball task: electrophysiological evidence from an ERP study.

    PubMed

    Jiang, Donghong; Zheng, Xifu; Li, Fei

    2013-06-23

    Although repeated affective stimuli can promote habituation, most studies of event-related potentials (ERPs) have focused on habituation to targets that are repeated non-consecutively. However, the neural mechanisms underlying the consecutive repetition effects of affective-distractor stimuli are unclear. Using a three-stimulus oddball task (standard vs. target vs. distractor ratio: 60%:20%:20%) and measures of ERPs, we assessed the repetition effects of affective-distractor pictures that were repeated consecutively. Participants (N=16) were asked to distinguish the size of a geometric surface; they were asked to selectively respond to the target stimuli (larger geometric surfaces) and to ignore the standard stimuli (smaller geometric surfaces) and affective-distractor pictures. Forty pictures portraying a neutral affect and 40 pictures portraying a negative affect were taken from the Chinese Affective Picture System. Each picture was pseudo-randomly selected and consecutively repeated three times, and ERPs were recorded for the repeated affective-distractor pictures. Stimulus repetition was associated with amplitude increases for P3 and amplitude decreases for N1 and N2 as the presentations proceeded. Peak latency remained stable. The P2, N2, and P3 amplitudes were greater during negative vs. neutral pictures. The affective effects did not interact with stimulus repetition at any latency range. The results suggest that consecutive repetition and affective stimuli modulate ERP outcomes independently.

  12. The enhanced processing of visual novel events in females: ERP correlates from two modified three-stimulus oddball tasks.

    PubMed

    Yuan, Jiajin; Xu, Shuang; Li, Chengqiang; Yang, Jiemin; Li, Hong; Yuan, Yin; Huang, Yu

    2012-02-01

    The ability to detect and cope with unpredictable novel events is fundamental for adapting to a rapidly changing environment and ensuring the survival of the organism. Despite knowledge of gender differences in emotional processing, little is currently known about the impact of gender on neural processing of emotion-irrelevant, novel stimuli. Using two modified three-stimulus oddball tasks and event-related potentials (ERPs), the present study investigated the impact of sex on brain processing of novel events and the associated neurophysiological correlates. With novel and non-novel control stimuli used as task-irrelevant distracters, Experiment 1 showed higher novelty rating scores and larger size of novelty effects in brain potentials at 200-300 ms and 300-430 ms time intervals in females compared to males. After excluding the contribution of stimulus probability, Experiment 2 continued to display significant novelty effects in the response times and the amplitudes of the 130-500 ms time windows. Most importantly, females displayed a sustained novelty effect in the late positive component (LPC) amplitudes of the 500-600 ms interval, which was not observed in males. Therefore, Experiment 1 and 2 demonstrated that females are equipped with enhanced brain processing of emotion-irrelevant, novel stimuli. This phenomenon is independent of the established gender difference in infrequent stimulus processing. We suggest that our findings reflect the differential adaptive demands on females and males during evolution. PMID:22230670

  13. Single-trial discrimination for integrating simultaneous EEG and fMRI: Identifying cortical areas contributing to trial-to-trial variability in the auditory oddball task

    PubMed Central

    Goldman, Robin I; Wei, Cheng-Yu; Philiastides, Marios G.; Gerson, Adam D.; Friedman, David; Brown, Truman R.; Sajda, Paul

    2009-01-01

    The auditory oddball task is a well-studied stimulus paradigm used to investigate the neural correlates of simple target detection. It elicits several classic event-related potentials (ERPs), the most prominent being the P300 which is seen as a neural correlate of subjects' detection of rare (target) stimuli. Though trial-averaging is typically used to identify and characterize such ERPs, their latency and amplitude can vary on a trial-to-trial basis reflecting variability in the underlying neural information processing. Here we simultaneously recorded EEG and fMRI during an auditory oddball task and identified cortical areas correlated with the trial-to-trial variability of task-discriminating EEG components. Unique to our approach is a linear multivariate method for identifying task-discriminating components within specific stimulus- or response- locked time windows. We find fMRI activations indicative of distinct processes that contribute to the single-trial variability during target detection. These regions are different from those found using standard, including trial-averaged, regressors. Of particular note is strong activation of the lateral occipital complex (LOC). The LOC was not seen when using traditional event-related regressors. Though LOC is typically associated with visual/spatial attention, its activation in an auditory oddball task, where attention can wax and wane from trial-to-trial, indicates it may be part of a more general attention network involved in allocating resources for target detection and decision making. Our results show that trial-to-trial variability in EEG components, acquired simultaneously with fMRI, can yield task-relevant BOLD activations that are otherwise unobservable using traditional fMRI analysis. PMID:19345734

  14. Testing the S-R link hypothesis of P3b: The oddball effect on S1-evoked P3 gets reduced by increased task relevance of S2.

    PubMed

    Verleger, Rolf; Hamann, Lin Marlena; Asanowicz, Dariusz; Śmigasiewicz, Kamila

    2015-05-01

    We had previously reported that the oddball effect on the P3b EEG potential evoked by infrequent vs. frequent S1 presented in a sequence of two stimuli, S1 and S2, gets reduced in a "combination task". In this task, responses were determined by the combinations of S1 and S2 rather than by S1 only. We had attributed this reduction of the oddball effect to increased task difficulty. The present study investigated possible reasons for this reduction of S1-evoked P3b in more detail, by making the combination task easier in several respects: allowing for forming associations from S1 to responses (Experiment 1), reducing the complexity of stimulus-response (S-R) mappings (Experiment 2), and decreasing S2 relevance in defining responses (Experiment 3). The results showed that only S2 relevance affected the oddball effect on S1-evoked P3b. Namely, when S2 attained some relevance by inducing a go/no-go decision for S1-defined responses, the oddball effect on S1-evoked P3b was intermediate between the large effect in the simple oddball task and the small effect in the combination task. The results may be explained in terms of the S-R link hypothesis of P3b which interprets P3b as reflecting reactivation of well-established S-R links.

  15. The impact of motor activity on intracerebral ERPs: P3 latency variability in modified auditory odd-ball paradigms involving a motor task.

    PubMed

    Kanovský, Petr; Streitová, Hana; Klajblová, Hana; Bares, Martin; Daniel, Pavel; Rektor, Ivan

    2003-09-01

    The P3 wave of event-related potentials was recorded with intracranial electrodes in 24 epileptic patients during the pre-surgical evaluation of epilepsy surgery. Three different cognitive auditory paradigms were used: (1) odd-ball paradigm with no output required (PGI) where patients had simply to recognize target tones, (2) odd-ball with motor response (PGII), where patients had to press a button in response to target tones, and (3) odd-ball with both counting task and motor response (PGIII), where patients had to recognize target tones, press a button in response to them, and count their number. The occurrence of P3 potential, its latency and amplitude, and the dependence of P3 latency on the task complexity were calculated. Identifiable P3 potentials in all the three paradigms were recorded from locations in mesial cortex (18 locations mesial temporal, eight locations mesial frontal, two locations mesial parietal) and lateral sites (eight sites lateral temporal, five lateral frontal, and two lateral parietal). P3 latency values ranged from 257 to 320 ms in all explored cortical areas when PGI was used; they significantly increased or decreased during PGII and PGIII, depending on the task and structure explored. In the mesial temporal cortex, the changes of P3 latency between paradigms were minimal. In the mesial parietal cortex, there was significant P3 delay in both PGII and PGIII relative to PGI. In the mesial frontal cortex, there was a significant latency decrease in PGII, and practically identical mean latency in PGI and PGIII. In all lateral cortices (temporal, frontal and parietal), there was always a P3 latency increase in PGII and PGIII relative to PGI, the most significant results being observed in the parietal and frontal lateral areas. The results support the multi-generator theory of P3. Prolongation of the mean P3 latency in lateral frontal and parietal cortices when the paradigm involved the execution of a motor task might reflect specific gating

  16. Event related potentials from closed head injury patients in an auditory "oddball" task: evidence of dysfunction in stimulus categorisation.

    PubMed Central

    Rugg, M D; Cowan, C P; Nagy, M E; Milner, A D; Jacobson, I; Brooks, D N

    1988-01-01

    Event-related potentials (ERPs) were recorded from 19 closed head injury (CHI) patients, at least 6 months after injury, and an equal number of control subjects, during a task requiring the covert counting of rare auditory "target" stimuli against a background of frequent "non-targets". In both groups, ERPs to targets contained enhanced frontal N2 and parietal P3 components. N2 was larger in amplitude in the CHI patients than in the controls, and its peak latency was delayed. P3 amplitude was smaller in the patients, but its latency was not significantly different from that of the control group. The delay in N2 latency is interpreted as evidence of an increase in the time needed to achieve stimulus categorisation in CHI patients. The larger N2s in this group are thought to reflect the additional cognitive effort required after CHI to cope with the task. The negative findings with respect to P3 latency suggest that this may be a less sensitive measure of information-processing efficiency in this task than the latency of N2. PMID:3404166

  17. Sex Differences in Gamma Band Functional Connectivity Between the Frontal Lobe and Cortical Areas During an Auditory Oddball Task, as Revealed by Imaginary Coherence Assessment

    PubMed Central

    Fujimoto, Toshiro; Okumura, Eiichi; Kodabashi, Atsushi; Takeuchi, Kouzou; Otsubo, Toshiaki; Nakamura, Katsumi; Yatsushiro, Kazutaka; Sekine, Masaki; Kamiya, Shinichiro; Shimooki, Susumu; Tamura, Toshiyo

    2016-01-01

    We studied sex-related differences in gamma oscillation during an auditory oddball task, using magnetoencephalography and electroencephalography assessment of imaginary coherence (IC). We obtained a statistical source map of event-related desynchronization (ERD) / event-related synchronization (ERS), and compared females and males regarding ERD / ERS. Based on the results, we chose respectively seed regions for IC determinations in low (30-50 Hz), mid (50-100 Hz) and high gamma (100-150 Hz) bands. In males, ERD was increased in the left posterior cingulate cortex (CGp) at 500 ms in the low gamma band, and in the right caudal anterior cingulate cortex (cACC) at 125 ms in the mid-gamma band. ERS was increased in the left rostral anterior cingulate cortex (rACC) at 375 ms in the high gamma band. We chose the CGp, cACC and rACC as seeds, and examined IC between the seed and certain target regions using the IC map. IC changes depended on the height of the gamma frequency and the time window in the gamma band. Although IC in the mid and high gamma bands did not show sex-specific differences, IC at 30-50 Hz in males was increased between the left rACC and the frontal, orbitofrontal, inferior temporal and fusiform target regions. Increased IC in males suggested that males may acomplish the task constructively, analysingly, emotionally, and by perfoming analysis, and that information processing was more complicated in the cortico-cortical circuit. On the other hand, females showed few differences in IC. Females planned the task with general attention and economical well-balanced processing, which was explained by the higher overall functional cortical connectivity. CGp, cACC and rACC were involved in sex differences in information processing and were likely related to differences in neuroanatomy, hormones and neurotransmitter systems. PMID:27708745

  18. Brain Dynamics of Aging: Multiscale Variability of EEG Signals at Rest and during an Auditory Oddball Task(1,2,3).

    PubMed

    Sleimen-Malkoun, Rita; Perdikis, Dionysios; Müller, Viktor; Blanc, Jean-Luc; Huys, Raoul; Temprado, Jean-Jacques; Jirsa, Viktor K

    2015-01-01

    The present work focused on the study of fluctuations of cortical activity across time scales in young and older healthy adults. The main objective was to offer a comprehensive characterization of the changes of brain (cortical) signal variability during aging, and to make the link with known underlying structural, neurophysiological, and functional modifications, as well as aging theories. We analyzed electroencephalogram (EEG) data of young and elderly adults, which were collected at resting state and during an auditory oddball task. We used a wide battery of metrics that typically are separately applied in the literature, and we compared them with more specific ones that address their limits. Our procedure aimed to overcome some of the methodological limitations of earlier studies and verify whether previous findings can be reproduced and extended to different experimental conditions. In both rest and task conditions, our results mainly revealed that EEG signals presented systematic age-related changes that were time-scale-dependent with regard to the structure of fluctuations (complexity) but not with regard to their magnitude. Namely, compared with young adults, the cortical fluctuations of the elderly were more complex at shorter time scales, but less complex at longer scales, although always showing a lower variance. Additionally, the elderly showed signs of spatial, as well as between, experimental conditions dedifferentiation. By integrating these so far isolated findings across time scales, metrics, and conditions, the present study offers an overview of age-related changes in the fluctuation electrocortical activity while making the link with underlying brain dynamics. PMID:26464983

  19. Brain Dynamics of Aging: Multiscale Variability of EEG Signals at Rest and during an Auditory Oddball Task1,2,3

    PubMed Central

    Sleimen-Malkoun, Rita; Perdikis, Dionysios; Müller, Viktor; Blanc, Jean-Luc; Huys, Raoul; Temprado, Jean-Jacques

    2015-01-01

    Abstract The present work focused on the study of fluctuations of cortical activity across time scales in young and older healthy adults. The main objective was to offer a comprehensive characterization of the changes of brain (cortical) signal variability during aging, and to make the link with known underlying structural, neurophysiological, and functional modifications, as well as aging theories. We analyzed electroencephalogram (EEG) data of young and elderly adults, which were collected at resting state and during an auditory oddball task. We used a wide battery of metrics that typically are separately applied in the literature, and we compared them with more specific ones that address their limits. Our procedure aimed to overcome some of the methodological limitations of earlier studies and verify whether previous findings can be reproduced and extended to different experimental conditions. In both rest and task conditions, our results mainly revealed that EEG signals presented systematic age-related changes that were time-scale-dependent with regard to the structure of fluctuations (complexity) but not with regard to their magnitude. Namely, compared with young adults, the cortical fluctuations of the elderly were more complex at shorter time scales, but less complex at longer scales, although always showing a lower variance. Additionally, the elderly showed signs of spatial, as well as between, experimental conditions dedifferentiation. By integrating these so far isolated findings across time scales, metrics, and conditions, the present study offers an overview of age-related changes in the fluctuation electrocortical activity while making the link with underlying brain dynamics. PMID:26464983

  20. Selective adaptation to "oddball" sounds by the human auditory system.

    PubMed

    Simpson, Andrew J R; Harper, Nicol S; Reiss, Joshua D; McAlpine, David

    2014-01-29

    Adaptation to both common and rare sounds has been independently reported in neurophysiological studies using probabilistic stimulus paradigms in small mammals. However, the apparent sensitivity of the mammalian auditory system to the statistics of incoming sound has not yet been generalized to task-related human auditory perception. Here, we show that human listeners selectively adapt to novel sounds within scenes unfolding over minutes. Listeners' performance in an auditory discrimination task remains steady for the most common elements within the scene but, after the first minute, performance improves for distinct and rare (oddball) sound elements, at the expense of rare sounds that are relatively less distinct. Our data provide the first evidence of enhanced coding of oddball sounds in a human auditory discrimination task and suggest the existence of an adaptive mechanism that tracks the long-term statistics of sounds and deploys coding resources accordingly. PMID:24478375

  1. Oddballs and a Low Odderon Intercept

    SciTech Connect

    Llanes-Estrada, Felipe J.; Bicudo, Pedro; Cotanch, Stephen R.; /North Carolina State U.

    2005-07-27

    The authors report an odderon Regge trajectory emerging from a field theoretical Coulomb gauge QCD model for the odd signature J{sup PC} (P = C = -1) glueball states (oddballs). The trajectory intercept is clearly smaller than the pomeron and even the {omega} trajectory's intercept which provides an explanation for the nonobservation of the odderon in high energy scattering data. To further support this result we compare to glueball lattice data and also perform calculations with an alternative model based upon an exact Hamiltonian diagonalization for three constituent gluons.

  2. Electrical mapping in bipolar disorder patients during the oddball paradigm.

    PubMed

    Di Giorgio Silva, Luiza Wanick; Cartier, Consuelo; Cheniaux, Elie; Novis, Fernanda; Silveira, Luciana Angélica; Cavaco, Paola Anaquim; de Assis da Silva, Rafael; Batista, Washington Adolfo; Tanaka, Guaraci Ken; Gongora, Mariana; Bittencourt, Juliana; Teixeira, Silmar; Basile, Luis Fernando; Budde, Henning; Cagy, Mauricio; Ribeiro, Pedro; Velasques, Bruna

    2016-01-01

    Bipolar disorder (BD) is characterized by an alternated occurrence between acute mania episodes and depression or remission moments. The objective of this study is to analyze the information processing changes in BP (Bipolar Patients) (euthymia, depression and mania) during the oddball paradigm, focusing on the P300 component, an electric potential of the cerebral cortex generated in response to external sensorial stimuli, which involves more complex neurophysiological processes related to stimulus interpretation. Twenty-eight bipolar disorder patients (BP) (17 women and 11 men with average age of 32.5, SD: 9.5) and eleven healthy controls (HC) (7 women and 4 men with average age of 29.78, SD: 6.89) were enrolled in this study. The bipolar patients were divided into 3 major groups (i.e., euthymic, depressive and maniac) according to the score on the Clinical Global Impression--Bipolar Version (CGI-BP). The subjects performed the oddball paradigm simultaneously to the EEG record. EEG data were also recorded before and after the execution of the task. A one-way ANOVA was applied to compare the P300 component among the groups. After observing P300 and the subcomponents P3a and P3b, a similarity of amplitude and latency between euthymic and depressive patients was observed, as well as small amplitude in the pre-frontal cortex and reduced P3a response. This can be evidence of impaired information processing, cognitive flexibility, working memory, executive functions and ability to shift the attention and processing to the target and away from distracting stimuli in BD. Such neuropsychological impairments are related to different BD symptoms, which should be known and considered, in order to develop effective clinical treatment strategies. PMID:26551764

  3. Methodological Considerations about the Use of Bimodal Oddball P300 in Psychiatry: Topography and Reference Effect

    PubMed Central

    Schröder, Elisa; Kajosch, Hendrik; Verbanck, Paul; Kornreich, Charles; Campanella, Salvatore

    2016-01-01

    Event-related potentials (ERPs) bimodal oddball task has disclosed increased sensitivity to show P300 modulations to subclinical symptoms. Even if the utility of such a procedure has still to be confirmed at a clinical level, gathering normative values of this new oddball variant may be of the greatest interest. We specifically addressed the challenge of defining the best location for the recording of P3a and P3b components and selecting the best reference to use by investigating the effect of an offline re-reference procedure on recorded bimodal P3a and P3b. Forty young and healthy subjects were submitted to a bimodal (synchronized and always congruent visual and auditory stimuli) three-stimulus oddball task in which 140 frequent bimodal stimuli, 30 deviant “target” stimuli and 30 distractors were presented. Task consisted in clicking as soon as possible on the targets, and not paying attention to frequent stimuli and distractors. This procedure allowed us to record, for each individual, the P3a component, referring to the novelty process related to distractors processing, and the P3b component, linked to the processing of the target stimuli. Results showed that both P3a and P3b showed maximal amplitude in Pz. However, P3a displayed a more central distribution. Nose reference was also shown to give maximal amplitudes compared with average and linked mastoids references. These data were discussed in light of the necessity to develop multi-site recording guidelines to furnish sets of ERPs data comparable across laboratories. PMID:27708597

  4. Structure and Topology Dynamics of Hyper-Frequency Networks during Rest and Auditory Oddball Performance

    PubMed Central

    Müller, Viktor; Perdikis, Dionysios; von Oertzen, Timo; Sleimen-Malkoun, Rita; Jirsa, Viktor; Lindenberger, Ulman

    2016-01-01

    Resting-state and task-related recordings are characterized by oscillatory brain activity and widely distributed networks of synchronized oscillatory circuits. Electroencephalographic recordings (EEG) were used to assess network structure and network dynamics during resting state with eyes open and closed, and auditory oddball performance through phase synchronization between EEG channels. For this assessment, we constructed a hyper-frequency network (HFN) based on within- and cross-frequency coupling (WFC and CFC, respectively) at 10 oscillation frequencies ranging between 2 and 20 Hz. We found that CFC generally differentiates between task conditions better than WFC. CFC was the highest during resting state with eyes open. Using a graph-theoretical approach (GTA), we found that HFNs possess small-world network (SWN) topology with a slight tendency to random network characteristics. Moreover, analysis of the temporal fluctuations of HFNs revealed specific network topology dynamics (NTD), i.e., temporal changes of different graph-theoretical measures such as strength, clustering coefficient, characteristic path length (CPL), local, and global efficiency determined for HFNs at different time windows. The different topology metrics showed significant differences between conditions in the mean and standard deviation of these metrics both across time and nodes. In addition, using an artificial neural network approach, we found stimulus-related dynamics that varied across the different network topology metrics. We conclude that functional connectivity dynamics (FCD), or NTD, which was found using the HFN approach during rest and stimulus processing, reflects temporal and topological changes in the functional organization and reorganization of neuronal cell assemblies. PMID:27799906

  5. Heart rate variability and cognitive processing: The autonomic response to task demands.

    PubMed

    Luque-Casado, Antonio; Perales, José C; Cárdenas, David; Sanabria, Daniel

    2016-01-01

    This study investigated variations in heart rate variability (HRV) as a function of cognitive demands. Participants completed an execution condition including the psychomotor vigilance task, a working memory task and a duration discrimination task. The control condition consisted of oddball versions (participants had to detect the rare event) of the tasks from the execution condition, designed to control for the effect of the task parameters (stimulus duration and stimulus rate) on HRV. The NASA-TLX questionnaire was used as a subjective measure of cognitive workload across tasks and conditions. Three major findings emerged from this study. First, HRV varied as a function of task demands (with the lowest values in the working memory task). Second, and crucially, we found similar HRV values when comparing each of the tasks with its oddball control equivalent, and a significant decrement in HRV as a function of time-on-task. Finally, the NASA-TLX results showed larger cognitive workload in the execution condition than in the oddball control condition, and scores variations as a function of task. Taken together, our results suggest that HRV is highly sensitive to overall demands of sustained attention over and above the influence of other cognitive processes suggested by previous literature. In addition, our study highlights a potential dissociation between objective and subjective measures of mental workload, with important implications in applied settings.

  6. Posterior EEG alpha at rest and during task performance: Comparison of current source density and field potential measures

    PubMed Central

    Tenke, Craig E.; Kayser, Jürgen; Abraham, Karen; Alvarenga, Jorge E.; Bruder, Gerard E.

    2015-01-01

    Resting and task-related EEG alpha are used in studies of cognition and psychopathogy. Although Laplacian methods have been applied, apprehensions about loss of global activity dissuade researchers from greater use except as a supplement to reference-dependent measures. The unfortunate result has been continued reliance on reference strategies that differ across labs, and a systemic preference for a montage-dependent average reference over true reference-free measures. We addressed these concerns by comparing resting- and task-related EEG alpha using three EEG transformations: nose- (NR) and average-referenced (AR) EEG, and the corresponding CSD. Amplitude spectra of resting and prestimulus task-related EEG (novelty oddball) and event-related spectral perturbations were scaled to equate each transformation. Alpha measures quantified for 8-12 Hz bands were: 1) net amplitude (eyes-closed minus eyes-open) and 2) overall amplitude (eyes-closed plus eyes-open); 3) task amplitude (prestimulus baseline) and 4) task event-related desynchronization (ERD). Mean topographies unambiguously represented posterior alpha for overall, net and task, as well as poststimulus alpha ERD. Topographies were similar for the three transformations, but differed in dispersion, CSD being sharpest and NR most broadly distributed. Transformations also differed in scale, AR showing less attenuation or spurious secondary maxima at anterior sites, consistent with simulations of distributed posterior generators. Posterior task alpha and alpha ERD were positively correlated with overall alpha, but not with net alpha. CSD topographies consistently and appropriately represented posterior EEG alpha for all measures. PMID:26026372

  7. Optimal Measurement Tasks and Their Physical Realizations

    NASA Astrophysics Data System (ADS)

    Yerokhin, Vadim

    This thesis reflects works previously published by the author and materials hitherto unpublished on the subject of quantum information theory. Particularly, results in optimal discrimination, cloning, and separation of quantum states, and their relationships, are discussed. Our interest lies in the scenario where we are given one of two quantum states prepared with a known a-priori probability. We are given full information about the states and are assigned the task of performing an optimal measurement on the incoming state. Given that none of these tasks is in general possible to perform perfectly we must choose a figure of merit to optimize, and as we shall see there is always a trade-off between competing figures of merit, such as the likelihood of getting the desired result versus the quality of the result. For state discrimination the competing figures of merit are the success rate of the measurement, the errors involved, and the inconclusiveness. Similarly increasing the separation between states comes at a cost of less frequent successful applications of the separation protocol. For cloning, aside from successfully producing clones we are also interested in the fidelity of the clones compared to the original state, which is a measure of the quality of the clones. Because all quantum operations obey the same set of conditions for evolution one may expect similar restrictions on disparate measurement strategies, and our work shows a deep connection between all three branches, with cloning and separation asymptotically converging to state discrimination. Via Neumark's theorem, our description of these unitary processes can be implemented using single-photon interferometry with linear optical devices. Amazingly any quantum mechanical evolution may be decomposed as an experiment involving only lasers, beamsplitters, phase-shifters and mirrors. Such readily available tools allow for verification of the aforementioned protocols and we build upon existing results to

  8. Two Approaches to Measuring Task Interdependence in Elementary Schools.

    ERIC Educational Resources Information Center

    Charters, W. W., Jr.

    This report compares two approaches to measuring task interdependence, a theoretically fruitful concept for analyzing an organization's technical system. Task interdependence exists among operating personnel in the degree that task performance of one operative constrains, augments, or otherwise poses contingencies for the performance of another.…

  9. Sentence Repetition: What Does the Task Measure?

    ERIC Educational Resources Information Center

    Polišenská, Kamila; Chiat, Shula; Roy, Penny

    2015-01-01

    Background: Sentence repetition is gaining increasing attention as a source of information about children's sentence-level abilities in clinical assessment, and as a clinical marker of specific language impairment. However, it is widely debated what the task is testing and therefore how informative it is. Aims: (1) To evaluate the effects of…

  10. Utilizing Electroencephalography Measurements for Comparison of Task-Specific Neural Efficiencies: Spatial Intelligence Tasks.

    PubMed

    Call, Benjamin J; Goodridge, Wade; Villanueva, Idalis; Wan, Nicholas; Jordan, Kerry

    2016-01-01

    Spatial intelligence is often linked to success in engineering education and engineering professions. The use of electroencephalography enables comparative calculation of individuals' neural efficiency as they perform successive tasks requiring spatial ability to derive solutions. Neural efficiency here is defined as having less beta activation, and therefore expending fewer neural resources, to perform a task in comparison to other groups or other tasks. For inter-task comparisons of tasks with similar durations, these measurements may enable a comparison of task type difficulty. For intra-participant and inter-participant comparisons, these measurements provide potential insight into the participant's level of spatial ability and different engineering problem solving tasks. Performance on the selected tasks can be analyzed and correlated with beta activities. This work presents a detailed research protocol studying the neural efficiency of students engaged in the solving of typical spatial ability and Statics problems. Students completed problems specific to the Mental Cutting Test (MCT), Purdue Spatial Visualization test of Rotations (PSVT:R), and Statics. While engaged in solving these problems, participants' brain waves were measured with EEG allowing data to be collected regarding alpha and beta brain wave activation and use. The work looks to correlate functional performance on pure spatial tasks with spatially intensive engineering tasks to identify the pathways to successful performance in engineering and the resulting improvements in engineering education that may follow. PMID:27584838

  11. Processing Cantonese lexical tones: Evidence from oddball paradigms.

    PubMed

    Jia, S; Tsang, Y-K; Huang, J; Chen, H-C

    2015-10-01

    Two event-related potential (ERP) experiments were conducted to investigate whether Cantonese lexical tones are processed with general auditory perception mechanisms and/or a special speech module. Two tonal features (f0 direction and f0 height deviation) were manipulated to reflect acoustic processing, and the contrast between syllables and hums was used to reveal the involvement of a speech module. Experiment 1 adopted a passive oddball paradigm to study a relatively early stage of tonal processing. Mismatch negativity (MMN) and novelty P3 (P3a) were modulated by the interaction between tonal feature and stimulus type. Similar interactions were found for N2 and P3 in Experiment 2, where more in-depth tonal processing was examined with an active oddball paradigm. Moreover, detecting tonal deviants of syllables elicited N1 and P2 that were not found in hum detection. Together, these findings suggest that the processing of lexical tone relies on both acoustic and linguistic processes from the early stage. Another noteworthy finding is the absence of brain lateralization in both experiments, which challenges the use of a lateralization pattern as evidence for processing lexical tones through a special speech module.

  12. Response inhibition of cigarette-related cues in male light smokers: behavioral evidence using a two-choice oddball paradigm

    PubMed Central

    Xin, Zhao; Ting, Liu X.; Yi, Zan X.; Li, Dai; Bao, Zhou A.

    2015-01-01

    Behavioral inhibitory control has been shown to play an important role in a variety of addictive behaviors. A number of studies involving the use of Go/NoGo and stop-signal paradigms have shown that smokers have reduced response inhibition for cigarette-related cues. However, it is not known whether male light smokers’ response inhibition for cigarette-related cues is lower than that of non-smokers in the two-choice oddball paradigm. The objective of the current study was to provide further behavioral evidence of male light smokers’ impaired response inhibition for cigarette-related cues, using the two-choice oddball paradigm. Sixty-two male students (31 smokers, 31 non-smokers), who were recruited via an advertisement, took part in this two-choice oddball experiment. Cigarette-related pictures (deviant stimuli) and pictures unrelated to cigarettes (standard stimuli) were used. Response inhibition for cigarette-related cues was measured by comparing accuracy (ACC) and reaction time (RT) for deviant and standard stimuli in the two groups of subjects. An analysis of variance (ANOVA) showed that in all the participants, ACC was significantly lower for deviant stimuli than for standard stimuli. For deviant stimuli, the RTs were significantly longer for male light smokers than for male non-smokers; however, there was no significant difference in RTs for standard stimuli. Compared to male non-smokers, male light smokers seem to have a reduced ability to inhibit responses to cigarette-related cues. PMID:26528200

  13. Target and Non-Target Processing during Oddball and Cyberball: A Comparative Event-Related Potential Study

    PubMed Central

    Weschke, Sarah; Niedeggen, Michael

    2016-01-01

    The phenomenon of social exclusion can be investigated by using a virtual ball-tossing game called Cyberball. In neuroimaging studies, structures have been identified which are activated during social exclusion. But to date the underlying mechanisms are not fully disclosed. In previous electrophysiological studies it was shown that the P3 complex is sensitive to exclusion manipulations in the Cyberball paradigm and that there is a correlation between P3 amplitude and self-reported social pain. Since this posterior event-related potential (ERP) was widely investigated using the oddball paradigm, we directly compared the ERP effects elicited by the target (Cyberball: “ball possession”) and non-target (Cyberball: “ball possession of a co-player) events in both paradigms. Analyses mainly focused on the effect of altered stimulus probabilities of the target and non-target events between two consecutive blocks of the tasks. In the first block, the probability of the target and non-target event was 33% (Cyberball: inclusion), in the second block target probability was reduced to 17%, and accordingly, non-target probability was increased to 66% (Cyberball: exclusion). Our results indicate that ERP amplitude differences between inclusion and exclusion are comparable to ERP amplitude effects in a visual oddball task. We therefore suggest that ERP effects–especially in the P3 range–in the Oddball and Cyberball paradigm rely on similar mechanisms, namely the probability of target and non-target events. Since the simulation of social exclusion (Cyberball) did not trigger a unique ERP response, the idea of an exclusion-specific neural alarm system is not supported. The limitations of an ERP-based approach will be discussed. PMID:27100787

  14. Target and Non-Target Processing during Oddball and Cyberball: A Comparative Event-Related Potential Study.

    PubMed

    Weschke, Sarah; Niedeggen, Michael

    2016-01-01

    The phenomenon of social exclusion can be investigated by using a virtual ball-tossing game called Cyberball. In neuroimaging studies, structures have been identified which are activated during social exclusion. But to date the underlying mechanisms are not fully disclosed. In previous electrophysiological studies it was shown that the P3 complex is sensitive to exclusion manipulations in the Cyberball paradigm and that there is a correlation between P3 amplitude and self-reported social pain. Since this posterior event-related potential (ERP) was widely investigated using the oddball paradigm, we directly compared the ERP effects elicited by the target (Cyberball: "ball possession") and non-target (Cyberball: "ball possession of a co-player) events in both paradigms. Analyses mainly focused on the effect of altered stimulus probabilities of the target and non-target events between two consecutive blocks of the tasks. In the first block, the probability of the target and non-target event was 33% (Cyberball: inclusion), in the second block target probability was reduced to 17%, and accordingly, non-target probability was increased to 66% (Cyberball: exclusion). Our results indicate that ERP amplitude differences between inclusion and exclusion are comparable to ERP amplitude effects in a visual oddball task. We therefore suggest that ERP effects--especially in the P3 range--in the Oddball and Cyberball paradigm rely on similar mechanisms, namely the probability of target and non-target events. Since the simulation of social exclusion (Cyberball) did not trigger a unique ERP response, the idea of an exclusion-specific neural alarm system is not supported. The limitations of an ERP-based approach will be discussed.

  15. 'What's in a name?' 'No more than when it's mine own'. Evidence from auditory oddball distraction.

    PubMed

    Ljungberg, Jessica K; Parmentier, Fabrice B R; Jones, Dylan M; Marsja, Erik; Neely, Gregory

    2014-07-01

    Research of the distractor value of hearing the own name has shown that this self-referring stimulus captures attention in an involuntary fashion and create distraction. The behavioral studies are few and the outcomes are not always clear cut. In this study the distraction by own name compared to a control name was investigated by using a cross-modal oddball task in two experiments. In the first experiment, thirty-nine participants were conducting a computerized categorization task while exposed to, to-be ignored own and matched control names (controlling for familiarity, gender and number of syllables) as unexpected auditory deviant stimulus (12.5% trials for each name category) and a sine wave tone as a standard stimulus (75% of the trials). In the second experiment, another group of thirty-nine participants completed the same task but with the additional deviant stimulus of an irrelevant word added (10% trials for each deviant type and 70% trials with the standard stimulus). Results showed deviant distraction by exposure to both the irrelevant word, own and the control name compared to the standard tone but no differences were found showing that the own name captured attention and distracted the participants more than an irrelevant word or a control name. The results elucidate the role of the own name as a potent auditory distractor and possible limitations with its theoretical significance for general theories of attention are discussed.

  16. Report of the Task Force on Institutional Effectiveness Measures.

    ERIC Educational Resources Information Center

    Arizona State Board of Directors for Community Colleges, Phoenix.

    The Task Force on Institutional Effectiveness Measures was formed by the State Board of Directors for Community Colleges of Arizona to develop a statewide plan for systematically demonstrating the degree to which community colleges accomplish their diverse missions. Two subgroups were formed in the Task Force on transfer and college programs and…

  17. An objective index of individual face discrimination in the right occipito-temporal cortex by means of fast periodic oddball stimulation.

    PubMed

    Liu-Shuang, Joan; Norcia, Anthony M; Rossion, Bruno

    2014-01-01

    We introduce an approach based on fast periodic oddball stimulation that provides objective, high signal-to-noise ratio (SNR), and behavior-free measures of the human brain's discriminative response to complex visual patterns. High-density electroencephalogram (EEG) was recorded for human observers presented with 60s sequences containing a base-face (A) sinusoidally contrast-modulated at a frequency of 5.88 Hz (F), with face size varying every cycle. Different oddball-faces (B, C, D...) were introduced at fixed intervals (every 4 stimuli = F/5 = 1.18 Hz: AAAABAAAACAAAAD...). Individual face discrimination was indexed by responses at this 1.18 Hz oddball frequency. Following only 4 min of recording, significant responses emerged at exactly 1.18 Hz and its harmonics (e.g., 2F/5 = 2.35 Hz, 3F/5 = 3.53 Hz...), with up to a 300% signal increase over the right occipito-temporal cortex. This response was present in all participants, for both color and greyscale faces, providing a robust implicit neural measure of individual face discrimination. Face inversion or contrast-reversal did not affect the basic 5.88 Hz periodic response over medial occipital channels. However, these manipulations substantially reduced the 1.18 Hz oddball discrimination response over the right occipito-temporal region, indicating that this response reflects high-level processes that are partly face-specific. These observations indicate that fast periodic oddball stimulation can be used to rapidly and objectively characterize the discrimination of visual patterns and may become invaluable in characterizing this process in typical adult, developmental, and neuropsychological patient populations.

  18. Reliability of Composite Task Measurements of Holistic Face Processing

    PubMed Central

    Ross, David A.; Richler, Jennifer J.; Gauthier, Isabel

    2014-01-01

    There is growing interest in the study of individual differences in face recognition, including one of its hallmarks, holistic processing, which can be defined as a failure of selective attention to parts. These efforts demand that researchers be aware of, and try to maximize, the reliability of their measurements. Here we report on the reliability of measurements using the composite task (complete design), a measure of holistic processing that has been shown to have relatively good validity. Several studies have used the composite task to investigate individual differences, yet only one study has discussed its reliability. We investigate the reliability of composite task measurements in eight datasets from five different samples of subjects. In general, we found reliability to be fairly low but there was substantial variability across experiments. Researchers should keep in mind that reliability is a property of measurements, not a task, and the ways in which measurements in this task may be improved, before embarking on individual differences research. PMID:24961957

  19. One-year developmental stability and covariance among oddball, novelty, go/no-go, and flanker event-related potentials in adolescence: A monozygotic twin study.

    PubMed

    Burwell, Scott J; Malone, Stephen M; Iacono, William G

    2016-07-01

    ERP measures may index genetic risk for psychopathology before disorder onset in adolescence, but little is known about their developmental rank-order stability during this period of significant brain maturation. We studied ERP stability in 48 pairs of identical twins (age 14-16 years) tested 1 year apart. Trial-averaged voltage waveforms were extracted from electroencephalographic recordings from oddball/novelty, go/no-go, and flanker tasks, and 16 amplitude measures were examined. Members of twin pairs were highly similar, whether based on ERP amplitude measures (intraclass correlation [ICC] median = .64, range = .44-.86) or three factor scores (all ICCs ≥ .69) derived from them. Stability was high overall, with 69% of the 16 individual measures generating stability coefficients exceeding .70 and all factor scores showing stability above .75. Measures from 10 difference waveforms calculated from paired conditions within tasks were also examined, and were associated with lower twin similarity (ICC median = .52, .38-.64) and developmental stability (only 30% exceeding .70). In a supplemental analysis, we found significant developmental stability for error-related negativity (range = .45-.55) and positivity (.56-.70) measures when average waveforms were based on one or more trials, and that these values were equivalent to those derived from averages using the current field recommendation, which requires six or more trials. Overall, we conclude that the studied brain measures are largely stable over 1 year of mid- to late adolescence, likely reflecting familial etiologic influences on brain functions pertaining to cognitive control and salience recognition.

  20. Task switching and the measurement of "switch costs".

    PubMed

    Wylie, G; Allport, A

    2000-01-01

    The measurement of "switch costs" is held to be of interest because, as is widely believed, they may reflect the control processes that are engaged when subjects switch between two (or more) competing tasks. [In task-switching experiments, the reaction time (RT) switch cost is typically measured as the difference in RT between switch and non-switch (repeat) trials.] In this report we focus on the RT switch costs that remain even after the subject has had some time to prepare for the shift of task, when the switch cost may be approximately asymptotic (so-called residual switch costs). Three experiments are presented. All three experiments used Stroop colour/word, and neutral stimuli. Participants performed the two tasks of word-reading and colour-naming in a regular, double alternation, using the "alternating runs" paradigm (R. D. Rogers & S. Monsell, 1995). The experiments were designed to test the hypothesis that RT switch costs depend on a form of proactive interference (PI) arising from the performance of a prior, competing task. A. Allport, E. A. Styles and S. Hsieh (1994) suggested that these PI effects resulted from "task-set inertia", that is, the persisting activation-suppression of competing task-sets, or competing task-processing pathways. The results confirmed the existence of long-lasting PI from the competing task as a major contributor to switch costs. Non-switch trials, used as the baseline in the measurement of switch costs, were also shown to be strongly affected by similar PI effects. However, task-set inertia was not sufficient to account for these results. The results appeared inconsistent also with all other previous models of task switching. A new hypothesis to explain these between-task interference effects was developed, based on the stimulus-triggered retrieval of competing stimulus-response (S-R) associations, acquired (or strengthened) in earlier trials. Consistent with this retrieval hypothesis, switch costs were shown to depend

  1. Pain-reduction strategies in hypnotic context and hypnosis: ERPs and SCRs during a secondary auditory task.

    PubMed

    De Pascalis, Vilfredo; Bellusci, Anna; Gallo, Carlo; Magurano, Maria Rosaria; Chen, Andrew C N

    2004-10-01

    Pain-rating scores were obtained from 10 high, 10 medium, and 10 low hypnotizable subjects who were holding a painful cold bottle in their left hands and were exposed to pain reduction treatments while they were performing a secondary oddball task. All subjects received suggestions of dissociative imagery and focused analgesia as cognitive strategies for pain reduction. The following measures were obtained for tone targets of the auditory oddball task: (a) reaction time; (b) P300 peak amplitude of the event-related potentials; (c) skin conductance levels and skin conductance responses. Focused analgesia produced the most pain reduction in high, but not medium or low, hypnotizable subjects who showed shorter reaction times, higher central and parietal P300 peaks, and higher skin conductance responses. These findings were discussed vis-a-vis the dissociated-control model assuming that capacity demands of hypnotic suggestion are low. PMID:15590503

  2. Proportional Reasoning Tasks as a Measure of Formal Reasoning Ability.

    ERIC Educational Resources Information Center

    Shemesh, Michal

    A nonequivalent control group design study, with a math unit on ratio and proportion as the treatment, was conducted to examine the validity of some written tasks as a measure of formal reasoning. Subjects in the study were 68 fifth grade students who enrolled in two classes in a small urban school. The experimental group learned a 12-lesson math…

  3. Measurement of operator workload in an information processing task

    NASA Technical Reports Server (NTRS)

    Jenney, L. L.; Older, H. J.; Cameron, B. J.

    1972-01-01

    This was an experimental study to develop an improved methodology for measuring workload in an information processing task and to assess the effects of shift length and communication density (rate of information flow) on the ability to process and classify verbal messages. Each of twelve subjects was exposed to combinations of three shift lengths and two communication densities in a counterbalanced, repeated measurements experimental design. Results indicated no systematic variation in task performance measures or in other dependent measures as a function of shift length or communication density. This is attributed to the absence of a secondary loading task, an insufficiently taxing work schedule, and the lack of psychological stress. Subjective magnitude estimates of workload showed fatigue (and to a lesser degree, tension) to be a power function of shift length. Estimates of task difficulty and fatigue were initially lower but increased more sharply over time under low density than under high density conditions. An interpretation of findings and recommedations for furture research are included. This research has major implications to human workload problems in information processing of air traffic control verbal data.

  4. Experimental measurements of motion cue effects on STOL approach tasks

    NASA Technical Reports Server (NTRS)

    Ringland, R. F.; Stapleford, R. L.

    1972-01-01

    An experimental program to investigate the effects of motion cues on STOL approach is presented. The simulator used was the Six-Degrees-of-Freedom Motion Simulator (S.01) at Ames Research Center of NASA which has ?2.7 m travel longitudinally and laterally and ?2.5 m travel vertically. Three major experiments, characterized as tracking tasks, were conducted under fixed and moving base conditions: (1) A simulated IFR approach of the Augmentor Wing Jet STOL Research Aircraft (AWJSRA), (2) a simulated VFR task with the same aircraft, and (3) a single-axis task having only linear acceleration as the motion cue. Tracking performance was measured in terms of the variances of several motion variables, pilot vehicle describing functions, and pilot commentary.

  5. Self-measuring Similarity for Multi-task Gaussian Process

    NASA Astrophysics Data System (ADS)

    Hayashi, Kohei; Takenouchi, Takashi; Tomioka, Ryota; Kashima, Hisashi

    Multi-task learning aims at transferring knowledge between similar tasks. The multi-task Gaussian process framework of Bonilla et al. models (incomplete) responses of C data points for R tasks (e.g., the responses are given by R × C matrix) by a Gaussian process; the covariance function is defined as the product of a covariance function on input-dependent features and the inter-task covariance matrix (which is empirically estimated as a model parameter). We extend this framework by incorporating a novel similarity measurement, which allows for the representation of much more complex data structures. The proposed framework also enables us to exploit additional information (e.g., the input-dependent features) by constructing the covariance matrices with combining them on the covariance function. We also derive an efficient learning algorithm to make prediction by using an iterative method. Finally, we apply our model to a real data set of recommender systems and show that the proposed method achieves the best prediction accuracy on the data set.

  6. Event-related desynchronization of frontal-midline theta rhythm during preconscious auditory oddball processing.

    PubMed

    Kawamata, Masaru; Kirino, Eiji; Inoue, Reiichi; Arai, Heii

    2007-10-01

    The goal of this study was to explore the frontal-midline theta rhythm (Fm theta) generation mechanism employing event-related desynchronization/synchronization (ERD/ERS) analysis in relation to task-irrelevant external stimuli. A dual paradigm was employed: a videogame and the simultaneous presentation of passive auditory oddball stimuli. We analyzed the data concerning ERD/ERS using both Fast Fourier Transformation (FFT) and wavelet transform (WT). In the FFT data, during the periods with appearance of Fm theta, apparent ERD of the theta band was observed at Fz and Cz. ERD when Fm theta was present was much more prominent than when Fm theta was absent. In the WT data, as in the FFT data, ERD was seen again, but in this case the ERD was preceded by ERS during both the periods with and without Fm theta. Furthermore, the WT analysis indicated that ERD was followed by ERS during the periods without Fm theta. However, during Fm theta, no apparent ERS following ERD was seen. In our study, Fm theta was desynchronized by the auditory stimuli that were independent of the video game task used to evoke the Fm theta. The ERD of Fm theta might be reflecting the mechanism of "positive suppression" to process external auditory stimuli automatically and preventing attentional resources from being unnecessarily allocated to those stimuli. Another possibility is that Fm theta induced by our dual paradigm may reflect information processing modeled by multi-item working memory requirements for playing the videogame and the simultaneous auditory processing using a memory trace. ERS in the WT data without Fm theta might indicate further processing of the auditory information free from "positive suppression" control reflected by Fm theta. PMID:17993201

  7. Breast Cancer EDGE Task Force Outcomes: Clinical Measures of Pain

    PubMed Central

    Harrington, Shana; Gilchrist, Laura; Sander, Antoinette

    2014-01-01

    Background Pain is one of the most commonly reported impairments after breast cancer treatment affecting anywhere from 16-73% of breast cancer survivors Despite the high reported incidence of pain from cancer and its treatments, the ability to evaluate cancer pain continues to be difficult due to the complexity of the disease and the subjective experience of pain. The Oncology Section Breast Cancer EDGE Task Force was created to evaluate the evidence behind clinical outcome measures of pain in women diagnosed with breast cancer. Methods The authors systematically reviewed the literature for pain outcome measures published in the research involving women diagnosed with breast cancer. The goal was to examine the reported psychometric properties that are reported in the literature in order to determine clinical utility. Results Visual Analog Scale, Numeric Rating Scale, Pressure Pain Threshold, McGill Pain Questionnaire, McGill Pain Questionnaire – Short Form, Brief Pain Inventory and Brief Pain Inventory – Short Form were highly recommended by the Task Force. The Task Force was unable to recommend two measures for use in the breast cancer population at the present time. Conclusions A variety of outcome measures were used to measure pain in women diagnosed with breast cancer. When assessing pain in women with breast cancer, researchers and clinicians need to determine whether a unidimensional or multidimensional tool is most appropriate as well as whether the tool has strong psychometric properties. PMID:25346950

  8. Metrics and Measures for Intelligence Analysis Task Difficulty

    SciTech Connect

    Greitzer, Frank L.; Allwein, Kelcy M.

    2005-05-02

    Recent workshops and conferences supporting the intelligence community (IC) have highlighted the need to characterize the difficulty or complexity of intelligence analysis (IA) tasks in order to facilitate assessments of the impact or effectiveness of IA tools that are being considered for introduction into the IC. Some fundamental issues are: (a) how to employ rigorous methodologies in evaluating tools, given a host of problems such as controlling for task difficulty, effects of time or learning, small-sample size limitations; (b) how to measure the difficulty/complexity of IA tasks in order to establish valid experimental/quasi-experimental designs aimed to support evaluation of tools; and (c) development of more rigorous (summative), performance-based measures of human performance during the conduct of IA tasks, beyond the more traditional reliance on formative assessments (e.g., subjective ratings). Invited discussants will be asked to comment on one or more of these issues, with the aim of bringing the most salient issues and research needs into focus

  9. Phase Measurement of Galvanneal Task JPL Task Order Number: RF-152 Amendment Number: 543

    SciTech Connect

    Lynn Lowry; Beverly Tai

    1995-03-01

    The objective of this task was to demonstrate an x-ray fluorescence (XRF) technique which would measure the phase composition of galvanneal coatings of sheet steel rapidly and non-destructively with an accuracy of 0.5%. This data acquisition and analysis method would be implemented as an on-line process control input. The AISI sample matrix evaluated for this study is shown in Appendix I. The Jet Propulsion Laboratory (JPL) and Data Measurement Corporation (DMC) measured iron and zinc XRF responses from these samples. In addition, JPL performed metallograph, x-ray diffraction (XRD), and transmission electron microscopy (TEM) to characterize the samples' galvanneal phase morphology. This data was correlated with the XRF experimental results and then compared to phase composition models, which were generated using a Fundamental Parameters Method (FPM) approach.

  10. Transferring Cognitive Tasks Between Brain Imaging Modalities: Implications for Task Design and Results Interpretation in fMRI Studies

    PubMed Central

    Warbrick, Tracy; Reske, Martina; Shah, N. Jon

    2014-01-01

    As cognitive neuroscience methods develop, established experimental tasks are used with emerging brain imaging modalities. Here transferring a paradigm (the visual oddball task) with a long history of behavioral and electroencephalography (EEG) experiments to a functional magnetic resonance imaging (fMRI) experiment is considered. The aims of this paper are to briefly describe fMRI and when its use is appropriate in cognitive neuroscience; illustrate how task design can influence the results of an fMRI experiment, particularly when that task is borrowed from another imaging modality; explain the practical aspects of performing an fMRI experiment. It is demonstrated that manipulating the task demands in the visual oddball task results in different patterns of blood oxygen level dependent (BOLD) activation. The nature of the fMRI BOLD measure means that many brain regions are found to be active in a particular task. Determining the functions of these areas of activation is very much dependent on task design and analysis. The complex nature of many fMRI tasks means that the details of the task and its requirements need careful consideration when interpreting data. The data show that this is particularly important in those tasks relying on a motor response as well as cognitive elements and that covert and overt responses should be considered where possible. Furthermore, the data show that transferring an EEG paradigm to an fMRI experiment needs careful consideration and it cannot be assumed that the same paradigm will work equally well across imaging modalities. It is therefore recommended that the design of an fMRI study is pilot tested behaviorally to establish the effects of interest and then pilot tested in the fMRI environment to ensure appropriate design, implementation and analysis for the effects of interest. PMID:25285453

  11. On the importance of Task 1 and error performance measures in PRP dual-task studies

    PubMed Central

    Strobach, Tilo; Schütz, Anja; Schubert, Torsten

    2015-01-01

    The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects. PMID:25904890

  12. First love does not die: a sustaining primacy effect on ERP components in an oddball paradigm.

    PubMed

    Kotchoubey, Boris

    2014-03-27

    Both primacy and frequency factors belong to very powerful regulators of human cognition and behavior, but their relationship is only scarcely investigated. This study aimed to investigate the interplay of primacy and frequency effects on behavioral and electrophysiological (event-related potential, ERP) measures using an oddball paradigm. In each experiment 234 frequent (standard) and 66 rare (deviant) harmonic tones were presented. Participants either responded to stimuli with a button press (motor experiment) or counted the rare stimulus (counting experiment). Each experiment entailed two counterbalanced conditions. In the "classical" condition both standards and deviants were equally distributed across the presentation series, while in the "primacy" condition more deviants were concentrated at the beginning of the series. In the motor experiment no differences between the two conditions were obtained at the behavioral level, but the amplitude of N2 to deviants was significantly larger in the classical than primacy condition, and the same trend was obtained for the P3 component at lateral posterior sites. In the counting experiment both N2b and P3 effects were strongly reduced in the primacy condition as compared with the classical condition. Therefore, stimuli that were frequently presented in the first stimulation run were subsequently processed as "less rare", although in fact they were even rarer than in the control condition. The data indicate that the initial pattern of stimulation can substantially affect the frequency effect during the processing of subsequent stimuli.

  13. Duration-based measures of preference for vocational tasks.

    PubMed

    Worsdell, April S; Iwata, Brian A; Wallace, Michele D

    2002-01-01

    We compared results from two preference assessments with data on extended performance of vocational tasks by 4 participants with developmental disabilities. All participants engaged in one task exclusively when seven tasks were available concurrently during a 5-min multiple-stimulus assessment. By contrast, all participants exhibited high levels of engagement in most tasks when the tasks were presented singly for 5 min, and these data showed a high degree of correspondence with those obtained during extended (60-min) vocational assessments.

  14. Lifespan Differences in Nonlinear Dynamics during Rest and Auditory Oddball Performance

    ERIC Educational Resources Information Center

    Muller, Viktor; Lindenberger, Ulman

    2012-01-01

    Electroencephalographic recordings (EEG) were used to assess age-associated differences in nonlinear brain dynamics during both rest and auditory oddball performance in children aged 9.0-12.8 years, younger adults, and older adults. We computed nonlinear coupling dynamics and dimensional complexity, and also determined spectral alpha power as an…

  15. Investigating a Novel Measure of Brain Networking Following Sports Concussion.

    PubMed

    Broglio, S P; Rettmann, A; Greer, J; Brimacombe, S; Moore, B; Narisetty, N; He, X; Eckner, J

    2016-08-01

    Clinicians managing sports-related concussions are left to their clinical judgment in making diagnoses and return-to-play decisions. This study was designed to evaluate the utility of a novel measure of functional brain networking for concussion management. 24 athletes with acutely diagnosed concussion and 21 control participants were evaluated in a research laboratory. At each of the 4 post-injury time points, participants completed the Axon assessment of neurocognitive function, a self-report symptom inventory, and the auditory oddball and go/no-go tasks while electroencephalogram (EEG) readings were recorded. Brain Network Activation (BNA) scores were calculated from EEG data related to the auditory oddball and go/no-go tasks. BNA scores were unable to differentiate between the concussed and control groups or by self-report symptom severity. These findings conflict with previous work implementing electrophysiological assessments in concussed athletes, suggesting that BNA requires additional investigation and refinement before clinical implementation. PMID:27286176

  16. Neuropharmacological effect of atomoxetine on attention network in children with attention deficit hyperactivity disorder during oddball paradigms as assessed using functional near-infrared spectroscopy

    PubMed Central

    Nagashima, Masako; Monden, Yukifumi; Dan, Ippeita; Dan, Haruka; Mizutani, Tsutomu; Tsuzuki, Daisuke; Kyutoku, Yasushi; Gunji, Yuji; Hirano, Daisuke; Taniguchi, Takamichi; Shimoizumi, Hideo; Momoi, Mariko Y.; Yamagata, Takanori; Watanabe, Eiju

    2014-01-01

    Abstract. The current study aimed to explore the neural substrate for atomoxetine effects on attentional control in school-aged children with attention deficit hyperactivity disorder (ADHD) using functional near-infrared spectroscopy (fNIRS), which can be applied to young children with ADHD more easily than conventional neuroimaging modalities. Using fNIRS, we monitored the oxy-hemoglobin signal changes of 15 ADHD children (6 to 14 years old) performing an oddball task before and 1.5 h after atomoxetine or placebo administration, in a randomized, double-blind, placebo-controlled, crossover design. Fifteen age-, gender-, and intelligence quotient-matched normal controls without atomoxetine administration were also monitored. In the control subjects, the oddball task recruited the right prefrontal and inferior parietal cortices. The right prefrontal and parietal activation was normalized after atomoxetine administration in ADHD children. This was in contrast to our previous study using a similar protocol showing methylphenidate-induced normalization of only the right prefrontal function. fNIRS allows the detection of differential neuropharmacological profiles of both substances in the attentional network: the neuropharmacological effects of atomoxetine to upregulate the noradrenergic system reflected in the right prefrontal and inferior parietal activations and those of methylphenidate to upregulate the dopamine system reflected in the prefrontal cortex activation. PMID:26157979

  17. Neuropharmacological effect of methylphenidate on attention network in children with attention deficit hyperactivity disorder during oddball paradigms as assessed using functional near-infrared spectroscopy.

    PubMed

    Nagashima, Masako; Monden, Yukifumi; Dan, Ippeita; Dan, Haruka; Tsuzuki, Daisuke; Mizutani, Tsutomu; Kyutoku, Yasushi; Gunji, Yuji; Momoi, Mariko Y; Watanabe, Eiju; Yamagata, Takanori

    2014-07-01

    The current study aimed to explore the neural substrate for methylphenidate effects on attentional control in school-aged children with attention deficit hyperactivity disorder (ADHD) using functional near-infrared spectroscopy (fNIRS), which can be applied to young children with ADHD more easily than conventional neuroimaging modalities. Using fNIRS, we monitored the oxy-hemoglobin signal changes of 22 ADHD children (6 to 14 years old) performing an oddball task before and 1.5 h after methylphenidate or placebo administration, in a randomized, double-blind, placebo-controlled, crossover design. Twenty-two age- and gender-matched normal controls without methylphenidate administration were also monitored. In the control subjects, the oddball task recruited the right prefrontal and inferior parietal cortices, and this activation was absent in premedicated ADHD children. The reduced right prefrontal activation was normalized after methylphenidate but not placebo administration in ADHD children. These results are consistent with the neuropharmacological effects of methylphenidate to upregulate the dopamine system in the prefrontal cortex innervating from the ventral tegmentum (mesocortical pathway), but not the noradrenergic system from the parietal cortex to the locus coeruleus. Thus, right prefrontal activation would serve as an objective neurofunctional biomarker to indicate the effectiveness of methylphenidate on ADHD children in attentional control. fNIRS monitoring enhances early clinical diagnosis and the treatment of ADHD children, especially those with an inattention phenotype. PMID:26157971

  18. Cortical potentials in an auditory oddball task reflect individual differences in working memory capacity

    PubMed Central

    Yurgil, Kate A.; Golob, Edward J.

    2014-01-01

    This study determined whether auditory cortical responses associated with mechanisms of attention vary with individual differences in working memory capacity (WMC) and perceptual load. The operation span test defined subjects with low vs. high WMC, who then discriminated target/nontarget tones while EEG was recorded. Infrequent white noise distracters were presented at midline or ±90° locations, and perceptual load was manipulated by varying nontarget frequency. Amplitude of the N100 to distracters was negatively correlated with WMC. Relative to targets, only high WMC subjects showed attenuated N100 amplitudes to nontargets. In the higher WMC group, increased perceptual load was associated with decreased P3a amplitudes to distracters and longer-lasting negative slow wave to nontargets. Results show that auditory cortical processing is associated with multiple facets of attention control related to WMC and possibly higher-level cognition. PMID:24016201

  19. Conjunctive Continuous Performance Task (CCPT)--A Pure Measure of Sustained Attention

    ERIC Educational Resources Information Center

    Shalev, Lilach; Ben-Simon, Anat; Mevorach, Carmel; Cohen, Yoav; Tsal, Yehoshua

    2011-01-01

    Among the large variety of attentional tasks that have been used to study sustained attention, the Continuous Performance Task (CPT) is perhaps the most widely used. Despite substantial differences in task characteristics and demands, all CPT paradigms have been referred to as measures of sustained attention. In the present study we introduce a…

  20. Measuring Children's Age Stereotyping Using a Modified Piagetian Conservation Task

    ERIC Educational Resources Information Center

    Kwong See, Sheree T.; Rasmussen, Carmen; Pertman, S. Quinn

    2012-01-01

    We examined five-year-old-children's age stereotyping using a modified Piagetian conservation task. Children were asked if two lines of objects were the "same" after one line had been made longer (transformed). A conversational account posits that children's answers reflect assumptions about the asker's motivation for the question (Schwarz, 1996).…

  1. Measuring Attention in Rodents: Comparison of a Modified Signal Detection Task and the 5-Choice Serial Reaction Time Task.

    PubMed

    Turner, Karly M; Peak, James; Burne, Thomas H J

    2015-01-01

    Neuropsychiatric research has utilized cognitive testing in rodents to improve our understanding of cognitive deficits and for preclinical drug development. However, more sophisticated cognitive tasks have not been as widely exploited due to low throughput and the extensive training time required. We developed a modified signal detection task (SDT) based on the growing body of literature aimed at improving cognitive testing in rodents. This study directly compares performance on the modified SDT with a traditional test for measuring attention, the 5-choice serial reaction time task (5CSRTT). Adult male Sprague-Dawley rats were trained on either the 5CSRTT or the SDT. Briefly, the 5CSRTT required rodents to pay attention to a spatial array of five apertures and respond with a nose poke when an aperture was illuminated. The SDT required the rat to attend to a light panel and respond either left or right to indicate the presence of a signal. In addition, modifications were made to the reward delivery, timing, control of body positioning, and the self-initiation of trials. It was found that less training time was required for the SDT, with both sessions to criteria and daily session duration significantly reduced. Rats performed with a high level of accuracy (>87%) on both tasks, however omissions were far more frequent on the 5CSRTT. The signal duration was reduced on both tasks as a manipulation of task difficulty relevant to attention and a similar pattern of decreasing accuracy was observed on both tasks. These results demonstrate some of the advantages of the SDT over the traditional 5CSRTT as being higher throughput with reduced training time, fewer omission responses and their body position was controlled at stimulus onset. In addition, rats performing the SDT had comparable high levels of accuracy. These results highlight the differences and similarities between the 5CSRTT and a modified SDT as tools for assessing attention in preclinical animal models. PMID

  2. A functional MRI study of visual oddball: evidence for frontoparietal dysfunction in subjects at risk for alcoholism.

    PubMed

    Rangaswamy, Madhavi; Porjesz, Bernice; Ardekani, Babak A; Choi, Steven J; Tanabe, Jody L; Lim, Kelvin O; Begleiter, Henri

    2004-01-01

    Attending to rare stimuli interspersed among repetitive frequent stimuli produces a positive scalp potential at 300 to 600 ms after the target stimulus onset; this potential is known as the P300 wave. Although there is clear evidence of low visual P300 in subjects at high risk (HR) for developing alcoholism, the functional neuroanatomical correlates have not been studied. Functional and high-resolution anatomical magnetic resonance images were collected during the performance of a visual oddball task, from six control (low risk-LR) subjects with high P300s and eight HR subjects with low P300s. All the HR subjects were offspring of male alcoholics. The data were analyzed using a randomization-based statistical method that accounts for multiple comparisons, requires no assumptions about the noise structure of the data, and does not require spatial or temporal smoothing. Target counts showed that all subjects performed the task comparably. Analysis of the functional magnetic resonance imaging (fMRI) data revealed two areas with significantly lower activation in the HR group when compared to the LR group: the bilateral inferior parietal lobule (BA 40), and the bilateral inferior frontal gyrus (BA 44). Inferior parietal lobule showed significantly lower activation in the HR group in contrast to the LR group, and inferior frontal gyrus was not activated in the HR group but was only activated in the LR group. This finding indicates that a dysfunctional frontoparietal circuit may underlie the low P300 responses seen in HR subjects. This perhaps implies a deficiency in the rehearsal component of the working memory system.

  3. Consistency and cost of dual-task gait balance measure in healthy adolescents and young adults.

    PubMed

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

    2016-09-01

    Matched control data are commonly used to examine recovery from concussion. Limited data exist, however, examining dual-task gait data consistency collected over time in healthy individuals. The study purposes were to: 1) assess the consistency of single-task and dual-task gait balance control measures, 2) determine the minimal detectable change (MDC) of gait balance control measures, and 3) examine the extent to which age and task complexity affect dual-task walking costs in healthy adolescents and young adults. Twenty-four adolescent (mean age=15.5±1.1years) and 21 young adult (mean age=21.2±4.5years) healthy participants completed 5 testing sessions across a two-month period, which involved analyses of gait balance control and temporal-distance variables during single-task and dual-task walking conditions in a motion analysis laboratory. Cronbach's α and MDCs were used to determine the consistency of the gait balance control variables and the smallest amount of change required to distinguish true performance from change due to the performance/measurement variability, respectively. Dual-task costs were evaluated to determine the effect of task complexity and age across time using 3-way ANOVAs. Good to excellent test-retest consistency was found for all single-task and dual-task walking (Cronbach's α range: 0.764-0.970), with a center-of-mass medial-lateral displacement MDC range of 0.835-0.948cm. Greater frontal plane dual-task costs were observed during more complex secondary tasks (p<0.001). The results revealed good-excellent consistency across testing sessions for all variables and indicated dual-task costs are affected by task complexity. Thus, healthy controls can be effective comparators when assessing injured subjects.

  4. Comparison of Psychophysiological and Dual-Task Measures of Listening Effort

    ERIC Educational Resources Information Center

    Seeman, Scott; Sims, Rebecca

    2015-01-01

    Purpose: We wished to make a comparison of psychophysiological measures of listening effort with subjective and dual-task measures of listening effort for a diotic-dichotic-digits and a sentences-in-noise task. Method: Three groups of young adults (18-38 years old) with normal hearing participated in three experiments: two psychophysiological…

  5. Task Listings Resulting from the Vocational Competency Measures Project. Memorandum Report.

    ERIC Educational Resources Information Center

    American Institutes for Research in the Behavioral Sciences, Palo Alto, CA.

    This memorandum report consists of 14 task listings resulting from the Vocational Competency Measures Project. (The Vocational Competency Measures Project was a test development project that involved the writing and verification of task listings for 14 vocational occupational areas through over 225 interviews conducted in 27 states.) Provided in…

  6. Transient tasks and enduring emotions: the impacts of affective content, task relevance, and picture duration on the sustained late positive potential.

    PubMed

    Gable, Philip A; Adams, David L; Proudfit, Greg Hajcak

    2015-03-01

    The present experiments were designed to examine the influences of picture duration, task relevance, and affective content on neural measures of sustained engagement, as indexed by the late positive potential (LPP). Much prior work has shown that the event-related potential in and around the P3-here referred to as the early LPP-is modulated by affective content, nonaffective task relevance, and stimulus duration. However, later portions of the LPP (>1,000 ms) may represent either a return to baseline or a continued physiological process related to motivational engagement. In the present experiments, we tested whether modulation of the later LPP depends on varying motivational engagement using stimulus duration, affective content, and task relevance. The results of Experiment 1 revealed that stimulus duration modulates the sustained LPP (i.e., 1,000-2,000 ms) in response to affective, but not task-relevant, stimuli from a modified counting oddball task. The results of Experiment 2 revealed that the sustained increase in the LPP is sensitive to both emotional content and task relevance when the task requires sustained engagement with target stimuli (e.g., determining the duration of stimulus presentation). The impacts of emotional content and task relevance had additive effects on the later portion of the LPP. In sum, both emotional content and task relevance can result in a protracted increase in the later LPP. These data suggest that affective content automatically sustains engagement, whereas task relevance only prolongs engagement when it is necessary for task completion.

  7. Measuring Delay Discounting in Humans Using an Adjusting Amount Task.

    PubMed

    Frye, Charles C J; Galizio, Ann; Friedel, Jonathan E; DeHart, W Brady; Odum, Amy L

    2016-01-09

    Delay discounting refers to a decline in the value of a reward when it is delayed relative to when it is immediately available. Delay discounting tasks are used to identify indifference points, which reflect equal preference for two dichotomous reward alternatives differing in both delay and magnitude. Indifference points are key to assessing the shape of a delay-discounting gradient because they allow us to isolate the effect of delay on value. For example, if at a 1 week delay and a maximum of $1,000, the indifference point is at $700 we know that, for that participant, a 1-week delay corresponds to a 30% reduction in value. This video outlines an adjusting amount delay-discounting task that identifies indifference points relatively quickly and is inexpensive and easy to administer. Once data have been collected, non-linear regression techniques are typically used to generate discounting curves. The steepness of the discounting curve reflects the degree of impulsive choice of a group or individual. These techniques have been used with a wide range of commodities and have identified populations that are relatively impulsive. For example, people with substance abuse problems discount delayed rewards more steeply than control participants. Although degree of discounting varies as a function of the commodity examined, discounting of one commodity correlates with discounting of other commodities, which suggests that discounting may be a persistent pattern of behavior(1).

  8. Do the adjusting-delay and increasing-delay tasks measure the same construct: delay discounting?

    PubMed

    Craig, Andrew R; Maxfield, Adam D; Stein, Jeffrey S; Renda, C Renee; Madden, Gregory J

    2014-08-01

    Delay discounting describes the subjective devaluation of a reward when it is delayed. In animals, the adjusting-delay (AD) and increasing-delay (ID) tasks often are used to assess individual differences in, and drug effects on, delay discounting. No study to date, however, has compared systematically the measures of discounting produced in these tasks. The current study examined the correlation between measures of delay discounting derived from AD and ID procedures. Twenty rats completed 30 sessions under each task (order counterbalanced across rats). Quantitative measures of delay discounting produced by the two tasks were positively correlated, suggesting that the AD and ID tasks measure the same underlying facet of impulsive choice (i.e. individual or conjoint sensitivities to reward delay and magnitude). The measures derived from either task, however, depended on the sequences in which the tasks were experienced. That is, pre-exposure to one task decreased discounting of delayed rewards in the second task. Consistent with other published findings, exposure to delayed consequences during the initial discounting assessment might explain this effect. Despite the observed correlation between ID and AD indifference delays, we suggest that the ID procedure might be a more appropriate procedure for pharmacological studies.

  9. Do the Adjusting- and Increasing-Delay Tasks Measure the Same Construct – Delay Discounting?

    PubMed Central

    Craig, Andrew R.; Maxfield, Adam D.; Stein, Jeffrey S.; Renda, C. Renee; Madden, Gregory J.

    2014-01-01

    Delay discounting describes the subjective devaluation of a reward when it is delayed. In animals, the adjusting- and increasing-delay tasks often are used to assess individual differences in, and drug effects on, delay discounting. No study to date, however, has compared systematically the measures of discounting produced in these tasks. The current study examined the correlation between measures of delay discounting derived from adjusting- and increasing-delay procedures. Twenty rats completed 30 sessions under each task (order counterbalanced across rats). Quantitative measures of delay discounting produced by the two tasks were positively correlated, suggesting that the adjusting-and increasing-delay tasks measure the same underlying facet of impulsive choice (i.e., individual or conjoint sensitivities to reward delay and magnitude). The measures derived from either task, however, depended on the sequences in which the tasks were experienced. That is, pre-exposure to one task decreased discounting of delayed rewards in the second task. Consistent with other published findings, exposure to delayed consequences during the initial discounting assessment might explain this effect. Despite the observed correlation between ID and AD indifference delays, we suggest that the ID procedure might be a more appropriate procedure for pharmacological studies. PMID:24978484

  10. 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.

  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. Assessing Measurement Invariance for Spanish Sentence Repetition and Morphology Elicitation Tasks

    ERIC Educational Resources Information Center

    Kapantzoglou, Maria; Thompson, Marilyn S.; Gray, Shelley; Restrepo, M. Adelaida

    2016-01-01

    Purpose: The purpose of this study was to evaluate evidence supporting the construct validity of two grammatical tasks (sentence repetition, morphology elicitation) included in the Spanish Screener for Language Impairment in Children (Restrepo, Gorin, & Gray, 2013). We evaluated if the tasks measured the targeted grammatical skills in the same…

  13. Heritability of Cognitive Abilities as Measured by Mental Chronometric Tasks: A Meta-Analysis

    ERIC Educational Resources Information Center

    Beaujean, A.A.

    2005-01-01

    The purpose of this study is to meta-analyze the published studies that measure the performance differences in mental chronometric tasks using a behavioral genetic research design. Because chronometric tasks are so simple, individual differences in the time it takes to complete them are largely due to underlying biological and physiological…

  14. Measuring Grammatical Development in Bilingual Mandarin-English Speaking Children with a Sentence Repetition Task

    ERIC Educational Resources Information Center

    Woon, Chai Ping; Yap, Ngee Thai; Lim, Hui Woan; Wong, Bee Eng

    2014-01-01

    Sentence repetition (SR) tasks have been used to measure children's expressive language skills in normal and abnormal language development, and to examine the development of the speaking skills in second language acquisition, as well as to survey the proficiency of bilingual language development. Recently, SR tasks have been recognized as a…

  15. Measuring Spatial Ability with a Computer Managed Task.

    ERIC Educational Resources Information Center

    McDaniel, Ernest; And Others

    This study presents data augmenting the validity studies of the Wheatley Cube (McDaniel and Kroll, 1984), a computer managed test of spatial visualization. Twenty-one students in pilot training are administered several instruments designed to measure the ability to construct a cognitive three-dimensional space, including: (1) the Wheatley Cube,…

  16. Critical Tasks to Measure Teacher Performance: A Design Model

    ERIC Educational Resources Information Center

    Wilkerson, Judy R.; Lang, William Steve

    2006-01-01

    NCATE (2002) requires the measurement of knowledge, skills, and dispositions as part of its accreditation requirements for teacher education programs (Standard 1) and the use of unit assessment systems to aggregate and analyse data with a view toward program improvement (Standard 2). Data must indicate that candidates meet professional, state, and…

  17. Intra- and Inter-Task Reliability of Spatial Attention Measures in Pseudoneglect

    PubMed Central

    Learmonth, Gemma; Gallagher, Aodhan; Gibson, Jamie; Thut, Gregor; Harvey, Monika

    2015-01-01

    Healthy young adults display a leftward asymmetry of spatial attention (“pseudoneglect”) that has been measured with a wide range of different tasks. Yet at present there is a lack of systematic evidence that the tasks commonly used in research today are i) stable measures over time and ii) provide similar measures of spatial bias. Fifty right-handed young adults were tested on five tasks (manual line bisection, landmark, greyscales, gratingscales and lateralised visual detection) on two different days. All five tasks were found to be stable measures of bias over the two testing sessions, indicating that each is a reliable measure in itself. Surprisingly, no strongly significant inter-task correlations were found. However, principal component analysis revealed left-right asymmetries to be subdivided in 4 main components, namely asymmetries in size judgements (manual line bisection and landmark), luminance judgements (greyscales), stimulus detection (lateralised visual detection) and judgements of global/local features (manual line bisection and grating scales). The results align with recent research on hemispatial neglect which conceptualises the condition as multi-component rather than a single pathological deficit of spatial attention. We conclude that spatial biases in judgment of visual stimulus features in healthy adults (e.g., pseudoneglect) is also a multi-component phenomenon that may be captured by variations in task demands which engage task-dependent patterns of activation within the attention network. PMID:26378925

  18. Task committee on experimental uncertainty and measurement errors in hydraulic engineering: An update

    USGS Publications Warehouse

    Wahlin, B.; Wahl, T.; Gonzalez-Castro, J. A.; Fulford, J.; Robeson, M.

    2005-01-01

    As part of their long range goals for disseminating information on measurement techniques, instrumentation, and experimentation in the field of hydraulics, the Technical Committee on Hydraulic Measurements and Experimentation formed the Task Committee on Experimental Uncertainty and Measurement Errors in Hydraulic Engineering in January 2003. The overall mission of this Task Committee is to provide information and guidance on the current practices used for describing and quantifying measurement errors and experimental uncertainty in hydraulic engineering and experimental hydraulics. The final goal of the Task Committee on Experimental Uncertainty and Measurement Errors in Hydraulic Engineering is to produce a report on the subject that will cover: (1) sources of error in hydraulic measurements, (2) types of experimental uncertainty, (3) procedures for quantifying error and uncertainty, and (4) special practical applications that range from uncertainty analysis for planning an experiment to estimating uncertainty in flow monitoring at gaging sites and hydraulic structures. Currently, the Task Committee has adopted the first order variance estimation method outlined by Coleman and Steele as the basic methodology to follow when assessing the uncertainty in hydraulic measurements. In addition, the Task Committee has begun to develop its report on uncertainty in hydraulic engineering. This paper is intended as an update on the Task Committee's overall progress. Copyright ASCE 2005.

  19. What is novel in the novelty oddball paradigm? Functional significance of the novelty P3 event-related potential as revealed by independent component analysis.

    PubMed

    Debener, Stefan; Makeig, Scott; Delorme, Arnaud; Engel, Andreas K

    2005-03-01

    To better understand whether voluntary attention affects how the brain processes novel events, variants of the auditory novelty oddball paradigm were presented to two different groups of human volunteers. One group of subjects (n=16) silently counted rarely presented 'infrequent' tones (p=0.10), interspersed with 'novel' task-irrelevant unique environmental sounds (p=0.10) and frequently presented 'standard' tones (p=0.80). A second group of subjects (n=17) silently counted the 'novel' environmental sounds, the 'infrequent' tones now serving as the task-irrelevant deviant events. Analysis of event-related potentials (ERPs) recorded from 63 scalp channels suggested a spatiotemporal overlap of fronto-central novelty P3 and centro-parietal P3 (P3b) ERP features in both groups. Application of independent component analysis (ICA) to concatenated single trials revealed two independent component clusters that accounted for portions of the novelty P3 and P3b response features, respectively. The P3b-related ICA cluster contributed to the novelty P3 amplitude response to novel environmental sounds. In contrast to the scalp ERPs, the amplitude of the novelty P3 related cluster was not affected by voluntary attention, that is, by the target/nontarget distinction. This result demonstrates the usefulness of ICA for disentangling spatiotemporally overlapping ERP processes and provides evidence that task irrelevance is not a necessary feature of novelty processing.

  20. Measuring listening effort: driving simulator vs. simple dual-task paradigm

    PubMed Central

    Wu, Yu-Hsiang; Aksan, Nazan; Rizzo, Matthew; Stangl, Elizabeth; Zhang, Xuyang; Bentler, Ruth

    2014-01-01

    Objectives The dual-task paradigm has been widely used to measure listening effort. The primary objectives of the study were to (1) investigate the effect of hearing aid amplification and a hearing aid directional technology on listening effort measured by a complicated, more real world dual-task paradigm, and (2) compare the results obtained with this paradigm to a simpler laboratory-style dual-task paradigm. Design The listening effort of adults with hearing impairment was measured using two dual-task paradigms, wherein participants performed a speech recognition task simultaneously with either a driving task in a simulator or a visual reaction-time task in a sound-treated booth. The speech materials and road noises for the speech recognition task were recorded in a van traveling on the highway in three hearing aid conditions: unaided, aided with omni directional processing (OMNI), and aided with directional processing (DIR). The change in the driving task or the visual reaction-time task performance across the conditions quantified the change in listening effort. Results Compared to the driving-only condition, driving performance declined significantly with the addition of the speech recognition task. Although the speech recognition score was higher in the OMNI and DIR conditions than in the unaided condition, driving performance was similar across these three conditions, suggesting that listening effort was not affected by amplification and directional processing. Results from the simple dual-task paradigm showed a similar trend: hearing aid technologies improved speech recognition performance, but did not affect performance in the visual reaction-time task (i.e., reduce listening effort). The correlation between listening effort measured using the driving paradigm and the visual reaction-time task paradigm was significant. The finding showing that our older (56 to 85 years old) participants’ better speech recognition performance did not result in reduced

  1. Students' Coordination of Geometric Reasoning and Measuring Strategies on a Fixed Perimeter Task: Developing Mathematical Understanding of Linear Measurement

    ERIC Educational Resources Information Center

    Barrett, Jeffrey E.; Clements, Douglas H.; Klanderman, David; Pennisi, Sarah-Jean; Polaki, Mokaeane V.

    2006-01-01

    This article examines students' development of levels of understanding for measurement by describing the coordination of geometric reasoning with measurement and numerical strategies. In analyzing the reasoning and argumentation of 38 Grade 2 through Grade 10 students on linear measure tasks, we found support for the application and elaboration of…

  2. Time estimation as a secondary task to measure workload. [attention sharing effect on operator performance

    NASA Technical Reports Server (NTRS)

    Hart, S. G.

    1975-01-01

    Variation in the length of time productions and verbal estimates of duration was investigated to determine the influence of concurrent activity on operator time perception. The length of 10-, 20-, and 30-sec intervals produced while performing six different compensatory tracking tasks was significantly longer, 23% on the average, than those produced while performing no other task. Verbal estimates of session duration, taken at the end of each of 27 experimental sessions, reflected a parallel increase in subjective underestimation of the passage of time as the difficulty of the task performed increased. These data suggest that estimates of duration made while performing a manual control task provide stable and sensitive measures of the workload imposed by the primary task, with minimal interference.

  3. Measuring deviant sexual interest in adolescents using the emotional Stroop task.

    PubMed

    Price, Shelley A; Beech, Anthony R; Mitchell, Ian; Humphreys, Glyn W

    2014-10-01

    Adolescent sexual abusers are a heterogeneous group of offenders that often receive generic assessment and treatment services that are modeled on research findings from adult sex offender samples. The emotional Stroop task has been used to measure deviant sexual interest in adult samples. The purpose of the present study was to test whether the emotional Stroop task could also be used to assess deviant sexual interest in adolescent samples. Three groups of adolescents (a) sexual abusers (n = 24); (b) offending controls (n = 21); and (c) nonoffending controls (n = 21) completed two emotional Stroop tasks related to deviant sexual interest and tests of executive function. Adolescent sexual abusers were significantly slower to color-name some word stimuli than both adolescent offending controls and adolescent nonoffending controls. However, the task was unable to differentiate between the groups on most of the Stroop word categories. Very little research has been conducted with adolescent offender samples and the emotional Stroop task. Reaction time (RT) and Stroop bias outcome data for adolescent samples appear to be more unsystematic and weaker than has been observed in previous adult data. Based on potential difficulties with reading and development, the emotional Stroop task may not be a task suitable for measuring deviant sexual interest in adolescent samples.

  4. Measuring pilot workload in a moving-base simulator. I Asynchronous secondary choice-reaction task

    NASA Technical Reports Server (NTRS)

    Kantowitz, B. H.; Hart, S. G.; Bortolussi, M. R.

    1983-01-01

    The de facto method for measuring airplane pilot workload is based upon subjective ratings. While researchers agree that such subjective data should be bolstered by using objective behavioral measures, results to date have been mixed. No clear objective technique has surfaced as the metric of choice. It is believed that this difficulty is in part due to neglect of theoretical work in psychology that predicts some of the difficulties that are inherent in a futile search for 'the one and only' best secondary task to measure workload. An initial study that used both subjective ratings and an asynchronous choice-reaction secondary task was conducted to determine if such a secondary task could indeed meet the methodological constraints imposed by current theories of attention. Two variants of a flight scenario were combined with two levels of the secondary task. Appropriate single-task control conditions were also included. Results give grounds for cautious optimism but indicate that future research should use synchronous secondary tasks where possible.

  5. Simultaneous measurement of time-domain fNIRS and physiological signals during a cognitive task

    NASA Astrophysics Data System (ADS)

    Jelzow, A.; Tachtsidis, I.; Kirilina, E.; Niessing, M.; Brühl, R.; Wabnitz, H.; Heine, A.; Ittermann, B.; Macdonald, R.

    2011-07-01

    Functional near-infrared spectroscopy (fNIRS) is a commonly used technique to measure the cerebral vascular response related to brain activation. It is known that systemic physiological processes, either independent or correlated with the stimulation task, can influence the optical signal making its interpretation challenging. The aim of the present work is to investigate the impact of task-evoked changes in the systemic physiology on fNIRS measurements for a cognitive paradigm. For this purpose we carried out simultaneous measurements of time-domain fNIRS on the forehead and systemic physiological signals, i.e. mean blood pressure, heart rate, respiration, galvanic skin response, scalp blood flow (flux) and red blood cell (RBC) concentration changes. We performed measurements on 15 healthy volunteers during a semantic continuous performance task (CPT). The optical data was analyzed in terms of depth-selective moments of distributions of times of flight of photons through the tissue. In addition, cerebral activation was localized by a subsequent fMRI experiment on the same subject population using the same task. We observed strong non-cerebral task-evoked changes in concentration changes of oxygenated hemoglobin in the forehead. We investigated the temporal behavior and mutual correlations between hemoglobin changes and the systemic processes. Mean blood pressure (BP), galvanic skin response (GSR) and heart rate exhibited significant changes during the activation period, whereby BP and GSR showed the highest correlation with optical measurements.

  6. What Does Rapid Automatized Naming Measure? A New RAN Task Compared to Naming and Lexical Decision

    ERIC Educational Resources Information Center

    Wile, Tammy L.; Borowsky, Ron

    2004-01-01

    The present research investigated the relationship between Rapid Automatized Naming (RAN) performance, letter-string reading measures of sight vocabulary (SV) and phonetic decoding (PD), and lexical decision. Criterion-based naming rates were obtained from three types of RAN tasks: digits, letters, and letter sounds. Latency measures were obtained…

  7. Measuring motivation in schizophrenia: Is a general state of motivation necessary for task-specific motivation?

    PubMed Central

    Choi, Jimmy; Choi, Kee-Hong; Reddy, Felice; Fiszdon, Joanna M.

    2014-01-01

    Despite the important role of motivation in rehabilitation and functional outcomes in schizophrenia, to date, there has been little emphasis on how motivation is assessed. This is important, since different measures may tap potentially discrete motivational constructs, which in turn may have very different associations to important outcomes. In the current study, we used baseline data from 71 schizophrenia spectrum outpatients enrolled in a rehabilitation program to examine the relationship between task-specific motivation, as measured by the Intrinsic Motivation Inventory (IMI), and a more general state of volition/initiation, as measured by the three item Quality of Life (QLS) motivation index. We also examined the relationship of these motivation measures to demographic, clinical and functional variables relevant to rehabilitation outcomes. The two motivation measures were not correlated, and participants with low general state motivation exhibited a full range of task-specific motivation. Only the QLS motivation index correlated with variables relevant to rehabilitation outcomes. The lack of associations between QLS motivation index and IMI subscales suggests that constructs tapped by these measures may be divergent in schizophrenia, and specifically that task-specific intrinsic motivation is not contingent on a general state of motivation. That is, even in individuals with a general low motivational state (i.e. amotivation), interventions aimed at increasing task-specific motivation may still be effective. Moreover, the pattern of interrelationships between the QLS motivation index and variables relevant to psychosocial rehabilitation supports its use in treatment outcome studies. PMID:24529609

  8. Measuring motivation in schizophrenia: is a general state of motivation necessary for task-specific motivation?

    PubMed

    Choi, Jimmy; Choi, Kee-Hong; Felice Reddy, L; Fiszdon, Joanna M

    2014-03-01

    Despite the important role of motivation in rehabilitation and functional outcomes in schizophrenia, to date, there has been little emphasis on how motivation is assessed. This is important, since different measures may tap potentially discrete motivational constructs, which in turn may have very different associations to important outcomes. In the current study, we used baseline data from 71 schizophrenia spectrum outpatients enrolled in a rehabilitation program to examine the relationship between task-specific motivation, as measured by the Intrinsic Motivation Inventory (IMI), and a more general state of volition/initiation, as measured by the three item Quality of Life (QLS) motivation index. We also examined the relationship of these motivation measures to demographic, clinical and functional variables relevant to rehabilitation outcomes. The two motivation measures were not correlated, and participants with low general state motivation exhibited a full range of task-specific motivation. Only the QLS motivation index correlated with variables relevant to rehabilitation outcomes. The lack of associations between QLS motivation index and IMI subscales suggests that constructs tapped by these measures may be divergent in schizophrenia, and specifically that task-specific intrinsic motivation is not contingent on a general state of motivation. That is, even in individuals with a general low motivational state (i.e. amotivation), interventions aimed at increasing task-specific motivation may still be effective. Moreover, the pattern of interrelationships between the QLS motivation index and variables relevant to psychosocial rehabilitation supports its use in treatment outcome studies.

  9. The utility of brief, spectrally rich, dynamic sounds in the passive oddball paradigm.

    PubMed

    Horváth, János; Roeber, Urte; Schröger, Erich

    2009-09-25

    Experiments investigating auditory processing often utilize spectrally rich, dynamic stimuli to simulate an ecologically valid auditory environment in the laboratory. Often, however, these stimuli do not allow for a strict control of the timing of auditory sensory information which may be distributed over the whole duration of a given sound. In the present study, brief (20 ms long), dynamic, spectrally rich sounds were presented in the context of a passive oddball paradigm to young adults. The short duration made certain that the sensory information was delivered entirely within a 20 ms interval. Two sounds were presented as standards (45-45% probability), other two as deviants (5-5% probability) in random sequences, with a stimulus onset asynchrony (SOA) of 1500 ms. Deviants elicited the mismatch negativity and late difference negativity (LDN) event-related potential components. No N1-effect was produced by deviants, which suggests that the acoustic energy is spread over many different features due to the dynamic spectral properties, which, combined with the brief duration, causes insignificant refractoriness-effects at the present SOA. These results support the usefulness of brief natural sounds in auditory research. The elicitation of LDN in an adult group was an unexpected finding, because LDN is mostly found in children, but not in adults. This result might indicate that LDN elicitation depends on stimulation complexity: stimulus settings in which an LDN is registered in children but not in adults may be perceived as more complex by children than by adults. PMID:19545606

  10. An analysis of physiological signals as a measure of task engagement in a multi-limb-coordination motor-learning task.

    PubMed

    Murray, Spencer A; Goldfarb, Michael

    2015-01-01

    There is widespread agreement in the physical rehabilitation community that task engagement is essential to effective neuromuscular recovery. Despite this, there are no clear measures of such task engagement. This paper assesses the extent to which certain physiological measurements might provide a measure of task engagement. In previous studies, correlations between mental focus and certain physiological measurements have been observed in subjects performing tasks requiring mental effort. In this study, the authors analyzed whether these signals showed similar correlation when subjects performed a multi-limb-coordination motor-learning task. Subjects played a video game which required the use of both arms and one leg to play a simplified electronic drum set with varying difficulty. Heart rate (HR), skin conductance level (SCL), and facial electromyogram (EMG) were recorded while the subjects played. Analysis of the recordings showed statistically significant correlations relating task difficulty to SCL, HR and EMG amplitude in corrugator supercilii. No statistically significant correlation was observed between task difficulty and EMG in frontalis. PMID:26736703

  11. An analysis of physiological signals as a measure of task engagement in a multi-limb-coordination motor-learning task.

    PubMed

    Murray, Spencer A; Goldfarb, Michael

    2015-01-01

    There is widespread agreement in the physical rehabilitation community that task engagement is essential to effective neuromuscular recovery. Despite this, there are no clear measures of such task engagement. This paper assesses the extent to which certain physiological measurements might provide a measure of task engagement. In previous studies, correlations between mental focus and certain physiological measurements have been observed in subjects performing tasks requiring mental effort. In this study, the authors analyzed whether these signals showed similar correlation when subjects performed a multi-limb-coordination motor-learning task. Subjects played a video game which required the use of both arms and one leg to play a simplified electronic drum set with varying difficulty. Heart rate (HR), skin conductance level (SCL), and facial electromyogram (EMG) were recorded while the subjects played. Analysis of the recordings showed statistically significant correlations relating task difficulty to SCL, HR and EMG amplitude in corrugator supercilii. No statistically significant correlation was observed between task difficulty and EMG in frontalis.

  12. Relationship between Adolescent Risk Preferences on a Laboratory Task and Behavioral Measures of Risk-taking

    PubMed Central

    Rao, Uma; Sidhartha, Tanuj; Harker, Karen R.; Bidesi, Anup S.; Chen, Li-Ann; Ernst, Monique

    2010-01-01

    Purpose The goal of the study was to assess individual differences in risk-taking behavior among adolescents in the laboratory. A second aim was to evaluate whether the laboratory-based risk-taking behavior is associated with other behavioral and psychological measures associated with risk-taking behavior. Methods Eighty-two adolescents with no personal history of psychiatric disorder completed a computerized decision-making task, the Wheel of Fortune (WOF). By offering choices between clearly defined probabilities and real monetary outcomes, this task assesses risk preferences when participants are confronted with potential rewards and losses. The participants also completed a variety of behavioral and psychological measures associated with risk-taking behavior. Results Performance on the task varied based on the probability and anticipated outcomes. In the winning sub-task, participants selected low probability-high magnitude reward (high-risk choice) less frequently than high probability-low magnitude reward (low-risk choice). In the losing sub-task, participants selected low probability-high magnitude loss more often than high probability-low magnitude loss. On average, the selection of probabilistic rewards was optimal and similar to performance in adults. There were, however, individual differences in performance, and one-third of the adolescents made high-risk choice more frequently than low-risk choice while selecting a reward. After controlling for sociodemographic and psychological variables, high-risk choice on the winning task predicted “real-world” risk-taking behavior and substance-related problems. Conclusions These findings highlight individual differences in risk-taking behavior. Preliminary data on face validity of the WOF task suggest that it might be a valuable laboratory tool for studying behavioral and neurobiological processes associated with risk-taking behavior in adolescents. PMID:21257113

  13. Development of the Biology Card Sorting Task to Measure Conceptual Expertise in Biology

    PubMed Central

    Smith, Julia I.; Combs, Elijah D.; Nagami, Paul H.; Alto, Valerie M.; Goh, Henry G.; Gourdet, Muryam A. A.; Hough, Christina M.; Nickell, Ashley E.; Peer, Adrian G.; Coley, John D.; Tanner, Kimberly D.

    2013-01-01

    There are widespread aspirations to focus undergraduate biology education on teaching students to think conceptually like biologists; however, there is a dearth of assessment tools designed to measure progress from novice to expert biological conceptual thinking. We present the development of a novel assessment tool, the Biology Card Sorting Task, designed to probe how individuals organize their conceptual knowledge of biology. While modeled on tasks from cognitive psychology, this task is unique in its design to test two hypothesized conceptual frameworks for the organization of biological knowledge: 1) a surface feature organization focused on organism type and 2) a deep feature organization focused on fundamental biological concepts. In this initial investigation of the Biology Card Sorting Task, each of six analytical measures showed statistically significant differences when used to compare the card sorting results of putative biological experts (biology faculty) and novices (non–biology major undergraduates). Consistently, biology faculty appeared to sort based on hypothesized deep features, while non–biology majors appeared to sort based on either surface features or nonhypothesized organizational frameworks. Results suggest that this novel task is robust in distinguishing populations of biology experts and biology novices and may be an adaptable tool for tracking emerging biology conceptual expertise. PMID:24297290

  14. Development of the biology card sorting task to measure conceptual expertise in biology.

    PubMed

    Smith, Julia I; Combs, Elijah D; Nagami, Paul H; Alto, Valerie M; Goh, Henry G; Gourdet, Muryam A A; Hough, Christina M; Nickell, Ashley E; Peer, Adrian G; Coley, John D; Tanner, Kimberly D

    2013-01-01

    There are widespread aspirations to focus undergraduate biology education on teaching students to think conceptually like biologists; however, there is a dearth of assessment tools designed to measure progress from novice to expert biological conceptual thinking. We present the development of a novel assessment tool, the Biology Card Sorting Task, designed to probe how individuals organize their conceptual knowledge of biology. While modeled on tasks from cognitive psychology, this task is unique in its design to test two hypothesized conceptual frameworks for the organization of biological knowledge: 1) a surface feature organization focused on organism type and 2) a deep feature organization focused on fundamental biological concepts. In this initial investigation of the Biology Card Sorting Task, each of six analytical measures showed statistically significant differences when used to compare the card sorting results of putative biological experts (biology faculty) and novices (non-biology major undergraduates). Consistently, biology faculty appeared to sort based on hypothesized deep features, while non-biology majors appeared to sort based on either surface features or nonhypothesized organizational frameworks. Results suggest that this novel task is robust in distinguishing populations of biology experts and biology novices and may be an adaptable tool for tracking emerging biology conceptual expertise.

  15. Stimulus, Task, and Learning Effects on Measures of Temporal Resolution: Implications for Predictors of Language Outcome

    ERIC Educational Resources Information Center

    Smith, Nicholas A.; Trainor, Laurel J.; Gray, Kellie; Plantinga, Judy A.; Shore, David I.

    2008-01-01

    Purpose: Some studies find that temporal processing ability predicts language outcome whereas other studies do not. Resolution of this debate is hindered by the variety of temporal measures used, nonsensory loading of the tasks, and differential amounts of practice across studies. The goal of this study was to examine the effects of stimulus…

  16. Development of the Biology Card Sorting Task to Measure Conceptual Expertise in Biology

    ERIC Educational Resources Information Center

    Smith, Julia I.; Combs, Elijah D.; Nagami, Paul H.; Alto, Valerie M.; Goh, Henry G.; Gourdet, Muryam A. A.; Hough, Christina M.; Nickell, Ashley E.; Peer, Adrian G.; Coley, John D.; Tanner, Kimberly D.

    2013-01-01

    There are widespread aspirations to focus undergraduate biology education on teaching students to think conceptually like biologists; however, there is a dearth of assessment tools designed to measure progress from novice to expert biological conceptual thinking. We present the development of a novel assessment tool, the Biology Card Sorting Task,…

  17. Teacher Analysis of Student Knowledge (TASK): A Measure of Learning Trajectory-Oriented Formative Assessment

    ERIC Educational Resources Information Center

    Supovitz, Jonathan; Ebby, Caroline B.; Sirinides, Philip

    2013-01-01

    This interactive electronic report provides an overview of an innovative new instrument developed by researchers at the Consortium for Policy Research in Education (CPRE) to authentically measure teachers' formative assessment practices in mathematics. The Teacher Analysis of Student Knowledge, or TASK, instrument assesses mathematics…

  18. The Development of an Individuals-within-Dyads Multilevel Performance Measure for an Interactive Cheerleading Task

    ERIC Educational Resources Information Center

    Habeeb, Christine M.; Eklund, Robert C.

    2016-01-01

    Dyadic interactions generate direct relationships in which interdependent sport behaviors can be destructured. The focus of this investigation was to develop a two-level performance framework and corresponding measures of individual- and dyad-level sport performance. The described procedures surrounded a male-female cheerleading paired-stunt task,…

  19. Measuring Search Efficiency in Complex Visual Search Tasks: Global and Local Clutter

    ERIC Educational Resources Information Center

    Beck, Melissa R.; Lohrenz, Maura C.; Trafton, J. Gregory

    2010-01-01

    Set size and crowding affect search efficiency by limiting attention for recognition and attention against competition; however, these factors can be difficult to quantify in complex search tasks. The current experiments use a quantitative measure of the amount and variability of visual information (i.e., clutter) in highly complex stimuli (i.e.,…

  20. Clinical Utility of the Modified Stroop Task as a Treatment Outcome Measure: Questions Raised

    ERIC Educational Resources Information Center

    Ball, Jillian R.; Mitchell, Philip B.; Touyz, Stephen W.; Griffiths, Rosalyn A.; Beumont, Pierre J. V.

    2004-01-01

    Data from an outpatient treatment trial for anorexia nervosa were examined to gain preliminary insights as to whether the modified Stroop colour-naming task might offer a useful measure of treatment outcome. It was hypothesised that interference for eating-, weight- and shape-related words on a modified version on the Stroop colour-naming task…

  1. Pilot-model measurements of pilot responses in a lateral-directional control task

    NASA Technical Reports Server (NTRS)

    Adams, J. J.

    1976-01-01

    Pilot response during an aircraft bank-angle compensatory control task was measured by using an adaptive modeling technique. In the main control loop, which is the bank angle to aileron command loop, the pilot response was the same as that measured previously in single-input, single-output systems. The pilot used a rudder to aileron control coordination that canceled up to 80 percent of the vehicle yawing moment due to aileron deflection.

  2. Measurement of functional task difficulty during motor learning: What level of difficulty corresponds to the optimal challenge point?

    PubMed

    Akizuki, Kazunori; Ohashi, Yukari

    2015-10-01

    The relationship between task difficulty and learning benefit was examined, as was the measurability of task difficulty. Participants were required to learn a postural control task on an unstable surface at one of four different task difficulty levels. Results from the retention test showed an inverted-U relationship between task difficulty during acquisition and motor learning. The second-highest level of task difficulty was the most effective for motor learning, while learning was delayed at the most and least difficult levels. Additionally, the results indicate that salivary α-amylase and the performance dimension of the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) are useful indices of task difficulty. Our findings suggested that instructors may be able to adjust task difficulty based on salivary α-amylase and the performance dimension of the NASA-TLX to enhance learning. PMID:26253223

  3. Measurement of functional task difficulty during motor learning: What level of difficulty corresponds to the optimal challenge point?

    PubMed

    Akizuki, Kazunori; Ohashi, Yukari

    2015-10-01

    The relationship between task difficulty and learning benefit was examined, as was the measurability of task difficulty. Participants were required to learn a postural control task on an unstable surface at one of four different task difficulty levels. Results from the retention test showed an inverted-U relationship between task difficulty during acquisition and motor learning. The second-highest level of task difficulty was the most effective for motor learning, while learning was delayed at the most and least difficult levels. Additionally, the results indicate that salivary α-amylase and the performance dimension of the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) are useful indices of task difficulty. Our findings suggested that instructors may be able to adjust task difficulty based on salivary α-amylase and the performance dimension of the NASA-TLX to enhance learning.

  4. Two measures of performance in a peg-in-hole manipulation task with force feedback

    NASA Technical Reports Server (NTRS)

    Hill, J. W.

    1977-01-01

    The results are described from two manipulators on a peg-in-hole task, which is part of a continued effort to develop models for human performance with remote manipulators. Task difficulty is varied by changing the diameter of the peg to be inserted in a 50 mm diameter hole. An automatic measuring system records the distance between the tool being held by the manipulator and the receptacle into which it is to be inserted. The data from repeated insertions are processed by computer to determine task times, accumulated distances, and trajectories. Experiments with both the MA-11 cable-connected master-slave manipulator common to hot cell work and the MA-23 servo-controlled manipulator (with and without force feedback) are described. Comparison of these results with previous results of the Ames Manipulator shows that force feedback provides a consistent advantage.

  5. Task-based measures of image quality and their relation to radiation dose and patient risk

    PubMed Central

    Barrett, Harrison H.; Myers, Kyle J.; Hoeschen, Christoph; Kupinski, Matthew A.; Little, Mark P.

    2015-01-01

    The theory of task-based assessment of image quality is reviewed in the context of imaging with ionizing radiation, and objective figures of merit (FOMs) for image quality are summarized. The variation of the FOMs with the task, the observer and especially with the mean number of photons recorded in the image is discussed. Then various standard methods for specifying radiation dose are reviewed and related to the mean number of photons in the image and hence to image quality. Current knowledge of the relation between local radiation dose and the risk of various adverse effects is summarized, and some graphical depictions of the tradeoffs between image quality and risk are introduced. Then various dose-reduction strategies are discussed in terms of their effect on task-based measures of image quality. PMID:25564960

  6. The Betrayal Aversion Elicitation Task: An Individual Level Betrayal Aversion Measure

    PubMed Central

    Aimone, Jason; Ball, Sheryl; King-Casas, Brooks

    2015-01-01

    Research on betrayal aversion shows that individuals’ response to risk depends not only on probabilities and payoffs, but also on whether the risk includes a betrayal of trust. While previous studies focus on measuring aggregate levels of betrayal aversion, the connection between an individual’s own betrayal aversion and other individually varying factors, including risk preferences, are currently unexplored. This paper develops a new task to elicit an individual’s level of betrayal aversion that can then be compared to individual characteristics. We demonstrate the feasibility of our new task and show that our aggregate individual results are consistent with previous studies. We then use this classification to ask whether betrayal aversion is correlated with risk aversion. While we find risk aversion and betrayal aversion have no significant relationship, we do observe that risk aversion is correlated with non-social risk preferences, but not the social, betrayal related, risk component of the new task. PMID:26331944

  7. Clinical complexity in medicine: A measurement model of task and patient complexity

    PubMed Central

    Islam, R.; Weir, C.; Fiol, G. Del

    2016-01-01

    Summary Background Complexity in medicine needs to be reduced to simple components in a way that is comprehensible to researchers and clinicians. Few studies in the current literature propose a measurement model that addresses both task and patient complexity in medicine. Objective The objective of this paper is to develop an integrated approach to understand and measure clinical complexity by incorporating both task and patient complexity components focusing on infectious disease domain. The measurement model was adapted and modified to healthcare domain. Methods Three clinical Infectious Disease teams were observed, audio-recorded and transcribed. Each team included an Infectious Diseases expert, one Infectious Diseases fellow, one physician assistant and one pharmacy resident fellow. The transcripts were parsed and the authors independently coded complexity attributes. This baseline measurement model of clinical complexity was modified in an initial set of coding process and further validated in a consensus-based iterative process that included several meetings and email discussions by three clinical experts from diverse backgrounds from the Department of Biomedical Informatics at the University of Utah. Inter-rater reliability was calculated using Cohen’s kappa. Results The proposed clinical complexity model consists of two separate components. The first is a clinical task complexity model with 13 clinical complexity-contributing factors and 7 dimensions. The second is the patient complexity model with 11 complexity-contributing factors and 5 dimensions. Conclusion The measurement model for complexity encompassing both task and patient complexity will be a valuable resource for future researchers and industry to measure and understand complexity in healthcare. PMID:26404626

  8. Measuring working memory is all fun and games: a four-dimensional spatial game predicts cognitive task performance.

    PubMed

    Atkins, Sharona M; Sprenger, Amber M; Colflesh, Gregory J H; Briner, Timothy L; Buchanan, Jacob B; Chavis, Sydnee E; Chen, Sy-Yu; Iannuzzi, Gregory L; Kashtelyan, Vadim; Dowling, Eamon; Harbison, J Isaiah; Bolger, Donald J; Bunting, Michael F; Dougherty, Michael R

    2014-01-01

    We developed a novel four-dimensional spatial task called Shapebuilder and used it to predict performance on a wide variety of cognitive tasks. In six experiments, we illustrate that Shapebuilder: (1) Loads on a common factor with complex working memory (WM) span tasks and that it predicts performance on quantitative reasoning tasks and Ravens Progressive Matrices (Experiment 1), (2) Correlates well with traditional complex WM span tasks (Experiment 2), predicts performance on the conditional go/no go task (Experiment 3) and N-back (Experiment 4), and showed weak or nonsignificant correlations with the Attention Networks Task (Experiment 5), and task switching (Experiment 6). Shapebuilder shows that it exhibits minimal skew and kurtosis, and shows good reliability. We argue that Shapebuilder has many advantages over existing measures of WM, including the fact that it is largely language independent, is not prone to ceiling effects, and take less than 6 min to complete on average.

  9. Measuring working memory is all fun and games: a four-dimensional spatial game predicts cognitive task performance.

    PubMed

    Atkins, Sharona M; Sprenger, Amber M; Colflesh, Gregory J H; Briner, Timothy L; Buchanan, Jacob B; Chavis, Sydnee E; Chen, Sy-Yu; Iannuzzi, Gregory L; Kashtelyan, Vadim; Dowling, Eamon; Harbison, J Isaiah; Bolger, Donald J; Bunting, Michael F; Dougherty, Michael R

    2014-01-01

    We developed a novel four-dimensional spatial task called Shapebuilder and used it to predict performance on a wide variety of cognitive tasks. In six experiments, we illustrate that Shapebuilder: (1) Loads on a common factor with complex working memory (WM) span tasks and that it predicts performance on quantitative reasoning tasks and Ravens Progressive Matrices (Experiment 1), (2) Correlates well with traditional complex WM span tasks (Experiment 2), predicts performance on the conditional go/no go task (Experiment 3) and N-back (Experiment 4), and showed weak or nonsignificant correlations with the Attention Networks Task (Experiment 5), and task switching (Experiment 6). Shapebuilder shows that it exhibits minimal skew and kurtosis, and shows good reliability. We argue that Shapebuilder has many advantages over existing measures of WM, including the fact that it is largely language independent, is not prone to ceiling effects, and take less than 6 min to complete on average. PMID:24962121

  10. The relational responding task: toward a new implicit measure of beliefs.

    PubMed

    De Houwer, Jan; Heider, Niclas; Spruyt, Adriaan; Roets, Arne; Hughes, Sean

    2015-01-01

    We introduce the Relational Responding Task (RRT) as a tool for capturing beliefs at the implicit level. Flemish participants were asked to respond as if they believed that Flemish people are more intelligent than immigrants (e.g., respond "true" to the statement "Flemish people are wiser than immigrants") or to respond as if they believed that immigrants are more intelligent than Flemish people (e.g., respond "true" to the statement "Flemish people are dumber than immigrants"). The difference in performance between these two tasks correlated with ratings of the extent to which participants explicitly endorsed the belief that Flemish people are more intelligent than immigrants and with questionnaire measures of subtle and blatant racism. The current study provides a first step toward validating RRT effects as a viable measure of implicit beliefs.

  11. The relational responding task: toward a new implicit measure of beliefs

    PubMed Central

    De Houwer, Jan; Heider, Niclas; Spruyt, Adriaan; Roets, Arne; Hughes, Sean

    2015-01-01

    We introduce the Relational Responding Task (RRT) as a tool for capturing beliefs at the implicit level. Flemish participants were asked to respond as if they believed that Flemish people are more intelligent than immigrants (e.g., respond “true” to the statement “Flemish people are wiser than immigrants”) or to respond as if they believed that immigrants are more intelligent than Flemish people (e.g., respond “true” to the statement “Flemish people are dumber than immigrants”). The difference in performance between these two tasks correlated with ratings of the extent to which participants explicitly endorsed the belief that Flemish people are more intelligent than immigrants and with questionnaire measures of subtle and blatant racism. The current study provides a first step toward validating RRT effects as a viable measure of implicit beliefs. PMID:25852624

  12. Quantitative projections of a quality measure: Performance of a complex task

    NASA Astrophysics Data System (ADS)

    Christensen, K.; Kleppe, Gisle; Vold, Martin; Frette, Vidar

    2014-12-01

    Complex data series that arise during interaction between humans (operators) and advanced technology in a controlled and realistic setting have been explored. The purpose is to obtain quantitative measures that reflect quality in task performance: on a ship simulator, nine crews have solved the same exercise, and detailed maneuvering histories have been logged. There are many degrees of freedom, some of them connected to the fact that the vessels may be freely moved in any direction. To compare maneuvering histories, several measures were used: the time needed to reach the position of operation, the integrated angle between the hull direction and the direction of motion, and the extent of movement when the vessel is to be manually kept in a fixed position. These measures are expected to reflect quality in performance. We have also obtained expert quality evaluations of the crews. The quantitative measures and the expert evaluations, taken together, allow a ranking of crew performance. However, except for time and integrated angle, there is no correlation between the individual measures. This may indicate that complex situations with social and man-machine interactions need complex measures of quality in task performance. In general terms, we have established a context-dependent and flexible framework with quantitative measures in contact with a social-science concept that is hard to define. This approach may be useful for other (qualitative) concepts in social science that contain important information on the society.

  13. 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

  14. Complexity Measures, Task Type, and Analytic Evaluations of Speaking Proficiency in a School-Based Assessment Context

    ERIC Educational Resources Information Center

    Gan, Zhengdong

    2012-01-01

    This study, which is part of a large-scale study of using objective measures to validate assessment rating scales and assessment tasks in a high-profile school-based assessment initiative in Hong Kong, examined how grammatical complexity measures relate to task type and analytic evaluations of students' speaking proficiency in a classroom-based…

  15. An Analysis of Content and Task Dimensions of Mathematics Items Designed to Measure Level of Concept Attainment

    ERIC Educational Resources Information Center

    Harris, Margaret L.; Romberg, Thomas A.

    1974-01-01

    Thirty concepts from the areas of sets, division, and expressing relationships were studied with twelve tasks dealing with naming or selecting attributes or concepts involved. A factor analysis indicated that all concepts were measures of a single functional relationship and that all tasks measure a single underlying trait. (LS)

  16. Neural Substrates for Processing Task-Irrelevant Sad Images in Adolescents

    ERIC Educational Resources Information Center

    Wang, Lihong; Huettel, Scott; De Bellis, Michael D.

    2008-01-01

    Neural systems related to cognitive and emotional processing were examined in adolescents using event-related functional magnetic resonance imaging (fMRI). Ten healthy adolescents performed an emotional oddball task. Subjects detected infrequent circles (targets) within a continual stream of phase-scrambled images (standards). Sad and neutral…

  17. The precision of visual memory for a complex contour shape measured by a freehand drawing task.

    PubMed

    Osugi, Takayuki; Takeda, Yuji

    2013-03-01

    Contour information is an important source for object perception and memory. Three experiments examined the precision of visual short-term memory for complex contour shapes. All used a new procedure that assessed recall memory for holistic information in complex contour shapes: Participants studied, then reproduced (without cues), a contoured shape by freehand drawing. In Experiment 1 memory precision was measured by comparing Fourier descriptors for studied and reproduced contours. Results indicated survival of lower (holistic) frequency information (i.e., ⩽5cycles/perimeter) and loss of higher (detail) frequency information. Secondary tasks placed demands on either verbal memory (Experiment 2) or visual spatial memory (Experiment 3). Neither secondary task interfered with recall of complex contour shapes, suggesting that the memory system maintaining holistic shape information was independent of both the verbal memory system and the visual spatial memory subsystem of visual short-term memory. The nature of memory for complex contour shape is discussed.

  18. Measuring moment-to-moment pilot workload using synchronous presentations of secondary tasks in a motion-base trainer

    NASA Technical Reports Server (NTRS)

    Bortolussi, Michael R.; Hart, Sandra G.; Shively, Robert J.

    1987-01-01

    A simulation was conducted to determine whether the sensitivity of secondary task measures of pilot workload could be improved by synchronizing their presentation to the occurrence of specific events or pilot actions. This synchronous method of presentation was compared to the more typical asynchronous method, where secondary task presentations are independent of pilot's flight-related activities. Twelve pilots flew low- and high-difficulty scenarios in a motion-base trainer with and without concurrent secondary tasks (e.g., choice reaction time and time production). The difficulty of each scenario was manipulated by the addition of 21 flight-related tasks superimposed on a standard approach and landing sequence. The insertion of the secondary tasks did not affect primary flight performance. However, secondary task performance did reflect workload differences between scenarios and among flight segments within scenarios, replicating the results of an earlier study in which the secondary tasks were presented asynchronously (Bortolussi et al., 1986).

  19. Novelty and target processing during an auditory novelty oddball: a simultaneous event-related potential and functional magnetic resonance imaging study.

    PubMed

    Strobel, Alexander; Debener, Stefan; Sorger, Bettina; Peters, Judith C; Kranczioch, Cornelia; Hoechstetter, Karsten; Engel, Andreas K; Brocke, Burkhard; Goebel, Rainer

    2008-04-01

    Recent evidence suggests that both spatiotemporally distinct and overlapping brain regions are involved in bottom-up- and top-down-driven attentional processing. However, existing studies are based on a variety of different approaches, including electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), raising the question of how EEG and fMRI findings in this field are related to each other. The present study aimed at disentangling common from specific regions underlying bottom-up novelty-processing and top-down target-processing. Simultaneous EEG and fMRI recordings were employed to investigate how fMRI-identified brain regions contribute to event-related potential (ERP) signatures of novelty- and target-processing. Fourteen subjects performed a modified novelty oddball task in which either rare tones or novel sounds served as targets in different blocks, allowing us to separate novelty-related from mere distractor-related effects. ERP signatures of novelty- and target-processing could be identified, confirming previous research based on recordings outside the scanner. fMRI analyses revealed that, despite considerable overlap of regions activated during novelty- and target-processing, bilateral superior temporal and right inferior frontal areas showed pronounced activation related to novelty-processing. fMRI-informed ERP dipole seeding was used to integrate both signals. The source modeling results further implicated temporal and inferior frontal sources in novelty-processing. Target-related fMRI activation on the other hand was confirmed in a network comprising distributed frontoparietal regions as well as bilateral caudate nucleus and cerebellum. Most regions identified by fMRI showed a contribution to target-related ERP signatures. This pattern of findings underscores the potential of simultaneous EEG/fMRI recordings for the spatiotemporal characterization of target- and novelty-processing.

  20. A Teacher-Report Measure of Children's Task-Avoidant Behavior: A Validation Study of the Behavioral Strategy Rating Scale

    ERIC Educational Resources Information Center

    Zhang, Xiao; Nurmi, Jari-Erik; Kiuru, Noona; Lerkkanen, Marja-Kristiina; Aunola, Kaisa

    2011-01-01

    This study aims to validate a teacher-report measure of children's task-avoidant behavior, namely the Behavioral Strategy Rating Scale (BSRS), in a sample of 352 Finnish children. In each of the four waves from Kindergarten to Grade 2, teachers rated children's task-avoidant behavior using the BSRS, children completed reading and mathematics…

  1. The Switch Task for Children: Measuring Mental Flexibility in Young Children

    ERIC Educational Resources Information Center

    Dibbets, Pauline; Jolles, Jellemer

    2006-01-01

    Age-related changes in mental flexibility, in the form of task switching, were assessed in 292 children (58-156 months old). Task switching was examined with a new task for young children, the Switch Task for Children (STC). The STC consists of two easy, comparable games and does not require reading skills, which makes it suitable for children…

  2. Gait measurement system for the multi-target stepping task using a laser range sensor.

    PubMed

    Yorozu, Ayanori; Nishiguchi, Shu; Yamada, Minoru; Aoyama, Tomoki; Moriguchi, Toshiki; Takahashi, Masaki

    2015-01-01

    For the prevention of falling in the elderly, gait training has been proposed using tasks such as the multi-target stepping task (MTST), in which participants step on assigned colored targets. This study presents a gait measurement system using a laser range sensor for the MTST to evaluate the risk of falling. The system tracks both legs and measures general walking parameters such as stride length and walking speed. Additionally, it judges whether the participant steps on the assigned colored targets and detects cross steps to evaluate cognitive function. However, situations in which one leg is hidden from the sensor or the legs are close occur and are likely to lead to losing track of the legs or false tracking. To solve these problems, we propose a novel leg detection method with five observed leg patterns and global nearest neighbor-based data association with a variable validation region based on the state of each leg. In addition, methods to judge target steps and detect cross steps based on leg trajectory are proposed. From the experimental results with the elderly, it is confirmed that the proposed system can improve leg-tracking performance, judge target steps and detect cross steps with high accuracy. PMID:25985161

  3. Gait measurement system for the multi-target stepping task using a laser range sensor.

    PubMed

    Yorozu, Ayanori; Nishiguchi, Shu; Yamada, Minoru; Aoyama, Tomoki; Moriguchi, Toshiki; Takahashi, Masaki

    2015-05-13

    For the prevention of falling in the elderly, gait training has been proposed using tasks such as the multi-target stepping task (MTST), in which participants step on assigned colored targets. This study presents a gait measurement system using a laser range sensor for the MTST to evaluate the risk of falling. The system tracks both legs and measures general walking parameters such as stride length and walking speed. Additionally, it judges whether the participant steps on the assigned colored targets and detects cross steps to evaluate cognitive function. However, situations in which one leg is hidden from the sensor or the legs are close occur and are likely to lead to losing track of the legs or false tracking. To solve these problems, we propose a novel leg detection method with five observed leg patterns and global nearest neighbor-based data association with a variable validation region based on the state of each leg. In addition, methods to judge target steps and detect cross steps based on leg trajectory are proposed. From the experimental results with the elderly, it is confirmed that the proposed system can improve leg-tracking performance, judge target steps and detect cross steps with high accuracy.

  4. Gait Measurement System for the Multi-Target Stepping Task Using a Laser Range Sensor

    PubMed Central

    Yorozu, Ayanori; Nishiguchi, Shu; Yamada, Minoru; Aoyama, Tomoki; Moriguchi, Toshiki; Takahashi, Masaki

    2015-01-01

    For the prevention of falling in the elderly, gait training has been proposed using tasks such as the multi-target stepping task (MTST), in which participants step on assigned colored targets. This study presents a gait measurement system using a laser range sensor for the MTST to evaluate the risk of falling. The system tracks both legs and measures general walking parameters such as stride length and walking speed. Additionally, it judges whether the participant steps on the assigned colored targets and detects cross steps to evaluate cognitive function. However, situations in which one leg is hidden from the sensor or the legs are close occur and are likely to lead to losing track of the legs or false tracking. To solve these problems, we propose a novel leg detection method with five observed leg patterns and global nearest neighbor-based data association with a variable validation region based on the state of each leg. In addition, methods to judge target steps and detect cross steps based on leg trajectory are proposed. From the experimental results with the elderly, it is confirmed that the proposed system can improve leg-tracking performance, judge target steps and detect cross steps with high accuracy. PMID:25985161

  5. A higher illuminance induces alertness even during office hours: findings on subjective measures, task performance and heart rate measures.

    PubMed

    Smolders, K C H J; de Kort, Y A W; Cluitmans, P J M

    2012-08-20

    Nocturnal white light exposure has shown marked results on subjective and objective indicators of alertness, vitality and mood, yet effects of white light during daytime and under usual office work conditions have not been investigated extensively. The current study employed a mixed-group design (N=32), testing effects of two illuminance levels (200lx or 1000lx at eye level, 4000K) during one hour of morning versus afternoon exposure. In four repeated blocks, subjective reports, objective performance and physiological arousal were measured. Results showed effects of illuminance on subjective alertness and vitality, sustained attention in tasks, and heart rate and heart rate variability. Participants felt less sleepy and more energetic in the high versus the low lighting condition, had shorter reaction times on the psychomotor vigilance task and increased physiological arousal. Effects of illuminance on the subjective measures, as well as those on heart rate were not dependent on time of day or duration of exposure. Performance effects were most pronounced in the morning sessions and towards the end of the one-hour exposure period. The effect on heart rate variability was also most pronounced at the end of the one-hour exposure. The results demonstrate that even under normal, i.e., neither sleep nor light deprived conditions, more intense light can improve feelings of alertness and vitality, as well as objective performance and physiological arousal.

  6. A higher illuminance induces alertness even during office hours: findings on subjective measures, task performance and heart rate measures.

    PubMed

    Smolders, K C H J; de Kort, Y A W; Cluitmans, P J M

    2012-08-20

    Nocturnal white light exposure has shown marked results on subjective and objective indicators of alertness, vitality and mood, yet effects of white light during daytime and under usual office work conditions have not been investigated extensively. The current study employed a mixed-group design (N=32), testing effects of two illuminance levels (200lx or 1000lx at eye level, 4000K) during one hour of morning versus afternoon exposure. In four repeated blocks, subjective reports, objective performance and physiological arousal were measured. Results showed effects of illuminance on subjective alertness and vitality, sustained attention in tasks, and heart rate and heart rate variability. Participants felt less sleepy and more energetic in the high versus the low lighting condition, had shorter reaction times on the psychomotor vigilance task and increased physiological arousal. Effects of illuminance on the subjective measures, as well as those on heart rate were not dependent on time of day or duration of exposure. Performance effects were most pronounced in the morning sessions and towards the end of the one-hour exposure period. The effect on heart rate variability was also most pronounced at the end of the one-hour exposure. The results demonstrate that even under normal, i.e., neither sleep nor light deprived conditions, more intense light can improve feelings of alertness and vitality, as well as objective performance and physiological arousal. PMID:22564492

  7. Can Simulation Measure Differences in Task-Switching Ability Between Junior and Senior Emergency Medicine Residents?

    PubMed Central

    Smith, Dustin; Miller, Daniel G.; Cukor, Jeffrey

    2016-01-01

    Introduction Work interruptions during patient care have been correlated with error. Task-switching is identified by the Accreditation Council for Graduate Medical Education (ACGME) as a core competency for emergency medicine (EM). Simulation has been suggested as a means of assessing EM core competencies. We assumed that senior EM residents had better task-switching abilities than junior EM residents. We hypothesized that this difference could be measured by observing the execution of patient care tasks in the simulation environment when a patient with a ST-elevation myocardial infarction (STEMI) interrupted the ongoing management of a septic shock case. Methods This was a multi-site, prospective, observational, cohort study. The study population consisted of a convenience sample of EM residents in their first three years of training. Each subject performed a standardized simulated encounter by evaluating and treating a patient in septic shock. At a predetermined point in every sepsis case, the subject was given a STEMI electrocardiogram (ECG) for a separate chest pain patient in triage and required to verbalize an interpretation and action. We scored learner performance using a dichotomous checklist of critical actions covering sepsis care, ECG interpretation and triaging of the STEMI patient. Results Ninety-one subjects participated (30 postgraduate year [PGY]1s, 32 PGY2s, and 29 PGY3s). Of those, 87 properly managed the patient with septic shock (90.0% PGY1s, 100% PGY2, 96.6% PGY 3s; p=0.22). Of the 87 who successfully managed the septic shock, 80 correctly identified STEMI on the simulated STEMI patient (86.7% PGY1s, 96.9% PGY2s, 93.1% PGY3s; p=0.35). Of the 80 who successfully managed the septic shock patient and correctly identified the STEMI, 79 provided appropriate interventions for the STEMI patient (73.3% PGY1s, 93.8% PGY2s, 93.8% PGY3s; p=0.07). Conclusion When management of a septic shock patient was interrupted with a STEMI ECG in a simulated

  8. Word processing speed in peripheral vision measured with a saccadic choice task.

    PubMed

    Chanceaux, Myriam; Vitu, Françoise; Bendahman, Luisa; Thorpe, Simon; Grainger, Jonathan

    2012-03-01

    A saccadic choice task (Kirchner & Thorpe, 2006) was used to measure word processing speed in peripheral vision. To do so, word targets were accompanied by distractor stimuli, which were random strings of consonants presented in the contralateral visual field. Participants were also tested with the animal stimuli of Kirchner and Thorpe's original study. The results obtained with the animal stimuli provide a straightforward replication of prior findings, with the estimated fastest saccade latencies to animal targets being 140 ms. With the word targets, the fastest reliable saccades occurred with latencies of around 200 ms. The results obtained with word targets provide a timing estimate for word processing in peripheral vision that is incompatible with sequential-attention-shift (SAS) accounts of eye movement control in reading. PMID:22306679

  9. Monitoring task loading with multivariate EEG measures during complex forms of human-computer interaction

    NASA Technical Reports Server (NTRS)

    Smith, M. E.; Gevins, A.; Brown, H.; Karnik, A.; Du, R.

    2001-01-01

    Electroencephalographic (EEG) recordings were made while 16 participants performed versions of a personal-computer-based flight simulation task of low, moderate, or high difficulty. As task difficulty increased, frontal midline theta EEG activity increased and alpha band activity decreased. A participant-specific function that combined multiple EEG features to create a single load index was derived from a sample of each participant's data and then applied to new test data from that participant. Index values were computed for every 4 s of task data. Across participants, mean task load index values increased systematically with increasing task difficulty and differed significantly between the different task versions. Actual or potential applications of this research include the use of multivariate EEG-based methods to monitor task loading during naturalistic computer-based work.

  10. Expansion and Compression of Time Correlate with Information Processing in an Enumeration Task.

    PubMed

    Wutz, Andreas; Shukla, Anuj; Bapi, Raju S; Melcher, David

    2015-01-01

    Perception of temporal duration is subjective and is influenced by factors such as attention and context. For example, unexpected or emotional events are often experienced as if time subjectively expands, suggesting that the amount of information processed in a unit of time can be increased. Time dilation effects have been measured with an oddball paradigm in which an infrequent stimulus is perceived to last longer than standard stimuli in the rest of the sequence. Likewise, time compression for the oddball occurs when the duration of the standard items is relatively brief. Here, we investigated whether the amount of information processing changes when time is perceived as distorted. On each trial, an oddball stimulus of varying numerosity (1-14 items) and duration was presented along with standard items that were either short (70 ms) or long (1050 ms). Observers were instructed to count the number of dots within the oddball stimulus and to judge its relative duration with respect to the standards on that trial. Consistent with previous results, oddballs were reliably perceived as temporally distorted: expanded for longer standard stimuli blocks and compressed for shorter standards. The occurrence of these distortions of time perception correlated with perceptual processing; i.e. enumeration accuracy increased when time was perceived as expanded and decreased with temporal compression. These results suggest that subjective time distortions are not epiphenomenal, but reflect real changes in sensory processing. Such short-term plasticity in information processing rate could be evolutionarily advantageous in optimizing perception and action during critical moments.

  11. Thermal effects on human performance in office environment measured by integrating task speed and accuracy.

    PubMed

    Lan, Li; Wargocki, Pawel; Lian, Zhiwei

    2014-05-01

    We have proposed a method in which the speed and accuracy can be integrated into one metric of human performance. This was achieved by designing a performance task in which the subjects receive feedback on their performance by informing them whether they have committed errors, and if did, they can only proceed when the errors are corrected. Traditionally, the tasks are presented without giving this feedback and thus the speed and accuracy are treated separately. The method was examined in a subjective experiment with thermal environment as the prototypical example. During exposure in an office, 12 subjects performed tasks under two thermal conditions (neutral & warm) repeatedly. The tasks were presented with and without feedback on errors committed, as outlined above. The results indicate that there was a greater decrease in task performance due to thermal discomfort when feedback was given, compared to the performance of tasks presented without feedback.

  12. 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.

  13. 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

  14. Strong Radio Emission from a Hyperactive L Dwarf: A Low-Mass Oddball or a Rosetta Stone for Ultracool Dwarf Activity?

    NASA Astrophysics Data System (ADS)

    Burgasser, Adam J.; Melis, C.; Zauderer, B. A.; Berger, E.

    2013-01-01

    We report the detection of radio emission at 5.5 GHz from the unusually active L5 + T7 binary 2MASS J13153094-2649513AB, based on observations conducted with the Australian Telescope Compact Array. An unresolved source at the proper-motion-corrected position of 2MASS J1315-2649AB was detected with a continuum flux of 0.37+/-0.05 mJy, corresponding to a radio luminosity L_rad = (9+/-3)x10^23 erg/s or log(L_rad/L_bol) = -5.24+/-0.22. While we cannot resolve the emission to one or both components, its strength strongly favors the L5 primary, making this component the latest-type L dwarf to be detected in the radio. No detection is made at 9.0 GHz to a 5-sigma limit of 0.29 mJy, consistent with a declining power law spectrum scaling as nu^-0.5 or steeper. The emission is quiescent, with no evidence of variability or bursts over 3 hours, and no measurable polarization (V/I < 34%). 2MASS J1315-2649AB is one of the most radio-luminous ultracool dwarfs detected in quiescent emission to date, comparable in strength to other ultracool dwarfs detected while in outburst. Its combination of strong and persistent H-alpha and radio emission is unique among L dwarfs, but we find no evidence of interaction between primary and secondary. We suggest further observations that may reveal whether 2MASS J1315-2649AB is a true oddball or a benchmark for understanding the origins of activity in the coldest stars and brown dwarfs.

  15. Use of the Hayling Task to Measure Inhibition of Prepotent Responses in Normal Aging and Alzheimer's Disease

    ERIC Educational Resources Information Center

    Belleville, Sylvie; Rouleau, Nancie; Van der Linden, Martial

    2006-01-01

    This study measures the effect of Alzheimer's disease (AD) and normal aging on the inhibition of prepotent responses. AD patients, normal aged controls, and young subjects were tested with the Hayling task, which measures the ability to inhibit a semantically constrained response, and with the Stroop procedure. AD patients showed a severe deficit…

  16. Stop Signal and Conners' Continuous Performance Tasks: Test-Retest Reliability of Two Inhibition Measures in ADHD Children

    ERIC Educational Resources Information Center

    Soreni, Noam; Crosbie, Jennifer; Ickowicz, Abel; Schachar, Russell

    2009-01-01

    Objective: To measure test-retest reliability of the Stop-Signal Task (SST) and the Conners' Continuous Performance Test (CPT) in children with ADHD. Methods: 12 children with ADHD (age 11.46 plus or minus 1.66) participated in the study. Primary outcome measures were stop-signal reaction time (SSRT) for the SST and CPT's commission errors (%FP).…

  17. Effects of daytime light exposure on cognitive brain activity as measured by the ERP P300.

    PubMed

    Okamoto, Yosuke; Nakagawa, Seiji

    2015-01-01

    Exposure to light modulates not only human alertness but also cognitive functions. The present study examined the temporal dynamics of the effects of light exposure on cortical activity related to cognitive processes. Event-related potentials (ERPs) were measured while participants performed an auditory oddball task during exposure to short-, medium- or long-wavelength light or darkness. Experiments were conducted in the daytime. After a 10-min period of darkness, one of the three lights was presented for 28 min. In the control condition, darkness was maintained for the entire session. The ERP component observed approximately 300 ms after the onset of the target stimulus (P300) was analyzed. The amplitude of P300 was larger after 5-20 min of exposure to short-wavelength light than at equivalent time points in the darkness. No differences were observed in the amplitude of P300 between the medium- or long-wavelength light condition and darkness at any time point. These results suggest that the amount of attentional resource allocated to the oddball task was increased by daytime exposure to short-wavelength light, and that following approximately 5 min of exposure the impact of light on cortical activity related to cognitive processes was able to be detected.

  18. Optical measures of changes in cerebral vascular tone during voluntary breath holding and a Sternberg memory task.

    PubMed

    Tan, Chin Hong; Low, Kathy A; Schneider-Garces, Nils; Zimmerman, Benjamin; Fletcher, Mark A; Maclin, Edward L; Chiarelli, Antonio M; Gratton, Gabriele; Fabiani, Monica

    2016-07-01

    The human cerebral vasculature responds to changes in blood pressure and demands for oxygenation via cerebral autoregulation. Changes in cerebrovascular tone (vasoconstriction and vasodilation) also mediate the changes in blood flow measured by the BOLD fMRI signal. This cerebrovascular reactivity is known to vary with age. In two experiments, we demonstrate that cerebral pulse parameters measured using optical imaging can quantify changes in cerebral vascular tone, both globally and locally. In experiment 1, 51 older adults (age range=55-87) performed a voluntary breath-holding task while cerebral pulse amplitude measures were taken. We found significant pulse amplitude variations across breath-holding periods, indicating vasodilation during, and vasoconstriction after breath holding. The breath-holding index (BHI), a measure of cerebrovascular reactivity (CVR) was derived and found to correlate with age. BHI was also correlated with performance in the Modified Mini-Mental Status Examination, even after controlling for age and education. In experiment 2, the same participants performed a Sternberg task, and changes in regional pulse amplitude between high (set-size 6) and low (set-size 2) task loads were compared. Only task-related areas in the fronto-parietal network (FPN) showed significant reduction in pulse amplitude, indicating vasodilation. Non-task-related areas such as the somatosensory and auditory cortices did not show such reductions. Taken together, these experiments suggest that optical pulse parameters can index changes in brain vascular tone both globally and locally, using both physiological and cognitive load manipulations.

  19. Measurement and Evidence of Computer-Based Task Switching and Multitasking by "Net Generation" Students

    ERIC Educational Resources Information Center

    Judd, Terry; Kennedy, Gregor

    2011-01-01

    Logs of on-campus computer and Internet usage were used to conduct a study of computer-based task switching and multitasking by undergraduate medical students. A detailed analysis of over 6000 individual sessions revealed that while a majority of students engaged in both task switching and multitasking behaviours, they did so less frequently than…

  20. Measuring Task Posing Cycles: Mathematical Letter Writing between Algebra Students and Preservice Teachers

    ERIC Educational Resources Information Center

    Norton, Anderson; Rutledge, Zachary

    2006-01-01

    In a secondary school mathematics teaching methods course, a research team engaged 22 preservice secondary teachers (PSTs) in designing and posing tasks to algebra students through weekly letter writing. The goal of the tasks was for PSTs to elicit responses that would indicate student engagement in the mathematical processes described by NCTM…

  1. Role of Dual Task Design When Measuring Cognitive Load during Multimedia Learning

    ERIC Educational Resources Information Center

    Schoor, Cornelia; Bannert, Maria; Brunken, Roland

    2012-01-01

    This study assessed the role different kinds of secondary tasks play for researching the modality effect of cognitive load theory. Ninety-six university students worked with a computer-based training program for approximately 13 min and had to fulfill an additional secondary task. In a 2 x 2 factorial design, modality of information presentation…

  2. ERP measures of math anxiety: how math anxiety affects working memory and mental calculation tasks?

    PubMed

    Klados, Manousos A; Simos, Panagiotis; Micheloyannis, Sifis; Margulies, Daniel; Bamidis, Panagiotis D

    2015-01-01

    There have been several attempts to account for the impact of Mathematical Anxiety (MA) on brain activity with variable results. The present study examines the effects of MA on ERP amplitude during performance of simple arithmetic calculations and working memory tasks. Data were obtained from 32 university students as they solved four types of arithmetic problems (one- and two-digit addition and multiplication) and a working memory task comprised of three levels of difficulty (1, 2, and 3-back task). Compared to the Low-MA group, High-MA individuals demonstrated reduced ERP amplitude at frontocentral (between 180-320 ms) and centroparietal locations (between 380-420 ms). These effects were independent of task difficulty/complexity, individual performance, and general state/trait anxiety levels. Results support the hypothesis that higher levels of self-reported MA are associated with lower cortical activation during the early stages of the processing of numeric stimuli in the context of cognitive tasks.

  3. Task Feedback Effects on Conflict Monitoring and Executive Control: Relationship to Subclinical Measures of Depression

    PubMed Central

    Holmes, Avram J.; Pizzagalli, Diego A.

    2011-01-01

    Emerging evidence suggests that depression is associated with executive dysfunction, particularly after committing errors or receiving negative performance feedback. To test this hypothesis, 57 participants performed two executive tasks known to elicit errors (the Simon and Stroop Tasks) during positive or negative performance feedback. Participants with elevated depressive symptoms (Beck Depression Inventory scores ≥ 13) were characterized by impaired post-error and post-conflict performance adjustments, especially during emotionally negative task-related feedback. Additionally, for both tasks, depressive symptoms were inversely related to post-conflict reaction time adjustments following negative, but not positive, feedback. These findings suggest that subclinical depression is associated with impairments in behavioral adjustments after internal (perceived failure) and external feedback about deficient task performance. PMID:17352564

  4. The deferred imitation task as a nonverbal measure of declarative memory.

    PubMed

    McDonough, L; Mandler, J M; McKee, R D; Squire, L R

    1995-08-01

    We tested amnesic patients, patients with frontal lobe lesions, and control subjects with the deferred imitation task, a nonverbal test used to demonstrate memory abilities in human infants. On day 1, subjects were given sets of objects to obtain a baseline measure of their spontaneous performance of target actions. Then different event sequences were modeled with the object sets. On day 2, the objects were given to the subjects again, first without any instructions to imitate the sequences, and then with explicit instructions to imitate the actions exactly as they had been modeled. Control subjects and frontal lobe patients reproduced the events under both uninstructed and instructed conditions. In contrast, performance by the amnesic patients did not significantly differ from that of a second control group who had the same opportunities to handle the objects but were not shown the modeled actions. These findings suggest that deferred imitation is dependent on the brain structures essential for declarative memory that are damaged in amnesia, and they support the view that infants who imitate actions after long delays have an early capacity for long-term declarative memory.

  5. Proprioceptive ability at the lips and jaw measured using the same psychophysical discrimination task.

    PubMed

    Frayne, Ellie; Coulson, Susan; Adams, Roger; Croxson, Glen; Waddington, Gordon

    2016-06-01

    In the human face, the muscles and joints that generate movement have different properties. Whereas the jaw is a conventional condyle joint, the facial musculature has neither distinct origin nor insertion points, and the muscles do not contain muscle spindle proprioceptors. This current study aims to compare the proprioceptive ability at the orofacial muscles with that of the temporomandibular joint (TMJ) in 21 neuro-typical people aged between 18 and 65 years. A novel psychophysical task was devised for use with both structures that involved a fixed 30.5 mm start separation followed by closure onto stimuli of 5, 6, 7, 8 mm diameter. The mean proprioceptive score when using the lips was 0.84 compared to 0.79 at the jaw (p < 0.001), and response error was lower by 0.1 mm. The greater accuracy in discrimination of lip movement is significant because, unlike the muscles controlling the TMJ, the orbicularis oris muscle controlling the lips inserts on to connective tissue and other muscle, and contains no muscle spindles, implying a different more effective, proprioceptive mechanism. Additionally, unlike the lack of correlation previously observed between joints in the upper and lower limbs, at the face the scores from performing the task with the two different structures were significantly correlated (r = 0.5, p = 0.018). These data extend the understanding of proprioception being correlated for the same left and right joints and correlated within the same structure (e.g. ankle dorsiflexion and inversion), to include use-dependant proprioception, with performance in different structures being correlated through extended coordinated use. At the lips and jaw, it is likely that this arises from extensive coordinated use. This informs clinical assessment and suggests a potential for coordinated post-injury training of the lips and jaw, as well as having the potential to predict premorbid function via measurement of the uninjured structure, when monitoring

  6. Proprioceptive ability at the lips and jaw measured using the same psychophysical discrimination task.

    PubMed

    Frayne, Ellie; Coulson, Susan; Adams, Roger; Croxson, Glen; Waddington, Gordon

    2016-06-01

    In the human face, the muscles and joints that generate movement have different properties. Whereas the jaw is a conventional condyle joint, the facial musculature has neither distinct origin nor insertion points, and the muscles do not contain muscle spindle proprioceptors. This current study aims to compare the proprioceptive ability at the orofacial muscles with that of the temporomandibular joint (TMJ) in 21 neuro-typical people aged between 18 and 65 years. A novel psychophysical task was devised for use with both structures that involved a fixed 30.5 mm start separation followed by closure onto stimuli of 5, 6, 7, 8 mm diameter. The mean proprioceptive score when using the lips was 0.84 compared to 0.79 at the jaw (p < 0.001), and response error was lower by 0.1 mm. The greater accuracy in discrimination of lip movement is significant because, unlike the muscles controlling the TMJ, the orbicularis oris muscle controlling the lips inserts on to connective tissue and other muscle, and contains no muscle spindles, implying a different more effective, proprioceptive mechanism. Additionally, unlike the lack of correlation previously observed between joints in the upper and lower limbs, at the face the scores from performing the task with the two different structures were significantly correlated (r = 0.5, p = 0.018). These data extend the understanding of proprioception being correlated for the same left and right joints and correlated within the same structure (e.g. ankle dorsiflexion and inversion), to include use-dependant proprioception, with performance in different structures being correlated through extended coordinated use. At the lips and jaw, it is likely that this arises from extensive coordinated use. This informs clinical assessment and suggests a potential for coordinated post-injury training of the lips and jaw, as well as having the potential to predict premorbid function via measurement of the uninjured structure, when monitoring

  7. Measuring cognitive load during simulation-based psychomotor skills training: sensitivity of secondary-task performance and subjective ratings.

    PubMed

    Haji, Faizal A; Khan, Rabia; Regehr, Glenn; Drake, James; de Ribaupierre, Sandrine; Dubrowski, Adam

    2015-12-01

    As interest in applying cognitive load theory (CLT) to the study and design of pedagogic and technological approaches in healthcare simulation grows, suitable measures of cognitive load (CL) are needed. Here, we report a two-phased study investigating the sensitivity of subjective ratings of mental effort (SRME) and secondary-task performance (signal detection rate, SDR and recognition reaction time, RRT) as measures of CL. In phase 1 of the study, novice learners and expert surgeons attempted a visual-monitoring task under two conditions: single-task (monitoring a virtual patient's heart-rate) and dual-task (tying surgical knots on a bench-top simulator while monitoring the virtual patient's heart-rate). Novices demonstrated higher mental effort and inferior secondary-task performance on the dual-task compared to experts (RRT 1.76 vs. 0.73, p = 0.012; SDR 0.27 vs. 0.97, p < 0.001; SRME 7.75 vs. 2.80, p < 0.001). Similarly, secondary task performance deteriorated from baseline to dual-task among novices (RRT 0.63 vs. 1.76 s, p < 0.006 and SDR 1.00 vs. 0.27, p < 0.001), but not experts (RRT 0.63 vs. 0.73 s, p = 0.124 and SDR 1.00 vs. 0.97, p = 0.178). In phase 2, novices practiced surgical knot-tying on the bench top simulator during consecutive dual-task trials. A significant increase in SDR (F(9,63) = 6.63, p < 0.001, f = 0.97) and decrease in SRME (F(9,63) = 9.39, p < 0.001, f = 1.04) was observed during simulation training, while RRT did not change significantly (F(9,63) = 1.18, p < 0.32, f = 0.41). The results suggest subjective ratings and dual-task performance can be used to track changes in CL among novices, particularly in early phases of simulation-based skills training. The implications for measuring CL in simulation instructional design research are discussed.

  8. Measuring cognitive load during simulation-based psychomotor skills training: sensitivity of secondary-task performance and subjective ratings.

    PubMed

    Haji, Faizal A; Khan, Rabia; Regehr, Glenn; Drake, James; de Ribaupierre, Sandrine; Dubrowski, Adam

    2015-12-01

    As interest in applying cognitive load theory (CLT) to the study and design of pedagogic and technological approaches in healthcare simulation grows, suitable measures of cognitive load (CL) are needed. Here, we report a two-phased study investigating the sensitivity of subjective ratings of mental effort (SRME) and secondary-task performance (signal detection rate, SDR and recognition reaction time, RRT) as measures of CL. In phase 1 of the study, novice learners and expert surgeons attempted a visual-monitoring task under two conditions: single-task (monitoring a virtual patient's heart-rate) and dual-task (tying surgical knots on a bench-top simulator while monitoring the virtual patient's heart-rate). Novices demonstrated higher mental effort and inferior secondary-task performance on the dual-task compared to experts (RRT 1.76 vs. 0.73, p = 0.012; SDR 0.27 vs. 0.97, p < 0.001; SRME 7.75 vs. 2.80, p < 0.001). Similarly, secondary task performance deteriorated from baseline to dual-task among novices (RRT 0.63 vs. 1.76 s, p < 0.006 and SDR 1.00 vs. 0.27, p < 0.001), but not experts (RRT 0.63 vs. 0.73 s, p = 0.124 and SDR 1.00 vs. 0.97, p = 0.178). In phase 2, novices practiced surgical knot-tying on the bench top simulator during consecutive dual-task trials. A significant increase in SDR (F(9,63) = 6.63, p < 0.001, f = 0.97) and decrease in SRME (F(9,63) = 9.39, p < 0.001, f = 1.04) was observed during simulation training, while RRT did not change significantly (F(9,63) = 1.18, p < 0.32, f = 0.41). The results suggest subjective ratings and dual-task performance can be used to track changes in CL among novices, particularly in early phases of simulation-based skills training. The implications for measuring CL in simulation instructional design research are discussed. PMID:25761454

  9. Measuring theory of mind across middle childhood: Reliability and validity of the Silent Films and Strange Stories tasks.

    PubMed

    Devine, Rory T; Hughes, Claire

    2016-09-01

    Recent years have seen a growth of research on the development of children's ability to reason about others' mental states (or "theory of mind") beyond the narrow confines of the preschool period. The overall aim of this study was to investigate the psychometric properties of a task battery composed of items from Happé's Strange Stories task and Devine and Hughes' Silent Film task. A sample of 460 ethnically and socially diverse children (211 boys) between 7 and 13years of age completed the task battery at two time points separated by 1month. The Strange Stories and Silent Film tasks were strongly correlated even when verbal ability and narrative comprehension were taken into account, and all items loaded onto a single theory-of-mind latent factor. The theory-of-mind latent factor provided reliable estimates of performance across a wide range of theory-of-mind ability and showed no evidence of differential item functioning across gender, ethnicity, or socioeconomic status. The theory-of-mind latent factor also exhibited strong 1-month test-retest reliability, and this stability did not vary as a function of child characteristics. Taken together, these findings provide evidence for the validity and reliability of the Strange Stories and Silent Film task battery as a measure of individual differences in theory of mind suitable for use across middle childhood. We consider the methodological and conceptual implications of these findings for research on theory of mind beyond the preschool years.

  10. Measures of Bayesian Reasoning Performance on 'Normal' and 'Natural' Frequency Tasks.

    PubMed

    Stock, Rosemary; Fisk, John E; Montgomery, Catharine

    2016-01-01

    While the majority of similar studies examining Bayesian reasoning investigate how participants avoid common errors such as base-rate neglect, the current research also examines whether different formats (frequency and probability) lead to a difference in levels of absolute accuracy. In Study One, older (≥60 years) and younger (18 to 29 years) participants completed tasks in probability and normalized frequency formats. In Study 2, participants completed tasks in probability and natural frequency formats. Findings are that frequencies lead to less over-estimation, particularly in natural frequency tasks, which also reveal an interaction between age and task format whereby older adults seem unaffected by format. There was no association found between format and the avoidance of errors such as base-rate neglect. Findings are discussed in the light of dual and multi-process theories of reasoning, having failed to support the theory that frequency formats elicit System 2 reasoning processes.

  11. Short-term Music Training Enhances Complex, Distributed Neural Communication during Music and Linguistic Tasks.

    PubMed

    Carpentier, Sarah M; Moreno, Sylvain; McIntosh, Anthony R

    2016-10-01

    Musical training is frequently associated with benefits to linguistic abilities, and recent focus has been placed on possible benefits of bilingualism to lifelong executive functions; however, the neural mechanisms for such effects are unclear. The aim of this study was to gain better understanding of the whole-brain functional effects of music and second-language training that could support such previously observed cognitive transfer effects. We conducted a 28-day longitudinal study of monolingual English-speaking 4- to 6-year-old children randomly selected to receive daily music or French language training, excluding weekends. Children completed passive EEG music note and French vowel auditory oddball detection tasks before and after training. Brain signal complexity was measured on source waveforms at multiple temporal scales as an index of neural information processing and network communication load. Comparing pretraining with posttraining, musical training was associated with increased EEG complexity at coarse temporal scales during the music and French vowel tasks in widely distributed cortical regions. Conversely, very minimal decreases in complexity at fine scales and trends toward coarse-scale increases were displayed after French training during the tasks. Spectral analysis failed to distinguish between training types and found overall theta (3.5-7.5 Hz) power increases after all training forms, with spatially fewer decreases in power at higher frequencies (>10 Hz). These findings demonstrate that musical training increased diversity of brain network states to support domain-specific music skill acquisition and music-to-language transfer effects.

  12. Short-term Music Training Enhances Complex, Distributed Neural Communication during Music and Linguistic Tasks

    PubMed Central

    Carpentier, Sarah M.; Moreno, Sylvain; McIntosh, Anthony R.

    2016-01-01

    Musical training is frequently associated with benefits to linguistic abilities, and recent focus has been placed on possible benefits of bilingualism to lifelong executive functions; however, the neural mechanisms for such effects are unclear. The aim of this study was to gain better understanding of the whole-brain functional effects of music and second-language training that could support such previously observed cognitive transfer effects. We conducted a 28-day longitudinal study of monolingual English-speaking 4- to 6-year-old children randomly selected to receive daily music or French language training, excluding weekends. Children completed passive EEG music note and French vowel auditory oddball detection tasks before and after training. Brain signal complexity was measured on source waveforms at multiple temporal scales as an index of neural information processing and network communication load. Comparing pretraining with posttraining, musical training was associated with increased EEG complexity at coarse temporal scales during the music and French vowel tasks in widely distributed cortical regions. Conversely, very minimal decreases in complexity at fine scales and trends toward coarse-scale increases were displayed after French training during the tasks. Spectral analysis failed to distinguish between training types and found overall theta (3.5–7.5 Hz) power increases after all training forms, with spatially fewer decreases in power at higher frequencies (>10 Hz). These findings demonstrate that musical training increased diversity of brain network states to support domain-specific music skill acquisition and music-to-language transfer effects. PMID:27243611

  13. Short-term Music Training Enhances Complex, Distributed Neural Communication during Music and Linguistic Tasks.

    PubMed

    Carpentier, Sarah M; Moreno, Sylvain; McIntosh, Anthony R

    2016-10-01

    Musical training is frequently associated with benefits to linguistic abilities, and recent focus has been placed on possible benefits of bilingualism to lifelong executive functions; however, the neural mechanisms for such effects are unclear. The aim of this study was to gain better understanding of the whole-brain functional effects of music and second-language training that could support such previously observed cognitive transfer effects. We conducted a 28-day longitudinal study of monolingual English-speaking 4- to 6-year-old children randomly selected to receive daily music or French language training, excluding weekends. Children completed passive EEG music note and French vowel auditory oddball detection tasks before and after training. Brain signal complexity was measured on source waveforms at multiple temporal scales as an index of neural information processing and network communication load. Comparing pretraining with posttraining, musical training was associated with increased EEG complexity at coarse temporal scales during the music and French vowel tasks in widely distributed cortical regions. Conversely, very minimal decreases in complexity at fine scales and trends toward coarse-scale increases were displayed after French training during the tasks. Spectral analysis failed to distinguish between training types and found overall theta (3.5-7.5 Hz) power increases after all training forms, with spatially fewer decreases in power at higher frequencies (>10 Hz). These findings demonstrate that musical training increased diversity of brain network states to support domain-specific music skill acquisition and music-to-language transfer effects. PMID:27243611

  14. 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

  15. EEG delta oscillations index inhibitory control of contextual novelty to both irrelevant distracters and relevant task-switch cues.

    PubMed

    Prada, Laura; Barceló, Francisco; Herrmann, Christoph S; Escera, Carles

    2014-07-01

    Delta oscillations contribute to the human P300 event-related potential evoked by oddball targets, although it is unclear whether they index contextual novelty (event oddballness, novelty P3, nP3), or target-related processes (event targetness, target P3b). To examine this question, the electroencephalogram (EEG) was recorded during a cued task-switching version of the Wisconsin card-sorting test. Each target card was announced by a tone cueing either to switch or repeat the task. Novel sound distracters were interspersed among trials. Time-frequency EEG analyses revealed bursts of delta (2-4 Hz) power associated with enhanced nP3 amplitudes to both task-switch cues and novel distracters-but no association with target P3b. These findings indicate that the P300-delta response indexes contextual novelty regardless of whether novelty emanates from endogenous (new task rules) or exogenous (novel distracters) sources of information.

  16. Measuring Cognitive Load during Simulation-Based Psychomotor Skills Training: Sensitivity of Secondary-Task Performance and Subjective Ratings

    ERIC Educational Resources Information Center

    Haji, Faizal A.; Khan, Rabia; Regehr, Glenn; Drake, James; de Ribaupierre, Sandrine; Dubrowski, Adam

    2015-01-01

    As interest in applying cognitive load theory (CLT) to the study and design of pedagogic and technological approaches in healthcare simulation grows, suitable measures of cognitive load (CL) are needed. Here, we report a two-phased study investigating the sensitivity of subjective ratings of mental effort (SRME) and secondary-task performance…

  17. ERP measures of math anxiety: how math anxiety affects working memory and mental calculation tasks?

    PubMed Central

    Klados, Manousos A.; Simos, Panagiotis; Micheloyannis, Sifis; Margulies, Daniel; Bamidis, Panagiotis D.

    2015-01-01

    There have been several attempts to account for the impact of Mathematical Anxiety (MA) on brain activity with variable results. The present study examines the effects of MA on ERP amplitude during performance of simple arithmetic calculations and working memory tasks. Data were obtained from 32 university students as they solved four types of arithmetic problems (one- and two-digit addition and multiplication) and a working memory task comprised of three levels of difficulty (1, 2, and 3-back task). Compared to the Low-MA group, High-MA individuals demonstrated reduced ERP amplitude at frontocentral (between 180–320 ms) and centroparietal locations (between 380–420 ms). These effects were independent of task difficulty/complexity, individual performance, and general state/trait anxiety levels. Results support the hypothesis that higher levels of self-reported MA are associated with lower cortical activation during the early stages of the processing of numeric stimuli in the context of cognitive tasks. PMID:26578912

  18. ERP measures of math anxiety: how math anxiety affects working memory and mental calculation tasks?

    PubMed

    Klados, Manousos A; Simos, Panagiotis; Micheloyannis, Sifis; Margulies, Daniel; Bamidis, Panagiotis D

    2015-01-01

    There have been several attempts to account for the impact of Mathematical Anxiety (MA) on brain activity with variable results. The present study examines the effects of MA on ERP amplitude during performance of simple arithmetic calculations and working memory tasks. Data were obtained from 32 university students as they solved four types of arithmetic problems (one- and two-digit addition and multiplication) and a working memory task comprised of three levels of difficulty (1, 2, and 3-back task). Compared to the Low-MA group, High-MA individuals demonstrated reduced ERP amplitude at frontocentral (between 180-320 ms) and centroparietal locations (between 380-420 ms). These effects were independent of task difficulty/complexity, individual performance, and general state/trait anxiety levels. Results support the hypothesis that higher levels of self-reported MA are associated with lower cortical activation during the early stages of the processing of numeric stimuli in the context of cognitive tasks. PMID:26578912

  19. The reliability of a VISION COACH task as a measure of psychomotor skills.

    PubMed

    Xi, Yubin; Rosopa, Patrick J; Mossey, Mary; Crisler, Matthew C; Drouin, Nathalie; Kopera, Kevin; Brooks, Johnell O

    2014-10-01

    The VISION COACH™ interactive light board is designed to test and enhance participants' psychomotor skills. The primary goal of this study was to examine the test-retest reliability of the Full Field 120 VISION COACH task. One hundred eleven male and 131 female adult participants completed six trials where they responded to 120 randomly distributed lights displayed on the VISION COACH interactive light board. The mean time required for a participant to complete a trial was 101 seconds. Intraclass correlation coefficients, ranging from 0.962 to 0.987 suggest the VISION COACH Full Field 120 task was a reliable task. Cohen's d's of adjacent pairs of trials suggest learning effects did not negatively affect reliability after the third trial.

  20. The reliability of a VISION COACH task as a measure of psychomotor skills.

    PubMed

    Xi, Yubin; Rosopa, Patrick J; Mossey, Mary; Crisler, Matthew C; Drouin, Nathalie; Kopera, Kevin; Brooks, Johnell O

    2014-10-01

    The VISION COACH™ interactive light board is designed to test and enhance participants' psychomotor skills. The primary goal of this study was to examine the test-retest reliability of the Full Field 120 VISION COACH task. One hundred eleven male and 131 female adult participants completed six trials where they responded to 120 randomly distributed lights displayed on the VISION COACH interactive light board. The mean time required for a participant to complete a trial was 101 seconds. Intraclass correlation coefficients, ranging from 0.962 to 0.987 suggest the VISION COACH Full Field 120 task was a reliable task. Cohen's d's of adjacent pairs of trials suggest learning effects did not negatively affect reliability after the third trial. PMID:25181563

  1. Initial validation of the ProMIS surgical simulator as an objective measure of robotic task performance.

    PubMed

    McDonough, Patrick S; Tausch, Timothy J; Peterson, Andrew C; Brand, Timothy C

    2011-09-01

    Virtual reality robotic simulation has gained widespread momentum. In order to determine the value of virtual reality robotic simulation and its objective metrics, a reality-based robotic surgical training platform with similar analytic capabilities must be developed and validated. The ProMIS laparoscopic surgical simulator is a widely available reality-based simulation platform that has been previously validated as an objective measure of laparoscopic task performance. In this study, we evaluated the validity of the ProMIS laparoscopic surgical simulator as an objective measure of robotic task performance. Volunteers were recruited from two experience groups (novice and expert). All subjects completed three tasks (peg transfer, precision cutting, intracorporeal suture/knot) in the ProMIS laparoscopic simulator using the da Vinci robotic surgical system. Motion analysis data was obtained by the ProMIS computerized optical tracking system and objective metrics recorded included time, path length, economy of motion, and observer-recorded penalty scores. The novice group consisted of 10 subjects with no previous robotic surgical experience. The expert group consisted of 10 subjects with robotic experience. The expert group outperformed the novice group in all three tasks. Subjects rated this training platform as easy to use, as an accurate measure of their robotic surgical proficiency, and as relevant to robotic surgery. The experts described the simulator platform as useful for training and agreed with incorporating it into a residency curriculum. This study demonstrates that the ProMIS laparoscopic simulator is a face, content, and construct valid reality-based simulation platform that can be used for objectively measuring robotic task performance. PMID:27637707

  2. Exploring the Needs for Competency Measures in Eight Occupational Fields: Position Reports of Task Forces.

    ERIC Educational Resources Information Center

    Bergquist, William H.; And Others

    These position reports describe the findings of task forces which focused on the need to translate work-related experience into degree or certificate credit at postsecondary institutions. The eight occupational fields examined included Accounting, Agribusiness, Data Processing, Day Care, Electronics Technology, Management, Police Science and…

  3. Behavioral and ERP Measures of Holistic Face Processing in a Composite Task

    ERIC Educational Resources Information Center

    Letourneau, Susan M.; Mitchell, Teresa V.

    2008-01-01

    Holistic processing of faces is characterized by encoding of the face as a single stimulus. This study employed a composite face task to examine whether holistic processing varies when attention is restricted to the top as compared to the bottom half of the face, and whether evidence of holistic processing would be observed in event-related…

  4. Optometric measurements predict performance but not comfort on a virtual object placement task with a stereoscopic three-dimensional display

    NASA Astrophysics Data System (ADS)

    McIntire, John P.; Wright, Steve T.; Harrington, Lawrence K.; Havig, Paul R.; Watamaniuk, Scott N. J.; Heft, Eric L.

    2014-06-01

    Twelve participants were tested on a simple virtual object precision placement task while viewing a stereoscopic three-dimensional (S3-D) display. Inclusion criteria included uncorrected or best corrected vision of 20/20 or better in each eye and stereopsis of at least 40 arc sec using the Titmus stereotest. Additionally, binocular function was assessed, including measurements of distant and near phoria (horizontal and vertical) and distant and near horizontal fusion ranges using standard optometric clinical techniques. Before each of six 30 min experimental sessions, measurements of phoria and fusion ranges were repeated using a Keystone View Telebinocular and an S3-D display, respectively. All participants completed experimental sessions in which the task required the precision placement of a virtual object in depth at the same location as a target object. Subjective discomfort was assessed using the simulator sickness questionnaire. Individual placement accuracy in S3-D trials was significantly correlated with several of the binocular screening outcomes: viewers with larger convergent fusion ranges (measured at near distance), larger total fusion ranges (convergent plus divergent ranges, measured at near distance), and/or lower (better) stereoscopic acuity thresholds were more accurate on the placement task. No screening measures were predictive of subjective discomfort, perhaps due to the low levels of discomfort induced.

  5. fMRI Validation of fNIRS Measurements During a Naturalistic Task

    PubMed Central

    Noah, J. Adam; Ono, Yumie; Nomoto, Yasunori; Shimada, Sotaro; Tachibana, Atsumichi; Zhang, Xian; Bronner, Shaw; Hirsch, Joy

    2015-01-01

    We present a method to compare brain activity recorded with near-infrared spectroscopy (fNIRS) in a dance video game task to that recorded in a reduced version of the task using fMRI (functional magnetic resonance imaging). Recently, it has been shown that fNIRS can accurately record functional brain activities equivalent to those concurrently recorded with functional magnetic resonance imaging for classic psychophysical tasks and simple finger tapping paradigms. However, an often quoted benefit of fNIRS is that the technique allows for studying neural mechanisms of complex, naturalistic behaviors that are not possible using the constrained environment of fMRI. Our goal was to extend the findings of previous studies that have shown high correlation between concurrently recorded fNIRS and fMRI signals to compare neural recordings obtained in fMRI procedures to those separately obtained in naturalistic fNIRS experiments. Specifically, we developed a modified version of the dance video game Dance Dance Revolution (DDR) to be compatible with both fMRI and fNIRS imaging procedures. In this methodology we explain the modifications to the software and hardware for compatibility with each technique as well as the scanning and calibration procedures used to obtain representative results. The results of the study show a task-related increase in oxyhemoglobin in both modalities and demonstrate that it is possible to replicate the findings of fMRI using fNIRS in a naturalistic task. This technique represents a methodology to compare fMRI imaging paradigms which utilize a reduced-world environment to fNIRS in closer approximation to naturalistic, full-body activities and behaviors. Further development of this technique may apply to neurodegenerative diseases, such as Parkinson’s disease, late states of dementia, or those with magnetic susceptibility which are contraindicated for fMRI scanning. PMID:26132365

  6. P300-amplitudes in upper limb amputees with and without phantom limb pain in a visual oddball paradigm.

    PubMed

    Karl, Anke; Diers, Martin; Flor, Herta

    2004-07-01

    The aim of the study was to investigate to what extent cortical hyper-reactivity to visual stimuli is present in upper limb amputees. Five amputees with phantom limb pain (PLP), five amputees without PLP (Non-PLP) and 10 healthy controls (HC) were investigated using a visual oddball paradigm. Two hundred visual stimuli were presented with target stimuli occurring at a probability of 25% and standard stimuli at a probability of 75%. Event-related potentials were recorded from nine scalp positions (F3, F4, Fz, C3, C4, Cz, P3, P4, Pz). The PLP-patients had significantly higher P300-amplitudes to both types of stimuli compared to the non-PLP-patients. The HC were not significantly different from both amputee groups. P300-amplitude to targets at frontal sites in the hemisphere contralateral to the amputation was higher in the PLP patients. P300-latencies to target stimuli differed only at frontal sites with PLP-patients showing significantly longer latencies than non-PLP-patients. To standard stimuli, however, they showed significantly shorter latencies at central and parietal scalp positions. The HC had significantly shorter latencies than both amputee groups. The size of the P300-amplitude was positively correlated with the intensity of PLP. These findings suggest a higher magnitude of non-specific cortical excitability in amputees with PLP and a reduced excitability in amputees without PLP. This extends previous findings of differences in cortical excitability in PLP and non-PLP patients in the sensorimotor domain.

  7. SU-E-I-40: New Method for Measurement of Task-Specific, High-Resolution Detector System Performance

    SciTech Connect

    Loughran, B; Singh, V; Jain, A; Bednarek, D; Rudin, S

    2014-06-01

    Purpose: Although generalized linear system analytic metrics such as GMTF and GDQE can evaluate performance of the whole imaging system including detector, scatter and focal-spot, a simplified task-specific measured metric may help to better compare detector systems. Methods: Low quantum-noise images of a neuro-vascular stent with a modified ANSI head phantom were obtained from the average of many exposures taken with the high-resolution Micro-Angiographic Fluoroscope (MAF) and with a Flat Panel Detector (FPD). The square of the Fourier Transform of each averaged image, equivalent to the measured product of the system GMTF and the object function in spatial-frequency space, was then divided by the normalized noise power spectra (NNPS) for each respective system to obtain a task-specific generalized signal-to-noise ratio. A generalized measured relative object detectability (GM-ROD) was obtained by taking the ratio of the integral of the resulting expressions for each detector system to give an overall metric that enables a realistic systems comparison for the given detection task. Results: The GM-ROD provides comparison of relative performance of detector systems from actual measurements of the object function as imaged by those detector systems. This metric includes noise correlations and spatial frequencies relevant to the specific object. Additionally, the integration bounds for the GM-ROD can be selected to emphasis the higher frequency band of each detector if high-resolution image details are to be evaluated. Examples of this new metric are discussed with a comparison of the MAF to the FPD for neuro-vascular interventional imaging. Conclusion: The GM-ROD is a new direct-measured task-specific metric that can provide clinically relevant comparison of the relative performance of imaging systems. Supported by NIH Grant: 2R01EB002873 and an equipment grant from Toshiba Medical Systems Corporation.

  8. Measuring time with different neural chronometers during a synchronization-continuation task.

    PubMed

    Merchant, Hugo; Zarco, Wilbert; Pérez, Oswaldo; Prado, Luis; Bartolo, Ramón

    2011-12-01

    Temporal information processing is critical for many complex behaviors including speech and music cognition, yet its neural substrate remains elusive. We examined the neurophysiological properties of medial premotor cortex (MPC) of two Rhesus monkeys during the execution of a synchronization-continuation tapping task that includes the basic sensorimotor components of a variety of rhythmic behaviors. We show that time-keeping in the MPC is governed by separate cell populations. One group encoded the time remaining for an action, showing activity whose duration changed as a function of interval duration, reaching a peak at similar magnitudes and times with respect to the movement. The other cell group showed a response that increased in duration or magnitude as a function of the elapsed time from the last movement. Hence, the sensorimotor loops engaged during the task may depend on the cyclic interplay between different neuronal chronometers that quantify the time passed and the remaining time for an action.

  9. 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.

  10. Heartfelt empathy? No association between interoceptive awareness, questionnaire measures of empathy, reading the mind in the eyes task or the director task

    PubMed Central

    Ainley, Vivien; Maister, Lara; Tsakiris, Manos

    2015-01-01

    Interoception, defined as afferent information arising from within the body, is the basis of all emotional experience and underpins the ‘self.’ However, people vary in the extent to which interoceptive signals reach awareness. This trait modulates both their experience of emotion and their ability to distinguish ‘self’ from ‘other’ in multisensory contexts. The experience of emotion and the degree of self/other distinction or overlap are similarly fundamental to empathy, which is an umbrella term comprising affect sharing, empathic concern and perspective-taking (PT). A link has therefore often been assumed between interoceptive awareness (IA) and empathy despite a lack of clear evidence. To test the hypothesis that individual differences in both traits should correlate, we measured IA in four experiments, using a well-validated heartbeat perception task, and compared this with scores on several tests that relate to various aspects of empathy. We firstly measured scores on the Index of Interpersonal Reactivity and secondly on the Questionnaire of Cognitive and Affective Empathy. Thirdly, because the ‘simulationist’ account assumes that affect sharing is involved in recognizing emotion, we employed the ‘Reading the Mind in the Eyes Task’ for the recognition of facial expressions. Contrary to expectation, we found no significant relationships between IA and any aspect of these measures. This striking lack of direct links has important consequences for hypotheses about the extent to which empathy is necessarily embodied. Finally, to assess cognitive PT ability, which specifically requires self/other distinction, we used the ‘Director Task’ but found no relationship. We conclude that the abilities that make up empathy are potentially related to IA in a variety of conflicting ways, such that a direct association between IA and various components of empathy has yet to be established. PMID:25983715

  11. Visual-motor response of crewmen during a simulated 90-day space mission as measured by the critical task battery

    NASA Technical Reports Server (NTRS)

    Allen, R. W.; Jex, H. R.

    1973-01-01

    In order to test various components of a regenerative life support system and to obtain data on the physiological and psychological effects of long duration exposure to confinement in a space station atmosphere, four carefully screened young men were sealed in a space station simulator for 90 days and administered a tracking test battery. The battery included a clinical test (Critical Instability Task) designed to measure a subject's dynamic time delay, and a more conventional steady tracking task, during which dynamic response (describing functions) and performance measures were obtained. Good correlation was noted between the clinical critical instability scores and more detailed tracking parameters such as dynamic time delay and gain-crossover frequency. The levels of each parameter span the range observed with professional pilots and astronaut candidates tested previously. The chamber environment caused no significant decrement on the average crewman's dynamic response behavior, and the subjects continued to improve slightly in their tracking skills during the 90-day confinement period.

  12. Investigating the predictive validity of implicit and explicit measures of motivation in problem-solving behavioural tasks.

    PubMed

    Keatley, David; Clarke, David D; Hagger, Martin S

    2013-09-01

    Research into the effects of individuals'autonomous motivation on behaviour has traditionally adopted explicit measures and self-reported outcome assessment. Recently, there has been increased interest in the effects of implicit motivational processes underlying behaviour from a self-determination theory (SDT) perspective. The aim of the present research was to provide support for the predictive validity of an implicit measure of autonomous motivation on behavioural persistence on two objectively measurable tasks. SDT and a dual-systems model were adopted as frameworks to explain the unique effects offered by explicit and implicit autonomous motivational constructs on behavioural persistence. In both studies, implicit autonomous motivation significantly predicted unique variance in time spent on each task. Several explicit measures of autonomous motivation also significantly predicted persistence. Results provide support for the proposed model and the inclusion of implicit measures in research on motivated behaviour. In addition, implicit measures of autonomous motivation appear to be better suited to explaining variance in behaviours that are more spontaneous or unplanned. Future implications for research examining implicit motivation from dual-systems models and SDT approaches are outlined. PMID:22639863

  13. Investigating the predictive validity of implicit and explicit measures of motivation in problem-solving behavioural tasks.

    PubMed

    Keatley, David; Clarke, David D; Hagger, Martin S

    2013-09-01

    Research into the effects of individuals'autonomous motivation on behaviour has traditionally adopted explicit measures and self-reported outcome assessment. Recently, there has been increased interest in the effects of implicit motivational processes underlying behaviour from a self-determination theory (SDT) perspective. The aim of the present research was to provide support for the predictive validity of an implicit measure of autonomous motivation on behavioural persistence on two objectively measurable tasks. SDT and a dual-systems model were adopted as frameworks to explain the unique effects offered by explicit and implicit autonomous motivational constructs on behavioural persistence. In both studies, implicit autonomous motivation significantly predicted unique variance in time spent on each task. Several explicit measures of autonomous motivation also significantly predicted persistence. Results provide support for the proposed model and the inclusion of implicit measures in research on motivated behaviour. In addition, implicit measures of autonomous motivation appear to be better suited to explaining variance in behaviours that are more spontaneous or unplanned. Future implications for research examining implicit motivation from dual-systems models and SDT approaches are outlined.

  14. Comparing Treatment Effect Measurements in Narcolepsy: The Sustained Attention to Response Task, Epworth Sleepiness Scale and Maintenance of Wakefulness Test

    PubMed Central

    van der Heide, Astrid; van Schie, Mojca K.M.; Lammers, Gert Jan; Dauvilliers, Yves; Arnulf, Isabelle; Mayer, Geert; Bassetti, Claudio L.; Ding, Claire-Li; Lehert, Philippe; van Dijk, J. Gert

    2015-01-01

    Study Objectives: To validate the Sustained Attention to Response Task (SART) as a treatment effect measure in narcolepsy, and to compare the SART with the Maintenance of Wakefulness Test (MWT) and the Epworth Sleepiness Scale (ESS). Design: Validation of treatment effect measurements within a randomized controlled trial (RCT). Patients: Ninety-five patients with narcolepsy with or without cataplexy. Interventions: The RCT comprised a double-blind, parallel-group, multicenter trial comparing the effects of 8-w treatments with pitolisant (BF2.649), modafinil, or placebo (NCT01067222). MWT, ESS, and SART were administered at baseline and after an 8-w treatment period. The severity of excessive daytime sleepiness and cataplexy was also assessed using the Clinical Global Impression scale (CGI-C). Measurements and Results: The SART, MWT, and ESS all had good reliability, obtained for the SART and MWT using two to three sessions in 1 day. The ability to distinguish responders from nonresponders, classified using the CGI-C score, was high for all measures, with a high performance for the SART (r = 0.61) and the ESS (r = 0.54). Conclusions: The Sustained Attention to Response Task is a valid and easy-to-administer measure to assess treatment effects in narcolepsy, enhanced by combining it with the Epworth Sleepiness Scale. Citation: van der Heide A, van Schie MK, Lammers GJ, Dauvilliers Y, Arnulf I, Mayer G, Bassetti CL, Ding CL, Lehert P, van Dijk JG. Comparing treatment effect measurements in narcolepsy: the Sustained Attention to Response Task, Epworth Sleepiness Scale and Maintenance of Wakefulness Test. SLEEP 2015;38(7):1051–1058. PMID:25902810

  15. Individual differences in cognitive planning on the Tower of Hanoi task: neuropsychological maturity or measurement error?

    PubMed

    Bishop, D V; Aamodt-Leeper, G; Creswell, C; McGurk, R; Skuse, D H

    2001-05-01

    The Tower of Hanoi (ToH) task was given to 238 children aged from 7 to 15 years, and 20 adults. Individual variation within an age band was substantial. ToH score did not correlate significantly with Verbal IQ, nor with ability to inhibit a prepotent response. We readministered the ToH to 45 children after 30 to 40 days. The test-retest correlation of .5 is low in relation to accepted psychometric standards, though at least as high as reliability of the related Tower of London (ToL) in adults. The reasons for low reliability remain unclear: task novelty did not seem to be involved, as children did not improve on retest. We conclude that it is not safe to use this test to index integrity or maturation of underlying neurological systems in children. We compared our results with three published studies using the ToL with children, and found similar levels of performance on problems involving the same number of moves. Another study using automated ToL obtained much poorer scores, suggesting that computerised presentation may impair children's performance. PMID:11383971

  16. Citicoline Treatment Improves Measures of Impulsivity and Task Performance in Chronic Marijuana Smokers: A Pilot BOLD fMRI Study

    PubMed Central

    Gruber, Staci A.; Sagar, Kelly A.; Dahlgren, Mary Kathryn; Gonenç, Atilla; Conn, Nina A.; Winer, Jeffrey P.; Penetar, David; Lukas, Scott E.

    2015-01-01

    Objective Citicoline is an endogenous nucleotide that has historically been used to treat stroke, traumatic brain injury, and cognitive dysfunction. Research has also shown that citicoline treatment is associated with improved cognitive performance in substance-abusing populations. We hypothesized that marijuana (MJ) smokers who received citicoline would demonstrate improvement in cognitive performance as well as increased neural efficiency during tasks of cognitive control relative to those who received placebo. Method The current study tested this hypothesis by examining the effects of citicoline in treatment-seeking chronic MJ smokers. In an 8-week double-blind, placebo-controlled study, 19 MJ smokers were randomly assigned via a double-blind procedure to the citicoline (8 Males, 2 Females) or placebo group (9 Males, 0 Females). All participants completed fMRI scanning at baseline and after 8 weeks of treatment during two cognitive measures of inhibitory processing, the Multi Source Interference Test (MSIT) and Stroop Color Word Test, and also completed the Barratt Impulsiveness Scale (BIS-11), a self-report measure of impulsivity. Results Following the 8 week trial, MJ smokers treated with citicoline demonstrated significantly lower levels of behavioral impulsivity, improved task accuracy on both the MSIT and Stroop tasks, and exhibited significantly different patterns of brain activation relative to baseline levels and relative to those who received placebo. Conclusions Findings suggest that citicoline may facilitate the treatment of MJ use disorders by improving the cognitive skills necessary to fully engage in comprehensive treatment programs. PMID:26658924

  17. P300 component identification in auditory oddball and novel paradigms using source analysis techniques: reduced latency variability in the elderly.

    PubMed

    Maurits, Natasha M; Elting, Jan Willem; Jager, Dick K R B; van der Hoeven, Johannes H; Brouwer, Wiebo H

    2005-06-01

    P300 latency variability in normal subjects limits its diagnostic applicability as a test for cognitive function. One of the causes of variation is the overlap in P300 (P3A and P3B) components resulting in inaccurate latency determination. Recently, we have shown that identification of P3A and P3B components using source analysis techniques significantly reduces P300 latency variability in healthy younger subjects. Here, we included a novel paradigm to enhance sensitivity and investigated the efficiency of the source analysis technique in reducing the P300 latency variability in healthy older subjects. Data were recorded with a 128-channel EEG system in 28 healthy subjects (aged 53-82 years, 12 males). We used a standard two-tone and a novel three-tone auditory oddball paradigm and an established source analysis technique, and compared the latencies to those obtained with conventional P300 analysis. The source analysis method identified both P3A and P3B components in a substantially larger percentage of subjects (93% versus 32%) than the conventional method. Both for the standard and novel paradigm, the source analysis method yielded a later mean P3B latency (361.4 versus 344.2 milliseconds, P = 0.017, and 374.4 milliseconds versus 354.3 milliseconds, P = 0.014, respectively) with a smaller standard deviation (15.8 versus 26.2 milliseconds, P = 0.013, and 18.9 versus 30.0 milliseconds, P = 0.052, borderline significant, respectively) than the conventional P300 method, for subjects aged 50 to 70 years. When applying the source analysis technique, as in young healthy subjects, a considerable reduction of P300 latency variability was thus found in healthy older subjects aged 50 to 70 years for both paradigms. This may have important consequences for applications of clinical event-related potential research in the early diagnosis of dementia, because the first signs of this disease are mostly observed in this age category.

  18. Measuring novices' field mapping abilities using an in-class exercise based on expert task analysis

    NASA Astrophysics Data System (ADS)

    Caulkins, J. L.

    2010-12-01

    We are interested in developing a model of expert-like behavior for improving the teaching methods of undergraduate field geology. Our aim is to assist students in mastering the process of field mapping more efficiently and effectively and to improve their ability to think creatively in the field. To examine expert-mapping behavior, a cognitive task analysis was conducted with expert geologic mappers in an attempt to define the process of geologic mapping (i.e. to understand how experts carry out geological mapping). The task analysis indicates that expert mappers have a wealth of geologic scenarios at their disposal that they compare against examples seen in the field, experiences that most undergraduate mappers will not have had. While presenting students with many geological examples in class may increase their understanding of geologic processes, novices still struggle when presented with a novel field situation. Based on the task analysis, a short (45-minute) paper-map-based exercise was designed and tested with 14 pairs of 3rd year geology students. The exercise asks students to generate probable geologic models based on a series of four (4) data sets. Each data set represents a day’s worth of data; after the first “day,” new sheets simply include current and previously collected data (e.g. “Day 2” data set includes data from “Day 1” plus the new “Day 2” data). As the geologic complexity increases, students must adapt, reject or generate new geologic models in order to fit the growing data set. Preliminary results of the exercise indicate that students who produced more probable geologic models, and produced higher ratios of probable to improbable models, tended to go on to do better on the mapping exercises at the 3rd year field school. These results suggest that those students with more cognitively available geologic models may be more able to use these models in field settings than those who are unable to draw on these models for whatever

  19. A Measure of Inspection Time in 4-Year-Old Children: The Benny Bee IT Task

    ERIC Educational Resources Information Center

    Williams, Sarah E.; Turley, Christopher; Nettelbeck, Ted; Burns, Nicholas R.

    2009-01-01

    Inspection time (IT) measures speed of information processing without the confounding influence of motor speed. While IT has been found to relate to cognitive abilities in adults and older children, no measure of IT has been validated for use with children younger than 6 years. This study examined the validity of a new measure of IT for preschool…

  20. Measuring Mentalizing Ability: A Within-Subject Comparison between an Explicit and Implicit Version of a Ball Detection Task

    PubMed Central

    Nijhof, Annabel D.; Brass, Marcel; Bardi, Lara; Wiersema, Jan R.

    2016-01-01

    The concept of mentalizing has been widely studied, but almost exclusively through tasks with explicit instructions. Recent studies suggest that people also mentalize on a more implicit level. However, to our knowledge, no study to date has directly contrasted the effects of implicit and explicit mentalizing processes on an implicit dependent measure within-subjects. We implemented this by using two versions of an object detection task, differing only on secondary catch questions. We hypothesized that if explicit mentalizing relies on complementary processes beyond those underlying implicit mentalizing, this would be reflected in enhanced belief effects in the explicit version. Twenty-eight healthy adults watched movies in which, during the first phase, both they themselves and another agent formed a belief about the location of a ball, and although irrelevant, these beliefs could influence their ball detection reaction times in the second phase. After this response phase, there were occasional catch questions that were different for the explicit and implicit task version. Finally, self-report measures of autism spectrum disorder (ASD) symptomatology were included, as the literature suggests that ASD is related to a specific deficit in implicit mentalizing. Both in the explicit and implicit version, belief conditions had a significant effect on reaction times, with responses being slower when neither the participant nor the other agent expected the ball to be present compared to all other conditions. Importantly, after the implicit version, participants reported no explicit mentalizing awareness. In our neurotypical sample, ASD symptoms were not found to correlate with either explicit or implicit mentalizing. In conclusion, the reaction time patterns in the explicit and implicit version of the task show strikingly similar effects of mentalizing, indicating that participants processed beliefs to the same extent regardless of whether they mentalized explicitly or

  1. Attentional Effects on Phenomenological Appearance: How They Change with Task Instructions and Measurement Methods.

    PubMed

    Anderson, Britt

    2016-01-01

    It has been reported that exogenous cues accentuate contrast appearance. The empirical finding is controversial because non-veridical perception challenges the idea that attention prioritizes processing resources to make perception better, and because philosophers have used the finding to challenge representational accounts of mental experience. The present experiments confirm that when evaluated with comparison paradigms exogenous cues increase the apparent contrast. In addition, contrast appearance was also changed by simply changing the purpose of a secondary task. When comparison and discrimination reports were combined in a single experiment there was a behavioral disassociation: contrast enhanced for comparison responses, but did not change for discrimination judgments, even when participants made both types of judgment for a single stimulus. That a single object can have multiple simultaneous appearances leads inescapably to the conclusion that our unitary mental experience is illusory. PMID:27022928

  2. Attentional Effects on Phenomenological Appearance: How They Change with Task Instructions and Measurement Methods.

    PubMed

    Anderson, Britt

    2016-01-01

    It has been reported that exogenous cues accentuate contrast appearance. The empirical finding is controversial because non-veridical perception challenges the idea that attention prioritizes processing resources to make perception better, and because philosophers have used the finding to challenge representational accounts of mental experience. The present experiments confirm that when evaluated with comparison paradigms exogenous cues increase the apparent contrast. In addition, contrast appearance was also changed by simply changing the purpose of a secondary task. When comparison and discrimination reports were combined in a single experiment there was a behavioral disassociation: contrast enhanced for comparison responses, but did not change for discrimination judgments, even when participants made both types of judgment for a single stimulus. That a single object can have multiple simultaneous appearances leads inescapably to the conclusion that our unitary mental experience is illusory.

  3. Psychophysiological Control of Acognitive Task Using Adaptive Automation

    NASA Technical Reports Server (NTRS)

    Freeman, Frederick; Pope, Alan T. (Technical Monitor)

    2001-01-01

    The major focus of the present proposal was to examine psychophysiological variables related to hazardous states of awareness induced by monitoring automated systems. With the increased use of automation in today's work environment, people's roles in the work place are being redefined from that of active participant to one of passive monitor. Although the introduction of automated systems has a number of benefits, there are also a number of disadvantages regarding worker performance. Byrne and Parasuraman have argued for the use of psychophysiological measures in the development and the implementation of adaptive automation. While both performance based and model based adaptive automation have been studied, the use of psychophysiological measures, especially EEG, offers the advantage of real time evaluation of the state of the subject. The current study used the closed-loop system, developed at NASA-Langley Research Center, to control the state of awareness of subjects while they performed a cognitive vigilance task. Previous research in our laboratory, supported by NASA, has demonstrated that, in an adaptive automation, closed-loop environment, subjects perform a tracking task better under a negative than a positive, feedback condition. In addition, this condition produces less subjective workload and larger P300 event related potentials to auditory stimuli presented in a concurrent oddball task. We have also recently shown that the closed-loop system used to control the level of automation in a tracking task can also be used to control the event rate of stimuli in a vigilance monitoring task. By changing the event rate based on the subject's index of arousal, we have been able to produce improved monitoring, relative to various control groups. We have demonstrated in our initial closed-loop experiments with the the vigilance paradigm that using a negative feedback contingency (i.e. increasing event rates when the EEG index is low and decreasing event rates when

  4. 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.

  5. A time estimation task as a possible measure of emotions: difference depending on the nature of the stimulus used

    PubMed Central

    Gros, Auriane; Giroud, Maurice; Bejot, Yannick; Rouaud, Olivier; Guillemin, Sophie; Aboa Eboulé, Corine; Manera, Valeria; Daumas, Anaïs; Lemesle Martin, Martine

    2015-01-01

    Objective: Time perception is fundamental for human experience. A topic which has attracted the attention of researchers for long time is how the stimulus sensory modality (e.g., images vs. sounds) affects time judgments. However, so far, no study has directly compared the effect of two sensory modalities using emotional stimuli on time judgments. Methods: In the present two studies, healthy participants were asked to estimate the duration of a pure sound preceded by the presentation of odors vs. emotional videos as priming stimuli (implicit emotion-eliciting task). During the task, skin conductance (SC) was measured as an index of arousal. Results: Olfactory stimuli resulted in an increase in SC and in a constant time overestimation. Video stimuli resulted in an increase in SC (emotional arousal), which decreased linearly overtime. Critically, video stimuli resulted in an initial time underestimation, which shifted progressively towards a time overestimation. These results suggest that video stimuli recruited both arousal-related and attention-related mechanisms, and that the role played by these mechanisms changed overtime. Conclusions: These pilot studies highlight the importance of comparing the effect of different kinds on temporal estimation tasks, and suggests that odors are well suited to investigate arousal-related temporal distortions, while videos are ideal to investigate both arousal-related and attention-related mechanisms. PMID:26124711

  6. Spatial Visualization Tasks to Support Students' Spatial Structuring in Learning Volume Measurement

    ERIC Educational Resources Information Center

    Revina, Shintia; Zulkardi; Darmawijoyo; van Galen, Frans

    2011-01-01

    Many prior researches found that most of students in grade five tended to have difficulty in fully grasping the concept of volume measurement because they have to build their competence in spatial structuring. The unit of volume "packing" measurement must be integrated and coordinated in three-dimension. On the other hand, it is revealed…

  7. Effects of Task Training on Kindergarten Students' Performance on Early Literacy Measures

    ERIC Educational Resources Information Center

    Mackiewicz, Sara Moore

    2010-01-01

    The use of early literacy screening measures helps determine which students are at risk for future reading difficulties. However, there has been some recent concern related to the classification validity of screening measures (Hintze, Ryan, & Stoner, 2003; Nelson, 2008). Low classification validity results in the identification of a large number…

  8. The Reliability and Validity of Tasks Measuring Perception of Rapid Sequences in Children with Dyslexia

    ERIC Educational Resources Information Center

    Heath, Steve M.; Hogben, John H.

    2004-01-01

    Background: Claims that children with reading and oral language deficits have impaired perception of sequential sounds are usually based on psychophysical measures of auditory temporal processing (ATP) designed to characterise group performance. If we are to use these measures (e.g., the Tallal, 1980, Repetition Test) as the basis for intervention…

  9. Deep abdominal muscle thickness measured under sitting conditions during different stability tasks

    PubMed Central

    Nagai, Hideyuki; Akasaka, Kiyokazu; Otsudo, Takahiro; Sawada, Yutaka; Okubo, Yu

    2016-01-01

    [Purpose] This study was conducted to investigate ultrasonically determined changes in the thickness of the transversus abdominis and internal oblique muscles during different sitting conditions. [Subjects and Methods] Twenty healthy men volunteered to participate in this study. Four different sitting conditions including (A) sitting, (B) sitting with left hip flexion, (C) sitting with an abdominal hollowing maneuver (AHM), and (D) sitting with an AHM and left hip flexion, were used. Subjective exercise difficulty was evaluated. [Results] Transversus abdominis and internal oblique muscle thicknesses significantly differed between conditions, with significantly greater thickness between positions from (A) to (D). Stability of the surface when sitting had no effect on the muscle thickness of the transversus abdominis. By contrast, sitting on an unstable surface caused an increase in muscle thickness of the internal oblique in each condition. The subjects reported progressively increasing difficulty in performing each exercise in a stable position from (A) to (D), while the difficulty in an unstable position was significantly different between (A) and (B), and between (C) and (D). [Conclusion] Our findings suggest that task (B) on a stable surface should be chosen for maximal activation of transversus abdominis without inducing overactivation of the internal oblique muscle. PMID:27134381

  10. The Attentional Set Shifting Task: A Measure of Cognitive Flexibility in Mice

    PubMed Central

    Heisler, Jillian M.; Morales, Juan; Donegan, Jennifer J.; Jett, Julianne D.; Redus, Laney; O'Connor, Jason C.

    2015-01-01

    Cognitive impairment, particularly involving dysfunction of circuitry within the prefrontal cortex (PFC), represents a core feature of many neuropsychiatric and neurodevelopmental disorders, including depression, post-traumatic stress disorder, schizophrenia and autism spectrum disorder. Deficits in cognitive function also represent the most difficult symptom domain to successfully treat, as serotonin reuptake inhibitors and tricyclic antidepressants have only modest effects. Functional neuroimaging studies and postmortem analysis of human brain tissue implicate the PFC as being a primary region of dysregulation in patients with these disorders. However, preclinical behavioral assays used to assess these deficits in mouse models which can be readily manipulated genetically and could provide the basis for studies of new treatment avenues have been underutilized. Here we describe the adaptation of a behavioral assay, the attentional set shifting task (AST), to be performed in mice to assess prefrontal cortex mediated cognitive deficits. The neural circuits underlying behavior during the AST are highly conserved across humans, nonhuman primates and rodents, providing excellent face, construct and predictive validity. PMID:25741905

  11. 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.

  12. MEASURING WORKLOAD OF ICU NURSES WITH A QUESTIONNAIRE SURVEY: THE NASA TASK LOAD INDEX (TLX).

    PubMed

    Hoonakker, Peter; Carayon, Pascale; Gurses, Ayse; Brown, Roger; McGuire, Kerry; Khunlertkit, Adjhaporn; Walker, James M

    2011-01-01

    High workload of nurses in Intensive Care Units (ICUs) has been identified as a major patient safety and worker stress problem. However, relative little attention has been dedicated to the measurement of workload in healthcare. The objectives of this study are to describe and examine several methods to measure workload of ICU nurses. We then focus on the measurement of ICU nurses' workload using a subjective rating instrument: the NASA TLX.We conducted secondary data analysis on data from two, multi-side, cross-sectional questionnaire studies to examine several instruments to measure ICU nurses' workload. The combined database contains the data from 757 ICU nurses in 8 hospitals and 21 ICUs.Results show that the different methods to measure workload of ICU nurses, such as patient-based and operator-based workload, are only moderately correlated, or not correlated at all. Results show further that among the operator-based instruments, the NASA TLX is the most reliable and valid questionnaire to measure workload and that NASA TLX can be used in a healthcare setting. Managers of hospitals and ICUs can benefit from the results of this research as it provides benchmark data on workload experienced by nurses in a variety of ICUs.

  13. Mid-Task Break Improves Global Integration of Functional Connectivity in Lower Alpha Band

    PubMed Central

    Li, Junhua; Lim, Julian; Chen, Yu; Wong, Kianfoong; Thakor, Nitish; Bezerianos, Anastasios; Sun, Yu

    2016-01-01

    Numerous efforts have been devoted to revealing neurophysiological mechanisms of mental fatigue, aiming to find an effective way to reduce the undesirable fatigue-related outcomes. Until recently, mental fatigue is thought to be related to functional dysconnectivity among brain regions. However, the topological representation of brain functional connectivity altered by mental fatigue is only beginning to be revealed. In the current study, we applied a graph theoretical approach to analyse such topological alterations in the lower alpha band (8~10 Hz) of EEG data from 20 subjects undergoing a two-session experiment, in which one session includes four successive blocks with visual oddball tasks (session 1) whereas a mid-task break was introduced in the middle of four task blocks in the other session (session 2). Phase lag index (PLI) was then employed to measure functional connectivity strengths for all pairs of EEG channels. Behavior and connectivity maps were compared between the first and last task blocks in both sessions. Inverse efficiency scores (IES = reaction time/response accuracy) were significantly increased in the last task block, showing a clear effect of time-on-task in participants. Furthermore, a significant block-by-session interaction was revealed in the IES, suggesting the effectiveness of the mid-task break on maintaining task performance. More importantly, a significant session-independent deficit of global integration and an increase of local segregation were found in the last task block across both sessions, providing further support for the presence of a reshaped topology in functional brain connectivity networks under fatigue state. Moreover, a significant block-by-session interaction was revealed in the characteristic path length, small-worldness, and global efficiency, attributing to the significantly disrupted network topology in session 1 in comparison of the maintained network structure in session 2. Specifically, we found increased

  14. Mid-Task Break Improves Global Integration of Functional Connectivity in Lower Alpha Band.

    PubMed

    Li, Junhua; Lim, Julian; Chen, Yu; Wong, Kianfoong; Thakor, Nitish; Bezerianos, Anastasios; Sun, Yu

    2016-01-01

    Numerous efforts have been devoted to revealing neurophysiological mechanisms of mental fatigue, aiming to find an effective way to reduce the undesirable fatigue-related outcomes. Until recently, mental fatigue is thought to be related to functional dysconnectivity among brain regions. However, the topological representation of brain functional connectivity altered by mental fatigue is only beginning to be revealed. In the current study, we applied a graph theoretical approach to analyse such topological alterations in the lower alpha band (8~10 Hz) of EEG data from 20 subjects undergoing a two-session experiment, in which one session includes four successive blocks with visual oddball tasks (session 1) whereas a mid-task break was introduced in the middle of four task blocks in the other session (session 2). Phase lag index (PLI) was then employed to measure functional connectivity strengths for all pairs of EEG channels. Behavior and connectivity maps were compared between the first and last task blocks in both sessions. Inverse efficiency scores (IES = reaction time/response accuracy) were significantly increased in the last task block, showing a clear effect of time-on-task in participants. Furthermore, a significant block-by-session interaction was revealed in the IES, suggesting the effectiveness of the mid-task break on maintaining task performance. More importantly, a significant session-independent deficit of global integration and an increase of local segregation were found in the last task block across both sessions, providing further support for the presence of a reshaped topology in functional brain connectivity networks under fatigue state. Moreover, a significant block-by-session interaction was revealed in the characteristic path length, small-worldness, and global efficiency, attributing to the significantly disrupted network topology in session 1 in comparison of the maintained network structure in session 2. Specifically, we found increased

  15. A Cognition Analysis of QUASAR's Mathematics Performance Assessment Tasks and Their Sensitivity to Measuring Changes in Middle School Students' Thinking and Reasoning.

    ERIC Educational Resources Information Center

    Cai, Jinfa, And Others

    1996-01-01

    Presents a conceptual framework for analyzing students' mathematical understanding, reasoning, problem solving, and communication. Analyses of student responses indicated that the tasks appear to measure the complex thinking and reasoning processes that they were designed to assess. Concludes that the QUASAR assessment tasks can capture changes in…

  16. Using the Hand Laterality Judgement Task to Assess Motor Imagery: A Study of Practice Effects in Repeated Measurements

    ERIC Educational Resources Information Center

    Boonstra, Anne M.; de Vries, Sjoerd J.; Veenstra, Evelien; Tepper, Marga; Feenstra, Wya; Otten, Egbert

    2012-01-01

    The aim of this study was to determine whether there is a practice effect on the Hand Laterality Judgement Task (HLJT). The HLJT task is a mental rotation task that can be used to assess motor imagery ability in stroke patients. Thirty-three healthy individuals performed the HLJT and two control tasks twice at a 3-week interval. Differences in the…

  17. Electrophysiological measurement of interest during walking in a simulated environment.

    PubMed

    Takeda, Yuji; Okuma, Takashi; Kimura, Motohiro; Kurata, Takeshi; Takenaka, Takeshi; Iwaki, Sunao

    2014-09-01

    A reliable neuroscientific technique for objectively estimating the degree of interest in a real environment is currently required in the research fields of neuroergonomics and neuroeconomics. Toward the development of such a technique, the present study explored electrophysiological measures that reflect an observer's interest in a nearly-real visual environment. Participants were asked to walk through a simulated shopping mall and the attractiveness of the shopping mall was manipulated by opening and closing the shutters of stores. During the walking task, participants were exposed to task-irrelevant auditory probes (two-stimulus oddball sequence). The results showed a smaller P2/early P3a component of task-irrelevant auditory event-related potentials and a larger lambda response of eye-fixation-related potentials in an interesting environment (i.e., open-shutter condition) than in a boring environment (i.e., closed-shutter condition); these findings can be reasonably explained by supposing that participants allocated more attentional resources to visual information in an interesting environment than in a boring environment, and thus residual attentional resources that could be allocated to task-irrelevant auditory probes were reduced. The P2/early P3a component and the lambda response may be useful measures of interest in a real visual environment.

  18. Reply to Humphreys' and Parsons'"Piagetian Tasks Measure Intelligence and Intelligence Tests Assess Cognitive Development."

    ERIC Educational Resources Information Center

    Glass, Gene V.; Stephens, Beth

    1980-01-01

    Relationships among Piagetian reasoning assessments and standard measures of intelligence and achievement were determined in 1972 by Stephens, McLaughlin, Miller, and Glass (EJ 055 112). The data were reanalyzed by Humphreys and Parsons in 1979 (EJ 218 642). In reply, Glass and Stephens note fallacies in Humphreys' and Parsons' reasoning.…

  19. Kernel Target Alignment Parameter: A New Modelability Measure for Regression Tasks.

    PubMed

    Marcou, Gilles; Horvath, Dragos; Varnek, Alexandre

    2016-01-25

    In this paper, we demonstrate that the kernel target alignment (KTA) parameter can efficiently be used to estimate the relevance of molecular descriptors for QSAR modeling on a given data set, i.e., as a modelability measure. The efficiency of KTA to assess modelability was demonstrated in two series of QSAR modeling studies, either varying different descriptor spaces for one same data set, or comparing various data sets within one same descriptor space. Considered data sets included 25 series of various GPCR binders with ChEMBL-reported pKi values, and a toxicity data set. Employed descriptor spaces covered more than 100 different ISIDA fragment descriptor types, and ChemAxon BCUT terms. Model performances (RMSE) were seen to anticorrelate consistently with the KTA parameter. Two other modelability measures were employed for benchmarking purposes: the Jaccard distance average over the data set (Div), and a measure related to the normalized mean absolute error (MAE) obtained in 1-nearest neighbors calculations on the training set (Sim = 1 - MAE). It has been demonstrated that both Div and Sim perform similarly to KTA. However, a consensus index combining KTA, Div and Sim provides a more robust correlation with RMSE than any of the individual modelability measures.

  20. JV Task 125-Mercury Measurement in Combustion Flue Gases Short Course

    SciTech Connect

    Dennis Laudal

    2008-09-30

    The short course, designed to train personnel who have an interest in measuring mercury in combustion flue gases, was held twice at the Drury Inn in Marion, Illinois. The short course helped to provide attendees with the knowledge necessary to avoid the many pitfalls that can and do occur when measuring mercury in combustion flue gases. The first short course, May 5-8, 2008, included both a classroom-type session and hands-on demonstration of mercury-sampling equipment. The hands-on demonstration of equipment was staged at Southern Illinois Power Cooperative. Not including the Illinois Clean Coal Institute and the U.S. Department of Energy project managers, there were 12 attendees. The second short course was conducted September 16-17, 2008, but only included the classroom portion of the course; 14 people attended. In both cases, lectures were provided on the various mercury measurement methods, and interaction between attendees and EERC research personnel to discuss specific mercury measurement problems was promoted. Overall, the response to the course was excellent.

  1. Using Mean Absolute Relative Phase, Deviation Phase and Point-Estimation Relative Phase to Measure Postural Coordination in a Serial Reaching Task.

    PubMed

    Galgon, Anne K; Shewokis, Patricia A

    2016-03-01

    The objectives of this communication are to present the methods used to calculate mean absolute relative phase (MARP), deviation phase (DP) and point estimate relative phase (PRP) and compare their utility in measuring postural coordination during the performance of a serial reaching task. MARP and DP are derived from continuous relative phase time series representing the relationship between two body segments or joints during movements. MARP is a single measure used to quantify the coordination pattern and DP measures the stability of the coordination pattern. PRP also quantifies coordination patterns by measuring the relationship between the timing of maximal or minimal angular displacements of two segments within cycles of movement. Seven young adults practiced a bilateral serial reaching task 300 times over 3 days. Relative phase measures were used to evaluate inter-joint relationships for shoulder-hip (proximal) and hip-ankle (distal) postural coordination at early and late learning. MARP, PRP and DP distinguished between proximal and distal postural coordination. There was no effect of practice on any of the relative phase measures for the group, but individual differences were seen over practice. Combined, MARP and DP estimated stability of in-phase and anti-phase postural coordination patterns, however additional qualitative movement analyses may be needed to interpret findings in a serial task. We discuss the strengths and limitations of using MARP and DP and compare MARP and DP to PRP measures in assessing coordination patterns in the context of various types of skillful tasks. Key pointsMARP, DP and PRP measures coordination between segments or joint anglesAdvantages and disadvantages of each measure should be considered in relationship to the performance taskMARP and DP may capture coordination patterns and stability of the patterns during discrete tasks or phases of movements within a taskPRP and SD or PRP may capture coordination patterns and

  2. Dysfunctional information processing during an auditory event-related potential task in individuals with Internet gaming disorder.

    PubMed

    Park, M; Choi, J-S; Park, S M; Lee, J-Y; Jung, H Y; Sohn, B K; Kim, S N; Kim, D J; Kwon, J S

    2016-01-26

    Internet gaming disorder (IGD) leading to serious impairments in cognitive, psychological and social functions has gradually been increasing. However, very few studies conducted to date have addressed issues related to the event-related potential (ERP) patterns in IGD. Identifying the neurobiological characteristics of IGD is important to elucidate the pathophysiology of this condition. P300 is a useful ERP component for investigating electrophysiological features of the brain. The aims of the present study were to investigate differences between patients with IGD and healthy controls (HCs), with regard to the P300 component of the ERP during an auditory oddball task, and to examine the relationship of this component to the severity of IGD symptoms in identifying the relevant neurophysiological features of IGD. Twenty-six patients diagnosed with IGD and 23 age-, sex-, education- and intelligence quotient-matched HCs participated in this study. During an auditory oddball task, participants had to respond to the rare, deviant tones presented in a sequence of frequent, standard tones. The IGD group exhibited a significant reduction in response to deviant tones compared with the HC group in the P300 amplitudes at the midline centro-parietal electrode regions. We also found a negative correlation between the severity of IGD and P300 amplitudes. The reduced amplitude of the P300 component in an auditory oddball task may reflect dysfunction in auditory information processing and cognitive capabilities in IGD. These findings suggest that reduced P300 amplitudes may be candidate neurobiological marker for IGD.

  3. Dysfunctional information processing during an auditory event-related potential task in individuals with Internet gaming disorder

    PubMed Central

    Park, M; Choi, J-S; Park, S M; Lee, J-Y; Jung, H Y; Sohn, B K; Kim, S N; Kim, D J; Kwon, J S

    2016-01-01

    Internet gaming disorder (IGD) leading to serious impairments in cognitive, psychological and social functions has gradually been increasing. However, very few studies conducted to date have addressed issues related to the event-related potential (ERP) patterns in IGD. Identifying the neurobiological characteristics of IGD is important to elucidate the pathophysiology of this condition. P300 is a useful ERP component for investigating electrophysiological features of the brain. The aims of the present study were to investigate differences between patients with IGD and healthy controls (HCs), with regard to the P300 component of the ERP during an auditory oddball task, and to examine the relationship of this component to the severity of IGD symptoms in identifying the relevant neurophysiological features of IGD. Twenty-six patients diagnosed with IGD and 23 age-, sex-, education- and intelligence quotient-matched HCs participated in this study. During an auditory oddball task, participants had to respond to the rare, deviant tones presented in a sequence of frequent, standard tones. The IGD group exhibited a significant reduction in response to deviant tones compared with the HC group in the P300 amplitudes at the midline centro-parietal electrode regions. We also found a negative correlation between the severity of IGD and P300 amplitudes. The reduced amplitude of the P300 component in an auditory oddball task may reflect dysfunction in auditory information processing and cognitive capabilities in IGD. These findings suggest that reduced P300 amplitudes may be candidate neurobiological marker for IGD. PMID:26812042

  4. The measurement and facilitation of cooperative task performance. [reactions of humans to stress exposure

    NASA Technical Reports Server (NTRS)

    Hutchinson, R. R.

    1975-01-01

    Experiments were conducted to determine under what conditions jaw clenching will occur in humans as a response to stress exposure. The method for measuring reactions to stress involves a series of electrical recordings of the masseter and temporalis muscles. A high fixed-ratio response requirement in the first series of experiments shows that jaw clenching in humans occurs in situations analogous to those which produce biting in infrahuman subjects. In the second series, reduction in the amounts of money recieved by subjects is shown to cause increases in the jaw clench response and other negative effect motor behaviors. The third series demonstrates that perception of more favorable conditions existing for another person can increase anger and hostility in the subject.

  5. Quantum Tasks with Non-maximally Quantum Channels via Positive Operator-Valued Measurement

    NASA Astrophysics Data System (ADS)

    Peng, Jia-Yin; Luo, Ming-Xing; Mo, Zhi-Wen

    2013-01-01

    By using a proper positive operator-valued measure (POVM), we present two new schemes for probabilistic transmission with non-maximally four-particle cluster states. In the first scheme, we demonstrate that two non-maximally four-particle cluster states can be used to realize probabilistically sharing an unknown three-particle GHZ-type state within either distant agent's place. In the second protocol, we demonstrate that a non-maximally four-particle cluster state can be used to teleport an arbitrary unknown multi-particle state in a probabilistic manner with appropriate unitary operations and POVM. Moreover the total success probability of these two schemes are also worked out.

  6. Task Specific Frequencies of Neck Motion Measured in Healthy Young Adults over a 5 Day Period

    PubMed Central

    Cobian, Daniel G.; Sterling, Andrew C.; Anderson, Paul A.; Heiderscheit, Bryan C.

    2010-01-01

    Study Design Observational cohort design. Objective To quantify the frequencies and magnitudes of neck motion during daily activities in healthy subjects. Summary of Background Data Previous studies have measured the maximum excursions during re-created ADLs in lab settings, but there is a lack of information available on frequencies and excursions of neck motion with ADLs in non-artificial settings. Methods Ten healthy young adults were fitted with a portable motion measurement device that recorded movement about each primary axis. Participants were instructed to wear the unit continuously over a 5-day period and record their daily activities with corresponding times. After the collection period, subjects' activity logs were analyzed and data were partitioned into five categories which provided the most primary representation of ADLs: athletics, work, travel, sleep, and miscellaneous. Each category was further divided into increasingly specific activities (e.g. running and walking). Frequency of motions within 5° increments was determined and an hourly rate was calculated for each activity. Median motion about each axis for each activity was also determined. Results The total number of movements per hour for all axes, regardless of amplitude, was highest during athletic activity and lowest during sleeping. The majority of movements (92% of athletic activity, 90% of work) required less than 25° of lateral bending, while greater range of movement requirements were observed for flexion-extension and axial rotation. The median range of motion along all axes was highest for athletic activity and lowest for sleeping. Conclusions The results of this study provide a baseline of the frequency and magnitude of neck motion during normal ADLs for the specified population. These findings can assist physicians and physical therapists in determining the extent of disability and identifying activities that will likely be problematic for patients with limited cervical motion

  7. Measurement of phase gradients in the EEG.

    PubMed

    Alexander, D M; Trengove, C; Wright, J J; Boord, P R; Gordon, E

    2006-09-30

    Previous research has shown that spatio-temporal waves in the EEG are generally of long spatial wavelength and form smooth patterns of phase gradients at particular time-samples. This paper describes a method to measure smooth phase gradients of long spatial wavelength in the EEG. The method depends on the global pattern of phase at a given frequency and time and is therefore robust to variations, over time, in phase-lag between particular sites. Phases were estimated in the EEG signal using wavelet or short time-series Fourier methods. During an auditory oddball task, phases across the scalp tend to fall within a limited circular range, a range that is not indicative of phase-synchrony nor waves with multiple periods. At times the phases tended to maintain a spatially and temporally ordered relationship. The relative phases were analysed using three phase gradient basis functions, providing a measure of the amount of variance explained, across the electrodes, by smooth changes in relative phase from a single minimum or single maximum. The data from 586 adult subjects were analysed and it was found that the probability of phase gradient events varies with time and frequency in the stimulus-locked average, and with task demands. The temporal extent of spatio-temporal waves was measured by detecting smoothly changing patterns of phase latencies across the scalp. The specific spatial pattern and timing of phase gradients correspond closely to the latency distributions of certain ERPs. PMID:16574240

  8. The measurement of regional cerebral blood flow during the complex cognitive task of meditation: a preliminary SPECT study.

    PubMed

    Newberg, A; Alavi, A; Baime, M; Pourdehnad, M; Santanna, J; d'Aquili, E

    2001-04-10

    This study measured changes in regional cerebral blood flow (rCBF) during the complex cognitive task of meditation using single photon emission computed tomography. Eight experienced Tibetan Buddhist meditators were injected at baseline with 7 mCi HMPAO and scanned 20 min later for 45 min. The subjects then meditated for 1 h at which time they were injected with 25 mCi HMPAO and scanned 20 min later for 30 min. Values were obtained for regions of interest in major brain structures and normalized to whole brain activity. The percentage change between meditation and baseline was compared. Correlations between structures were also determined. Significantly increased rCBF (P<0.05) was observed in the cingulate gyrus, inferior and orbital frontal cortex, dorsolateral prefrontal cortex (DLPFC), and thalamus. The change in rCBF in the left DLPFC correlated negatively (P<0.05) with that in the left superior parietal lobe. Increased frontal rCBF may reflect focused concentration and thalamic increases overall increased cortical activity during meditation. The correlation between the DLPFC and the superior parietal lobe may reflect an altered sense of space experienced during meditation. These results suggest a complex rCBF pattern during the task of meditation.

  9. Behavioral and ERP measures of attentional bias to threat in the dot-probe task: poor reliability and lack of correlation with anxiety

    PubMed Central

    Kappenman, Emily S.; Farrens, Jaclyn L.; Luck, Steven J.; Proudfit, Greg Hajcak

    2014-01-01

    The dot-probe task is often considered a gold standard in the field for investigating attentional bias to threat. However, serious issues with the task have been raised. Specifically, a number of studies have demonstrated that the traditional reaction time (RT) measure of attentional bias to threat in the dot-probe task has poor internal reliability and poor test-retest reliability. In addition, although threatening stimuli capture attention in other paradigms, attentional bias to threat has not usually been found in typical research participants in the dot-probe task. However, when attention is measured in the dot-probe task with the N2pc component of the event-related potential waveform, substantial attentional orienting to threat is observed, and the internal reliability is moderate. To provide a rigorous comparison of the reliability of this N2pc measure and the conventional behavioral measure, as well as to examine the relationship of these measures to anxiety, the present study examined the N2pc in conjunction with RT in the dot-probe task in a large sample of participants (N = 96). As in previous studies, RT showed no bias to threatening images across the sample and exhibited poor internal reliability. Moreover, this measure did not relate to trait anxiety. By contrast, the N2pc revealed a significant initial shift of attention to threat, and this measure was internally reliable. However, the N2pc was not correlated with trait anxiety, indicating that it does not provide a meaningful index of individual differences in anxiety in the dot-probe task. Together, these results indicate a serious need to develop new tasks and methods to more reliably investigate attentional bias to threat and its relationship to anxiety in both clinical and non-clinical populations. PMID:25538644

  10. 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.

  11. The Virtual Tray of Objects Task as a novel method to electrophysiologically measure visuo-spatial recognition memory.

    PubMed

    Amico, Francesco; Ambrosini, Ettore; Guillem, François; Mento, Giovanni; Power, Dermot; Pergola, Giulio; Vallesi, Antonino

    2015-12-01

    We explored a novel method to electrophysiologically measure visuo-spatial recognition memory using a modified version of the Virtual Tray of Objects Task (VTOT). Event-related potentials (ERP) were recorded from 18 healthy volunteers during performance in the VTOT. Participants were required to detect random repetitions of three-dimensional visual stimuli (OLD) and to refrain from responding to non-repeated stimuli (NEW). Differences in ERP between the NEW and OLD conditions were tested for statistical significance using assumption-free non-parametric analyses. Further, a correlation between ERP and behavioral measures was sought. Significant OLD-NEW effects were found for four ERP components showing distinct spatio-temporal characteristics: a posterior positive component appearing at 100 ms (P100), a left-lateralized negative component peaking at ≈250 ms (N250), a frontal negative component at ≈300-450 ms (FN400), and a right late frontal negativity (rLFN) at ≈500-720 ms. Moreover, individual differences in the OLD-NEW effect computed for the rLFN positively correlated with repeated stimulus recognition efficiency. However, there were no late left parietal P600 old/new effects. These findings suggest that the P100 component might reflect early visual perception processes taking place during performance in the task, whereas the N250 and FN400 components could be linked to stimulus-dependent access to visual memory representations and familiarity-related processes, respectively. In contrast, we propose that the rLFN component could be associated with higher-level cognitive functions, such as attention and monitoring processes. Altogether, our results suggest that the ERP version of the VTOT could play a role in the electrophysiological assessment of visuo-spatial memory and related sub-processes. PMID:26546862

  12. Results of the second Round Robin on opening-load measurement conducted by ASTM Task Group E24.04.04 on crack closure measurement and analysis

    NASA Technical Reports Server (NTRS)

    Phillips, E. P.

    1993-01-01

    A second experimental Round Robin on the measurement of the crack opening load in fatigue crack growth tests has been completed by the ASTM Task Group E24.04.04 on Crack Closure Measurement and Analysis. Fourteen laboratories participated in the testing of aluminum alloy compact tension specimens. Opening-load measurements were made at three crack lengths during constant Delta K, constant stress ratio tests by most of the participants. Four participants made opening-load measurements during threshold tests. All opening-load measurements were based on the analysis of specimens compliance behavior, where the displacement/strain was measured either at the crack mouth or the mid-height back face location. The Round Robin data were analyzed for opening load using two non-subjective analysis methods: the compliance offset and the correlation coefficient methods. The scatter in the opening load results was significantly reduced when some of the results were excluded from the analysis population based on an accept/reject criterion for raw data quality. The compliance offset and correlation coefficient opening load analysis methods produced similar results for data populations that had been screened to eliminate poor quality data.

  13. Worth the ‘EEfRT’? The Effort Expenditure for Rewards Task as an Objective Measure of Motivation and Anhedonia

    PubMed Central

    Treadway, Michael T.; Buckholtz, Joshua W.; Schwartzman, Ashley N.; Lambert, Warren E.; Zald, David H.

    2009-01-01

    Background Of the putative psychopathological endophenotypes in major depressive disorder (MDD), the anhedonic subtype is particularly well supported. Anhedonia is generally assumed to reflect aberrant motivation and reward responsivity. However, research has been limited by a lack of objective measures of reward motivation. We present the Effort-Expenditure for Rewards Task (EEfRT or “effort”), a novel behavioral paradigm as a means of exploring effort-based decision-making in humans. Using the EEfRT, we test the hypothesis that effort-based decision-making is related to trait anhedonia. Methods/Results 61 undergraduate students participated in the experiment. Subjects completed self-report measures of mood and trait anhedonia, and completed the EEfRT. Across multiple analyses, we found a significant inverse relationship between anhedonia and willingness to expend effort for rewards. Conclusions These findings suggest that anhedonia is specifically associated with decreased motivation for rewards, and provide initial validation for the EEfRT as a laboratory-based behavioral measure of reward motivation and effort-based decision-making in humans. PMID:19672310

  14. Effects of Reliability and Global Context on Explicit and Implicit Measures of Sensed Hand Position in Cursor-Control Tasks

    PubMed Central

    Rand, Miya K.; Heuer, Herbert

    2016-01-01

    In a cursor-control task in which the motion of the cursor is rotated randomly relative to the movement of the hand, the sensed directions of hand and cursor are mutually biased. In our previous study, we used implicit and explicit measures of the bias of sensed hand direction toward the direction of the cursor and found different characteristics. The present study serves to explore further differences and commonalities of these measures. In Experiment 1, we examined the effects of different relative reliabilities of visual and proprioceptive information on the explicitly and implicitly assessed bias of sensed hand direction. In two conditions, participants made an aiming movement and returned to the start position immediately or after a delay of 6 s during which the cursor was no longer visible. The unimodal proprioceptive information on final hand position in the delayed condition served to increase its relative reliability. As a result, the bias of sensed hand direction toward the direction of the cursor was reduced for the explicit measure, with a complementary increase of the bias of sensed cursor direction, but unchanged for the implicit measure. In Experiment 2, we examined the influence of global context, specifically of the across-trial sequence of judgments of hand and cursor direction. Both explicitly and implicitly assessed biases of sensed hand direction did not significantly differ between the alternated condition (trial-to-trial alternations of judgments of hand and cursor direction) and the blocked condition (judgments of hand or cursor directions in all trials). They both substantially decreased from the alternated to the randomized condition (random sequence of judgments of hand and cursor direction), without a complementary increase of the bias of sensed cursor direction. We conclude that our explicit and implicit measures are equally sensitive to variations of coupling strength as induced by the variation of global context in Experiment 2, but

  15. Electrocortical and Behavioral Measures of Response Monitoring in Young Children During a Go/No-Go Task

    PubMed Central

    Torpey, Dana C.; Hajcak, Greg; Kim, Jiyon; Kujawa, Autumn; Klein, Daniel N.

    2012-01-01

    The current study examined behavioral measures and response-locked event-related brain potentials (ERPs) derived from a Go/No-Go task in a large (N = 328) sample of 5- to 7-year-olds in order to better understand the early development of response monitoring and the impact of child age and sex. In particular, the error-related negativity (ERN, defined on both error trials alone and the difference between error and correct trials, or ΔERN), correct response negativity (CRN), and error positivity (Pe) were examined. Overall, the ERN, CRN, and the Pe were spatially and temporally similar to those measured in adults and older children. Even within our narrow age range, older children were faster and more accurate; a more negative ΔERN and a more positive Pe were associated with: increasing age, increased accuracy, and faster reaction times on errors, suggesting these enhanced components reflected more efficient response monitoring of errors over development. Girls were slower and more accurate than boys, although both genders exhibited comparable ERPs. Younger children and girls were characterized by increased posterror slowing, although they did not demonstrate improved posterror accuracy. Posterror slowing was also related to a larger Pe and reduced posterror accuracy. Collectively, these data suggest that posterror slowing may be unrelated to cognitive control and may, like the Pe, reflect an orienting response to errors. PMID:21815136

  16. Measurements of electromagnetic properties of LCT (Large Coil Task) coils in IFSMTF (International Fusion Superconducting Magnet Test Facility)

    SciTech Connect

    Shen, S.S.; Baylor, L.R.; Dresner, L.; Fehling, D.T.; Lubell, M.S.; Lue, J.W.; Luton, J.N.; McManamy, T.J.; Wilson, C.T.; Wintenberg, R.E.

    1987-01-01

    Participants in the international Large Coil Task (LCT) have designed, built, and tested six different toroidal field coils. Each coil has a 2.5- by 3.5-m, D-shaped bore and a current between 10 and 18 kA and is designed to demonstrate stable operation at 8 T, with a superimposed averaged pulsed field of 0.14 T in 1.0 s and simulated nuclear heating. Testing of the full six-coil toroidal array began early in 1986 and was successfully completed on September 3, 1987, in the International Fusion Superconducting Magnet Test Facility (IFSMTF) at Oak Ridge National Laboratory (ORNL). This paper summarizes electromagnetic properties of LCT coils measured in different modes of energization and fast dump. Effects of mutual coupling and induced eddy currents are analyzed and discussed. Measurements of the ac loss caused by the superimposed pulsed fields are summarized. Finally, the interpretation of the test results and their relevance to practical fusion are presented. 11 refs., 10 figs., 4 tab.

  17. Time and Motion: Measuring the Effects of the Conceptual Demands of Tasks on Second Language Speech Production

    ERIC Educational Resources Information Center

    Robinson, Peter; Cadierno, Teresa; Shirai, Yasuhiro

    2009-01-01

    The Cognition Hypothesis (Robinson 2005) claims that pedagogic tasks should be sequenced for learners in an order of increasing cognitive complexity, and that along resource-directing dimensions of task demands increasing effort at conceptualization promotes more complex and grammaticized second language (L2) speech production. This article…

  18. Toward the Development of an Observation Measure of Interest and Attention for Literacy Tasks in Kindergarten Students

    ERIC Educational Resources Information Center

    Coughlan, Kelly A.

    2012-01-01

    Kindergarten students (N = 95) in three schools and seven classrooms were observed for on-task versus off-task behavior during three literacy instruction opportunities; small group instruction, whole group instruction and the less structured library setting over the 2011-2012 school year. Students' early literacy skills were assessed before…

  19. Optogenetics in Mice Performing a Visual Discrimination Task: Measurement and Suppression of Retinal Activation and the Resulting Behavioral Artifact

    PubMed Central

    Danskin, Bethanny; Denman, Daniel; Valley, Matthew; Ollerenshaw, Douglas; Williams, Derric; Groblewski, Peter; Reid, Clay; Olsen, Shawn; Waters, Jack

    2015-01-01

    Optogenetic techniques are used widely to perturb and interrogate neural circuits in behaving animals, but illumination can have additional effects, such as the activation of endogenous opsins in the retina. We found that illumination, delivered deep into the brain via an optical fiber, evoked a behavioral artifact in mice performing a visually guided discrimination task. Compared with blue (473 nm) and yellow (589 nm) illumination, red (640 nm) illumination evoked a greater behavioral artifact and more activity in the retina, the latter measured with electrical recordings. In the mouse, the sensitivity of retinal opsins declines steeply with wavelength across the visible spectrum, but propagation of light through brain tissue increases with wavelength. Our results suggest that poor retinal sensitivity to red light was overcome by relatively robust propagation of red light through brain tissue and stronger illumination of the retina by red than by blue or yellow light. Light adaptation of the retina, via an external source of illumination, suppressed retinal activation and the behavioral artifact without otherwise impacting behavioral performance. In summary, long wavelength optogenetic stimuli are particularly prone to evoke behavioral artifacts via activation of retinal opsins in the mouse, but light adaptation of the retina can provide a simple and effective mitigation of the artifact. PMID:26657323

  20. Optogenetics in Mice Performing a Visual Discrimination Task: Measurement and Suppression of Retinal Activation and the Resulting Behavioral Artifact.

    PubMed

    Danskin, Bethanny; Denman, Daniel; Valley, Matthew; Ollerenshaw, Douglas; Williams, Derric; Groblewski, Peter; Reid, Clay; Olsen, Shawn; Blanche, Timothy; Waters, Jack

    2015-01-01

    Optogenetic techniques are used widely to perturb and interrogate neural circuits in behaving animals, but illumination can have additional effects, such as the activation of endogenous opsins in the retina. We found that illumination, delivered deep into the brain via an optical fiber, evoked a behavioral artifact in mice performing a visually guided discrimination task. Compared with blue (473 nm) and yellow (589 nm) illumination, red (640 nm) illumination evoked a greater behavioral artifact and more activity in the retina, the latter measured with electrical recordings. In the mouse, the sensitivity of retinal opsins declines steeply with wavelength across the visible spectrum, but propagation of light through brain tissue increases with wavelength. Our results suggest that poor retinal sensitivity to red light was overcome by relatively robust propagation of red light through brain tissue and stronger illumination of the retina by red than by blue or yellow light. Light adaptation of the retina, via an external source of illumination, suppressed retinal activation and the behavioral artifact without otherwise impacting behavioral performance. In summary, long wavelength optogenetic stimuli are particularly prone to evoke behavioral artifacts via activation of retinal opsins in the mouse, but light adaptation of the retina can provide a simple and effective mitigation of the artifact.

  1. Measuring soccer technique with easy-to-administer field tasks in female soccer players from four different competitive levels.

    PubMed

    Pedersen, Arve Vorland; Lorås, Håvard; Norvang, Ole Petter; Asplund, Jennifer

    2014-12-01

    Soccer is a multidimensional sport that requires skills in many different domains. Reports from competitions at the highest levels around the world suggest that a particularly decisive performance factor is a team's technical execution. Testing of technical skills in soccer has been infrequent compared with testing of physiological variables, and there has been a lack of consensus as to which tasks should be included in test batteries. In this study, the validity of four field tasks (heading, long pass, juggling, and hit-the-post) was examined by testing 108 female soccer players from four different competitive levels, representing a hierarchy of skill levels. Correlation analysis indicated that the tasks' results appeared statistically unrelated (Spearman's ρ ≤ .36). Statistical comparisons across competitive levels showed that task performance was closely correlated with players' competition level, with regression analysis indicating that 92% of the variance in mean rankings across tasks could be explained by competitive level. As the easily administered and low-cost tasks identified differences in technical skills across competitive levels, such tasks appear valid for inclusion in tests of technical skills.

  2. Measuring soccer technique with easy-to-administer field tasks in female soccer players from four different competitive levels.

    PubMed

    Pedersen, Arve Vorland; Lorås, Håvard; Norvang, Ole Petter; Asplund, Jennifer

    2014-12-01

    Soccer is a multidimensional sport that requires skills in many different domains. Reports from competitions at the highest levels around the world suggest that a particularly decisive performance factor is a team's technical execution. Testing of technical skills in soccer has been infrequent compared with testing of physiological variables, and there has been a lack of consensus as to which tasks should be included in test batteries. In this study, the validity of four field tasks (heading, long pass, juggling, and hit-the-post) was examined by testing 108 female soccer players from four different competitive levels, representing a hierarchy of skill levels. Correlation analysis indicated that the tasks' results appeared statistically unrelated (Spearman's ρ ≤ .36). Statistical comparisons across competitive levels showed that task performance was closely correlated with players' competition level, with regression analysis indicating that 92% of the variance in mean rankings across tasks could be explained by competitive level. As the easily administered and low-cost tasks identified differences in technical skills across competitive levels, such tasks appear valid for inclusion in tests of technical skills. PMID:25456249

  3. Resting and task-modulated high-frequency brain rhythms measured by scalp encephalography in infants with tuberous sclerosis complex.

    PubMed

    Stamoulis, Catherine; Vogel-Farley, Vanessa; Degregorio, Geneva; Jeste, Shafali S; Nelson, Charles A

    2015-02-01

    The electrophysiological correlates of cognitive deficits in tuberous sclerosis complex (TSC) are not well understood, and modulations of neural dynamics by neuroanatomical abnormalities that characterize the disorder remain elusive. Neural oscillations (rhythms) are a fundamental aspect of brain function, and have dominant frequencies in a wide frequency range. The spatio-temporal dynamics of these frequencies in TSC are currently unknown. Using a novel signal decomposition approach this study investigated dominant cortical frequencies in 10 infants with TSC, in the age range 18-30 months, and 12 age-matched healthy controls. Distinct spectral characteristics were estimated in the two groups. High-frequency [in the high-gamma (>50 Hz) and ripple (>80 Hz) ranges], non-random EEG components were identified in both TSC and healthy infants at 18 months. Additional components in the lower gamma (30-50 Hz) ranges were also identified, with higher characteristic frequencies in TSC than in controls. Lower frequencies were statistically identical in both sub-groups. A significant shift in the high-frequency spectral content of the EEG was observed as a function of age, independently of task performance, possibly reflecting an overall maturation of developing neural circuits. This shift occurred earlier in healthy infants than in TSC, i.e., by age 20 months the highest dominant frequencies were in the high gamma range, whereas in TSC dominant frequencies above 100 Hz were still measurable. At age 28-30 months a statistically significant decrease in dominant high frequencies was observed in both TSC and healthy infants, possibly reflecting increased myelination and neuronal connection strengthening with age. Although based on small samples, and thus preliminary, the findings in this study suggest that dominant cortical rhythms, a fundamental aspect of neurodynamics, may be affected in TSC, possibly leading to impaired information processing in the brain.

  4. Resting and Task-Modulated High-Frequency Brain Rhythms Measured by Scalp Encephalography in Infants with Tuberous Sclerosis Complex

    PubMed Central

    Stamoulis, Catherine; Vogel-Farley, Vanessa; Degregorio, Geneva; Jeste, Shafali S.; Nelson, Charles A.

    2013-01-01

    The electrophysiological correlates of cognitive deficits in Tuberous Sclerosis Complex (TSC) are not well understood, and modulations of neural dynamics by neuroanatomical abnormalities that characterize the disorder remain elusive. Neural oscillations (rhythms) are a fundamental aspect of brain function, and have dominant frequencies in a wide frequency range. The spatio-temporal dynamics of these frequencies in TSC are currently unknown. Using a novel signal decomposition approach this study investigated dominant cortical frequencies in 10 infants with TSC, in the age range 18–30 months, and 12 age-matched healthy controls. Distinct spectral characteristics were estimated in the two groups. High-frequency (in the high-gamma (>50 Hz) and ripple (>80 Hz) ranges), non-random EEG components were identified in both TSC and healthy infants at 18 months. Additional components in the lower gamma (30–50 Hz) ranges were also identified, with higher characteristic frequencies in TSC than in controls. Lower frequencies were statistically identical in both sub-groups. A significant shift in the high-frequency spectral content of the EEG was observed as a function of age, independently of task performance, possibly reflecting an overall maturation of developing neural circuits. This shift occurred earlier in healthy infants than in TSC, i.e., by age 20 months the highest dominant frequencies were in the high gamma range, whereas in TSC dominant frequencies above 100 Hz were still measurable. At age 28–30 months a statistically significant decrease in dominant high frequencies was observed in both TSC and healthy infants, possibly reflecting increased myelination and neuronal connection strengthening with age. Although based on small samples, and thus preliminary, the findings in this study suggest that dominant cortical rhythms, a fundamental aspect of neurodynamics, may be affected in TSC, possibly leading to impaired information processing in the brain. PMID:23838730

  5. Analysis of schizophrenia-related genes and electrophysiological measures reveals ZNF804A association with amplitude of P300b elicited by novel sounds

    PubMed Central

    del Re, E C; Bergen, S E; Mesholam-Gately, R I; Niznikiewicz, M A; Goldstein, J M; Woo, T U; Shenton, M E; Seidman, L J; McCarley, R W; Petryshen, T L

    2014-01-01

    Several genes have recently been identified as risk factors for schizophrenia (SZ) by genome-wide association studies (GWAS), including ZNF804A which is thought to function in transcriptional regulation. However, the downstream pathophysiological changes that these genes confer remain to be elucidated. In 143 subjects (68 clinical high risk, first episode or chronic cases; 75 controls), we examined the association between 21 genetic markers previously identified by SZ GWAS or associated with putative intermediate phenotypes of SZ against three event-related potential (ERP) measures: mismatch negativity (MMN), amplitude of P300 during an auditory oddball task, and P300 amplitude during an auditory novelty oddball task. Controlling for age and sex, significant genetic association surpassing Bonferroni correction was detected between ZNF804A marker rs1344706 and P300 amplitude elicited by novel sounds (beta=4.38, P=1.03 × 10−4), which is thought to index orienting of attention to unexpected, salient stimuli. Subsequent analyses revealed that the association was driven by the control subjects (beta=6.35, P=9.08 × 10−5), and that the risk allele was correlated with higher novel P300b amplitude, in contrast to the significantly lower amplitude observed in cases compared to controls. Novel P300b amplitude was significantly correlated with a neurocognitive measure of auditory attention under interference conditions, suggesting a relationship between novel P300b amplitude and higher-order attentional processes. Our results suggest pleiotropic effects of ZNF804A on risk for SZ and neural mechanisms that are indexed by the novel P300b ERP component. PMID:24424392

  6. Comparisons of an open-ended vs. forced-choice 'mind reading' task: implications for measuring perspective-taking and emotion recognition.

    PubMed

    Cassels, Tracy G; Birch, Susan A J

    2014-01-01

    Perspective-taking and emotion recognition are essential for successful social development and have been the focus of developmental research for many years. Although the two abilities often overlap, they are distinct and our understanding of these abilities critically rests upon the efficacy of existing measures. Lessons from the literature differentiating recall versus recognition memory tasks led us to hypothesize that an open-ended emotion recognition measure would be less reliant on compensatory strategies and hence a more specific measure of emotion recognition abilities than a forced-choice task. To this end, we compared an open-ended version of the Reading the Mind in the Eyes Task with the original forced-choice version in two studies: 118 typically-developing 4- to 8-year-olds (Study 1) and 139 5- to 12-year-olds; 85 typically-developing and 54 with learning disorders (Study 2). We found that the open-ended version of the task was a better predictor of empathy and more reliably discriminated typically-developing children from those with learning disorders. As a whole, the results suggest that the open-ended version is a more sensitive measure of emotion recognition specifically.

  7. Measuring the Cool Tool as a Targeted Intervention to Minimize Teacher Reprimands and Students' On-Task Behaviors in an Urban Elementary School

    ERIC Educational Resources Information Center

    Utley, Cheryl A.; Obiakor, Festus E.

    2015-01-01

    This study measured the effects of a targeted intervention, The Cool Tool, implemented in the secondary prevention tier to minimize teacher reprimands and students' on-task behaviors in an urban elementary school. The participants in the social skills intervention programs were seven teachers, across grades K-5. Assessments included pre-posttest…

  8. Older Women's Development: A Comparison of Women in Their 60s and 80s on a Measure of Erikson's Developmental Tasks.

    ERIC Educational Resources Information Center

    Norman, Suzanne M.; McCluskey-Fawcett, Kathleen; Ashcraft, Lisa

    2002-01-01

    Compares women from two ages groups in order to understand their development across the life span. Measures of Psychosocial Development, which assesses Erikson's developmental stages, were administered to 41 women in 2 cohorts (ages 60-70, ages 80-90). Age group differences in the resolution of Erikson's identity and trust developmental tasks were…

  9. The Development and Evaluation of an Achievement Test for Measuring the Efficacy of Task-Based Writing Activities to Enhance Iranian EFL Learners' Reading Comprehension

    ERIC Educational Resources Information Center

    Nejad, Ferdows Mohsen; Khosravian, Fereshteh

    2014-01-01

    The present study examined the reliability of an achievement test to measure the efficacy of task-based writing activities to improve Iranian EFL learners' reading comprehension at the intermediate level in a private language institute in Ilam, Iran, namely Alefba language institute. To achieve the goal, the techniques for evaluating reliability…

  10. Psychophysiological Correlates of Sexually and Non-Sexually Motivated Attention to Film Clips in a Workload Task

    PubMed Central

    Carvalho, Sandra; Leite, Jorge; Galdo-Álvarez, Santiago; Gonçalves, Óscar F.

    2011-01-01

    Some authors have speculated that the cognitive component (P3) of the Event-Related Potential (ERP) can function as a psychophysiological measure of sexual interest. The aim of this study was to determine if the P3 ERP component in a workload task can be used as a specific and objective measure of sexual motivation by comparing the neurophysiologic response to stimuli of motivational relevance with different levels of valence and arousal. A total of 30 healthy volunteers watched different films clips with erotic, horror, social-positive and social-negative content, while answering an auditory oddball paradigm. Erotic film clips resulted in larger interference when compared to both the social-positive and auditory alone conditions. Horror film clips resulted in the highest levels of interference with smaller P3 amplitudes than erotic and also than social-positive, social-negative and auditory alone condition. No gender differences were found. Both horror and erotic film clips significantly decreased heart rate (HR) when compared to both social-positive and social-negative films. The erotic film clips significantly increased the skin conductance level (SCL) compared to the social-negative films. The horror film clips significantly increased the SCL compared to both social-positive and social-negative films. Both the highly arousing erotic and non-erotic (horror) movies produced the largest decrease in the P3 amplitude, a decrease in the HR and an increase in the SCL. These data support the notion that this workload task is very sensitive to the attentional resources allocated to the film clip, although they do not act as a specific index of sexual interest. Therefore, the use of this methodology seems to be of questionable utility as a specific measure of sexual interest or as an objective measure of the severity of Hypoactive Sexual Desire Disorder. PMID:22216305

  11. Psychophysiological correlates of sexually and non-sexually motivated attention to film clips in a workload task.

    PubMed

    Carvalho, Sandra; Leite, Jorge; Galdo-Álvarez, Santiago; Gonçalves, Oscar F

    2011-01-01

    Some authors have speculated that the cognitive component (P3) of the Event-Related Potential (ERP) can function as a psychophysiological measure of sexual interest. The aim of this study was to determine if the P3 ERP component in a workload task can be used as a specific and objective measure of sexual motivation by comparing the neurophysiologic response to stimuli of motivational relevance with different levels of valence and arousal. A total of 30 healthy volunteers watched different films clips with erotic, horror, social-positive and social-negative content, while answering an auditory oddball paradigm. Erotic film clips resulted in larger interference when compared to both the social-positive and auditory alone conditions. Horror film clips resulted in the highest levels of interference with smaller P3 amplitudes than erotic and also than social-positive, social-negative and auditory alone condition. No gender differences were found. Both horror and erotic film clips significantly decreased heart rate (HR) when compared to both social-positive and social-negative films. The erotic film clips significantly increased the skin conductance level (SCL) compared to the social-negative films. The horror film clips significantly increased the SCL compared to both social-positive and social-negative films. Both the highly arousing erotic and non-erotic (horror) movies produced the largest decrease in the P3 amplitude, a decrease in the HR and an increase in the SCL. These data support the notion that this workload task is very sensitive to the attentional resources allocated to the film clip, although they do not act as a specific index of sexual interest. Therefore, the use of this methodology seems to be of questionable utility as a specific measure of sexual interest or as an objective measure of the severity of Hypoactive Sexual Desire Disorder.

  12. Psychophysiological correlates of sexually and non-sexually motivated attention to film clips in a workload task.

    PubMed

    Carvalho, Sandra; Leite, Jorge; Galdo-Álvarez, Santiago; Gonçalves, Oscar F

    2011-01-01

    Some authors have speculated that the cognitive component (P3) of the Event-Related Potential (ERP) can function as a psychophysiological measure of sexual interest. The aim of this study was to determine if the P3 ERP component in a workload task can be used as a specific and objective measure of sexual motivation by comparing the neurophysiologic response to stimuli of motivational relevance with different levels of valence and arousal. A total of 30 healthy volunteers watched different films clips with erotic, horror, social-positive and social-negative content, while answering an auditory oddball paradigm. Erotic film clips resulted in larger interference when compared to both the social-positive and auditory alone conditions. Horror film clips resulted in the highest levels of interference with smaller P3 amplitudes than erotic and also than social-positive, social-negative and auditory alone condition. No gender differences were found. Both horror and erotic film clips significantly decreased heart rate (HR) when compared to both social-positive and social-negative films. The erotic film clips significantly increased the skin conductance level (SCL) compared to the social-negative films. The horror film clips significantly increased the SCL compared to both social-positive and social-negative films. Both the highly arousing erotic and non-erotic (horror) movies produced the largest decrease in the P3 amplitude, a decrease in the HR and an increase in the SCL. These data support the notion that this workload task is very sensitive to the attentional resources allocated to the film clip, although they do not act as a specific index of sexual interest. Therefore, the use of this methodology seems to be of questionable utility as a specific measure of sexual interest or as an objective measure of the severity of Hypoactive Sexual Desire Disorder. PMID:22216305

  13. Calculations of two new dose metrics proposed by AAPM Task Group 111 using the measurements with standard CT dosimetry phantoms

    SciTech Connect

    Li, Xinhua; Zhang, Da; Liu, Bob

    2013-08-15

    Purpose: AAPM Task Group 111 proposed to measure the equilibrium dose-pitch product D-caret{sub eq} for scan modes involving table translation and the midpoint dose D{sub L}(0) for stationary-table modes on the central and peripheral axes of sufficiently long (e.g., at least 40 cm) phantoms. This paper presents an alternative approach to calculate both metrics using the measurements of scanning the standard computed tomographic (CT) dosimetry phantoms on CT scanners.Methods: D-caret{sub eq} was calculated from CTDI{sub 100} and ε(CTDI{sub 100}) (CTDI{sub 100} efficiency), and D{sub L}(0) was calculated from D-caret{sub eq} and the approach to equilibrium function H(L) =D{sub L}(0)/D{sub eq}, where D{sub eq} was the equilibrium dose. CTDI{sub 100} may be directly obtained from several sources (such as medical physicist's CT scanner performance evaluation or the IMPACT CT patient dosimetry calculator), or be derived from CTDI{sub Vol} using the central to peripheral CTDI{sub 100} ratio (R{sub 100}). The authors have provided the required ε(CTDI{sub 100}) and H(L) data in two previous papers [X. Li, D. Zhang, and B. Liu, Med. Phys. 39, 901–905 (2012); and ibid. 40, 031903 (10pp.) (2013)]. R{sub 100} was assessed for a series of GE, Siemens, Philips, and Toshiba CT scanners with multiple settings of scan field of view, tube voltage, and bowtie filter.Results: The calculated D{sub L}(0) and D{sub L}(0)/D{sub eq} in PMMA and water cylinders were consistent with the measurements on two GE CT scanners (LightSpeed 16 and VCT) by Dixon and Ballard [Med. Phys. 34, 3399–3413 (2007)], the measurements on a Siemens CT scanner (SOMATOM Spirit Power) by Descamps et al. [J. Appl. Clin. Med. Phys. 13, 293–302 (2012)], and the Monte Carlo simulations by Boone [Med. Phys. 36, 4547–4554 (2009)].Conclusions: D-caret{sub eq} and D{sub L}(0) can be calculated using the alternative approach. The authors have provided the required ε(CTDI{sub 100}) and H(L) data in two previous

  14. Effect of Posttraumatic Stress on Study Time in a Task Measuring Four Component Processes Underlying Text-Level Reading

    ERIC Educational Resources Information Center

    Sullivan, Michael P.; Griffiths, Gina G.; Sohlberg, Mckay Moore

    2014-01-01

    Purpose: To investigate the effect of combat-related posttraumatic stress disorder (PTSD) on 4 components underlying text-level reading comprehension. Method: A group of 17 veterans with PTSD and 17 matched control participants took part. An experimental task required participants to read and study 3-sentence paragraphs describing semantic…

  15. Knowledge on Accelerated Motion as Measured by Implicit and Explicit Tasks in 5 to 16 Year Olds

    ERIC Educational Resources Information Center

    Ebersbach, Mirjam; Van Dooren, Wim; Verschaffel, Lieven

    2011-01-01

    The present study aimed at investigating children's and adolescents' understanding of constant and accelerated motions. The main objectives were (1) to investigate whether different task formats would affect the performance and (2) to track developmental changes in this domain. Five to 16 year olds (N = 157) predicted the distances of a moving…

  16. Differential processing of natural scenes in posterior cortical atrophy and in Alzheimer's disease, as measured with a saccade choice task.

    PubMed

    Boucart, Muriel; Calais, Gauthier; Lenoble, Quentin; Moroni, Christine; Pasquier, Florence

    2014-01-01

    Atrophy of the medial temporal lobe structures that support scene perception and the binding of an object to its context (i.e., the hippocampus and the parahippocampal cortex) appears early in the course of Alzheimer's disease (AD). However, few studies have investigated scene perception in people with AD. Here, we assessed the ability to find a target object within a natural scene in people with AD and in people with posterior cortical atrophy (PCA, a variant of AD). Pairs of color photographs were displayed on the left and right of a fixation cross for 1 s. In separate blocks of trials, participants were asked to categorize the target (an animal) by either moving their eyes toward the photograph containing the target (the saccadic choice task) or pressing a key corresponding to the target's location (the manual choice task). Isolated objects and objects within scenes were studied in both tasks. Participants with PCA were more impaired in detection of a target within a scene than participants with AD. The latter's performance pattern was more similar to that of age-matched controls in terms of accuracy, saccade latencies and the benefit gained from contextual information. Participants with PCA benefited less from contextual information in both the saccade and the manual choice tasks-suggesting that people with posterior brain lesions have impairments in figure/ground segregation and are more sensitive to object crowding. PMID:25120440

  17. The Measurement of Executive Function at Age 3 Years: Psychometric Properties and Criterion Validity of a New Battery of Tasks

    ERIC Educational Resources Information Center

    Willoughby, Michael T.; Blair, Clancy B.; Wirth, R. J.; Greenberg, Mark

    2010-01-01

    In this study, the authors examined the psychometric properties and criterion validity of a newly developed battery of tasks that were designed to assess executive function (EF) abilities in early childhood. The battery was included in the 36-month assessment of the Family Life Project (FLP), a prospective longitudinal study of 1,292 children…

  18. Novel Modeling of Task vs. Rest Brain State Predictability Using a Dynamic Time Warping Spectrum: Comparisons and Contrasts with Other Standard Measures of Brain Dynamics

    PubMed Central

    Dinov, Martin; Lorenz, Romy; Scott, Gregory; Sharp, David J.; Fagerholm, Erik D.; Leech, Robert

    2016-01-01

    Dynamic time warping, or DTW, is a powerful and domain-general sequence alignment method for computing a similarity measure. Such dynamic programming-based techniques like DTW are now the backbone and driver of most bioinformatics methods and discoveries. In neuroscience it has had far less use, though this has begun to change. We wanted to explore new ways of applying DTW, not simply as a measure with which to cluster or compare similarity between features but in a conceptually different way. We have used DTW to provide a more interpretable spectral description of the data, compared to standard approaches such as the Fourier and related transforms. The DTW approach and standard discrete Fourier transform (DFT) are assessed against benchmark measures of neural dynamics. These include EEG microstates, EEG avalanches, and the sum squared error (SSE) from a multilayer perceptron (MLP) prediction of the EEG time series, and simultaneously acquired FMRI BOLD signal. We explored the relationships between these variables of interest in an EEG-FMRI dataset acquired during a standard cognitive task, which allowed us to explore how DTW differentially performs in different task settings. We found that despite strong correlations between DTW and DFT-spectra, DTW was a better predictor for almost every measure of brain dynamics. Using these DTW measures, we show that predictability is almost always higher in task than in rest states, which is consistent to other theoretical and empirical findings, providing additional evidence for the utility of the DTW approach. PMID:27242502

  19. Novel Modeling of Task vs. Rest Brain State Predictability Using a Dynamic Time Warping Spectrum: Comparisons and Contrasts with Other Standard Measures of Brain Dynamics.

    PubMed

    Dinov, Martin; Lorenz, Romy; Scott, Gregory; Sharp, David J; Fagerholm, Erik D; Leech, Robert

    2016-01-01

    Dynamic time warping, or DTW, is a powerful and domain-general sequence alignment method for computing a similarity measure. Such dynamic programming-based techniques like DTW are now the backbone and driver of most bioinformatics methods and discoveries. In neuroscience it has had far less use, though this has begun to change. We wanted to explore new ways of applying DTW, not simply as a measure with which to cluster or compare similarity between features but in a conceptually different way. We have used DTW to provide a more interpretable spectral description of the data, compared to standard approaches such as the Fourier and related transforms. The DTW approach and standard discrete Fourier transform (DFT) are assessed against benchmark measures of neural dynamics. These include EEG microstates, EEG avalanches, and the sum squared error (SSE) from a multilayer perceptron (MLP) prediction of the EEG time series, and simultaneously acquired FMRI BOLD signal. We explored the relationships between these variables of interest in an EEG-FMRI dataset acquired during a standard cognitive task, which allowed us to explore how DTW differentially performs in different task settings. We found that despite strong correlations between DTW and DFT-spectra, DTW was a better predictor for almost every measure of brain dynamics. Using these DTW measures, we show that predictability is almost always higher in task than in rest states, which is consistent to other theoretical and empirical findings, providing additional evidence for the utility of the DTW approach. PMID:27242502

  20. Response competition and response inhibition during different choice-discrimination tasks: evidence from ERP measured inside MRI scanner.

    PubMed

    Gonzalez-Rosa, Javier J; Inuggi, Alberto; Blasi, Valeria; Cursi, Marco; Annovazzi, Pietro; Comi, Giancarlo; Falini, Andrea; Leocani, Letizia

    2013-07-01

    We investigated the neural correlates underlying response inhibition and conflict detection processes using ERPs and source localization analyses simultaneously acquired during fMRI scanning. ERPs were elicited by a simple reaction time task (SRT), a Go/NoGo task, and a Stroop-like task (CST). The cognitive conflict was thus manipulated in order to probe the degree to which information processing is shared across cognitive systems. We proposed to dissociate inhibition and interference conflict effects on brain activity by using identical Stroop-like congruent/incongruent stimuli in all three task contexts and while varying the response required. NoGo-incongruent trials showed a larger N2 and enhanced activations of rostral anterior cingulate cortex (ACC) and pre-supplementary motor area, whereas Go-congruent trials showed a larger P3 and increased parietal activations. Congruent and incongruent conditions of the CST task also elicited similar N2, P3 and late negativity (LN) ERPs, though CST-incongruent trials revealed a larger LN and enhanced prefrontal and ACC activations. Considering the stimulus probability and experimental manipulation of our study, current findings suggest that NoGo N2 and frontal NoGo P3 appear to be more associated to response inhibition rather than a specific conflict monitoring, whereas occipito-parietal P3 of Go and CST conditions may be more linked to a planned response competition between the prepared and required response. LN, however, appears to be related to higher level conflict monitoring associated with response choice-discrimination but not when the presence of cognitive conflict is associated with response inhibition.

  1. P300-based Stroop study with low probability and target Stroop oddballs: the evidence still favors the response selection hypothesis.

    PubMed

    Rosenfeld, J Peter; Skogsberg, Katieann R

    2006-06-01

    This paper addresses the issue of the locus of action in cognitive processing during Stroop effects. It uses the P300 latency to assess stimulus processing effects, but, for the first time, under conditions in which Stroop stimuli are rare and target stimuli. The study was also concerned with demonstrating that apparent P300s during verbal responding are in fact uninterpretable due to contamination of EEG by speech-related artifact. Three studies were presented. In Study 1, there were 3 blocks, each containing 1 of 3 types of rare Stroop stimuli (p = .15), congruent, neutral, and incongruent. There were also 3 response modes: button press (BUTTON), speaking aloud (VERBAL), and speaking to self (SILENT). Three sessions were used, each for a different response style. The only task was to name the color on each trial. In the 2 non-verbal blocks, Reaction Time (RT) varied by stimulus type; congruent < neutral < incongruent. P300 latency was the same across blocks in these non-verbal conditions in which one saw the classic Pz > Cz > Fz distribution. The much larger, speech artifact-contaminated "P300s" in the VERBAL blocks did suggest a Stroop effect, especially at Fz and Cz, where "P300s" were larger than at Pz. In Study 2, there were 2 response modes, VERBAL and SILENT, and only two rare Stroop stimuli; neutral and incongruent, 1 per block. In each of these blocks, one word-color combination was a designated target requiring a unique response. The subject was to name the color followed by a yes or no to categorize the target or non-target. Again the RT for incongruents was greater than RT for neutrals, without a parallel effect in P300 latency. Again, the rostral ERPs appeared artifactual in the VERBAL condition. Study 3 was a replication of the second study, except that motivated subjects, versus Psychology pool recruits, were used. The latency-RT correlation still failed to obtain. Thus, using classic P300-eliciting antecedents-rare and target (Stroop) stimuli

  2. Implicit and explicit measurements of sexual preference in gay and heterosexual men: a comparison of priming techniques and the implicit association task.

    PubMed

    Snowden, Robert J; Wichter, Jan; Gray, Nicola S

    2008-08-01

    The present study examined how well implicit measures were able to predict sexual orientation. Most previous research in the sexual orientation domain has been dependent upon self-report, which requires explicit, conscious awareness of sexual orientation and/or erotic preferences. On the other hand, implicit measurements are thought to be able to reflect immediate automatic reactions that may not be available to introspection. A total of 50 heterosexual and 25 homosexual men completed two implicit measures: the Implicit Association Task (IAT) and the Priming Task (PT). Sexual orientation was determined by self-report. In the PT, participants classified words as either sexually attractive or unattractive. Each word was preceded by a "prime" that was a picture of either a male or a female. The IAT consisted of classifying these same words as sexually attractive or unattractive, and classifying the pictures as either male or female. Both the IAT and the PT had very good ability to predict sexual orientation with Area Under the Curves (AUC) of 0.97 and 0.86, respectively. Unlike many other reports of implicit measures of behavior, the IAT and the PT correlated strongly with each other, and also with the explicit measurements of sexual orientation. It was concluded that these implicit measures can provide a valuable tool for research into sexual orientation and erotic preference that can complement existing measures, such as self-report questionnaires and physiological changes in sexual arousal in response to erotic stimuli. PMID:17333326

  3. Recall initiation strategies must be controlled in training studies that use immediate free recall tasks to measure the components of working memory capacity across time.

    PubMed

    Gibson, Bradley S; Gondoli, Dawn M; Johnson, Ann C; Robison, Matthew K

    2014-01-01

    There has been great interest in using working memory (WM) training regimens as an alternative treatment for ADHD, but it has recently been concluded that existing training regimens may not be optimally designed because they target the primary memory component but not the secondary component of WM capacity. This conclusion requires the ability to accurately measure changes in primary and secondary memory abilities over time. The immediate free recall task has been used in previous studies to measure these changes; however, one concern with these tasks is that the recall order required on training exercises may influence the recall strategy used during free recall, which may in turn influence the relative number of items recalled from primary and secondary memory. To address this issue, previous training studies have explicitly controlled recall strategy before and after training. However, the necessity of controlling for recall strategies has not been explicitly tested. The present study investigated the effects of forward-serial-order training on free recall performance under conditions in which recall strategy was not controlled using a sample of adolescents with ADHD. Unlike when recall order was controlled, the main findings showed selective improvement of the secondary memory component (as opposed to the primary memory component) when recall order was uncontrolled. This finding advances our understanding of WM training by highlighting the importance of controlling for recall strategies when free recall tasks are used to measure changes in the primary and secondary components of WM across time.

  4. Spatial release of cognitive load measured in a dual-task paradigm in normal-hearing and hearing-impaired listeners.

    PubMed

    Xia, Jing; Nooraei, Nazanin; Kalluri, Sridhar; Edwards, Brent

    2015-04-01

    This study investigated whether spatial separation between talkers helps reduce cognitive processing load, and how hearing impairment interacts with the cognitive load of individuals listening in multi-talker environments. A dual-task paradigm was used in which performance on a secondary task (visual tracking) served as a measure of the cognitive load imposed by a speech recognition task. Visual tracking performance was measured under four conditions in which the target and the interferers were distinguished by (1) gender and spatial location, (2) gender only, (3) spatial location only, and (4) neither gender nor spatial location. Results showed that when gender cues were available, a 15° spatial separation between talkers reduced the cognitive load of listening even though it did not provide further improvement in speech recognition (Experiment I). Compared to normal-hearing listeners, large individual variability in spatial release of cognitive load was observed among hearing-impaired listeners. Cognitive load was lower when talkers were spatially separated by 60° than when talkers were of different genders, even though speech recognition was comparable in these two conditions (Experiment II). These results suggest that a measure of cognitive load might provide valuable insight into the benefit of spatial cues in multi-talker environments. PMID:25920841

  5. Task breakdown

    NASA Technical Reports Server (NTRS)

    Pavlich, Jane

    1990-01-01

    The topics concerning the Center for Space Construction (CSC) space construction breakdown structure are presented in viewgraph form. It is concluded that four components describe a task -- effecting, information gathering, analysis, and regulation; uncertainties effect the relative amount of information gathering and analysis that occurs; and that task timing requirements drive the 'location in time' of cognition.

  6. EEG delta oscillations index inhibitory control of contextual novelty to both irrelevant distracters and relevant task-switch cues.

    PubMed

    Prada, Laura; Barceló, Francisco; Herrmann, Christoph S; Escera, Carles

    2014-07-01

    Delta oscillations contribute to the human P300 event-related potential evoked by oddball targets, although it is unclear whether they index contextual novelty (event oddballness, novelty P3, nP3), or target-related processes (event targetness, target P3b). To examine this question, the electroencephalogram (EEG) was recorded during a cued task-switching version of the Wisconsin card-sorting test. Each target card was announced by a tone cueing either to switch or repeat the task. Novel sound distracters were interspersed among trials. Time-frequency EEG analyses revealed bursts of delta (2-4 Hz) power associated with enhanced nP3 amplitudes to both task-switch cues and novel distracters-but no association with target P3b. These findings indicate that the P300-delta response indexes contextual novelty regardless of whether novelty emanates from endogenous (new task rules) or exogenous (novel distracters) sources of information. PMID:24673586

  7. Time-Frequency Theta and Delta Measures Index Separable Components of Feedback Processing in a Gambling Task

    PubMed Central

    Bernat, Edward M.; Nelson, Lindsay D.; Baskin-Sommers, Arielle R.

    2014-01-01

    Previous work using gambling tasks indicate that the feedback negativity (FN) reflects primary or salient stimulus attributes (often gain vs. loss), whereas the feedback-P300 appears sensitive to secondary stimulus information. A recent time-frequency approach has characterized separable theta (3–7 Hz) and delta (0–3 Hz) feedback processes, independently sensitive to primary feedback attributes, specifically loss and gain outcomes respectively (Bernat et al., 2011). The current study extends this time-frequency work to evaluate both primary and secondary (relative outcome and outcome magnitude) feedback attributes. Consistent with previous reports, theta indexed an initial, lower-level response sensitive to the primary (most salient) feedback attributes (specifically losses), while delta was sensitive to both primary attributes (specifically gains) and assessed secondary stimulus features. PMID:25581491

  8. Informational Masking in Normal-Hearing and Hearing-Impaired Listeners Measured in a Nonspeech Pattern Identification Task

    PubMed Central

    Best, Virginia; Mason, Christine R.; Swaminathan, Jayaganesh; Kidd, Gerald

    2016-01-01

    Individuals with sensorineural hearing loss (SNHL) often experience more difficulty with listening in multisource environments than do normal-hearing (NH) listeners. While the peripheral effects of sensorineural hearing loss certainly contribute to this difficulty, differences in central processing of auditory information may also contribute. To explore this issue, it is important to account for peripheral differences between NH and these hearing-impaired (HI) listeners so that central effects in multisource listening can be examined. In the present study, NH and HI listeners performed a tonal pattern identification task at two distant center frequencies (CFs), 850 and 3500 Hz. In an attempt to control for differences in the peripheral representations of the stimuli, the patterns were presented at the same sensation level (15 dB SL), and the frequency deviation of the tones comprising the patterns was adjusted to obtain equal quiet pattern identification performance across all listeners at both CFs. Tonal sequences were then presented at both CFs simultaneously (informational masking conditions), and listeners were asked either to selectively attend to a source (CF) or to divide attention between CFs and identify the pattern at a CF designated after each trial. There were large differences between groups in the frequency deviations necessary to perform the pattern identification task. After compensating for these differences, there were small differences between NH and HI listeners in the informational masking conditions. HI listeners showed slightly greater performance asymmetry between the low and high CFs than did NH listeners, possibly due to central differences in frequency weighting between groups. PMID:27059627

  9. Oncology Section EDGE Task Force on Prostate Cancer: A Systematic Review of Outcome Measures for Health-Related Quality of Life

    PubMed Central

    Harrington, Shana; Lee, Jeannette; Colon, Genevieve; Alappattu, Meryl

    2016-01-01

    Background Health-related quality of life (HRQOL) is multidimensional and subjective, encompassing occupational and physical function, psychological state, social interaction, and somatic sensation. Because of the wide scope of HRQOL and its implications for the medical management of prostate cancer survivors, clinicians and researchers need to know the most reliable and valid measures currently available for addressing this clinical construct in men diagnosed with prostate cancer. Purpose To identify and evaluate patient-reported outcome measures used to assess HRQOL in men diagnosed with prostate cancer and make recommendations for the use of these patient-reported outcome measures in both the research and clinic settings. Methods The literature was systematically reviewed for patient-reported outcome measures used in peer-reviewed, published research to assess HRQOL in men diagnosed with prostate cancer. The goals were to examine the psychometric properties of commonly used HRQOL measures in order to determine their clinical utility. Results The following patient-reported outcome measures are highly recommended by the Task Force to assess HRQOL in men diagnosed with prostate cancer: EORTC QLQ-P25 (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire–Prostate 25), EPIC (Expanded Prostate Cancer Index Composite), FACT-P (Functional Assessment of Cancer Therapy–Prostate), UCLA-PCI (UCLA–Prostate Cancer Index), EORTC QLQ-C30 (EORTC Quality of Life Questionnaire–Cancer 30), FACT-G (Functional Assessment of Cancer Therapy–General), and SF (Short-Form) 36, 12, and 8. Conclusions A variety of patient-reported outcome measures have been reported in the literature to assess HRQOL in men diagnosed with prostate cancer. Seven measures were found to have satisfactory psychometric properties, as well as good clinical utility, and are recommended for use by the researchers on this Task Force. PMID:27134804

  10. Snap Your Fingers! An ERP/sLORETA Study Investigating Implicit Processing of Self- vs. Other-Related Movement Sounds Using the Passive Oddball Paradigm

    PubMed Central

    Justen, Christoph; Herbert, Cornelia

    2016-01-01

    So far, neurophysiological studies have investigated implicit and explicit self-related processing particularly for self-related stimuli such as the own face or name. The present study extends previous research to the implicit processing of self-related movement sounds and explores their spatio-temporal dynamics. Event-related potentials (ERPs) were assessed while participants (N = 12 healthy subjects) listened passively to previously recorded self- and other-related finger snapping sounds, presented either as deviants or standards during an oddball paradigm. Passive listening to low (500 Hz) and high (1000 Hz) pure tones served as additional control. For self- vs. other-related finger snapping sounds, analysis of ERPs revealed significant differences in the time windows of the N2a/MMN and P3. An subsequent source localization analysis with standardized low-resolution brain electromagnetic tomography (sLORETA) revealed increased cortical activation in distinct motor areas such as the supplementary motor area (SMA) in the N2a/mismatch negativity (MMN) as well as the P3 time window during processing of self- and other-related finger snapping sounds. In contrast, brain regions associated with self-related processing [e.g., right anterior/posterior cingulate cortex (ACC/PPC)] as well as the right inferior parietal lobule (IPL) showed increased activation particularly during processing of self- vs. other-related finger snapping sounds in the time windows of the N2a/MMN (ACC/PCC) or the P3 (IPL). None of these brain regions showed enhanced activation while listening passively to low (500 Hz) and high (1000 Hz) pure tones. Taken together, the current results indicate (1) a specific role of motor regions such as SMA during auditory processing of movement-related information, regardless of whether this information is self- or other-related, (2) activation of neural sources such as the ACC/PCC and the IPL during implicit processing of self-related movement stimuli, and (3

  11. Using Time-on-Task Measurements to Understand Student Performance in a Physics Class: A Four-Year Study

    ERIC Educational Resources Information Center

    Stewart, John; Stewart, Gay; Taylor, Jennifer

    2012-01-01

    Student use of out-of-class time was measured for four years in the introductory second-semester calculus-based physics course at the University of Arkansas. Two versions of the course were presented during the time of the measurement. In both versions, the total out-of-class time a student invested in the course explained less than 1% of the…

  12. Task-Based and Questionnaire Measures of Inhibitory Control Are Differentially Affected by Acute Food Restriction and by Motivationally Salient Food Stimuli in Healthy Adults.

    PubMed

    Bartholdy, Savani; Cheng, Jiumu; Schmidt, Ulrike; Campbell, Iain C; O'Daly, Owen G

    2016-01-01

    Adaptive eating behaviors are dependent on an interaction between motivational states (e.g., hunger) and the ability to control one's own behavior (inhibitory control). Indeed, behavioral paradigms are emerging that seek to train inhibitory control to improve eating behavior. However, inhibitory control is a multifaceted concept, and it is not yet clear how different types (e.g., reactive motor inhibition, proactive motor inhibition, reward-related inhibition) are affected by hunger. Such knowledge will provide insight into the contexts in which behavioral training paradigms would be most effective. The present study explored the impact of promoting a "need" state (hunger) together with motivationally salient distracting stimuli (food/non-food images) on inhibitory control in 46 healthy adults. Participants attended two study sessions, once after eating breakfast as usual and once after acute food restriction on the morning of the session. In each session, participants completed questionnaires on hunger, mood and inhibitory control, and undertook task-based measures of inhibitory control, and had physiological measurements (height, weight, and blood glucose) obtained by a researcher. Acute food restriction influenced task-based assessments but not questionnaire measures of inhibitory control, suggesting that hunger affects observable behavioral control but not self-reported inhibitory control. After acute food restriction, participants showed greater temporal discounting (devaluation of future rewards), and subjective hunger and these were inversely correlated with stop accuracy on the stop signal task. Finally, participants generally responded faster when food-related distractor images were presented, compared to non-food images, independent of state. This suggests that although food stimuli motivate approach behavior, stimulus relevance does not impact inhibitory control in healthy individuals, nor interact with motivational state. These findings may provide some

  13. Task-Based and Questionnaire Measures of Inhibitory Control Are Differentially Affected by Acute Food Restriction and by Motivationally Salient Food Stimuli in Healthy Adults

    PubMed Central

    Bartholdy, Savani; Cheng, Jiumu; Schmidt, Ulrike; Campbell, Iain C.; O'Daly, Owen G.

    2016-01-01

    Adaptive eating behaviors are dependent on an interaction between motivational states (e.g., hunger) and the ability to control one's own behavior (inhibitory control). Indeed, behavioral paradigms are emerging that seek to train inhibitory control to improve eating behavior. However, inhibitory control is a multifaceted concept, and it is not yet clear how different types (e.g., reactive motor inhibition, proactive motor inhibition, reward-related inhibition) are affected by hunger. Such knowledge will provide insight into the contexts in which behavioral training paradigms would be most effective. The present study explored the impact of promoting a “need” state (hunger) together with motivationally salient distracting stimuli (food/non-food images) on inhibitory control in 46 healthy adults. Participants attended two study sessions, once after eating breakfast as usual and once after acute food restriction on the morning of the session. In each session, participants completed questionnaires on hunger, mood and inhibitory control, and undertook task-based measures of inhibitory control, and had physiological measurements (height, weight, and blood glucose) obtained by a researcher. Acute food restriction influenced task-based assessments but not questionnaire measures of inhibitory control, suggesting that hunger affects observable behavioral control but not self-reported inhibitory control. After acute food restriction, participants showed greater temporal discounting (devaluation of future rewards), and subjective hunger and these were inversely correlated with stop accuracy on the stop signal task. Finally, participants generally responded faster when food-related distractor images were presented, compared to non-food images, independent of state. This suggests that although food stimuli motivate approach behavior, stimulus relevance does not impact inhibitory control in healthy individuals, nor interact with motivational state. These findings may provide

  14. Task-Based and Questionnaire Measures of Inhibitory Control Are Differentially Affected by Acute Food Restriction and by Motivationally Salient Food Stimuli in Healthy Adults

    PubMed Central

    Bartholdy, Savani; Cheng, Jiumu; Schmidt, Ulrike; Campbell, Iain C.; O'Daly, Owen G.

    2016-01-01

    Adaptive eating behaviors are dependent on an interaction between motivational states (e.g., hunger) and the ability to control one's own behavior (inhibitory control). Indeed, behavioral paradigms are emerging that seek to train inhibitory control to improve eating behavior. However, inhibitory control is a multifaceted concept, and it is not yet clear how different types (e.g., reactive motor inhibition, proactive motor inhibition, reward-related inhibition) are affected by hunger. Such knowledge will provide insight into the contexts in which behavioral training paradigms would be most effective. The present study explored the impact of promoting a “need” state (hunger) together with motivationally salient distracting stimuli (food/non-food images) on inhibitory control in 46 healthy adults. Participants attended two study sessions, once after eating breakfast as usual and once after acute food restriction on the morning of the session. In each session, participants completed questionnaires on hunger, mood and inhibitory control, and undertook task-based measures of inhibitory control, and had physiological measurements (height, weight, and blood glucose) obtained by a researcher. Acute food restriction influenced task-based assessments but not questionnaire measures of inhibitory control, suggesting that hunger affects observable behavioral control but not self-reported inhibitory control. After acute food restriction, participants showed greater temporal discounting (devaluation of future rewards), and subjective hunger and these were inversely correlated with stop accuracy on the stop signal task. Finally, participants generally responded faster when food-related distractor images were presented, compared to non-food images, independent of state. This suggests that although food stimuli motivate approach behavior, stimulus relevance does not impact inhibitory control in healthy individuals, nor interact with motivational state. These findings may provide

  15. Task-Based and Questionnaire Measures of Inhibitory Control Are Differentially Affected by Acute Food Restriction and by Motivationally Salient Food Stimuli in Healthy Adults.

    PubMed

    Bartholdy, Savani; Cheng, Jiumu; Schmidt, Ulrike; Campbell, Iain C; O'Daly, Owen G

    2016-01-01

    Adaptive eating behaviors are dependent on an interaction between motivational states (e.g., hunger) and the ability to control one's own behavior (inhibitory control). Indeed, behavioral paradigms are emerging that seek to train inhibitory control to improve eating behavior. However, inhibitory control is a multifaceted concept, and it is not yet clear how different types (e.g., reactive motor inhibition, proactive motor inhibition, reward-related inhibition) are affected by hunger. Such knowledge will provide insight into the contexts in which behavioral training paradigms would be most effective. The present study explored the impact of promoting a "need" state (hunger) together with motivationally salient distracting stimuli (food/non-food images) on inhibitory control in 46 healthy adults. Participants attended two study sessions, once after eating breakfast as usual and once after acute food restriction on the morning of the session. In each session, participants completed questionnaires on hunger, mood and inhibitory control, and undertook task-based measures of inhibitory control, and had physiological measurements (height, weight, and blood glucose) obtained by a researcher. Acute food restriction influenced task-based assessments but not questionnaire measures of inhibitory control, suggesting that hunger affects observable behavioral control but not self-reported inhibitory control. After acute food restriction, participants showed greater temporal discounting (devaluation of future rewards), and subjective hunger and these were inversely correlated with stop accuracy on the stop signal task. Finally, participants generally responded faster when food-related distractor images were presented, compared to non-food images, independent of state. This suggests that although food stimuli motivate approach behavior, stimulus relevance does not impact inhibitory control in healthy individuals, nor interact with motivational state. These findings may provide some

  16. Methods development for measuring and classifying flammability/combustibility of refrigerants. Interim report, Task 1 -- Annotated bibliography and summary

    SciTech Connect

    Heinonen, E.W.; Tapscott, R.E.

    1994-06-01

    For Task 1 of the flammable refrigerant methods development contract, NMERI performed a literature search to identify references on the flammability of refrigerants. A database to store a bibliographic record of the literature search was then developed. This database is contained in the Microsoft Access{reg_sign} relational database management system for Windows{trademark}. Searches for applicable sources were made on-line using the STN{reg_sign} scientific and technical network; off-line using the National Technical Information Service (NTIS) database; WorldCat CD-rom database; the University of New Mexico library search; the Air-Conditioning and Refrigeration institute (ARI) Refrigerant Database; and personal contacts. Three specific areas were searched: refrigerant properties, flammability test methods, and ignition technology. Many of the articles retrieved fall into multiple categories. Ignition technology was included as a separate category because of the importance of the ignition process to flammability and the vast amount of information available on ignition of gaseous fuels, especially hydrocarbons. Over 90 separate references have been entered into the database. Two separate report formats have been developed to display the results of the literature search. Appendix B is the short report format--without abstract, while Appendix C is the long format--with abstract.

  17. The use of EEG to measure cerebral changes during computer-based motion-sickness-inducing tasks

    NASA Astrophysics Data System (ADS)

    Strychacz, Christopher; Viirre, Erik; Wing, Shawn

    2005-05-01

    Motion sickness (MS) is a stressor commonly attributed with causing serious navigational and performance errors. The distinct nature of MS suggests this state may have distinct neural markers distinguishable from other states known to affect performance (e.g., stress, fatigue, sleep deprivation, high workload). This pilot study used new high-resolution electro-encephalograph (EEG) technologies to identify distinct neuronal activation changes that occur during MS. Brain EEG activity was monitored while subjects performed a ball-tracking task and viewed stimuli on a projection screen intended to induce motion sickness/spatial disorientation. Results show the presence of EEG spectral changes in all subjects who developed motion sickness when compared to baseline levels. These changes included: 1) low frequency (1 to 10 Hz) changes that may reflect oculomotor movements rather than intra-cerebral sources; 2) increased spectral power across all frequencies (attributable to increased scalp conductivity related to sweating), 3) local increases of power spectra in the 20-50 Hz range (likely attributable to external muscles on the skull) and; 4) a central posterior (occipital) independent component that shows suppression of a 20 Hz peak in the MS condition when compared to baseline. Further research is necessary to refine neural markers, characterize their origin and physiology, to distinguish between motion sickness and other states and to enable markers to be used for operator state monitoring and the designing of interventions for motion sickness.

  18. JT9D engine diagnostics. Task 2: Feasibility study of measuring in-service flight loads. [747 aircraft performance

    NASA Technical Reports Server (NTRS)

    Kafka, P. G.; Skibo, M. A.; White, J. L.

    1977-01-01

    The feasibility of measuring JT9D propulsion system flight inertia loads on a 747 airplane is studied. Flight loads background is discussed including the current status of 747/JT9D loads knowledge. An instrumentation and test plan is formulated for an airline-owned in-service airplane and the Boeing-owned RA001 test airplane. Technical and cost comparisons are made between these two options. An overall technical feasibility evaluation is made and a cost summary presented. Conclusions and recommendations are presented in regard to using existing inertia loads data versus conducting a flight test to measure inertia loads.

  19. Measuring the cognitive resources consumed per second for real-time lie-production and recollection: a dual-tasking paradigm.

    PubMed

    Hu, Chao; Huang, Kun; Hu, Xiaoqing; Liu, Yanshuo; Yuan, Fang; Wang, Qiandong; Fu, Genyue

    2015-01-01

    This research report presents a novel method of dual-tasking lie-detection. Novel software "Follow Me" was invented for a concurrent eye-hand coordination task during truth-telling/lying. Undergraduate participants were instructed to tell truths on questions about undergraduate school whereas they were instructed to tell lies on interview questions about graduate school, pretending they were graduate students. Throughout the experiment, they operated the "Follow Me" software: moving the mouse pointer to follow a randomly-moving dot on a computer screen. The distance between the mouse pointer tip and the dot center was measured by the software every 50 ms. Frequency of distance fluctuation was analyzed as the index of cognitive effort consumed per second (i.e., "degree of cognitive effort"). The results revealed that the dominant frequency of distance fluctuation was significantly lower during encoding than during retrieving responses; and lower during lying than truth-telling. Thus, dominant frequency of distance fluctuation may be an effective index of cognitive effort. Moreover, both encoding and retrieving bald-faced lies were more cognitively effortful than truth-telling. This novel definition and measurement of degree of cognitive effort may contribute to the research field of deception as well as to many other fields in social cognition.

  20. Measuring the cognitive resources consumed per second for real-time lie-production and recollection: a dual-tasking paradigm.

    PubMed

    Hu, Chao; Huang, Kun; Hu, Xiaoqing; Liu, Yanshuo; Yuan, Fang; Wang, Qiandong; Fu, Genyue

    2015-01-01

    This research report presents a novel method of dual-tasking lie-detection. Novel software "Follow Me" was invented for a concurrent eye-hand coordination task during truth-telling/lying. Undergraduate participants were instructed to tell truths on questions about undergraduate school whereas they were instructed to tell lies on interview questions about graduate school, pretending they were graduate students. Throughout the experiment, they operated the "Follow Me" software: moving the mouse pointer to follow a randomly-moving dot on a computer screen. The distance between the mouse pointer tip and the dot center was measured by the software every 50 ms. Frequency of distance fluctuation was analyzed as the index of cognitive effort consumed per second (i.e., "degree of cognitive effort"). The results revealed that the dominant frequency of distance fluctuation was significantly lower during encoding than during retrieving responses; and lower during lying than truth-telling. Thus, dominant frequency of distance fluctuation may be an effective index of cognitive effort. Moreover, both encoding and retrieving bald-faced lies were more cognitively effortful than truth-telling. This novel definition and measurement of degree of cognitive effort may contribute to the research field of deception as well as to many other fields in social cognition. PMID:25999903

  1. Measuring the cognitive resources consumed per second for real-time lie-production and recollection: a dual-tasking paradigm

    PubMed Central

    Hu, Chao; Huang, Kun; Hu, Xiaoqing; Liu, Yanshuo; Yuan, Fang; Wang, Qiandong; Fu, Genyue

    2015-01-01

    This research report presents a novel method of dual-tasking lie-detection. Novel software “Follow Me” was invented for a concurrent eye-hand coordination task during truth-telling/lying. Undergraduate participants were instructed to tell truths on questions about undergraduate school whereas they were instructed to tell lies on interview questions about graduate school, pretending they were graduate students. Throughout the experiment, they operated the “Follow Me” software: moving the mouse pointer to follow a randomly-moving dot on a computer screen. The distance between the mouse pointer tip and the dot center was measured by the software every 50 ms. Frequency of distance fluctuation was analyzed as the index of cognitive effort consumed per second (i.e., “degree of cognitive effort”). The results revealed that the dominant frequency of distance fluctuation was significantly lower during encoding than during retrieving responses; and lower during lying than truth-telling. Thus, dominant frequency of distance fluctuation may be an effective index of cognitive effort. Moreover, both encoding and retrieving bald-faced lies were more cognitively effortful than truth-telling. This novel definition and measurement of degree of cognitive effort may contribute to the research field of deception as well as to many other fields in social cognition. PMID:25999903

  2. Methods development for measuring and classifying flammability/combustibility of refrigerants. Interim report, task 2 - test plan

    SciTech Connect

    Heinonen, E.W.; Tapscott, R.E.

    1994-07-01

    Regulations on alternative refrigerants and concerns for the environment are forcing the refrigeration industry to consider the use of potentially flammable fluids to replace CFC fluids currently in use. The objectives of this program are to establish the conditions under which refrigerants and refrigerant blends exhibit flammability and to develop appropriate methods to measure flammability.

  3. Ability to Identify, Explain and Solve Problems in Everyday Tasks: Preliminary Validation of a Direct Video Measure of Practical Intelligence

    ERIC Educational Resources Information Center

    Yalon-Chamovitz, Shira; Greenspan, Stephen

    2005-01-01

    Recent developments in the definitional literature on mental retardation emphasize the need to ground the concept of adaptive behavior in an expanded model of intelligence, which includes practical and social intelligence. Development of a direct measure of practical intelligence might increase the likelihood that an assessment of this domain…

  4. Exploring the Mathematical Knowledge for Teaching Geometry and Measurement through the Design and Use of Rich Assessment Tasks

    ERIC Educational Resources Information Center

    Steele, Michael D.

    2013-01-01

    While recent national and international assessments have shown mathematical progress being made by US students, little to no gains are evident in the areas of geometry and measurement. These reports also suggest that practicing teachers have traditionally had few opportunities to engage in content learning around topics in geometry and…

  5. Intra-Rater Reliability and Minimal Detectable Change of Vertical Ground Reaction Force Measurement during Gait and Half-Squat Tasks on Healthy Male Adults

    PubMed Central

    Fairus, Fariza Zainudin; Joseph, Leonard Henry; Omar, Baharudin; Ahmad, Johan; Sulaiman, Riza

    2016-01-01

    Background The understanding of vertical ground reaction force (VGRF) during walking and half-squatting is necessary and commonly utilised during the rehabilitation period. The purpose of this study was to establish measurement reproducibility of VGRF that reports the minimal detectable changes (MDC) during walking and half-squatting activity among healthy male adults. Methods 14 male adults of average age, 24.88 (5.24) years old, were enlisted in this study. The VGRF was assessed using the force plates which were embedded into a customised walking platform. Participants were required to carry out three trials of gait and half-squat. Each participant completed the two measurements within a day, approximately four hours apart. Results Measurements of VGRF between sessions presented an excellent VGRF data for walking (ICC Left = 0.88, ICC Right = 0.89). High reliability of VGRF was also noted during the half-squat activity (ICC Left = 0.95, ICC Right = 0.90). The standard errors of measurement (SEM) of VGRF during the walking and half-squat activity are less than 8.35 Nm/kg and 4.67 Nm/kg for the gait and half-squat task respectively. Conclusion The equipment set-up and measurement procedure used to quantify VGRF during walking and half-squatting among healthy males displayed excellent reliability. Researcher should consider using this method to measure the VGRF during functional performance assessment. PMID:27547111

  6. A Full Mission Simulator Study of Aircrew Performances: the Measurement of Crew Coordination and Decisionmaking Factors and Their Relationships to Flight Task Performances

    NASA Technical Reports Server (NTRS)

    Murphy, M. R.; Randle, R. J.; Tanner, T. A.; Frankel, R. M.; Goguen, J. A.; Linde, C.

    1984-01-01

    Sixteen three man crews flew a full mission scenario in an airline flight simulator. A high level of verbal interaction during instances of critical decision making was located. Each crew flew the scenario only once, without prior knowledge of the scenario problem. Following a simulator run and in accord with formal instructions, each of the three crew members independently viewed and commented on a videotape of their performance. Two check pilot observers rated pilot performance across all crews and, following each run, also commented on the video tape of the crew's performance. A linguistic analysis of voice transcript is made to provide assessment of crew coordination and decision making qualities. Measures of crew coordination and decision making factors are correlated with flight task performance measures.

  7. Generic cognitive adaptations to task interference in task switching.

    PubMed

    Poljac, Edita; Bekkering, Harold

    2009-11-01

    The present study investigated how the activation of previous tasks interferes with the execution of future tasks as a result of temporal manipulations. Color and shape matching tasks were organized in runs of two trials each. The tasks were specified by a cue presented before a task run, cueing only the first trials of each run. Response times (RTs) and error rates were measured for task switching and task repetition conditions. Task interference was varied as a function of response-cue interval (RCI of 300 and 900ms), that is, the interval between the task runs. Keeping the response-stimulus interval within the task runs constant at 300ms allowed the disentangling of the direct effects of RCI manipulation on performance (first trials) from the general effects on performance (both trials in the run). The data showed similar performance improvement due to RCI increase on both trials in the task run. Furthermore, increasing RCI improved both switch and repetition performance to a similar extent. Together, our findings provide further evidence for accounts stressing generic effects of proactive task interference in task switching.

  8. [The preanalytical stage of under measuring of concentration of catalytic activity of enzymes: the characteristics and tasks of standardization].

    PubMed

    Lukicheva, T I; Men'shikov, V V

    2012-06-01

    The article explains the importance of standardization, the development and maintenance of rules and recommendations regulating the conditions and order of implementation of particular parts of preanalytical stage. The order of these conditions is noted including the rules stated and published in such normative documents as national standards GOST R 15 189-2009, GOST R 53079.4-2008, GOST R ISO 6710-209 and in the recommendations of foreign National societies ofclini-cal chemistry and laboratory medicine. These requirements concern all the analytes, enzymes included. The cited data have a practical significance for acquisition of reliable results in everyday functioning of laboratories. Enough to mention data concerning the anticoagulants influence on catalytic concentration of enzymes, the most often measured concentrations of alpha-amylase, lipase, amynotransferase, alkaline and acid phosphatase, creatine kinase, lactate dehydrogenase, choline esterase, hemolysis impact, the increased concentration of bilirubin and hyperlipemia in samples and significance of measurement of indices of serum and plasma as well. The possible mechanisms of impact of these interferents on the results of measurement of catalytic concentration of enzymes are discussed.

  9. Results of the Round Robin on opening-load measurement conducted by ASTM Task Group E24.04.04 on Crack Closure Measurement and Analysis

    NASA Technical Reports Server (NTRS)

    Phillips, Edward P.

    1989-01-01

    An experimental Round Robin on the measurement of the opening load in fatigue crack growth tests was conducted on Crack Closure Measurement and Analysis. The Round Robin evaluated the current level of consistency of opening load measurements among laboratories and to identify causes for observed inconsistency. Eleven laboratories participated in the testing of compact and middle-crack specimens. Opening-load measurements were made for crack growth at two stress-intensity factor levels, three crack lengths, and following an overload. All opening-load measurements were based on the analysis of specimen compliance data. When all of the results reported (from all participants, all measurement methods, and all data analysis methods) for a given test condition were pooled, the range of opening loads was very large--typically spanning the lower half of the fatigue loading cycle. Part of the large scatter in the reported opening-load results was ascribed to consistent differences in results produced by the various methods used to measure specimen compliance and to evaluate the opening load from the compliance data. Another significant portion of the scatter was ascribed to lab-to-lab differences in producing the compliance data when using nominally the same method of measurement.

  10. High-Alcohol Preferring Mice Are More Impulsive Than Low-Alcohol Preferring Mice as Measured in the Delay Discounting Task

    PubMed Central

    Oberlin, B. G.; Grahame, N. J.

    2010-01-01

    Background Repeated studies have shown that high impulsivity, when defined as the tendency to choose small immediate rewards over larger delayed rewards, is more prevalent in drug addicts and alcoholics when compared with nonaddicts. Assessing whether impulsivity precedes and potentially causes addiction disorders is difficult in humans because they all share a history of drug use. In this study, we address this question by testing alcohol-naïve mice from lines showing heritable differences in alcohol intake. Methods Replicated selected lines of outbred high-alcohol preferring (HAP) mice were compared to a low-alcohol preferring (LAP) line as well as the low-drinking progenitor line (HS/Ibg) on an adjusting amount delay discounting (DD) task. The DD task employs 2 levers to present subjects with a choice between a small, immediate and a large, delayed saccharin reward. By adjusting the quantity of the immediate reward up and down based on choice behavior, the task allows an estimate of how the subjective value of the delayed reinforcer decreases as delays increase. Latency to respond was also measured for each trial. Results Both HAP2 and HAP1 lines of mice were more impulsive than the LAP2 and HS/Ibg lines, respectively. Hyperbolic curve-fitting confirmed steeper discounting in the high-alcohol drinking lines. In addition, the high-alcohol drinking lines demonstrated greater within-session increases in reaction times relative to the low-alcohol drinking lines. No other differences (consumption of saccharin, total trials completed) consistently mapped onto genetic differences in alcohol drinking. Conclusions Alcohol-naïve outbred mice selected for high-alcohol drinking were more impulsive with saccharin reinforcers than low-alcohol drinkers. These data are consistent with results seen using inbred strain descendents of high-alcohol drinking and low-alcohol drinking rat lines, and suggest that impulsivity is a heritable difference that precedes alcoholism. PMID

  11. Eye fixation related potentials in a target search task.

    PubMed

    Healy, Graham; Smeaton, Alan F

    2011-01-01

    Typically BCI (Brain Computer Interfaces) are found in rehabilitative or restorative applications, often allowing users a medium of communication that is otherwise unavailable through conventional means. Recently, however, there is growing interest in using BCI to assist users in searching for images. A class of neural signals often leveraged in common BCI paradigms are ERPs (Event Related Potentials), which are present in the EEG (Electroencephalograph) signals from users in response to various sensory events. One such ERP is the P300, and is typically elicited in an oddball experiment where a subject's attention is orientated towards a deviant stimulus among a stream of presented images. It has been shown that these types of neural responses can be used to drive an image search or labeling task, where we can rank images by examining the presence of such ERP signals in response to the display of images. To date, systems like these have been demonstrated when presenting sequences of images containing targets at up to 10 Hz, however, the target images in these tasks do not necessitate any kind of eye movement for their detection because the targets in the images are quite salient. In this paper we analyse the presence of discriminating EEG signals when they are offset to the time of eye fixations in a visual search task where detection of target images does require eye fixations.

  12. Geophysical and transport properties of reservoir rocks. Final report for task 4: Measurements and analysis of seismic properties

    SciTech Connect

    Cook, N.G.W.

    1993-05-01

    The principal objective of research on the seismic properties of reservoir rocks is to develop a basic understanding of the effects of rock microstructure and its contained pore fluids on seismic velocities and attenuation. Ultimately, this knowledge would be used to extract reservoir properties information such as the porosity, permeability, clay content, fluid saturation, and fluid type from borehole, cross-borehole, and surface seismic measurements to improve the planning and control of oil and gas recovery. This thesis presents laboratory ultrasonic measurements for three granular materials and attempts to relate the microstructural properties and the properties of the pore fluids to P- and S-wave velocities and attenuation. These experimental results show that artificial porous materials with sintered grains and a sandstone with partially cemented grains exhibit complexities in P- and S-wave attenuation that cannot be adequately explained by existing micromechanical theories. It is likely that some of the complexity observed in the seismic attenuation is controlled by details of the rock microstructure, such as the grain contact area and grain shape, and by the arrangement of the grain packing. To examine these effects, a numerical method was developed for analyzing wave propagation in a grain packing. The method is based on a dynamic boundary integral equation and incorporates generalized stiffness boundary conditions between individual grains to account for viscous losses and grain contact scattering.

  13. Real-time estimate of body kinematics during a planar squat task using a single inertial measurement unit.

    PubMed

    Bonnet, Vincent; Mazzà, Claudia; Fraisse, Philippe; Cappozzo, Aurelio

    2013-07-01

    This study aimed at the real-time estimation of the lower-limb joint and torso kinematics during a squat exercise, performed in the sagittal plane, using a single inertial measurement unit placed on the lower back. The human body was modeled with a 3-DOF planar chain. The planar IMU orientation and vertical displacement were estimated using one angular velocity and two acceleration components and a weighted Fourier linear combiner. The ankle, knee, and hip joint angles were thereafter obtained through a novel inverse kinematic module based on the use of a Jacobian pseudoinverse matrix and null-space decoupling. The aforementioned algorithms were validated on a humanoid robot for which the mechanical model used and the measured joint angles virtually exhibited no inaccuracies. Joint angles were estimated with a maximal error of 1.5°. The performance of the proposed analytical and experimental methodology was also assessed by conducting an experiment on human volunteers and by comparing the relevant results with those obtained through the more conventional photogrammetric approach. The joint angles provided by the two methods displayed differences equal to 3±1°. These results, associated with the real-time capability of the method, open the door to future field applications in both rehabilitation and sport. PMID:23392337

  14. Behavioral measures of risk tasking, sensation seeking and sensitivity to reward may reflect different motivations for spicy food liking and consumption.

    PubMed

    Byrnes, Nadia K; Hayes, John E

    2016-08-01

    Based on work a quarter century ago, it is widely accepted personality traits like sensation seeking are related to the enjoyment and intake of spicy foods; however, data supporting this belief is actually quite limited. Recently, we reported strong to moderate correlations between remembered spicy food liking and two personality traits measured with validated questionnaires. Here, participants consumed capsaicin-containing strawberry jelly to generate acute estimates of spicy food liking. Additionally, we used a laboratory-based behavioral measure of risk taking (the mobile Balloon Analogue Risk Task; mBART) to complement a range of validated self-report measures of risk-related personality traits. Present data confirm Sensation Seeking correlates with overall spicy meal liking and liking of the burn of a spicy meal, and extends prior findings by showing novel correlations with the liking of sampled stimuli. Other personality measures, including Sensitivity to Punishment (SP), Sensitivity to Reward (SR), and the Impulsivity and Risk Taking subscales of the DSM5 Personality Inventory (PID-5) did not show significant relationships with liking of spicy foods, either sampled or remembered. Our behavioral risk taking measure, the mBART, also failed to show a relationship with remembered or sampled liking. However, significant relationships were observed between reported intake of spicy foods and Sensitivity to Reward, and the Risk Taking subscale of the PID-5 (PID5-RT). Based on the observed patterns among various personality measures, and spicy food liking and intake, we propose that personality measures may exert their influence on intake of spicy food via different mechanisms. We also speculate that Sensation Seeking may reflect motivations for consuming spicy foods that are more intrinsic, while the motivations for eating spicy foods measured by SR and PID5-RT may be more extrinsic. PMID:27137410

  15. Introduction to meteorological measurements and data handling for solar energy applications. Task IV-Development of an insolation handbook and instrument package

    SciTech Connect

    1980-10-01

    Recognizing a need for a coordinated approach to resolve energy problems, certain members of the Organization for Economic Cooperation and Development (OECD) met in September 1974 and agreed to develop an International Energy Program. The International Energy Agency (IEA) was established within the OECD to administer, monitor and execute this International Energy Program. In July 1975, Solar Heating and Cooling was selected as one of the sixteen technology fields for multilateral cooperation. Five project areas, called tasks, were identified for cooperative activities within the IEA Program to Develop and Test Solar Heating and Cooling Systems. The objective of one task was to obtain improved basic resource information for the design and operation of solar heating and cooling systems through a better understanding of the required insolation (solar radiation) and related weather data, and through improved techniques for measurement and evaluation of such data. At the February 1976 initial experts meeting in Norrkoeping, Sweden, the participants developed the objective statement into two subtasks. (1) an insolation handbook; and (2) a portable meteorological instrument package. This handbook is the product of the first subtask. The objective of this handbook is to provide a basis for a dialogue between solar scientists and meteorologists. Introducing the solar scientist to solar radiation and related meteorological data enables him to better express his scientific and engineering needs to the meteorologist; and introducing the meteorologist to the special solar radiation and meteorological data applications of the solar scientist enables him to better meet the needs of the solar energy community.

  16. ACCF/AHA methodology for the development of quality measures for cardiovascular technology: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Performance Measures.

    PubMed

    Bonow, Robert O; Douglas, Pamela S; Buxton, Alfred E; Cohen, David J; Curtis, Jeptha P; Delong, Elizabeth; Drozda, Joseph P; Ferguson, T Bruce; Heidenreich, Paul A; Hendel, Robert C; Masoudi, Frederick A; Peterson, Eric D; Taylor, Allen J

    2011-09-27

    Consistent with the growing national focus on healthcare quality, the American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA) have taken a leadership role over the past decade in developing measures of the quality of cardiovascular care by convening a joint ACCF/AHA Task Force on Performance Measures. The Task Force is charged with identifying the clinical topics appropriate for the development of performance measures and with assembling writing committees composed of clinical and methodological experts in collaboration with appropriate subspecialty societies. The Task Force has also created methodology documents that offer guidance in the development of process, outcome, composite, and efficiency measures. Cardiovascular performance measures using existing ACCF/AHA methodology are based on Class I or Class III guidelines recommendations, usually with Level A evidence. These performance measures, based on evidence-based ACCF/AHA guidelines, remain the most rigorous quality measures for both internal quality improvement and public reporting. However, many of the tools for diagnosis and treatment of cardiovascular disease involve advanced technologies, such as cardiac imaging, for which there are often no underlying guideline documents. Because these technologies affect the quality of cardiovascular care and also have the potential to contribute to cardiovascular health expenditures, there is a need for more critical assessment of the use of technology, including the development of quality and performance measures in areas in which guideline recommendations are absent. The evaluation of quality in the use of cardiovascular technologies requires consideration of multiple parameters that differ from other healthcare processes. The present document describes methodology for development of 2 new classes of quality measures in these situations, appropriate use measures and structure/safety measures. Appropriate use measures are based on

  17. Investigating Perfect Timesharing: The Relationship between IM-Compatible Tasks and Dual-Task Performance

    ERIC Educational Resources Information Center

    Halvorson, Kimberly M.; Ebner, Herschel; Hazeltine, Eliot

    2013-01-01

    Why are dual-task costs reduced with ideomotor (IM) compatible tasks (Greenwald & Shulman, 1973; Lien, Proctor & Allen, 2002)? In the present experiments, we first examine three different measures of single-task performance (pure single-task blocks, mixed blocks, and long stimulus onset asynchrony [SOA] trials in dual-task blocks) and two measures…

  18. PRESCHOOL CHILDREN'S WILLINGNESS TO TRY DIFFICULT TASKS.

    ERIC Educational Resources Information Center

    STARKWEATHER, ELIZABETH K.

    INSTRUMENTS WERE ADMINISTERED TO PRESCHOOL CHILDREN TO MEASURE THEIR PERFORMANCE ON VARIOUS TASKS. THE INSTRUMENTS WERE (1) A BUTTONING TASK FOR FINE MOTOR COORDINATION, (2) A PUZZLE TASK FOR VISUAL DISCRIMINATION, AND (3) A TARGET GAME FOR GROSS MOTOR COORDINATION. EACH INSTRUMENT CONSISTED OF FIVE TASKS GRADED IN DIFFICULTY, ADJUSTED TO THE…

  19. Reliable jitter and shimmer measurements in voice clinics: the relevance of vowel, gender, vocal intensity, and fundamental frequency effects in a typical clinical task.

    PubMed

    Brockmann, Meike; Drinnan, Michael J; Storck, Claudio; Carding, Paul N

    2011-01-01

    The aims of this study were to examine vowel and gender effects on jitter and shimmer in a typical clinical voice task while correcting for the confounding effects of voice sound pressure level (SPL) and fundamental frequency (F(0)). Furthermore the relative effect sizes of vowel, gender, voice SPL, and F(0) were assessed, and recommendations for clinical measurements were derived. With this cross-sectional single cohort study, 57 healthy adults (28 women, 29 men) aged 20-40 years were investigated. Three phonations of /a/, /o/, and /i/ at "normal" voice loudness were analyzed using Praat (software). The effects of vowel, gender, voice SPL, and F(0) on jitter and shimmer were assessed using descriptive and inferential (analysis of covariance) statistics. The effect sizes were determined with the eta-squared statistic. Vowels, gender, voice SPL, and F(0), each had significant effects either on jitter or on shimmer, or both. Voice SPL was the most important factor, whereas vowel, gender, and F(0) effects were comparatively small. Because men had systematically higher voice SPL, the gender effects on jitter and shimmer were smaller when correcting for SPL and F(0). Surprisingly, in clinical assessments, voice SPL has the single biggest impact on jitter and shimmer. Vowel and gender effects were clinically important, whereas fundamental frequency had a relatively small influence. Phonations at a predefined voice SPL (80 dB minimum) and vowel (/a/) would enhance measurement reliability. Furthermore, gender-specific thresholds applying these guidelines should be established. However, the efficiency of these measures should be verified and tested with patients.

  20. Creativity, Overinclusion, and Everyday Tasks

    ERIC Educational Resources Information Center

    Ottemiller, Dylan D.; Elliott, Colette Seter; Giovannetti, Tania

    2014-01-01

    This study examined relations between creative thinking and performance on routine, everyday tasks. Results were considered in light of past research on the putative relation between creativity and schizophrenia/psychotic thinking. Thirty healthy undergraduates completed the Alternative Uses Task, a measure of divergent thinking, and the 2 × 3…

  1. Measurement and Analysis of Olfactory Responses with the Aim of Establishing an Objective Diagnostic Method for Central Olfactory Disorders

    NASA Astrophysics Data System (ADS)

    Uno, Tominori; Wang, Li-Qun; Miwakeichi, Fumikazu; Tonoike, Mitsuo; Kaneda, Teruo

    In order to establish a new diagnostic method for central olfactory disorders and to identify objective indicators, we measured and analyzed brain activities in the parahippocampal gyrus and uncus, region of responsibility for central olfactory disorders. The relationship between olfactory stimulation and brain response at region of responsibility can be examined in terms of fitted responses (FR). FR in these regions may be individual indicators of changes in brain olfactory responses. In the present study, in order to non-invasively and objectively measure olfactory responses, an odor oddball task was conducted on four healthy volunteers using functional magnetic resonance imaging (fMRI) and a odorant stimulator with blast-method. The results showed favorable FR and activation in the parahippocampal gyrus or uncus in all subjects. In some subjects, both the parahippocampal gyrus and uncus were activated. Furthermore, activation was also confirmed in the cingulate gyrus, middle frontal gyrus, precentral gyrus, postcentral gyrus, superior temporal gyrus and insula. The hippocampus and uncus are known to be involved in the olfactory disorders associated with early-stage Alzheimer's disease and other olfactory disorders. In the future, it will be necessary to further develop the present measurement and analysis method to clarify the relationship between central olfactory disorders and brain activities and establish objective indicators that are useful for diagnosis.

  2. Altering the primacy bias--how does a prior task affect mismatch negativity?

    PubMed

    Mullens, Daniel; Woodley, Jessica; Whitson, Lisa; Provost, Alexander; Heathcote, Andrew; Winkler, István; Todd, Juanita

    2014-05-01

    The role in which two tones are first encountered in an unattended oddball sequence affects how deviance detection, reflected by mismatch negativity, treats them later when the roles reverse: a "primacy bias." We tested whether this effect is modulated by previous behavioral relevance assigned to the two tones. To this end, sequences in which the roles of the two tones alternated were preceded by a go/no-go task in which tones were presented with equal probability. Half of the participants were asked to respond to the short sounds, the other half to long sounds. Primacy bias was initially abolished but returned dependent upon the go-stimulus that the participant was assigned. Results demonstrate a long-term impact of prior learning on deviance detection, and that even when prior importance/equivalence is learned, the bias ultimately returns. Results are discussed in terms of persistent go-stimulus specific changes in responsiveness to sound.

  3. Distributed feature binding in the auditory modality: experimental evidence toward reconciliation of opposing views on the basis of mismatch negativity and behavioral measures.

    PubMed

    Chernyshev, Boris V; Bryzgalov, Dmitri V; Lazarev, Ivan E; Chernysheva, Elena G

    2016-08-01

    Current understanding of feature binding remains controversial. Studies involving mismatch negativity (MMN) measurement show a low level of binding, whereas behavioral experiments suggest a higher level. We examined the possibility that the two levels of feature binding coexist and may be shown within one experiment. The electroencephalogram was recorded while participants were engaged in an auditory two-alternative choice task, which was a combination of the oddball and the condensation tasks. Two types of deviant target stimuli were used - complex stimuli, which required feature conjunction to be identified, and simple stimuli, which differed from standard stimuli in a single feature. Two behavioral outcomes - correct responses and errors - were analyzed separately. Responses to complex stimuli were slower and less accurate than responses to simple stimuli. MMN was prominent and its amplitude was similar for both simple and complex stimuli, whereas the respective stimuli differed from standards in a single feature or two features respectively. Errors in response only to complex stimuli were associated with decreased MMN amplitude. P300 amplitude was greater for complex stimuli than for simple stimuli. Our data are compatible with the explanation that feature binding in auditory modality depends on two concurrent levels of processing. We speculate that the earlier level related to MMN generation is an essential and critical stage. Yet, a later analysis is also carried out, affecting P300 amplitude and response time. The current findings provide resolution to conflicting views on the nature of feature binding and show that feature binding is a distributed multilevel process. PMID:27306594

  4. Distributed feature binding in the auditory modality: experimental evidence toward reconciliation of opposing views on the basis of mismatch negativity and behavioral measures.

    PubMed

    Chernyshev, Boris V; Bryzgalov, Dmitri V; Lazarev, Ivan E; Chernysheva, Elena G

    2016-08-01

    Current understanding of feature binding remains controversial. Studies involving mismatch negativity (MMN) measurement show a low level of binding, whereas behavioral experiments suggest a higher level. We examined the possibility that the two levels of feature binding coexist and may be shown within one experiment. The electroencephalogram was recorded while participants were engaged in an auditory two-alternative choice task, which was a combination of the oddball and the condensation tasks. Two types of deviant target stimuli were used - complex stimuli, which required feature conjunction to be identified, and simple stimuli, which differed from standard stimuli in a single feature. Two behavioral outcomes - correct responses and errors - were analyzed separately. Responses to complex stimuli were slower and less accurate than responses to simple stimuli. MMN was prominent and its amplitude was similar for both simple and complex stimuli, whereas the respective stimuli differed from standards in a single feature or two features respectively. Errors in response only to complex stimuli were associated with decreased MMN amplitude. P300 amplitude was greater for complex stimuli than for simple stimuli. Our data are compatible with the explanation that feature binding in auditory modality depends on two concurrent levels of processing. We speculate that the earlier level related to MMN generation is an essential and critical stage. Yet, a later analysis is also carried out, affecting P300 amplitude and response time. The current findings provide resolution to conflicting views on the nature of feature binding and show that feature binding is a distributed multilevel process.

  5. Effects of the short-term learned significance of task-irrelevant sounds on involuntary attention in children and adults.

    PubMed

    Wetzel, Nicole

    2015-10-01

    The present study aimed to test effects of unexpected task-irrelevant environmental sounds, that were short-term learned to be significant, on deviance-related brain activity (event-related potentials; ERPs) and performance in children aged 9-10 years and young adults. Participants performed three conditions. In the first ignore condition an oddball paradigm was presented including two neutral deviant sounds. In the second learning condition significance was attributed to one of the two deviant sounds by defining it as target. In the third condition participants then performed a version of an oddball paradigm, embedded in a narrative, that included the neutral and the now significant but task-irrelevant deviant sound. Results revealed decreased reaction times and hit rates elicited by significant compared to neutral deviant sounds in both age groups whereas P3a, an indicator of orienting of attention and novelty evaluation, was not affected by deviant's learned significance. In contrast, post-deviant processing, reflected by hit rates and ERPs in trials following a significant deviant compared to those following a neutral deviant, was differently modulated in children and adults. Moreover, a clear P3a was observed in the attend condition in both age groups but in the ignore condition in children only. Results indicate that the short-term learned significance of task-irrelevant sounds modulates performance but not orienting and evaluation processes associated with the P3a. Importantly, results demonstrate children's increased susceptibility to task-irrelevant but significant sounds and the ongoing maturation of attention control in the late childhood.

  6. Prestimulus EEG Alpha Oscillations Modulate Task-Related fMRI BOLD Responses to Auditory Stimuli

    PubMed Central

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

    2015-01-01

    EEG alpha-band activity is generally thought to represent an inhibitory state related to decreased attention and play a role in suppression of task-irrelevant stimulus processing, but a competing hypothesis suggests an active role in processing task-relevant information – one in which phase dynamics are involved. Here we used simultaneous EEG-fMRI and a whole-brain analysis to investigate the effects of prestimulus alpha activity on the event-related BOLD response during an auditory oddball task. We separately investigated the effects of the posterior alpha rhythm’s power and phase on activity related to task-relevant stimulus processing and also investigated higher-level decision-related processing. We found stronger decision-related BOLD activity in areas late in the processing stream when subjects were in the high alpha power state prior to stimulus onset, but did not detect any effect in primary sensory regions. Our phase analysis revealed correlates in bilateral thalamus, providing support for a thalamo-cortical loop in attentional modulations and suggesting that the cortical alpha rhythm acts as a cyclic modulator of task-related responses very early in the processing stream. Our results help to reconcile the competing inhibition and active-processing hypotheses for ongoing alpha oscillations and begin to tease apart the distinct roles and mechanisms underlying their power and phase. PMID:25797833

  7. Task Prioritization in Dual-Tasking: Instructions versus Preferences.

    PubMed

    Jansen, Reinier J; van Egmond, René; de Ridder, Huib

    2016-01-01

    The role of task prioritization in performance tradeoffs during multi-tasking has received widespread attention. However, little is known on whether people have preferences regarding tasks, and if so, whether these preferences conflict with priority instructions. Three experiments were conducted with a high-speed driving game and an auditory memory task. In Experiment 1, participants did not receive priority instructions. Participants performed different sequences of single-task and dual-task conditions. Task performance was evaluated according to participants' retrospective accounts on preferences. These preferences were reformulated as priority instructions in Experiments 2 and 3. The results showed that people differ in their preferences regarding task prioritization in an experimental setting, which can be overruled by priority instructions, but only after increased dual-task exposure. Additional measures of mental effort showed that performance tradeoffs had an impact on mental effort. The interpretation of these findings was used to explore an extension of Threaded Cognition Theory with Hockey's Compensatory Control Model. PMID:27391779

  8. Task Prioritization in Dual-Tasking: Instructions versus Preferences

    PubMed Central

    Jansen, Reinier J.; van Egmond, René; de Ridder, Huib

    2016-01-01

    The role of task prioritization in performance tradeoffs during multi-tasking has received widespread attention. However, little is known on whether people have preferences regarding tasks, and if so, whether these preferences conflict with priority instructions. Three experiments were conducted with a high-speed driving game and an auditory memory task. In Experiment 1, participants did not receive priority instructions. Participants performed different sequences of single-task and dual-task conditions. Task performance was evaluated according to participants’ retrospective accounts on preferences. These preferences were reformulated as priority instructions in Experiments 2 and 3. The results showed that people differ in their preferences regarding task prioritization in an experimental setting, which can be overruled by priority instructions, but only after increased dual-task exposure. Additional measures of mental effort showed that performance tradeoffs had an impact on mental effort. The interpretation of these findings was used to explore an extension of Threaded Cognition Theory with Hockey’s Compensatory Control Model. PMID:27391779

  9. Task Prioritization in Dual-Tasking: Instructions versus Preferences.

    PubMed

    Jansen, Reinier J; van Egmond, René; de Ridder, Huib

    2016-01-01

    The role of task prioritization in performance tradeoffs during multi-tasking has received widespread attention. However, little is known on whether people have preferences regarding tasks, and if so, whether these preferences conflict with priority instructions. Three experiments were conducted with a high-speed driving game and an auditory memory task. In Experiment 1, participants did not receive priority instructions. Participants performed different sequences of single-task and dual-task conditions. Task performance was evaluated according to participants' retrospective accounts on preferences. These preferences were reformulated as priority instructions in Experiments 2 and 3. The results showed that people differ in their preferences regarding task prioritization in an experimental setting, which can be overruled by priority instructions, but only after increased dual-task exposure. Additional measures of mental effort showed that performance tradeoffs had an impact on mental effort. The interpretation of these findings was used to explore an extension of Threaded Cognition Theory with Hockey's Compensatory Control Model.

  10. Auditory evoked potentials in patients with major depressive disorder measured by Emotiv system.

    PubMed

    Wang, Dongcui; Mo, Fongming; Zhang, Yangde; Yang, Chao; Liu, Jun; Chen, Zhencheng; Zhao, Jinfeng

    2015-01-01

    In a previous study (unpublished), Emotiv headset was validated for capturing event-related potentials (ERPs) from normal subjects. In the present follow-up study, the signal quality of Emotiv headset was tested by the accuracy rate of discriminating Major Depressive Disorder (MDD) patients from the normal subjects. ERPs of 22 MDD patients and 15 normal subjects were induced by an auditory oddball task and the amplitude of N1, N2 and P3 of ERP components were specifically analyzed. The features of ERPs were statistically investigated. It is found that Emotiv headset is capable of discriminating the abnormal N1, N2 and P3 components in MDD patients. Relief-F algorithm was applied to all features for feature selection. The selected features were then input to a linear discriminant analysis (LDA) classifier with leave-one-out cross-validation to characterize the ERP features of MDD. 127 possible combinations out of the selected 7 ERP features were classified using LDA. The best classification accuracy was achieved to be 89.66%. These results suggest that MDD patients are identifiable from normal subjects by ERPs measured by Emotiv headset.

  11. Multiple paths in complex tasks

    NASA Technical Reports Server (NTRS)

    Galanter, Eugene; Wiegand, Thomas; Mark, Gloria

    1987-01-01

    The relationship between utility judgments of subtask paths and the utility of the task as a whole was examined. The convergent validation procedure is based on the assumption that measurements of the same quantity done with different methods should covary. The utility measures of the subtasks were obtained during the performance of an aircraft flight controller navigation task. Analyses helped decide among various models of subtask utility combination, whether the utility ratings of subtask paths predict the whole tasks utility rating, and indirectly, whether judgmental models need to include the equivalent of cognitive noise.

  12. Investigating perfect timesharing: the relationship between IM-compatible tasks and dual-task performance.

    PubMed

    Halvorson, Kimberly M; Ebner, Herschel; Hazeltine, Eliot

    2013-04-01

    Why are dual-task costs reduced with ideomotor (IM) compatible tasks (Greenwald & Shulman, 1973; Lien, Proctor & Allen, 2002)? In the present experiments, we first examine three different measures of single-task performance (pure single-task blocks, mixed blocks, and long stimulus onset asynchrony [SOA] trials in dual-task blocks) and two measures of dual-task performance (simultaneous stimulus presentation blocks and simultaneous stimulus presentation trials in blocks with mixed SOAs), and show that these different measures produce different estimates of the cost. Next we examine whether the near elimination of costs can be explained by assuming that one or both of the tasks bypasses capacity-limited central operations. The results indicate that both tasks must be IM-compatible to nearly eliminate the dual-task costs, suggesting that the relationship between the tasks plays a critical role in overlapping performance. PMID:22866763

  13. Decision paths in complex tasks

    NASA Technical Reports Server (NTRS)

    Galanter, Eugene

    1991-01-01

    Complex real world action and its prediction and control has escaped analysis by the classical methods of psychological research. The reason is that psychologists have no procedures to parse complex tasks into their constituents. Where such a division can be made, based say on expert judgment, there is no natural scale to measure the positive or negative values of the components. Even if we could assign numbers to task parts, we lack rules i.e., a theory, to combine them into a total task representation. We compare here two plausible theories for the amalgamation of the value of task components. Both of these theories require a numerical representation of motivation, for motivation is the primary variable that guides choice and action in well-learned tasks. We address this problem of motivational quantification and performance prediction by developing psychophysical scales of the desireability or aversiveness of task components based on utility scaling methods (Galanter 1990). We modify methods used originally to scale sensory magnitudes (Stevens and Galanter 1957), and that have been applied recently to the measure of task 'workload' by Gopher and Braune (1984). Our modification uses utility comparison scaling techniques which avoid the unnecessary assumptions made by Gopher and Braune. Formula for the utility of complex tasks based on the theoretical models are used to predict decision and choice of alternate paths to the same goal.

  14. Fiber Bragg grating sensors for strain changes measurements at volcanic sites (MED-SUV project; WP 2; Sub-Task 2.2.2)

    NASA Astrophysics Data System (ADS)

    Sorrentino, Fiodor; Beverini, Nicolò; Calamai, Massimo; Carbone, Daniele; Fotino, Nicoletta; Francesconi, Francesco; Gambino, Salvatore; Grassi, Renzo; Messin, Alfio Alex; Maccioni, Enrico; Morganti, Mauro

    2015-04-01

    Stress and strain changes at volcanic areas are recognized among the best indicators of changes in the activity of the system, and its possible evolution towards critical stages. Depending on their time evolution, stress and strain changes have been the focus of either geodetic (static changes) or seismological (dynamical changes) studies. In volcano geodesy, encouraging results have been obtained though borehole strain-meters. However, they are not easy to install and involve high costs. Therefore, the near future of strain observations at volcanoes depends on the development of broad-band sensors which are low-cost and easy to install, even in the form of dense arrays. Advancements in opto-electronics have allowed the development of low-cost sensors, reliable, rugged and compact, which are particularly suitable for on-field application. In the framework of WP 2 (New monitoring and Observing systems) of the MED-SUV project, the sub-task 2.2 involves the development of strain sensors based on the fiber Bragg grating (FBG) technology. In comparison with previous implementation of the FBG technology to study rock deformations, the system that is being developed within MED-SUV is expected to offer a significantly higher resolution and accuracy in static measurements. Moreover, a careful study is being carried out in order to obtain a smooth dynamic response up to 100 Hz, thus allowing the observation of seismic waves. Finally, the system under development will allow multi-axial strain sensing. The system performances are tailored to suit the requirements of volcano monitoring, with special attention to the trade-off between resolution and cost, and with special care to power consumption. Here we present the results of a field campaign with a preliminary, single-axis FBG strain sensor prototype on Etna, which was carried out in order to check the system performances in out-of-the-lab conditions and in the hostile volcanic environment (lack of mains electricity for

  15. Human Performance on the Temporal Bisection Task

    ERIC Educational Resources Information Center

    Kopec, Charles D.; Brody, Carlos D.

    2010-01-01

    The perception and processing of temporal information are tasks the brain must continuously perform. These include measuring the duration of stimuli, storing duration information in memory, recalling such memories, and comparing two durations. How the brain accomplishes these tasks, however, is still open for debate. The temporal bisection task,…

  16. Neural measures of a Japanese consonant length discrimination by Japanese and American English listeners: Effects of attention.

    PubMed

    Hisagi, Miwako; Shafer, Valerie L; Strange, Winifred; Sussman, Elyse S

    2015-11-11

    This study examined automaticity of discrimination of a Japanese length contrast for consonants (miʃi vs. miʃʃi) in native (Japanese) and non-native (American-English) listeners using behavioral measures and the event-related potential (ERP) mismatch negativity (MMN). Attention to the auditory input was manipulated either away from the auditory input via a visual oddball task (Visual Attend), or to the input by asking the listeners to count auditory deviants (Auditory Attend). Results showed a larger MMN when attention was focused on the consonant contrast than away from it for both groups. The MMN was larger for consonant duration increments than decrements. No difference in MMN between the language groups was observed, but the Japanese listeners did show better behavioral discrimination than the American English listeners. In addition, behavioral responses showed a weak, but significant correlation with MMN amplitude. These findings suggest that both acoustic-phonetic properties and phonological experience affects automaticity of speech processing. This article is part of a Special Issue entitled SI: Prediction and Attention. PMID:26119918

  17. Neural measures of a Japanese consonant length discrimination by Japanese and American English listeners: Effects of attention.

    PubMed

    Hisagi, Miwako; Shafer, Valerie L; Strange, Winifred; Sussman, Elyse S

    2015-11-11

    This study examined automaticity of discrimination of a Japanese length contrast for consonants (miʃi vs. miʃʃi) in native (Japanese) and non-native (American-English) listeners using behavioral measures and the event-related potential (ERP) mismatch negativity (MMN). Attention to the auditory input was manipulated either away from the auditory input via a visual oddball task (Visual Attend), or to the input by asking the listeners to count auditory deviants (Auditory Attend). Results showed a larger MMN when attention was focused on the consonant contrast than away from it for both groups. The MMN was larger for consonant duration increments than decrements. No difference in MMN between the language groups was observed, but the Japanese listeners did show better behavioral discrimination than the American English listeners. In addition, behavioral responses showed a weak, but significant correlation with MMN amplitude. These findings suggest that both acoustic-phonetic properties and phonological experience affects automaticity of speech processing. This article is part of a Special Issue entitled SI: Prediction and Attention.

  18. Critical Thinking Assessment: Measuring a Moving Target. Report & Recommendations of the South Carolina Higher Education Assessment Network Critical Thinking Task Force.

    ERIC Educational Resources Information Center

    Cook, Patricia; Johnson, Reid; Moore, Phil; Myers, Phyllis; Pauly, Susan; Pendarvis, Faye; Prus, Joe; Ulmer-Sottong, Lovely

    This report is part of South Carolina's effort to move toward "100 percent performance funding" for the state's public colleges and universities and results from a task force's investigation of ways to assess critical thinking. The following eight major findings are reported: (1) policy makers must determine priorities; (2) critical thinking lacks…

  19. Deficits in Interval Timing Measured by the Dual-Task Paradigm among Children and Adolescents with Attention-Deficit/Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Hwang, Shoou-Lian; Gau, Susan Shur-Fen; Hsu, Wen-Yau; Wu, Yu-Yu

    2010-01-01

    Background: The underlying mechanism of time perception deficit in long time intervals in attention-deficit/hyperactivity disorder (ADHD) is still unclear. This study used the time reproduction dual task to explore the role of the attentional resource in time perception deficits among children and adolescents with ADHD. Methods: Participants…

  20. The Task and Ego Orientation in Sport Questionnaire: Testing for Measurement Invariance and Latent Mean Differences in Spanish and Portuguese Adolescents

    ERIC Educational Resources Information Center

    Castillo, Isabel; Tomas, Ines; Balaguer, Isabel; Fonseca, Antonio M.; Dias, Claudia; Duda, Joan L.

    2010-01-01

    Within the theoretical framework of achievement goals (Nicholls, 1989), Duda and Nicholls (see Duda, 1989; Duda & Whitehead, 1998) developed the Task and Ego Orientation in Sport Questionnaire (TEOSQ) to assess individual differences in achievement goal orientations. This study searches for validity evidence of the TEOSQ in the case of Spanish…

  1. Electrocortical Measures during a Lexical Decision Task: A Comparison between Elementary School-Aged Normal and Dyslexic Readers and Adult Normal and Dyslexic Readers

    ERIC Educational Resources Information Center

    Miller-Shaul, Shelley; Breznitz, Zvia

    2004-01-01

    The authors examined the differences in performance between 30 dyslexic readers in 4th grade, 30 dyslexic readers attending university, and age-matched normal readers for both groups on a lexical decision task to evaluate the underlying factors of dyslexia that persist into adulthood. In both age groups, the dyslexic readers were significantly…

  2. Visual Task Demands and the Auditory Mismatch Negativity: An Empirical Study and a Meta-Analysis

    PubMed Central

    Wiens, Stefan; Szychowska, Malina; Nilsson, Mats E.

    2016-01-01

    Because the auditory system is particularly useful in monitoring the environment, previous research has examined whether task-irrelevant, auditory distracters are processed even if subjects focus their attention on visual stimuli. This research suggests that attentionally demanding visual tasks decrease the auditory mismatch negativity (MMN) to simultaneously presented auditory distractors. Because a recent behavioral study found that high visual perceptual load decreased detection sensitivity of simultaneous tones, we used a similar task (n = 28) to determine if high visual perceptual load would reduce the auditory MMN. Results suggested that perceptual load did not decrease the MMN. At face value, these nonsignificant findings may suggest that effects of perceptual load on the MMN are smaller than those of other demanding visual tasks. If so, effect sizes should differ systematically between the present and previous studies. We conducted a selective meta-analysis of published studies in which the MMN was derived from the EEG, the visual task demands were continuous and varied between high and low within the same task, and the task-irrelevant tones were presented in a typical oddball paradigm simultaneously with the visual stimuli. Because the meta-analysis suggested that the present (null) findings did not differ systematically from previous findings, the available evidence was combined. Results of this meta-analysis confirmed that demanding visual tasks reduce the MMN to auditory distracters. However, because the meta-analysis was based on small studies and because of the risk for publication biases, future studies should be preregistered with large samples (n > 150) to provide confirmatory evidence for the results of the present meta-analysis. These future studies should also use control conditions that reduce confounding effects of neural adaptation, and use load manipulations that are defined independently from their effects on the MMN. PMID:26741815

  3. Unravelling developmental disregard in children with unilateral cerebral palsy by measuring event-related potentials during a simple and complex task

    PubMed Central

    2014-01-01

    Background In a subset of children with unilateral Cerebral Palsy (CP) a discrepancy between capacity and performance of the affected upper limb can be observed. This discrepancy is known as Developmental Disregard (DD). Though the phenomenon of DD has been well documented, its underlying cause is still under debate. DD has originally been explained based on principles of operant conditioning. Alternatively, it has been proposed that DD results from a diminished automaticity of movements, resulting in an increased cognitive load when using the affected hand. To investigate the amount of involved cognitive load we studied Event-Related Potentials (ERPs) preceding task-related motor responses during a single-hand capacity and a dual-hand performance task. It was hypothesised that children with DD show alterations related to long-latency ERP components when selecting a response with the affected upper limb, reflecting increased cognitive load in order to generate an adequate response and especially so within the dual-hand task. Methods Fifteen children with unilateral CP participated in the study. One of the participants was excluded due to major visual impairments. Seven of the remaining participants displayed DD. The other seven children served as a control group. All participants performed two versions of a cue-target paradigm, a single-hand capacity and a dual-hand performance task. The ERP components linked to target presentation were inspected: the mid-latency P2 component and the consecutive long-latency N2b component. Results In the dual-hand performance task children with DD showed an enhancement in mean amplitude of the long-latency N2b component when selecting a response with their affected hand. No differences were found regarding the amplitude of the mid-latency P2 component. No differences were observed regarding the single-hand capacity task. The control group did not display any differences in ERPs linked to target evaluation processes between both

  4. Task Switching versus Cue Switching: Using Transition Cuing to Disentangle Sequential Effects in Task-Switching Performance

    ERIC Educational Resources Information Center

    Schneider, Darryl W.; Logan, Gordon D.

    2007-01-01

    Recent methodological advances have allowed researchers to address confounds in the measurement of task-switch costs in task-switching performance by dissociating cue switching from task switching. For example, in the transition-cuing procedure, which involves presenting cues for task transitions rather than for tasks, cue transitions (cue…

  5. Associations among measures of sequential processing in motor and linguistics tasks in adults with and without a family history of childhood apraxia of speech: a replication study.

    PubMed

    Button, Le; Peter, Beate; Stoel-Gammon, Carol; Raskind, Wendy H

    2013-03-01

    The purpose of this study was to address the hypothesis that childhood apraxia of speech (CAS) is influenced by an underlying deficit in sequential processing that is also expressed in other modalities. In a sample of 21 adults from five multigenerational families, 11 with histories of various familial speech sound disorders, 3 biologically related adults from a family with familial CAS showed motor sequencing deficits in an alternating motor speech task. Compared with the other adults, these three participants showed deficits in tasks requiring high loads of sequential processing, including nonword imitation, nonword reading and spelling. Qualitative error analyses in real word and nonword imitations revealed group differences in phoneme sequencing errors. Motor sequencing ability was correlated with phoneme sequencing errors during real word and nonword imitation, reading and spelling. Correlations were characterized by extremely high scores in one family and extremely low scores in another. Results are consistent with a central deficit in sequential processing in CAS of familial origin.

  6. Differential processing of natural scenes in posterior cortical atrophy and in Alzheimer’s disease, as measured with a saccade choice task

    PubMed Central

    Boucart, Muriel; Calais, Gauthier; Lenoble, Quentin; Moroni, Christine; Pasquier, Florence

    2014-01-01

    Atrophy of the medial temporal lobe structures that support scene perception and the binding of an object to its context (i.e., the hippocampus and the parahippocampal cortex) appears early in the course of Alzheimer’s disease (AD). However, few studies have investigated scene perception in people with AD. Here, we assessed the ability to find a target object within a natural scene in people with AD and in people with posterior cortical atrophy (PCA, a variant of AD). Pairs of color photographs were displayed on the left and right of a fixation cross for 1 s. In separate blocks of trials, participants were asked to categorize the target (an animal) by either moving their eyes toward the photograph containing the target (the saccadic choice task) or pressing a key corresponding to the target’s location (the manual choice task). Isolated objects and objects within scenes were studied in both tasks. Participants with PCA were more impaired in detection of a target within a scene than participants with AD. The latter’s performance pattern was more similar to that of age-matched controls in terms of accuracy, saccade latencies and the benefit gained from contextual information. Participants with PCA benefited less from contextual information in both the saccade and the manual choice tasks—suggesting that people with posterior brain lesions have impairments in figure/ground segregation and are more sensitive to object crowding. PMID:25120440

  7. EEG anomalies in adult ADHD subjects performing a working memory task.

    PubMed

    Missonnier, P; Hasler, R; Perroud, N; Herrmann, F R; Millet, P; Richiardi, J; Malafosse, A; Giannakopoulos, P; Baud, P

    2013-06-25

    Functional imaging studies have revealed differential brain activation patterns in attention deficit hyperactivity disorder (ADHD) adult patients performing working memory (WM) tasks. The existence of alterations in WM-related cortical circuits during childhood may precede executive dysfunctions in this disorder in adults. To date, there is no study exploring the electrophysiological activation of WM-related neural networks in ADHD. To address this issue, we carried out an electroencephalographic (EEG) activation study associated with time-frequency (TF) analysis in 15 adults with ADHD and 15 controls performing two visual N-back WM tasks, as well as oddball detection and passive fixation tasks. Frontal transient (phasic) theta event-related synchronization (ERS, 0-500 msec) was significantly reduced in ADHD as compared to control subjects. Such reduction was equally present in a task-independent manner. In contrast, the power of the later sustained (∼500-1200 msec) theta ERS for all tasks was comparable in ADHD and control groups. In active WM tasks, ADHD patients displayed lower alpha event-related desynchronization (ERD, ∼200-900 msec) and higher subsequent alpha ERS (∼900-2400 msec) compared to controls. The time course of alpha ERD/ERS cycle was modified in ADHD patients compared to controls, suggesting that they are able to use late compensatory mechanisms in order to perform this WM task. These findings support the idea of an ADHD-related dysfunction of neural generators sub-serving attention directed to the incoming visual information. ADHD cases may successfully face WM needs depending on the preservation of sustained theta ERS and prolonged increase of alpha ERS at later post-stimulus time points. PMID:23518223

  8. Developmental changes in using verbal self-cueing in task-switching situations: the impact of task practice and task-sequencing demands.

    PubMed

    Kray, Jutta; Gaspard, Hanna; Karbach, Julia; Blaye, Agnès

    2013-01-01

    In this study we examined whether developmental changes in using verbal self-cueing for task-goal maintenance are dependent on the amount of task practice and task-sequencing demands. To measure task-goal maintenance we applied a switching paradigm in which children either performed only task A or B in single-task blocks or switched between them on every second trial in mixed-task blocks. Task-goal maintenance was determined by comparing the performance between both blocks (mixing costs). The influence of verbal self-cueing was measured by instructing children to either name the next task aloud or not to verbalize during task preparation. Task-sequencing demands were varied between groups whereas one group received spatial task cues to support keeping track of the task sequence, while the other group did not. We also varied by the amount of prior practice in task switching while one group of participants practiced task switching first, before performing the task naming in addition, and the other group did it vice versa. Results of our study investigating younger (8-10 years) and older children (11-13 years) revealed no age differences in beneficial effects of verbal self-cueing. In line with previous findings, children showed reduced mixing costs under task-naming instructions and under conditions of low task-sequence demands (with the presence of spatial task cues). Our results also indicated that these benefits were only obtained for those groups of children that first received practice in task switching alone with no additional verbalization instruction. These findings suggest that internal task-cueing strategies can be efficiently used in children but only if they received prior practice in the underlying task so that demands on keeping and coordinating various instructions are reduced. Moreover, children benefitted from spatial task cues for better task-goal maintenance only if no verbal task-cueing strategy was introduced first. PMID:24381566

  9. Recalling academic tasks

    NASA Astrophysics Data System (ADS)

    Draper, Franklin Gno

    This study was focused on what students remembered about five middle school science tasks when they were juniors and seniors in high school. Descriptions of the five tasks were reconstructed from available artifacts and teachers' records, notes and recollections. Three of the five tasks were "authentic" in the sense that students were asked to duplicate the decisions practitioners make in the adult world. The other two tasks were more typical school tasks involving note taking and preparation for a quiz. All five tasks, however, involved use of computers. Students were interviewed to examine what and how well they recalled the tasks and what forms or patterns of recall existed. Analysis of their responses indicated that different kinds of tasks produced different levels of recall. Authentically situated tasks were remembered much better than routine school tasks. Further, authentic tasks centered on design elements were recalled better than those for which design was not as pivotal. Patterns of recall indicated that participants most often recalled the decisions they made, the scenarios of the authentically situated tasks, the consequences of their tasks and the social contexts of the classroom. Task events, in other words, appeared to form a framework upon which students constructed stories of the tasks. The more salient the events, the richer the story, the deeper and more detailed the recall of the task. Thus, authentic tasks appeared to lend themselves to creating stories better than regular school tasks and therefore such tasks were recalled better. Implications of these patterns of recall are discussed with respect to issues of school learning and assessment.

  10. Introduction to meteorological measurements and data handling for solar energy applications. Task IV. Development of an isolation handbook and instrument package

    SciTech Connect

    1980-01-01

    The following are covered: the Sun and its radiation, solar radiation and atmospheric interaction, solar radiation measurement methods, spectral irradiance measurements of natural sources, the measurement of infrared radiation, the measurement of circumsolar radiation, some empirical properties of solar radiation and related parameters, duration of sunshine, and meteorological variables related to solar energy. Included in appendices are manufacturers and distributors of solar radiation measuring instruments and an approximate method for quality control of solar radiation instruments. (MHR)

  11. Safety-critical event risk associated with cell phone tasks as measured in naturalistic driving studies: A systematic review and meta-analysis.

    PubMed

    Simmons, Sarah M; Hicks, Anne; Caird, Jeff K

    2016-02-01

    A systematic review and meta-analysis of naturalistic driving studies involving estimates of safety-critical event risk associated with handheld device use while driving is described. Fifty-seven studies identified from targeted databases, journals and websites were reviewed in depth, and six were ultimately included. These six studies, published between 2006 and 2014, encompass seven sets of naturalistic driver data and describe original research that utilized naturalistic methods to assess the effects of distracting behaviors. Four studies involved non-commercial drivers of light vehicles and two studies involved commercial drivers of trucks and buses. Odds ratios quantifying safety-critical event (SCE) risk associated with talking, dialing, locating or answering, and texting or browsing were extracted. Stratified meta-analysis of pooled odds ratios was used to estimate SCE risk by distraction type; meta-regression was used to test for sources of heterogeneity. The results indicate that tasks that require drivers to take their eyes off the road, such as dialing, locating a phone and texting, increase SCE risk to a greater extent than tasks that do not require eyes off the road such as talking. Although talking on a handheld device did not increase SCE risk, further research is required to determine whether it indirectly influences SCE risk (e.g., by encouraging other cell phone activities). In addition, a number of study biases and quality issues of naturalistic driving studies are discussed. PMID:26724505

  12. Mobile EEG on the bike: disentangling attentional and physical contributions to auditory attention tasks

    NASA Astrophysics Data System (ADS)

    Zink, Rob; Hunyadi, Borbála; Van Huffel, Sabine; De Vos, Maarten

    2016-08-01

    Objective. In the past few years there has been a growing interest in studying brain functioning in natural, real-life situations. Mobile EEG allows to study the brain in real unconstrained environments but it faces the intrinsic challenge that it is impossible to disentangle observed changes in brain activity due to increase in cognitive demands by the complex natural environment or due to the physical involvement. In this work we aim to disentangle the influence of cognitive demands and distractions that arise from such outdoor unconstrained recordings. Approach. We evaluate the ERP and single trial characteristics of a three-class auditory oddball paradigm recorded in outdoor scenario’s while peddling on a fixed bike or biking freely around. In addition we also carefully evaluate the trial specific motion artifacts through independent gyro measurements and control for muscle artifacts. Main results. A decrease in P300 amplitude was observed in the free biking condition as compared to the fixed bike conditions. Above chance P300 single-trial classification in highly dynamic real life environments while biking outdoors was achieved. Certain significant artifact patterns were identified in the free biking condition, but neither these nor the increase in movement (as derived from continuous gyrometer measurements) can explain the differences in classification accuracy and P300 waveform differences with full clarity. The increased cognitive load in real-life scenarios is shown to play a major role in the observed differences. Significance. Our findings suggest that auditory oddball results measured in natural real-life scenarios are influenced mainly by increased cognitive load due to being in an unconstrained environment.

  13. Functional Task Test (FTT)

    NASA Technical Reports Server (NTRS)

    Bloomberg, Jacob J.; Mulavara, Ajitkumar; Peters, Brian T.; Rescheke, Millard F.; Wood, Scott; Lawrence, Emily; Koffman, Igor; Ploutz-Snyder, Lori; Spiering, Barry A.; Feeback, Daniel L.; Platts, Steven H.; Stenger, Michael B.; Lee, Stuart M.C.; Arzeno, Natalia; Feiveson, Alan H.; Ryder, Jeffrey; Garcia, Yamil; Guilliams, Mark E.

    2009-01-01

    This slide presentation reviews the Functional Task Test (FTT), an interdisciplinary testing regimen that has been developed to evaluate astronaut postflight functional performance and related physiological changes. The objectives of the project are: (1) to develop a set of functional tasks that represent critical mission tasks for the Constellation Program, (2) determine the ability to perform these tasks after space flight, (3) Identify the key physiological factors that contribute to functional decrements and (4) Use this information to develop targeted countermeasures.

  14. Assessment of conditioning-specific movement tasks and physical fitness measures in talent identified under 16-year-old rugby union players.

    PubMed

    Parsonage, Joanna R; Williams, Rhodri S; Rainer, Paul; McKeown, Ian; Williams, Morgan D

    2014-06-01

    Preparedness to train was assessed using a battery of conditioning-specific movement tasks (CSMTs) on a group of talent identified rugby union players (n = 156; age = 15 ± 7 years; stature = 176 ± 7 cm; and mass = 74 ± 14 kg). In addition to explore the link between movement competency and performance, a series of standard fitness tests was conducted. Overall the group's CSMTs competency ratings were low, but task dependent. The proportion of competent players ranged from 14% for a single leg squat to 70% for a double to single leg landing. Players were subsequently grouped based on their CSMTs ratings using cluster analysis. This analysis classified players on features of the CSMT battery that distinguished between groups rather than an arbitrary score. Fitness test scores were then compared between the 3 groups identified. The "general low competency" group jumped 9.1 cm lower (p = 0.0218), sprinted slower across 10, 20 and 40 m (range, p = 0.0126-0.0018) and covered 389 m less (p = 0.0105) Yo-Yo intermittent recovery level 1 distance compared with the "squat competent group." In summary, at this important time before academy selection, most players could not competently perform the CSMTs that underpin rugby conditioning and may not be prepared for the transition into the "training to compete" stage of the suggested long-term athlete development model. For this sample of players, the athlete development process may therefore be unnecessarily inhibited. Moreover, our observations that competency in some CSMTs may explain better running and jumping performances in some players suggest that a focus on monitoring and addressing movement competencies during the training to train stage of player development should be considered.

  15. Task Time Tracker

    2013-07-24

    This client-side web app tracks the amount of time spent on arbitrary tasks. It allosw the creation of an unlimited number of arbitrarily named tasks ans via simple interactions, tracks the amount of time spent working on the drfined tasks.

  16. Launching Complex Tasks

    ERIC Educational Resources Information Center

    Jackson, Kara J.; Shahan, Emily C.; Gibbons, Lynsey K.; Cobb, Paul A.

    2012-01-01

    Mathematics lessons can take a variety of formats. In this article, the authors discuss lessons organized around complex mathematical tasks. These lessons usually unfold in three phases. First, the task is introduced to students. Second, students work on solving the task. Third, the teacher "orchestrates" a concluding whole-class discussion in…

  17. INITIAL VALIDATION OF THE ASSESSMENT OF PARENTING TOOL: A TASK- AND DOMAIN-LEVEL MEASURE OF PARENTING SELF-EFFICACY FOR PARENTS OF INFANTS FROM BIRTH TO 24 MONTHS OF AGE.

    PubMed

    Moran, Tracy E; Polanin, Joshua R; Evenson, Amber L; Troutman, Beth R; Franklin, Christina L

    2016-05-01

    Parenting self-efficacy (PSE) includes parents' self-perceptions regarding their capabilities in performing the numerous and changing tasks associated with parenting a specific child (i.e., domain-specific PSE) as well as their self-perceptions in the parenting role overall (i.e., domain-general PSE). Prior literature has demonstrated PSE's relations with numerous constructs significant to mental health and the parent-infant relationship. Prior measures of PSE have been limited by focusing on only domain-specific or domain-general PSE, ignoring the importance of infant development to PSE, and other psychometric limitations. This article presents sound psychometric data for a new measure of PSE, the Assessment of Parenting Tool (APT). The APT includes task-level items on the Domain-Specific subscale (APT-DS) for each age-referenced version of the measure as well as a domain-general subscale that taps overall PSE within the first 24 months' postpartum. Initial construct validity of the measure is established, particularly for parents of infants aged 3 months and older. A stable, three-factor structure for the domain-general subscale includes "coping with being a parent," "attuned parenting," and "self-perceived model parenting." Future directions for the APT, including a revised checklist format for the domain-specific subscale, are included.

  18. Grid Task Execution

    NASA Technical Reports Server (NTRS)

    Hu, Chaumin

    2007-01-01

    IPG Execution Service is a framework that reliably executes complex jobs on a computational grid, and is part of the IPG service architecture designed to support location-independent computing. The new grid service enables users to describe the platform on which they need a job to run, which allows the service to locate the desired platform, configure it for the required application, and execute the job. After a job is submitted, users can monitor it through periodic notifications, or through queries. Each job consists of a set of tasks that performs actions such as executing applications and managing data. Each task is executed based on a starting condition that is an expression of the states of other tasks. This formulation allows tasks to be executed in parallel, and also allows a user to specify tasks to execute when other tasks succeed, fail, or are canceled. The two core components of the Execution Service are the Task Database, which stores tasks that have been submitted for execution, and the Task Manager, which executes tasks in the proper order, based on the user-specified starting conditions, and avoids overloading local and remote resources while executing tasks.

  19. Application of task-based measures of image quality to optimization and evaluation of three-dimensional reconstruction-based compensation methods in myocardial perfusion SPECT.

    PubMed

    Frey, Eric C; Gilland, Karen L; Tsui, Benjamin M W

    2002-09-01

    In this paper, we apply the channelized Hotelling observer (CHO) using a defect detection task to the optimization and evaluation of three-dimensional iterative reconstruction-based compensation methods for myocardial perfusion single-photon emission computed tomography (SPECT). We used a population of 24 mathematical cardiac-torso phantoms that realistically model the activity and attenuation distribution in three classes of patients: females, and males with flat diaphragms and raised diaphragms. Projection data were generated and subsequently reconstructed using methods based on the ordered subsets-expectation maximization (OSEM) algorithm. The methods evaluated included compensation for attenuation, detector response blurring, and scatter in various combinations. We applied the CHO to optimize the number of iterations for OSEM and the cutoff frequency and order of a three-dimensional postreconstruction Butterworth filter. Using the optimal parameters, we then compared the compensation methods. The index of comparison in these studies was the area under the receiver operating characteristics curve (AUC) for the CHO. We found that attenuation compensation with either detector response or scatter compensation gave statistically significant increases in the AUC compared to attenuation compensation alone. The greatest increase in the AUC occurred when all three compensations were applied. These results indicate that compensation for detector response and scatter, in addition to attenuation compensation, will improve defect detectability in myocardial SPECT images.

  20. Behavior of testosterone and cortisol during an intensity-controlled high-volume training period measured by a training task-specific test in men rowers.

    PubMed

    Rämson, Raul; Jürimäe, Jaak; Jürimäe, Toivo; Mäestu, Jarek

    2009-03-01

    The aim of this study was to investigate changes in the stress hormones testosterone and cortisol after a task-specific exercise during a high-volume endurance training cycle in men rowers. Eight highly trained men rowers were investigated during a high-volume, low-intensity training period. A 2-hour, low-intensity, long-distance rowing (LDT) test was conducted at baseline, after a high-volume period, and after the recovery period. Training and performance intensities were obtained at the graded incremental test, were preset individually, and were the same during all LDTs. Fasting blood samples were taken during the same days as the LDTs. Exercise-induced blood samples were taken before, 5 minutes after, and 30 minutes after (post 30') the completion of each LDT. There were no significant changes in fasting cortisol and testosterone values during the whole study period, and there were no significant changes in cortisol and testosterone concentrations during the LDT. However, testosterone concentration was significantly decreased at post 30' compared with posttest values during the second LDT that was held after the 2-week high-training-volume period, and, during the second LDT, post 30' values of cortisol tended to be decreased compared with posttest values (p = 0.063). In conclusion, changes in the concentrations of testosterone and cortisol after long-distance rowing indicate decreased adaptivity after the training-specific performance test.

  1. Studies related to ocean dynamics. Task 3.2: Aircraft Field Test Program to investigate the ability of remote sensing methods to measure current/wind-wave interactions

    NASA Technical Reports Server (NTRS)

    Huang, N. E.; Flood, W. A.; Brown, G. S.

    1975-01-01

    The feasibility of remote sensing of current flows in the ocean and the remote sensing of ocean currents by backscattering cross section techniques was studied. It was established that for capillary waves, small scale currents could be accurately measured through observation of wave kinematics. Drastic modifications of waves by changing currents were noted. The development of new methods for the measurement of capillary waves are discussed. Improvement methods to resolve data processing problems are suggested.

  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. The Effect of N-3 on N-2 Repetition Costs in Task Switching

    ERIC Educational Resources Information Center

    Schuch, Stefanie; Grange, James A.

    2015-01-01

    N-2 task repetition cost is a response time and error cost returning to a task recently performed after one intervening trial (i.e., an ABA task sequence) compared with returning to a task not recently performed (i.e., a CBA task sequence). This cost is considered a robust measure of inhibitory control during task switching. The present article…

  5. Shaping Academic Task Engagement with Percentile Schedules

    ERIC Educational Resources Information Center

    Athens, Elizabeth S.; Vollmer, Timothy R.; St. Peter Pipkin, Claire C.

    2007-01-01

    The purpose of this study was to examine the use of percentile schedules as a method of quantifying the shaping procedure in an educational setting. We compared duration of task engagement during baseline measurements for 4 students to duration of task engagement during a percentile schedule. As a secondary purpose, we examined the influence on…

  6. A comparison of rating scale, secondary-task, physiological, and primary-task workload estimation techniques in a simulated flight task emphasizing communications load

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

    Sixteen potential metrics of pilot mental workload were investigated regarding their sensitivity to communication load and their intrusion on primary-task performance. A moving-base flight simulator was used to present three cross-country flights. The flights varied only in the difficulty of the communications requirements. Rating scale measures were obtained immediately postflight; all others were taken over a 7-min segment of the flight task. The results indicated that both the Modified Cooper-Harper Scale and the workload Multi-descriptor Scale were sensitive to changes in communications load. The secondary-task measure of time estimation and the physiological measure of pupil diameter were also sensitive. As expected, those primary-task measures that were direct measures of communicative performance were also sensitive to load, whereas aicraft control primary-task measures were not, attesting to the task specificity of such measures. Finally, the intrusion analysis revealed no differential interference between workload measures.

  7. NSI security task: Overview

    NASA Technical Reports Server (NTRS)

    Tencati, Ron

    1991-01-01

    An overview is presented of the NASA Science Internet (NSI) security task. The task includes the following: policies and security documentation; risk analysis and management; computer emergency response team; incident handling; toolkit development; user consulting; and working groups, conferences, and committees.

  8. A Computational Linguistic Measure of Clustering Behavior on Semantic Verbal Fluency Task Predicts Risk of Future Dementia in the Nun Study

    PubMed Central

    Pakhomov, Serguei V.S.; Hemmy, Laura S.

    2014-01-01

    Generative semantic verbal fluency (SVF) tests show early and disproportionate decline relative to other abilities in individuals developing Alzheimer’s disease. Optimal performance on SVF tests depends on the efficiency of using clustered organization of semantically related items and the ability to switch between clusters. Traditional approaches to clustering and switching have relied on manual determination of clusters. We evaluated a novel automated computational linguistic approach for quantifying clustering behavior. Our approach is based on Latent Semantic Analysis (LSA) for computing strength of semantic relatedness between pairs of words produced in response to SVF test. The mean size of semantic clusters (MCS) and semantic chains (MChS) are calculated based on pairwise relatedness values between words. We evaluated the predictive validity of these measures on a set of 239 participants in the Nun Study, a longitudinal study of aging. All were cognitively intact at baseline assessment, measured with the CERAD battery, and were followed in 18 month waves for up to 20 years. The onset of either dementia or memory impairment were used as outcomes in Cox proportional hazards models adjusted for age and education and censored at follow up waves 5 (6.3 years) and 13 (16.96 years). Higher MCS was associated with 38% reduction in dementia risk at wave 5 and 26% reduction at wave 13, but not with the onset of memory impairment. Higher (+1 SD) MChS was associated with 39% dementia risk reduction at wave 5 but not wave 13, and association with memory impairment was not significant. Higher traditional SVF scores were associated with 22–29% memory impairment and 35–40% dementia risk reduction. SVF scores were not correlated with either MCS or MChS. Our study suggests that an automated approach to measuring clustering behavior can be used to estimate dementia risk in cognitively normal individuals. PMID:23845236

  9. Task Description Language

    NASA Technical Reports Server (NTRS)

    Simmons, Reid; Apfelbaum, David

    2005-01-01

    Task Description Language (TDL) is an extension of the C++ programming language that enables programmers to quickly and easily write complex, concurrent computer programs for controlling real-time autonomous systems, including robots and spacecraft. TDL is based on earlier work (circa 1984 through 1989) on the Task Control Architecture (TCA). TDL provides syntactic support for hierarchical task-level control functions, including task decomposition, synchronization, execution monitoring, and exception handling. A Java-language-based compiler transforms TDL programs into pure C++ code that includes calls to a platform-independent task-control-management (TCM) library. TDL has been used to control and coordinate multiple heterogeneous robots in projects sponsored by NASA and the Defense Advanced Research Projects Agency (DARPA). It has also been used in Brazil to control an autonomous airship and in Canada to control a robotic manipulator.

  10. Age Differences between Children and Young Adults in the Dynamics of Dual-Task Prioritization: Body (Balance) versus Mind (Memory)

    ERIC Educational Resources Information Center

    Schaefer, Sabine; Krampe, Ralf Th.; Lindenberger, Ulman; Baltes, Paul B.

    2008-01-01

    Task prioritization can lead to trade-off patterns in dual-task situations. The authors compared dual-task performances in 9- and 11-year-old children and young adults performing a cognitive task and a motor task concurrently. The motor task required balancing on an ankle-disc board. Two cognitive tasks measured working memory and episodic memory…

  11. Hypercube matrix computation task

    NASA Technical Reports Server (NTRS)

    Calalo, R.; Imbriale, W.; Liewer, P.; Lyons, J.; Manshadi, F.; Patterson, J.

    1987-01-01

    The Hypercube Matrix Computation (Year 1986-1987) task investigated the applicability of a parallel computing architecture to the solution of large scale electromagnetic scattering problems. Two existing electromagnetic scattering codes were selected for conversion to the Mark III Hypercube concurrent computing environment. They were selected so that the underlying numerical algorithms utilized would be different thereby providing a more thorough evaluation of the appropriateness of the parallel environment for these types of problems. The first code was a frequency domain method of moments solution, NEC-2, developed at Lawrence Livermore National Laboratory. The second code was a time domain finite difference solution of Maxwell's equations to solve for the scattered fields. Once the codes were implemented on the hypercube and verified to obtain correct solutions by comparing the results with those from sequential runs, several measures were used to evaluate the performance of the two codes. First, a comparison was provided of the problem size possible on the hypercube with 128 megabytes of memory for a 32-node configuration with that available in a typical sequential user environment of 4 to 8 megabytes. Then, the performance of the codes was anlyzed for the computational speedup attained by the parallel architecture.

  12. The relational integration task explains fluid reasoning above and beyond other working memory tasks.

    PubMed

    Chuderski, Adam

    2014-04-01

    This study aimed to evaluate how well fluid reasoning can be predicted by a task that involves the monitoring of patterns of stimuli. This task is believed to measure the effectiveness of relational integration-the process that binds mental representations into more complex relational structures. In Experiments 1 and 2, the task was indeed validated as a proper measure of relational integration, since participants' performance depended on the number of bindings that had to be constructed in the diverse conditions of the task, whereas neither the number of objects to be bound nor the amount of elicited interference could affect this performance. In Experiment 3, by means of structural equation modeling and variance partitioning, the relation integration task was found to be the strongest predictor of fluid reasoning, explaining variance above and beyond the amounts accounted for by four other kinds of well-established working memory tasks.

  13. Development of sensors based on the fiber Bragg grating technology to measure strain changes at volcanoes (MED-SUV project; WP 2; Sub-Task 2.2.2)

    NASA Astrophysics Data System (ADS)

    Beverini, Nicolò; Calamai, Massimo; Carbone, Daniele; Francesconi, Francesco; Gambino, Salvo; Grassi, Renzo; Messina, Alfio Alex; Maccioni, Enrico; Morganti, Mauro; Sorrentino, Fiodor

    2014-05-01

    Stress and strain changes at volcanic areas are recognized among the best indicators of changes in the activity of the system, and its possible evolution towards critical stages. Depending on their time evolution, stress and strain changes have been the focus of either geodetic (static changes) or seismological (dynamical changes) studies. In volcano geodesy, encouraging results have been obtained though borehole strain-meters. However, they are not easy to install and involve high costs. Therefore, the near future of strain observations at volcanoes depends on the development of broad-band sensors which are low-cost and easy to install, even in the form of dense arrays. Advancements in opto-electronics have allowed the development of low-cost sensors, reliable, rugged and compact, which are particularly suitable for on-field application. In the framework of WP 2 (New monitoring and Observing systems) of the MED-SUV project, the sub-task 2.2 involves the development of strain sensors based on the fiber Bragg grating (FBG) technology. In comparison with previous implementation of the FBG technology to study rock deformations, the system that is being developed within MED-SUV is expected to offer a significantly higher resolution and accuracy in static measurements. Moreover, a careful study will be carried out in order to obtain a smooth dynamic response up to 100 Hz, thus allowing the observation of seismic waves. Finally, strategies to implement a tri-axial configuration will be studied. The performances of the proposed systems will be tailored to suit the requirements of volcano monitoring, with special attention to the trade-off between resolution and cost. Here we present an overview of FBG technology applied to strain measurement, the main objectives of our sub-task in the framework of MED-SUV and some preliminary data from a test installation on Etna.

  14. Reduced specificity of functional connectivity in the aging brain during task performance.

    PubMed

    Geerligs, Linda; Maurits, Natasha M; Renken, Remco J; Lorist, Monicque M

    2014-01-01

    The importance of studying connectivity in the aging brain is increasingly recognized. Recent studies have shown that connectivity within the default mode network is reduced with age and have demonstrated a clear relation of these changes with cognitive functioning. However, research on age-related changes in other functional networks is sparse and mainly focused on prespecified functional networks. Using functional magnetic resonance imaging, we investigated age-related changes in functional connectivity during a visual oddball task in a range of functional networks. It was found that compared with young participants, elderly showed a decrease in connectivity between areas belonging to the same functional network. This was found in the default mode network and the somatomotor network. Moreover, in all identified networks, elderly showed increased connectivity between areas within these networks and areas belonging to different functional networks. Decreased connectivity within functional networks was related to poorer cognitive functioning in elderly. The results were interpreted as a decrease in the specificity of functional networks in older participants.

  15. Task Analysis for Health Occupations. Cluster: Medical Assisting. Occupation: Medical Assistant. Education for Employment Task Lists.

    ERIC Educational Resources Information Center

    Lathrop, Janice

    Task analyses are provided for two duty areas for the occupation of medical assistant in the medical assisting cluster. Five tasks for the duty area "providing therapeutic measures" are as follows: assist with dressing change, apply clean dressing, apply elastic bandage, assist physician in therapeutic procedure, and apply topical ointment. The…

  16. Across-Task Priming Revisited: Response and Task Conflicts Disentangled Using Ex-Gaussian Distribution Analysis

    ERIC Educational Resources Information Center

    Moutsopoulou, Karolina; Waszak, Florian

    2012-01-01

    The differential effects of task and response conflict in priming paradigms where associations are strengthened between a stimulus, a task, and a response have been demonstrated in recent years with neuroimaging methods. However, such effects are not easily disentangled with only measurements of behavior, such as reaction times (RTs). Here, we…

  17. Task Switching in a Hierarchical Task Structure: Evidence for the Fragility of the Task Repetition Benefit

    ERIC Educational Resources Information Center

    Lien, Mei-Ching; Ruthruff, Eric

    2004-01-01

    This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms.…

  18. 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

  19. A change of task prolongs early processes: evidence from ERPs in lexical tasks.

    PubMed

    Elchlepp, Heike; Lavric, Aureliu; Monsell, Stephen

    2015-04-01

    Switching tasks costs time. Allowing time to prepare reduces the cost, but usually leaves an irreducible "residual cost." Most accounts of this residual cost locate it within the response-selection stage of processing. To determine which processing stage is affected, we measured event-related potentials (ERPs) as participants performed a reading task or a perceptual judgment task, and examined the effect of a task switch on early markers of lexical processing. A task cue preceding a string of blue and red letters instructed the participant either to read the letter string (for a semantic classification in Experiment 1, and a lexical decision in Experiment 2) or to judge the symmetry of its color pattern. In Experiment 1, having to switch to the reading task delayed the evolution of the effect of word frequency on the reading task ERP by a substantial fraction of the effect on reaction time (RT). In Experiment 2, a task switch delayed the onset of the effect of lexical status on the ERP by about the same extent that it prolonged the RT. These effects indicate an early locus of (most of) the residual switch cost: We propose that this reflects a form of task-related attentional inertia. Other findings have implications for the automaticity of lexical access: Effects of frequency, lexicality, and orthographic familiarity on ERPs in the symmetry task indicated involuntary, but attenuated, orthographic and lexical processing even when attention was focused on a nonlexical property. PMID:25844623

  20. A change of task prolongs early processes: evidence from ERPs in lexical tasks.

    PubMed

    Elchlepp, Heike; Lavric, Aureliu; Monsell, Stephen

    2015-04-01

    Switching tasks costs time. Allowing time to prepare reduces the cost, but usually leaves an irreducible "residual cost." Most accounts of this residual cost locate it within the response-selection stage of processing. To determine which processing stage is affected, we measured event-related potentials (ERPs) as participants performed a reading task or a perceptual judgment task, and examined the effect of a task switch on early markers of lexical processing. A task cue preceding a string of blue and red letters instructed the participant either to read the letter string (for a semantic classification in Experiment 1, and a lexical decision in Experiment 2) or to judge the symmetry of its color pattern. In Experiment 1, having to switch to the reading task delayed the evolution of the effect of word frequency on the reading task ERP by a substantial fraction of the effect on reaction time (RT). In Experiment 2, a task switch delayed the onset of the effect of lexical status on the ERP by about the same extent that it prolonged the RT. These effects indicate an early locus of (most of) the residual switch cost: We propose that this reflects a form of task-related attentional inertia. Other findings have implications for the automaticity of lexical access: Effects of frequency, lexicality, and orthographic familiarity on ERPs in the symmetry task indicated involuntary, but attenuated, orthographic and lexical processing even when attention was focused on a nonlexical property.

  1. Instructional Cues Modify Performance on the Iowa Gambling Task

    ERIC Educational Resources Information Center

    Balodis, Iris M.; MacDonald, Tara K.; Olmstead, Mary C.

    2006-01-01

    The current study investigated whether acute alcohol intoxication produces impaired decision-making on tasks assessing ventromedial prefrontal (VMF) cortex functioning and impulsive responding. Participants completed the Iowa Gambling Task (IGT), a decision-making test targeting the VMF, and the Newman Perseveration Task (NT), a measure of…

  2. The Work Tasks Motivation Scale for Teachers (WTMST)

    ERIC Educational Resources Information Center

    Fernet, Claude; Senecal, Caroline; Guay, Frederic; Marsh, Herbert; Dowson, Martin

    2008-01-01

    The authors developed and validated a measure of teachers' motivation toward specific work tasks: The Work Tasks Motivation Scale for Teachers (WTMST). The WTMST is designed to assess five motivational constructs toward six work tasks (e.g., class preparation, teaching). The authors conducted a preliminary (n = 42) and a main study among…

  3. The Impact of Assessment Tasks on Subsequent Examination Performance

    ERIC Educational Resources Information Center

    Van Gaal, Frank; De Ridder, Annemieke

    2013-01-01

    In this article, the impact of assessment tasks on examination result (measured by examination grades) is investigated. Although many describe the advantages of electronic assessment tasks, few studies have been undertaken which compare a traditional approach using a classical examination with a new approach using assessment tasks. The main…

  4. Brief report: manipulation of task difficulty in inhibitory control tasks.

    PubMed

    Lindqvist, Sofia; Thorell, Lisa B

    2009-01-01

    The present study investigated how task difficulty can be manipulated in inhibitory control tasks. Tasks from three widely used task paradigms - a Go/No-Go task, a Stop-Signal task,and a Flanker task - were manipulated on two parameters each (Go/No-Go task: interstimulus interval, prepotency. Stop-signal task: stop-signal-delay, prepotency. Flanker task:number of distractors, size of target stimulus). Participants were 86 children (age 4-6) from a population-based sample. The results showed no significant effects on the Go/No-Go task but both main and interaction effects on the Stop-Signal task and the Flanker task. Together, these findings indicate that task difficulty can be successfully manipulated in inhibitory control tasks. However, the interactive rather than additive effects on performance suggest that the level of one parameter only has the desired effect under certain conditions. This new information about how to manipulate task difficulty is important when adapting tasks for use with children of different ages, as well as when designing training programs for improving inhibitory control among children with ADHD. PMID:18608218

  5. Task-Based Learning: The Interaction between Tasks and Learners.

    ERIC Educational Resources Information Center

    Murphy, Jacky

    2003-01-01

    Investigates the relationship between tasks and learners in task-based learning. Findings suggest that manipulation of task characteristics and conditions may not achieve the intended pedagogic outcomes, and that new ways are needed to focus learners' attention of form without sacrificing the meaning-driven principles of task-based learning.…

  6. Mind wandering in text comprehension under dual-task conditions.

    PubMed

    Dixon, Peter; Li, Henry

    2013-01-01

    In two experiments, subjects responded to on-task probes while reading under dual-task conditions. The secondary task was to monitor the text for occurrences of the letter e. In Experiment 1, reading comprehension was assessed with a multiple-choice recognition test; in Experiment 2, subjects recalled the text. In both experiments, the secondary task replicated the well-known "missing-letter effect" in which detection of e's was less effective for function words and the word "the." Letter detection was also more effective when subjects were on task, but this effect did not interact with the missing-letter effect. Comprehension was assessed in both the dual-task conditions and in control single-task conditions. In the single-task conditions, both recognition (Experiment 1) and recall (Experiment 2) was better when subjects were on task, replicating previous research on mind wandering. Surprisingly, though, comprehension under dual-task conditions only showed an effect of being on task when measured with recall; there was no effect on recognition performance. Our interpretation of this pattern of results is that subjects generate responses to on-task probes on the basis of a retrospective assessment of the contents of working memory. Further, we argue that under dual-task conditions, the contents of working memory is not closely related to the reading processes required for accurate recognition performance. These conclusions have implications for models of text comprehension and for the interpretation of on-task probe responses.

  7. Embodied Task Dynamics

    ERIC Educational Resources Information Center

    Simko, Juraj; Cummins, Fred

    2010-01-01

    Movement science faces the challenge of reconciling parallel sequences of discrete behavioral goals with observed fluid, context-sensitive motion. This challenge arises with a vengeance in the speech domain, in which gestural primitives play the role of discrete goals. The task dynamic framework has proved effective in modeling the manner in which…

  8. Biomedical applications engineering tasks

    NASA Technical Reports Server (NTRS)

    Laenger, C. J., Sr.

    1976-01-01

    The engineering tasks performed in response to needs articulated by clinicians are described. Initial contacts were made with these clinician-technology requestors by the Southwest Research Institute NASA Biomedical Applications Team. The basic purpose of the program was to effectively transfer aerospace technology into functional hardware to solve real biomedical problems.

  9. Creating Positive Task Constraints

    ERIC Educational Resources Information Center

    Mally, Kristi K.

    2006-01-01

    Constraints are characteristics of the individual, the task, or the environment that mold and shape movement choices and performances. Constraints can be positive--encouraging proficient movements or negative--discouraging movement or promoting ineffective movements. Physical educators must analyze, evaluate, and determine the effect various…

  10. Chizu Task Mapping Tool

    SciTech Connect

    2014-07-01

    Chizu is a tool for Mapping MPI processes or tasks to physical processors or nodes for optimizing communication performance. It takes the communication graph of a High Performance Computing (HPC) application and the interconnection topology of a supercomputer as input. It outputs a new MPI rand to processor mapping, which can be used when launching the HPC application.

  11. Randomization in robot tasks

    NASA Technical Reports Server (NTRS)

    Erdmann, Michael

    1992-01-01

    This paper investigates the role of randomization in the solution of robot manipulation tasks. One example of randomization is shown by the strategy of shaking a bin holding a part in order to orient the part in a desired stable state with some high probability. Randomization can be useful for mobile robot navigation and as a means of guiding the design process.

  12. Project Echo Task Group

    NASA Technical Reports Server (NTRS)

    1964-01-01

    'A technician assigned to the Project Echo Task Group separates the two hemispheres of the Echo 1 container for inspection. The charge that freed the balloon was placed inside of a ring encircling the canister at its equator.' Published in James R. Hansen, Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo, NASA SP-4308, p. 181.

  13. Job Task Analysis.

    ERIC Educational Resources Information Center

    Clemson Univ., SC.

    This publication consists of job task analyses for jobs in textile manufacturing. Information provided for each job in the greige and finishing plants includes job title, job purpose, and job duties with related educational objectives, curriculum, assessment, and outcome. These job titles are included: yarn manufacturing head overhauler, yarn…

  14. Data Center Tasking.

    ERIC Educational Resources Information Center

    Temares, M. Lewis; Lutheran, Joseph A.

    Operations tasking for data center management is discussed. The original and revised organizational structures of the data center at the University of Miami are also described. The organizational strategy addresses the functions that should be performed by the data center, anticipates the specialized skills required, and addresses personnel…

  15. Planetary image conversion task

    NASA Technical Reports Server (NTRS)

    Martin, M. D.; Stanley, C. L.; Laughlin, G.

    1985-01-01

    The Planetary Image Conversion Task group processed 12,500 magnetic tapes containing raw imaging data from JPL planetary missions and produced an image data base in consistent format on 1200 fully packed 6250-bpi tapes. The output tapes will remain at JPL. A copy of the entire tape set was delivered to US Geological Survey, Flagstaff, Ariz. A secondary task converted computer datalogs, which had been stored in project specific MARK IV File Management System data types and structures, to flat-file, text format that is processable on any modern computer system. The conversion processing took place at JPL's Image Processing Laboratory on an IBM 370-158 with existing software modified slightly to meet the needs of the conversion task. More than 99% of the original digital image data was successfully recovered by the conversion task. However, processing data tapes recorded before 1975 was destructive. This discovery is of critical importance to facilities responsible for maintaining digital archives since normal periodic random sampling techniques would be unlikely to detect this phenomenon, and entire data sets could be wiped out in the act of generating seemingly positive sampling results. Reccomended follow-on activities are also included.

  16. Task 1 quarternary tectonics

    SciTech Connect

    Bell, J.W.

    1994-12-31

    Activities on the task of quarternary tectonics for the Yucca Mountain Site investigations are described. Technical topics include: A preliminary reveiw of Bare Mountain Trench; A preliminary detailed lineament map of the Southwestern part of the proposed repository; A discussion on the 1994 Double Spring Flat, Nevada earthquake; and evidence for temporal clustering.

  17. Microprocessor multi-task monitor

    SciTech Connect

    Ludemann, C.A.

    1983-01-01

    This paper describes a multi-task monitor program for microprocessors. Although written for the Intel 8085, it incorporates features that would be beneficial for implementation in other microprocessors used in controlling and monitoring experiments and accelerators. The monitor places permanent programs (tasks) arbitrarily located throughout ROM in a priority ordered queue. The programmer is provided with the flexibility to add new tasks or modified versions of existing tasks, without having to comply with previously defined task boundaries or having to reprogram all of ROM. Scheduling of tasks is triggered by timers, outside stimuli (interrupts), or inter-task communications. Context switching time is of the order of tenths of a milllisecond.

  18. Modulation of neurophysiological auditory processing measures by bilateral transcranial direct current stimulation in schizophrenia.

    PubMed

    Dunn, Walter; Rassovsky, Yuri; Wynn, Jonathan K; Wu, Allan D; Iacoboni, Marco; Hellemann, Gerhard; Green, Michael F

    2016-07-01

    This study used bilateral transcranial direct current stimulation (tDCS) to target neural generators of auditory Mismatch Negativity (MMN) and oddball P300 in schizophrenia patients. tDCS was applied to the pre-frontal cortex in a parallel between-group design. There was a significant main effect of stimulation resulting in modulation of MMN amplitude. This effect was mainly driven by a non-significant, but large, effect-size decrease in MMN amplitude with anodal stimulation. This is the first study to demonstrate that tDCS is able to engage and modulate an EEG-based auditory processing measure in schizophrenia.

  19. A Reverse Stroop Task with Mouse Tracking

    PubMed Central

    Yamamoto, Naohide; Incera, Sara; McLennan, Conor T.

    2016-01-01

    In a reverse Stroop task, observers respond to the meaning of a color word irrespective of the color in which the word is printed—for example, the word red may be printed in the congruent color (red), an incongruent color (e.g., blue), or a neutral color (e.g., white). Although reading of color words in this task is often thought to be neither facilitated by congruent print colors nor interfered with incongruent print colors, this interference has been detected by using a response method that does not give any bias in favor of processing of word meanings or processing of print colors. On the other hand, evidence for the presence of facilitation in this task has been scarce, even though this facilitation is theoretically possible. By modifying the task such that participants respond to a stimulus color word by pointing to a corresponding response word on a computer screen with a mouse, the present study investigated the possibility that not only interference but also facilitation would take place in a reverse Stroop task. Importantly, in this study, participants’ responses were dynamically tracked by recording the entire trajectories of the mouse. Arguably, this method provided richer information about participants’ performance than traditional measures such as reaction time and accuracy, allowing for more detailed (and thus potentially more sensitive) investigation of facilitation and interference in the reverse Stroop task. These trajectories showed that the mouse’s approach toward correct response words was significantly delayed by incongruent print colors but not affected by congruent print colors, demonstrating that only interference, not facilitation, was present in the current task. Implications of these findings are discussed within a theoretical framework in which the strength of association between a task and its response method plays a critical role in determining how word meanings and print colors interact in reverse Stroop tasks. PMID:27199881

  20. A Reverse Stroop Task with Mouse Tracking.

    PubMed

    Yamamoto, Naohide; Incera, Sara; McLennan, Conor T

    2016-01-01

    In a reverse Stroop task, observers respond to the meaning of a color word irrespective of the color in which the word is printed-for example, the word red may be printed in the congruent color (red), an incongruent color (e.g., blue), or a neutral color (e.g., white). Although reading of color words in this task is often thought to be neither facilitated by congruent print colors nor interfered with incongruent print colors, this interference has been detected by using a response method that does not give any bias in favor of processing of word meanings or processing of print colors. On the other hand, evidence for the presence of facilitation in this task has been scarce, even though this facilitation is theoretically possible. By modifying the task such that participants respond to a stimulus color word by pointing to a corresponding response word on a computer screen with a mouse, the present study investigated the possibility that not only interference but also facilitation would take place in a reverse Stroop task. Importantly, in this study, participants' responses were dynamically tracked by recording the entire trajectories of the mouse. Arguably, this method provided richer information about participants' performance than traditional measures such as reaction time and accuracy, allowing for more detailed (and thus potentially more sensitive) investigation of facilitation and interference in the reverse Stroop task. These trajectories showed that the mouse's approach toward correct response words was significantly delayed by incongruent print colors but not affected by congruent print colors, demonstrating that only interference, not facilitation, was present in the current task. Implications of these findings are discussed within a theoretical framework in which the strength of association between a task and its response method plays a critical role in determining how word meanings and print colors interact in reverse Stroop tasks. PMID:27199881

  1. A Reverse Stroop Task with Mouse Tracking.

    PubMed

    Yamamoto, Naohide; Incera, Sara; McLennan, Conor T

    2016-01-01

    In a reverse Stroop task, observers respond to the meaning of a color word irrespective of the color in which the word is printed-for example, the word red may be printed in the congruent color (red), an incongruent color (e.g., blue), or a neutral color (e.g., white). Although reading of color words in this task is often thought to be neither facilitated by congruent print colors nor interfered with incongruent print colors, this interference has been detected by using a response method that does not give any bias in favor of processing of word meanings or processing of print colors. On the other hand, evidence for the presence of facilitation in this task has been scarce, even though this facilitation is theoretically possible. By modifying the task such that participants respond to a stimulus color word by pointing to a corresponding response word on a computer screen with a mouse, the present study investigated the possibility that not only interference but also facilitation would take place in a reverse Stroop task. Importantly, in this study, participants' responses were dynamically tracked by recording the entire trajectories of the mouse. Arguably, this method provided richer information about participants' performance than traditional measures such as reaction time and accuracy, allowing for more detailed (and thus potentially more sensitive) investigation of facilitation and interference in the reverse Stroop task. These trajectories showed that the mouse's approach toward correct response words was significantly delayed by incongruent print colors but not affected by congruent print colors, demonstrating that only interference, not facilitation, was present in the current task. Implications of these findings are discussed within a theoretical framework in which the strength of association between a task and its response method plays a critical role in determining how word meanings and print colors interact in reverse Stroop tasks.

  2. Neural processing of fearful and happy facial expressions during emotion-relevant and emotion-irrelevant tasks: A fixation-to-feature approach.

    PubMed

    Neath-Tavares, Karly N; Itier, Roxane J

    2016-09-01

    Research suggests an important role of the eyes and mouth for discriminating facial expressions of emotion. A gaze-contingent procedure was used to test the impact of fixation to facial features on the neural response to fearful, happy and neutral facial expressions in an emotion discrimination (Exp.1) and an oddball detection (Exp.2) task. The N170 was the only eye-sensitive ERP component, and this sensitivity did not vary across facial expressions. In both tasks, compared to neutral faces, responses to happy expressions were seen as early as 100-120ms occipitally, while responses to fearful expressions started around 150ms, on or after the N170, at both occipital and lateral-posterior sites. Analyses of scalp topographies revealed different distributions of these two emotion effects across most of the epoch. Emotion processing interacted with fixation location at different times between tasks. Results suggest a role of both the eyes and mouth in the neural processing of fearful expressions and of the mouth in the processing of happy expressions, before 350ms.

  3. Verbal Self-Instructions in Task Switching: A Compensatory Tool for Action-Control Deficits in Childhood and Old Age?

    ERIC Educational Resources Information Center

    Kray, Jutta; Eber, Jutta; Karbach, Julia

    2008-01-01

    This study examined the influence of verbal self-instructions on age differences in task switching. Task-switching ability, measured as the difference between performance in single-task blocks and in mixed-task blocks in which participants switch between two tasks (mixing costs), increases during childhood and decreases in old age. To measure the…

  4. Task switching in a hierarchical task structure: evidence for the fragility of the task repetition benefit

    NASA Technical Reports Server (NTRS)

    Lien, Mei-Ching; Ruthruff, Eric

    2004-01-01

    This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms. In Experiments 2-5, adjacent task elements were grouped temporally and/or spatially (forming an ensemble) to create a hierarchical task organization. Results indicate that the effect of switching at the ensemble level dominated the effect of switching at the element level. Experiments 6 and 7, using an ensemble of 3 task elements, revealed that the element-level switch cost was virtually absent between ensembles but was large within an ensemble. The authors conclude that the element-level task repetition benefit is fragile and can be eliminated in a hierarchical task organization.

  5. The task force process

    SciTech Connect

    Applegate, J.S.

    1995-01-31

    This paper focuses on the unique aspects of the Fernald Citizens Task Force process that have contributed to a largely successful public participation effort at Fernald. The Fernald Citizens Task Force passed quickly by many procedural issues. Instead, the Task Force concentrated on (a) educating itself about the site, its problems, and possible solutions, and (b) choosing a directed way to approach its mandate: To make recommendations on several {open_quotes}big picture{close_quotes} issues, including future use of the site, cleanup levels, waste disposition, and cleanup priorities. This paper presents the approach used at Fernald for establishing and running a focused site-specific advisory board, the key issues that have been faced, and how these issues were resolved. The success of Fernald in establishing a strong and functioning site-specific advisory board serves as a useful model for other DOE facilities, although the Fernald model is just one of many approaches that can be taken. However, the approach presented here has worked extremely well for Fernald.

  6. Mobile Thread Task Manager

    NASA Technical Reports Server (NTRS)

    Clement, Bradley J.; Estlin, Tara A.; Bornstein, Benjamin J.

    2013-01-01

    The Mobile Thread Task Manager (MTTM) is being applied to parallelizing existing flight software to understand the benefits and to develop new techniques and architectural concepts for adapting software to multicore architectures. It allocates and load-balances tasks for a group of threads that migrate across processors to improve cache performance. In order to balance-load across threads, the MTTM augments a basic map-reduce strategy to draw jobs from a global queue. In a multicore processor, memory may be "homed" to the cache of a specific processor and must be accessed from that processor. The MTTB architecture wraps access to data with thread management to move threads to the home processor for that data so that the computation follows the data in an attempt to avoid L2 cache misses. Cache homing is also handled by a memory manager that translates identifiers to processor IDs where the data will be homed (according to rules defined by the user). The user can also specify the number of threads and processors separately, which is important for tuning performance for different patterns of computation and memory access. MTTM efficiently processes tasks in parallel on a multiprocessor computer. It also provides an interface to make it easier to adapt existing software to a multiprocessor environment.

  7. Self-regulation, engagement, motivation, and performance in a simulated quality control task.

    PubMed

    Schell, Kraig L; Melton, Ellen C; Woodruff, Abbie; Corbin, G Brandon

    2004-06-01

    This study examined how self-regulation and task-related motivation were related to the accuracy of error detection and task engagement in a simulated quality control task that mimicked prescription-checking behavior in a pharmacy. Ninety-one participants completed measures of self-regulation, task engagement, and task-related motivation and then checked 80 simulated scripts with inserted error ratios ranging from 26% to 38%. Motivation and task engagement were assessed at the beginning of the task, the midpoint of the task, and after the task was over. Performance was measured in terms of sensitivity (error detections) and specificity (false alarm responses). Results indicated that motivation was correlated with higher sensitivity, while self-regulation was correlated with lower specificity. Higher mid-task motivation and higher self-regulation were also predictive of greater task engagement at the midpoint of the task only. Results are discussed and future research directions are proposed.

  8. Task-specific effects of reward on task switching.

    PubMed

    Umemoto, Akina; Holroyd, Clay B

    2015-07-01

    Although cognitive control and reinforcement learning have been researched extensively over the last few decades, only recently have studies investigated their interrelationship. An important unanswered question concerns how the control system decides what task to execute and how vigorously to carry out the task once selected. Based on a recent theory of control formulated according to principles of hierarchical reinforcement learning, we asked whether rewards can affect top-down control over task performance at the level of task representation. Participants were rewarded for correctly performing only one of two tasks in a standard task-switching experiment. Reaction times and error rates were lower for the reinforced task compared to the non-reinforced task. Moreover, the switch cost in error rates for the non-reinforced task was significantly larger compared to the reinforced task, especially for trials in which the imperative stimulus afforded different responses for the two tasks, resulting in a "non-paradoxical" asymmetric switch cost. These findings suggest that reinforcement at the task level resulted in greater application of top-down control rather than in stronger stimulus-response pathways for the rewarded task.

  9. Effects of multitasking on operator performance using computational and auditory tasks.

    PubMed

    Fasanya, Bankole K

    2016-09-01

    This study investigated the effects of multiple cognitive tasks on human performance. Twenty-four students at North Carolina A&T State University participated in the study. The primary task was auditory signal change perception and the secondary task was a computational task. Results showed that participants' performance in a single task was statistically significantly different from their performance in combined tasks: (a) algebra problems (algebra problem primary and auditory perception secondary); (b) auditory perception tasks (auditory perception primary and algebra problems secondary); and (c) mean false-alarm score in auditory perception (auditory detection primary and algebra problems secondary). Using signal detection theory (SDT), participants' performance measured in terms of sensitivity was calculated as -0.54 for combined tasks (algebra problems the primary task) and -0.53 auditory perceptions the primary task. During auditory perception tasks alone, SDT was found to be 2.51. Performance was 83% in a single task compared to 17% when combined tasks.

  10. Task frequency influences stimulus-driven effects on task selection during voluntary task switching.

    PubMed

    Arrington, Catherine M; Reiman, Kaitlin M

    2015-08-01

    Task selection during voluntary task switching involves both top-down (goal-directed) and bottom-up (stimulus-driven) mechanisms. The factors that shift the balance between these two mechanisms are not well characterized. In the present research, we studied the role that task frequency plays in determining the extent of stimulus-driven task selection. In two experiments, we used the basic paradigm adapted from Arrington (Memory & Cognition, 38, 991-997, 2008), in which the effect of stimulus availability serves as a marker of stimulus-driven task selection. A number and letter appeared on each trial with varying stimulus onset asynchronies, and participants performed either a consonant/vowel or an even/odd judgment. In Experiment 1, participants were instructed as to the relative frequency with which each task was to be performed (i.e., 50/50, 60/40, or 75/25) and were further instructed to make their transitions between tasks unpredictable. In Experiment 2, participants were given no instructions about how to select tasks, resulting in naturally occurring variation in task frequency. With both instructed (Exp. 1) and naturally occurring (Exp. 2) relative task frequencies, the less frequently performed task showed a greater effect of stimulus availability on task selection, suggestive of a larger influence of stimulus-driven mechanisms during task performance for the less frequent task. When goal-directed mechanisms of task choice are engaged less frequently, the relative influence of the stimulus environment increases. PMID:26106057

  11. Learner Mining of Pre-Task and Task Input

    ERIC Educational Resources Information Center

    Boston, Jeremy Scott

    2008-01-01

    The findings reported in this article suggest that learners inevitably "mine" wordings contained in pre-task and task materials when performing tasks, even when the teacher did not explicitly draw learner attention to these features. However, this was found to be true only with written materials, and learners did not appear to mine specific…

  12. Maximally Expressive Task Modeling

    NASA Technical Reports Server (NTRS)

    Japp, John; Davis, Elizabeth; Maxwell, Theresa G. (Technical Monitor)

    2002-01-01

    Planning and scheduling systems organize "tasks" into a timeline or schedule. The tasks are defined within the scheduling system in logical containers called models. The dictionary might define a model of this type as "a system of things and relations satisfying a set of rules that, when applied to the things and relations, produce certainty about the tasks that are being modeled." One challenging domain for a planning and scheduling system is the operation of on-board experiment activities for the Space Station. The equipment used in these experiments is some of the most complex hardware ever developed by mankind, the information sought by these experiments is at the cutting edge of scientific endeavor, and the procedures for executing the experiments are intricate and exacting. Scheduling is made more difficult by a scarcity of space station resources. The models to be fed into the scheduler must describe both the complexity of the experiments and procedures (to ensure a valid schedule) and the flexibilities of the procedures and the equipment (to effectively utilize available resources). Clearly, scheduling space station experiment operations calls for a "maximally expressive" modeling schema. Modeling even the simplest of activities cannot be automated; no sensor can be attached to a piece of equipment that can discern how to use that piece of equipment; no camera can quantify how to operate a piece of equipment. Modeling is a human enterprise-both an art and a science. The modeling schema should allow the models to flow from the keyboard of the user as easily as works of literature flowed from the pen of Shakespeare. The Ground Systems Department at the Marshall Space Flight Center has embarked on an effort to develop a new scheduling engine that is highlighted by a maximally expressive modeling schema. This schema, presented in this paper, is a synergy of technological advances and domain-specific innovations.

  13. Silicon material task review

    NASA Technical Reports Server (NTRS)

    Lorenz, J. H.

    1986-01-01

    The objectives of the Flat-plate Solar Array (FSA) Project Silicon Material Task are to evaluate technologies, new and old; to develop the most promising technologies; to establish practicality of the processes to meet production, energy use, and economic criteria; and to develop an information base on impurities in polysilicon and to determine their effects on solar cell performance. The approach involves determining process feasibility, setting milestones for the forced selection of the processes, and establishing the technical readiness of the integrated process.

  14. Quarternary tectonics, Task 1

    SciTech Connect

    Bell, J.W.

    1993-09-30

    Activities conducted for the evaluation of the geology and seismotectonics stability of Yucca Mountain as a potential site for the underground disposal of high-level radioactive wastes continued. Tasks concerned with quaternary tectonics include: scheduling of photography of Little Skull Mountain area; the collection and dating of rock varnish samples from the 1932 Cedar Mountain earthquake area for carbon 14 AMS and cation-ratio analysis; collection of samples for thermoluminescence dating from the 1932 Cedar Mountain earthquake area; mapping of the northern area of Crater Flat; and surveying of the May 17, 1993 Eureka the Valley earthquake area.

  15. An auditory display in a dual-axis tracking task.

    NASA Technical Reports Server (NTRS)

    Mirchandani, P. B.

    1972-01-01

    Results of a study in which subjects were presented concurrently with the primary task of controlling a second-order plant and the secondary task of controlling a first-order plant. The plant errors for the two tasks were shown on separate visual displays. An auditory display, whose output varied in frequency and volume with the error, was used to supplement the secondary task in half of the runs. To study the effects of the auditory display, two performance measures were obtained: (1) the integral of the squared error (ISE) and (2) the describing functions of the human operator. Statistical analysis of the ISE measures indicated that when the secondary task was supplemented with an auditory display, there was a significant improvement in performance on the secondary task. The performance on the primary task improved on the average, but not significantly. The variances of the ISE values decreased for both the tasks, indicating a more consistent behavior with the auditory display. The describing function analysis showed that supplementing the secondary task with the auditory display increased the low frequency gain of the human operator for this task. The describing functions for the primary task did not show any apparent changes.

  16. An empirical study of task switching locality in MVS

    SciTech Connect

    Kobayashi, M.

    1986-08-01

    The ''hit ratio'' of a high-speed buffer (cache) depends on the ''locality'' of memory references. However, locality of reference is disturbed and the hit ratio decreases whenever a task switch occurs. This performance degradation can be minimized if ''locality of task switching,'' the tendency for a small set of favored tasks to be frequently executed, exists and the cache is organized in such a way that it can hold blocks (lines) of multiple tasks. Locality of task switching and locality of memory references in individual tasks exhibit overall locality of memory references at a system level. This paper addresses the following questions. Does locality of task switching really exist. How can it be modeled. Task switching in IBM operating system/virtual storage with multiple virtual storage (OS/VS2 MVS) was measured using event traces for three different workloads to show that locality of task switching actually exists in MVS. Two different models of task switching are proposed. These models can be incorporated into cache multitasking models to predict more accurately the misses in real computer systems. A key parameter of the models is the task execution interval; measurements of execution intervals for the workloads used in the paper are presented and discussed.

  17. Manipulator Performance Evaluation Using Fitts' Taping Task

    SciTech Connect

    Draper, J.V.; Jared, B.C.; Noakes, M.W.

    1999-04-25

    Metaphorically, a teleoperator with master controllers projects the user's arms and hands into a re- mote area, Therefore, human users interact with teleoperators at a more fundamental level than they do with most human-machine systems. Instead of inputting decisions about how the system should func- tion, teleoperator users input the movements they might make if they were truly in the remote area and the remote machine must recreate their trajectories and impedance. This intense human-machine inter- action requires displays and controls more carefully attuned to human motor capabilities than is neces- sary with most systems. It is important for teleoperated manipulators to be able to recreate human trajectories and impedance in real time. One method for assessing manipulator performance is to observe how well a system be- haves while a human user completes human dexterity tasks with it. Fitts' tapping task has been, used many times in the past for this purpose. This report describes such a performance assessment. The International Submarine Engineering (ISE) Autonomous/Teleoperated Operations Manipulator (ATOM) servomanipulator system was evalu- ated using a generic positioning accuracy task. The task is a simple one but has the merits of (1) pro- ducing a performance function estimate rather than a point estimate and (2) being widely used in the past for human and servomanipulator dexterity tests. Results of testing using this task may, therefore, allow comparison with other manipulators, and is generically representative of a broad class of tasks. Results of the testing indicate that the ATOM manipulator is capable of performing the task. Force reflection had a negative impact on task efficiency in these data. This was most likely caused by the high resistance to movement the master controller exhibited with the force reflection engaged. Measurements of exerted forces were not made, so it is not possible to say whether the force reflection helped partici- pants

  18. Atomic Oxygen Task

    NASA Technical Reports Server (NTRS)

    Hadaway, James B.

    1997-01-01

    This report details work performed by the Center for Applied Optics (CAO) at the University of Alabama in Huntsville (UAH) on the contract entitled 'Atomic Oxygen Task' for NASA's Marshall Space Flight Center (contract NAS8-38609, Delivery Order 109, modification number 1). Atomic oxygen effects on exposed materials remain a critical concern in designing spacecraft to withstand exposure in the Low Earth Orbit (LEO) environment. The basic objective of atomic oxygen research in NASA's Materials & Processes (M&P) Laboratory is to provide the solutions to material problems facing present and future space missions. The objective of this work was to provide the necessary research for the design of specialized experimental test configurations and development of techniques for evaluating in-situ space environmental effects, including the effects of atomic oxygen and electromagnetic radiation on candidate materials. Specific tasks were performed to address materials issues concerning accelerated environmental testing as well as specifically addressing materials issues of particular concern for LDEF analysis and Space Station materials selection.

  19. Inhibition in Dot Comparison Tasks

    ERIC Educational Resources Information Center

    Clayton, Sarah; Gilmore, Camilla

    2015-01-01

    Dot comparison tasks are commonly used to index an individual's Approximate Number System (ANS) acuity, but the cognitive processes involved in completing these tasks are poorly understood. Here, we investigated how factors including numerosity ratio, set size and visual cues influence task performance. Forty-four children aged 7-9 years completed…

  20. Task Analysis: A Proactive Paradigm.

    ERIC Educational Resources Information Center

    Cipriano, Robert E.

    A sequential and developmental curriculum design is conceptualized, based on task analysis. Task analysis is a detailed inquiry into actions undertaken in performing specific tasks or jobs. Baseline data form a database on which education and training programs are designed, produced, and evaluated. The following are sources of information for task…

  1. Skill Components of Task Analysis

    ERIC Educational Resources Information Center

    Adams, Anne E.; Rogers, Wendy A.; Fisk, Arthur D.

    2013-01-01

    Some task analysis methods break down a task into a hierarchy of subgoals. Although an important tool of many fields of study, learning to create such a hierarchy (redescription) is not trivial. To further the understanding of what makes task analysis a skill, the present research examined novices' problems with learning Hierarchical Task…

  2. Task-Based Information Searching.

    ERIC Educational Resources Information Center

    Vakkari, Pertti

    2003-01-01

    Reviews studies on the relationship between task performance and information searching by end-users, focusing on information searching in electronic environments and information retrieval systems. Topics include task analysis; task characteristics; search goals; modeling information searching; modeling search goals; information seeking behavior;…

  3. TASK: Let's Have a Party!

    ERIC Educational Resources Information Center

    Rees, James

    2012-01-01

    In this article, the author describes a creative way to demystify contemporary art for students. TASK is artist Oliver Herring's creation, where participants actively interpret instructions found on little pieces of paper--what he calls "tasks." An art classroom has all the key ingredients for a TASK event: (1) people; (2) materials; (3) space;…

  4. Principles of Communicative Task Design.

    ERIC Educational Resources Information Center

    Nunan, David

    The use of the learning task as a basic planning and instructional tool for communicative second language instruction is discussed, and considerations and procedures for designing such tasks are outlined. A task is defined as a piece of classroom work that involves learners in comprehending, manipulating, producing, or interacting in the target…

  5. Word Fluency: A Task Analysis.

    ERIC Educational Resources Information Center

    Laine, Matti

    It is suggested that models of human problem solving are useful in the analysis of word fluency (WF) test performance. In problem-solving terms, WF tasks would require the subject to define and clarify the conditions of the task (task acquisition), select and employ appropriate strategies, and monitor one's performance. In modern neuropsychology,…

  6. 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…

  7. Component Processes in Task Switching.

    ERIC Educational Resources Information Center

    Meiran, Nachshon; Chorev, Ziv; Sapir, Ayelet

    2000-01-01

    Studied task switching in 4 experiments involving 111 Israeli undergraduates. Results show the preparation for a task switch is not a by-product of general preparation by phasic alertness or predicting target onset and establish reconfiguration as a separate preparatory process. Suggests that there are at least three components of task switching…

  8. Elementary derivative tasks and neural net multiscale analysis of tasks.

    PubMed

    Giraud, B G; Touzeau, A

    2002-01-01

    Formal neurons implementing wavelets have been shown to build nets that are able to approximate any multidimensional task. In this paper, we use a finite number of formal neurons implementing elementary tasks such as "sombrero" responses or even simpler "window" responses, with adjustable widths. We show this to provide a reasonably efficient, practical and robust, multifrequency analysis of tasks. The translation degree of freedom of wavelets is shown to be unnecessary. A training algorithm, optimizing the output task with respect to the widths of the responses, reveals two distinct training modes. The first mode keeps the formal neurons distinct. The other mode induces some of the formal neurons to become identical, with output weights of equal strengths but opposite signs. Hence this latter mode promotes tasks that are derivatives of the elementary tasks with respect to the width parameter. Such results, obtained from optimizations with respect to a width parameter, can be generalized for any other parameters of the elementary tasks.

  9. The Process of Designing Task Features

    ERIC Educational Resources Information Center

    Bauer, Malcolm

    2014-01-01

    Malcolm Bauer, from Education Testing Services, provides his comments on the Focus article in this issue of "Measurement" entitled : "How Task Features Impact Evidence from Assessments Embedded in Simulations and Games" (Russell G. Almond, Yoon Jeon Kim, Gertrudes Velasquez, Valerie J. Shute). Bauer begins his remarks by noting…

  10. Using Performance Task Data to Improve Instruction

    ERIC Educational Resources Information Center

    Abbott, Amy L.; Wren, Douglas G.

    2016-01-01

    Two well-accepted ideas among educators are (a) performance assessment is an effective means of assessing higher-order thinking skills and (b) data-driven instruction planning is a valuable tool for optimizing student learning. This article describes a locally developed performance task (LDPT) designed to measure critical thinking, problem…

  11. Task Speed and Accuracy Decrease When Multitasking

    ERIC Educational Resources Information Center

    Lin, Lin; Cockerham, Deborah; Chang, Zhengsi; Natividad, Gloria

    2016-01-01

    As new technologies increase the opportunities for multitasking, the need to understand human capacities for multitasking continues to grow stronger. Is multitasking helping us to be more efficient? This study investigated the multitasking abilities of 168 participants, ages 6-72, by measuring their task accuracy and completion time when they…

  12. Sleep Deprivation and Time-on-Task Performance Decrement in the Rat Psychomotor Vigilance Task

    PubMed Central

    Oonk, Marcella; Davis, Christopher J.; Krueger, James M.; Wisor, Jonathan P.; Van Dongen, Hans P.A.

    2015-01-01

    Study Objectives: The rat psychomotor vigilance task (rPVT) was developed as a rodent analog of the human psychomotor vigilance task (hPVT). We examined whether rPVT performance displays time-on-task effects similar to those observed on the hPVT. Design: The rPVT requires rats to respond to a randomly presented light stimulus to obtain a water reward. Rats were water deprived for 22 h prior to each 30-min rPVT session to motivate performance. We analyzed rPVT performance over time on task and as a function of the response-stimulus interval, at baseline and after sleep deprivation. Setting: The study was conducted in an academic research vivarium. Participants: Male Long-Evans rats were trained to respond to a 0.5 sec stimulus light within 3 sec of stimulus onset. Complete data were available for n = 20 rats. Interventions: Rats performed the rPVT for 30 min at baseline and after 24 h total sleep deprivation by gentle handling. Measurements and Results: Compared to baseline, sleep deprived rats displayed increased performance lapses and premature responses, similar to hPVT lapses of attention and false starts. However, in contrast to hPVT performance, the time-on-task performance decrement was not significantly enhanced by sleep deprivation. Moreover, following sleep deprivation, rPVT response times were not consistently increased after short response-stimulus intervals. Conclusions: The rat psychomotor vigilance task manifests similarities to the human psychomotor vigilance task in global performance outcomes, but not in post-sleep deprivation effects of time on task and response-stimulus interval. Citation: Oonk M, Davis CJ, Krueger JM, Wisor JP, Van Dongen HPA. Sleep deprivation and time-on-task performance decrement in the rat psychomotor vigilance task. SLEEP 2015;38(3):445–451. PMID:25515099

  13. The binocular advantage in visuomotor tasks involving tools.

    PubMed

    Read, Jenny C A; Begum, Shah Farzana; McDonald, Alice; Trowbridge, Jack

    2013-01-01

    We compared performance on three manual-dexterity tasks under monocular and binocular viewing. The tasks were the standard Morrisby Fine Dexterity Test, using forceps to manipulate the items, a modified version of the Morrisby test using fingers, and a "buzz-wire" task in which subjects had to guide a wire hoop around a 3D track without bringing the hoop into contact with the track. In all three tasks, performance was better for binocular viewing. The extent of the binocular advantage in individuals did not correlate significantly with their stereoacuity measured on the Randot test. However, the extent of the binocular advantage depended strongly on the task. It was weak when fingers were used on the Morrisby task, stronger with forceps, and extremely strong on the buzz-wire task (fivefold increase in error rate with monocular viewing). We suggest that the 3D buzz-wire game is particularly suitable for assessing binocularly based dexterity.

  14. Task Analysis Technologies at KSC

    NASA Technical Reports Server (NTRS)

    Carstens, Deborah S.

    2003-01-01

    Project objective: (1) Form an integrated team of NASA. USA, Boeing, and Dynacs researches. (2) Create a user friendly software prototype that assists an analyst in performing a human factors process failure modes and effects analysis (HF-PFMEA). (3)Perform four task analyses on center: cargo late access task analysis (NASA/Boeing team); payload test and verification system task analysis (NASA/Boeing team); slammer cover installation operations task analysis (NASA/USA team); ATDC LOX pump acceptance test procedure task analysis (NASA/Dynacs team).

  15. Task directed sensing

    NASA Technical Reports Server (NTRS)

    Firby, R. James

    1990-01-01

    High-level robot control research must confront the limitations imposed by real sensors if robots are to be controlled effectively in the real world. In particular, sensor limitations make it impossible to maintain a complete, detailed world model of the situation surrounding the robot. To address the problems involved in planning with the resulting incomplete and uncertain world models, traditional robot control architectures must be altered significantly. Task-directed sensing and control is suggested as a way of coping with world model limitations by focusing sensing and analysis resources on only those parts of the world relevant to the robot's active goals. The RAP adaptive execution system is used as an example of a control architecture designed to deploy sensing resources in this way to accomplish both action and knowledge goals.

  16. The Effect of Hierarchical Task Representations on Task Selection in Voluntary Task Switching

    ERIC Educational Resources Information Center

    Weaver, Starla M.; Arrington, Catherine M.

    2013-01-01

    The current study explored the potential for hierarchical representations to influence action selection during voluntary task switching. Participants switched between 4 individual task elements. In Experiment 1, participants were encouraged to represent the task elements as grouped within a hierarchy based on experimental manipulations of varying…

  17. AMU NEXRAD Exploitation Task

    NASA Technical Reports Server (NTRS)

    Lambert, Winifred C.; Wheeler, Mark M.

    1997-01-01

    This report documents the results of the Applied Meteorology Unit's NEXRAD Exploitation Task. The objectives of this task are to determine what radar signatures are present prior to and at the time of convection initiation, and to determine radar signatures which will help distinguish whether the ensuing convection will become severe. Radar data from the WSR-88D radar located at NWS Melbourne (WSR-88D/KMLB) were collected between June and September 1995, and 16 convective case studies were analyzed for which the radar was operating during the entire period of interest. All WSR-88D/KMLB products were scrutinized for their utility in detecting convection initiation and severe storm signatures. Through process of elimination, it was found that the 0.5 deg reflectivity product with the lowest reflectivity values displayed is the best product to monitor for convection initiation signatures. Seven meteorological features associated with the initiation of deep convection were identified: the Merritt Island and Indian River convergence zones, interlake convergence, horizontal convective rolls, the sea breeze, storm outflow boundaries, and fires. Their reflectivity values ranged from -5 to 20 dBZ. Of the three severe weather phenomena (winds greater than or equal to 50 kts, tornado, 3/4 inch hail), high wind events due to microbursts were most common in the data set. It was found that the values and trends of composite reflectivity, vertically integrated liquid, and core aspect ratio were key indicators of the potential of a cell to produce a microburst. The data were not analyzed for the other two severe weather phenomena because they rarely occurred during the data collection period. This report also includes suggestions for new WSR-88D products, summaries of ongoing research aimed at creating new products, and explicit recommended procedures for detecting convection initiation and severe storm signatures in the radar data using the currently available technology.

  18. Task simulation in computer-based training

    SciTech Connect

    Gardner, P.R.

    1988-02-01

    Westinghouse Hanford Company (WHC) makes extensive use of job-task simulations in company-developed computer-based training (CBT) courseware. This courseware is different from most others because it does not simulate process control machinery or other computer programs, instead the WHC Excerises model day-to-day tasks such as physical work preparations, progress, and incident handling. These Exercises provide a higher level of motivation and enable the testing of more complex patterns of behavior than those typically measured by multiple-choice and short questions. Examples from the WHC Radiation Safety and Crane Safety courses will be used as illustrations. 3 refs.

  19. Shaping academic task engagement with percentile schedules.

    PubMed

    Athens, Elizabeth S; Vollmer, Timothy R; Pipkin, Claire C St Peter

    2007-01-01

    The purpose of this study was to examine the use of percentile schedules as a method of quantifying the shaping procedure in an educational setting. We compared duration of task engagement during baseline measurements for 4 students to duration of task engagement during a percentile schedule. As a secondary purpose, we examined the influence on shaping of manipulations of the number of observations used to determine the criterion for reinforcement (the m parameter of the percentile formula). Results showed that the percentile formula was most effective when a relatively large m value (20 observations) was used.

  20. Electroencephalographic monitoring of complex mental tasks

    NASA Technical Reports Server (NTRS)

    Guisado, Raul; Montgomery, Richard; Montgomery, Leslie; Hickey, Chris

    1992-01-01

    Outlined here is the development of neurophysiological procedures to monitor operators during the performance of cognitive tasks. Our approach included the use of electroencepalographic (EEG) and rheoencephalographic (REG) techniques to determine changes in cortical function associated with cognition in the operator's state. A two channel tetrapolar REG, a single channel forearm impedance plethysmograph, a Lead I electrocardiogram (ECG) and a 21 channel EEG were used to measure subject responses to various visual-motor cognitive tasks. Testing, analytical, and display procedures for EEG and REG monitoring were developed that extend the state of the art and provide a valuable tool for the study of cerebral circulatory and neural activity during cognition.

  1. Shaping Academic Task Engagement with Percentile Schedules

    PubMed Central

    Athens, Elizabeth S; Vollmer, Timothy R; St. Peter Pipkin, Claire C

    2007-01-01

    The purpose of this study was to examine the use of percentile schedules as a method of quantifying the shaping procedure in an educational setting. We compared duration of task engagement during baseline measurements for 4 students to duration of task engagement during a percentile schedule. As a secondary purpose, we examined the influence on shaping of manipulations of the number of observations used to determine the criterion for reinforcement (the m parameter of the percentile formula). Results showed that the percentile formula was most effective when a relatively large m value (20 observations) was used. PMID:17970261

  2. Frequency Analysis Of Data On Telerobotic Tasks

    NASA Technical Reports Server (NTRS)

    Fiorini, Paolo; Giancaspro, Antonio

    1994-01-01

    Data on forces and torques measured in experiments with remote manipulators processed into spectral signatures via special frequency-analysis procedure. Spectral signatures complement other measures used to evaluate performances of telerobotic systems and human operators. Contributes to verification of some assumptions made in designing manipulator arms and control subsystems and used as feedback by operators engaged in realtime monitoring of telerobotic tasks. Also provides useful indications of flows of power between manipulators and their environments.

  3. Modeling one-choice and two-choice driving tasks

    PubMed Central

    Ratcliff, Roger

    2015-01-01

    An experiment is presented in which subjects were tested on both one-choice and two-choice driving tasks and on non-driving versions of them. Diffusion models for one- and two-choice tasks were successful in extracting model-based measures from the response time and accuracy data. These include measures of the quality of the information from the stimuli that drove the decision process (drift rate in the model), the time taken up by processes outside the decision process and, for the two-choice model, the speed/accuracy decision criteria that subjects set. Drift rates were only marginally different between the driving and non-driving tasks, indicating that nearly the same information was used in the two kinds of tasks. The tasks differed in the time taken up by other processes, reflecting the difference between them in response processing demands. Drift rates were significantly correlated across the two two-choice tasks showing that subjects that performed well on one task also performed well on the other task. Nondecision times were correlated across the two driving tasks, showing common abilities on motor processes across the two tasks. These results show the feasibility of using diffusion modeling to examine decision making in driving and so provide for a theoretical examination of factors that might impair driving, such as extreme aging, distraction, sleep deprivation, and so on. PMID:25944448

  4. Using teacher greetings to increase speed to task engagement.

    PubMed

    Allday, R Allan; Bush, Miranda; Ticknor, Nicole; Walker, Lindsay

    2011-01-01

    We used a multiple baseline design across participants to determine if teacher greetings would reduce the latency to task engagement. Three participants were identified by their respective teachers as having difficulty initiating task-appropriate engagement at the beginning of class. Latency was measured from teacher greeting until the participant was actively engaged for 5 consecutive seconds. Results showed that teacher greetings were effective at reducing latency to task engagement for all participants.

  5. [Guidelines for redesigning jobs with repetitive tasks].

    PubMed

    Colombini, D; Occhipinti, E; Meroni, M; Menoni, O; Bergamasco, R; Girola, C; Grea, V; Vendola, D

    1996-01-01

    Preventive measures aimed at minimising the occurrence of work-related musculo-skeletal disorders of the upper limbs (WMSDs) associated with repetitive tasks can be divided into 3 categories: structural, organisational and educational. Whenever specific risk and injury assessments have shown the need for preventive action, this is most often implemented within the framework of a range of assorted measures. In particular, structural measures pertain to optimising the layout of the work area and furnishings, and the "ergonomic" properties of work tools and equipment. Such measures serve to alleviate the problems caused by the use of excessive force and improper postures. The authors refer to the principles guiding such structural measures, in the light of the extensive literature that has been published on the subject. Organisational (or re-organisational) measures essentially relate to job design (i.e. distribution of tasks, speeds and pauses). They serve to alleviate problems connected with highly repetitive and frequent actions, excessively lengthy tasks and inadequate recovery periods. Very few relevant findings are available: the authors therefore illustrate in some detail a practical trial conducted in a major engineering firm. The objective was to lower to acceptable limits the frequency of certain repetitive tasks performed by workers using their upper limbs. The trial made it possible to identify a suitable plan and schedule of measures taking into due consideration the impact of the plan on production levels (and costs). The fundamental principles guiding the adoption of specific educational and training programmes for the workers and their supervisors are presented and discussed.

  6. Functional Task Test: 2. Spaceflight-Induced Cardiovascular Change and Recovery During NASA's Functional Task Test

    NASA Technical Reports Server (NTRS)

    Phillips, Tiffany; Arzeno, Natalia M.; Stenger, Michael; Lee, Stuart M. C.; Bloomberg, Jacob J.; Platts, Steven H.

    2011-01-01

    The overall objective of the functional task test (FTT) is to correlate spaceflight-induced physiological adaptations with changes in performance of high priority exploration mission-critical tasks. This presentation will focus on the recovery from fall/stand test (RFST), which measures the cardiovascular response to the transition from the prone posture (simulated fall) to standing in normal gravity, as well as heart rate (HR) during 11 functional tasks. As such, this test describes some aspects of spaceflight-induced cardiovascular deconditioning and the course of recovery in Space Shuttle and International Space Station (ISS) astronauts. The sensorimotor and neuromuscular components of the FTT are described in two separate abstracts: Functional Task Test 1 and 3.

  7. The minimum entropy principle and task performance.

    PubMed

    Guastello, Stephen J; Gorin, Hillary; Huschen, Samuel; Peters, Natalie E; Fabisch, Megan; Poston, Kirsten; Weinberger, Kelsey

    2013-07-01

    According to the minimum entropy principle, efficient cognitive performance is produced with a neurocognitive strategy that involves a minimum of degrees of freedom. Although high performance is often regarded as consistent performance as well, some variability in performance still remains which allows the person to adapt to changing goal conditions or fatigue. The present study investigated the connection between performance, entropy in performance, and four task-switching strategies. Fifty-one undergraduates performed 7 different computer-based cognitive tasks producing sets of 49 responses under instructional conditions requiring task quotas or no quotas. The temporal patterns of performance were analyzed using orbital decomposition to extract pattern types and lengths, which were then compared with regard to Shannon entropy, topological entropy, and overall performance. Task switching strategies from a previous study were available for the same participants as well. Results indicated that both topological entropy and Shannon entropy were negatively correlated with performance. Some task-switching strategies produced lower entropy in performance than others. Stepwise regression showed that the top three predictors of performance were Shannon entropy and arithmetic and spatial abilities. Additional implications for the prediction of work performance with cognitive ability measurements and the applicability of the minimum entropy principle to multidimensional performance criteria and team work are discussed.

  8. [Performance indicators: the role of 'task uncertainty'].

    PubMed

    van Dishoeck, Anne-Margreet; Lingsma, Hester F; Steyerberg, Ewout W

    2010-01-01

    In recent years, quality of care has occupied a prominent place in health care. Different performance indicators are used to assess the quality of care. There is some debate about the value of outcome versus process indicators in measuring aspects of quality of care. Van de Geer et al. carried out a field study in a medical rehabilitation centre in the Netherlands in which four low task uncertainty teams ('hand trauma', 'heart failure', 'amputation', 'chronic pain'), and four high task uncertainty teams ('children with developmental coordination disorder', 'Parkinson disease', 'young children (aged 1-4 years) with developmental disorders', 'acquired brain injuries') participated in the development of performance indicators. They concluded that task uncertainty is an important factor to be considered in the development of indicators, and in the choice between the use of process and outcome indicators. Notably, outcome indicators are only useful in health problems with little variation and little task uncertainty, while many tasks are complex and uncertain. The participation of health care professionals in the development of quality indicators is, therefore, very important.

  9. Measuring $\

    SciTech Connect

    Mitchell, Jessica Sarah

    2011-01-01

    The MINOS Experiment consists of two steel-scintillator calorimeters, sampling the long baseline NuMI muon neutrino beam. It was designed to make a precise measurement of the ‘atmospheric’ neutrino mixing parameters, Δm2 atm. and sin2 (2 atm.). The Near Detector measures the initial spectrum of the neutrino beam 1km from the production target, and the Far Detector, at a distance of 735 km, measures the impact of oscillations in the neutrino energy spectrum. Work performed to validate the quality of the data collected by the Near Detector is presented as part of this thesis. This thesis primarily details the results of a vμ disappearance analysis, and presents a new sophisticated fitting software framework, which employs a maximum likelihood method to extract the best fit oscillation parameters. The software is entirely decoupled from the extrapolation procedure between the detectors, and is capable of fitting multiple event samples (defined by the selections applied) in parallel, and any combination of energy dependent and independent sources of systematic error. Two techniques to improve the sensitivity of the oscillation measurement were also developed. The inclusion of information on the energy resolution of the neutrino events results in a significant improvement in the allowed region for the oscillation parameters. The degree to which sin2 (2θ )= 1.0 could be disfavoured with the exposure of the current dataset if the true mixing angle was non-maximal, was also investigated, with an improved neutrino energy reconstruction for very low energy events. The best fit oscillation parameters, obtained by the fitting software and incorporating resolution information were: | Δm2| = 2.32+0.12 -0.08×10-3 eV2 and sin2 (2θ ) > 0.90(90% C.L.). The analysis provides the current world best measurement of the atmospheric neutrino mass

  10. Measuring Resilience.

    ERIC Educational Resources Information Center

    O'Neal, Marcia R.

    Locating and selecting an instrument that measures resilience is no simple task. This document provides information about several measures of resilience or hardiness that have been used in recent years. The discussion of each measure includes information about its origins, a description of the measure and its uses, and a discussion of the…

  11. Proposing Metrics for Benchmarking Novel EEG Technologies Towards Real-World Measurements

    PubMed Central

    Oliveira, Anderson S.; Schlink, Bryan R.; Hairston, W. David; König, Peter; Ferris, Daniel P.

    2016-01-01

    Recent advances in electroencephalographic (EEG) acquisition allow for recordings using wet and dry sensors during whole-body motion. The large variety of commercially available EEG systems contrasts with the lack of established methods for objectively describing their performance during whole-body motion. Therefore, the aim of this study was to introduce methods for benchmarking the suitability of new EEG technologies for that context. Subjects performed an auditory oddball task using three different EEG systems (Biosemi wet—BSM, Cognionics Wet—Cwet, Conionics Dry—Cdry). Nine subjects performed the oddball task while seated and walking on a treadmill. We calculated EEG epoch rejection rate, pre-stimulus noise (PSN), signal-to-noise ratio (SNR) and EEG amplitude variance across the P300 event window (CVERP) from a subset of 12 channels common to all systems. We also calculated test-retest reliability and the subject’s level of comfort while using each system. Our results showed that using the traditional 75 μV rejection threshold BSM and Cwet epoch rejection rates are ~25% and ~47% in the seated and walking conditions respectively. However, this threshold rejects ~63% of epochs for Cdry in the seated condition and excludes 100% of epochs for the majority of subjects during walking. BSM showed predominantly no statistical differences between seated and walking condition for all metrics, whereas Cwet showed increases in PSN and CVERP, as well as reduced SNR in the walking condition. Data quality from Cdry in seated conditions were predominantly inferior in comparison to the wet systems. Test-retest reliability was mostly moderate/good for these variables, especially in seated conditions. In addition, subjects felt less discomfort and were motivated for longer recording periods while using wet EEG systems in comparison to the dry system. The proposed method was successful in identifying differences across systems that are mostly caused by motion

  12. Hypercube matrix computation task

    NASA Technical Reports Server (NTRS)

    Calalo, Ruel H.; Imbriale, William A.; Jacobi, Nathan; Liewer, Paulett C.; Lockhart, Thomas G.; Lyzenga, Gregory A.; Lyons, James R.; Manshadi, Farzin; Patterson, Jean E.

    1988-01-01

    A major objective of the Hypercube Matrix Computation effort at the Jet Propulsion Laboratory (JPL) is to investigate the applicability of a parallel computing architecture to the solution of large-scale electromagnetic scattering problems. Three scattering analysis codes are being implemented and assessed on a JPL/California Institute of Technology (Caltech) Mark 3 Hypercube. The codes, which utilize different underlying algorithms, give a means of evaluating the general applicability of this parallel architecture. The three analysis codes being implemented are a frequency domain method of moments code, a time domain finite difference code, and a frequency domain finite elements code. These analysis capabilities are being integrated into an electromagnetics interactive analysis workstation which can serve as a design tool for the construction of antennas and other radiating or scattering structures. The first two years of work on the Hypercube Matrix Computation effort is summarized. It includes both new developments and results as well as work previously reported in the Hypercube Matrix Computation Task: Final Report for 1986 to 1987 (JPL Publication 87-18).

  13. Mind wandering in text comprehension under dual-task conditions

    PubMed Central

    Dixon, Peter; Li, Henry

    2013-01-01

    In two experiments, subjects responded to on-task probes while reading under dual-task conditions. The secondary task was to monitor the text for occurrences of the letter e. In Experiment 1, reading comprehension was assessed with a multiple-choice recognition test; in Experiment 2, subjects recalled the text. In both experiments, the secondary task replicated the well-known “missing-letter effect” in which detection of e's was less effective for function words and the word “the.” Letter detection was also more effective when subjects were on task, but this effect did not interact with the missing-letter effect. Comprehension was assessed in both the dual-task conditions and in control single-task conditions. In the single-task conditions, both recognition (Experiment 1) and recall (Experiment 2) was better when subjects were on task, replicating previous research on mind wandering. Surprisingly, though, comprehension under dual-task conditions only showed an effect of being on task when measured with recall; there was no effect on recognition performance. Our interpretation of this pattern of results is that subjects generate responses to on-task probes on the basis of a retrospective assessment of the contents of working memory. Further, we argue that under dual-task conditions, the contents of working memory is not closely related to the reading processes required for accurate recognition performance. These conclusions have implications for models of text comprehension and for the interpretation of on-task probe responses. PMID:24101909

  14. Cognitive caching promotes flexibility in task switching: evidence from event-related potentials.

    PubMed

    Lange, Florian; Seer, Caroline; Müller, Dorothea; Kopp, Bruno

    2015-01-01

    Time-consuming processes of task-set reconfiguration have been shown to contribute to the costs of switching between cognitive tasks. We describe and probe a novel mechanism serving to reduce the costs of task-set reconfiguration. We propose that when individuals are uncertain about the currently valid task, one task set is activated for execution while other task sets are maintained at a pre-active state in cognitive cache. We tested this idea by assessing an event-related potential (ERP) index of task-set reconfiguration in a three-rule task-switching paradigm involving varying degrees of task uncertainty. In high-uncertainty conditions, two viable tasks were equally likely to be correct whereas in low-uncertainty conditions, one task was more likely than the other. ERP and performance measures indicated substantial costs of task-set reconfiguration when participants were required to switch away from a task that had been likely to be correct. In contrast, task-set-reconfiguration costs were markedly reduced when the previous task set was chosen under high task uncertainty. These results suggest that cognitive caching of alternative task sets adds to human cognitive flexibility under high task uncertainty. PMID:26643146

  15. Intelligence, but Not Emotional Intelligence, Predicts Iowa Gambling Task Performance

    ERIC Educational Resources Information Center

    Demaree, Heath A.; Burns, Kevin J.; DeDonno, Michael A.

    2010-01-01

    The Iowa Gambling Task (IGT) is a famous and frequently-used neuropsychological task that is thought to reflect real-world decision-making. There has been some debate, however, about the degree to which the IGT involves cold (cognitive) versus hot (emotional) processing. The present study incorporated 68 healthy individuals and used measures of…

  16. Control of Task Sequences: What Is the Role of Language?

    ERIC Educational Resources Information Center

    Mayr, Ulrich; Kleffner-Canucci, Killian; Kikumoto, Atsushi; Redford, Melissa A.

    2014-01-01

    It is almost a truism that language aids serial-order control through self-cuing of upcoming sequential elements. We measured speech onset latencies as subjects performed hierarchically organized task sequences while "thinking aloud" each task label. Surprisingly, speech onset latencies and response times (RTs) were highly synchronized,…

  17. Continuous Performance Tasks: Not Just about Sustaining Attention

    ERIC Educational Resources Information Center

    Roebuck, Hettie; Freigang, Claudia; Barry, Johanna G.

    2016-01-01

    Purpose: Continuous performance tasks (CPTs) are used to measure individual differences in sustained attention. Many different stimuli have been used as response targets without consideration of their impact on task performance. Here, we compared CPT performance in typically developing adults and children to assess the role of stimulus processing…

  18. Initial development of an automated task analysis profiling system

    SciTech Connect

    Jorgensen, C.C.

    1984-01-01

    A program for automated task analysis is described. Called TAPS (task analysis profiling system), the program accepts normal English prose and outputs skills, knowledges, attitudes, and abilities (SKAAs) along with specific guidance and recommended ability measurement tests for nuclear power plant operators. A new method for defining SKAAs is presented along with a sample program output.

  19. Using Teacher Greetings to Increase Speed to Task Engagement

    ERIC Educational Resources Information Center

    Allday, R. Allan; Bush, Miranda; Ticknor, Nicole; Walker, Lindsay

    2011-01-01

    We used a multiple baseline design across participants to determine if teacher greetings would reduce the latency to task engagement. Three participants were identified by their respective teachers as having difficulty initiating task-appropriate engagement at the beginning of class. Latency was measured from teacher greeting until the participant…

  20. Developmental Complexity of the Stimuli Included in Mispronunciation Detection Tasks

    ERIC Educational Resources Information Center

    McNeill, Brigid C.; Hesketh, Anne

    2010-01-01

    Background: Phonological representations are important for speech and literacy development. Mispronunciation detection tasks have been proposed as an appropriate measure of phonological representations for children with speech disorder. There has been limited analysis, however, of the developmental complexity of task stimuli. Further, the tasks…

  1. Task-dependent color discrimination

    NASA Technical Reports Server (NTRS)

    Poirson, Allen B.; Wandell, Brian A.

    1990-01-01

    When color video displays are used in time-critical applications (e.g., head-up displays, video control panels), the observer must discriminate among briefly presented targets seen within a complex spatial scene. Color-discrimination threshold are compared by using two tasks. In one task the observer makes color matches between two halves of a continuously displayed bipartite field. In a second task the observer detects a color target in a set of briefly presented objects. The data from both tasks are well summarized by ellipsoidal isosensitivity contours. The fitted ellipsoids differ both in their size, which indicates an absolute sensitivity difference, and orientation, which indicates a relative sensitivity difference.

  2. Tasks and premises in quantum state determination

    NASA Astrophysics Data System (ADS)

    Carmeli, Claudio; Heinosaari, Teiko; Schultz, Jussi; Toigo, Alessandro

    2014-02-01

    The purpose of quantum tomography is to determine an unknown quantum state from measurement outcome statistics. There are two obvious ways to generalize this setting. First, our task need not be the determination of any possible input state but only some input states, for instance pure states. Second, we may have some prior information, or premise, which guarantees that the input state belongs to some subset of states, for instance the set of states with rank less than half of the dimension of the Hilbert space. We investigate state determination under these two supplemental features, concentrating on the cases where the task and the premise are statements about the rank of the unknown state. We characterize the structure of quantum observables (positive operator valued measures) that are capable of fulfilling these type of determination tasks. After the general treatment we focus on the class of covariant phase space observables, thus providing physically relevant examples of observables both capable and incapable of performing these tasks. In this context, the effect of noise is discussed.

  3. Extending the evaluation of Genia Event task toward knowledge base construction and comparison to Gene Regulation Ontology task

    PubMed Central

    2015-01-01

    Background The third edition of the BioNLP Shared Task was held with the grand theme "knowledge base construction (KB)". The Genia Event (GE) task was re-designed and implemented in light of this theme. For its final report, the participating systems were evaluated from a perspective of annotation. To further explore the grand theme, we extended the evaluation from a perspective of KB construction. Also, the Gene Regulation Ontology (GRO) task was newly introduced in the third edition. The final evaluation of the participating systems resulted in relatively low performance. The reason was attributed to the large size and complex semantic representation of the ontology. To investigate potential benefits of resource exchange between the presumably similar tasks, we measured the overlap between the datasets of the two tasks, and tested whether the dataset for one task can be used to enhance performance on the other. Results We report an extended evaluation on all the participating systems in the GE task, incoporating a KB perspective. For the evaluation, the final submission of each participant was converted to RDF statements, and evaluated using 8 queries that were formulated in SPARQL. The results suggest that the evaluation may be concluded differently between the two different perspectives, annotation vs. KB. We also provide a comparison of the GE and GRO tasks by converting their datasets into each other's format. More than 90% of the GE data could be converted into the GRO task format, while only half of the GRO data could be mapped to the GE task format. The imbalance in conversion indicates that the GRO is a comprehensive extension of the GE task ontology. We further used the converted GRO data as additional training data for the GE task, which helped improve GE task participant system performance. However, the converted GE data did not help GRO task participants, due to overfitting and the ontology gap. PMID:26202680

  4. Correlates of academic procrastination: discomfort, task aversiveness, and task capability.

    PubMed

    Milgram, N; Marshevsky, S; Sadeh, C

    1995-03-01

    The relationships among five aspects of academic procrastination--behavioral delay, personal upset about the delay, task aversiveness, task capability, and the desire to reduce behavioral delay--were investigated in 10th-grade Israeli students (N = 195). Upset about delay was weakly related to delay itself, and--unlike delay--was strongly related to perceived capability to perform academic tasks and to the desire to change delaying behavior. Students delayed more on academic tasks labeled unpleasant than pleasant, were neutral in between, and were correspondingly more upset about the former than the latter. They more frequently acknowledged reasons for academic procrastination that were less threatening to their self-image (e.g., problems in time management) than reasons that were more threatening (e.g., lack of ability). Interest in reducing delay is related more to self-perceived ability to handle tasks than to time spent procrastinating or reasons given for procrastinating.

  5. Sentiment Analysis of Suicide Notes: A Shared Task

    PubMed Central

    Pestian, John P.; Matykiewicz, Pawel; Linn-Gust, Michelle; South, Brett; Uzuner, Ozlem; Wiebe, Jan; Cohen, K. Bretonnel; Hurdle, John; Brew, Christopher

    2012-01-01

    This paper reports on a shared task involving the assignment of emotions to suicide notes. Two features distinguished this task from previous shared tasks in the biomedical domain. One is that it resulted in the corpus of fully anonymized clinical text and annotated suicide notes. This resource is permanently available and will (we hope) facilitate future research. The other key feature of the task is that it required categorization with respect to a large set of labels. The number of participants was larger than in any previous biomedical challenge task. We describe the data production process and the evaluation measures, and give a preliminary analysis of the results. Many systems performed at levels approaching the inter-coder agreement, suggesting that human-like performance on this task is within the reach of currently available technologies. PMID:22419877

  6. Sentiment Analysis of Suicide Notes: A Shared Task.

    PubMed

    Pestian, John P; Matykiewicz, Pawel; Linn-Gust, Michelle; South, Brett; Uzuner, Ozlem; Wiebe, Jan; Cohen, K Bretonnel; Hurdle, John; Brew, Christopher

    2012-01-30

    This paper reports on a shared task involving the assignment of emotions to suicide notes. Two features distinguished this task from previous shared tasks in the biomedical domain. One is that it resulted in the corpus of fully anonymized clinical text and annotated suicide notes. This resource is permanently available and will (we hope) facilitate future research. The other key feature of the task is that it required categorization with respect to a large set of labels. The number of participants was larger than in any previous biomedical challenge task. We describe the data production process and the evaluation measures, and give a preliminary analysis of the results. Many systems performed at levels approaching the inter-coder agreement, suggesting that human-like performance on this task is within the reach of currently available technologies.

  7. Static assignment of complex stochastic tasks using stochastic majorization

    NASA Technical Reports Server (NTRS)

    Nicol, David; Simha, Rahul; Towsley, Don

    1992-01-01

    We consider the problem of statically assigning many tasks to a (smaller) system of homogeneous processors, where a task's structure is modeled as a branching process, and all tasks are assumed to have identical behavior. We show how the theory of majorization can be used to obtain a partial order among possible task assignments. Our results show that if the vector of numbers of tasks assigned to each processor under one mapping is majorized by that of another mapping, then the former mapping is better than the latter with respect to a large number of objective functions. In particular, we show how measurements of finishing time, resource utilization, and reliability are all captured by the theory. We also show how the theory may be applied to the problem of partitioning a pool of processors for distribution among parallelizable tasks.

  8. Task Analysis for Health Occupations. Cluster: Rehabilitation Services. Occupation: Physical Therapist Assistant. Education for Employment Task Lists.

    ERIC Educational Resources Information Center

    Lathrop, Janice

    Task analyses are provided for two duty areas for the occupation of physical therapist assistant in the rehabilitation services cluster. Ten tasks are listed for the duty area "providing therapeutic measures": apply cold compress, administer hot soak, apply heat lamp, apply warm compress, apply ice bag, assist with dressing change, apply clean…

  9. Computer-Paced versus Experimenter-Paced Working Memory Span Tasks: Are They Equally Reliable and Valid?

    ERIC Educational Resources Information Center

    Bailey, Heather

    2012-01-01

    Working memory span tasks are popular measures, in part, because performance on these tasks predicts performance on other measures of cognitive ability. The traditional method of span-task administration is the experimenter-paced version, whose reliability and validity have been repeatedly demonstrated. However, computer-paced span tasks are…

  10. Task Models in the Digital Ocean

    ERIC Educational Resources Information Center

    DiCerbo, Kristen E.

    2014-01-01

    The Task Model is a description of each task in a workflow. It defines attributes associated with that task. The creation of task models becomes increasingly important as the assessment tasks become more complex. Explicitly delineating the impact of task variables on the ability to collect evidence and make inferences demands thoughtfulness from…

  11. Students' Engagement in Literacy Tasks

    ERIC Educational Resources Information Center

    Parsons, Seth A.; Malloy, Jacquelynn A.; Parsons, Allison Ward; Burrowbridge, Sarah Cohen

    2015-01-01

    This article offers insight into what makes literacy tasks engaging or disengaging based on observations of and interviews with students. In a yearlong study of a sixth-grade classroom in a Title I school, students engaged in integrated literacy-social studies instruction. Researchers studied the degree of task openness and the degree to which…

  12. Maximize Student Time on Task

    ERIC Educational Resources Information Center

    Peters, Erin

    2004-01-01

    Student time on task is the most influential factor in student achievement. High motivation and engagement in learning have consistently been linked to increased levels of student success. At the same time, a lack of interest in schoolwork becomes increasingly common in more and more middle school students. To maximize time on task, teachers need…

  13. Cosmetology Series. Duty Task List.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This document contains the occupational duty/task lists for three occupations in the cosmetology series. Each occupation is divided into a number of duties. A separate page for each duty in the occupation lists the tasks in that duty along with its code number and columns to indicate whether that particular duty has been taught and to provide…

  14. Teachers' Aides: Tasks and Concerns

    ERIC Educational Resources Information Center

    Balderson, James H.; Nixon, Mary

    1976-01-01

    Addresses three questions: (1) What tasks do aides perform? (2) Does training make a difference in the type of tasks aides perform? (3) What are the concerns of aides? (Available from the Department of Educational Administration, The University of Alberta, Edmonton, Alberta, Canada T6G 2G5; $0.50, single copy.) (Author/IRT)

  15. Science 102: This Month's Task

    ERIC Educational Resources Information Center

    Robertson, Bill

    2015-01-01

    This task asks readers to figure out why when you stir a cup of hot liquid and tap on the side of the cup with a spoon, the pitch of sound starts low and ends up high. The solution to last month's tasks relating to the circumference of the Earth and how many stars are in the (visible) sky is also presented.

  16. Drafting Series. Duty Task List.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This task list is intended for use in planning and/or evaluating a competency-based course in drafting. The tasks required to perform the duties of seven types of drafters (i.e., general, architectural, electronic, civil, structural, mechanical, and process pipe drafters) and technical illustrators are outlined. The following are among the duties…

  17. Receptionist: Task List Competency Record.

    ERIC Educational Resources Information Center

    Minnesota Instructional Materials Center, White Bear Lake.

    One of a series of 12 in the secretarial/clerical area, this booklet for the vocational instructor contains a job description for the receptionist, a task list of areas of competency, an occupational tasks competency record (suggested as replacement for the traditional report card), a list of industry representatives and educators involved in…

  18. TASK: Anarchy in the Artroom

    ERIC Educational Resources Information Center

    Schubert, Cynthia; Van Patten, Kelda

    2012-01-01

    Most teenagers do not really like to be told what to do. For that matter, most adults don't either. This article discusses contemporary artist Oliver Herring's TASK, which is an opportunity for participants to bend or define the rules on their own terms. It is about choice, and, for many, it is a dream come true. TASK is controlled chaos that can…

  19. What Makes a Rich Task?

    ERIC Educational Resources Information Center

    Griffin, Pete

    2009-01-01

    A common view seems to be emerging in the mathematics education world at the moment that the development and use of "rich tasks" is a good thing; a "right thing" to do. There are many examples of these "rich tasks" and teachers are encouraged to use them whenever they can. Professional learners don't just accept this uncritically, but question…

  20. Task Switching: A PDP Model

    ERIC Educational Resources Information Center

    Gilbert, Sam J.; Shallice, Tim

    2002-01-01

    When subjects switch between a pair of stimulus-response tasks, reaction time is slower on trial N if a different task was performed on trial N--1. We present a parallel distributed processing (PDP) model that simulates this effect when subjects switch between word reading and color naming in response to Stroop stimuli. Reaction time on "switch…

  1. Electricity Series. Duty Task List.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This task list is intended for use in planning and/or evaluating a competency-based course in electricity. The guide outlines the tasks entailed in 10 different duties typically required of employees in the following occupations: residential electrician apprentice, material handler/supply clerk, maintenance electrician apprentice,…

  2. Putting Mathematical Tasks into Context

    ERIC Educational Resources Information Center

    Nagle, Courtney R.; Styers, Jodie L.

    2015-01-01

    Although many factors affect students' mathematical activity during a lesson, the teacher's selection and implementation of tasks is arguably the most influential in determining the level of student engagement. Mathematical tasks are intended to focus students' attention on a particular mathematical concept and it is the careful developing and…

  3. Welding Series. Duty Task List.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This document contains the occupational duty/task lists for six occupations in the welding series. Each occupation is divided into a number of duties. A separate page for each duty in the occupation lists the tasks in that duty along with its code number and columns to indicate whether that particular duty has been taught and to provide space for…

  4. Horticulture Series. Duty Task List.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This document contains the occupational duty/task lists for 9 occupations in the horticulture series. Each occupation is divided into a number of duties. A separate page for each duty in the occupation lists the tasks in that duty along with its code number and columns to indicate whether that particular duty has been taught and to provide space…

  5. Group Motivation and Group Task Performance: The Expectancy-Valence Theory Approach.

    ERIC Educational Resources Information Center

    Nakanishi, Masayuki

    1988-01-01

    Investigated effects of group motivation on group task performance. Created two levels of valence, expectancy and instrumentality. Valence variable reflected on group productivity on unstructured and task persistence measures. Expectancy variable's effect was on task persistence measure. Instrumentality affected group productivity on structured…

  6. Task Attention Facilitates Learning of Task-Irrelevant Stimuli

    PubMed Central

    Huang, Tsung-Ren; Watanabe, Takeo

    2012-01-01

    Attention plays a fundamental role in visual learning and memory. One highly established principle of visual attention is that the harder a central task is, the more attentional resources are used to perform the task and the smaller amount of attention is allocated to peripheral processing because of limited attention capacity. Here we show that this principle holds true in a dual-task setting but not in a paradigm of task-irrelevant perceptual learning. In Experiment 1, eight participants were asked to identify either bright or dim number targets at the screen center and to remember concurrently presented scene backgrounds. Their recognition performances for scenes paired with dim/hard targets were worse than those for scenes paired with bright/easy targets. In Experiment 2, eight participants were asked to identify either bright or dim letter targets at the screen center while a task-irrelevant coherent motion was concurrently presented in the background. After five days of training on letter identification, participants improved their motion sensitivity to the direction paired with hard/dim targets improved but not to the direction paired with easy/bright targets. Taken together, these results suggest that task-irrelevant stimuli are not subject to the attentional control mechanisms that task-relevant stimuli abide. PMID:22563424

  7. Illinois task force on global climate change

    SciTech Connect

    Griffin, B.S.

    1996-12-31

    The purpose of this report is to document progress in the areas of national policy development, emissions reduction, research and education, and adaptation, and to identify specific actions that will be undertaken to implement the Illinois state action plan. The task force has been tracking national and international climate change policy, and helping shape national policy agenda. Identification and implementation of cost-effective mitigation measures has been performed for emissions reduction. In the area of research and education, the task force is developing the capacity to measure climate change indicators, maintaining and enhancing Illinois relevant research, and strengthening climate change education. Activities relevant to adaptation to new policy include strengthening water laws and planning for adaptation. 6 figs., 4 tabs.

  8. Age-related differences in multiple task monitoring.

    PubMed

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

    2014-01-01

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

  9. Age-Related Differences in Multiple Task Monitoring

    PubMed Central

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

    2014-01-01

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

  10. Near-infrared spectroscopy assessment of divided visual attention task-invoked cerebral hemodynamics during prolonged true driving

    NASA Astrophysics Data System (ADS)

    Li, Ting; Zhao, Yue; Sun, Yunlong; Gao, Yuan; Su, Yu; Hetian, Yiyi; Chen, Min

    2015-03-01

    Driver fatigue is one of the leading causes of traffic accidents. It is imperative to develop a technique to monitor fatigue of drivers in real situation. Near-infrared spectroscopy (fNIRS) is now capable of measuring brain functional activity noninvasively in terms of hemodynamic responses sensitively, which shed a light to us that it may be possible to detect fatigue-specified brain functional activity signal. We developed a sensitive, portable and absolute-measure fNIRS, and utilized it to monitor cerebral hemodynamics on car drivers during prolonged true driving. An odd-ball protocol was employed to trigger the drivers' visual divided attention, which is a critical function in safe driving. We found that oxyhemoglobin concentration and blood volume in prefrontal lobe dramatically increased with driving duration (stand for fatigue degree; 2-10 hours), while deoxyhemoglobin concentration increased to the top at 4 hours then decreased slowly. The behavior performance showed clear decrement only after 6 hours. Our study showed the strong potential of fNIRS combined with divided visual attention protocol in driving fatigue degree monitoring. Our findings indicated the fNIRS-measured hemodynamic parameters were more sensitive than behavior performance evaluation.

  11. Effects of pitch distance and likelihood on the perceived duration of deviant auditory events.

    PubMed

    Kim, Elisa; McAuley, J Devin

    2013-10-01

    When a deviant (oddball) stimulus is presented within a series of otherwise identical (standard) stimuli, the duration of the oddball tends to be overestimated. Two experiments investigated factors affecting systematic distortions in the perceived duration of oddball stimuli. Both experiments used an auditory oddball paradigm where oddball tones varied in both their pitch distance from the pitch of a standard tone and their likelihood of occurrence. Experiment 1 revealed that (1) far-pitch oddballs were perceived to be longer than near-pitch oddballs, (2) effects of pitch distance were greater in low-likelihood conditions, and (3) oddballs in later serial positions were perceived to be longer than oddballs in earlier serial positions. The above effects held regardless of whether oddballs were higher or lower in pitch than the standard. Experiment 2 revealed a pattern of response times in an oddball detection task that generally paralleled the pattern of data observed in Experiment 1; across conditions, there was a negative correlation between detection times and perceived duration. Taken together, the results suggest that the observed effects of oddball pitch, likelihood, and position on perceived duration are at least partly driven by how quickly individuals are able to initiate timing the oddball following its onset. Implications for different theoretical accounts of the oddball effect are discussed.

  12. Task E container corrosion studies: Annual report

    SciTech Connect

    Bunnell, L.R.; Doremus, L.A.; Topping, J.B.; Duncan, D.R.

    1994-06-01

    The Pacific Northwest Laboratory is conducting the Solid Waste Technology Support Program (SWTSP) for Westinghouse Hanford Company (WHC). Task E is the Container Corrosion Study Portion of the SWTSP that will perform testing to provide defensible data on the corrosion of low-carbon steel, as used in drums to contain chemical and radioactive wastes at the Hanford Site. A second objective of Task E is to provide and test practical alternative materials that have higher corrosion resistance than low-carbon steel. The scope of work for fiscal year (FY) 1993 included initial testing of mild steel specimens buried in Hanford soils or exposed to atmospheric corrosion in metal storage sheds. During FY 1993, progress was made in three areas of Task E. First, exposure of test materials began at the Soil Corrosion Test Site where low-carbon steel specimens were placed in the soil in five test shafts at depths of 9 m (30 ft). Second, the corrosion measurement of low-carbon steel in the soil of two solid waste trenches continued. The total exposure time is {approx} 500 days. Third, an atmospheric corrosion test of low-carbon steel was put initiated in a metal shed (Building 2401-W) in the 200 West Area. This annual report describes the Task E efforts and provides a current status.

  13. Real-time design with peer tasks

    NASA Technical Reports Server (NTRS)

    Goforth, Andre; Howes, Norman R.; Wood, Jonathan D.; Barnes, Michael J.

    1995-01-01

    We introduce a real-time design methodology for large scale, distributed, parallel architecture, real-time systems (LDPARTS), as an alternative to those methods using rate or dead-line monotonic analysis. In our method the fundamental units of prioritization, work items, are domain specific objects with timing requirements (deadlines) found in user's specification. A work item consists of a collection of tasks of equal priority. Current scheduling theories are applied with artifact deadlines introduced by the designer whereas our method schedules work items to meet user's specification deadlines (sometimes called end-to-end deadlines). Our method supports these scheduling properties. Work item scheduling is based on domain specific importance instead of task level urgency and still meets as many user specification deadlines as can be met by scheduling tasks with respect to urgency. Second, the minimum (closest) on-line deadline that can be guaranteed for a work item of highest importance, scheduled at run time, is approximately the inverse of the throughput, measured in work items per second. Third, throughput is not degraded during overload and instead of resorting to task shedding during overload, the designer can specify which work items to shed. We prove these properties in a mathematical model.

  14. 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.

  15. Cardiac data increase association between self-report and both expert ratings of task load and task performance in flight simulator tasks: An exploratory study.

    PubMed

    Lehrer, Paul; Karavidas, Maria; Lu, Shou-En; Vaschillo, Evgeny; Vaschillo, Bronya; Cheng, Andrew

    2010-05-01

    Seven professional airplane pilots participated in a one-session test in a Boeing 737-800 simulator. Mental workload for 18 flight tasks was rated by experienced test pilots (hereinafter called "expert ratings") and by study participants' self-report on NASA's Task Load Index (TLX) scale. Pilot performance was rated by a check pilot. The standard deviation of R-R intervals (SDNN) significantly added 3.7% improvement over the TLX in distinguishing high from moderate-load tasks and 2.3% improvement in distinguishing high from combined moderate and low-load tasks. Minimum RRI in the task significantly discriminated high- from medium- and low-load tasks, but did not add significant predictive variance to the TLX. The low-frequency/high-frequency (LF:HF) RRI ratio based on spectral analysis of R-R intervals, and ventricular relaxation time were each negatively related to pilot performance ratings independently of TLX values, while minimum and average RRI were positively related, showing added contribution of these cardiac measures for predicting performance. Cardiac results were not affected by controlling either for respiration rate or motor activity assessed by accelerometry. The results suggest that cardiac assessment can be a useful addition to self-report measures for determining flight task mental workload and risk for performance decrements. Replication on a larger sample is needed to confirm and extend the results.

  16. Task conflicts and exclusive professionalism in nursing in South Korea.

    PubMed

    Jung, Minsoo

    2014-01-01

    Task conflicts among medical professions are essential problems to be solved in health care organizations. This study examined job conflicts between practical nurses (PNs) and registered nurses (RNs) in their duties and tasks with representative panelists from South Korea. This qualitative study used the Dacum Task Analysis process. Subject-matter experts in practical nursing were recruited utilizing stratified sampling: Ten experts developed job descriptions of PNs, and 20 validated the descriptions. The on-site tasks and duties of the PNs were measured by means of Dacum, and the results were reviewed by RNs using 3 focus-group interviews. The job description of PNs consisted of 10 duties and 117 tasks, overlapping with some tasks of RNs. Core tasks performed by PNs, such as invasive activities, led to task conflicts between the 2 groups, as these activities were regarded as the inherent duty of nursing professions. Thus, the RNs did not concede the expanded job scope of the PNs in terms of exclusive professionalism. To reduce task conflict, there is a need for the balanced development of nursing professionalism.

  17. Accommodation in Astigmatic Children During Visual Task Performance

    PubMed Central

    Harvey, Erin M.; Miller, Joseph M.; Apple, Howard P.; Parashar, Pavan; Twelker, J. Daniel; Crescioni, Mabel; Davis, Amy L.; Leonard-Green, Tina K.; Campus, Irene; Sherrill, Duane L.

    2014-01-01

    Purpose. To determine the accuracy and stability of accommodation in uncorrected children during visual task performance. Methods. Subjects were second- to seventh-grade children from a highly astigmatic population. Measurements of noncycloplegic right eye spherical equivalent (Mnc) were obtained while uncorrected subjects performed three visual tasks at near (40 cm) and distance (2 m). Tasks included reading sentences with stimulus letter size near acuity threshold and an age-appropriate letter size (high task demands) and viewing a video (low task demand). Repeated measures ANOVA assessed the influence of astigmatism, task demand, and accommodative demand on accuracy (mean Mnc) and variability (mean SD of Mnc) of accommodation. Results. For near and distance analyses, respectively, sample size was 321 and 247, mean age was 10.37 (SD 1.77) and 10.30 (SD 1.74) years, mean cycloplegic M was 0.48 (SD 1.10) and 0.79 diopters (D) (SD 1.00), and mean astigmatism was 0.99 (SD 1.15) and 0.75 D (SD 0.96). Poor accommodative accuracy was associated with high astigmatism, low task demand (video viewing), and high accommodative demand. The negative effect of accommodative demand on accuracy increased with increasing astigmatism, with the poorest accommodative accuracy observed in high astigmats (≥3.00 D) with high accommodative demand/high hyperopia (1.53 D and 2.05 D of underaccommodation for near and distant stimuli, respectively). Accommodative variability was greatest in high astigmats and was uniformly high across task condition. No/low and moderate astigmats showed higher variability for the video task than the reading tasks. Conclusions. Accuracy of accommodation is reduced in uncorrected children with high astigmatism and high accommodative demand/high hyperopia, but improves with increased visual task demand (reading). High astigmats showed the greatest variability in accommodation. PMID:25103265

  18. The cooking task: making a meal of executive functions

    PubMed Central

    Doherty, T. A.; Barker, L. A.; Denniss, R.; Jalil, A.; Beer, M. D.

    2015-01-01

    Current standardized neuropsychological tests may fail to accurately capture real-world executive deficits. We developed a computer-based Cooking Task (CT) assessment of executive functions and trialed the measure with a normative group before use with a head-injured population. Forty-six participants completed the computerized CT and subtests from standardized neuropsychological tasks, including the Tower and Sorting Tests of executive function from the Delis-Kaplan Executive Function System (D-KEFS) and the Cambridge prospective memory test (CAMPROMPT), in order to examine whether standardized executive function tasks, predicted performance on measurement indices from the CT. Findings showed that verbal comprehension, rule detection and prospective memory contributed to measures of prospective planning accuracy and strategy implementation of the CT. Results also showed that functions necessary for cooking efficacy differ as an effect of task demands (difficulty levels). Performance on rule detection, strategy implementation and flexible thinking executive function measures contributed to accuracy on the CT. These findings raise questions about the functions captured by present standardized tasks particularly at varying levels of difficulty and during dual-task performance. Our preliminary findings also indicate that CT measures can effectively distinguish between executive function and Full Scale IQ abilities. Results of the present study indicate that the CT shows promise as an ecologically valid measure of executive function for future use with a head-injured population and indexes selective executive function’s captured by standardized tests. PMID:25717294

  19. Cognitive correlates of hemispheric performance on dichotic tasks.

    PubMed

    Johnson, R C; Green, P; Ahern, F M; Cole, R E

    Older (age 50+) adults were tested twice on three measures of dichotic memory and once on three measures of cognition. Internal consistencies of all three measures generally were adequate. However, test-retest reliabilities, by ear of presentation, were comparatively low for the three dichotic measures. A measure of vocabulary (a left hemisphere dominant cognitive ability) was related to performance on most dichotic tasks. Years of education (an index of left hemisphere mediated crystallized intelligence) was related to performance on left but not right hemisphere function on two of three dichotic tasks. Performance on tests of spatial ability was related to performance on left ear/right hemisphere but not right ear/left hemisphere function on two of three dichotic memory tasks. Individual differences in accuracy of recall and recognition of stimuli presented via dichotic tasks to the right ear/left hemisphere and the left ear/right hemisphere appear to have different cognitive correlates. Right hemisphere performance on dichotic tasks generally shows a significant negative association with age, as did performance on right hemisphere dominant cognitive tasks. On the other hand, most measures of left hemisphere performance showed no decline associated with age.

  20. Operation Ivy. Report of commander, Task Group 132. 1. Pacific Proving Grounds. Joint Task Force 132

    SciTech Connect

    Burriss, S.W.

    1984-10-31

    The mission of the Task Group included the responsibilities to conduct experimental measurement programs on Shots Mike and King and to conduct the radiological safety program. Programs were established to make radiochemical analysis of bomb debris; to follow the progress of the nuclear reaction; to make neutron, gamma-ray, blast, thermal radiation, and electromagnetic measurements; and to make a preliminary geophysical and marine survey of the test area. The organizational structure and command relations to accomplish the mission are outlined.

  1. Quantum tasks in Minkowski space

    NASA Astrophysics Data System (ADS)

    Kent, Adrian

    2012-11-01

    The fundamental properties of quantum information and its applications to computing and cryptography have been greatly illuminated by considering information-theoretic tasks that are provably possible or impossible within non-relativistic quantum mechanics. I describe here a general framework for defining tasks within (special) relativistic quantum theory and illustrate it with examples from relativistic quantum cryptography and relativistic distributed quantum computation. The framework gives a unified description of all tasks previously considered and also defines a large class of new questions about the properties of quantum information in relation to Minkowski causality. It offers a way of exploring interesting new fundamental tasks and applications, and also highlights the scope for a more systematic understanding of the fundamental information-theoretic properties of relativistic quantum theory.

  2. Physiological monitoring of team and task stressors

    NASA Astrophysics Data System (ADS)

    Orasanu, Judith; Tada, Yuri; Kraft, Norbert; Fischer, Ute

    2005-05-01

    Sending astronauts into space, especially on long-durations missions (e.g. three-year missions to Mars), entails enormous risk. Threats include both physical dangers of radiation, bone loss and other consequences of weightlessness, and also those arising from interpersonal problems associated with extended life in a high-risk isolated and confined environment. Before undertaking long-duration missions, NASA seeks to develop technologies to monitor indicators of potentially debilitating stress at both the individual and team level so that countermeasures can be introduced to prevent further deterioration. Doing so requires a better understanding of indicators of team health and performance. To that end, a study of team problem solving in a simulation environment was undertaken to explore effects of team and task stress. Groups of four males (25-45 yrs) engaged in six dynamic computer-based Antarctic search and rescue missions over four days. Both task and team stressors were manipulated. Physiological responses (ECG, respiration rate and amplitude, SCL, EMG, and PPG); communication (voice and email); individual personality and subjective team dynamics responses were collected and related to task performance. Initial analyses found that physiological measures can be used to identify transient stress, predict performance, and reflect subjective workload. Muscle tension and respiration were the most robust predictors. Not only the level of arousal but its variability during engagement in the task is important to consider. In general, less variability was found to be associated with higher levels of performance. Individuals scoring high on specific personality characteristics responded differently to task stress.

  3. Annual Progress report - General Task

    SciTech Connect

    Wesnousky, S.G.

    1993-09-30

    This report provides a summary of progress for the project {open_quotes}Evaluation of the Geologic Relations and Seismotectonic Stability of the Yucca Mountain Area, Nevada Nuclear Waste Site Investigation (NNWSI).{close_quotes} A similar report was previously provided for the period of 1 October 1991 to 30 September 1992. The report initially covers the activities of the General Task and is followed by sections that describe the progress of the other ongoing tasks.

  4. Dissociation between spontaneously hypertensive (SHR) andWistar–Kyoto (WKY) rats in baseline performance and methylphenidate response on measures of attention, impulsivity and hyperactivity in a Visual Stimulus Position Discrimination Task

    SciTech Connect

    Thanos, P.K.

    2009-10-08

    The spontaneously hypertensive rat (SHR) is a widely accepted rodent model of Attention Deficit/Hyperactivity Disorder (ADHD), and methylphenidate (MP) is a central nervous systemstimulant that has been shown to have a dose-related positive effect on attention task performance in humans with ADHD. The current study was undertaken to compare SHR to its typical control strain, Wistar-Kyoto(WKY) rats, on the performance of a Visual Stimulus Position Discrimination Task (VSPDT) as well as of the responsiveness of the two rat strains to MP treatment. The rats were initially trained on the VSPDT, in which a light cue was presented randomly at three different cue-light intervals (1 s, 300 ms and 100 ms) over one of two levers, and presses on the lever corresponding to the light cue were reinforced with a food pellet. Once rats reached stable performance, the treatment phase of the study began, during which they received daily intraperitoneal (IP) injections of saline, 2 mg/kg, 5 mg/kg, and 10 mg/kg of MP in a randomized order immediately prior to being tested on the VSPDT. Baseline performance accuracy on the VSPDT did not differ between the groups. Furthermore, a striking strain dissociation was evident in the response of the two strains to treatment; VSPDT performance was substantially disrupted by the 5 and 10 mg/kg dose in the WKY rats but only mildly in the SHR rats. Response omissions were also increased only in WKY rats. Finally, both strains had increased locomotor activity in the operant chamber following MP treatment. These findings point to an important difference in response tendency toMP in the two strains that supports a view that a critical difference between these strains may suggest neurochemical and neuroadaptive differences associated with the behavioral impairments of ADHD.

  5. Voluntary Task Switching: Chasing the Elusive Homunculus

    ERIC Educational Resources Information Center

    Arrington, Catherine M.; Logan, Gordon D.

    2005-01-01

    In the voluntary task switching procedure, subjects choose the task to perform on a series of bivalent stimuli, requiring top-down control of task switching. Experiments 1-3 contrasted voluntary task switching and explicit task cuing. Choice behavior showed small, inconsistent effects of external stimulus characteristics, supporting the assumption…

  6. 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

  7. Biocybernetic Control of Vigilance Task Parameters

    NASA Technical Reports Server (NTRS)

    Freeman, Frederick G.

    2000-01-01

    The major focus of the present proposal was to examine psychophysiological variables that are related to hazardous states of awareness induced by monitoring automated systems. With the increased use of automation in today's work environment, people's roles in the work place are being redefined from that of active participant to one of passive monitor. Although the introduction of automated systems has a number of benefits, there are also a number of disadvantages regarding the worker performance. Byrne and Parasuraman (1996) have argued for the use of psychophysiological measures in both the development and the implementation of adaptive automation. While both performance based and model based adaptive automation have been studied, the use of psychophysiological measures, especially EEG, offers the advantage of real time evaluation of the state of the subject. Previous investigations of the closed-loop adaptive automation system in our laboratory, supported by NASA, have employed a compensatory tracking task which involved the use of a joystick to maintain the position of a cursor in the middle of a video screen. This research demonstrated that, in an adaptive automation, closed-loop environment, subjects perform a tracking task better under a negative, compared to a positive, feedback condition. While tracking is comparable to some aspects of flying an airplane, it does not simulate the environment found in the cockpit of modern commercial airplanes. Since a large part of the flying responsibilities in commercial airplanes is automated, the primary responsibility of pilots is to monitor the automation and to respond when the automation fails. Because failures are relatively rare, pilots often suffer from hazardous states of awareness induced by long term vigilance of the automated system. Consequently, the aim of the current study was to investigate the ability of the closed-loop, adaptive automation system in a vigilance paradigm. It is also important to note

  8. Flexible connectivity in the aging brain revealed by task modulations.

    PubMed

    Geerligs, Linda; Saliasi, Emi; Renken, Remco J; Maurits, Natasha M; Lorist, Monicque M

    2014-08-01

    Recent studies have shown that aging has a large impact on connectivity within and between functional networks. An open question is whether elderly still have the flexibility to adapt functional network connectivity (FNC) to the demands of the task at hand. To study this, we collected fMRI data in younger and older participants during resting state, a selective attention (SA) task and an n-back working memory task with varying levels of difficulty. Spatial independent component (IC) analysis was used to identify functional networks over all participants and all conditions. Dual regression was used to obtain participant and task specific time-courses per IC. Subsequently, functional connectivity was computed between all ICs in each of the tasks. Based on these functional connectivity matrices, a scaled version of the eigenvector centrality (SEC) was used to measure the total influence of each IC in the complete graph of ICs. The results demonstrated that elderly remain able to adapt FNC to task demands. However, there was an age-related shift in the impetus for FNC change. Older participants showed the maximal change in SEC patterns between resting state and the SA task. Young participants, showed the largest shift in SEC patterns between the less demanding SA task and the more demanding 2-back task. Our results suggest that increased FNC changes from resting state to low demanding tasks in elderly reflect recruitment of additional resources, compared with young adults. The lack of change between the low and high demanding tasks suggests that elderly reach a resource ceiling. PMID:24382835

  9. Flexible connectivity in the aging brain revealed by task modulations.

    PubMed

    Geerligs, Linda; Saliasi, Emi; Renken, Remco J; Maurits, Natasha M; Lorist, Monicque M

    2014-08-01

    Recent studies have shown that aging has a large impact on connectivity within and between functional networks. An open question is whether elderly still have the flexibility to adapt functional network connectivity (FNC) to the demands of the task at hand. To study this, we collected fMRI data in younger and older participants during resting state, a selective attention (SA) task and an n-back working memory task with varying levels of difficulty. Spatial independent component (IC) analysis was used to identify functional networks over all participants and all conditions. Dual regression was used to obtain participant and task specific time-courses per IC. Subsequently, functional connectivity was computed between all ICs in each of the tasks. Based on these functional connectivity matrices, a scaled version of the eigenvector centrality (SEC) was used to measure the total influence of each IC in the complete graph of ICs. The results demonstrated that elderly remain able to adapt FNC to task demands. However, there was an age-related shift in the impetus for FNC change. Older participants showed the maximal change in SEC patterns between resting state and the SA task. Young participants, showed the largest shift in SEC patterns between the less demanding SA task and the more demanding 2-back task. Our results suggest that increased FNC changes from resting state to low demanding tasks in elderly reflect recruitment of additional resources, compared with young adults. The lack of change between the low and high demanding tasks suggests that elderly reach a resource ceiling.

  10. The effect of processing code, response modality and task difficulty on dual task performance and subjective workload in a manual system

    NASA Technical Reports Server (NTRS)

    Liu, Yili; Wickens, Christopher D.

    1987-01-01

    This paper reports on the first experiment of a series studying the effect of task structure and difficulty demand on time-sharing performance and workload in both automated and corresponding manual systems. The experimental task involves manual control time-shared with spatial and verbal decisions tasks of two levels of difficulty and two modes of response (voice or manual). The results provide strong evidence that tasks and processes competing for common processing resources are time shared less effecively and have higher workload than tasks competing for separate resources. Subjective measures and the structure of multiple resources are used in conjunction to predict dual task performance. The evidence comes from both single-task and from dual-task performance.

  11. Visual Attention Allocation Between Robotic Arm and Environmental Process Control: Validating the STOM Task Switching Model

    NASA Technical Reports Server (NTRS)

    Wickens, Christopher; Vieanne, Alex; Clegg, Benjamin; Sebok, Angelia; Janes, Jessica

    2015-01-01

    Fifty six participants time shared a spacecraft environmental control system task with a realistic space robotic arm control task in either a manual or highly automated version. The former could suffer minor failures, whose diagnosis and repair were supported by a decision aid. At the end of the experiment this decision aid unexpectedly failed. We measured visual attention allocation and switching between the two tasks, in each of the eight conditions formed by manual-automated arm X expected-unexpected failure X monitoring- failure management. We also used our multi-attribute task switching model, based on task attributes of priority interest, difficulty and salience that were self-rated by participants, to predict allocation. An un-weighted model based on attributes of difficulty, interest and salience accounted for 96 percent of the task allocation variance across the 8 different conditions. Task difficulty served as an attractor, with more difficult tasks increasing the tendency to stay on task.

  12. Electroencephalographic Coherence and Learning: Distinct Patterns of Change during Word Learning and Figure Learning Tasks

    ERIC Educational Resources Information Center

    Collins, Peter; Hogan, Michael; Kilmartin, Liam; Keane, Michael; Kaiser, Jochen; Fischer, Kurt

    2010-01-01

    One likely mechanism in learning new skills is change in synchronous connections between distributed neural networks, which can be measured by coherence analysis of electroencephalographic patterns. This study examined coherence changes during the learning of two tasks, a word association task and a figure association task. Although learning…

  13. Second Language Learning with the Story Maze Task: Examining the Training Effect of Weaving through Stories

    ERIC Educational Resources Information Center

    Enkin, Elizabeth

    2016-01-01

    The maze task is a psycholinguistic experimental procedure that measures real-time incremental sentence processing. The task has recently been tested as a language learning tool with promising results. Therefore, the present study examines the merits of a contextualized version of this task: the story maze. The findings are consistent with…

  14. The Influence of Achievement Goal Orientations and Task Concreteness on Situational Interest

    ERIC Educational Resources Information Center

    Tapola, Anna; Jaakkola, Tomi; Niemivirta, Markku

    2014-01-01

    This study investigated changes in elementary school students' (n = 140) situational interest as a function of achievement goal orientation profiles and task characteristics. The authors repeatedly measured situational interest during a simulated science learning task in 2 task conditions that differed in the concreteness of the task…

  15. Effects of Task Familiarity on Stress Responses of Repressors and Sensitizers

    ERIC Educational Resources Information Center

    Pagano, Don F.

    1973-01-01

    R.S. Lazarus's theory of coping was used to investigate appraisal and reappraisal of threat in repressors and sensitizers. Two indexes of stress, self-report ratings of affect and palmar skin conductance, were measured prior to performance on a reaction time task, after one-third of the task was completed and after two-thirds of the task was…

  16. Task Performance and Response to Frustration in Children with Attention Deficit Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Scime, Melinda; Norvilitis, Jill M.

    2006-01-01

    The present study examined performance on an arithmetic task of increasing difficulty and a frustrating puzzle task for children with ADHD and comparison children. Emotional competence also was investigated in the two groups. Sixty-four children, 21 previously diagnosed with ADHD, participated. Performance on the arithmetic task was measured in…

  17. Comparative evaluation of workload estimation techniques in piloting tasks

    NASA Technical Reports Server (NTRS)

    Wierwille, W. W.

    1983-01-01

    Techniques to measure operator workload in a wide range of situations and tasks were examined. The sensitivity and intrusion of a wide variety of workload assessment techniques in simulated piloting tasks were investigated. Four different piloting tasks, psychomotor, perceptual, mediational, and communication aspects of piloting behavior were selected. Techniques to determine relative sensitivity and intrusion were applied. Sensitivity is the relative ability of a workload estimation technique to discriminate statistically significant differences in operator loading. High sensitivity requires discriminable changes in score means as a function of load level and low variation of the scores about the means. Intrusion is an undesirable change in the task for which workload is measured, resulting from the introduction of the workload estimation technique or apparatus.

  18. A study on task difficulty and acceleration stress

    NASA Technical Reports Server (NTRS)

    Repperger, D. W.; Rogers, D. B.

    1981-01-01

    The results of two experiments which relate to task difficulty and the effects of environmental stress on tracking performance are discussed and compared to subjective evaluations. The first experiment involved five different sum of sine tracking tasks which humans tracked both in a static condition and under a 5 Gz acceleration stress condition. The second experiment involved similar environmental stress conditions but in this case the tasks were constructed from deterministic functions with specially designed velocity and acceleration profiles. Phase Plane performance analysis was conducted to study potential measures of workload or tracking difficulty.

  19. Authentic Tasks Online: A Synergy among Learner, Task, and Technology

    ERIC Educational Resources Information Center

    Herrington, Jan; Reeves, Thomas C.; Oliver, Ron

    2006-01-01

    Fostering synergies amongst "learner," "task," and "technology" to create innovative and immersive distance learning environments runs counter to the widespread practice of incorporating traditional classroom pedagogical strategies into Web-based delivery of courses. The most widely accepted model of online higher education appears to be one of…

  20. Task Lists for Industrial Occupations. Education for Employment Task Lists.

    ERIC Educational Resources Information Center

    Dimmlich, David

    These cluster matrices provide duties and tasks that form the basis of instructional content for secondary, postsecondary, and adult occupational training programs for industrial occupations. Duties and skills are presented for the following: (1) electric home appliance and power tool repairers; (2) office machine/cash register repairer; (3)…

  1. A task is a task is a task: putting complex span, n-back, and other working memory indicators in psychometric context

    PubMed Central

    Schmiedek, Florian; Lövdén, Martin; Lindenberger, Ulman

    2014-01-01

    Based on a meta-analysis, Redick and Lindsey (2013) found that complex span and n-back tasks show an average correlation of r = 0.20, and concluded that “complex span and n-back tasks cannot be used interchangeably as working memory measures in research applications” (p. 1102). Here, we comment on this conclusion from a psychometric perspective. In addition to construct variance, performance on a test contains measurement error, task-specific variance, and paradigm-specific variance. Hence, low correlations among dissimilar indicators do not provide strong evidence for the existence, or absence, of a construct common to both indicators. One way to arrive at such evidence is to fit hierarchical latent factors that model task-specific, paradigm-specific, and construct variance. We report analyses for 101 younger and 103 older adults who worked on nine different working memory tasks. The data are consistent with a hierarchical model of working memory, according to which both complex span and n-back tasks are valid indicators of working memory. The working memory factor predicts 71% of the variance in a factor of reasoning among younger adults (83% for among older adults). When the working memory factor was restricted to any possible triplet of working memory tasks, the correlation between working memory and reasoning was inversely related to the average magnitude of the correlations among the indicators, indicating that more highly intercorrelated indicators may provide poorer coverage of the construct space. We stress the need to go beyond specific tasks and paradigms when studying higher-order cognitive constructs, such as working memory. PMID:25566149

  2. Working Memory, Task Switching, and Executive Control in the Task Span Procedure

    ERIC Educational Resources Information Center

    Logan, Gordon D.

    2004-01-01

    Four experiments explored the task span procedure: Subjects received lists of 1-10 task names to remember and then lists of 1-10 stimuli on which to perform the tasks. Task span is the number of tasks performed in order perfectly. Experiment 1 compared the task span with the traditional memory span in 6 practiced subjects and found little…

  3. What Do We Really Know about Cognitive Inhibition? Task Demands and Inhibitory Effects across a Range of Memory and Behavioural Tasks

    PubMed Central

    Noreen, Saima; MacLeod, Malcolm D.

    2015-01-01

    Our study explores inhibitory control across a range of widely recognised memory and behavioural tasks. Eighty-seven never-depressed participants completed a series of tasks designed to measure inhibitory control in memory and behaviour. Specifically, a variant of the selective retrieval-practice and the Think/No-Think tasks were employed as measures of memory inhibition. The Stroop-Colour Naming and the Go/No-Go tasks were used as measures of behavioural inhibition. Participants completed all 4 tasks. Task presentation order was counterbalanced across 3 separate testing sessions for each participant. Standard inhibitory forgetting effects emerged on both memory tasks but the extent of forgetting across these tasks was not correlated. Furthermore, there was no relationship between memory inhibition tasks and either of the main behavioural inhibition measures. At a time when cognitive inhibition continues to gain acceptance as an explanatory mechanism, our study raises fundamental questions about what we actually know about inhibition and how it is affected by the processing demands of particular inhibitory tasks. PMID:26270470

  4. 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

  5. Evaluation and analysis of Seasat-A Scanning multichannel Microwave radiometer (SMMR) Antenna Pattern Correction (APC) algorithm. Sub-task 2: T sub B measured vs. T sub B calculated comparison results

    NASA Technical Reports Server (NTRS)

    Kitzis, J. L.; Kitzis, S. N.

    1979-01-01

    Interim Antenna Pattern Correction (APC) brightness temperature measurements for all ten SMMR channels are compared with calculated values generated from surface truth data. Plots and associated statistics are presented for the available points of coincidence between SMMR and surface truth measurements acquired for the Gulf of Alaska SEASAT Experiment. The most important conclusions of the study deal with the apparent existence of different instrument biases for each SMMR channel, and their variation across the scan.

  6. A synthesized heuristic task scheduling algorithm.

    PubMed

    Dai, Yanyan; Zhang, Xiangli

    2014-01-01

    Aiming at the static task scheduling problems in heterogeneous environment, a heuristic task scheduling algorithm named HCPPEFT is proposed. In task prioritizing phase, there are three levels of priority in the algorithm to choose task. First, the critical tasks have the highest priority, secondly the tasks with longer path to exit task will be selected, and then algorithm will choose tasks with less predecessors to schedule. In resource selection phase, the algorithm is selected task duplication to reduce the interresource communication cost, besides forecasting the impact of an assignment for all children of the current task permits better decisions to be made in selecting resources. The algorithm proposed is compared with STDH, PEFT, and HEFT algorithms through randomly generated graphs and sets of task graphs. The experimental results show that the new algorithm can achieve better scheduling performance.

  7. The Dissipating Task-Repetition Benefit in Cued Task Switching: Task-Set Decay or Temporal Distinctiveness?

    ERIC Educational Resources Information Center

    Horoufchin, Himeh; Philipp, Andrea M.; Koch, Iring

    2011-01-01

    Decay of task-set activation, as commonly assumed in models of task switching, has been thought to be indexed by manipulating the response-to-cue interval (RCI) in a task-cuing paradigm. We propose an alternative account for RCI effects suggesting that episodic task retrieval is modulated by temporal distinctiveness, which we define as the ratio…

  8. Cognitive and Physical Fatigue Tasks Enhance Pain, Cognitive Fatigue and Physical Fatigue in People with Fibromyalgia

    PubMed Central

    Dailey, Dana L; Keffala, Valerie J; Sluka, Kathleen A

    2014-01-01

    Objective Fibromyalgia is a condition characterized by chronic widespread muscle pain and fatigue. The primary objective of this study was to determine if pain, perceived cognitive fatigue, and perceived physical fatigue were enhanced in participants with fibromyalgia compared to healthy controls during a cognitive fatigue task, a physical fatigue task and a dual fatigue task. Methods Twenty four people with fibromyalgia and 33 healthy controls completed pain, fatigue and function measures. A cognitive fatigue task (Controlled Oral Word Association Test) and physical fatigue task (Valpar peg test) were done individually and combined for a dual fatigue task. Resting pain, perceived cognitive fatigue and perceived physical fatigue were assessed during each task using visual analogue scales. Function was assessed with shoulder range of motion and grip. Results People with fibromyalgia had significantly higher increases in pain, cognitive fatigue and physical fatigue when compared to healthy controls after completion of a cognitive fatigue task, a physical fatigue task, or a dual fatigue task (p<0.01). People with fibromyalgia performed equivalently on measures of physical performance and cognitive performance on the physical and cognitive fatigue tasks, respectively. Conclusions These data show that people with fibromyalgia show larger increases in pain, perceived cognitive fatigue and perceived physical fatigue to both cognitive and physical fatigue tasks compared to healthy controls. The increases in pain and fatigue during cognitive and physical fatigue tasks could influence subject participation in daily activities and rehabilitation. PMID:25074583

  9. Hybrid Scheduling Model for Independent Grid Tasks

    PubMed Central

    Shanthini, J.; Kalaikumaran, T.; Karthik, S.

    2015-01-01

    Grid computing facilitates the resource sharing through the administrative domains which are geographically distributed. Scheduling in a distributed heterogeneous environment is intrinsically very hard because of the heterogeneous nature of resource collection. Makespan and tardiness are two different measures of scheduling, and many of the previous researches concentrated much on reduction of makespan, which measures the machine utilization. In this paper, we propose a hybrid scheduling algorithm for scheduling independent grid tasks with the objective of reducing total weighted tardiness of grid tasks. Tardiness is to measure the due date performance, which has a direct impact on cost for executing the jobs. In this paper we propose BG_ATC algorithm which is a combination of best gap (BG) search and Apparent Tardiness Cost (ATC) indexing algorithm. Furthermore, we implemented these two algorithms in two different phases of the scheduling process. In addition to that, the comparison was made on results with various benchmark algorithms and the experimental results show that our algorithm outperforms the benchmark algorithms. PMID:26543897

  10. Hybrid Scheduling Model for Independent Grid Tasks.

    PubMed

    Shanthini, J; Kalaikumaran, T; Karthik, S

    2015-01-01

    Grid computing facilitates the resource sharing through the administrative domains which are geographically distributed. Scheduling in a distributed heterogeneous environment is intrinsically very hard because of the heterogeneous nature of resource collection. Makespan and tardiness are two different measures of scheduling, and many of the previous researches concentrated much on reduction of makespan, which measures the machine utilization. In this paper, we propose a hybrid scheduling algorithm for scheduling independent grid tasks with the objective of reducing total weighted tardiness of grid tasks. Tardiness is to measure the due date performance, which has a direct impact on cost for executing the jobs. In this paper we propose BG_ATC algorithm which is a combination of best gap (BG) search and Apparent Tardiness Cost (ATC) indexing algorithm. Furthermore, we implemented these two algorithms in two different phases of the scheduling process. In addition to that, the comparison was made on results with various benchmark algorithms and the experimental results show that our algorithm outperforms the benchmark algorithms. PMID:26543897

  11. Hybrid Scheduling Model for Independent Grid Tasks.

    PubMed

    Shanthini, J; Kalaikumaran, T; Karthik, S

    2015-01-01

    Grid computing facilitates the resource sharing through the administrative domains which are geographically distributed. Scheduling in a distributed heterogeneous environment is intrinsically very hard because of the heterogeneous nature of resource collection. Makespan and tardiness are two different measures of scheduling, and many of the previous researches concentrated much on reduction of makespan, which measures the machine utilization. In this paper, we propose a hybrid scheduling algorithm for scheduling independent grid tasks with the objective of reducing total weighted tardiness of grid tasks. Tardiness is to measure the due date performance, which has a direct impact on cost for executing the jobs. In this paper we propose BG_ATC algorithm which is a combination of best gap (BG) search and Apparent Tardiness Cost (ATC) indexing algorithm. Furthermore, we implemented these two algorithms in two different phases of the scheduling process. In addition to that, the comparison was made on results with various benchmark algorithms and the experimental results show that our algorithm outperforms the benchmark algorithms.

  12. An empirically derived figure of merit for the quality of overall task performance

    NASA Technical Reports Server (NTRS)

    Lemay, Moira

    1989-01-01

    The need to develop an operationally relevant figure of merit for the quality of performance of a complex system such as an aircraft cockpit stems from a hypothesized dissociation between measures of performance and those of workload. Performance can be measured in terms of time, errors, or a combination of these. In most tasks performed by expert operators, errors are relatively rare and often corrected in time to avoid consequences. Moreover, perfect performance is seldom necessary to accomplish a particular task. Moreover, how well an expert performs a complex task consisting of a series of discrete cognitive tasks superimposed on a continuous task, such as flying an aircraft, does not depend on how well each discrete task is performed, but on their smooth sequencing. This makes the amount of time spent on each subtask of paramount importance in measuring overall performance, since smooth sequencing requires a minimum amount of time spent on each task. Quality consists in getting tasks done within a crucial time interval while maintaining acceptable continuous task performance. Thus, a figure of merit for overall quality of performance should be primarily a measure of time to perform discrete subtasks combined with a measure of basic vehicle control. Thus, the proposed figure of merit requires doing a task analysis on a series of performance, or runs, of a particular task, listing each discrete task and its associated time, and calculating the mean and standard deviation of these times, along with the mean and standard deviation of tracking error for the whole task. A set of simulator data on 30 runs of a landing task was obtained and a figure of merit will be calculated for each run. The figure of merit will be compared for voice and data link, so that the impact of this technology on total crew performance (not just communication performance) can be assessed. The effect of data link communication on other cockpit tasks will also be considered.

  13. Oddball Cases of Fluid Mechanics: Cobwebs and Pharaohs

    ERIC Educational Resources Information Center

    Lafrance, Pierre

    1975-01-01

    Explains macroscopic properties of a number of systems as averaged-out behavior of numbers of particles. The approach is applied to a model of nuclear fission, rotational velocity in a galaxy, the nature of the rings of Saturn, oscillations of the earth, drops on a spider web, and the shape of ruined Meidum pyramid. (GH)

  14. [Psychological and stabilographic features in healthy persons performing dual tasks with different quality].

    PubMed

    2013-01-01

    The results of performance of 40 healthy volunteers (29.8 ± 2.47 y.o.) in four dual tasks that included postural balance task as a motor sub-task and calculation as a cognitive sub-task were compared to results of individual psychological assessment which measured working and spatial memory capacity, speed of attention switch etc. Performance of participants in dual tasks was not uniform. For each of four tasks four types of performance were observed. Those included decrease of performance in both or one task and increase of performance in both tasks. In one of the four dual tasks 30% of the group of participants performed in both components of dual task better then in separate motor and cognitive tasks. Better performance in this dual task correlated with higher speed of attention switch, higher estimates of spatial and working memory. Analysis of results of psychological and stabilografic investigations showed negative correlation between speed of sway of center of pressure (CoP) and speed of attention switch test, and also between amplitude of CoP sway along frontal axis and capacity of spatial and working memory. These correlations reflect involvement of cognitive resources in voluntary postural control and motor automatism in successful dual task performance. Selected variant of dual task could be used as an instrument of selection of individuals for activities related to high informational loads. PMID:25508959

  15. [Psychological and stabilographic features in healthy persons performing dual tasks with different quality].

    PubMed

    Zharikov, A V; Zhavoronkova, L A; Kuptsova, S B; Kushnir, E M; Kulikov, M A; Mikhalkova, A A

    2013-01-01

    The results of performance of 40 healthy volunteers (29.8 ± 2.47 y.o.) in four dual tasks that included postural balance task as a motor sub-task and calculation as a cognitive sub-task were compared to results of individual psychological assessment which measured working and spatial memory capacity, speed of attention switch etc. Performance of participants in dual tasks was not uniform. For each of four tasks four types of performance were observed. Those included decrease of performance in both or one task and increase of performance in both tasks. In one of the four dual tasks 30% of the group of participants performed in both components of dual task better then in separate motor and cognitive tasks. Better performance in this dual task correlated with higher speed of attention switch, higher estimates of spatial and working memory. Analysis of results of psychological and stabilografic investigations showed negative correlation between speed of sway of center of pressure (CoP) and speed of attention switch test, and also between amplitude of CoP sway along frontal axis and capacity of spatial and working memory. These correlations reflect involvement of cognitive resources in voluntary postural control and motor automatism in successful dual task performance. Selected variant of dual task could be used as an instrument of selection of individuals for activities related to high informational loads. PMID:25486828

  16. Combining Partial Directed Coherence and Graph Theory to Analyse Effective Brain Networks of Different Mental Tasks

    PubMed Central

    Huang, Dengfeng; Ren, Aifeng; Shang, Jing; Lei, Qiao; Zhang, Yun; Yin, Zhongliang; Li, Jun; von Deneen, Karen M.; Huang, Liyu

    2016-01-01

    Purpose: The aim of this study is to qualify the network properties of the brain networks between two different mental tasks (play task or rest task) in a healthy population. Methods and Materials: EEG signals were recorded from 19 healthy subjects when performing different mental tasks. Partial directed coherence (PDC) analysis, based on Granger causality (GC), was used to assess the effective brain networks during the different mental tasks. Moreover, the network measures, including degree, degree distribution, local and global efficiency in delta, theta, alpha, and beta rhythms were calculated and analyzed. Results: The local efficiency is higher in the beta frequency and lower in the theta frequency during play task whereas the global efficiency is higher in the theta frequency and lower in the beta frequency in the rest task. Significance: This study reveals the network measures during different mental states and efficiency measures may be used as characteristic quantities for improvement in attentional performance. PMID:27242495

  17. Task-Based Writing Instruction

    ERIC Educational Resources Information Center

    Bantis, Alexandros

    2010-01-01

    The purpose of this study was to investigate the impact of task-based writing instruction, a communicative language-teaching method, on second language acquisition and differentiation of instruction for English language learners during the independent work time instructional component of the Open Court Reading program. Through student-teacher…

  18. Dimensions of Organizational Task Environments.

    ERIC Educational Resources Information Center

    Dess, Gregory G.; Beard, Donald W.

    1984-01-01

    Reducing Aldrich's codification of organizational task environments from six to three dimensions--munificence (capacity), complexity (homogeneity-heterogeneity, concentration-dispersion), and dynamism (stability-instability, turbulence), the authors use interim and factor analytical techniques to explore each dimension's viability and draw…

  19. American Indian Task Force Report.

    ERIC Educational Resources Information Center

    Mackey, John E., Ed.

    Assuming that the client is central to any service program, the American Indian Task Force examined a national sample of "grass roots" social service organizations and/or individuals and schools of social work to determine the capability of providing relevant social work education to American Indians. Accordingly, the highest priorities…

  20. Tasks Ahead for Indian Education.

    ERIC Educational Resources Information Center

    Yadav, R. K.

    1980-01-01

    Reviews past accomplishments and remaining tasks in Indian education with particular emphasis on the production of technical and professional personnel to match the nation's labor needs and the spread of education to three previously disadvantaged groups: rural populations, women, and the scheduled castes and tribes. (SJL)