Effects of mora deletion, nonword repetition, rapid naming, and visual search performance on beginning reading in Japanese.

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Kobayashi, Maya Shiho; Haynes, Charles W; Macaruso, Paul; Hook, Pamela E; Kato, Junko

2005-06-01

This study examined the extent to which mora deletion (phonological analysis), nonword repetition (phonological memory), rapid automatized naming (RAN), and visual search abilities predict reading in Japanese kindergartners and first graders. Analogous abilities have been identified as important predictors of reading skills in alphabetic languages like English. In contrast to English, which is based on grapheme-phoneme relationships, the primary components of Japanese orthography are two syllabaries-hiragana and katakana (collectively termed "kana")-and a system of morphosyllabic symbols (kanji). Three RAN tasks (numbers, objects, syllabary symbols [hiragana]) were used with kindergartners, with an additional kanji RAN task included for first graders. Reading measures included accuracy and speed of passage reading for kindergartners and first graders, and reading comprehension for first graders. In kindergartners, hiragana RAN and number RAN were the only significant predictors of reading accuracy and speed. In first graders, kanji RAN and hiragana RAN predicted reading speed, whereas accuracy was predicted by mora deletion. Reading comprehension was predicted by kanji RAN, mora deletion, and nonword repetition. Although number RAN did not contribute unique variance to any reading measure, it correlated highly with kanji RAN. Implications of these findings for research and practice are discussed.

Non-word repetition in children with specific language impairment: a deficit in phonological working memory or in long-term verbal knowledge?

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Casalini, Claudia; Brizzolara, Daniela; Chilosi, Anna; Cipriani, Paola; Marcolini, Stefania; Pecini, Chiara; Roncoli, Silvia; Burani, Cristina

2007-08-01

In this study we investigated the effects of long-term memory (LTM) verbal knowledge on short-term memory (STM) verbal recall in a sample of Italian children affected by different subtypes of specific language impairment (SLI). The aim of the study was to evaluate if phonological working memory (PWM) abilities of SLI children can be supported by LTM linguistic representations and if PWM performances can be differently affected in the various subtypes of SLI. We tested a sample of 54 children affected by Mixed Receptive-Expressive (RE), Expressive (Ex) and Phonological (Ph) SLI (DSM-IV - American Psychiatric Association, 1994) by means of a repetition task of words (W) and non-words (NW) differing in morphemic structure [morphological non-words (MNW), consisting of combinations of roots and affixes - and simple non-words - with no morphological constituency]. We evaluated the effects of lexical and morpho-lexical LTM representations on STM recall by comparing the repetition accuracy across the three types of stimuli. Results indicated that although SLI children, as a group, showed lower repetition scores than controls, their performance was affected similarly to controls by the type of stimulus and the experimental manipulation of the non-words (better repetition of W than MNW and NW, and of MNW than NW), confirming the recourse to LTM verbal representations to support STM recall. The influence of LTM verbal knowledge on STM recall in SLI improved with age and did not differ among the three types of SLI. However, the three types of SLI differed in the accuracy of their repetition performances (PMW abilities), with the Phonological group showing the best scores. The implications for SLI theory and practice are discussed.

Nonword Repetition and Language Learning Disorders: A Developmental Contingency Framework

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Snowling, Margaret J.

2006-01-01

In 1990 Gathercole and Baddeley proposed a strong hypothesis that has generated a wealth of research in the field of language development and disorder. The hypothesis was that phonological memory, as indexed by nonword repetition, is causally related to vocabulary development. Support for the hypothesis came from an impressive range of…

Dissociating mere exposure and repetition priming as a function of word type.

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Butler, Laurie T; Berry, Dianne C; Helman, Shaun

2004-07-01

The mere exposure effect is defined as enhanced attitude toward a stimulus that has been repeatedly exposed. Repetition priming is defined as facilitated processing of a previously exposed stimulus. We conducted a direct comparison between the two phenomena to test the assumption that the mere exposure effect represents an example of repetition priming. In two experiments, having studied a set of words or nonwords, participants were given a repetition priming task (perceptual identification) or one of two mere exposure (affective liking or preference judgment) tasks. Repetition priming was obtained for both words and nonwords, but only nonwords produced a mere exposure effect. This demonstrates a key boundary for observing the mere exposure effect, one not readily accommodated by a perceptual representation systems (Tulving & Schacter, 1990) account, which assumes that both phenomena should show some sensitivity to nonwords and words.

A Quasi-Universal Nonword Repetition Task as a Diagnostic Tool for Bilingual Children Learning Dutch as a Second Language.

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Boerma, Tessel; Chiat, Shula; Leseman, Paul; Timmermeister, Mona; Wijnen, Frank; Blom, Elma

2015-12-01

This study evaluated a newly developed quasi-universal nonword repetition task (Q-U NWRT) as a diagnostic tool for bilingual children with language impairment (LI) who have Dutch as a 2nd language. The Q-U NWRT was designed to be minimally influenced by knowledge of 1 specific language in contrast to a language-specific NWRT with which it was compared. One hundred twenty monolingual and bilingual children with and without LI participated (30 per group). A mixed-design analysis of variance was used to investigate the effects of LI and bilingualism on the NWRTs. Receiver operating characteristic analyses were conducted to evaluate the instruments' diagnostic value. Large negative effects of LI were found on both NWRTs, whereas negative effects of bilingualism only occurred on the language-specific NWRT. Both instruments had high clinical accuracy in the monolingual group, but only the Q-U NWRT had high clinical accuracy in the bilingual group. This study indicates that the Q-U NWRT is a promising diagnostic tool to help identify LI in bilingual children learning Dutch as a 2nd language. The instrument was clinically accurate in both a monolingual and bilingual group of children and seems better able to disentangle LI from language disadvantage than more language-specific measures.

Phonological Working Memory for Words and Nonwords in Cerebral Cortex

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Perrachione, Tyler K.; Ghosh, Satrajit S.; Ostrovskaya, Irina; Gabrieli, John D. E.; Kovelman, Ioulia

2017-01-01

Purpose: The primary purpose of this study was to identify the brain bases of phonological working memory (the short-term maintenance of speech sounds) using behavioral tasks analogous to clinically sensitive assessments of nonword repetition. The secondary purpose of the study was to identify how individual differences in brain activation were…

Words are not enough: nonword repetition as an indicator of arcuate fasciculus integrity during brain tumor resection.

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Sierpowska, Joanna; Gabarrós, Andreu; Fernandez-Coello, Alejandro; Camins, Àngels; Castañer, Sara; Juncadella, Montserrat; Morís, Joaquín; Rodríguez-Fornells, Antoni

2017-02-01

OBJECTIVE Subcortical electrical stimulation during brain surgery may allow localization of functionally crucial white matter fibers and thus tailoring of the tumor resection according to its functional limits. The arcuate fasciculus (AF) is a white matter bundle connecting frontal, temporal, and parietal cortical areas that is often disrupted by left brain lesions. It plays a critical role in several cognitive functions related to phonological processing, but current intraoperative monitoring methods do not yet allow mapping of this tract with sufficient precision. In the present study the authors aimed to test a new paradigm for the intraoperative monitoring of the AF. METHODS In this report, the authors studied 12 patients undergoing awake brain surgery for tumor resection with a related risk of AF damage. To preserve AF integrity and the cognitive processes sustained by this tract in the intraoperative context, the authors used real word repetition (WR) and nonword repetition (NWR) tasks as complements to standard picture naming. RESULTS Compared with the errors identified by WR or picture naming, the NWR task allowed the detection of subtle errors possibly related to AF alterations. Moreover, only 3 patients demonstrated phonological paraphasias in standard picture naming, and in 2 of these patients the paraphasias co-occurred with the total loss of WR and NWR ability. Before surgery, lesion volume predicted a patient's NWR performance. CONCLUSIONS The authors suggest that monitoring NWR intraoperatively may complement the standard naming tasks and could permit better preservation of the important language production functions subserved by the AF.

Repetition and masked form priming within and between languages using word and nonword neighbors

OpenAIRE

Dijkstra, A.F.J.; Hilberink-Schulpen, B.J.H.; Heuven, W.J.B. van

2010-01-01

If access to the bilingual lexicon takes place in a language independent way, monolingual repetition and masked form, priming accounts should be directly applicable to bilinguals. We tested such an account (Grainger and Jacobs, 1999) and extended it to explain bilingual ejects from L2 to L1. Dutch English bilinguals made a lexical decision on a Dutch target word preceded by a briefly presented word or nonword prime from Dutch (L1; Exp. I) or English (L2; Exp. 2). The prime was an orthographic...

Nonword repetition in children with cochlear implants: a potential clinical marker of poor language acquisition.

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Nittrouer, Susan; Caldwell-Tarr, Amanda; Sansom, Emily; Twersky, Jill; Lowenstein, Joanna H

2014-11-01

Cochlear implants (CIs) can facilitate the acquisition of spoken language for deaf children, but challenges remain. Language skills dependent on phonological sensitivity are most at risk for these children, so having an effective way to diagnose problems at this level would be of value for school speech-language pathologists. The goal of this study was to assess whether a nonword repetition (NWR) task could serve that purpose. Participants were 104 second graders: 49 with normal hearing (NH) and 55 with CIs. In addition to NWR, children were tested on 10 measures involving phonological awareness and processing, serial recall of words, vocabulary, reading, and grammar. Children with CIs performed more poorly than children with NH on NWR, and sensitivity to phonological structure alone explained that performance for children in both groups. For children with CIs, 2 audiological factors positively influenced outcomes on NWR: being identified with hearing loss at a younger age and having experience with wearing a hearing aid on the unimplanted ear at the time of receiving a 1st CI. NWR scores were better able to rule out than to rule in such language deficits. Well-designed NWR tasks could have clinical utility in assessments of language acquisition for school-age children with CIs.

Preschool speech articulation and nonword repetition abilities may help predict eventual recovery or persistence of stuttering.

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Spencer, Caroline; Weber-Fox, Christine

2014-09-01

In preschool children, we investigated whether expressive and receptive language, phonological, articulatory, and/or verbal working memory proficiencies aid in predicting eventual recovery or persistence of stuttering. Participants included 65 children, including 25 children who do not stutter (CWNS) and 40 who stutter (CWS) recruited at age 3;9-5;8. At initial testing, participants were administered the Test of Auditory Comprehension of Language, 3rd edition (TACL-3), Structured Photographic Expressive Language Test, 3rd edition (SPELT-3), Bankson-Bernthal Test of Phonology-Consonant Inventory subtest (BBTOP-CI), Nonword Repetition Test (NRT; Dollaghan & Campbell, 1998), and Test of Auditory Perceptual Skills-Revised (TAPS-R) auditory number memory and auditory word memory subtests. Stuttering behaviors of CWS were assessed in subsequent years, forming groups whose stuttering eventually persisted (CWS-Per; n=19) or recovered (CWS-Rec; n=21). Proficiency scores in morphosyntactic skills, consonant production, verbal working memory for known words, and phonological working memory and speech production for novel nonwords obtained at the initial testing were analyzed for each group. CWS-Per were less proficient than CWNS and CWS-Rec in measures of consonant production (BBTOP-CI) and repetition of novel phonological sequences (NRT). In contrast, receptive language, expressive language, and verbal working memory abilities did not distinguish CWS-Rec from CWS-Per. Binary logistic regression analysis indicated that preschool BBTOP-CI scores and overall NRT proficiency significantly predicted future recovery status. Results suggest that phonological and speech articulation abilities in the preschool years should be considered with other predictive factors as part of a comprehensive risk assessment for the development of chronic stuttering. At the end of this activity the reader will be able to: (1) describe the current status of nonlinguistic and linguistic predictors for

Nonword Repetition: The Relative Contributions of Phonological Short-Term Memory and Phonological Representations in Children with Language and Reading Impairment

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Rispens, Judith; Baker, Anne

2012-01-01

Purpose: This study investigates the relative contributions of phonological short-term memory and phonological representations to nonword repetition (NWR). This was evaluated in children with specific language impairment (SLI) and/or reading impairment (RI); it was also studied from a developmental perspective by comparing 2 groups of typically…

Word Recognition and Nonword Repetition in Children with Language Disorders: The Effects of Neighborhood Density, Lexical Frequency, and Phonotactic Probability

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Rispens, Judith; Baker, Anne; Duinmeijer, Iris

2015-01-01

Purpose: The effects of neighborhood density (ND) and lexical frequency on word recognition and the effects of phonotactic probability (PP) on nonword repetition (NWR) were examined to gain insight into processing at the lexical and sublexical levels in typically developing (TD) children and children with developmental language problems. Method:…

Long-term repetition priming with symmetrical polygons and words.

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Kersteen-Tucker, Z

1991-01-01

In two different tasks, subjects were asked to make lexical decisions (word or nonword) and symmetry judgments (symmetrical or nonsymmetrical) about two-dimensional polygons. In both tasks, every stimulus was repeated at one of four lags (0, 1, 4, or 8 items interposed between the first and second stimulus presentations). This paradigm, known as repetition priming, revealed comparable short-term priming (Lag 0) and long-term priming (Lags 1, 4, and 8) both for symmetrical polygons and for words. A shorter term component (Lags 0 and 1) of priming was observed for nonwords, and only very short-term priming (Lag 0) was observed for nonsymmetrical polygons. These results indicate that response facilitation accruing from repeated exposure can be observed for stimuli that have no preexisting memory representations and suggest that perceptual factors contribute to repetition-priming effects.

Nonword repetition--a clinical marker for specific language impairment in Swedish associated with parents' language-related problems.

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Nelli Kalnak

Full Text Available First, we explore the performance of nonword repetition (NWR in children with specific language impairment (SLI and typically developing children (TD in order to investigate the accuracy of NWR as a clinical marker for SLI in Swedish-speaking school-age children. Second, we examine the relationship between NWR, family aggregation, and parental level of education in children with SLI. A sample of 61 children with SLI, and 86 children with TD, aged 8-12 years, were administered an NWR test. Family aggregation, measured as the prevalence of language and/or literacy problems (LLP in parents of the children with SLI, was based on family history interviews. The sensitivity and specificity of nonword repetition was analyzed in a binary logistic regression, cut-off values were established with ROC curves, and positive and negative likelihood ratios reported. Results from the present study show that NWR distinguishes well between Swedish-speaking school-children with and without SLI. We found 90.2% sensitivity and 97.7% specificity at a cut-off level of -2 standard deviations for binary scoring of nonwords. Differences between the SLI and TD groups showed large effect sizes for the two scoring measures binary (d = 2.11 and percent correct consonants (PCC (d = 1.79. The children with SLI were split into two subgroups: those with no parents affected with LLP (n = 12, and those with one or both parents affected (n = 49. The subgroup consisting of affected parents had a significantly lower score on NWR binary (p = .037, and there was a great difference between the subgroups (d = 0.7. When compared to the TD group, the difference from the subgroup with affected parents was almost one standard deviation larger (d = 2.47 than the difference from the TD to the subgroup consisting of non-affected parents (d = 1.57. Our study calls for further exploration of the complex interaction between family aggregation, language input, and

PRESCHOOL SPEECH ARTICULATION AND NONWORD REPETITION ABILITIES MAY HELP PREDICT EVENTUAL RECOVERY OR PERSISTENCE OF STUTTERING

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Spencer, Caroline; Weber-Fox, Christine

2014-01-01

Purpose In preschool children, we investigated whether expressive and receptive language, phonological, articulatory, and/or verbal working memory proficiencies aid in predicting eventual recovery or persistence of stuttering. Methods Participants included 65 children, including 25 children who do not stutter (CWNS) and 40 who stutter (CWS) recruited at age 3;9–5;8. At initial testing, participants were administered the Test of Auditory Comprehension of Language, 3rd edition (TACL-3), Structured Photographic Expressive Language Test, 3rd edition (SPELT-3), Bankson-Bernthal Test of Phonology-Consonant Inventory subtest (BBTOP-CI), Nonword Repetition Test (NRT; Dollaghan & Campbell, 1998), and Test of Auditory Perceptual Skills-Revised (TAPS-R) auditory number memory and auditory word memory subtests. Stuttering behaviors of CWS were assessed in subsequent years, forming groups whose stuttering eventually persisted (CWS-Per; n=19) or recovered (CWS-Rec; n=21). Proficiency scores in morphosyntactic skills, consonant production, verbal working memory for known words, and phonological working memory and speech production for novel nonwords obtained at the initial testing were analyzed for each group. Results CWS-Per were less proficient than CWNS and CWS-Rec in measures of consonant production (BBTOP-CI) and repetition of novel phonological sequences (NRT). In contrast, receptive language, expressive language, and verbal working memory abilities did not distinguish CWS-Rec from CWS-Per. Binary logistic regression analysis indicated that preschool BBTOP-CI scores and overall NRT proficiency significantly predicted future recovery status. Conclusion Results suggest that phonological and speech articulation abilities in the preschool years should be considered with other predictive factors as part of a comprehensive risk assessment for the development of chronic stuttering. PMID:25173455

Synergy Repetition Training versus Task Repetition Training in Acquiring New Skill.

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Patel, Vrajeshri; Craig, Jamie; Schumacher, Michelle; Burns, Martin K; Florescu, Ionut; Vinjamuri, Ramana

2017-01-01

Traditionally, repetitive practice of a task is used to learn a new skill, exhibiting as immediately improved performance. Research suggests, however, that a more experience-based rather than exposure-based training protocol may allow for better transference of the skill to related tasks. In synergy-based motor control theory, fundamental motor skills, such as hand grasping, are represented with a synergy subspace that captures essential motor patterns. In this study, we propose that motor-skill learning through synergy-based mechanisms may provide advantages over traditional task repetition learning. A new task was designed to highlight the range of motion and dexterity of the human hand. Two separate training strategies were tested in healthy subjects: task repetition training and synergy training versus a control. All three groups showed improvements when retested on the same task. When tested on a similar, but different set of tasks, only the synergy group showed improvements in accuracy (9.27% increase) compared to the repetition (3.24% decline) and control (3.22% decline) groups. A kinematic analysis revealed that although joint angular peak velocities decreased, timing benefits stemmed from the initial feed-forward portion of the task (reaction time). Accuracy improvements may have derived from general improved coordination among the four involved fingers. These preliminary results warrant further investigation of synergy-based motor training in healthy individuals, as well as in individuals undergoing hand-based rehabilitative therapy.

Diagnostic accuracy of repetition tasks for the identification of specific language impairment (SLI) in bilingual children: evidence from Russian and Hebrew.

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Armon-Lotem, Sharon; Meir, Natalia

2016-11-01

Previous research demonstrates that repetition tasks are valuable tools for diagnosing specific language impairment (SLI) in monolingual children in English and a variety of other languages, with non-word repetition (NWR) and sentence repetition (SRep) yielding high levels of sensitivity and specificity. Yet, only a few studies have addressed the diagnostic accuracy of repetition tasks in bilingual children, and most available research focuses on English-Spanish sequential bilinguals. To evaluate the efficacy of three repetition tasks (forward digit span (FWD), NWR and SRep) in order to distinguish mono- and bilingual children with and without SLI in Russian and Hebrew. A total of 230 mono- and bilingual children aged 5;5-6;8 participated in the study: 144 bilingual Russian-Hebrew-speaking children (27 with SLI); and 52 monolingual Hebrew-speaking children (14 with SLI) and 34 monolingual Russian-speaking children (14 with SLI). Parallel repetition tasks were designed in both Russian and Hebrew. Bilingual children were tested in both languages. The findings confirmed that NWR and SRep are valuable tools in distinguishing monolingual children with and without SLI in Russian and Hebrew, while the results for FWD were mixed. Yet, testing of bilingual children with the same tools using monolingual cut-off points resulted in inadequate diagnostic accuracy. We demonstrate, however, that the use of bilingual cut-off points yielded acceptable levels of diagnostic accuracy. The combination of SRep tasks in L1/Russian and L2/Hebrew yielded the highest overall accuracy (i.e., 94%), but even SRep alone in L2/Hebrew showed excellent levels of sensitivity (i.e., 100%) and specificity (i.e., 89%), reaching 91% of total diagnostic accuracy. The results are very promising for identifying SLI in bilingual children and for showing that testing in the majority language with bilingual cut-off points can provide an accurate classification. © 2016 Royal College of Speech and Language

Responding to Nonwords in the Lexical Decision Task: Insights from the English Lexicon Project

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Yap, Melvin J.; Sibley, Daragh E.; Balota, David A.; Ratcliff, Roger; Rueckl, Jay

2014-01-01

Researchers have extensively documented how various statistical properties of words (e.g., word-frequency) influence lexical processing. However, the impact of lexical variables on nonword decision-making performance is less clear. This gap is surprising, since a better specification of the mechanisms driving nonword responses may provide valuable insights into early lexical processes. In the present study, item-level and participant-level analyses were conducted on the trial-level lexical decision data for almost 37,000 nonwords in the English Lexicon Project in order to identify the influence of different psycholinguistic variables on nonword lexical decision performance, and to explore individual differences in how participants respond to nonwords. Item-level regression analyses reveal that nonword response time was positively correlated with number of letters, number of orthographic neighbors, number of affixes, and baseword number of syllables, and negatively correlated with Levenshtein orthographic distance and baseword frequency. Participant-level analyses also point to within- and between-session stability in nonword responses across distinct sets of items, and intriguingly reveal that higher vocabulary knowledge is associated with less sensitivity to some dimensions (e.g., number of letters) but more sensitivity to others (e.g., baseword frequency). The present findings provide well-specified and interesting new constraints for informing models of word recognition and lexical decision. PMID:25329078

Task Repetition Effects on L1 Use in EFL Child Task-Based Interaction

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Azkarai, Agurtzane; García Mayo, María del Pilar

2017-01-01

Research has shown that tasks provide second language (L2) learners with many opportunities to learn the L2. Task repetition has been claimed to benefit L2 learning since familiarity with procedure and/or content gives learners the chance to focus on more specific aspects of language. Most research on task repetition has focused on adult…

Manipulating the Characteristics of Words and Nonwords to Better Understand Word Learning

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Vitevitch, Michael S.

2006-01-01

The work of Susan Gathercole and others on nonword repetition has increased general interest in the relationship between memory and language, and has provided a fertile theoretical framework for researchers to explore how the language system makes use of the phonological loop, a component in Baddeley's (1986) working memory model. Gathercole…

Analogous selection processes in declarative and procedural working memory: N-2 list-repetition and task-repetition costs.

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Gade, Miriam; Souza, Alessandra S; Druey, Michel D; Oberauer, Klaus

2017-01-01

Working memory (WM) holds and manipulates representations for ongoing cognition. Oberauer (Psychology of Learning and Motivation, 51, 45-100, 2009) distinguishes between two analogous WM sub-systems: a declarative WM which handles the objects of thought, and a procedural WM which handles the representations of (cognitive) actions. Here, we assessed whether analogous effects are observed when participants switch between memory sets (declarative representations) and when they switch between task sets (procedural representations). One mechanism assumed to facilitate switching in procedural WM is the inhibition of previously used, but currently irrelevant task sets, as indexed by n-2 task-repetition costs (Mayr & Keele, Journal of Experimental Psychology: General, 129(1), 4-26, 2000). In this study we tested for an analogous effect in declarative WM. We assessed the evidence for n-2 list-repetition costs across eight experiments in which participants switched between memory lists to perform speeded classifications, mental arithmetic, or a local recognition test. N-2 list-repetition costs were obtained consistently in conditions assumed to increase interference between memory lists, and when lists formed chunks in long-term memory. Further analyses across experiments revealed a substantial contribution of episodic memory to n-2 list-repetition costs, thereby questioning the interpretation of n-2 repetition costs as reflecting inhibition. We reanalyzed the data of eight task-switching experiments, and observed that episodic memory also contributes to n-2 task-repetition costs. Taken together, these results show analogous processing principles in declarative and procedural WM, and question the relevance of inhibitory processes for efficient switching between mental sets.

The Effect of "Massed" Task Repetitions on Complexity, Accuracy and Fluency: Does It Transfer to a New Task?

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Ahmadian, Mohammad Javad

2011-01-01

To date, research results suggest that task repetition positively affects oral task performance. However, researchers have not yet shown the extension of the benefits of repeating the same task to performance of a new task. This article first provides an overview of the currently available research findings on task repetition and then presents the…

Study on cerebral activation areas during repetition with functional MRI in normal adults

International Nuclear Information System (INIS)

Koseki, Yohju

2009-01-01

For cerebral activation of speech areas in functional MRI (f-MRI) study, the usefulness of an optical microphone, which made it possible to perform task repetition at real time during scanning, was examined. Subjects were 25 healthy adults (mean age, 27.1±5.6 years), who consisted of 15 right-handed and 10 left-handed or ambidextrous persons. Tasks comprised repetition of monosyllables, non-words, words and sentences. The repetition tasks were covertly performed during scanning of f-MRI by using an optical microphone. In both the right-handed and non-right-handed groups, activations in the left superior temporal gyrus (sensory speech area) were most frequently observed during all of the tasks. In the right-handed group, activations in the left inferior frontal (motor speech area) and superior temporal gyri were significantly more often observed than those in the right inferior frontal and superior temporal gyri. From an assessment of the laterality index (LI), left-side dominant activation was frequently seen in most of the cerebral regions including sensory and motor speech areas, although right-side and bilateral dominant activations were observed in a few cases. In both groups, activations in regions associated with sensory speech were significantly more often seen than those in regions associated with motor speech. The present predominant activations in regions involved in sensory speech indicate that the optical microphone is useful in f-MRI studies using task repetition. (author)

Comparison of Nonword Repetition Ability of Stuttering and Nonstuttering 5-8 Years Old Children: A Reviw on Covert Repair Hypothesis

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Mehdi Bakhtiar

2007-01-01

Full Text Available Objective: The goal of this research is to attest Covert Repair Hypothesis (CRH i.e, discovering the phonological loop of the word production process in stuttering children. Materials & Methods: In this analytical (Case – Control research, forty bisyllabic and trisyllabic nonwords were designed. After the pilot study, these nonwords were presented to twelve stuttering children with the ages 5-8 and twelve nonstuttering children by the use of DMDX software. Children were asked to repeat the nonwords immediately after hearing them, the reaction time were recorded by the DMDX. The number of phonological errors and correct responses were determined. Results: Findings proved that stuttering children in all its forms except of reaction time of trisyllabic nonwords had a weak performance. However, the research results were not statistically significant. Conclusion: The study evidences show differences between stuttering and nonstuttering children performances. This may outline the possible of defect in language processes of stuttering children, especially in phonological encoding of word production mechanism. Also, the difference pattern between groups had coordination with CRH assumptions.

Repetition and brain potentials when recognizing natural scenes: task and emotion differences

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Bradley, Margaret M.; Codispoti, Maurizio; Karlsson, Marie; Lang, Peter J.

2013-01-01

Repetition has long been known to facilitate memory performance, but its effects on event-related potentials (ERPs), measured as an index of recognition memory, are less well characterized. In Experiment 1, effects of both massed and distributed repetition on old–new ERPs were assessed during an immediate recognition test that followed incidental encoding of natural scenes that also varied in emotionality. Distributed repetition at encoding enhanced both memory performance and the amplitude of an old–new ERP difference over centro-parietal sensors. To assess whether these repetition effects reflect encoding or retrieval differences, the recognition task was replaced with passive viewing of old and new pictures in Experiment 2. In the absence of an explicit recognition task, ERPs were completely unaffected by repetition at encoding, and only emotional pictures prompted a modestly enhanced old–new difference. Taken together, the data suggest that repetition facilitates retrieval processes and that, in the absence of an explicit recognition task, differences in old–new ERPs are only apparent for affective cues. PMID:22842817

Short-Term Memory Performance in 7- and 8-Year-Old Children: The Relationship between Phonological and Pitch Processing

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Flagge, Ashley Gaal; Estis, Julie M.; Moore, Robert E.

2016-01-01

Purpose: The relationship between short-term memory for phonology and pitch was explored by examining accuracy scores for typically developing children for 5 experimental tasks: immediate nonword repetition (NWR), nonword repetition with an 8-s silent interference (NWRS), pitch discrimination (PD), pitch discrimination with an 8-s silent…

Task type and incidental L2 vocabulary learning: Repetition versus ...

African Journals Online (AJOL)

This study investigated the effect of task type on incidental L2 vocabulary learning. The different tasks investigated in this study differed in terms of repetition of encounters and task involvement load. In a within-subjects design, 72 Iranian learners of English practised 18 target words in three exercise conditions: three ...

Functional Anatomy of Recognition of Chinese Multi-Character Words: Convergent Evidence from Effects of Transposable Nonwords, Lexicality, and Word Frequency.

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Lin, Nan; Yu, Xi; Zhao, Ying; Zhang, Mingxia

2016-01-01

This fMRI study aimed to identify the neural mechanisms underlying the recognition of Chinese multi-character words by partialling out the confounding effect of reaction time (RT). For this purpose, a special type of nonword-transposable nonword-was created by reversing the character orders of real words. These nonwords were included in a lexical decision task along with regular (non-transposable) nonwords and real words. Through conjunction analysis on the contrasts of transposable nonwords versus regular nonwords and words versus regular nonwords, the confounding effect of RT was eliminated, and the regions involved in word recognition were reliably identified. The word-frequency effect was also examined in emerged regions to further assess their functional roles in word processing. Results showed significant conjunctional effect and positive word-frequency effect in the bilateral inferior parietal lobules and posterior cingulate cortex, whereas only conjunctional effect was found in the anterior cingulate cortex. The roles of these brain regions in recognition of Chinese multi-character words were discussed.

Encoding: the keystone to efficient functioning of verbal short-term memory.

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Barry, Johanna G; Sabisch, Beate; Friederici, Angela D; Brauer, Jens

2011-11-01

Verbal short-term memory (VSTM) is thought to play a critical role in language learning. It is indexed by the nonword repetition task where listeners are asked to repeat meaningless words like 'blonterstaping'. The present study investigated the effect on nonword repetition performance of differences in efficiency of functioning of some part of the neural architecture mediating VSTM. Hypotheses were stated within Baddeley and Hitch's (1974) multicomponent model of VSTM, with respect to regions of the brain known to be active during tasks tapping into VSTM. We were specifically interested in activations associated with the posterior planum temporale (Spt) which emerge during rehearsal since this region is hypothesized to be central to VTSM (Buchsbaum, Olsen, Koch, & Berman, 2005a). Participants performed a delayed reaction time task in the scanner which explicitly mimicked the three main stages of information-processing involved in VSTM (encoding, rehearsal, recall (here recognition)). The data for each stage were then convolved with scores from a separately measured nonword repetition task. Rather than observing a pattern of individual differences located to specific regions specialized for supporting VSTM, a dissociation in direction of correlation in overlapping regions of the brain was observed during encoding and recognition. Larger hemodynamic responses during encoding were associated with better nonword repetition, and vice versa during recognition. There was little evidence for a network of activations specialized for VSTM. Instead, the main correlations were observed in regions also known to be involved in long-term memory. It seems that individuals who are better at nonword repetition and hence at language learning, activate these regions more efficiently than poorer nonword-repeaters early after stimulus input. These observations are discussed with respect to various models proposed for explaining the phenomenon of VSTM. Crown Copyright © 2011

Differential preparation intervals modulate repetition processes in task switching: an ERP study

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Min eWang

2016-02-01

Full Text Available In task-switching paradigms, reaction times (RTs switch cost (SC and the neural correlates underlying the SC are affected by different preparation intervals. However, little is known about the effect of the preparation interval on the repetition processes in task-switching. To examine this effect we utilized a cued task-switching paradigm with long sequences of repeated trials. Response-stimulus intervals (RSI and cue-stimulus intervals (CSI were manipulated in short and long conditions. Electroencephalography (EEG and behavioral data were recorded. We found that with increasing repetitions, RTs were faster in the short CSI conditions, while P3 amplitudes decreased in the LS (long RSI and short CSI conditions. Positive correlations between RT benefit and P3 activation decrease (repeat 1 minus repeat 5, and between the slope of the RT and P3 regression lines were observed only in the LS condition. Our findings suggest that differential preparation intervals modulate repetition processes in task switching.

Word, nonword and visual paired associate learning in Dutch dyslexic children

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Messbauer, V.C.S.; de Jong, P.F.

2003-01-01

Verbal and non-verbal learning were investigated in 21 8-11-year-old dyslexic children and chronological-age controls, and in 21 7-9-year-old reading-age controls. Tasks involved the paired associate learning of words, nonwords, or symbols with pictures. Both learning and retention of associations

Exploring the repetition bias in voluntary task switching.

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Mittelstädt, Victor; Dignath, David; Schmidt-Ott, Magdalena; Kiesel, Andrea

2018-01-01

In the voluntary task-switching paradigm, participants are required to randomly select tasks. We reasoned that the consistent finding of a repetition bias (i.e., participants repeat tasks more often than expected by chance) reflects reasonable adaptive task selection behavior to balance the goal of random task selection with the goals to minimize the time and effort for task performance. We conducted two experiments in which participants were provided with variable amount of preview for the non-chosen task stimuli (i.e., potential switch stimuli). We assumed that switch stimuli would initiate some pre-processing resulting in improved performance in switch trials. Results showed that reduced switch costs due to extra-preview in advance of each trial were accompanied by more task switches. This finding is in line with the characteristics of rational adaptive behavior. However, participants were not biased to switch tasks more often than chance despite large switch benefits. We suggest that participants might avoid effortful additional control processes that modulate the effects of preview on task performance and task choice.

Making Things Difficult in Lexical Decision: The Impact of Pseudohomophones and Transposed-Letter Nonwords on Frequency and Semantic Priming Effects

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Lupker, Stephen J.; Pexman, Penny M.

2010-01-01

Performance in a lexical decision task is crucially dependent on the difficulty of the word-nonword discrimination. More wordlike nonwords cause not only a latency increase for words but also, as reported by Stone and Van Orden (1993), larger word frequency effects. Several current models of lexical decision making can explain these types of…

Writing nonsense: the interaction between lexical and sublexical knowledge in the priming of nonword spelling.

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Martin, Daisy H; Barry, Christopher

2012-08-01

The task of spelling nonwords to dictation necessarily requires the operation of a sublexical or assembled sound-to-spelling conversion process. We report an experiment that shows a clear lexical priming effect on nonword spelling (e.g., /vi:m/ was spelled as VEME more often following the prime word "theme" and as VEAM more often following "dream"), which was larger for lexically low-probability (or low-contingency) than for common (or high-contingency) spellings. Priming diminished when an unrelated word intervened between the prime word and target nonword and did so more for the production of low- than for high-contingency spellings. We interpret these results within an interactive model of spelling production that proposes feedback from the graphemic level to both the lexical and assembled spelling processes.

Acoustic and Perceptual Correlates of Stress in Nonwords Produced by Children with Suspected Developmental Apraxia of Speech and Children with Phonological Disorder.

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Munson, Benjamin; Bjorum, Elissa M.; Windsor, Jennifer

2003-01-01

This study examined whether accuracy in producing linguistic stress reliably distinguished between five children with suspected developmental apraxia of speech (sDAS) and five children with phonological disorder (PD). No group differences in the production of stress were found; however, listeners judged that nonword repetitions of the children…

English Language Learners' Nonword Repetition Performance: The Influence of Age, L2 Vocabulary Size, Length of L2 Exposure, and L1 Phonology.

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Duncan, Tamara Sorenson; Paradis, Johanne

2016-02-01

This study examined individual differences in English language learners' (ELLs) nonword repetition (NWR) accuracy, focusing on the effects of age, English vocabulary size, length of exposure to English, and first-language (L1) phonology. Participants were 75 typically developing ELLs (mean age 5;8 [years;months]) whose exposure to English began on average at age 4;4. Children spoke either a Chinese language or South Asian language as an L1 and were given English standardized tests for NWR and receptive vocabulary. Although the majority of ELLs scored within or above the monolingual normal range (71%), 29% scored below. Mixed logistic regression modeling revealed that a larger English vocabulary, longer English exposure, South Asian L1, and older age all had significant and positive effects on ELLs' NWR accuracy. Error analyses revealed the following L1 effect: onset consonants were produced more accurately than codas overall, but this effect was stronger for the Chinese group whose L1s have a more limited coda inventory compared with English. ELLs' NWR performance is influenced by a number of factors. Consideration of these factors is important in deciding whether monolingual norm referencing is appropriate for ELL children.

Effects of Immediate Repetition in L2 Speaking Tasks: A Focused Study

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Bei, Gavin Xiaoyue

2013-01-01

This paper reports on a focused investigation into the immediate effects of oral narrative task repetition by two adult EFL learners of intermediate and high proficiency. Two participants performed a narrative speaking task after watching a cartoon video clip and repeated their performance three times, followed by a retrospective report in an…

Category Priming in the Lexical Decision Task and Evidence of Repetition Effects.

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Sanza, James

Semantic priming is the process by which a subject performing a lexical decision task is prepared for a target word through the presentation of a semantically related word. Repetition of a given word at specific intervals is one form of priming that has been shown to reduce subject reaction time in word recognition tasks. A study was conducted to…

Speech Perception and Phonological Short-Term Memory Capacity in Language Impairment: Preliminary Evidence from Adolescents with Specific Language Impairment (SLI) and Autism Spectrum Disorders (ASD)

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Loucas, Tom; Riches, Nick Greatorex; Charman, Tony; Pickles, Andrew; Simonoff, Emily; Chandler, Susie; Baird, Gillian

2010-01-01

Background: The cognitive bases of language impairment in specific language impairment (SLI) and autism spectrum disorders (ASD) were investigated in a novel non-word comparison task which manipulated phonological short-term memory (PSTM) and speech perception, both implicated in poor non-word repetition. Aims: This study aimed to investigate the…

Effects of Task Repetition on Learners' Attention Orientation in L2 Oral Production

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Fukuta, Junya

2016-01-01

Task repetition facilitates learners' performance, at least temporarily: Since learners are already familiar with the content of the task at the initial enactment, they are capable of focusing their attention on linguistic form during the following enactment. However, the analysis in previous studies treated various aspects of "form" as…

The Effect of Task Instructions on Students' Use of Repetition in Argumentative Discourse

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Gilabert, Sandra; Garcia-Mila, Merce; Felton, Mark K.

2013-11-01

The reasoning belief of argumentum ad nauseam assumes that when someone repeats something often enough, he or she becomes more convincing. The present paper analyses the use of this strategy by seventh-grade students in an argumentation task. Sixty-five students (mean age: 12.2, SD = 0.4) from a public school in a mid-sized urban environment took part in the study. The students were asked to either argue to convince an opposing partner or argue to reach consensus with an opposing partner on three dilemmas that dealt with energy sources. Data were gathered according to a between-groups design that included one independent variable (argumentative goal: to convince vs. to reach consensus) and one dependent variable (the degree of argumentative repetitions). We predicted that in the condition to convince their partner, the students would use the repetition strategy more often in their attempts to be persuasive. Our findings show that the mean number of argumentative repetitions was significantly higher for the persuasion group for both of the most frequent argumentative structures (claim and claim data). The mean percentage of repeated claims for the persuasion condition was 86.2 vs. 69.0 for the consensus condition. For the claim data, the mean percentage for the persuasion group was 35.2 vs. 24.3 for the consensus group. Also, students in the persuasion group tended to repeat one idea many times rather than repeating many ideas a few times within the same argumentative structure. The results of our study support the hypothesis that the goal of the argumentative task mediates argumentative discourse and, more concretely, the rate of repetitions and the conceptual diversity of the statements. These differences in rates of repetition and conceptual diversity are related to the amount of learning produced by the instructional goal. We apply Mercer's idea that not all classroom argumentation tasks promote learning equally.

How African American English-Speaking First Graders Segment and Rhyme Words and Nonwords With Final Consonant Clusters.

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Shollenbarger, Amy J; Robinson, Gregory C; Taran, Valentina; Choi, Seo-Eun

2017-10-05

This study explored how typically developing 1st grade African American English (AAE) speakers differ from mainstream American English (MAE) speakers in the completion of 2 common phonological awareness tasks (rhyming and phoneme segmentation) when the stimulus items were consonant-vowel-consonant-consonant (CVCC) words and nonwords. Forty-nine 1st graders met criteria for 2 dialect groups: AAE and MAE. Three conditions were tested in each rhyme and segmentation task: Real Words No Model, Real Words With a Model, and Nonwords With a Model. The AAE group had significantly more responses that rhymed CVCC words with consonant-vowel-consonant words and segmented CVCC words as consonant-vowel-consonant than the MAE group across all experimental conditions. In the rhyming task, the presence of a model in the real word condition elicited more reduced final cluster responses for both groups. In the segmentation task, the MAE group was at ceiling, so only the AAE group changed across the different stimulus presentations and reduced the final cluster less often when given a model. Rhyming and phoneme segmentation performance can be influenced by a child's dialect when CVCC words are used.

Shoulder muscle fatigue during repetitive tasks as measured by electromyography and near-infrared spectroscopy.

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Ferguson, Sue A; Allread, W Gary; Le, Peter; Rose, Joseph; Marras, William S

2013-12-01

The objective of this study was to quantify shoulder muscle fatigue during repetitive exertions similar to motions found in automobile assembly tasks. Shoulder musculoskeletal disorders (MSDs) are a common and costly problem in automotive manufacturing. Ten subjects participated in the study. There were three independent variables: shoulder angle, frequency, and force. There were two types of dependent measures: percentage change in near-infrared spectroscopy (NIRS) measures and change in electromyography (EMG) median frequency. The anterior deltoid and trapezius muscles were measured for both NIRS and EMG. Also, EMG was collected on the middle deltoid and biceps muscles. The results showed that oxygenated hemoglobin decreased significantly due to the main effects (shoulder angle, frequency, and force). The percentage change in oxygenated hemoglobin had a significant interaction attributable to force and repetition for the anterior deltoid muscle, indicating that as repetition increased, the magnitude of the differences between the forces increased. The interaction of repetition and shoulder angle was also significant for the percentage change in oxygenated hemoglobin. The median frequency decreased significantly for the main effects; however, no interactions were statistically significant. There was significant shoulder muscle fatigue as a function of shoulder angle, task frequency, and force level. Furthermore, percentage change in oxygenated hemoglobin had two statistically significant interactions, enhancing our understanding of these risk factors. Ergonomists should examine interactions of force and repetition as well as shoulder angle and repetition when evaluating the risk of shoulder MSDs.

Stress Priming and Statistical Learning in Italian Nonword Reading: Evidence from Children

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Colombo, Lucia; Deguchi, Chizuru; Boureux, Magali

2014-01-01

Italian has regular spelling-sound correspondences; however, assignment of lexical stress is unpredictable. Sensitivity to stress neighborhood information was investigated by constructing three types of three-syllabic nonwords: nonwords with word-endings characterized by a strong neighborhood of dominant stress words (dominant), nonwords with…

Performance of repetitive tasks induces decreased grip strength and increased fibrogenic proteins in skeletal muscle: role of force and inflammation.

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Samir M Abdelmagid

Full Text Available This study elucidates exposure-response relationships between performance of repetitive tasks, grip strength declines, and fibrogenic-related protein changes in muscles, and their link to inflammation. Specifically, we examined forearm flexor digitorum muscles for changes in connective tissue growth factor (CTGF; a matrix protein associated with fibrosis, collagen type I (Col1; a matrix component, and transforming growth factor beta 1 (TGFB1; an upstream modulator of CTGF and collagen, in rats performing one of two repetitive tasks, with or without anti-inflammatory drugs.To examine the roles of force versus repetition, rats performed either a high repetition negligible force food retrieval task (HRNF, or a high repetition high force handle-pulling task (HRHF, for up to 9 weeks, with results compared to trained only (TR-NF or TR-HF and normal control rats. Grip strength declined with both tasks, with the greatest declines in 9-week HRHF rats. Quantitative PCR (qPCR analyses of HRNF muscles showed increased expression of Col1 in weeks 3-9, and CTGF in weeks 6 and 9. Immunohistochemistry confirmed PCR results, and also showed greater increases of CTGF and collagen matrix in 9-week HRHF rats than 9-week HRNF rats. ELISA, and immunohistochemistry revealed greater increases of TGFB1 in TR-HF and 6-week HRHF, compared to 6-week HRNF rats. To examine the role of inflammation, results from 6-week HRHF rats were compared to rats receiving ibuprofen or anti-TNF-α treatment in HRHF weeks 4-6. Both treatments attenuated HRHF-induced increases in CTGF and fibrosis by 6 weeks of task performance. Ibuprofen attenuated TGFB1 increases and grip strength declines, matching our prior results with anti-TNFα.Performance of highly repetitive tasks was associated with force-dependent declines in grip strength and increased fibrogenic-related proteins in flexor digitorum muscles. These changes were attenuated, at least short-term, by anti-inflammatory treatments.

Dissociated repetition deficits in aphasia can reflect flexible interactions between left dorsal and ventral streams and gender-dimorphic architecture of the right dorsal stream.

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Berthier, Marcelo L; Froudist Walsh, Seán; Dávila, Guadalupe; Nabrozidis, Alejandro; Juárez Y Ruiz de Mier, Rocío; Gutiérrez, Antonio; De-Torres, Irene; Ruiz-Cruces, Rafael; Alfaro, Francisco; García-Casares, Natalia

2013-01-01

Assessment of brain-damaged subjects presenting with dissociated repetition deficits after selective injury to either the left dorsal or ventral auditory pathways can provide further insight on their respective roles in verbal repetition. We evaluated repetition performance and its neural correlates using multimodal imaging (anatomical MRI, DTI, fMRI, and(18)FDG-PET) in a female patient with transcortical motor aphasia (TCMA) and in a male patient with conduction aphasia (CA) who had small contiguous but non-overlapping left perisylvian infarctions. Repetition in the TCMA patient was fully preserved except for a mild impairment in nonwords and digits, whereas the CA patient had impaired repetition of nonwords, digits and word triplet lists. Sentence repetition was impaired, but he repeated novel sentences significantly better than clichés. The TCMA patient had tissue damage and reduced metabolism in the left sensorimotor cortex and insula. DTI showed damage to the left temporo-frontal and parieto-frontal segments of the arcuate fasciculus (AF) and part of the left ventral stream together with well-developed right dorsal and ventral streams, as has been reported in more than one-third of females. The CA patient had tissue damage and reduced metabolic activity in the left temporoparietal cortex with additional metabolic decrements in the left frontal lobe. DTI showed damage to the left temporo-parietal and temporo-frontal segments of the AF, but the ventral stream was spared. The direct segment of the AF in the right hemisphere was also absent with only vestigial remains of the other dorsal subcomponents present, as is often found in males. fMRI during word and nonword repetition revealed bilateral perisylvian activation in the TCMA patient suggesting recruitment of spared segments of the left dorsal stream and right dorsal stream with propagation of signals to temporal lobe structures suggesting a compensatory reallocation of resources via the ventral streams. The

The Effects of Simultaneous Use of Careful Online Planning and Task Repetition on Accuracy, Complexity, and Fluency in EFL Learners' Oral Production

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Ahmadian, Mohammad Javad; Tavakoli, Mansoor

2011-01-01

This article reports on a study that was primarily aimed at investigating the effects of simultaneous use of careful online planning and task repetition on accuracy, complexity, and fluency in the oral production of learners of English as a foreign language (EFL). The effects of four planning and task repetition conditions (i.e. careful online…

Visualizing stressful aspects of repetitive motion tasks and opportunities for ergonomic improvements using computer vision.

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Greene, Runyu L; Azari, David P; Hu, Yu Hen; Radwin, Robert G

2017-11-01

Patterns of physical stress exposure are often difficult to measure, and the metrics of variation and techniques for identifying them is underdeveloped in the practice of occupational ergonomics. Computer vision has previously been used for evaluating repetitive motion tasks for hand activity level (HAL) utilizing conventional 2D videos. The approach was made practical by relaxing the need for high precision, and by adopting a semi-automatic approach for measuring spatiotemporal characteristics of the repetitive task. In this paper, a new method for visualizing task factors, using this computer vision approach, is demonstrated. After videos are made, the analyst selects a region of interest on the hand to track and the hand location and its associated kinematics are measured for every frame. The visualization method spatially deconstructs and displays the frequency, speed and duty cycle components of tasks that are part of the threshold limit value for hand activity for the purpose of identifying patterns of exposure associated with the specific job factors, as well as for suggesting task improvements. The localized variables are plotted as a heat map superimposed over the video, and displayed in the context of the task being performed. Based on the intensity of the specific variables used to calculate HAL, we can determine which task factors most contribute to HAL, and readily identify those work elements in the task that contribute more to increased risk for an injury. Work simulations and actual industrial examples are described. This method should help practitioners more readily measure and interpret temporal exposure patterns and identify potential task improvements. Copyright © 2017. Published by Elsevier Ltd.

Effects of activity repetition training with Salat (prayer) versus task oriented training on functional outcomes of stroke.

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Ghous, Misbah; Malik, Arshad Nawaz; Amjad, Mian Imran; Kanwal, Maria

2017-07-01

Stroke is one of most disabling condition which directly affects quality of life. The objective of this study was to compare the effect of activity repetition training with salat (prayer) versus task oriented training on functional outcomes of stroke. The study design was randomized control trial and 32 patients were randomly assigned into two groups'. The stroke including infarction or haemorrhagic, age bracket 30-70 years was included. The demographics were recorded and standardized assessment tool included Berg Balance Scale (BBS), Motor assessment scale (MAS) and Time Up and Go Test (TUG). The measurements were obtained at baseline, after four and six weeks. The mean age of the patients was 54.44±10.59 years with 16 (59%) male and 11(41%) female patients. Activity Repetition Training group showed significant improvement (peffective in enhancing the functional status as compare to task oriented training group. The repetition with motivation and concentration is the key in re-learning process of neural plasticity.

The effects of limited bandwidth and noise on verbal processing time and word recall in normal-hearing children.

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McCreery, Ryan W; Stelmachowicz, Patricia G

2013-09-01

Understanding speech in acoustically degraded environments can place significant cognitive demands on school-age children who are developing the cognitive and linguistic skills needed to support this process. Previous studies suggest the speech understanding, word learning, and academic performance can be negatively impacted by background noise, but the effect of limited audibility on cognitive processes in children has not been directly studied. The aim of the present study was to evaluate the impact of limited audibility on speech understanding and working memory tasks in school-age children with normal hearing. Seventeen children with normal hearing between 6 and 12 years of age participated in the present study. Repetition of nonword consonant-vowel-consonant stimuli was measured under conditions with combinations of two different signal to noise ratios (SNRs; 3 and 9 dB) and two low-pass filter settings (3.2 and 5.6 kHz). Verbal processing time was calculated based on the time from the onset of the stimulus to the onset of the child's response. Monosyllabic word repetition and recall were also measured in conditions with a full bandwidth and 5.6 kHz low-pass cutoff. Nonword repetition scores decreased as audibility decreased. Verbal processing time increased as audibility decreased, consistent with predictions based on increased listening effort. Although monosyllabic word repetition did not vary between the full bandwidth and 5.6 kHz low-pass filter condition, recall was significantly poorer in the condition with limited bandwidth (low pass at 5.6 kHz). Age and expressive language scores predicted performance on word recall tasks, but did not predict nonword repetition accuracy or verbal processing time. Decreased audibility was associated with reduced accuracy for nonword repetition and increased verbal processing time in children with normal hearing. Deficits in free recall were observed even under conditions where word repetition was not affected

Effects of Ease-of-Pronunciation on Non-Word Memory and Product Judgments

DEFF Research Database (Denmark)

Erz, Antonia; Christensen, Bo

The ease or difficulty of pronunciation can affect judgments. We experimentally show that linguistic fluency has a direct effect on liking and a U-shaped effect on memory of non-words. We further demonstrate that the fluency of novel, fictitious non-word brand names affects novelty and performance...

[Effect of divided attention on explicit and implicit aspects of recall].

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Wippich, W; Schmitt, R; Mecklenbräuker, S

1989-01-01

If subjects have to form word images before spelling a word from the image, results of a repetition of the spelling test reveal a reliable priming effect: Old words can be spelled faster than comparable control words, reflecting a form of implicit memory. We investigated whether this kind of repetition priming remains stable under conditions of divided attention in the study phase. The subjects had to spell meaningful words, meaningless non-words, and non-words that were meaningful with a backward spelling direction (troper, for example). In the testing stage, recognition judgments as a form of explicit memory were required, too. Divided attention in the study phase had a negative effect on explicit memory, as revealed by performance on the recognition task, but had little effect on implicit memory, as revealed by performance on the repetition of the spelling test. A further dissociation between implicit and explicit memory showed up as meaningful words were recognized much better than non-words, whereas implicit memory was uninfluenced by the meaningfulness variable. The disadvantage of backward spellings was not reduced with non-words (like troper) spelled backwards. Finally, we analyzed the relations between spelling times and recognition judgments and found a pattern of dependency for non-words only. Generally, the results are discussed within processing-oriented approaches to implicit memory with a special emphasis on controversial findings concerning the role of attention in different expressions of memory.

Subject-Verb Agreement and Verbal Short-Term Memory: A Perspective from Greek Children with Specific Language Impairment

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Lalioti, Marina; Stavrakaki, Stavroula; Manouilidou, Christina; Talli, Ioanna

2016-01-01

This study investigated the performance of school age Greek-speaking children with SLI on verbal short-term memory (VSTM) and Subject-Verb (S-V) agreement in comparison to chronological age controls and younger typically developing children. VSTM abilities were assessed by means of a non-word repetition task (NRT) and an elicited production task,…

Psychophysical Estimates of Frequency Discrimination: More than Just Limitations of Auditory Processing

Directory of Open Access Journals (Sweden)

Beate Sabisch

2013-07-01

Full Text Available Efficient auditory processing is hypothesized to support language and literacy development. However, behavioral tasks used to assess this hypothesis need to be robust to non-auditory specific individual differences. This study compared frequency discrimination abilities in a heterogeneous sample of adults using two different psychoacoustic task designs, referred to here as: 2I_6A_X and 3I_2AFC designs. The role of individual differences in nonverbal IQ (NVIQ, socioeconomic status (SES and musical experience in predicting frequency discrimination thresholds on each task were assessed using multiple regression analyses. The 2I_6A_X task was more cognitively demanding and hence more susceptible to differences specifically in SES and musical training. Performance on this task did not, however, relate to nonword repetition ability (a measure of language learning capacity. The 3I_2AFC task, by contrast, was only susceptible to musical training. Moreover, thresholds measured using it predicted some variance in nonword repetition performance. This design thus seems suitable for use in studies addressing questions regarding the role of auditory processing in supporting language and literacy development.

Repetition priming of face recognition in a serial choice reaction-time task.

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Roberts, T; Bruce, V

1989-05-01

Marshall & Walker (1987) found that pictorial stimuli yield visual priming that is disrupted by an unpredictable visual event in the response-stimulus interval. They argue that visual stimuli are represented in memory in the form of distinct visual and object codes. Bruce & Young (1986) propose similar pictorial, structural and semantic codes which mediate the recognition of faces, yet repetition priming results obtained with faces as stimuli (Bruce & Valentine, 1985), and with objects (Warren & Morton, 1982) are quite different from those of Marshall & Walker (1987), in the sense that recognition is facilitated by pictures presented 20 minutes earlier. The experiment reported here used different views of familiar and unfamiliar faces as stimuli in a serial choice reaction-time task and found that, with identical pictures, repetition priming survives and intervening item requiring a response, with both familiar and unfamiliar faces. Furthermore, with familiar faces such priming was present even when the view of the prime was different from the target. The theoretical implications of these results are discussed.

Repetition and masked form priming within and between languages using word and nonword neighbors

NARCIS (Netherlands)

Dijkstra, A.F.J.; Hilberink-Schulpen, B.J.H.; Heuven, W.J.B. van

2010-01-01

If access to the bilingual lexicon takes place in a language independent way, monolingual repetition and masked form, priming accounts should be directly applicable to bilinguals. We tested such an account (Grainger and Jacobs, 1999) and extended it to explain bilingual ejects from L2 to L1. Dutch

Role of Working Memory in Typically Developing Children's Complex Sentence Comprehension

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Montgomery, James W.; Magimairaj, Beula M.; O'Malley, Michelle H.

2008-01-01

The influence of three mechanisms of working memory (phonological short-term memory (PSTM capacity), attentional resource control/allocation, and processing speed) on children's complex (and simple) sentence comprehension was investigated. Fifty two children (6-12 years) completed a nonword repetition task (indexing PSTM), concurrent verbal…

Effects of a cognitive dual task on variability and local dynamic stability in sustained repetitive arm movements using principal component analysis: a pilot study.

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Longo, Alessia; Federolf, Peter; Haid, Thomas; Meulenbroek, Ruud

2018-06-01

In many daily jobs, repetitive arm movements are performed for extended periods of time under continuous cognitive demands. Even highly monotonous tasks exhibit an inherent motor variability and subtle fluctuations in movement stability. Variability and stability are different aspects of system dynamics, whose magnitude may be further affected by a cognitive load. Thus, the aim of the study was to explore and compare the effects of a cognitive dual task on the variability and local dynamic stability in a repetitive bimanual task. Thirteen healthy volunteers performed the repetitive motor task with and without a concurrent cognitive task of counting aloud backwards in multiples of three. Upper-body 3D kinematics were collected and postural reconfigurations-the variability related to the volunteer's postural change-were determined through a principal component analysis-based procedure. Subsequently, the most salient component was selected for the analysis of (1) cycle-to-cycle spatial and temporal variability, and (2) local dynamic stability as reflected by the largest Lyapunov exponent. Finally, end-point variability was evaluated as a control measure. The dual cognitive task proved to increase the temporal variability and reduce the local dynamic stability, marginally decrease endpoint variability, and substantially lower the incidence of postural reconfigurations. Particularly, the latter effect is considered to be relevant for the prevention of work-related musculoskeletal disorders since reduced variability in sustained repetitive tasks might increase the risk of overuse injuries.

Effects of Repetitive Transcranial Magnetic Stimulation in Performing Eye-Hand Integration Tasks: Four Preliminary Studies with Children Showing Low-Functioning Autism

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Panerai, Simonetta; Tasca, Domenica; Lanuzza, Bartolo; Trubia, Grazia; Ferri, Raffaele; Musso, Sabrina; Alagona, Giovanna; Di Guardo, Giuseppe; Barone, Concetta; Gaglione, Maria P.; Elia, Maurizio

2014-01-01

This report, based on four studies with children with low-functioning autism, aimed at evaluating the effects of repetitive transcranial magnetic stimulation delivered on the left and right premotor cortices on eye-hand integration tasks; defining the long-lasting effects of high-frequency repetitive transcranial magnetic stimulation; and…

The Relationships among Cognitive Correlates and Irregular Word, Non-Word, and Word Reading

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Abu-Hamour, Bashir; University, Mu'tah; Urso, Annmarie; Mather, Nancy

2012-01-01

This study explored four hypotheses: (a) the relationships among rapid automatized naming (RAN) and processing speed (PS) to irregular word, non-word, and word reading; (b) the predictive power of various RAN and PS measures, (c) the cognitive correlates that best predicted irregular word, non-word, and word reading, and (d) reading performance of…

Effects of modality and repetition in a continuous recognition memory task: Repetition has no effect on auditory recognition memory.

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Amir Kassim, Azlina; Rehman, Rehan; Price, Jessica M

2018-04-01

Previous research has shown that auditory recognition memory is poorer compared to visual and cross-modal (visual and auditory) recognition memory. The effect of repetition on memory has been robust in showing improved performance. It is not clear, however, how auditory recognition memory compares to visual and cross-modal recognition memory following repetition. Participants performed a recognition memory task, making old/new discriminations to new stimuli, stimuli repeated for the first time after 4-7 intervening items (R1), or repeated for the second time after 36-39 intervening items (R2). Depending on the condition, participants were either exposed to visual stimuli (2D line drawings), auditory stimuli (spoken words), or cross-modal stimuli (pairs of images and associated spoken words). Results showed that unlike participants in the visual and cross-modal conditions, participants in the auditory recognition did not show improvements in performance on R2 trials compared to R1 trials. These findings have implications for pedagogical techniques in education, as well as for interventions and exercises aimed at boosting memory performance. Copyright © 2018 Elsevier B.V. All rights reserved.

A strategy for improving worker satisfaction and job attitudes in a repetitive industrial task: application of production standards and performance feedback.

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Shikdar, Ashraf A; Das, Biman

2003-04-15

Worker satisfaction improved significantly as a consequence of the provision of the assigned and participative standards with performance feedback in a repetitive industrial production task. The maximum improvement in worker satisfaction was found for the participative standard and feedback condition. Only this condition had a significant positive effect on worker job attitudes. Monetary incentive, when provided with an assigned or participative standard with feedback, added no incremental worker satisfaction or job attitudes gain. The participative standard with feedback condition emerges as the optimum strategy for improving worker satisfaction and job attitudes in a repetitive industrial production task.

Word position and stress effects in consonant cluster perception and production.

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Cilibrasi, Luca; Stojanovik, Vesna; Riddell, Patricia

2015-02-01

The aim of the present study was to investigate whether the saliency effect for word beginnings reported in children with dyslexia (Marshall & Van der Lely, 2009) can be found also in typically developing children. Thirty-four typically developing Italian children aged 8-10 years completed two specifically designed tasks: a production task and a perception task. Both tasks used nonwords containing clusters consisting of plosive plus liquid (e.g. pl). Clusters could be either in a stressed or in an unstressed syllable and could be either in initial position (first syllable) or in medial position (second syllable). In the production task, children were asked to repeat the nonwords. In the perception task, the children were asked to discriminate between two nonwords differing in one phoneme belonging to a cluster by reporting whether two repetitions were the same or different. Results from the production task showed that children are more accurate in repeating stressed than unstressed syllables, but there was no difference with respect to position of the cluster. Results from the perception task showed that children performed more accurately when discriminating word initial contrasts than when discriminating word medial contrasts, especially if the cluster was unstressed. Implications of this finding for clinical assessments are discussed. Copyright © 2015 John Wiley & Sons, Ltd.

A diffusion decision model analysis of evidence variability in the lexical decision task.

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Tillman, Gabriel; Osth, Adam F; van Ravenzwaaij, Don; Heathcote, Andrew

2017-12-01

The lexical-decision task is among the most commonly used paradigms in psycholinguistics. In both the signal-detection theory and Diffusion Decision Model (DDM; Ratcliff, Gomez, & McKoon, Psychological Review, 111, 159-182, 2004) frameworks, lexical-decisions are based on a continuous source of word-likeness evidence for both words and non-words. The Retrieving Effectively from Memory model of Lexical-Decision (REM-LD; Wagenmakers et al., Cognitive Psychology, 48(3), 332-367, 2004) provides a comprehensive explanation of lexical-decision data and makes the prediction that word-likeness evidence is more variable for words than non-words and that higher frequency words are more variable than lower frequency words. To test these predictions, we analyzed five lexical-decision data sets with the DDM. For all data sets, drift-rate variability changed across word frequency and non-word conditions. For the most part, REM-LD's predictions about the ordering of evidence variability across stimuli in the lexical-decision task were confirmed.

Working memory and sentence comprehension of Hong Kong Chinese children with specific language impairment.

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Siu, Elaine; Man, David W K

2006-09-01

Children with Specific Language Impairment present with delayed language development, but do not have a history of hearing impairment, mental deficiency, or associated social or behavioral problems. Non-word repetition was suggested as an index to reflect the capacity of phonological working memory. There is a paucity of such studies among Hong Kong Chinese children. This preliminary study aimed to examine the relationship between phonological working memory and Specific Language Impairment, through the processes of non-word repetition and sentence comprehension, of children with Specific Language Impairment and pre-school children with normal language development. Both groups of children were screened by a standardized language test. A list of Cantonese (the commonest dialect used in Hong Kong) multisyllabic nonsense utterances and a set of 18 sentences were developed for this study. t-tests and Pearson correlation were used to study the relationship between non-word repetition, working memory and specific language impairment. Twenty-three pre-school children with Specific Language Impairment (mean age = 68.30 months; SD = 6.90) and another 23 pre-school children (mean age = 67.30 months; SD = 6.16) participated in the study. Significant difference performance was found between the Specific Language Impairment group and normal language group in the multisyllabic nonsense utterances repetition task and the sentence comprehension task. Length effect was noted in Specific Language Impairment group children, which is consistent with the findings of other literature. In addition, correlations were also observed between the number of nonsense utterances repeated and the number of elements comprehended. Cantonese multisyllabic nonsense utterances might be worth further developing as a screening tool for the early detection of children with Specific Language Impairment.

Speech Motor Sequence Learning: Acquisition and Retention in Parkinson Disease and Normal Aging

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Whitfield, Jason A.; Goberman, Alexander M.

2017-01-01

Purpose: The aim of the current investigation was to examine speech motor sequence learning in neurologically healthy younger adults, neurologically healthy older adults, and individuals with Parkinson disease (PD) over a 2-day period. Method: A sequential nonword repetition task was used to examine learning over 2 days. Participants practiced a…

Reevaluating split-fovea processing in word recognition: hemispheric dominance, retinal location, and the word-nonword effect.

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Jordan, Timothy R; Paterson, Kevin B; Kurtev, Stoyan

2009-03-01

Many studies have claimed that hemispheric projections are split precisely at the foveal midline and so hemispheric asymmetry affects word recognition right up to the point of fixation. To investigate this claim, four-letter words and nonwords were presented to the left or right of fixation, either close to fixation in foveal vision or farther from fixation in extrafoveal vision. Presentation accuracy was controlled using an eyetracker linked to a fixation-contingent display. Words presented foveally produced identical performance on each side of fixation, but words presented extrafoveally showed a clear left-hemisphere (LH) advantage. Nonwords produced no evidence of hemispheric asymmetry in any location. Foveal stimuli also produced an identical word-nonword effect on each side of fixation, whereas extrafoveal stimuli produced a word-nonword effect only for LH (not right-hemisphere) displays. These findings indicate that functional unilateral projections to contralateral hemispheres exist in extrafoveal locations but provide no evidence of a functional division in hemispheric processing at fixation.

The Role of Phonological Working Memory and Environmental Factors in Lexical Development in Italian-Speaking Late Talkers: A One-Year Follow-Up Study

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Marini, Andrea; Ruffino, Milena; Sali, Maria Enrica; Molteni, Massimo

2017-01-01

Purpose: This follow-up study assessed (a) the influence of phonological working memory (pWM), home literacy environment, and a family history of linguistic impairments in late talkers (LTs); (b) the diagnostic accuracy of a task of nonword repetition (NWR) in identifying LTs; and (c) the persistence of lexical weaknesses after 10 months. Method:…

Why chunking should be considered as an explanation for developmental change before short-term memory capacity and processing speed

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Gary eJones

2012-06-01

Full Text Available The chunking hypothesis suggests that during the repeated exposure of stimulus material, information is organized into increasingly larger chunks. Many researchers have not considered the full power of the chunking hypothesis as both a learning mechanism and as an explanation of human behavior. Indeed, in developmental psychology there is relatively little mention of chunking and yet it can be the underlying cause of some of the mechanisms of development that have been proposed. This paper illustrates the chunking hypothesis in the domain of nonword repetition, a task that is a strong predictor of a child’s language learning. A computer simulation of nonword repetition that instantiates the chunking mechanism shows that: (1 chunking causes task behavior to improve over time, consistent with children’s performance; and (2 chunking causes perceived changes in areas such as short-term memory capacity and processing speed that are often cited as mechanisms of child development. Researchers should be cautious when considering explanations of developmental data, since chunking may be able to explain differences in performance without the need for additional mechanisms of development.

Gender differences in workers with identical repetitive industrial tasks: exposure and musculoskeletal disorders.

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Nordander, Catarina; Ohlsson, Kerstina; Balogh, Istvan; Hansson, Gert-Ake; Axmon, Anna; Persson, Roger; Skerfving, Staffan

2008-08-01

For unknown reasons, females run a higher risk than males of work-related musculoskeletal disorders. The aim of this study was to evaluate whether male and female workers, with identical repetitive work tasks, differ concerning risk of disorders, physical or psychosocial exposures. Employees in two industries were studied; one rubber manufacturing and one mechanical assembly plant. These industries were selected since in both, large groups of males and females worked side by side performing identical repetitive work tasks. Physical exposure was measured by technical equipment. Postures and movements were registered by inclinometry for the head and upper arms, and by electrogoniometry for the wrists. Muscular activity (muscular rest and %max) was registered by surface electromyography for m. trapezius and the forearm extensors (18 males and 19 females). Psychosocial work environment was evaluated by the demand-control-support model (85 males and 138 females). Musculoskeletal disorders were assessed (105 males and 172 females), by interview (last 7-days complaints), and by physical examination (diagnoses). Concerning physical exposure, females showed higher muscular activity related to maximal voluntary contractions [(%MVE); m. trapezius: females 18 (SD 9.2), males 12 (SD 4.3); forearm extensors: females 39 (SD 11), males 27 (SD 10), right side, 90th percentile]. Working postures and movements were similar between genders. Also, concerning psychosocial work environment, no significant gender differences were found. Females had higher prevalences of disorders [complaints: age-adjusted prevalence odds ratio (POR) 2.3 (95% CI 1.3-3.8) for neck/shoulders, 2.4 (1.4-4.0) for elbows/hands; diagnoses: neck/shoulder 1.9 (1.1-3.6), elbows/hands 4.1 (1.2-9.3)]. In 225 workers, PORs were adjusted for household work, personal recovery and exercise, which only slightly affected the risk estimates. In identical work tasks, females showed substantially higher muscular activity in

The roles of stimulus repetition and hemispheric activation in visual half-field asymmetries.

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Sullivan, K F; McKeever, W F

1985-10-01

Hardyck, Tzeng, and Wang (1978, Brain and Language, 5, 56-71) hypothesized that ample repetition of a small number of stimuli is required in order to obtain VHF differences in tachistoscopic tasks. Four experiments, with varied levels of repetition, were conducted to test this hypothesis. Three experiments utilized the general task of object-picture naming and one utilized a word-naming task. Naming latencies constituted the dependent measure. The results demonstrate that for the object-naming paradigm repetition is required for RVF superiority to emerge. Repetition was found to be unnecessary for RVF superiority in the word-naming paradigm, with repetition actually reducing RVF superiority. Experiment I suggested the possibility that RVF superiority developed for the second half of the trials as a function of practice or hemispheric activation, regardless of repetition level. Subsequent experiments, better designed to assess this possibility, clearly refuted it. It was concluded that the effect of repetition depends on the processing requirements of the task. We propose that, for tasks which can be processed efficiently by one hemisphere, the effect of repetition will be to reduce VHF asymmetries; but tasks requiring substantial processing by both hemispheres will show shifts to RVF superiority as a function of repetition.

Cognitive Impairments and Depressive Symptoms Did Not Impede Upper Extremity Recovery in a Clinical Repetitive Task Practice Program after Stroke

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Skidmore, Elizabeth R.; Becker, James T.; Whyte, Ellen M.; Huber, Lynne M.; Waterstram, Laura F.; Ward, Amalie Andrew; Grattan, Emily S.; Holm, Margo B.

2012-01-01

Objective We examined whether cognitive impairments or depressive symptoms impeded improvement in upper extremity function in a clinical repetitive task practice program. Design Participants had mild to moderate upper extremity impairment after stroke (n=20). We characterized baseline cognitive function and depressive symptoms with the Repeatable Battery of Neuropsychological Status and the Hamilton Rating Scale for Depression. We measured upper extremity function at baseline, week 4 and week 24 with the Action Research Arm Test. Results Participants with and without cognitive impairments improved significantly over time (F1,17=84.48, pstroke (t17=.07, p=.95). Participants with and without depressive symptoms improved significantly over time (F1,18=86.29, pstroke (t17=.06, p=.95). Conclusions Preliminary findings suggest that cognitive impairments and depressive symptoms may not impede benefit from repetitive task practice after stroke. PMID:22311057

The influences of task repetition, napping, time of day, and instruction on the Sustained Attention to Response Task.

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van Schie, Mojca K M; Alblas, Eva E; Thijs, Roland D; Fronczek, Rolf; Lammers, Gert Jan; van Dijk, J Gert

2014-01-01

The Sustained Attention to Response Task (SART) helps to quantify vigilance impairments.Previous studies, in which five SART sessions on one day were administered, demonstrated worse performance during the first session than during the others. The present study comprises two experiments to identify a cause of this phenomenon. Experiment 1, counting eighty healthy participants, assessed effects of repetition,napping, and time of day on SART performance through a between-groups design. The SART was performed twice in the morning or twice in the afternoon; half of the participants took a 20-minute nap before the second SART. A strong correlation between error count and reaction time (RT) suggested effects of test instruction. Participants gave equal weight to speed and accuracy in Experiment 1; therefore, results of 20 participants were compared to those of 20 additional participants who were told to prefer accuracy (Experiment 2). The average SART error count in Experiment 1 was 10.1; the median RT was 280 ms. Neither repetition nor napping influenced error count or RT. Time of day did not influence error count, but RT was significantly longer for morning than for afternoon SARTs. The additional participants in Experiment 2 had a 49% lower error count and a 14% higher RT than the participants in Experiment 1. Error counts reduced by 50% from the first to the second session of Experiment 2, irrespective of napping or time of day. Preferring accuracy over speed was associated with a significantly lower error count. The data suggest that a worse performance in the first SART session only occurs when instructing participants to prefer accuracy, which is caused by repetition, not by napping or time of day. We advise that participants are instructed to prefer accuracy over speed when performing the SART and that a full practice session is included.

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.

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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.

Does Phonological Short-Term Memory Causally Determine Vocabulary Learning? Toward a Computational Resolution of the Debate

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Gupta, Prahlad; Tisdale, Jamie

2009-01-01

The relationship between nonword repetition ability and vocabulary size and vocabulary learning has been a topic of intense research interest and investigation over the last two decades, following the demonstration that nonword repetition accuracy is predictive of vocabulary size (Gathercole & Baddeley, 1989). However, the nature of this…

Learning better by repetition or variation? Is transfer at odds with task specific training?

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Emmanuel Bonney

Full Text Available Transfer of motor skills is the ultimate goal of motor training in rehabilitation practice. In children with Developmental Coordination Disorder (DCD, very little is known about how skills are transferred from training situations to real life contexts. In this study we examined the influence of two types of practice on transfer of motor skills acquired in a virtual reality (VR environment.One hundred and eleven children with DCD and their typically developing (TD peers, aged 6-10 years (M = 8.0 SD = 1.0 were randomly assigned to either variable (n = 56 or repetitive practice (n = 55. Participants in the repetitive practice played the same exergame (ski slalom twice weekly for 20 minutes, over a period of 5 weeks, while those in the variable group played 10 different games. Motor skills such as balance tasks (hopping, running and agility tasks, ball skills and functional activities were evaluated before and after 5 weeks of training.ANOVA repeated measures indicated that both DCD and TD children demonstrated transfer effects to real life skills with identical and non-identical elements at exactly the same rate, irrespective of the type of practice they were assigned to.Based on these findings, we conclude that motor skills acquired in the VR environment, transfers to real world contexts in similar proportions for both TD and DCD children. The type of practice adopted does not seem to influence children's ability to transfer skills acquired in an exergame to life situations but the number of identical elements does.

Beyond Words: Phonological Short-Term Memory and Syntactic Impairment in Specific Language Impairment

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Bishop, Dorothy V. M.

2006-01-01

The assessment of nonword repetition in children goes back at least to 1974, when the Goldman-Fristoe-Woodcock Auditory Skills Battery was published, including a subtest (Sound Mimicry) assessing nonword repetition (Goldman, Fristoe, & Woodcock, 1974). Nevertheless, it was not until 20 years later, when Gathercole and Baddeley (1990) reported a…

Commentary on Keynote

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Gray, Shelley

2006-01-01

Our understanding the relationship between verbal short-term memory as indexed by nonword repetition and word learning must now incorporate myriad factors that were not as apparent 17 years ago when Gathercole and Baddeley (1989) proposed that "the phonological memory skills tapped by nonword repetition play a causal role in vocabulary…

Functional dissociations in top-down control dependent neural repetition priming.

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Klaver, P.; Schnaidt, M.; Fell, J.; Ruhlmann, J.; Elger, C.E.; Fernandez, G.S.E.

2007-01-01

Little is known about the neural mechanisms underlying top-down control of repetition priming. Here, we use functional brain imaging to investigate these mechanisms. Study and repetition tasks used a natural/man-made forced choice task. In the study phase subjects were required to respond to either

Electrophysiological Repetition Effects in Persons with Mild Cognitive Impairment depend upon Working Memory Demand.

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Broster, Lucas S; Jenkins, Shonna L; Holmes, Sarah D; Edwards, Matthew G; Jicha, Gregory A; Jiang, Yang

2018-05-07

Forms of implicit memory, including repetition effects, are preserved relative to explicit memory in clinical Alzheimer's disease. Consequently, cognitive interventions for persons with Alzheimer's disease have been developed that leverage this fact. However, despite the clinical robustness of behavioral repetition effects, altered neural mechanisms of repetition effects are studied as biomarkers of both clinical Alzheimer's disease and pre-morbid Alzheimer's changes in the brain. We hypothesized that the clinical preservation of behavioral repetition effects results in part from concurrent operation of discrete memory systems. We developed two experiments that included probes of emotional repetition effects differing in that one included an embedded working memory task. We found that neural repetition effects manifested in patients with amnestic mild cognitive impairment, the earliest form of clinical Alzheimer's disease, during emotional working memory tasks, but they did not manifest during the task that lacked the embedded working memory manipulation. Specifically, the working memory task evoked neural repetition effects in the P600 time-window, but the same neural mechanism was only minimally implicated in the task without a working memory component. We also found that group differences in behavioral repetition effects were smaller in the experiment with a working memory task. We suggest that cross-domain cognitive challenge can expose "defunct" neural capabilities of individuals with amnestic mild cognitive impairment. Copyright © 2018. Published by Elsevier Ltd.

Lingual Kinematics during Rapid Syllable Repetition in Parkinson's Disease

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Wong, Min Ney; Murdoch, Bruce E.; Whelan, Brooke-Mai

2012-01-01

Background: Rapid syllable repetition tasks are commonly used in the assessment of motor speech disorders. However, little is known about the articulatory kinematics during rapid syllable repetition in individuals with Parkinson's disease (PD). Aims: To investigate and compare lingual kinematics during rapid syllable repetition in dysarthric…

Articulation of Phonologically Similar Items Disrupts Free Recall of Nonwords

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Nishiyama, Ryoji; Ukita, Jun

2013-01-01

The present study sought to clarify whether phonological similarity of encoded information impairs free recall performance (the phonological similarity effect: PSE) for nonwords. Five experiments examined the influence of the encoding process on the PSE in a step-by-step fashion, by using lists that consisted of phonologically similar (decoy)…

When predictions take control: The effect of task predictions on task switching performance

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Wout eDuthoo

2012-08-01

Full Text Available In this paper, we aimed to investigate the role of self-generated predictions in the flexible control of behaviour. Therefore, we ran a task switching experiment in which participants were asked to try to predict the upcoming task in three conditions varying in switch rate (30%, 50% and 70%. Irrespective of their predictions, the colour of the target indicated which task participants had to perform. In line with previous studies (Mayr, 2006; Monsell & Mizon, 2006, the switch cost was attenuated as the switch rate increased. Importantly, a clear task repetition bias was found in all conditions, yet the task repetition prediction rate dropped from 78% over 66% to 49% with increasing switch probability in the three conditions. Irrespective of condition, the switch cost was strongly reduced in expectation of a task alternation compared to the cost of an unexpected task alternation following repetition predictions. Hence, our data suggest that the reduction in the switch cost with increasing switch probability is caused by a diminished expectancy for the task to repeat. Taken together, this paper highlights the importance of predictions in the flexible control of behaviour, and suggests a crucial role for task repetition expectancy in the context-sensitive adjusting of task switching performance.

Long-term associative learning predicts verbal short-term memory performance.

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Jones, Gary; Macken, Bill

2018-02-01

Studies using tests such as digit span and nonword repetition have implicated short-term memory across a range of developmental domains. Such tests ostensibly assess specialized processes for the short-term manipulation and maintenance of information that are often argued to enable long-term learning. However, there is considerable evidence for an influence of long-term linguistic learning on performance in short-term memory tasks that brings into question the role of a specialized short-term memory system separate from long-term knowledge. Using natural language corpora, we show experimentally and computationally that performance on three widely used measures of short-term memory (digit span, nonword repetition, and sentence recall) can be predicted from simple associative learning operating on the linguistic environment to which a typical child may have been exposed. The findings support the broad view that short-term verbal memory performance reflects the application of long-term language knowledge to the experimental setting.

Modulation of Brain Activity during Phonological Familiarization

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Majerus, S.; Van der Linden, M.; Collette, F.; Laureys, S.; Poncelet, M.; Degueldre, C.; Delfiore, G.; Luxen, A.; Salmon, E.

2005-01-01

We measured brain activity in 12 adults for the repetition of auditorily presented words and nonwords, before and after repeated exposure to their phonological form. The nonword phoneme combinations were either of high (HF) or low (LF) phonotactic frequency. After familiarization, we observed, for both word and nonword conditions, decreased…

Sound segregation via embedded repetition is robust to inattention.

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Masutomi, Keiko; Barascud, Nicolas; Kashino, Makio; McDermott, Josh H; Chait, Maria

2016-03-01

The segregation of sound sources from the mixture of sounds that enters the ear is a core capacity of human hearing, but the extent to which this process is dependent on attention remains unclear. This study investigated the effect of attention on the ability to segregate sounds via repetition. We utilized a dual task design in which stimuli to be segregated were presented along with stimuli for a "decoy" task that required continuous monitoring. The task to assess segregation presented a target sound 10 times in a row, each time concurrent with a different distractor sound. McDermott, Wrobleski, and Oxenham (2011) demonstrated that repetition causes the target sound to be segregated from the distractors. Segregation was queried by asking listeners whether a subsequent probe sound was identical to the target. A control task presented similar stimuli but probed discrimination without engaging segregation processes. We present results from 3 different decoy tasks: a visual multiple object tracking task, a rapid serial visual presentation (RSVP) digit encoding task, and a demanding auditory monitoring task. Load was manipulated by using high- and low-demand versions of each decoy task. The data provide converging evidence of a small effect of attention that is nonspecific, in that it affected the segregation and control tasks to a similar extent. In all cases, segregation performance remained high despite the presence of a concurrent, objectively demanding decoy task. The results suggest that repetition-based segregation is robust to inattention. (c) 2016 APA, all rights reserved).

Postural reconfiguration and cycle-to-cycle variability in patients with work-related musculoskeletal disorders compared to healthy controls and in relation to pain emerging during a repetitive movement task

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Longo, A.; Meulenbroek, R.G.J.; Haid, T.; Federolf, P.A.

2018-01-01

Background: Movement variability in sustained repetitive tasks is an important factor in the context of work-related musculoskeletal disorders. While a popular hypothesis suggests that movement variability can prevent overuse injuries, pain evolving during task execution may also cause variability.

Effects of task structure on category priming in patients with Parkinson's disease and in healthy individuals.

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Brown, Gregory G; Brown, Sandra J; Christenson, Gina; Williams, Rebecca E; Kindermann, Sandra S; Loftis, Christopher; Olsen, Ryan; Siple, Patricia; Shults, Clifford; Gorell, Jay M

2002-05-01

Lexical decision tasks have been used to study both shifts of attention and semantic processing in Parkinson's Disease (PD). Whereas other laboratories have reported normal levels of semantic priming among PD patients, our laboratory has reported abnormally large levels. In this study, two experiments were performed to determine the influence of task structure on the extent of semantic priming during lexical decision-making and pronunciation tasks among PD patients and neurologically healthy controls. In Experiment 1, the effect of Prime Dominance (the ratio of category to neutral trials) on lexical decision-making was studied. Although equal numbers of word and nonword trials were presented, half of the PD patients and controls were studied under Category Prime Dominance (category : neutral prime ratio of 2:1) and half were studied under Neutral Prime Dominance (category : neutral prime ratio of 1:2). In Experiment 2, PD and control participants were studied on lexical decision-making and pronunciation tasks where twice as many words as nonword trials were presented, consistent with other studies from our laboratory. In Experiment 1, we found no group differences in the magnitude of priming and no effect of Prime Dominance. Moreover, the findings were similar in pattern and magnitude to results published by Neely (1977). In Experiment 2, we observed larger priming effects among PD patients than among controls, but only on the lexical decision (LD) task. These results support the hypothesis that abnormally large category-priming effects appear in LD studies of PD patients when the number of word trials exceeds the number of nonword trials. Furthermore, increased lexical priming in PD appears to be due to processes operating during the decision-making period that follows presentation of the lexical target.

Preposition accuracy on a sentence repetition task in school age Spanish–English bilinguals*

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TALIANCICH-KLINGER, CASEY L.; BEDORE, LISA M.; PEÑA, ELIZABETH D.

2018-01-01

Preposition knowledge is important for academic success. The goal of this project was to examine how different variables such as English input and output, Spanish preposition score, mother education level, and age of English exposure (AoEE) may have played a role in children’s preposition knowledge in English. 148 Spanish–English children between 7;0 and 9;11 produced prepositions in English and Spanish on a sentence repetition task from an experimental version of the Bilingual English Spanish Assessment Middle Extension (Peña, Bedore, Gutierrez-Clellen, Iglesias & Goldstein, in development). English input and output accounted for most of the variance in English preposition score. The importance of language-specific experiences in the development of prepositions is discussed. Competition for selection of appropriate prepositions in English and Spanish is discussed as potentially influencing low overall preposition scores in English and Spanish. PMID:28506324

Motor adaptation capacity as a function of age in carrying out a repetitive assembly task at imposed work paces.

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Gilles, Martine Annie; Guélin, Jean-Charles; Desbrosses, Kévin; Wild, Pascal

2017-10-01

The working population is getting older. Workers must adapt to changing conditions to respond to the efforts required by the tasks they have to perform. In this laboratory-based study, we investigated the capacities of motor adaptation as a function of age and work pace. Two phases were identified in the task performed: a collection phase, involving dominant use of the lower limbs; and an assembly phase, involving bi-manual motor skills. Results showed that senior workers were mainly limited during the collection phase, whereas they had less difficulty completing the assembly phase. However, senior workers did increase the vertical force applied while assembling parts, whatever the work pace. In younger and middle-aged subjects, vertical force was increased only for the faster pace. Older workers could adapt to perform repetitive tasks under different time constraints, but adaptation required greater effort than for younger workers. These results point towards a higher risk of developing musculoskeletal disorders among seniors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Corticospinal excitability during the processing of handwritten and typed words and non-words.

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Gordon, Chelsea L; Spivey, Michael J; Balasubramaniam, Ramesh

2017-06-09

A number of studies have suggested that perception of actions is accompanied by motor simulation of those actions. To further explore this proposal, we applied Transcranial magnetic stimulation (TMS) to the left primary motor cortex during the observation of handwritten and typed language stimuli, including words and non-word consonant clusters. We recorded motor-evoked potentials (MEPs) from the right first dorsal interosseous (FDI) muscle to measure cortico-spinal excitability during written text perception. We observed a facilitation in MEPs for handwritten stimuli, regardless of whether the stimuli were words or non-words, suggesting potential motor simulation during observation. We did not observe a similar facilitation for the typed stimuli, suggesting that motor simulation was not occurring during observation of typed text. By demonstrating potential simulation of written language text during observation, these findings add to a growing literature suggesting that the motor system plays a strong role in the perception of written language. Copyright © 2017 Elsevier B.V. All rights reserved.

Long-term associative learning predicts verbal short-term memory performance

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Jones, Gary; Macken, Bill

2017-01-01

Studies using tests such as digit span and nonword repetition have implicated short-term memory across a range of developmental domains. Such tests ostensibly assess specialized processes for the short-term manipulation and maintenance of information that are often argued to enable long-term learning. However, there is considerable evidence for an influence of long-term linguistic learning on performance in short-term memory tasks that brings into question the role of a specialized short-term...

Repetition Blindness: Out of Sight or Out of Mind?

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Morris, Alison L.; Harris, Catherine L.

2004-01-01

Does repetition blindness represent a failure of perception or of memory? In Experiment 1, participants viewed rapid serial visual presentation (RSVP) sentences. When critical words (C1 and C2) were orthographically similar, C2 was frequently omitted from serial report; however, repetition priming for C2 on a postsentence lexical decision task was…

Matching is not naming: a direct comparison of lexical manipulations in explicit and implicit reading tasks.

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Vogel, Alecia C; Petersen, Steven E; Schlaggar, Bradley L

2013-10-01

The neurobiological basis of reading is of considerable interest, yet analyzing data from subjects reading words aloud during functional MRI data collection can be difficult. Therefore, many investigators use surrogate tasks such as visual matching or rhyme matching to eliminate the need for spoken output. Use of these tasks has been justified by the presumption of "automatic activation" of reading-related neural processing when a word is viewed. We have tested the efficacy of using a nonreading task for studying "reading effects" by directly comparing blood oxygen level dependent (BOLD) activity in subjects performing a visual matching task and an item naming task on words, pseudowords (meaningless but legal letter combinations), and nonwords (meaningless and illegal letter combinations). When compared directly, there is significantly more activity during the naming task in "reading-related" regions such as the inferior frontal gyrus (IFG) and supramarginal gyrus. More importantly, there are differing effects of lexicality in the tasks. A whole-brain task (matching vs. naming) by string type (word vs. pseudoword vs. nonword) by BOLD timecourse analysis identifies regions showing this three-way interaction, including the left IFG and left angular gyrus (AG). In the majority of the identified regions (including the left IFG and left AG), there is a string type × timecourse interaction in the naming but not the matching task. These results argue that the processing performed in specific regions is contingent on task, even in reading-related regions and is thus nonautomatic. Such differences should be taken into consideration when designing studies intended to investigate reading. Copyright © 2012 Wiley Periodicals, Inc.

Independent and additive repetition priming of motion direction and color in visual search.

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Kristjánsson, Arni

2009-03-01

Priming of visual search for Gabor patch stimuli, varying in color and local drift direction, was investigated. The task relevance of each feature varied between the different experimental conditions compared. When the target defining dimension was color, a large effect of color repetition was seen as well as a smaller effect of the repetition of motion direction. The opposite priming pattern was seen when motion direction defined the target--the effect of motion direction repetition was this time larger than for color repetition. Finally, when neither was task relevant, and the target defining dimension was the spatial frequency of the Gabor patch, priming was seen for repetition of both color and motion direction, but the effects were smaller than in the previous two conditions. These results show that features do not necessarily have to be task relevant for priming to occur. There is little interaction between priming following repetition of color and motion, these two features show independent and additive priming effects, most likely reflecting that the two features are processed at separate processing sites in the nervous system, consistent with previous findings from neuropsychology & neurophysiology. The implications of the findings for theoretical accounts of priming in visual search are discussed.

Working memory load affects repetitive behaviour but not cognitive flexibility in adolescent autism spectrum disorder.

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Wolff, Nicole; Chmielewski, Witold X; Beste, Christian; Roessner, Veit

2017-03-16

Autism spectrum disorder (ASD) is associated with repetitive and stereotyped behaviour, suggesting that cognitive flexibility may be deficient in ASD. A central, yet not examined aspect to understand possible deficits in flexible behaviour in ASD relates (i) to the role of working memory and (ii) to neurophysiological mechanisms underlying behavioural modulations. We analysed behavioural and neurophysiological (EEG) correlates of cognitive flexibility using a task-switching paradigm with and without working memory load in adolescents with ASD and typically developing controls (TD). Adolescents with ASD versus TD show similar performance in task switching with no memory load, indicating that 'pure' cognitive flexibility is not in deficit in adolescent ASD. However performance during task repetition decreases with increasing memory load. Neurophysiological data reflect the pattern of behavioural effects, showing modulations in P2 and P3 event-related potentials. Working memory demands affect repetitive behaviour while processes of cognitive flexibility are unaffected. Effects emerge due to deficits in preparatory attentional processes and deficits in task rule activation, organisation and implementation of task sets when repetitive behaviour is concerned. It may be speculated that the habitual response mode in ASD (i.e. repetitive behaviour) is particularly vulnerable to additional demands on executive control processes.

Task Switching in a Hierarchical Task Structure: Evidence for the Fragility of the Task Repetition Benefit

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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.…

An effective repetitive training schedule to achieve skill proficiency using a novel robotic virtual reality simulator.

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Kang, Sung Gu; Ryu, Byung Ju; Yang, Kyung Sook; Ko, Young Hwii; Cho, Seok; Kang, Seok Ho; Patel, Vipul R; Cheon, Jun

2015-01-01

A robotic virtual reality simulator (Mimic dV-Trainer) can be a useful training method for the da Vinci surgical system. Herein, we investigate several repetitive training schedules and determine which is the most effective. A total of 30 medical students were enrolled and were divided into 3 groups according to the training schedule. Group 1 performed the task 1 hour daily for 4 consecutive days, group II performed the task on once per week for 1 hour for 4 consecutive weeks, and group III performed the task for 4 consecutive hours in 1 day. The effects of training were investigated by analyzing the number of repetitions and the time required to complete the "Tube 2" simulation task when the learning curve plateau was reached. The point at which participants reached a stable score was evaluated using the cumulative sum control graph. The average time to complete the task at the learning curve plateau was 150.3 seconds in group I, 171.9 seconds in group II, and 188.5 seconds in group III. The number of task repetitions required to reach the learning curve plateau was 45 repetitions in group I, 36 repetitions in group II, and 39 repetitions in group III. Therefore, there was continuous improvement in the time required to perform the task after 40 repetitions in group I only. There was a significant correlation between improvement in each trial interval and attempt, and the correlation coefficient (0.924) in group I was higher than that in group II (0.899) and group III (0.838). Daily 1-hour practice sessions performed for 4 consecutive days resulted in the best final score, continuous score improvement, and effective training while minimizing fatigue. This repetition schedule can be used for effectively training novices in future. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Practice Makes Perfect: Correlations Between Prior Experience in High-level Athletics and Robotic Surgical Performance Do Not Persist After Task Repetition.

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Shee, Kevin; Ghali, Fady M; Hyams, Elias S

Robotic surgical skill development is central to training in urology as well as in other surgical disciplines. Here, we describe a pilot study assessing the relationships between robotic surgery simulator performance and 3 categories of activities, namely, videogames, musical instruments, and athletics. A questionnaire was administered to preclinical medical students for general demographic information and prior experiences in surgery, videogames, musical instruments, and athletics. For follow-up performance studies, we used the Matchboard Level 1 and 2 modules on the da Vinci Skills Simulator, and recorded overall score, time to complete, economy of motion, workspace range, instrument collisions, instruments out of view, and drops. Task 1 was run once, whereas task 2 was run 3 times. All performance studies on the da Vinci Surgical Skills Simulator took place in the Simulation Center at Dartmouth-Hitchcock Medical Center. All participants were medical students at the Geisel School of Medicine. After excluding students with prior hands-on experience in surgery, a total of 30 students completed the study. We found a significant correlation between athletic skill level and performance for both task 1 (p = 0.0002) and task 2 (p = 0.0009). No significant correlations were found for videogame or musical instrument skill level. Students with experience in certain athletics (e.g., volleyball, tennis, and baseball) tended to perform better than students with experience in other athletics (e.g., track and field). For task 2, which was run 3 times, this association did not persist after the third repetition due to significant improvements in students with low-level athletic skill (levels 0-2). Our study suggests that prior experience in high-level athletics, but not videogames or musical instruments, significantly influences surgical proficiency in robot-naive students. Furthermore, our study suggests that practice through task repetition can overcome initial differences

Transcutaneous Auricular Vagus Nerve Stimulation with Concurrent Upper Limb Repetitive Task Practice for Poststroke Motor Recovery: A Pilot Study.

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Redgrave, Jessica N; Moore, Lucy; Oyekunle, Tosin; Ebrahim, Maryam; Falidas, Konstantinos; Snowdon, Nicola; Ali, Ali; Majid, Arshad

2018-03-23

Invasive vagus nerve stimulation (VNS) has the potential to enhance the effects of physiotherapy for upper limb motor recovery after stroke. Noninvasive, transcutaneous auricular branch VNS (taVNS) may have similar benefits, but this has not been evaluated in stroke recovery. We sought to determine the feasibility of taVNS delivered alongside upper limb repetitive task-specific practice after stroke and its effects on a range of outcome measures evaluating limb function. Thirteen participants at more than 3 months postischemic stroke with residual upper limb dysfunction were recruited from the community of Sheffield, United Kingdom (October-December 2016). Participants underwent 18 × 1-hour sessions over 6 weeks in which they made 30-50 repetitions of 8-10 arm movements concurrently with taVNS (NEMOS; Cerbomed, Erlangen, Germany, 25 Hz, .1-millisecond pulse width) at maximum tolerated intensity (mA). An electrocardiogram and rehabilitation outcome scores were obtained at each visit. Qualitative interviews determined the acceptability of taVNS to participants. Median time after stroke was 1.16 years, and baseline median/interquartile range upper limb Fugl-Meyer (UFM) score was 63 (54.5-99.5). Participants attended 92% of the planned treatment sessions. Three participants reported side effects, mainly fatigue, but all performed mean of more than 300 arm repetitions per session with no serious adverse events. There was a significant change in the UFM score with a mean increase per participant of 17.1 points (standard deviation 7.8). taVNS is feasible and well-tolerated alongside upper limb repetitive movements in poststroke rehabilitation. The motor improvements observed justify a phase 2 trial in patients with residual arm weakness. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Repetition and the Concept of Repetition

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Arne Grøn

2013-11-01

Full Text Available This paper offers a description of the meaning of the category of repetition. Firstly, it is pointed out that Constantin uses repetition as a concept that means the creation of epochs; the passing from Greece to Modernity is accomplished distinguishing between recollection, a concept that looks back to the past, and repetition, a concept that looks forward to future. Secondly, it is showed that the category of repetition, as a religious category, relates with what Climacus calls “ethic despair” and with what Vigilius calls “second ethics”; it is through repetition that it can be understood that sin finds its place in ethics and these shows the tension between it and dogmatics. And thirdly, it is showed that the descovery of the new category of repetition is a rediscovery of what Kierkegaard calls category of spirit; repetition has for its object the individuality, and coming to be oneself is what Kierkegaard undertands as liberty. At the end of the paper it is questioned if the category of repetition is inconsistent with the book Repetition.

A common neural substrate for language production and verbal working memory.

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Acheson, Daniel J; Hamidi, Massihullah; Binder, Jeffrey R; Postle, Bradley R

2011-06-01

Verbal working memory (VWM), the ability to maintain and manipulate representations of speech sounds over short periods, is held by some influential models to be independent from the systems responsible for language production and comprehension [e.g., Baddeley, A. D. Working memory, thought, and action. New York, NY: Oxford University Press, 2007]. We explore the alternative hypothesis that maintenance in VWM is subserved by temporary activation of the language production system [Acheson, D. J., & MacDonald, M. C. Verbal working memory and language production: Common approaches to the serial ordering of verbal information. Psychological Bulletin, 135, 50-68, 2009b]. Specifically, we hypothesized that for stimuli lacking a semantic representation (e.g., nonwords such as mun), maintenance in VWM can be achieved by cycling information back and forth between the stages of phonological encoding and articulatory planning. First, fMRI was used to identify regions associated with two different stages of language production planning: the posterior superior temporal gyrus (pSTG) for phonological encoding (critical for VWM of nonwords) and the middle temporal gyrus (MTG) for lexical-semantic retrieval (not critical for VWM of nonwords). Next, in the same subjects, these regions were targeted with repetitive transcranial magnetic stimulation (rTMS) during language production and VWM task performance. Results showed that rTMS to the pSTG, but not the MTG, increased error rates on paced reading (a language production task) and on delayed serial recall of nonwords (a test of VWM). Performance on a lexical-semantic retrieval task (picture naming), in contrast, was significantly sensitive to rTMS of the MTG. Because rTMS was guided by language production-related activity, these results provide the first causal evidence that maintenance in VWM directly depends on the long-term representations and processes used in speech production.

Understanding work related musculoskeletal pain: does repetitive work cause stress symptoms?

DEFF Research Database (Denmark)

Bonde, J. P.; Mikkelsen, S.; Andersen, JH

2005-01-01

for development of regional pain in repetitive work, stress symptoms would likely be on the causal path. AIMS: To examine whether objective measures of repetitive monotonous work are related to occurrence and development of stress symptoms. METHODS: In 1994-95, 2033 unskilled workers with continuous repetitive...... Profile Inventory. RESULTS: Repetitive work, task cycle time, and quantified measures of repetitive upper extremity movements including force requirements were not related to occurrence of stress symptoms at baseline or development of stress symptoms during three years of follow up. CONCLUSIONS......: The findings do not indicate that repetitive work is associated with stress symptoms, but small effects cannot be ruled out. Thus the results question the importance of mental stress mechanisms in the causation of regional pain related to repetitive work. However, the findings should be interpreted...

[Developmental changes in reading ability of Japanese elementary school children--analysis of 4 kana reading tasks].

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Kobayashi, Tomoka; Inagaki, Masumi; Gunji, Atsuko; Yatabe, Kiyomi; Kaga, Makiko; Goto, Takaaki; Koike, Toshihide; Wakamiya, Eiji; Koeda, Tatsuya

2010-01-01

Five hundred and twenty-eight Japanese elementary school children aged from 6 (Grade 1) to 12 (Grade 6) were tested for their abilities to read Hiragana characters, words, and short sentences. They were typically developing children whom the classroom teachers judged to have no problems with reading and writing in Japanese. Each child was asked to read four tasks which were written in Hiragana script: single mora reading task, four syllable non-word reading task, four syllable word reading task, and short sentence reading task. The total articulation time for reading and performance in terms of accuracy were measured for each task. Developmental changes in these variables were evaluated. The articulation time was significantly longer for the first graders, and it gradually shortened as they moved through to the upper grades in all tasks. The articulation time reached a plateau in the 4th grade for the four syllable word and short sentence reading tasks, while it did so for the single mora and four syllable non-word reading tasks in the 5th grade. The articulation times for the four syllable word and short sentence reading tasks correlated strongly. There were very few clear errors for all tasks, and the number of such errors significantly changed between the school grades only for the single mora and four syllable word reading tasks. It was noted that more than half of the children read the beginning portion of the word or phrase twice or more, in order to read it accurately, and developmental changes were also seen in this pattern of reading. This study revealed that the combination of these reading tasks may function as a screening test for reading disorders such as developmental dyslexia in children below the age of ten or eleven years old.

The effect of episodic retrieval on inhibition in task switching.

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Grange, James A; Kowalczyk, Agnieszka W; O'Loughlin, Rory

2017-08-01

Inhibition in task switching is inferred from n-2 repetition costs: the observation that ABA task switching sequences are responded to slower than CBA sequences. This is thought to reflect the persisting inhibition of Task A, which slows reactivation attempts. Mayr (2002) reported an experiment testing a critical noninhibitory account of this effect, namely episodic retrieval: If the trial parameters for Task A match across an ABA sequence, responses should be facilitated because of priming from episodic retrieval; a cost would occur if trial parameters mismatch. In a rule-switching paradigm, Mayr reported no significant difference in n-2 repetition cost when the trial parameters repeated or switched across an ABA sequence, in clear contrast to the episodic retrieval account. What remains unclear is whether successful episodic retrieval modulates the n-2 repetition cost. Across 3 experiments-including a close replication of Mayr-we find clear evidence of reduced n-2 task repetition costs when episodic retrieval is controlled. We find that the effect of episodic retrieval on the n-2 task repetition cost is increased when the cue-task relationship is made more abstract, suggesting the effect is because of interference in establishing the relevant attentional set. We also demonstrate that the episodic retrieval effect is not influenced by retrieval of low-level, perceptual, elements. Together, the data suggest the n-2 task repetition cost-typically attributable to an inhibitory mechanism-also reflects episodic retrieval effects. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Integrating the Ergonomics Techniques with Multi Criteria Decision Making as a New Approach for Risk Management: An Assessment of Repetitive Tasks -Entropy Case Study.

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Khandan, Mohammad; Nili, Majid; Koohpaei, Alireza; Mosaferchi, Saeedeh

2016-01-01

Nowadays, the health work decision makers need to analyze a huge amount of data and consider many conflicting evaluation criteria and sub-criteria. Therefore, an ergonomic evaluation in the work environment in order to the control occupational disorders is considered as the Multi Criteria Decision Making (MCDM) problem. In this study, the ergonomic risks factors, which may influence health, were evaluated in a manufacturing company in 2014. Then entropy method was applied to prioritize the different risk factors. This study was done with a descriptive-analytical approach and 13 tasks were included from total number of employees who were working in the seven halls of an ark opal manufacturing (240). Required information was gathered by the demographic questionnaire and Assessment of Repetitive Tasks (ART) method for repetitive task assessment. In addition, entropy was used to prioritize the risk factors based on the ergonomic control needs. The total exposure score based on the ART method calculated was equal to 30.07 ±12.43. Data analysis illustrated that 179 cases (74.6% of tasks) were in the high level of risk area and 13.8% were in the medium level of risk. ART- entropy results revealed that based on the weighted factors, higher value belongs to grip factor and the lowest value was related to neck and hand posture and duration. Based on the limited financial resources, it seems that MCDM in many challenging situations such as control procedures and priority approaches could be used successfully. Other MCDM methods for evaluating and prioritizing the ergonomic problems are recommended.

The Roles of Phonological Short-Term Memory and Working Memory in L2 Grammar and Vocabulary Learning

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Martin, Katherine I.; Ellis, Nick C.

2012-01-01

This study analyzed phonological short-term memory (PSTM) and working memory (WM) and their relationship with vocabulary and grammar learning in an artificial foreign language. Nonword repetition, nonword recognition, and listening span were used as memory measures. Participants learned the singular forms of vocabulary for an artificial foreign…

The Task Is Not Enough: Processing Approaches to Task-Based Performance

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Skehan, Peter; Xiaoyue, Bei; Qian, Li; Wang, Zhan

2012-01-01

This article reports on three research studies, all of which concern second language task performance. The first focuses on planning, and compares on-line and strategic planning as well as task repetition. The second study examines the role of familiarity on task performance, and compares this with conventional strategic planning. The third study…

Nonword Reading: Comparing Dual-Route Cascaded and Connectionist Dual-Process Models with Human Data

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Pritchard, Stephen C.; Coltheart, Max; Palethorpe, Sallyanne; Castles, Anne

2012-01-01

Two prominent dual-route computational models of reading aloud are the dual-route cascaded (DRC) model, and the connectionist dual-process plus (CDP+) model. While sharing similarly designed lexical routes, the two models differ greatly in their respective nonlexical route architecture, such that they often differ on nonword pronunciation. Neither…

Electrophysiology of Perception and Processing of Phonological Information as Indices of Toddlers' Language Performance

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Harwood, Vanessa; Preston, Jonathan; Grela, Bernard; Roy, Dooti; Harold, Olivia; Turcios, Jacqueline; Andrada, Kiyomi; Landi, Nicole

2017-01-01

Purpose: The toddler years are a critical period for language development and growth. We investigated how event-related potentials (ERPs) to repeated and novel nonwords are associated with clinical assessments of language in young children. In addition, nonword repetition (NWR) was used to measure phonological working memory to determine the…

Impact of cognitive and linguistic ability on gaze behavior in children with hearing impairment

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Olof eSandgren

2013-11-01

Full Text Available In order to explore verbal-nonverbal integration, we investigated the influence of cognitive and linguistic ability on gaze behavior during spoken language conversation between children with mild-to-moderate hearing impairment (HI and normal-hearing (NH peers. Ten HI-NH and ten NH-NH dyads performed a referential communication task requiring description of faces. During task performance, eye movements and speech were tracked. Cox proportional hazards regression was used to model associations between performance on cognitive and linguistic tasks and the probability of gaze to the conversational partner’s face. Analyses compare the listeners in each dyad (HI: n = 10, mean age = 12;6 years, SD = 2;0, mean better ear pure-tone average 33.0 dB HL, SD = 7.8; NH: n = 10, mean age = 13;7 years, SD = 1;11. Group differences in gaze behavior – with HI gazing more to the conversational partner than NH – remained significant despite adjustment for ability on receptive grammar, expressive vocabulary, and complex working memory. Adjustment for phonological short term memory, as measured by nonword repetition, removed group differences, revealing an interaction between group membership and nonword repetition ability. Stratified analysis showed a twofold increase of the probability of gaze-to-partner for HI with low phonological short term memory capacity, and a decreased probability for HI with high capacity, as compared to NH peers. The results revealed differences in gaze behavior attributable to performance on a phonological short term memory task. Participants with hearing impairment and low phonological short term memory capacity showed a doubled probability of gaze to the conversational partner, indicative of a visual bias. The results stress the need to look beyond the hearing impairment in diagnostics and intervention. Acknowledgment of the finding requires clinical assessment of children with hearing impairment to be supported by tasks tapping

Task conflict and proactive control: A computational theory of the Stroop task.

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Kalanthroff, Eyal; Davelaar, Eddy J; Henik, Avishai; Goldfarb, Liat; Usher, Marius

2018-01-01

The Stroop task is a central experimental paradigm used to probe cognitive control by measuring the ability of participants to selectively attend to task-relevant information and inhibit automatic task-irrelevant responses. Research has revealed variability in both experimental manipulations and individual differences. Here, we focus on a particular source of Stroop variability, the reverse-facilitation (RF; faster responses to nonword neutral stimuli than to congruent stimuli), which has recently been suggested as a signature of task conflict. We first review the literature that shows RF variability in the Stroop task, both with regard to experimental manipulations and to individual differences. We suggest that task conflict variability can be understood as resulting from the degree of proactive control that subjects recruit in advance of the Stroop stimulus. When the proactive control is high, task conflict does not arise (or is resolved very quickly), resulting in regular Stroop facilitation. When proactive control is low, task conflict emerges, leading to a slow-down in congruent and incongruent (but not in neutral) trials and thus to Stroop RF. To support this suggestion, we present a computational model of the Stroop task, which includes the resolution of task conflict and its modulation by proactive control. Results show that our model (a) accounts for the variability in Stroop-RF reported in the experimental literature, and (b) solves a challenge to previous Stroop models-their ability to account for reaction time distributional properties. Finally, we discuss theoretical implications to Stroop measures and control deficits observed in some psychopathologies. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Perceptual and Conceptual Priming of Cue Encoding in Task Switching

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Schneider, Darryl W.

2016-01-01

Transition effects in task-cuing experiments can be partitioned into task switching and cue repetition effects by using multiple cues per task. In the present study, the author shows that cue repetition effects can be partitioned into perceptual and conceptual priming effects. In 2 experiments, letters or numbers in their uppercase/lowercase or…

Word and Nonword Processing without Meaning Support in Korean-Speaking Children with and without Hyperlexia

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Lee, Sung Hee; Hwang, Mina

2015-01-01

Hyperlexia is a syndrome of reading without meaning in individuals who otherwise have pronounced cognitive and language deficits. The present study investigated the quality of word representation and the effects of deficient semantic processing on word and nonword reading of Korean children with hyperlexia; their performances were compared to…

Risk of shoulder tendinitis in relation to shoulder loads in monotonous repetitive work

DEFF Research Database (Denmark)

Frost, P.; Bonde, J. P.; Mikkelsen, S.

2002-01-01

BACKGROUND: Few studies relate the occurrence of shoulder disorders to quantified ergonomic exposures. This study evaluates the hypothesis that shoulder loads in repetitive work might contribute to the occurrence of shoulder tendinitis. METHODS: This is a cross-sectional study of 1961 workers...... in repetitive work and 782 referents. Shoulder loads were quantified at task level and measures of exposures were assigned based on task distribution. Symptoms in combination with clinical criteria defined shoulder tendinitis. RESULTS: The prevalence of shoulder tendinitis was higher among exposed workers...

Inflectional Morphology and Dyslexia: Italian Children's Performance in a Nonword Pluralization Task

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Vender, Maria; Mantione, Federica; Savazzi, Silvia; Delfitto, Denis; Melloni, Chiara

2017-01-01

In this study, we present the results of an original experimental protocol designed to assess the performance in a pluralization task of 52 Italian children divided into two groups: 24 children with developmental dyslexia (mean age 10.0 years old) and 28 typically developing children (mean age 9.11 years old). Our task, inspired by Berko's Wug…

Subjective duration distortions mirror neural repetition suppression.

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Pariyadath, Vani; Eagleman, David M

2012-01-01

Subjective duration is strongly influenced by repetition and novelty, such that an oddball stimulus in a stream of repeated stimuli appears to last longer in duration in comparison. We hypothesize that this duration illusion, called the temporal oddball effect, is a result of the difference in expectation between the oddball and the repeated stimuli. Specifically, we conjecture that the repeated stimuli contract in duration as a result of increased predictability; these duration contractions, we suggest, result from decreased neural response amplitude with repetition, known as repetition suppression. Participants viewed trials consisting of lines presented at a particular orientation (standard stimuli) followed by a line presented at a different orientation (oddball stimulus). We found that the size of the oddball effect correlates with the number of repetitions of the standard stimulus as well as the amount of deviance from the oddball stimulus; both of these results are consistent with a repetition suppression hypothesis. Further, we find that the temporal oddball effect is sensitive to experimental context--that is, the size of the oddball effect for a particular experimental trial is influenced by the range of duration distortions seen in preceding trials. Our data suggest that the repetition-related duration contractions causing the oddball effect are a result of neural repetition suppression. More generally, subjective duration may reflect the prediction error associated with a stimulus and, consequently, the efficiency of encoding that stimulus. Additionally, we emphasize that experimental context effects need to be taken into consideration when designing duration-related tasks.

Subjective duration distortions mirror neural repetition suppression.

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Vani Pariyadath

Full Text Available Subjective duration is strongly influenced by repetition and novelty, such that an oddball stimulus in a stream of repeated stimuli appears to last longer in duration in comparison. We hypothesize that this duration illusion, called the temporal oddball effect, is a result of the difference in expectation between the oddball and the repeated stimuli. Specifically, we conjecture that the repeated stimuli contract in duration as a result of increased predictability; these duration contractions, we suggest, result from decreased neural response amplitude with repetition, known as repetition suppression.Participants viewed trials consisting of lines presented at a particular orientation (standard stimuli followed by a line presented at a different orientation (oddball stimulus. We found that the size of the oddball effect correlates with the number of repetitions of the standard stimulus as well as the amount of deviance from the oddball stimulus; both of these results are consistent with a repetition suppression hypothesis. Further, we find that the temporal oddball effect is sensitive to experimental context--that is, the size of the oddball effect for a particular experimental trial is influenced by the range of duration distortions seen in preceding trials.Our data suggest that the repetition-related duration contractions causing the oddball effect are a result of neural repetition suppression. More generally, subjective duration may reflect the prediction error associated with a stimulus and, consequently, the efficiency of encoding that stimulus. Additionally, we emphasize that experimental context effects need to be taken into consideration when designing duration-related tasks.

Postural reconfiguration and cycle-to-cycle variability in patients with work-related musculoskeletal disorders compared to healthy controls and in relation to pain emerging during a repetitive movement task.

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Longo, Alessia; Meulenbroek, Ruud; Haid, Thomas; Federolf, Peter

2018-05-01

Movement variability in sustained repetitive tasks is an important factor in the context of work-related musculoskeletal disorders. While a popular hypothesis suggests that movement variability can prevent overuse injuries, pain evolving during task execution may also cause variability. The aim of the current study was to investigate, first, differences in movement behavior between volunteers with and without work-related pain and, second, the influence of emerging pain on movement variability. Upper-body 3D kinematics were collected as 22 subjects with musculoskeletal disorders and 19 healthy volunteers performed a bimanual repetitive tapping task with a self-chosen and a given rhythm. Three subgroups were formed within the patient group according to the level of pain the participants experienced during the task. Principal component analysis was applied to 30 joint angle coordinates to characterize in a combined analysis the movement variability associated with reconfigurations of the volunteers' postures and the cycle-to-cycle variability that occurred during the execution of the task. Patients with no task-related pain showed lower cycle-to-cycle variability compared to healthy controls. Findings also indicated an increase in movement variability as pain emerged, manifesting both as frequent postural changes and large cycle-to-cycle variability. The findings suggested a relationship between work-related musculoskeletal disorders and movement variability but further investigation is needed on this issue. Additionally, the findings provided clear evidence that pain increased motor variability. Postural reconfigurations and cycle-to-cycle variability should be considered jointly when investigating movement variability and musculoskeletal disorders. Copyright © 2018 Elsevier Ltd. All rights reserved.

N-2 repetition leads to a cost within working memory and a benefit outside it.

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Kessler, Yoav

2018-03-15

Removal has been suggested to play a key role in controlling the contents of working memory. The present study examined the aftereffects of removal in a working memory updating task. Participants performed the reference-back paradigm, a version of the n-back task that is composed of two trial types: reference trials that required working memory updating and comparison trials that did not require updating. N-2 repetition effects-the difference in performance between trials that presented the same stimulus as the one presented two trials before (ABA sequences) and trials in which the stimulus differed from the two previous stimuli (ABC sequences)-were examined. In two experiments, n-2 repetition costs were observed within sequences of reference trials, while n-2 repetition benefits were observed within sequences of comparison trials. This pattern suggests that removal takes place during working memory updating. Furthermore, automatic formation and updating of representation outside working memory, which takes place in comparison trials and gives rise to n-2 repetition benefits, does not involve removal. Removal, demonstrated by phenomena such as n-2 repetition costs, is therefore proposed to be a marker for the utilization of working memory within a given task. © 2018 New York Academy of Sciences.

Cortical activity and children's rituals, habits and other repetitive behavior: a visual P300 study.

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Evans, David W; Maliken, Ashley

2011-10-10

This study examines the link between children's repetitive, ritualistic, behavior and cortical brain activity. Twelve typically developing children between the ages of 6 and 12 years were administered two visual P300, oddball tasks with a 32-electrode electroencephalogram (EEG) system. One of the oddball tasks was specifically designed to reflect sensitivity to asymmetry, a phenomenon common in children and in a variety of disorders involving compulsive behavior. Parents completed the Childhood Routines Inventory. Children's repetitive, compulsive-like behaviors were strongly associated with faster processing of an asymmetrical target stimulus, even when accounting for their P300 latencies on a control task. The research punctuates the continuity between observed brain-behavior links in clinical disorders such as OCD and autism spectrum disorders, and normative variants of repetitive behavior. Copyright © 2011 Elsevier B.V. All rights reserved.

Contextual control over task-set retrieval.

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Crump, Matthew J C; Logan, Gordon D

2010-11-01

Contextual cues signaling task likelihood or the likelihood of task repetition are known to modulate the size of switch costs. We follow up on the finding by Leboe, Wong, Crump, and Stobbe (2008) that location cues predictive of the proportion of switch or repeat trials modulate switch costs. Their design employed one cue per task, whereas our experiment employed two cues per task, which allowed separate assessment of modulations to the cue-repetition benefit, a measure of lower level cue-encoding processes, and to the task-alternation cost, a measure of higher level processes representing task-set information. We demonstrate that location information predictive of switch proportion modulates performance at the level of task-set representations. Furthermore, we demonstrate that contextual control occurs even when subjects are unaware of the associations between context and switch likelihood. We discuss the notion that contextual information provides rapid, unconscious control over the extent to which prior task-set representations are retrieved in the service of guiding online performance.

Limitations of the Dual-Process-Theory regarding the Writing of Words and Non-Words to Dictation

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Tucha, Oliver; Trumpp, Christian; Lange, Klaus W.

2004-01-01

It is generally assumed that the lexical and phonological systems are involved in writing to dictation. In an experiment concerned with the writing of words and non-words to dictation, the handwriting of female students was registered using a digitising tablet. The data contradict the assumption that the phonological system represents an alexical…

A chain-retrieval model for voluntary task switching.

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Vandierendonck, André; Demanet, Jelle; Liefooghe, Baptist; Verbruggen, Frederick

2012-09-01

To account for the findings obtained in voluntary task switching, this article describes and tests the chain-retrieval model. This model postulates that voluntary task selection involves retrieval of task information from long-term memory, which is then used to guide task selection and task execution. The model assumes that the retrieved information consists of acquired sequences (or chains) of tasks, that selection may be biased towards chains containing more task repetitions and that bottom-up triggered repetitions may overrule the intended task. To test this model, four experiments are reported. In Studies 1 and 2, sequences of task choices and the corresponding transition sequences (task repetitions or switches) were analyzed with the help of dependency statistics. The free parameters of the chain-retrieval model were estimated on the observed task sequences and these estimates were used to predict autocorrelations of tasks and transitions. In Studies 3 and 4, sequences of hand choices and their transitions were analyzed similarly. In all studies, the chain-retrieval model yielded better fits and predictions than statistical models of event choice. In applications to voluntary task switching (Studies 1 and 2), all three parameters of the model were needed to account for the data. When no task switching was required (Studies 3 and 4), the chain-retrieval model could account for the data with one or two parameters clamped to a neutral value. Implications for our understanding of voluntary task selection and broader theoretical implications are discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

Risk factors for hand-wrist disorders in repetitive work

DEFF Research Database (Denmark)

Thomsen, J. F.; Mikkelsen, S.; Andersen, JH

2007-01-01

OBJECTIVES: To identify the risk of hand-wrist disorders related to repetitive movements, use of hand force and wrist position in repetitive monotonous work. METHODS: Using questionnaires and physical examinations, the prevalence and incidence of hand-wrist pain and possible extensor tendonitis...... (wrist pain and palpation tenderness) were determined in 3123 employees in 19 industrial settings. With the use of questionnaires and video recordings of homogenous work tasks number of wrist movements, hand force requirements and wrist position were analysed as risk factors for hand-wrist disorders......, controlling for potential personal and psychosocial confounders. All participants were re-examined three times during a follow-up period of three years. RESULTS: Force but not repetition and position was related to hand-wrist pain and possible tendonitis in the baseline analyses showing an exposure...

Time of Day Does Not Modulate Improvements in Motor Performance following a Repetitive Ballistic Motor Training Task

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Sale, Martin V.; Ridding, Michael C.; Nordstrom, Michael A.

2013-01-01

Repetitive performance of a task can result in learning. The neural mechanisms underpinning such use-dependent plasticity are influenced by several neuromodulators. Variations in neuromodulator levels may contribute to the variability in performance outcomes following training. Circulating levels of the neuromodulator cortisol change throughout the day. High cortisol levels inhibit neuroplasticity induced with a transcranial magnetic stimulation (TMS) paradigm that has similarities to use-dependent plasticity. The present study investigated whether performance changes following a motor training task are modulated by time of day and/or changes in endogenous cortisol levels. Motor training involving 30 minutes of repeated maximum left thumb abduction was undertaken by twenty-two participants twice, once in the morning (8 AM) and once in the evening (8 PM) on separate occasions. Saliva was assayed for cortisol concentration. Motor performance, quantified by measuring maximum left thumb abduction acceleration, significantly increased by 28% following training. Neuroplastic changes in corticomotor excitability of abductor pollicis brevis, quantified with TMS, increased significantly by 23% following training. Training-related motor performance improvements and neuroplasticity were unaffected by time of day and salivary cortisol concentration. Although similar neural elements and processes contribute to motor learning, training-induced neuroplasticity, and TMS-induced neuroplasticity, our findings suggest that the influence of time of day and cortisol differs for these three interventions. PMID:23577271

Time of Day Does Not Modulate Improvements in Motor Performance following a Repetitive Ballistic Motor Training Task

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Martin V. Sale

2013-01-01

Full Text Available Repetitive performance of a task can result in learning. The neural mechanisms underpinning such use-dependent plasticity are influenced by several neuromodulators. Variations in neuromodulator levels may contribute to the variability in performance outcomes following training. Circulating levels of the neuromodulator cortisol change throughout the day. High cortisol levels inhibit neuroplasticity induced with a transcranial magnetic stimulation (TMS paradigm that has similarities to use-dependent plasticity. The present study investigated whether performance changes following a motor training task are modulated by time of day and/or changes in endogenous cortisol levels. Motor training involving 30 minutes of repeated maximum left thumb abduction was undertaken by twenty-two participants twice, once in the morning (8 AM and once in the evening (8 PM on separate occasions. Saliva was assayed for cortisol concentration. Motor performance, quantified by measuring maximum left thumb abduction acceleration, significantly increased by 28% following training. Neuroplastic changes in corticomotor excitability of abductor pollicis brevis, quantified with TMS, increased significantly by 23% following training. Training-related motor performance improvements and neuroplasticity were unaffected by time of day and salivary cortisol concentration. Although similar neural elements and processes contribute to motor learning, training-induced neuroplasticity, and TMS-induced neuroplasticity, our findings suggest that the influence of time of day and cortisol differs for these three interventions.

Understanding work related musculoskeletal pain: does repetitive work cause stress symptoms?

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Bonde, J P; Mikkelsen, S; Andersen, J H; Fallentin, N; Baelum, J; Svendsen, S W; Thomsen, J F; Frost, P; Kaergaard, A

2005-01-01

Pain in the neck and upper extremity is reported with high frequency in repetitive work. Mechanical overload of soft tissues seems a plausible mechanism, but psychological factors have received considerable attention during the past decade. If psychological factors are important for development of regional pain in repetitive work, stress symptoms would likely be on the causal path. To examine whether objective measures of repetitive monotonous work are related to occurrence and development of stress symptoms. In 1994-95, 2033 unskilled workers with continuous repetitive work and 813 workers with varied work were enrolled. Measures of repetitiveness and force requirements were quantified using video observations to obtain individual exposure estimates. Stress symptoms were recorded at baseline and after approximately one, two, and three years by the Setterlind Stress Profile Inventory. Repetitive work, task cycle time, and quantified measures of repetitive upper extremity movements including force requirements were not related to occurrence of stress symptoms at baseline or development of stress symptoms during three years of follow up. The findings do not indicate that repetitive work is associated with stress symptoms, but small effects cannot be ruled out. Thus the results question the importance of mental stress mechanisms in the causation of regional pain related to repetitive work. However, the findings should be interpreted with caution because the stress inventory has not been validated against a gold standard.

Acute Alcohol Effects on Repetition Priming and Word Recognition Memory with Equivalent Memory Cues

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Ray, Suchismita; Bates, Marsha E.

2006-01-01

Acute alcohol intoxication effects on memory were examined using a recollection-based word recognition memory task and a repetition priming task of memory for the same information without explicit reference to the study context. Memory cues were equivalent across tasks; encoding was manipulated by varying the frequency of occurrence (FOC) of words…

Spared behavioral repetition effects in Alzheimer's disease linked to an altered neural mechanism at posterior cortex.

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Broster, Lucas S; Li, Juan; Wagner, Benjamin; Smith, Charles D; Jicha, Gregory A; Schmitt, Frederick A; Munro, Nancy; Haney, Ryan H; Jiang, Yang

2018-02-20

Individuals with dementia of the Alzheimer type (AD) classically show disproportionate impairment in measures of working memory, but repetition learning effects are relatively preserved. As AD affects brain regions implicated in both working memory and repetition effects, the neural basis of this discrepancy is poorly understood. We hypothesized that the posterior repetition effect could account for this discrepancy due to the milder effects of AD at visual cortex. Participants with early AD, amnestic mild cognitive impairment (MCI), and healthy controls performed a working memory task with superimposed repetition effects while electroencephalography was collected to identify possible neural mechanisms of preserved repetition effects. Participants with AD showed preserved behavioral repetition effects and a change in the posterior repetition effect. Visual cortex may play a role in maintained repetition effects in persons with early AD.

Physiological responses to four hours of low-level repetitive work

DEFF Research Database (Denmark)

Garde, A Helene; Hansen, Åse Marie; Jensen, Bente R

2003-01-01

OBJECTIVES: The study investigated physiological responses to 4 hours of standardized low-level repetitive work. It was hypothesized that accumulative effects not observed after 1 hour could be found after 4 hours of repetitive work. METHODS: Ten healthy women performed intermittent (5 seconds + 5...... muscle activity during a mental reference task with low exerted force indicated attention-related muscle activity. Finally, it was indicated that repetitive work including high demands for attention is performed at the expense of the precision of the exerted force....... seconds) handgrip contractions at 10% of the maximal voluntary contraction combined with mental demands for concentration and attention. Muscle activity in the working forearm muscles, cardiovascular responses, and concentrations of biomarkers in biological fluids were recorded along with exerted force...

The relationship between phonological short-term memory, receptive vocabulary, and fast mapping in children with specific language impairment.

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Jackson, Emily; Leitao, Suze; Claessen, Mary

2016-01-01

Children with specific language impairment (SLI) often experience word-learning difficulties, which are suggested to originate in the early stage of word learning: fast mapping. Some previous research indicates significantly poorer fast mapping capabilities in children with SLI compared with typically developing (TD) counterparts, with a range of methodological factors impacting on the consistency of this finding. Research has explored key issues that might underlie fast mapping difficulties in children with SLI, with strong theoretical support but little empirical evidence for the role of phonological short-term memory (STM). Additionally, further research is required to explore the influence of receptive vocabulary on fast mapping capabilities. Understanding the factors associated with fast mapping difficulties that are experienced by children with SLI may lead to greater theoretically driven word-learning intervention. To investigate whether children with SLI demonstrate significant difficulties with fast mapping, and to explore the related factors. It was hypothesized that children with SLI would score significantly lower on a fast mapping production task compared with TD children, and that phonological STM and receptive vocabulary would significantly predict fast mapping production scores in both groups of children. Twenty-three children with SLI (mean = 64.39 months, SD = 4.10 months) and 26 TD children (mean = 65.92 months, SD = 2.98) were recruited from specialist language and mainstream schools. All participants took part in a unique, interactive fast-mapping task whereby nine novel objects with non-word labels were presented and production accuracy was assessed. A non-word repetition test and the Peabody Picture Vocabulary Test-Fourth Edition (PPVT-IV) were also administered as measures of phonological STM capacity and receptive vocabulary, respectively. Results of the fast-mapping task indicated that children with SLI had significantly poorer fast

Translation of Syntactic Repetitions as Formal-Aesthetic Marker in Das Brot

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Rosyidah

2017-03-01

Full Text Available Translating repetition as a formal-aesthetic marker in a literary text is a hard task and challenge for translators. The topic of this study is translation of syntactic repetition as formal-aesthetic marker in literary text. The problems examined include: (1 the syntactic repetitions in the source text and (2 the strategies to translate these repetitions carried out by the students. This is a case study with a qualitative approach which is aimed to describe the syntactic repetitions as formal aesthetic markers in the German short story Das Brot written by Wolfgang Borchert and to explain the strategies used by Indonesian students to translate the syntactic repetitions. The research data are repetitive sentences gained from the German short story and from the translated versions done by 60 students. The analysis was carried out interactively and sociosemiotically. The results show that there were repetitions at the sentence level including sentence parts, sentences and content repetition in the source text. The strategies used by the students to translate the repetitions of sentence part and sentence were exact preservation and modified preservation with reduction, implicitation and addition of extra words, avoidance with deletion, explicitation, implicitation, nominalization, and synonymy. In the meantime, content repetitions were translated using the strategy of exact preservation and preservation with modification by adding extra words and using role-based terms of address. Thus, the results lead to two new variations of modified preservation, namely preservation by adding extra words and by changing addressing terms and one new variation of avoidance that is explicitation.

LANGUAGE REPETITION AND SHORT-TERM MEMORY: AN INTEGRATIVE FRAMEWORK

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Steve eMajerus

2013-07-01

Full Text Available Short-term maintenance of verbal information is a core factor of language repetition, especially when reproducing multiple or unfamiliar stimuli. Many models of language processing locate the verbal short-term maintenance function in the left posterior superior temporo-parietal area and its connections with the inferior frontal gyrus. However, research in the field of short-term memory has implicated bilateral fronto-parietal networks, involved in attention and serial order processing, as being critical for the maintenance and reproduction of verbal sequences. We present here an integrative framework aimed at bridging research in the language processing and short-term memory fields. This framework considers verbal short-term maintenance as an emergent function resulting from synchronized and integrated activation in dorsal and ventral language processing networks as well as fronto-parietal attention and serial order processing networks. To-be-maintained item representations are temporarily activated in the dorsal and ventral language processing networks, novel phoneme and word serial order information is proposed to be maintained via a right fronto-parietal serial order processing network, and activation in these different networks is proposed to be coordinated and maintained via a left fronto-parietal attention processing network. This framework provides new perspectives for our understanding of information maintenance at the nonword-, word- and sentence-level as well as of verbal maintenance deficits in case of brain injury.

Language repetition and short-term memory: an integrative framework.

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Majerus, Steve

2013-01-01

Short-term maintenance of verbal information is a core factor of language repetition, especially when reproducing multiple or unfamiliar stimuli. Many models of language processing locate the verbal short-term maintenance function in the left posterior superior temporo-parietal area and its connections with the inferior frontal gyrus. However, research in the field of short-term memory has implicated bilateral fronto-parietal networks, involved in attention and serial order processing, as being critical for the maintenance and reproduction of verbal sequences. We present here an integrative framework aimed at bridging research in the language processing and short-term memory fields. This framework considers verbal short-term maintenance as an emergent function resulting from synchronized and integrated activation in dorsal and ventral language processing networks as well as fronto-parietal attention and serial order processing networks. To-be-maintained item representations are temporarily activated in the dorsal and ventral language processing networks, novel phoneme and word serial order information is proposed to be maintained via a right fronto-parietal serial order processing network, and activation in these different networks is proposed to be coordinated and maintained via a left fronto-parietal attention processing network. This framework provides new perspectives for our understanding of information maintenance at the non-word-, word- and sentence-level as well as of verbal maintenance deficits in case of brain injury.

Relative Contributions of the Dorsal vs. Ventral Speech Streams to Speech Perception are Context Dependent: a lesion study

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Corianne Rogalsky

2014-04-01

, (iii two sentence comprehension tasks (sentence-picture matching, plausibility judgments, and (iv two sensory-motor tasks (a non-word repetition task and BDAE repetition subtest. Our results indicate that the neural bases of speech perception are task-dependent. The syllable discrimination and sensory-motor tasks all identified a dorsal temporal-parietal voxel cluster, including area Spt, primary auditory and somatosensory cortex. Conversely, the auditory comprehension task identified left mid-temporal regions. This suggest that syllable discrimination deficits do not stem from impairments in the perceptual analysis of speech sounds but rather involve temporary maintenance of the stimulus trace and/or the similarity comparison process. The ventral stream (anterior and posterior clusters in the superior and middle temporal gyri, were associated with both sentence tasks. However, the dorsal stream’s involvement was more selective: inferior frontal regions were identified in the sentence–to-picture matching task, not the semantic plausibility task. Within the sentence-to-picture matching task, these inferior frontal regions were only identified by the trials with the most difficult sentences. This suggests that the dorsal stream’s contribution to sentence comprehension is not driven by perception per se. These initial findings highlight the task-dependent nature of speech processing, challenge claims regarding any specific motor region being critical for speech perception, and refute the notion that speech perception relies on dorsal stream auditory-motor systems.

Early Morphological Productivity in Hungarian: Evidence from Sentence Repetition and Elicited Production

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Gabor, Balint; Lukacs, Agnes

2012-01-01

This paper investigates early productivity of morpheme use in Hungarian children aged between 2 ; 1 and 5 ; 3. Hungarian has a rich morphology which is the core marker of grammatical functions. A new method is introduced using the novel word paradigm in a sentence repetition task with masked inflections (i.e. a disguised elicited production task).…

Autism and exergaming: effects on repetitive behaviors and cognition

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Anderson-Hanley C

2011-09-01

Full Text Available Cay Anderson-Hanley, Kimberly Tureck, Robyn L Schneiderman Department of Psychology, Union College, Schenectady, NY, USA Abstract: Autism is a neurodevelopmental disorder that leads to impairment in social skills and delay in language development, and results in repetitive behaviors and restricted interests that impede academic and social involvement. Physical exercise has been shown to decrease repetitive behaviors in autistic children and improve cognitive function across the life-span. Exergaming combines physical and mental exercise simultaneously by linking physical activity movements to video game control and may yield better compliance with exercise. In this investigation, two pilot studies explored the potential behavioral and cognitive benefits of exergaming. In Pilot I, twelve children with autism spectrum disorders completed a control task and an acute bout of Dance Dance Revolution (DDR; in Pilot II, ten additional youths completed an acute bout of cyber cycling. Repetitive behaviors and executive function were measured before and after each activity. Repetitive behaviors significantly decreased, while performance on Digits Backwards improved following the exergaming conditions compared with the control condition. Additional research is needed to replicate these findings, and to explore the application of exergaming for the management of behavioral disturbance and to increase cognitive control in children on the autism spectrum. Keywords: autism, repetitive behaviors, exergaming, exercise, executive function

Repetitive Stress Injuries

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... Safe Videos for Educators Search English Español Repetitive Stress Injuries KidsHealth / For Teens / Repetitive Stress Injuries What's ... t had any problems since. What Are Repetitive Stress Injuries? Repetitive stress injuries (RSIs) are injuries that ...

Target-to-Target Repetition Cost and Location Negative Priming Are Dissociable: Evidence for Different Mechanisms

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Chao, Hsuan-Fu

2011-01-01

In a location-selection task, the repetition of a prior distractor location as the target location would slow down the response. This effect is termed the location negative priming (NP) effect. Recently, it has been demonstrated that repetition of a prior target location as the current target location would also slow down response. Because such…

The use of digit and sentence repetition in the identification of ...

African Journals Online (AJOL)

Kate H

value to child language researchers and speech-language therapists. .... 1801), short term memory of persons with dyslexia (Roach and Hogben ..... The results of the pilot study were used to determine how long the repetition tasks took to.

Cross-linguistic and cross-cultural effects on verbal working memory and vocabulary: testing language-minority children with an immigrant background.

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de Abreu, Pascale M J Engel; Baldassi, Martine; Puglisi, Marina L; Befi-Lopes, Debora M

2013-04-01

In this study, the authors explored the impact of test language and cultural status on vocabulary and working memory performance in multilingual language-minority children. Twenty 7-year-old Portuguese-speaking immigrant children living in Luxembourg completed several assessments of first (L1)- and second-language (L2) vocabulary (comprehension and production), executive-loaded working memory (counting recall and backward digit recall), and verbal short-term memory (digit recall and nonword repetition). Cross-linguistic task performance was compared within individuals. The language-minority children were also compared with multilingual language-majority children from Luxembourg and Portuguese-speaking monolinguals from Brazil without an immigrant background matched on age, sex, socioeconomic status, and nonverbal reasoning. Results showed that (a) verbal working memory measures involving numerical memoranda were relatively independent of test language and cultural status; (b) language status had an impact on the repetition of high- but not on low-wordlike L2 nonwords; (c) large cross-linguistic and cross-cultural effects emerged for productive vocabulary; (d) cross-cultural effects were less pronounced for vocabulary comprehension with no differences between groups if only L1 words relevant to the home context were considered. The study indicates that linguistic and cognitive assessments for language-minority children require careful choice among measures to ensure valid results. Implications for testing culturally and linguistically diverse children are discussed.

Individual differences in phonological learning and verbal STM span.

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Service, Elisabet; Maury, Sini; Luotoniemi, Emilia

2007-07-01

A relationship between phonological short-term memory tasks (e.g., nonword repetition, digit span) and vocabulary learning in both experimental and real-life conditions has been reported in numerous studies. A mechanism that would explain this correlation is, however, not known. The present study explores the possibility that it is the quality of phonological representations that affects both short-term recall and long-term learning of novel wordlike items. In Experiment 1, groups with relatively good and poor span for pseudowords were established. The good group was found to perform better at explicit memory tasks tapping the incidental learning of a limited stimulus pool used in an auditory immediate serial pseudoword recall task. In Experiment 2, the results of Experiment 1 were replicated when experience of correct recall was controlled. In Experiment 3, the immediate recall performance of the good group was found to benefit more than that of the poor group from syllable repetition within stimulus pools. It is concluded that the efficiency of a process that creates phonological representations is related both to short-term capacity for verbal items, and to long-term phonological learning of the structure of novel phonological items.

Incremental learning of perceptual and conceptual representations and the puzzle of neural repetition suppression.

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Gotts, Stephen J

2016-08-01

Incremental learning models of long-term perceptual and conceptual knowledge hold that neural representations are gradually acquired over many individual experiences via Hebbian-like activity-dependent synaptic plasticity across cortical connections of the brain. In such models, variation in task relevance of information, anatomic constraints, and the statistics of sensory inputs and motor outputs lead to qualitative alterations in the nature of representations that are acquired. Here, the proposal that behavioral repetition priming and neural repetition suppression effects are empirical markers of incremental learning in the cortex is discussed, and research results that both support and challenge this position are reviewed. Discussion is focused on a recent fMRI-adaptation study from our laboratory that shows decoupling of experience-dependent changes in neural tuning, priming, and repetition suppression, with representational changes that appear to work counter to the explicit task demands. Finally, critical experiments that may help to clarify and resolve current challenges are outlined.

Working memory capacity predicts conflict-task performance.

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Gulbinaite, Rasa; Johnson, Addie

2014-01-01

The relationship between the ability to maintain task goals and working memory capacity (WMC) is firmly established, but evidence for WMC-related differences in conflict processing is mixed. We investigated whether WMC (measured using two complex-span tasks) mediates differences in adjustments of cognitive control in response to conflict. Participants performed a Simon task in which congruent and incongruent trials were equiprobable, but in which the proportion of congruency repetitions (congruent trials followed by congruent trials or incongruent trials followed by incongruent trials) and thus the need for trial-by-trial adjustments in cognitive control varied by block. The overall Simon effect did not depend on WMC capacity. However, for the low-WMC participants the Simon effect decreased as the proportion of congruency repetitions decreased, whereas for the high- and average-WMC participants it was relatively constant across conditions. Distribution analysis of the Simon effect showed more evidence for the inhibition of stimulus location in the low- than in the high-WMC participants, especially when the proportion of congruency repetitions was low. We hypothesize that low-WMC individuals exhibit more interference from task-irrelevant information due to weaker preparatory control prior to stimulus presentation and, thus, stronger reliance on reactive recruitment of cognitive control.

Autism and exergaming: effects on repetitive behaviors and cognition.

Science.gov (United States)

Anderson-Hanley, Cay; Tureck, Kimberly; Schneiderman, Robyn L

2011-01-01

Autism is a neurodevelopmental disorder that leads to impairment in social skills and delay in language development, and results in repetitive behaviors and restricted interests that impede academic and social involvement. Physical exercise has been shown to decrease repetitive behaviors in autistic children and improve cognitive function across the life-span. Exergaming combines physical and mental exercise simultaneously by linking physical activity movements to video game control and may yield better compliance with exercise. In this investigation, two pilot studies explored the potential behavioral and cognitive benefits of exergaming. In Pilot I, twelve children with autism spectrum disorders completed a control task and an acute bout of Dance Dance Revolution (DDR); in Pilot II, ten additional youths completed an acute bout of cyber cycling. Repetitive behaviors and executive function were measured before and after each activity. Repetitive behaviors significantly decreased, while performance on Digits Backwards improved following the exergaming conditions compared with the control condition. Additional research is needed to replicate these findings, and to explore the application of exergaming for the management of behavioral disturbance and to increase cognitive control in children on the autism spectrum.

BOLD repetition decreases in object-responsive ventral visual areas depend on spatial attention.

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Eger, E; Henson, R N A; Driver, J; Dolan, R J

2004-08-01

Functional imaging studies of priming-related repetition phenomena have become widely used to study neural object representation. Although blood oxygenation level-dependent (BOLD) repetition decreases can sometimes be observed without awareness of repetition, any role for spatial attention in BOLD repetition effects remains largely unknown. We used fMRI in 13 healthy subjects to test whether BOLD repetition decreases for repeated objects in ventral visual cortices depend on allocation of spatial attention to the prime. Subjects performed a size-judgment task on a probe object that had been attended or ignored in a preceding prime display of 2 lateralized objects. Reaction times showed faster responses when the probe was the same object as the attended prime, independent of the view tested (identical vs. mirror image). No behavioral effect was evident from unattended primes. BOLD repetition decreases for attended primes were found in lateral occipital and fusiform regions bilaterally, which generalized across identical and mirror-image repeats. No repetition decreases were observed for ignored primes. Our results suggest a critical role for attention in achieving visual representations of objects that lead to both BOLD signal decreases and behavioral priming on repeated presentation.

Implicit and explicit processing of kanji and kana words and non-words studied with fMRI.

Science.gov (United States)

Thuy, Dinh Ha Duy; Matsuo, Kayako; Nakamura, Kimihiro; Toma, Keiichiro; Oga, Tatsuhide; Nakai, Toshiharu; Shibasaki, Hiroshi; Fukuyama, Hidenao

2004-11-01

Using functional magnetic resonance imaging (fMRI), we investigated the implicit language processing of kanji and kana words (i.e., hiragana transcriptions of normally written kanji words) and non-words. Twelve right-handed native Japanese speakers performed size judgments for character stimuli (implicit language task for linguistic stimuli), size judgments for scrambled-character stimuli (implicit language task for non-linguistic stimuli), and lexical decisions (explicit language task). The size judgments for scrambled-kanji stimuli and scrambled-kana stimuli produced activations on the bilateral lingual gyri (BA 18), the bilateral occipitotemporal regions (BA 19/37), and the bilateral superior and inferior parietal cortices (BA 7/40). Interestingly, besides these areas, activations of the left inferior frontal region (Broca's area, BA 44/45) and the left posterior inferior temporal cortex (PITC, BA 37), which have been considered as language areas, were additionally activated during size judgment for kanji character stimuli. Size judgment for kana character stimuli also activated Broca's area, the left PITC, and the left supramarginal gyrus (SMG, BA 40). The activations of these language areas were replicated in the lexical decisions for both kanji and kana. These findings suggest that language processing of both kanji and kana scripts is obligatory to literate Japanese subjects. Moreover, comparison between the scrambled kanji and the scrambled kana showed no activation in the language areas, while greater activation in the bilateral fusiform gyri (left-side predominant) was found in kanji vs. kana comparison during the size judgment and the lexical decision. Kana minus kanji activated the left SMG during the size judgment, and Broca's area and the left middle/superior temporal junction during the lexical decision. These results probably reflect that in implicit or explicit reading of kanji words and kana words (i.e., hiragana transcriptions of kanji words

Contrasting contributions of phonological short-term memory and long-term knowledge to vocabulary learning in a foreign language.

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Masoura, Elvira V; Gathercole, Susan E

2005-01-01

The contributions of phonological short-term memory and existing foreign vocabulary knowledge to the learning of new words in a second language were compared in a sample of 40 Greek children studying English at school. The children's speed of learning new English words in a paired-associate learning task was strongly influenced by their current English vocabulary, but was independent of phonological memory skill, indexed by nonword repetition ability. However, phonological memory performance was closely linked to English vocabulary scores. The findings suggest that in learners with considerable familiarity with a second language, foreign vocabulary acquisition is mediated largely by use of existing knowledge representations.

Verbal short-term memory and vocabulary learning in polyglots.

Science.gov (United States)

Papagno, C; Vallar, G

1995-02-01

Polyglot and non-polyglot Italian subjects were given tests assessing verbal (phonological) and visuo-spatial short-term and long-term memory, general intelligence, and vocabulary knowledge in their native language. Polyglots had a superior level of performance in verbal short-term memory tasks (auditory digit span and nonword repetition) and in a paired-associate learning test, which assessed the subjects' ability to acquire new (Russian) words. By contrast, the two groups had comparable performance levels in tasks assessing general intelligence, visuo-spatial short-term memory and learning, and paired-associate learning of Italian words. These findings, which are in line with neuropsychological and developmental evidence, as well as with data from normal subjects, suggest a close relationship between the capacity of phonological memory and the acquisition of foreign languages.

Growth of verbal short-term memory of nonwords varying in phonotactic probability : A longitudinal study with monolingual and bilingual children

NARCIS (Netherlands)

Messer, Marielle H.|info:eu-repo/dai/nl/304835226; Verhagen, Josje|info:eu-repo/dai/nl/277955882; Boom, Jan|info:eu-repo/dai/nl/07472732X; Mayo, Aziza Y.|info:eu-repo/dai/nl/271313404; Leseman, Paul P M|info:eu-repo/dai/nl/070760810

2015-01-01

This study investigates the hypothesis that verbal short-term memory growth in young children can be explained by increases in long-term linguistic knowledge. To this aim, we compare children's recall of nonwords varying in phonotactic probability. If our assumption holds, there should be growth in

The Role of Reminding in the Effects of Spaced Repetitions on Cued Recall: Sufficient but Not Necessary

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Wahlheim, Christopher N.; Maddox, Geoffrey B.; Jacoby, Larry L.

2014-01-01

Three experiments examined the role of study-phase retrieval (reminding) in the effects of spaced repetitions on cued recall. Remindings were brought under task control to evaluate their effects. Participants studied 2 lists of word pairs containing 3 item types: single items that appeared once in List 2, within-list repetitions that appeared…

Exploiting Dynamics in robotic arms with repetitive tasks

NARCIS (Netherlands)

Plooij, M.C.

2015-01-01

Since the industrial revolution, machines have taken over many tasks from humans, increasing labor productivity and prosperity. In the 20th century, the introduction of robots created a second wave of automation, increasing the labor productivity even further. In order to create a third wave of

N250r and N400 ERP correlates of immediate famous face repetition are independent of perceptual load.

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Neumann, Markus F; Schweinberger, Stefan R

2008-11-06

It is a matter of considerable debate whether attention to initial stimulus presentations is required for repetition-related neural modulations to occur. Recently, it has been assumed that faces are particularly hard to ignore, and can capture attention in a reflexive manner. In line with this idea, electrophysiological evidence for long-term repetition effects of unattended famous faces has been reported. The present study investigated influences of attention to prime faces on short-term repetition effects in event-related potentials (ERPs). We manipulated attention to short (200 ms) prime presentations (S1) of task-irrelevant famous faces according to Lavie's Perceptual Load Theory. Participants attended to letter strings superimposed on face images, and identified target letters "X" vs. "N" embedded in strings of either 6 different (high load) or 6 identical (low load) letters. Letter identification was followed by probe presentations (S2), which were either repetitions of S1 faces, new famous faces, or infrequent butterflies, to which participants responded. Our ERP data revealed repetition effects in terms of an N250r at occipito-temporal regions, suggesting priming of face identification processes, and in terms of an N400 at the vertex, suggesting semantic priming. Crucially, the magnitude of these effects was unaffected by perceptual load at S1 presentation. This indicates that task-irrelevant face processing is remarkably preserved even in a demanding letter detection task, supporting recent notions of face-specific attentional resources.

A test of the orthographic recoding hypothesis

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Gaygen, Daniel E.

2003-04-01

The Orthographic Recoding Hypothesis [D. E. Gaygen and P. A. Luce, Percept. Psychophys. 60, 465-483 (1998)] was tested. According to this hypothesis, listeners recognize spoken words heard for the first time by mapping them onto stored representations of the orthographic forms of the words. Listeners have a stable orthographic representation of words, but no phonological representation, when those words have been read frequently but never heard or spoken. Such may be the case for low frequency words such as jargon. Three experiments using visually and auditorily presented nonword stimuli tested this hypothesis. The first two experiments were explicit tests of memory (old-new tests) for words presented visually. In the first experiment, the recognition of auditorily presented nonwords was facilitated when they previously appeared on a visually presented list. The second experiment was similar, but included a concurrent articulation task during a visual word list presentation, thus preventing covert rehearsal of the nonwords. The results were similar to the first experiment. The third experiment was an indirect test of memory (auditory lexical decision task) for visually presented nonwords. Auditorily presented nonwords were identified as nonwords significantly more slowly if they had previously appeared on the visually presented list accompanied by a concurrent articulation task.

Phonological Working Memory in 4-8 Year-Old Persian Children Who stutter

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Maryam Vahab

2014-12-01

Full Text Available Background: One language-related area that has recently received more attention from researchers working in the field of stuttering is phonological working memory. This article aimed to identify phonological skills of working memory in children with stuttering in comparison with normal children, and to obtain the relationship between the increase in the number of syllables in nonwords and the mean percentage of error in non-word repetition in both groups, then to compare them with each other. Methods: Thirty children participated in the study, 15 children who stutter and 15 normal children which were matched by age, gender and socio-economic status. Cases of this study were recruited by non random convenience sampling. The research data collection was based on non-word repetition test. The test included 40 non-words. Independent t-tests and linear regression were used for data analysis. Results: Results revealed that in all cases the mean percentage of error was higher in children who stutter than normal children, but the difference was not statistically significant (P>0.05. Also the mean percentage error did not show a regular increase by increasing the number of syllables in the non-words. So that, in both groups of the study the highest mean percentage of error was related to single-syllable non-words then three-syllable and two-syllable ones. Conclusion: The results of the present research from previous researches support the view that children with stuttering may have some degree of delay and slow in phonological working memory abilities when compared to normal children. It is proposed that in future more researches could be done in more samples, in different age groups of children and adults who stutter.

Contribution of fronto-striatal regions to emotional valence and repetition under cognitive conflict.

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Chun, Ji-Won; Park, Hae-Jeong; Kim, Dai Jin; Kim, Eosu; Kim, Jae-Jin

2017-07-01

Conflict processing mediated by fronto-striatal regions may be influenced by emotional properties of stimuli. This study aimed to examine the effects of emotion repetition on cognitive control in a conflict-provoking situation. Twenty-one healthy subjects were scanned using functional magnetic resonance imaging while performing a sequential cognitive conflict task composed of emotional stimuli. The regional effects were analyzed according to the repetition or non-repetition of cognitive congruency and emotional valence between the preceding and current trials. Post-incongruence interference in error rate and reaction time was significantly smaller than post-congruence interference, particularly under repeated positive and non-repeated positive, respectively, and post-incongruence interference, compared to post-congruence interference, increased activity in the ACC, DLPFC, and striatum. ACC and DLPFC activities were significantly correlated with error rate or reaction time in some conditions, and fronto-striatal connections were related to the conflict processing heightened by negative emotion. These findings suggest that the repetition of emotional stimuli adaptively regulates cognitive control and the fronto-striatal circuit may engage in the conflict adaptation process induced by emotion repetition. Both repetition enhancement and repetition suppression of prefrontal activity may underlie the relationship between emotion and conflict adaptation. Copyright © 2017 Elsevier B.V. All rights reserved.

The role of selective attention in perceptual and affective priming

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Stone, M.; Ladd, S. L.; Gabrieli, J. D.

2000-01-01

Two kinds of perceptual priming (word identification and word fragment completion), as well as preference priming (that may rely on special affective mechanisms) were examined after participants either read or named the colors of words and nonwords at study. Participants named the colors of words more slowly than the colors of nonwords, indicating that lexical processing of the words occurred at study. Nonetheless, priming on all three tests was lower after color naming than after reading, despite evidence of lexical processing during color naming shown by slower responses to words than to nonwords. These results indicate that selective attention to (rather than the mere processing of) letter string identity at study is important for subsequent repetition priming.

Task effects on BOLD signal correlates of implicit syntactic processing

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Caplan, David

2010-01-01

BOLD signal was measured in sixteen participants who made timed font change detection judgments in visually presented sentences that varied in syntactic structure and the order of animate and inanimate nouns. Behavioral data indicated that sentences were processed to the level of syntactic structure. BOLD signal increased in visual association areas bilaterally and left supramarginal gyrus in the contrast of sentences with object- and subject-extracted relative clauses without font changes in which the animacy order of the nouns biased against the syntactically determined meaning of the sentence. This result differs from the findings in a non-word detection task (Caplan et al, 2008a), in which the same contrast led to increased BOLD signal in the left inferior frontal gyrus. The difference in areas of activation indicates that the sentences were processed differently in the two tasks. These differences were further explored in an eye tracking study using the materials in the two tasks. Issues pertaining to how parsing and interpretive operations are affected by a task that is being performed, and how this might affect BOLD signal correlates of syntactic contrasts, are discussed. PMID:20671983

GPI-repetitive control for linear systems with parameter uncertainty / variation

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John A. Cortés-Romero

2015-01-01

Full Text Available Robust repetitive control problems for uncertain linear systems have been considered by different approaches. This article proposes the use of Repetitive Control and Generalized Proportional Integral (GPI Control in a complementary fashion. The conditioning and coupling of these techniques has been done in a time discrete context. Repetitive control is a control technique, based on the internal model principle, which yields perfect asymptotic tracking and rejection of periodic signals. On the other hand, GPI control is established as a robust linear control system design technique that is able to reject structured time polynomial additive perturbation, in particular, parameter uncertainty that can be locally approximated by time polynomial signal. GPI control provides a suitable stability and robustness conditions for the proper Repetitive Control operation. A stability analysis is presented under the frequency response framework using plant samples for different parameter uncertainty conditions. We carry out some comparative stability analysis with other complementary control approaches that has been effective for this kind of task, enhancing a better robustness and an improved performance for the GPI case. Illustrative simulation examples are presented which validate the proposed approach.

Emotion-induced impairments in speeded word recognition tasks.

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Zeelenberg, René; Bocanegra, Bruno R; Pecher, Diane

2011-01-01

Recent studies show that emotional stimuli impair the identification of subsequently presented, briefly flashed stimuli. In the present study, we investigated whether emotional distractors (primes) impaired target processing when presentation of the target stimulus was not impoverished. In lexical decision, animacy decision, rhyme decision, and nonword naming, targets were presented in such a manner that they were clearly visible (i.e., targets were not masked and presented until participants responded). In all tasks taboo-sexual distractors caused a slowdown in responding to the subsequent neutral target. Our results indicate that the detrimental effects of emotional distractors are not confined to paradigms in which visibility of the target is limited. Moreover, impairments were obtained even when semantic processing of stimuli was not required.

Nonstrategic Contributions to Putatively Strategic Effects in Selective Attention Tasks

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Risko, Evan F.; Blais, Chris; Stolz, Jennifer A.; Besner, Derek

2008-01-01

Proportion compatible manipulations are often used to index strategic processes in selective attention tasks. Here, a subtle confound in proportion compatible manipulations is considered. Specifically, as the proportion of compatible trials increases, the ratio of complete repetitions and complete alternations to partial repetitions increases on…

Between-language repetition priming in antonym generation: evidence that translation-equivalent adjectives have shared conceptual representations across languages.

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Taylor, Randolph S; Francis, Wendy S

2017-03-01

Previous literature has demonstrated conceptual repetition priming across languages in bilinguals. This between-language priming effect is taken as evidence that translation equivalents have shared conceptual representations across languages. However, the vast majority of this research has been conducted using only concrete nouns as stimuli. The present experiment examined conceptual repetition priming within and between languages in adjectives, a part of speech not previously investigated in studies of bilingual conceptual representation. The participants were 100 Spanish-English bilinguals who had regular exposure to both languages. At encoding, participants performed a shallow processing task and a deep-processing task on English and Spanish adjectives. At test, they performed an antonym-generation task in English, in which the target responses were either adjectives presented at encoding or control adjectives not previously presented. The measure of priming was the response time advantage for producing repeated adjectives relative to control adjectives. Significant repetition priming was observed both within and between languages under deep, but not shallow, encoding conditions. The results indicate that the conceptual representations of adjective translation equivalents are shared across languages.

Additive effects of repetition and predictability during comprehension: evidence from event-related potentials.

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Wing-Yee Chow

Full Text Available Previous research has shown that neural responses to words during sentence comprehension are sensitive to both lexical repetition and a word's predictability in context. While previous research has often contrasted the effects of these variables (e.g. by looking at cases in which word repetition violates sentence-level constraints, little is known about how they work in tandem. In the current study we examine how recent exposure to a word and its predictability in context combine to impact lexical semantic processing. We devise a novel paradigm that combines reading comprehension with a recognition memory task, allowing for an orthogonal manipulation of a word's predictability and its repetition status. Using event-related brain potentials (ERPs, we show that word repetition and predictability have qualitatively similar and additive effects on the N400 amplitude. We propose that prior exposure to a word and predictability impact lexical semantic processing in an additive and independent fashion.

Short-term Memory in Childhood Dyslexia: Deficient Serial Order in Multiple Modalities.

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Cowan, Nelson; Hogan, Tiffany P; Alt, Mary; Green, Samuel; Cabbage, Kathryn L; Brinkley, Shara; Gray, Shelley

2017-08-01

In children with dyslexia, deficits in working memory have not been well-specified. We assessed second-grade children with dyslexia, with and without concomitant specific language impairment, and children with typical development. Immediate serial recall of lists of phonological (non-word), lexical (digit), spatial (location) and visual (shape) items were included. For the latter three modalities, we used not only standard span but also running span tasks, in which the list length was unpredictable to limit mnemonic strategies. Non-word repetition tests indicated a phonological memory deficit in children with dyslexia alone compared with those with typical development, but this difference vanished when these groups were matched for non-verbal intelligence and language. Theoretically important deficits in serial order memory in dyslexic children, however, persisted relative to matched typically developing children. The deficits were in recall of (1) spoken digits in both standard and running span tasks and (2) spatial locations, in running span only. Children with dyslexia with versus without language impairment, when matched on non-verbal intelligence, had comparable serial order memory, but differed in phonology. Because serial orderings of verbal and spatial elements occur in reading, the careful examination of order memory may allow a deeper understanding of dyslexia and its relation to language impairment. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

The relationship between executive functioning, central coherence, and repetitive behaviors in the high-functioning autism spectrum.

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South, Mikle; Ozonoff, Sally; McMahon, William M

2007-09-01

This study examined the relationship between everyday repetitive behavior (primary symptoms of autism) and performance on neuropsychological tests of executive function and central coherence (secondary symptoms). It was hypothesized that the frequency and intensity of repetitive behavior would be positively correlated with laboratory measures of cognitive rigidity and weak central coherence. Participants included 19 individuals (ages 10-19) with high-functioning autism spectrum disorders (ASD group) and 18 age- and IQ-matched typically developing controls (TD group). There was partial support in the ASD group for the link between repetitive behavior and executive performance (the Wisconsin Card Sorting Task). There was no support for a link between repetitive behavior and measures of central coherence (a Gestalt Closure test and the Embedded Figures Test). Further research on repetitive behaviors in autism may benefit from a focus on narrow behavioral and cognitive constructs rather than general categories.

Perseveration and other repetitive verbal behaviors: functional dissociations.

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Christman, Sarah S; Boutsen, Frank R; Buckingham, Hugh W

2004-11-01

This article will review types of perseveration from a neurolinguistic perspective. During the course of the article, continuous, stuck-in-set, and recurrent perseveration will be placed in contradistinction to several other types of repetitive behaviors commonly associated with neurogenic communication disorders. These include echolalia in mixed transcortical aphasia; conduite d'approche and conduite d'ecart in fluent aphasias; lexical and nonlexical automatisms in nonfluent aphasias; palilalia in neuromotor disorders, such as Parkinson's disease (PD); and sound, syllable, word, and phrase repetitions in neurogenic stuttering. When differentiating these phenomena from perseveration, it is helpful to consider the salient factors that condition observed behaviors in individual patients, such as overall speech fluency, inventory of available utterances, nature of eliciting tasks, and propositionality of responses. Information such as communication disorder diagnosis, underlying etiology, and known sites of lesion from each patient's total clinical profile may also assist with differentiation.

Direct and octave-shifted pitch matching during nonword imitations in men, women, and children.

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Peter, Beate; Foster, Bronsyn; Haas, Heather; Middleton, Kyle; McKibben, Kiersten

2015-03-01

To evaluate whether children, women, and men match the speaker's fundamental frequency (F0) during nonword imitation directly when the target F0 is within the responders' vocal ranges and at octave-shifted levels when the target is outside their vocal ranges, and to evaluate the role of a history of speech sound disorder (SSD) in the adult participants. Observational. Nonword sets spoken by a man and a woman were imitated by 14 men, 21 women, and 19 children. Approximately half of the adults and two-thirds of the children had a history of SSD. F0 in the imitations was compared with that in the targets and in the participants' nonimitated control word productions. When the target F0 was within the responders' vocal ranges, the imitations approximated the target F0. Men imitating a woman's voice approximated F0 levels one octave below the target F0. Children imitating a man's voice approximated F0 levels one octave above the target F0. Women imitating a man's voice approximated the target F0 at a ratio of 1.5 known as the perfect fifth in music. A history of SSD did not influence the results. This study replicates previous findings showing that target F0 was a salient aspect of the stimuli that was imitated along with the targets' segmental and prosodic components without explicit prompting. It is the first to show F0 convergence not only directly but also at relevant target/imitation intervals including the octave interval. Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Bilingual language processing after a lesion in the left thalamic and temporal regions. A case report with early childhood onset

International Nuclear Information System (INIS)

van Lieshout, P.; Renier, W.; Eling, P.; de Bot, K.; Slis, I.

1990-01-01

This case study concerns an 18-year-old bilingual girl who suffered a radiation lesion in the left (dominant) thalamic and temporal region when she was 4 years old. Language and memory assessment revealed deficits in auditory short-term memory, auditory word comprehension, nonword repetition, syntactic processing, word fluency, and confrontation naming tasks. Both languages (English and Dutch) were found to be affected in a similar manner, despite the fact that one language (English) was acquired before and the other (Dutch) after the period of lesion onset. Most of the deficits appear to be related to verbal (short-term) memory dysfunction. Several hypotheses of subcortical involvement in memory processes are discussed with reference to existing theories in this area

Tarefas repetitivas sob pressão temporal: os distúrbios musculoesqueléticos e o trabalho industrial Repetitive tasks under time pressure: the musculoskeletal disorders and the industrial work

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Rita de Cássia Pereira Fernandes

2010-05-01

Full Text Available Realizou-se estudo ergonômico a fim de caracterizar as tarefas repetitivas e as demandas psicossociais no trabalho industrial em empresa do ramo plástico da Região Metropolitana de Salvador (BA. Realizaram-se observações globais das tarefas nas primeiras visitas à empresa, visando conhecer a organização geral, o funcionamento da produção e os determinantes das tarefas. Observaram-se nesta etapa que as exigências temporais na execução das tarefas implicavam demandas psicossociais e demandas físicas, em especial, os movimentos repetitivos. Na segunda etapa, realizaram-se observações sistemáticas, com entrevistas simultâneas. Mediu-se a duração dos ciclos básicos das tarefas na moldagem/acabamento das embalagens e registrou-se a ocorrência de perturbações que exigiam das trabalhadoras sua regulação. Identificaram-se variabilidades do trabalho, evidenciando como são geradas as demandas extras e como as exigências cognitivas e físicas podem ser exacerbadas pela pressão temporal. A insuficiência dos meios de trabalho, as exigências temporais da gestão da produção e uma organização do trabalho caracterizada pelo baixo controle conformam uma situação em que a continuidade da produção apenas é possível à custa de hipersolicitação do corpo das trabalhadoras.An ergonomic study was carried out to characterize repetitive work and psychosocial demands at work in a plastic industry in The Greater Salvador, State of Bahia, Brazil. Global observations of tasks were preliminary carried out to investigate work organization, production organization and tasks determinants. Time requirements in tasks development involved psychosocial demands and physical demands, particularly when the latter implied very fast repetitive work. Secondly, those findings led to systematic observations with simultaneous interviews of workers. Work cycles in each task of molding/finishing plastic bags were measured by video analysis. All

Laterality of repetitive finger movement performance and clinical features of Parkinson's disease.

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Stegemöller, Elizabeth; Zaman, Andrew; MacKinnon, Colum D; Tillman, Mark D; Hass, Chris J; Okun, Michael S

2016-10-01

Impairments in acoustically cued repetitive finger movement often emerge at rates near to and above 2Hz in persons with Parkinson's Disease (PD) in which some patients move faster (hastening) and others move slower (bradykinetic). The clinical features impacting this differential performance of repetitive finger movement remain unknown. The purpose of this study was to compare repetitive finger movement performance between the more and less affected side, and the difference in clinical ratings among performance groups. Forty-one participants diagnosed with idiopathic PD completed an acoustically cued repetitive finger movement task while "on" medication. Eighteen participants moved faster, 10 moved slower, and 13 were able to maintain the appropriate rate at rates above 2Hz. Clinical measures of laterality, disease severity, and the UPDRS were obtained. There were no significant differences between the more and less affected sides regardless of performance group. Comparison of disease severity, tremor, and rigidity among performance groups revealed no significant differences. Comparison of posture and postural instability scores revealed that the participants that demonstrated hastening had worse posture and postural instability scores. Consideration of movement rate during the clinical evaluation of repetitive finger movement may provide additional insight into varying disease features in persons with PD. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of dual-task conditions on cervical spine movement variability.

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Niederer, Daniel; Vogt, Lutz; Vogel, Johanna; Banzer, Winfried

2017-09-22

The potential to accurately perform cervical movements during more challenging tasks might be of importance to prevent dysfunctional motion characteristics. Although sensorimotor function during dual-task conditions are of increasing interest in biomedical and rehabilitation research, effects of such conditions on movement consistency of the neck have not yet been investigated. In this crossover MiSpEx(Medicine in Spine Exercise)-diagnostic study, we aimed to explore differences between single and dual-task conditions on cervical movement variability. Nineteen healthy participants (9 male; 24.5 ± 3.3 y) performed 10 repetitive maximal cervical movements in (1) flexion/extension and (2) lateral flexion, during one single- and during two dual-task test conditions (cognitive, motor) in a randomised and cross-over sequence. Latter consisted of a working memory n-back task (n= 2) and a repetitive ankle movement task. Range of motion (RoM) was assessed using an external three-dimensional ultrasonic movement analysis system. Coefficient of variation (CV) for repetitive RoM was analysed for differences between conditions and controlled for variances in intra-individual movement characteristics. Friedman and post-hoc Bonferroni-adjusted confidence intervals for differences from single- to dual-task values revealed changes in CV in flexion/extension from single-task to motor dual-task (+0.02 ± 0.02 (97.5%CI: 0.01; 0.03); pdual-task condition (+0.01 ± 0.02 (97.5%CI: 0.003; 0.02)) nor for lateral flexion (p> 0.05). Pearson regression analyses revealed a linear negative (pdual-task (R=2 0.55). Results for lateral flexion are comparable, baseline CV negatively impacts differences to cognitive (R=2 0.2) and motor dual-task performance (R=2 0.76; pdual-task conditions while participants with a higher variability remained almost stable or showed a decrease. The results point toward a complex interrelationship of motion patterns and adaptation processes during challenging tasks

Repetitive transcranial magnetic stimulation over the right dorsolateral prefrontal cortex affects strategic decision-making.

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van 't Wout, Mascha; Kahn, René S; Sanfey, Alan G; Aleman, André

2005-11-07

Although decision-making is typically seen as a rational process, emotions play a role in tasks that include unfairness. Recently, activation in the right dorsolateral prefrontal cortex during offers experienced as unfair in the Ultimatum Game was suggested to subserve goal maintenance in this task. This is restricted to correlational evidence, however, and it remains unclear whether the dorsolateral prefrontal cortex is crucial for strategic decision-making. The present study used repetitive transcranial magnetic stimulation in order to investigate the causal role of the dorsolateral prefrontal cortex in strategic decision-making in the Ultimatum Game. The results showed that repetitive transcranial magnetic stimulation over the right dorsolateral prefrontal cortex resulted in an altered decision-making strategy compared with sham stimulation. We conclude that the dorsolateral prefrontal cortex is causally implicated in strategic decision-making in healthy human study participants.

Stimulus repetition and the perception of time: the effects of prior exposure on temporal discrimination, judgment, and production.

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William J Matthews

Full Text Available It has been suggested that repeated stimuli have shorter subjective duration than novel items, perhaps because of a reduction in the neural response to repeated presentations of the same object. Five experiments investigated the effects of repetition on time perception and found further evidence that immediate repetition reduces apparent duration, consistent with the idea that subjective duration is partly based on neural coding efficiency. In addition, the experiments found (a no effect of repetition on the precision of temporal discrimination, (b that the effects of repetition disappeared when there was a modest lag between presentations, (c that, across participants, the size of the repetition effect correlated with temporal discrimination, and (d that the effects of repetition suggested by a temporal production task were the opposite of those suggested by temporal judgments. The theoretical and practical implications of these results are discussed.

Repetition and Translation Shifts

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Simon Zupan

2006-06-01

Full Text Available Repetition manifests itself in different ways and at different levels of the text. The first basic type of repetition involves complete recurrences; in which a particular textual feature repeats in its entirety. The second type involves partial recurrences; in which the second repetition of the same textual feature includes certain modifications to the first occurrence. In the article; repetitive patterns in Edgar Allan Poe’s short story “The Fall of the House of Usher” and its Slovene translation; “Konec Usherjeve hiše”; are compared. The author examines different kinds of repetitive patterns. Repetitions are compared at both the micro- and macrostructural levels. As detailed analyses have shown; considerable microstructural translation shifts occur in certain types of repetitive patterns. Since these are not only occasional; sporadic phenomena; but are of a relatively high frequency; they reduce the translated text’s potential for achieving some of the gothic effects. The macrostructural textual property particularly affected by these shifts is the narrator’s experience as described by the narrative; which suffers a reduction in intensity.

Comparing Repetition Priming Effects in Words and Arithmetic Equations: Robust Priming Regardless of Color or Response Hand Change

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Ailsa Humphries

2018-01-01

Full Text Available Previous studies have shown that stimulus repetition can lead to reliable behavioral improvements. Although this repetition priming (RP effect has been reported in a number of paradigms using a variety of stimuli including words, objects, and faces, only a few studies have investigated mathematical cognition involving arithmetic computation, and no prior research has directly compared RP effects in a linguistic task with an arithmetic task. In two experiments, we used a within-subjects design to investigate and compare the magnitude of RP, and the effects of changing the color or the response hand for repeated, otherwise identical, stimuli in a word and an arithmetic categorization task. The results show that the magnitude of RP was comparable between the two tasks and that changing the color or the response hand had a negligible effect on priming in either task. These results extended previous findings in mathematical cognition. They also indicate that priming does not vary with stimulus domain. The implications of the results were discussed with reference to both facilitation of component processes and episodic memory retrieval of stimulus–response binding.

Comparing Repetition Priming Effects in Words and Arithmetic Equations: Robust Priming Regardless of Color or Response Hand Change.

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Humphries, Ailsa; Chen, Zhe; Neumann, Ewald

2017-01-01

Previous studies have shown that stimulus repetition can lead to reliable behavioral improvements. Although this repetition priming (RP) effect has been reported in a number of paradigms using a variety of stimuli including words, objects, and faces, only a few studies have investigated mathematical cognition involving arithmetic computation, and no prior research has directly compared RP effects in a linguistic task with an arithmetic task. In two experiments, we used a within-subjects design to investigate and compare the magnitude of RP, and the effects of changing the color or the response hand for repeated, otherwise identical, stimuli in a word and an arithmetic categorization task. The results show that the magnitude of RP was comparable between the two tasks and that changing the color or the response hand had a negligible effect on priming in either task. These results extended previous findings in mathematical cognition. They also indicate that priming does not vary with stimulus domain. The implications of the results were discussed with reference to both facilitation of component processes and episodic memory retrieval of stimulus-response binding.

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

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

2013-11-01

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

Roles of repetitive sequences

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Bell, G.I.

1991-12-31

The DNA of higher eukaryotes contains many repetitive sequences. The study of repetitive sequences is important, not only because many have important biological function, but also because they provide information on genome organization, evolution and dynamics. In this paper, I will first discuss some generic effects that repetitive sequences will have upon genome dynamics and evolution. In particular, it will be shown that repetitive sequences foster recombination among, and turnover of, the elements of a genome. I will then consider some examples of repetitive sequences, notably minisatellite sequences and telomere sequences as examples of tandem repeats, without and with respectively known function, and Alu sequences as an example of interspersed repeats. Some other examples will also be considered in less detail.

Understanding communicative actions: a repetitive TMS study.

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Stolk, Arjen; Noordzij, Matthijs L; Volman, Inge; Verhagen, Lennart; Overeem, Sebastiaan; van Elswijk, Gijs; Bloem, Bas; Hagoort, Peter; Toni, Ivan

2014-02-01

Despite the ambiguity inherent in human communication, people are remarkably efficient in establishing mutual understanding. Studying how people communicate in novel settings provides a window into the mechanisms supporting the human competence to rapidly generate and understand novel shared symbols, a fundamental property of human communication. Previous work indicates that the right posterior superior temporal sulcus (pSTS) is involved when people understand the intended meaning of novel communicative actions. Here, we set out to test whether normal functioning of this cerebral structure is required for understanding novel communicative actions using inhibitory low-frequency repetitive transcranial magnetic stimulation (rTMS). A factorial experimental design contrasted two tightly matched stimulation sites (right pSTS vs left MT+, i.e., a contiguous homotopic task-relevant region) and tasks (a communicative task vs a visual tracking task that used the same sequences of stimuli). Overall task performance was not affected by rTMS, whereas changes in task performance over time were disrupted according to TMS site and task combinations. Namely, rTMS over pSTS led to a diminished ability to improve action understanding on the basis of recent communicative history, while rTMS over MT+ perturbed improvement in visual tracking over trials. These findings qualify the contributions of the right pSTS to human communicative abilities, showing that this region might be necessary for incorporating previous knowledge, accumulated during interactions with a communicative partner, to constrain the inferential process that leads to action understanding. Copyright © 2013 Elsevier Ltd. All rights reserved.

Semantic and phonological contributions to short-term repetition and long-term cued sentence recall.

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Meltzer, Jed A; Rose, Nathan S; Deschamps, Tiffany; Leigh, Rosie C; Panamsky, Lilia; Silberberg, Alexandra; Madani, Noushin; Links, Kira A

2016-02-01

The function of verbal short-term memory is supported not only by the phonological loop, but also by semantic resources that may operate on both short and long time scales. Elucidation of the neural underpinnings of these mechanisms requires effective behavioral manipulations that can selectively engage them. We developed a novel cued sentence recall paradigm to assess the effects of two factors on sentence recall accuracy at short-term and long-term stages. Participants initially repeated auditory sentences immediately following a 14-s retention period. After this task was complete, long-term memory for each sentence was probed by a two-word recall cue. The sentences were either concrete (high imageability) or abstract (low imageability), and the initial 14-s retention period was filled with either an undemanding finger-tapping task or a more engaging articulatory suppression task (Exp. 1, counting backward by threes; Exp. 2, repeating a four-syllable nonword). Recall was always better for the concrete sentences. Articulatory suppression reduced accuracy in short-term recall, especially for abstract sentences, but the sentences initially recalled following articulatory suppression were retained better at the subsequent cued-recall test, suggesting that the engagement of semantic mechanisms for short-term retention promoted encoding of the sentence meaning into long-term memory. These results provide a basis for using sentence imageability and subsequent memory performance as probes of semantic engagement in short-term memory for sentences.

Hebb learning, verbal short-term memory, and the acquisition of phonological forms in children.

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Mosse, Emma K; Jarrold, Christopher

2008-04-01

Recent work using the Hebb effect as a marker for implicit long-term acquisition of serial order has demonstrated a functional equivalence across verbal and visuospatial short-term memory. The current study extends this observation to a sample of five- to six-year-olds using verbal and spatial immediate serial recall and also correlates the magnitude of Hebb learning with explicit measures of word and nonword paired-associate learning. Comparable Hebb effects were observed in both domains, but only nonword learning was significantly related to the magnitude of Hebb learning. Nonword learning was also independently related to individuals' general level of verbal serial recall. This suggests that vocabulary acquisition depends on both a domain-specific short-term memory system and a domain-general process of learning through repetition.

Sentence Repetition in Deaf Children with Specific Language Impairment in British Sign Language

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Marshall, Chloë; Mason, Kathryn; Rowley, Katherine; Herman, Rosalind; Atkinson, Joanna; Woll, Bencie; Morgan, Gary

2015-01-01

Children with specific language impairment (SLI) perform poorly on sentence repetition tasks across different spoken languages, but until now, this methodology has not been investigated in children who have SLI in a signed language. Users of a natural sign language encode different sentence meanings through their choice of signs and by altering…

Electrophysiological signatures of phonological and semantic maintenance in sentence repetition.

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Meltzer, Jed A; Kielar, Aneta; Panamsky, Lilia; Links, Kira A; Deschamps, Tiffany; Leigh, Rosie C

2017-08-01

Verbal short-term memory comprises resources for phonological rehearsal, which have been characterized anatomically, and for maintenance of semantic information, which are less understood. Sentence repetition tasks tap both processes interactively. To distinguish brain activity involved in phonological vs. semantic maintenance, we recorded magnetoencephalography during a sentence repetition task, incorporating three manipulations emphasizing one mechanism over the other. Participants heard sentences or word lists and attempted to repeat them verbatim after a 5-second delay. After MEG, participants completed a cued recall task testing how much they remembered of each sentence. Greater semantic engagement relative to phonological rehearsal was hypothesized for 1) sentences vs. word lists, 2) concrete vs. abstract sentences, and 3) well recalled vs. poorly recalled sentences. During auditory perception and the memory delay period, we found highly left-lateralized activation in the form of 8-30 Hz event-related desynchronization. Compared to abstract sentences, concrete sentences recruited posterior temporal cortex bilaterally, demonstrating a neural signature for the engagement of visual imagery in sentence maintenance. Maintenance of arbitrary word lists recruited right hemisphere dorsal regions, reflecting increased demands on phonological rehearsal. Sentences that were ultimately poorly recalled in the post-test also elicited extra right hemisphere activation when they were held in short-term memory, suggesting increased demands on phonological resources. Frontal midline theta oscillations also reflected phonological rather than semantic demand, being increased for word lists and poorly recalled sentences. These findings highlight distinct neural resources for phonological and semantic maintenance, with phonological maintenance associated with stronger oscillatory modulations. Copyright © 2017 Elsevier Inc. All rights reserved.

Haben repetitive DNA-Sequenzen biologische Funktionen?

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John, Maliyakal E.; Knöchel, Walter

1983-05-01

By DNA reassociation kinetics it is known that the eucaryotic genome consists of non-repetitive DNA, middle-repetitive DNA and highly repetitive DNA. Whereas the majority of protein-coding genes is located on non-repetitive DNA, repetitive DNA forms a constitutive part of eucaryotic DNA and its amount in most cases equals or even substantially exceeds that of non-repetitive DNA. During the past years a large body of data on repetitive DNA has accumulated and these have prompted speculations ranging from specific roles in the regulation of gene expression to that of a selfish entity with inconsequential functions. The following article summarizes recent findings on structural, transcriptional and evolutionary aspects and, although by no means being proven, some possible biological functions are discussed.

A Prime Example of the Maluma/Takete Effect? Testing for Sound Symbolic Priming.

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Sidhu, David M; Pexman, Penny M

2017-09-01

Certain nonwords, like maluma and takete, are associated with roundness and sharpness, respectively. However, this has typically been demonstrated using explicit tasks. We investigated whether this association would be detectable using a more implicit measure-a sequential priming task. We began with a replication of the standard Maluma/Takete effect (Experiments 1a and 1b) before examining whether round and sharp nonword primes facilitated the categorization of congruent shapes (Experiment 2). We found modest evidence of a priming effect in response accuracy. We next examined whether nonword primes affected categorization of ambiguous shapes, using visual (Experiment 3) and auditory primes (Experiment 4). We found that ambiguous shapes were categorized as round (sharp) more often following the presentation of a round (sharp) nonword. This suggests that phonemes may activate related shape information which then affects the processing of shapes, and that this association emerges even when participants are not explicitly searching for it. Copyright © 2016 Cognitive Science Society, Inc.

The influence of task variation on manifestation of fatigue is ambiguous : a literature review

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Luger, T.; Bosch, T.; Veeger, D.; Looze, M. de

2014-01-01

Task variation has been proposed to reduce shoulder fatigue resulting from repetitive hand-arm tasks. This review analyses the effect of task variation, both 'temporal (i.e. change of work-rest ratio)' and 'activity (i.e. job rotation)' variation, on physiological responses, endurance time (ET) and

Elementary students' engagement in failure-prone engineering design tasks

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Andrews, Chelsea Joy

Although engineering education has been practiced at the undergraduate level for over a century, only fairly recently has the field broadened to include the elementary level; the pre-college division of the American Society of Engineering Education was established in 2003. As a result, while recent education standards require engineering in elementary schools, current studies are still filling in basic research on how best to design and implement elementary engineering activities. One area in need of investigation is how students engage with physical failure in design tasks. In this dissertation, I explore how upper elementary students engage in failure-prone engineering design tasks in an out-of-school environment. In a series of three empirical case studies, I look closely at how students evaluate failed tests and decide on changes to their design constructions, how their reasoning evolves as they repeatedly encounter physical failure, and how students and facilitators co-construct testing norms where repetitive failure is manageable. I also briefly investigate how students' engagement differs in a task that features near-immediate success. By closely examining student groups' discourse and their interactions with their design constructions, I found that these students: are able to engage in iteration and see failure-as-feedback with minimal externally-imposed structure; seem to be designing in a more sophisticated manner, attending to multiple causal factors, after experiencing repetitive failure; and are able to manage the stress and frustration of repetitive failure, provided the co-constructed testing norms of the workshop environment are supportive of failure management. These results have both pedagogical implications, in terms of how to create and facilitate design tasks, and methodological implications--namely, I highlight the particular insights afforded by a case study approach for analyzing engagement in design tasks.

Contributions of Phonological Processing Skills to Reading Skills in Arabic Speaking Children

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Taibah, Nadia J.; Haynes, Charles W.

2011-01-01

This cross-sectional study investigated contributions of phonological awareness (Elision and blending), rapid naming (object, color, letter, and digit), and phonological memory (nonword repetition and Digit Span) to basic decoding and fluency skills in Arabic. Participants were 237 Arabic speaking children from Grades K-3. Dependent measures…

Reduced Performance During a Sentence Repetition Task by Continuous Theta-Burst Magnetic Stimulation of the Pre-supplementary Motor Area

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Dietrich, Susanne; Hertrich, Ingo; Müller-Dahlhaus, Florian; Ackermann, Hermann; Belardinelli, Paolo; Desideri, Debora; Seibold, Verena C.; Ziemann, Ulf

2018-01-01

The pre-supplementary motor area (pre-SMA) is engaged in speech comprehension under difficult circumstances such as poor acoustic signal quality or time-critical conditions. Previous studies found that left pre-SMA is activated when subjects listen to accelerated speech. Here, the functional role of pre-SMA was tested for accelerated speech comprehension by inducing a transient “virtual lesion” using continuous theta-burst stimulation (cTBS). Participants were tested (1) prior to (pre-baseline), (2) 10 min after (test condition for the cTBS effect), and (3) 60 min after stimulation (post-baseline) using a sentence repetition task (formant-synthesized at rates of 8, 10, 12, 14, and 16 syllables/s). Speech comprehension was quantified by the percentage of correctly reproduced speech material. For high speech rates, subjects showed decreased performance after cTBS of pre-SMA. Regarding the error pattern, the number of incorrect words without any semantic or phonological similarity to the target context increased, while related words decreased. Thus, the transient impairment of pre-SMA seems to affect its inhibitory function that normally eliminates erroneous speech material prior to speaking or, in case of perception, prior to encoding into a semantically/pragmatically meaningful message. PMID:29896086

Reduced Performance During a Sentence Repetition Task by Continuous Theta-Burst Magnetic Stimulation of the Pre-supplementary Motor Area

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Susanne Dietrich

2018-05-01

Full Text Available The pre-supplementary motor area (pre-SMA is engaged in speech comprehension under difficult circumstances such as poor acoustic signal quality or time-critical conditions. Previous studies found that left pre-SMA is activated when subjects listen to accelerated speech. Here, the functional role of pre-SMA was tested for accelerated speech comprehension by inducing a transient “virtual lesion” using continuous theta-burst stimulation (cTBS. Participants were tested (1 prior to (pre-baseline, (2 10 min after (test condition for the cTBS effect, and (3 60 min after stimulation (post-baseline using a sentence repetition task (formant-synthesized at rates of 8, 10, 12, 14, and 16 syllables/s. Speech comprehension was quantified by the percentage of correctly reproduced speech material. For high speech rates, subjects showed decreased performance after cTBS of pre-SMA. Regarding the error pattern, the number of incorrect words without any semantic or phonological similarity to the target context increased, while related words decreased. Thus, the transient impairment of pre-SMA seems to affect its inhibitory function that normally eliminates erroneous speech material prior to speaking or, in case of perception, prior to encoding into a semantically/pragmatically meaningful message.

Methods for Identifying Specific Language Impairment in Bilingual Populations in Germany

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Cornelia Hamann

2017-10-01

Full Text Available This study investigates the performance of 22 monolingual and 54 bilingual children with and without specific language impairment (SLI, in a non-word repetition task (NWRT and a sentence repetition task (SRT. Both tasks were constructed according to the principles for LITMUS tools (Language Impairment Testing in Multilingual Settings developed within COST Action IS0804 and incorporated phonological or syntactic structures that are linguistically complex and have been shown to be difficult for children with SLI across languages. For phonology these are in particular (nonwords containing consonant clusters. In morphosyntax, complexity has been attributed to factors such as embedding and/or syntactic movement. Tasks focusing on such structures are expected to identify SLI in bilinguals across language combinations. This is notoriously difficult because structures that are problematic for typically developing bilinguals (BiTDs and monolingual children with SLI (MoSLI often overlap. We show that the NWRT and the SRT are reliable tools for identification of SLI in bilingual contexts. However, interpretation of the performance of bilingual children depends on background information as provided by parental questionnaires. To evaluate the accuracy of our tasks, we recruited children in ordinary kindergartens or schools and in speech language therapy centers and verified their status with a battery of standardized language tests, assessing bilingual children in both their languages. We consider a bilingual child language impaired if she shows impairments in two language domains in both her languages. For assessment, we used tests normed for monolinguals (with one exception and adjusted the norms for bilingualism and for language dominance. This procedure established the following groups: 10 typical monolinguals (MoTD, 12 MoSLI, 46 BiTD, and 8 bilingual children with SLI (BiSLI. Our results show that both tasks target relevant structures: monolingual

"N"-2 Repetition Costs Depend on Preparation in Trials "n"-1 and "n"-2

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Scheil, Juliane; Kleinsorge, Thomas

2014-01-01

In task switching, a common result supporting the notion of inhibitory processes as a determinant of switch costs is the occurrence of "n"-2 repetition costs. Evidence suggests that this effect is not affected by preparation. However, the role of preparation on preceding trials has been neglected so far. In this study, evidence for an…

Repetition and lag effects in movement recognition.

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Hall, C R; Buckolz, E

1982-03-01

Whether repetition and lag improve the recognition of movement patterns was investigated. Recognition memory was tested for one repetition, two-repetitions massed, and two-repetitions distributed with movement patterns at lags of 3, 5, 7, and 13. Recognition performance was examined both immediately afterwards and following a 48 hour delay. Both repetition and lag effects failed to be demonstrated, providing some support for the claim that memory is unaffected by repetition at a constant level of processing (Craik & Lockhart, 1972). There was, as expected, a significant decrease in recognition memory following the retention interval, but this appeared unrelated to repetition or lag.

Prediction of the Maximum Number of Repetitions and Repetitions in Reserve From Barbell Velocity.

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García-Ramos, Amador; Torrejón, Alejandro; Feriche, Belén; Morales-Artacho, Antonio J; Pérez-Castilla, Alejandro; Padial, Paulino; Haff, Guy Gregory

2018-03-01

To provide 2 general equations to estimate the maximum possible number of repetitions (XRM) from the mean velocity (MV) of the barbell and the MV associated with a given number of repetitions in reserve, as well as to determine the between-sessions reliability of the MV associated with each XRM. After determination of the bench-press 1-repetition maximum (1RM; 1.15 ± 0.21 kg/kg body mass), 21 men (age 23.0 ± 2.7 y, body mass 72.7 ± 8.3 kg, body height 1.77 ± 0.07 m) completed 4 sets of as many repetitions as possible against relative loads of 60%1RM, 70%1RM, 80%1RM, and 90%1RM over 2 separate sessions. The different loads were tested in a randomized order with 10 min of rest between them. All repetitions were performed at the maximum intended velocity. Both the general equation to predict the XRM from the fastest MV of the set (CV = 15.8-18.5%) and the general equation to predict MV associated with a given number of repetitions in reserve (CV = 14.6-28.8%) failed to provide data with acceptable between-subjects variability. However, a strong relationship (median r 2  = .984) and acceptable reliability (CV  .85) were observed between the fastest MV of the set and the XRM when considering individual data. These results indicate that generalized group equations are not acceptable methods for estimating the XRM-MV relationship or the number of repetitions in reserve. When attempting to estimate the XRM-MV relationship, one must use individualized relationships to objectively estimate the exact number of repetitions that can be performed in a training set.

[Attempt for development of rapid word reading test for children--evaluation of reliability and validity].

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Hashimoto, Ryusaku; Kashiwagi, Mitsuru; Suzuki, Shuhei

2008-09-01

We developed a rapid word reading test for examining the phonological processing ability of Japanese children. We prepared two versions of the test, version A and B. Each test has word and non-word tasks. Twenty-two healthy boys of third grade in primary schools participated in this validation study. For criterion related validity, we performed the serial Hiragana reading test, the sentence reading test, Raven's coloured progressive matrices (RCPM), the Token test for children, the Kana word dictation test, the standardized comprehension test of abstract words (SCTAW), and Trail Circle test. The reading times of the newly developed test correlated moderately or highly with those of the serial Hiragana reading test and the sentence reading test. However, the scores of the other tests (RCPM, Token test for children, Kana word dictation test, SCTAW, Trail Circle test) did not correlated with the reading time of the rapid word reading test. Test-retest reliabilities in the word tasks were more than moderate: 0.52 and 0.76 in versions A and B, while those in the non-word tasks were high: 0.91 and 0.88 in versions A and B. The correlation coefficient between versions A and B was 0.7 for the word tasks and 0.92 for the non-word tasks. This study showed that the rapid word reading test has substantial validity and reliability for testing the phonological processing ability of Japanese children. In addition, the non-word tasks were more suitable for selectively examining the speed of the grapheme to phoneme conversion process.

MODULATION OF EVENT-RELATED POTENTIALS BY WORD REPETITION - THE ROLE OF VISUAL SELECTIVE ATTENTION

NARCIS (Netherlands)

OTTEN, LJ; RUGG, MD; DOYLE, MC

1993-01-01

Event-related potentials (ERPs) were recorded while subjects viewed visually presented words, some of which occurred twice. Each trial consisted of two colored letter strings, the requirement being to attend to and make a word/nonword discrimination for one of the strings. Attention was manipulated

If you negate, you may forget: negated repetitions impair memory compared with affirmative repetitions.

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Mayo, Ruth; Schul, Yaacov; Rosenthal, Meytal

2014-08-01

One of the most robust laws of memory is that repeated activation improves memory. Our study shows that the nature of repetition matters. Specifically, although both negated repetition and affirmative repetition improve memory compared with no repetition, negated repetition hinders memory compared with affirmative repetition. After showing participants different entities, we asked them about features of these entities, leading to either "yes" or "no" responses. Our findings show that correctly negating an incorrect feature of an entity elicits an active forgetting effect compared with correctly affirming its true features. For example, after seeing someone drink a glass of white wine, answering "no" to "was it red wine?" may lead one to greater memory loss of the individual drinking wine at all compared with answering "yes" to "was it white wine?" We find this negation-induced forgetting effect in 4 experiments that differ in (a) the meaning given for the negation, (b) the type of stimuli (visual or verbal), and (c) the memory measure (recognition or free recall). We discuss possible underlying mechanisms and offer theoretical and applied implications of the negation-induced forgetting effect in relation to other known inhibition effects. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Audiovisual sentence repetition as a clinical criterion for auditory development in Persian-language children with hearing loss.

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Oryadi-Zanjani, Mohammad Majid; Vahab, Maryam; Rahimi, Zahra; Mayahi, Anis

2017-02-01

It is important for clinician such as speech-language pathologists and audiologists to develop more efficient procedures to assess the development of auditory, speech and language skills in children using hearing aid and/or cochlear implant compared to their peers with normal hearing. So, the aim of study was the comparison of the performance of 5-to-7-year-old Persian-language children with and without hearing loss in visual-only, auditory-only, and audiovisual presentation of sentence repetition task. The research was administered as a cross-sectional study. The sample size was 92 Persian 5-7 year old children including: 60 with normal hearing and 32 with hearing loss. The children with hearing loss were recruited from Soroush rehabilitation center for Persian-language children with hearing loss in Shiraz, Iran, through consecutive sampling method. All the children had unilateral cochlear implant or bilateral hearing aid. The assessment tool was the Sentence Repetition Test. The study included three computer-based experiments including visual-only, auditory-only, and audiovisual. The scores were compared within and among the three groups through statistical tests in α = 0.05. The score of sentence repetition task between V-only, A-only, and AV presentation was significantly different in the three groups; in other words, the highest to lowest scores belonged respectively to audiovisual, auditory-only, and visual-only format in the children with normal hearing (P audiovisual sentence repetition scores in all the 5-to-7-year-old children (r = 0.179, n = 92, P = 0.088), but audiovisual sentence repetition scores were found to be strongly correlated with auditory-only scores in all the 5-to-7-year-old children (r = 0.943, n = 92, P = 0.000). According to the study's findings, audiovisual integration occurs in the 5-to-7-year-old Persian children using hearing aid or cochlear implant during sentence repetition similar to their peers with normal hearing

Effects of Repetitive Shoulder Activity on the Subacromial Space in Manual Wheelchair Users

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Yen-Sheng Lin

2014-01-01

Full Text Available This study investigated (1 the effect of repetitive weight-relief raises (WR and shoulder external rotation (ER on the acromiohumeral distance (AHD among manual wheelchair users (MWUs and (2 the relationship between shoulder pain, subject characteristics, and AHD changes. Twenty-three MWUs underwent ultrasound imaging of the nondominant shoulder in an unloaded baseline position and while holding a WR position before and after the WR/ER tasks. Paired t-tests and Spearman correlational analysis were used to assess differences in the AHD before and after each task and the relationships between pain, subject characteristics, and the AHD measures. A significant reduction in the subacromial space (P<0.01 occurred when subjects performed a WR position compared to baseline. Individuals with increased years of disability had greater AHD percentage narrowing after WR (P=0.008. Increased shoulder pain was associated with AHD percentage narrowing after ER (P≤0.007. The results support clinical practice guidelines that recommend MWUs limit WR to preserve shoulder function. The isolated repetitive shoulder activity did not contribute to the changes of subacromial space in MWUs. The ultrasonographic measurement of the AHD may be a target for identifying future interventions that prevent pain.

Learning Correct Responses and Errors in the Hebb Repetition Effect: Two Faces of the Same Coin

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Couture, Mathieu; Lafond, Daniel; Tremblay, Sebastien

2008-01-01

In a serial recall task, the "Hebb repetition effect" occurs when recall performance improves for a sequence repeated throughout the experimental session. This phenomenon has been replicated many times. Nevertheless, such cumulative learning seldom leads to perfect recall of the whole sequence, and errors persist. Here the authors report…

Selective activation of the superior frontal gyrus in task-switching: an event-related fNIRS study.

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Cutini, Simone; Scatturin, Pietro; Menon, Enrica; Bisiacchi, Patrizia Silvia; Gamberini, Luciano; Zorzi, Marco; Dell'Acqua, Roberto

2008-08-15

In the task-switching paradigm, reaction time is longer and accuracy is worse in switch trials relative to repetition trials. This so-called switch cost has been ascribed to the engagement of control processes required to alternate between distinct stimulus-response mapping rules. Neuroimaging studies have reported an enhanced activation of the human lateral prefrontal cortex and the superior frontal gyrus during the task-switching paradigm. Whether neural activation in these regions is dissociable and associated with separable cognitive components of task switching has been a matter of recent debate. We used multi-channel near-infrared spectroscopy (fNIRS) to measure brain cortical activity in a task-switching paradigm designed to avoid task differences, order predictability, and frequency effects. The results showed a generalized bilateral activation of the lateral prefrontal cortex and the superior frontal gyrus in both switch trials and repetition trials. To isolate the activity selectively associated with the task-switch, the overall activity recorded during repetition trials was subtracted from the activity recorded during switch trials. Following subtraction, the remaining activity was entirely confined to the left portion of the superior frontal gyrus. The present results suggest that factors associated with load and maintenance of distinct stimulus-response mapping rules in working memory are likely contributors to the activation of the lateral prefrontal cortex, whereas only activity in the left superior frontal gyrus can be linked unequivocally to switching between distinct cognitive tasks.

Improved discrimination of visual stimuli following repetitive transcranial magnetic stimulation.

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Michael L Waterston

Full Text Available BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS at certain frequencies increases thresholds for motor-evoked potentials and phosphenes following stimulation of cortex. Consequently rTMS is often assumed to introduce a "virtual lesion" in stimulated brain regions, with correspondingly diminished behavioral performance. METHODOLOGY/PRINCIPAL FINDINGS: Here we investigated the effects of rTMS to visual cortex on subjects' ability to perform visual psychophysical tasks. Contrary to expectations of a visual deficit, we find that rTMS often improves the discrimination of visual features. For coarse orientation tasks, discrimination of a static stimulus improved consistently following theta-burst stimulation of the occipital lobe. Using a reaction-time task, we found that these improvements occurred throughout the visual field and lasted beyond one hour post-rTMS. Low-frequency (1 Hz stimulation yielded similar improvements. In contrast, we did not find consistent effects of rTMS on performance in a fine orientation discrimination task. CONCLUSIONS/SIGNIFICANCE: Overall our results suggest that rTMS generally improves or has no effect on visual acuity, with the nature of the effect depending on the type of stimulation and the task. We interpret our results in the context of an ideal-observer model of visual perception.

Repetitive Questioning Exasperates Caregivers

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R. C. Hamdy MD

2018-01-01

Full Text Available Repetitive questioning is due to an impaired episodic memory and is a frequent, often presenting, problem in patients with Alzheimer’s disease (amnestic type. It is due to the patients’ difficulties learning new information, retaining it, and recalling it, and is often aggravated by a poor attention span and easy distractibility. A number of factors may trigger and maintain repetitive questioning. Caregivers should try to identify and address these triggers. In the case discussion presented, it is due to the patient’s concerns about her and her family’s safety triggered by watching a particularly violent movie aired on TV. What went wrong in the patient/caregiver interaction and how it could have been avoided or averted are explored. Also reviewed are the impact of repetitive questioning, the challenges it raises for caregivers, and some effective intervention strategies that may be useful to diffuse the angst that caregivers experience with repetitive questioning.

SYNCHRONOUS CMC, WORKING MEMORY, AND L2 ORAL PROFICIENCY DEVELOPMENT

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J. Scott Payne

2005-09-01

Full Text Available Recently a number of quasi-experimental studies have investigated the potential of a cross-modality transfer of second language competency between real-time, conversational exchange via text and speech (Abrams, 2003; Beauvious, 1998; Kost, 2004; Payne & Whitney, 2002. Payne and Whitney employed Levelt's (1989 model of language production and concepts from working memory as a rationale for a hypothesized connection between synchronous computer-mediated communication (SCMC and second language (L2 speech and as a basis for predicting the differential contributions of SCMC to the L2 oral proficiency development.This study extends the psycholinguistic framework reported in Payne and Whitney (2002 with discourse and corpus analytic techniques to explore how individual differences in working memory capacity may affect the frequency of repetition and other patterns of language use in chatroom discourse. Working memory capacity was measured by a reading span and nonword repetition test. Oral proficiency was measured with a speaking task that solicited a 5-minute speech sample and was scored based on a holistic scale. The data collected from 20 chat sessions were analyzed for occurrences of repetition and relexicalization, as well as language output measures. Findings suggest a connection between working memory and language output as measured in this study.

RS-20 type repetitive generator with planar configuration of plasma opening switch

Energy Technology Data Exchange (ETDEWEB)

Agalakov, V P; Barinov, N U; Belenki, G S [Kurchatov Inst., Moscow (Russian Federation); and others

1997-12-31

The existing experience with the production of repetitive rate accelerators with a high peak power (in excess of 10{sup 10} W) and an average power above 50 kW makes it possible to resolve a number of physics and technology tasks which are connected with the reliability and life of the accelerator. The design and results on optimization of a simple plasma opening switch (POS) are discussed. The final design of the POS provided voltages of up to 2 MV and had a life of more than 105 pulses including 4 hours of continuous operation under 4 Hz repetition rate and wall plug power 65 kW. This unit was tested at the RS-20 type accelerator both at the Kurchatov Institute and at the Northwest Institute of Nuclear Technology in China. (author). 5 figs., 1 ref.

Computer Simulations of Developmental Change: The Contributions of Working Memory Capacity and Long-Term Knowledge

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Jones, Gary; Gobet, Fernand; Pine, Julian M.

2008-01-01

Increasing working memory (WM) capacity is often cited as a major influence on children's development and yet WM capacity is difficult to examine independently of long-term knowledge. A computational model of children's nonword repetition (NWR) performance is presented that independently manipulates long-term knowledge and WM capacity to determine…

Phonological Networks and New Word Learning

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Service, Elisabet

2006-01-01

The first report of a connection between vocabulary learning and phonological short-term memory was published in 1988 (Baddeley, Papagno, & Vallar, 1988). At that time, both Susan Gathercole and I were involved in longitudinal studies, investigating the relation between nonword repetition and language learning. We both found a connection. Now,…

Orthography and Modality Influence Speech Production in Adults and Children.

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Saletta, Meredith; Goffman, Lisa; Hogan, Tiffany P

2016-12-01

The acquisition of literacy skills influences the perception and production of spoken language. We examined if orthography influences implicit processing in speech production in child readers and in adult readers with low and high reading proficiency. Children (n = 17), adults with typical reading skills (n = 17), and adults demonstrating low reading proficiency (n = 18) repeated or read aloud nonwords varying in orthographic transparency. Analyses of implicit linguistic processing (segmental accuracy and speech movement stability) were conducted. The accuracy and articulatory stability of productions of the nonwords were assessed before and after repetition or reading. Segmental accuracy results indicate that all 3 groups demonstrated greater learning when they were able to read, rather than just hear, the nonwords. Speech movement results indicate that, for adults with poor reading skills, exposure to the nonwords in a transparent spelling reduces the articulatory variability of speech production. Reading skill was correlated with speech movement stability in the groups of adults. In children and adults, orthography interacts with speech production; all participants integrate orthography into their lexical representations. Adults with poor reading skills do not use the same reading or speaking strategies as children with typical reading skills.

Exact and conceptual repetition dissociate conceptual memory tests: problems for transfer appropriate processing theory.

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McDermott, K B; Roediger, H L

1996-03-01

Three experiments examined whether a conceptual implicit memory test (specifically, category instance generation) would exhibit repetition effects similar to those found in free recall. The transfer appropriate processing account of dissociations among memory tests led us to predict that the tests would show parallel effects; this prediction was based upon the theory's assumption that conceptual tests will behave similarly as a function of various independent variables. In Experiment 1, conceptual repetition (i.e., following a target word [e.g., puzzles] with an associate [e.g., jigsaw]) did not enhance priming on the instance generation test relative to the condition of simply presenting the target word once, although this manipulation did affect free recall. In Experiment 2, conceptual repetition was achieved by following a picture with its corresponding word (or vice versa). In this case, there was an effect of conceptual repetition on free recall but no reliable effect on category instance generation or category cued recall. In addition, we obtained a picture superiority effect in free recall but not in category instance generation. In the third experiment, when the same study sequence was used as in Experiment 1, but with instructions that encouraged relational processing, priming on the category instance generation task was enhanced by conceptual repetition. Results demonstrate that conceptual memory tests can be dissociated and present problems for Roediger's (1990) transfer appropriate processing account of dissociations between explicit and implicit tests.

Neural substrates of sublexical processing for spelling.

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DeMarco, Andrew T; Wilson, Stephen M; Rising, Kindle; Rapcsak, Steven Z; Beeson, Pélagie M

2017-01-01

We used fMRI to examine the neural substrates of sublexical phoneme-grapheme conversion during spelling in a group of healthy young adults. Participants performed a writing-to-dictation task involving irregular words (e.g., choir), plausible nonwords (e.g., kroid), and a control task of drawing familiar geometric shapes (e.g., squares). Written production of both irregular words and nonwords engaged a left-hemisphere perisylvian network associated with reading/spelling and phonological processing skills. Effects of lexicality, manifested by increased activation during nonword relative to irregular word spelling, were noted in anterior perisylvian regions (posterior inferior frontal gyrus/operculum/precentral gyrus/insula), and in left ventral occipito-temporal cortex. In addition to enhanced neural responses within domain-specific components of the language network, the increased cognitive demands associated with spelling nonwords engaged domain-general frontoparietal cortical networks involved in selective attention and executive control. These results elucidate the neural substrates of sublexical processing during written language production and complement lesion-deficit correlation studies of phonological agraphia. Copyright © 2016 Elsevier Inc. All rights reserved.

Computer-Related Repetitive Stress Injuries

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... Staying Safe Videos for Educators Search English Español Computer-Related Repetitive Stress Injuries KidsHealth / For Parents / Computer-Related Repetitive Stress Injuries What's in this article? ...

Changed activation, oxygenation, and pain response of chronically painful muscles to repetitive work after training interventions: a randomized controlled trial

DEFF Research Database (Denmark)

Søgaard, Karen; Blangsted, Anne Katrine; Nielsen, Pernille Kofoed

2012-01-01

The aim of this randomized controlled trial was to assess changes in myalgic trapezius activation, muscle oxygenation, and pain intensity during repetitive and stressful work tasks in response to 10 weeks of training. In total, 39 women with a clinical diagnosis of trapezius myalgia were randomly...... levels of pain. SST lowered the relative EMG amplitude by 36%, and decreased pain during resting and working conditions by 52 and 38%, respectively, without affecting trapezius oxygenation. In conclusion, GFT performed as leg-bicycling decreased pain development during repetitive work tasks, possibly due...... assigned to: (1) general fitness training performed as leg-bicycling (GFT); (2) specific strength training of the neck/shoulder muscles (SST) or (3) reference intervention without physical exercise. Electromyographic activity (EMG), tissue oxygenation (near infrared spectroscopy), and pain intensity were...

Personalized Video Feedback and Repeated Task Practice Improve Laparoscopic Knot-Tying Skills: Two Controlled Trials.

Science.gov (United States)

Abbott, Eduardo F; Thompson, Whitney; Pandian, T K; Zendejas, Benjamin; Farley, David R; Cook, David A

2017-11-01

Compare the effect of personalized feedback (PF) vs. task demonstration (TD), both delivered via video, on laparoscopic knot-tying skills and perceived workload; and evaluate the effect of repeated practice. General surgery interns and research fellows completed four repetitions of a simulated laparoscopic knot-tying task at one-month intervals. Midway between repetitions, participants received via e-mail either a TD video (demonstration by an expert) or a PF video (video of their own performance with voiceover from a blinded senior surgeon). Each participant received at least one video per format, with sequence randomly assigned. Outcomes included performance scores and NASA Task Load Index (NASA-TLX) scores. To evaluate the effectiveness of repeated practice, scores from these trainees on a separate delayed retention test were compared against historical controls who did not have scheduled repetitions. Twenty-one trainees completed the randomized study. Mean change in performance scores was significantly greater for those receiving PF (difference = 23.1 of 150 [95% confidence interval (CI): 0, 46.2], P = .05). Perceived workload was also significantly reduced (difference = -3.0 of 20 [95% CI: -5.8, -0.3], P = .04). Compared with historical controls (N = 93), the 21 with scheduled repeated practice had higher scores on the laparoscopic knot-tying assessment two weeks after the final repetition (difference = 1.5 of 10 [95% CI: 0.2, 2.8], P = .02). Personalized video feedback improves trainees' procedural performance and perceived workload compared with a task demonstration video. Brief monthly practice sessions support skill acquisition and retention.

Monkeys Rely on Recency of Stimulus Repetition When Solving Short-Term Memory Tasks

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Wittig, John H., Jr.; Richmond, Barry J.

2014-01-01

Seven monkeys performed variants of two short-term memory tasks that others have used to differentiate between selective and nonselective memory mechanisms. The first task was to view a list of sequentially presented images and identify whether a test matched any image from the list, but not a distractor from a preceding list. Performance was best…

The Effect of Haptic Guidance on Learning a Hybrid Rhythmic-Discrete Motor Task.

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Marchal-Crespo, Laura; Bannwart, Mathias; Riener, Robert; Vallery, Heike

2015-01-01

Bouncing a ball with a racket is a hybrid rhythmic-discrete motor task, combining continuous rhythmic racket movements with discrete impact events. Rhythmicity is exceptionally important in motor learning, because it underlies fundamental movements such as walking. Studies suggested that rhythmic and discrete movements are governed by different control mechanisms at different levels of the Central Nervous System. The aim of this study is to evaluate the effect of fixed/fading haptic guidance on learning to bounce a ball to a desired apex in virtual reality with varying gravity. Changing gravity changes dominance of rhythmic versus discrete control: The higher the value of gravity, the more rhythmic the task; lower values reduce the bouncing frequency and increase dwell times, eventually leading to a repetitive discrete task that requires initiation and termination, resembling target-oriented reaching. Although motor learning in the ball-bouncing task with varying gravity has been studied, the effect of haptic guidance on learning such a hybrid rhythmic-discrete motor task has not been addressed. We performed an experiment with thirty healthy subjects and found that the most effective training condition depended on the degree of rhythmicity: Haptic guidance seems to hamper learning of continuous rhythmic tasks, but it seems to promote learning for repetitive tasks that resemble discrete movements.

Muscle oxygenation and glycolysis in females with trapezius myalgia during stress and repetitive work using microdialysis and NIRS

DEFF Research Database (Denmark)

Sjøgaard, Gisela; Rosendal, Lars; Kristiansen, Jesper

2010-01-01

The aim of this investigation was to study female workers active in the labour market for differences between those with trapezius myalgia (MYA) and without (CON) during repetitive pegboard (PEG) and stress (STR) tasks regarding (1) relative muscle load, (2) trapezius muscle blood flow, (3...

Repetition Enhancement of Amygdala and Visual Cortex Functional Connectivity Reflects Nonconscious Memory for Negative Visual Stimuli.

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Kark, Sarah M; Slotnick, Scott D; Kensinger, Elizabeth A

2016-12-01

Most studies using a recognition memory paradigm examine the neural processes that support the ability to consciously recognize past events. However, there can also be nonconscious influences from the prior study episode that reflect repetition suppression effects-a reduction in the magnitude of activity for repeated presentations of stimuli-that are revealed by comparing neural activity associated with forgotten items to correctly rejected novel items. The present fMRI study examined the effect of emotional valence (positive vs. negative) on repetition suppression effects. Using a standard recognition memory task, 24 participants viewed line drawings of previously studied negative, positive, and neutral photos intermixed with novel line drawings. For each item, participants made an old-new recognition judgment and a sure-unsure confidence rating. Collapsed across valence, repetition suppression effects were found in ventral occipital-temporal cortex and frontal regions. Activity levels in the majority of these regions were not modulated by valence. However, repetition enhancement of the amygdala and ventral occipital-temporal cortex functional connectivity reflected nonconscious memory for negative items. In this study, valence had little effect on activation patterns but had a larger effect on functional connectivity patterns that were markers of nonconscious memory. Beyond memory and emotion, these findings are relevant to other cognitive and social neuroscientists that utilize fMRI repetition effects to investigate perception, attention, social cognition, and other forms of learning and memory.

Muscle oxygenation and glycolysis in females with trapezius myalgia during stress and repetitive work using microdialysis and NIRS

DEFF Research Database (Denmark)

Sjøgaard, Gisela; Rosendal, Lars; Kristiansen, Jesper

2010-01-01

The aim of this investigation was to study female workers active in the labour market for differences between those with trapezius myalgia (MYA) and without (CON) during repetitive pegboard (PEG) and stress (STR) tasks regarding (1) relative muscle load, (2) trapezius muscle blood flow, (3) metab...

Design and control of RUPERT: a device for robotic upper extremity repetitive therapy.

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Sugar, Thomas G; He, Jiping; Koeneman, Edward J; Koeneman, James B; Herman, Richard; Huang, H; Schultz, Robert S; Herring, D E; Wanberg, J; Balasubramanian, Sivakumar; Swenson, Pete; Ward, Jeffrey A

2007-09-01

The structural design, control system, and integrated biofeedback for a wearable exoskeletal robot for upper extremity stroke rehabilitation are presented. Assisted with clinical evaluation, designers, engineers, and scientists have built a device for robotic assisted upper extremity repetitive therapy (RUPERT). Intense, repetitive physical rehabilitation has been shown to be beneficial overcoming upper extremity deficits, but the therapy is labor intensive and expensive and difficult to evaluate quantitatively and objectively. The RUPERT is developed to provide a low cost, safe and easy-to-use, robotic-device to assist the patient and therapist to achieve more systematic therapy at home or in the clinic. The RUPERT has four actuated degrees-of-freedom driven by compliant and safe pneumatic muscles (PMs) on the shoulder, elbow, and wrist. They are programmed to actuate the device to extend the arm and move the arm in 3-D space. It is very important to note that gravity is not compensated and the daily tasks are practiced in a natural setting. Because the device is wearable and lightweight to increase portability, it can be worn standing or sitting providing therapy tasks that better mimic activities of daily living. The sensors feed back position and force information for quantitative evaluation of task performance. The device can also provide real-time, objective assessment of functional improvement. We have tested the device on stroke survivors performing two critical activities of daily living (ADL): reaching out and self feeding. The future improvement of the device involves increased degrees-of-freedom and interactive control to adapt to a user's physical conditions.

Responses of algesic and metabolic substances to 8h of repetitive manual work in myalgic human trapezius muscle

DEFF Research Database (Denmark)

Larsson, B.; Rosendal, L.; Kristiansen, J.

2008-01-01

The trapezius muscle often develops pain as the result of repetitive and stressful work tasks although it is unclear to what extent this pain is due to alterations in muscle concentrations of algesic/nociceptive substances. Twenty women with chronic neck- and shoulder pain (TM) whose work required...... highly repetitive work tasks and 20 pain-free female colleagues (CON) were studied during and after a full 8-hour workday. We collected microdialysates from their dominant/most painful trapezius muscle; concentrations of serotonin, glutamate, lactate, pyruvate, potassium, bradykinin, and cytokines...... muscles. TM had higher concentrations of glutamate (71+/-42 vs. 36+/-15mumoll(-1)) and pyruvate (187+/-89 vs. 125+/-63mumoll(-1)) than CON. Interstitial serotonin was higher in TM (before work: 10.6+/-10.8 vs. 2.2+/-1.2nM; after work: 9.2+/-8.3 vs. 1.5+/-2.9nM). The trapezius blood flow during the working...

Linking Working Memory and Long-Term Memory: A Computational Model of the Learning of New Words

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Jones, Gary; Gobet, Fernand; Pine, Julian M.

2007-01-01

The nonword repetition (NWR) test has been shown to be a good predictor of children's vocabulary size. NWR performance has been explained using phonological working memory, which is seen as a critical component in the learning of new words. However, no detailed specification of the link between phonological working memory and long-term memory…

Patterns of cerebral activation during lexical and phonological reading in Portuguese

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Senaha M.L.H.

2005-01-01

Full Text Available According to the concepts of cognitive neuropsychology, there are two principal routes of reading processing: a lexical route, in which global reading of words occurs and a phonological route, responsible for the conversion of the graphemes into their respective phonemes. In the present study, functional magnetic resonance imaging (fMRI was used to investigate the patterns of cerebral activation in lexical and phonological reading by 13 healthy women with a formal educational level greater than 11 years. Participants were submitted to a silent reading task containing three types of stimuli: real words (irregular and foreign words, nonwords and illegitimate graphic stimuli. An increased number of activated voxels were identified by fMRI in the word reading (lexical processing than in the nonword reading (phonological processing task. In word reading, activation was greater than for nonwords in the following areas: superior, middle and inferior frontal gyri, and bilateral superior temporal gyrus, right cerebellum and the left precentral gyrus, as indicated by fMRI. In the reading of nonwords, the activation was predominant in the right cerebellum and in the left superior temporal gyrus. The results of the present study suggest the existence of differences in the patterns of cerebral activation during lexical and phonological reading, with greater involvement of the right hemisphere in reading words than nonwords.

Voice and Fluency Changes as a Function of Speech Task and Deep Brain Stimulation

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Van Lancker Sidtis, Diana; Rogers, Tiffany; Godier, Violette; Tagliati, Michele; Sidtis, John J.

2010-01-01

Purpose: Speaking, which naturally occurs in different modes or "tasks" such as conversation and repetition, relies on intact basal ganglia nuclei. Recent studies suggest that voice and fluency parameters are differentially affected by speech task. In this study, the authors examine the effects of subcortical functionality on voice and fluency,…

Dual-Task Interference: The Effects of Verbal Cognitive Tasks on Upright Postural Stability in Parkinson's Disease

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J. D. Holmes

2010-01-01

Full Text Available Although dual-task interference has previously been demonstrated to have a significant effect on postural control among individuals with Parkinson's disease, the impact of speech complexity on postural control has not been demonstrated using quantitative biomechanical measures. The postural stability of twelve participants with idiopathic Parkinson's disease and twelve healthy age-matched controls was evaluated under three conditions: (1 without a secondary task, (2 performing a rote repetition task and (3 generating a monologue. Results suggested a significant effect of cognitive load on biomechanical parameters of postural stability. Although both groups increased their postural excursion, individuals with Parkinson's disease demonstrated significantly reduced excursion as compared with that of healthy age-matched controls. This suggests that participants with Parkinson's disease may be overconstraining their postural adjustments in order to focus attention on the cognitive tasks without losing their balance. Ironically, this overconstraint may place the participant at greater risk for a fall.

Repetitive Questioning II

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R. C. Hamdy MD

2018-02-01

Full Text Available Repetitive questioning is a major problem for caregivers, particularly taxing if they are unable to recognize and understand the reasons why their loved one keeps asking the same question over and over again. Caregivers may be tempted to believe that the patient does not even try to remember the answer given or is just getting obnoxious. This is incorrect. Repetitive questioning is due to the underlying disease: The patient’s short term memory is impaired and he is unable to register, encode, retain and retrieve the answer. If he is concerned about a particular topic, he will keep asking the same question over and over again. To the patient each time she asks the question, it is as if she asked it for the first time. Just answering repetitive questioning by providing repeatedly the same answer is not sufficient. Caregivers should try to identify the underlying cause for this repetitive questioning. In an earlier case study, the patient was concerned about her and her family’s safety and kept asking whether the doors are locked. In this present case study, the patient does not know how to handle the awkward situation he finds himself in. He just does not know what to do. He is not able to adjust to the new unexpected situation. So he repeatedly wants to reassure himself that he is not intruding by asking the same question over and over again. We discuss how the patient’s son-in-law could have avoided this situation and averted the catastrophic ending.

Emotional response to musical repetition.

Science.gov (United States)

Livingstone, Steven R; Palmer, Caroline; Schubert, Emery

2012-06-01

Two experiments examined the effects of repetition on listeners' emotional response to music. Listeners heard recordings of orchestral music that contained a large section repeated twice. The music had a symmetric phrase structure (same-length phrases) in Experiment 1 and an asymmetric phrase structure (different-length phrases) in Experiment 2, hypothesized to alter the predictability of sensitivity to musical repetition. Continuous measures of arousal and valence were compared across music that contained identical repetition, variation (related), or contrasting (unrelated) structure. Listeners' emotional arousal ratings differed most for contrasting music, moderately for variations, and least for repeating musical segments. A computational model for the detection of repeated musical segments was applied to the listeners' emotional responses. The model detected the locations of phrase boundaries from the emotional responses better than from performed tempo or physical intensity in both experiments. These findings indicate the importance of repetition in listeners' emotional response to music and in the perceptual segmentation of musical structure.

Task path planning, scheduling and learning for free-ranging robot systems

Science.gov (United States)

Wakefield, G. Steve

1987-01-01

The development of robotics applications for space operations is often restricted by the limited movement available to guided robots. Free ranging robots can offer greater flexibility than physically guided robots in these applications. Presented here is an object oriented approach to path planning and task scheduling for free-ranging robots that allows the dynamic determination of paths based on the current environment. The system also provides task learning for repetitive jobs. This approach provides a basis for the design of free-ranging robot systems which are adaptable to various environments and tasks.

Does Top-Down Feedback Modulate the Encoding of Orthographic Representations During Visual-Word Recognition?

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Perea, Manuel; Marcet, Ana; Vergara-Martínez, Marta

2016-09-01

In masked priming lexical decision experiments, there is a matched-case identity advantage for nonwords, but not for words (e.g., ERTAR-ERTAR words when top-down feedback is minimized. We employed a task that taps prelexical orthographic processes: the masked prime same-different task. For "same" trials, results showed faster response times for targets when preceded by a briefly presented matched-case identity prime than when preceded by a mismatched-case identity prime. Importantly, this advantage was similar in magnitude for nonwords and words. This finding constrains the interplay of bottom-up versus top-down mechanisms in models of visual-word identification.

Repetitive learning control of continuous chaotic systems

International Nuclear Information System (INIS)

Chen Maoyin; Shang Yun; Zhou Donghua

2004-01-01

Combining a shift method and the repetitive learning strategy, a repetitive learning controller is proposed to stabilize unstable periodic orbits (UPOs) within chaotic attractors in the sense of least mean square. If nonlinear parts in chaotic systems satisfy Lipschitz condition, the proposed controller can be simplified into a simple proportional repetitive learning controller

Novel porcine repetitive elements

Directory of Open Access Journals (Sweden)

Nonneman Dan J

2006-12-01

Full Text Available Abstract Background Repetitive elements comprise ~45% of mammalian genomes and are increasingly known to impact genomic function by contributing to the genomic architecture, by direct regulation of gene expression and by affecting genomic size, diversity and evolution. The ubiquity and increasingly understood importance of repetitive elements contribute to the need to identify and annotate them. We set out to identify previously uncharacterized repetitive DNA in the porcine genome. Once found, we characterized the prevalence of these repeats in other mammals. Results We discovered 27 repetitive elements in 220 BACs covering 1% of the porcine genome (Comparative Vertebrate Sequencing Initiative; CVSI. These repeats varied in length from 55 to 1059 nucleotides. To estimate copy numbers, we went to an independent source of data, the BAC-end sequences (Wellcome Trust Sanger Institute, covering approximately 15% of the porcine genome. Copy numbers in BAC-ends were less than one hundred for 6 repeat elements, between 100 and 1000 for 16 and between 1,000 and 10,000 for 5. Several of the repeat elements were found in the bovine genome and we have identified two with orthologous sites, indicating that these elements were present in their common ancestor. None of the repeat elements were found in primate, rodent or dog genomes. We were unable to identify any of the replication machinery common to active transposable elements in these newly identified repeats. Conclusion The presence of both orthologous and non-orthologous sites indicates that some sites existed prior to speciation and some were generated later. The identification of low to moderate copy number repetitive DNA that is specific to artiodactyls will be critical in the assembly of livestock genomes and studies of comparative genomics.

Document retrieval on repetitive string collections.

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Gagie, Travis; Hartikainen, Aleksi; Karhu, Kalle; Kärkkäinen, Juha; Navarro, Gonzalo; Puglisi, Simon J; Sirén, Jouni

2017-01-01

Most of the fastest-growing string collections today are repetitive, that is, most of the constituent documents are similar to many others. As these collections keep growing, a key approach to handling them is to exploit their repetitiveness, which can reduce their space usage by orders of magnitude. We study the problem of indexing repetitive string collections in order to perform efficient document retrieval operations on them. Document retrieval problems are routinely solved by search engines on large natural language collections, but the techniques are less developed on generic string collections. The case of repetitive string collections is even less understood, and there are very few existing solutions. We develop two novel ideas, interleaved LCPs and precomputed document lists , that yield highly compressed indexes solving the problem of document listing (find all the documents where a string appears), top- k document retrieval (find the k documents where a string appears most often), and document counting (count the number of documents where a string appears). We also show that a classical data structure supporting the latter query becomes highly compressible on repetitive data. Finally, we show how the tools we developed can be combined to solve ranked conjunctive and disjunctive multi-term queries under the simple [Formula: see text] model of relevance. We thoroughly evaluate the resulting techniques in various real-life repetitiveness scenarios, and recommend the best choices for each case.

REPETITIVE STRENGTH AMONG STUDENTS OF AGE 14

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Besim Halilaj

2014-06-01

Full Text Available The study involved 82 male students of the primary school “Qamil Ilazi” in Kaçanik-Kosovo.Four movement tests, which test the repetitive strength, were conducted: 1. Pull-up, 2. Sit-Up, 3. Back extension, 4. Push-up.The main goal of this study was to verify the actual motor status, respectively the component of the repetitive strength among students of age 14 of masculine gender. In addition to verifying the actual motor status, another objective was to verify the relationship between the variables employed.Basic statistical parameters show a distribution which is not significantly different from the normal distribution, yielded highly correlative values among the repetitive strength tests. Space factorization resulted in extracting two latent squares defined as repetitive strength of arms factor, and repetitive strength of body factor.

The Role of Phonological Working Memory and Environmental Factors in Lexical Development in Italian-Speaking Late Talkers: A One-Year Follow-Up Study.

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Marini, Andrea; Ruffino, Milena; Sali, Maria Enrica; Molteni, Massimo

2017-12-20

This follow-up study assessed (a) the influence of phonological working memory (pWM), home literacy environment, and a family history of linguistic impairments in late talkers (LTs); (b) the diagnostic accuracy of a task of nonword repetition (NWR) in identifying LTs; and (c) the persistence of lexical weaknesses after 10 months. Two hundred ninety-three children were assessed at approximately 32 (t1) and 41 (t2) months. At t1, they were administered the Italian adaptation of the Language Development Survey, an NWR task (used to assess pWM), and questionnaires assessing home literacy environment and family history of language impairments. Thirty-three LTs were identified. The linguistic skills of the participants were evaluated at t2 by administering tasks assessing Articulation, Naming, Semantic Fluency, and Lexical Comprehension. At t2, LTs performed more poorly as compared with age-matched typically developing peers in articulatory and naming skills, had reduced lexical comprehension abilities, and had limited lexical knowledge. Their performance on the NWR task at t1 correlated with the extension of their vocabularies at t2 (as estimated with a Semantic Fluency task). The Language Development Survey recently adapted to Italian is sensitive to LTs. Former LTs still have a mild lexical delay at approximately 40 months. As an indirect measure of pWM, the task of NWR is an early indicator of future lexical deficits.

The influences of task repetition, napping, time of day, and instruction on the Sustained Attention to Response Task

NARCIS (Netherlands)

Schie, M.K.M. van; Alblas, E.E.; Thijs, R.D.; Fronczek, R.; Lammers, G.J.; Dijk, J.G. van

2014-01-01

Introduction: The Sustained Attention to Response Task (SART) helps to quantify vigilance impairments. Previous studies, in which five SART sessions on one day were administered, demonstrated worse performance during the first session than during the others. The present study comprises two

Hebb repetition effects in visual memory: the roles of verbal rehearsal and distinctiveness.

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Horton, Neil; Hay, Dennis C; Smyth, Mary M

2008-01-01

A version of the Hebb repetition task was used with faces to explore the generality of the effect in a nonverbal domain. In the baseline condition, a series of upright faces was presented, and participants were asked to reconstruct the original order. Performance in this condition was compared to another in which the same stimuli were accompanied by concurrent verbal rehearsal to examine whether Hebb learning is dependent on verbal processing. Baseline performance was also compared to a condition in which the same faces were presented inverted. This comparison was used to determine the importance in Hebb learning of being able to visually distinguish between the list items. The results produced classic serial position curves that were equivalent over conditions with Hebb repetition effects being in evidence only for upright faces and verbal suppression as having no effect. These findings are interpreted as posing a challenge to current models derived from verbal-domain data.

Post-error expression of speed and force while performing a simple, monotonous task with a haptic pen

NARCIS (Netherlands)

Bruns, M.; Keyson, D.V.; Jabon, M.E.; Hummels, C.C.M.; Hekkert, P.P.M.; Bailenson, J.N.

2013-01-01

Control errors often occur in repetitive and monotonous tasks, such as manual assembly tasks. Much research has been done in the area of human error identification; however, most existing systems focus solely on the prediction of errors, not on increasing worker accuracy. The current study examines

Independent and Combined Effects of Socioeconomic Status (SES) and Bilingualism on Children's Vocabulary and Verbal Short-Term Memory.

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Meir, Natalia; Armon-Lotem, Sharon

2017-01-01

The current study explores the influence of socioeconomic status (SES) and bilingualism on the linguistic skills and verbal short-term memory of preschool children. In previous studies comparing children of low and mid-high SES, the terms "a child with low-SES" and "a child speaking a minority language" are often interchangeable, not enabling differentiated evaluation of these two variables. The present study controls for this confluence by testing children born and residing in the same country and attending the same kindergartens, with all bilingual children speaking the same heritage language (HL-Russian). A total of 120 children (88 bilingual children: 44 with low SES; and 32 monolingual children: 16 with low SES) with typical language development, aged 5; 7-6; 7, were tested in the societal language (SL-Hebrew) on expressive vocabulary and three repetition tasks [forward digit span (FWD), nonword repetition (NWR), and sentence repetition (SRep)], which tap into verbal short-term memory. The results indicated that SES and bilingualism impact different child abilities. Bilingualism is associated with decreased vocabulary size and lower performance on verbal short-term memory tasks with higher linguistic load in the SL-Hebrew. The negative effect of bilingualism on verbal short-term memory disappears once vocabulary is accounted for. SES influences not only linguistic performance, but also verbal short-term memory with lowest linguistic load. The negative effect of SES cannot be solely attributed to lower vocabulary scores, suggesting that an unprivileged background has a negative impact on children's cognitive development beyond a linguistic disadvantage. The results have important clinical implications and call for more research exploring the varied impact of language and life experience on children's linguistic and cognitive skills.

Reduced task-induced variations in the distribution of activity across back muscle regions in individuals with low back pain.

Science.gov (United States)

Falla, Deborah; Gizzi, Leonardo; Tschapek, Marika; Erlenwein, Joachim; Petzke, Frank

2014-05-01

This study investigated change in the distribution of lumbar erector spinae muscle activity and pressure pain sensitivity across the low back in individuals with low back pain (LBP) and healthy controls. Surface electromyographic (EMG) signals were recorded from multiple locations over the lumbar erector spinae muscle with a 13×5 grid of electrodes from 19 people with chronic nonspecific LBP and 17 control subjects as they performed a repetitive lifting task. The EMG root mean square (RMS) was computed for each location of the grid to form a map of the EMG amplitude distribution. Pressure pain thresholds (PPT) were recorded before and after the lifting task over a similar area of the back. For the control subjects, the EMG RMS progressively increased more in the caudal region of the lumbar erector spinae during the repetitive task, resulting in a shift in the distribution of muscle activity. In contrast, the distribution of muscle activity remained unaltered in the LBP group despite an overall increase in EMG amplitude. PPT was lower in the LBP group after completion of the repetitive task compared to baseline (average across all locations: pre: 268.0±165.9 kPa; post: 242.0±166.7 kPa), whereas no change in PPT over time was observed for the control group (320.1±162.1 kPa; post: 322.0±179.5 kPa). The results demonstrate that LBP alters the normal adaptation of lumbar erector spinae muscle activity to exercise, which occurs in the presence of exercise-induced hyperalgesia. Reduced variability of muscle activity may have important implications for the provocation and recurrence of LBP due to repetitive tasks. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Repetition and Emotive Communication in Music Versus Speech

Directory of Open Access Journals (Sweden)

Elizabeth Hellmuth eMargulis

2013-04-01

Full Text Available Music and speech are often placed alongside one another as comparative cases. Their relative overlaps and disassociations have been well explored (e.g. Patel, 2010. But one key attribute distinguishing these two domains has often been overlooked: the greater preponderance of repetition in music in comparison to speech. Recent fMRI studies have shown that familiarity – achieved through repetition – is a critical component of emotional engagement with music (Pereira et al., 2011. If repetition is fundamental to emotional responses to music, and repetition is a key distinguisher between the domains of music and speech, then close examination of the phenomenon of repetition might help clarify the ways that music elicits emotion differently than speech.

English as a Foreign Language in Bilingual Language-minority Children, Children with Dyslexia and Monolingual Typical Readers.

Science.gov (United States)

Bonifacci, Paola; Canducci, Elisa; Gravagna, Giulia; Palladino, Paola

2017-05-01

The present study was aimed at investigating literacy skills in English as a foreign language in three different groups of children: monolinguals with dyslexia (n = 19), typically developing bilinguals (language-minority) (n = 19) and a control group of monolinguals (Italian) (n = 76). Bilinguals were not expected to fail in English measures, and their gap with monolinguals would be expected to be limited to the instructional language, owing to underexposure. All participants were enrolled in Italian primary schools (fourth and fifth grades). A non-verbal reasoning task and Italian and English literacy tasks were administered. The Italian battery included word and non-word reading (speed and accuracy), word and non-word writing, and reading comprehension; the English battery included similar tasks, except for the non-word writing. Bilingual children performed similarly to typical readers in English tasks, whereas in Italian tasks, their performance was similar to that of typical readers in reading speed but not in reading accuracy and writing. Children with dyslexia underperformed compared with typically developing children in all English and Italian tasks, except for reading comprehension in Italian. Profile analysis and correlational analyses were further discussed. These results suggest that English as a foreign language might represent a challenge for students with dyslexia but a strength for bilingual language-minority children. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Feature-based motion control for near-repetitive structures

NARCIS (Netherlands)

Best, de J.J.T.H.

2011-01-01

In many manufacturing processes, production steps are carried out on repetitive structures which consist of identical features placed in a repetitive pattern. In the production of these repetitive structures one or more consecutive steps are carried out on the features to create the final product.

Transposed-letter priming of prelexical orthographic representations.

Science.gov (United States)

Kinoshita, Sachiko; Norris, Dennis

2009-01-01

A prime generated by transposing two internal letters (e.g., jugde) produces strong priming of the original word (judge). In lexical decision, this transposed-letter (TL) priming effect is generally weak or absent for nonword targets; thus, it is unclear whether the origin of this effect is lexical or prelexical. The authors describe the Bayesian Reader theory of masked priming (D. Norris & S. Kinoshita, 2008), which explains why nonwords do not show priming in lexical decision but why they do in the cross-case same-different task. This analysis is followed by 3 experiments that show that priming in this task is not based on low-level perceptual similarity between the prime and target, or on phonology, to make the case that priming is based on prelexical orthographic representation. The authors then use this task to demonstrate equivalent TL priming effects for nonwords and words. The results are interpreted as the first reliable evidence based on the masked priming procedure that letter position is not coded absolutely within the prelexical, orthographic representation. The implications of the results for current letter position coding schemes are discussed.

Kindergarten risk factors, cognitive factors, and teacher judgments as predictors of early reading in Dutch.

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Gijsel, Martine A R; Bosman, Anna M T; Verhoeven, Ludo

2006-01-01

This study focused on the predictive value of risk factors, cognitive factors, and teachers' judgments in a sample of 462 kindergartners for their early reading skills and reading failure at the beginning of Grade 1. With respect to risk factors, enrollment in speech-language therapy, history of dyslexia or speech-language problems in the family, and the role of gender were considered. None of these risk factors were significantly related to reading performance. Cognitive factors in this study included letter knowledge, rapid naming ability, and nonword repetition skills. Of these skills, letter knowledge seemed to have the highest correlation with reading. Kindergarten teachers' judgments, including a task assignment scale and teachers' predictions, demonstrated a significant relationship with reading. Finally, to judge whether these predictors could identify reading disabilities, the discriminatory power of all predictors was assessed and appeared to be insufficient. Implications for screening purposes are discussed.

Grade Repetition and Primary School Dropout in Uganda

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Kabay, Sarah

2016-01-01

Research on education in low-income countries rarely focuses on grade repetition. When addressed, repetition is typically presented along with early school dropout as the "wasting" of educational resources. Simplifying grade repetition in this way often fails to recognize significant methodological concerns and also overlooks the unique…

The Golden Ratio of Gait Harmony: Repetitive Proportions of Repetitive Gait Phases

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Marco Iosa

2013-01-01

Full Text Available In nature, many physical and biological systems have structures showing harmonic properties. Some of them were found related to the irrational number known as the golden ratio that has important symmetric and harmonic properties. In this study, the spatiotemporal gait parameters of 25 healthy subjects were analyzed using a stereophotogrammetric system with 25 retroreflective markers located on their skin. The proportions of gait phases were compared with , the value of which is about 1.6180. The ratio between the entire gait cycle and stance phase resulted in 1.620 ± 0.058, that between stance and the swing phase was 1.629 ± 0.173, and that between swing and the double support phase was 1.684 ± 0.357. All these ratios did not differ significantly from each other (, , repeated measure analysis of variance or from (, resp., t-tests. The repetitive gait phases of physiological walking were found in turn in repetitive proportions with each other, revealing an intrinsic harmonic structure. Harmony could be the key for facilitating the control of repetitive walking. Harmony is a powerful unifying factor between seemingly disparate fields of nature, including human gait.

The effects of previewing questions, repetition of input, and topic preparation on listening comprehension of Iranian EFL learners

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Afsar Rouhi

2014-07-01

Full Text Available In this study, an attempt was made to examine the effects of previewing questions, repetition of input, and topic preparation on listening comprehension of Iranian learners of English. The study was conducted with 104 high school students in 3 experimental and one control groups. The participants in the previewing questions group read the comprehension questions before hearing the text and answering the questions. The topic preparation group took advantage of topic-related texts in Persian followed by previewing questions; then they listened to the texts and answered the questions. The repetition of input group had two hearings with previewing before each hearing that preceded answering the comprehension questions. The control group, however, only had one hearing before answering the questions. The results obtained from data analysis showed that the topic preparation group performed better than the other participating groups. The repetition group, in turn, did better than the previewing group. There was, however, no statistically significant difference between the previewing and repetition groups. Based on the results obtained, it can be argued that providing and/or activating background knowledge and repeating a listening task might facilitate listening comprehension in EFL classroom settings. The findings and pedagogical implications of the study are discussed in detail.

Verbal behavior in Alzheimer's disease patients: Analysis of phrase repetition.

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Cecato, Juliana Francisca; Martinellil, José Eduardo; Bartholomeu, Luana Luz; Basqueira, Ana Paula; Yassuda, Mônica Sanches; Aprahamian, Ivan

2010-01-01

Language problems in the elderly with AD are due to the fact that deterioration occurs not only in semantic memory, but in a group of cognitive factors, evidenced by a deficiency in search strategies for linguistic information. To evaluate phrase repetition in two cognitive tests, the MMSE and MoCA, in a group of Alzheimer disease patients (AD) and normal controls. A Cross-sectional study was conducted involving 20 patients who sought medical assistance at a geriatric institute in Jundiaí, São Paulo. The subjects underwent a detailed clinical examination and neuropsychometric evaluation. All subjects with AD met DSM-IV and NINCDS-ADRDA criteria. Ten patients received a diagnosis of AD and 10 were healthy subjects, forming the control group (CG). All participants correctly answered the phrase from the MMSE (phrase 1). The MoCA phrases (phrases 2 and 3) were correct in 80% and 90%, respectively in the CG and in 40% and 50%, respectively in the AD group. The MoCA test proved more effective in evaluating the echoic behavior in AD patients compared to the MMSE. The simpler phrase repetition task in the MMSE was found to be less sensitive in detecting mild language decline in AD patients.

Verbal behavior in Alzheimer disease patients: Analysis of phrase repetition

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Juliana Francisca Cecato

Full Text Available Abstract Language problems in the elderly with AD are due to the fact that deterioration occurs not only in semantic memory, but in a group of cognitive factors, evidenced by a deficiency in search strategies for linguistic information. Objectives: To evaluate phrase repetition in two cognitive tests, the MMSE and MoCA, in a group of Alzheimer disease patients (AD and normal controls. Methods: A Cross-sectional study was conducted involving 20 patients who sought medical assistance at a geriatric institute in Jundiaí, São Paulo. The subjects underwent a detailed clinical examination and neuropsychometric evaluation. All subjects with AD met DSM-IV and NINCDS-ADRDA criteria. Ten patients received a diagnosis of AD and 10 were healthy subjects, forming the control group (CG. Results: All participants correctly answered the phrase from the MMSE (phrase 1. The MoCA phrases (phrases 2 and 3 were correct in 80% and 90%, respectively in the CG and in 40% and 50%, respectively in the AD group. Conclusions: The MoCA test proved more effective in evaluating the echoic behavior in AD patients compared to the MMSE. The simpler phrase repetition task in the MMSE was found to be less sensitive in detecting mild language decline in AD patients.

Interactional leader–follower sensorimotor communication strategies during repetitive joint actions

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Candidi, Matteo; Curioni, Arianna; Donnarumma, Francesco; Sacheli, Lucia Maria; Pezzulo, Giovanni

2015-01-01

Non-verbal communication is the basis of animal interactions. In dyadic leader–follower interactions, leaders master the ability to carve their motor behaviour in order to ‘signal’ their future actions and internal plans while these signals influence the behaviour of follower partners, who automatically tend to imitate the leader even in complementary interactions. Despite their usefulness, signalling and imitation have a biomechanical cost, and it is unclear how this cost–benefits trade-off is managed during repetitive dyadic interactions that present learnable regularities. We studied signalling and imitation dynamics (indexed by movement kinematics) in pairs of leaders and followers during a repetitive, rule-based, joint action. Trial-by-trial Bayesian model comparison was used to evaluate the relation between signalling, imitation and pair performance. The different models incorporate different hypotheses concerning the factors (past interactions versus online movements) influencing the leader's signalling (or follower's imitation) kinematics. This approach showed that (i) leaders' signalling strategy improves future couple performance, (ii) leaders used the history of past interactions to shape their signalling, (iii) followers' imitative behaviour is more strongly affected by the online movement of the leader. This study elucidates the ways online sensorimotor communication help individuals align their task representations and ultimately improves joint action performance. PMID:26333815

Global Repetition Influences Contextual Cueing

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Zang, Xuelian; Zinchenko, Artyom; Jia, Lina; Li, Hong

2018-01-01

Our visual system has a striking ability to improve visual search based on the learning of repeated ambient regularities, an effect named contextual cueing. Whereas most of the previous studies investigated contextual cueing effect with the same number of repeated and non-repeated search displays per block, the current study focused on whether a global repetition frequency formed by different presentation ratios between the repeated and non-repeated configurations influence contextual cueing effect. Specifically, the number of repeated and non-repeated displays presented in each block was manipulated: 12:12, 20:4, 4:20, and 4:4 in Experiments 1–4, respectively. The results revealed a significant contextual cueing effect when the global repetition frequency is high (≥1:1 ratio) in Experiments 1, 2, and 4, given that processing of repeated displays was expedited relative to non-repeated displays. Nevertheless, the contextual cueing effect reduced to a non-significant level when the repetition frequency reduced to 4:20 in Experiment 3. These results suggested that the presentation frequency of repeated relative to the non-repeated displays could influence the strength of contextual cueing. In other words, global repetition statistics could be a crucial factor to mediate contextual cueing effect. PMID:29636716

Imbalance between abstract and concrete repetitive thinking modes in schizophrenia.

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Maurage, Pierre; Philippot, Pierre; Grynberg, Delphine; Leleux, Dominique; Delatte, Benoît; Mangelinckx, Camille; Belge, Jan-Baptist; Constant, Eric

2017-10-01

Repetitive thoughts can be divided in two modes: abstract/analytic (decontextualized and dysfunctional) and concrete/experiential (problem-focused and adaptive). They constitute a transdiagnostic process involved in many psychopathological states but have received little attention in schizophrenia, as earlier studies only indexed increased ruminations (related to dysfunctional repetitive thoughts) without jointly exploring both modes. This study explored the two repetitive thinking modes, beyond ruminations, to determine their imbalance in schizophrenia. Thirty stabilized patients with schizophrenia and 30 matched controls completed the Repetitive Response Scale and the Mini Cambridge-Exeter Repetitive Thought Scale, both measuring repetitive thinking modes. Complementary measures related to schizophrenic symptomatology, depression and anxiety were also conducted. Compared to controls, patients with schizophrenia presented an imbalance between repetitive thinking modes, with increased abstract/analytic and reduced concrete/experiential thoughts, even after controlling for comorbidities. Schizophrenia is associated with stronger dysfunctional repetitive thoughts (i.e. abstract thinking) and impaired ability to efficiently use repetitive thinking for current problem-solving (i.e. concrete thinking). This imbalance confirms the double-faced nature of repetitive thinking modes, whose influence on schizophrenia's symptomatology should be further investigated. The present results also claim for evaluating these processes in clinical settings and for rehabilitating the balance between opposite repetitive thinking modes. Copyright © 2017 Elsevier Inc. All rights reserved.

Repetition blindness has a perceptual locus: evidence from online processing of targets in RSVP streams

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Johnston, James C.; Hochhaus, Larry; Ruthruff, Eric

2002-01-01

Four experiments tested whether repetition blindness (RB; reduced accuracy reporting repetitions of briefly displayed items) is a perceptual or a memory-recall phenomenon. RB was measured in rapid serial visual presentation (RSVP) streams, with the task altered to reduce memory demands. In Experiment 1 only the number of targets (1 vs. 2) was reported, eliminating the need to remember target identities. Experiment 2 segregated repeated and nonrepeated targets into separate blocks to reduce bias against repeated targets. Experiments 3 and 4 required immediate "online" buttonpress responses to targets as they occurred. All 4 experiments showed very strong RB. Furthermore, the online response data showed clearly that the 2nd of the repeated targets is the one missed. The present results show that in the RSVP paradigm, RB occurs online during initial stimulus encoding and decision making. The authors argue that RB is indeed a perceptual phenomenon.

The effects of foreknowledge and task-set shifting as mirrored in cue- and target-locked event-related potentials.

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Mareike Finke

Full Text Available The present study examined the use of foreknowledge in a task-cueing protocol while manipulating sensory updating and executive control in both, informatively and non-informatively pre-cued trials. Foreknowledge, sensory updating (cue switch effects and task-switching were orthogonally manipulated in order to address the question of whether, and to which extent, the sensory processing of cue changes can partly or totally explain the final task switch costs. Participants responded faster when they could prepare for the upcoming task and if no task-set updating was necessary. Sensory cue switches influenced cue-locked ERPs only when they contained conceptual information about the upcoming task: frontal P2 amplitudes were modulated by task-relevant cue changes, mid-parietal P3 amplitudes by the anticipatory updating of stimulus-response mappings, and P3 peak latencies were modulated by task switching. Task preparation was advantageous for efficient stimulus-response re-mapping at target-onset as mirrored in target N2 amplitudes. However, N2 peak latencies indicate that this process is faster for all repeat trials. The results provide evidence to support a very fast detection of task-relevance in sensory (cue changes and argue against the view of task repetition benefits as secondary to purely perceptual repetition priming. Advanced preparation may have a stronger influence on behavioral performance and target-locked brain activity than the local effect of repeating or switching the task-set in the current trial.

Chronic repetitive reaching and grasping results in decreased motor performance and widespread tissue responses in a rat model of MSD.

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Barbe, Mary F; Barr, Ann E; Gorzelany, Irene; Amin, Mamta; Gaughan, John P; Safadi, Fayez F

2003-01-01

This study investigated changes in motor skills and tissues of the upper extremity (UE) with regard to injury and inflammatory reactions resulting from performance of a voluntary forelimb repetitive reaching and grasping task in rats. Rats reached for food at a rate of 4 reaches/min, 2 h/day, and 3 days/week for up to 8 weeks during which reach rate, task duration and movement strategies were observed. UE tissues were collected bilaterally at weekly time points of 3-8 weeks and examined for morphological changes. Serum was tested for levels of interleukin-1alpha (IL-1) protein. The macrophage-specific antibody, ED1, was used to identify infiltrating macrophages and the ED2 antibody was used to identify resident macrophages. Rats were unable to maintain baseline reach rate in weeks 5 and 6 of task performance. Alternative patterns of movement emerged. Fraying of tendon fibrils was observed after 6 weeks in the mid-forelimb. After 4 weeks, a general elevation of ED1-IR macrophages were seen in all tissues examined bilaterally including the contralateral, uninvolved forelimb and hindlimbs. Significantly more resident macrophages were seen at 6 and 8 weeks in the reach limb. At 8 weeks, serum levels of IL-1alpha increased significantly above week 0. Our results demonstrate that performance of repetitive tasks elicits motor decrements, signs of injury and a cellular and tissue responses associated with inflammation.

Nonfunctional Redundant Acts Characterize OCD, Even in OCD-Unrelated Tasks: A Demonstration in Questionnaire Completion.

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Amitai, Maya; Arnon, Nitzan; Shaham, Noa; Gur, Shay; Apter, Alan; Weizman, Abraham; Hermesh, Haggai

2017-01-01

Ethological methods used to analyze human obsessive-compulsive disorder (OCD) rituals demonstrated excess of unnecessary repetitions as well as irrelevant, idiosyncratic acts (additions) compared to normal activity. A question that still remains is whether these well-known repetitions and additions are manifested in behaviors unrelated to the OCD rituals. Our objectives were to: (1) assess whether OCD-related repetitions and additions as found in previous studies also affect the patients' activity of filling out questionnaires and (2) evaluate the specificity of these behaviors to OCD as opposed to other anxiety disorders and healthy controls. Several standardized disorder-specific self-report questionnaires were used in order to assess the patient's psychopathologies. The style of filling-out these questionnaires by OCD and non-OCD anxiety outpatients and normal controls was analyzed. Four categories were used: omissions, repetitions, corrections, and additions. The OCD group scored significantly higher on the number of additions as compared with both the anxiety group and the nonclinical group, and significantly higher on the number of corrections and repetitions as compared with the nonclinical group. The hallmarks of OCD, repetitions and additions, are manifested not only in the patient's rituals and thoughts, but in apparently "neutral" tasks that do not a priori involve the intrusive thoughts, urges, and images typical of obsessive-compulsive behavior. Additions seem to be more specific to OCD than repetitions. These two executive faults impede routine functionality of OCD patients in tasks related and unrelated to their rituals. Our study delineates simple, observable behavioral characteristics that distinguish between OCD and non-OCD anxiety patients as well as healthy individuals. These symptomatic behaviors may offer a clue to personality traits or deficits in executive functions that possibly play a part in the pathophysiology of OCD. Our results are an

Repetitive thinking, executive functioning, and depressive mood in the elderly.

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Philippot, Pierre; Agrigoroaei, Stefan

2017-11-01

Previous findings and the depressive-executive dysfunction hypothesis suggest that the established association between executive functioning and depression is accounted for by repetitive thinking. Investigating the association between executive functioning, repetitive thinking, and depressive mood, the present study empirically tested this mediational model in a sample of older adults, while focusing on both concrete and abstract repetitive thinking. This latter distinction is important given the potential protective role of concrete repetitive thinking, in contrast to the depletive effect of abstract repetitive thinking. A sample of 43 elderly volunteers, between 75 and 95 years of age, completed tests of executive functioning (the Stroop test, the Trail Making test, and the Fluency test), and questionnaires of repetitive thinking and depression. Positive correlations were observed between abstract repetitive thinking and depressive mood, and between concrete repetitive thinking and executive functioning; a negative correlation was observed between depressive mood and executive functioning. Further, mediational analysis evidenced that the relation between executive functioning and depressive mood was mediated by abstract repetitive thinking. The present data provide, for the first time, empirical support to the depressive-executive dysfunction hypothesis: the lack of executive resources would favor a mode of abstract repetitive thinking, which in turn would deplete mood. It suggests that clinical intervention targeting depression in the elderly should take into consideration repetitive thinking modes and the executive resources needed to disengage from rumination.

Discomforts of tasks video users: The case of workers of ENEA area in Bologna (Italy)

International Nuclear Information System (INIS)

Cenni, P.; Varasano, R.; Cavallaro, E.; Arduini, R.; Mattioli, S.; Tuozzi, G.

1996-08-01

The aim of this study is to investigate the subjective musculoskeletal discomfort in a sample of 334 workers (204 males and 130 females) of the ENEA area in Bologna, using for different periods and tasks video display units (VDU). On a preliminary self report questionnaire the workers have reported: hours at VDU per day, type of task type of hardware, physical-ergonomic environmental conditions, equipment and layout of the work station. Then, on a case-history form, the researcher has recorded for each subject: anamnesis, fatigue symptoms, discomfort and pain perceived in the back, shoulder, hand and arm regions. The results have shown that, in this sample, the main cause for potential musculoskeletal problems is related to aging whereas the women mainly engaged in repetitive jobs seem to be more likely subject to these troubles. About the correlation between type of task and musculoskeletal discomfort, the females refer more complaints than the males, especially when the task is repetitive. Also the number of hours spent at VDU per day is higher in the females. Finally, about physical-ergonomic environmental conditions, most users have not referred discomforts related to lighting, noise, micro climate or to work station (equipment and layout)

MAXIMUM NUMBER OF REPETITIONS, TOTAL WEIGHT LIFTED AND NEUROMUSCULAR FATIGUE IN INDIVIDUALS WITH DIFFERENT TRAINING BACKGROUNDS

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Valeria Panissa

2013-04-01

Full Text Available The aim of this study was to evaluate the performance, as well as neuromuscular activity, in a strength task in subjects with different training backgrounds. Participants (n = 26 were divided into three groups according to their training backgrounds (aerobic, strength or mixed and submitted to three sessions: (1 determination of the maximum oxygen uptake during the incremental treadmill test to exhaustion and familiarization of the evaluation of maximum strength (1RM for the half squat; (2 1RM determination; and (3 strength exercise, four sets at 80�0of the 1RM, in which the maximum number of repetitions (MNR, the total weight lifted (TWL, the root mean square (RMS and median frequency (MF of the electromyographic (EMG activity for the second and last repetition were computed. There was an effect of group for MNR, with the aerobic group performing a higher MNR compared to the strength group (P = 0.045, and an effect on MF with a higher value in the second repetition than in the last repetition (P = 0.016. These results demonstrated that individuals with better aerobic fitness were more fatigue resistant than strength trained individuals. The absence of differences in EMG signals indicates that individuals with different training backgrounds have a similar pattern of motor unit recruitment during a resistance exercise performed until failure, and that the greater capacity to perform the MNR probably can be explained by peripheral adaptations.

The Effect of Enumeration of Self-Relevant Words on Self-Focused Attention and Repetitive Negative Thoughts

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Muranaka, Seiji; Sasaki, Jun

2018-01-01

Self-focused attention refers to awareness of self-referent, internally generated information. It can be categorized into dysfunctional (i.e., self-rumination) and functional (self-reflection) aspects. According to theory on cognitive resource limitations (e.g., Moreno, 2006), there is a difference in cognitive resource allocation between these two aspects of self-focused attention. We propose a new task, self-relevant word (SRW) enumeration, that can aid in behaviorally identifying individuals’ use of self-rumination and self-reflection. The present study has two purposes: to determine the association between self-focus and SRW enumeration, and to examine the effect of dysfunctional SRW enumeration on repetitive negative thinking. One hundred forty-six undergraduate students participated in this study. They completed a measure of state anxiety twice, before and after imagining a social failure situation. They also completed the SRW enumeration task, Repetitive Thinking Questionnaire, Short Fear of Negative Evaluation Scale, and Rumination-Reflection Questionnaire. A correlational analysis indicated a significant positive correlation between self-reflection and the number of SRWs. Furthermore, individuals high in self-reflection had a tendency to pay more attention to problems than did those high in self-rumination. A significant positive correlation was found between self-rumination and the strength of self-relevance of negative SRWs. Through a path analysis, we found a significant positive effect of the self-relevance of negative SRWs on repetitive negative thinking. Notably, however, the model that excluded self-rumination as an explanatory variable showed a better fit to the data than did the model that included it. In summary, SRW enumeration might enable selective and independent detection of the degree of self-reflection and self-rumination, and therefore should be examined in future research in order to design new behavioral procedures. PMID:29896140

The Effect of Enumeration of Self-Relevant Words on Self-Focused Attention and Repetitive Negative Thoughts

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Seiji Muranaka

2018-05-01

Full Text Available Self-focused attention refers to awareness of self-referent, internally generated information. It can be categorized into dysfunctional (i.e., self-rumination and functional (self-reflection aspects. According to theory on cognitive resource limitations (e.g., Moreno, 2006, there is a difference in cognitive resource allocation between these two aspects of self-focused attention. We propose a new task, self-relevant word (SRW enumeration, that can aid in behaviorally identifying individuals’ use of self-rumination and self-reflection. The present study has two purposes: to determine the association between self-focus and SRW enumeration, and to examine the effect of dysfunctional SRW enumeration on repetitive negative thinking. One hundred forty-six undergraduate students participated in this study. They completed a measure of state anxiety twice, before and after imagining a social failure situation. They also completed the SRW enumeration task, Repetitive Thinking Questionnaire, Short Fear of Negative Evaluation Scale, and Rumination-Reflection Questionnaire. A correlational analysis indicated a significant positive correlation between self-reflection and the number of SRWs. Furthermore, individuals high in self-reflection had a tendency to pay more attention to problems than did those high in self-rumination. A significant positive correlation was found between self-rumination and the strength of self-relevance of negative SRWs. Through a path analysis, we found a significant positive effect of the self-relevance of negative SRWs on repetitive negative thinking. Notably, however, the model that excluded self-rumination as an explanatory variable showed a better fit to the data than did the model that included it. In summary, SRW enumeration might enable selective and independent detection of the degree of self-reflection and self-rumination, and therefore should be examined in future research in order to design new behavioral procedures.

Auditory-visual integration modulates location-specific repetition suppression of auditory responses.

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Shrem, Talia; Murray, Micah M; Deouell, Leon Y

2017-11-01

Space is a dimension shared by different modalities, but at what stage spatial encoding is affected by multisensory processes is unclear. Early studies observed attenuation of N1/P2 auditory evoked responses following repetition of sounds from the same location. Here, we asked whether this effect is modulated by audiovisual interactions. In two experiments, using a repetition-suppression paradigm, we presented pairs of tones in free field, where the test stimulus was a tone presented at a fixed lateral location. Experiment 1 established a neural index of auditory spatial sensitivity, by comparing the degree of attenuation of the response to test stimuli when they were preceded by an adapter sound at the same location versus 30° or 60° away. We found that the degree of attenuation at the P2 latency was inversely related to the spatial distance between the test stimulus and the adapter stimulus. In Experiment 2, the adapter stimulus was a tone presented from the same location or a more medial location than the test stimulus. The adapter stimulus was accompanied by a simultaneous flash displayed orthogonally from one of the two locations. Sound-flash incongruence reduced accuracy in a same-different location discrimination task (i.e., the ventriloquism effect) and reduced the location-specific repetition-suppression at the P2 latency. Importantly, this multisensory effect included topographic modulations, indicative of changes in the relative contribution of underlying sources across conditions. Our findings suggest that the auditory response at the P2 latency is affected by spatially selective brain activity, which is affected crossmodally by visual information. © 2017 Society for Psychophysiological Research.

Comparing kinematic changes between a finger-tapping task and unconstrained finger flexion-extension task in patients with Parkinson's disease.

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Teo, W P; Rodrigues, J P; Mastaglia, F L; Thickbroom, G W

2013-06-01

Repetitive finger tapping is a well-established clinical test for the evaluation of parkinsonian bradykinesia, but few studies have investigated other finger movement modalities. We compared the kinematic changes (movement rate and amplitude) and response to levodopa during a conventional index finger-thumb-tapping task and an unconstrained index finger flexion-extension task performed at maximal voluntary rate (MVR) for 20 s in 11 individuals with levodopa-responsive Parkinson's disease (OFF and ON) and 10 healthy age-matched controls. Between-task comparisons showed that for all conditions, the initial movement rate was greater for the unconstrained flexion-extension task than the tapping task. Movement rate in the OFF state was slower than in controls for both tasks and normalized in the ON state. The movement amplitude was also reduced for both tasks in OFF and increased in the ON state but did not reach control levels. The rate and amplitude of movement declined significantly for both tasks under all conditions (OFF/ON and controls). The time course of rate decline was comparable for both tasks and was similar in OFF/ON and controls, whereas the tapping task was associated with a greater decline in MA, both in controls and ON, but not OFF. The findings indicate that both finger movement tasks show similar kinematic changes during a 20-s sustained MVR, but that movement amplitude is less well sustained during the tapping task than the unconstrained finger movement task. Both movement rate and amplitude improved with levodopa; however, movement rate was more levodopa responsive than amplitude.

Can we use neurocognition to predict repetition of self-harm, and why might this be clinically useful? A perspective.

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Angharad Natalie De Cates

2016-01-01

Full Text Available Over 800,000 people die by suicide each year globally, with non-fatal self-harm 20 times more common. With each episode of self-harm, the risks of future self-harm and suicide increase, as well as personal and healthcare costs. Therefore, early delineation of those at high-risk of future self-harm is important. Historically, research has focused on clinical and demographic factors, but risk assessments based on these have low sensitivity to predict repetition. Various neurocognitive factors have been associated with self-harming behavior, but it is less certain if we can use these factors clinically (i as risk markers to predict future self-harm and (ii to become therapeutic targets for interventions.Recent systematic reviews and meta-analyses of behavioral tasks and fMRI studies point to an emerging hypothesis for neurocognition in self-harm: an underactive pre-frontal cortex is unable to respond appropriately to non-emotional stimuli, or inhibit a hyperactive emotionally- / threat-driven limbic system. However, there is almost no imaging data examining repetition of self-harm. Extrapolating from the non-repetition data, there may be several potential neurocognitive targets for interventions to prevent repeat self-harm: cognitive training; pharmacological regimes to promote non-emotional neurocognition; or other techniques, such as repetitive transcranial magnetic stimulation (rTMS. Hence, there is an urgent need for imaging studies examining repetition and to test specific hypotheses. Until we investigate the functional neurocognitive basis underlying repetition of self-harm in a systematic manner using second-generational imaging techniques, we will be unable to inform third-generational imaging and potential future clinical applications.

Directed PCR-free engineering of highly repetitive DNA sequences

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Preissler Steffen

2011-09-01

Full Text Available Abstract Background Highly repetitive nucleotide sequences are commonly found in nature e.g. in telomeres, microsatellite DNA, polyadenine (poly(A tails of eukaryotic messenger RNA as well as in several inherited human disorders linked to trinucleotide repeat expansions in the genome. Therefore, studying repetitive sequences is of biological, biotechnological and medical relevance. However, cloning of such repetitive DNA sequences is challenging because specific PCR-based amplification is hampered by the lack of unique primer binding sites resulting in unspecific products. Results For the PCR-free generation of repetitive DNA sequences we used antiparallel oligonucleotides flanked by restriction sites of Type IIS endonucleases. The arrangement of recognition sites allowed for stepwise and seamless elongation of repetitive sequences. This facilitated the assembly of repetitive DNA segments and open reading frames encoding polypeptides with periodic amino acid sequences of any desired length. By this strategy we cloned a series of polyglutamine encoding sequences as well as highly repetitive polyadenine tracts. Such repetitive sequences can be used for diverse biotechnological applications. As an example, the polyglutamine sequences were expressed as His6-SUMO fusion proteins in Escherichia coli cells to study their aggregation behavior in vitro. The His6-SUMO moiety enabled affinity purification of the polyglutamine proteins, increased their solubility, and allowed controlled induction of the aggregation process. We successfully purified the fusions proteins and provide an example for their applicability in filter retardation assays. Conclusion Our seamless cloning strategy is PCR-free and allows the directed and efficient generation of highly repetitive DNA sequences of defined lengths by simple standard cloning procedures.

Comparing different kinds of words and word-word relations to test an habituation model of priming.

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Rieth, Cory A; Huber, David E

2017-06-01

Huber and O'Reilly (2003) proposed that neural habituation exists to solve a temporal parsing problem, minimizing blending between one word and the next when words are visually presented in rapid succession. They developed a neural dynamics habituation model, explaining the finding that short duration primes produce positive priming whereas long duration primes produce negative repetition priming. The model contains three layers of processing, including a visual input layer, an orthographic layer, and a lexical-semantic layer. The predicted effect of prime duration depends both on this assumed representational hierarchy and the assumption that synaptic depression underlies habituation. The current study tested these assumptions by comparing different kinds of words (e.g., words versus non-words) and different kinds of word-word relations (e.g., associative versus repetition). For each experiment, the predictions of the original model were compared to an alternative model with different representational assumptions. Experiment 1 confirmed the prediction that non-words and inverted words require longer prime durations to eliminate positive repetition priming (i.e., a slower transition from positive to negative priming). Experiment 2 confirmed the prediction that associative priming increases and then decreases with increasing prime duration, but remains positive even with long duration primes. Experiment 3 replicated the effects of repetition and associative priming using a within-subjects design and combined these effects by examining target words that were expected to repeat (e.g., viewing the target word 'BACK' after the prime phrase 'back to'). These results support the originally assumed representational hierarchy and more generally the role of habituation in temporal parsing and priming. Copyright © 2017 Elsevier Inc. All rights reserved.

Enhanced accuracy in novel mirror drawing after repetitive transcranial magnetic stimulation-induced proprioceptive deafferentation

DEFF Research Database (Denmark)

Balslev, Daniela; Christensen, Lars O.D.; Lee, Ji-hang

2004-01-01

a performance benefit. In this study, we tested whether deafferentation induced by repetitive transcranial magnetic stimulation (rTMS) can improve mirror tracing skills in normal subjects. Hand trajectory error during novel mirror drawing was compared across two groups of subjects that received either 1 Hz r......TMS over the somatosensory cortex contralateral to the hand or sham stimulation. Mirror tracing was more accurate after rTMS than after sham stimulation. Using a position-matching task, we confirmed that rTMS reduced proprioceptive acuity and that this reduction was largest when the coil was placed...

Sequential Modulations in a Combined Horizontal and Vertical Simon Task: Is There ERP Evidence for Feature Integration Effects?

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Hoppe, Katharina; Küper, Kristina; Wascher, Edmund

2017-01-01

In the Simon task, participants respond faster when the task-irrelevant stimulus position and the response position are corresponding, for example on the same side, compared to when they have a non-corresponding relation. Interestingly, this Simon effect is reduced after non-corresponding trials. Such sequential effects can be explained in terms of a more focused processing of the relevant stimulus dimension due to increased cognitive control, which transfers from the previous non-corresponding trial (conflict adaptation effects). Alternatively, sequential modulations of the Simon effect can also be due to the degree of trial-to-trial repetitions and alternations of task features, which is confounded with the correspondence sequence (feature integration effects). In the present study, we used a spatially two-dimensional Simon task with vertical response keys to examine the contribution of adaptive cognitive control and feature integration processes to the sequential modulation of the Simon effect. The two-dimensional Simon task creates correspondences in the vertical as well as in the horizontal dimension. A trial-by-trial alternation of the spatial dimension, for example from a vertical to a horizontal stimulus presentation, generates a subset containing no complete repetitions of task features, but only complete alternations and partial repetitions, which are equally distributed over all correspondence sequences. In line with the assumed feature integration effects, we found sequential modulations of the Simon effect only when the spatial dimension repeated. At least for the horizontal dimension, this pattern was confirmed by the parietal P3b, an event-related potential that is assumed to reflect stimulus-response link processes. Contrary to conflict adaptation effects, cognitive control, measured by the fronto-central N2 component of the EEG, was not sequentially modulated. Overall, our data provide behavioral as well as electrophysiological evidence for feature

The Interdependence of Long- and Short-Term Components in Unmasked Repetition Priming: An Indication of Shared Resources.

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Merema, Matt R; Speelman, Craig P

2015-01-01

It has been suggested that unmasked repetition priming is composed of distinct long-and short-term priming components. The current study sought to clarify the relationship between these components by examining the relationship between them. A total of 60 people (45 females, 15 males) participated in a computer-based lexical decision task designed to measure levels of short-term priming across different levels of long-term priming. The results revealed an interdependent relationship between the two components, whereby an increase in long-term priming prompted a decrease in short-term priming. Both long-term and short-term priming were accurately captured by a single power function over seven minutes post repetition, suggesting the two components may draw on the same resources. This interdependence between long- and short-term priming may serve to improve fluency in reading.

The Interdependence of Long- and Short-Term Components in Unmasked Repetition Priming: An Indication of Shared Resources.

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Matt R Merema

Full Text Available It has been suggested that unmasked repetition priming is composed of distinct long-and short-term priming components. The current study sought to clarify the relationship between these components by examining the relationship between them. A total of 60 people (45 females, 15 males participated in a computer-based lexical decision task designed to measure levels of short-term priming across different levels of long-term priming. The results revealed an interdependent relationship between the two components, whereby an increase in long-term priming prompted a decrease in short-term priming. Both long-term and short-term priming were accurately captured by a single power function over seven minutes post repetition, suggesting the two components may draw on the same resources. This interdependence between long- and short-term priming may serve to improve fluency in reading.

Independent and Combined Effects of Socioeconomic Status (SES) and Bilingualism on Children’s Vocabulary and Verbal Short-Term Memory

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Meir, Natalia; Armon-Lotem, Sharon

2017-01-01

The current study explores the influence of socioeconomic status (SES) and bilingualism on the linguistic skills and verbal short-term memory of preschool children. In previous studies comparing children of low and mid-high SES, the terms “a child with low-SES” and “a child speaking a minority language” are often interchangeable, not enabling differentiated evaluation of these two variables. The present study controls for this confluence by testing children born and residing in the same country and attending the same kindergartens, with all bilingual children speaking the same heritage language (HL-Russian). A total of 120 children (88 bilingual children: 44 with low SES; and 32 monolingual children: 16 with low SES) with typical language development, aged 5; 7–6; 7, were tested in the societal language (SL-Hebrew) on expressive vocabulary and three repetition tasks [forward digit span (FWD), nonword repetition (NWR), and sentence repetition (SRep)], which tap into verbal short-term memory. The results indicated that SES and bilingualism impact different child abilities. Bilingualism is associated with decreased vocabulary size and lower performance on verbal short-term memory tasks with higher linguistic load in the SL-Hebrew. The negative effect of bilingualism on verbal short-term memory disappears once vocabulary is accounted for. SES influences not only linguistic performance, but also verbal short-term memory with lowest linguistic load. The negative effect of SES cannot be solely attributed to lower vocabulary scores, suggesting that an unprivileged background has a negative impact on children’s cognitive development beyond a linguistic disadvantage. The results have important clinical implications and call for more research exploring the varied impact of language and life experience on children’s linguistic and cognitive skills. PMID:28890706

Independent and Combined Effects of Socioeconomic Status (SES and Bilingualism on Children’s Vocabulary and Verbal Short-Term Memory

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Natalia Meir

2017-08-01

Full Text Available The current study explores the influence of socioeconomic status (SES and bilingualism on the linguistic skills and verbal short-term memory of preschool children. In previous studies comparing children of low and mid-high SES, the terms “a child with low-SES” and “a child speaking a minority language” are often interchangeable, not enabling differentiated evaluation of these two variables. The present study controls for this confluence by testing children born and residing in the same country and attending the same kindergartens, with all bilingual children speaking the same heritage language (HL-Russian. A total of 120 children (88 bilingual children: 44 with low SES; and 32 monolingual children: 16 with low SES with typical language development, aged 5; 7–6; 7, were tested in the societal language (SL-Hebrew on expressive vocabulary and three repetition tasks [forward digit span (FWD, nonword repetition (NWR, and sentence repetition (SRep], which tap into verbal short-term memory. The results indicated that SES and bilingualism impact different child abilities. Bilingualism is associated with decreased vocabulary size and lower performance on verbal short-term memory tasks with higher linguistic load in the SL-Hebrew. The negative effect of bilingualism on verbal short-term memory disappears once vocabulary is accounted for. SES influences not only linguistic performance, but also verbal short-term memory with lowest linguistic load. The negative effect of SES cannot be solely attributed to lower vocabulary scores, suggesting that an unprivileged background has a negative impact on children’s cognitive development beyond a linguistic disadvantage. The results have important clinical implications and call for more research exploring the varied impact of language and life experience on children’s linguistic and cognitive skills.

Negative effects of item repetition on source memory.

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Kim, Kyungmi; Yi, Do-Joon; Raye, Carol L; Johnson, Marcia K

2012-08-01

In the present study, we explored how item repetition affects source memory for new item-feature associations (picture-location or picture-color). We presented line drawings varying numbers of times in Phase 1. In Phase 2, each drawing was presented once with a critical new feature. In Phase 3, we tested memory for the new source feature of each item from Phase 2. Experiments 1 and 2 demonstrated and replicated the negative effects of item repetition on incidental source memory. Prior item repetition also had a negative effect on source memory when different source dimensions were used in Phases 1 and 2 (Experiment 3) and when participants were explicitly instructed to learn source information in Phase 2 (Experiments 4 and 5). Importantly, when the order between Phases 1 and 2 was reversed, such that item repetition occurred after the encoding of critical item-source combinations, item repetition no longer affected source memory (Experiment 6). Overall, our findings did not support predictions based on item predifferentiation, within-dimension source interference, or general interference from multiple traces of an item. Rather, the findings were consistent with the idea that prior item repetition reduces attention to subsequent presentations of the item, decreasing the likelihood that critical item-source associations will be encoded.

Barriers to critical thinking: workflow interruptions and task switching among nurses.

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Cornell, Paul; Riordan, Monica; Townsend-Gervis, Mary; Mobley, Robin

2011-10-01

Nurses are increasingly called upon to engage in critical thinking. However, current workflow inhibits this goal with frequent task switching and unpredictable demands. To assess workflow's cognitive impact, nurses were observed at 2 hospitals with different patient loads and acuity levels. Workflow on a medical/surgical and pediatric oncology unit was observed, recording tasks, tools, collaborators, and locations. Nineteen nurses were observed for a total of 85.2 hours. Tasks were short with a mean duration of 62.4 and 81.6 seconds on the 2 units. More than 50% of the recorded tasks were less than 30 seconds in length. An analysis of task sequence revealed few patterns and little pairwise repetition. Performance on specific tasks differed between the 2 units, but the character of the workflow was highly similar. The nonrepetitive flow and high amount of switching indicate nurses experience a heavy cognitive load with little uninterrupted time. This implies that nurses rarely have the conditions necessary for critical thinking.

Context-sensitive grapheme-phoneme conversion rules impairment in the semantic variant of primary progressive aphasia.

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Joël Macoir

2014-04-01

Results. As shown in Table 1, NG and ND's performance was well preserved in tasks with words and nonwords with n-cGPC rules. However, ND was impaired in all tasks with c-sGPC rules, whilst NG's performance was affected for c-sGPC stimuli only in the rhyming task. Discussion. The processing of regular words and nonwords is assumed to be unimpaired in svPPA since their production do not necessary rely on the lexical-semantic route of reading and spelling. In the present study, this hypothesis was confirmed for n-cGPC rules only. However, both patients presented with difficulty in c-sGPC stimuli. This pattern of performance, never reported before in svPPA, questions the possible role of semantic memory in the reading and spelling of stimuli comprising consistent but contextual GPC rules.

What’s Easier: Doing What You Want, or Being Told What to Do? Cued versus Voluntary Language and Task Switching

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Gollan, Tamar H.; Kleinman, Daniel; Wierenga, Christina E.

2014-01-01

The current study contrasted cued versus voluntary switching to investigate switching efficiency and possible sharing of control mechanisms across linguistic and non-linguistic domains. Bilinguals switched between naming pictures in Spanish versus English or between reading numbers aloud versus adding their digits, either without or with repetition of stimuli, and with fewer requirements as to when and how much they had to switch relative to previous instantiations of voluntary switching. Without repetition (Experiment 1), voluntary responses were faster than cued responses on both stay and switch trials (especially in the non-linguistic switching task), whereas in previous studies the voluntary advantage was restricted to switch-cost reduction. Similarly, when targets were presented repeatedly (Experiment 2), voluntary responses were faster overall for both linguistic and non-linguistic switching, though here the advantage tended to be larger on switch trials. Experiment 3 confirmed the overall voluntary speed advantage for the read-add task in monolinguals, and revealed a reduction in switch costs only for a different non-linguistic task (size-parity judgments). These results reveal greater overall advantages for voluntary over cued switching than previously reported, but also that the precise manifestation of the voluntary advantage can vary with different tasks. In the linguistic domain, lexical inaccessibility introduces some unique control mechanisms, and repetition may magnify cross-domain overlap in control mechanisms. Finally, under some limited conditions, cost-free switches were found in both linguistic and non-linguistic domains; however, suspension of top-down control may be restricted to language or highly automatic tasks. PMID:25313951

Pre-Lexical Disorders in Repetition Conduction Aphasia

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Sidiropoulos, Kyriakos; de Bleser, Ria; Ackermann, Hermann; Preilowski, Bruno

2008-01-01

At the level of clinical speech/language evaluation, the repetition type of conduction aphasia is characterized by repetition difficulties concomitant with reduced short-term memory capacities, in the presence of fluent spontaneous speech as well as unimpaired naming and reading abilities. It is still unsettled which dysfunctions of the…

Evidence for the involvement of a nonlexical route in the repetition of familiar words: A comparison of single and dual route models of auditory repetition.

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Hanley, J Richard; Dell, Gary S; Kay, Janice; Baron, Rachel

2004-03-01

In this paper, we attempt to simulate the picture naming and auditory repetition performance of two patients reported by Hanley, Kay, and Edwards (2002), who were matched for picture naming score but who differed significantly in their ability to repeat familiar words. In Experiment 1, we demonstrate that the model of naming and repetition put forward by Foygel and Dell (2000) is better able to accommodate this pattern of performance than the model put forward by Dell, Schwartz, Martin, Saffran, and Gagnon (1997). Nevertheless, Foygel and Dell's model underpredicted the repetition performance of both patients. In Experiment 2, we attempt to simulate their performance using a new dual route model of repetition in which Foygel and Dell's model is augmented by an additional nonlexical repetition pathway. The new model provided a more accurate fit to the real-word repetition performance of both patients. It is argued that the results provide support for dual route models of auditory repetition.

Freezing during tapping tasks in patients with advanced Parkinson's disease and freezing of gait.

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Delval, Arnaud; Defebvre, Luc; Tard, Céline

2017-01-01

Parkinson's disease patients with freezing of gait also experience sudden motor blocks (freezing) during other repetitive motor tasks. We assessed the proportion of patients with advanced PD and freezing of gait who also displayed segmental "freezing" in tapping tasks. Fifteen Parkinson's disease patients with freezing of gait were assessed. Freezing of gait was evaluated using a standardized gait trajectory with the usual triggers. Patients performed repetitive tapping movements (as described in the MDS-UPDRS task) with the hands or the feet in the presence or absence of a metronome set to 4 Hz. Movements were recorded with a video motion system. The primary endpoint was the occurrence of segmental freezing in these tapping tasks. The secondary endpoints were (i) the relationship between segmental episodic phenomena and FoG severity, and (ii) the reliability of the measurements. For the upper limbs, freezing was observed more frequently with a metronome (21% of trials) than without a metronome (5%). For the lower limbs, the incidence of freezing was higher than for the upper limbs, and was again observed more frequently in the presence of an auditory cue (47%) than in its absence (14%). Although freezing of the lower limbs was easily assessed during an MDS-UPDRS task with a metronome, it was not correlated with the severity of freezing of gait (as evaluated during a standardized gait trajectory). Only this latter was a reliable measurement in patients with advanced Parkinson's disease.

Parental phonological memory contributes to prediction of outcome of late talkers from 20 months to 4 years: a longitudinal study of precursors of specific language impairment

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Bishop Dorothy VM

2012-02-01

Full Text Available Abstract Background Many children who are late talkers go on to develop normal language, but others go on to have longer-term language difficulties. In this study, we considered which factors were predictive of persistent problems in late talkers. Methods Parental report of expressive vocabulary at 18 months of age was used to select 26 late talkers and 70 average talkers, who were assessed for language and cognitive ability at 20 months of age. Follow-up at 4 years of age was carried out for 24 late and 58 average talkers. A psychometric test battery was used to categorize children in terms of language status (unimpaired or impaired and nonverbal ability (normal range or more than 1 SD below average. The vocabulary and non-word repetition skills of the accompanying parent were also assessed. Results Among the late talkers, seven (29% met our criteria for specific language impairment (SLI at 4 years of age, and a further two (8% had low nonverbal ability. In the group of average talkers, eight (14% met the criteria for SLI at 4 years, and five other children (8% had low nonverbal ability. Family history of language problems was slightly better than late-talker status as a predictor of SLI.. The best predictors of SLI at 20 months of age were score on the receptive language scale of the Mullen Scales of Early Learning and the parent's performance on a non-word repetition task. Maternal education was not a significant predictor of outcome. Conclusions In this study, around three-quarters of late talkers did not have any language difficulties at 4 years of age, provided there was no family history of language impairment. A family history of language-literacy problems was found to be a significant predictor for persisting problems. Nevertheless, there are children with SLI for whom prediction is difficult because they did not have early language delay.

Non-invasive mapping of calculation function by repetitive navigated transcranial magnetic stimulation.

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Maurer, Stefanie; Tanigawa, Noriko; Sollmann, Nico; Hauck, Theresa; Ille, Sebastian; Boeckh-Behrens, Tobias; Meyer, Bernhard; Krieg, Sandro M

2016-11-01

Concerning calculation function, studies have already reported on localizing computational function in patients and volunteers by functional magnetic resonance imaging and transcranial magnetic stimulation. However, the development of accurate repetitive navigated TMS (rTMS) with a considerably higher spatial resolution opens a new field in cognitive neuroscience. This study was therefore designed to evaluate the feasibility of rTMS for locating cortical calculation function in healthy volunteers, and to establish this technique for future scientific applications as well as preoperative mapping in brain tumor patients. Twenty healthy subjects underwent rTMS calculation mapping using 5 Hz/10 pulses. Fifty-two previously determined cortical spots of the whole hemispheres were stimulated on both sides. The subjects were instructed to perform the calculation task composed of 80 simple arithmetic operations while rTMS pulses were applied. The highest error rate (80 %) for all errors of all subjects was observed in the right ventral precentral gyrus. Concerning division task, a 45 % error rate was achieved in the left middle frontal gyrus. The subtraction task showed its highest error rate (40 %) in the right angular gyrus (anG). In the addition task a 35 % error rate was observed in the left anterior superior temporal gyrus. Lastly, the multiplication task induced a maximum error rate of 30 % in the left anG. rTMS seems feasible as a way to locate cortical calculation function. Besides language function, the cortical localizations are well in accordance with the current literature for other modalities or lesion studies.

Relationship between the number of repetitions and selected percentages of one repetition maximum in free weight exercises in trained and untrained men.

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Shimano, Tomoko; Kraemer, William J; Spiering, Barry A; Volek, Jeff S; Hatfield, Disa L; Silvestre, Ricardo; Vingren, Jakob L; Fragala, Maren S; Maresh, Carl M; Fleck, Steven J; Newton, Robert U; Spreuwenberg, Luuk P B; Häkkinen, Keijo

2006-11-01

Resistance exercise intensity is commonly prescribed as a percent of 1 repetition maximum (1RM). However, the relationship between percent 1RM and the number of repetitions allowed remains poorly studied, especially using free weight exercises. The purpose of this study was to determine the maximal number of repetitions that trained (T) and untrained (UT) men can perform during free weight exercises at various percentages of 1RM. Eight T and 8 UT men were tested for 1RM strength. Then, subjects performed 1 set to failure at 60, 80, and 90% of 1RM in the back squat, bench press, and arm curl in a randomized, balanced design. There was a significant (p squat than the bench press or arm curl at 60% 1RM for T and UT. At 80 and 90% 1RM, there were significant differences between the back squat and other exercises; however, differences were much less pronounced. No differences in number of repetitions performed at a given exercise intensity were noted between T and UT (except during bench press at 90% 1RM). In conclusion, the number of repetitions performed at a given percent of 1RM is influenced by the amount of muscle mass used during the exercise, as more repetitions can be performed during the back squat than either the bench press or arm curl. Training status of the individual has a minimal impact on the number of repetitions performed at relative exercise intensity.

Evaluating the role of prefrontal and parietal cortices in memory-guided response with repetitive transcranial magnetic stimulation

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Hamidi, Massihullah; Tononi, Giulio; Postle, Bradley R.

2008-01-01

The dorsolateral prefrontal cortex (dlPFC) plays an important role in working memory, including the control of memory-guided response. In this study, with 24 subjects, we used high frequency repetitive transcranial magnetic stimulation (rTMS) to evaluate the role of the dlPFC in memory-guided response to two different types of spatial working memory tasks: one requiring a recognition decision about a probe stimulus (operationalized with a yes/no button press), another requiring direct recall ...

Second Language Word Learning through Repetition and Imitation: Functional Networks as a Function of Learning Phase and Language Distance.

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Ghazi-Saidi, Ladan; Ansaldo, Ana Ines

2017-01-01

pairs. Moreover, higher network integration was observed in the learners with the close language pair, suggesting that repetition effects on network configuration vary as a function of task complexity.

Auditory Verbal Working Memory as a Predictor of Speech Perception in Modulated Maskers in Listeners With Normal Hearing.

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Millman, Rebecca E; Mattys, Sven L

2017-05-24

Background noise can interfere with our ability to understand speech. Working memory capacity (WMC) has been shown to contribute to the perception of speech in modulated noise maskers. WMC has been assessed with a variety of auditory and visual tests, often pertaining to different components of working memory. This study assessed the relationship between speech perception in modulated maskers and components of auditory verbal working memory (AVWM) over a range of signal-to-noise ratios. Speech perception in noise and AVWM were measured in 30 listeners (age range 31-67 years) with normal hearing. AVWM was estimated using forward digit recall, backward digit recall, and nonword repetition. After controlling for the effects of age and average pure-tone hearing threshold, speech perception in modulated maskers was related to individual differences in the phonological component of working memory (as assessed by nonword repetition) but only in the least favorable signal-to-noise ratio. The executive component of working memory (as assessed by backward digit) was not predictive of speech perception in any conditions. AVWM is predictive of the ability to benefit from temporal dips in modulated maskers: Listeners with greater phonological WMC are better able to correctly identify sentences in modulated noise backgrounds.

Inverted U-shaped model: How frequent repetition affects perceived risk

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Xi Lu; Xiaofei Xie; Lu Liu

2015-01-01

We asked how repeated media reports on technological hazards influence an individual's risk perception. We looked for two contradictory effects, an increasing effect of repetition on perceived risk with the first few repetitions and a decreasing effect with later repetitions, leading to the inverted U-shaped pattern. In an experiment, we demonstrated the inverted U-shaped relationship between the repetition and perceived risk in the context of food risk. The finding broaden...

A Comparison between the Occurrence of Pauses, Repetitions and Recasts under Conditions of Face-to-Face and Computer-Mediated Communication: A Preliminary Study

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Cabaroglu, Nese; Basaran, Suleyman; Roberts, Jon

2010-01-01

This study compares pauses, repetitions and recasts in matched task interactions under face-to-face and computer-mediated conditions. Six first-year English undergraduates at a Turkish University took part in Skype-based voice chat with a native speaker and face-to-face with their instructor. Preliminary quantitative analysis of transcripts showed…

Bilingual Phonological Awareness: Multilevel Construct Validation among Spanish-Speaking Kindergarteners in Transitional Bilingual Education Classrooms

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Branum-Martin, Lee; Mehta, Paras D.; Fletcher, Jack M.; Carlson, Coleen D.; Ortiz, Alba; Carlo, Maria; Francis, David J.

2006-01-01

The construct validity of English and Spanish phonological awareness (PA) tasks was examined with a sample of 812 kindergarten children from 71 transitional bilingual education program classrooms located in 3 different types of geographic regions in California and Texas. Tasks of PA, including blending nonwords, segmenting words, and phoneme…

Pathways of the inferior frontal occipital fasciculus in overt speech and reading.

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Rollans, Claire; Cheema, Kulpreet; Georgiou, George K; Cummine, Jacqueline

2017-11-19

In this study, we examined the relationship between tractography-based measures of white matter integrity (ex. fractional anisotropy [FA]) from diffusion tensor imaging (DTI) and five reading-related tasks, including rapid automatized naming (RAN) of letters, digits, and objects, and reading of real words and nonwords. Twenty university students with no reported history of reading difficulties were tested on all five tasks and their performance was correlated with diffusion measures extracted through DTI tractography. A secondary analysis using whole-brain Tract-Based Spatial Statistics (TBSS) was also used to find clusters showing significant negative correlations between reaction time and FA. Results showed a significant relationship between the left inferior fronto-occipital fasciculus FA and performance on the RAN of objects task, as well as a strong relationship to nonword reading, which suggests a role for this tract in slower, non-automatic and/or resource-demanding speech tasks. There were no significant relationships between FA and the faster, more automatic speech tasks (RAN of letters and digits, and real word reading). These findings provide evidence for the role of the inferior fronto-occipital fasciculus in tasks that are highly demanding of orthography-phonology translation (e.g., nonword reading) and semantic processing (e.g., RAN object). This demonstrates the importance of the inferior fronto-occipital fasciculus in basic naming and suggests that this tract may be a sensitive predictor of rapid naming performance within the typical population. We discuss the findings in the context of current models of reading and speech production to further characterize the white matter pathways associated with basic reading processes. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Sex differences in task distribution and task exposures among Danish house painters: an observational study combining questionnaire data with biomechanical measurements.

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Thomas Heilskov-Hansen

Full Text Available OBJECTIVES: Sex differences in occupational biomechanical exposures may be part of the explanation why musculoskeletal complaints and disorders tend to be more common among women than among men. We aimed to determine possible sex differences in task distribution and task-specific postures and movements of the upper extremities among Danish house painters, and to establish sex-specific task exposure matrices. METHODS: To obtain task distributions, we sent out a questionnaire to all members of the Painters' Union in Denmark (N = 9364, of whom 53% responded. Respondents reported their task distributions in a typical week. To obtain task exposures, postures and movements were measured in 25 male and 25 female house painters for one whole working day per person. We used goniometers on the wrists, and inclinometers on the forehead and the upper arms. Participants filled in a logbook allowing task-specific exposures to be identified. Percentiles and % time with non-neutral postures were used to characterise postures. Velocity, range of motion, repetitiveness, and variation were used as measures of movement. Cochran-Mantel-Haenszel statistics and unpaired double-sided t-tests with post-hoc Bonferroni correction were used to evaluate sex differences. RESULTS: Statistically significant (p<0.05 sex differences were revealed in task proportions, but the proportions differed by less than 4%. For task exposures, no statistically significant sex differences were found. CONCLUSIONS: Only minor sex differences were found in task distribution and task exposures regarding postures and movements among Danish house painters. Sex-specific task exposure matrices were established.

Grade Repetition in Queensland State Prep Classes

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Anderson, Robyn

2012-01-01

The current study considers grade repetition rates in the early years of schooling in Queensland state schools with specific focus on the pre-schooling year, Prep. In particular, it provides empirical evidence of grade repetition in Queensland state schools along with groups of students who are more often repeated. At the same time, much of the…

Task switching costs in preschool children and adults.

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Peng, Anna; Kirkham, Natasha Z; Mareschal, Denis

2018-08-01

Past research investigating cognitive flexibility has shown that preschool children make many perseverative errors in tasks that require switching between different sets of rules. However, this inflexibility might not necessarily hold with easier tasks. The current study investigated the developmental differences in cognitive flexibility using a task-switching procedure that compared reaction times and accuracy in 4- and 6-year-olds with those in adults. The experiment involved simple target detection tasks and was intentionally designed in a way that the stimulus and response conflicts were minimal together with a long preparation window. Global mixing costs (performance costs when multiple tasks are relevant in a context), and local switch costs (performance costs due to switching to an alternative task) are typically thought to engage endogenous control processes. If this is the case, we should observe developmental differences with both of these costs. Our results show, however, that when the accuracy was good, there were no age differences in cognitive flexibility (i.e., the ability to manage multiple tasks and to switch between tasks) between children and adults. Even though preschool children had slower reaction times and were less accurate, the mixing and switch costs associated with task switching were not reliably larger for preschool children. Preschool children did, however, show more commission errors and greater response repetition effects than adults, which may reflect differences in inhibitory control. Copyright © 2018 Elsevier Inc. All rights reserved.

RPERT: Repetitive-Projects Evaluation and Review Technique

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Remon Fayek Aziz

2014-03-01

Full Text Available Estimating expected completion probability of any repetitive construction project with a specified/certain duration including repetitive identical activities by using program evaluation and review technique is the most essential part in construction areas since the activities were had optimistic, most likely and pessimistic durations. This paper focuses on the calculation of expected completion probability of any repetitive construction project within a specified/certain duration (contract duration by using Line Of Balance technique (LOB in case of single or multiple number of crews integrated with Program Evaluation and Review Technique (PERT. Repetitive-Projects Evaluation and Review Technique (RPERT, which is a simplified software, will generate the expected project completion probability of a specified/certain duration (contract duration. RPERT software is designed by java programming code system to provide a number of new and unique capabilities, including: (1 Viewing the expected project completion probability according to a set of specified durations per each identical activity (optimistic time, most likely time, and pessimistic time in the analyzed project; (2 Providing seamless integration with available project time calculations. In order to provide the aforementioned capabilities of RPERT, the system is implemented and developed in four main modules: (1 A user interface module; (2 A database module; (3 A running module; and (4 A processing module. At the end, an illustrative example will be presented to demonstrate and verify the applications of proposed software (RPERT, by using probabilistic calculations for repetitive construction projects.

Evidence for repetitive load in the trapezius muscle during a tapping task.

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Tomatis, L; Müller, C; Nakaseko, M; Läubli, T

2012-08-01

Many studies describe the trapezius muscle activation pattern during repetitive key-tapping focusing on continuous activation. The objectives of this study were to determine whether the upper trapezius is phasically active during supported key tapping, whether this activity is cross-correlated with forearm muscle activity, and whether trapezius activity depends on key characteristic. Thirteen subjects (29.7 ± 11.4 years) were tested. Surface EMG of the finger's extensor and flexor and of the trapezius muscles, as well as the key on-off signal was recorded while the subject performed a 2-min session of key tapping at 4 Hz. The linear envelopes obtained were cut into single tapping cycles extending from one onset to the next onset signal and subsequently time-normalized. Effect size between mean range and maximal standard deviation was calculated to determine as to whether a burst of trapezius muscle activation was present. Cross-correlation was used to determine the time-lag of the activity bursts between forearm and trapezius muscles. For each person the mean and standard deviation of the cross-correlations coefficient between forearm muscles and trapezius were determined. Results showed a burst of activation in the trapezius muscle during most of the tapping cycles. The calculated effect size was ≥0.5 in 67% of the cases. Cross-correlation factors between forearm and trapezius muscle activity were between 0.75 and 0.98 for both extensor and flexor muscles. The cross-correlated phasic trapezius activity did not depend on key characteristics. Trapezius muscle was dynamically active during key tapping; its activity was clearly correlated with forearm muscles' activity.

A Model for Evidence Accumulation in the Lexical Decision Task

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Wagenmakers, Eric-Jan; Steyvers, Mark; Raaijmakers, Jeroen G. W.; Shiffrin, Richard M.; van Rijn, Hedderik; Zeelenberg, Rene

2004-01-01

We present a new model for lexical decision, REM-LD, that is based on REM theory (e.g., Shiffrin & Steyvers, 1997). REM-LD uses a principled (i.e., Bayes' rule) decision process that simultaneously considers the diagnosticity of the evidence for the 'WORD' response and the 'NONWORD' response. The model calculates the odds ratio that the presented…

Context influences the motivation for stereotypic and repetitive behaviour in children diagnosed with intellectual disability with and without autism.

Science.gov (United States)

Joosten, Annette V; Bundy, Anita C; Einfeld, Stewart L

2012-05-01

Children are motivated to engage in stereotypic and repetitive behaviours for a number of reasons. Their motivation seems to change according to context, but little empirical evidence supports that observation. Interventions designed to reduce the behaviours may be improved by an increased understanding of the interaction between motivation and context. Using Rasch analysis, we analysed data describing stereotypic behaviours from 279 Revised Motivation Assessment Scales (MAS:R). Data were gathered from two groups of children: Group 1 with intellectual disability (n = 37) and Group 2 with both intellectual disability and autism (n = 37). We examined behaviours in three contexts: free time, transition and while engaged in tasks. MAS:R distinguishes two intrinsic motivators: enhanced sensation and decreased anxiety and three extrinsic motivators: seeking attention or objects or escape. Significant differences in motivators were observed during free time and transition. No one motivator predominated while children were engaged in tasks. For both groups, sensory enhancement was a more likely motivator in free time and anxiety reduction was a more likely motivator during transition. Transition was the context most likely to influence extrinsic motivators, but there were significant differences between the groups. Context influences the motivation for stereotyped and repetitive behaviours. Transition has a particularly powerful effect. © 2012 Blackwell Publishing Ltd.

Post-task Effects on EEG Brain Activity Differ for Various Differential Learning and Contextual Interference Protocols

Directory of Open Access Journals (Sweden)

Diana Henz

2018-01-01

Full Text Available A large body of research has shown superior learning rates in variable practice compared to repetitive practice. More specifically, this has been demonstrated in the contextual interference (CI and in the differential learning (DL approach that are both representatives of variable practice. Behavioral studies have indicate different learning processes in CI and DL. Aim of the present study was to examine immediate post-task effects on electroencephalographic (EEG brain activation patterns after CI and DL protocols that reveal underlying neural processes at the early stage of motor consolidation. Additionally, we tested two DL protocols (gradual DL, chaotic DL to examine the effect of different degrees of stochastic fluctuations within the DL approach with a low degree of fluctuations in gradual DL and a high degree of fluctuations in chaotic DL. Twenty-two subjects performed badminton serves according to three variable practice protocols (CI, gradual DL, chaotic DL, and a repetitive learning protocol in a within-subjects design. Spontaneous EEG activity was measured before, and immediately after each 20-min practice session from 19 electrodes. Results showed distinguishable neural processes after CI, DL, and repetitive learning. Increases in EEG theta and alpha power were obtained in somatosensory regions (electrodes P3, P7, Pz, P4, P8 in both DL conditions compared to CI, and repetitive learning. Increases in theta and alpha activity in motor areas (electrodes C3, Cz, C4 were found after chaotic DL compared to gradual DL, and CI. Anterior areas (electrodes F3, F7, Fz, F4, F8 showed increased activity in the beta and gamma bands after CI. Alpha activity was increased in occipital areas (electrodes O1, O2 after repetitive learning. Post-task EEG brain activation patterns suggest that DL stimulates the somatosensory and motor system, and engages more regions of the cortex than repetitive learning due to a tighter stimulation of the motor and

Repetitive transcranial magnetic stimulation affects behavior by biasing endogenous cortical oscillations

Directory of Open Access Journals (Sweden)

Massihullah Hamidi

2009-06-01

Full Text Available A governing assumption about repetitive transcranial magnetic stimulation (rTMS has been that it interferes with task-related neuronal activity – in effect, by “injecting noise” into the brain – and thereby disrupts behavior. Recent reports of rTMS-produced behavioral enhancement, however, call this assumption into question. We investigated the neurophysiological effects of rTMS delivered during the delay period of a visual working memory task by simultaneously recording brain activity with electroencephalography (EEG. Subjects performed visual working memory for locations or for shapes, and in half the trials a 10-Hz train of rTMS was delivered to the superior parietal lobule or a control brain area. The wide range of individual differences in the effects of rTMS on task accuracy, from improvement to impairment, was predicted by individual differences in the effect of rTMS on power in the alpha-band of the EEG (~ 10 Hz: a decrease in alpha-band power corresponded to improved performance, whereas an increase in alpha-band power corresponded to the opposite. The EEG effect was localized to cortical sources encompassing the frontal eye fields and the intraparietal sulcus, and was specific to task (location, but not object memory and to rTMS target (superior parietal lobule, not control area. Furthermore, for the same task condition, rTMS-induced changes in cross-frequency phase synchrony between alpha- and gamma-band (> 40 Hz oscillations predicted changes in behavior. These results suggest that alpha-band oscillations play an active role cognitive processes and do not simply reflect absence of processing. Furthermore, this study shows that the complex effects of rTMS on behavior can result from biasing endogenous patterns of network-level oscillations.

The activation of visual memory for facial identity is task-dependent: evidence from human electrophysiology.

Science.gov (United States)

Zimmermann, Friederike G S; Eimer, Martin

2014-05-01

The question whether the recognition of individual faces is mandatory or task-dependent is still controversial. We employed the N250r component of the event-related potential as a marker of the activation of representations of facial identity in visual memory, in order to find out whether identity-related information from faces is encoded and maintained even when facial identity is task-irrelevant. Pairs of faces appeared in rapid succession, and the N250r was measured in response to repetitions of the same individual face, as compared to presentations of two different faces. In Experiment 1, an N250r was present in an identity matching task where identity information was relevant, but not when participants had to detect infrequent targets (inverted faces), and facial identity was task-irrelevant. This was the case not only for unfamiliar faces, but also for famous faces, suggesting that even famous face recognition is not as automatic as is often assumed. In Experiment 2, an N250r was triggered by repetitions of non-famous faces in a task where participants had to match the view of each face pair, and facial identity had to be ignored. This shows that when facial features have to be maintained in visual memory for a subsequent comparison, identity-related information is retained as well, even when it is irrelevant. Our results suggest that individual face recognition is neither fully mandatory nor completely task-dependent. Facial identity is encoded and maintained in tasks that involve visual memory for individual faces, regardless of the to-be-remembered feature. In tasks without this memory component, irrelevant visual identity information can be completely ignored. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Verification Method of Inter-Task Cooperation in Embedded Real-time Systems and its Evaluation

Science.gov (United States)

Yoshida, Toshio

In software development process of embedded real-time systems, the design of the task cooperation process is very important. The cooperating process of such tasks is specified by task cooperation patterns. Adoption of unsuitable task cooperation patterns has fatal influence on system performance, quality, and extendibility. In order to prevent repetitive work caused by the shortage of task cooperation performance, it is necessary to verify task cooperation patterns in an early software development stage. However, it is very difficult to verify task cooperation patterns in an early software developing stage where task program codes are not completed yet. Therefore, we propose a verification method using task skeleton program codes and a real-time kernel that has a function of recording all events during software execution such as system calls issued by task program codes, external interrupts, and timer interrupt. In order to evaluate the proposed verification method, we applied it to the software development process of a mechatronics control system.

Bursts of occipital theta and alpha amplitude preceding alternation and repetition trials in a task-switching experiment

NARCIS (Netherlands)

Gladwin, T.E.; De Jong, Ritske

The instantaneous amplitude of the theta and alpha bands of the electroencephalogram (EEG) was studied during preparation periods in a task-switching experiment. Subjects had to switch between tasks in which they were to respond to either the visual or the auditory component of the stimulus. 11-13

Repetitive exposure: Brain and reflex measures of emotion and attention

Science.gov (United States)

Ferrari, Vera; Bradley, Margaret M.; Codispoti, Maurizio; Lang, Peter J.

2010-01-01

Effects of massed repetition on the modulation of the late positive potential elicited during affective picture viewing were investigated in two experiments. Despite a difference in the number of repetitions across studies (from 5 to 30), results were quite similar: the late positive potential continued to be enhanced when viewing emotional, compared to neutral, pictures. On the other hand, massed repetition did prompt a reduction in the late positive potential that was most pronounced for emotional pictures. Startle probe P3 amplitude generally increased with repetition, suggesting diminished attention allocation to repeated pictures. The blink reflex, however, continued to be modulated by hedonic valence, despite massive massed repetition. Taken together, the data suggest that the amplitude of the late positive potential during picture viewing reflects both motivational significance and attention allocation. PMID:20701711

Assessing the influence of a passive, upper extremity exoskeletal vest for tasks requiring arm elevation: Part I - "Expected" effects on discomfort, shoulder muscle activity, and work task performance.

Science.gov (United States)

Kim, Sunwook; Nussbaum, Maury A; Mokhlespour Esfahani, Mohammad Iman; Alemi, Mohammad Mehdi; Alabdulkarim, Saad; Rashedi, Ehsan

2018-03-07

Use of exoskeletal vests (designed to support overhead work) can be an effective intervention approach for tasks involving arm elevation, yet little is known on the potential beneficial impacts of their use on physical demands and task performance. This laboratory study (n = 12) evaluated the effects of a prototype exoskeletal vest during simulated repetitive overhead drilling and light assembly tasks. Anticipated or expected benefits were assessed, in terms of perceived discomfort, shoulder muscle activity, and task performance. Using the exoskeletal vest did not substantially influence perceived discomfort, but did decrease normalized shoulder muscle activity levels (e.g., ≤ 45% reduction in peak activity). Drilling task completion time decreased by nearly 20% with the vest, but the number of errors increased. Overall, exoskeletal vest use has the potential to be a new intervention for work requiring arm elevation; however, additional investigations are needed regarding potential unexpected or adverse influences (see Part II). Copyright © 2018 Elsevier Ltd. All rights reserved.

Is perfectionism associated with academic burnout through repetitive negative thinking?

Science.gov (United States)

Garratt-Reed, David; Howell, Joel; Hayes, Lana; Boyes, Mark

2018-01-01

Academic burnout is prevalent among university students, although understanding of what predicts burnout is limited. This study aimed to test the direct and indirect relationship between two dimensions of perfectionism (Perfectionistic Concerns and Perfectionistic Strivings) and the three elements of Academic Burnout (Exhaustion, Inadequacy, and Cynicism) through Repetitive Negative Thinking. In a cross-sectional survey, undergraduate students ( n  = 126, M age = 23.64, 79% female) completed well-validated measures of Perfectionism, Repetitive Negative Thinking, and Academic Burnout. Perfectionistic Concerns was directly associated with all elements of burnout, as well as indirectly associated with Exhaustion and Cynicism via Repetitive Negative Thinking. Perfectionistic Strivings was directly associated with less Inadequacy and Cynicism; however, there were no indirect associations between Perfectionistic Strivings and Academic Burnout operating through Repetitive Negative Thinking. Repetitive Negative Thinking was also directly related to more burnout Exhaustion and Inadequacy, but not Cynicism. It is concluded that future research should investigate whether interventions targeting Perfectionistic Concerns and Repetitive Negative Thinking can reduce Academic Burnout in university students.

Categorization difficulty modulates the mediated route for response selection in task switching.

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Schneider, Darryl W

2017-12-22

Conflict during response selection in task switching is indicated by the response congruency effect: worse performance for incongruent targets (requiring different responses across tasks) than for congruent targets (requiring the same response). The effect can be explained by dual-task processing in a mediated route for response selection, whereby targets are categorized with respect to both tasks. In the present study, the author tested predictions for the modulation of response congruency effects by categorization difficulty derived from a relative-speed-of-processing hypothesis. Categorization difficulty was manipulated for the relevant and irrelevant task dimensions in a novel spatial task-switching paradigm that involved judging the locations of target dots in a grid, without repetition of dot configurations. Response congruency effects were observed and they varied systematically with categorization difficulty (e.g., being larger when irrelevant categorization was easy than when it was hard). These results are consistent with the relative-speed-of-processing hypothesis and suggest that task-switching models that implement variations of the mediated route for response selection need to address the time course of categorization.

Repetition code of 15 qubits

Science.gov (United States)

Wootton, James R.; Loss, Daniel

2018-05-01

The repetition code is an important primitive for the techniques of quantum error correction. Here we implement repetition codes of at most 15 qubits on the 16 qubit ibmqx3 device. Each experiment is run for a single round of syndrome measurements, achieved using the standard quantum technique of using ancilla qubits and controlled operations. The size of the final syndrome is small enough to allow for lookup table decoding using experimentally obtained data. The results show strong evidence that the logical error rate decays exponentially with code distance, as is expected and required for the development of fault-tolerant quantum computers. The results also give insight into the nature of noise in the device.

Word Recognition Processing Efficiency as a Component of Second Language Listening

Science.gov (United States)

Joyce, Paul

2013-01-01

This study investigated the application of the speeded lexical decision task to L2 aural processing efficiency. One-hundred and twenty Japanese university students completed an aural word/nonword task. When the variation of lexical decision time (CV) was correlated with reaction time (RT), the results suggested that the single-word recognition…

Nanosecond radar system based on repetitive pulsed relativistic BWO

International Nuclear Information System (INIS)

Bunkin, B.V.; Gaponov-Grekhov, A.V.; Eltchaninov, A.S.; Zagulov, F.Ya.; Korovin, S.D.; Mesyats, G.A.; Osipov, M.L.; Otlivantchik, E.A.; Petelin, M.I.; Prokhorov, A.M.

1993-01-01

The paper presents the results of studies of a nanosecond radar system based on repetitive pulsed relativistic BWO. A pulsed power repetitive accelerator producing electron beams of electron energy 500-700 keV and current 5 kA in pulses of duraction 10 ns with a repetition rate of 100 pps is described. The results of experiments with a high-voltage gas-filled spark gap and a cold-cathode vacuum diode under the conditions of high repetition rates are given. Also presented are the results of studies of a relativistic BWO operating with a wavelength of 3 cm. It is shown that for a high-current beam electron energy of 500-700 keV, the BWO efficiency can reach 35%, the microwave power being 10 9 W. A superconducting solenoid creating a magnetic field of 30 kOe was used for the formation and transportation of the high-current electron beam. In conclusion, the outcome of tests of a nanosecond radar station based on a pulsed power repetitive accelerator and a relativistic BWO is reported

Dual Arm Work Package performance estimates and telerobot task network simulation

International Nuclear Information System (INIS)

Draper, J.V.

1997-01-01

This paper describes the methodology and results of a network simulation study of the Dual Arm Work Package (DAWP), to be employed for dismantling the Argonne National Laboratory CP-5 reactor. The development of the simulation model was based upon the results of a task analysis for the same system. This study was performed by the Oak Ridge National Laboratory (ORNL), in the Robotics and Process Systems Division. Funding was provided the US Department of Energy's Office of Technology Development, Robotics Technology Development Program (RTDP). The RTDP is developing methods of computer simulation to estimate telerobotic system performance. Data were collected to provide point estimates to be used in a task network simulation model. Three skilled operators performed six repetitions of a pipe cutting task representative of typical teleoperation cutting operations

Writing disorders in Italian aphasic patients. A multiple single-case study of dysgraphia in a language with shallow orthography.

Science.gov (United States)

Luzzatti, C; Laiacona, M; Allamano, N; De Tanti, A; Inzaghi, M G

1998-09-01

We report results of a writing task given to 53 mildly to moderately aphasic Italian subjects. The task was designed to test the writing performance along the subword-level routine for the spelling of regular words and non-words, and along the lexical routine for the spelling of irregular words. The aim of the study was to identify the incidence of different dysgraphic subtypes in Italian, a language that is considered to have shallow orthography. Its spelling, however, is not completely free of ambiguity. A five-part writing task was used: (i) words with regular one-sound-to-one-grapheme conversion; (ii) words with regular syllabic conversion; (iii) words with ambiguous transcription; (iv) loan-words; and (v) non-words. For regular words, the effects of word length and word frequency, and of the variables determining the complexity of the acoustic-to-phonological conversion (continuant versus plosive phones; consonant-vowel sequence versus doubled consonants or consonant clusters) were also considered. Patients' performances were classified according to the presence of a dissociation between (i) regular words and non-words, (ii) regular words and words with unpredictable spellings, and (iii) one-to-one and syllabic conversions. The 53 aphasic patients span the whole spectrum of dysgraphic taxonomy. Thirty-nine patients, in particular, manifested a dissociated pattern of performance. Eighteen patients showed a prevalent surface dysgraphic pattern and seven a phonological one, while 11 patients showed a mixed pattern (i.e. a better performance for regular words than for ambiguous words or regular non-words). Three patients showed a specific deficit for regular syllabic conversion rules only. A high rate of 'mixed dysgraphia' suggests either a mutual interaction of the two impaired routines when regular words are written, or two separate functional lesions: one at the level of the auditory-to-phonological conversion procedure, the other at the level of the

Maturation of Rapid Auditory Temporal Processing and Subsequent Nonword Repetition Performance in Children

Science.gov (United States)

Fox, Allison M.; Reid, Corinne L.; Anderson, Mike; Richardson, Cassandra; Bishop, Dorothy V. M.

2012-01-01

According to the rapid auditory processing theory, the ability to parse incoming auditory information underpins learning of oral and written language. There is wide variation in this low-level perceptual ability, which appears to follow a protracted developmental course. We studied the development of rapid auditory processing using event-related…

Presentation-Practice-Production and Task-Based Learning in the Light of Second Language Learning Theories.

Science.gov (United States)

Ritchie, Graeme

2003-01-01

Features of presentation-practice-production (PPP) and task-based learning (TBL) models for language teaching are discussed with reference to language learning theories. Pre-selection of target structures, use of controlled repetition, and explicit grammar instruction in a PPP lesson are given. Suggests TBL approaches afford greater learning…

Introducing IoT and Wearable Technologies into Task-Based Language Learning for Young Children

Science.gov (United States)

de la Guia, Elena; Camacho, Vincent Lopez; Orozco-Barbosa, Luis; Brea Lujan, Victor M.; Penichet, Victor M. R.; Perez, Maria Lozano

2016-01-01

In the last few years, in an attempt to further motivate students to learn a foreign language, there has been an increasing interest in task-based teaching techniques, which emphasize communication and the practical use of language, thus moving away from the repetitive grammar-translation methods. Within this approach, the significance of…

Transgenerational effects of environmental enrichment on repetitive motor behavior development.

Science.gov (United States)

Bechard, Allison R; Lewis, Mark H

2016-07-01

The favorable consequences of environmental enrichment (EE) on brain and behavior development are well documented. Much less is known, however, about transgenerational benefits of EE on non-enriched offspring. We explored whether transgenerational effects of EE might extend to the development of repetitive motor behaviors in deer mice. Repetitive motor behaviors are invariant patterns of movement that, across species, can be reduced by EE. We found that EE not only attenuated the development of repetitive behavior in dams, but also in their non-enriched offspring. Moreover, maternal behavior did not seem to mediate the transgenerational effect we found, although repetitive behavior was affected by reproductive experience. These data support a beneficial transgenerational effect of EE on repetitive behavior development and suggest a novel benefit of reproductive experience. Copyright © 2016 Elsevier B.V. All rights reserved.

Electrical strength of vacuum gap at repetitive breakdown

International Nuclear Information System (INIS)

Dubinin, N.P.; Chistyakov, N.P.

1983-01-01

The investigation of repetitive pulse breakdown of vacuum space, which electrodes have been subjected to various treatment in vacuum and inert gas, is carried out. In case of electrode warm-up in vacuum up to 400 deg C as well as electronic heating up to 900 deg C the voltage in case of repetitive breakdown hasncreased approximately twice and in case of a through treatment, which is accomplished by a high-current glow discharge in inert gas, the maximum high voltage in case of the first breakdown at repetitive breakdown has decreased by 30...40%, remaining 2-3 times higher than in the first case

Two discharge modes of a repetitive nanosecond pulsed helium glow discharge under sub-atmospheric pressure in the repetition frequency range of 20 to 600 kHz

Science.gov (United States)

Kikuchi, Yusuke; Maegawa, Takuya; Otsubo, Akira; Nishimura, Yoshimi; Nagata, Masayoshi; Yatsuzuka, Mitsuyasu

2018-05-01

Two discharge modes, α and γ, of a repetitive nanosecond pulsed helium glow discharge at a gas pressure of 10 kPa in the repetition frequency range from 20 to 600 kHz are reported for the first time. The pulsed glow discharge is produced in a pair of parallel plate metal electrodes without insertion of dielectrics. The α mode discharge is volumetrically produced in the electrode gap at a low-repetition frequency, whereas the γ mode discharge is localized at the cathode surface at a high-repetition frequency. At high-repetition frequency, the time interval between voltage pulses is shorter than the lifetime of the afterglow produced by the preceding discharge. Then, the γ mode discharge is maintained by a large number of secondary electrons emitted from the cathode exposed to high-density ions and metastable helium atoms in the afterglow. In the α mode discharge with a low-repetition frequency operation, primary electrons due to gas ionization dominate the ionization process. Thus, a large discharge voltage is needed for the excitation of the α mode discharge. It is established that the bifurcation of α-γ discharge mode, accompanied by a decrease in the discharge voltage, occurs at the high-repetition frequency of ∼120 kHz.

Recency, repetition, and the multidimensional basis of recognition memory.

Science.gov (United States)

Buchsbaum, Bradley R; Lemire-Rodger, Sabrina; Bondad, Ashley; Chepesiuk, Alexander

2015-02-25

Recency and repetition are two factors that have large effects on human memory performance. One way of viewing the beneficial impact of these variables on recognition memory is to assume that both factors modulate a unidimensional memory trace strength. Although previous functional neuroimaging studies have indicated that recency and repetition may modulate similar brain structures, particularly in the region of the inferior parietal cortex, there is extensive behavioral evidence that human subjects can make independent and accurate recognition memory judgments about both an item's recency and its frequency. In the present study, we used fMRI to examine patterns of brain activity during recognition memory for auditory-verbal stimuli that were parametrically and orthogonally manipulated in terms of recency and number of repetitions. We found in a continuous recognition paradigm that the lateral inferior parietal cortex, a region that has previously been associated with recollective forms of memory, is highly sensitive to recency but not repetition. In a multivariate analysis of whole-brain activation patterns, we found orthogonal components that dissociated recency and repetition variables, indicating largely independent neural bases underlying these two factors. The results demonstrate that although both recency and repetition dramatically improve recognition memory performance, the neural bases for this improvement are dissociable, and thus are difficult to explain in terms of access to a unitary memory trace. Copyright © 2015 the authors 0270-6474/15/353544-11$15.00/0.

Repetition of Attempted Suicide Among Immigrants in Europe

Science.gov (United States)

Lipsicas, Cendrine Bursztein; Mäkinen, Ilkka Henrik; Wasserman, Danuta; Apter, Alan; Kerkhof, Ad; Michel, Konrad; Renberg, Ellinor Salander; van Heeringen, Kees; Värnik, Airi; Schmidtke, Armin

2014-01-01

Objectives To compare frequencies of suicide attempt repetition in immigrants and local European populations, and the timing of repetition in these groups. Method: Data from 7 European countries, comprising 10 574 local and 3032 immigrant subjects, were taken from the World Health Organization European Multicentre Study on Suicidal Behaviour and the ensuing Monitoring Suicidal Behaviour in Europe (commonly referred to as MONSUE) project. The relation between immigrant status and repetition of suicide attempt within 12-months following first registered attempt was analyzed with binary logistic regression, controlling for sex, age, and method of attempt. Timing of repetition was controlled for sex, age, and the recommended type of aftercare. Results: Lower odds of repeating a suicide attempt were found in Eastern European (OR 0.50; 95% CI 0.41 to 0.61, P Europe stands in contrast to their markedly higher tendency to attempt suicide in general, possibly pointing to situational stress factors related to their suicidal crisis that are less persistent over time. Our findings also raise the possibility that suicide attempters and repeaters constitute only partially overlapping populations. PMID:25565687

The development of interactive multimedia based on auditory, intellectually, repetition in repetition algorithm learning to increase learning outcome

Science.gov (United States)

Munir; Sutarno, H.; Aisyah, N. S.

2018-05-01

This research aims to find out how the development of interactive multimedia based on auditory, intellectually, and repetition can improve student learning outcomes. This interactive multimedia is developed through 5 stages. Analysis stages include the study of literature, questionnaire, interviews and observations. The design phase is done by the database design, flowchart, storyboards and repetition algorithm material while the development phase is done by the creation of web-based framework. Presentation material is adapted to the model of learning such as auditory, intellectually, repetition. Auditory points are obtained by recording the narrative material that presented by a variety of intellectual points. Multimedia as a product is validated by material and media experts. Implementation phase conducted on grade XI-TKJ2 SMKN 1 Garut. Based on index’s gain, an increasing of student learning outcomes in this study is 0.46 which is fair due to interest of student in using interactive multimedia. While the multimedia assessment earned 84.36% which is categorized as very well.

One set of pliers for more tasks in installation work: The effects on (dis)comfort and productivity

NARCIS (Netherlands)

Groenesteijn, L.; Eikhout, S.M.; Vink, P.

2004-01-01

In installation work, the physical workload is high. Awkward postures, heavy lifting and repetitive movements are often seen. To improve aspects of the work situation, frequently used pliers were redesigned to make them suitable for more cutting tasks. In this study these multitask pliers are

Repetition suppression and repetition enhancement underlie auditory memory-trace formation in the human brain: an MEG study.

Science.gov (United States)

Recasens, Marc; Leung, Sumie; Grimm, Sabine; Nowak, Rafal; Escera, Carles

2015-03-01

The formation of echoic memory traces has traditionally been inferred from the enhanced responses to its deviations. The mismatch negativity (MMN), an auditory event-related potential (ERP) elicited between 100 and 250ms after sound deviation is an indirect index of regularity encoding that reflects a memory-based comparison process. Recently, repetition positivity (RP) has been described as a candidate ERP correlate of direct memory trace formation. RP consists of repetition suppression and enhancement effects occurring in different auditory components between 50 and 250ms after sound onset. However, the neuronal generators engaged in the encoding of repeated stimulus features have received little interest. This study intends to investigate the neuronal sources underlying the formation and strengthening of new memory traces by employing a roving-standard paradigm, where trains of different frequencies and different lengths are presented randomly. Source generators of repetition enhanced (RE) and suppressed (RS) activity were modeled using magnetoencephalography (MEG) in healthy subjects. Our results show that, in line with RP findings, N1m (~95-150ms) activity is suppressed with stimulus repetition. In addition, we observed the emergence of a sustained field (~230-270ms) that showed RE. Source analysis revealed neuronal generators of RS and RE located in both auditory and non-auditory areas, like the medial parietal cortex and frontal areas. The different timing and location of neural generators involved in RS and RE points to the existence of functionally separated mechanisms devoted to acoustic memory-trace formation in different auditory processing stages of the human brain. Copyright © 2014 Elsevier Inc. All rights reserved.

Frequency Adaptive Repetitive Control of Grid-Tied Three-Phase PV Inverters

DEFF Research Database (Denmark)

Zhou, Keliang; Yang, Yongheng; Blaabjerg, Frede

2016-01-01

Repetitive control offers an accurate current control scheme for grid-tied converters to feed high quality sinusoidal current into the grid. However, with grid frequency being treated as a constant value, conventional repetitive controller fail to produce high quality feeding current in the prese......Repetitive control offers an accurate current control scheme for grid-tied converters to feed high quality sinusoidal current into the grid. However, with grid frequency being treated as a constant value, conventional repetitive controller fail to produce high quality feeding current...

Where perception meets memory: a review of repetition priming in visual search tasks.

Science.gov (United States)

Kristjánsson, Arni; Campana, Gianluca

2010-01-01

What we have recently seen and attended to strongly influences how we subsequently allocate visual attention. A clear example is how repeated presentation of an object's features or location in visual search tasks facilitates subsequent detection or identification of that item, a phenomenon known as priming. Here, we review a large body of results from priming studies that suggest that a short-term implicit memory system guides our attention to recently viewed items. The nature of this memory system and the processing level at which visual priming occurs are still debated. Priming might be due to activity modulations of low-level areas coding simple stimulus characteristics or to higher level episodic memory representations of whole objects or visual scenes. Indeed, recent evidence indicates that only minor changes to the stimuli used in priming studies may alter the processing level at which priming occurs. We also review recent behavioral, neuropsychological, and neurophysiological evidence that indicates that the priming patterns are reflected in activity modulations at multiple sites along the visual pathways. We furthermore suggest that studies of priming in visual search may potentially shed important light on the nature of cortical visual representations. Our conclusion is that priming occurs at many different levels of the perceptual hierarchy, reflecting activity modulations ranging from lower to higher levels, depending on the stimulus, task, and context-in fact, the neural loci that are involved in the analysis of the stimuli for which priming effects are seen.

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients

OpenAIRE

Hesse, Stefan; Waldner, Andreas; Tomelleri, Christopher

2010-01-01

Abstract Background Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation pat...

Generation of µW level plateau harmonics at high repetition rate.

Science.gov (United States)

Hädrich, S; Krebs, M; Rothhardt, J; Carstens, H; Demmler, S; Limpert, J; Tünnermann, A

2011-09-26

The process of high harmonic generation allows for coherent transfer of infrared laser light to the extreme ultraviolet spectral range opening a variety of applications. The low conversion efficiency of this process calls for optimization or higher repetition rate intense ultrashort pulse lasers. Here we present state-of-the-art fiber laser systems for the generation of high harmonics up to 1 MHz repetition rate. We perform measurements of the average power with a calibrated spectrometer and achieved µW harmonics between 45 nm and 61 nm (H23-H17) at a repetition rate of 50 kHz. Additionally, we show the potential for few-cycle pulses at high average power and repetition rate that may enable water-window harmonics at unprecedented repetition rate. © 2011 Optical Society of America

The effect of single-task and dual-task balance exercise programs on balance performance in adults with osteoporosis: a randomized controlled preliminary trial.

Science.gov (United States)

Konak, H E; Kibar, S; Ergin, E S

2016-11-01

Osteoporosis is a serious disease characterized by muscle weakness in the lower extremities, shortened length of trunk, and increased dorsal kyphosis leading to poor balance performance. Although balance impairment increases in adults with osteoporosis, falls and fall-related injuries have been shown to occur mainly during the dual-task performance. Several studies have shown that dual-task performance was improved with specific repetitive dual-task exercises. The aims of this study were to compare the effect of single- and dual-task balance exercise programs on static balance, dynamic balance, and activity-specific balance confidence in adults with osteoporosis and to assess the effectiveness of dual-task balance training on gait speed under dual-task conditions. Older adults (N = 42) (age range, 45-88 years) with osteoporosis were randomly assigned into two groups. Single-task balance training group was given single-task balance exercises for 4 weeks, whereas dual-task balance training group received dual-task balance exercises. Participants received 45-min individualized training session, three times a week. Static balance was evaluated by one-leg stance (OLS) and a kinesthetic ability trainer (KAT) device. Dynamic balance was measured by the Berg Balance Scale (BBS), Time Up and Go (TUG) test, and gait speed. Self-confidence was assessed with the Activities-specific Balance Confidence (ABC-6) scale. Assessments were performed at baseline and after the 4-week program. At the end of the treatment periods, KAT score, BBS score, time in OLS and TUG, gait speeds under single- and dual-task conditions, and ABC-6 scale scores improved significantly in all patients (p gait speeds under single- and dual-task conditions showed significantly greater improvement in the dual-task balance training group than in the single-task balance training group (p gait speeds showed greater improvement following the application of a specific type of dual-task exercise programs

Gender effects on phonological processing and reading development in Northern Sotho children learning to read in English: A case study of Grade 3 learners

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Carien Wilsenach

2018-01-01

Full Text Available Gender differences in reading development are a global phenomenon, with girls typically performing better than boys. Some studies have reported gender differences favouring girls in reading comprehension in South Africa, but little systematic evidence exists about gender differences in the cognitive-linguistic abilities that underlie reading development. This study investigated the effect of gender on phonological processing and reading development in Northern Sotho–English bilingual children. Grade 3 learners who received their literacy instruction in English were tested on various phonological processing and reading measures. Phonological awareness was assessed using phoneme isolation and elision tasks. Phonological working memory was assessed using memory for digits and non-word repetition tests while rapid automatised naming was tested using rapid letter, rapid digit, rapid object and rapid colour naming tasks. Reading achievement was assessed with various word reading tasks and with a fluent reading task. A multivariate analysis of variance revealed that gender had a significant effect on the phonological processing and reading abilities of Northern Sotho– English bilingual children. Girls performed significantly better than boys on all the reading measures, as well as on some aspects of phonological processing. The findings provide behavioural evidence in support of biological theories of gender differences, in that girls seemed to have developed some of the cognitive-linguistic skills associated with reading before boys. The girls also coped better with tasks that required increased cognitive processing. This study suggests that sex differences in reading development cannot be ignored in South Africa and need to be addressed in future curriculum development.

A longitudinal investigation of perfectionism and repetitive negative thinking in perinatal depression.

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Egan, Sarah J; Kane, Robert T; Winton, Karen; Eliot, Catherine; McEvoy, Peter M

2017-10-01

Repetitive negative thinking and perfectionism have both been proposed as processes that are related to depressive symptoms. The purpose of this study was to investigate concurrent and prospective relationships between antenatal and postnatal depression, perfectionism, and repetitive negative thinking. A longitudinal design was used and 71 women were followed from their third trimester of pregnancy to six weeks post birth. A structural equation model was tested with antenatal perfectionism predicting antenatal repetitive negative thinking, perfectionism predicting postnatal depression, and antenatal repetitive negative thinking predicting antenatal and postnatal depression. The final model provided an adequate fit to the data but the pathway from antenatal repetitive negative thinking to postnatal depression was not significant. The findings provide support for the role of perfectionism and repetitive negative thinking in the onset and maintenance of perinatal symptoms of depression. It is suggested that future research investigates the efficacy of targeting repetitive negative thinking and perfectionism in pregnancy to examine if this can reduce perinatal depression. Copyright © 2017. Published by Elsevier Ltd.

Concreteness of Positive, Negative, and Neutral Repetitive Thinking About the Future

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Behar, Evelyn; McGowan, Sarah Kate; McLaughlin, Katie A.; Borkovec, T.D.; Goldwin, Michelle; Bjorkquist, Olivia

2014-01-01

Consistent with assertions that the adaptiveness of repetitive thinking is influenced by both its valence and style, Stöber (e.g., Stöber & Borkovec, 2002) has argued that worry is characterized by a reduced concreteness of thought content and that the resulting abstractness contributes to its inhibition of some aspects of anxious responding. However, extant research does not provide a direct test of Stöber’s reduced concreteness theory of worry. We sought to test Stöber’s theory and to examine the adaptiveness of repetitive worrisome thinking by randomly assigning 108 participants to engage in five consecutive periods of repetitive thinking about positively, negatively, or neutrally valenced potential future events. Results based on coding of thought data indicated that (a) repetitive thinking became increasingly less concrete as periods progressed; (b) contrary to Stöber’s theory, both negative and positive repetitive future thinking were more concrete than neutral repetitive future thinking (and did not differ from each other); and (c) abstractness of thought during negative repetitive future thinking was associated with reduced reports of imagery-based activity. Results based on self-reported affect indicated that negatively valenced repetitive future thinking was uniquely associated with initial decreases in anxious affect, followed by increased anxious affect that coincided with increased imagery-based activity. This suggests that worry is associated with a sequential mitigation of anxious meaning followed by a strengthening of anxious meaning over time. Theoretical and clinical implications of these findings are discussed. PMID:22440067

Effects of repetition and temperature on Contingent Electrical Stimulation

DEFF Research Database (Denmark)

Castrillon, Eduardo E.; Zhou, Xinwen; Svensson, Peter

) activity associated with bruxism. Repetition of the electrical stimulus and skin surface temperature (ST) may affect the perception of CES and possibly also the inhibitory EMG effects.Objectives: To determine the effects of stimulus repetition and skin ST on the perception of CES.  Methods: Healthy...

Post-exercise cortical depression following repetitive passive finger movement.

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Otsuka, Ryohei; Sasaki, Ryoki; Tsuiki, Shota; Kojima, Sho; Onishi, Hideaki

2017-08-24

This study aimed to clarify the influence of range of repetitive passive finger movement on corticospinal excitability. Thirteen healthy subjects participated in this study. Passive index finger adduction-abduction movements were performed from 15° abduction to 15° adduction, 15° abduction to 0°, 0° to 15° adduction, and 15° adduction to 30° adduction, each at 15°/s for 10min on separate days. Motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation and M- and F-waves were measured before and after each repetitive passive index finger movement protocol to evaluate changes in corticospinal excitability. MEP amplitude significantly decreased after all passive movements, while F-wave amplitude, F-wave persistence, and M-wave amplitude remained stable. These results suggest that cortical excitability decreases after repetitive passive movement. However, the range of repetitive passive movement does not markedly influence the magnitude of cortical depression. Copyright © 2017 Elsevier B.V. All rights reserved.

Pulse repetition rate multiplication by Talbot effect in a coaxial fiber

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Dhingra, Nikhil; Saxena, Geetika Jain; Anand, Jyoti; Sharma, Enakshi K.

2018-03-01

We use a coaxial fiber, which is a cylindrical coupled waveguide structure consisting of two concentric cores, the inner rod and an outer ring core as a first order dispersive media to achieve temporal Talbot effect for pulse repetition rate multiplication (PRRM) in high bit rate optical fiber communication. It is observed that for an input Gaussian pulse train with pulse width, 2τ0=1ps at a repetition rate of 40 Gbps (repetition period, T=25ps), an output repetition rate of 640 Gbps can be achieved without significant distortion at a length of 40.92 m.

Properties of water surface discharge at different pulse repetition rates

International Nuclear Information System (INIS)

Ruma,; Yoshihara, K.; Hosseini, S. H. R.; Sakugawa, T.; Akiyama, H.; Akiyama, M.; Lukeš, P.

2014-01-01

The properties of water surface discharge plasma for variety of pulse repetition rates are investigated. A magnetic pulse compression (MPC) pulsed power modulator able to deliver pulse repetition rates up to 1000 Hz, with 0.5 J per pulse energy output at 25 kV, was used as the pulsed power source. Positive pulse with a point-to-plane electrode configuration was used for the experiments. The concentration and production yield of hydrogen peroxide (H 2 O 2 ) were quantitatively measured and orange II organic dye was treated, to evaluate the chemical properties of the discharge reactor. Experimental results show that the physical and chemical properties of water surface discharge are not influenced by pulse repetition rate, very different from those observed for under water discharge. The production yield of H 2 O 2 and degradation rate per pulse of the dye did not significantly vary at different pulse repetition rates under a constant discharge mode on water surface. In addition, the solution temperature, pH, and conductivity for both water surface and underwater discharge reactors were measured to compare their plasma properties for different pulse repetition rates. The results confirm that surface discharge can be employed at high pulse repetition rates as a reliable and advantageous method for industrial and environmental decontamination applications.

Word Recognition during Reading: The Interaction between Lexical Repetition and Frequency

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Lowder, Matthew W.; Choi, Wonil; Gordon, Peter C.

2013-01-01

Memory studies utilizing long-term repetition priming have generally demonstrated that priming is greater for low-frequency words than for high-frequency words and that this effect persists if words intervene between the prime and the target. In contrast, word-recognition studies utilizing masked short-term repetition priming typically show that the magnitude of repetition priming does not differ as a function of word frequency and does not persist across intervening words. We conducted an eye-tracking while reading experiment to determine which of these patterns more closely resembles the relationship between frequency and repetition during the natural reading of a text. Frequency was manipulated using proper names that were high-frequency (e.g., Stephen) or low-frequency (e.g., Dominic). The critical name was later repeated in the sentence, or a new name was introduced. First-pass reading times and skipping rates on the critical name revealed robust repetition-by-frequency interactions such that the magnitude of the repetition-priming effect was greater for low-frequency names than for high-frequency names. In contrast, measures of later processing showed effects of repetition that did not depend on lexical frequency. These results are interpreted within a framework that conceptualizes eye-movement control as being influenced in different ways by lexical- and discourse-level factors. PMID:23283808

Evidence-Based Behavioral Interventions for Repetitive Behaviors in Autism

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Boyd, Brian A.; McDonough, Stephen G.; Bodfish, James W.

2012-01-01

Restricted and repetitive behaviors (RRBs) are a core symptom of autism spectrum disorders (ASD). There has been an increased research emphasis on repetitive behaviors; however, this research primarily has focused on phenomenology and mechanisms. Thus, the knowledge base on interventions is lagging behind other areas of research. The literature…

Repetitive sequences: the hidden diversity of heterochromatin in prochilodontid fish

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Maria L. Terencio

2015-08-01

Full Text Available The structure and organization of repetitive elements in fish genomes are still relatively poorly understood, although most of these elements are believed to be located in heterochromatic regions. Repetitive elements are considered essential in evolutionary processes as hotspots for mutations and chromosomal rearrangements, among other functions – thus providing new genomic alternatives and regulatory sites for gene expression. The present study sought to characterize repetitive DNA sequences in the genomes of Semaprochilodus insignis (Jardine & Schomburgk, 1841 and Semaprochilodus taeniurus (Valenciennes, 1817 and identify regions of conserved syntenic blocks in this genome fraction of three species of Prochilodontidae (S. insignis, S. taeniurus, and Prochilodus lineatus (Valenciennes, 1836 by cross-FISH using Cot-1 DNA (renaturation kinetics probes. We found that the repetitive fractions of the genomes of S. insignis and S. taeniurus have significant amounts of conserved syntenic blocks in hybridization sites, but with low degrees of similarity between them and the genome of P. lineatus, especially in relation to B chromosomes. The cloning and sequencing of the repetitive genomic elements of S. insignis and S. taeniurus using Cot-1 DNA identified 48 fragments that displayed high similarity with repetitive sequences deposited in public DNA databases and classified as microsatellites, transposons, and retrotransposons. The repetitive fractions of the S. insignis and S. taeniurus genomes exhibited high degrees of conserved syntenic blocks in terms of both the structures and locations of hybridization sites, but a low degree of similarity with the syntenic blocks of the P. lineatus genome. Future comparative analyses of other prochilodontidae species will be needed to advance our understanding of the organization and evolution of the genomes in this group of fish.

Hemispheric Asymmetries in Repetition Enhancement and Suppression Effects in the Newborn Brain.

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Bouchon, Camillia; Nazzi, Thierry; Gervain, Judit

2015-01-01

The repeated presentation of stimuli typically attenuates neural responses (repetition suppression) or, less commonly, increases them (repetition enhancement) when stimuli are highly complex, degraded or presented under noisy conditions. In adult functional neuroimaging research, these repetition effects are considered as neural correlates of habituation. The development and respective functional significance of these effects in infancy remain largely unknown. This study investigates repetition effects in newborns using functional near-infrared spectroscopy, and specifically the role of stimulus complexity in evoking a repetition enhancement vs. a repetition suppression response, following up on Gervain et al. (2008). In that study, abstract rule-learning was found at birth in cortical areas specific to speech processing, as evidenced by a left-lateralized repetition enhancement of the hemodynamic response to highly variable speech sequences conforming to a repetition-based ABB artificial grammar, but not to a random ABC grammar. Here, the same paradigm was used to investigate how simpler stimuli (12 different sequences per condition as opposed to 140), and simpler presentation conditions (blocked rather than interleaved) would influence repetition effects at birth. Results revealed that the two grammars elicited different dynamics in the two hemispheres. In left fronto-temporal areas, we reproduce the early perceptual discrimination of the two grammars, with ABB giving rise to a greater response at the beginning of the experiment than ABC. In addition, the ABC grammar evoked a repetition enhancement effect over time, whereas a stable response was found for the ABB grammar. Right fronto-temporal areas showed neither initial discrimination, nor change over time to either pattern. Taken together with Gervain et al. (2008), this is the first evidence that manipulating methodological factors influences the presence or absence of neural repetition enhancement effects in

Hemispheric Asymmetries in Repetition Enhancement and Suppression Effects in the Newborn Brain.

Directory of Open Access Journals (Sweden)

Camillia Bouchon

Full Text Available The repeated presentation of stimuli typically attenuates neural responses (repetition suppression or, less commonly, increases them (repetition enhancement when stimuli are highly complex, degraded or presented under noisy conditions. In adult functional neuroimaging research, these repetition effects are considered as neural correlates of habituation. The development and respective functional significance of these effects in infancy remain largely unknown.This study investigates repetition effects in newborns using functional near-infrared spectroscopy, and specifically the role of stimulus complexity in evoking a repetition enhancement vs. a repetition suppression response, following up on Gervain et al. (2008. In that study, abstract rule-learning was found at birth in cortical areas specific to speech processing, as evidenced by a left-lateralized repetition enhancement of the hemodynamic response to highly variable speech sequences conforming to a repetition-based ABB artificial grammar, but not to a random ABC grammar.Here, the same paradigm was used to investigate how simpler stimuli (12 different sequences per condition as opposed to 140, and simpler presentation conditions (blocked rather than interleaved would influence repetition effects at birth.Results revealed that the two grammars elicited different dynamics in the two hemispheres. In left fronto-temporal areas, we reproduce the early perceptual discrimination of the two grammars, with ABB giving rise to a greater response at the beginning of the experiment than ABC. In addition, the ABC grammar evoked a repetition enhancement effect over time, whereas a stable response was found for the ABB grammar. Right fronto-temporal areas showed neither initial discrimination, nor change over time to either pattern.Taken together with Gervain et al. (2008, this is the first evidence that manipulating methodological factors influences the presence or absence of neural repetition enhancement

A clinical repetitive transcranial magnetic stimulation service in Australia: 6 years on.

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Galletly, Cherrie A; Clarke, Patrick; Carnell, Benjamin L; Gill, Shane

2015-11-01

There is considerable research evidence for the effectiveness of repetitive transcranial magnetic stimulation in the treatment of depression. However, there is little information about its acceptability and outcomes in clinical settings. This naturalistic study reports on a clinical repetitive transcranial magnetic stimulation service that has been running in Adelaide, South Australia (SA), for 6 years. During this time, 214 complete acute courses were provided to patients with treatment-resistant Major Depressive Disorder. Patients received either sequential bilateral or right unilateral repetitive transcranial magnetic stimulation treatment involving either 18 or 20 sessions given over 6 or 4 weeks respectively. Data included patient demographic details, duration of depression, and medication at the beginning of their repetitive transcranial magnetic stimulation course. The Hamilton Depression Rating Scale was used to assess response to repetitive transcranial magnetic stimulation. Of those undergoing a first-time acute treatment course of repetitive transcranial magnetic stimulation (N = 167), 28% achieved remission, while a further 12% met the criteria for a response to treatment. Most patients (N = 123, 77%) had previously been treated with five or more antidepressant medications, and 77 (47%) had previously received electroconvulsive therapy. Referral rates remained high over the 6 years, indicating acceptance of the treatment by referring psychiatrists. There were no significant adverse events, and the treatment was generally well tolerated. In all, 41 patients (25%) had a second course of repetitive transcranial magnetic stimulation and 6 (4%) patients had a third course; 21 patients subsequently received maintenance repetitive transcranial magnetic stimulation. This naturalistic study showed that repetitive transcranial magnetic stimulation was well accepted by both psychiatrists and patients, and has good efficacy and safety. Furthermore

A repetitive elements perspective in Polycomb epigenetics.

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Valentina eCasa

2012-10-01

Full Text Available Repetitive elements comprise over two-thirds of the human genome. For a long time, these elements have received little attention since they were considered non functional. On the contrary, recent evidence indicates that they play central roles in genome integrity, gene expression and disease. Indeed, repeats display meiotic instability associated with disease and are located within common fragile sites, which are hotspots of chromosome rearrangements in tumors. Moreover, a variety of diseases have been associated with aberrant transcription of repetitive elements. Overall this indicates that appropriate regulation of repetitive elements’ activity is fundamental.Polycomb group (PcG proteins are epigenetic regulators that are essential for the normal development of multicellular organisms. Mammalian PcG proteins are involved in fundamental processes, such as cellular memory, cell proliferation, genomic imprinting, X-inactivation, and cancer development. PcG proteins can convey their activity through long-distance interactions also on different chromosomes. This indicates that the 3D organization of PcG proteins contributes significantly to their function. However, it is still unclear how these complex mechanisms are orchestrated and which role PcG proteins play in the multi-level organization of gene regulation. Intriguingly, the greatest proportion of Polycomb-mediated chromatin modifications is located in genomic repeats and it has been suggested that they could provide a binding platform for Polycomb proteins.Here, these lines of evidence are woven together to discuss how repetitive elements could contribute to chromatin organization in the 3D nuclear space.

A feasible repetitive transcranial magnetic stimulation clinical protocol in migraine prevention.

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Zardouz, Shawn; Shi, Lei; Leung, Albert

2016-01-01

This case series was conducted to determine the clinical feasibility of a repetitive transcranial magnetic stimulation protocol for the prevention of migraine (with and without aura). Five patients with migraines underwent five repetitive transcranial magnetic stimulation sessions separated in 1- to 2-week intervals for a period of 2 months at a single tertiary medical center. Repetitive transcranial magnetic stimulation was applied to the left motor cortex with 2000 pulses (20 trains with 1s inter-train interval) delivered per session, at a frequency of 10 Hz and 80% resting motor threshold. Pre- and post-treatment numerical rating pain scales were collected, and percent reductions in intensity, frequency, and duration were generated. An average decrease in 37.8%, 32.1%, and 31.2% were noted in the intensity, frequency, and duration of migraines post-repetitive transcranial magnetic stimulation, respectively. A mean decrease in 1.9±1.0 (numerical rating pain scale ± standard deviation; range: 0.4-2.8) in headache intensity scores was noted after the repetitive transcranial magnetic stimulation sessions. The tested repetitive transcranial magnetic stimulation protocol is a well-tolerated, safe, and effective method for migraine prevention.

High-repetition-rate short-pulse gas discharge.

Science.gov (United States)

Tulip, J; Seguin, H; Mace, P N

1979-09-01

A high-average-power short-pulse gas discharge is described. This consists of a volume-preionized transverse discharge of the type used in gas lasers driven by a Blumlein energy storage circuit. The Blumlein circuit is fabricated from coaxial cable, is pulse-charged from a high-repetition-rate Marx-bank generator, and is switched by a high-repetition-rate segmented rail gap. The operation of this discharge under conditions typical of rare-gas halide lasers is described. A maximum of 900 pps was obtained, giving a power flow into the discharge of 30 kW.

Repetitively pulsed, double discharge TEA CO/sub 2/ laser

Energy Technology Data Exchange (ETDEWEB)

Hamilton, D C; James, D J; Ramsden, S A

1975-10-01

The design and operation of a repetitively pulsed TEA CO/sub 2/ laser is described. Average powers of up to 400 W at a repetition frequency of 200 pulses/s have been obtained. The system has also been used to provide long pulses (over 20 ..mu..s) and tunable single axial mode pulses.

Modeling repetitive motions using structured light.

Science.gov (United States)

Xu, Yi; Aliaga, Daniel G

2010-01-01

Obtaining models of dynamic 3D objects is an important part of content generation for computer graphics. Numerous methods have been extended from static scenarios to model dynamic scenes. If the states or poses of the dynamic object repeat often during a sequence (but not necessarily periodically), we call such a repetitive motion. There are many objects, such as toys, machines, and humans, undergoing repetitive motions. Our key observation is that when a motion-state repeats, we can sample the scene under the same motion state again but using a different set of parameters; thus, providing more information of each motion state. This enables robustly acquiring dense 3D information difficult for objects with repetitive motions using only simple hardware. After the motion sequence, we group temporally disjoint observations of the same motion state together and produce a smooth space-time reconstruction of the scene. Effectively, the dynamic scene modeling problem is converted to a series of static scene reconstructions, which are easier to tackle. The varying sampling parameters can be, for example, structured-light patterns, illumination directions, and viewpoints resulting in different modeling techniques. Based on this observation, we present an image-based motion-state framework and demonstrate our paradigm using either a synchronized or an unsynchronized structured-light acquisition method.

Manifestation of Incompleteness in Obsessive-Compulsive Disorder (OCD) as Reduced Functionality and Extended Activity beyond Task Completion

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Zor, Rama; Szechtman, Henry; Hermesh, Haggai; Fineberg, Naomi A.; Eilam, David

2011-01-01

Background This study focused on hypotheses regarding the source of incompleteness in obsessive-compulsive disorder (OCD). For this, we had to document the behavioral manifestation of incompleteness in compulsive rituals, predicting that an exaggerated focus on acts that are appropriate for the task will support the hypothesis on heightened responsibility/perfectionism. In contrast, activity past the expected terminal act for the motor task would support the “stop signal deficiency” hypothesis. Methodology and Principal Findings We employed video-telemetry to analyze 39 motor OCD rituals and compared each with a similar task performed by a non-OCD individual, in order to objectively and explicitly determine the functional end of the activity. We found that 75% of OCD rituals comprised a “tail,” which is a section that follows the functional end of the task that the patients ascribed to their activity. The other 25% tailless rituals comprised a relatively high number and higher rate of repetition of non-functional acts. Thus, in rituals with tail, incompleteness was manifested by the mere presence of the tail whereas in tailless rituals, incompleteness was manifested by the reduced functionality of the task due to an inflated execution and repetition of non-functional acts. Conclusions The prevalence of activity after the functional end (“tail”) and the elevated non-functionality in OCD motor rituals support the “lack of stop signal” theories as the underlying mechanism in OCD. Furthermore, the presence and content of the tail might have a therapeutic potential in cognitive-behavior therapy. PMID:21966460

Many Neighbors are not Silent. fMRI Evidence for Global Lexical Activity in Visual Word Recognition.

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Mario eBraun

2015-07-01

Full Text Available Many neurocognitive studies investigated the neural correlates of visual word recognition, some of which manipulated the orthographic neighborhood density of words and nonwords believed to influence the activation of orthographically similar representations in a hypothetical mental lexicon. Previous neuroimaging research failed to find evidence for such global lexical activity associated with neighborhood density. Rather, effects were interpreted to reflect semantic or domain general processing. The present fMRI study revealed effects of lexicality, orthographic neighborhood density and a lexicality by orthographic neighborhood density interaction in a silent reading task. For the first time we found greater activity for words and nonwords with a high number of neighbors. We propose that this activity in the dorsomedial prefrontal cortex reflects activation of orthographically similar codes in verbal working memory thus providing evidence for global lexical activity as the basis of the neighborhood density effect. The interaction of lexicality by neighborhood density in the ventromedial prefrontal cortex showed lower activity in response to words with a high number compared to nonwords with a high number of neighbors. In the light of these results the facilitatory effect for words and inhibitory effect for nonwords with many neighbors observed in previous studies can be understood as being due to the operation of a fast-guess mechanism for words and a temporal deadline mechanism for nonwords as predicted by models of visual word recognition. Furthermore, we propose that the lexicality effect with higher activity for words compared to nonwords in inferior parietal and middle temporal cortex reflects the operation of an identification mechanism and based on local lexico-semantic activity.

Semantic Neighborhood Effects for Abstract versus Concrete Words.

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Danguecan, Ashley N; Buchanan, Lori

2016-01-01

Studies show that semantic effects may be task-specific, and thus, that semantic representations are flexible and dynamic. Such findings are critical to the development of a comprehensive theory of semantic processing in visual word recognition, which should arguably account for how semantic effects may vary by task. It has been suggested that semantic effects are more directly examined using tasks that explicitly require meaning processing relative to those for which meaning processing is not necessary (e.g., lexical decision task). The purpose of the present study was to chart the processing of concrete versus abstract words in the context of a global co-occurrence variable, semantic neighborhood density (SND), by comparing word recognition response times (RTs) across four tasks varying in explicit semantic demands: standard lexical decision task (with non-pronounceable non-words), go/no-go lexical decision task (with pronounceable non-words), progressive demasking task, and sentence relatedness task. The same experimental stimulus set was used across experiments and consisted of 44 concrete and 44 abstract words, with half of these being low SND, and half being high SND. In this way, concreteness and SND were manipulated in a factorial design using a number of visual word recognition tasks. A consistent RT pattern emerged across tasks, in which SND effects were found for abstract (but not necessarily concrete) words. Ultimately, these findings highlight the importance of studying interactive effects in word recognition, and suggest that linguistic associative information is particularly important for abstract words.

Body-focused repetitive behavior disorders in ICD-11

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Jon E. Grant

2014-01-01

Full Text Available This article addresses the question of how body-focused repetitive behavior disorders (e.g., trichotillomania and skin-picking disorder should be characterized in ICD-11. The article reviews the historical nosology of the two disorders and the current approaches in DSM-5 and ICD-10. Although data are limited and mixed regarding the optimal relationship between body-focused repetitive behavior disorders and nosological categories, these conditions should be included within the obsessive-compulsive and related disorders category, as this is how most clinicians see these behaviors, and as this may optimize clinical utility. The descriptions of these disorders should largely mirror those in DSM-5, given the evidence from recent field surveys. The recommendations regarding ICD-11 and body-focused repetitive behavior disorders should promote the global identification and treatment of these conditions in primary care settings.

Preferences for cervical cancer screening: The role of implicit associations

NARCIS (Netherlands)

Korfage, I.J.; Kwaadsteniet, E.W. de; Voorst, A. van; Stiggelbout, A.M.; Vries, M. de; Pieterse, A.H.

2018-01-01

Objectives: Implicit associations influence behaviour, but their impact on cancer screening intentions is unknown. Methods: We assessed implicit associations with cervical cancer screening using an evaluative priming task. Participants were shown primes ('Pap test', neutral or non-word) followed by

Repetition suppression and multi-voxel pattern similarity differentially track implicit and explicit visual memory.

Science.gov (United States)

Ward, Emily J; Chun, Marvin M; Kuhl, Brice A

2013-09-11

Repeated exposure to a visual stimulus is associated with corresponding reductions in neural activity, particularly within visual cortical areas. It has been argued that this phenomenon of repetition suppression is related to increases in processing fluency or implicit memory. However, repetition of a visual stimulus can also be considered in terms of the similarity of the pattern of neural activity elicited at each exposure--a measure that has recently been linked to explicit memory. Despite the popularity of each of these measures, direct comparisons between the two have been limited, and the extent to which they differentially (or similarly) relate to behavioral measures of memory has not been clearly established. In the present study, we compared repetition suppression and pattern similarity as predictors of both implicit and explicit memory. Using functional magnetic resonance imaging, we scanned 20 participants while they viewed and categorized repeated presentations of scenes. Repetition priming (facilitated categorization across repetitions) was used as a measure of implicit memory, and subsequent scene recognition was used as a measure of explicit memory. We found that repetition priming was predicted by repetition suppression in prefrontal, parietal, and occipitotemporal regions; however, repetition priming was not predicted by pattern similarity. In contrast, subsequent explicit memory was predicted by pattern similarity (across repetitions) in some of the same occipitotemporal regions that exhibited a relationship between priming and repetition suppression; however, explicit memory was not related to repetition suppression. This striking double dissociation indicates that repetition suppression and pattern similarity differentially track implicit and explicit learning.

Progress in developing repetitive pulse systems utilizing inductive energy storage

Energy Technology Data Exchange (ETDEWEB)

Honig, E.M.

1983-01-01

High-power, fast-recovery vacuum switches were used in a new repetitive counterpulse and transfer circuit to deliver a 5-kHz pulse train with a peak power of 75 MW (at 8.6 kA) to a 1-..cap omega.. load, resulting in the first demonstration of fully controlled, high-power, high-repetition-rate operation of an inductive energy-storage and transfer system with nondestructive switches. New circuits, analytical and experimental results, and feasibility of 100-kV repetitive pulse generation are discussed. A new switching concept for railgun loads is presented.

Trait Cheerfulness Does Not Influence Switching Costs But Modulates Preparation and Repetition Effects in a Task-Switching Paradigm

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Raúl López-Benítez

2017-06-01

Full Text Available Many studies have shown the beneficial effect of positive emotions on various cognitive processes, such as creativity and cognitive flexibility. Cheerfulness, understood as an affective predisposition to sense of humor, has been associated with positive emotions. So far, however, no studies have shown the relevance of this dimension in cognitive flexibility processes. The aim of this research was to analyze the relationship between cheerfulness and these processes. To this end, we carried out two studies using a task-switching paradigm. Study 1 aimed at analyzing whether high trait cheerfulness was related to better cognitive flexibility (as measured by reduced task-switching costs, whereas Study 2 aimed at replicating the pattern of data observed in Study 1. The total sample was composed of 139 participants (of which 86 were women selected according to their high versus low scores in trait cheerfulness. In a random way, participants had to judge whether the face presented to them in each trial was that of a man or a woman (gender recognition task or whether it expressed anger or happiness (expressed emotion recognition task. We expected participants with high versus low trait cheerfulness to show a lower task-switching cost (i.e., higher cognitive flexibility. Results did not confirm this hypothesis. However, in both studies, participants with high versus low trait cheerfulness showed a higher facilitation effect when the stimuli attributes were repeated and also when a cue was presented anticipating the demand to perform. We discuss the relevance of these results for a better understanding of cheerfulness.

Repetitive laser fusion experiment and operation using a target injection system

International Nuclear Information System (INIS)

Nishimura, Yasuhiko; Komeda, Osamu; Mori, Yoshitaka

2017-01-01

Since 2008, a collaborative research project on laser fusion development based on a high-speed ignition method using repetitive laser has been carried out with several collaborative research institutes. This paper reports the current state of operation of high repetition laser fusion experiments, such as target introduction and control based on a target injection system that allows free falling under 1 Hz, using a high repetition laser driver that has been under research and development, as well as the measurement of targets that freely fall. The HAMA laser driver that enabled high repetition fusion experiments is a titanium sapphire laser using a diode-pumped solid-state laser KURE-I of green light output as a driver pump light source. In order to carry out high repetition laser fusion experiments, the target injection device allows free falling of deuterated polystyrene solid sphere targets of 1 mm in diameter under 1 Hz. The authors integrated the developed laser and injection system, and succeeded first in the world in making the nuclear fusion reaction continuously by hitting the target to be injected with laser, which is essential technology for future laser nuclear fusion reactor. In order to realize repetition laser fusion experiments, stable laser, target synchronization control, and target position measurement technologies are indispensable. (A.O.)

A software platform to develop and execute kitting tasks on industrial cyber-physical systems

DEFF Research Database (Denmark)

Rovida, Francesco

2017-01-01

The current material handling infrastructure associated with manufacturing and assembly operations still register a great presence of human work for highly repetitive tasks. A major contributing factor for the low automation is that current manufacturing robots have little or no understanding of ....... A platform where skills, similarly to computer or smartphone applications, can be installed and removed from heterogeneous robots with few elementary steps....

The Effect of Concurrent Semantic Categorization on Delayed Serial Recall

Science.gov (United States)

Acheson, Daniel J.; MacDonald, Maryellen C.; Postle, Bradley R.

2010-01-01

The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Subjects engaged in two picture judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content (concrete words in Experiment 1 and 3; nonwords in Experiments 2 and 3). Picture judgments varied in the extent to which they required accessing visual semantic information (i.e., semantic categorization and line orientation judgments). Results showed that, relative to line orientation judgments, engaging in semantic categorization judgments increased the proportion of item ordering errors for concrete lists but did not affect error proportions for nonword lists. Furthermore, although more ordering errors were observed for phonologically similar relative to dissimilar lists, no interactions were observed between the phonological overlap and picture judgment task manipulations. These results thus demonstrate that lexical-semantic representations can affect the serial ordering of items in short-term memory. Furthermore, the dual-task paradigm provides a new method for examining when and how semantic representations affect memory performance. PMID:21058880

Domain-specific and domain-general constraints on word and sequence learning.

Science.gov (United States)

Archibald, Lisa M D; Joanisse, Marc F

2013-02-01

The relative influences of language-related and memory-related constraints on the learning of novel words and sequences were examined by comparing individual differences in performance of children with and without specific deficits in either language or working memory. Children recalled lists of words in a Hebbian learning protocol in which occasional lists repeated, yielding improved recall over the course of the task on the repeated lists. The task involved presentation of pictures of common nouns followed immediately by equivalent presentations of the spoken names. The same participants also completed a paired-associate learning task involving word-picture and nonword-picture pairs. Hebbian learning was observed for all groups. Domain-general working memory constrained immediate recall, whereas language abilities impacted recall in the auditory modality only. In addition, working memory constrained paired-associate learning generally, whereas language abilities disproportionately impacted novel word learning. Overall, all of the learning tasks were highly correlated with domain-general working memory. The learning of nonwords was additionally related to general intelligence, phonological short-term memory, language abilities, and implicit learning. The results suggest that distinct associations between language- and memory-related mechanisms support learning of familiar and unfamiliar phonological forms and sequences.

Repetition or Reconfiguration

DEFF Research Database (Denmark)

Andersen, Kristina Vaarst

, the cognitive quality of knowledge held by individual professionals is the key microfoundation for project level performance. This paper empirically tests effects of project participants with and without knowledge diversity for project level performance for projects aiming for varying degrees of repetition...... and reconfiguration. The results indicate that project performance benefits form contributions from individuals holding diverse knowledge only when projects aim for high differentiation levels. This positive association is not just moderated, it may even be reversed in the case of professionals participating in low...

Visual attention to advertising : The impact of motivation and repetition

NARCIS (Netherlands)

Pieters, RGM; Rosbergen, E; Hartog, M; Corfman, KP; Lynch, JG

1996-01-01

Using eye-tracking data, we examine the impact of motivation and repetition on visual attention to advertisements differing in argument quality. Our analyses indicate that repetition leads to an overall decrease in the amount of attention. However, while at first high motivation subjects attend to

Normative data for distal line bisection and baking tray task.

Science.gov (United States)

Facchin, Alessio; Beschin, Nicoletta; Pisano, Alessia; Reverberi, Cristina

2016-09-01

Line bisection is one of the tests used to diagnose unilateral spatial neglect (USN). Despite its wide application, no procedure or norms were available for the distal variant when the task was performed at distance with a laser pointer. Furthermore, the baking tray task was an ecological test aimed at diagnosing USN in a more natural context. The aim of this study was to collect normative values for these two tests in an Italian population. We recruited a sample of 191 healthy subjects with ages ranging from 20 to 89 years. They performed line bisection with a laser pointer on three different line lengths (1, 1.5, and 2 m) at a distance of 3 m. After this task, the subjects performed the baking tray task and a second repetition of line bisection to test the reliability of measurement. Multiple regression analysis revealed no significant effects of demographic variables on the performance of both tests. Normative cut-off values for the two tests were developed using non-parametric tolerance intervals. The results formed the basis for clinical use of these two tools for assessing lateralized performance of patients with brain injury and for diagnosing USN.

Pull-production in repetitive remanufacturing

Energy Technology Data Exchange (ETDEWEB)

McCaskey, D.W. Jr.

1992-09-01

In the past, production activity control practices in most repetitive remanufacturing facilities resembled those used in intermittent production operations. These operations were characterized by large amounts of work-in-process (WIP), frequent work stoppages due to part shortages, excessive overtime, low product velocity, informal scheduling between dependent operations, low employee and management moral, and a lot of wasted time, material, labor, and space. Improvement in production activity control (PAC) methods for repetitive remanufactures has been hampered by uncertainty in: supply of incoming assets, configuration of assets, process times to refurbish assets, and yields in reclamation processes. collectively these uncertainties make shop floor operations seem uncontrollable. However, one United States Army depot has taken on the challenge. Through management supported, cross-functional teams, the Tooele Army Depot has designed and implemented pull-production systems for two of its major products, with several others to follow. This article presents a generalized version of Tooele`s pull-production system and highlights design characteristics which are specific to remanufacturing applications.

Pull-production in repetitive remanufacturing

Energy Technology Data Exchange (ETDEWEB)

McCaskey, D.W. Jr.

1992-09-01

In the past, production activity control practices in most repetitive remanufacturing facilities resembled those used in intermittent production operations. These operations were characterized by large amounts of work-in-process (WIP), frequent work stoppages due to part shortages, excessive overtime, low product velocity, informal scheduling between dependent operations, low employee and management moral, and a lot of wasted time, material, labor, and space. Improvement in production activity control (PAC) methods for repetitive remanufactures has been hampered by uncertainty in: supply of incoming assets, configuration of assets, process times to refurbish assets, and yields in reclamation processes. collectively these uncertainties make shop floor operations seem uncontrollable. However, one United States Army depot has taken on the challenge. Through management supported, cross-functional teams, the Tooele Army Depot has designed and implemented pull-production systems for two of its major products, with several others to follow. This article presents a generalized version of Tooele's pull-production system and highlights design characteristics which are specific to remanufacturing applications.

The influence of phonetic dimensions on aphasic speech perception

NARCIS (Netherlands)

de Kok, D.A.; Jonkers, R.; Bastiaanse, Y.R.M.

2010-01-01

Individuals with aphasia have more problems detecting small differences between speech sounds than larger ones. This paper reports how phonemic processing is impaired and how this is influenced by speechreading. A non-word discrimination task was carried out with 'audiovisual', 'auditory only' and

Active power filter for harmonic compensation using a digital dual-mode-structure repetitive control approach

DEFF Research Database (Denmark)

Zou, Zhixiang; Wang, Zheng; Cheng, Ming

2012-01-01

This paper presents an digital dual-mode-structure repetitive control approach for the single-phase shunt active power filter (APF), which aims to enhance the tracking ability and eliminate arbitrary order harmonic. The proposed repetitive control scheme blends the characteristics of both odd......-harmonic repetitive control and even-harmonic repetitive control. Moreover, the convergence rate is faster than conventional repetitive controller. Additionally, the parameters have been designed and optimized for the dual-mode structure repetitive control to improve the performance of APF system. Experimental...

Negative effects of item repetition on source memory

OpenAIRE

Kim, Kyungmi; Yi, Do-Joon; Raye, Carol L.; Johnson, Marcia K.

2012-01-01

In the present study, we explored how item repetition affects source memory for new item–feature associations (picture–location or picture–color). We presented line drawings varying numbers of times in Phase 1. In Phase 2, each drawing was presented once with a critical new feature. In Phase 3, we tested memory for the new source feature of each item from Phase 2. Experiments 1 and 2 demonstrated and replicated the negative effects of item repetition on incidental source memory. Prior item re...

Repetitive transcranial magnetic stimulation for hallucination in schizophrenia spectrum disorders: A meta-analysis.

Science.gov (United States)

Zhang, Yingli; Liang, Wei; Yang, Shichang; Dai, Ping; Shen, Lijuan; Wang, Changhong

2013-10-05

This study assessed the efficacy and tolerability of repetitive transcranial magnetic stimulation for treatment of auditory hallucination of patients with schizophrenia spectrum disorders. Online literature retrieval was conducted using PubMed, ISI Web of Science, EMBASE, Medline and Cochrane Central Register of Controlled Trials databases from January 1985 to May 2012. Key words were "transcranial magnetic stimulation", "TMS", "repetitive transcranial magnetic stimulation", and "hallucination". Selected studies were randomized controlled trials assessing therapeutic efficacy of repetitive transcranial magnetic stimulation for hallucination in patients with schizophrenia spectrum disorders. Experimental intervention was low-frequency repetitive transcranial magnetic stimulation in left temporoparietal cortex for treatment of auditory hallucination in schizophrenia spectrum disorders. Control groups received sham stimulation. The primary outcome was total scores of Auditory Hallucinations Rating Scale, Auditory Hallucination Subscale of Psychotic Symptom Rating Scale, Positive and Negative Symptom Scale-Auditory Hallucination item, and Hallucination Change Scale. Secondary outcomes included response rate, global mental state, adverse effects and cognitive function. Seventeen studies addressing repetitive transcranial magnetic stimulation for treatment of schizophrenia spectrum disorders were screened, with controls receiving sham stimulation. All data were completely effective, involving 398 patients. Overall mean weighted effect size for repetitive transcranial magnetic stimulation versus sham stimulation was statistically significant (MD = -0.42, 95%CI: -0.64 to -0.20, P = 0.000 2). Patients receiving repetitive transcranial magnetic stimulation responded more frequently than sham stimulation (OR = 2.94, 95%CI: 1.39 to 6.24, P = 0.005). No significant differences were found between active repetitive transcranial magnetic stimulation and sham stimulation for

Understanding the relationship between repetition priming and mere exposure.

Science.gov (United States)

Butler, Laurie T; Berry, Dianne C

2004-11-01

Over the last two decades interest in implicit memory, most notably repetition priming, has grown considerably. During the same period, research has also focused on the mere exposure effect. Although the two areas have developed relatively independently, a number of studies has described the mere exposure effect as an example of implicit memory. Tacit in their comparisons is the assumption that the effect is more specifically a demonstration of repetition priming. Having noted that this assumption has attracted relatively little attention, this paper reviews current evidence and shows that it is by no means conclusive. Although some evidence is suggestive of a common underlying mechanism, even a modified repetition priming (perceptual fluency/attribution) framework cannot accommodate all of the differences between the two phenomena. Notwithstanding this, it seems likely that a version of this theoretical framework still offers the best hope of a comprehensive explanation for the mere exposure effect and its relationship to repetition priming. As such, the paper finishes by offering some initial guidance as to ways in which the perceptual fluency/attribution framework might be extended, as well as outlining important areas for future research.

Working memory span in Persian-speaking children with speech sound disorders and normal speech development.

Science.gov (United States)

Afshar, Mohamad Reza; Ghorbani, Ali; Rashedi, Vahid; Jalilevand, Nahid; Kamali, Mohamad

2017-10-01

The aim of this study was to compare working memory span in Persian-speaking preschool children with speech sound disorder (SSD) and their typically speaking peers. Additionally, the study aimed to examine Non-Word Repetition (NWR), Forward Digit Span (FDS) and Backward Digit Span (BDS) in four groups of children with varying severity levels of SSD. The participants in this study comprised 35 children with SSD and 35 typically developing (TD) children -matched for age and sex-as a control group. The participants were between the age range of 48 and 72 months. Two components of working memory including phonological loop and central executive were compared between two groups. We used two tasks (NWR and FDS) to assess phonological loop component, and one task (BDS) to assess central executive component. Percentage of correct consonants (PCC) was used to calculate the severity of SSD. Significant differences were observed between the two groups in all tasks that assess working memory (p working memory between the various severity groups indicated significant differences between different severities of both NWR and FDS tasks among the SSD children (p  0.05). The result showed that PCC scores in TD children were associated with NWR (p  0.05). The working memory skills were weaker in SSD children, in comparison to TD children. In addition, children with varying levels of severity of SSD differed in terms of NWR and FSD, but not BDS. Copyright © 2017 Elsevier B.V. All rights reserved.

Initiating an ergonomic analysis. A process for jobs with highly variable tasks.

Science.gov (United States)

Conrad, K M; Lavender, S A; Reichelt, P A; Meyer, F T

2000-09-01

Occupational health nurses play a vital role in addressing ergonomic problems in the workplace. Describing and documenting exposure to ergonomic risk factors is a relatively straightforward process in jobs in which the work is repetitive. In other types of work, the analysis becomes much more challenging because tasks may be repeated infrequently, or at irregular time intervals, or under different environmental and temporal conditions, thereby making it difficult to observe a "representative" sample of the work performed. This article describes a process used to identify highly variable job tasks for ergonomic analyses. The identification of tasks for ergonomic analysis was a two step process involving interviews and a survey of firefighters and paramedics from a consortium of 14 suburban fire departments. The interviews were used to generate a list of frequently performed, physically strenuous job tasks and to capture clear descriptions of those tasks and associated roles. The goals of the survey were to confirm the interview findings across the entire target population and to quantify the frequency and degree of strenuousness of each task. In turn, the quantitative results from the survey were used to prioritize job tasks for simulation. Although this process was used to study firefighters and paramedics, the approach is likely to be suitable for many other types of occupations in which the tasks are highly variable in content and irregular in frequency.

Cerebellar tDCS does not affect performance in the N-back task.

Science.gov (United States)

van Wessel, Brenda W V; Claire Verhage, M; Holland, Peter; Frens, Maarten A; van der Geest, Jos N

2016-01-01

The N-back task is widely used in cognitive research. Furthermore, the cerebellum's role in cognitive processes is becoming more widely recognized. Studies using transcranial direct current stimulation (tDCS) have demonstrated effects of cerebellar stimulation on several cognitive tasks. Therefore, the aim of this study was to investigate the effects of cerebellar tDCS on cognitive performance by using the N-back task. The cerebellum of 12 participants was stimulated during the task. Moreover, the cognitive load was manipulated in N = 2, N = 3, and N = 4. Every participant received three tDCS conditions (anodal, cathodal, and sham) divided over three separated days. It was expected that anodal stimulation would improve performance on the task. Each participant performed 6 repetitions of every load in which correct responses, false alarms, and reaction times were recorded. We found significant differences between the three levels of load in the rate of correct responses and false alarms, indicating that subjects followed the expected pattern of performance for the N-back task. However, no significant differences between the three tDCS conditions were found. Therefore, it was concluded that in this study cognitive performance on the N-back task was not readily influenced by cerebellar tDCS, and any true effects are likely to be small. We discuss several limitations in task design and suggest future experiments to address such issues.

The intractability of non-word production difficulties in jargon aphasia: Insights from therapy

Directory of Open Access Journals (Sweden)

Arpita Bose

2015-04-01

Full Text Available Severe word production difficulties remain one of the most challenging clinical symptoms to treat in individuals with jargon aphasia (JA. Although research has found a beneficial effect of phonological therapy in JA (e.g., FF in Bose 2013; GF in Robson et al., 1998, a lack of improvement in naming performance following this approach has also been reported (e.g., P9 in Leonard et al., 2008. Clinically, it is important to determine why some individuals with JA improve following phonological therapy when others do not. This research investigates the effect of phonological therapy on naming performance in JA and explores possible reasons for improvement or lack thereof (e.g., input/ output processing skills, ability to use and maintain cues. Methods Participant: AM, an 86 year old, English-speaking male, was 16 years post-stroke and presented with persistent, severe neologistic jargon, characterized by very high proportions of non-words and perseverations. Part 1: Effects of phonological cuing (initial phoneme vs. semantic cuing (semantically-related item on naming performance were tested on items from the Philadelphia Naming Test (Roach et al., 1996 to determine the most suitable course of therapy. Part 2: Using a single-subject multiple baseline design, Phonological Component Analysis (Leonard et al., 2008 was administered for three sets of words. In addition to analysis of therapy performance, naming accuracy was compared across three lists in three instances of a word being treated (i.e., 1st attempt without any phonological cues, 2nd attempt immediately after the phonological cues, and 3rd attempt after review of the phonological cues. Results and Discussion Part 1: Results showed a significant increase in naming accuracy following phonological cuing [χ2 (1 = 5.782, p = .01], whereas semantic cuing did not [χ2 (1 =.386, ns], thus motivating the implementation of a phonological therapy. Part 2: There was a significant difference in accuracy

Hierarchical classification of dynamically varying radar pulse repetition interval modulation patterns.

Science.gov (United States)

Kauppi, Jukka-Pekka; Martikainen, Kalle; Ruotsalainen, Ulla

2010-12-01

The central purpose of passive signal intercept receivers is to perform automatic categorization of unknown radar signals. Currently, there is an urgent need to develop intelligent classification algorithms for these devices due to emerging complexity of radar waveforms. Especially multifunction radars (MFRs) capable of performing several simultaneous tasks by utilizing complex, dynamically varying scheduled waveforms are a major challenge for automatic pattern classification systems. To assist recognition of complex radar emissions in modern intercept receivers, we have developed a novel method to recognize dynamically varying pulse repetition interval (PRI) modulation patterns emitted by MFRs. We use robust feature extraction and classifier design techniques to assist recognition in unpredictable real-world signal environments. We classify received pulse trains hierarchically which allows unambiguous detection of the subpatterns using a sliding window. Accuracy, robustness and reliability of the technique are demonstrated with extensive simulations using both static and dynamically varying PRI modulation patterns. Copyright © 2010 Elsevier Ltd. All rights reserved.

Neural Patterns of Reorganization after Intensive Robot-Assisted Virtual Reality Therapy and Repetitive Task Practice in Patients with Chronic Stroke

Directory of Open Access Journals (Sweden)

Soha Saleh

2017-09-01

Full Text Available Several approaches to rehabilitation of the hand following a stroke have emerged over the last two decades. These treatments, including repetitive task practice (RTP, robotically assisted rehabilitation and virtual rehabilitation activities, produce improvements in hand function but have yet to reinstate function to pre-stroke levels—which likely depends on developing the therapies to impact cortical reorganization in a manner that favors or supports recovery. Understanding cortical reorganization that underlies the above interventions is therefore critical to inform how such therapies can be utilized and improved and is the focus of the current investigation. Specifically, we compare neural reorganization elicited in stroke patients participating in two interventions: a hybrid of robot-assisted virtual reality (RAVR rehabilitation training and a program of RTP training. Ten chronic stroke subjects participated in eight 3-h sessions of RAVR therapy. Another group of nine stroke subjects participated in eight sessions of matched RTP therapy. Functional magnetic resonance imaging (fMRI data were acquired during paretic hand movement, before and after training. We compared the difference between groups and sessions (before and after training in terms of BOLD intensity, laterality index of activation in sensorimotor areas, and the effective connectivity between ipsilesional motor cortex (iMC, contralesional motor cortex, ipsilesional primary somatosensory cortex (iS1, ipsilesional ventral premotor area (iPMv, and ipsilesional supplementary motor area. Last, we analyzed the relationship between changes in fMRI data and functional improvement measured by the Jebsen Taylor Hand Function Test (JTHFT, in an attempt to identify how neurophysiological changes are related to motor improvement. Subjects in both groups demonstrated motor recovery after training, but fMRI data revealed RAVR-specific changes in neural reorganization patterns. First, BOLD

Neural Patterns of Reorganization after Intensive Robot-Assisted Virtual Reality Therapy and Repetitive Task Practice in Patients with Chronic Stroke.

Science.gov (United States)

Saleh, Soha; Fluet, Gerard; Qiu, Qinyin; Merians, Alma; Adamovich, Sergei V; Tunik, Eugene

2017-01-01

Several approaches to rehabilitation of the hand following a stroke have emerged over the last two decades. These treatments, including repetitive task practice (RTP), robotically assisted rehabilitation and virtual rehabilitation activities, produce improvements in hand function but have yet to reinstate function to pre-stroke levels-which likely depends on developing the therapies to impact cortical reorganization in a manner that favors or supports recovery. Understanding cortical reorganization that underlies the above interventions is therefore critical to inform how such therapies can be utilized and improved and is the focus of the current investigation. Specifically, we compare neural reorganization elicited in stroke patients participating in two interventions: a hybrid of robot-assisted virtual reality (RAVR) rehabilitation training and a program of RTP training. Ten chronic stroke subjects participated in eight 3-h sessions of RAVR therapy. Another group of nine stroke subjects participated in eight sessions of matched RTP therapy. Functional magnetic resonance imaging (fMRI) data were acquired during paretic hand movement, before and after training. We compared the difference between groups and sessions (before and after training) in terms of BOLD intensity, laterality index of activation in sensorimotor areas, and the effective connectivity between ipsilesional motor cortex (iMC), contralesional motor cortex, ipsilesional primary somatosensory cortex (iS1), ipsilesional ventral premotor area (iPMv), and ipsilesional supplementary motor area. Last, we analyzed the relationship between changes in fMRI data and functional improvement measured by the Jebsen Taylor Hand Function Test (JTHFT), in an attempt to identify how neurophysiological changes are related to motor improvement. Subjects in both groups demonstrated motor recovery after training, but fMRI data revealed RAVR-specific changes in neural reorganization patterns. First, BOLD signal in multiple

How Does L1 and L2 Exposure Impact L1 Performance in Bilingual Children? Evidence from Polish-English Migrants to the United Kingdom

Directory of Open Access Journals (Sweden)

Ewa Haman

2017-09-01

Full Text Available Most studies on bilingual language development focus on children’s second language (L2. Here, we investigated first language (L1 development of Polish-English early migrant bilinguals in four domains: vocabulary, grammar, phonological processing, and discourse. We first compared Polish language skills between bilinguals and their Polish non-migrant monolingual peers, and then investigated the influence of the cumulative exposure to L1 and L2 on bilinguals’ performance. We then examined whether high exposure to L1 could possibly minimize the gap between monolinguals and bilinguals. We analyzed data from 233 typically developing children (88 bilingual and 145 monolingual aged 4;0 to 7;5 (years;months on six language measures in Polish: receptive vocabulary, productive vocabulary, receptive grammar, productive grammar (sentence repetition, phonological processing (non-word repetition, and discourse abilities (narration. Information about language exposure was obtained via parental questionnaires. For each language task, we analyzed the data from the subsample of bilinguals who had completed all the tasks in question and from monolinguals matched one-on-one to the bilingual group on age, SES (measured by years of mother’s education, gender, non-verbal IQ, and short-term memory. The bilingual children scored lower than monolinguals in all language domains, except discourse. The group differences were more pronounced on the productive tasks (vocabulary, grammar, and phonological processing and moderate on the receptive tasks (vocabulary and grammar. L1 exposure correlated positively with the vocabulary size and phonological processing. Grammar scores were not related to the levels of L1 exposure, but were predicted by general cognitive abilities. L2 exposure negatively influenced productive grammar in L1, suggesting possible L2 transfer effects on L1 grammatical performance. Children’s narrative skills benefitted from exposure to two languages

Aging, Emotion, Attention, and Binding in the Taboo Stroop Task: Data and Theories

Science.gov (United States)

MacKay, Donald G.; Johnson, Laura W.; Graham, Elizabeth R.; Burke, Deborah M.

2015-01-01

How does aging impact relations between emotion, memory, and attention? To address this question, young and older adults named the font colors of taboo and neutral words, some of which recurred in the same font color or screen location throughout two color-naming experiments. The results indicated longer color-naming response times (RTs) for taboo than neutral base-words (taboo Stroop interference); better incidental recognition of colors and locations consistently associated with taboo versus neutral words (taboo context-memory enhancement); and greater speed-up in color-naming RTs with repetition of color-consistent than color-inconsistent taboo words, but no analogous speed-up with repetition of location-consistent or location-inconsistent taboo words (the consistency type by repetition interaction for taboo words). All three phenomena remained constant with aging, consistent with the transmission deficit hypothesis and binding theory, where familiar emotional words trigger age-invariant reactions for prioritizing the binding of contextual features to the source of emotion. Binding theory also accurately predicted the interaction between consistency type and repetition for taboo words. However, one or more aspects of these phenomena failed to support the inhibition deficit hypothesis, resource capacity theory, or socio-emotional selectivity theory. We conclude that binding theory warrants further test in a range of paradigms, and that relations between aging and emotion, memory, and attention may depend on whether the task and stimuli trigger fast-reaction, involuntary binding processes, as in the taboo Stroop paradigm. PMID:26473909

Aging, Emotion, Attention, and Binding in the Taboo Stroop Task: Data and Theories

Directory of Open Access Journals (Sweden)

Donald G. MacKay

2015-10-01

Full Text Available How does aging impact relations between emotion, memory, and attention? To address this question, young and older adults named the font colors of taboo and neutral words, some of which recurred in the same font color or screen location throughout two color-naming experiments. The results indicated longer color-naming response times (RTs for taboo than neutral base-words (taboo Stroop interference; better incidental recognition of colors and locations consistently associated with taboo versus neutral words (taboo context-memory enhancement; and greater speed-up in color-naming RTs with repetition of color-consistent than color-inconsistent taboo words, but no analogous speed-up with repetition of location-consistent or location-inconsistent taboo words (the consistency type by repetition interaction for taboo words. All three phenomena remained constant with aging, consistent with the transmission deficit hypothesis and binding theory, where familiar emotional words trigger age-invariant reactions for prioritizing the binding of contextual features to the source of emotion. Binding theory also accurately predicted the interaction between consistency type and repetition for taboo words. However, one or more aspects of these phenomena failed to support the inhibition deficit hypothesis, resource capacity theory, or socio-emotional selectivity theory. We conclude that binding theory warrants further test in a range of paradigms, and that relations between aging and emotion, memory, and attention may depend on whether the task and stimuli trigger fast-reaction, involuntary binding processes, as in the taboo Stroop paradigm.

Aging, Emotion, Attention, and Binding in the Taboo Stroop Task: Data and Theories.

Science.gov (United States)

MacKay, Donald G; Johnson, Laura W; Graham, Elizabeth R; Burke, Deborah M

2015-10-14

How does aging impact relations between emotion, memory, and attention? To address this question, young and older adults named the font colors of taboo and neutral words, some of which recurred in the same font color or screen location throughout two color-naming experiments. The results indicated longer color-naming response times (RTs) for taboo than neutral base-words (taboo Stroop interference); better incidental recognition of colors and locations consistently associated with taboo versus neutral words (taboo context-memory enhancement); and greater speed-up in color-naming RTs with repetition of color-consistent than color-inconsistent taboo words, but no analogous speed-up with repetition of location-consistent or location-inconsistent taboo words (the consistency type by repetition interaction for taboo words). All three phenomena remained constant with aging, consistent with the transmission deficit hypothesis and binding theory, where familiar emotional words trigger age-invariant reactions for prioritizing the binding of contextual features to the source of emotion. Binding theory also accurately predicted the interaction between consistency type and repetition for taboo words. However, one or more aspects of these phenomena failed to support the inhibition deficit hypothesis, resource capacity theory, or socio-emotional selectivity theory. We conclude that binding theory warrants further test in a range of paradigms, and that relations between aging and emotion, memory, and attention may depend on whether the task and stimuli trigger fast-reaction, involuntary binding processes, as in the taboo Stroop paradigm.

Sound-symbolism boosts novel word learning

NARCIS (Netherlands)

Lockwood, G.F.; Dingemanse, M.; Hagoort, P.

2016-01-01

The existence of sound-symbolism (or a non-arbitrary link between form and meaning) is well-attested. However, sound-symbolism has mostly been investigated with nonwords in forced choice tasks, neither of which are representative of natural language. This study uses ideophones, which are naturally

Characterization and distribution of repetitive elements in association with genes in the human genome.

Science.gov (United States)

Liang, Kai-Chiang; Tseng, Joseph T; Tsai, Shaw-Jenq; Sun, H Sunny

2015-08-01

Repetitive elements constitute more than 50% of the human genome. Recent studies implied that the complexity of living organisms is not just a direct outcome of a number of coding sequences; the repetitive elements, which do not encode proteins, may also play a significant role. Though scattered studies showed that repetitive elements in the regulatory regions of a gene control gene expression, no systematic survey has been done to report the characterization and distribution of various types of these repetitive elements in the human genome. Sequences from 5' and 3' untranslated regions and upstream and downstream of a gene were downloaded from the Ensembl database. The repetitive elements in the neighboring of each gene were identified and classified using cross-matching implemented in the RepeatMasker. The annotation and distribution of distinct classes of repetitive elements associated with individual gene were collected to characterize genes in association with different types of repetitive elements using systems biology program. We identified a total of 1,068,400 repetitive elements which belong to 37-class families and 1235 subclasses that are associated with 33,761 genes and 57,365 transcripts. In addition, we found that the tandem repeats preferentially locate proximal to the transcription start site (TSS) of genes and the major function of these genes are involved in developmental processes. On the other hand, interspersed repetitive elements showed a tendency to be accumulated at distal region from the TSS and the function of interspersed repeat-containing genes took part in the catabolic/metabolic processes. Results from the distribution analysis were collected and used to construct a gene-based repetitive element database (GBRED; http://www.binfo.ncku.edu.tw/GBRED/index.html). A user-friendly web interface was designed to provide the information of repetitive elements associated with any particular gene(s). This is the first study focusing on the gene

Repetitive Bibliographical Information in Relational Databases.

Science.gov (United States)

Brooks, Terrence A.

1988-01-01

Proposes a solution to the problem of loading repetitive bibliographic information in a microcomputer-based relational database management system. The alternative design described is based on a representational redundancy design and normalization theory. (12 references) (Author/CLB)

A copper bromide vapour laser with a high pulse repetition rate

International Nuclear Information System (INIS)

Shiyanov, D V; Evtushenko, Gennadii S; Sukhanov, V B; Fedorov, V F

2002-01-01

The results of an experimental study of a copper bromide vapour laser with a discharge-channel diameter above 2.5 cm and a high pump-pulse repetition rate are presented. A TGU1-1000/25 high-power tacitron used as a switch made it possible to obtain for the first time a fairly high output radiation power for pump-pulse repetition rates exceeding 200 kHz. At a maximum pump-pulse repetition rate of 250 kHz achieved in a laser tube 2.6 cm in diameter and 76 cm long, the output power was 1.5 W. The output powers of 3 and 10.5 W were reached for pump-pulse repetition rates of 200 and 100 kHz, respectively. These characteristics were obtained without circulating a buffer gas and (or) low-concentration active impurities through the active volume. (active media. lasers)

The repetition effect in building and construction works

DEFF Research Database (Denmark)

Gottlieb, Stefan Christoffer; Haugbølle, Kim

are then applied on the Public Transport Authorities' main account structure of units and costs, and a method for assessing the possibilities of achieving effects of repetition for each account is described. Finally, the report summarises the core conditions necessary to take into consideration in relation......This report summarises the results from the work undertaken for the Public Transport Authority on the effect of learning and repetition in building and construction works. The results are applied by the Public Transport Authority in a new budgeting model, while the agency investigates...

Repetitive transcranial magnetic stimulation for hallucination in schizophrenia spectrum disorders A meta-analysis***

Institute of Scientific and Technical Information of China (English)

Yingli Zhang; Wei Liang; Shichang Yang; Ping Dai; Lijuan Shen; Changhong Wang

2013-01-01

OBJECTIVE: This study assessed the efficacy and tolerability of repetitive transcranial magnetic stimulation for treatment of auditory hal ucination of patients with schizophrenia spectrum disorders. DATA SOURCES: Online literature retrieval was conducted using PubMed, ISI Web of Science, EMBASE, Medline and Cochrane Central Register of Control ed Trials databases from January 1985 to May 2012. Key words were “transcranial magnetic stimulation”, “TMS”, “repetitive transcranial magnetic stimulation”, and “hal ucination”. STUDY SELECTION: Selected studies were randomized control ed trials assessing therapeutic ef-ficacy of repetitive transcranial magnetic stimulation for hal ucination in patients with schizophrenia spectrum disorders. Experimental intervention was low-frequency repetitive transcranial magnetic stimulation in left temporoparietal cortex for treatment of auditory hal ucination in schizophrenia spectrum disorders. Control groups received sham stimulation. MAIN OUTCOME MEASURES: The primary outcome was total scores of Auditory Hal ucinations Rating Scale, Auditory Hal ucination Subscale of Psychotic Symptom Rating Scale, Positive and Negative Symptom Scale-Auditory Hal ucination item, and Hal ucination Change Scale. Secondary outcomes included response rate, global mental state, adverse effects and cognitive function. RESULTS: Seventeen studies addressing repetitive transcranial magnetic stimulation for treatment of schizophrenia spectrum disorders were screened, with controls receiving sham stimulation. Al data were completely effective, involving 398 patients. Overal mean weighted effect size for repeti-tive transcranial magnetic stimulation versus sham stimulation was statistical y significant (MD =-0.42, 95%CI: -0.64 to -0.20, P = 0.000 2). Patients receiving repetitive transcranial magnetic stimulation responded more frequently than sham stimulation (OR = 2.94, 95%CI: 1.39 to 6.24, P =0.005). No significant differences were found

Comparison of concentric and eccentric bench press repetitions to failure.

Science.gov (United States)

Kelly, Stephen B; Brown, Lee E; Hooker, Steven P; Swan, Pamela D; Buman, Matthew P; Alvar, Brent A; Black, Laurie E

2015-04-01

Eccentric muscle actions (ECC) are characterized by muscle lengthening, despite actin-myosin crossbridge formation. Muscles acting eccentrically are capable of producing higher levels of force compared with muscles acting concentrically. The purpose of this study was to determine whether ECC bench press yields greater strength than concentric (CON) as determined by 1 repetition maximum (1RM). Additionally, a comparison was made examining differences in the number of repetitions to failure at different relative intensities of 1RM. Thirty healthy men (age = 24.63 ± 5.6 years) were tested for 1RM in CON and ECC bench press and the number of repetitions completed at 60, 70, 80, and 90% 1RM. For CON repetitions, the weight was mechanically lowered to the chest, and the participant pressed it up until the elbows were fully extended. The ECC bench press consisted of lowering a barbell from a fully extended elbow position to the chest in a continuous controlled manner for 3 seconds as determined by electronic metronome. Paired t-tests showed that ECC 1RM (115.99 ± 31.08 kg) was significantly (p ≤ 0.05) greater than CON 1RM (93.56 ± 26.56 kg), and the number of repetitions completed at 90% 1RM was significantly (p ≤ 0.05) greater in ECC (7.67 ± 3.24) as compared with CON (4.57 ± 2.21). There were no significant differences in number of completed repetitions during CON and ECC bench press at 60, 70, and 80% 1RM. These data indicate that ECC actions yield increased force capabilities (∼120%) as compared with CON in the bench press and may be less prone to fatigue, especially at higher intensities. These differences suggest a need to develop unique strategies for training eccentrically.

Pulsed electron beam generation with fast repetitive double pulse system

Energy Technology Data Exchange (ETDEWEB)

Sharma, Surender Kumar; Deb, Pankaj; Shyam, Anurag, E-mail: surender80@gmail.com [Energetics and Electromagnetics Division, Bhabha Atomic Research Centre, Visakhapatnam (India); Sharma, Archana [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Mumbai (India)

2014-07-01

Longer duration high voltage pulse (∼ 100 kV, 260 ns) is generated and reported using helical pulse forming line in compact geometry. The transmission line characteristics of the helical pulse forming line are also used to develop fast repetition double pulse system with very short inter pulse interval. It overcomes the limitations caused due to circuit parameters, power supplies and load characteristics for fast repetitive high voltage pulse generation. The high voltage double pulse of 100 kV, 100 ns with an inter pulse repetition interval of 30 ns is applied across the vacuum field emission diode for pulsed electron beam generation. The electron beam is generated from cathode material by application of negative high voltage (> 100 kV) across the diode by explosive electron emission process. The vacuum field emission diode is made of 40 mm diameter graphite cathode and SS mesh anode. The anode cathode gap was 6 mm and the drift tube diameter was 10 cm. The initial experimental results of pulsed electron beam generation with fast repetitive double pulse system are reported and discussed. (author)

Repetitive trauma and nerve compression.

Science.gov (United States)

Carragee, E J; Hentz, V R

1988-01-01

Repetitive movement of the upper extremity, whether recreational or occupational, may result in various neuropathies, the prototype of which is the median nerve neuropathic in the carpal canal. The pathophysiology of this process is incompletely understood but likely involves both mechanical and ischemic features. Experimentally increased pressures within the carpal canal produced reproducible progressive neuropathy. Changes in vibratory (threshold-type) sensibility appears to be more sensitive than two-point (innervation density-type) sensibility. The specific occupational etiologies of carpal neuropathy are obscured by methodologic and sociological difficulties, but clearly some occupations have high incidences of CTS. History and physical examination are usually sufficient for the diagnosis, but diagnostic assistance when required is available through electrophysiological testing, CT scanning, and possibly MRI. Each of these tests has limitations in both sensitivity and specificity. Treatment by usual conservative means should be combined with rest from possible provocative activities. Surgical release of the carpal canal is helpful in patients failing conservative therapy. Occupational modifications are important in both treatment and prevention of median neuropathy due to repetitive trauma.

Priming in implicit memory tasks: prior study causes enhanced discriminability, not only bias.

Science.gov (United States)

Zeelenberg, René; Wagenmakers, Eric-Jan M; Raaijmakers, Jeroen G W

2002-03-01

R. Ratcliff and G. McKoon (1995, 1996, 1997; R. Ratcliff, D. Allbritton, & G. McKoon, 1997) have argued that repetition priming effects are solely due to bias. They showed that prior study of the target resulted in a benefit in a later implicit memory task. However, prior study of a stimulus similar to the target resulted in a cost. The present study, using a 2-alternative forced-choice procedure, investigated the effect of prior study in an unbiased condition: Both alternatives were studied prior to their presentation in an implicit memory task. Contrary to a pure bias interpretation of priming, consistent evidence was obtained in 3 implicit memory tasks (word fragment completion, auditory word identification, and picture identification) that performance was better when both alternatives were studied than when neither alternative was studied. These results show that prior study results in enhanced discriminability, not only bias.

Repetitive Elements in Mycoplasma hyopneumoniae Transcriptional Regulation.

Directory of Open Access Journals (Sweden)

Amanda Malvessi Cattani

Full Text Available Transcriptional regulation, a multiple-step process, is still poorly understood in the important pig pathogen Mycoplasma hyopneumoniae. Basic motifs like promoters and terminators have already been described, but no other cis-regulatory elements have been found. DNA repeat sequences have been shown to be an interesting potential source of cis-regulatory elements. In this work, a genome-wide search for tandem and palindromic repetitive elements was performed in the intergenic regions of all coding sequences from M. hyopneumoniae strain 7448. Computational analysis demonstrated the presence of 144 tandem repeats and 1,171 palindromic elements. The DNA repeat sequences were distributed within the 5' upstream regions of 86% of transcriptional units of M. hyopneumoniae strain 7448. Comparative analysis between distinct repetitive sequences found in related mycoplasma genomes demonstrated different percentages of conservation among pathogenic and nonpathogenic strains. qPCR assays revealed differential expression among genes showing variable numbers of repetitive elements. In addition, repeats found in 206 genes already described to be differentially regulated under different culture conditions of M. hyopneumoniae strain 232 showed almost 80% conservation in relation to M. hyopneumoniae strain 7448 repeats. Altogether, these findings suggest a potential regulatory role of tandem and palindromic DNA repeats in the M. hyopneumoniae transcriptional profile.

Repetitive Elements in Mycoplasma hyopneumoniae Transcriptional Regulation.

Science.gov (United States)

Cattani, Amanda Malvessi; Siqueira, Franciele Maboni; Guedes, Rafael Lucas Muniz; Schrank, Irene Silveira

2016-01-01

Transcriptional regulation, a multiple-step process, is still poorly understood in the important pig pathogen Mycoplasma hyopneumoniae. Basic motifs like promoters and terminators have already been described, but no other cis-regulatory elements have been found. DNA repeat sequences have been shown to be an interesting potential source of cis-regulatory elements. In this work, a genome-wide search for tandem and palindromic repetitive elements was performed in the intergenic regions of all coding sequences from M. hyopneumoniae strain 7448. Computational analysis demonstrated the presence of 144 tandem repeats and 1,171 palindromic elements. The DNA repeat sequences were distributed within the 5' upstream regions of 86% of transcriptional units of M. hyopneumoniae strain 7448. Comparative analysis between distinct repetitive sequences found in related mycoplasma genomes demonstrated different percentages of conservation among pathogenic and nonpathogenic strains. qPCR assays revealed differential expression among genes showing variable numbers of repetitive elements. In addition, repeats found in 206 genes already described to be differentially regulated under different culture conditions of M. hyopneumoniae strain 232 showed almost 80% conservation in relation to M. hyopneumoniae strain 7448 repeats. Altogether, these findings suggest a potential regulatory role of tandem and palindromic DNA repeats in the M. hyopneumoniae transcriptional profile.

Raven's matrices and working memory: a dual-task approach.

Science.gov (United States)

Rao, K Venkata; Baddeley, Alan

2013-01-01

Raven's Matrices Test was developed as a "pure" measure of Spearman's concept of general intelligence, g. Subsequent research has attempted to specify the processes underpinning performance, some relating it to the concept of working memory and proposing a crucial role for the central executive, with the nature of other components currently unclear. Up to this point, virtually all work has been based on correlational analysis of number of correct solutions, sometimes related to possible strategies. We explore the application to this problem of the concurrent task methodology used widely in developing the concept of multicomponent working memory. Participants attempted to solve problems from the matrices under baseline conditions, or accompanied by backward counting or verbal repetition tasks, assumed to disrupt the central executive and phonological loop components of working memory, respectively. As in other uses of this method, number of items correct showed little effect, while solution time measures gave very clear evidence of an important role for the central executive, but no evidence for phonological loop involvement. We conclude that this and related concurrent task techniques hold considerable promise for the analysis of Raven's matrices and potentially for other established psychometric tests.

REPETITIVE TMS ON LEFT CEREBELLUM AFFECTS IMPULSIVITY IN BORDERLINE PERSONALITY DISORDER : A PILOT STUDY

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Giulia Zelda De Vidovich

2016-12-01

Full Text Available The borderline personality disorder (BPD is characterized by a severe pattern of instability in emotional regulation, interpersonal relationships, identity, and impulse control. These functions are related to the prefrontal cortex (PFC, and since PFC shows a rich anatomical connectivity with the cerebellum, the functionality of the cerebellar-PFC axis may impact on BPD. In this study we investigated the potential involvement of cerebello-thalamo-cortical connections in impulsive reactions through a pre/post stimulation design. BPD patients (n=8 and healthy controls (HC; n=9 performed an Affective Go/No-Go task (AGN assessing information processing biases for positive and negative stimuli before and after repetitive transcranial magnetic stimulation (rTMS; 1 Hz/10 min, 80% RMT over the left lateral cerebellum. The AGN task consisted of four blocks requiring associative capacities of increasing complexity. BPD patients performed significantly worse than the HC, especially when cognitive demands was high (3rd and 4th block, but their performace approached that of HC after rTMS (rTMS was almost ineffective in HC. The more evident effect of rTMS in complex associative tasks might have occurred since the cerebellum is deeply involved in integration and coordination of different stimuli. We hypothesize that, in BPD patients, cerebello-thalamo-cortical communication is altered, resulting in emotional dysregulation and disturbed impulse control. The rTMS over the left cerebellum might have interfered with existing functional connections exerting a facilitating effect on PFC control.

Repetitive TMS on Left Cerebellum Affects Impulsivity in Borderline Personality Disorder: A Pilot Study.

Science.gov (United States)

De Vidovich, Giulia Zelda; Muffatti, Riccardo; Monaco, Jessica; Caramia, Nicoletta; Broglia, Davide; Caverzasi, Edgardo; Barale, Francesco; D'Angelo, Egidio

2016-01-01

The borderline personality disorder (BPD) is characterized by a severe pattern of instability in emotional regulation, interpersonal relationships, identity and impulse control. These functions are related to the prefrontal cortex (PFC), and since PFC shows a rich anatomical connectivity with the cerebellum, the functionality of the cerebellar-PFC axis may impact on BPD. In this study, we investigated the potential involvement of cerebello-thalamo-cortical connections in impulsive reactions through a pre/post stimulation design. BPD patients ( n = 8) and healthy controls (HC; n = 9) performed an Affective Go/No-Go task (AGN) assessing information processing biases for positive and negative stimuli before and after repetitive transcranial magnetic stimulation (rTMS; 1 Hz/10 min, 80% resting motor threshold (RMT) over the left lateral cerebellum. The AGN task consisted of four blocks requiring associative capacities of increasing complexity. BPD patients performed significantly worse than the HC, especially when cognitive demands were high (third and fourth block), but their performance approached that of HC after rTMS (rTMS was almost ineffective in HC). The more evident effect of rTMS in complex associative tasks might have occurred since the cerebellum is deeply involved in integration and coordination of different stimuli. We hypothesize that in BPD patients, cerebello-thalamo-cortical communication is altered, resulting in emotional dysregulation and disturbed impulse control. The rTMS over the left cerebellum might have interfered with existing functional connections exerting a facilitating effect on PFC control.

A long-pulse repetitive operation magnetically insulated transmission line oscillator

International Nuclear Information System (INIS)

Fan, Yu-Wei; Zhong, Hui-Huang; Zhang, Jian-De; Shu, Ting; Liu, Jin Liang

2014-01-01

The improved magnetically insulated transmission line oscillator (MILO) is a gigawatt-class L-band high power microwave tube. It has allowed us to generate 3.1 GW pulse of 40 ns duration in the single-pulse operation and 500 MW pulse of 25 ns duration in the repetition rate operation. However, because of the severe impedance mismatch, the power conversion efficiency is only about 4% in the repetition rate operation. In order to eliminate the impedance mismatch and obtain repetitive long-pulse high-power microwave (HPM), a series of experiments are carried out and the recent progress is presented in this paper. In the single-pulse operation, when the diode voltage is 466 kV and current is 41.6 kA, the radiated microwave power is above 2.2 GW, the pulse duration is above 102 ns, the microwave frequency is about 1.74 GHz, and the power conversion efficiency is about 11.5%. In the repetition rate operation, under the condition of the diode voltage about 400 kV, beam current about 38 kA, the radiated microwave power is about 1.0 GW, the pulse duration is about 85 ns. Moreover, the radiated microwave power and the pulse duration decline little by little when the shot numbers increase gradually. The experimental results show that the impedance matching is a vital factor for HPM systems and one of the major technical challenges is to improve the cathode for the repetition rate operation MILO

A long-pulse repetitive operation magnetically insulated transmission line oscillator

Energy Technology Data Exchange (ETDEWEB)

Fan, Yu-Wei; Zhong, Hui-Huang; Zhang, Jian-De; Shu, Ting; Liu, Jin Liang [College of Optoelectric Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

2014-05-15

The improved magnetically insulated transmission line oscillator (MILO) is a gigawatt-class L-band high power microwave tube. It has allowed us to generate 3.1 GW pulse of 40 ns duration in the single-pulse operation and 500 MW pulse of 25 ns duration in the repetition rate operation. However, because of the severe impedance mismatch, the power conversion efficiency is only about 4% in the repetition rate operation. In order to eliminate the impedance mismatch and obtain repetitive long-pulse high-power microwave (HPM), a series of experiments are carried out and the recent progress is presented in this paper. In the single-pulse operation, when the diode voltage is 466 kV and current is 41.6 kA, the radiated microwave power is above 2.2 GW, the pulse duration is above 102 ns, the microwave frequency is about 1.74 GHz, and the power conversion efficiency is about 11.5%. In the repetition rate operation, under the condition of the diode voltage about 400 kV, beam current about 38 kA, the radiated microwave power is about 1.0 GW, the pulse duration is about 85 ns. Moreover, the radiated microwave power and the pulse duration decline little by little when the shot numbers increase gradually. The experimental results show that the impedance matching is a vital factor for HPM systems and one of the major technical challenges is to improve the cathode for the repetition rate operation MILO.

A long-pulse repetitive operation magnetically insulated transmission line oscillator.

Science.gov (United States)

Fan, Yu-Wei; Zhong, Hui-Huang; Zhang, Jian-De; Shu, Ting; Liu, Jin Liang

2014-05-01

The improved magnetically insulated transmission line oscillator (MILO) is a gigawatt-class L-band high power microwave tube. It has allowed us to generate 3.1 GW pulse of 40 ns duration in the single-pulse operation and 500 MW pulse of 25 ns duration in the repetition rate operation. However, because of the severe impedance mismatch, the power conversion efficiency is only about 4% in the repetition rate operation. In order to eliminate the impedance mismatch and obtain repetitive long-pulse high-power microwave (HPM), a series of experiments are carried out and the recent progress is presented in this paper. In the single-pulse operation, when the diode voltage is 466 kV and current is 41.6 kA, the radiated microwave power is above 2.2 GW, the pulse duration is above 102 ns, the microwave frequency is about 1.74 GHz, and the power conversion efficiency is about 11.5%. In the repetition rate operation, under the condition of the diode voltage about 400 kV, beam current about 38 kA, the radiated microwave power is about 1.0 GW, the pulse duration is about 85 ns. Moreover, the radiated microwave power and the pulse duration decline little by little when the shot numbers increase gradually. The experimental results show that the impedance matching is a vital factor for HPM systems and one of the major technical challenges is to improve the cathode for the repetition rate operation MILO.

Repetitive elements in parasitic protozoa

Directory of Open Access Journals (Sweden)

Clayton Christine

2010-05-01

Full Text Available Abstract A recent paper published in BMC Genomics suggests that retrotransposition may be active in the human gut parasite Entamoeba histolytica. This adds to our knowledge of the various types of repetitive elements in parasitic protists and the potential influence of such elements on pathogenicity. See research article http://www.biomedcentral.com/1471-2164/11/321

The effects of dual tasking on handwriting in patients with Parkinson's disease.

Science.gov (United States)

Broeder, S; Nackaerts, E; Nieuwboer, A; Smits-Engelsman, B C M; Swinnen, S P; Heremans, E

2014-03-28

Previous studies have shown that patients with Parkinson's disease (PD) experience extensive problems during dual tasking. Up to now, dual-task interference in PD has mainly been investigated in the context of gait research. However, the simultaneous performance of two different tasks is also a prerequisite to efficiently perform many other tasks in daily life, including upper limb tasks. To address this issue, this study investigated the effect of a secondary cognitive task on the performance of handwriting in patients with PD. Eighteen PD patients and 11 age-matched controls performed a writing task involving the production of repetitive loops under single- and dual-task conditions. The secondary task consisted of counting high and low tones during writing. The writing tests were performed with two amplitudes (0.6 and 1.0cm) using a writing tablet. Results showed that dual-task performance was affected in PD patients versus controls. Dual tasking reduced writing amplitude in PD patients, but not in healthy controls (p=0.046). Patients' writing size was mainly reduced during the small-amplitude condition (small amplitude p=0.017; large amplitude p=0.310). This suggests that the control of writing at small amplitudes requires more compensational brain-processing recourses in PD and is as such less automatic than writing at large amplitudes. In addition, there was a larger dual-task effect on the secondary task in PD patients than controls (p=0.025). The writing tests on the writing tablet proved highly correlated to daily life writing as measured by the 'Systematic Screening of Handwriting Difficulties' test (SOS-test) and other manual dexterity tasks, particularly during dual-task conditions. Taken together, these results provide additional insights into the motor control of handwriting and the effects of dual tasking during upper limb movements in patients with PD. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Oxotremorine treatment reduces repetitive behaviors in BTBR T+ tf/J mice

Directory of Open Access Journals (Sweden)

Dionisio A. Amodeo

2014-08-01

Full Text Available Repetitive behaviors with restricted interests is one of the core criteria for the diagnosis of autism spectrum disorder (ASD. Current pharmacotherapies that target the dopaminergic or serotonergic systems have limited effectiveness in treating repetitive behaviors. Previous research has demonstrated that administration of muscarinic cholinergic receptor (mAChR antagonists can exacerbate motor stereotypies while mAChR agonists reduce stereotypies. The present study determined whether the mAChR agonist, oxotremorine affected repetitive behaviors in the BTBR T+ tf/J (BTBR mouse model of autism. To test the effects of oxotremorine on repetitive behaviors, marble burying and grooming behavior were measured in BTBR mice and compared to that in C57BL/6J (B6 mice. The effects of oxotremorine on locomotor activity was also measured. Thirty minutes before each test, mice received an intraperitoneal injection of saline, 0.001 mg or 0.01 mg of oxotremorine methiodide. Saline- treated BTBR mice exhibited increased marble burying and self-grooming behavior compared to that of saline-treated B6 mice. Oxotremorine significantly reduced marble burying and self-grooming behavior in BTBR mice, but had no significant effect in B6 mice. In addition, oxotremorine did not affect locomotor activity in BTBR mice, but significantly reduced locomotor activity in B6 mice at the 0.01 mg dose. These findings demonstrate that activation of mAChRs reduces repetitive behavior in the BTBR mouse and suggest that treatment with a mAChR agonist may be effective in reducing repetitive behaviors in ASD.

Optimality based repetitive controller design for track-following servo system of optical disk drives.

Science.gov (United States)

Chen, Wentao; Zhang, Weidong

2009-10-01

In an optical disk drive servo system, to attenuate the external periodic disturbances induced by inevitable disk eccentricity, repetitive control has been used successfully. The performance of a repetitive controller greatly depends on the bandwidth of the low-pass filter included in the repetitive controller. However, owing to the plant uncertainty and system stability, it is difficult to maximize the bandwidth of the low-pass filter. In this paper, we propose an optimality based repetitive controller design method for the track-following servo system with norm-bounded uncertainties. By embedding a lead compensator in the repetitive controller, both the system gain at periodic signal's harmonics and the bandwidth of the low-pass filter are greatly increased. The optimal values of the repetitive controller's parameters are obtained by solving two optimization problems. Simulation and experimental results are provided to illustrate the effectiveness of the proposed method.

Combined effect of repetitive work and cold on muscle function and fatigue.

Science.gov (United States)

Oksa, Juha; Ducharme, Michel B; Rintamäki, Hannu

2002-01-01

This study compared the effect of repetitive work in thermoneutral and cold conditions on forearm muscle electromyogram (EMG) and fatigue. We hypothesize that cold and repetitive work together cause higher EMG activity and fatigue than repetitive work only, thus creating a higher risk for overuse injuries. Eight men performed six 20-min work bouts at 25 degrees C (W-25) and at 5 degrees C while exposed to systemic (C-5) and local cooling (LC-5). The work was wrist flexion-extension exercise at 10% maximal voluntary contraction. The EMG activity of the forearm flexors and extensors was higher during C-5 (31 and 30%, respectively) and LC-5 (25 and 28%, respectively) than during W-25 (P forearm flexors at the end of W-25 was 15%. The corresponding values at the end of C-5 and LC-5 were 37% (P < 0.05 in relation to W-25) and 20%, respectively. Thus repetitive work in the cold causes higher EMG activity and fatigue than repetitive work in thermoneutral conditions.

Illusory sensation of movement induced by repetitive transcranial magnetic stimulation

DEFF Research Database (Denmark)

Christensen, Mark Schram; Lundbye-Jensen, Jesper; Grey, Michael James

2010-01-01

Human movement sense relies on both somatosensory feedback and on knowledge of the motor commands used to produce the movement. We have induced a movement illusion using repetitive transcranial magnetic stimulation over primary motor cortex and dorsal premotor cortex in the absence of limb movement...... and its associated somatosensory feedback. Afferent and efferent neural signalling was abolished in the arm with ischemic nerve block, and in the leg with spinal nerve block. Movement sensation was assessed following trains of high-frequency repetitive transcranial magnetic stimulation applied over...... premotor cortex stimulation was less affected by sensory and motor deprivation than was primary motor cortex stimulation. We propose that repetitive transcranial magnetic stimulation over dorsal premotor cortex produces a corollary discharge that is perceived as movement....

A Performance Study on Synchronous and Asynchronous Update Rules for A Plug-In Direct Particle Swarm Repetitive Controller

Directory of Open Access Journals (Sweden)

Ufnalski Bartlomiej

2014-12-01

Full Text Available In this paper two different update schemes for the recently developed plug-in direct particle swarm repetitive controller (PDPSRC are investigated and compared. The proposed approach employs the particle swarm optimizer (PSO to solve in on-line mode a dynamic optimization problem (DOP related to the control task in the constant-amplitude constant-frequency voltage-source inverter (CACF VSI with an LC output filter. The effectiveness of synchronous and asynchronous update rules, both commonly used in static optimization problems (SOPs, is assessed and compared in the case of PDPSRC. The performance of the controller, when synthesized using each of the update schemes, is studied numerically.

Effectiveness of Non-pharmacological Interventions on Stereotyped and Repetitive Behaviors in Preschool Children With Autism: A Systematic Review

Directory of Open Access Journals (Sweden)

Hadi Zarafshan

2017-03-01

Full Text Available Objective: The present study aimed to review the literature on non-pharmacological interventions used to treat stereotyped and repetitive behaviors by a systematic method. Methods: Two authors independently performed a search strategy on Medline/PubMed, Scopus and PsycINFO on English articles published up to April 23, 2014 with relevant search keywords. We also reviewed the bibliographies of retrieved articles and conference proceedings to obtain additional citations and references. We used those articles that address any non-pharmacological interventions on reducing stereotyped and repetitive behaviors in preschool children with autism. Four independent reviewers screened relevant articles for inclusion criteria and assessed the quality of eligible articles with CONSORT checklist. Results: In our search, 664 relevant articles were found. After removing duplicates and screening based on title, abstract, and full text, 15 high quality studies were finally included in data analyses. The included articles were published from 1987 to 2013. Three studies were designed as A-B, two as A-B-A and reminders as A-B-A-B. The data and results of 3 clinical trials were synthesized; two of them were parallel randomized clinical trial and another one was designed as cross-over. Interventions were completely heterogeneous in case studies, including non-contingent auditory stimulation, response interruption and redirection, teaching the children to request assistance on the difficult tasks, family-implemented treatment for behavioral inflexibility with treatment approach, vocal or motor response interruption and redirection, brushing, water mist treatment, exposure response prevention, tangible reinforcement or social reinforcement, and music. Interventions in clinical trials included touch therapy, kata techniques training program, and aerobic exercise. Conclusions: The results of our review indicate that different kinds of non-pharmacological interventions can

Continuous Video Modeling to Assist with Completion of Multi-Step Home Living Tasks by Young Adults with Moderate Intellectual Disability

Science.gov (United States)

Mechling, Linda C.; Ayres, Kevin M.; Bryant, Kathryn J.; Foster, Ashley L.

2014-01-01

The current study evaluated a relatively new video-based procedure, continuous video modeling (CVM), to teach multi-step cleaning tasks to high school students with moderate intellectual disability. CVM in contrast to video modeling and video prompting allows repetition of the video model (looping) as many times as needed while the user completes…

Exploration of verbal repetition in people with dementia using an online symptom-tracking tool.

Science.gov (United States)

Reeve, Emily; Molin, Pierre; Hui, Amaris; Rockwood, Kenneth

2017-06-01

Online tools can be used by people with dementia and their caregivers to self-identify and track troubling symptoms, such as verbal repetition. We aimed to explore verbal repetition behaviors in people with dementia. Participants were recruited via an online resource for people with dementia and their caregivers. Respondents were instructed to complete information about symptoms that are most important to them for tracking over time. In this cross-sectional study, we analyzed data pertaining to individuals with dementia who had at least three symptoms selected for tracking. Of the 3,573 participants who began a user profile, 1,707 fulfilled criteria for analysis. Verbal repetition was identified as a treatment target in 807 respondents (47.3%). Verbal repetition was more frequent in individuals with mild dementia compared to those with moderate and severe dementia (57.2% vs. 36.0% and 39.9%, p < 0.01) and in those with Alzheimer's disease versus other dementias (65.2% vs. 29.7%, p < 0.001). Repetitive questioning was the most frequent type of verbal repetition (90.5% of individuals with verbal repetition). Verbal repetition was most strongly associated with difficulties operating gadgets/appliances (OR 3.65, 95%CI: 2.82-4.72), lack of interest and/or initiative (3.52: 2.84-4.36), misplacing or losing objects (3.25: 2.64-4.01), and lack of attention and/or concentration (2.62: 2.12-3.26). Verbal repetition is a common symptom in people at all stages of dementia but is most commonly targeted for monitoring and treatment effects in its mild stage. Much research is required to further elucidate the underlying mechanisms and the effect of different treatment strategies.

Quantifying repetitive speech in autism spectrum disorders and language impairment.

Science.gov (United States)

van Santen, Jan P H; Sproat, Richard W; Hill, Alison Presmanes

2013-10-01

We report on an automatic technique for quantifying two types of repetitive speech: repetitions of what the child says him/herself (self-repeats) and of what is uttered by an interlocutor (echolalia). We apply this technique to a sample of 111 children between the ages of four and eight: 42 typically developing children (TD), 19 children with specific language impairment (SLI), 25 children with autism spectrum disorders (ASD) plus language impairment (ALI), and 25 children with ASD with normal, non-impaired language (ALN). The results indicate robust differences in echolalia between the TD and ASD groups as a whole (ALN + ALI), and between TD and ALN children. There were no significant differences between ALI and SLI children for echolalia or self-repetitions. The results confirm previous findings that children with ASD repeat the language of others more than other populations of children. On the other hand, self-repetition does not appear to be significantly more frequent in ASD, nor does it matter whether the child's echolalia occurred within one (immediate) or two turns (near-immediate) of the adult's original utterance. Furthermore, non-significant differences between ALN and SLI, between TD and SLI, and between ALI and TD are suggestive that echolalia may not be specific to ALN or to ASD in general. One important innovation of this work is an objective fully automatic technique for assessing the amount of repetition in a transcript of a child's utterances. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.

Adult Word Recognition and Visual Sequential Memory

Science.gov (United States)

Holmes, V. M.

2012-01-01

Two experiments were conducted investigating the role of visual sequential memory skill in the word recognition efficiency of undergraduate university students. Word recognition was assessed in a lexical decision task using regularly and strangely spelt words, and nonwords that were either standard orthographically legal strings or items made from…

Vocabulary learning in primary school children: working memory and long-term memory components.

Science.gov (United States)

Morra, Sergio; Camba, Roberta

2009-10-01

The goal of this study was to investigate which working memory and long-term memory components predict vocabulary learning. We used a nonword learning paradigm in which 8- to 10-year-olds learned picture-nonword pairs. The nonwords varied in length (two vs. four syllables) and phonology (native sounding vs. including one Russian phoneme). Short, phonologically native nonwords were learned best, whereas learning long nonwords leveled off after a few presentation cycles. Linear structural equation analyses showed an influence of three constructs-phonological sensitivity, vocabulary knowledge, and central attentional resources (M capacity)-on nonword learning, but the extent of their contributions depended on specific characteristics of the nonwords to be learned. Phonological sensitivity predicted learning of all nonword types except short native nonwords, vocabulary predicted learning of only short native nonwords, and M capacity predicted learning of short nonwords but not long nonwords. The discussion considers three learning processes-effortful activation of phonological representations, lexical mediation, and passive associative learning-that use different cognitive resources and could be involved in learning different nonword types.

Repetitive Behavior in Rubinstein-Taybi Syndrome: Parallels with Autism Spectrum Phenomenology

Science.gov (United States)

Waite, Jane; Moss, Joanna; Beck, Sarah R.; Richards, Caroline; Nelson, Lisa; Arron, Kate; Burbidge, Cheryl; Berg, Katy; Oliver, Chris

2015-01-01

Syndrome specific repetitive behavior profiles have been described previously. A detailed profile is absent for Rubinstein-Taybi syndrome (RTS). The Repetitive Behaviour Questionnaire and Social Communication Questionnaire were completed for children and adults with RTS (N = 87), Fragile-X (N = 196) and Down (N = 132) syndromes, and individuals…

Conceptual and non-conceptual repetition priming in category exemplar generation: Evidence from bilinguals.

Science.gov (United States)

Francis, Wendy S; Fernandez, Norma P; Bjork, Robert A

2010-10-01

One measure of conceptual implicit memory is repetition priming in the generation of exemplars from a semantic category, but does such priming transfer across languages? That is, do the overlapping conceptual representations for translation equivalents provide a sufficient basis for such priming? In Experiment 1 (N=96) participants carried out a deep encoding task, and priming between languages was statistically reliable, but attenuated, relative to within-language priming. Experiment 2 (N=96) replicated the findings of Experiment 1 and assessed the contributions of conceptual and non-conceptual processes using a levels-of-processing manipulation. Words that underwent shallow encoding exhibited within-language, but not between-language, priming. Priming in shallow conditions cannot therefore be explained by incidental activation of the concept. Instead, part of the within-language priming effect, even under deep-encoding conditions, is due to increased availability of language-specific lemmas or phonological word forms.

Repetitive, small-bore two-stage light gas gun

International Nuclear Information System (INIS)

Combs, S.K.; Foust, C.R.; Fehling, D.T.; Gouge, M.J.; Milora, S.L.

1991-01-01

A repetitive two-stage light gas gun for high-speed pellet injection has been developed at Oak Ridge National Laboratory. In general, applications of the two-stage light gas gun have been limited to only single shots, with a finite time (at least minutes) needed for recovery and preparation for the next shot. The new device overcomes problems associated with repetitive operation, including rapidly evacuating the propellant gases, reloading the gun breech with a new projectile, returning the piston to its initial position, and refilling the first- and second-stage gas volumes to the appropriate pressure levels. In addition, some components are subjected to and must survive severe operating conditions, which include rapid cycling to high pressures and temperatures (up to thousands of bars and thousands of kelvins) and significant mechanical shocks. Small plastic projectiles (4-mm nominal size) and helium gas have been used in the prototype device, which was equipped with a 1-m-long pump tube and a 1-m-long gun barrel, to demonstrate repetitive operation (up to 1 Hz) at relatively high pellet velocities (up to 3000 m/s). The equipment is described, and experimental results are presented. 124 refs., 6 figs., 5 tabs

Automatization Aspects of Dyslexia: Speed Limitations in Word Identification, Sensitivity to Increasing Task Demands, and Orthographic Compensation.

Science.gov (United States)

van der Leij, Aryan; van Daal, Victor H. P.

1999-01-01

Ten students (age 10) with dyslexia were compared to 10 chronological-age controls and 20 reading-age controls. Response latencies of the students with dyslexia were slower when familiar words, letter clusters, and nonwords had to be named. A larger word-frequency effect and larger word-length effect indicate difficulty with increasing task…

Effects of slow repetitive transcranial magnetic stimulation in patients with corticobasal syndrome.

Science.gov (United States)

Civardi, Carlo; Pisano, Fabrizio; Delconte, Carmen; Collini, Alessandra; Monaco, Francesco

2015-06-01

Corticobasal syndrome is characterized by asymmetric cortical sensorimotor dysfunction and parkinsonism; an altered cortical excitability has been reported. We explored with transcranial magnetic stimulation the motor cortical excitability in corticobasal syndrome, and the effects of slow repetitive transcranial magnetic stimulation. With transcranial magnetic stimulation, we studied two corticobasal syndrome patients. We determined bilaterally from the first dorsal interosseous muscle: relaxed threshold, and contralateral and ipsilateral silent period. We also evaluated the contralateral silent period after active/sham slow repetitive transcranial magnetic stimulation on the most affected side. At T0 the silent period was bilaterally short. On the most affected side, active slow repetitive transcranial magnetic stimulation induced a short lasting prolongation of the contralateral silent period. In corticobasal syndrome, transcranial magnetic stimulation showed a reduction cortical inhibitory phenomenon potentially reversed transiently by slow repetitive transcranial magnetic stimulation.

Sustainment of spherical tokamak by means of repetitive injection of compact torus plasma

International Nuclear Information System (INIS)

Shimamura, Shin; Matsura, Ken; Takahashi, Tsutomu; Nogi, Yasuyuki

2000-01-01

Sustainment of spherical tokamak (S.T.) has been studied. A compact torus (C.T.) plasma was injected into confinement region by magnetized coaxial gun. For start-up and sustainment of large main spherical tokamak, single pulsed injection of small C.T. is not sufficient in many cases. C.T.plasma injection of high repetition rate is required. For this purpose magnetized coaxial gun was driven with high repetition rate current. The first injected C.T. plasma could start-up S.T. without other help. The repetitive C.T. injection grew and sustained the S.T. plasma. A CCD camera with fast gated image intensifier took a cross sectional view of S.T. during the repetitive C.T. injection. (author)

PCR amplification of repetitive sequences as a possible approach in relative species quantification

DEFF Research Database (Denmark)

Ballin, Nicolai Zederkopff; Vogensen, Finn Kvist; Karlsson, Anders H

2012-01-01

Abstract Both relative and absolute quantifications are possible in species quantification when single copy genomic DNA is used. However, amplification of single copy genomic DNA does not allow a limit of detection as low as one obtained from amplification of repetitive sequences. Amplification...... of repetitive sequences is therefore frequently used in absolute quantification but problems occur in relative quantification as the number of repetitive sequences is unknown. A promising approach was developed where data from amplification of repetitive sequences were used in relative quantification of species...... to relatively quantify the amount of chicken DNA in a binary mixture of chicken DNA and pig DNA. However, the designed PCR primers lack the specificity required for regulatory species control....

Design and implementation of fast charging circuit for repetitive compact torus injector

International Nuclear Information System (INIS)

Onchi, T.; McColl, D.; Dreval, M.; Wolfe, S.; Xiao, C.; Hirose, A.

2014-01-01

A novel circuit for compact torus (CT) injector operated at high repetition rates has been developed. The core technology adopted in the present work is to charge a large storage capacitor bank and quickly charge the CT capacitor bank through a stack of insulated-gate bipolar transistors (IGBTs). A system consisting of IGBTs and slow banks for the repetitive operation has been developed and installed for each discharge circuit of the University of Saskatchewan Compact Torus Injector (USCTI). A repetition rate up to 1.7 Hz and a burst of 8 CTs have been achieved

Universal data compression and repetition times

NARCIS (Netherlands)

Willems, Frans M J

1989-01-01

A new universal data compression algorithm is described. This algorithm encodes L source symbols at a time. For the class of binary stationary sources, its rate does not exceed [formula omitted] [formula omitted] bits per source symbol. In our analysis, a property of repetition times turns out to be

High-repetition-rate hydrogen chamber: Preliminary studies; Chambre a hydrogene a haut taux de repetition: Etudes preliminaires

Energy Technology Data Exchange (ETDEWEB)

NONE

1967-01-01

This report is a conclusion to the tests realised with an experimental bubbles chamber in view to study the possibilities to increase the repetition rate. The more important parameters (the evolution of the bubbles, the expansion system) are considered in a theoretical way. Then the hardware is described. To end, experimental results are compared with the first evaluations. The calculations and the experimentation are against an oscillation system for the expansion. A system with a locking is to he considered. (authors) [French] Ce rapport est une conclusion aux essais realises avec une chambre a bulles experimentale en vue d'etudier les possibilites d'accroitre les taux de repetition. Les parametres les plus importants (evolution des bulles, mecanique de la detente) sont etudies par voie theorique. Puis l'appareillage est decrit. Enfin, les resultats experimentaux sont compares aux evaluations donnees au debut. Ces calculs et cette experimentation ne sont pas en faveur d'un systeme oscillant pour la detente et il faut envisager un systeme avec verrouillage. (auteurs)

Variable training does not lead to better motor learning compared to repetitive training in children with and without DCD when exposed to active video games.

Science.gov (United States)

Bonney, Emmanuel; Jelsma, Dorothee; Ferguson, Gillian; Smits-Engelsman, Bouwien

2017-03-01

Little is known about the influence of practice schedules on motor learning and skills transfer in children with and without developmental coordination disorder (DCD). Understanding how practice schedules affect motor learning is necessary for motor skills development and rehabilitation. The study investigated whether active video games (exergames) training delivered under variable practice led to better learning and transfer than repetitive practice. 111 children aged 6-10 years (M=8.0, SD=1.0) with no active exergaming experience were randomized to receive exergames training delivered under variable (Variable Game Group (VGG), n=56) or repetitive practice schedule (Repetitive Game Group (RGG), n=55). Half the participants were identified as DCD using the DSM-5 criteria, while the rest were typically developing (TD), age-matched children. Both groups participated in two 20min sessions per week for 5 weeks. Both participant groups (TD and DCD) improved equally well on game performance. There was no significant difference in positive transfer to balance tasks between practice schedules (Repetitive and Variable) and participant groups (TD and DCD). Children with and without DCD learn balance skills quite well when exposed to exergames. Gains in learning and transfer are similar regardless of the form of practice schedule employed. This is the first paper to compare the effect of practice schedules on learning in children with DCD and those with typical development. No differences in motor learning were found between repetitive and variable practice schedules. When children with and without DCD spend the same amount of time on exergames, they do not show any differences in acquisition of motor skills. Transfer of motor skills is similar in children with and without DCD regardless of differences in practice schedules. Copyright © 2017 Elsevier Ltd. All rights reserved.

Delay or deficit? Spelling processes in children with specific language impairment.

Science.gov (United States)

Larkin, Rebecca F; Williams, Gareth J; Blaggan, Samarita

2013-01-01

Few studies have explored the phonological, morphological and orthographic spellings skills of children with specific language impairment (SLI) simultaneously. Fifteen children with SLI (mean age=113.07 months, SD=8.61) completed language and spelling tasks alongside chronological-age controls and spelling-age controls. While the children with SLI showed a deficit in phonological spelling, they performed comparably to spelling-age controls on morphological spelling skills, and there were no differences between the three groups in producing orthographically legal spellings. The results also highlighted the potential importance of adequate non-word repetition skills in relation to effective spelling skills, and demonstrated that not all children with spoken language impairments show marked spelling difficulties. Findings are discussed in relation to theory, educational assessment and practice. As a result of this activity, readers will describe components of spoken language that predict children's morphological and phonological spelling performance. As a result of this activity, readers will describe how the spelling skills of children with SLI compare to age-matched and spelling age-matched control children. Readers will be able to interpret the variability in spelling performance seen in children with SLI. Copyright © 2013 Elsevier Inc. All rights reserved.

Iodine laser of high efficiency and fast repetition rate

Energy Technology Data Exchange (ETDEWEB)

Hohla, K; Witte, K J

1976-07-01

The scaling laws of an iodine laser of high efficiency and fast repetition rate are reported. The laser is pumped with a new kind of low pressure Hg-UV-lamps which convert 32% of the electrical input in UV-light in the absorption band of the iodine laser and which can be fired up to 100 Hz. Details of a 10 kJ/1 nsec system as dimensions, energy density, repetition rate, flow velocity, gas composition and gas pressure and the overall efficiency are given which is expected to be about 2%.

The Role of Antibody in Korean Word Recognition

Science.gov (United States)

Lee, Chang Hwan; Lee, Yoonhyoung; Kim, Kyungil

2010-01-01

A subsyllabic phonological unit, the antibody, has received little attention as a potential fundamental processing unit in word recognition. The psychological reality of the antibody in Korean recognition was investigated by looking at the performance of subjects presented with nonwords and words in the lexical decision task. In Experiment 1, the…

Identifying language impairment in bilingual children in France and in Germany.

Science.gov (United States)

Tuller, Laurice; Hamann, Cornelia; Chilla, Solveig; Ferré, Sandrine; Morin, Eléonore; Prevost, Philippe; Dos Santos, Christophe; Abed Ibrahim, Lina; Zebib, Racha

2018-05-23

The detection of specific language impairment (SLI) in children growing up bilingually presents particular challenges for clinicians. Non-word repetition (NWR) and sentence repetition (SR) tasks have proven to be the most accurate diagnostic tools for monolingual populations, raising the question of the extent of their usefulness in different bilingual populations. To determine the diagnostic accuracy of NWR and SR tasks that incorporate phonological/syntactic complexity as discussed in recent linguistic theory. The tasks were developed as part of the Language Impairment Testing in Multilingual Settings (LITMUS) toolkit, in two different national settings, France and Germany, and investigated children with three different home languages: Arabic, Portuguese and Turkish. NWR and SR tasks developed in parallel were administered to 151 bilingual children, aged 5;6-8;11, in France and in Germany, to 64 children in speech-language therapy (SLT) and to 87 children not in SLT, whose first language (L1) was Arabic, Portuguese or Turkish. Children were also administered standardized language tests in each of their languages to determine likely clinical status (typical development (TD) or SLI), and parents responded to a questionnaire including questions about early and current language use (bilingualism factors) and early language development (risk factors for SLI). Monolingual controls included 47 TD children and 29 children with SLI. Results were subjected to inter-group comparisons, to diagnostic accuracy calculation, and to correlation and multiple regression analyses. In accordance with previous studies, NWR and SR identified SLI in the monolingual children, yielding good to excellent diagnostic accuracy. Diagnostic accuracy in bilingual children was fair to good, generally distinguishing children likely to have SLI from children likely to have TD. Accuracy was necessarily linked to the determination of clinical status, which was based on standardized assessment in each

Heavy-duty high-repetition-rate generators

NARCIS (Netherlands)

Heesch, van E.J.M.; Yan, K.; Pemen, A.J.M.

2002-01-01

We present our results on high-power repetitive pulse sources for continuous operation. Two 1-10-kW systems using advanced spark gap technology and a transmission line transformer have been tested for several hundred hours at a 60-MW pulse level. High reliability and above 90% overall efficiency are

Repetitive low-frequency stimulation reduces epileptiform synchronization in limbic neuronal networks.

Science.gov (United States)

D'Arcangelo, G; Panuccio, G; Tancredi, V; Avoli, M

2005-01-01

Deep-brain electrical or transcranial magnetic stimulation may represent a therapeutic tool for controlling seizures in patients presenting with epileptic disorders resistant to antiepileptic drugs. In keeping with this clinical evidence, we have reported that repetitive electrical stimuli delivered at approximately 1 Hz in mouse hippocampus-entorhinal cortex (EC) slices depress the EC ability to generate ictal activity induced by the application of 4-aminopyridine (4AP) or Mg(2+)-free medium (Barbarosie, M., Avoli, M., 1997. CA3-driven hippocampal-entorhinal loop controls rather than sustains in vitro limbic seizures. J. Neurosci. 17, 9308-9314.). Here, we confirmed a similar control mechanism in rat brain slices analyzed with field potential recordings during 4AP (50 microM) treatment. In addition, we used intrinsic optical signal (IOS) recordings to quantify the intensity and spatial characteristics of this inhibitory influence. IOSs reflect the changes in light transmittance throughout the entire extent of the slice, and are thus reliable markers of limbic network epileptiform synchronization. First, we found that in the presence of 4AP, the IOS increases, induced by a train of electrical stimuli (10 Hz for 1 s) or by recurrent, single-shock stimulation delivered at 0.05 Hz in the deep EC layers, are reduced in intensity and area size by low-frequency (1 Hz), repetitive stimulation of the subiculum; these effects were observed in all limbic areas contained in the slice. Second, by testing the effects induced by repetitive subicular stimulation at 0.2-10 Hz, we identified maximal efficacy when repetitive stimuli are delivered at 1 Hz. Finally, we discovered that similar, but slightly less pronounced, inhibitory effects occur when repetitive stimuli at 1 Hz are delivered in the EC, suggesting that the reduction of IOSs seen during repetitive stimulation is pathway dependent as well as activity dependent. Thus, the activation of limbic networks at low frequency

A direct comparison of spine rotational stiffness and dynamic spine stability during repetitive lifting tasks.

Science.gov (United States)

Graham, Ryan B; Brown, Stephen H M

2012-06-01

Stability of the spinal column is critical to bear loads, allow movement, and at the same time avoid injury and pain. However, there has been a debate in recent years as to how best to define and quantify spine stability, with the outcome being that different methods are used without a clear understanding of how they relate to one another. Therefore, the goal of the present study was to directly compare lumbar spine rotational stiffness, calculated with an EMG-driven biomechanical model, to local dynamic spine stability calculated using Lyapunov analyses of kinematic data, during a series of continuous dynamic lifting challenges. Twelve healthy male subjects performed 30 repetitive lifts under three varying load and three varying rate conditions. With an increase in the load lifted (constant rate) there was a significant increase in mean, maximum, and minimum spine rotational stiffness (pstiffness (pstiffness and a non-significant decrease in local dynamic stability (p>0.05). Weak linear relationships were found for the varying rate conditions (r=-0.02 to -0.27). The results suggest that spine rotational stiffness and local dynamic stability are closely related to one another, as they provided similar information when movement rate was controlled. However, based on the results from the changing lifting rate conditions, it is evident that both models provide unique information and that future research is required to completely understand the relationship between the two models. Using both techniques concurrently may provide the best information regarding the true effects of (in) stability under different loading and movement scenarios, and in comparing healthy and clinical populations. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of short-term training on behavioral learning and skill acquisition during intraoral fine motor task

DEFF Research Database (Denmark)

Kumar, Abhishek; Grigoriadis, Joannis; Trulsson, Mats

2015-01-01

Sensory information from the orofacial mechanoreceptors are used by the nervous system to optimize the positioning of food, determine the force levels, and force vectors involved in biting of food morsels. Moreover, practice resulting from repetition could be a key to learning and acquiring a motor...... movements. Thirty healthy volunteers were asked to intraorally manipulate and split a chocolate candy, into two equal halves. The participants performed three series (with ten 10 trials) of the task before and after a short-term (approximately 30min) training. The accuracy of the split and vertical jaw...... task induces behavior learning, skill acquisition and optimization of jaw movements in terms of better performance and reduction in the duration of jaw movements, during the task. The finding of the present study provides insights on into how humans learn oral motor behaviors or the kind of adaptation...

High repetition rate intense ion beam source

International Nuclear Information System (INIS)

Hammer, D.A.; Glidden, S.C.; Noonan, B.

1992-01-01

This final report describes a ≤ 150kV, 40kA, 100ns high repetition rate pulsed power system and intense ion beam source which is now in operation at Cornell University. Operation of the Magnetically-controlled Anode Plasma (MAP) ion diode at > 100Hz (burst mode for up to 10 pulse bursts) provides an initial look at repetition rate limitations of both the ion diode and beam diagnostics. The pulsed power systems are capable of ≥ 1kHz operation (up to 10 pulse bursts), but ion diode operation was limited to ∼100Hz because of diagnostic limitations. By varying MAP diode operating parameters, ion beams can be extracted at a few 10s of keV or at up to 150keV, the corresponding accelerating gap impedance ranging from about 1Ω to about 10Ω. The ability to make hundreds of test pulses per day at an average repetition rate of about 2 pulses per minute permits statistical analysis of diode operation as a function of various parameters. Most diode components have now survived more than 10 4 pulses, and the design and construction of the various pulsed power components of the MAP diode which have enabled us to reach this point are discussed. A high speed data acquisition system and companion analysis software capable of acquiring pulse data at 1ms intervals (in bursts of up to 10 pulses) and processing it in ≤ min is described

MIMICRY, DIFFERENCE AND REPETITION

Directory of Open Access Journals (Sweden)

Marcelo Mendes de Souza

2008-07-01

Full Text Available This article addresses Homi K. Bhabha’s concept of mimicry in a broader context, other than that of cultural studies and post-colonial studies, bringing together other concepts, such as that of Gilles Deleuze in Difference and repetition, among other texts, and other names, such as Silviano Santiago, Jorge Luís Borges, Franz Kafka and Giorgio Agamben. As a partial conclusion, the article intends to oppose Bhabha’s freudian-marxist view to Five propositions on Psychoanalysis (1973, Gilles Deleuze’s text about Psychoanalysis published right after his book The Anti-Oedipus.

Neurobehavioural Correlates of Abnormal Repetitive Behaviour

Directory of Open Access Journals (Sweden)

R. A. Ford

1991-01-01

Full Text Available Conditions in which echolalia and echopraxia occur are reviewed, followed by an attempt to elicit possible mechanisms of these phenomena. A brief description of stereotypical and perseverative behaviour and obsessional phenomena is given. It is suggested that abnormal repetitive behaviour may occur partly as a result of central dopaminergic dysfunction.

Longer repetition duration increases muscle activation and blood lactate response in matched resistance training protocols

Directory of Open Access Journals (Sweden)

Hugo Cesar Martins-Costa

2016-03-01

Full Text Available Abstract This study analyzed the effect of different repetition durations on electromyographic and blood lactate responses of the bench press exercise. Fifteen recreationally trained male volunteers completed two training protocols, matched for intensity (% one-repetition maximum; 1RM, number of sets, number of repetitions, and rest intervals. One of the protocols was performed with a repetition duration of 4 s (2 s concentric: 2 s eccentric; 2:2 protocol, whereas the second protocol had a repetition duration of 6 s (2 s concentric: 4 s eccentric; 2:4 protocol. The results showed higher normalized integrated electromyography (pectoralis major and triceps brachii for the 2:4 protocol. Blood lactate concentration was also higher in the 2:4 protocol across all sets. These results show that adding 2 s to the eccentric action in matched training protocols increases muscle activation and blood lactate response, which reinforces the notion that increasing repetition duration is an alternative load progression in resistance training.

Repetitive element transcripts are elevated in the brain of C9orf72 ALS/FTLD patients.

Science.gov (United States)

Prudencio, Mercedes; Gonzales, Patrick K; Cook, Casey N; Gendron, Tania F; Daughrity, Lillian M; Song, Yuping; Ebbert, Mark T W; van Blitterswijk, Marka; Zhang, Yong-Jie; Jansen-West, Karen; Baker, Matthew C; DeTure, Michael; Rademakers, Rosa; Boylan, Kevin B; Dickson, Dennis W; Petrucelli, Leonard; Link, Christopher D

2017-09-01

Significant transcriptome alterations are detected in the brain of patients with amyotrophic lateral sclerosis (ALS), including carriers of the C9orf72 repeat expansion and C9orf72-negative sporadic cases. Recently, the expression of repetitive element transcripts has been associated with toxicity and, while increased repetitive element expression has been observed in several neurodegenerative diseases, little is known about their contribution to ALS. To assess whether aberrant expression of repetitive element sequences are observed in ALS, we analysed RNA sequencing data from C9orf72-positive and sporadic ALS cases, as well as healthy controls. Transcripts from multiple classes and subclasses of repetitive elements (LINEs, endogenous retroviruses, DNA transposons, simple repeats, etc.) were significantly increased in the frontal cortex of C9orf72 ALS patients. A large collection of patient samples, representing both C9orf72 positive and negative ALS, ALS/FTLD, and FTLD cases, was used to validate the levels of several repetitive element transcripts. These analyses confirmed that repetitive element expression was significantly increased in C9orf72-positive compared to C9orf72-negative or control cases. While previous studies suggest an important link between TDP-43 and repetitive element biology, our data indicate that TDP-43 pathology alone is insufficient to account for the observed changes in repetitive elements in ALS/FTLD. Instead, we found that repetitive element expression positively correlated with RNA polymerase II activity in postmortem brain, and pharmacologic modulation of RNA polymerase II activity altered repetitive element expression in vitro. We conclude that increased RNA polymerase II activity in ALS/FTLD may lead to increased repetitive element transcript expression, a novel pathological feature of ALS/FTLD. © The Author 2017. Published by Oxford University Press.

High-speed repetitive pellet injector prototype for magnetic confinement fusion devices

International Nuclear Information System (INIS)

Frattolillo, A.; Gasparotto, M.; Migliori, S.; Angelone, G.; Baldarelli, M.; Scaramuzzi, F.; Ronci, G.; Reggiori, A.; Riva, G.; Carlevaro, R.; Daminelli, G.B.

1992-01-01

The design of a test facility aimed at demonstrating the feasibility of high-speed repetitive acceleration of solid D 2 pellets for fusion applications, developed in a collaboration between Oak Ridge National Laboratory and ENEA Frascati, is presented. The results of tests performed at the CNPM/CNR on the piston wear in a repetitively operating two-stage gun are also reported

Inhibitory processes for critical situations – The role of n-2 task repetition costs in human multitasking situations

Directory of Open Access Journals (Sweden)

Miriam eGade

2012-05-01

Full Text Available The human cognitive system is equipped with various processes for dealing with everyday challenges. One of such processes is the inhibition of currently irrelevant goals or mental task sets, which can be seen as a response to the critical event of information overflow in the cognitive system and the cognitive system’s inability to keep track of ongoing demands. In two experiments, we investigate the flexibility of the inhibitory process by inserting rare non-critical events (25% of all trials, operationalized as univalent stimuli (i.e., unambiguous stimuli that call for only one specific task in a multitasking context, and by introducing the possibility to prepare for an upcoming task (Experiment 2. We found that the inhibitory process is not influenced by a cue informing subjects about the upcoming occurrence of a univalent stimulus. However, the introduction of univalent stimuli allowed preparatory processes to modify the impact of the inhibitory process. Therefore, our results suggest that inhibitory processes are engaged in a rather global manner, not taking into account variations in stimulus valence, which we took as operationalization of critical, conflict-inducing events in the ongoing stream of information processing. However, rare uncritical events, such as univalent stimuli that do not cause conflict and interference in the processing stream, appear to alter the way the cognitive system can take advantage of preparatory processes.

Widespread Chromatin Accessibility at Repetitive Elements Links Stem Cells with Human Cancer

Directory of Open Access Journals (Sweden)

Nicholas C. Gomez

2016-11-01

Full Text Available Chromatin regulation is critical for differentiation and disease. However, features linking the chromatin environment of stem cells with disease remain largely unknown. We explored chromatin accessibility in embryonic and multipotent stem cells and unexpectedly identified widespread chromatin accessibility at repetitive elements. Integrating genomic and biochemical approaches, we demonstrate that these sites of increased accessibility are associated with well-positioned nucleosomes marked by distinct histone modifications. Differentiation is accompanied by chromatin remodeling at repetitive elements associated with altered expression of genes in relevant developmental pathways. Remarkably, we found that the chromatin environment of Ewing sarcoma, a mesenchymally derived tumor, is shared with primary mesenchymal stem cells (MSCs. Accessibility at repetitive elements in MSCs offers a permissive environment that is exploited by the critical oncogene responsible for this cancer. Our data demonstrate that stem cells harbor a unique chromatin landscape characterized by accessibility at repetitive elements, a feature associated with differentiation and oncogenesis.

Tactile Ranschburg effects: facilitation and inhibitory repetition effects analogous to verbal memory.

Science.gov (United States)

Roe, Daisy; Miles, Christopher; Johnson, Andrew J

2017-07-01

The present paper examines the effect of within-sequence item repetitions in tactile order memory. Employing an immediate serial recall procedure, participants reconstructed a six-item sequence tapped upon their fingers by moving those fingers in the order of original stimulation. In Experiment 1a, within-sequence repetition of an item separated by two-intervening items resulted in a significant reduction in recall accuracy for that repeated item (i.e., the Ranschburg effect). In Experiment 1b, within-sequence repetition of an adjacent item resulted in significant recall facilitation for that repeated item. These effects mirror those reported for verbal stimuli (e.g., Henson, 1998a . Item repetition in short-term memory: Ranschburg repeated. Journal of Experimental Psychology: Learning, Memory, and Cognition, 24(5), 1162-1181. doi:doi.org/10.1037/0278-7393.24.5.1162). These data are the first to demonstrate the Ranschburg effect with non-verbal stimuli and suggest further cross-modal similarities in order memory.

Extraction of repetitive transients with frequency domain multipoint kurtosis for bearing fault diagnosis

Science.gov (United States)

Liao, Yuhe; Sun, Peng; Wang, Baoxiang; Qu, Lei

2018-05-01

The appearance of repetitive transients in a vibration signal is one typical feature of faulty rolling element bearings. However, accurate extraction of these fault-related characteristic components has always been a challenging task, especially when there is interference from large amplitude impulsive noises. A frequency domain multipoint kurtosis (FDMK)-based fault diagnosis method is proposed in this paper. The multipoint kurtosis is redefined in the frequency domain and the computational accuracy is improved. An envelope autocorrelation function is also presented to estimate the fault characteristic frequency, which is used to set the frequency hunting zone of the FDMK. Then, the FDMK, instead of kurtosis, is utilized to generate a fast kurtogram and only the optimal band with maximum FDMK value is selected for envelope analysis. Negative interference from both large amplitude impulsive noise and shaft rotational speed related harmonic components are therefore greatly reduced. The analysis results of simulation and experimental data verify the capability and feasibility of this FDMK-based method

ReRep: Computational detection of repetitive sequences in genome survey sequences (GSS

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Alves-Ferreira Marcelo

2008-09-01

Full Text Available Abstract Background Genome survey sequences (GSS offer a preliminary global view of a genome since, unlike ESTs, they cover coding as well as non-coding DNA and include repetitive regions of the genome. A more precise estimation of the nature, quantity and variability of repetitive sequences very early in a genome sequencing project is of considerable importance, as such data strongly influence the estimation of genome coverage, library quality and progress in scaffold construction. Also, the elimination of repetitive sequences from the initial assembly process is important to avoid errors and unnecessary complexity. Repetitive sequences are also of interest in a variety of other studies, for instance as molecular markers. Results We designed and implemented a straightforward pipeline called ReRep, which combines bioinformatics tools for identifying repetitive structures in a GSS dataset. In a case study, we first applied the pipeline to a set of 970 GSSs, sequenced in our laboratory from the human pathogen Leishmania braziliensis, the causative agent of leishmaniosis, an important public health problem in Brazil. We also verified the applicability of ReRep to new sequencing technologies using a set of 454-reads of an Escheria coli. The behaviour of several parameters in the algorithm is evaluated and suggestions are made for tuning of the analysis. Conclusion The ReRep approach for identification of repetitive elements in GSS datasets proved to be straightforward and efficient. Several potential repetitive sequences were found in a L. braziliensis GSS dataset generated in our laboratory, and further validated by the analysis of a more complete genomic dataset from the EMBL and Sanger Centre databases. ReRep also identified most of the E. coli K12 repeats prior to assembly in an example dataset obtained by automated sequencing using 454 technology. The parameters controlling the algorithm behaved consistently and may be tuned to the properties

Don't Throw out the Baby with the Bathwater: Verbal Repetition, Mnemonics, and Active Learning