WorldWideScience

Sample records for single word decoding

  1. Word Processing in Dyslexics: An Automatic Decoding Deficit?

    Science.gov (United States)

    Yap, Regina; Van Der Leu, Aryan

    1993-01-01

    Compares dyslexic children with normal readers on measures of phonological decoding and automatic word processing. Finds that dyslexics have a deficit in automatic phonological decoding skills. Discusses results within the framework of the phonological deficit and the automatization deficit hypotheses. (RS)

  2. Individual Differences in the Cognitive Processes of Reading: I. Word Decoding.

    Science.gov (United States)

    Stanovich, Keith E.

    1982-01-01

    The importance of word decoding in accounting for individual differences in reading comprehension is discussed. Research on individual differences in the cognitive processes that mediate word decoding is reviewed. (Author)

  3. Decoding speech perception from single cell activity in humans.

    Science.gov (United States)

    Ossmy, Ori; Fried, Itzhak; Mukamel, Roy

    2015-08-15

    Deciphering the content of continuous speech is a challenging task performed daily by the human brain. Here, we tested whether activity of single cells in auditory cortex could be used to support such a task. We recorded neural activity from auditory cortex of two neurosurgical patients while presented with a short video segment containing speech. Population spiking activity (~20 cells per patient) allowed detection of word onset and decoding the identity of perceived words with significantly high accuracy levels. Oscillation phase of local field potentials (8-12Hz) also allowed decoding word identity although with lower accuracy levels. Our results provide evidence that the spiking activity of a relatively small population of cells in human primary auditory cortex contains significant information for classification of words in ongoing speech. Given previous evidence for overlapping neural representation during speech perception and production, this may have implications for developing brain-machine interfaces for patients with deficits in speech production. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Predicting word decoding and word spelling development in children with Specific Language Impairment.

    Science.gov (United States)

    van Weerdenburg, Marjolijn; Verhoeven, Ludo; Bosman, Anna; van Balkom, Hans

    2011-01-01

    This longitudinal investigation on Dutch children with Specific Language Impairment (SLI) aimed at determining the predictive value of statistically uncorrelated language proficiencies on later reading and spelling skills in Dutch. Language abilities, tested with an extensive test battery at the onset of formal reading instruction, were represented by four statistically uncorrelated factors: lexical-semantic abilities, auditory perception, verbal-sequential processing, and speech production. All factors contributed significantly to the prediction of word reading and spelling development seven months later. Verbal-sequential processing was the strongest predictor for both word decoding and spelling. Furthermore, autoregression effects of word decoding and spelling were strong and verbal-sequential processing had predictive value on word spelling nineteen months later when pre-existing spelling abilities were accounted for. Children with SLI and normal literacy skills performed better on most of the language and language-related measures than children with SLI and poor literacy skills. As a result of this activity, readers will describe four language domains that are related to later literacy skills in children with Specific Language Impairment (SLI). As a result of this activity, readers will recognize the predictive value of each of these language domains and the important role of verbal-sequential processing in learning to decode and writing words for children with SLI. As a result of this activity, readers will recall the differences in language proficiencies between children with SLI who develop normal literacy skills and those who encounter literacy problems. Copyright © 2010 Elsevier Inc. All rights reserved.

  5. Early Word Decoding Ability as a Longitudinal Predictor of Academic Performance

    Science.gov (United States)

    Nordström, Thomas; Jacobson, Christer; Söderberg, Pernilla

    2016-01-01

    This study, using a longitudinal design with a Swedish cohort of young readers, investigates if children's early word decoding ability in second grade can predict later academic performance. In an effort to estimate the unique effect of early word decoding (grade 2) with academic performance (grade 9), gender and non-verbal cognitive ability were…

  6. Word Decoding Development during Phonics Instruction in Children at Risk for Dyslexia.

    Science.gov (United States)

    Schaars, Moniek M H; Segers, Eliane; Verhoeven, Ludo

    2017-05-01

    In the present study, we examined the early word decoding development of 73 children at genetic risk of dyslexia and 73 matched controls. We conducted monthly curriculum-embedded word decoding measures during the first 5 months of phonics-based reading instruction followed by standardized word decoding measures halfway and by the end of first grade. In kindergarten, vocabulary, phonological awareness, lexical retrieval, and verbal and visual short-term memory were assessed. The results showed that the children at risk were less skilled in phonemic awareness in kindergarten. During the first 5 months of reading instruction, children at risk were less efficient in word decoding and the discrepancy increased over the months. In subsequent months, the discrepancy prevailed for simple words but increased for more complex words. Phonemic awareness and lexical retrieval predicted the reading development in children at risk and controls to the same extent. It is concluded that children at risk are behind their typical peers in word decoding development starting from the very beginning. Furthermore, it is concluded that the disadvantage increased during phonics instruction and that the same predictors underlie the development of word decoding in the two groups of children. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  7. From spelling pronunciation to lexical access: a second step in word decoding?

    NARCIS (Netherlands)

    Elbro, C.; de Jong, P.F.; Houter, D.; Nielsen, A.-M.

    2012-01-01

    There is a gap between "w..aa..sss" and "woz" (was). This is a gap between the output from a phonological recoding of a word and its lexical pronunciation. We suggest that ease of recognition of words from spelling pronunciations (like "w..aa..sss") contributes independent variance to word decoding

  8. Euclidean Geometry Codes, minimum weight words and decodable error-patterns using bit-flipping

    DEFF Research Database (Denmark)

    Høholdt, Tom; Justesen, Jørn; Jonsson, Bergtor

    2005-01-01

    We determine the number of minimum wigth words in a class of Euclidean Geometry codes and link the performance of the bit-flipping decoding algorithm to the geometry of the error patterns.......We determine the number of minimum wigth words in a class of Euclidean Geometry codes and link the performance of the bit-flipping decoding algorithm to the geometry of the error patterns....

  9. Word-decoding as a function of temporal processing in the visual system.

    Directory of Open Access Journals (Sweden)

    Steven R Holloway

    Full Text Available This study explored the relation between visual processing and word-decoding ability in a normal reading population. Forty participants were recruited at Arizona State University. Flicker fusion thresholds were assessed with an optical chopper using the method of limits by a 1-deg diameter green (543 nm test field. Word decoding was measured using reading-word and nonsense-word decoding tests. A non-linguistic decoding measure was obtained using a computer program that consisted of Landolt C targets randomly presented in four cardinal orientations, at 3-radial distances from a focus point, for eight compass points, in a circular pattern. Participants responded by pressing the arrow key on the keyboard that matched the direction the target was facing. The results show a strong correlation between critical flicker fusion thresholds and scores on the reading-word, nonsense-word, and non-linguistic decoding measures. The data suggests that the functional elements of the visual system involved with temporal modulation and spatial processing may affect the ease with which people read.

  10. Mathematics is differentially related to reading comprehension and word decoding: Evidence from a genetically-sensitive design

    Science.gov (United States)

    Harlaar, Nicole; Kovas, Yulia; Dale, Philip S.; Petrill, Stephen A.; Plomin, Robert

    2013-01-01

    Although evidence suggests that individual differences in reading and mathematics skills are correlated, this relationship has typically only been studied in relation to word decoding or global measures of reading. It is unclear whether mathematics is differentially related to word decoding and reading comprehension. The current study examined these relationships at both a phenotypic and etiological level in a population-based cohort of 5162 twin pairs at age 12. Multivariate genetic analyses of latent phenotypic factors of mathematics, word decoding and reading comprehension revealed substantial genetic and shared environmental correlations among all three domains. However, the phenotypic and genetic correlations between mathematics and reading comprehension were significantly greater than between mathematics and word decoding. Independent of mathematics, there was also evidence for genetic and nonshared environmental links between word decoding and reading comprehension. These findings indicate that word decoding and reading comprehension have partly distinct relationships with mathematics in the middle school years. PMID:24319294

  11. Exploring Differential Effects across Two Decoding Treatments on Item-Level Transfer in Children with Significant Word Reading Difficulties: A New Approach for Testing Intervention Elements

    Science.gov (United States)

    Steacy, Laura M.; Elleman, Amy M.; Lovett, Maureen W.; Compton, Donald L.

    2016-01-01

    In English, gains in decoding skill do not map directly onto increases in word reading. However, beyond the Self-Teaching Hypothesis, little is known about the transfer of decoding skills to word reading. In this study, we offer a new approach to testing specific decoding elements on transfer to word reading. To illustrate, we modeled word-reading…

  12. Pathways to Word Reading and Decoding: The Roles of Automaticity and Accuracy

    Science.gov (United States)

    Cummings, Kelli D.; Dewey, Elizabeth N.; Latimer, Rachel J.; Good, Rolland H., III

    2011-01-01

    The purpose of this article is to describe the relationship of initial skill and rate of progress on a measure of the alphabetic principle, Nonsense Word Fluency (NWF), to first-grade reading outcomes as measured by Oral Reading Fluency (ORF). In addition, we describe a scoring approach to NWF where the predominant decoding strategy (i.e.,…

  13. Enhancing decoding efficiency in poor readers via a word identification game

    NARCIS (Netherlands)

    Gorp, K. van; Segers, P.C.J.; Verhoeven, L.T.W.

    2017-01-01

    The effects of a word identification game aimed at enhancing decoding efficiency in poor readers were tested. Following a pretest-posttest-retention design with a waiting control group, 62 poor-reading Dutch second graders received a five-hour tablet intervention across a period of five weeks.

  14. Word decoding development in incremental phonics instruction in a transparent orthography

    NARCIS (Netherlands)

    Schaars, M.M.H.; Segers, P.C.J.; Verhoeven, L.T.W.

    2017-01-01

    The present longitudinal study aimed to investigate the development of word decoding skills during incremental phonics instruction in Dutch as a transparent orthography. A representative sample of 973 Dutch children in the first grade (M age  = 6;1, SD = 0;5) was exposed to incremental subsets of

  15. The Effects of Word Box Instruction on Acquisition, Generalization, and Maintenance of Decoding and Spelling Skills for First Graders

    Science.gov (United States)

    Alber-Morgan, Sheila R.; Joseph, Laurice M.; Kanotz, Brittany; Rouse, Christina A.; Sawyer, Mary R.

    2016-01-01

    This study examined the effects of implementing word boxes as a supplemental instruction method on the acquisition, maintenance, and generalization of word identification and spelling. Word box intervention consists of using manipulatives to learn phonological decoding skills. The participants were three African-American urban first graders…

  16. The attentional blink is related to phonemic decoding, but not sight-word recognition, in typically reading adults.

    Science.gov (United States)

    Tyson-Parry, Maree M; Sailah, Jessica; Boyes, Mark E; Badcock, Nicholas A

    2015-10-01

    This research investigated the relationship between the attentional blink (AB) and reading in typical adults. The AB is a deficit in the processing of the second of two rapidly presented targets when it occurs in close temporal proximity to the first target. Specifically, this experiment examined whether the AB was related to both phonological and sight-word reading abilities, and whether the relationship was mediated by accuracy on a single-target rapid serial visual processing task (single-target accuracy). Undergraduate university students completed a battery of tests measuring reading ability, non-verbal intelligence, and rapid automatised naming, in addition to rapid serial visual presentation tasks in which they were required to identify either two (AB task) or one (single target task) target/s (outlined shapes: circle, square, diamond, cross, and triangle) in a stream of random-dot distractors. The duration of the AB was related to phonological reading (n=41, β=-0.43): participants who exhibited longer ABs had poorer phonemic decoding skills. The AB was not related to sight-word reading. Single-target accuracy did not mediate the relationship between the AB and reading, but was significantly related to AB depth (non-linear fit, R(2)=.50): depth reflects the maximal cost in T2 reporting accuracy in the AB. The differential relationship between the AB and phonological versus sight-word reading implicates common resources used for phonemic decoding and target consolidation, which may be involved in cognitive control. The relationship between single-target accuracy and the AB is discussed in terms of cognitive preparation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. EEG decoding of spoken words in bilingual listeners: from words to language invariant semantic-conceptual representations

    Directory of Open Access Journals (Sweden)

    João Mendonça Correia

    2015-02-01

    Full Text Available Spoken word recognition and production require fast transformations between acoustic, phonological and conceptual neural representations. Bilinguals perform these transformations in native and non-native languages, deriving unified semantic concepts from equivalent, but acoustically different words. Here we exploit this capacity of bilinguals to investigate input invariant semantic representations in the brain. We acquired EEG data while Dutch subjects, highly proficient in English listened to four monosyllabic and acoustically distinct animal words in both languages (e.g. ‘paard’-‘horse’. Multivariate pattern analysis (MVPA was applied to identify EEG response patterns that discriminate between individual words within one language (within-language discrimination and generalize meaning across two languages (across-language generalization. Furthermore, employing two EEG feature selection approaches, we assessed the contribution of temporal and oscillatory EEG features to our classification results. MVPA revealed that within-language discrimination was possible in a broad time-window (~50-620 ms after word onset probably reflecting acoustic-phonetic and semantic-conceptual differences between the words. Most interestingly, significant across-language generalization was possible around 550-600 ms, suggesting the activation of common semantic-conceptual representations from the Dutch and English nouns. Both types of classification, showed a strong contribution of oscillations below 12 Hz, indicating the importance of low frequency oscillations in the neural representation of individual words and concepts. This study demonstrates the feasibility of MVPA to decode individual spoken words from EEG responses and to assess the spectro-temporal dynamics of their language invariant semantic-conceptual representations. We discuss how this method and results could be relevant to track the neural mechanisms underlying conceptual encoding in

  18. Try a Little Bit of Teaching: A Dynamic Assessment of Word Decoding as a Kindergarten Predictor of Word Reading Difficulties at the End of Grade 1

    Science.gov (United States)

    Gellert, Anna S.; Elbro, Carsten

    2017-01-01

    The present study examined the construct and predictive validity of a dynamic test of decoding. In theory, a dynamic test provides a direct measure of potential for learning. In this study, children were taught 3 novel letters and how to blend the sounds of those into new words, then they were tested on different words comprising the 3 letters.…

  19. Importance of Speech Production for Phonological Awareness and Word Decoding: The Case of Children with Cerebral Palsy

    Science.gov (United States)

    Peeters, Marieke; Verhoeven, Ludo; de Moor, Jan; van Balkom, Hans

    2009-01-01

    The goal of this longitudinal study was to investigate the precursors of early reading development in 52 children with cerebral palsy at kindergarten level in comparison to 65 children without disabilities. Word Decoding was measured to investigate early reading skills, while Phonological Awareness, Phonological Short-term Memory (STM), Speech…

  20. Importance of speech production for phonological awareness and word decoding: The case of children with cerebral palsy

    NARCIS (Netherlands)

    Peeters, M.H.J.; Verhoeven, L.T.W.; Moor, J.M.H. de; Balkom, L.J.M. van

    2009-01-01

    The goal of this longitudinal study was to investigate the precursors of early reading development in 52 children with cerebral palsy at kindergarten level in comparison to 65 children without disabilities. Word Decoding was measured to investigate early reading skills, while Phonological Awareness,

  1. Importance of speech production for phonological awareness and word decoding: the case of children with cerebral palsy.

    NARCIS (Netherlands)

    Peeters, M.; Verhoeven, L.; Moor, J.M.H. de; Balkom, H. van

    2009-01-01

    The goal of this longitudinal study was to investigate the precursors of early reading development in 52 children with cerebral palsy at kindergarten level in comparison to 65 children without disabilities. Word Decoding was measured to investigate early reading skills, while Phonological Awareness,

  2. Decoding Signal Processing at the Single-Cell Level

    Energy Technology Data Exchange (ETDEWEB)

    Wiley, H. Steven

    2017-12-01

    The ability of cells to detect and decode information about their extracellular environment is critical to generating an appropriate response. In multicellular organisms, cells must decode dozens of signals from their neighbors and extracellular matrix to maintain tissue homeostasis while still responding to environmental stressors. How cells detect and process information from their surroundings through a surprisingly limited number of signal transduction pathways is one of the most important question in biology. Despite many decades of research, many of the fundamental principles that underlie cell signal processing remain obscure. However, in this issue of Cell Systems, Gillies et al present compelling evidence that the early response gene circuit can act as a linear signal integrator, thus providing significant insight into how cells handle fluctuating signals and noise in their environment.

  3. The emergence of automaticity in reading: Effects of orthographic depth and word decoding ability on an adjusted Stroop measure.

    Science.gov (United States)

    Megherbi, Hakima; Elbro, Carsten; Oakhill, Jane; Segui, Juan; New, Boris

    2018-02-01

    How long does it take for word reading to become automatic? Does the appearance and development of automaticity differ as a function of orthographic depth (e.g., French vs. English)? These questions were addressed in a longitudinal study of English and French beginning readers. The study focused on automaticity as obligatory processing as measured in the Stroop test. Measures of decoding ability and the Stroop effect were taken at three time points during first grade (and during second grade in the United Kingdom) in 84 children. The study is the first to adjust the classic Stroop effect for inhibition (of distracting colors). The adjusted Stroop effect was zero in the absence of reading ability, and it was found to develop in tandem with decoding ability. After a further control for decoding, no effects of age or orthography were found on the adjusted Stroop measure. The results are in line with theories of the development of whole word recognition that emphasize the importance of the acquisition of the basic orthographic code. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. The emergence of automaticity in reading: effects of orthographic depth and word decoding ability on an adjusted Stroop measure

    OpenAIRE

    Megherbi, Hakima; Elbro, Carsten; Oakhill, Jane; Segui, Juan; New, Boris

    2017-01-01

    Abstract\\ud Aims\\ud How long does it take for word reading to become automatic? Does the appearance and development of automaticity differ as a function of orthographic depth (e.g. French vs. English)? These questions were addressed in a longitudinal study of English and French beginning readers. The study focused on automaticity as obligatory processing as measured in the Stroop test. \\ud Method\\ud Measures of decoding ability and the Stroop effect were taken at three time points during the ...

  5. The role of short-term memory impairment in nonword repetition, real word repetition, and nonword decoding: A case study.

    Science.gov (United States)

    Peter, Beate

    2017-09-21

    In a companion study, adults with dyslexia and adults with a probable history of childhood apraxia of speech showed evidence of difficulty with processing sequential information during nonword repetition, multisyllabic real word repetition and nonword decoding. Results suggested that some errors arose in visual encoding during nonword reading, all levels of processing but especially short-term memory storage/retrieval during nonword repetition, and motor planning and programming during complex real word repetition. To further investigate the role of short-term memory, a participant with short-term memory impairment (MI) was recruited. MI was confirmed with poor performance during a sentence repetition and three nonword repetition tasks, all of which have a high short-term memory load, whereas typical performance was observed during tests of reading, spelling, and static verbal knowledge, all with low short-term memory loads. Experimental results show error-free performance during multisyllabic real word repetition but high counts of sequence errors, especially migrations and assimilations, during nonword repetition, supporting short-term memory as a locus of sequential processing deficit during nonword repetition. Results are also consistent with the hypothesis that during complex real word repetition, short-term memory is bypassed as the word is recognized and retrieved from long-term memory prior to producing the word.

  6. Single-Word Recognition Need Not Depend on Single-Word Features: Narrative Coherence Counteracts Effects of Single-Word Features That Lexical Decision Emphasizes

    Science.gov (United States)

    Teng, Dan W.; Wallot, Sebastian; Kelty-Stephen, Damian G.

    2016-01-01

    Research on reading comprehension of connected text emphasizes reliance on single-word features that organize a stable, mental lexicon of words and that speed or slow the recognition of each new word. However, the time needed to recognize a word might not actually be as fixed as previous research indicates, and the stability of the mental lexicon…

  7. Decoding speech perception by native and non-native speakers using single-trial electrophysiological data.

    Directory of Open Access Journals (Sweden)

    Alex Brandmeyer

    Full Text Available Brain-computer interfaces (BCIs are systems that use real-time analysis of neuroimaging data to determine the mental state of their user for purposes such as providing neurofeedback. Here, we investigate the feasibility of a BCI based on speech perception. Multivariate pattern classification methods were applied to single-trial EEG data collected during speech perception by native and non-native speakers. Two principal questions were asked: 1 Can differences in the perceived categories of pairs of phonemes be decoded at the single-trial level? 2 Can these same categorical differences be decoded across participants, within or between native-language groups? Results indicated that classification performance progressively increased with respect to the categorical status (within, boundary or across of the stimulus contrast, and was also influenced by the native language of individual participants. Classifier performance showed strong relationships with traditional event-related potential measures and behavioral responses. The results of the cross-participant analysis indicated an overall increase in average classifier performance when trained on data from all participants (native and non-native. A second cross-participant classifier trained only on data from native speakers led to an overall improvement in performance for native speakers, but a reduction in performance for non-native speakers. We also found that the native language of a given participant could be decoded on the basis of EEG data with accuracy above 80%. These results indicate that electrophysiological responses underlying speech perception can be decoded at the single-trial level, and that decoding performance systematically reflects graded changes in the responses related to the phonological status of the stimuli. This approach could be used in extensions of the BCI paradigm to support perceptual learning during second language acquisition.

  8. Exploring Differential Effects Across Two Decoding Treatments on Item-Level Transfer in Children with Significant Word Reading Difficulties: A New Approach for Testing Intervention Elements

    Science.gov (United States)

    Steacy, Laura M.; Elleman, Amy M.; Lovett, Maureen W.; Compton, Donald L.

    2016-01-01

    In English, gains in decoding skill do not map directly onto increases in word reading. However, beyond the Self-Teaching Hypothesis (Share, 1995), little is known about the transfer of decoding skills to word reading. In this study, we offer a new approach to testing specific decoding elements on transfer to word reading. To illustrate, we modeled word-reading gains among children with reading disability (RD) enrolled in Phonological and Strategy Training (PHAST) or Phonics for Reading (PFR). Conditions differed in sublexical training with PHAST stressing multi-level connections and PFR emphasizing simple grapheme-phoneme correspondences. Thirty-seven children with RD, 3rd – 6th grade, were randomly assigned 60 lessons of PHAST or PFR. Crossed random-effects models allowed us to identify specific intervention elements that differentially impacted word-reading performance at posttest, with children in PHAST better able to read words with variant vowel pronunciations. Results suggest that sublexical emphasis influences transfer gains to word reading. PMID:28596701

  9. Iterative List Decoding

    DEFF Research Database (Denmark)

    Justesen, Jørn; Høholdt, Tom; Hjaltason, Johan

    2005-01-01

    We analyze the relation between iterative decoding and the extended parity check matrix. By considering a modified version of bit flipping, which produces a list of decoded words, we derive several relations between decodable error patterns and the parameters of the code. By developing a tree...

  10. Morphology and Vocabulary Acquisition: Using Visual Cues from Word Parts to Enhance Recall and Decode Newly Encountered Words

    Science.gov (United States)

    Bellomo, Tom

    2012-01-01

    An enhanced replication of an original quasi-experiment (Tom Bellomo, 2009b) was conducted to quantify the extent of long term retention of word parts and vocabulary. Such were introduced as part of a vocabulary acquisition strategy in a developmental reading course at one southeast four-year college. Aside from incorporating changes to the test…

  11. The Role of Word Decoding, Vocabulary Knowledge and Meta-Cognitive Knowledge in Monolingual and Bilingual Low-Achieving Adolescents' Reading Comprehension

    Science.gov (United States)

    van Steensel, Roel; Oostdam, Ron; van Gelderen, Amos; van Schooten, Erik

    2016-01-01

    In this study, we analysed the relationships between word decoding, vocabulary knowledge, meta-cognitive knowledge and reading comprehension in low-achieving adolescents and examined whether the strength of these relationships differed between Grade 7 and 9 students and between monolingual and bilingual students. Tests were administered to 328…

  12. Decoding of articulatory gestures during word production using speech motor and premotor cortical activity.

    Science.gov (United States)

    Mugler, Emily M; Goldrick, Matthew; Rosenow, Joshua M; Tate, Matthew C; Slutzky, Marc W

    2015-01-01

    Brain-machine interfaces that directly translate attempted speech from the speech motor areas could change the lives of people with complete paralysis. However, it remains uncertain exactly how speech production is encoded in cortex. Improving this understanding could greatly improve brain-machine interface design. Specifically, it is not clear to what extent the different levels of speech production (phonemes, or speech sounds, and articulatory gestures, which describe the movements of the articulator muscles) are represented in the motor cortex. Using electrocorticographic (ECoG) electrodes on the cortical surface, we recorded neural activity from speech motor and premotor areas during speech production. We decoded both gestures and phonemes using the neural signals. Overall classification accuracy was higher for gestures than phonemes. In particular, gestures were better represented in the primary sensorimotor cortices, while phonemes were better represented in more anterior areas.

  13. Semantic effects in single-word naming.

    Science.gov (United States)

    Strain, E; Patterson, K; Seidenberg, M S

    1995-09-01

    Three experiments demonstrated that, for lower frequency words, reading aloud is affected not only by spelling-sound typicality but also by a semantic variable, imageability. Participants were slower and more error prone when naming exception words with abstract meanings (e.g., scarce) than when naming either abstract regular words (e.g., scribe) or imageable exception words (e.g., soot). It is proposed that semantic representations of words have the largest impact on translating orthography to phonology when this translation process is slow or noisy (i.e., for low-frequency exceptions) and that words with rich semantic representations (i.e., high-imageability words) are most likely to benefit from this interaction.

  14. Quantitative evaluation of muscle synergy models: a single-trial task decoding approach

    Directory of Open Access Journals (Sweden)

    Ioannis eDelis

    2013-02-01

    Full Text Available Muscle synergies, i.e. invariant coordinated activations of groups of muscles, have been proposed as building blocks that the central nervous system uses to construct the patterns of muscle activity utilized for executing movements. Several efficient dimensionality reduction algorithms that extract putative synergies from electromyographic (EMG signals have been developed. Typically, the quality of synergy decompositions is assessed by computing the variance accounted for (VAF. Yet, little is known about the extent to which the combination of those synergies encodes task-discriminating variations of muscle activity in individual trials. To address this question, here we conceive and develop a novel computational framework to evaluate muscle synergy decompositions in task space. Unlike previous methods considering the total variance of muscle patterns (VAF based metrics, our approach focuses on variance discriminating execution of different tasks. The procedure is based on single-trial task decoding from muscle synergy activation features. The task decoding based metric evaluates quantitatively the mapping between synergy recruitment and task identification and automatically determines the minimal number of synergies that captures all the task-discriminating variability in the synergy activations. In this paper, we first validate the method on plausibly simulated EMG datasets. We then show that it can be applied to different types of muscle synergy decomposition and illustrate its applicability to real data by using it for the analysis of EMG recordings during an arm pointing task. We find that time-varying and synchronous synergies with similar number of parameters are equally efficient in task decoding, suggesting that in this experimental paradigm they are equally valid representations of muscle synergies. Overall, these findings stress the effectiveness of the decoding metric in systematically assessing muscle synergy decompositions in task

  15. Quantitative evaluation of muscle synergy models: a single-trial task decoding approach.

    Science.gov (United States)

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

    2013-01-01

    Muscle synergies, i.e., invariant coordinated activations of groups of muscles, have been proposed as building blocks that the central nervous system (CNS) uses to construct the patterns of muscle activity utilized for executing movements. Several efficient dimensionality reduction algorithms that extract putative synergies from electromyographic (EMG) signals have been developed. Typically, the quality of synergy decompositions is assessed by computing the Variance Accounted For (VAF). Yet, little is known about the extent to which the combination of those synergies encodes task-discriminating variations of muscle activity in individual trials. To address this question, here we conceive and develop a novel computational framework to evaluate muscle synergy decompositions in task space. Unlike previous methods considering the total variance of muscle patterns (VAF based metrics), our approach focuses on variance discriminating execution of different tasks. The procedure is based on single-trial task decoding from muscle synergy activation features. The task decoding based metric evaluates quantitatively the mapping between synergy recruitment and task identification and automatically determines the minimal number of synergies that captures all the task-discriminating variability in the synergy activations. In this paper, we first validate the method on plausibly simulated EMG datasets. We then show that it can be applied to different types of muscle synergy decomposition and illustrate its applicability to real data by using it for the analysis of EMG recordings during an arm pointing task. We find that time-varying and synchronous synergies with similar number of parameters are equally efficient in task decoding, suggesting that in this experimental paradigm they are equally valid representations of muscle synergies. Overall, these findings stress the effectiveness of the decoding metric in systematically assessing muscle synergy decompositions in task space.

  16. Decoding sequence learning from single-trial intracranial EEG in humans.

    Directory of Open Access Journals (Sweden)

    Marzia De Lucia

    Full Text Available We propose and validate a multivariate classification algorithm for characterizing changes in human intracranial electroencephalographic data (iEEG after learning motor sequences. The algorithm is based on a Hidden Markov Model (HMM that captures spatio-temporal properties of the iEEG at the level of single trials. Continuous intracranial iEEG was acquired during two sessions (one before and one after a night of sleep in two patients with depth electrodes implanted in several brain areas. They performed a visuomotor sequence (serial reaction time task, SRTT using the fingers of their non-dominant hand. Our results show that the decoding algorithm correctly classified single iEEG trials from the trained sequence as belonging to either the initial training phase (day 1, before sleep or a later consolidated phase (day 2, after sleep, whereas it failed to do so for trials belonging to a control condition (pseudo-random sequence. Accurate single-trial classification was achieved by taking advantage of the distributed pattern of neural activity. However, across all the contacts the hippocampus contributed most significantly to the classification accuracy for both patients, and one fronto-striatal contact for one patient. Together, these human intracranial findings demonstrate that a multivariate decoding approach can detect learning-related changes at the level of single-trial iEEG. Because it allows an unbiased identification of brain sites contributing to a behavioral effect (or experimental condition at the level of single subject, this approach could be usefully applied to assess the neural correlates of other complex cognitive functions in patients implanted with multiple electrodes.

  17. Single-Trial Decoding of Bistable Perception Based on Sparse Nonnegative Tensor Decomposition

    Science.gov (United States)

    Wang, Zhisong; Maier, Alexander; Logothetis, Nikos K.; Liang, Hualou

    2008-01-01

    The study of the neuronal correlates of the spontaneous alternation in perception elicited by bistable visual stimuli is promising for understanding the mechanism of neural information processing and the neural basis of visual perception and perceptual decision-making. In this paper, we develop a sparse nonnegative tensor factorization-(NTF)-based method to extract features from the local field potential (LFP), collected from the middle temporal (MT) visual cortex in a macaque monkey, for decoding its bistable structure-from-motion (SFM) perception. We apply the feature extraction approach to the multichannel time-frequency representation of the intracortical LFP data. The advantages of the sparse NTF-based feature extraction approach lies in its capability to yield components common across the space, time, and frequency domains yet discriminative across different conditions without prior knowledge of the discriminating frequency bands and temporal windows for a specific subject. We employ the support vector machines (SVMs) classifier based on the features of the NTF components for single-trial decoding the reported perception. Our results suggest that although other bands also have certain discriminability, the gamma band feature carries the most discriminative information for bistable perception, and that imposing the sparseness constraints on the nonnegative tensor factorization improves extraction of this feature. PMID:18528515

  18. Decoded fMRI neurofeedback can induce bidirectional confidence changes within single participants.

    Science.gov (United States)

    Cortese, Aurelio; Amano, Kaoru; Koizumi, Ai; Lau, Hakwan; Kawato, Mitsuo

    2017-04-01

    Neurofeedback studies using real-time functional magnetic resonance imaging (rt-fMRI) have recently incorporated the multi-voxel pattern decoding approach, allowing for fMRI to serve as a tool to manipulate fine-grained neural activity embedded in voxel patterns. Because of its tremendous potential for clinical applications, certain questions regarding decoded neurofeedback (DecNef) must be addressed. Specifically, can the same participants learn to induce neural patterns in opposite directions in different sessions? If so, how does previous learning affect subsequent induction effectiveness? These questions are critical because neurofeedback effects can last for months, but the short- to mid-term dynamics of such effects are unknown. Here we employed a within-subjects design, where participants underwent two DecNef training sessions to induce behavioural changes of opposing directionality (up or down regulation of perceptual confidence in a visual discrimination task), with the order of training counterbalanced across participants. Behavioral results indicated that the manipulation was strongly influenced by the order and the directionality of neurofeedback training. We applied nonlinear mathematical modeling to parametrize four main consequences of DecNef: main effect of change in confidence, strength of down-regulation of confidence relative to up-regulation, maintenance of learning effects, and anterograde learning interference. Modeling results revealed that DecNef successfully induced bidirectional confidence changes in different sessions within single participants. Furthermore, the effect of up- compared to down-regulation was more prominent, and confidence changes (regardless of the direction) were largely preserved even after a week-long interval. Lastly, the effect of the second session was markedly diminished as compared to the effect of the first session, indicating strong anterograde learning interference. These results are interpreted in the framework

  19. Decoded fMRI neurofeedback can induce bidirectional confidence changes within single participants

    Science.gov (United States)

    Cortese, Aurelio; Amano, Kaoru; Koizumi, Ai; Lau, Hakwan; Kawato, Mitsuo

    2017-01-01

    Neurofeedback studies using real-time functional magnetic resonance imaging (rt-fMRI) have recently incorporated the multi-voxel pattern decoding approach, allowing for fMRI to serve as a tool to manipulate fine-grained neural activity embedded in voxel patterns. Because of its tremendous potential for clinical applications, certain questions regarding decoded neurofeedback (DecNef) must be addressed. Specifically, can the same participants learn to induce neural patterns in opposite directions in different sessions? If so, how does previous learning affect subsequent induction effectiveness? These questions are critical because neurofeedback effects can last for months, but the short- to mid-term dynamics of such effects are unknown. Here we employed a within-subjects design, where participants underwent two DecNef training sessions to induce behavioural changes of opposing directionality (up or down regulation of perceptual confidence in a visual discrimination task), with the order of training counterbalanced across participants. Behavioral results indicated that the manipulation was strongly influenced by the order and the directionality of neurofeedback training. We applied nonlinear mathematical modeling to parametrize four main consequences of DecNef: main effect of change in confidence, strength of down-regulation of confidence relative to up-regulation, maintenance of learning effects, and anterograde learning interference. Modeling results revealed that DecNef successfully induced bidirectional confidence changes in different sessions within single participants. Furthermore, the effect of up- compared to down-regulation was more prominent, and confidence changes (regardless of the direction) were largely preserved even after a week-long interval. Lastly, the effect of the second session was markedly diminished as compared to the effect of the first session, indicating strong anterograde learning interference. These results are interpreted in the framework

  20. Reading comprehension, word decoding and spelling in girls with autism spectrum disorders (ASD) or attention-deficit/hyperactivity disorder (AD/HD): performance and predictors.

    Science.gov (United States)

    Asberg, Jakob; Kopp, Svenny; Berg-Kelly, Kristina; Gillberg, Christopher

    2010-01-01

    Difficulties with aspects of literacy are often seen in children with autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (AD/HD). The bases of the connections between these disorders and literacy difficulties are poorly understood. Furthermore, it is not clear if existing research is representative for girls. There were three aims: (1) to compare performance in reading comprehension, word decoding, and spelling in girls with ASD (n = 20), AD/ HD (n = 36), and community girls with typical developing (girls; n = 54); (2) to assess rates of reading and writing disorders within groups; and (3) to examine the predictive value of measures of autistic and AD/HD symptomatology to reading comprehension in the whole girl sample. Participants were aged between 8 and 17 years, and had a full scale IQ>70. Standardized tests of literacy, oral vocabulary, and non-verbal ability were administered. Parent ratings of degree of autistic symptomatology and both parent and teacher ratings of AD/HD symptomatology were collected for all girls. Girls with diagnosed ASD could not be separated significantly from typically developing girls or girls with AD/HD on average performance on any literacy test. However, among girls with ASD, 40% had at least one reading and writing disorder. Girls with AD/HD performed lower than typically developing girls in reading comprehension, word decoding, and spelling, and 56% had at least one reading and writing disorder. In regression analysis, using the total sample, both degrees of autistic and AD/HD symptomatology negatively contributed to the variance in reading comprehension after controlling for oral vocabulary, word decoding, and non-verbal ability. Whereas AD/HD contributed to the variance in reading comprehension once autistic symptomatology was controlled for, the opposite was not true. However, a large bivariate correlation between autistic and AD/HD symptomatology somewhat complicates the interpretation of that result

  1. Decoding of single-trial auditory mismatch responses for online perceptual monitoring and neurofeedback

    Directory of Open Access Journals (Sweden)

    Alex eBrandmeyer

    2013-12-01

    Full Text Available Multivariate pattern classification methods are increasingly applied to neuroimaging data in the context of both fundamental research and in brain-computer interfacing approaches. Such methods provide a framework for interpreting measurements made at the single-trial level with respect to a set of two or more distinct mental states. Here, we define an approach in which the output of a binary classifier trained on data from an auditory mismatch paradigm can be used for online tracking of perception and as a neurofeedback signal. The auditory mismatch paradigm is known to induce distinct perceptual states related to the presentation of high- and low-probability stimuli, which are reflected in event-related potential (ERP components such as the mismatch negativity (MMN. In the first part of the paper, we illustrate how pattern classification methods can be applied to data collected in an MMN paradigm, including discussion of the optimization of preprocessing steps, the interpretation of features and how the performance of these methods generalizes across individual participants and measurement sessions. We then go on to show that the output of these decoding methods can be used in online settings as a continuous index of single-trial brain activation underlying perceptual discrimination. We conclude by discussing several potential domains of application, including neurofeedback, cognitive monitoring and passive brain-computer interfaces.

  2. Thinking Aloud about L2 Decoding: An Exploration of the Strategies Used by Beginner Learners when Pronouncing Unfamiliar French Words

    Science.gov (United States)

    Woore, Robert

    2010-01-01

    "Decoding"--converting the written symbols (or graphemes) of an alphabetical writing system into the sounds (or phonemes) they represent, using knowledge of the language's symbol/sound correspondences--has been argued to be an important but neglected skill in the teaching of second language (L2) French in English secondary schools.…

  3. The syntax of single words: Evidence from a patient with a selective function word reading deficit.

    Science.gov (United States)

    Druks, Judit; Froud, Karen

    2002-05-01

    We describe the reading performance of a patient who has selective deficits for reading nonwords, function words, and morphologically complex words in isolation. His reading of highly abstract nouns and verbs, however, is relatively well preserved. He can recognise and comprehend the meaning of written function words, of derivational morphology, and of most inflectional morphology. We suggest that his deficit in reading grammatical morphemes is unrelated to his problems in reading nonwords and cannot be explained by their low semanticity and imageability. The patient's speech is ungrammatical but is not devoid of grammatical morphemes and his reading of functional elements improves when these are presented within the context of sentences. We argue that syntactic information relevant to individual lexical items including information about how the word may potentially be used within a phrase must be accessed during single word reading tasks (e.g., Levelt, 1989). This is particularly difficult for function words due to their linguistic specification, which is different from that of lexical categories (Chomsky, 1995). Both linguistic theory and Garrett's (e.g., 1982) model of sentence processing account for the patient's improved reading of function words in the context of sentences.

  4. The effects of video self-modeling on the decoding skills of children at risk for reading disabilities

    OpenAIRE

    Ayala, SM; O'Connor, R

    2013-01-01

    Ten first grade students who had responded poorly to a Tier 2 reading intervention in a response to intervention (RTI) model received an intervention of video self-modeling to improve decoding skills and sight word recognition. Students were video recorded blending and segmenting decodable words and reading sight words. Videos were edited and viewed a minimum of four times per week. Data were collected twice per week using curriculum-based measures. A single subject multiple baseline across p...

  5. Decoded fMRI neurofeedback can induce bidirectional confidence changes within single participants

    OpenAIRE

    Cortese, Aurelio; Amano, Kaoru; Koizumi, Ai; Lau, Hakwan; Kawato, Mitsuo

    2017-01-01

    Neurofeedback studies using real-time functional magnetic resonance imaging (rt-fMRI) have recently incorporated the multi-voxel pattern decoding approach, allowing for fMRI to serve as a tool to manipulate fine-grained neural activity embedded in voxel patterns. Because of its tremendous potential for clinical applications, certain questions regarding decoded neurofeedback (DecNef) must be addressed. Specifically, can the same participants learn to induce neural patterns in opposite directio...

  6. Brain-based translation: fMRI decoding of spoken words in bilinguals reveals language-independent semantic representations in anterior temporal lobe.

    Science.gov (United States)

    Correia, João; Formisano, Elia; Valente, Giancarlo; Hausfeld, Lars; Jansma, Bernadette; Bonte, Milene

    2014-01-01

    Bilinguals derive the same semantic concepts from equivalent, but acoustically different, words in their first and second languages. The neural mechanisms underlying the representation of language-independent concepts in the brain remain unclear. Here, we measured fMRI in human bilingual listeners and reveal that response patterns to individual spoken nouns in one language (e.g., "horse" in English) accurately predict the response patterns to equivalent nouns in the other language (e.g., "paard" in Dutch). Stimuli were four monosyllabic words in both languages, all from the category of "animal" nouns. For each word, pronunciations from three different speakers were included, allowing the investigation of speaker-independent representations of individual words. We used multivariate classifiers and a searchlight method to map the informative fMRI response patterns that enable decoding spoken words within languages (within-language discrimination) and across languages (across-language generalization). Response patterns discriminative of spoken words within language were distributed in multiple cortical regions, reflecting the complexity of the neural networks recruited during speech and language processing. Response patterns discriminative of spoken words across language were limited to localized clusters in the left anterior temporal lobe, the left angular gyrus and the posterior bank of the left postcentral gyrus, the right posterior superior temporal sulcus/superior temporal gyrus, the right medial anterior temporal lobe, the right anterior insula, and bilateral occipital cortex. These results corroborate the existence of "hub" regions organizing semantic-conceptual knowledge in abstract form at the fine-grained level of within semantic category discriminations.

  7. Decoding Dyslexia, a Common Learning Disability

    Science.gov (United States)

    ... of this page please turn JavaScript on. Feature: Dyslexia Decoding Dyslexia, a Common Learning Disability Past Issues / Winter 2016 ... Dyslexic" Articles In Their Own Words: Dealing with Dyslexia / Decoding Dyslexia, a Common Learning Disability / What is ...

  8. The relation between executive functioning, reaction time, naming speed, and single word reading in children with typical development and language impairments.

    Science.gov (United States)

    Messer, David; Henry, Lucy A; Nash, Gilly

    2016-09-01

    Few investigations have examined the relationship between a comprehensive range of executive functioning (EF) abilities and reading. Our investigation identified components of EF that independently predicted single word reading, and determined whether their predictive role remained when additional variables were included in the regression analyses. This provided information about the EF processes that are related to reading, and the unity and diversity of EF. This study consisted of 160 children: 88 were typically developing with no language difficulties; 72 had language impairments. The assessments involved decoding, 10 measures of EF, reaction time, naming speed, non-verbal and verbal age-equivalent scores. In the first regression analysis, which only concerned the EF variables, the following verbal forms of EF had significant relationships with decoding: working memory, fluency, planning, and inhibition. Further regression analyses included additional predictor variables: reaction time, naming speed, and age-equivalent scores. These analyses indicated that most of the EF variables continued to predict decoding even when entered with competitor variables. Furthermore, after the entry of EF variables, there were no group differences in decoding (typical vs. language difficulties). We discuss the contribution of EF and other variables to reading abilities. © 2016 The British Psychological Society.

  9. The Scope of Facilitation of Word Recognition from Single Word and Sentence Frame Contexts. Technical Report No. 133.

    Science.gov (United States)

    Kleiman, Glenn M.

    Two experiments explored whether the facilitatory effect of context on lexical decisions is limited to words subjects generated when given the context as a prompt in a production task, or if the effect is wider in scope. The first experiment provided evidence of a wide scope of facilitation from single word contexts. In the second experiment, the…

  10. JSATS Decoder Software Manual

    Energy Technology Data Exchange (ETDEWEB)

    Flory, Adam E.; Lamarche, Brian L.; Weiland, Mark A.

    2013-05-01

    The Juvenile Salmon Acoustic Telemetry System (JSATS) Decoder is a software application that converts a digitized acoustic signal (a waveform stored in the .bwm file format) into a list of potential JSATS Acoustic MicroTransmitter (AMT) tagcodes along with other data about the signal including time of arrival and signal to noise ratios (SNR). This software is capable of decoding single files, directories, and viewing raw acoustic waveforms. When coupled with the JSATS Detector, the Decoder is capable of decoding in ‘real-time’ and can also provide statistical information about acoustic beacons placed within receive range of hydrophones within a JSATS array. This document details the features and functionality of the software. The document begins with software installation instructions (section 2), followed in order by instructions for decoder setup (section 3), decoding process initiation (section 4), then monitoring of beacons (section 5) using real-time decoding features. The last section in the manual describes the beacon, beacon statistics, and the results file formats. This document does not consider the raw binary waveform file format.

  11. Multivariate Bayesian decoding of single-trial event-related fMRI responses for memory retrieval of voluntary actions.

    Directory of Open Access Journals (Sweden)

    Dongha Lee

    Full Text Available This study proposes a method for classifying event-related fMRI responses in a specialized setting of many known but few unknown stimuli presented in a rapid event-related design. Compared to block design fMRI signals, classification of the response to a single or a few stimulus trial(s is not a trivial problem due to contamination by preceding events as well as the low signal-to-noise ratio. To overcome such problems, we proposed a single trial-based classification method of rapid event-related fMRI signals utilizing sparse multivariate Bayesian decoding of spatio-temporal fMRI responses. We applied the proposed method to classification of memory retrieval processes for two different classes of episodic memories: a voluntarily conducted experience and a passive experience induced by watching a video of others' actions. A cross-validation showed higher classification performance of the proposed method compared to that of a support vector machine or of a classifier based on the general linear model. Evaluation of classification performances for one, two, and three stimuli from the same class and a correlation analysis between classification accuracy and target stimulus positions among trials suggest that presenting two target stimuli at longer inter-stimulus intervals is optimal in the design of classification experiments to identify the target stimuli. The proposed method for decoding subject-specific memory retrieval of voluntary behavior using fMRI would be useful in forensic applications in a natural environment, where many known trials can be extracted from a simulation of everyday tasks and few target stimuli from a crime scene.

  12. Measuring word complexity in speech screening: single-word sampling to identify phonological delay/disorder in preschool children.

    Science.gov (United States)

    Anderson, Carolyn; Cohen, Wendy

    2012-01-01

    Children's speech sound development is assessed by comparing speech production with the typical development of speech sounds based on a child's age and developmental profile. One widely used method of sampling is to elicit a single-word sample along with connected speech. Words produced spontaneously rather than imitated may give a more accurate indication of a child's speech development. A published word complexity measure can be used to score later-developing speech sounds and more complex word patterns. There is a need for a screening word list that is quick to administer and reliably differentiates children with typically developing speech from children with patterns of delayed/disordered speech. To identify a short word list based on word complexity that could be spontaneously named by most typically developing children aged 3;00-5;05 years. One hundred and five children aged between 3;00 and 5;05 years from three local authority nursery schools took part in the study. Items from a published speech assessment were modified and extended to include a range of phonemic targets in different word positions in 78 monosyllabic and polysyllabic words. The 78 words were ranked both by phonemic/phonetic complexity as measured by word complexity and by ease of spontaneous production. The ten most complex words (hereafter Triage 10) were named spontaneously by more than 90% of the children. There was no significant difference between the complexity measures for five identified age groups when the data were examined in 6-month groups. A qualitative analysis revealed eight children with profiles of phonological delay or disorder. When these children were considered separately, there was a statistically significant difference (p speech from those with delayed or disordered speech patterns. The Triage 10 words can be used as a screening tool for triage and general assessment and have the potential to monitor progress during intervention. Further testing is being undertaken to

  13. Learning transitive verbs from single-word verbs in the input by young children acquiring English.

    Science.gov (United States)

    Ninio, Anat

    2016-09-01

    The environmental context of verbs addressed by adults to young children is claimed to be uninformative regarding the verbs' meaning, yielding the Syntactic Bootstrapping Hypothesis that, for verb learning, full sentences are needed to demonstrate the semantic arguments of verbs. However, reanalysis of Gleitman's (1990) original data regarding input to a blind child revealed the context of single-word parental verbs to be more transparent than that of sentences. We tested the hypothesis that English-speaking children learn their early verbs from parents' single-word utterances. Distribution of single-word transitive verbs produced by a large sample of young children was strongly predicted by the relative token frequency of verbs in parental single-word utterances, but multiword sentences had no predictive value. Analysis of the interactive context showed that objects of verbs are retrievable by pragmatic inference, as is the meaning of the verbs. Single-word input appears optimal for learning an initial vocabulary of verbs.

  14. Single Word and Sentence Intelligibility in Children with Cochlear Implants

    Science.gov (United States)

    Khwaileh, Fadwa A.; Flipsen, Peter, Jr.

    2010-01-01

    This study examined the intelligibility of speech produced by 17 children (aged 4-11 years) with cochlear implants. Stimulus items included sentences from the Beginners' Intelligibility Test (BIT) and words from the Children Speech Intelligibility Measure (CSIM). Naive listeners responded by writing sentences heard or with two types of responses…

  15. Production Variability and Single Word Intelligibility in Aphasia and Apraxia of Speech

    Science.gov (United States)

    Haley, Katarina L.; Martin, Gwenyth

    2011-01-01

    This study was designed to estimate test-retest reliability of orthographic speech intelligibility testing in speakers with aphasia and AOS and to examine its relationship to the consistency of speaker and listener responses. Monosyllabic single word speech samples were recorded from 13 speakers with coexisting aphasia and AOS. These words were…

  16. Foveational Complexity in Single Word Identification: Contralateral Visual Pathways Are Advantaged over Ipsilateral Pathways

    Science.gov (United States)

    Obregon, Mateo; Shillcock, Richard

    2012-01-01

    Recognition of a single word is an elemental task in innumerable cognitive psychology experiments, but involves unexpected complexity. We test a controversial claim that the human fovea is vertically divided, with each half projecting to either the contralateral or ipsilateral hemisphere, thereby influencing foveal word recognition. We report a…

  17. Advance Planning of Form Properties in the Written Production of Single and Multiple Words

    Science.gov (United States)

    Damian, Markus F.; Stadthagen-Gonzalez, Hans

    2009-01-01

    Three experiments investigated the scope of advance planning in written production. Experiment 1 manipulated phonological factors in single word written production, and Experiments 2 and 3 did the same in the production of adjective-noun utterances. In all three experiments, effects on latencies were found which mirrored those previously…

  18. The effect of a carrier phrase on hearing aid amplification of single words in quiet

    NARCIS (Netherlands)

    Versfeld, N.J.; Goverts, S.T.

    2013-01-01

    Objective: A common method to assess the functional benefit of hearing aids is by measuring the performance-intensity curve of single words in quiet with and without hearing aids. Currently, virtually all hearing aids use signal processing, which may have a marked effect on gain as a function of

  19. Content Coverage of Single-Word Tests Used to Assess Common Phonological Error Patterns

    Science.gov (United States)

    Kirk, Cecilia; Vigeland, Laura

    2015-01-01

    Purpose: This review evaluated whether 9 single-word tests of phonological error patterns provide adequate content coverage to accurately identify error patterns that are active in a child's speech. Method: Tests in the current study were considered to display sufficient opportunities to assess common phonological error patterns if they…

  20. The Effects of Video Self-Modeling on the Decoding Skills of Children At Risk for Reading Disabilities

    OpenAIRE

    Ayala, Sandra M

    2010-01-01

    Ten first grade students, participating in a Tier II response to intervention (RTI) reading program received an intervention of video self modeling to improve decoding skills and sight word recognition. The students were video recorded blending and segmenting decodable words, and reading sight words taken directly from their curriculum instruction. Individual videos were recorded and edited to show students successfully and accurately decoding words and practicing sight word recognition. Each...

  1. Individual Differences in Working Memory Capacity Modulates Semantic Negative Priming from Single Prime Words.

    Science.gov (United States)

    Ortells, Juan J; Noguera, Carmen; Álvarez, Dolores; Carmona, Encarna; Houghton, George

    2016-01-01

    The present study investigated whether semantic negative priming from single prime words depends on the availability of cognitive control resources. Participants with high vs. low working memory capacity (as assessed by their performance in complex span and attentional control tasks) were instructed to either attend to or ignore a briefly presented single prime word that was followed by either a semantically related or unrelated target word on which participants made a lexical decision. Individual differences in working memory capacity (WMC) mainly affected the processing of the ignored primes, but not the processing of the attended primes: While the latter produced reliable positive semantic priming for both high- and low-WMC participants, the former gave rise to reliable semantic negative priming only for high WMC participants, with low WMC participants showing the opposite positive priming effect. The present results extend previous findings in demonstrating that (a) single negative priming can reliably generalize to semantic associates of the prime words, and (b) a differential availability of cognitive control resources can reliably modulate the negative priming effect at a semantic level of representation.

  2. Single-word multiple-bit upsets in static random access devices

    International Nuclear Information System (INIS)

    Koga, R.; Pinkerton, S.D.; Lie, T.J.; Crawford, K.B.

    1993-01-01

    Energetic ions and protons can cause single event upsets (SEUs) in static random access memory (SRAM) cells. In some cases multiple bits may be upset as the result of a single event. Space-borne electronics systems incorporating high-density SRAM are vulnerable to single-word multiple-bit upsets (SMUs). The authors review here recent observations of SMU, present the results of a systematic investigation of the physical cell arrangements employed in several currently available SRAM device types, and discuss implications for the occurrence and mitigation of SMU

  3. The Influence of Visual Word Form in Reading: Single Case Study of an Arabic Patient with Deep Dyslexia

    Science.gov (United States)

    Boumaraf, Assia; Macoir, Joël

    2016-01-01

    Deep dyslexia is a written language disorder characterized by poor reading of non-words, and advantage for concrete over abstract words with production of semantic, visual and morphological errors. In this single case study of an Arabic patient with input deep dyslexia, we investigated the impact of graphic features of Arabic on manifestations of…

  4. An electrophysiological investigation of the role of orthography in accessing meaning of Chinese single-character words.

    Science.gov (United States)

    Wang, Kui

    2011-01-10

    This study reported the role of orthography in semantic activation processes of Chinese single-character words. Eighteen native Chinese speaking adults were recruited to take part in a Stroop experiment consisting of one-character color words and pseudowords which were orthographically similar to these color words. Classic behavioral Stroop effects, namely longer reaction times for incongruent conditions than for congruent conditions, were demonstrated for color words and pseudowords. A clear N450 was also observed in the two incongruent conditions. The participants were also asked to perform a visual judgment task immediately following the Stroop experiment. Results from the visual judgment task showed that participants could distinguish color words and pseudowords well (with a mean accuracy rate over 90 percent). Taken together, these findings support the direct orthography-semantic route in Chinese one-character words. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  5. Decoding intention at sensorimotor timescales.

    Directory of Open Access Journals (Sweden)

    Mathew Salvaris

    Full Text Available The ability to decode an individual's intentions in real time has long been a 'holy grail' of research on human volition. For example, a reliable method could be used to improve scientific study of voluntary action by allowing external probe stimuli to be delivered at different moments during development of intention and action. Several Brain Computer Interface applications have used motor imagery of repetitive actions to achieve this goal. These systems are relatively successful, but only if the intention is sustained over a period of several seconds; much longer than the timescales identified in psychophysiological studies for normal preparation for voluntary action. We have used a combination of sensorimotor rhythms and motor imagery training to decode intentions in a single-trial cued-response paradigm similar to those used in human and non-human primate motor control research. Decoding accuracy of over 0.83 was achieved with twelve participants. With this approach, we could decode intentions to move the left or right hand at sub-second timescales, both for instructed choices instructed by an external stimulus and for free choices generated intentionally by the participant. The implications for volition are considered.

  6. Selectivity of N170 for visual words in the right hemisphere: Evidence from single-trial analysis.

    Science.gov (United States)

    Yang, Hang; Zhao, Jing; Gaspar, Carl M; Chen, Wei; Tan, Yufei; Weng, Xuchu

    2017-08-01

    Neuroimaging and neuropsychological studies have identified the involvement of the right posterior region in the processing of visual words. Interestingly, in contrast, ERP studies of the N170 typically demonstrate selectivity for words more strikingly over the left hemisphere. Why is right hemisphere selectivity for words during the N170 epoch typically not observed, despite the clear involvement of this region in word processing? One possibility is that amplitude differences measured on averaged ERPs in previous studies may have been obscured by variation in peak latency across trials. This study examined this possibility by using single-trial analysis. Results show that words evoked greater single-trial N170s than control stimuli in the right hemisphere. Additionally, we observed larger trial-to-trial variability on N170 peak latency for words as compared to control stimuli over the right hemisphere. Results demonstrate that, in contrast to much of the prior literature, the N170 can be selective to words over the right hemisphere. This discrepancy is explained in terms of variability in trial-to-trial peak latency for responses to words over the right hemisphere. © 2017 Society for Psychophysiological Research.

  7. Multiscale brain-machine interface decoders.

    Science.gov (United States)

    Han-Lin Hsieh; Shanechi, Maryam M

    2016-08-01

    Brain-machine interfaces (BMI) have vastly used a single scale of neural activity, e.g., spikes or electrocorticography (ECoG), as their control signal. New technology allows for simultaneous recording of multiple scales of neural activity, from spikes to local field potentials (LFP) and ECoG. These advances introduce the new challenge of modeling and decoding multiple scales of neural activity jointly. Such multi-scale decoding is challenging for two reasons. First, spikes are discrete-valued and ECoG/LFP are continuous-valued, resulting in fundamental differences in statistical characteristics. Second, the time-scales of these signals are different, with spikes having a millisecond time-scale and ECoG/LFP having much slower time-scales on the order of tens of milliseconds. Here we develop a new multiscale modeling and decoding framework that addresses these challenges. Our multiscale decoder extracts information from ECoG/LFP in addition to spikes, while operating at the fast time-scale of the spikes. The multiscale decoder specializes to a Kalman filter (KF) or to a point process filter (PPF) when no spikes or ECoG/LFP are available, respectively. Using closed-loop BMI simulations, we show that compared to PPF decoding of spikes alone or KF decoding of LFP/ECoG alone, the multiscale decoder significantly improves the accuracy and error performance of BMI control and runs at the fast millisecond time-scale of the spikes. This new multiscale modeling and decoding framework has the potential to improve BMI control using simultaneous multiscale neural activity.

  8. High Speed Viterbi Decoder Architecture

    DEFF Research Database (Denmark)

    Paaske, Erik; Andersen, Jakob Dahl

    1998-01-01

    The fastest commercially available Viterbi decoders for the (171,133) standard rate 1/2 code operate with a decoding speed of 40-50 Mbit/s (net data rate). In this paper we present a suitable architecture for decoders operating with decoding speeds of 150-300 Mbit/s.......The fastest commercially available Viterbi decoders for the (171,133) standard rate 1/2 code operate with a decoding speed of 40-50 Mbit/s (net data rate). In this paper we present a suitable architecture for decoders operating with decoding speeds of 150-300 Mbit/s....

  9. Single Trial Decoding of Belief Decision Making from EEG and fMRI Data Using ICA Features

    Directory of Open Access Journals (Sweden)

    Pamela eDouglas

    2013-07-01

    Full Text Available The complex task of assessing the veracity of a statement is thought to activate uniquely distributed brain regions based on whether a subject believes or disbelieves a given assertion. In the current work, we present parallel machine learning methods for predicting a subject’s decision response to a given propositional statement based on independent component (IC features derived from EEG and fMRI data. Our results demonstrate that IC features outperformed features derived from event related spectral perturbations derived from any single spectral band, yet were similar to accuracy across all spectral bands combined. We compared our diagnostic IC spatial maps with our conventional general linear model (GLM results, and found that informative ICs had significant spatial overlap with our GLM results, yet also revealed unique regions like amygdala that were not statistically significant in GLM analyses. Overall, these results suggest that ICs may yield a parsimonious feature set that can be used along with a decision tree structure for interpretation of features used in classifying complex cognitive processes such as belief and disbelief across both fMRI and EEG neuroimaging modalities.

  10. Decoding Codes on Graphs

    Indian Academy of Sciences (India)

    lowing function is maximized,. This kind of decoding strategy is called the maximum a posteriori probability (MAP) decoding strategy as it attempts to estimate each symbol of the codeword that ..... gate the effects of packet loss over digital networks. Un- doubtedly other applications will use these codes in the years to come.

  11. Thin slices of creativity: using single-word utterances to assess creative cognition.

    Science.gov (United States)

    Prabhakaran, Ranjani; Green, Adam E; Gray, Jeremy R

    2014-09-01

    We investigated the hypothesis that individual differences in creative cognition can be manifest even in brief responses, such as single-word utterances. Participants (n = 193) were instructed to say a verb upon seeing a noun displayed on a computer screen and were cued to respond creatively to half of the nouns. For every noun-verb pair (72 pairs per subject), we assessed the semantic distance between the noun and the verb, using latent semantic analysis (LSA). Semantic distance was higher in the cued ("creative") condition than the uncued condition, within subjects. Critically, between subjects, semantic distance in the cued condition had a strong relationship to a creativity factor derived from a battery of verbal, nonverbal, and achievement-based creativity measures (β= .50), and this relation remained when controlling for intelligence and personality. The data show that creative cognition can be assessed reliably and validly from such thin slices of behavior.

  12. Grammatical gender in the production of single words: some evidence from Greek.

    Science.gov (United States)

    Plemmenou, Evangelia; Bard, Ellen G; Branigan, Holly P

    2002-01-01

    The present study investigated the effect of prior grammatical gender information provided by the production of a bare noun on the production of a syntactically unrelated, gender-inflected color adjective. The target language was Greek. A lexical priming task involving picture naming was employed. Participants saw a series of pictures, some in color and some in black-and-white; they had to name a black-and-white picture with the single noun (prime) and a color picture with the appropriately inflected color adjective (target). Prior gender information was shown to affect subsequent production of gender-marked words. The effect was restricted to nouns of one gender class (masculine) only. The implications of these results for the representation and processing of gender in production are discussed. Copyright 2001 Elsevier Science (USA).

  13. Studies of the Processing of Single Words Using Positron Tomographic Measures of Cerebral Blood Flow Change.

    Science.gov (United States)

    1987-01-01

    in dyslexia provide support for a direct route from visual word forms to semantic and articulatory codes. There also seems to be independence in the...experiment. (LaBerge & Samuels, 1974; Rumelhart & McClelland, 1982, 1986). ’-.Exam-es of some of these separate codes include a visual image of the...form of a spoken word ( visual code), pronunciation of the word (phonological code) or the association of related words (semantic codes). Studies of the

  14. Contextual constraints on lexico-semantic processing in aging: Evidence from single-word event-related brain potentials.

    Science.gov (United States)

    Payne, Brennan R; Federmeier, Kara D

    2018-05-15

    The current study reports the effects of accumulating contextual constraints on neural indices of lexico-semantic processing (i.e., effects of word frequency and orthographic neighborhood) as a function of normal aging. Event-related brain potentials were measured from a sample of older adults as they read sentences that were semantically congruent, provided only syntactic constraints (syntactic prose), or were random word strings. A linear mixed-effects modeling approach was used to probe the effects of accumulating contextual constraints on N400 responses to individual words. Like young adults in prior work, older adults exhibited a classic word position context effect on the N400 in congruent sentences, although the magnitude of the effect was reduced in older relative to younger adults. Moreover, by modeling single-word variability in N400 responses, we observed robust effects of orthographic neighborhood density that were larger in older adults than the young, and preserved effects word frequency. Importantly, in older adults, frequency effects were not modulated by accumulating contextual constraints, unlike in the young. Collectively, these findings indicate that older adults are less likely (or able) to use accumulating top-down contextual constraints, and therefore rely more strongly on bottom-up lexical features to guide semantic access of individual words during sentence comprehension. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Learning to Read Words: Theory, Findings, and Issues

    Science.gov (United States)

    Ehri, Linnea C.

    2005-01-01

    Reading words may take several forms. Readers may utilize decoding, analogizing, or predicting to read unfamiliar words. Readers read familiar words by accessing them in memory, called sight word reading. With practice, all words come to be read automatically by sight, which is the most efficient, unobtrusive way to read words in text. The process…

  16. Optimization of MPEG decoding

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren

    1999-01-01

    MPEG-2 video decoding is examined. A unified approach to quality improvement, chrominance upsampling, de-interlacing and superresolution is presented. The information over several frames is combined as part of the processing....

  17. The Neural Decoding Toolbox

    Directory of Open Access Journals (Sweden)

    Ethan eMeyers

    2013-05-01

    Full Text Available Population decoding is a powerful way to analyze neural data, however currently only a small percentage of systems neuroscience researchers use this method. In order to increase the use of population decoding, we have created the Neural Decoding Toolbox (NDT which is a Matlab package that makes it easy to apply population decoding analyses to neural activity. The design of the toolbox revolves around four abstract object classes which enables users to interchange particular modules in order to try different analyses while keeping the rest of the processing stream intact. The toolbox is capable of analyzing data from many different types of recording modalities, and we give examples of how it can be used to decode basic visual information from neural spiking activity and how it can be used to examine how invariant the activity of a neural population is to stimulus transformations. Overall this toolbox will make it much easier for neuroscientists to apply population decoding analyses to their data, which should help increase the pace of discovery in neuroscience.

  18. The neural decoding toolbox.

    Science.gov (United States)

    Meyers, Ethan M

    2013-01-01

    Population decoding is a powerful way to analyze neural data, however, currently only a small percentage of systems neuroscience researchers use this method. In order to increase the use of population decoding, we have created the Neural Decoding Toolbox (NDT) which is a Matlab package that makes it easy to apply population decoding analyses to neural activity. The design of the toolbox revolves around four abstract object classes which enables users to interchange particular modules in order to try different analyses while keeping the rest of the processing stream intact. The toolbox is capable of analyzing data from many different types of recording modalities, and we give examples of how it can be used to decode basic visual information from neural spiking activity and how it can be used to examine how invariant the activity of a neural population is to stimulus transformations. Overall this toolbox will make it much easier for neuroscientists to apply population decoding analyses to their data, which should help increase the pace of discovery in neuroscience.

  19. A restricted test of single word intelligibility in 3-year-old children with and without cleft palate

    DEFF Research Database (Denmark)

    Willadsen, Elisabeth; Poulsen, Mads

    2012-01-01

    listeners to understand. The error of retraction/backing of alveolar target consonants to velar place of articulation occurred frequently and most often in the HPU group and was found to have a negative effect on intelligibility. Key words: intelligibility, cleft palate, naïve listeners, error types, single...

  20. Investigating single-word syntactic primes in naming tasks: a recurrent network approach.

    Science.gov (United States)

    Farrar, W T

    1998-04-01

    Three experiments compared the qualitative pattern of participants' word-naming performance in a syntactic priming task with the qualitative pattern of performance generated by a recurrent network model. Experiments 1 and 2 demonstrated that when participants had a 600-ms response deadline, the appropriateness of a syntactic prime affected their naming times for high-frequency words but not low-frequency words. However, Experiment 2 also demonstrated that participants made the most pronunciation errors when naming inconsistent low-frequency words (e.g., pint) that were preceded by an inappropriate prime. The results of Experiment 3 suggest that participants' naming times to both high- and low-frequency words are affected by syntactic primes when there is no response deadline. The implication of these findings for the study of syntactic priming in English and other languages is discussed.

  1. Decoding communities in networks

    Science.gov (United States)

    Radicchi, Filippo

    2018-02-01

    According to a recent information-theoretical proposal, the problem of defining and identifying communities in networks can be interpreted as a classical communication task over a noisy channel: memberships of nodes are information bits erased by the channel, edges and nonedges in the network are parity bits introduced by the encoder but degraded through the channel, and a community identification algorithm is a decoder. The interpretation is perfectly equivalent to the one at the basis of well-known statistical inference algorithms for community detection. The only difference in the interpretation is that a noisy channel replaces a stochastic network model. However, the different perspective gives the opportunity to take advantage of the rich set of tools of coding theory to generate novel insights on the problem of community detection. In this paper, we illustrate two main applications of standard coding-theoretical methods to community detection. First, we leverage a state-of-the-art decoding technique to generate a family of quasioptimal community detection algorithms. Second and more important, we show that the Shannon's noisy-channel coding theorem can be invoked to establish a lower bound, here named as decodability bound, for the maximum amount of noise tolerable by an ideal decoder to achieve perfect detection of communities. When computed for well-established synthetic benchmarks, the decodability bound explains accurately the performance achieved by the best community detection algorithms existing on the market, telling us that only little room for their improvement is still potentially left.

  2. A restricted test of single word intelligibility in 3-year-old children with and without cleft palate

    DEFF Research Database (Denmark)

    Willadsen, Elisabeth; Poulsen, Mads

    2012-01-01

    Abstract Objective: In a previous study, children with cleft palate with hard palate closure at 12 months of age showed more typical phonological development than children with an unrepaired hard palate at 36 months of age. This finding was based on narrow transcription of word initial target...... listeners to understand. The error of retraction/backing of alveolar target consonants to velar place of articulation occurred frequently and most often in the HPU group and was found to have a negative effect on intelligibility. Key words: intelligibility, cleft palate, naïve listeners, error types, single...... hard palate closure at either12 months (HPR (hard palate repaired)) or 36 months (HPU (hard palate unrepaired)), were compared to data obtained from 14 age-matched, typically developing, control children. Methods: Video recordings of the children naming target words were shown to 84 naïve listeners...

  3. Single dose antidepressant administration modulates the neural processing of self-referent personality trait words

    DEFF Research Database (Denmark)

    Miskowiak, Kamilla; Papadatou-Pastou, Marietta; Cowen, Philip J

    2007-01-01

    categorisation and recognition of self-referent personality trait words were assessed using event-related functional Magnetic Resonance Imaging (fMRI). Reboxetine had no effect on neuronal response during self-referent categorisation of positive or negative personality trait words. However, in a subsequent...... memory test, reboxetine reduced neuronal activation in a fronto-parietal network during correct recognition of positive target words vs. matched distractors. This was combined with increased speed to recognize positive vs. negative words compared to control subjects and suggests facilitated memory...... for positive self-referent material. These results support the hypothesis that antidepressants have early effects on the neural processing of emotional material which may be important in their therapeutic actions....

  4. Brain-to-text: Decoding spoken phrases from phone representations in the brain

    Directory of Open Access Journals (Sweden)

    Christian eHerff

    2015-06-01

    Full Text Available It has long been speculated whether communication between humans and machines based on natural speech related cortical activity is possible. Over the past decade, studies have suggested that it is feasible to recognize isolated aspects of speech from neural signals, such as auditory features, phones or one of a few isolated words. However, until now it remained an unsolved challenge to decode continuously spoken speech from the neural substrate associated with speech and language processing. Here, we show for the first time that continuously spoken speech can be decoded into the expressed words from intracranial electrocorticographic (ECoG recordings. Specifically, we implemented a system, which we call Brain-To-Text that models single phones, employs techniques from automatic speech recognition (ASR, and thereby transforms brain activity while speaking into the corresponding textual representation. Our results demonstrate that our system achieved word error rates as low as 25% and phone error rates below 50%. Additionally, our approach contributes to the current understanding of the neural basis of continuous speech production by identifying those cortical regions that hold substantial information about individual phones. In conclusion, the Brain-To-Text system described in this paper represents an important step towards human-machine communication based on imagined speech.

  5. Comparison of single-word and adjective-noun phrase production using event-related brain potentials

    DEFF Research Database (Denmark)

    Lange, Violaine Michel

    2015-01-01

    in a time-window extending beyond early visual analysis. In a second experiment, different participants were asked to produce either single noun or adjective-noun dual-word phrases to black-and-white and coloured line drawings, respectively. Adjective-noun phrase production (2W) resulted in naming latencies...... stimuli varying in complexity -black and white line drawings, coloured line drawings, and arrays of drawings-in participants producing single nouns. Whilst naming latencies were similar for single noun production between visual stimuli conditions, ERPs differed between drawing arrays and single drawings...... 53 msec longer than single noun (1W) production. Waveform amplitude and topographic analyses carried out on stimulus- and response-aligned ERPs indicated that the two conditions differed in a late time-window, with a topographic pattern for 2W lasting from 300 to 480 msec after picture presentation...

  6. Decoding Codes on Graphs

    Indian Academy of Sciences (India)

    set up a well defined goal - that of achieving a per- formance bound set by the noisy channel coding theo- rem, proved in the paper. Whereas the goal appeared elusive twenty five years ago, today, there are practi- cal codes and decoding algorithms that come close to achieving it. It is interesting to note that all known.

  7. Decoding Codes on Graphs

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 9. Decoding Codes on Graphs - Low Density Parity Check Codes. A S Madhu Aditya Nori. General Article Volume 8 Issue 9 September 2003 pp 49-59. Fulltext. Click here to view fulltext PDF. Permanent link:

  8. Deep generative learning of location-invariant visual word recognition

    Science.gov (United States)

    Di Bono, Maria Grazia; Zorzi, Marco

    2013-01-01

    It is widely believed that orthographic processing implies an approximate, flexible coding of letter position, as shown by relative-position and transposition priming effects in visual word recognition. These findings have inspired alternative proposals about the representation of letter position, ranging from noisy coding across the ordinal positions to relative position coding based on open bigrams. This debate can be cast within the broader problem of learning location-invariant representations of written words, that is, a coding scheme abstracting the identity and position of letters (and combinations of letters) from their eye-centered (i.e., retinal) locations. We asked whether location-invariance would emerge from deep unsupervised learning on letter strings and what type of intermediate coding would emerge in the resulting hierarchical generative model. We trained a deep network with three hidden layers on an artificial dataset of letter strings presented at five possible retinal locations. Though word-level information (i.e., word identity) was never provided to the network during training, linear decoding from the activity of the deepest hidden layer yielded near-perfect accuracy in location-invariant word recognition. Conversely, decoding from lower layers yielded a large number of transposition errors. Analyses of emergent internal representations showed that word selectivity and location invariance increased as a function of layer depth. Word-tuning and location-invariance were found at the level of single neurons, but there was no evidence for bigram coding. Finally, the distributed internal representation of words at the deepest layer showed higher similarity to the representation elicited by the two exterior letters than by other combinations of two contiguous letters, in agreement with the hypothesis that word edges have special status. These results reveal that the efficient coding of written words—which was the model's learning objective

  9. Transfer of decoding skills in early foreign language reading

    NARCIS (Netherlands)

    Ven, M.A.M. van de; Voeten, M.J.M.; Steenbeek-Planting, E.G.; Verhoeven, L.T.W.

    2018-01-01

    This longitudinal study investigated cross-linguistic transfer from native to foreign language decoding abilities in 787 Dutch first-year students in two differential tracks (high vs low) of secondary education. On two occasions, with a six months interval, we tested the students' word and

  10. Decoding by dynamic chunking for statistical machine translation

    NARCIS (Netherlands)

    Yahyaei, S.; Monz, C.; Gerber, L.; Isabelle, P.; Kuhn, R.; Bemish, N.; Dillinger, M.; Goulet, M.-J.

    2009-01-01

    In this paper we present an extension of a phrase-based decoder that dynamically chunks, reorders, and applies phrase translations in tandem. A maximum entropy classifier is trained based on the word alignments to find the best positions to chunk the source sentence. No language specific or

  11. Is "hit and run" a single word? The processing of irreversible binomials in neglect dyslexia.

    Science.gov (United States)

    Arcara, Giorgio; Lacaita, Graziano; Mattaloni, Elisa; Passarini, Laura; Mondini, Sara; Benincà, Paola; Semenza, Carlo

    2012-01-01

    The present study is the first neuropsychological investigation into the problem of the mental representation and processing of irreversible binomials (IBs), i.e., word pairs linked by a conjunction (e.g., "hit and run," "dead or alive"). In order to test their lexical status, the phenomenon of neglect dyslexia is explored. People with left-sided neglect dyslexia show a clear lexical effect: they can read IBs better (i.e., by dropping the leftmost words less frequently) when their components are presented in their correct order. This may be taken as an indication that they treat these constructions as lexical, not decomposable, elements. This finding therefore constitutes strong evidence that IBs tend to be stored in the mental lexicon as a whole and that this whole form is preferably addressed in the retrieval process.

  12. Forced Sequence Sequential Decoding

    DEFF Research Database (Denmark)

    Jensen, Ole Riis

    is possible as low as Eb/No=0.6 dB, which is about 1.7 dB below the signal-to-noise ratio that marks the cut-off rate for the convolutional code. This is possible since the iteration process provides the sequential decoders with side information that allows a smaller average load and minimizes the probability...

  13. Decoding the human genome

    CERN Document Server

    CERN. Geneva. Audiovisual Unit; Antonerakis, S E

    2002-01-01

    Decoding the Human genome is a very up-to-date topic, raising several questions besides purely scientific, in view of the two competing teams (public and private), the ethics of using the results, and the fact that the project went apparently faster and easier than expected. The lecture series will address the following chapters: Scientific basis and challenges. Ethical and social aspects of genomics.

  14. Single-Word Predictions of Upcoming Language During Comprehension: Evidence from the Cumulative Semantic Interference Task

    Science.gov (United States)

    Kleinman, Daniel; Runnqvist, Elin; Ferreira, Victor S.

    2015-01-01

    Comprehenders predict upcoming speech and text on the basis of linguistic input. How many predictions do comprehenders make for an upcoming word? If a listener strongly expects to hear the word “sock”, is the word “shirt” partially expected as well, is it actively inhibited, or is it ignored? The present research addressed these questions by measuring the “downstream” effects of prediction on the processing of subsequently presented stimuli using the cumulative semantic interference paradigm. In three experiments, subjects named pictures (sock) that were presented either in isolation or after strongly constraining sentence frames (“After doing his laundry, Mark always seemed to be missing one…”). Naming sock slowed the subsequent naming of the picture shirt – the standard cumulative semantic interference effect. However, although picture naming was much faster after sentence frames, the interference effect was not modulated by the context (bare vs. sentence) in which either picture was presented. According to the only model of cumulative semantic interference that can account for such a pattern of data, this indicates that comprehenders pre-activated and maintained the pre-activation of best sentence completions (sock) but did not maintain the pre-activation of less likely completions (shirt). Thus, comprehenders predicted only the most probable completion for each sentence. PMID:25917550

  15. Stochastic Decoding of Turbo Codes

    OpenAIRE

    Dong , Q. T.; ARZEL , Matthieu; Jego , Christophe; Gross , W. J.

    2010-01-01

    International audience; Stochastic computation is a technique in which operations on probabilities are performed on random bit streams. Stochastic decoding of forward error-correction (FEC) codes is inspired by this technique. This paper extends the application of the stochastic decoding approach to the families of convolutional codes and turbo codes. It demonstrates that stochastic computation is a promising solution to improve the data throughput of turbo decoders with very simple implement...

  16. Design of FBG En/decoders in Coherent 2-D Time-polarization OCDMA Systems

    Science.gov (United States)

    Hou, Fen-fei; Yang, Ming

    2012-12-01

    A novel fiber Bragg grating (FBG)-based en/decoder for the two-dimensional (2-D) time-spreading and polarization multiplexer optical coding is proposed. Compared with other 2-D en/decoders, the proposed en/decoding for an optical code-division multiple-access (OCDMA) system uses a single phase-encoded FBG and coherent en/decoding. Furthermore, combined with reconstruction-equivalent-chirp technology, such en/decoders can be realized with a conventional simple fabrication setup. Experimental results of such en/decoders and the corresponding system test at a data rate of 5 Gbit/s demonstrate that this kind of 2-D FBG-based en/decoders could improve the performances of OCDMA systems.

  17. 47 CFR 11.33 - EAS Decoder.

    Science.gov (United States)

    2010-10-01

    ... input. (8) Decoder Programming. Access to decoder programming shall be protected by a lock or other... Decoder with preselected Originator, Event and Location codes for either manual or automatic operation. (9...

  18. Decoding the productivity code

    DEFF Research Database (Denmark)

    Hansen, David

    , that is, the productivity code of the 21st century, is dissolved. Today, organizations are pressured for operational efficiency, often in terms of productivity, due to increased global competition, demographical changes, and use of natural resources. Taylor’s principles for rationalization founded...... that swing between rationalization and employee development. The productivity code is the lack of alternatives to this ineffective approach. This thesis decodes the productivity code based on the results from a 3-year action research study at a medium-sized manufacturing facility. During the project period...

  19. The Effects of Visual Attention Span and Phonological Decoding in Reading Comprehension in Dyslexia: A Path Analysis.

    Science.gov (United States)

    Chen, Chen; Schneps, Matthew H; Masyn, Katherine E; Thomson, Jennifer M

    2016-11-01

    Increasing evidence has shown visual attention span to be a factor, distinct from phonological skills, that explains single-word identification (pseudo-word/word reading) performance in dyslexia. Yet, little is known about how well visual attention span explains text comprehension. Observing reading comprehension in a sample of 105 high school students with dyslexia, we used a pathway analysis to examine the direct and indirect path between visual attention span and reading comprehension while controlling for other factors such as phonological awareness, letter identification, short-term memory, IQ and age. Integrating phonemic decoding efficiency skills in the analytic model, this study aimed to disentangle how visual attention span and phonological skills work together in reading comprehension for readers with dyslexia. We found visual attention span to have a significant direct effect on more difficult reading comprehension but not on an easier level. It also had a significant direct effect on pseudo-word identification but not on word identification. In addition, we found that visual attention span indirectly explains reading comprehension through pseudo-word reading and word reading skills. This study supports the hypothesis that at least part of the dyslexic profile can be explained by visual attention abilities. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  20. From orthography to meaning: an electrophysiological investigation of the role of phonology in accessing meaning of Chinese single-character words.

    Science.gov (United States)

    Wang, K; Mecklinger, A; Hofmann, J; Weng, X

    2010-01-13

    Homophone interference effects in Stroop experiments are often taken as evidence for the hypothesis that semantic access in written Chinese language is mediated by activation of phonological processing. We here aim to test this hypothesis with Chinese single-character words by means of event related potential (ERP) recordings. Using color words, homophones of color words and color-word associates as materials in a Stroop task, we found behavioral Stroop interference effects for all stimulus types and an N450 for incongruent color words and color-word associates. Critically, there was no difference in the ERP waveforms elicited by congruent and incongruent homophones in the N450 time window. However, in a later time window (600-800 ms) the incongruent homophones elicited an apparent positivity over left posterior regions. A similar effect was also observed for incongruent color words. These findings thus indicate that phonology does not play an important role in semantic activation of Chinese single-character words, and that the behavioral Stroop effects for homophones possibly arises at later stage of lexical processing.

  1. Lexical decoder for continuous speech recognition: sequential neural network approach

    International Nuclear Information System (INIS)

    Iooss, Christine

    1991-01-01

    The work presented in this dissertation concerns the study of a connectionist architecture to treat sequential inputs. In this context, the model proposed by J.L. Elman, a recurrent multilayers network, is used. Its abilities and its limits are evaluated. Modifications are done in order to treat erroneous or noisy sequential inputs and to classify patterns. The application context of this study concerns the realisation of a lexical decoder for analytical multi-speakers continuous speech recognition. Lexical decoding is completed from lattices of phonemes which are obtained after an acoustic-phonetic decoding stage relying on a K Nearest Neighbors search technique. Test are done on sentences formed from a lexicon of 20 words. The results are obtained show the ability of the proposed connectionist model to take into account the sequentiality at the input level, to memorize the context and to treat noisy or erroneous inputs. (author) [fr

  2. Decoding temporally encoded sensory input by cortical oscillations and thalamic phase comparators

    OpenAIRE

    Ahissar, Ehud; Haidarliu, Sebastian; Zacksenhouse, Miriam

    1997-01-01

    The temporally encoded information obtained by vibrissal touch could be decoded “passively,” involving only input-driven elements, or “actively,” utilizing intrinsically driven oscillators. A previous study suggested that the trigeminal somatosensory system of rats does not obey the bottom-up order of activation predicted by passive decoding. Thus, we have tested whether this system obeys the predictions of active decoding. We have studied cortical single units in ...

  3. Astrophysics Decoding the cosmos

    CERN Document Server

    Irwin, Judith A

    2007-01-01

    Astrophysics: Decoding the Cosmos is an accessible introduction to the key principles and theories underlying astrophysics. This text takes a close look at the radiation and particles that we receive from astronomical objects, providing a thorough understanding of what this tells us, drawing the information together using examples to illustrate the process of astrophysics. Chapters dedicated to objects showing complex processes are written in an accessible manner and pull relevant background information together to put the subject firmly into context. The intention of the author is that the book will be a 'tool chest' for undergraduate astronomers wanting to know the how of astrophysics. Students will gain a thorough grasp of the key principles, ensuring that this often-difficult subject becomes more accessible.

  4. How Many Pages in a Single Word: Alternative Typo-poetics of Surrealist Magazines

    Directory of Open Access Journals (Sweden)

    Biljana Andonovska

    2013-07-01

    Full Text Available The paper examines the experimental design, typography and editorial strategies of the rare avant-garde publication Four Pages - Onanism of Death - And So On (1930, published by Oskar Davičo, Đorđe Kostić and Đorđe Jovanović, probably the first Surrealist Edition of the Belgrade surrealist group. Starting from its unconventional format and the way authors (reshape and (misdirect each page in an autonomous fashion, I further analyze the intrinsic interaction between the text, its graphic embodiment and surrounding para-textual elements (illustrations, body text, titles, folding, dating, margins, comments. Special attention is given to the concepts of depersonalization, free association and automatic writing as primary poetical sources for the delinearisation of the reading process and 'emancipation' of the text, its content and syntax as well as its position, direction, and visual materiality on the page. Resisting conventional classifications and simplified distinctions between established print media and genres, this surrealist single-issue placard magazine mixes elements of the poster, magazine, and booklet. Its ambiguous nature leads us toward theoretical discussion of the avant-garde magazine as an autonomous literary genre and original, self-sufficient artwork, as was already suggested by the theory of Russian formalism.

  5. Modelling reading development through phonological decoding and self-teaching: implications for dyslexia.

    Science.gov (United States)

    Ziegler, Johannes C; Perry, Conrad; Zorzi, Marco

    2014-01-01

    The most influential theory of learning to read is based on the idea that children rely on phonological decoding skills to learn novel words. According to the self-teaching hypothesis, each successful decoding encounter with an unfamiliar word provides an opportunity to acquire word-specific orthographic information that is the foundation of skilled word recognition. Therefore, phonological decoding acts as a self-teaching mechanism or 'built-in teacher'. However, all previous connectionist models have learned the task of reading aloud through exposure to a very large corpus of spelling-sound pairs, where an 'external' teacher supplies the pronunciation of all words that should be learnt. Such a supervised training regimen is highly implausible. Here, we implement and test the developmentally plausible phonological decoding self-teaching hypothesis in the context of the connectionist dual process model. In a series of simulations, we provide a proof of concept that this mechanism works. The model was able to acquire word-specific orthographic representations for more than 25 000 words even though it started with only a small number of grapheme-phoneme correspondences. We then show how visual and phoneme deficits that are present at the outset of reading development can cause dyslexia in the course of reading development.

  6. A Fully Parallel VLSI-implementation of the Viterbi Decoding Algorithm

    DEFF Research Database (Denmark)

    Sparsø, Jens; Jørgensen, Henrik Nordtorp; Paaske, Erik

    1989-01-01

    In this paper we describe the implementation of a K = 7, R = 1/2 single-chip Viterbi decoder intended to operate at 10-20 Mbit/sec. We propose a general, regular and area efficient floor-plan that is also suitable for implementation of decoders for codes with different generator polynomials or di...

  7. Decoding ChIP-seq with a double-binding signal refines binding peaks to single-nucleotides and predicts cooperative interaction

    Science.gov (United States)

    Gomes, Antonio L.C.; Abeel, Thomas; Peterson, Matthew; Azizi, Elham; Lyubetskaya, Anna; Carvalho, Luís

    2014-01-01

    The comprehension of protein and DNA binding in vivo is essential to understand gene regulation. Chromatin immunoprecipitation followed by sequencing (ChIP-seq) provides a global map of the regulatory binding network. Most ChIP-seq analysis tools focus on identifying binding regions from coverage enrichment. However, less work has been performed to infer the physical and regulatory details inside the enriched regions. This research extends a previous blind-deconvolution approach to develop a post-peak–calling algorithm that improves binding site resolution and predicts cooperative interactions. At the core of our new method is a physically motivated model that characterizes the binding signal as an extreme value distribution. This model suggests a mathematical framework to study physical properties of DNA shearing from the ChIP-seq coverage. The model explains the ChIP-seq coverage with two signals: The first considers DNA fragments with only a single binding event, whereas the second considers fragments with two binding events (a double-binding signal). The model incorporates motif discovery and is able to detect multiple sites in an enriched region with single-nucleotide resolution, high sensitivity, and high specificity. Our method improves peak caller sensitivity, from less than 45% up to 94%, at a false positive rate ChIP-seq analysis: the identification of cooperative interaction. Predictions of known cooperative binding sites show a 0.85 area under an ROC curve. PMID:25024162

  8. Some words on Word

    NARCIS (Netherlands)

    Janssen, Maarten; Visser, A.

    In many disciplines, the notion of a word is of central importance. For instance, morphology studies le mot comme tel, pris isol´ement (Mel’ˇcuk, 1993 [74]). In the philosophy of language the word was often considered to be the primary bearer of meaning. Lexicography has as its fundamental role

  9. Deconstructing phonological tasks: The contribution of stimulus and response type to the prediction of early decoding skills.

    Science.gov (United States)

    Cunningham, Anna J; Witton, Caroline; Talcott, Joel B; Burgess, Adrian P; Shapiro, Laura R

    2015-10-01

    Phonological tasks are highly predictive of reading development but their complexity obscures the underlying mechanisms driving this association. There are three key components hypothesised to drive the relationship between phonological tasks and reading; (a) the linguistic nature of the stimuli, (b) the phonological complexity of the stimuli, and (c) the production of a verbal response. We isolated the contribution of the stimulus and response components separately through the creation of latent variables to represent specially designed tasks that were matched for procedure. These tasks were administered to 570 6 to 7-year-old children along with standardised tests of regular word and non-word reading. A structural equation model, where tasks were grouped according to stimulus, revealed that the linguistic nature and the phonological complexity of the stimulus predicted unique variance in decoding, over and above matched comparison tasks without these components. An alternative model, grouped according to response mode, showed that the production of a verbal response was a unique predictor of decoding beyond matched tasks without a verbal response. In summary, we found that multiple factors contributed to reading development, supporting multivariate models over those that prioritize single factors. More broadly, we demonstrate the value of combining matched task designs with latent variable modelling to deconstruct the components of complex tasks. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  10. EEG source imaging assists decoding in a face recognition task

    DEFF Research Database (Denmark)

    Andersen, Rasmus S.; Eliasen, Anders U.; Pedersen, Nicolai

    2017-01-01

    of face recognition. This task concerns the differentiation of brain responses to images of faces and scrambled faces and poses a rather difficult decoding problem at the single trial level. We implement the pipeline using spatially focused features and show that this approach is challenged and source...

  11. Trellises and Trellis-Based Decoding Algorithms for Linear Block Codes

    Science.gov (United States)

    Lin, Shu

    1998-01-01

    sectionalization of trellises. Chapter 7 discusses trellis decomposition and subtrellises for low-weight codewords. Chapter 8 first presents well known methods for constructing long powerful codes from short component codes or component codes of smaller dimensions, and then provides methods for constructing their trellises which include Shannon and Cartesian product techniques. Chapter 9 deals with convolutional codes, puncturing, zero-tail termination and tail-biting.Chapters 10 through 13 present various trellis-based decoding algorithms, old and new. Chapter 10 first discusses the application of the well known Viterbi decoding algorithm to linear block codes, optimum sectionalization of a code trellis to minimize computation complexity, and design issues for IC (integrated circuit) implementation of a Viterbi decoder. Then it presents a new decoding algorithm for convolutional codes, named Differential Trellis Decoding (DTD) algorithm. Chapter 12 presents a suboptimum reliability-based iterative decoding algorithm with a low-weight trellis search for the most likely codeword. This decoding algorithm provides a good trade-off between error performance and decoding complexity. All the decoding algorithms presented in Chapters 10 through 12 are devised to minimize word error probability. Chapter 13 presents decoding algorithms that minimize bit error probability and provide the corresponding soft (reliability) information at the output of the decoder. Decoding algorithms presented are the MAP (maximum a posteriori probability) decoding algorithm and the Soft-Output Viterbi Algorithm (SOVA) algorithm. Finally, the minimization of bit error probability in trellis-based MLD is discussed.

  12. Real-time MPEG-1 software decoding on HP workstations

    Science.gov (United States)

    Bhaskaran, Vasudev; Konstantinides, Konstantinos; Lee, Ruby B.

    1995-04-01

    A MPEG1 codec that is capable of real-time playback of video and audio on HP's RISC-based workstations has been developed. Real-time playback is achieved by examining the complete MPEG1 decoding pipeline and optimizing the algorithms used for the various stages of the video and audio decompression process. For video decompression, efficient implementations are derived by examining the huffman decoder, inverse quantizer and inverse DCT as a single system. For audio decompression, by viewing the subband synthesis function in MPEG1 layer I and layer II decoding as a DCT, a fast 32-point DCT suitable for use in MPEG1 audio decompression has been developed. Besides algorithmic enhancements, in order to achieve real-time performance, minor changes to the CPU architecture and the display pipeline architecture were needed. The integration of algorithmic and architectural enhancements results in real-time playback of MPEG1 video and audio on HP's RISC based workstations.

  13. Contributions of Phonological Awareness, Phonological Short-Term Memory, and Rapid Automated Naming, toward Decoding Ability in Students with Mild Intellectual Disability

    Science.gov (United States)

    Soltani, Amanallah; Roslan, Samsilah

    2013-01-01

    Reading decoding ability is a fundamental skill to acquire word-specific orthographic information necessary for skilled reading. Decoding ability and its underlying phonological processing skills have been heavily investigated typically among developing students. However, the issue has rarely been noticed among students with intellectual…

  14. Increased motor preparation activity during fluent single word production in DS: A correlate for stuttering frequency and severity.

    Science.gov (United States)

    Vanhoutte, Sarah; Santens, Patrick; Cosyns, Marjan; van Mierlo, Pieter; Batens, Katja; Corthals, Paul; De Letter, Miet; Van Borsel, John

    2015-08-01

    Abnormal speech motor preparation is suggested to be a neural characteristic of stuttering. One of the neurophysiological substrates of motor preparation is the contingent negative variation (CNV). The CNV is an event-related, slow negative potential that occurs between two defined stimuli. Unfortunately, CNV tasks are rarely studied in developmental stuttering (DS). Therefore, the present study aimed to evaluate motor preparation in DS by use of a CNV task. Twenty five adults who stutter (AWS) and 35 fluent speakers (FS) were included. They performed a picture naming task while an electro-encephalogram was recorded. The slope of the CNV was evaluated at frontal, central and parietal electrode sites. In addition, a correlation analysis was performed with stuttering severity and frequency measures. There was a marked increase in CNV slope in AWS as compared to FS. This increase was observed over the entire scalp with respect to stimulus onset, and only over the right hemisphere with respect to lip movement onset. Moreover, strong positive correlations were found between CNV slope and stuttering frequency and severity. As the CNV is known to reflect the activity in the basal ganglia-thalamo-cortical-network, the present findings confirm an increased activation of this loop during speech motor preparation in stuttering. The more a person stutters, the more neurons of this cortical-subcortical network seem to be activated. Because this increased CNV slope was observed during fluent single word production, it is discussed whether or not this observation refers to a successful compensation strategy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. On Decoding Interleaved Chinese Remainder Codes

    DEFF Research Database (Denmark)

    Li, Wenhui; Sidorenko, Vladimir; Nielsen, Johan Sebastian Rosenkilde

    2013-01-01

    We model the decoding of Interleaved Chinese Remainder codes as that of finding a short vector in a Z-lattice. Using the LLL algorithm, we obtain an efficient decoding algorithm, correcting errors beyond the unique decoding bound and having nearly linear complexity. The algorithm can fail...

  16. Encoding and Decoding Models in Cognitive Electrophysiology.

    Science.gov (United States)

    Holdgraf, Christopher R; Rieger, Jochem W; Micheli, Cristiano; Martin, Stephanie; Knight, Robert T; Theunissen, Frederic E

    2017-01-01

    Cognitive neuroscience has seen rapid growth in the size and complexity of data recorded from the human brain as well as in the computational tools available to analyze this data. This data explosion has resulted in an increased use of multivariate, model-based methods for asking neuroscience questions, allowing scientists to investigate multiple hypotheses with a single dataset, to use complex, time-varying stimuli, and to study the human brain under more naturalistic conditions. These tools come in the form of "Encoding" models, in which stimulus features are used to model brain activity, and "Decoding" models, in which neural features are used to generated a stimulus output. Here we review the current state of encoding and decoding models in cognitive electrophysiology and provide a practical guide toward conducting experiments and analyses in this emerging field. Our examples focus on using linear models in the study of human language and audition. We show how to calculate auditory receptive fields from natural sounds as well as how to decode neural recordings to predict speech. The paper aims to be a useful tutorial to these approaches, and a practical introduction to using machine learning and applied statistics to build models of neural activity. The data analytic approaches we discuss may also be applied to other sensory modalities, motor systems, and cognitive systems, and we cover some examples in these areas. In addition, a collection of Jupyter notebooks is publicly available as a complement to the material covered in this paper, providing code examples and tutorials for predictive modeling in python. The aim is to provide a practical understanding of predictive modeling of human brain data and to propose best-practices in conducting these analyses.

  17. Improved decoding for a concatenated coding system

    DEFF Research Database (Denmark)

    Paaske, Erik

    1990-01-01

    The concatenated coding system recommended by CCSDS (Consultative Committee for Space Data Systems) uses an outer (255,233) Reed-Solomon (RS) code based on 8-b symbols, followed by the block interleaver and an inner rate 1/2 convolutional code with memory 6. Viterbi decoding is assumed. Two new...... decoding procedures based on repeated decoding trials and exchange of information between the two decoders and the deinterleaver are proposed. In the first one, where the improvement is 0.3-0.4 dB, only the RS decoder performs repeated trials. In the second one, where the improvement is 0.5-0.6 dB, both...

  18. FPGA Realization of Memory 10 Viterbi Decoder

    DEFF Research Database (Denmark)

    Paaske, Erik; Bach, Thomas Bo; Andersen, Jakob Dahl

    1997-01-01

    A feasibility study for a low cost, iterative, serially concatenated coding system is performed. The system uses outer (255,223) Reed-Solomon codes and convolutional inner codes with memory 10 and rates 1/4 or 1/6. The corresponding inner decoder is a Viterbi decoder, which can operate in a forced...... sequence mode when feedback from the Reed-Solomon decoder is available. The Viterbi decoder is realized using two Altera FLEX 10K50 FPGA's. The overall operating speed is 30 kbit/s, and since up to three iterations are performed for each frame and only one decoder is used, the operating speed...

  19. Manchester encoder-decoder for optical data communication links.

    Science.gov (United States)

    Al-Sammak, A J; Al-Ruwaihi, K; Al-Kooheji, I

    1992-04-20

    A new encoder-decoder (CODEC) design of a Manchester coding scheme suitable for optical data communication links is presented. The design is simple and uses off-the-shelf digital electronic components and subsystems. The CODEC can be used for high data rate transmissions, typical of opticalfiber systems and local area networks. The decoder is insensitive to variations in the clock rates within the range of +/-33%, whereas the encoder, which is a simple XOR logic gate, is not affected by clock variations. During high-frequency operation (e.g., at 100 MHz), the CODEC can be operated at a wide range of frequencies (from 66.6 to 133.3 MHz) without modification to the CODEC circuitry. Furthermore, the CODEC can be made to operate at any data rate by a simple change of a single capacitor or a single resistor in the decoder circuit. The CODEC was built in the laboratory by using transistor-transistor logicintegrated circuits. It was experimentally found that with this decoder the transmitted data, as well as the cloc, can be recovered from the Manchester coded signal without being affected by clock variations within the designed range.

  20. Elegant grapheme-phoneme correspondence: a periodic chart and singularity generalization unify decoding.

    Science.gov (United States)

    Gates, Louis

    2017-12-11

    The accompanying article introduces highly transparent grapheme-phoneme relationships embodied within a Periodic table of decoding cells, which arguably presents the quintessential transparent decoding elements. The study then folds these cells into one highly transparent but simply stated singularity generalization-this generalization unifies the decoding cells (97% transparency). Deeper, the periodic table and singularity generalization together highlight the connectivity of the periodic cells. Moreover, these interrelated cells, coupled with the singularity generalization, clarify teaching targets and enable efficient learning of the letter-sound code. This singularity generalization, in turn, serves as a model for creating unified but easily stated subordinate generalizations for any one of the transparent cells or groups of cells shown within the tables. The article then expands the periodic cells into two tables of teacher-ready sample word lists-one table includes sample words for the basic and phonogram vowel cells, and the other table embraces word samples for the transparent consonant cells. The paper concludes with suggestions for teaching the cellular transparency embedded within reoccurring isolated words and running text to promote decoding automaticity of the periodic cells.

  1. The Effects of Musical Training on the Decoding Skills of German-Speaking Primary School Children

    Science.gov (United States)

    Rautenberg, Iris

    2015-01-01

    This paper outlines the results of a long-term study of 159 German-speaking primary school children. The correlations between musical skills (perception and differentiation of rhythmical and tonal/melodic patterns) and decoding skills, and the effects of musical training on word-level reading abilities were investigated. Cognitive skills and…

  2. Orthographic Context Sensitivity in Vowel Decoding by Portuguese Monolingual and Portuguese-English Bilingual Children

    Science.gov (United States)

    Vale, Ana Paula

    2011-01-01

    This study examines the pronunciation of the first vowel in decoding disyllabic pseudowords derived from Portuguese words. Participants were 96 Portuguese monolinguals and 52 Portuguese-English bilinguals of equivalent Portuguese reading levels. The results indicate that sensitivity to vowel context emerges early, both in monolinguals and in…

  3. Scaffolding Students’ Independent Decoding of Unfamiliar Text with a Prototype of an eBook-Feature

    DEFF Research Database (Denmark)

    Gissel, Stig Toke

    2015-01-01

    This study was undertaken to design, evaluate and refine an eBook-feature that supports students' decoding of unfamiliar text. The feature supports students' independent reading of eBooks with text-to-speech, graded support in the form of syllabification and rhyme analogy, and by dividing the word...

  4. Sum of the Magnitude for Hard Decision Decoding Algorithm Based on Loop Update Detection

    Directory of Open Access Journals (Sweden)

    Jiahui Meng

    2018-01-01

    Full Text Available In order to improve the performance of non-binary low-density parity check codes (LDPC hard decision decoding algorithm and to reduce the complexity of decoding, a sum of the magnitude for hard decision decoding algorithm based on loop update detection is proposed. This will also ensure the reliability, stability and high transmission rate of 5G mobile communication. The algorithm is based on the hard decision decoding algorithm (HDA and uses the soft information from the channel to calculate the reliability, while the sum of the variable nodes’ (VN magnitude is excluded for computing the reliability of the parity checks. At the same time, the reliability information of the variable node is considered and the loop update detection algorithm is introduced. The bit corresponding to the error code word is flipped multiple times, before this is searched in the order of most likely error probability to finally find the correct code word. Simulation results show that the performance of one of the improved schemes is better than the weighted symbol flipping (WSF algorithm under different hexadecimal numbers by about 2.2 dB and 2.35 dB at the bit error rate (BER of 10−5 over an additive white Gaussian noise (AWGN channel, respectively. Furthermore, the average number of decoding iterations is significantly reduced.

  5. Is ‘hit and run’ a single word? The processing of irreversible binomials in neglect dyslexia

    Directory of Open Access Journals (Sweden)

    Giorgio eArcara

    2012-02-01

    Full Text Available The present study is the first neuropsychological investigation into the problem of the mental representation and processing of irreversible binomials, i.e. word pairs linked by a conjunction (e.g. ‘hit and run’, ‘dead or alive’. In order to test their lexical status, the phenomenon of neglect dyslexia is explored.People with left-sided neglect dyslexia show a clear lexical effect: they can read irreversible binomials better (i.e., by dropping the leftmost words less frequently when their components are presented in their correct order. This may be taken as an indication that they treat these constructions as lexical, not decomposable, elements. This finding therefore constitutes strong evidence that irreversible binomials tend to be stored in the mental lexicon as a whole and that this whole form is preferably addressed in the retrieval process.

  6. Is “Hit and Run” a Single Word? The Processing of Irreversible Binomials in Neglect Dyslexia

    Science.gov (United States)

    Arcara, Giorgio; Lacaita, Graziano; Mattaloni, Elisa; Passarini, Laura; Mondini, Sara; Benincà, Paola; Semenza, Carlo

    2012-01-01

    The present study is the first neuropsychological investigation into the problem of the mental representation and processing of irreversible binomials (IBs), i.e., word pairs linked by a conjunction (e.g., “hit and run,” “dead or alive”). In order to test their lexical status, the phenomenon of neglect dyslexia is explored. People with left-sided neglect dyslexia show a clear lexical effect: they can read IBs better (i.e., by dropping the leftmost words less frequently) when their components are presented in their correct order. This may be taken as an indication that they treat these constructions as lexical, not decomposable, elements. This finding therefore constitutes strong evidence that IBs tend to be stored in the mental lexicon as a whole and that this whole form is preferably addressed in the retrieval process. PMID:22347199

  7. Volitional and Real-Time Control Cursor Based on Eye Movement Decoding Using a Linear Decoding Model

    Directory of Open Access Journals (Sweden)

    Jinhua Zhang

    2016-01-01

    Full Text Available The aim of this study is to build a linear decoding model that reveals the relationship between the movement information and the EOG (electrooculogram data to online control a cursor continuously with blinks and eye pursuit movements. First of all, a blink detection method is proposed to reject a voluntary single eye blink or double-blink information from EOG. Then, a linear decoding model of time series is developed to predict the position of gaze, and the model parameters are calibrated by the RLS (Recursive Least Square algorithm; besides, the assessment of decoding accuracy is assessed through cross-validation procedure. Additionally, the subsection processing, increment control, and online calibration are presented to realize the online control. Finally, the technology is applied to the volitional and online control of a cursor to hit the multiple predefined targets. Experimental results show that the blink detection algorithm performs well with the voluntary blink detection rate over 95%. Through combining the merits of blinks and smooth pursuit movements, the movement information of eyes can be decoded in good conformity with the average Pearson correlation coefficient which is up to 0.9592, and all signal-to-noise ratios are greater than 0. The novel system allows people to successfully and economically control a cursor online with a hit rate of 98%.

  8. Interior point decoding for linear vector channels

    International Nuclear Information System (INIS)

    Wadayama, T

    2008-01-01

    In this paper, a novel decoding algorithm for low-density parity-check (LDPC) codes based on convex optimization is presented. The decoding algorithm, called interior point decoding, is designed for linear vector channels. The linear vector channels include many practically important channels such as inter-symbol interference channels and partial response channels. It is shown that the maximum likelihood decoding (MLD) rule for a linear vector channel can be relaxed to a convex optimization problem, which is called a relaxed MLD problem

  9. Word Translation Entropy

    DEFF Research Database (Denmark)

    Schaeffer, Moritz; Dragsted, Barbara; Hvelplund, Kristian Tangsgaard

    This study reports on an investigation into the relationship between the number of translation alternatives for a single word and eye movements on the source text. In addition, the effect of word order differences between source and target text on eye movements on the source text is studied. In p...

  10. Word Translation Entropy

    DEFF Research Database (Denmark)

    Schaeffer, Moritz; Dragsted, Barbara; Hvelplund, Kristian Tangsgaard

    2016-01-01

    This study reports on an investigation into the relationship between the number of translation alternatives for a single word and eye movements on the source text. In addition, the effect of word order differences between source and target text on eye movements on the source text is studied. In p...

  11. On Rational Interpolation-Based List-Decoding and List-Decoding Binary Goppa Codes

    DEFF Research Database (Denmark)

    Beelen, Peter; Høholdt, Tom; Nielsen, Johan Sebastian Rosenkilde

    2013-01-01

    a new application of the Wu list decoder by decoding irreducible binary Goppa codes up to the binary Johnson radius. Finally, we point out a connection between the governing equations of the Wu algorithm and the Guruswami–Sudan algorithm, immediately leading to equality in the decoding range...

  12. Speed and automaticity of word recognition - inseparable twins?

    DEFF Research Database (Denmark)

    Poulsen, Mads; Asmussen, Vibeke; Elbro, Carsten

    'Speed and automaticity' of word recognition is a standard collocation. However, it is not clear whether speed and automaticity (i.e., effortlessness) make independent contributions to reading comprehension. In theory, both speed and automaticity may save cognitive resources for comprehension...... processes. Hence, the aim of the present study was to assess the unique contributions of word recognition speed and automaticity to reading comprehension while controlling for decoding speed and accuracy. Method: 139 Grade 5 students completed tests of reading comprehension and computer-based tests of speed...... of decoding and word recognition together with a test of effortlessness (automaticity) of word recognition. Effortlessness was measured in a dual task in which participants were presented with a word enclosed in an unrelated figure. The task was to read the word and decide whether the figure was a triangle...

  13. Decoding bipedal locomotion from the rat sensorimotor cortex

    Science.gov (United States)

    Rigosa, J.; Panarese, A.; Dominici, N.; Friedli, L.; van den Brand, R.; Carpaneto, J.; DiGiovanna, J.; Courtine, G.; Micera, S.

    2015-10-01

    Objective. Decoding forelimb movements from the firing activity of cortical neurons has been interfaced with robotic and prosthetic systems to replace lost upper limb functions in humans. Despite the potential of this approach to improve locomotion and facilitate gait rehabilitation, decoding lower limb movement from the motor cortex has received comparatively little attention. Here, we performed experiments to identify the type and amount of information that can be decoded from neuronal ensemble activity in the hindlimb area of the rat motor cortex during bipedal locomotor tasks. Approach. Rats were trained to stand, step on a treadmill, walk overground and climb staircases in a bipedal posture. To impose this gait, the rats were secured in a robotic interface that provided support against the direction of gravity and in the mediolateral direction, but behaved transparently in the forward direction. After completion of training, rats were chronically implanted with a micro-wire array spanning the left hindlimb motor cortex to record single and multi-unit activity, and bipolar electrodes into 10 muscles of the right hindlimb to monitor electromyographic signals. Whole-body kinematics, muscle activity, and neural signals were simultaneously recorded during execution of the trained tasks over multiple days of testing. Hindlimb kinematics, muscle activity, gait phases, and locomotor tasks were decoded using offline classification algorithms. Main results. We found that the stance and swing phases of gait and the locomotor tasks were detected with accuracies as robust as 90% in all rats. Decoded hindlimb kinematics and muscle activity exhibited a larger variability across rats and tasks. Significance. Our study shows that the rodent motor cortex contains useful information for lower limb neuroprosthetic development. However, brain-machine interfaces estimating gait phases or locomotor behaviors, instead of continuous variables such as limb joint positions or speeds

  14. Application of Beyond Bound Decoding for High Speed Optical Communications

    DEFF Research Database (Denmark)

    Li, Bomin; Larsen, Knud J.; Vegas Olmos, Juan José

    2013-01-01

    This paper studies the application of beyond bound decoding method for high speed optical communications. This hard-decision decoding method outperforms traditional minimum distance decoding method, with a total net coding gain of 10.36 dB....

  15. Encoding and Decoding Models in Cognitive Electrophysiology

    Directory of Open Access Journals (Sweden)

    Christopher R. Holdgraf

    2017-09-01

    Full Text Available Cognitive neuroscience has seen rapid growth in the size and complexity of data recorded from the human brain as well as in the computational tools available to analyze this data. This data explosion has resulted in an increased use of multivariate, model-based methods for asking neuroscience questions, allowing scientists to investigate multiple hypotheses with a single dataset, to use complex, time-varying stimuli, and to study the human brain under more naturalistic conditions. These tools come in the form of “Encoding” models, in which stimulus features are used to model brain activity, and “Decoding” models, in which neural features are used to generated a stimulus output. Here we review the current state of encoding and decoding models in cognitive electrophysiology and provide a practical guide toward conducting experiments and analyses in this emerging field. Our examples focus on using linear models in the study of human language and audition. We show how to calculate auditory receptive fields from natural sounds as well as how to decode neural recordings to predict speech. The paper aims to be a useful tutorial to these approaches, and a practical introduction to using machine learning and applied statistics to build models of neural activity. The data analytic approaches we discuss may also be applied to other sensory modalities, motor systems, and cognitive systems, and we cover some examples in these areas. In addition, a collection of Jupyter notebooks is publicly available as a complement to the material covered in this paper, providing code examples and tutorials for predictive modeling in python. The aim is to provide a practical understanding of predictive modeling of human brain data and to propose best-practices in conducting these analyses.

  16. Neural Response After a Single ECT Session During Retrieval of Emotional Self-Referent Words in Depression: A Randomized, Sham-Controlled fMRI Study

    Science.gov (United States)

    Miskowiak, Kamilla W; Macoveanu, Julian; Jørgensen, Martin B; Støttrup, Mette M; Ott, Caroline V; Jensen, Hans M; Jørgensen, Anders; Harmer, J; Paulson, Olaf B; Kessing, Lars V; Siebner, Hartwig R

    2018-01-01

    Abstract Background Negative neurocognitive bias is a core feature of depression that is reversed by antidepressant drug treatment. However, it is unclear whether modulation of neurocognitive bias is a common mechanism of distinct biological treatments. This randomized controlled functional magnetic resonance imaging study explored the effects of a single electroconvulsive therapy session on self-referent emotional processing. Methods Twenty-nine patients with treatment-resistant major depressive disorder were randomized to one active or sham electroconvulsive therapy session at the beginning of their electroconvulsive therapy course in a double-blind, between-groups design. The following day, patients were given a self-referential emotional word categorization test and a free recall test. This was followed by an incidental word recognition task during whole-brain functional magnetic resonance imaging at 3T. Mood was assessed at baseline, on the functional magnetic resonance imaging day, and after 6 electroconvulsive therapy sessions. Data were complete and analyzed for 25 patients (electroconvulsive therapy: n = 14, sham: n = 11). The functional magnetic resonance imaging data were analyzed using the FMRIB Software Library randomize algorithm, and the Threshold-Free Cluster Enhancement method was used to identify significant clusters (corrected at P words. However, electroconvulsive therapy reduced the retrieval-specific neural response for positive words in the left frontopolar cortex. This effect occurred in the absence of differences between groups in behavioral performance or mood symptoms. Conclusions The observed effect of electroconvulsive therapy on prefrontal response may reflect early facilitation of memory for positive self-referent information, which could contribute to improvements in depressive symptoms including feelings of self-worth with repeated treatments. PMID:29718333

  17. On minimizing the maximum broadcast decoding delay for instantly decodable network coding

    KAUST Repository

    Douik, Ahmed S.

    2014-09-01

    In this paper, we consider the problem of minimizing the maximum broadcast decoding delay experienced by all the receivers of generalized instantly decodable network coding (IDNC). Unlike the sum decoding delay, the maximum decoding delay as a definition of delay for IDNC allows a more equitable distribution of the delays between the different receivers and thus a better Quality of Service (QoS). In order to solve this problem, we first derive the expressions for the probability distributions of maximum decoding delay increments. Given these expressions, we formulate the problem as a maximum weight clique problem in the IDNC graph. Although this problem is known to be NP-hard, we design a greedy algorithm to perform effective packet selection. Through extensive simulations, we compare the sum decoding delay and the max decoding delay experienced when applying the policies to minimize the sum decoding delay and our policy to reduce the max decoding delay. Simulations results show that our policy gives a good agreement among all the delay aspects in all situations and outperforms the sum decoding delay policy to effectively minimize the sum decoding delay when the channel conditions become harsher. They also show that our definition of delay significantly improve the number of served receivers when they are subject to strict delay constraints.

  18. A class of Sudan-decodable codes

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Refslund

    2000-01-01

    In this article, Sudan's algorithm is modified into an efficient method to list-decode a class of codes which can be seen as a generalization of Reed-Solomon codes. The algorithm is specialized into a very efficient method for unique decoding. The code construction can be generalized based...

  19. Deep Space Network turbo decoder implementation

    Science.gov (United States)

    Berner, Jeff B.; Andrews, Kenneth S.; Bryant, Scott H.

    2001-01-01

    A new decoder is being developed by the Jet Propulsion Laboratory for NASA's Deep Space Network. This unit will decode the new turbo codes, which have recently been approved by the Consultative Committee for Space Data Systems (CCSDS). Turbo codes provide up to 0.8 dB improvement in Eb/No over the current best codes used by deep space missions.

  20. Quality of life for children with cochlear implants: perceived benefits and problems and the perception of single words and emotional sounds.

    Science.gov (United States)

    Schorr, Efrat A; Roth, Froma P; Fox, Nathan A

    2009-02-01

    This study examined children's self-reported quality of life with a cochlear implant as related to children's actual perceptions of speech and the emotional information conveyed by sound. Effects of age at amplification with hearing aids and fitting of cochlear implants on perceived quality of life were also investigated. A self-reported quality of life questionnaire and assessments of speech perception (single words) and emotion identification were administered to a sample of 37 children with cochlear implants who were congenitally deaf, who were 5-14 years of age, and who all used spoken language. The children reported significant improvement in quality of life because of their cochlear implants, and they also reported low levels of concern about typical problems associated with wearing an implant. The children's perceived quality of life did not significantly predict speech perception performance at the single word level. In contrast, increased quality of life predicted better performance on the emotion identification task. Age at first use of amplification predicted perceived quality of life. The findings regarding age reinforce the importance of early detection and intervention for children's positive quality of life with cochlear implants later in childhood.

  1. Word for word: Multiple lexical access in speech production

    NARCIS (Netherlands)

    Levelt, W.J.M.; Meyer, A.S.

    2000-01-01

    It is quite normal for us to produce one or two million word tokens every year. Speaking is a dear occupation and producing words is at the core of it. Still, producing even a single word is a highly complex affair. Recently, Levelt, Roelofs, and Meyer (1999) reviewed their theory of lexical access

  2. Local Mode Analysis: Decoding IR Spectra by Visualizing Molecular Details.

    Science.gov (United States)

    Massarczyk, M; Rudack, T; Schlitter, J; Kuhne, J; Kötting, C; Gerwert, K

    2017-04-20

    Integration of experimental and computational approaches to investigate chemical reactions in proteins has proven to be very successful. Experimentally, time-resolved FTIR difference-spectroscopy monitors chemical reactions at atomic detail. To decode detailed structural information encoded in IR spectra, QM/MM calculations are performed. Here, we present a novel method which we call local mode analysis (LMA) for calculating IR spectra and assigning spectral IR-bands on the basis of movements of nuclei and partial charges from just a single QM/MM trajectory. Through LMA the decoding of IR spectra no longer requires several simulations or optimizations. The novel approach correlates the motions of atoms of a single simulation with the corresponding IR bands and provides direct access to the structural information encoded in IR spectra. Either the contributions of a particular atom or atom group to the complete IR spectrum of the molecule are visualized, or an IR-band is selected to visualize the corresponding structural motions. Thus, LMA decodes the detailed information contained in IR spectra and provides an intuitive approach for structural biologists and biochemists. The unique feature of LMA is the bidirectional analysis connecting structural details to spectral features and vice versa spectral features to molecular motions.

  3. Word Recognition in Auditory Cortex

    Science.gov (United States)

    DeWitt, Iain D. J.

    2013-01-01

    Although spoken word recognition is more fundamental to human communication than text recognition, knowledge of word-processing in auditory cortex is comparatively impoverished. This dissertation synthesizes current models of auditory cortex, models of cortical pattern recognition, models of single-word reading, results in phonetics and results in…

  4. Hybrid EEG-fNIRS-Based Eight-Command Decoding for BCI: Application to Quadcopter Control.

    Science.gov (United States)

    Khan, Muhammad Jawad; Hong, Keum-Shik

    2017-01-01

    In this paper, a hybrid electroencephalography-functional near-infrared spectroscopy (EEG-fNIRS) scheme to decode eight active brain commands from the frontal brain region for brain-computer interface is presented. A total of eight commands are decoded by fNIRS, as positioned on the prefrontal cortex, and by EEG, around the frontal, parietal, and visual cortices. Mental arithmetic, mental counting, mental rotation, and word formation tasks are decoded with fNIRS, in which the selected features for classification and command generation are the peak, minimum, and mean ΔHbO values within a 2-s moving window. In the case of EEG, two eyeblinks, three eyeblinks, and eye movement in the up/down and left/right directions are used for four-command generation. The features in this case are the number of peaks and the mean of the EEG signal during 1 s window. We tested the generated commands on a quadcopter in an open space. An average accuracy of 75.6% was achieved with fNIRS for four-command decoding and 86% with EEG for another four-command decoding. The testing results show the possibility of controlling a quadcopter online and in real-time using eight commands from the prefrontal and frontal cortices via the proposed hybrid EEG-fNIRS interface.

  5. Hybrid EEG–fNIRS-Based Eight-Command Decoding for BCI: Application to Quadcopter Control

    Science.gov (United States)

    Khan, Muhammad Jawad; Hong, Keum-Shik

    2017-01-01

    In this paper, a hybrid electroencephalography–functional near-infrared spectroscopy (EEG–fNIRS) scheme to decode eight active brain commands from the frontal brain region for brain–computer interface is presented. A total of eight commands are decoded by fNIRS, as positioned on the prefrontal cortex, and by EEG, around the frontal, parietal, and visual cortices. Mental arithmetic, mental counting, mental rotation, and word formation tasks are decoded with fNIRS, in which the selected features for classification and command generation are the peak, minimum, and mean ΔHbO values within a 2-s moving window. In the case of EEG, two eyeblinks, three eyeblinks, and eye movement in the up/down and left/right directions are used for four-command generation. The features in this case are the number of peaks and the mean of the EEG signal during 1 s window. We tested the generated commands on a quadcopter in an open space. An average accuracy of 75.6% was achieved with fNIRS for four-command decoding and 86% with EEG for another four-command decoding. The testing results show the possibility of controlling a quadcopter online and in real-time using eight commands from the prefrontal and frontal cortices via the proposed hybrid EEG–fNIRS interface. PMID:28261084

  6. On the Eye Movement Control of Changing Reading Direction for a Single Word: The Case of Reading Numerals in Urdu.

    Science.gov (United States)

    Khan, Azizuddin; Loberg, Otto; Hautala, Jarkko

    2017-10-01

    Typically orthographies are consistent in terms of reading direction, i.e. from left-to-right or right-to-left. However, some are bidirectional, i.e., certain parts of the text, (such as numerals in Urdu), are read against the default reading direction. Such sudden changes in reading direction may challenge the reader in many ways, at the level of planning of saccadic eye movements, changing the direction of attention, word recognition processes and cognitive reading strategies. The present study attempts to understand how readers achieve such sudden changes in reading direction at the level of eye movements and conscious cognitive reading strategies. Urdu readers reported employing a two-stage strategy for reading numerals by first counting the number of digits during right-to-left fixations, and only then forming numeric representation during left-to-right fixations. Eye movement findings were aligned with this strategy usage, as long numerals were often read with deliberate forward-and-backward fixation sequences. In these sequences fixations preceding saccades to default reading direction were shorter than against it, suggesting that different cognitive processes such as counting and formation of numeric representation were involved in fixations preceding left- and right-directed saccades. Finally, the change against the default reading direction was preceded by highly inflated fixation duration, pinpointing the oculomotor, attentional and cognitive demands in executing sudden changes in reading direction.

  7. Heterogeneity of the left temporal lobe in semantic representation and control: priming multiple versus single meanings of ambiguous words.

    Science.gov (United States)

    Whitney, Carin; Jefferies, Elizabeth; Kircher, Tilo

    2011-04-01

    Semantic judgments involve both representations of meaning plus executive mechanisms that guide knowledge retrieval in a task-appropriate way. These 2 components of semantic cognition-representation and control-are commonly linked to left temporal and prefrontal cortex, respectively. This simple proposal, however, remains contentious because in most functional neuroimaging studies to date, the number of concepts being activated and the involvement of executive processes during retrieval are confounded. Using functional magnetic resonance imaging, we examined a task in which semantic representation and control demands were dissociable. Words with multiple meanings like "bank" served as targets in a double-prime paradigm, in which multiple meaning activation and maximal executive demands loaded onto different priming conditions. Anterior inferior temporal gyrus (ITG) was sensitive to the number of meanings that were retrieved, suggesting a role for this region in semantic representation, while posterior middle temporal gyrus (pMTG) and inferior frontal cortex showed greater activation in conditions that maximized executive demands. These results support a functional dissociation between left ITG and pMTG, consistent with a revised neural organization in which left prefrontal and posterior temporal areas work together to underpin aspects of semantic control.

  8. Comparing treatments for children with ADHD and word reading difficulties: A randomized clinical trial.

    Science.gov (United States)

    Tamm, Leanne; Denton, Carolyn A; Epstein, Jeffery N; Schatschneider, Christopher; Taylor, Heather; Arnold, L Eugene; Bukstein, Oscar; Anixt, Julia; Koshy, Anson; Newman, Nicholas C; Maltinsky, Jan; Brinson, Patricia; Loren, Richard E A; Prasad, Mary R; Ewing-Cobbs, Linda; Vaughn, Aaron

    2017-05-01

    This trial compared attention-deficit/hyperactivity disorder (ADHD) treatment alone, intensive reading intervention alone, and their combination for children with ADHD and word reading difficulties and disabilities (RD). Children (n = 216; predominantly African American males) in Grades 2-5 with ADHD and word reading/decoding deficits were randomized to ADHD treatment (medication + parent training), reading treatment (reading instruction), or combined ADHD + reading treatment. Outcomes were parent and teacher ADHD ratings and measures of word reading/decoding. Analyses utilized a mixed models covariate-adjusted gain score approach with posttest regressed onto pretest. Inattention and hyperactivity/impulsivity outcomes were significantly better in the ADHD (parent Hedges's g = .87/.75; teacher g = .67/.50) and combined (parent g = 1.06/.95; teacher g = .36/41) treatment groups than reading treatment alone; the ADHD and Combined groups did not differ significantly (parent g = .19/.20; teacher g = .31/.09). Word reading and decoding outcomes were significantly better in the reading (word reading g = .23; decoding g = .39) and combined (word reading g = .32; decoding g = .39) treatment groups than ADHD treatment alone; reading and combined groups did not differ (word reading g = .09; decoding g = .00). Significant group differences were maintained at the 3- to 5-month follow-up on all outcomes except word reading. Children with ADHD and RD benefit from specific treatment of each disorder. ADHD treatment is associated with more improvement in ADHD symptoms than RD treatment, and reading instruction is associated with better word reading and decoding outcomes than ADHD treatment. The additive value of combining treatments was not significant within disorder, but the combination allows treating both disorders simultaneously. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  9. Co-lateralized bilingual mechanisms for reading in single and dual language contexts: evidence from visual half-field processing of action words in proficient bilinguals

    Directory of Open Access Journals (Sweden)

    Marlena eKrefta

    2015-08-01

    Full Text Available When reading, proficient bilinguals seem to engage the same cognitive circuits regardless of the language in use. Yet, whether or not such ‘bilingual’ mechanisms would be lateralized in the same way in distinct – single or dual – language contexts is a question for debate. To fill this gap, we tested 18 highly proficient Polish (L1 – English (L2 childhood bilinguals whose task was to read aloud one of the two laterally presented action verbs, one stimulus per visual half field. While in the single-language blocks only L1 or L2 words were shown, in the subsequent mixed-language blocks words from both languages were concurrently displayed. All stimuli were presented for 217 ms followed by masks in which letters were replaced with hash marks. Since in non-simultaneous bilinguals the control of language, skilled actions (including reading, and representations of action concepts are typically left lateralized, the vast majority of our participants showed the expected, significant right visual field advantage for L1 and L2, both for accuracy and response times. The observed effects were nevertheless associated with substantial variability in the strength of the lateralization of the mechanisms involved. Moreover, although it could be predicted that participants’ performance should be better in a single-language context, accuracy was significantly higher and response times were significantly shorter in a dual-language context, irrespective of the language tested. Finally, for both accuracy and response times, there were significant positive correlations between the laterality indices (LIs of both languages independent of the context, with a significantly greater left-sided advantage for L1 vs. L2 in the mixed-language blocks, based on LIs calculated for response times. Thus, despite similar representations of the two languages in the bilingual brain, these results also point to the functional separation of L1 and L2 in the dual

  10. Words Do Come Easy (Sometimes)

    DEFF Research Database (Denmark)

    Starrfelt, Randi; Petersen, Anders; Vangkilde, Signe Allerup

    Words are made of letters, and yet sometimes it is easier to identify a word than a single letter. This word superiority effect (WSE) is observed when singly presented written stimuli are presented very briefly or degraded by visual noise. It is unclear at which level in visual perception...... multiple stimuli are presented simultaneously: Are words treated as units or wholes in visual short term memory? Using methods based on a Theory of Visual Attention (TVA), we measured perceptual threshold, visual processing speed and visual short term memory capacity for words and letters, in two simple...... a different pattern: Letters are perceived more easily than words, and this is reflected both in perceptual processing speed and short term memory capacity. So even if single words do come easy, they seem to enjoy no advantage in visual short term memory....

  11. Optical RAM row access using WDM-enabled all-passive row/column decoders

    Science.gov (United States)

    Papaioannou, Sotirios; Alexoudi, Theoni; Kanellos, George T.; Miliou, Amalia; Pleros, Nikos

    2014-03-01

    Towards achieving a functional RAM organization that reaps the advantages offered by optical technology, a complete set of optical peripheral modules, namely the Row (RD) and Column Decoder (CD) units, is required. In this perspective, we demonstrate an all-passive 2×4 optical RAM RD with row access operation and subsequent all-passive column decoding to control the access of WDM-formatted words in optical RAM rows. The 2×4 RD exploits a WDM-formatted 2-bit-long memory WordLine address along with its complementary value, all of them encoded on four different wavelengths and broadcasted to all RAM rows. The RD relies on an all-passive wavelength-selective filtering matrix (λ-matrix) that ensures a logical `0' output only at the selected RAM row. Subsequently, the RD output of each row drives the respective SOA-MZI-based Row Access Gate (AG) to grant/block the entry of the incoming data words to the whole memory row. In case of a selected row, the data word exits the row AG and enters the respective CD that relies on an allpassive wavelength-selective Arrayed Waveguide Grating (AWG) for decoding the word bits into their individual columns. Both RD and CD procedures are carried out without requiring any active devices, assuming that the memory address and data word bits as well as their inverted values will be available in their optical form by the CPU interface. Proof-of-concept experimental verification exploiting cascaded pairs of AWGs as the λ-matrix is demonstrated at 10Gb/s, providing error-free operation with a peak power penalty lower than 0.2dB for all optical word channels.

  12. Three phase full wave dc motor decoder

    Science.gov (United States)

    Studer, P. A. (Inventor)

    1977-01-01

    A three phase decoder for dc motors is disclosed which employs an extremely simple six transistor circuit to derive six properly phased output signals for fullwave operation of dc motors. Six decoding transistors are coupled at their base-emitter junctions across a resistor network arranged in a delta configuration. Each point of the delta configuration is coupled to one of three position sensors which sense the rotational position of the motor. A second embodiment of the invention is disclosed in which photo-optical isolators are used in place of the decoding transistors.

  13. Decoding Algorithms for Random Linear Network Codes

    DEFF Research Database (Denmark)

    Heide, Janus; Pedersen, Morten Videbæk; Fitzek, Frank

    2011-01-01

    We consider the problem of efficient decoding of a random linear code over a finite field. In particular we are interested in the case where the code is random, relatively sparse, and use the binary finite field as an example. The goal is to decode the data using fewer operations to potentially...... achieve a high coding throughput, and reduce energy consumption.We use an on-the-fly version of the Gauss-Jordan algorithm as a baseline, and provide several simple improvements to reduce the number of operations needed to perform decoding. Our tests show that the improvements can reduce the number...

  14. Discrete versus multiple word displays: A re-analysis of studies comparing dyslexic and typically developing children

    Directory of Open Access Journals (Sweden)

    Pierluigi eZoccolotti

    2015-10-01

    Full Text Available The study examines whether impairments in reading a text can be explained by a deficit in word decoding or an additional deficit in the processes governing the integration of reading subcomponents (including eye movement programming and pronunciation should also be postulated. We report a re-analysis of data from eleven previous experiments conducted in our lab where the reading performance on single, discrete word displays as well multiple displays (texts, and in few cases also word lists was investigated in groups of dyslexic children and typically developing readers. The analysis focuses on measures of time and not accuracy.Across experiments, dyslexic children are slower and more variable than typically developing readers in reading texts as well as vocal RTs to singly presented words; the dis-homogeneity in variability between groups points to the inappropriateness of standard measures of size effect (such as Cohen’s d, and suggests the use of the ratio between groups’ performance. The mean ratio for text reading is 1.95 across experiments. Mean ratio for vocal RTs for singly presented words is considerably smaller (1.52. Furthermore, this latter value is probably an overestimation as considering total reading times (i.e., a measure including also the pronunciation component considerably reduces the group difference in vocal RTs (1.19 according to Martelli et al., 2014. The ratio difference between single and multiple displays does not depend upon the presence of a semantic context in the case of texts as large ratios are also observed with lists of unrelated words (though studies testing this aspect were few.We conclude that, if care is taken in using appropriate comparisons, the deficit in reading texts or lists of words is appreciably greater than that revealed with discrete word presentations. Thus, reading multiple stimuli present a specific, additional challenge to dyslexic children indicating that models of reading should

  15. Efficient decoding with steady-state Kalman filter in neural interface systems.

    Science.gov (United States)

    Malik, Wasim Q; Truccolo, Wilson; Brown, Emery N; Hochberg, Leigh R

    2011-02-01

    The Kalman filter is commonly used in neural interface systems to decode neural activity and estimate the desired movement kinematics. We analyze a low-complexity Kalman filter implementation in which the filter gain is approximated by its steady-state form, computed offline before real-time decoding commences. We evaluate its performance using human motor cortical spike train data obtained from an intracortical recording array as part of an ongoing pilot clinical trial. We demonstrate that the standard Kalman filter gain converges to within 95% of the steady-state filter gain in 1.5±0.5 s (mean ±s.d.). The difference in the intended movement velocity decoded by the two filters vanishes within 5 s, with a correlation coefficient of 0.99 between the two decoded velocities over the session length. We also find that the steady-state Kalman filter reduces the computational load (algorithm execution time) for decoding the firing rates of 25±3 single units by a factor of 7.0±0.9. We expect that the gain in computational efficiency will be much higher in systems with larger neural ensembles. The steady-state filter can thus provide substantial runtime efficiency at little cost in terms of estimation accuracy. This far more efficient neural decoding approach will facilitate the practical implementation of future large-dimensional, multisignal neural interface systems.

  16. Decoding small surface codes with feedforward neural networks

    Science.gov (United States)

    Varsamopoulos, Savvas; Criger, Ben; Bertels, Koen

    2018-01-01

    Surface codes reach high error thresholds when decoded with known algorithms, but the decoding time will likely exceed the available time budget, especially for near-term implementations. To decrease the decoding time, we reduce the decoding problem to a classification problem that a feedforward neural network can solve. We investigate quantum error correction and fault tolerance at small code distances using neural network-based decoders, demonstrating that the neural network can generalize to inputs that were not provided during training and that they can reach similar or better decoding performance compared to previous algorithms. We conclude by discussing the time required by a feedforward neural network decoder in hardware.

  17. Hierarchical multi-resolution mesh networks for brain decoding.

    Science.gov (United States)

    Onal Ertugrul, Itir; Ozay, Mete; Yarman Vural, Fatos T

    2017-10-04

    Human brain is supposed to process information in multiple frequency bands. Therefore, we can extract diverse information from functional Magnetic Resonance Imaging (fMRI) data by processing it at multiple resolutions. We propose a framework, called Hierarchical Multi-resolution Mesh Networks (HMMNs), which establishes a set of brain networks at multiple resolutions of fMRI signal to represent the underlying cognitive process. Our framework, first, decomposes the fMRI signal into various frequency subbands using wavelet transform. Then, a brain network is formed at each subband by ensembling a set of local meshes. Arc weights of each local mesh are estimated by ridge regression. Finally, adjacency matrices of mesh networks obtained at different subbands are used to train classifiers in an ensemble learning architecture, called fuzzy stacked generalization (FSG). Our decoding performances on Human Connectome Project task-fMRI dataset reflect that HMMNs can successfully discriminate tasks with 99% accuracy, across 808 subjects. Diversity of information embedded in mesh networks of multiple subbands enables the ensemble of classifiers to collaborate with each other for brain decoding. The suggested HMMNs decode the cognitive tasks better than a single classifier applied to any subband. Also mesh networks have a better representation power compared to pairwise correlations or average voxel time series. Moreover, fusion of diverse information using FSG outperforms fusion with majority voting. We conclude that, fMRI data, recorded during a cognitive task, provide diverse information in multi-resolution mesh networks. Our framework fuses this complementary information and boosts the brain decoding performances obtained at individual subbands.

  18. Low-Power Bitstream-Residual Decoder for H.264/AVC Baseline Profile Decoding

    Directory of Open Access Journals (Sweden)

    Xu Ke

    2009-01-01

    Full Text Available Abstract We present the design and VLSI implementation of a novel low-power bitstream-residual decoder for H.264/AVC baseline profile. It comprises a syntax parser, a parameter decoder, and an Inverse Quantization Inverse Transform (IQIT decoder. The syntax parser detects and decodes each incoming codeword in the bitstream under the control of a hierarchical Finite State Machine (FSM; the IQIT decoder performs inverse transform and quantization with pipelining and parallelism. Various power reduction techniques, such as data-driven based on statistic results, nonuniform partition, precomputation, guarded evaluation, hierarchical FSM decomposition, TAG method, zero-block skipping, and clock gating , are adopted and integrated throughout the bitstream-residual decoder. With innovative architecture, the proposed design is able to decode QCIF video sequences of 30 fps at a clock rate as low as 1.5 MHz. A prototype H.264/AVC baseline decoding chip utilizing the proposed decoder is fabricated in UMC 0.18  m 1P6M CMOS technology. The proposed design is measured under 1 V 1.8 V supply with 0.1 V step. It dissipates 76  W at 1 V and 253  W at 1.8 V.

  19. Predicting word decoding and word spelling development in children with Specific Language Impairment

    NARCIS (Netherlands)

    Weerdenburg, M.W.C. van; Verhoeven, L.T.W.; Bosman, A.M.T.; Balkom, L.J.M. van

    2011-01-01

    This longitudinal investigation on Dutch children with Specific Language Impairment (SLI) aimed at determining the predictive value of statistically uncorrelated language proficiencies on later reading and spelling skills in Dutch. Language abilities, tested with an extensive test battery at the

  20. Don't words come easy? A psychophysical exploration of word superiority

    DEFF Research Database (Denmark)

    Starrfelt, Randi; Petersen, Anders; Vangkilde, Signe Allerup

    2013-01-01

    Words are made of letters, and yet sometimes it is easier to identify a word than a single letter. This word superiority effect (WSE) has been observed when written stimuli are presented very briefly or degraded by visual noise. We compare performance with letters and words in three experiments, ...... and visual short term memory capacity. So, even if single words come easy, there is a limit to the word superiority effect....

  1. Decoding the Disciplines as a Hermeneutic Practice

    Science.gov (United States)

    Yeo, Michelle

    2017-01-01

    This chapter argues that expert practice is an inquiry that surfaces a hermeneutic relationship between theory, practice, and the world, with implications for new lines of questioning in the Decoding interview.

  2. Nine Words - Nine Columns

    DEFF Research Database (Denmark)

    Trempe Jr., Robert B.; Buthke, Jan

    2016-01-01

    of computational and mechanical processes towards an anesthetic. Each team received a single word, translating and evolving that word first into a double-curved computational surface, next a ruled computational surface, and then a physically shaped foam mold via a 6-axis robot. The foam molds then operated...... as formwork for the shaping of wood veneer. The resulting columns ‘wear’ every aspect of this design pipeline process and display the power of process towards an architectural resolution....

  3. Fast mental states decoding in mixed reality.

    Directory of Open Access Journals (Sweden)

    Daniele eDe Massari

    2014-11-01

    Full Text Available The combination of Brain-Computer Interface technology, allowing online monitoring and decoding of brain activity, with virtual and mixed reality systems may help to shape and guide implicit and explicit learning using ecological scenarios. Real-time information of ongoing brain states acquired through BCI might be exploited for controlling data presentation in virtual environments. In this context, assessing to what extent brain states can be discriminated during mixed reality experience is critical for adapting specific data features to contingent brain activity. In this study we recorded EEG data while participants experienced a mixed reality scenario implemented through the eXperience Induction Machine (XIM. The XIM is a novel framework modeling the integration of a sensing system that evaluates and measures physiological and psychological states with a number of actuators and effectors that coherently reacts to the user's actions. We then assessed continuous EEG-based discrimination of spatial navigation, reading and calculation performed in mixed reality, using LDA and SVM classifiers. Dynamic single trial classification showed high accuracy of LDA and SVM classifiers in detecting multiple brain states as well as in differentiating between high and low mental workload, using a 5 s time-window shifting every 200 ms. Our results indicate overall better performance of LDA with respect to SVM and suggest applicability of our approach in a BCI-controlled mixed reality scenario. Ultimately, successful prediction of brain states might be used to drive adaptation of data representation in order to boost information processing in mixed reality.

  4. Mapping of MPEG-4 decoding on a flexible architecture platform

    Science.gov (United States)

    van der Tol, Erik B.; Jaspers, Egbert G.

    2001-12-01

    In the field of consumer electronics, the advent of new features such as Internet, games, video conferencing, and mobile communication has triggered the convergence of television and computers technologies. This requires a generic media-processing platform that enables simultaneous execution of very diverse tasks such as high-throughput stream-oriented data processing and highly data-dependent irregular processing with complex control flows. As a representative application, this paper presents the mapping of a Main Visual profile MPEG-4 for High-Definition (HD) video onto a flexible architecture platform. A stepwise approach is taken, going from the decoder application toward an implementation proposal. First, the application is decomposed into separate tasks with self-contained functionality, clear interfaces, and distinct characteristics. Next, a hardware-software partitioning is derived by analyzing the characteristics of each task such as the amount of inherent parallelism, the throughput requirements, the complexity of control processing, and the reuse potential over different applications and different systems. Finally, a feasible implementation is proposed that includes amongst others a very-long-instruction-word (VLIW) media processor, one or more RISC processors, and some dedicated processors. The mapping study of the MPEG-4 decoder proves the flexibility and extensibility of the media-processing platform. This platform enables an effective HW/SW co-design yielding a high performance density.

  5. Real-time inference of word relevance from electroencephalogram and eye gaze

    Science.gov (United States)

    Wenzel, M. A.; Bogojeski, M.; Blankertz, B.

    2017-10-01

    Objective. Brain-computer interfaces can potentially map the subjective relevance of the visual surroundings, based on neural activity and eye movements, in order to infer the interest of a person in real-time. Approach. Readers looked for words belonging to one out of five semantic categories, while a stream of words passed at different locations on the screen. It was estimated in real-time which words and thus which semantic category interested each reader based on the electroencephalogram (EEG) and the eye gaze. Main results. Words that were subjectively relevant could be decoded online from the signals. The estimation resulted in an average rank of 1.62 for the category of interest among the five categories after a hundred words had been read. Significance. It was demonstrated that the interest of a reader can be inferred online from EEG and eye tracking signals, which can potentially be used in novel types of adaptive software, which enrich the interaction by adding implicit information about the interest of the user to the explicit interaction. The study is characterised by the following novelties. Interpretation with respect to the word meaning was necessary in contrast to the usual practice in brain-computer interfacing where stimulus recognition is sufficient. The typical counting task was avoided because it would not be sensible for implicit relevance detection. Several words were displayed at the same time, in contrast to the typical sequences of single stimuli. Neural activity was related with eye tracking to the words, which were scanned without restrictions on the eye movements.

  6. Word classes

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    2007-01-01

    This article provides an overview of recent literature and research on word classes, focusing in particular on typological approaches to word classification. The cross-linguistic classification of word class systems (or parts-of-speech systems) presented in this article is based on statements found...... in grammatical descriptions of some 50 languages, which together constitute a representative sample of the world’s languages (Hengeveld et al. 2004: 529). It appears that there are both quantitative and qualitative differences between word class systems of individual languages. Whereas some languages employ...... a parts-of-speech system that includes the categories Verb, Noun, Adjective and Adverb, other languages may use only a subset of these four lexical categories. Furthermore, quite a few languages have a major word class whose members cannot be classified in terms of the categories Verb – Noun – Adjective...

  7. The effect of vocabulary knowledge on novel word identification.

    Science.gov (United States)

    Mitchell, Alison M; Brady, Susan A

    2013-10-01

    The study investigated the relationship between vocabulary knowledge and novel word reading. Fourth-grade students were assessed on standardized measures of word identification, decoding, and receptive vocabulary, as well as on an experimental word identification measure using words that students in the fourth grade are unlikely to have seen before in print. In the experimental measure, pairs of words were matched on printed frequency and orthographic pattern (with a variety of spelling patterns represented), but differed in terms of the frequency of expected oral exposure for children (i.e., higher vs. lower). Results showed that students' receptive vocabulary knowledge was significantly related to performance on both the standardized and experimental measures of word identification, even after accounting for the substantial amount of variance explained by decoding ability. Students performed better reading the words with higher expected oral frequencies on the experimental task than on those items with lower expected oral frequencies. The results point to the benefits, albeit modest, of oral word familiarity for reading words when they are first encountered in print and suggest that this top-down effect is not limited to exception words, as has been suggested, but has a wider scope.

  8. From word superiority to word inferiority: Visual processing of letters and words in pure alexia

    DEFF Research Database (Denmark)

    Habekost, Thomas; Petersen, Anders; Behrmann, Marlene

    2014-01-01

    impaired in letter naming and word processing, and performance with letters and words was dissociated in all four patients, with word reading being more severely impaired than letter recognition. This suggests that the word reading deficit in pure alexia may not be reduced to an impairment in single letter......Visual processing and naming of individual letters and short words were investigated in four patients with pure alexia. To test processing at different levels, the same stimuli were studied across a naming task and a visual perception task. The normal word superiority effect was eliminated in both...... tasks for all patients, and this pattern was more pronounced in the more severely affected patients. The relationship between performance with single letters and words was, however, not straightforward: One patient performed within the normal range on the letter perception task, while being severely...

  9. Decoding spatial attention with EEG and virtual acoustic space.

    Science.gov (United States)

    Dong, Yue; Raif, Kaan E; Determan, Sarah C; Gai, Yan

    2017-11-01

    Decoding spatial attention based on brain signals has wide applications in brain-computer interface (BCI). Previous BCI systems mostly relied on visual patterns or auditory stimulation (e.g., loudspeakers) to evoke synchronous brain signals. There would be difficulties to cover a large range of spatial locations with such a stimulation protocol. The present study explored the possibility of using virtual acoustic space and a visual-auditory matching paradigm to overcome this issue. The technique has the flexibility of generating sound stimulation from virtually any spatial location. Brain signals of eight human subjects were obtained with a 32-channel Electroencephalogram (EEG). Two amplitude-modulated noise or speech sentences carrying distinct spatial information were presented concurrently. Each sound source was tagged with a unique modulation phase so that the phase of the recorded EEG signals indicated the sound being attended to. The phase-tagged sound was further filtered with head-related transfer functions to create the sense of virtual space. Subjects were required to pay attention to the sound source that best matched the location of a visual target. For all the subjects, the phase of a single sound could be accurately reflected over the majority of electrodes based on EEG responses of 90 s or less. The electrodes providing significant decoding performance on auditory attention were fewer and may require longer EEG responses. The reliability and efficiency of decoding with a single electrode varied with subjects. Overall, the virtual acoustic space protocol has the potential of being used in practical BCI systems. © 2017 Saint Louis University. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  10. Modified Decoding Algorithm of LLR-SPA

    Directory of Open Access Journals (Sweden)

    Zhongxun Wang

    2014-09-01

    Full Text Available In wireless sensor networks, the energy consumption is mainly occurred in the stage of information transmission. The Low Density Parity Check code can make full use of the channel information to save energy. Because of the widely used decoding algorithm of the Low Density Parity Check code, this paper proposes a new decoding algorithm which is based on the LLR-SPA (Sum-Product Algorithm in Log-Likelihood-domain to improve the accuracy of the decoding algorithm. In the modified algorithm, a piecewise linear function is used to approximate the complicated Jacobi correction term in LLR-SPA decoding algorithm. Construct the tangent by the tangency point to the function of Jacobi correction term, which is based on the first order Taylor Series. In this way, the proposed piecewise linear approximation offers almost a perfect match to the function of Jacobi correction term. Meanwhile, the proposed piecewise linear approximation could avoid the operation of logarithmic which is more suitable for practical application. The simulation results show that the proposed algorithm could improve the decoding accuracy greatly without noticeable variation of the computational complexity.

  11. Symbol synchronization for the TDRSS decoder

    Science.gov (United States)

    Costello, D. J., Jr.

    1983-01-01

    Each 8 bits out of the Viterbi decoder correspond to one symbol of the R/S code. Synchronization must be maintained here so that each 8-bit symbol delivered to the R/S decoder corresponds to an 8-bit symbol from the R/S encoder. Lack of synchronization, would cause an error in almost every R/S symbol since even a - 1-bit sync slip shifts every bit in each 8-bit symbol by one position, therby confusing the mapping betweeen 8-bit sequences and symbols. The error correcting capability of the R/S code would be exceeded. Possible ways to correcting this condition include: (1) designing the R/S decoder to recognize the overload and shifting the output sequence of the inner decoder to establish a different sync state; (2) using the characteristics of the inner decoder to establish symbol synchronization for the outer code, with or without a deinterleaver and an interleaver; and (3) modifying the encoder to alternate periodically between two sets of generators.

  12. Brain-state classification and a dual-state decoder dramatically improve the control of cursor movement through a brain-machine interface

    Science.gov (United States)

    Sachs, Nicholas A.; Ruiz-Torres, Ricardo; Perreault, Eric J.; Miller, Lee E.

    2016-02-01

    Objective. It is quite remarkable that brain machine interfaces (BMIs) can be used to control complex movements with fewer than 100 neurons. Success may be due in part to the limited range of dynamical conditions under which most BMIs are tested. Achieving high-quality control that spans these conditions with a single linear mapping will be more challenging. Even for simple reaching movements, existing BMIs must reduce the stochastic noise of neurons by averaging the control signals over time, instead of over the many neurons that normally control movement. This forces a compromise between a decoder with dynamics allowing rapid movement and one that allows postures to be maintained with little jitter. Our current work presents a method for addressing this compromise, which may also generalize to more highly varied dynamical situations, including movements with more greatly varying speed. Approach. We have developed a system that uses two independent Wiener filters as individual components in a single decoder, one optimized for movement, and the other for postural control. We computed an LDA classifier using the same neural inputs. The decoder combined the outputs of the two filters in proportion to the likelihood assigned by the classifier to each state. Main results. We have performed online experiments with two monkeys using this neural-classifier, dual-state decoder, comparing it to a standard, single-state decoder as well as to a dual-state decoder that switched states automatically based on the cursor’s proximity to a target. The performance of both monkeys using the classifier decoder was markedly better than that of the single-state decoder and comparable to the proximity decoder. Significance. We have demonstrated a novel strategy for dealing with the need to make rapid movements while also maintaining precise cursor control when approaching and stabilizing within targets. Further gains can undoubtedly be realized by optimizing the performance of the

  13. Completion time reduction in instantly decodable network coding through decoding delay control

    KAUST Repository

    Douik, Ahmed S.

    2014-12-01

    For several years, the completion time and the decoding delay problems in Instantly Decodable Network Coding (IDNC) were considered separately and were thought to completely act against each other. Recently, some works aimed to balance the effects of these two important IDNC metrics but none of them studied a further optimization of one by controlling the other. In this paper, we study the effect of controlling the decoding delay to reduce the completion time below its currently best known solution. We first derive the decoding-delay-dependent expressions of the users\\' and their overall completion times. Although using such expressions to find the optimal overall completion time is NP-hard, we use a heuristic that minimizes the probability of increasing the maximum of these decoding-delay-dependent completion time expressions after each transmission through a layered control of their decoding delays. Simulation results show that this new algorithm achieves both a lower mean completion time and mean decoding delay compared to the best known heuristic for completion time reduction. The gap in performance becomes significant for harsh erasure scenarios.

  14. Neural Encoding and Decoding with Deep Learning for Dynamic Natural Vision.

    Science.gov (United States)

    Wen, Haiguang; Shi, Junxing; Zhang, Yizhen; Lu, Kun-Han; Cao, Jiayue; Liu, Zhongming

    2017-10-20

    Convolutional neural network (CNN) driven by image recognition has been shown to be able to explain cortical responses to static pictures at ventral-stream areas. Here, we further showed that such CNN could reliably predict and decode functional magnetic resonance imaging data from humans watching natural movies, despite its lack of any mechanism to account for temporal dynamics or feedback processing. Using separate data, encoding and decoding models were developed and evaluated for describing the bi-directional relationships between the CNN and the brain. Through the encoding models, the CNN-predicted areas covered not only the ventral stream, but also the dorsal stream, albeit to a lesser degree; single-voxel response was visualized as the specific pixel pattern that drove the response, revealing the distinct representation of individual cortical location; cortical activation was synthesized from natural images with high-throughput to map category representation, contrast, and selectivity. Through the decoding models, fMRI signals were directly decoded to estimate the feature representations in both visual and semantic spaces, for direct visual reconstruction and semantic categorization, respectively. These results corroborate, generalize, and extend previous findings, and highlight the value of using deep learning, as an all-in-one model of the visual cortex, to understand and decode natural vision. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  15. Neuroprosthetic Decoder Training as Imitation Learning.

    Directory of Open Access Journals (Sweden)

    Josh Merel

    2016-05-01

    Full Text Available Neuroprosthetic brain-computer interfaces function via an algorithm which decodes neural activity of the user into movements of an end effector, such as a cursor or robotic arm. In practice, the decoder is often learned by updating its parameters while the user performs a task. When the user's intention is not directly observable, recent methods have demonstrated value in training the decoder against a surrogate for the user's intended movement. Here we show that training a decoder in this way is a novel variant of an imitation learning problem, where an oracle or expert is employed for supervised training in lieu of direct observations, which are not available. Specifically, we describe how a generic imitation learning meta-algorithm, dataset aggregation (DAgger, can be adapted to train a generic brain-computer interface. By deriving existing learning algorithms for brain-computer interfaces in this framework, we provide a novel analysis of regret (an important metric of learning efficacy for brain-computer interfaces. This analysis allows us to characterize the space of algorithmic variants and bounds on their regret rates. Existing approaches for decoder learning have been performed in the cursor control setting, but the available design principles for these decoders are such that it has been impossible to scale them to naturalistic settings. Leveraging our findings, we then offer an algorithm that combines imitation learning with optimal control, which should allow for training of arbitrary effectors for which optimal control can generate goal-oriented control. We demonstrate this novel and general BCI algorithm with simulated neuroprosthetic control of a 26 degree-of-freedom model of an arm, a sophisticated and realistic end effector.

  16. A forward error correction technique using a high-speed, high-rate single chip codec

    Science.gov (United States)

    Boyd, R. W.; Hartman, W. F.; Jones, Robert E.

    1989-01-01

    The authors describe an error-correction coding approach that allows operation in either burst or continuous modes at data rates of multiple hundreds of megabits per second. Bandspreading is low since the code rate is 7/8 or greater, which is consistent with high-rate link operation. The encoder, along with a hard-decision decoder, fits on a single application-specific integrated circuit (ASIC) chip. Soft-decision decoding is possible utilizing applique hardware in conjunction with the hard-decision decoder. Expected coding gain is a function of the application and is approximately 2.5 dB for hard-decision decoding at 10-5 bit-error rate with phase-shift-keying modulation and additive Gaussian white noise interference. The principal use envisioned for this technique is to achieve a modest amount of coding gain on high-data-rate, bandwidth-constrained channels. Data rates of up to 300 Mb/s can be accommodated by the codec chip. The major objective is burst-mode communications, where code words are composed of 32 n data bits followed by 32 overhead bits.

  17. Periodic words connected with the Fibonacci words

    Directory of Open Access Journals (Sweden)

    G. M. Barabash

    2016-06-01

    Full Text Available In this paper we introduce two families of periodic words (FLP-words of type 1 and FLP-words of type 2 that are connected with the Fibonacci words and investigated their properties.

  18. Decoding Hermitian Codes with Sudan's Algorithm

    DEFF Research Database (Denmark)

    Høholdt, Tom; Nielsen, Rasmus Refslund

    1999-01-01

    We present an efficient implementation of Sudan's algorithm for list decoding Hermitian codes beyond half the minimum distance. The main ingredients are an explicit method to calculate so-called increasing zero bases, an efficient interpolation algorithm for finding the Q-polynomial, and a reduct......We present an efficient implementation of Sudan's algorithm for list decoding Hermitian codes beyond half the minimum distance. The main ingredients are an explicit method to calculate so-called increasing zero bases, an efficient interpolation algorithm for finding the Q...

  19. High Speed Frame Synchronization and Viterbi Decoding

    DEFF Research Database (Denmark)

    Paaske, Erik; Justesen, Jørn; Larsen, Knud J.

    1996-01-01

    The purpose of Phase 1 of the study is to describe the system structure and algorithms in sufficient detail to allow drawing the high level architecture of units containing frame synchronization and Viterbi decoding. The systems we consider are high data rate space communication systems. Also, th...... implementation uses a number of commercially available decoders while the the two others are completely new implementations aimed at ASICs, one for a data date of 75 Mbit/s and the second for a data rate of 150 Mbits/s....

  20. Decoding covert shifts of attention induced by ambiguous visuospatial cues

    Directory of Open Access Journals (Sweden)

    Romain eTrachel

    2015-06-01

    Full Text Available Simple and unambiguous visual cues (e.g. an arrow can be used to trigger covert shifts of visual attention away from the center of gaze. The processing of visual stimuli is enhanced at the attended location. Covert shifts of attention modulate the power of cerebral oscillations in the alpha band over parietal and occipital regions. These modulations are sufficiently robust to be decoded on a single trial basis from electro-encephalography (EEG signals. It is often assumed that covert attention shifts are under voluntary control, and also occur in more natural and complex environments, but there is no direct evidence to support this assumption. We address this important issue by using random-dot stimuli to cue one of two opposite locations, where a visual target is presented. We contrast two conditions in which the random-dot motion is either predictive of the target location or contains ambiguous information. Behavioral results show attention shifts in anticipation of the visual target, in both conditions. In addition, these attention shifts involve similar neural sources, and the EEG can be decoded on a single trial basis. These results shed a new light on the behavioral and neural correlates of visuospatial attention, with implications for Brain-Computer Interfaces (BCI based on covert attention shifts.

  1. Generalized Sudan's List Decoding for Order Domain Codes

    DEFF Research Database (Denmark)

    Geil, Hans Olav; Matsumoto, Ryutaroh

    2007-01-01

    We generalize Sudan's list decoding algorithm without multiplicity to evaluation codes coming from arbitrary order domains. The number of correctable errors by the proposed method is larger than the original list decoding without multiplicity.......We generalize Sudan's list decoding algorithm without multiplicity to evaluation codes coming from arbitrary order domains. The number of correctable errors by the proposed method is larger than the original list decoding without multiplicity....

  2. Tail Biting Trellis Representation of Codes: Decoding and Construction

    Science.gov (United States)

    Shao. Rose Y.; Lin, Shu; Fossorier, Marc

    1999-01-01

    This paper presents two new iterative algorithms for decoding linear codes based on their tail biting trellises, one is unidirectional and the other is bidirectional. Both algorithms are computationally efficient and achieves virtually optimum error performance with a small number of decoding iterations. They outperform all the previous suboptimal decoding algorithms. The bidirectional algorithm also reduces decoding delay. Also presented in the paper is a method for constructing tail biting trellises for linear block codes.

  3. Decoding of concatenated codes with interleaved outer codes

    DEFF Research Database (Denmark)

    Justesen, Jørn; Thommesen, Christian; Høholdt, Tom

    2004-01-01

    Recently Bleichenbacher et al. proposed a decoding algorithm for interleaved Reed/Solomon codes, which allows close to errors to be corrected in many cases. We discuss the application of this decoding algorithm to concatenated codes. (NK) N-K......Recently Bleichenbacher et al. proposed a decoding algorithm for interleaved Reed/Solomon codes, which allows close to errors to be corrected in many cases. We discuss the application of this decoding algorithm to concatenated codes. (NK) N-K...

  4. Decoding of concatenated codes with interleaved outer codes

    DEFF Research Database (Denmark)

    Justesen, Jørn; Høholdt, Tom; Thommesen, Christian

    2004-01-01

    Recently Bleichenbacher et al. proposed a decoding algorithm for interleaved (N, K) Reed-Solomon codes, which allows close to N-K errors to be corrected in many cases. We discuss the application of this decoding algorithm to concatenated codes.......Recently Bleichenbacher et al. proposed a decoding algorithm for interleaved (N, K) Reed-Solomon codes, which allows close to N-K errors to be corrected in many cases. We discuss the application of this decoding algorithm to concatenated codes....

  5. Learning words

    DEFF Research Database (Denmark)

    Jaswal, Vikram K.; Hansen, Mikkel

    2006-01-01

    Children tend to infer that when a speaker uses a new label, the label refers to an unlabeled object rather than one they already know the label for. Does this inference reflect a default assumption that words are mutually exclusive? Or does it instead reflect the result of a pragmatic reasoning...... process about what the speaker intended? In two studies, we distinguish between these possibilities. Preschoolers watched as a speaker pointed toward (Study 1) or looked at (Study 2) a familiar object while requesting the referent for a new word (e.g. 'Can you give me the blicket?'). In both studies......, despite the speaker's unambiguous behavioral cue indicating an intent to refer to a familiar object, children inferred that the novel label referred to an unfamiliar object. These results suggest that children expect words to be mutually exclusive even when a speaker provides some kinds of pragmatic...

  6. Word prediction

    Energy Technology Data Exchange (ETDEWEB)

    Rumelhart, D.E.; Skokowski, P.G.; Martin, B.O.

    1995-05-01

    In this project we have developed a language model based on Artificial Neural Networks (ANNs) for use in conjunction with automatic textual search or speech recognition systems. The model can be trained on large corpora of text to produce probability estimates that would improve the ability of systems to identify words in a sentence given partial contextual information. The model uses a gradient-descent learning procedure to develop a metric of similarity among terms in a corpus, based on context. Using lexical categories based on this metric, a network can then be trained to do serial word probability estimation. Such a metric can also be used to improve the performance of topic-based search by allowing retrieval of information that is related to desired topics even if no obvious set of key words unites all the retrieved items.

  7. Punctured Parallel Viterbi Decoding Of Long Constraint Length ...

    African Journals Online (AJOL)

    This paper considers puncturing applied to the parallel Viterbi decoding of long constraint length convolutional codes involving partitioning of the basic code. It is shown that the combination of the two techniques of parallel Viterbi decoding and puncturing provides a considerable reduction in decoding complexity, which ...

  8. Word translation entropy in translation

    DEFF Research Database (Denmark)

    Schaeffer, Moritz; Dragsted, Barbara; Hvelplund, Kristian Tangsgaard

    2016-01-01

    This study reports on an investigation into the relationship between the number of translation alternatives for a single word and eye movements on the source text. In addition, the effect of word order differences between source and target text on eye movements on the source text is studied. In p...

  9. Word Translation Entropy

    DEFF Research Database (Denmark)

    Schaeffer, Moritz; Dragsted, Barbara; Hvelplund, Kristian Tangsgaard

    2016-01-01

    language activation during source text reading in translation, i.e. co-activation of the two linguistic systems, employed late eye movement measures or reaction times. The current study therefore aims to investigate if and to what extent earlier eye movement measures in reading for translation show...... evidence of co-activation. Results show that the number of translation alternatives for a single word and differences between source and target text in terms of word order have an effect on very early and late eye movement measures. Results are interpreted in terms of semantic and structural cross...

  10. Word Translation Entropy

    DEFF Research Database (Denmark)

    Schaeffer, Moritz; Dragsted, Barbara; Hvelplund, Kristian Tangsgaard

    language activation during source text reading in translation, i.e. co-activation of the two linguistic systems, employed late eye movement measures or reaction times. The current study therefore aims to investigate if and to what extent earlier eye movement measures in reading for translation show...... evidence of co-activation. Results show that the number of translation alternatives for a single word and differences between source and target text in terms of word order have an effect on very early and late eye movement measures. Results are interpreted in terms of semantic and structural cross...

  11. Sarbalap! Words.

    Science.gov (United States)

    Cantu, Virginia, Comp.; And Others

    Prepared by bilingual teacher aide students, this glossary provides the Spanish translation of about 1,300 English words used in the bilingual classroom. Intended to serve as a handy reference for teachers, teacher aides, and students, the glossary can also be used in teacher training programs as a vocabulary builder for future bilingual teachers…

  12. Performance breakdown in optimal stimulus decoding

    Czech Academy of Sciences Publication Activity Database

    Košťál, Lubomír; Lánský, Petr; Pilarski, Stevan

    2015-01-01

    Roč. 12, č. 3 (2015), 036012 ISSN 1741-2560 R&D Projects: GA ČR(CZ) GA15-08066S Institutional support: RVO:67985823 Keywords : decoding accuracy * Fisher information * threshold effect Subject RIV: BD - Theory of Information Impact factor: 3.493, year: 2015

  13. Older Adults Have Difficulty in Decoding Sarcasm

    Science.gov (United States)

    Phillips, Louise H.; Allen, Roy; Bull, Rebecca; Hering, Alexandra; Kliegel, Matthias; Channon, Shelley

    2015-01-01

    Younger and older adults differ in performance on a range of social-cognitive skills, with older adults having difficulties in decoding nonverbal cues to emotion and intentions. Such skills are likely to be important when deciding whether someone is being sarcastic. In the current study we investigated in a life span sample whether there are…

  14. Turbo decoder core design for system development

    Science.gov (United States)

    Chen, Xiaoyi; Yao, Qingdong; Liu, Peng

    2003-04-01

    Due to their near Shannon-capacity performance, turbo codes have received a considerable amount of attention since their introduction. They are particularly attractive for cellular communication systems and have been included in the specifications for both the WCDMA(UMTS) and cdma2000 third-generation cellular standards. The log-MAP decoding algorithm and some technologies used to reduce the complexity have discussed in the past days. But we can see that if we apply the Turbo code to wireless communications,the decoding process rate is the bottleneck. The software implement is not realistic in today"s DSP process rate. So the hardware design is supposed to realize the decoding. The purpose of this paper is to present a full ASIC design way of Turbo decoding. Many technologies are added to the basic Log-MAP algorithm to simple the design and improve the performance. With the log-MAP algorithm, the Jacobi logarithm is computed exactly using max*()=ln(exp(x)+exp(y))=max()+fc(|y-x|),The correction function fc(|y-x|) is important because there will be 0.5dB SNR loss without it. The linear approximation can be used and the linear parameters was selected carefully to suit hardware realize in our design. In order to save the power consumption and also to assure the performance, the quantization is important in ASIC design, we adopt a compromise scheme to save the power and also there is good BER behaves. Many noisy frames can be corrected with a few iterations while some of the more noisy frames need to experience a full number of iterations (NOI). Thus, if the decoder could stop the iteration as soon as the frame becomes correct, the average NOI would be reduced. There are many ways to stop the iteration such as CRC, compare and so on, we adopt a significantly less computation and much less storage stop criteria. For long frames the memory for storing the entire frame of the forward probability α or the backward probability β can be very large. Available products all

  15. Unsupervised adaptation of brain machine interface decoders

    Directory of Open Access Journals (Sweden)

    Tayfun eGürel

    2012-11-01

    Full Text Available The performance of neural decoders can degrade over time due to nonstationarities in the relationship between neuronal activity and behavior. In this case, brain-machine interfaces (BMI require adaptation of their decoders to maintain high performance across time. One way to achieve this is by use of periodical calibration phases, during which the BMI system (or an external human demonstrator instructs the user to perform certain movements or behaviors. This approach has two disadvantages: (i calibration phases interrupt the autonomous operation of the BMI and (ii between two calibration phases the BMI performance might not be stable but continuously decrease. A better alternative would be that the BMI decoder is able to continuously adapt in an unsupervised manner during autonomous BMI operation, i.e. without knowing the movement intentions of the user. In the present article, we present an efficient method for such unsupervised training of BMI systems for continuous movement control. The proposed method utilizes a cost function derived from neuronal recordings, which guides a learning algorithm to evaluate the decoding parameters. We verify the performance of our adaptive method by simulating a BMI user with an optimal feedback control model and its interaction with our adaptive BMI decoder. The simulation results show that the cost function and the algorithm yield fast and precise trajectories towards targets at random orientations on a 2-dimensional computer screen. For initially unknown and nonstationary tuning parameters, our unsupervised method is still able to generate precise trajectories and to keep its performance stable in the long term. The algorithm can optionally work also with neuronal error signals instead or in conjunction with the proposed unsupervised adaptation.

  16. What Homophones Say about Words.

    Directory of Open Access Journals (Sweden)

    Isabelle Dautriche

    Full Text Available The number of potential meanings for a new word is astronomic. To make the word-learning problem tractable, one must restrict the hypothesis space. To do so, current word learning accounts often incorporate constraints about cognition or about the mature lexicon directly in the learning device. We are concerned with the convexity constraint, which holds that concepts (privileged sets of entities that we think of as "coherent" do not have gaps (if A and B belong to a concept, so does any entity "between" A and B. To leverage from it a linguistic constraint, learning algorithms have percolated this constraint from concepts, to word forms: some algorithms rely on the possibility that word forms are associated with convex sets of objects. Yet this does have to be the case: homophones are word forms associated with two separate words and meanings. Two sets of experiments show that when evidence suggests that a novel label is associated with a disjoint (non-convex set of objects, either a because there is a gap in conceptual space between the learning exemplars for a given word or b because of the intervention of other lexical items in that gap, adults prefer to postulate homophony, where a single word form is associated with two separate words and meanings, rather than inferring that the word could have a disjunctive, discontinuous meaning. These results about homophony must be integrated to current word learning algorithms. We conclude by arguing for a weaker specialization of word learning algorithms, which too often could miss important constraints by focusing on a restricted empirical basis (e.g., non-homophonous content words.

  17. What Homophones Say about Words.

    Science.gov (United States)

    Dautriche, Isabelle; Chemla, Emmanuel

    2016-01-01

    The number of potential meanings for a new word is astronomic. To make the word-learning problem tractable, one must restrict the hypothesis space. To do so, current word learning accounts often incorporate constraints about cognition or about the mature lexicon directly in the learning device. We are concerned with the convexity constraint, which holds that concepts (privileged sets of entities that we think of as "coherent") do not have gaps (if A and B belong to a concept, so does any entity "between" A and B). To leverage from it a linguistic constraint, learning algorithms have percolated this constraint from concepts, to word forms: some algorithms rely on the possibility that word forms are associated with convex sets of objects. Yet this does have to be the case: homophones are word forms associated with two separate words and meanings. Two sets of experiments show that when evidence suggests that a novel label is associated with a disjoint (non-convex) set of objects, either a) because there is a gap in conceptual space between the learning exemplars for a given word or b) because of the intervention of other lexical items in that gap, adults prefer to postulate homophony, where a single word form is associated with two separate words and meanings, rather than inferring that the word could have a disjunctive, discontinuous meaning. These results about homophony must be integrated to current word learning algorithms. We conclude by arguing for a weaker specialization of word learning algorithms, which too often could miss important constraints by focusing on a restricted empirical basis (e.g., non-homophonous content words).

  18. Integration of lexical and sublexical processing in the spelling of regular words: a multiple single-case study in Italian dysgraphic patients.

    Science.gov (United States)

    Laiacona, Marcella; Capitani, Erminio; Zonca, Giusy; Scola, Ilaria; Saletta, Paola; Luzzatti, Claudio

    2009-01-01

    In this study we investigated 12 cases of "mixed dysgraphia", a spelling impairment where regular words are spelt better than either ambiguous words or regular non-words. Two explanations of mixed dysgraphia were formerly offered by Luzzatti et al. (1998): (i) a double functional lesion of the orthographic output lexicon (or damage to its access) and of the acoustic-to-phonological conversion; and (ii) some kind of interaction/summation between lexical and sublexical spelling routes when processing regular words. We first analysed whether a double functional lesion was sufficient to explain the mixed dysgraphia, checking acoustic-to-phonological conversion by means of the repetition of words and non-words: the answer was positive in five cases and uncertain in three. We tested the remaining four cases to see if there was an interaction between lexical and sublexical processing of regular words, quantifying for each patient, on a probabilistic basis, the separate contribution of the residual lexical and sublexical resources. We investigated whether the processing along these routes was simultaneous but independent ("independent cooperation") or if instead there was "interaction", i.e., the simultaneous activity led to an added increase of efficiency over and above the mere combination of separate success probabilities. For one case the processing along the two routes was independent, in the other three cases an interaction resulted. Following the same approach, we found that for the five cases with a double functional lesion, the observed success on regular word spelling was higher than that expected on a probabilistic basis, but the interpretation of this finding was different.

  19. Long-term asynchronous decoding of arm motion using electrocorticographic signals in monkey

    Directory of Open Access Journals (Sweden)

    Zenas C Chao

    2010-03-01

    Full Text Available Brain–machine interfaces (BMIs employ the electrical activity generated by cortical neurons directly for controlling external devices and have been conceived as a means for restoring human cognitive or sensory-motor functions. The dominant approach in BMI research has been to decode motor variables based on single-unit activity (SUA. Unfortunately, this approach suffers from poor long-term stability and daily recalibration is normally required to maintain reliable performance. A possible alternative is BMIs based on electrocorticograms (ECoGs, which measure population activity and can provide more durable and stable recording. However, the level of long-term stability that ECoG-based decoding can offer remains unclear. Here we propose a novel ECoG-based decoding paradigm and show that we have successfully decoded hand positions and arm joint angles during an asynchronous food-reaching task in monkeys when explicit cues prompting the onset of movement were not required. Performance using our ECoG-based decoder was comparable to existing SUA-based systems while evincing far superior stability and durability. In addition, the same decoder could be used for months without any drift in accuracy or recalibration. These results were achieved by incorporating the spatio-spectro-temporal integration of activity across multiple cortical areas to compensate for the lower fidelity of ECoG signals. These results show the feasibility of high-performance, chronic and versatile ECoG-based neuroprosthetic devices for real-life applications. This new method provides a stable platform for investigating cortical correlates for understanding motor control, sensory perception, and high-level cognitive processes.

  20. Long-Term Asynchronous Decoding of Arm Motion Using Electrocorticographic Signals in Monkeys

    Science.gov (United States)

    Chao, Zenas C.; Nagasaka, Yasuo; Fujii, Naotaka

    2009-01-01

    Brain–machine interfaces (BMIs) employ the electrical activity generated by cortical neurons directly for controlling external devices and have been conceived as a means for restoring human cognitive or sensory-motor functions. The dominant approach in BMI research has been to decode motor variables based on single-unit activity (SUA). Unfortunately, this approach suffers from poor long-term stability and daily recalibration is normally required to maintain reliable performance. A possible alternative is BMIs based on electrocorticograms (ECoGs), which measure population activity and may provide more durable and stable recording. However, the level of long-term stability that ECoG-based decoding can offer remains unclear. Here we propose a novel ECoG-based decoding paradigm and show that we have successfully decoded hand positions and arm joint angles during an asynchronous food-reaching task in monkeys when explicit cues prompting the onset of movement were not required. Performance using our ECoG-based decoder was comparable to existing SUA-based systems while evincing far superior stability and durability. In addition, the same decoder could be used for months without any drift in accuracy or recalibration. These results were achieved by incorporating the spatio-spectro-temporal integration of activity across multiple cortical areas to compensate for the lower fidelity of ECoG signals. These results show the feasibility of high-performance, chronic and versatile ECoG-based neuroprosthetic devices for real-life applications. This new method provides a stable platform for investigating cortical correlates for understanding motor control, sensory perception, and high-level cognitive processes. PMID:20407639

  1. Decoding Speech With Integrated Hybrid Signals Recorded From the Human Ventral Motor Cortex

    Directory of Open Access Journals (Sweden)

    Kenji Ibayashi

    2018-04-01

    Full Text Available Restoration of speech communication for locked-in patients by means of brain computer interfaces (BCIs is currently an important area of active research. Among the neural signals obtained from intracranial recordings, single/multi-unit activity (SUA/MUA, local field potential (LFP, and electrocorticography (ECoG are good candidates for an input signal for BCIs. However, the question of which signal or which combination of the three signal modalities is best suited for decoding speech production remains unverified. In order to record SUA, LFP, and ECoG simultaneously from a highly localized area of human ventral sensorimotor cortex (vSMC, we fabricated an electrode the size of which was 7 by 13 mm containing sparsely arranged microneedle and conventional macro contacts. We determined which signal modality is the most capable of decoding speech production, and tested if the combination of these signals could improve the decoding accuracy of spoken phonemes. Feature vectors were constructed from spike frequency obtained from SUAs and event-related spectral perturbation derived from ECoG and LFP signals, then input to the decoder. The results showed that the decoding accuracy for five spoken vowels was highest when features from multiple signals were combined and optimized for each subject, and reached 59% when averaged across all six subjects. This result suggests that multi-scale signals convey complementary information for speech articulation. The current study demonstrated that simultaneous recording of multi-scale neuronal activities could raise decoding accuracy even though the recording area is limited to a small portion of cortex, which is advantageous for future implementation of speech-assisting BCIs.

  2. Decoding subjective mental states from fMRI activity patterns

    International Nuclear Information System (INIS)

    Tamaki, Masako; Kamitani, Yukiyasu

    2011-01-01

    In recent years, functional magnetic resonance imaging (fMRI) decoding has emerged as a powerful tool to read out detailed stimulus features from multi-voxel brain activity patterns. Moreover, the method has been extended to perform a primitive form of 'mind-reading,' by applying a decoder 'objectively' trained using stimulus features to more 'subjective' conditions. In this paper, we first introduce basic procedures for fMRI decoding based on machine learning techniques. Second, we discuss the source of information used for decoding, in particular, the possibility of extracting information from subvoxel neural structures. We next introduce two experimental designs for decoding subjective mental states: the 'objective-to-subjective design' and the 'subjective-to-subjective design.' Then, we illustrate recent studies on the decoding of a variety of mental states, such as, attention, awareness, decision making, memory, and mental imagery. Finally, we discuss the challenges and new directions of fMRI decoding. (author)

  3. Efficient Decoding of Turbo Codes with Nonbinary Belief Propagation

    Directory of Open Access Journals (Sweden)

    Thierry Lestable

    2008-05-01

    Full Text Available This paper presents a new approach to decode turbo codes using a nonbinary belief propagation decoder. The proposed approach can be decomposed into two main steps. First, a nonbinary Tanner graph representation of the turbo code is derived by clustering the binary parity-check matrix of the turbo code. Then, a group belief propagation decoder runs several iterations on the obtained nonbinary Tanner graph. We show in particular that it is necessary to add a preprocessing step on the parity-check matrix of the turbo code in order to ensure good topological properties of the Tanner graph and then good iterative decoding performance. Finally, by capitalizing on the diversity which comes from the existence of distinct efficient preprocessings, we propose a new decoding strategy, called decoder diversity, that intends to take benefits from the diversity through collaborative decoding schemes.

  4. SYMBOL LEVEL DECODING FOR DUO-BINARY TURBO CODES

    Directory of Open Access Journals (Sweden)

    Yogesh Beeharry

    2017-05-01

    Full Text Available This paper investigates the performance of three different symbol level decoding algorithms for Duo-Binary Turbo codes. Explicit details of the computations involved in the three decoding techniques, and a computational complexity analysis are given. Simulation results with different couple lengths, code-rates, and QPSK modulation reveal that the symbol level decoding with bit-level information outperforms the symbol level decoding by 0.1 dB on average in the error floor region. Moreover, a complexity analysis reveals that symbol level decoding with bit-level information reduces the decoding complexity by 19.6 % in terms of the total number of computations required for each half-iteration as compared to symbol level decoding.

  5. Decoding Pigeon Behavior Outcomes Using Functional Connections among Local Field Potentials.

    Science.gov (United States)

    Chen, Yan; Liu, Xinyu; Li, Shan; Wan, Hong

    2018-01-01

    Recent studies indicate that the local field potential (LFP) carries information about an animal's behavior, but issues regarding whether there are any relationships between the LFP functional networks and behavior tasks as well as whether it is possible to employ LFP network features to decode the behavioral outcome in a single trial remain unresolved. In this study, we developed a network-based method to decode the behavioral outcomes in pigeons by using the functional connectivity strength values among LFPs recorded from the nidopallium caudolaterale (NCL). In our method, the functional connectivity strengths were first computed based on the synchronization likelihood. Second, the strength values were unwrapped into row vectors and their dimensions were then reduced by principal component analysis. Finally, the behavioral outcomes in single trials were decoded using leave-one-out combined with the k -nearest neighbor method. The results showed that the LFP functional network based on the gamma-band was related to the goal-directed behavior of pigeons. Moreover, the accuracy of the network features (74 ± 8%) was significantly higher than that of the power features (61 ± 12%). The proposed method provides a powerful tool for decoding animal behavior outcomes using a neural functional network.

  6. Word wheels

    CERN Document Server

    Clark, Kathryn

    2013-01-01

    Targeting the specific problems learners have with language structure, these multi-sensory exercises appeal to all age groups including adults. Exercises use sight, sound and touch and are also suitable for English as an Additional Lanaguage and Basic Skills students.Word Wheels includes off-the-shelf resources including lesson plans and photocopiable worksheets, an interactive CD with practice exercises, and support material for the busy teacher or non-specialist staff, as well as homework activities.

  7. Fast bootstrapping and permutation testing for assessing reproducibility and interpretability of multivariate fMRI decoding models.

    Directory of Open Access Journals (Sweden)

    Bryan R Conroy

    Full Text Available Multivariate decoding models are increasingly being applied to functional magnetic imaging (fMRI data to interpret the distributed neural activity in the human brain. These models are typically formulated to optimize an objective function that maximizes decoding accuracy. For decoding models trained on full-brain data, this can result in multiple models that yield the same classification accuracy, though some may be more reproducible than others--i.e. small changes to the training set may result in very different voxels being selected. This issue of reproducibility can be partially controlled by regularizing the decoding model. Regularization, along with the cross-validation used to estimate decoding accuracy, typically requires retraining many (often on the order of thousands of related decoding models. In this paper we describe an approach that uses a combination of bootstrapping and permutation testing to construct both a measure of cross-validated prediction accuracy and model reproducibility of the learned brain maps. This requires re-training our classification method on many re-sampled versions of the fMRI data. Given the size of fMRI datasets, this is normally a time-consuming process. Our approach leverages an algorithm called fast simultaneous training of generalized linear models (FaSTGLZ to create a family of classifiers in the space of accuracy vs. reproducibility. The convex hull of this family of classifiers can be used to identify a subset of Pareto optimal classifiers, with a single-optimal classifier selectable based on the relative cost of accuracy vs. reproducibility. We demonstrate our approach using full-brain analysis of elastic-net classifiers trained to discriminate stimulus type in an auditory and visual oddball event-related fMRI design. Our approach and results argue for a computational approach to fMRI decoding models in which the value of the interpretation of the decoding model ultimately depends upon optimizing a

  8. Computerized trainings in four groups of struggling readers: Specific effects on word reading and comprehension.

    Science.gov (United States)

    Potocki, Anna; Magnan, Annie; Ecalle, Jean

    2015-01-01

    Four groups of poor readers were identified among a population of students with learning disabilities attending a special class in secondary school: normal readers; specific poor decoders; specific poor comprehenders, and general poor readers (deficits in both decoding and comprehension). These students were then trained with a software program designed to encourage either their word decoding skills or their text comprehension skills. After 5 weeks of training, we observed that the students experiencing word reading deficits and trained with the decoding software improved primarily in the reading fluency task while those exhibiting comprehension deficits and trained with the comprehension software showed improved performance in listening and reading comprehension. But interestingly, the latter software also led to improved performance on the word recognition task. This result suggests that, for these students, training interventions focused at the text level and its comprehension might be more beneficial for reading in general (i.e., for the two components of reading) than word-level decoding trainings. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Comparison of the effects of two phonics training programs on L2 word reading.

    Science.gov (United States)

    Chu, Min-Chin; Chen, Shu-Hui

    2014-02-01

    Empirical evidence shows that explicit phonics teaching is beneficial for English word reading. However, there has been controversy as to whether phonics teaching should incorporate meaning-involved decodable text instruction to facilitate children's word reading. This study compares the effects of phonics teaching with and without decodable text instruction on immediate and delayed English word reading in 117 Taiwanese children learning English, assigned to a Phonics-only group (n = 58) and a phonics plus decodable text instruction (Phonics+) group (n = 59). Results showed that although both groups significantly improved in immediate and delayed post-test word reading, the Phonics+ group performed better in both post-tests, but the difference was significant only in the delayed word reading, suggesting a better long-term retention effect produced by Phonics+ teaching. These indicated that incorporated meaning-involved decodable text reading might offer another better facilitative linking route for English word reading even for non-alphabetic child learners of English. The findings were discussed from linguistic, psycholinguistic, and reading perspectives, with implications drawn for second/foreign language teaching and research in reading instruction.

  10. IV. NIH Toolbox Cognition Battery (CB): measuring language (vocabulary comprehension and reading decoding).

    Science.gov (United States)

    Gershon, Richard C; Slotkin, Jerry; Manly, Jennifer J; Blitz, David L; Beaumont, Jennifer L; Schnipke, Deborah; Wallner-Allen, Kathleen; Golinkoff, Roberta Michnick; Gleason, Jean Berko; Hirsh-Pasek, Kathy; Adams, Marilyn Jager; Weintraub, Sandra

    2013-08-01

    Mastery of language skills is an important predictor of daily functioning and health. Vocabulary comprehension and reading decoding are relatively quick and easy to measure and correlate highly with overall cognitive functioning, as well as with success in school and work. New measures of vocabulary comprehension and reading decoding (in both English and Spanish) were developed for the NIH Toolbox Cognition Battery (CB). In the Toolbox Picture Vocabulary Test (TPVT), participants hear a spoken word while viewing four pictures, and then must choose the picture that best represents the word. This approach tests receptive vocabulary knowledge without the need to read or write, removing the literacy load for children who are developing literacy and for adults who struggle with reading and writing. In the Toolbox Oral Reading Recognition Test (TORRT), participants see a letter or word onscreen and must pronounce or identify it. The examiner determines whether it was pronounced correctly by comparing the response to the pronunciation guide on a separate computer screen. In this chapter, we discuss the importance of language during childhood and the relation of language and brain function. We also review the development of the TPVT and TORRT, including information about the item calibration process and results from a validation study. Finally, the strengths and weaknesses of the measures are discussed. © 2013 The Society for Research in Child Development, Inc.

  11. Word length effects on novel words: evidence from eye movements.

    Science.gov (United States)

    Lowell, Randy; Morris, Robin K

    2014-01-01

    The present study investigated the effects of word length on eye movement behavior during initial processing of novel words while reading. Adult skilled readers' eye movements were monitored as they read novel or known target words in sentence frames with neutral context preceding the target word. Comparable word length effects on all single-fixation measures for novel and known words suggested that both types of words were subject to similar initial encoding strategies. The impact of the absence of an existing lexical entry emerged in multiple first-pass fixation measures in the form of interactions between word length (long and short) and word type (novel and known). Specifically, readers spent significantly more first-pass time refixating long novel targets than short novel targets; however, the first-pass time spent refixating known controls did not differ as a function of length. Implications of these findings for models of eye movement control while reading, as well as for vocabulary acquisition in reading, are discussed.

  12. Neural decoding of visual imagery during sleep.

    Science.gov (United States)

    Horikawa, T; Tamaki, M; Miyawaki, Y; Kamitani, Y

    2013-05-03

    Visual imagery during sleep has long been a topic of persistent speculation, but its private nature has hampered objective analysis. Here we present a neural decoding approach in which machine-learning models predict the contents of visual imagery during the sleep-onset period, given measured brain activity, by discovering links between human functional magnetic resonance imaging patterns and verbal reports with the assistance of lexical and image databases. Decoding models trained on stimulus-induced brain activity in visual cortical areas showed accurate classification, detection, and identification of contents. Our findings demonstrate that specific visual experience during sleep is represented by brain activity patterns shared by stimulus perception, providing a means to uncover subjective contents of dreaming using objective neural measurement.

  13. A fast and accurate decoder for underwater acoustic telemetry.

    Science.gov (United States)

    Ingraham, J M; Deng, Z D; Li, X; Fu, T; McMichael, G A; Trumbo, B A

    2014-07-01

    The Juvenile Salmon Acoustic Telemetry System, developed by the U.S. Army Corps of Engineers, Portland District, has been used to monitor the survival of juvenile salmonids passing through hydroelectric facilities in the Federal Columbia River Power System. Cabled hydrophone arrays deployed at dams receive coded transmissions sent from acoustic transmitters implanted in fish. The signals' time of arrival on different hydrophones is used to track fish in 3D. In this article, a new algorithm that decodes the received transmissions is described and the results are compared to results for the previous decoding algorithm. In a laboratory environment, the new decoder was able to decode signals with lower signal strength than the previous decoder, effectively increasing decoding efficiency and range. In field testing, the new algorithm decoded significantly more signals than the previous decoder and three-dimensional tracking experiments showed that the new decoder's time-of-arrival estimates were accurate. At multiple distances from hydrophones, the new algorithm tracked more points more accurately than the previous decoder. The new algorithm was also more than 10 times faster, which is critical for real-time applications on an embedded system.

  14. On Lattice Sequential Decoding for The Unconstrained AWGN Channel

    KAUST Repository

    Abediseid, Walid

    2012-10-01

    In this paper, the performance limits and the computational complexity of the lattice sequential decoder are analyzed for the unconstrained additive white Gaussian noise channel. The performance analysis available in the literature for such a channel has been studied only under the use of the minimum Euclidean distance decoder that is commonly referred to as the lattice decoder. Lattice decoders based on solutions to the NP-hard closest vector problem are very complex to implement, and the search for low complexity receivers for the detection of lattice codes is considered a challenging problem. However, the low computational complexity advantage that sequential decoding promises, makes it an alternative solution to the lattice decoder. In this work, we characterize the performance and complexity tradeoff via the error exponent and the decoding complexity, respectively, of such a decoder as a function of the decoding parameter --- the bias term. For the above channel, we derive the cut-off volume-to-noise ratio that is required to achieve a good error performance with low decoding complexity.

  15. On Lattice Sequential Decoding for The Unconstrained AWGN Channel

    KAUST Repository

    Abediseid, Walid

    2013-04-04

    In this paper, the performance limits and the computational complexity of the lattice sequential decoder are analyzed for the unconstrained additive white Gaussian noise channel. The performance analysis available in the literature for such a channel has been studied only under the use of the minimum Euclidean distance decoder that is commonly referred to as the \\\\textit{lattice decoder}. Lattice decoders based on solutions to the NP-hard closest vector problem are very complex to implement, and the search for low complexity receivers for the detection of lattice codes is considered a challenging problem. However, the low computational complexity advantage that sequential decoding promises, makes it an alternative solution to the lattice decoder. In this work, we characterize the performance and complexity tradeoff via the error exponent and the decoding complexity, respectively, of such a decoder as a function of the decoding parameter --- the bias term. For the above channel, we derive the cut-off volume-to-noise ratio that is required to achieve a good error performance with low decoding complexity.

  16. Novel LDPC Decoder via MLP Neural Networks

    OpenAIRE

    Karami, Alireza; Attari, Mahmoud Ahmadian

    2014-01-01

    In this paper, a new method for decoding Low Density Parity Check (LDPC) codes, based on Multi-Layer Perceptron (MLP) neural networks is proposed. Due to the fact that in neural networks all procedures are processed in parallel, this method can be considered as a viable alternative to Message Passing Algorithm (MPA), with high computational complexity. Our proposed algorithm runs with soft criterion and concurrently does not use probabilistic quantities to decide what the estimated codeword i...

  17. Word Domain Disambiguation via Word Sense Disambiguation

    Energy Technology Data Exchange (ETDEWEB)

    Sanfilippo, Antonio P.; Tratz, Stephen C.; Gregory, Michelle L.

    2006-06-04

    Word subject domains have been widely used to improve the perform-ance of word sense disambiguation al-gorithms. However, comparatively little effort has been devoted so far to the disambiguation of word subject do-mains. The few existing approaches have focused on the development of al-gorithms specific to word domain dis-ambiguation. In this paper we explore an alternative approach where word domain disambiguation is achieved via word sense disambiguation. Our study shows that this approach yields very strong results, suggesting that word domain disambiguation can be ad-dressed in terms of word sense disam-biguation with no need for special purpose algorithms.

  18. Sequential decoders for large MIMO systems

    KAUST Repository

    Ali, Konpal S.

    2014-05-01

    Due to their ability to provide high data rates, multiple-input multiple-output (MIMO) systems have become increasingly popular. Decoding of these systems with acceptable error performance is computationally very demanding. In this paper, we employ the Sequential Decoder using the Fano Algorithm for large MIMO systems. A parameter called the bias is varied to attain different performance-complexity trade-offs. Low values of the bias result in excellent performance but at the expense of high complexity and vice versa for higher bias values. Numerical results are done that show moderate bias values result in a decent performance-complexity trade-off. We also attempt to bound the error by bounding the bias, using the minimum distance of a lattice. The variations in complexity with SNR have an interesting trend that shows room for considerable improvement. Our work is compared against linear decoders (LDs) aided with Element-based Lattice Reduction (ELR) and Complex Lenstra-Lenstra-Lovasz (CLLL) reduction. © 2014 IFIP.

  19. Exploring the word superiority effect using TVA

    DEFF Research Database (Denmark)

    Starrfelt, Randi

    for perception of words, or a higher speed of processing for words than letters. We have investigated the WSE using methods based on a Theory of Visual Attention. In an experiment using single stimuli (words or letters) presented centrally, we show that the classical WSE is specifically reflected in perceptual......Words are made of letters, and yet sometimes it is easier to identify a word than a single letter. This word superiority effect (WSE) has been observed when written stimuli are presented very briefly or degraded by visual noise. It is unclear, however, if this is due to a lower threshold...... simultaneously we find a different pattern: In a whole report experiment with six stimuli (letters or words), letters are perceived more easily than words, and this is reflected both in perceptual processing speed and short term memory capacity....

  20. Generalized instantly decodable network coding for relay-assisted networks

    KAUST Repository

    Elmahdy, Adel M.

    2013-09-01

    In this paper, we investigate the problem of minimizing the frame completion delay for Instantly Decodable Network Coding (IDNC) in relay-assisted wireless multicast networks. We first propose a packet recovery algorithm in the single relay topology which employs generalized IDNC instead of strict IDNC previously proposed in the literature for the same relay-assisted topology. This use of generalized IDNC is supported by showing that it is a super-set of the strict IDNC scheme, and thus can generate coding combinations that are at least as efficient as strict IDNC in reducing the average completion delay. We then extend our study to the multiple relay topology and propose a joint generalized IDNC and relay selection algorithm. This proposed algorithm benefits from the reception diversity of the multiple relays to further reduce the average completion delay in the network. Simulation results show that our proposed solutions achieve much better performance compared to previous solutions in the literature. © 2013 IEEE.

  1. Visual word learning in adults with dyslexia

    Directory of Open Access Journals (Sweden)

    Rosa Kit Wan Kwok

    2014-05-01

    Full Text Available We investigated word learning in university and college students with a diagnosis of dyslexia and in typically-reading controls. Participants read aloud short (4-letter and longer (7-letter nonwords as quickly as possible. The nonwords were repeated across 10 blocks, using a different random order in each block. Participants returned 7 days later and repeated the experiment. Accuracy was high in both groups. The dyslexics were substantially slower than the controls at reading the nonwords throughout the experiment. They also showed a larger length effect, indicating less effective decoding skills. Learning was demonstrated by faster reading of the nonwords across repeated presentations and by a reduction in the difference in reading speeds between shorter and longer nonwords. The dyslexics required more presentations of the nonwords before the length effect became non-significant, only showing convergence in reaction times between shorter and longer items in the second testing session where controls achieved convergence part-way through the first session. Participants also completed a psychological test battery assessing reading and spelling, vocabulary, phonological awareness, working memory, nonverbal ability and motor speed. The dyslexics performed at a similar level to the controls on nonverbal ability but significantly less well on all the other measures. Regression analyses found that decoding ability, measured as the speed of reading aloud nonwords when they were presented for the first time, was predicted by a composite of word reading and spelling scores (‘literacy’. Word learning was assessed in terms of the improvement in naming speeds over 10 blocks of training. Learning was predicted by vocabulary and working memory scores, but not by literacy, phonological awareness, nonverbal ability or motor speed. The results show that young dyslexic adults have problems both in pronouncing novel words and in learning new written words.

  2. A Tensor-Product-Kernel Framework for Multiscale Neural Activity Decoding and Control

    Science.gov (United States)

    Li, Lin; Brockmeier, Austin J.; Choi, John S.; Francis, Joseph T.; Sanchez, Justin C.; Príncipe, José C.

    2014-01-01

    Brain machine interfaces (BMIs) have attracted intense attention as a promising technology for directly interfacing computers or prostheses with the brain's motor and sensory areas, thereby bypassing the body. The availability of multiscale neural recordings including spike trains and local field potentials (LFPs) brings potential opportunities to enhance computational modeling by enriching the characterization of the neural system state. However, heterogeneity on data type (spike timing versus continuous amplitude signals) and spatiotemporal scale complicates the model integration of multiscale neural activity. In this paper, we propose a tensor-product-kernel-based framework to integrate the multiscale activity and exploit the complementary information available in multiscale neural activity. This provides a common mathematical framework for incorporating signals from different domains. The approach is applied to the problem of neural decoding and control. For neural decoding, the framework is able to identify the nonlinear functional relationship between the multiscale neural responses and the stimuli using general purpose kernel adaptive filtering. In a sensory stimulation experiment, the tensor-product-kernel decoder outperforms decoders that use only a single neural data type. In addition, an adaptive inverse controller for delivering electrical microstimulation patterns that utilizes the tensor-product kernel achieves promising results in emulating the responses to natural stimulation. PMID:24829569

  3. Decoding of intended saccade direction in an oculomotor brain-computer interface

    Science.gov (United States)

    Jia, Nan; Brincat, Scott L.; Salazar-Gómez, Andrés F.; Panko, Mikhail; Guenther, Frank H.; Miller, Earl K.

    2017-08-01

    Objective. To date, invasive brain-computer interface (BCI) research has largely focused on replacing lost limb functions using signals from the hand/arm areas of motor cortex. However, the oculomotor system may be better suited to BCI applications involving rapid serial selection from spatial targets, such as choosing from a set of possible words displayed on a computer screen in an augmentative and alternative communication (AAC) application. Here we aimed to demonstrate the feasibility of a BCI utilizing the oculomotor system. Approach. We developed a chronic intracortical BCI in monkeys to decode intended saccadic eye movement direction using activity from multiple frontal cortical areas. Main results. Intended saccade direction could be decoded in real time with high accuracy, particularly at contralateral locations. Accurate decoding was evident even at the beginning of the BCI session; no extensive BCI experience was necessary. High-frequency (80-500 Hz) local field potential magnitude provided the best performance, even over spiking activity, thus simplifying future BCI applications. Most of the information came from the frontal and supplementary eye fields, with relatively little contribution from dorsolateral prefrontal cortex. Significance. Our results support the feasibility of high-accuracy intracortical oculomotor BCIs that require little or no practice to operate and may be ideally suited for ‘point and click’ computer operation as used in most current AAC systems.

  4. Performance of students with and without reading difficulties on decoding tasks.

    Science.gov (United States)

    Nepomuceno, Pablo Felicio; Avila, Clara Regina Brandão de

    2013-01-01

    To characterize the performance of students with and without reading difficulties in reading decoding tasks to investigate parameters that can facilitate reading assessment. Forty-eight school children, from 7 to 10 years old, who attended 2nd to 4th of Elementary Schoolgrades were studied. Based on their teacher's information, the children were divided into two groups: without reading difficulty (WRDG) and with reading difficulty (RDG). Thirty-six linguistic items were selected (words and pseudowords) and presented whole or segmented (letters and syllables) to assess the children's reading. The data were compared and statistically analyzed by Mann-Whitney and Friedman Tests. The hits, as well as sensitivity and specificity, were calculated. WRDG had a better performance than RDG in all the tasks except whole pseudowords recognition. WRDG performed similarly in all the tasks. The RDG had more difficulty in reading pseudowords, particularly when presented syllable-by-syllable and letter-by-letter. Thirty-two point five proved to be a sensitive turning point: most of the children who decoded and read at least 32 items had been considered adequate by their teachers whereas most of those who did not had been classified by their teachers as having academic difficulty. The WRDG performance in decoding reading was homogeneous and better than that of the RDG. The RDG performed worse on reading segmented items, particulary on pseudowords.

  5. The Separability of Morphological Processes from Semantic Meaning and Syntactic Class in Production of Single Words: Evidence from the Hebrew Root Morpheme

    Science.gov (United States)

    Deutsch, Avital

    2016-01-01

    In the present study we investigated to what extent the morphological facilitation effect induced by the derivational root morpheme in Hebrew is independent of semantic meaning and grammatical information of the part of speech involved. Using the picture-word interference paradigm with auditorily presented distractors, Experiment 1 compared the…

  6. Decoding Delay Controlled Completion Time Reduction in Instantly Decodable Network Coding

    KAUST Repository

    Douik, Ahmed

    2016-06-27

    For several years, the completion time and the decoding delay problems in Instantly Decodable Network Coding (IDNC) were considered separately and were thought to act completely against each other. Recently, some works aimed to balance the effects of these two important IDNC metrics but none of them studied a further optimization of one by controlling the other. This paper investigates the effect of controlling the decoding delay to reduce the completion time below its currently best-known solution in both perfect and imperfect feedback with persistent erasure channels. To solve the problem, the decodingdelay- dependent expressions of the users’ and overall completion times are derived in the complete feedback scenario. Although using such expressions to find the optimal overall completion time is NP-hard, the paper proposes two novel heuristics that minimizes the probability of increasing the maximum of these decoding-delay-dependent completion time expressions after each transmission through a layered control of their decoding delays. Afterward, the paper extends the study to the imperfect feedback scenario in which uncertainties at the sender affects its ability to anticipate accurately the decoding delay increase at each user. The paper formulates the problem in such environment and derives the expression of the minimum increase in the completion time. Simulation results show the performance of the proposed solutions and suggest that both heuristics achieves a lower mean completion time as compared to the best-known heuristics for the completion time reduction in perfect and imperfect feedback. The gap in performance becomes more significant as the erasure of the channel increases.

  7. Design of 10Gbps optical encoder/decoder structure for FE-OCDMA system using SOA and opto-VLSI processors.

    Science.gov (United States)

    Aljada, Muhsen; Hwang, Seow; Alameh, Kamal

    2008-01-21

    In this paper we propose and experimentally demonstrate a reconfigurable 10Gbps frequency-encoded (1D) encoder/decoder structure for optical code division multiple access (OCDMA). The encoder is constructed using a single semiconductor optical amplifier (SOA) and 1D reflective Opto-VLSI processor. The SOA generates broadband amplified spontaneous emission that is dynamically sliced using digital phase holograms loaded onto the Opto-VLSI processor to generate 1D codewords. The selected wavelengths are injected back into the same SOA for amplifications. The decoder is constructed using single Opto-VLSI processor only. The encoded signal can successfully be retrieved at the decoder side only when the digital phase holograms of the encoder and the decoder are matched. The system performance is measured in terms of the auto-correlation and cross-correlation functions as well as the eye diagram.

  8. Deep Learning Methods for Improved Decoding of Linear Codes

    Science.gov (United States)

    Nachmani, Eliya; Marciano, Elad; Lugosch, Loren; Gross, Warren J.; Burshtein, David; Be'ery, Yair

    2018-02-01

    The problem of low complexity, close to optimal, channel decoding of linear codes with short to moderate block length is considered. It is shown that deep learning methods can be used to improve a standard belief propagation decoder, despite the large example space. Similar improvements are obtained for the min-sum algorithm. It is also shown that tying the parameters of the decoders across iterations, so as to form a recurrent neural network architecture, can be implemented with comparable results. The advantage is that significantly less parameters are required. We also introduce a recurrent neural decoder architecture based on the method of successive relaxation. Improvements over standard belief propagation are also observed on sparser Tanner graph representations of the codes. Furthermore, we demonstrate that the neural belief propagation decoder can be used to improve the performance, or alternatively reduce the computational complexity, of a close to optimal decoder of short BCH codes.

  9. A quantum algorithm for Viterbi decoding of classical convolutional codes

    OpenAIRE

    Grice, Jon R.; Meyer, David A.

    2014-01-01

    We present a quantum Viterbi algorithm (QVA) with better than classical performance under certain conditions. In this paper the proposed algorithm is applied to decoding classical convolutional codes, for instance; large constraint length $Q$ and short decode frames $N$. Other applications of the classical Viterbi algorithm where $Q$ is large (e.g. speech processing) could experience significant speedup with the QVA. The QVA exploits the fact that the decoding trellis is similar to the butter...

  10. On the role of articulatory prosodies in German message decoding.

    Science.gov (United States)

    Kohler, Klaus J; Niebuhr, Oliver

    2011-01-01

    A theoretical framework for speech reduction is outlined in which 'coarticulation' and 'articulatory control' operate on sequences of 'opening-closing gestures' in linguistic and communicative settings, leading to suprasegmental properties - 'articulatory prosodies' - in the acoustic output. In linking this gestalt perspective in speech production to the role of phonetic detail in speech understanding, this paper reports on perception experiments that test listeners' reactions to varying extension of an 'articulatory prosody of palatality' in message identification. The point of departure for the experimental design was the German utterance ich kann Ihnen das ja mal sagen 'I can mention this to you' from the Kiel Corpus of Spontaneous Speech, which contains the palatalized stretch [k̟(h)ε̈n(j)n(j)əs] for the sequence of function words /kan i.n(kə)n das/ kann Ihnen das. The utterance also makes sense without the personal pronoun Ihnen. Systematic experimental variation has shown that the extent of palatality has a highly significant influence on the decoding of Ihnen and that the effect of nasal consonant duration depends on the extension of palatality. These results are discussed in a plea to base future speech perception research on a paradigm that makes the traditional segment-prosody divide more permeable, and moves away from the generally practised phoneme orientation. Copyright © 2011 S. Karger AG, Basel.

  11. Interpolation decoding method with variable parameters for fractal image compression

    International Nuclear Information System (INIS)

    He Chuanjiang; Li Gaoping; Shen Xiaona

    2007-01-01

    The interpolation fractal decoding method, which is introduced by [He C, Yang SX, Huang X. Progressive decoding method for fractal image compression. IEE Proc Vis Image Signal Process 2004;3:207-13], involves generating progressively the decoded image by means of an interpolation iterative procedure with a constant parameter. It is well-known that the majority of image details are added at the first steps of iterations in the conventional fractal decoding; hence the constant parameter for the interpolation decoding method must be set as a smaller value in order to achieve a better progressive decoding. However, it needs to take an extremely large number of iterations to converge. It is thus reasonable for some applications to slow down the iterative process at the first stages of decoding and then to accelerate it afterwards (e.g., at some iteration as we need). To achieve the goal, this paper proposed an interpolation decoding scheme with variable (iteration-dependent) parameters and proved the convergence of the decoding process mathematically. Experimental results demonstrate that the proposed scheme has really achieved the above-mentioned goal

  12. Sub-quadratic decoding of one-point hermitian codes

    DEFF Research Database (Denmark)

    Nielsen, Johan Sebastian Rosenkilde; Beelen, Peter

    2015-01-01

    We present the first two sub-quadratic complexity decoding algorithms for one-point Hermitian codes. The first is based on a fast realization of the Guruswami-Sudan algorithm using state-of-the-art algorithms from computer algebra for polynomial-ring matrix minimization. The second is a power...... decoding algorithm: an extension of classical key equation decoding which gives a probabilistic decoding algorithm up to the Sudan radius. We show how the resulting key equations can be solved by the matrix minimization algorithms from computer algebra, yielding similar asymptotic complexities....

  13. Joint Decoding of Concatenated VLEC and STTC System

    Directory of Open Access Journals (Sweden)

    Chen Huijun

    2008-01-01

    Full Text Available Abstract We consider the decoding of wireless communication systems with both source coding in the application layer and channel coding in the physical layer for high-performance transmission over fading channels. Variable length error correcting codes (VLECs and space time trellis codes (STTCs are used to provide bandwidth efficient data compression as well as coding and diversity gains. At the receiver, an iterative joint source and space time decoding scheme are developed to utilize redundancy in both STTC and VLEC to improve overall decoding performance. Issues such as the inseparable systematic information in the symbol level, the asymmetric trellis structure of VLEC, and information exchange between bit and symbol domains have been considered in the maximum a posteriori probability (MAP decoding algorithm. Simulation results indicate that the developed joint decoding scheme achieves a significant decoding gain over the separate decoding in fading channels, whether or not the channel information is perfectly known at the receiver. Furthermore, how rate allocation between STTC and VLEC affects the performance of the joint source and space-time decoder is investigated. Different systems with a fixed overall information rate are studied. It is shown that for a system with more redundancy dedicated to the source code and a higher order modulation of STTC, the joint decoding yields better performance, though with increased complexity.

  14. Joint Decoding of Concatenated VLEC and STTC System

    Directory of Open Access Journals (Sweden)

    Huijun Chen

    2008-07-01

    Full Text Available We consider the decoding of wireless communication systems with both source coding in the application layer and channel coding in the physical layer for high-performance transmission over fading channels. Variable length error correcting codes (VLECs and space time trellis codes (STTCs are used to provide bandwidth efficient data compression as well as coding and diversity gains. At the receiver, an iterative joint source and space time decoding scheme are developed to utilize redundancy in both STTC and VLEC to improve overall decoding performance. Issues such as the inseparable systematic information in the symbol level, the asymmetric trellis structure of VLEC, and information exchange between bit and symbol domains have been considered in the maximum a posteriori probability (MAP decoding algorithm. Simulation results indicate that the developed joint decoding scheme achieves a significant decoding gain over the separate decoding in fading channels, whether or not the channel information is perfectly known at the receiver. Furthermore, how rate allocation between STTC and VLEC affects the performance of the joint source and space-time decoder is investigated. Different systems with a fixed overall information rate are studied. It is shown that for a system with more redundancy dedicated to the source code and a higher order modulation of STTC, the joint decoding yields better performance, though with increased complexity.

  15. Long-term decoding of movement force and direction with a wireless myoelectric implant

    Science.gov (United States)

    Morel, Pierre; Ferrea, Enrico; Taghizadeh-Sarshouri, Bahareh; Marcel Cardona Audí, Josep; Ruff, Roman; Hoffmann, Klaus-Peter; Lewis, Sören; Russold, Michael; Dietl, Hans; Abu-Saleh, Lait; Schroeder, Dietmar; Krautschneider, Wolfgang; Meiners, Thomas; Gail, Alexander

    2016-02-01

    Objective. The ease of use and number of degrees of freedom of current myoelectric hand prostheses is limited by the information content and reliability of the surface electromyography (sEMG) signals used to control them. For example, cross-talk limits the capacity to pick up signals from small or deep muscles, such as the forearm muscles for distal arm amputations, or sites of targeted muscle reinnervation (TMR) for proximal amputations. Here we test if signals recorded from the fully implanted, induction-powered wireless Myoplant system allow long-term decoding of continuous as well as discrete movement parameters with better reliability than equivalent sEMG recordings. The Myoplant system uses a centralized implant to transmit broadband EMG activity from four distributed bipolar epimysial electrodes. Approach. Two Rhesus macaques received implants in their backs, while electrodes were placed in their upper arm. One of the monkeys was trained to do a cursor task via a haptic robot, allowing us to control the forces exerted by the animal during arm movements. The second animal was trained to perform a center-out reaching task on a touchscreen. We compared the implanted system with concurrent sEMG recordings by evaluating our ability to decode time-varying force in one animal and discrete reach directions in the other from multiple features extracted from the raw EMG signals. Main results. In both cases, data from the implant allowed a decoder trained with data from a single day to maintain an accurate decoding performance during the following months, which was not the case for concurrent surface EMG recordings conducted simultaneously over the same muscles. Significance. These results show that a fully implantable, centralized wireless EMG system is particularly suited for long-term stable decoding of dynamic movements in demanding applications such as advanced forelimb prosthetics in a wide range of configurations (distal amputations, TMR).

  16. Distinct neural patterns enable grasp types decoding in monkey dorsal premotor cortex

    Science.gov (United States)

    Hao, Yaoyao; Zhang, Qiaosheng; Controzzi, Marco; Cipriani, Christian; Li, Yue; Li, Juncheng; Zhang, Shaomin; Wang, Yiwen; Chen, Weidong; Chiara Carrozza, Maria; Zheng, Xiaoxiang

    2014-12-01

    Objective. Recent studies have shown that dorsal premotor cortex (PMd), a cortical area in the dorsomedial grasp pathway, is involved in grasp movements. However, the neural ensemble firing property of PMd during grasp movements and the extent to which it can be used for grasp decoding are still unclear. Approach. To address these issues, we used multielectrode arrays to record both spike and local field potential (LFP) signals in PMd in macaque monkeys performing reaching and grasping of one of four differently shaped objects. Main results. Single and population neuronal activity showed distinct patterns during execution of different grip types. Cluster analysis of neural ensemble signals indicated that the grasp related patterns emerged soon (200-300 ms) after the go cue signal, and faded away during the hold period. The timing and duration of the patterns varied depending on the behaviors of individual monkey. Application of support vector machine model to stable activity patterns revealed classification accuracies of 94% and 89% for each of the two monkeys, indicating a robust, decodable grasp pattern encoded in the PMd. Grasp decoding using LFPs, especially the high-frequency bands, also produced high decoding accuracies. Significance. This study is the first to specify the neuronal population encoding of grasp during the time course of grasp. We demonstrate high grasp decoding performance in PMd. These findings, combined with previous evidence for reach related modulation studies, suggest that PMd may play an important role in generation and maintenance of grasp action and may be a suitable locus for brain-machine interface applications.

  17. Sudan-decoding generalized geometric Goppa codes

    DEFF Research Database (Denmark)

    Heydtmann, Agnes Eileen

    2003-01-01

    Generalized geometric Goppa codes are vector spaces of n-tuples with entries from different extension fields of a ground field. They are derived from evaluating functions similar to conventional geometric Goppa codes, but allowing evaluation in places of arbitrary degree. A decoding scheme...... for these codes based on Sudan's improved algorithm is presented and its error-correcting capacity is analyzed. For the implementation of the algorithm it is necessary that the so-called increasing zero bases of certain spaces of functions are available. A method to obtain such bases is developed....

  18. Word, Words, Words: Ellul and the Mediocritization of Language

    Science.gov (United States)

    Foltz, Franz; Foltz, Frederick

    2012-01-01

    The authors explore how technique via propaganda has replaced the word with images creating a mass society and limiting the ability of people to act as individuals. They begin by looking at how words affect human society and how they have changed over time. They explore how technology has altered the meaning of words in order to create a more…

  19. Deep generative learning of location-invariant visual word recognition

    Directory of Open Access Journals (Sweden)

    Maria Grazia eDi Bono

    2013-09-01

    Full Text Available It is widely believed that orthographic processing implies an approximate, flexible coding of letter position, as shown by relative-position and transposition priming effects in visual word recognition. These findings have inspired alternative proposals about the representation of letter position, ranging from noisy coding across the ordinal positions to relative position coding based on open bigrams. This debate can be cast within the broader problem of learning location-invariant representations of written words, that is, a coding scheme abstracting the identity and position of letters (and combinations of letters from their eye-centred (i.e., retinal locations. We asked whether location-invariance would emerge from deep unsupervised learning on letter strings and what type of intermediate coding would emerge in the resulting hierarchical generative model. We trained a deep network with three hidden layers on an artificial dataset of letter strings presented at five possible retinal locations. Though word-level information (i.e., word identity was never provided to the network during training, linear decoding from the activity of the deepest hidden layer yielded near-perfect accuracy in location-invariant word recognition. Conversely, decoding from lower layers yielded a large number of transposition errors. Analyses of emergent internal representations showed that word selectivity and location invariance increased as a function of layer depth. Conversely, there was no evidence for bigram coding. Finally, the distributed internal representation of words at the deepest layer showed higher similarity to the representation elicited by the two exterior letters than by other combinations of two contiguous letters, in agreement with the hypothesis that word edges have special status. These results reveal that the efficient coding of written words – which was the model’s learning objective – is largely based on letter-level information.

  20. Convergent and diagnostic validity of STAVUX, a word and pseudoword spelling test for adults.

    Science.gov (United States)

    Östberg, Per; Backlund, Charlotte; Lindström, Emma

    2016-10-01

    Few comprehensive spelling tests are available in Swedish, and none have been validated in adults with reading and writing disorders. The recently developed STAVUX test includes word and pseudoword spelling subtests with high internal consistency and adult norms stratified by education. This study evaluated the convergent and diagnostic validity of STAVUX in adults with dyslexia. Forty-six adults, 23 with dyslexia and 23 controls, took STAVUX together with a standard word-decoding test and a self-rated measure of spelling skills. STAVUX subtest scores showed moderate to strong correlations with word-decoding scores and predicted self-rated spelling skills. Word and pseudoword subtest scores both predicted dyslexia status. Receiver-operating characteristic (ROC) analysis showed excellent diagnostic discriminability. Sensitivity was 91% and specificity 96%. In conclusion, the results of this study support the convergent and diagnostic validity of STAVUX.

  1. Decoding bipedal locomotion from the rat sensorimotor cortex

    NARCIS (Netherlands)

    Rigosa, J.; Panarese, A.; Dominici, N.; Friedli, L.; van den Brand, R.; Carpaneto, J.; DiGiovanna, J.; Courtine, G.; Micera, S.

    2015-01-01

    Objective. Decoding forelimb movements from the firing activity of cortical neurons has been interfaced with robotic and prosthetic systems to replace lost upper limb functions in humans. Despite the potential of this approach to improve locomotion and facilitate gait rehabilitation, decoding lower

  2. Analysis and Design of Binary Message-Passing Decoders

    DEFF Research Database (Denmark)

    Lechner, Gottfried; Pedersen, Troels; Kramer, Gerhard

    2012-01-01

    Binary message-passing decoders for low-density parity-check (LDPC) codes are studied by using extrinsic information transfer (EXIT) charts. The channel delivers hard or soft decisions and the variable node decoder performs all computations in the L-value domain. A hard decision channel results i...

  3. Illustrative examples in a bilingual decoding dictionary: An (un ...

    African Journals Online (AJOL)

    Abstract: The article discusses the principles underlying the inclusion of illustrative examples in a decoding English–Slovene dictionary. The inclusion of examples in decoding bilingual diction-aries can be justified by taking into account the semantic and grammatical differences between the source and the target languages ...

  4. EXIT Chart Analysis of Binary Message-Passing Decoders

    DEFF Research Database (Denmark)

    Lechner, Gottfried; Pedersen, Troels; Kramer, Gerhard

    2007-01-01

    Binary message-passing decoders for LDPC codes are analyzed using EXIT charts. For the analysis, the variable node decoder performs all computations in the L-value domain. For the special case of a hard decision channel, this leads to the well know Gallager B algorithm, while the analysis can...

  5. Does Linguistic Comprehension Support the Decoding Skills of Struggling Readers?

    Science.gov (United States)

    Blick, Michele; Nicholson, Tom; Chapman, James; Berman, Jeanette

    2017-01-01

    This study investigated the contribution of linguistic comprehension to the decoding skills of struggling readers. Participants were 36 children aged between eight and 12 years, all below average in decoding but differing in linguistic comprehension. The children read passages from the Neale Analysis of Reading Ability and their first 25 miscues…

  6. Interim Manual for the DST: Decoding Skills Test.

    Science.gov (United States)

    Richardson, Ellis; And Others

    The Decoding Skills Test (DST) was developed to provide a detailed measurement of decoding skills which could be used in research on developmental dyslexia. Another purpose of the test is to provide a diagnostic-prescriptive instrument to be used in the evaluation of, and program planning for, children needing remedial reading. The test is…

  7. Illustrative Examples in a Bilingual Decoding Dictionary: An (Un ...

    African Journals Online (AJOL)

    user

    Abstract: The article discusses the principles underlying the inclusion of illustrative examples in a decoding English–Slovene dictionary. The inclusion of examples in decoding bilingual diction- aries can be justified by taking into account the semantic and grammatical differences between the source and the target ...

  8. Decoding suprathreshold stochastic resonance with optimal weights

    International Nuclear Information System (INIS)

    Xu, Liyan; Vladusich, Tony; Duan, Fabing; Gunn, Lachlan J.; Abbott, Derek; McDonnell, Mark D.

    2015-01-01

    We investigate an array of stochastic quantizers for converting an analog input signal into a discrete output in the context of suprathreshold stochastic resonance. A new optimal weighted decoding is considered for different threshold level distributions. We show that for particular noise levels and choices of the threshold levels optimally weighting the quantizer responses provides a reduced mean square error in comparison with the original unweighted array. However, there are also many parameter regions where the original array provides near optimal performance, and when this occurs, it offers a much simpler approach than optimally weighting each quantizer's response. - Highlights: • A weighted summing array of independently noisy binary comparators is investigated. • We present an optimal linearly weighted decoding scheme for combining the comparator responses. • We solve for the optimal weights by applying least squares regression to simulated data. • We find that the MSE distortion of weighting before summation is superior to unweighted summation of comparator responses. • For some parameter regions, the decrease in MSE distortion due to weighting is negligible

  9. Decoding suprathreshold stochastic resonance with optimal weights

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Liyan, E-mail: xuliyan@qdu.edu.cn [Institute of Complexity Science, Qingdao University, Qingdao 266071 (China); Vladusich, Tony [Computational and Theoretical Neuroscience Laboratory, Institute for Telecommunications Research, School of Information Technology and Mathematical Sciences, University of South Australia, SA 5095 (Australia); Duan, Fabing [Institute of Complexity Science, Qingdao University, Qingdao 266071 (China); Gunn, Lachlan J.; Abbott, Derek [Centre for Biomedical Engineering (CBME) and School of Electrical & Electronic Engineering, The University of Adelaide, Adelaide, SA 5005 (Australia); McDonnell, Mark D. [Computational and Theoretical Neuroscience Laboratory, Institute for Telecommunications Research, School of Information Technology and Mathematical Sciences, University of South Australia, SA 5095 (Australia); Centre for Biomedical Engineering (CBME) and School of Electrical & Electronic Engineering, The University of Adelaide, Adelaide, SA 5005 (Australia)

    2015-10-09

    We investigate an array of stochastic quantizers for converting an analog input signal into a discrete output in the context of suprathreshold stochastic resonance. A new optimal weighted decoding is considered for different threshold level distributions. We show that for particular noise levels and choices of the threshold levels optimally weighting the quantizer responses provides a reduced mean square error in comparison with the original unweighted array. However, there are also many parameter regions where the original array provides near optimal performance, and when this occurs, it offers a much simpler approach than optimally weighting each quantizer's response. - Highlights: • A weighted summing array of independently noisy binary comparators is investigated. • We present an optimal linearly weighted decoding scheme for combining the comparator responses. • We solve for the optimal weights by applying least squares regression to simulated data. • We find that the MSE distortion of weighting before summation is superior to unweighted summation of comparator responses. • For some parameter regions, the decrease in MSE distortion due to weighting is negligible.

  10. Unsupervised learning of facial emotion decoding skills

    Directory of Open Access Journals (Sweden)

    Jan Oliver Huelle

    2014-02-01

    Full Text Available Research on the mechanisms underlying human facial emotion recognition has long focussed on genetically determined neural algorithms and often neglected the question of how these algorithms might be tuned by social learning. Here we show that facial emotion decoding skills can be significantly and sustainably improved by practise without an external teaching signal. Participants saw video clips of dynamic facial expressions of five different women and were asked to decide which of four possible emotions (anger, disgust, fear and sadness was shown in each clip. Although no external information about the correctness of the participant’s response or the sender’s true affective state was provided, participants showed a significant increase of facial emotion recognition accuracy both within and across two training sessions two days to several weeks apart. We discuss several similarities and differences between the unsupervised improvement of facial decoding skills observed in the current study, unsupervised perceptual learning of simple stimuli described in previous studies and practise effects often observed in cognitive tasks.

  11. Syllabic Length Effect in Visual Word Recognition

    Directory of Open Access Journals (Sweden)

    Roya Ranjbar Mohammadi

    2014-07-01

    Full Text Available Studies on visual word recognition have resulted in different and sometimes contradictory proposals as Multi-Trace Memory Model (MTM, Dual-Route Cascaded Model (DRC, and Parallel Distribution Processing Model (PDP. The role of the number of syllables in word recognition was examined by the use of five groups of English words and non-words. The reaction time of the participants to these words was measured using reaction time measuring software. The results indicated that there was syllabic effect on recognition of both high and low frequency words. The pattern was incremental in terms of syllable number. This pattern prevailed in high and low frequency words and non-words except in one syllable words. In general, the results are in line with the PDP model which claims that a single processing mechanism is used in both words and non-words recognition. In other words, the findings suggest that lexical items are mainly processed via a lexical route.  A pedagogical implication of the findings would be that reading in English as a foreign language involves analytical processing of the syllable of the words.

  12. The Cognitive Correlates of Third-Grade Skill in Arithmetic, Algorithmic Computation, and Arithmetic Word Problems

    Science.gov (United States)

    Fuchs, Lynn S.; Fuchs, Douglas; Compton, Donald L.; Powell, Sarah R.; Seethaler, Pamela M.; Capizzi, Andrea M.; Schatschneider, Christopher; Fletcher, Jack M.

    2006-01-01

    The purpose of this study was to examine the cognitive correlates of RD-grade skill in arithmetic, algorithmic computation, and arithmetic word problems. Third graders (N = 312) were measured on language, nonverbal problem solving, concept formation, processing speed, long-term memory, working memory, phonological decoding, and sight word…

  13. Phonological and Cognitive Correlates of Word-Reading Acquisition under Two Different Instructional Approaches in Greek.

    Science.gov (United States)

    Papadopoulos, Timothy C.

    2001-01-01

    Examines the relationship between phonological and cognitive tasks with beginning reading acquisition. Uses two teaching techniques for tasks given first-grade students in Cyprus (n=50) and Greece (n=50). Reports differences were revealed in word-decoding accuracy, Greek students showed a higher linguistic ability, and successive processing and…

  14. High Frequency rTMS over the Left Parietal Lobule Increases Non-Word Reading Accuracy

    Science.gov (United States)

    Costanzo, Floriana; Menghini, Deny; Caltagirone, Carlo; Oliveri, Massimiliano; Vicari, Stefano

    2012-01-01

    Increasing evidence in the literature supports the usefulness of Transcranial Magnetic Stimulation (TMS) in studying reading processes. Two brain regions are primarily involved in phonological decoding: the left superior temporal gyrus (STG), which is associated with the auditory representation of spoken words, and the left inferior parietal lobe…

  15. BioWord: A sequence manipulation suite for Microsoft Word

    Directory of Open Access Journals (Sweden)

    Anzaldi Laura J

    2012-06-01

    Full Text Available Abstract Background The ability to manipulate, edit and process DNA and protein sequences has rapidly become a necessary skill for practicing biologists across a wide swath of disciplines. In spite of this, most everyday sequence manipulation tools are distributed across several programs and web servers, sometimes requiring installation and typically involving frequent switching between applications. To address this problem, here we have developed BioWord, a macro-enabled self-installing template for Microsoft Word documents that integrates an extensive suite of DNA and protein sequence manipulation tools. Results BioWord is distributed as a single macro-enabled template that self-installs with a single click. After installation, BioWord will open as a tab in the Office ribbon. Biologists can then easily manipulate DNA and protein sequences using a familiar interface and minimize the need to switch between applications. Beyond simple sequence manipulation, BioWord integrates functionality ranging from dyad search and consensus logos to motif discovery and pair-wise alignment. Written in Visual Basic for Applications (VBA as an open source, object-oriented project, BioWord allows users with varying programming experience to expand and customize the program to better meet their own needs. Conclusions BioWord integrates a powerful set of tools for biological sequence manipulation within a handy, user-friendly tab in a widely used word processing software package. The use of a simple scripting language and an object-oriented scheme facilitates customization by users and provides a very accessible educational platform for introducing students to basic bioinformatics algorithms.

  16. BioWord: a sequence manipulation suite for Microsoft Word.

    Science.gov (United States)

    Anzaldi, Laura J; Muñoz-Fernández, Daniel; Erill, Ivan

    2012-06-07

    The ability to manipulate, edit and process DNA and protein sequences has rapidly become a necessary skill for practicing biologists across a wide swath of disciplines. In spite of this, most everyday sequence manipulation tools are distributed across several programs and web servers, sometimes requiring installation and typically involving frequent switching between applications. To address this problem, here we have developed BioWord, a macro-enabled self-installing template for Microsoft Word documents that integrates an extensive suite of DNA and protein sequence manipulation tools. BioWord is distributed as a single macro-enabled template that self-installs with a single click. After installation, BioWord will open as a tab in the Office ribbon. Biologists can then easily manipulate DNA and protein sequences using a familiar interface and minimize the need to switch between applications. Beyond simple sequence manipulation, BioWord integrates functionality ranging from dyad search and consensus logos to motif discovery and pair-wise alignment. Written in Visual Basic for Applications (VBA) as an open source, object-oriented project, BioWord allows users with varying programming experience to expand and customize the program to better meet their own needs. BioWord integrates a powerful set of tools for biological sequence manipulation within a handy, user-friendly tab in a widely used word processing software package. The use of a simple scripting language and an object-oriented scheme facilitates customization by users and provides a very accessible educational platform for introducing students to basic bioinformatics algorithms.

  17. The Differential Contributions of Auditory-Verbal and Visuospatial Working Memory on Decoding Skills in Children Who Are Poor Decoders

    Science.gov (United States)

    Squires, Katie Ellen

    2013-01-01

    This study investigated the differential contribution of auditory-verbal and visuospatial working memory (WM) on decoding skills in second- and fifth-grade children identified with poor decoding. Thirty-two second-grade students and 22 fifth-grade students completed measures that assessed simple and complex auditory-verbal and visuospatial memory,…

  18. Spatial attention in written word perception

    Directory of Open Access Journals (Sweden)

    Veronica eMontani

    2014-02-01

    Full Text Available The role of attention in visual word recognition and reading aloud is a long debated issue. Studies of both developmental and acquired reading disorders provide growing evidence that spatial attention is critically involved in word reading, in particular for the phonological decoding of unfamiliar letter strings. However, studies on healthy participants have produced contrasting results. The aim of this study was to investigate how the allocation of spatial attention may influence the perception of letter strings in skilled readers. High frequency words, low frequency words and pseudowords were briefly and parafoveally presented either in the left or the right visual field. Attentional allocation was modulated by the presentation of a spatial cue before the target string. Accuracy in reporting the target string was modulated by the spatial cue but this effect varied with the type of string. For unfamiliar strings, processing was facilitated when attention was focused on the string location and hindered when it was diverted from the target. This finding is consistent the assumptions of the CDP+ model of reading aloud, as well as with familiarity sensitivity models that argue for a flexible use of attention according with the specific requirements of the string. Moreover, we found that processing of high-frequency words was facilitated by an extra-large focus of attention. The latter result is consistent with the hypothesis that a broad distribution of attention is the default mode during reading of familiar words because it might optimally engage the broad receptive fields of the highest detectors in the hierarchical system for visual word recognition.

  19. General Purpose Graphics Processing Unit Based High-Rate Rice Decompression and Reed-Solomon Decoding

    Energy Technology Data Exchange (ETDEWEB)

    Loughry, Thomas A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-02-01

    As the volume of data acquired by space-based sensors increases, mission data compression/decompression and forward error correction code processing performance must likewise scale. This competency development effort was explored using the General Purpose Graphics Processing Unit (GPGPU) to accomplish high-rate Rice Decompression and high-rate Reed-Solomon (RS) decoding at the satellite mission ground station. Each algorithm was implemented and benchmarked on a single GPGPU. Distributed processing across one to four GPGPUs was also investigated. The results show that the GPGPU has considerable potential for performing satellite communication Data Signal Processing, with three times or better performance improvements and up to ten times reduction in cost over custom hardware, at least in the case of Rice Decompression and Reed-Solomon Decoding.

  20. Narrative-Based Intervention for Word-Finding Difficulties: A Case Study

    Science.gov (United States)

    Marks, Ian; Stokes, Stephanie F.

    2010-01-01

    Background: Children with word-finding difficulties manifest a high frequency of word-finding characteristics in narrative, yet word-finding interventions have concentrated on single-word treatments and outcome measures. Aims: This study measured the effectiveness of a narrative-based intervention in improving single-word picture-naming and…

  1. Lexical Quality Matters: Effects of Word Knowledge Instruction on the Language and Literacy Skills of Third- and Fourth-Grade Poor Readers

    Science.gov (United States)

    Brinchmann, Ellen Irén; Hjetland, Hanne Naess; Lyster, Solveig-Alma Halaas

    2016-01-01

    The purpose of this study was to explore the hypothesis that teaching students knowledge of word forms and meanings supports the development of decoding and linguistic comprehension, which are fundamental components of reading comprehension. We examined this hypothesis by investigating the effects of a comprehensive word knowledge intervention on…

  2. The Interpretability of the Word “Soxan” in Ferdowsi’s Shahnameh

    Directory of Open Access Journals (Sweden)

    F Vejdani

    2014-02-01

    Foregrounding the status of this word in the linguistic structure of this work which paves the way for the interpretability of the text and also representing his personal style in using such word which asks the reader to decode its meaning and interprets it himself are other aims of this research which is unprecedented among researches about Shahnameh.

  3. Competition between multiple words for a referent in cross-situational word learning

    Science.gov (United States)

    Benitez, Viridiana L.; Yurovsky, Daniel; Smith, Linda B.

    2016-01-01

    Three experiments investigated competition between word-object pairings in a cross-situational word-learning paradigm. Adults were presented with One-Word pairings, where a single word labeled a single object, and Two-Word pairings, where two words labeled a single object. In addition to measuring learning of these two pairing types, we measured competition between words that refer to the same object. When the word-object co-occurrences were presented intermixed in training (Experiment 1), we found evidence for direct competition between words that label the same referent. Separating the two words for an object in time eliminated any evidence for this competition (Experiment 2). Experiment 3 demonstrated that adding a linguistic cue to the second label for a referent led to different competition effects between adults who self-reported different language learning histories, suggesting both distinctiveness and language learning history affect competition. Finally, in all experiments, competition effects were unrelated to participants’ explicit judgments of learning, suggesting that competition reflects the operating characteristics of implicit learning processes. Together, these results demonstrate that the role of competition between overlapping associations in statistical word-referent learning depends on time, the distinctiveness of word-object pairings, and language learning history. PMID:27087742

  4. What's in a Word?

    OpenAIRE

    Henderson, Jennifer A

    2007-01-01

    Words are all around us to the point that their complexity is lost in familiarity. The term “word” itself can ambiguously refer to different linguistic concepts: orthographic words, phonological words, grammatical words, word-forms, lexemes, and to an extent lexical items. While it is hard to come up with exception-less criteria for wordhood, some typical properties are that words are writeable and spellable, consist of morphemes, are syntactic units, carry meaning, and interrelate with oth...

  5. Clinical Strategies for Sampling Word Recognition Performance.

    Science.gov (United States)

    Schlauch, Robert S; Carney, Edward

    2018-03-09

    Computer simulation was used to estimate the statistical properties of searches for maximum word recognition ability (PB max). These involve presenting multiple lists and discarding all scores but that of the 1 list that produced the highest score. The simulations, which model limitations inherent in the precision of word recognition scores, were done to inform clinical protocols. A secondary consideration was a derivation of 95% confidence intervals for significant changes in score from phonemic scoring of a 50-word list. The PB max simulations were conducted on a "client" with flat performance intensity functions. The client's performance was assumed to be 60% initially and 40% for a second assessment. Thousands of estimates were obtained to examine the precision of (a) single lists and (b) multiple lists using a PB max procedure. This method permitted summarizing the precision for assessing a 20% drop in performance. A single 25-word list could identify only 58.4% of the cases in which performance fell from 60% to 40%. A single 125-word list identified 99.8% of the declines correctly. Presenting 3 or 5 lists to find PB max produced an undesirable finding: an increase in the word recognition score. A 25-word list produces unacceptably low precision for making clinical decisions. This finding holds in both single and multiple 25-word lists, as in a search for PB max. A table is provided, giving estimates of 95% critical ranges for successive presentations of a 50-word list analyzed by the number of phonemes correctly identified.

  6. Decoding the mechanisms of Antikythera astronomical device

    CERN Document Server

    Lin, Jian-Liang

    2016-01-01

    This book presents a systematic design methodology for decoding the interior structure of the Antikythera mechanism, an astronomical device from ancient Greece. The historical background, surviving evidence and reconstructions of the mechanism are introduced, and the historical development of astronomical achievements and various astronomical instruments are investigated. Pursuing an approach based on the conceptual design of modern mechanisms and bearing in mind the standards of science and technology at the time, all feasible designs of the six lost/incomplete/unclear subsystems are synthesized as illustrated examples, and 48 feasible designs of the complete interior structure are presented. This approach provides not only a logical tool for applying modern mechanical engineering knowledge to the reconstruction of the Antikythera mechanism, but also an innovative research direction for identifying the original structures of the mechanism in the future. In short, the book offers valuable new insights for all...

  7. Academic Training - Bioinformatics: Decoding the Genome

    CERN Multimedia

    Chris Jones

    2006-01-01

    ACADEMIC TRAINING LECTURE SERIES 27, 28 February 1, 2, 3 March 2006 from 11:00 to 12:00 - Auditorium, bldg. 500 Decoding the Genome A special series of 5 lectures on: Recent extraordinary advances in the life sciences arising through new detection technologies and bioinformatics The past five years have seen an extraordinary change in the information and tools available in the life sciences. The sequencing of the human genome, the discovery that we possess far fewer genes than foreseen, the measurement of the tiny changes in the genomes that differentiate us, the sequencing of the genomes of many pathogens that lead to diseases such as malaria are all examples of completely new information that is now available in the quest for improved healthcare. New tools have allowed similar strides in the discovery of the associated protein structures, providing invaluable information for those searching for new drugs. New DNA microarray chips permit simultaneous measurement of the state of expression of tens...

  8. O2-GIDNC: Beyond instantly decodable network coding

    KAUST Repository

    Aboutorab, Neda

    2013-06-01

    In this paper, we are concerned with extending the graph representation of generalized instantly decodable network coding (GIDNC) to a more general opportunistic network coding (ONC) scenario, referred to as order-2 GIDNC (O2-GIDNC). In the O2-GIDNC scheme, receivers can store non-instantly decodable packets (NIDPs) comprising two of their missing packets, and use them in a systematic way for later decodings. Once this graph representation is found, it can be used to extend the GIDNC graph-based analyses to the proposed O2-GIDNC scheme with a limited increase in complexity. In the proposed O2-GIDNC scheme, the information of the stored NIDPs at the receivers and the decoding opportunities they create can be exploited to improve the broadcast completion time and decoding delay compared to traditional GIDNC scheme. The completion time and decoding delay minimizing algorithms that can operate on the new O2-GIDNC graph are further described. The simulation results show that our proposed O2-GIDNC improves the completion time and decoding delay performance of the traditional GIDNC. © 2013 IEEE.

  9. Encoder-decoder optimization for brain-computer interfaces.

    Directory of Open Access Journals (Sweden)

    Josh Merel

    2015-06-01

    Full Text Available Neuroprosthetic brain-computer interfaces are systems that decode neural activity into useful control signals for effectors, such as a cursor on a computer screen. It has long been recognized that both the user and decoding system can adapt to increase the accuracy of the end effector. Co-adaptation is the process whereby a user learns to control the system in conjunction with the decoder adapting to learn the user's neural patterns. We provide a mathematical framework for co-adaptation and relate co-adaptation to the joint optimization of the user's control scheme ("encoding model" and the decoding algorithm's parameters. When the assumptions of that framework are respected, co-adaptation cannot yield better performance than that obtainable by an optimal initial choice of fixed decoder, coupled with optimal user learning. For a specific case, we provide numerical methods to obtain such an optimized decoder. We demonstrate our approach in a model brain-computer interface system using an online prosthesis simulator, a simple human-in-the-loop pyschophysics setup which provides a non-invasive simulation of the BCI setting. These experiments support two claims: that users can learn encoders matched to fixed, optimal decoders and that, once learned, our approach yields expected performance advantages.

  10. Learning Word Sense Embeddings from Word Sense Definitions

    OpenAIRE

    Li, Qi; Li, Tianshi; Chang, Baobao

    2016-01-01

    Word embeddings play a significant role in many modern NLP systems. Since learning one representation per word is problematic for polysemous words and homonymous words, researchers propose to use one embedding per word sense. Their approaches mainly train word sense embeddings on a corpus. In this paper, we propose to use word sense definitions to learn one embedding per word sense. Experimental results on word similarity tasks and a word sense disambiguation task show that word sense embeddi...

  11. Turbo decoder architecture for beyond-4G applications

    CERN Document Server

    Wong, Cheng-Chi

    2013-01-01

    This book describes the most recent techniques for turbo decoder implementation, especially for 4G and beyond 4G applications. The authors reveal techniques for the design of high-throughput decoders for future telecommunication systems, enabling designers to reduce hardware cost and shorten processing time. Coverage includes an explanation of VLSI implementation of the turbo decoder, from basic functional units to advanced parallel architecture. The authors discuss both hardware architecture techniques and experimental results, showing the variations in area/throughput/performance with respec

  12. Spatial attention in written word perception.

    Science.gov (United States)

    Montani, Veronica; Facoetti, Andrea; Zorzi, Marco

    2014-01-01

    The role of attention in visual word recognition and reading aloud is a long debated issue. Studies of both developmental and acquired reading disorders provide growing evidence that spatial attention is critically involved in word reading, in particular for the phonological decoding of unfamiliar letter strings. However, studies on healthy participants have produced contrasting results. The aim of this study was to investigate how the allocation of spatial attention may influence the perception of letter strings in skilled readers. High frequency words (HFWs), low frequency words and pseudowords were briefly and parafoveally presented either in the left or the right visual field. Attentional allocation was modulated by the presentation of a spatial cue before the target string. Accuracy in reporting the target string was modulated by the spatial cue but this effect varied with the type of string. For unfamiliar strings, processing was facilitated when attention was focused on the string location and hindered when it was diverted from the target. This finding is consistent the assumptions of the CDP+ model of reading aloud, as well as with familiarity sensitivity models that argue for a flexible use of attention according with the specific requirements of the string. Moreover, we found that processing of HFWs was facilitated by an extra-large focus of attention. The latter result is consistent with the hypothesis that a broad distribution of attention is the default mode during reading of familiar words because it might optimally engage the broad receptive fields of the highest detectors in the hierarchical system for visual word recognition.

  13. Knowledge inhibition and N400: a study with words that look like common words.

    Science.gov (United States)

    Debruille, J B

    1998-04-01

    In addition to their own representations, low frequency words, such as BRIBE, can covertly activate the representations of higher frequency words they look like (e.g., BRIDE). Hence, look-alike words can activate knowledge that is incompatible with the knowledge corresponding to accurate representations. Comparatively, eccentric words, that is, low frequency words that do not look as much like higher frequency words, are less likely to activate incompatible knowledge. This study focuses on the hypothesis that the N400 component of the event-related potential reflects the inhibition of incompatible knowledge. This hypothesis predicts that look-alike words elicit N400s of greater amplitudes than eccentric words in conditions where incompatible knowledge is inhibited. Results from a single item lexical decision experiment are reported which support the inhibition hypothesis. Copyright 1998 Academic Press.

  14. Don’t words come easy?A psychophysical exploration of word superiority

    Directory of Open Access Journals (Sweden)

    Randi eStarrfelt

    2013-09-01

    Full Text Available Words are made of letters, and yet sometimes it is easier to identify a word than a single letter. This word superiority effect (WSE has been observed when written stimuli are presented very briefly or degraded by visual noise. We compare performance with letters and words in three experiments, to explore the extents and limits of the WSE. Using a carefully controlled list of three letter words, we show that a word superiority effect can be revealed in vocal reaction times even to undegraded stimuli. With a novel combination of psychophysics and mathematical modelling, we further show that the typical WSE is specifically reflected in perceptual processing speed: single words are simply processed faster than single letters. Intriguingly, when multiple stimuli are presented simultaneously, letters are perceived more easily than words, and this is reflected both in perceptual processing speed and visual short term memory capacity. So, even if single words come easy, there is a limit to the word superiority effect.

  15. Growth of Word and Pseudoword Reading Efficiency in Alphabetic Orthographies: Impact of Consistency.

    Science.gov (United States)

    Caravolas, Markéta

    2017-07-01

    Word and pseudoword reading are related abilities fundamental to reading development in alphabetic orthographies. They are respectively assumed to index children's orthographic representations of words, which are in turn acquired through the underlying "self-teaching mechanism" of alphabetic pseudoword decoding. Little is known about concurrent growth trajectories of these skills in the early grades among children learning different alphabetic orthographies. In the present study, between- and within-group latent growth models of word and pseudoword reading efficiency were tested on data spanning Grades 1 and 2 from learners of the inconsistent English and consistent Czech and Slovak orthographies. Several language-general patterns emerged. Significant growth was observed for both skills in all languages. Growth was faster for word than pseudoword reading efficiency, and strong lexicality effects that increased over time were obtained across languages. Language-specific patterns were also found. In line with predictions about the costs of learning lower-consistency orthographies, readers of English experienced relatively slower growth on both reading skills. However, their lag was smaller, and evident only at the latter two time points for word reading. In contrast, on pseudoword reading, the English group performed considerably less well than their Czech and Slovak peers at every time point. Thus, weaker decoding skills were the main contributor to the larger lexicality effects of the English group. These findings are considered within the frame of recent theorizing about the effect of orthographic consistency on decoding as a self-teaching mechanism in alphabetic reading acquisition.

  16. Learning from Decoding across Disciplines and within Communities of Practice

    Science.gov (United States)

    Miller-Young, Janice; Boman, Jennifer

    2017-01-01

    This final chapter synthesizes the findings and implications derived from applying the Decoding the Disciplines model across disciplines and within communities of practice. We make practical suggestions for teachers and researchers who wish to apply and extend this work.

  17. Can words be read without abstract letter identities?

    Directory of Open Access Journals (Sweden)

    Simon Fischer-Baum

    2014-04-01

    CH’s acquired dyslexia and dysgraphia left him with a profound impairment in processing abstract letter identities. This impairment affected his ability to process strings of letters in a variety of tasks; for example nonword reading, spelling, recognizing orally spelled words. However, while impaired, his single word reading was surprisingly good given his single letter impairment, suggesting an additional route to word meaning from visually-presented familiar words that does not require abstract letter identities.

  18. Effect of video decoder errors on video interpretability

    Science.gov (United States)

    Young, Darrell L.

    2014-06-01

    The advancement in video compression technology can result in more sensitivity to bit errors. Bit errors can propagate causing sustained loss of interpretability. In the worst case, the decoder "freezes" until it can re-synchronize with the stream. Detection of artifacts enables downstream processes to avoid corrupted frames. A simple template approach to detect block stripes and a more advanced cascade approach to detect compression artifacts was shown to correlate to the presence of artifacts and decoder messages.

  19. Decoding of finger trajectory from ECoG using Deep Learning.

    Science.gov (United States)

    Xie, Ziqian; Schwartz, Odelia; Prasad, Abhishek

    2017-11-28

    Conventional decoding pipeline for brain machine interfaces (BMIs) consists of chained different stages of feature extraction, time-frequency analysis and statistical learning models. Each of these stages uses a different algorithm trained in a sequential manner, which makes it difficult to make the whole system adaptive. The goal was to create an adaptive online system with a single objective function and a single learning algorithm so that the whole system can be trained in parallel to increase the decoding performance. Here, we used deep neural networks consisting of convolutional neural networks (CNN) and a special kind of recurrent neural network (RNN) called long short term memory (LSTM) to address these needs. Approach: We used electrocorticography (ECoG) data collected by Kubanek et al. The task consisted of individual finger flexions upon a visual cue. Our model combined a hierarchical feature extractor CNN and a RNN that was able to process sequential data and recognize temporal dynamics in the neural data. CNN was used as the feature extractor and LSTM was used as the regression algorithm to capture the temporal dynamics of the signal. Results: We predicted the finger trajectory using ECoG signals and compared results for the least angle regression (LARS), CNN-LSTM, Random Forest, LSTM model (LSTM_HC, for using hard-coded features) and a decoding pipeline consisting of band-pass filtering, energy extraction, feature selection and linear regression. The results showed that the deep learning models performed better than the commonly used linear model. The deep learning models not only gave smoother and more realistic trajectories but also learned the transition between movement and rest state. Significance: This study demonstrated a decoding network for BMI that involved a convolutional and recurrent neural network model. It integrated the feature extraction pipeline into the convolution and pooling layer and used LSTM layer to capture the

  20. The brain's silent messenger: using selective attention to decode human thought for brain-based communication.

    Science.gov (United States)

    Naci, Lorina; Cusack, Rhodri; Jia, Vivian Z; Owen, Adrian M

    2013-05-29

    The interpretation of human thought from brain activity, without recourse to speech or action, is one of the most provoking and challenging frontiers of modern neuroscience. In particular, patients who are fully conscious and awake, yet, due to brain damage, are unable to show any behavioral responsivity, expose the limits of the neuromuscular system and the necessity for alternate forms of communication. Although it is well established that selective attention can significantly enhance the neural representation of attended sounds, it remains, thus far, untested as a response modality for brain-based communication. We asked whether its effect could be reliably used to decode answers to binary (yes/no) questions. Fifteen healthy volunteers answered questions (e.g., "Do you have brothers or sisters?") in the fMRI scanner, by selectively attending to the appropriate word ("yes" or "no"). Ninety percent of the answers were decoded correctly based on activity changes within the attention network. The majority of volunteers conveyed their answers with less than 3 min of scanning, suggesting that this technique is suited for communication in a reasonable amount of time. Formal comparison with the current best-established fMRI technique for binary communication revealed improved individual success rates and scanning times required to detect responses. This novel fMRI technique is intuitive, easy to use in untrained participants, and reliably robust within brief scanning times. Possible applications include communication with behaviorally nonresponsive patients.

  1. Partially blind instantly decodable network codes for lossy feedback environment

    KAUST Repository

    Sorour, Sameh

    2014-09-01

    In this paper, we study the multicast completion and decoding delay minimization problems for instantly decodable network coding (IDNC) in the case of lossy feedback. When feedback loss events occur, the sender falls into uncertainties about packet reception at the different receivers, which forces it to perform partially blind selections of packet combinations in subsequent transmissions. To determine efficient selection policies that reduce the completion and decoding delays of IDNC in such an environment, we first extend the perfect feedback formulation in our previous works to the lossy feedback environment, by incorporating the uncertainties resulting from unheard feedback events in these formulations. For the completion delay problem, we use this formulation to identify the maximum likelihood state of the network in events of unheard feedback and employ it to design a partially blind graph update extension to the multicast IDNC algorithm in our earlier work. For the decoding delay problem, we derive an expression for the expected decoding delay increment for any arbitrary transmission. This expression is then used to find the optimal policy that reduces the decoding delay in such lossy feedback environment. Results show that our proposed solutions both outperform previously proposed approaches and achieve tolerable degradation even at relatively high feedback loss rates.

  2. Evaluation framework for K-best sphere decoders

    KAUST Repository

    Shen, Chungan

    2010-08-01

    While Maximum-Likelihood (ML) is the optimum decoding scheme for most communication scenarios, practical implementation difficulties limit its use, especially for Multiple Input Multiple Output (MIMO) systems with a large number of transmit or receive antennas. Tree-searching type decoder structures such as Sphere decoder and K-best decoder present an interesting trade-off between complexity and performance. Many algorithmic developments and VLSI implementations have been reported in literature with widely varying performance to area and power metrics. In this semi-tutorial paper we present a holistic view of different Sphere decoding techniques and K-best decoding techniques, identifying the key algorithmic and implementation trade-offs. We establish a consistent benchmark framework to investigate and compare the delay cost, power cost, and power-delay-product cost incurred by each method. Finally, using the framework, we propose and analyze a novel architecture and compare that to other published approaches. Our goal is to explicitly elucidate the overall advantages and disadvantages of each proposed algorithms in one coherent framework. © 2010 World Scientific Publishing Company.

  3. Constraint-based Word Segmentation for Chinese

    DEFF Research Database (Denmark)

    Christiansen, Henning; Bo, Li

    2014-01-01

    Written Chinese text has no separators between words in the same way as European languages use space characters, and this creates the Chinese Word Segmentation Problem, CWSP: given a text in Chinese, divide it in a correct way into segments corresponding to words. Good solutions are in demand...... for virtually any nontrivial computational processing of Chinese text, ranging from spellchecking over internet search to deep analysis. Isolating the single words is usually the first phase in the analysis of a text, but as for many other language analysis tasks, to do that perfectly, an insight in syntactic...

  4. Designing and measuring the impact of using digital learning materials for scaffolding students’ independent decoding and comprehension of unfamiliar texts

    DEFF Research Database (Denmark)

    Gissel, Stig Toke

    In a design-based research project the aim was to design and measure the impact of using digital learning materials that scaffold Danish second graders’ independent reading of unfamiliar text without controlled vocabulary. In the design process a prototype was evaluated and refined iteratively...... students in identifying the most relevant spelling patterns in words they cannot decode independently or effortlessly. In the formative evaluations, students’ interaction with the learning material was recorded using screen recording software. The effect of students using the learning material was measured...

  5. Direct migration motion estimation and mode decision to decoder for a low-complexity decoder Wyner-Ziv video coding

    Science.gov (United States)

    Lei, Ted Chih-Wei; Tseng, Fan-Shuo

    2017-07-01

    This paper addresses the problem of high-computational complexity decoding in traditional Wyner-Ziv video coding (WZVC). The key focus is the migration of two traditionally high-computationally complex encoder algorithms, namely motion estimation and mode decision. In order to reduce the computational burden in this process, the proposed architecture adopts the partial boundary matching algorithm and four flexible types of block mode decision at the decoder. This approach does away with the need for motion estimation and mode decision at the encoder. The experimental results show that the proposed padding block-based WZVC not only decreases decoder complexity to approximately one hundredth that of the state-of-the-art DISCOVER decoding but also outperforms DISCOVER codec by up to 3 to 4 dB.

  6. Decoding P4-ATPase substrate interactions.

    Science.gov (United States)

    Roland, Bartholomew P; Graham, Todd R

    Cellular membranes display a diversity of functions that are conferred by the unique composition and organization of their proteins and lipids. One important aspect of lipid organization is the asymmetric distribution of phospholipids (PLs) across the plasma membrane. The unequal distribution of key PLs between the cytofacial and exofacial leaflets of the bilayer creates physical surface tension that can be used to bend the membrane; and like Ca 2+ , a chemical gradient that can be used to transduce biochemical signals. PL flippases in the type IV P-type ATPase (P4-ATPase) family are the principle transporters used to set and repair this PL gradient and the asymmetric organization of these membranes are encoded by the substrate specificity of these enzymes. Thus, understanding the mechanisms of P4-ATPase substrate specificity will help reveal their role in membrane organization and cell biology. Further, decoding the structural determinants of substrate specificity provides investigators the opportunity to mutationally tune this specificity to explore the role of particular PL substrates in P4-ATPase cellular functions. This work reviews the role of P4-ATPases in membrane biology, presents our current understanding of P4-ATPase substrate specificity, and discusses how these fundamental aspects of P4-ATPase enzymology may be used to enhance our knowledge of cellular membrane biology.

  7. Rate Aware Instantly Decodable Network Codes

    KAUST Repository

    Douik, Ahmed

    2016-02-26

    This paper addresses the problem of reducing the delivery time of data messages to cellular users using instantly decodable network coding (IDNC) with physical-layer rate awareness. While most of the existing literature on IDNC does not consider any physical layer complications, this paper proposes a cross-layer scheme that incorporates the different channel rates of the various users in the decision process of both the transmitted message combinations and the rates with which they are transmitted. The completion time minimization problem in such scenario is first shown to be intractable. The problem is, thus, approximated by reducing, at each transmission, the increase of an anticipated version of the completion time. The paper solves the problem by formulating it as a maximum weight clique problem over a newly designed rate aware IDNC (RA-IDNC) graph. Further, the paper provides a multi-layer solution to improve the completion time approximation. Simulation results suggest that the cross-layer design largely outperforms the uncoded transmissions strategies and the classical IDNC scheme. © 2015 IEEE.

  8. Decoding reality the universe as quantum information

    CERN Document Server

    Vedral, Vlatko

    2010-01-01

    In Decoding Reality, Vlatko Vedral offers a mind-stretching look at the deepest questions about the universe--where everything comes from, why things are as they are, what everything is. The most fundamental definition of reality is not matter or energy, he writes, but information--and it is the processing of information that lies at the root of all physical, biological, economic, and social phenomena. This view allows Vedral to address a host of seemingly unrelated questions: Why does DNA bind like it does? What is the ideal diet for longevity? How do you make your first million dollars? We can unify all through the understanding that everything consists of bits of information, he writes, though that raises the question of where these bits come from. To find the answer, he takes us on a guided tour through the bizarre realm of quantum physics. At this sub-sub-subatomic level, we find such things as the interaction of separated quantum particles--what Einstein called "spooky action at a distance." In fact, V...

  9. DECODING OF STRUCTURALLY AND LOGICAL CODES

    Directory of Open Access Journals (Sweden)

    Yu. D. Ivanov

    2016-01-01

    Full Text Available The article deals with the description of the main points of the structural and logical coding and the features of SLC codes. There are shown the basic points of the generalized algorithm of decoding SLC, which is based on the method of perfect matrix arrangement (PMA of the n-dimensional cube vertices for adequate representation and transformation of boolean functions, which is based on the method of generating sequences of variables for building the maximum coverage of the cube vertices. The structural and logical codes (SLC use natural logic redundancy of the infimum disjunctive normal forms (IDNF of boolean functions, which make the basis for building the SLC codes and correcting the errors, that occur during data transfer in real discrete channels, on the channels with independent errors. The main task is to define the basic relations between the implemented SLC codes of the logical redundancy and boundary values of multiplicity of independent errors which are corrected. The principal difference between the SLC codes and the well-known correcting codes is that the redundancy, that is needed to correct the errors in converting the discrete information, is not introduced into an additional code sequence but is defined in a natural way, during the construction of codewords of SLC.

  10. Word 2013 for dummies

    CERN Document Server

    Gookin, Dan

    2013-01-01

    This bestselling guide to Microsoft Word is the first and last word on Word 2013 It's a whole new Word, so jump right into this book and learn how to make the most of it. Bestselling For Dummies author Dan Gookin puts his usual fun and friendly candor back to work to show you how to navigate the new features of Word 2013. Completely in tune with the needs of the beginning user, Gookin explains how to use Word 2013 quickly and efficiently so that you can spend more time working on your projects and less time trying to figure it all out. Walks you through the capabilit

  11. Decoding 3-D reach and grasp kinematics from high-frequency local field potentials in primate primary motor cortex.

    Science.gov (United States)

    Zhuang, Jun; Truccolo, Wilson; Vargas-Irwin, Carlos; Donoghue, John P

    2010-07-01

    Intracortical microelectrode array recordings generate a variety of neural signals with potential application as control signals in neural interface systems. Previous studies have focused on single and multiunit activity (MUA), as well as low-frequency local field potentials (LFPs), but have not explored higher frequency (>200 Hz) LFPs. In addition, the potential to decode 3-D reach and grasp kinematics based on LFPs has not been demonstrated. Here, we use mutual information and decoding analyses to probe the information content about 3-D reaching and grasping of seven different LFP frequency bands in the range of 0.3-400 Hz. LFPs were recorded via 96-microelectrode arrays in primary motor cortex (M1) of two monkeys performing free reaching to grasp moving objects. Mutual information analyses revealed that higher frequency bands (e.g., 100-200 and 200-400 Hz) carried the most information about the examined kinematics. Furthermore, Kalman filter decoding revealed that broad-band high frequency LFPs, likely reflecting MUA, provided the best decoding performance as well as substantial accuracy in reconstructing reach kinematics, grasp aperture, and aperture velocity. These results indicate that LFPs, especially high frequency bands, could be useful signals for neural interfaces controlling 3-D reach and grasp kinematics.

  12. Combinatorics on words Christoffel words and repetitions in words

    CERN Document Server

    Berstel, Jean; Reutenauer, Christophe; Saliola, Franco V

    2008-01-01

    The two parts of this text are based on two series of lectures delivered by Jean Berstel and Christophe Reutenauer in March 2007 at the Centre de Recherches Mathématiques, Montréal, Canada. Part I represents the first modern and comprehensive exposition of the theory of Christoffel words. Part II presents numerous combinatorial and algorithmic aspects of repetition-free words stemming from the work of Axel Thue-a pioneer in the theory of combinatorics on words. A beginner to the theory of combinatorics on words will be motivated by the numerous examples, and the large variety of exercises, which make the book unique at this level of exposition. The clean and streamlined exposition and the extensive bibliography will also be appreciated. After reading this book, beginners should be ready to read modern research papers in this rapidly growing field and contribute their own research to its development. Experienced readers will be interested in the finitary approach to Sturmian words that Christoffel words offe...

  13. Phoneme awareness, vocabulary and word decoding in monolingual and bilingual Dutch children

    NARCIS (Netherlands)

    Janssen, M.; Bosman, A.M.T.; Leseman, P.P.M.

    2013-01-01

    The aim of this study was to investigate whether bilingually raised children in the Netherlands, who receive literacy instruction in their second language only, show an advantage on Dutch phoneme-awareness tasks compared with monolingual Dutch-speaking children. Language performance of a group of 47

  14. Toddlers' sensitivity to within-word coarticulation during spoken word recognition: Developmental differences in lexical competition.

    Science.gov (United States)

    Zamuner, Tania S; Moore, Charlotte; Desmeules-Trudel, Félix

    2016-12-01

    To understand speech, listeners need to be able to decode the speech stream into meaningful units. However, coarticulation causes phonemes to differ based on their context. Because coarticulation is an ever-present component of the speech stream, it follows that listeners may exploit this source of information for cues to the identity of the words being spoken. This research investigates the development of listeners' sensitivity to coarticulation cues below the level of the phoneme in spoken word recognition. Using a looking-while-listening paradigm, adults and 2- and 3-year-old children were tested on coarticulation cues that either matched or mismatched the target. Both adults and children predicted upcoming phonemes based on anticipatory coarticulation to make decisions about word identity. The overall results demonstrate that coarticulation cues are a fundamental component of children's spoken word recognition system. However, children did not show the same resolution as adults of the mismatching coarticulation cues and competitor inhibition, indicating that children's processing systems are still developing. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Singer product apertures—A coded aperture system with a fast decoding algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Byard, Kevin, E-mail: kevin.byard@aut.ac.nz [School of Economics, Faculty of Business, Economics and Law, Auckland University of Technology, Auckland 1142 (New Zealand); Shutler, Paul M.E. [National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616 (Singapore)

    2017-06-01

    A new type of coded aperture configuration that enables fast decoding of the coded aperture shadowgram data is presented. Based on the products of incidence vectors generated from the Singer difference sets, we call these Singer product apertures. For a range of aperture dimensions, we compare experimentally the performance of three decoding methods: standard decoding, induction decoding and direct vector decoding. In all cases the induction and direct vector methods are several orders of magnitude faster than the standard method, with direct vector decoding being significantly faster than induction decoding. For apertures of the same dimensions the increase in speed offered by direct vector decoding over induction decoding is better for lower throughput apertures.

  16. Singer product apertures—A coded aperture system with a fast decoding algorithm

    International Nuclear Information System (INIS)

    Byard, Kevin; Shutler, Paul M.E.

    2017-01-01

    A new type of coded aperture configuration that enables fast decoding of the coded aperture shadowgram data is presented. Based on the products of incidence vectors generated from the Singer difference sets, we call these Singer product apertures. For a range of aperture dimensions, we compare experimentally the performance of three decoding methods: standard decoding, induction decoding and direct vector decoding. In all cases the induction and direct vector methods are several orders of magnitude faster than the standard method, with direct vector decoding being significantly faster than induction decoding. For apertures of the same dimensions the increase in speed offered by direct vector decoding over induction decoding is better for lower throughput apertures.

  17. Neuroimaging of decoding and language comprehension in young very low birth weight (VLBW adolescents: Indications for compensatory mechanisms.

    Directory of Open Access Journals (Sweden)

    Helene van Ettinger-Veenstra

    Full Text Available In preterm children with very low birth weight (VLBW ≤ 1500 g, reading problems are often observed. Reading comprehension is dependent on word decoding and language comprehension. We investigated neural activation-within brain regions important for reading-related to components of reading comprehension in young VLBW adolescents in direct comparison to normal birth weight (NBW term-born peers, with the use of functional magnetic resonance imaging (fMRI. We hypothesized that the decoding mechanisms will be affected by VLBW, and expect to see increased neural activity for VLBW which may be modulated by task performance and cognitive ability. The study investigated 13 (11 included in fMRI young adolescents (ages 12 to 14 years born preterm with VLBW and in 13 NBW controls (ages 12-14 years for performance on the Block Design and Vocabulary subtests of the Wechsler Intelligence Scale for Children; and for semantic, orthographic, and phonological processing during an fMRI paradigm. The VLBW group showed increased phonological activation in left inferior frontal gyrus, decreased orthographic activation in right supramarginal gyrus, and decreased semantic activation in left inferior frontal gyrus. Block Design was related to altered right-hemispheric activation, and VLBW showed lower WISC Block Design scores. Left angular gyrus showed activation increase specific for VLBW with high accuracy on the semantic test. Young VLBW adolescents showed no accuracy and reaction time performance differences on our fMRI language tasks, but they did exhibit altered neural activation during these tasks. This altered activation for VLBW was observed as increased activation during phonological decoding, and as mainly decreased activation during orthographic and semantic processing. Correlations of neural activation with accuracy on the semantic fMRI task and with decreased WISC Block Design performance were specific for the VLBW group. Together, results suggest

  18. Learning to associate orientation with color in early visual areas by associative decoded fMRI neurofeedback

    OpenAIRE

    Amano, Kaoru; Shibata, Kazuhisa; Kawato, Mitsuo; Sasaki, Yuka; Watanabe, Takeo

    2016-01-01

    Associative learning is an essential brain process where the contingency of different items increases after training. Associative learning has been found to occur in many brain regions [1-4]. However, there is no clear evidence that associative learning of visual features occurs in early visual areas, although a number of studies have indicated that learning of a single visual feature (perceptual learning) involves early visual areas [5-8]. Here, via decoded functional magnetic resonance imag...

  19. WordPress Bible

    CERN Document Server

    Brazell, Aaron

    2010-01-01

    The WordPress Bible provides a complete and thorough guide to the largest self hosted blogging tool. This guide starts by covering the basics of WordPress such as installing and the principles of blogging, marketing and social media interaction, but then quickly ramps the reader up to more intermediate to advanced level topics such as plugins, WordPress Loop, themes and templates, custom fields, caching, security and more. The WordPress Bible is the only complete resource one needs to learning WordPress from beginning to end.

  20. Morphological Influences on the Recognition of Monosyllabic Monomorphemic Words

    Science.gov (United States)

    Baayen, R. H.; Feldman, L. B.; Schreuder, R.

    2006-01-01

    Balota et al. [Balota, D., Cortese, M., Sergent-Marshall, S., Spieler, D., & Yap, M. (2004). Visual word recognition for single-syllable words. "Journal of Experimental Psychology: General, 133," 283-316] studied lexical processing in word naming and lexical decision using hierarchical multiple regression techniques for a large data set of…

  1. Novel word acquisition in aphasia: Facing the word-referent ambiguity of natural language learning contexts.

    Science.gov (United States)

    Peñaloza, Claudia; Mirman, Daniel; Tuomiranta, Leena; Benetello, Annalisa; Heikius, Ida-Maria; Järvinen, Sonja; Majos, Maria C; Cardona, Pedro; Juncadella, Montserrat; Laine, Matti; Martin, Nadine; Rodríguez-Fornells, Antoni

    2016-06-01

    Recent research suggests that some people with aphasia preserve some ability to learn novel words and to retain them in the long-term. However, this novel word learning ability has been studied only in the context of single word-picture pairings. We examined the ability of people with chronic aphasia to learn novel words using a paradigm that presents new word forms together with a limited set of different possible visual referents and requires the identification of the correct word-object associations on the basis of online feedback. We also studied the relationship between word learning ability and aphasia severity, word processing abilities, and verbal short-term memory (STM). We further examined the influence of gross lesion location on new word learning. The word learning task was first validated with a group of forty-five young adults. Fourteen participants with chronic aphasia were administered the task and underwent tests of immediate and long-term recognition memory at 1 week. Their performance was compared to that of a group of fourteen matched controls using growth curve analysis. The learning curve and recognition performance of the aphasia group was significantly below the matched control group, although above-chance recognition performance and case-by-case analyses indicated that some participants with aphasia had learned the correct word-referent mappings. Verbal STM but not word processing abilities predicted word learning ability after controlling for aphasia severity. Importantly, participants with lesions in the left frontal cortex performed significantly worse than participants with lesions that spared the left frontal region both during word learning and on the recognition tests. Our findings indicate that some people with aphasia can preserve the ability to learn a small novel lexicon in an ambiguous word-referent context. This learning and recognition memory ability was associated with verbal STM capacity, aphasia severity and the integrity

  2. Word and object recognition during reading acquisition: MEG evidence.

    Science.gov (United States)

    Caffarra, Sendy; Martin, Clara D; Lizarazu, Mikel; Lallier, Marie; Zarraga, Asier; Molinaro, Nicola; Carreiras, Manuel

    2017-04-01

    Studies on adults suggest that reading-induced brain changes might not be limited to linguistic processes. It is still unclear whether these results can be generalized to reading development. The present study shows to which extent neural responses to verbal and nonverbal stimuli are reorganized while children learn to read. MEG data of thirty Basque children (4-8y) were collected while they were presented with written words, spoken words and visual objects. The evoked fields elicited by the experimental stimuli were compared to their scrambled counterparts. Visual words elicited left posterior (200-300ms) and temporal activations (400-800ms). The size of these effects increased as reading performance improved, suggesting a reorganization of children's visual word responses. Spoken words elicited greater left temporal responses relative to scrambles (300-700ms). No evidence for the influence of reading expertise was observed. Brain responses to objects were greater than to scrambles in bilateral posterior regions (200-500ms). There was a greater left hemisphere involvement as reading errors decreased, suggesting a strengthened verbal decoding of visual configurations with reading acquisition. The present results reveal that learning to read not only influences written word processing, but also affects visual object recognition, suggesting a non-language specific impact of reading on children's neural mechanisms. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Word and object recognition during reading acquisition: MEG evidence

    Directory of Open Access Journals (Sweden)

    Sendy Caffarra

    2017-04-01

    Full Text Available Studies on adults suggest that reading-induced brain changes might not be limited to linguistic processes. It is still unclear whether these results can be generalized to reading development. The present study shows to which extent neural responses to verbal and nonverbal stimuli are reorganized while children learn to read. MEG data of thirty Basque children (4–8y were collected while they were presented with written words, spoken words and visual objects. The evoked fields elicited by the experimental stimuli were compared to their scrambled counterparts. Visual words elicited left posterior (200–300 ms and temporal activations (400–800 ms. The size of these effects increased as reading performance improved, suggesting a reorganization of children’s visual word responses. Spoken words elicited greater left temporal responses relative to scrambles (300–700 ms. No evidence for the influence of reading expertise was observed. Brain responses to objects were greater than to scrambles in bilateral posterior regions (200–500 ms. There was a greater left hemisphere involvement as reading errors decreased, suggesting a strengthened verbal decoding of visual configurations with reading acquisition. The present results reveal that learning to read not only influences written word processing, but also affects visual object recognition, suggesting a non-language specific impact of reading on children’s neural mechanisms.

  4. Decoding post-stroke motor function from structural brain imaging

    Directory of Open Access Journals (Sweden)

    Jane M. Rondina

    2016-01-01

    Full Text Available Clinical research based on neuroimaging data has benefited from machine learning methods, which have the ability to provide individualized predictions and to account for the interaction among units of information in the brain. Application of machine learning in structural imaging to investigate diseases that involve brain injury presents an additional challenge, especially in conditions like stroke, due to the high variability across patients regarding characteristics of the lesions. Extracting data from anatomical images in a way that translates brain damage information into features to be used as input to learning algorithms is still an open question. One of the most common approaches to capture regional information from brain injury is to obtain the lesion load per region (i.e. the proportion of voxels in anatomical structures that are considered to be damaged. However, no systematic evaluation has yet been performed to compare this approach with using patterns of voxels (i.e. considering each voxel as a single feature. In this paper we compared both approaches applying Gaussian Process Regression to decode motor scores in 50 chronic stroke patients based solely on data derived from structural MRI. For both approaches we compared different ways to delimit anatomical areas: regions of interest from an anatomical atlas, the corticospinal tract, a mask obtained from fMRI analysis with a motor task in healthy controls and regions selected using lesion-symptom mapping. Our analysis showed that extracting features through patterns of voxels that represent lesion probability produced better results than quantifying the lesion load per region. In particular, from the different ways to delimit anatomical areas compared, the best performance was obtained with a combination of a range of cortical and subcortical motor areas as well as the corticospinal tract. These results will inform the appropriate methodology for predicting long term motor outcomes

  5. Error-correction coding and decoding bounds, codes, decoders, analysis and applications

    CERN Document Server

    Tomlinson, Martin; Ambroze, Marcel A; Ahmed, Mohammed; Jibril, Mubarak

    2017-01-01

    This book discusses both the theory and practical applications of self-correcting data, commonly known as error-correcting codes. The applications included demonstrate the importance of these codes in a wide range of everyday technologies, from smartphones to secure communications and transactions. Written in a readily understandable style, the book presents the authors’ twenty-five years of research organized into five parts: Part I is concerned with the theoretical performance attainable by using error correcting codes to achieve communications efficiency in digital communications systems. Part II explores the construction of error-correcting codes and explains the different families of codes and how they are designed. Techniques are described for producing the very best codes. Part III addresses the analysis of low-density parity-check (LDPC) codes, primarily to calculate their stopping sets and low-weight codeword spectrum which determines the performance of these codes. Part IV deals with decoders desi...

  6. Analysis of Minimal LDPC Decoder System on a Chip Implementation

    Directory of Open Access Journals (Sweden)

    T. Palenik

    2015-09-01

    Full Text Available This paper presents a practical method of potential replacement of several different Quasi-Cyclic Low-Density Parity-Check (QC-LDPC codes with one, with the intention of saving as much memory as required to implement the LDPC encoder and decoder in a memory-constrained System on a Chip (SoC. The presented method requires only a very small modification of the existing encoder and decoder, making it suitable for utilization in a Software Defined Radio (SDR platform. Besides the analysis of the effects of necessary variable-node value fixation during the Belief Propagation (BP decoding algorithm, practical standard-defined code parameters are scrutinized in order to evaluate the feasibility of the proposed LDPC setup simplification. Finally, the error performance of the modified system structure is evaluated and compared with the original system structure by means of simulation.

  7. [Efficacy of decoding training for children with difficulty reading hiragana].

    Science.gov (United States)

    Uchiyama, Hitoshi; Tanaka, Daisuke; Seki, Ayumi; Wakamiya, Eiji; Hirasawa, Noriko; Iketani, Naotake; Kato, Ken; Koeda, Tatsuya

    2013-05-01

    The present study aimed to clarify the efficacy of decoding training focusing on the correspondence between written symbols and their readings for children with difficulty reading hiragana (Japanese syllabary). Thirty-five children with difficulty reading hiragana were selected from among 367 first-grade elementary school students using a reading aloud test and were then divided into intervention (n=15) and control (n=20) groups. The intervention comprised 5 minutes of decoding training each day for a period of 3 weeks using an original program on a personal computer. Reading time and number of reading errors in the reading aloud test were compared between the groups. The intervention group showed a significant shortening of reading time (F(1,33)=5.40, preading errors was observed (t= 2.863, preading time. Decoding training was found to be effective for improving both reading time and reading errors in children with difficulty reading hiragana.

  8. Soft-decision Viterbi decoding with diversity combining

    Science.gov (United States)

    Sakai, T.; Kobayashi, K.; Kato, S.

    1990-01-01

    Diversity combining methods for convolutional coded and soft-decision Viterbi decoded channels in mobile satellite communications systems are evaluated and it is clarified that the pre-Viterbi-decoding maximal ratio combining shows better performance than other methods in Rician fading channels by computer simulation. A novel practical technique for maximal ratio combining is proposed, in which the coefficients for weighting are derived from soft-decision demodulated signals only. The proposed diversity combining method with soft-decision Viterbi decoding requires simple hardware and shows satisfactory performance with slight degradation of 0.3 dB in Rician fading channels compared with an ideal weighting scheme. Furthermore, this diversity method is applied to trellis coded modulation and significant Pe performance improvement is achieved.

  9. Image coding design considerations for cascaded encoding-decoding cycles and image editing: analysis of JPEG 1, JPEG 2000, and JPEG XR / HD Photo

    Science.gov (United States)

    Sullivan, Gary J.; Sun, Shijun; Regunathan, Shankar; Schonberg, Daniel; Tu, Chengjie; Srinivasan, Sridhar

    2008-08-01

    This paper discusses cascaded multiple encoding/decoding cycles and their effect on image quality for lossy image coding designs. Cascaded multiple encoding/decoding is an important operating scenario in professional editing industries. In such scenarios, it is common for a single image to be edited by several people while the image is compressed between editors for transit and archival. In these cases, it is important that decoding followed by re-encoding introduce minimal (or no) distortion across generations. A significant number of potential sources of distortion introduction exist in a cascade of decoding and re-encoding, especially if such processes as conversion between RGB and YUV color representations, 4:2:0 resampling, etc., are considered (and operations like spatial shifting, resizing, and changes of the quantization process or coding format). This paper highlights various aspects of distortion introduced by decoding and re-encoding, and remarks on the impact of these issues in the context of three still-image coding designs: JPEG, JPEG 2000, and JPEG XR. JPEG XR is a draft standard under development in the JPEG committee based on Microsoft technology known as HD Photo. The paper focuses particularly on the JPEG XR technology, and suggests that the design of the draft JPEG XR standard has several quite good characteristics in regard to re-encoding robustness.

  10. Joint Estimation and Decoding of Space-Time Trellis Codes

    Directory of Open Access Journals (Sweden)

    Zhang Jianqiu

    2002-01-01

    Full Text Available We explore the possibility of using an emerging tool in statistical signal processing, sequential importance sampling (SIS, for joint estimation and decoding of space-time trellis codes (STTC. First, we provide background on SIS, and then we discuss its application to space-time trellis code (STTC systems. It is shown through simulations that SIS is suitable for joint estimation and decoding of STTC with time-varying flat-fading channels when phase ambiguity is avoided. We used a design criterion for STTCs and temporally correlated channels that combats phase ambiguity without pilot signaling. We have shown by simulations that the design is valid.

  11. Efficient decoding of random errors for quantum expander codes

    OpenAIRE

    Fawzi , Omar; Grospellier , Antoine; Leverrier , Anthony

    2017-01-01

    We show that quantum expander codes, a constant-rate family of quantum LDPC codes, with the quasi-linear time decoding algorithm of Leverrier, Tillich and Z\\'emor can correct a constant fraction of random errors with very high probability. This is the first construction of a constant-rate quantum LDPC code with an efficient decoding algorithm that can correct a linear number of random errors with a negligible failure probability. Finding codes with these properties is also motivated by Gottes...

  12. Melodic intonation therapy in the verbal decoding of aphasics.

    Science.gov (United States)

    Popovici, M

    1995-01-01

    Melodic Intonation Therapy is a well-known method exploring the verbal encoding of aphasics but within this study, it was used to investigate the verbal decoding (the auditory comprehension). Two separate groups, 240 cases each, were investigated, the former with MIT and the latter with other therapy methods. Each group included three subgroups according to the three frequent types of aphasia (Wernicke, Broca and Anomia). The method of semantic fields was associated to treat the second group since it is usually used in the treatment of aphasics with auditory decoding disturbances. All patients were tested twice, before and after therapy.

  13. An online brain-machine interface using decoding of movement direction from the human electrocorticogram

    Science.gov (United States)

    Milekovic, Tomislav; Fischer, Jörg; Pistohl, Tobias; Ruescher, Johanna; Schulze-Bonhage, Andreas; Aertsen, Ad; Rickert, Jörn; Ball, Tonio; Mehring, Carsten

    2012-08-01

    A brain-machine interface (BMI) can be used to control movements of an artificial effector, e.g. movements of an arm prosthesis, by motor cortical signals that control the equivalent movements of the corresponding body part, e.g. arm movements. This approach has been successfully applied in monkeys and humans by accurately extracting parameters of movements from the spiking activity of multiple single neurons. We show that the same approach can be realized using brain activity measured directly from the surface of the human cortex using electrocorticography (ECoG). Five subjects, implanted with ECoG implants for the purpose of epilepsy assessment, took part in our study. Subjects used directionally dependent ECoG signals, recorded during active movements of a single arm, to control a computer cursor in one out of two directions. Significant BMI control was achieved in four out of five subjects with correct directional decoding in 69%-86% of the trials (75% on average). Our results demonstrate the feasibility of an online BMI using decoding of movement direction from human ECoG signals. Thus, to achieve such BMIs, ECoG signals might be used in conjunction with or as an alternative to intracortical neural signals.

  14. Do handwritten words magnify lexical effects in visual word recognition?

    Science.gov (United States)

    Perea, Manuel; Gil-López, Cristina; Beléndez, Victoria; Carreiras, Manuel

    2016-01-01

    An examination of how the word recognition system is able to process handwritten words is fundamental to formulate a comprehensive model of visual word recognition. Previous research has revealed that the magnitude of lexical effects (e.g., the word-frequency effect) is greater with handwritten words than with printed words. In the present lexical decision experiments, we examined whether the quality of handwritten words moderates the recruitment of top-down feedback, as reflected in word-frequency effects. Results showed a reading cost for difficult-to-read and easy-to-read handwritten words relative to printed words. But the critical finding was that difficult-to-read handwritten words, but not easy-to-read handwritten words, showed a greater word-frequency effect than printed words. Therefore, the inherent physical variability of handwritten words does not necessarily boost the magnitude of lexical effects.

  15. Algebraic decoder specification: coupling formal-language theory and statistical machine translation

    OpenAIRE

    Büchse, Matthias

    2015-01-01

    The specification of a decoder, i.e., a program that translates sentences from one natural language into another, is an intricate process, driven by the application and lacking a canonical methodology. The practical nature of decoder development inhibits the transfer of knowledge between theory and application, which is unfortunate because many contemporary decoders are in fact related to formal-language theory. This thesis proposes an algebraic framework where a decoder is specified by an ex...

  16. Separating the influences of prereading skills on early word and nonword reading.

    Science.gov (United States)

    Shapiro, Laura R; Carroll, Julia M; Solity, Jonathan E

    2013-10-01

    The essential first step for a beginning reader is to learn to match printed forms to phonological representations. For a new word, this is an effortful process where each grapheme must be translated individually (serial decoding). The role of phonological awareness in developing a decoding strategy is well known. We examined whether beginning readers recruit different skills depending on the nature of the words being read (familiar words vs. nonwords). Print knowledge, phoneme and rhyme awareness, rapid automatized naming (RAN), phonological short-term memory (STM), nonverbal reasoning, vocabulary, auditory skills, and visual attention were measured in 392 prereaders 4 and 5 years of age. Word and nonword reading were measured 9 months later. We used structural equation modeling to examine the skills-reading relationship and modeled correlations between our two reading outcomes and among all prereading skills. We found that a broad range of skills were associated with reading outcomes: early print knowledge, phonological STM, phoneme awareness and RAN. Whereas all of these skills were directly predictive of nonword reading, early print knowledge was the only direct predictor of word reading. Our findings suggest that beginning readers draw most heavily on their existing print knowledge to read familiar words. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Word graphs: The second set

    NARCIS (Netherlands)

    Hoede, C.; Liu, X

    1998-01-01

    In continuation of the paper of Hoede and Li on word graphs for a set of prepositions, word graphs are given for adjectives, adverbs and Chinese classifier words. It is argued that these three classes of words belong to a general class of words that may be called adwords. These words express the

  18. 47 CFR 11.12 - Two-tone Attention Signal encoder and decoder.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Two-tone Attention Signal encoder and decoder... SYSTEM (EAS) General § 11.12 Two-tone Attention Signal encoder and decoder. Existing two-tone Attention... Attention Signal decoder will no longer be required and the two-tone Attention Signal will be used to...

  19. Progressive Image Transmission Based on Joint Source-Channel Decoding Using Adaptive Sum-Product Algorithm

    Directory of Open Access Journals (Sweden)

    Liu Weiliang

    2007-01-01

    Full Text Available A joint source-channel decoding method is designed to accelerate the iterative log-domain sum-product decoding procedure of LDPC codes as well as to improve the reconstructed image quality. Error resilience modes are used in the JPEG2000 source codec making it possible to provide useful source decoded information to the channel decoder. After each iteration, a tentative decoding is made and the channel decoded bits are then sent to the JPEG2000 decoder. The positions of bits belonging to error-free coding passes are then fed back to the channel decoder. The log-likelihood ratios (LLRs of these bits are then modified by a weighting factor for the next iteration. By observing the statistics of the decoding procedure, the weighting factor is designed as a function of the channel condition. Results show that the proposed joint decoding methods can greatly reduce the number of iterations, and thereby reduce the decoding delay considerably. At the same time, this method always outperforms the nonsource controlled decoding method by up to 3 dB in terms of PSNR.

  20. Progressive Image Transmission Based on Joint Source-Channel Decoding Using Adaptive Sum-Product Algorithm

    Directory of Open Access Journals (Sweden)

    David G. Daut

    2007-03-01

    Full Text Available A joint source-channel decoding method is designed to accelerate the iterative log-domain sum-product decoding procedure of LDPC codes as well as to improve the reconstructed image quality. Error resilience modes are used in the JPEG2000 source codec making it possible to provide useful source decoded information to the channel decoder. After each iteration, a tentative decoding is made and the channel decoded bits are then sent to the JPEG2000 decoder. The positions of bits belonging to error-free coding passes are then fed back to the channel decoder. The log-likelihood ratios (LLRs of these bits are then modified by a weighting factor for the next iteration. By observing the statistics of the decoding procedure, the weighting factor is designed as a function of the channel condition. Results show that the proposed joint decoding methods can greatly reduce the number of iterations, and thereby reduce the decoding delay considerably. At the same time, this method always outperforms the nonsource controlled decoding method by up to 3 dB in terms of PSNR.

  1. tRNA's wobble decoding of the genome: 40 years of modification.

    Science.gov (United States)

    Agris, Paul F; Vendeix, Franck A P; Graham, William D

    2007-02-09

    The genetic code is degenerate, in that 20 amino acids are encoded by 61 triplet codes. In 1966, Francis Crick hypothesized that the cell's limited number of tRNAs decoded the genome by recognizing more than one codon. The ambiguity of that recognition resided in the third base-pair, giving rise to the Wobble Hypothesis. Post-transcriptional modifications at tRNA's wobble position 34, especially modifications of uridine 34, enable wobble to occur. The Modified Wobble Hypothesis proposed in 1991 that specific modifications of a tRNA wobble nucleoside shape the anticodon architecture in such a manner that interactions were restricted to the complementary base plus a single wobble pairing for amino acids with twofold degenerate codons. However, chemically different modifications at position 34 would expand the ability of a tRNA to read three or even four of the fourfold degenerate codons. One foundation of Crick's Wobble Hypothesis was that a near-constant geometry of canonical base-pairing be maintained in forming all three base-pairs between the tRNA anticodon and mRNA codon on the ribosome. In accepting an aminoacyl-tRNA, the ribosome requires maintenance of a specific geometry for the anticodon-codon base-pairing. However, it is the post-transcriptional modifications at tRNA wobble position 34 and purine 37, 3'-adjacent to the anticodon, that pre-structure the anticodon domain to ensure the correct codon binding. The modifications create both the architecture and the stability needed for decoding through restraints on anticodon stereochemistry and conformational space, and through selective hydrogen bonding. A physicochemical understanding of modified nucleoside contributions to the tRNA anticodon domain architecture and its decoding of the genome has advanced RNA world evolutionary theory, the principles of RNA chemistry, and the application of this knowledge to the introduction of new amino acids to proteins.

  2. Decoding humor experiences from brain activity of people viewing comedy movies.

    Science.gov (United States)

    Sawahata, Yasuhito; Komine, Kazuteru; Morita, Toshiya; Hiruma, Nobuyuki

    2013-01-01

    Humans naturally have a sense of humor. Experiencing humor not only encourages social interactions, but also produces positive physiological effects on the human body, such as lowering blood pressure. Recent neuro-imaging studies have shown evidence for distinct mental state changes at work in people experiencing humor. However, the temporal characteristics of these changes remain elusive. In this paper, we objectively measured humor-related mental states from single-trial functional magnetic resonance imaging (fMRI) data obtained while subjects viewed comedy TV programs. Measured fMRI data were labeled on the basis of the lag before or after the viewer's perception of humor (humor onset) determined by the viewer-reported humor experiences during the fMRI scans. We trained multiple binary classifiers, or decoders, to distinguish between fMRI data obtained at each lag from ones obtained during a neutral state in which subjects were not experiencing humor. As a result, in the right dorsolateral prefrontal cortex and the right temporal area, the decoders showed significant classification accuracies even at two seconds ahead of the humor onsets. Furthermore, given a time series of fMRI data obtained during movie viewing, we found that the decoders with significant performance were also able to predict the upcoming humor events on a volume-by-volume basis. Taking into account the hemodynamic delay, our results suggest that the upcoming humor events are encoded in specific brain areas up to about five seconds before the awareness of experiencing humor. Our results provide evidence that there exists a mental state lasting for a few seconds before actual humor perception, as if a viewer is expecting the future humorous events.

  3. Real-time decoding of the direction of covert visuospatial attention

    Science.gov (United States)

    Andersson, Patrik; Ramsey, Nick F.; Raemaekers, Mathijs; Viergever, Max A.; Pluim, Josien P. W.

    2012-08-01

    Brain-computer interfaces (BCIs) make it possible to translate a person’s intentions into actions without depending on the muscular system. Brain activity is measured and classified into commands, thereby creating a direct link between the mind and the environment, enabling, e.g., cursor control or navigation of a wheelchair or robot. Most BCI research is conducted with scalp EEG but recent developments move toward intracranial electrodes for paralyzed people. The vast majority of BCI studies focus on the motor system as the appropriate target for recording and decoding movement intentions. However, properties of the visual system may make the visual system an attractive and intuitive alternative. We report on a study investigating feasibility of decoding covert visuospatial attention in real time, exploiting the full potential of a 7 T MRI scanner to obtain the necessary signal quality, capitalizing on earlier fMRI studies indicating that covert visuospatial attention changes activity in the visual areas that respond to stimuli presented in the attended area of the visual field. Healthy volunteers were instructed to shift their attention from the center of the screen to one of four static targets in the periphery, without moving their eyes from the center. During the first part of the fMRI-run, the relevant brain regions were located using incremental statistical analysis. During the second part, the activity in these regions was extracted and classified, and the subject was given visual feedback of the result. Performance was assessed as the number of trials where the real-time classifier correctly identified the direction of attention. On average, 80% of trials were correctly classified (chance level <25%) based on a single image volume, indicating very high decoding performance. While we restricted the experiment to five attention target regions (four peripheral and one central), the number of directions can be higher provided the brain activity patterns can

  4. Decoding Humor Experiences from Brain Activity of People Viewing Comedy Movies

    Science.gov (United States)

    Sawahata, Yasuhito; Komine, Kazuteru; Morita, Toshiya; Hiruma, Nobuyuki

    2013-01-01

    Humans naturally have a sense of humor. Experiencing humor not only encourages social interactions, but also produces positive physiological effects on the human body, such as lowering blood pressure. Recent neuro-imaging studies have shown evidence for distinct mental state changes at work in people experiencing humor. However, the temporal characteristics of these changes remain elusive. In this paper, we objectively measured humor-related mental states from single-trial functional magnetic resonance imaging (fMRI) data obtained while subjects viewed comedy TV programs. Measured fMRI data were labeled on the basis of the lag before or after the viewer’s perception of humor (humor onset) determined by the viewer-reported humor experiences during the fMRI scans. We trained multiple binary classifiers, or decoders, to distinguish between fMRI data obtained at each lag from ones obtained during a neutral state in which subjects were not experiencing humor. As a result, in the right dorsolateral prefrontal cortex and the right temporal area, the decoders showed significant classification accuracies even at two seconds ahead of the humor onsets. Furthermore, given a time series of fMRI data obtained during movie viewing, we found that the decoders with significant performance were also able to predict the upcoming humor events on a volume-by-volume basis. Taking into account the hemodynamic delay, our results suggest that the upcoming humor events are encoded in specific brain areas up to about five seconds before the awareness of experiencing humor. Our results provide evidence that there exists a mental state lasting for a few seconds before actual humor perception, as if a viewer is expecting the future humorous events. PMID:24324656

  5. Activation of extrastriate and frontal cortical areas by visual words and word-like stimuli

    International Nuclear Information System (INIS)

    Petersen, S.E.; Fox, P.T.; Snyder, A.Z.; Raichle, M.E.

    1990-01-01

    Visual presentation of words activates extrastriate regions of the occipital lobes of the brain. When analyzed by positron emission tomography (PET), certain areas in the left, medial extrastriate visual cortex were activated by visually presented pseudowords that obey English spelling rules, as well as by actual words. These areas were not activated by nonsense strings of letters or letter-like forms. Thus visual word form computations are based on learned distinctions between words and nonwords. In addition, during passive presentation of words, but not pseudowords, activation occurred in a left frontal area that is related to semantic processing. These findings support distinctions made in cognitive psychology and computational modeling between high-level visual and semantic computations on single words and describe the anatomy that may underlie these distinctions

  6. Word 2010 Bible

    CERN Document Server

    Tyson, Herb

    2010-01-01

    In-depth guidance on Word 2010 from a Microsoft MVP. Microsoft Word 2010 arrives with many changes and improvements, and this comprehensive guide from Microsoft MVP Herb Tyson is your expert, one-stop resource for it all. Master Word's new features such as a new interface and customized Ribbon, major new productivity-boosting collaboration tools, how to publish directly to blogs, how to work with XML, and much more. Follow step-by-step instructions and best practices, avoid pitfalls, discover practical workarounds, and get the very most out of your new Word 2010 with this packed guide. Coverag

  7. Decoding English Alphabet Letters Using EEG Phase Information

    Science.gov (United States)

    Wang, YiYan; Wang, Pingxiao; Yu, Yuguo

    2018-01-01

    Increasing evidence indicates that the phase pattern and power of the low frequency oscillations of brain electroencephalograms (EEG) contain significant information during the human cognition of sensory signals such as auditory and visual stimuli. Here, we investigate whether and how the letters of the alphabet can be directly decoded from EEG phase and power data. In addition, we investigate how different band oscillations contribute to the classification and determine the critical time periods. An English letter recognition task was assigned, and statistical analyses were conducted to decode the EEG signal corresponding to each letter visualized on a computer screen. We applied support vector machine (SVM) with gradient descent method to learn the potential features for classification. It was observed that the EEG phase signals have a higher decoding accuracy than the oscillation power information. Low-frequency theta and alpha oscillations have phase information with higher accuracy than do other bands. The decoding performance was best when the analysis period began from 180 to 380 ms after stimulus presentation, especially in the lateral occipital and posterior temporal scalp regions (PO7 and PO8). These results may provide a new approach for brain-computer interface techniques (BCI) and may deepen our understanding of EEG oscillations in cognition. PMID:29467615

  8. The Interactions of Vocabulary, Phonemic Awareness, Decoding, and Reading Comprehension

    Science.gov (United States)

    Carlson, Elaine; Jenkins, Frank; Li, Tiandong; Brownell, Mary

    2013-01-01

    The authors used data from a large, national sample to examine the interaction of various literacy measures among young children with disabilities. Using structural equation modeling, they examined the relationships among measures of phonemic awareness, decoding, vocabulary, and reading comprehension. Child and family factors, including sex,…

  9. The Development of the Graphics-Decoding Proficiency Instrument

    Science.gov (United States)

    Lowrie, Tom; Diezmann, Carmel M.; Kay, Russell

    2011-01-01

    The graphics-decoding proficiency (G-DP) instrument was developed as a screening test for the purpose of measuring students' (aged 8-11 years) capacity to solve graphics-based mathematics tasks. These tasks include number lines, column graphs, maps and pie charts. The instrument was developed within a theoretical framework which highlights the…

  10. A quantum algorithm for Viterbi decoding of classical convolutional codes

    Science.gov (United States)

    Grice, Jon R.; Meyer, David A.

    2015-07-01

    We present a quantum Viterbi algorithm (QVA) with better than classical performance under certain conditions. In this paper, the proposed algorithm is applied to decoding classical convolutional codes, for instance, large constraint length and short decode frames . Other applications of the classical Viterbi algorithm where is large (e.g., speech processing) could experience significant speedup with the QVA. The QVA exploits the fact that the decoding trellis is similar to the butterfly diagram of the fast Fourier transform, with its corresponding fast quantum algorithm. The tensor-product structure of the butterfly diagram corresponds to a quantum superposition that we show can be efficiently prepared. The quantum speedup is possible because the performance of the QVA depends on the fanout (number of possible transitions from any given state in the hidden Markov model) which is in general much less than . The QVA constructs a superposition of states which correspond to all legal paths through the decoding lattice, with phase as a function of the probability of the path being taken given received data. A specialized amplitude amplification procedure is applied one or more times to recover a superposition where the most probable path has a high probability of being measured.

  11. Music models aberrant rule decoding and reward valuation in dementia.

    Science.gov (United States)

    Clark, Camilla N; Golden, Hannah L; McCallion, Oliver; Nicholas, Jennifer M; Cohen, Miriam H; Slattery, Catherine F; Paterson, Ross W; Fletcher, Phillip D; Mummery, Catherine J; Rohrer, Jonathan D; Crutch, Sebastian J; Warren, Jason D

    2018-02-01

    Aberrant rule- and reward-based processes underpin abnormalities of socio-emotional behaviour in major dementias. However, these processes remain poorly characterized. Here we used music to probe rule decoding and reward valuation in patients with frontotemporal dementia (FTD) syndromes and Alzheimer's disease (AD) relative to healthy age-matched individuals. We created short melodies that were either harmonically resolved ('finished') or unresolved ('unfinished'); the task was to classify each melody as finished or unfinished (rule processing) and rate its subjective pleasantness (reward valuation). Results were adjusted for elementary pitch and executive processing; neuroanatomical correlates were assessed using voxel-based morphometry. Relative to healthy older controls, patients with behavioural variant FTD showed impairments of both musical rule decoding and reward valuation, while patients with semantic dementia showed impaired reward valuation but intact rule decoding, patients with AD showed impaired rule decoding but intact reward valuation and patients with progressive non-fluent aphasia performed comparably to healthy controls. Grey matter associations with task performance were identified in anterior temporal, medial and lateral orbitofrontal cortices, previously implicated in computing diverse biological and non-biological rules and rewards. The processing of musical rules and reward distils cognitive and neuroanatomical mechanisms relevant to complex socio-emotional dysfunction in major dementias.

  12. Name that tune: Decoding music from the listening brain

    NARCIS (Netherlands)

    Schaefer, R.S.; Farquhar, J.D.R.; Blokland, Y.M.; Sadakata, M.; Desain, P.W.M.

    2011-01-01

    In the current study we use electroencephalography (EEG) to detect heard music from the brain signal, hypothesizing that the time structure in music makes it especially suitable for decoding perception from EEG signals. While excluding music with vocals, we classified the perception of seven

  13. Name that tune: decoding music from the listening brain.

    NARCIS (Netherlands)

    Schaefer, R.S.; Farquhar, J.D.R.; Blokland, Y.M.; Sadakata, M.; Desain, P.W.M.

    2011-01-01

    In the current study we use electroencephalography (EEG) to detect heard music from the brain signal, hypothesizing that the time structure in music makes it especially suitable for decoding perception from EEG signals. While excluding music with vocals, we classified the perception of seven

  14. Real Time Decoding of Color Symbol for Optical Positioning System

    Directory of Open Access Journals (Sweden)

    Abdul Waheed Malik

    2015-01-01

    Full Text Available This paper presents the design and real-time decoding of a color symbol that can be used as a reference marker for optical navigation. The designed symbol has a circular shape and is printed on paper using two distinct colors. This pair of colors is selected based on the highest achievable signal to noise ratio. The symbol is designed to carry eight bit information. Real time decoding of this symbol is performed using a heterogeneous combination of Field Programmable Gate Array (FPGA and a microcontroller. An image sensor having a resolution of 1600 by 1200 pixels is used to capture images of symbols in complex backgrounds. Dynamic image segmentation, component labeling and feature extraction was performed on the FPGA. The region of interest was further computed from the extracted features. Feature data belonging to the symbol was sent from the FPGA to the microcontroller. Image processing tasks are partitioned between the FPGA and microcontroller based on data intensity. Experiments were performed to verify the rotational independence of the symbols. The maximum distance between camera and symbol allowing for correct detection and decoding was analyzed. Experiments were also performed to analyze the number of generated image components and sub-pixel precision versus different light sources and intensities. The proposed hardware architecture can process up to 55 frames per second for accurate detection and decoding of symbols at two Megapixels resolution. The power consumption of the complete system is 342mw.

  15. Adaptive Combined Source and Channel Decoding with Modulation ...

    African Journals Online (AJOL)

    In this paper, an adaptive system employing combined source and channel decoding with modulation is proposed for slow Rayleigh fading channels. Huffman code is used as the source code and Convolutional code is used for error control. The adaptive scheme employs a family of Convolutional codes of different rates ...

  16. Peeling Decoding of LDPC Codes with Applications in Compressed Sensing

    Directory of Open Access Journals (Sweden)

    Weijun Zeng

    2016-01-01

    Full Text Available We present a new approach for the analysis of iterative peeling decoding recovery algorithms in the context of Low-Density Parity-Check (LDPC codes and compressed sensing. The iterative recovery algorithm is particularly interesting for its low measurement cost and low computational complexity. The asymptotic analysis can track the evolution of the fraction of unrecovered signal elements in each iteration, which is similar to the well-known density evolution analysis in the context of LDPC decoding algorithm. Our analysis shows that there exists a threshold on the density factor; if under this threshold, the recovery algorithm is successful; otherwise it will fail. Simulation results are also provided for verifying the agreement between the proposed asymptotic analysis and recovery algorithm. Compared with existing works of peeling decoding algorithm, focusing on the failure probability of the recovery algorithm, our proposed approach gives accurate evolution of performance with different parameters of measurement matrices and is easy to implement. We also show that the peeling decoding algorithm performs better than other schemes based on LDPC codes.

  17. Decoding the Disciplines: An Approach to Scientific Thinking

    Science.gov (United States)

    Pinnow, Eleni

    2016-01-01

    The Decoding the Disciplines methodology aims to teach students to think like experts in discipline-specific tasks. The central aspect of the methodology is to identify a bottleneck in the course content: a particular topic that a substantial number of students struggle to master. The current study compared the efficacy of standard lecture and…

  18. Precoder and decoder prediction in time-varying MIMO channel

    DEFF Research Database (Denmark)

    Nguyen, Tuan Hung; Leus, Geert; Khaled, Nadia

    2005-01-01

    the performance of a prediction scheme for multiple input multiple output (MIMO) systems that apply spatial multiplexing. We aim at predicting the future precoder/decoder directly without going through the prediction of the channel matrix. The results show that in a slowly time varying channel an increase...

  19. Decoding sound level in the marmoset primary auditory cortex.

    Science.gov (United States)

    Sun, Wensheng; Marongelli, Ellisha N; Watkins, Paul V; Barbour, Dennis L

    2017-10-01

    Neurons that respond favorably to a particular sound level have been observed throughout the central auditory system, becoming steadily more common at higher processing areas. One theory about the role of these level-tuned or nonmonotonic neurons is the level-invariant encoding of sounds. To investigate this theory, we simulated various subpopulations of neurons by drawing from real primary auditory cortex (A1) neuron responses and surveyed their performance in forming different sound level representations. Pure nonmonotonic subpopulations did not provide the best level-invariant decoding; instead, mixtures of monotonic and nonmonotonic neurons provided the most accurate decoding. For level-fidelity decoding, the inclusion of nonmonotonic neurons slightly improved or did not change decoding accuracy until they constituted a high proportion. These results indicate that nonmonotonic neurons fill an encoding role complementary to, rather than alternate to, monotonic neurons. NEW & NOTEWORTHY Neurons with nonmonotonic rate-level functions are unique to the central auditory system. These level-tuned neurons have been proposed to account for invariant sound perception across sound levels. Through systematic simulations based on real neuron responses, this study shows that neuron populations perform sound encoding optimally when containing both monotonic and nonmonotonic neurons. The results indicate that instead of working independently, nonmonotonic neurons complement the function of monotonic neurons in different sound-encoding contexts. Copyright © 2017 the American Physiological Society.

  20. Vocabulary knowledge mediates the link between socioeconomic status and word learning in grade school.

    Science.gov (United States)

    Maguire, Mandy J; Schneider, Julie M; Middleton, Anna E; Ralph, Yvonne; Lopez, Michael; Ackerman, Robert A; Abel, Alyson D

    2018-02-01

    The relationship between children's slow vocabulary growth and the family's low socioeconomic status (SES) has been well documented. However, previous studies have often focused on infants or preschoolers and primarily used static measures of vocabulary at multiple time points. To date, there is no research investigating whether SES predicts a child's word learning abilities in grade school and, if so, what mediates this relationship. In this study, 68 children aged 8-15 years performed a written word learning from context task that required using the surrounding text to identify the meaning of an unknown word. Results revealed that vocabulary knowledge significantly mediated the relationship between SES (as measured by maternal education) and word learning. This was true despite the fact that the words in the linguistic context surrounding the target word are typically acquired well before 8 years of age. When controlling for vocabulary, word learning from written context was not predicted by differences in reading comprehension, decoding, or working memory. These findings reveal that differences in vocabulary growth between grade school children from low and higher SES homes are likely related to differences in the process of word learning more than knowledge of surrounding words or reading skills. Specifically, children from lower SES homes are not as effective at using known vocabulary to build a robust semantic representation of incoming text to identify the meaning of an unknown word. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Nurturing a lexical legacy: reading experience is critical for the development of word reading skill

    Science.gov (United States)

    Nation, Kate

    2017-12-01

    The scientific study of reading has taught us much about the beginnings of reading in childhood, with clear evidence that the gateway to reading opens when children are able to decode, or `sound out' written words. Similarly, there is a large evidence base charting the cognitive processes that characterise skilled word recognition in adults. Less understood is how children develop word reading expertise. Once basic reading skills are in place, what factors are critical for children to move from novice to expert? This paper outlines the role of reading experience in this transition. Encountering individual words in text provides opportunities for children to refine their knowledge about how spelling represents spoken language. Alongside this, however, reading experience provides much more than repeated exposure to individual words in isolation. According to the lexical legacy perspective, outlined in this paper, experiencing words in diverse and meaningful language environments is critical for the development of word reading skill. At its heart is the idea that reading provides exposure to words in many different contexts, episodes and experiences which, over time, sum to a rich and nuanced database about their lexical history within an individual's experience. These rich and diverse encounters bring about local variation at the word level: a lexical legacy that is measurable during word reading behaviour, even in skilled adults.

  2. Word of Jeremiah - Word of God

    DEFF Research Database (Denmark)

    Holt, Else Kragelund

    2007-01-01

    The article examines the relationship between God, prophet and the people in the Book of Jeremiah. The analysis shows a close connection, almost an identification, between the divine word (and consequently God himself) and the prophet, so that the prophet becomes a metaphor for God. This is done...

  3. On Lattice Sequential Decoding for Large MIMO Systems

    KAUST Repository

    Ali, Konpal S.

    2014-04-01

    Due to their ability to provide high data rates, Multiple-Input Multiple-Output (MIMO) wireless communication systems have become increasingly popular. Decoding of these systems with acceptable error performance is computationally very demanding. In the case of large overdetermined MIMO systems, we employ the Sequential Decoder using the Fano Algorithm. A parameter called the bias is varied to attain different performance-complexity trade-offs. Low values of the bias result in excellent performance but at the expense of high complexity and vice versa for higher bias values. We attempt to bound the error by bounding the bias, using the minimum distance of a lattice. Also, a particular trend is observed with increasing SNR: a region of low complexity and high error, followed by a region of high complexity and error falling, and finally a region of low complexity and low error. For lower bias values, the stages of the trend are incurred at lower SNR than for higher bias values. This has the important implication that a low enough bias value, at low to moderate SNR, can result in low error and low complexity even for large MIMO systems. Our work is compared against Lattice Reduction (LR) aided Linear Decoders (LDs). Another impressive observation for low bias values that satisfy the error bound is that the Sequential Decoder\\'s error is seen to fall with increasing system size, while it grows for the LR-aided LDs. For the case of large underdetermined MIMO systems, Sequential Decoding with two preprocessing schemes is proposed – 1) Minimum Mean Square Error Generalized Decision Feedback Equalization (MMSE-GDFE) preprocessing 2) MMSE-GDFE preprocessing, followed by Lattice Reduction and Greedy Ordering. Our work is compared against previous work which employs Sphere Decoding preprocessed using MMSE-GDFE, Lattice Reduction and Greedy Ordering. For the case of large systems, this results in high complexity and difficulty in choosing the sphere radius. Our schemes

  4. Automatic detection and decoding of honey bee waggle dances.

    Directory of Open Access Journals (Sweden)

    Fernando Wario

    Full Text Available The waggle dance is one of the most popular examples of animal communication. Forager bees direct their nestmates to profitable resources via a complex motor display. Essentially, the dance encodes the polar coordinates to the resource in the field. Unemployed foragers follow the dancer's movements and then search for the advertised spots in the field. Throughout the last decades, biologists have employed different techniques to measure key characteristics of the waggle dance and decode the information it conveys. Early techniques involved the use of protractors and stopwatches to measure the dance orientation and duration directly from the observation hive. Recent approaches employ digital video recordings and manual measurements on screen. However, manual approaches are very time-consuming. Most studies, therefore, regard only small numbers of animals in short periods of time. We have developed a system capable of automatically detecting, decoding and mapping communication dances in real-time. In this paper, we describe our recording setup, the image processing steps performed for dance detection and decoding and an algorithm to map dances to the field. The proposed system performs with a detection accuracy of 90.07%. The decoded waggle orientation has an average error of -2.92° (± 7.37°, well within the range of human error. To evaluate and exemplify the system's performance, a group of bees was trained to an artificial feeder, and all dances in the colony were automatically detected, decoded and mapped. The system presented here is the first of this kind made publicly available, including source code and hardware specifications. We hope this will foster quantitative analyses of the honey bee waggle dance.

  5. Word Processing for All.

    Science.gov (United States)

    Abbott, Chris

    1991-01-01

    Pupils with special educational needs are finding that the use of word processors can give them a new confidence and pride in their own abilities. This article describes the use of such devices as the "mouse," on-screen word lists, spell checkers, and overlay keyboards. (JDD)

  6. Visual Word Ambiguity

    NARCIS (Netherlands)

    van Gemert, J.C.; Veenman, C.J.; Smeulders, A.W.M.; Geusebroek, J.M.

    2010-01-01

    This paper studies automatic image classification by modeling soft assignment in the popular codebook model. The codebook model describes an image as a bag of discrete visual words selected from a vocabulary, where the frequency distributions of visual words in an image allow classification. One

  7. WordPress Bible

    CERN Document Server

    Brazell, Aaron

    2011-01-01

    Get the latest word on the biggest self-hosted blogging tool on the marketWithin a week of the announcement of WordPress 3.0, it had been downloaded over a million times. Now you can get on the bandwagon of this popular open-source blogging tool with WordPress Bible, 2nd Edition. Whether you're a casual blogger or programming pro, this comprehensive guide covers the latest version of WordPress, from the basics through advanced application development. If you want to thoroughly learn WordPress, this is the book you need to succeed.Explores the principles of blogging, marketing, and social media

  8. Decoding the genome with an integrative analysis tool: combinatorial CRM Decoder.

    Science.gov (United States)

    Kang, Keunsoo; Kim, Joomyeong; Chung, Jae Hoon; Lee, Daeyoup

    2011-09-01

    The identification of genome-wide cis-regulatory modules (CRMs) and characterization of their associated epigenetic features are fundamental steps toward the understanding of gene regulatory networks. Although integrative analysis of available genome-wide information can provide new biological insights, the lack of novel methodologies has become a major bottleneck. Here, we present a comprehensive analysis tool called combinatorial CRM decoder (CCD), which utilizes the publicly available information to identify and characterize genome-wide CRMs in a species of interest. CCD first defines a set of the epigenetic features which is significantly associated with a set of known CRMs as a code called 'trace code', and subsequently uses the trace code to pinpoint putative CRMs throughout the genome. Using 61 genome-wide data sets obtained from 17 independent mouse studies, CCD successfully catalogued ∼12 600 CRMs (five distinct classes) including polycomb repressive complex 2 target sites as well as imprinting control regions. Interestingly, we discovered that ∼4% of the identified CRMs belong to at least two different classes named 'multi-functional CRM', suggesting their functional importance for regulating spatiotemporal gene expression. From these examples, we show that CCD can be applied to any potential genome-wide datasets and therefore will shed light on unveiling genome-wide CRMs in various species.

  9. Spiking neural circuits with dendritic stimulus processors : encoding, decoding, and identification in reproducing kernel Hilbert spaces.

    Science.gov (United States)

    Lazar, Aurel A; Slutskiy, Yevgeniy B

    2015-02-01

    We present a multi-input multi-output neural circuit architecture for nonlinear processing and encoding of stimuli in the spike domain. In this architecture a bank of dendritic stimulus processors implements nonlinear transformations of multiple temporal or spatio-temporal signals such as spike trains or auditory and visual stimuli in the analog domain. Dendritic stimulus processors may act on both individual stimuli and on groups of stimuli, thereby executing complex computations that arise as a result of interactions between concurrently received signals. The results of the analog-domain computations are then encoded into a multi-dimensional spike train by a population of spiking neurons modeled as nonlinear dynamical systems. We investigate general conditions under which such circuits faithfully represent stimuli and demonstrate algorithms for (i) stimulus recovery, or decoding, and (ii) identification of dendritic stimulus processors from the observed spikes. Taken together, our results demonstrate a fundamental duality between the identification of the dendritic stimulus processor of a single neuron and the decoding of stimuli encoded by a population of neurons with a bank of dendritic stimulus processors. This duality result enabled us to derive lower bounds on the number of experiments to be performed and the total number of spikes that need to be recorded for identifying a neural circuit.

  10. The Power Decoder Simulator for the Evaluation of Pooled shRNA Screen Performance.

    Science.gov (United States)

    Stombaugh, Jesse; Licon, Abel; Strezoska, Žaklina; Stahl, Joshua; Anderson, Sarah Bael; Banos, Michael; van Brabant Smith, Anja; Birmingham, Amanda; Vermeulen, Annaleen

    2015-09-01

    RNA interference screening using pooled, short hairpin RNA (shRNA) is a powerful, high-throughput tool for determining the biological relevance of genes for a phenotype. Assessing an shRNA pooled screen's performance is difficult in practice; one can estimate the performance only by using reproducibility as a proxy for power or by employing a large number of validated positive and negative controls. Here, we develop an open-source software tool, the Power Decoder simulator, for generating shRNA pooled screening experiments in silico that can be used to estimate a screen's statistical power. Using the negative binomial distribution, it models both the relative abundance of multiple shRNAs within a single screening replicate and the biological noise between replicates for each individual shRNA. We demonstrate that this simulator can successfully model the data from an actual laboratory experiment. We then use it to evaluate the effects of biological replicates and sequencing counts on the performance of a pooled screen, without the necessity of gathering additional data. The Power Decoder simulator is written in R and Python and is available for download under the GNU General Public License v3.0. © 2015 Society for Laboratory Automation and Screening.

  11. Improving throughput of single-relay DF channel using linear constellation precoding

    KAUST Repository

    Fareed, Muhammad Mehboob

    2014-08-01

    In this letter, we propose a transmission scheme to improve the overall throughput of a cooperative communication system with single decode-and-forward relay. Symbol error rate and throughput analysis of the new scheme are presented to facilitate the performance comparison with the existing decode-and-forward relaying schemes. Simulation results are further provided to corroborate the analytical results. © 2012 IEEE.

  12. The Effects of Visual Attention Span and Phonological Decoding in Reading Comprehension in Dyslexia: A Path Analysis

    OpenAIRE

    Chen, C.; Schneps, M.; Masyn, K.; Thomson, J.

    2016-01-01

    Increasing evidence has shown visual attention span to be a factor, distinct from phonological skills, that explains single-word identification (pseudo-word/word reading) performance in dyslexia. Yet, little is known about how well visual attention span explains text comprehension. Observing reading comprehension in a sample of 105 high school students with dyslexia, we used a pathway analysis to examine the direct and indirect path between visual attention span and reading comprehension whil...

  13. Correlation between Phonological and Morphological Awareness and the Reading of Punctuated and Non-Punctuated Words in Arabic as First Language and Hebrew as Second Language

    Science.gov (United States)

    Bishara, Saied; Weiss, Itzhak

    2017-01-01

    Phonological and morphological awareness and its correlation with reading punctuated and non-punctuated words in Arabic as a first language were examined, as well as its transfer to Hebrew as a second language. Research participants were 30 fourth grade pupils. Phonological awareness was examined by phonological decoding of actual and meaningless…

  14. A question of words.

    Science.gov (United States)

    Mains, Heather

    2003-01-01

    By tracing powerful patriarchal words originally applied to mass production, military manoeuvres, building construction and war, and then ascribing them to birth we can see how Western culture denounces the mother's true role as the central and essential figure in the birth of her own children. Many words for birth imply fear, doubt and opposition. Yet when we consciously select words to describe giving birth as a form of art--a giving of creation--we can not only place the woman at the centre of the birth event, but also grant the respect and honour due her as she brings forth new life.

  15. Prosody and Spoken Word Recognition in Early and Late Spanish-English Bilingual Individuals

    Science.gov (United States)

    Boutsen, Frank R.; Dvorak, Justin D.; Deweber, Derick D.

    2017-01-01

    Purpose: This study was conducted to compare the influence of word properties on gated single-word recognition in monolingual and bilingual individuals under conditions of native and nonnative accent and to determine whether word-form prosody facilitates recognition in bilingual individuals. Method: Word recognition was assessed in monolingual and…

  16. Neural decoding of attentional selection in multi-speaker environments without access to clean sources

    Science.gov (United States)

    O’Sullivan, James; Chen, Zhuo; Herrero, Jose; McKhann, Guy M.; Sheth, Sameer A.; Mehta, Ashesh D.; Mesgarani, Nima

    2017-10-01

    Objective. People who suffer from hearing impairments can find it difficult to follow a conversation in a multi-speaker environment. Current hearing aids can suppress background noise; however, there is little that can be done to help a user attend to a single conversation amongst many without knowing which speaker the user is attending to. Cognitively controlled hearing aids that use auditory attention decoding (AAD) methods are the next step in offering help. Translating the successes in AAD research to real-world applications poses a number of challenges, including the lack of access to the clean sound sources in the environment with which to compare with the neural signals. We propose a novel framework that combines single-channel speech separation algorithms with AAD. Approach. We present an end-to-end system that (1) receives a single audio channel containing a mixture of speakers that is heard by a listener along with the listener’s neural signals, (2) automatically separates the individual speakers in the mixture, (3) determines the attended speaker, and (4) amplifies the attended speaker’s voice to assist the listener. Main results. Using invasive electrophysiology recordings, we identified the regions of the auditory cortex that contribute to AAD. Given appropriate electrode locations, our system is able to decode the attention of subjects and amplify the attended speaker using only the mixed audio. Our quality assessment of the modified audio demonstrates a significant improvement in both subjective and objective speech quality measures. Significance. Our novel framework for AAD bridges the gap between the most recent advancements in speech processing technologies and speech prosthesis research and moves us closer to the development of cognitively controlled hearable devices for the hearing impaired.

  17. Neural decoding of attentional selection in multi-speaker environments without access to clean sources.

    Science.gov (United States)

    O'Sullivan, James; Chen, Zhuo; Herrero, Jose; McKhann, Guy M; Sheth, Sameer A; Mehta, Ashesh D; Mesgarani, Nima

    2017-10-01

    People who suffer from hearing impairments can find it difficult to follow a conversation in a multi-speaker environment. Current hearing aids can suppress background noise; however, there is little that can be done to help a user attend to a single conversation amongst many without knowing which speaker the user is attending to. Cognitively controlled hearing aids that use auditory attention decoding (AAD) methods are the next step in offering help. Translating the successes in AAD research to real-world applications poses a number of challenges, including the lack of access to the clean sound sources in the environment with which to compare with the neural signals. We propose a novel framework that combines single-channel speech separation algorithms with AAD. We present an end-to-end system that (1) receives a single audio channel containing a mixture of speakers that is heard by a listener along with the listener's neural signals, (2) automatically separates the individual speakers in the mixture, (3) determines the attended speaker, and (4) amplifies the attended speaker's voice to assist the listener. Using invasive electrophysiology recordings, we identified the regions of the auditory cortex that contribute to AAD. Given appropriate electrode locations, our system is able to decode the attention of subjects and amplify the attended speaker using only the mixed audio. Our quality assessment of the modified audio demonstrates a significant improvement in both subjective and objective speech quality measures. Our novel framework for AAD bridges the gap between the most recent advancements in speech processing technologies and speech prosthesis research and moves us closer to the development of cognitively controlled hearable devices for the hearing impaired.

  18. Words that Pop!

    Science.gov (United States)

    Russell, Shirley

    1988-01-01

    To excite students' appreciation of language, comic book words--onomatopoeia--are a useful tool. Exercises and books are suggested. A list of books for adults and children is recommended, and a reproducible page is provided. (JL)

  19. Greater pre-stimulus effective connectivity from the left inferior frontal area to other areas is associated with better phonological decoding in dyslexic readers

    Directory of Open Access Journals (Sweden)

    Richard E Frye

    2010-12-01

    Full Text Available Functional neuroimaging studies suggest that neural networks that subserve reading are organized differently in dyslexic readers (DRs and typical readers (TRs, yet the hierarchical structure of these networks has not been well studied. We used Granger Causality (GC to examine the effective connectivity of the preparatory network that occurs prior to viewing a non-word stimulus that requires phonological decoding in 7 DRs and 10 TRs who were young adults. The neuromagnetic activity that occurred 500 ms prior to each rhyme trial was analyzed from sensors overlying the left and right inferior frontal areas (IFA, temporoparietal areas (TPA, and ventral occipitotemporal areas (VOTA within the low, medium, and high beta and gamma sub-bands. A mixed-model analysis determined whether connectivity to or from the left and right IFAs differed across connectivity direction (into vs. out of the IFAs, brain areas, reading group, and/or performance. Results indicated that greater connectivity in the low beta sub-band from the left IFA to other cortical areas was significantly related to better non-word rhyme discrimination in DRs but not TRs. This suggests that the left IFA is an important cortical area involved in compensating for poor phonological function in DRs. We suggest that the left IFA activates a wider-than usual network prior to each trial in the service of supporting otherwise effortful phonological decoding in DRs. The fact that the left IFA provides top-down activation to both posterior left hemispheres areas used by typical readers for phonological decoding and homologous right hemisphere areas is discussed. In contrast, within the high gamma sub-band, better performance was associated with decreased connectivity between the left IFA and other brain areas, in both reading groups. Overly strong gamma connectivity during the pre-stimulus period may interfere with subsequent transient activation and deactivation of sub-networks once the non-word

  20. Flexible Word Classes

    DEFF Research Database (Denmark)

    van Lier, Eva; Rijkhoff, Jan

    2013-01-01

    • First major publication on the phenomenon • Offers cross-linguistic, descriptive, and diverse theoretical approaches • Includes analysis of data from different language families and from lesser studied languages This book is the first major cross-linguistic study of 'flexible words', i.e. words...... Indonesian, Santali, Sri Lanka Malay, Lushootseed, Gooniyandi, and Late Archaic Chinese. Readership: Linguists and students of linguistics and cognitive sciences, anthropologists, philosophers...

  1. Reaction Decoder Tool (RDT): extracting features from chemical reactions.

    Science.gov (United States)

    Rahman, Syed Asad; Torrance, Gilliean; Baldacci, Lorenzo; Martínez Cuesta, Sergio; Fenninger, Franz; Gopal, Nimish; Choudhary, Saket; May, John W; Holliday, Gemma L; Steinbeck, Christoph; Thornton, Janet M

    2016-07-01

    Extracting chemical features like Atom-Atom Mapping (AAM), Bond Changes (BCs) and Reaction Centres from biochemical reactions helps us understand the chemical composition of enzymatic reactions. Reaction Decoder is a robust command line tool, which performs this task with high accuracy. It supports standard chemical input/output exchange formats i.e. RXN/SMILES, computes AAM, highlights BCs and creates images of the mapped reaction. This aids in the analysis of metabolic pathways and the ability to perform comparative studies of chemical reactions based on these features. This software is implemented in Java, supported on Windows, Linux and Mac OSX, and freely available at https://github.com/asad/ReactionDecoder : asad@ebi.ac.uk or s9asad@gmail.com. © The Author 2016. Published by Oxford University Press.

  2. DECODING OF ACADEMIC CONTENT BY THE 1st GRADE STUDENTS

    Directory of Open Access Journals (Sweden)

    Kamil Błaszczyński

    2017-07-01

    Full Text Available In the paper a comparative study conducted on the 1st grade students of sociology and pedagogy is discussed. The study was focused on the language skills of students. The most important skills tested were the abilities to decode academic content. The study shows that the students have very poor language skills in decoding the academic content on every level of its complexity. They also have noticeable problems with the definition of basic academic terms. The significance of the obtained results are high because of the innovative topic and character of the study, which was the first such study conducted on students of a Polish university. Results are also valuable for academic teachers who are interested in such problems as effective communication with students.

  3. Sonority and early words

    DEFF Research Database (Denmark)

    Kjærbæk, Laila; Boeg Thomsen, Ditte; Lambertsen, Claus

    2015-01-01

    Syllables play an important role in children’s early language acquisition, and children appear to rely on clear syllabic structures as a key to word acquisition (Vihman 1996; Oller 2000). However, not all languages present children with equally clear cues to syllabic structure, and since the spec......Syllables play an important role in children’s early language acquisition, and children appear to rely on clear syllabic structures as a key to word acquisition (Vihman 1996; Oller 2000). However, not all languages present children with equally clear cues to syllabic structure, and since...... acquisition therefore presents us with the opportunity to examine how children respond to the task of word learning when the input language offers less clear cues to syllabic structure than usually seen. To investigate the sound structure in Danish children’s lexical development, we need a model of syllable......-29 months. For the two children, the phonetic structure of the first ten words to occur is compared with that of the last ten words to occur before 30 months of age, and with that of ten words in between. Measures related to the sonority envelope, viz. sonority types and in particular sonority rises...

  4. Amyl: A Misunderstood Word

    Science.gov (United States)

    Kjonaas, Richard A.

    1996-12-01

    There is much confusion associated with the word amyl. For example, many textbooks draw a structural formula of n-pentyl acetate rather than isopentyl acetate when referring to the chief component of banana oil (amyl acetate). When younger chemists are taught to use the words propyl, butyl, and pentyl in place of n-propyl, n-butyl, and n-pentyl, they then incorrectly assume that this practice also applies to the word amyl. As is the case with banana oil, if the word amyl is going to be used to refer to just one of the isomeric pentyl groups, it should rightfully be isopentyl. The reason for this dates back to an abundant and important article of commerce called amylic alcohol (also called potato oil) which consisted chiefly of isopentyl alcohol. In fact, one can look in various chemical catalogs and handbooks of today and see such names as amyl benzoate and amyl nitrite used in place of isopentyl benzoate and isopentyl nitrite. Adding to all the confusion is the common practice of using the word amyl along with the singular form of another word when referring to an isomeric mixture; i.e. using amyl acetate rather than amyl acetates when referring to a mixture of pentyl acetates.

  5. Performance-complexity tradeoff in sequential decoding for the unconstrained AWGN channel

    KAUST Repository

    Abediseid, Walid

    2013-06-01

    In this paper, the performance limits and the computational complexity of the lattice sequential decoder are analyzed for the unconstrained additive white Gaussian noise channel. The performance analysis available in the literature for such a channel has been studied only under the use of the minimum Euclidean distance decoder that is commonly referred to as the lattice decoder. Lattice decoders based on solutions to the NP-hard closest vector problem are very complex to implement, and the search for low complexity receivers for the detection of lattice codes is considered a challenging problem. However, the low computational complexity advantage that sequential decoding promises, makes it an alternative solution to the lattice decoder. In this work, we characterize the performance and complexity tradeoff via the error exponent and the decoding complexity, respectively, of such a decoder as a function of the decoding parameter - the bias term. For the above channel, we derive the cut-off volume-to-noise ratio that is required to achieve a good error performance with low decoding complexity. © 2013 IEEE.

  6. Achievable Information Rates for Coded Modulation With Hard Decision Decoding for Coherent Fiber-Optic Systems

    Science.gov (United States)

    Sheikh, Alireza; Amat, Alexandre Graell i.; Liva, Gianluigi

    2017-12-01

    We analyze the achievable information rates (AIRs) for coded modulation schemes with QAM constellations with both bit-wise and symbol-wise decoders, corresponding to the case where a binary code is used in combination with a higher-order modulation using the bit-interleaved coded modulation (BICM) paradigm and to the case where a nonbinary code over a field matched to the constellation size is used, respectively. In particular, we consider hard decision decoding, which is the preferable option for fiber-optic communication systems where decoding complexity is a concern. Recently, Liga \\emph{et al.} analyzed the AIRs for bit-wise and symbol-wise decoders considering what the authors called \\emph{hard decision decoder} which, however, exploits \\emph{soft information} of the transition probabilities of discrete-input discrete-output channel resulting from the hard detection. As such, the complexity of the decoder is essentially the same as the complexity of a soft decision decoder. In this paper, we analyze instead the AIRs for the standard hard decision decoder, commonly used in practice, where the decoding is based on the Hamming distance metric. We show that if standard hard decision decoding is used, bit-wise decoders yield significantly higher AIRs than symbol-wise decoders. As a result, contrary to the conclusion by Liga \\emph{et al.}, binary decoders together with the BICM paradigm are preferable for spectrally-efficient fiber-optic systems. We also design binary and nonbinary staircase codes and show that, in agreement with the AIRs, binary codes yield better performance.

  7. STACK DECODING OF LINEAR BLOCK CODES FOR DISCRETE MEMORYLESS CHANNEL USING TREE DIAGRAM

    Directory of Open Access Journals (Sweden)

    H. Prashantha Kumar

    2012-03-01

    Full Text Available The boundaries between block and convolutional codes have become diffused after recent advances in the understanding of the trellis structure of block codes and the tail-biting structure of some convolutional codes. Therefore, decoding algorithms traditionally proposed for decoding convolutional codes have been applied for decoding certain classes of block codes. This paper presents the decoding of block codes using tree structure. Many good block codes are presently known. Several of them have been used in applications ranging from deep space communication to error control in storage systems. But the primary difficulty with applying Viterbi or BCJR algorithms to decode of block codes is that, even though they are optimum decoding methods, the promised bit error rates are not achieved in practice at data rates close to capacity. This is because the decoding effort is fixed and grows with block length, and thus only short block length codes can be used. Therefore, an important practical question is whether a suboptimal realizable soft decision decoding method can be found for block codes. A noteworthy result which provides a partial answer to this question is described in the following sections. This result of near optimum decoding will be used as motivation for the investigation of different soft decision decoding methods for linear block codes which can lead to the development of efficient decoding algorithms. The code tree can be treated as an expanded version of the trellis, where every path is totally distinct from every other path. We have derived the tree structure for (8, 4 and (16, 11 extended Hamming codes and have succeeded in implementing the soft decision stack algorithm to decode them. For the discrete memoryless channel, gains in excess of 1.5dB at a bit error rate of 10-5 with respect to conventional hard decision decoding are demonstrated for these codes.

  8. A Novel Modified Algorithm with Reduced Complexity LDPC Code Decoder

    OpenAIRE

    Song Yang; Bao Nanhai; Cai Chaoshi

    2014-01-01

    A novel efficient decoding algorithm reduced the sum-product algorithm (SPA) Complexity with LPDC code is proposed. Base on the hyperbolic tangent rule, modified the Check node update with two horizontal process, which have similar calculation, Motivated by the finding that sun- min (MS) algorithm reduce the complexity reducing the approximation error in the horizontal process, simplify the information weight small part. Compared with the exiting approximations, the proposed method is less co...

  9. Decoding material-specific memory reprocessing during sleep in humans

    OpenAIRE

    Sch?nauer, M.; Alizadeh, S.; Jamalabadi, H.; Abraham, A.; Pawlizki, A.; Gais, S.

    2017-01-01

    Neuronal learning activity is reactivated during sleep but the dynamics of this reactivation in humans are still poorly understood. Here we use multivariate pattern classification to decode electrical brain activity during sleep and determine what type of images participants had viewed in a preceding learning session. We find significant patterns of learning-related processing during rapid eye movement (REM) and non-REM (NREM) sleep, which are generalizable across subjects. This processing oc...

  10. Design and Implementation of Viterbi Decoder Using VHDL

    Science.gov (United States)

    Thakur, Akash; Chattopadhyay, Manju K.

    2018-03-01

    A digital design conversion of Viterbi decoder for ½ rate convolutional encoder with constraint length k = 3 is presented in this paper. The design is coded with the help of VHDL, simulated and synthesized using XILINX ISE 14.7. Synthesis results show a maximum frequency of operation for the design is 100.725 MHz. The requirement of memory is less as compared to conventional method.

  11. Reaction Decoder Tool (RDT): extracting features from chemical reactions

    OpenAIRE

    Rahman, Syed Asad; Torrance, Gilliean; Baldacci, Lorenzo; Mart?nez Cuesta, Sergio; Fenninger, Franz; Gopal, Nimish; Choudhary, Saket; May, John W.; Holliday, Gemma L.; Steinbeck, Christoph; Thornton, Janet M.

    2016-01-01

    Summary: Extracting chemical features like Atom?Atom Mapping (AAM), Bond Changes (BCs) and Reaction Centres from biochemical reactions helps us understand the chemical composition of enzymatic reactions. Reaction Decoder is a robust command line tool, which performs this task with high accuracy. It supports standard chemical input/output exchange formats i.e. RXN/SMILES, computes AAM, highlights BCs and creates images of the mapped reaction. This aids in the analysis of metabolic pathways and...

  12. Approximate MAP Decoding on Tail-Biting Trellises

    OpenAIRE

    Madhu, A. S.; Shankar, Priti

    2005-01-01

    We propose two approximate algorithms for MAP decoding on tail-biting trellises. The algorithms work on a subset of nodes of the tail-biting trellis, judiciously selected. We report the results of simulations on an AWGN channel using the approximate algorithms on tail-biting trellises for the $(24,12)$ Extended Golay Code and a rate 1/2 convolutional code with memory 6.

  13. Decoding Visual Object Categories in Early Somatosensory Cortex

    Science.gov (United States)

    Smith, Fraser W.; Goodale, Melvyn A.

    2015-01-01

    Neurons, even in the earliest sensory areas of cortex, are subject to a great deal of contextual influence from both within and across modality connections. In the present work, we investigated whether the earliest regions of somatosensory cortex (S1 and S2) would contain content-specific information about visual object categories. We reasoned that this might be possible due to the associations formed through experience that link different sensory aspects of a given object. Participants were presented with visual images of different object categories in 2 fMRI experiments. Multivariate pattern analysis revealed reliable decoding of familiar visual object category in bilateral S1 (i.e., postcentral gyri) and right S2. We further show that this decoding is observed for familiar but not unfamiliar visual objects in S1. In addition, whole-brain searchlight decoding analyses revealed several areas in the parietal lobe that could mediate the observed context effects between vision and somatosensation. These results demonstrate that even the first cortical stages of somatosensory processing carry information about the category of visually presented familiar objects. PMID:24122136

  14. Efficient algorithms for maximum likelihood decoding in the surface code

    Science.gov (United States)

    Bravyi, Sergey; Suchara, Martin; Vargo, Alexander

    2014-09-01

    We describe two implementations of the optimal error correction algorithm known as the maximum likelihood decoder (MLD) for the two-dimensional surface code with a noiseless syndrome extraction. First, we show how to implement MLD exactly in time O (n2), where n is the number of code qubits. Our implementation uses a reduction from MLD to simulation of matchgate quantum circuits. This reduction however requires a special noise model with independent bit-flip and phase-flip errors. Secondly, we show how to implement MLD approximately for more general noise models using matrix product states (MPS). Our implementation has running time O (nχ3), where χ is a parameter that controls the approximation precision. The key step of our algorithm, borrowed from the density matrix renormalization-group method, is a subroutine for contracting a tensor network on the two-dimensional grid. The subroutine uses MPS with a bond dimension χ to approximate the sequence of tensors arising in the course of contraction. We benchmark the MPS-based decoder against the standard minimum weight matching decoder observing a significant reduction of the logical error probability for χ ≥4.

  15. SWIPT in Multiuser MIMO Decode-and-Forward Relay Broadcasting Channel with Energy Harvesting Relays

    KAUST Repository

    Benkhelifa, Fatma

    2017-02-09

    In this paper, we consider a multiuser multiple- input multiple-output (MIMO) decode-and-forward (DF) relay broadcasting channel (BC) with single source, multiple energy harvesting relays and multiple destinations. Since the end-to-end sum rate maximization problem is intractable, we tackle a simplified problem where we maximize the sum of the harvested energy at the relays, we employ the block diagonalization (BD) procedure at the source, and we mitigate the interference between the relay- destination channels. The interference mitigation at the destinations is managed in two ways: either to fix the interference covariance matrices at the destination and update them at each iteration until convergence, or to cancel the interference using an algorithm similar to the BD method. We provide numerical results to show the relevance of our proposed solution.

  16. Sequential decoding of intramuscular EMG signals via estimation of a Markov model.

    Science.gov (United States)

    Monsifrot, Jonathan; Le Carpentier, Eric; Aoustin, Yannick; Farina, Dario

    2014-09-01

    This paper addresses the sequential decoding of intramuscular single-channel electromyographic (EMG) signals to extract the activity of individual motor neurons. A hidden Markov model is derived from the physiological generation of the EMG signal. The EMG signal is described as a sum of several action potentials (wavelet) trains, embedded in noise. For each train, the time interval between wavelets is modeled by a process that parameters are linked to the muscular activity. The parameters of this process are estimated sequentially by a Bayes filter, along with the firing instants. The method was tested on some simulated signals and an experimental one, from which the rates of detection and classification of action potentials were above 95% with respect to the reference decomposition. The method works sequentially in time, and is the first to address the problem of intramuscular EMG decomposition online. It has potential applications for man-machine interfacing based on motor neuron activities.

  17. Simple scheme for encoding and decoding a qubit in unknown state for various topological codes

    Science.gov (United States)

    Łodyga, Justyna; Mazurek, Paweł; Grudka, Andrzej; Horodecki, Michał

    2015-03-01

    We present a scheme for encoding and decoding an unknown state for CSS codes, based on syndrome measurements. We illustrate our method by means of Kitaev toric code, defected-lattice code, topological subsystem code and 3D Haah code. The protocol is local whenever in a given code the crossings between the logical operators consist of next neighbour pairs, which holds for the above codes. For subsystem code we also present scheme in a noisy case, where we allow for bit and phase-flip errors on qubits as well as state preparation and syndrome measurement errors. Similar scheme can be built for two other codes. We show that the fidelity of the protected qubit in the noisy scenario in a large code size limit is of , where p is a probability of error on a single qubit per time step. Regarding Haah code we provide noiseless scheme, leaving the noisy case as an open problem.

  18. The influence of social, individual and linguistic factors on children's performance in tasks of reading single words aloud / A Influência de fatores sociais, individuais e lingüísticos no desempenho de crianças na leitura em voz alta de palavras isoladas

    Directory of Open Access Journals (Sweden)

    Patrícia Silva Lúcio

    2010-01-01

    Full Text Available This study evaluates social, individual and linguistic factors in the performance of a single- word reading aloud task. A group of 1st to 4th grade school children from Belo Horizonte-MG (N = 333 read aloud 323 single words presented in a computer screen. Measures of reaction time (RT and error scores were collected. The Generalized Estimating Equations method exhibited the grapheme-phoneme and phoneme-grapheme regularity effect in reading and also showed an impact on the number of categories of regularity in this effect. No social factor was important to explain the results, but their mothers' education was correlated to the error scores (in opposite direction. There was no gender effect. Other factors rather than the traditional ones were also relevant, such as the age of reading acquisition and the verbal comprehension. The work brings important theoretical issues to cognitive reading assessment in Brazil.

  19. Phonological Awareness and Word Recognition in Reading by Children with Autism

    Science.gov (United States)

    Gabig, Cheryl Smith

    2010-01-01

    This research examined phonological awareness (PA) and single word reading in 14 school-age children with autism and 10 age-matched, typically developing (TD) children between 5-7 years. Two measures of PA, an elision task (ELI) and a sound blending task (BLW), were given along with two measures of single word reading, word identification for real…

  20. Reading visually embodied meaning from the brain: Visually grounded computational models decode visual-object mental imagery induced by written text.

    Science.gov (United States)

    Anderson, Andrew James; Bruni, Elia; Lopopolo, Alessandro; Poesio, Massimo; Baroni, Marco

    2015-10-15

    Embodiment theory predicts that mental imagery of object words recruits neural circuits involved in object perception. The degree of visual imagery present in routine thought and how it is encoded in the brain is largely unknown. We test whether fMRI activity patterns elicited by participants reading objects' names include embodied visual-object representations, and whether we can decode the representations using novel computational image-based semantic models. We first apply the image models in conjunction with text-based semantic models to test predictions of visual-specificity of semantic representations in different brain regions. Representational similarity analysis confirms that fMRI structure within ventral-temporal and lateral-occipital regions correlates most strongly with the image models and conversely text models correlate better with posterior-parietal/lateral-temporal/inferior-frontal regions. We use an unsupervised decoding algorithm that exploits commonalities in representational similarity structure found within both image model and brain data sets to classify embodied visual representations with high accuracy (8/10) and then extend it to exploit model combinations to robustly decode different brain regions in parallel. By capturing latent visual-semantic structure our models provide a route into analyzing neural representations derived from past perceptual experience rather than stimulus-driven brain activity. Our results also verify the benefit of combining multimodal data to model human-like semantic representations. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. WORD LEVEL DISCRIMINATIVE TRAINING FOR HANDWRITTEN WORD RECOGNITION

    NARCIS (Netherlands)

    Chen, W.; Gader, P.

    2004-01-01

    Word level training refers to the process of learning the parameters of a word recognition system based on word level criteria functions. Previously, researchers trained lexicon­driven handwritten word recognition systems at the character level individually. These systems generally use statistical

  2. Audio Signal Decoder, Method for Decoding an Audio Signal and Computer Program Using Cascaded Audio Object Processing Stages

    OpenAIRE

    Hellmuth, O.; Falch, C.; Herre, J.; Hilpert, J.; Ridderbusch, F.; Terentiev, L.

    2010-01-01

    An audio signal decoder for providing an upmix signal representation in dependence on a downmix signal representation and an object-related parametric information comprises an object separator configured to decompose the downmix signal representation, to provide a first audio information describing a first set of one or more audio objects of a first audio object type and a second audio information describing a second set of one or more audio objects of a second audio object type, in dependenc...

  3. Replicability of sight word training and phonics training in poor readers: a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    G McArthur

    2015-05-01

    Full Text Available Given the importance of effective treatments for children with reading impairment, paired with growing concern about the lack of scientific replication in psychological science, the aim of this study was to replicate a quasi-randomised trial of sight word and phonics training using a randomised controlled trial (RCT design. One group of poor readers (N = 41 did 8 weeks of phonics training (i.e., phonological decoding and then 8 weeks of sight word training (i.e., whole-word recognition. A second group did the reverse order of training. Sight word and phonics training each had a large and significant valid treatment effect on trained irregular words and word reading fluency. In addition, combined sight word and phonics training had a moderate and significant valid treatment effect on nonword reading accuracy and fluency. These findings demonstrate the reliability of both phonics and sight word training in treating poor readers in an era where the importance of scientific reliability is under close scrutiny.

  4. On the Properties of Neural Machine Translation: Encoder-Decoder Approaches

    OpenAIRE

    Cho, Kyunghyun; van Merrienboer, Bart; Bahdanau, Dzmitry; Bengio, Yoshua

    2014-01-01

    Neural machine translation is a relatively new approach to statistical machine translation based purely on neural networks. The neural machine translation models often consist of an encoder and a decoder. The encoder extracts a fixed-length representation from a variable-length input sentence, and the decoder generates a correct translation from this representation. In this paper, we focus on analyzing the properties of the neural machine translation using two models; RNN Encoder--Decoder and...

  5. Design of optical decoders using a polarization-encoded optical shadow-casting scheme

    Science.gov (United States)

    Rizvi, Rizwan A.; Zaheer, K.; Zubairy, M. Zuhail

    1988-12-01

    The design of various decoders in the polarization-encoded optical shadow-casting scheme is presented. A general algorithm is used to design these multioutput combinational logic units with separate and simultaneous generation of outputs. In particular, the design of a binary coded decimal (BCD) to an Octal decoder and a BCD to an Excess-3 converter is presented for a fixed source plane as well as a fixed decoding mask. The results have been verified experimentally.

  6. Neural overlap of L1 and L2 semantic representations in speech: A decoding approach.

    Science.gov (United States)

    Van de Putte, Eowyn; De Baene, Wouter; Brass, Marcel; Duyck, Wouter

    2017-11-15

    Although research has now converged towards a consensus that both languages of a bilingual are represented in at least partly shared systems for language comprehension, it remains unclear whether both languages are represented in the same neural populations for production. We investigated the neural overlap between L1 and L2 semantic representations of translation equivalents using a production task in which the participants had to name pictures in L1 and L2. Using a decoding approach, we tested whether brain activity during the production of individual nouns in one language allowed predicting the production of the same concepts in the other language. Because both languages only share the underlying semantic representation (sensory and lexical overlap was maximally avoided), this would offer very strong evidence for neural overlap in semantic representations of bilinguals. Based on the brain activation for the individual concepts in one language in the bilateral occipito-temporal cortex and the inferior and the middle temporal gyrus, we could accurately predict the equivalent individual concepts in the other language. This indicates that these regions share semantic representations across L1 and L2 word production. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. "Decoding versus comprehension": Brain responses underlying reading comprehension in children with autism.

    Science.gov (United States)

    Bednarz, Haley M; Maximo, Jose O; Murdaugh, Donna L; O'Kelley, Sarah; Kana, Rajesh K

    2017-06-01

    Despite intact decoding ability, deficits in reading comprehension are relatively common in children with autism spectrum disorders (ASD). However, few neuroimaging studies have tested the neural bases of this specific profile of reading deficit in ASD. This fMRI study examined activation and synchronization of the brain's reading network in children with ASD with specific reading comprehension deficits during a word similarities task. Thirteen typically developing children and 18 children with ASD performed the task in the MRI scanner. No statistically significant group differences in functional activation were observed; however, children with ASD showed decreased functional connectivity between the left inferior frontal gyrus (LIFG) and the left inferior occipital gyrus (LIOG). In addition, reading comprehension ability significantly positively predicted functional connectivity between the LIFG and left thalamus (LTHAL) among all subjects. The results of this study provide evidence for altered recruitment of reading-related neural resources in ASD children and suggest specific weaknesses in top-down modulation of semantic processing. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. The Activation of Embedded Words in Spoken Word Recognition

    Science.gov (United States)

    Zhang, Xujin; Samuel, Arthur G.

    2015-01-01

    The current study investigated how listeners understand English words that have shorter words embedded in them. A series of auditory-auditory priming experiments assessed the activation of six types of embedded words (2 embedded positions × 3 embedded proportions) under different listening conditions. Facilitation of lexical decision responses to targets (e.g., pig) associated with words embedded in primes (e.g., hamster) indexed activation of the embedded words (e.g., ham). When the listening conditions were optimal, isolated embedded words (e.g., ham) primed their targets in all six conditions (Experiment 1a). Within carrier words (e.g., hamster), the same set of embedded words produced priming only when they were at the beginning or comprised a large proportion of the carrier word (Experiment 1b). When the listening conditions were made suboptimal by expanding or compressing the primes, significant priming was found for isolated embedded words (Experiment 2a), but no priming was produced when the carrier words were compressed/expanded (Experiment 2b). Similarly, priming was eliminated when the carrier words were presented with one segment replaced by noise (Experiment 3). When cognitive load was imposed, priming for embedded words was again found when they were presented in isolation (Experiment 4a), but not when they were embedded in the carrier words (Experiment 4b). The results suggest that both embedded position and proportion play important roles in the activation of embedded words, but that such activation only occurs under unusually good listening conditions. PMID:25593407

  9. Reduplication Facilitates Early Word Segmentation

    Science.gov (United States)

    Ota, Mitsuhiko; Skarabela, Barbora

    2018-01-01

    This study explores the possibility that early word segmentation is aided by infants' tendency to segment words with repeated syllables ("reduplication"). Twenty-four nine-month-olds were familiarized with passages containing one novel reduplicated word and one novel non-reduplicated word. Their central fixation times in response to…

  10. Essential words for the TOEFL

    CERN Document Server

    Matthiesen, Steven J

    2017-01-01

    This revised book is specifically designed for ESL students preparing to take the TOEFL. Includes new words and phrases, a section on purpose words, a list of vocabulary words with definitions, sample sentences, practice exercises for 500 need-to-know words, practice test with answer key, and more.

  11. The Effectiveness of Dictionary Examples in Decoding: The Case of Kuwaiti Learners of English

    Directory of Open Access Journals (Sweden)

    Hashan Al-Ajmi

    2011-10-01

    Full Text Available

    Abstract: This study tries to shed light on the role of dictionary examples in the comprehension of word meanings. An experimental procedure has been devised whereby two groups of students with English as major subject at Kuwait University were asked to provide the Arabic equivalents for ten English headwords. The first group was given a list of entries for these words copied from the Oxford Advanced Learner's Dictionary (OALD while the second group had to read the same list but without illustrative examples. Results indicate that the students' decoding performance was negatively affected by the presence of illustrative examples in the dictionary entry.

    Keywords: ARABIC, BILINGUAL DICTIONARY, COMPREHENSION, EFL DICTIONARY,ILLUSTRATIVE EXAMPLE, MONOLINGUAL DICTIONARY, TRANSLATION

    Opsomming: Die doeltreffendheid van woordeboekvoorbeelde by dekodering:Die geval van Koeweiti-aanleerders van Engels. Hierdie studie probeer ligwerp op die rol van woordeboekvoorbeelde by die verstaan van woordbetekenisse. 'n Eksperimentelemetode is ontwerp waarby twee groepe studente met Engels as hoofvak by die Universiteit vanKoeweit gevra is om Arabiese ekwivalente vir tien Engelse trefwoorde te verskaf. Aan die eerstegroep is 'n lys inskrywings van hierdie woorde oorgeneem uit die Oxford Advanced Learner's Dictionary(OALD gegee, terwyl die tweede groep dieselfde lys moes lees, maar sonder verduidelikendevoorbeelde. Resultate het aangedui dat die studente se dekoderende prestasie negatiefbeïnvloed is deur die teenwoordigheid van verduidelikende voorbeelde in die woordeboekinskrywing.

    Sleutelwoorde: ARABIES, TWEETALIGE WOORDEBOEK, BEGRIP, EVT-WOORDEBOEK,VERDUIDELIKENDE VOORBEELD, EENTALIGE WOORDEBOEK, VERTALING

  12. AARP Word 2010 for dummies

    CERN Document Server

    Gookin, Dan

    2011-01-01

    It's a whole new Word - make the most of it! Here's exactly what you need to know to get going with Word 2010. From firing up Word, using the spell checker, and working with templates to formatting documents, adding images, and saving your stuff, you'll get the first and last word on Word 2010 with this fun and easy mini guide. So get ready to channel your inner writer and start creating Word files that wow! Open the book and find:Tips for navigating Word with the keyboard and mouseAdvice on using the RibbonHow to edit text and undo mistakesThings to know

  13. Firing rate estimation using infinite mixture models and its application to neural decoding.

    Science.gov (United States)

    Shibue, Ryohei; Komaki, Fumiyasu

    2017-11-01

    Neural decoding is a framework for reconstructing external stimuli from spike trains recorded by various neural recordings. Kloosterman et al. proposed a new decoding method using marked point processes (Kloosterman F, Layton SP, Chen Z, Wilson MA. J Neurophysiol 111: 217-227, 2014). This method does not require spike sorting and thereby improves decoding accuracy dramatically. In this method, they used kernel density estimation to estimate intensity functions of marked point processes. However, the use of kernel density estimation causes problems such as low decoding accuracy and high computational costs. To overcome these problems, we propose a new decoding method using infinite mixture models to estimate intensity. The proposed method improves decoding performance in terms of accuracy and computational speed. We apply the proposed method to simulation and experimental data to verify its performance. NEW & NOTEWORTHY We propose a new neural decoding method using infinite mixture models and nonparametric Bayesian statistics. The proposed method improves decoding performance in terms of accuracy and computation speed. We have successfully applied the proposed method to position decoding from spike trains recorded in a rat hippocampus. Copyright © 2017 the American Physiological Society.

  14. A model for sequential decoding overflow due to a noisy carrier reference. [communication performance prediction

    Science.gov (United States)

    Layland, J. W.

    1974-01-01

    An approximate analysis of the effect of a noisy carrier reference on the performance of sequential decoding is presented. The analysis uses previously developed techniques for evaluating noisy reference performance for medium-rate uncoded communications adapted to sequential decoding for data rates of 8 to 2048 bits/s. In estimating the ten to the minus fourth power deletion probability thresholds for Helios, the model agrees with experimental data to within the experimental tolerances. The computational problem involved in sequential decoding, carrier loop effects, the main characteristics of the medium-rate model, modeled decoding performance, and perspectives on future work are discussed.

  15. Convergence Analysis of Turbo Decoding of Serially Concatenated Block Codes and Product Codes

    Directory of Open Access Journals (Sweden)

    Krause Amir

    2005-01-01

    Full Text Available The geometric interpretation of turbo decoding has founded a framework, and provided tools for the analysis of parallel-concatenated codes decoding. In this paper, we extend this analytical basis for the decoding of serially concatenated codes, and focus on serially concatenated product codes (SCPC (i.e., product codes with checks on checks. For this case, at least one of the component (i.e., rows/columns decoders should calculate the extrinsic information not only for the information bits, but also for the check bits. We refer to such a component decoder as a serial decoding module (SDM. We extend the framework accordingly, derive the update equations for a general turbo decoder of SCPC, and the expressions for the main analysis tools: the Jacobian and stability matrices. We explore the stability of the SDM. Specifically, for high SNR, we prove that the maximal eigenvalue of the SDM's stability matrix approaches , where is the minimum Hamming distance of the component code. Hence, for practical codes, the SDM is unstable. Further, we analyze the two turbo decoding schemes, proposed by Benedetto and Pyndiah, by deriving the corresponding update equations and by demonstrating the structure of their stability matrices for the repetition code and an SCPC code with information bits. Simulation results for the Hamming and Golay codes are presented, analyzed, and compared to the theoretical results and to simulations of turbo decoding of parallel concatenation of the same codes.

  16. Multiple-Symbol Noncoherent Decoding of Uncoded and Convolutionally Codes Continous Phase Modulation

    Science.gov (United States)

    Divsalar, D.; Raphaeli, D.

    2000-01-01

    Recently, a method for combined noncoherent detection and decoding of trellis-codes (noncoherent coded modulation) has been proposed, which can practically approach the performance of coherent detection.

  17. VLSI Architectures for Sliding-Window-Based Space-Time Turbo Trellis Code Decoders

    Directory of Open Access Journals (Sweden)

    Georgios Passas

    2012-01-01

    Full Text Available The VLSI implementation of SISO-MAP decoders used for traditional iterative turbo coding has been investigated in the literature. In this paper, a complete architectural model of a space-time turbo code receiver that includes elementary decoders is presented. These architectures are based on newly proposed building blocks such as a recursive add-compare-select-offset (ACSO unit, A-, B-, Γ-, and LLR output calculation modules. Measurements of complexity and decoding delay of several sliding-window-technique-based MAP decoder architectures and a proposed parameter set lead to defining equations and comparison between those architectures.

  18. Bouyei word formation

    Directory of Open Access Journals (Sweden)

    Attasith Boonsawasd

    2012-12-01

    Full Text Available The Bouyei language is divided into three vernaculars, the southern vernacular, the central vernacular and the southwestern vernacular. This paper aims to describe the lexicology of the southern vernacular of the Bouyei language focusing on word formation process. Bouyei words are formed by affixing, compounding and reduplicating. First, the affixation consists of prefixing and suffixing. Infixing is not found in this language. Second, the compound is divided into the semantic and syntactic compound. Finally, the reduplication is divided into the simple and complex reduplication. The simple reduplication is normally used to emphasize the meaning of the root or to indicate plurality.

  19. Evidence for simultaneous syntactic processing of multiple words during reading.

    Directory of Open Access Journals (Sweden)

    Joshua Snell

    Full Text Available A hotly debated issue in reading research concerns the extent to which readers process parafoveal words, and how parafoveal information might influence foveal word recognition. We investigated syntactic word processing both in sentence reading and in reading isolated foveal words when these were flanked by parafoveal words. In Experiment 1 we found a syntactic parafoveal preview benefit in sentence reading, meaning that fixation durations on target words were decreased when there was a syntactically congruent preview word at the target location (n during the fixation on the pre-target (n-1. In Experiment 2 we used a flanker paradigm in which participants had to classify foveal target words as either noun or verb, when those targets were flanked by syntactically congruent or incongruent words (stimulus on-time 170 ms. Lower response times and error rates in the congruent condition suggested that higher-order (syntactic information can be integrated across foveal and parafoveal words. Although higher-order parafoveal-on-foveal effects have been elusive in sentence reading, results from our flanker paradigm show that the reading system can extract higher-order information from multiple words in a single glance. We propose a model of reading to account for the present findings.

  20. Homotopy invariants of Gauss words

    OpenAIRE

    Gibson, Andrew

    2009-01-01

    By defining combinatorial moves, we can define an equivalence relation on Gauss words called homotopy. In this paper we define a homotopy invariant of Gauss words. We use this to show that there exist Gauss words that are not homotopically equivalent to the empty Gauss word, disproving a conjecture by Turaev. In fact, we show that there are an infinite number of equivalence classes of Gauss words under homotopy.

  1. Using Constant Time Delay to Teach Braille Word Recognition

    Science.gov (United States)

    Hooper, Jonathan; Ivy, Sarah; Hatton, Deborah

    2014-01-01

    Introduction: Constant time delay has been identified as an evidence-based practice to teach print sight words and picture recognition (Browder, Ahlbrim-Delzell, Spooner, Mims, & Baker, 2009). For the study presented here, we tested the effectiveness of constant time delay to teach new braille words. Methods: A single-subject multiple baseline…

  2. Translation Ambiguity but Not Word Class Predicts Translation Performance

    Science.gov (United States)

    Prior, Anat; Kroll, Judith F.; Macwhinney, Brian

    2013-01-01

    We investigated the influence of word class and translation ambiguity on cross-linguistic representation and processing. Bilingual speakers of English and Spanish performed translation production and translation recognition tasks on nouns and verbs in both languages. Words either had a single translation or more than one translation. Translation…

  3. Offensive Words, Lethal Weapons

    Science.gov (United States)

    Jacoby, Russell

    2007-01-01

    The old childhood ditty "sticks and stones may break my bones, but words will never hurt me" has proved wiser than the avalanche of commentary provoked by the recent insults by Don Imus and the killings at Virginia Tech. Our society forbids public name-calling but allows sticks and stones. Anyone can acquire a gun, but everyone must be…

  4. Getting the Word Out.

    Science.gov (United States)

    Brandou, Julian R.

    1982-01-01

    Suggests public relations strategies which science educators can adopt to spread the word about the importance of good science teaching. These include preparing a fact sheet summarizing a project/course/organization, tips on creating a newsworthy event (awards, displays at a mall, and others), and what to submit to the news media. (Author/JN)

  5. Doing words together

    DEFF Research Database (Denmark)

    Fusaroli, Riccardo; Østergaard, Svend; Raczaszek-Leonardi, Joanna

    In this paper we test the effects of social interactions in embodied problem solving by employing a Scrabble-like setting. 28 pairs of participants had to generate as many words as possible from 2 balanced sets of 7 letters, which they could manipulate, either individually or collectively...

  6. Italian Word Association Norms.

    Science.gov (United States)

    1966-07-01

    Ricerche Istituto Nazionale I Psicologia , Roma Italy. A different, but not unrelated, approach is to use word association norms to study other types of... Psicologia , 1961 , 55, 1,13-155. Chiari, S. 11 comportamento associative nell’eta ovolutiva, Rivista di Psicologia , 1 96 1b , 55, 175-189. Cofer, C.N

  7. A Life in Words

    DEFF Research Database (Denmark)

    Siegumfeldt, Inge Birgitte; Auster, Paul

    "Paul Auster's A Life in Words--a wide-ranging dialogue between Auster and the Danish professor I.B. Siegumfeldt--is a remarkably candid and often surprising celebration of one writer's art, craft, and life. It includes many revelations that have never been shared before, such as that he doesn...

  8. Have Words, Will Understand?

    Science.gov (United States)

    James, Jon

    2013-01-01

    Shifting the focus from words to concepts--does it work? The author shares his findings from such a project with three primary schools in the UK. Many children aged 7-10 find mastering the language of science difficult and do not make the progress that they could. Encountering complex terminology in the science language causes students to become…

  9. Children's First Word Combinations

    Science.gov (United States)

    Braine, Martin D. S.

    1976-01-01

    This monograph presents a descriptive analysis of the syntactic patterns in 16 corpora of word combinations from 11 infants learning either English (six children), Samoan, Finnish, Hebrew, or Swedish. The mean utterance lengths range up to about 1.7 morpehmes. There are both reanalyses of corpora in the literature and new corpora. The data…

  10. Negative feedback governs gonadotrope frequency-decoding of gonadotropin releasing hormone pulse-frequency.

    Directory of Open Access Journals (Sweden)

    Stefan Lim

    Full Text Available The synthesis of the gonadotropin subunits is directed by pulsatile gonadotropin-releasing hormone (GnRH from the hypothalamus, with the frequency of GnRH pulses governing the differential expression of the common alpha-subunit, luteinizing hormone beta-subunit (LHbeta and follicle-stimulating hormone beta-subunit (FSHbeta. Three mitogen-activated protein kinases, (MAPKs, ERK1/2, JNK and p38, contribute uniquely and combinatorially to the expression of each of these subunit genes. In this study, using both experimental and computational methods, we found that dual specificity phosphatase regulation of the activity of the three MAPKs through negative feedback is required, and forms the basis for decoding the frequency of pulsatile GnRH. A fourth MAPK, ERK5, was shown also to be activated by GnRH. ERK5 was found to stimulate FSHbeta promoter activity and to increase FSHbeta mRNA levels, as well as enhancing its preference for low GnRH pulse frequencies. The latter is achieved through boosting the ultrasensitive behavior of FSHbeta gene expression by increasing the number of MAPK dependencies, and through modulating the feedforward effects of JNK activation on the GnRH receptor (GnRH-R. Our findings contribute to understanding the role of changing GnRH pulse-frequency in controlling transcription of the pituitary gonadotropins, which comprises a crucial aspect in regulating reproduction. Pulsatile stimuli and oscillating signals are integral to many biological processes, and elucidation of the mechanisms through which the pulsatility is decoded explains how the same stimulant can lead to various outcomes in a single cell.

  11. An Improved Unscented Kalman Filter Based Decoder for Cortical Brain-Machine Interfaces.

    Science.gov (United States)

    Li, Simin; Li, Jie; Li, Zheng

    2016-01-01

    Brain-machine interfaces (BMIs) seek to connect brains with machines or computers directly, for application in areas such as prosthesis control. For this application, the accuracy of the decoding of movement intentions is crucial. We aim to improve accuracy by designing a better encoding model of primary motor cortical activity during hand movements and combining this with decoder engineering refinements, resulting in a new unscented Kalman filter based decoder, UKF2, which improves upon our previous unscented Kalman filter decoder, UKF1. The new encoding model includes novel acceleration magnitude, position-velocity interaction, and target-cursor-distance features (the decoder does not require target position as input, it is decoded). We add a novel probabilistic velocity threshold to better determine the user's intent to move. We combine these improvements with several other refinements suggested by others in the field. Data from two Rhesus monkeys indicate that the UKF2 generates offline reconstructions of hand movements (mean CC 0.851) significantly more accurately than the UKF1 (0.833) and the popular position-velocity Kalman filter (0.812). The encoding model of the UKF2 could predict the instantaneous firing rate of neurons (mean CC 0.210), given kinematic variables and past spiking, better than the encoding models of these two decoders (UKF1: 0.138, p-v Kalman: 0.098). In closed-loop experiments where each monkey controlled a computer cursor with each decoder in turn, the UKF2 facilitated faster task completion (mean 1.56 s vs. 2.05 s) and higher Fitts's Law bit rate (mean 0.738 bit/s vs. 0.584 bit/s) than the UKF1. These results suggest that the modeling and decoder engineering refinements of the UKF2 improve decoding performance. We believe they can be used to enhance other decoders as well.

  12. A Novel Modified Algorithm with Reduced Complexity LDPC Code Decoder

    Directory of Open Access Journals (Sweden)

    Song Yang

    2014-10-01

    Full Text Available A novel efficient decoding algorithm reduced the sum-product algorithm (SPA Complexity with LPDC code is proposed. Base on the hyperbolic tangent rule, modified the Check node update with two horizontal process, which have similar calculation, Motivated by the finding that sun- min (MS algorithm reduce the complexity reducing the approximation error in the horizontal process, simplify the information weight small part. Compared with the exiting approximations, the proposed method is less computational complexity than SPA algorithm. Simulation results show that the author algorithm can achieve performance very close SPA.

  13. Multiple LDPC decoding for distributed source coding and video coding

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Luong, Huynh Van; Huang, Xin

    2011-01-01

    Distributed source coding (DSC) is a coding paradigm for systems which fully or partly exploit the source statistics at the decoder to reduce the computational burden at the encoder. Distributed video coding (DVC) is one example. This paper considers the use of Low Density Parity Check Accumulate...... results on DVC show that the LDPCA perfomance implies a loss compared to the conditional entropy, but also that the proposed scheme reduces the DVC bit rate up to 3.9% and improves the rate-distortion (RD) performance of a Transform Domain Wyner-Ziv (TDWZ) video codec....

  14. Construction and decoding of a class of algebraic geometry codes

    DEFF Research Database (Denmark)

    Justesen, Jørn; Larsen, Knud J.; Jensen, Helge Elbrønd

    1989-01-01

    A class of codes derived from algebraic plane curves is constructed. The concepts and results from algebraic geometry that were used are explained in detail; no further knowledge of algebraic geometry is needed. Parameters, generator and parity-check matrices are given. The main result is a decod......A class of codes derived from algebraic plane curves is constructed. The concepts and results from algebraic geometry that were used are explained in detail; no further knowledge of algebraic geometry is needed. Parameters, generator and parity-check matrices are given. The main result...

  15. Decoding the auditory brain with canonical component analysis

    DEFF Research Database (Denmark)

    de Cheveigné, Alain; Wong, Daniel D E; Di Liberto, Giovanni M

    2018-01-01

    The relation between a stimulus and the evoked brain response can shed light on perceptual processes within the brain. Signals derived from this relation can also be harnessed to control external devices for Brain Computer Interface (BCI) applications. While the classic event-related potential (ERP......) is appropriate for isolated stimuli, more sophisticated "decoding" strategies are needed to address continuous stimuli such as speech, music or environmental sounds. Here we describe an approach based on Canonical Correlation Analysis (CCA) that finds the optimal transform to apply to both the stimulus...

  16. Synthesizer for decoding a coded short wave length irradiation

    International Nuclear Information System (INIS)

    1976-01-01

    The system uses point irradiation source, typically an X-ray emitter, which illuminates a three dimensional object consisting of a set of parallel planes, each of which acts as a source of coded information. The secondary source images are superimposed on a common flat screen. The decoding system comprises an imput light-screen detector, a picture screen amplifier, a beam deflector, on output picture screen, an optical focussing unit including three lenses, a masking unit, an output light screen detector and a video signal reproduction unit of cathode ray tube from, or similar, to create a three dimensional image of the object. (G.C.)

  17. Decoding the organization of spinal circuits that control locomotion

    Science.gov (United States)

    Kiehn, Ole

    2016-01-01

    Unravelling the functional operation of neuronal networks and linking cellular activity to specific behavioural outcomes are among the biggest challenges in neuroscience. In this broad field of research, substantial progress has been made in studies of the spinal networks that control locomotion. Through united efforts using electrophysiological and molecular genetic network approaches and behavioural studies in phylogenetically diverse experimental models, the organization of locomotor networks has begun to be decoded. The emergent themes from this research are that the locomotor networks have a modular organization with distinct transmitter and molecular codes and that their organization is reconfigured with changes to the speed of locomotion or changes in gait. PMID:26935168

  18. Single-item memory, associative memory, and the human hippocampus

    OpenAIRE

    Gold, Jeffrey J.; Hopkins, Ramona O.; Squire, Larry R.

    2006-01-01

    We tested recognition memory for items and associations in memory-impaired patients with bilateral lesions thought to be limited to the hippocampal region. In Experiment 1 (Combined memory test), participants studied words and then took a memory test in which studied words, new words, studied word pairs, and recombined word pairs were presented in a mixed order. In Experiment 2 (Separated memory test), participants studied single words and then took a memory test involving studied word and ne...

  19. The Word Superiority Effect in central and peripheral vision

    DEFF Research Database (Denmark)

    Sand, Katrine; Habekost, Thomas; Petersen, Anders

    2016-01-01

    The Word Superiority Effect (WSE) is a well-known phenomenon in reading research, where words are reported more accurately than single letters or non-words. We report two experiments that investigate the WSE in the central and peripheral visual field, as well as laterality differences...... in the perception of words and letters, using methods based on the Theory of Visual Attention. The results show a WSE in the central visual field, reflected in mean scores, perception thresholds, and processing speed, whereas the effect is eliminated or reversed in the periphery. This may be caused by crowding......, which prevents lexical analysis of a word in the periphery. We conclude that perception of words and letters differs according to location in the visual field. Linking our results to previous studies of crowding effects in patients with reading impairments, we hypothesize that similar mechanisms may...

  20. Role of syllable segmentation processes in peripheral word recognition.

    Science.gov (United States)

    Bernard, Jean-Baptiste; Calabrèse, Aurélie; Castet, Eric

    2014-12-01

    Previous studies of foveal visual word recognition provide evidence for a low-level syllable decomposition mechanism occurring during the recognition of a word. We investigated if such a decomposition mechanism also exists in peripheral word recognition. Single words were visually presented to subjects in the peripheral field using a 6° square gaze-contingent simulated central scotoma. In the first experiment, words were either unicolor or had their adjacent syllables segmented with two different colors (color/syllable congruent condition). Reaction times for correct word identification were measured for the two different conditions and for two different print sizes. Results show a significant decrease in reaction time for the color/syllable congruent condition compared with the unicolor condition. A second experiment suggests that this effect is specific to syllable decomposition and results from strategic, presumably involving attentional factors, rather than stimulus-driven control.

  1. Right word making sense of the words that confuse

    CERN Document Server

    Morrison, Elizabeth

    2012-01-01

    'Affect' or 'effect'? 'Right', 'write' or 'rite'? English can certainly be a confusing language, whether you're a native speaker or learning it as a second language. 'The Right Word' is the essential reference to help people master its subtleties and avoid making mistakes. Divided into three sections, it first examines homophones - those tricky words that sound the same but are spelled differently - then looks at words that often confuse before providing a list of commonly misspelled words.

  2. Application of source biasing technique for energy efficient DECODER circuit design: memory array application

    Science.gov (United States)

    Gupta, Neha; Parihar, Priyanka; Neema, Vaibhav

    2018-04-01

    Researchers have proposed many circuit techniques to reduce leakage power dissipation in memory cells. If we want to reduce the overall power in the memory system, we have to work on the input circuitry of memory architecture i.e. row and column decoder. In this research work, low leakage power with a high speed row and column decoder for memory array application is designed and four new techniques are proposed. In this work, the comparison of cluster DECODER, body bias DECODER, source bias DECODER, and source coupling DECODER are designed and analyzed for memory array application. Simulation is performed for the comparative analysis of different DECODER design parameters at 180 nm GPDK technology file using the CADENCE tool. Simulation results show that the proposed source bias DECODER circuit technique decreases the leakage current by 99.92% and static energy by 99.92% at a supply voltage of 1.2 V. The proposed circuit also improves dynamic power dissipation by 5.69%, dynamic PDP/EDP 65.03% and delay 57.25% at 1.2 V supply voltage.

  3. Multi-Trial Guruswami–Sudan Decoding for Generalised Reed–Solomon Codes

    DEFF Research Database (Denmark)

    Nielsen, Johan Sebastian Rosenkilde; Zeh, Alexander

    2013-01-01

    An iterated refinement procedure for the Guruswami–Sudan list decoding algorithm for Generalised Reed–Solomon codes based on Alekhnovich’s module minimisation is proposed. The method is parametrisable and allows variants of the usual list decoding approach. In particular, finding the list...

  4. Using convolutional decoding to improve time delay and phase estimation in digital communications

    Science.gov (United States)

    Ormesher, Richard C [Albuquerque, NM; Mason, John J [Albuquerque, NM

    2010-01-26

    The time delay and/or phase of a communication signal received by a digital communication receiver can be estimated based on a convolutional decoding operation that the communication receiver performs on the received communication signal. If the original transmitted communication signal has been spread according to a spreading operation, a corresponding despreading operation can be integrated into the convolutional decoding operation.

  5. Mutiple LDPC Decoding using Bitplane Correlation for Transform Domain Wyner-Ziv Video Coding

    DEFF Research Database (Denmark)

    Luong, Huynh Van; Huang, Xin; Forchhammer, Søren

    2011-01-01

    codec. To improve the LDPC coding performance in the context of TDWZ, this paper proposes a Wyner-Ziv video codec using bitplane correlation through multiple parallel LDPC decoding. The proposed scheme utilizes inter bitplane correlation to enhance the bitplane decoding performance. Experimental results...

  6. Prior Knowledge of Target Direction and Intended Movement Selection Improves Indirect Reaching Movement Decoding.

    Science.gov (United States)

    Li, Hongbao; Hao, Yaoyao; Zhang, Shaomin; Wang, Yiwen; Chen, Weidong; Zheng, Xiaoxiang

    2017-01-01

    Objective. Previous studies have demonstrated that target direction information presented by the dorsal premotor cortex (PMd) during movement planning could be incorporated into neural decoder for achieving better decoding performance. It is still unknown whether the neural decoder combined with only target direction could work in more complex tasks where obstacles impeded direct reaching paths. Methods. In this study, spike activities were collected from the PMd of two monkeys when performing a delayed obstacle-avoidance task. We examined how target direction and intended movement selection were encoded in neuron population activities of the PMd during movement planning. The decoding performances of movement trajectory were compared for three neural decoders with no prior knowledge, or only target direction, or both target direction and intended movement selection integrated into a mixture of trajectory model (MTM). Results. We found that not only target direction but also intended movement selection was presented in neural activities of the PMd during movement planning. It was further confirmed by quantitative analysis. Combined with prior knowledge, the trajectory decoder achieved the best performance among three decoders. Conclusion. Recruiting prior knowledge about target direction and intended movement selection extracted from the PMd could enhance the decoding performance of hand trajectory in indirect reaching movement.

  7. Applying the Decoding the Disciplines Process to Teaching Structural Mechanics: An Autoethnographic Case Study

    Science.gov (United States)

    Tingerthal, John Steven

    2013-01-01

    Using case study methodology and autoethnographic methods, this study examines a process of curricular development known as "Decoding the Disciplines" (Decoding) by documenting the experience of its application in a construction engineering mechanics course. Motivated by the call to integrate what is known about teaching and learning…

  8. Using Exit Charts to Develop an Early Stopping Criterion for Turbo Decoding

    NARCIS (Netherlands)

    Potman, J.; Hoeksema, F.W.; Slump, Cornelis H.

    2004-01-01

    Early stopping criteria are used to determine when additional decoder iterations result in little or no improvement in the bit- error-rate (BER) at the output of a Turbo decoder. This paper proposes a stopping criterion based on Extrinsic Information Transfer (EXIT) charts. The generation and

  9. A Study on Decoding Models for the Reconstruction of Hand Trajectories from the Human Magnetoencephalography

    Directory of Open Access Journals (Sweden)

    Hong Gi Yeom

    2014-01-01

    Full Text Available Decoding neural signals into control outputs has been a key to the development of brain-computer interfaces (BCIs. While many studies have identified neural correlates of kinematics or applied advanced machine learning algorithms to improve decoding performance, relatively less attention has been paid to optimal design of decoding models. For generating continuous movements from neural activity, design of decoding models should address how to incorporate movement dynamics into models and how to select a model given specific BCI objectives. Considering nonlinear and independent speed characteristics, we propose a hybrid Kalman filter to decode the hand direction and speed independently. We also investigate changes in performance of different decoding models (the linear and Kalman filters when they predict reaching movements only or predict both reach and rest. Our offline study on human magnetoencephalography (MEG during point-to-point arm movements shows that the performance of the linear filter or the Kalman filter is affected by including resting states for training and predicting movements. However, the hybrid Kalman filter consistently outperforms others regardless of movement states. The results demonstrate that better design of decoding models is achieved by incorporating movement dynamics into modeling or selecting a model according to decoding objectives.

  10. Application of MTR soft-decision decoding in multiple-head ...

    Indian Academy of Sciences (India)

    known as anextrinsicinformation, is present between decoders and detectors, in such systems. The known MTR codes are found on thehard-decisionbasis, producing on their output only symbols 0/1, without any other information about decision, itself. Therefore, our idea was to somehow implement soft-decision decoding ...

  11. The Contribution of Attentional Control and Working Memory to Reading Comprehension and Decoding

    Science.gov (United States)

    Arrington, C. Nikki; Kulesz, Paulina A.; Francis, David J.; Fletcher, Jack M.; Barnes, Marcia A.

    2014-01-01

    Little is known about how specific components of working memory, namely, attentional processes including response inhibition, sustained attention, and cognitive inhibition, are related to reading decoding and comprehension. The current study evaluated the relations of reading comprehension, decoding, working memory, and attentional control in…

  12. Promoter decoding of transcription factor dynamics involves a trade-off between noise and control of gene expression.

    Science.gov (United States)

    Hansen, Anders S; O'Shea, Erin K

    2013-11-05

    Numerous transcription factors (TFs) encode information about upstream signals in the dynamics of their activation, but how downstream genes decode these dynamics remains poorly understood. Using microfluidics to control the nucleocytoplasmic translocation dynamics of the budding yeast TF Msn2, we elucidate the principles that govern how different promoters convert dynamical Msn2 input into gene expression output in single cells. Combining modeling and experiments, we classify promoters according to their signal-processing behavior and reveal that multiple, distinct gene expression programs can be encoded in the dynamics of Msn2. We show that both oscillatory TF dynamics and slow promoter kinetics lead to higher noise in gene expression. Furthermore, we show that the promoter activation timescale is related to nucleosome remodeling. Our findings imply a fundamental trade-off: although the cell can exploit different promoter classes to differentially control gene expression using TF dynamics, gene expression noise fundamentally limits how much information can be encoded in the dynamics of a single TF and reliably decoded by promoters.

  13. Reading component skills in dyslexia: word recognition, comprehension and processing speed

    Directory of Open Access Journals (Sweden)

    Darlene Godoy Oliveira

    2014-11-01

    Full Text Available The cognitive model of reading comprehension posits that reading comprehension is a result of the interaction between decoding and linguistic comprehension. Recently, the notion of decoding skill was expanded to include word recognition. In addition, some studies suggest that other skills could be integrated into this model, like processing speed, and have consistently indicated that this skill influences and is an important predictor of the main components of the model, such as vocabulary for comprehension and phonological awareness of word recognition. The following study evaluated the components of the reading comprehension model and predictive skills in children and adolescents with dyslexia. 40 children and adolescents (8-13 years were divided in a Dyslexic Group (DG, 18 children, MA = 10.78, SD = 1.66 and Control Group (CG 22 children, MA = 10.59, SD = 1.86. All were students from the 2nd to 8th grade of elementary school and groups were equivalent in school grade, age, gender, and IQ. Oral and reading comprehension, word recognition, processing speed, picture naming, receptive vocabulary and phonological awareness were assessed. There were no group differences regarding the accuracy in oral and reading comprehension, phonological awareness, naming, and vocabulary scores. DG performed worse than the CG in word recognition (general score and orthographic confusion items and were slower in naming. Results corroborated the literature regarding word recognition and processing speed deficits in dyslexia. However, dyslexics can achieve normal scores on reading comprehension test. Data supports the importance of delimitation of different reading strategies embedded in the word recognition component. The role of processing speed in reading problems remain unclear.

  14. The Distribution of Talker Variability Impacts Infants’ Word Learning

    Directory of Open Access Journals (Sweden)

    Carolyn Quam

    2017-01-01

    Full Text Available Infants struggle to apply earlier-demonstrated sound-discrimination abilities to later word learning, attending to non-constrastive acoustic dimensions (e.g., Hay et al., 2015, and not always to contrastive dimensions (e.g., Stager & Werker, 1997. One hint about the nature of infants’ difficulties comes from the observation that input from multiple talkers can improve word learning (Rost & McMurray, 2009. This may be because, when a single talker says both of the to-be-learned words, consistent talker’s-voice characteristics make the acoustics of the two words more overlapping (Apfelbaum & McMurray, 2011. Here, we test that notion. We taught 14-month-old infants two similar-sounding words in the Switch habituation paradigm. The same amount of overall talker variability was present as in prior multiple-talker experiments, but male and female talkers said different words, creating a gender-word correlation. Under an acoustic-similarity account, correlated talker gender should help to separate words acoustically and facilitate learning. Instead, we found that correlated talker gender impaired learning of word-object pairings compared with uncorrelated talker gender—even when gender-word pairings were always maintained in test—casting doubt on one account of the beneficial effects of talker variability. We discuss several alternate potential explanations for this effect.

  15. Neural Correlates of Task-Irrelevant First and Second Language Emotion Words — Evidence from the Face-Word Stroop Task

    Directory of Open Access Journals (Sweden)

    Lin Fan

    2016-11-01

    Full Text Available Emotionally valenced words have thus far not been empirically examined in a bilingual population with the emotional face-word Stroop paradigm. Chinese-English bilinguals were asked to identify the facial expressions of emotion with their first (L1 or second (L2 language task-irrelevant emotion words superimposed on the face pictures. We attempted to examine how the emotional content of words modulates behavioral performance and cerebral functioning in the bilinguals’ two languages. The results indicated that there were significant congruency effects for both L1 and L2 emotion words, and that identifiable differences in the magnitude of Stroop effect between the two languages were also observed, suggesting L1 is more capable of activating the emotional response to word stimuli. For event-related potentials (ERPs data, an N350-550 effect was observed only in L1 task with greater negativity for incongruent than congruent trials. The size of N350-550 effect differed across languages, whereas no identifiable language distinction was observed in the effect of conflict slow potential (conflict SP. Finally, more pronounced negative amplitude at 230-330 ms was observed in L1 than in L2, but only for incongruent trials. This negativity, likened to an orthographic decoding N250, may reflect the extent of attention to emotion word processing at word-form level, while N350-550 reflects a complicated set of processes in the conflict processing. Overall, the face-word congruency effect has reflected identifiable language distinction at 230-330 and 350-550 ms, which provides supporting evidence for the theoretical proposals assuming attenuated emotionality of L2 processing.

  16. Neural Correlates of Task-Irrelevant First and Second Language Emotion Words - Evidence from the Emotional Face-Word Stroop Task.

    Science.gov (United States)

    Fan, Lin; Xu, Qiang; Wang, Xiaoxi; Zhang, Feng; Yang, Yaping; Liu, Xiaoping

    2016-01-01

    Emotionally valenced words have thus far not been empirically examined in a bilingual population with the emotional face-word Stroop paradigm. Chinese-English bilinguals were asked to identify the facial expressions of emotion with their first (L1) or second (L2) language task-irrelevant emotion words superimposed on the face pictures. We attempted to examine how the emotional content of words modulated behavioral performance and cerebral functioning in the bilinguals' two languages. The results indicated that there were significant congruency effects for both L1 and L2 emotion words, and that identifiable differences in the magnitude of the Stroop effect between the two languages were also observed, suggesting L1 is more capable of activating the emotional response to word stimuli. For event-related potentials data, an N350-550 effect was observed only in the L1 task with greater negativity for incongruent than congruent trials. The size of the N350-550 effect differed across languages, whereas no identifiable language distinction was observed in the effect of conflict slow potential (conflict SP). Finally, more pronounced negative amplitude at 230-330 ms was observed in L1 than in L2, but only for incongruent trials. This negativity, likened to an orthographic decoding N250, may reflect the extent of attention to emotion word processing at word-form level, while the N350-550 reflects a complicated set of processes in the conflict processing. Overall, the face-word congruency effect has reflected identifiable language distinction at 230-330 and 350-550 ms, which provides supporting evidence for the theoretical proposals assuming attenuated emotionality of L2 processing.

  17. Iterative Decoding for an Optical CDMA based Laser communication System

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Young; Kim, Eun Cheol [Kwangwoon Univ., Seoul (Korea, Republic of); Cha, Jae Sang [Seoul National Univ. of Technology, Seoul (Korea, Republic of)

    2008-11-15

    An optical CDMA(code division multiple access)based Laser communication system has attracted much attention since it requires minimal optical Laser signal processing and it is virtually delay free, while from the theoretical point of view, its performance depends on the auto and cross correlation properties of employed sequences. Various kinds of channel coding schemes for optical CDMA based Laser communication systems have been proposed and analyzed to compensate nonideal channel and receiver conditions in impaired photon channels. In this paper, we propose and analyze an iterative decoding of optical CDMA based Laser communication signals for both shot noise limited and thermal noise limited systems. It is assumed that optical channel is an intensity modulated (IM)channel and direct detection scheme is employed to detect the received optical signal. The performance is evaluated in terms of bit error probability and throughput. It is demonstrated that the BER and throughput performance is substantially improved with interleaver length for a fixed code rate and with alphabet size of PPM (pulse position modulation). Also, the BER and throughput performance is significantly enhanced with the number of iterations for decoding process. The results in this paper can be applied to the optical CDMA based Laser communication network with multiple access applications.

  18. Iterative Decoding for an Optical CDMA based Laser communication System

    International Nuclear Information System (INIS)

    Kim, Jin Young; Kim, Eun Cheol; Cha, Jae Sang

    2008-01-01

    An optical CDMA(code division multiple access)based Laser communication system has attracted much attention since it requires minimal optical Laser signal processing and it is virtually delay free, while from the theoretical point of view, its performance depends on the auto and cross correlation properties of employed sequences. Various kinds of channel coding schemes for optical CDMA based Laser communication systems have been proposed and analyzed to compensate nonideal channel and receiver conditions in impaired photon channels. In this paper, we propose and analyze an iterative decoding of optical CDMA based Laser communication signals for both shot noise limited and thermal noise limited systems. It is assumed that optical channel is an intensity modulated (IM)channel and direct detection scheme is employed to detect the received optical signal. The performance is evaluated in terms of bit error probability and throughput. It is demonstrated that the BER and throughput performance is substantially improved with interleaver length for a fixed code rate and with alphabet size of PPM (pulse position modulation). Also, the BER and throughput performance is significantly enhanced with the number of iterations for decoding process. The results in this paper can be applied to the optical CDMA based Laser communication network with multiple access applications

  19. Frame Decoder for Consultative Committee for Space Data Systems (CCSDS)

    Science.gov (United States)

    Reyes, Miguel A. De Jesus

    2014-01-01

    GNU Radio is a free and open source development toolkit that provides signal processing to implement software radios. It can be used with low-cost external RF hardware to create software defined radios, or without hardware in a simulation-like environment. GNU Radio applications are primarily written in Python and C++. The Universal Software Radio Peripheral (USRP) is a computer-hosted software radio designed by Ettus Research. The USRP connects to a host computer via high-speed Gigabit Ethernet. Using the open source Universal Hardware Driver (UHD), we can run GNU Radio applications using the USRP. An SDR is a "radio in which some or all physical layer functions are software defined"(IEEE Definition). A radio is any kind of device that wirelessly transmits or receives radio frequency (RF) signals in the radio frequency. An SDR is a radio communication system where components that have been typically implemented in hardware are implemented in software. GNU Radio has a generic packet decoder block that is not optimized for CCSDS frames. Using this generic packet decoder will add bytes to the CCSDS frames and will not permit for bit error correction using Reed-Solomon. The CCSDS frames consist of 256 bytes, including a 32-bit sync marker (0x1ACFFC1D). This frames are generated by the Space Data Processor and GNU Radio will perform the modulation and framing operations, including frame synchronization.

  20. A method for decoding the neurophysiological spike-response transform.

    Science.gov (United States)

    Stern, Estee; García-Crescioni, Keyla; Miller, Mark W; Peskin, Charles S; Brezina, Vladimir

    2009-11-15

    Many physiological responses elicited by neuronal spikes-intracellular calcium transients, synaptic potentials, muscle contractions-are built up of discrete, elementary responses to each spike. However, the spikes occur in trains of arbitrary temporal complexity, and each elementary response not only sums with previous ones, but can itself be modified by the previous history of the activity. A basic goal in system identification is to characterize the spike-response transform in terms of a small number of functions-the elementary response kernel and additional kernels or functions that describe the dependence on previous history-that will predict the response to any arbitrary spike train. Here we do this by developing further and generalizing the "synaptic decoding" approach of Sen et al. (1996). Given the spike times in a train and the observed overall response, we use least-squares minimization to construct the best estimated response and at the same time best estimates of the elementary response kernel and the other functions that characterize the spike-response transform. We avoid the need for any specific initial assumptions about these functions by using techniques of mathematical analysis and linear algebra that allow us to solve simultaneously for all of the numerical function values treated as independent parameters. The functions are such that they may be interpreted mechanistically. We examine the performance of the method as applied to synthetic data. We then use the method to decode real synaptic and muscle contraction transforms.

  1. The Effects of Learning from Word Pairs on Word Knowledge

    Directory of Open Access Journals (Sweden)

    Shamsudin Sarimah

    2015-01-01

    Full Text Available Vocabulary plays an essential role in language learning. The lack of vocabulary might cause incompetency to language users. It is therefore very important for language instructors to find suitable ways of teaching vocabulary since learning vocabulary consists of learning various aspects of word knowledge. These aspects include orthography, meaning and form, collocation, association and grammatical functions. There are various methods that could be used in gaining aspects of word knowledge. The purpose of this study is to investigate to what extent are aspects of word knowledge gained by learning from word pairs. 120 secondary school students were divided into four groups of thirty students. The first group was given a set of Malay Translation, the second, English Translation, the third, Malay Definition and the fourth, English Definition word pair to learn followed by word knowledge tests. The results show that all word pairs promote large gains in learning aspects of word knowledge. The scores between the groups were also compared and it was found that the mean score of the Malay Definition word pair group is the highest, followed by the Malay Translation word pair group, the English Translation word pair group, and English Definition word pair group.

  2. Accessing the spoken word

    OpenAIRE

    Goldman, Jerry; Renals, Steve; Bird, Steven; de Jong, Franciska; Federico, Marcello; Fleischhauer, Carl; Kornbluh, Mark; Lamel, Lori; Oard, Douglas W; Stewart, Claire; Wright, Richard

    2005-01-01

    Spoken-word audio collections cover many domains, including radio and television broadcasts, oral narratives, governmental proceedings, lectures, and telephone conversations. The collection, access, and preservation of such data is stimulated by political, economic, cultural, and educational needs. This paper outlines the major issues in the field, reviews the current state of technology, examines the rapidly changing policy issues relating to privacy and copyright, and presents issues relati...

  3. Nine Words - Nine Columns

    DEFF Research Database (Denmark)

    Trempe Jr., Robert B.; Buthke, Jan

    2016-01-01

    This book records the efforts of a one-week joint workshop between Master students from Studio 2B of Arkitektskolen Aarhus and Master students from the Harbin Institute of Technology in Harbin, China. The workshop employed nine action words to instigate team-based investigation into the effects o...... as formwork for the shaping of wood veneer. The resulting columns ‘wear’ every aspect of this design pipeline process and display the power of process towards an architectural resolution....

  4. Locating and decoding barcodes in fuzzy images captured by smart phones

    Science.gov (United States)

    Deng, Wupeng; Hu, Jiwei; Liu, Quan; Lou, Ping

    2017-07-01

    With the development of barcodes for commercial use, people's requirements for detecting barcodes by smart phone become increasingly pressing. The low quality of barcode image captured by mobile phone always affects the decoding and recognition rates. This paper focuses on locating and decoding EAN-13 barcodes in fuzzy images. We present a more accurate locating algorithm based on segment length and high fault-tolerant rate algorithm for decoding barcodes. Unlike existing approaches, location algorithm is based on the edge segment length of EAN -13 barcodes, while our decoding algorithm allows the appearance of fuzzy region in barcode image. Experimental results are performed on damaged, contaminated and scratched digital images, and provide a quite promising result for EAN -13 barcode location and decoding.

  5. Efficient Dual Domain Decoding of Linear Block Codes Using Genetic Algorithms

    Directory of Open Access Journals (Sweden)

    Ahmed Azouaoui

    2012-01-01

    Full Text Available A computationally efficient algorithm for decoding block codes is developed using a genetic algorithm (GA. The proposed algorithm uses the dual code in contrast to the existing genetic decoders in the literature that use the code itself. Hence, this new approach reduces the complexity of decoding the codes of high rates. We simulated our algorithm in various transmission channels. The performance of this algorithm is investigated and compared with competitor decoding algorithms including Maini and Shakeel ones. The results show that the proposed algorithm gives large gains over the Chase-2 decoding algorithm and reach the performance of the OSD-3 for some quadratic residue (QR codes. Further, we define a new crossover operator that exploits the domain specific information and compare it with uniform and two point crossover. The complexity of this algorithm is also discussed and compared to other algorithms.

  6. Analysis of Iterated Hard Decision Decoding of Product Codes with Reed-Solomon Component Codes

    DEFF Research Database (Denmark)

    Justesen, Jørn; Høholdt, Tom

    2007-01-01

    Products of Reed-Solomon codes are important in applications because they offer a combination of large blocks, low decoding complexity, and good performance. A recent result on random graphs can be used to show that with high probability a large number of errors can be corrected by iterating mini...... minimum distance decoding. We present an analysis related to density evolution which gives the exact asymptotic value of the decoding threshold and also provides a closed form approximation to the distribution of errors in each step of the decoding of finite length codes.......Products of Reed-Solomon codes are important in applications because they offer a combination of large blocks, low decoding complexity, and good performance. A recent result on random graphs can be used to show that with high probability a large number of errors can be corrected by iterating...

  7. WordPress multisite administration

    CERN Document Server

    Longren, Tyler

    2013-01-01

    This is a simple, concise guide with a step-by-step approach, packed with screenshots and examples to set up and manage a network blog using WordPress.WordPress Multisite Administration is ideal for anyone wanting to familiarize themselves with WordPress Multisite. You'll need to know the basics about WordPress, and having at least a broad understanding of HTML, CSS, and PHP will help, but isn't required.

  8. Optokinetic Stimulation Affects Word Omissions but Not Stimulus-Centered Reading Errors in Paragraph Reading in Neglect Dyslexia

    Science.gov (United States)

    Reinhart, Stefan; Schindler, Igor; Kerkhoff, Georg

    2011-01-01

    Patients with right hemisphere lesions often omit or misread words on the left side of a text or the initial letters of single words, a phenomenon termed neglect dyslexia (ND). Omissions of words on the contralesional side of the page are considered as egocentric or space-based errors, whereas misread words can be viewed as a type of…

  9. Real-time fMRI pattern decoding and neurofeedback using FRIEND: an FSL-integrated BCI toolbox.

    Science.gov (United States)

    Sato, João R; Basilio, Rodrigo; Paiva, Fernando F; Garrido, Griselda J; Bramati, Ivanei E; Bado, Patricia; Tovar-Moll, Fernanda; Zahn, Roland; Moll, Jorge

    2013-01-01

    The demonstration that humans can learn to modulate their own brain activity based on feedback of neurophysiological signals opened up exciting opportunities for fundamental and applied neuroscience. Although EEG-based neurofeedback has been long employed both in experimental and clinical investigation, functional MRI (fMRI)-based neurofeedback emerged as a promising method, given its superior spatial resolution and ability to gauge deep cortical and subcortical brain regions. In combination with improved computational approaches, such as pattern recognition analysis (e.g., Support Vector Machines, SVM), fMRI neurofeedback and brain decoding represent key innovations in the field of neuromodulation and functional plasticity. Expansion in this field and its applications critically depend on the existence of freely available, integrated and user-friendly tools for the neuroimaging research community. Here, we introduce FRIEND, a graphic-oriented user-friendly interface package for fMRI neurofeedback and real-time multivoxel pattern decoding. The package integrates routines for image preprocessing in real-time, ROI-based feedback (single-ROI BOLD level and functional connectivity) and brain decoding-based feedback using SVM. FRIEND delivers an intuitive graphic interface with flexible processing pipelines involving optimized procedures embedding widely validated packages, such as FSL and libSVM. In addition, a user-defined visual neurofeedback module allows users to easily design and run fMRI neurofeedback experiments using ROI-based or multivariate classification approaches. FRIEND is open-source and free for non-commercial use. Processing tutorials and extensive documentation are available.

  10. Real-time fMRI pattern decoding and neurofeedback using FRIEND: an FSL-integrated BCI toolbox.

    Directory of Open Access Journals (Sweden)

    João R Sato

    Full Text Available The demonstration that humans can learn to modulate their own brain activity based on feedback of neurophysiological signals opened up exciting opportunities for fundamental and applied neuroscience. Although EEG-based neurofeedback has been long employed both in experimental and clinical investigation, functional MRI (fMRI-based neurofeedback emerged as a promising method, given its superior spatial resolution and ability to gauge deep cortical and subcortical brain regions. In combination with improved computational approaches, such as pattern recognition analysis (e.g., Support Vector Machines, SVM, fMRI neurofeedback and brain decoding represent key innovations in the field of neuromodulation and functional plasticity. Expansion in this field and its applications critically depend on the existence of freely available, integrated and user-friendly tools for the neuroimaging research community. Here, we introduce FRIEND, a graphic-oriented user-friendly interface package for fMRI neurofeedback and real-time multivoxel pattern decoding. The package integrates routines for image preprocessing in real-time, ROI-based feedback (single-ROI BOLD level and functional connectivity and brain decoding-based feedback using SVM. FRIEND delivers an intuitive graphic interface with flexible processing pipelines involving optimized procedures embedding widely validated packages, such as FSL and libSVM. In addition, a user-defined visual neurofeedback module allows users to easily design and run fMRI neurofeedback experiments using ROI-based or multivariate classification approaches. FRIEND is open-source and free for non-commercial use. Processing tutorials and extensive documentation are available.

  11. Usage of the word 'ether'

    International Nuclear Information System (INIS)

    Duffy, M.C.

    1980-01-01

    Confusion has been caused by scientists using the one word 'ether' to classify models differing from each other in important respects. Major roles assigned to the word are examined, and the nature of modern ether theories surveyed. The part played by the several meanings attached to the word, in the ether concept, is outlined. (author)

  12. Build an Interactive Word Wall

    Science.gov (United States)

    Jackson, Julie

    2018-01-01

    Word walls visually display important vocabulary covered during class. Although teachers have often been encouraged to post word walls in their classrooms, little information is available to guide them. This article describes steps science teachers can follow to transform traditional word walls into interactive teaching tools. It also describes a…

  13. Gesture en route to words

    DEFF Research Database (Denmark)

    Jensen de López, Kristine M.

    2010-01-01

    the children showed an early preference for the gestural or vocal modality. Through Analyzes of two-element combinations of words and/or gestures, we observd a relative increase in cross-modal (gesture-word and two-word) combinations. The results are discussed in terms understanding gestures as a transition...

  14. Brain activation during word identification and word recognition

    DEFF Research Database (Denmark)

    Jernigan, Terry L.; Ostergaard, Arne L.; Law, Ian

    1998-01-01

    between memory scores obtained with the two kinds of tasks. However, there is continuing controversy about the meaning of these dissociations. In recent studies, Ostergaard (1998a, Memory Cognit. 26:40-60; 1998b, J. Int. Neuropsychol. Soc., in press) showed that simply degrading visual word stimuli can...... dramatically alter the degree to which word priming shows a dissociation from word recognition; i.e., effects of a number of factors on priming paralleled their effects on recognition memory tests when the words were degraded at test. In the present study, cerebral blood flow changes were measured while...... subjects performed the word identification (reading) and recognition memory tasks used previously by Ostergaard. The results are the direct comparisons of the two tasks and the effects of stimulus degradation on blood flow patterns during the tasks. Clear differences between word identification and word...

  15. More than words: fast acquisition and generalization of orthographic regularities during novel word learning in adults.

    Science.gov (United States)

    Laine, Matti; Polonyi, Tünde; Abari, Kálmán

    2014-08-01

    In literates, reading is a fundamental channel for acquiring new vocabulary both in the mother tongue and in foreign languages. By using an artificial language learning task, we examined the acquisition of novel written words and their embedded regularities (an orthographic surface feature and a syllabic feature) in three groups of university students with different exposures (Group 1 saw 2 words once, Group 2 saw 20 words once, Group 3 saw 20 words three times). Recognition memory results for Groups 2 and 3 indicated that adults can learn novel written words even with just a single exposure, albeit repeated exposure improved target detection. A generalization task revealed that even the minimal exposure in Group 1 was enough for acquisition of the two embedded regularities. More exemplars and repeated exposure provided more robust effects for the syllable regularity. Finally, post-test interview showed that repeated exposure was needed to become aware of the regularities. The present results show that adults learn novel written words and their inherent regularities in a fast and effective fashion.

  16. Developmental origins of recoding and decoding in memory.

    Science.gov (United States)

    Kibbe, Melissa M; Feigenson, Lisa

    2014-12-01

    Working memory is severely limited in both adults and children, but one way that adults can overcome this limit is through the process of recoding. Recoding happens when representations of individual items are chunked together into a higher order representation, and the chunk is assigned a label. That label can then be decoded to retrieve the individual items from long-term memory. Whereas this ability has been extensively studied in adults (as, for example, in classic studies of memory in chess), little is known about recoding's developmental origins. Here we asked whether 2- to 3-year-old children also can recode-that is, can they restructure representations of individual objects into a higher order chunk, assign this new representation a verbal label, and then later decode the label to retrieve the represented individuals from memory. In Experiments 1 and 2, we showed children identical blocks that could be connected to make tools. Children learned a novel name for a tool that could be built from two blocks, and for a tool that could be built from three blocks. Later we told children that one of the tools was hidden in a box, with no visual information provided. Children were allowed to search the box and retrieve varying numbers of blocks. Critically, the retrieved blocks were identical and unconnected, so the only way children could know whether any blocks remained was by using the verbal label to recall how many objects comprised each tool (or chunk). We found that even children who could not yet count adjusted their searching of the box depending on the label they had heard. This suggests that they had recoded representations of individual blocks into higher-order chunks, attached labels to the chunks, and then later decoded the labels to infer how many blocks were hidden. In Experiments 3 and 4 we asked whether recoding also can expand the number of individual objects children could remember, as in the classic studies with adults. We found that when no

  17. Allographic Agraphia for Single letters

    OpenAIRE

    Menichelli, Alina; Machetta, Francesca; Zadini, Antonella; Semenza, Carlo

    2012-01-01

    The case is reported of a patient (PS) who, following acute encephalitis with residual occipito-temporal damage, showed a selective deficit in writing cursive letters in isolation, but no difficulty to write cursive-case words and non-words. Notably, he was able to recognize the same allographs he could not write and to produce both single letters and words in print. In addition to this selective single letter writing difficulty, the patient demonstrated an inability to correctly perform a se...

  18. Narrative-based intervention for word-finding difficulties: a case study.

    Science.gov (United States)

    Marks, Ian; Stokes, Stephanie F

    2010-01-01

    Children with word-finding difficulties manifest a high frequency of word-finding characteristics in narrative, yet word-finding interventions have concentrated on single-word treatments and outcome measures. This study measured the effectiveness of a narrative-based intervention in improving single-word picture-naming and word-finding characteristics in narrative in a case study. A case study, quasi-experimental design was employed. The participant was tested on picture naming and spoken word to picture matching on control and treatment words at pre-, mid-, and post-therapy and an 8-month maintenance point. Narrative samples at pre- and post-therapy were analysed for word-finding characteristics and language production. A narrative-based language intervention for word-finding difficulties (NBLI-WF) was carried out for eight sessions, over 3 weeks. The data were subjected to a repeated-measures trend analysis for dichotomous data. Significant improvement occurred for naming accuracy of treatment, but not for control words. The pattern of word-finding characteristics in narrative changed, but the frequency did not reduce. NBLI-WF was effective in improving naming accuracy in this single case, but there were limitations to the research. Further research is required to assess the changes that may occur in language production and word-finding characteristics in narrative. Community clinicians are encouraged to refine clinical practice to ensure clinical research meets quality indicators.

  19. Beating the classical limits of information transmission using a quantum decoder

    Science.gov (United States)

    Chapman, Robert J.; Karim, Akib; Huang, Zixin; Flammia, Steven T.; Tomamichel, Marco; Peruzzo, Alberto

    2018-01-01

    Encoding schemes and error-correcting codes are widely used in information technology to improve the reliability of data transmission over real-world communication channels. Quantum information protocols can further enhance the performance in data transmission by encoding a message in quantum states; however, most proposals to date have focused on the regime of a large number of uses of the noisy channel, which is unfeasible with current quantum technology. We experimentally demonstrate quantum enhanced communication over an amplitude damping noisy channel with only two uses of the channel per bit and a single entangling gate at the decoder. By simulating the channel using a photonic interferometric setup, we experimentally increase the reliability of transmitting a data bit by greater than 20 % for a certain damping range over classically sending the message twice. We show how our methodology can be extended to larger systems by simulating the transmission of a single bit with up to eight uses of the channel and a two-bit message with three uses of the channel, predicting a quantum enhancement in all cases.

  20. Upper limb movements can be decoded from the time-domain of low-frequency EEG.

    Science.gov (United States)

    Ofner, Patrick; Schwarz, Andreas; Pereira, Joana; Müller-Putz, Gernot R

    2017-01-01

    How neural correlates of movements are represented in the human brain is of ongoing interest and has been researched with invasive and non-invasive methods. In this study, we analyzed the encoding of single upper limb movements in the time-domain of low-frequency electroencephalography (EEG) signals. Fifteen healthy subjects executed and imagined six different sustained upper limb movements. We classified these six movements and a rest class and obtained significant average classification accuracies of 55% (movement vs movement) and 87% (movement vs rest) for executed movements, and 27% and 73%, respectively, for imagined movements. Furthermore, we analyzed the classifier patterns in the source space and located the brain areas conveying discriminative movement information. The classifier patterns indicate that mainly premotor areas, primary motor cortex, somatosensory cortex and posterior parietal cortex convey discriminative movement information. The decoding of single upper limb movements is specially interesting in the context of a more natural non-invasive control of e.g., a motor neuroprosthesis or a robotic arm in highly motor disabled persons.

  1. A Prerequisite to L1 Homophone Effects in L2 Spoken-Word Recognition

    Science.gov (United States)

    Nakai, Satsuki; Lindsay, Shane; Ota, Mitsuhiko

    2015-01-01

    When both members of a phonemic contrast in L2 (second language) are perceptually mapped to a single phoneme in one's L1 (first language), L2 words containing a member of that contrast can spuriously activate L2 words in spoken-word recognition. For example, upon hearing cattle, Dutch speakers of English are reported to experience activation…

  2. The Influence of Anticipation of Word Misrecognition on the Likelihood of Stuttering

    Science.gov (United States)

    Brocklehurst, Paul H.; Lickley, Robin J.; Corley, Martin

    2012-01-01

    This study investigates whether the experience of stuttering can result from the speaker's anticipation of his words being misrecognized. Twelve adults who stutter (AWS) repeated single words into what appeared to be an automatic speech-recognition system. Following each iteration of each word, participants provided a self-rating of whether they…

  3. Beginners Remember Orthography when They Learn to Read Words: The Case of Doubled Letters

    Science.gov (United States)

    Wright, Donna-Marie; Ehri, Linnea C.

    2007-01-01

    Sight word learning and memory were studied to clarify how early during development readers process visual letter patterns that are not dictated by phonology, and whether their word learning is influenced by the legality of letter patterns. Forty kindergartners and first graders were taught to read 12 words containing either single consonants…

  4. Between-Word Simplification Patterns in the Continuous Speech of Children with Speech Sound Disorders

    Science.gov (United States)

    Klein, Harriet B.; Liu-Shea, May

    2009-01-01

    Purpose: This study was designed to identify and describe between-word simplification patterns in the continuous speech of children with speech sound disorders. It was hypothesized that word combinations would reveal phonological changes that were unobserved with single words, possibly accounting for discrepancies between the intelligibility of…

  5. Electronic Word of Behavior

    DEFF Research Database (Denmark)

    Kunst, Katrine

    that recent years have seen a social media-facilitated move from opinion-centric eWOM (e.g. reviews) to behavior-centric (e.g. information about friends’ music consumption on Spotify). A review of the concepts of WOM and eWOM and a netnographic study reveal that the current definitions and understandings...... of the concepts do not capture this new kind of consumer-to-consumer information transfer about products and services. Consequently, we suggest an extension of those concepts: Electronic Word of Behavior....

  6. Word learning: An ERP investigation of word experience effects on recognition and word processing

    NARCIS (Netherlands)

    Balass, M.; Perfetti, C.A.; Nelson, J.R.

    2010-01-01

    Adults of varying reading comprehension skill learned a set of previously unknown rare English words (e.g., gloaming) in three different learning conditions in which the type of word knowledge was manipulated. The words were presented in one of three conditions: (1) orthography-to-meaning (no

  7. Emotion Words: Adding Face Value.

    Science.gov (United States)

    Fugate, Jennifer M B; Gendron, Maria; Nakashima, Satoshi F; Barrett, Lisa Feldman

    2017-06-12

    Despite a growing number of studies suggesting that emotion words affect perceptual judgments of emotional stimuli, little is known about how emotion words affect perceptual memory for emotional faces. In Experiments 1 and 2 we tested how emotion words (compared with control words) affected participants' abilities to select a target emotional face from among distractor faces. Participants were generally more likely to false alarm to distractor emotional faces when primed with an emotion word congruent with the face (compared with a control word). Moreover, participants showed both decreased sensitivity (d') to discriminate between target and distractor faces, as well as altered response biases (c; more likely to answer "yes") when primed with an emotion word (compared with a control word). In Experiment 3 we showed that emotion words had more of an effect on perceptual memory judgments when the structural information in the target face was limited, as well as when participants were only able to categorize the face with a partially congruent emotion word. The overall results are consistent with the idea that emotion words affect the encoding of emotional faces in perceptual memory. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. English words structure, history, usage

    CERN Document Server

    Katamba, Francis

    2015-01-01

    How do we find the right word for the job? Where does that word come from? Why do we spell it like that? And how do we know what it means? Words are all around us - we use them every day to communicate our joys, fears, hopes, opinions, wishes and demands - but we don't often think about them too deeply. In this highly accessible introduction to English words, the reader will discover what the study of words can tell them about the extraordinary richness and complexity of our daily vocabulary and about the nature of language in general. Assuming no prior knowledge of linguistics, the book covers a wide range of topics, including the structure of words, the meaning of words, how their spelling relates to pronunciation, how new words are manufactured or imported from other languages, and how the meaning of words changes with the passage of time. It also investigates how the mind deals with words by highlighting the amazing intellectual feat performed routinely when the right word is retrieved from the mental dic...

  9. WordPress for dummies

    CERN Document Server

    Sabin-Wilson, Lisa

    2014-01-01

    The bestselling WordPress guide, fully updated to cover the 2013 enhancements WordPress has millions of users, and this popular guide has sold more than 105,000 copies in its previous editions. With the newest releases of WordPress, author and WordPress expert Lisa Sabin-Wilson has completely updated the book to help you use and understand all the latest features. You'll learn about both the hosted WordPress.com version and the more flexible WordPress.org, which requires third-party hosting. Whether you're switching to WordPress from another blogging platform or just beginning to blog, you'll

  10. 78 FR 38843 - Single Application Option

    Science.gov (United States)

    2013-06-28

    ... searchable, accessible text (not an image); Microsoft Word; WordPerfect; Rich Text Format (RTF); or ASCII... notice responding to the question of a single application, all of them positive. On March 28, 2012, the...

  11. An associative account of the development of word learning.

    Science.gov (United States)

    Sloutsky, Vladimir M; Yim, Hyungwook; Yao, Xin; Dennis, Simon

    2017-09-01

    Word learning is a notoriously difficult induction problem because meaning is underdetermined by positive examples. How do children solve this problem? Some have argued that word learning is achieved by means of inference: young word learners rely on a number of assumptions that reduce the overall hypothesis space by favoring some meanings over others. However, these approaches have difficulty explaining how words are learned from conversations or text, without pointing or explicit instruction. In this research, we propose an associative mechanism that can account for such learning. In a series of experiments, 4-year-olds and adults were presented with sets of words that included a single nonsense word (e.g. dax). Some lists were taxonomic (i.,e., all items were members of a given category), some were associative (i.e., all items were associates of a given category, but not members), and some were mixed. Participants were asked to indicate whether the nonsense word was an animal or an artifact. Adults exhibited evidence of learning when lists consisted of either associatively or taxonomically related items. In contrast, children exhibited evidence of word learning only when lists consisted of associatively related items. These results present challenges to several extant models of word learning, and a new model based on the distinction between syntagmatic and paradigmatic associations is proposed. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Early attentional bias for negative words when competition is induced.

    Science.gov (United States)

    Ho, Ming-Chou; Li, Shuo-Heng; Yeh, Su-Ling

    2016-05-01

    Previous research (Zeelenberg, Wagenmakers, & Rotteveel, 2006) revealed that emotionally meaningful words were identified significantly better than neutral words, with no difference between positive and negative words. Since in that study only a single target word was displayed at a time, we hypothesized that the equivalent performances for positive and negative words were due to a lack of competition. To test this, in our Experiment 1, we replicated Zeelenberg and colleagues' finding, using emotion-laden Chinese words and the identical data-limited method, which measured the accuracy of a briefly shown target. We then introduced competition in Experiment 2 by simultaneously presenting two words during the target frame, and found evidence for an early attentional bias to negative words. In Experiment 3, we confirmed that the bias in Experiment 2 was not due to the inevitable repetition of stimuli. Taken together, these results support our hypothesis that, in the presence of competition, negative words receive attentional priority and consequently have enhanced perceptual representations.

  13. Decoding of thermal data in Fleischmann and Pons paper

    International Nuclear Information System (INIS)

    Ohashi, Hiroshi; Morozumi, Takashi

    1989-01-01

    The recent 'discovery' of cold nuclear fusion by Fleischmann and Pons (abbreviated to F and P below) contradicts the general concept of nuclear fusion between deuterium nuclei. Since they were not able to confirm a relation between the heat evolution and the production of neutrons, tritium and helium, they claimed that a new type of nuclear fusion process took place, and that the only evidence was a large amount of heat evolution. Their claim that the heat evolution exceeded breakeven, is suspicious, as there are many flaws and contradictions in their data and logic. The following shows the results of our decoding of the complicated thermal data in the F and P paper, and concludes that the heat evolution reported by the F and P paper can be adequately explained by considering a recombination of hydrogen and oxygen evolved during the experiment. (author)

  14. Remote Control and Testing of the Interactive TV-Decoder

    Directory of Open Access Journals (Sweden)

    K. Vlcek

    1995-12-01

    Full Text Available The article deals with assembling and application of a complex sequential circuit VHDL (VHSIC (Very High-Speed Integrated Circuit Hardware Description Language model. The circuit model is a core of a cryptographic device for the signal encoding and decoding of discreet transmissions by TV-cable net. The cryptographic algorithm is changable according to the user's wishes. The principles of creation and example implementations are presented in the article. The behavioural model is used to minimize mistakes in the ASICs (Application Specific Integrated Circuits. The circuit implementation uses the FPGA (Field Programmable Gate Array technology. The diagnostics of the circuit is based on remote testing by the IEEE Std 1149.1-1990. The VHDL model of diagnostic subsystem is created as an orthogonal model in relation to the cryptographic circuit VHDL model.

  15. Low Bit Rate Motion Video Coder/Decoder For Teleconferencing

    Science.gov (United States)

    Koga, T.; Niwa, K.; Iijima, Y.; Iinuma, K.

    1987-07-01

    This paper describes motion video compression transmission for teleconferencing at a subprimary rate, i.e., at 384 kbits/s, including audio signal through the integrated services digital network (ISDN) HO channel. A subprimary rate video coder/decoder (codec), NETEC-XV, is available commercially that can operate at any bit rate (in multiples of 64 kbits/s) from 384 to 2048 kbits/s. In this paper, new algorithms are described that have been very useful in lowering the bit rate to 384 kbits/s. These algorithms are (1) separation of moving and still parts, followed by encoding of the two parts using different sets of parameters, and (2) scene change detection and its application to encoding parameter control. According to a brief subjective evaluation, the codec provides good picture quality even at a transmission bit rate of 384 kbits/s.

  16. Exact performance analysis of decode-and-forward opportunistic relaying

    KAUST Repository

    Tourki, Kamel

    2010-06-01

    In this paper, we investigate a dual-hop decode-and-forward opportunistic relaying scheme where the source may or may not be able to communicate directly with the destination. In our study, we consider a regenerative relaying scheme in which the decision to cooperate takes into account the effect of the possible erroneously detected and transmitted data at the best relay. We derive an exact closed-form expression for the end-to-end bit-error rate (BER) of binary phase-shift keying (BPSK) modulation based on the exact statistics of each hop. Unlike existing works where the analysis focused on high signal-to-noise ratio (SNR) regime, such results are important to enable the designers to take decisions regarding practical systems that operate at low SNR regime. We show that performance simulation results coincide with our analytical results.

  17. Outage analysis of opportunistic decode-and-forward relaying

    KAUST Repository

    Tourki, Kamel

    2010-09-01

    In this paper, we investigate a dual-hop opportunistic decode-and-forward relaying scheme where the source may or not be able to communicate directly with the destination. We first derive statistics based on exact probability density function (PDF) of each hop. Then, the PDFs are used to determine closed-form outage probability expression for a transmission rate R. Furthermore, we evaluate the asymptotic outage performance and the diversity order is deduced. Unlike existing works where the analysis focused on high signal-to-noise ratio (SNR) regime, such results are important to enable the designers to take decisions regarding practical systems that operate at low SNR regime. We show that performance simulation results coincide with our analytical results under practical assumption of unbalanced hops. © 2010 IEEE.

  18. Decoding Computer Games: Studying “Special Operation 85”

    Directory of Open Access Journals (Sweden)

    Bahareh Jalalzadeh

    2009-11-01

    Full Text Available As other media, computer games convey messages which have tow features: explicit and implicit. Semiologically studying computer games and comparing them with narrative structures, the present study attempts to discover the messages they convey. Therefore we have studied and decoded “Special operation 85” as a semiological text. Results show that the game’s features, as naming, interests and motivations of the engaged people, and the events narrated, all lead the producers to their goals of introducing and publicizing Iranian-Islamic cultural values. Although this feature makes “Special Opreation 85” a unique game, it fails in its attempt to produce a mythical personage in Iranian-Islamic cultural context.

  19. Decoding of thermal data in Fleischmann and Pons paper

    Energy Technology Data Exchange (ETDEWEB)

    Ohashi, Hiroshi; Morozumi, Takashi (Hokkaido Univ., Sapporo (Japan). Faculty of Engineering)

    1989-07-01

    The recent 'discovery' of cold nuclear fusion by Fleischmann and Pons (abbreviated to F and P below) contradicts the general concept of nuclear fusion between deuterium nuclei. Since they were not able to confirm a relation between the heat evolution and the production of neutrons, tritium and helium, they claimed that a new type of nuclear fusion process took place, and that the only evidence was a large amount of heat evolution. Their claim that the heat evolution exceeded breakeven, is suspicious, as there are many flaws and contradictions in their data and logic. The following shows the results of our decoding of the complicated thermal data in the F and P paper, and concludes that the heat evolution reported by the F and P paper can be adequately explained by considering a recombination of hydrogen and oxygen evolved during the experiment. (author).

  20. Communicating with sentences: A multi-word naming game model

    Science.gov (United States)

    Lou, Yang; Chen, Guanrong; Hu, Jianwei

    2018-01-01

    Naming game simulates the process of naming an object by a single word, in which a population of communicating agents can reach global consensus asymptotically through iteratively pair-wise conversations. We propose an extension of the single-word model to a multi-word naming game (MWNG), simulating the case of describing a complex object by a sentence (multiple words). Words are defined in categories, and then organized as sentences by combining them from different categories. We refer to a formatted combination of several words as a pattern. In such an MWNG, through a pair-wise conversation, it requires the hearer to achieve consensus with the speaker with respect to both every single word in the sentence as well as the sentence pattern, so as to guarantee the correct meaning of the saying; otherwise, they fail reaching consensus in the interaction. We validate the model in three typical topologies as the underlying communication network, and employ both conventional and man-designed patterns in performing the MWNG.

  1. Efficiently sphere-decodable physical layer transmission schemes for wireless storage networks

    Science.gov (United States)

    Lu, Hsiao-Feng Francis; Barreal, Amaro; Karpuk, David; Hollanti, Camilla

    2016-12-01

    Three transmission schemes over a new type of multiple-access channel (MAC) model with inter-source communication links are proposed and investigated in this paper. This new channel model is well motivated by, e.g., wireless distributed storage networks, where communication to repair a lost node takes place from helper nodes to a repairing node over a wireless channel. Since in many wireless networks nodes can come and go in an arbitrary manner, there must be an inherent capability of inter-node communication between every pair of nodes. Assuming that communication is possible between every pair of helper nodes, the newly proposed schemes are based on various smart time-sharing and relaying strategies. In other words, certain helper nodes will be regarded as relays, thereby converting the conventional uncooperative multiple-access channel to a multiple-access relay channel (MARC). The diversity-multiplexing gain tradeoff (DMT) of the system together with efficient sphere-decodability and low structural complexity in terms of the number of antennas required at each end is used as the main design objectives. While the optimal DMT for the new channel model is fully open, it is shown that the proposed schemes outperform the DMT of the simple time-sharing protocol and, in some cases, even the optimal uncooperative MAC DMT. While using a wireless distributed storage network as a motivating example throughout the paper, the MAC transmission techniques proposed here are completely general and as such applicable to any MAC communication with inter-source communication links.

  2. Cellular automaton decoders of topological quantum memories in the fault tolerant setting

    International Nuclear Information System (INIS)

    Herold, Michael; Eisert, Jens; Kastoryano, Michael J; Campbell, Earl T

    2017-01-01

    Active error decoding and correction of topological quantum codes—in particular the toric code—remains one of the most viable routes to large scale quantum information processing. In contrast, passive error correction relies on the natural physical dynamics of a system to protect encoded quantum information. However, the search is ongoing for a completely satisfactory passive scheme applicable to locally interacting two-dimensional systems. Here, we investigate dynamical decoders that provide passive error correction by embedding the decoding process into local dynamics. We propose a specific discrete time cellular-automaton decoder in the fault tolerant setting and provide numerical evidence showing that the logical qubit has a survival time extended by several orders of magnitude over that of a bare unencoded qubit. We stress that (asynchronous) dynamical decoding gives rise to a Markovian dissipative process. We hence equate cellular-automaton decoding to a fully dissipative topological quantum memory, which removes errors continuously. In this sense, uncontrolled and unwanted local noise can be corrected for by a controlled local dissipative process. We analyze the required resources, commenting on additional polylogarithmic factors beyond those incurred by an ideal constant resource dynamical decoder. (paper)

  3. Multiscale decoding for reliable brain-machine interface performance over time.

    Science.gov (United States)

    Han-Lin Hsieh; Wong, Yan T; Pesaran, Bijan; Shanechi, Maryam M

    2017-07-01

    Recordings from invasive implants can degrade over time, resulting in a loss of spiking activity for some electrodes. For brain-machine interfaces (BMI), such a signal degradation lowers control performance. Achieving reliable performance over time is critical for BMI clinical viability. One approach to improve BMI longevity is to simultaneously use spikes and other recording modalities such as local field potentials (LFP), which are more robust to signal degradation over time. We have developed a multiscale decoder that can simultaneously model the different statistical profiles of multi-scale spike/LFP activity (discrete spikes vs. continuous LFP). This decoder can also run at multiple time-scales (millisecond for spikes vs. tens of milliseconds for LFP). Here, we validate the multiscale decoder for estimating the movement of 7 major upper-arm joint angles in a non-human primate (NHP) during a 3D reach-to-grasp task. The multiscale decoder uses motor cortical spike/LFP recordings as its input. We show that the multiscale decoder can improve decoding accuracy by adding information from LFP to spikes, while running at the fast millisecond time-scale of the spiking activity. Moreover, this improvement is achieved using relatively few LFP channels, demonstrating the robustness of the approach. These results suggest that using multiscale decoders has the potential to improve the reliability and longevity of BMIs.

  4. ESVD: An Integrated Energy Scalable Framework for Low-Power Video Decoding Systems

    Directory of Open Access Journals (Sweden)

    Wen Ji

    2010-01-01

    Full Text Available Video applications using mobile wireless devices are a challenging task due to the limited capacity of batteries. The higher complex functionality of video decoding needs high resource requirements. Thus, power efficient control has become more critical design with devices integrating complex video processing techniques. Previous works on power efficient control in video decoding systems often aim at the low complexity design and not explicitly consider the scalable impact of subfunctions in decoding process, and seldom consider the relationship with the features of compressed video date. This paper is dedicated to developing an energy-scalable video decoding (ESVD strategy for energy-limited mobile terminals. First, ESVE can dynamically adapt the variable energy resources due to the device aware technique. Second, ESVD combines the decoder control with decoded data, through classifying the data into different partition profiles according to its characteristics. Third, it introduces utility theoretical analysis during the resource allocation process, so as to maximize the resource utilization. Finally, it adapts the energy resource as different energy budget and generates the scalable video decoding output under energy-limited systems. Experimental results demonstrate the efficiency of the proposed approach.

  5. Cellular automaton decoders of topological quantum memories in the fault tolerant setting

    Science.gov (United States)

    Herold, Michael; Kastoryano, Michael J.; Campbell, Earl T.; Eisert, Jens

    2017-06-01

    Active error decoding and correction of topological quantum codes—in particular the toric code—remains one of the most viable routes to large scale quantum information processing. In contrast, passive error correction relies on the natural physical dynamics of a system to protect encoded quantum information. However, the search is ongoing for a completely satisfactory passive scheme applicable to locally interacting two-dimensional systems. Here, we investigate dynamical decoders that provide passive error correction by embedding the decoding process into local dynamics. We propose a specific discrete time cellular-automaton decoder in the fault tolerant setting and provide numerical evidence showing that the logical qubit has a survival time extended by several orders of magnitude over that of a bare unencoded qubit. We stress that (asynchronous) dynamical decoding gives rise to a Markovian dissipative process. We hence equate cellular-automaton decoding to a fully dissipative topological quantum memory, which removes errors continuously. In this sense, uncontrolled and unwanted local noise can be corrected for by a controlled local dissipative process. We analyze the required resources, commenting on additional polylogarithmic factors beyond those incurred by an ideal constant resource dynamical decoder.

  6. Low Complexity List Decoding for Polar Codes with Multiple CRC Codes

    Directory of Open Access Journals (Sweden)

    Jong-Hwan Kim

    2017-04-01

    Full Text Available Polar codes are the first family of error correcting codes that provably achieve the capacity of symmetric binary-input discrete memoryless channels with low complexity. Since the development of polar codes, there have been many studies to improve their finite-length performance. As a result, polar codes are now adopted as a channel code for the control channel of 5G new radio of the 3rd generation partnership project. However, the decoder implementation is one of the big practical problems and low complexity decoding has been studied. This paper addresses a low complexity successive cancellation list decoding for polar codes utilizing multiple cyclic redundancy check (CRC codes. While some research uses multiple CRC codes to reduce memory and time complexity, we consider the operational complexity of decoding, and reduce it by optimizing CRC positions in combination with a modified decoding operation. Resultingly, the proposed scheme obtains not only complexity reduction from early stopping of decoding, but also additional reduction from the reduced number of decoding paths.

  7. Improved HDRG decoders for qudit and non-Abelian quantum error correction

    Science.gov (United States)

    Hutter, Adrian; Loss, Daniel; Wootton, James R.

    2015-03-01

    Hard-decision renormalization group (HDRG) decoders are an important class of decoding algorithms for topological quantum error correction. Due to their versatility, they have been used to decode systems with fractal logical operators, color codes, qudit topological codes, and non-Abelian systems. In this work, we develop a method of performing HDRG decoding which combines strengths of existing decoders and further improves upon them. In particular, we increase the minimal number of errors necessary for a logical error in a system of linear size L from \\Theta ({{L}2/3}) to Ω ({{L}1-ε }) for any ε \\gt 0. We apply our algorithm to decoding D({{{Z}}d}) quantum double models and a non-Abelian anyon model with Fibonacci-like fusion rules, and show that it indeed significantly outperforms previous HDRG decoders. Furthermore, we provide the first study of continuous error correction with imperfect syndrome measurements for the D({{{Z}}d}) quantum double models. The parallelized runtime of our algorithm is poly(log L) for the perfect measurement case. In the continuous case with imperfect syndrome measurements, the averaged runtime is O(1) for Abelian systems, while continuous error correction for non-Abelian anyons stays an open problem.

  8. Decoding repetitive finger movements with brain activity acquired via non-invasive electroencephalography

    Directory of Open Access Journals (Sweden)

    Andrew Young Paek

    2014-03-01

    Full Text Available We investigated how well repetitive finger tapping movements can be decoded from scalp electroencephalography (EEG signals. A linear decoder with memory was used to infer continuous index finger angular velocities from the low-pass filtered fluctuations of the amplitude of a plurality of EEG signals distributed across the scalp. To evaluate the accuracy of the decoder, the Pearson’s correlation coefficient (r between the observed and predicted trajectories was calculated in a 10-fold cross-validation scheme. We also assessed attempts to decode finger kinematics from EEG data that was cleaned with independent component analysis (ICA, EEG data from peripheral sensors, and EEG data from rest periods. A genetic algorithm was used to select combinations of EEG channels that maximized decoding accuracies. Our results (lower quartile r = 0.20, median r = 0.36, upper quartile r = 0.52 show that delta-band EEG signals contain useful information that can be used to infer finger kinematics. Further, the highest decoding accuracies were characterized by highly correlated delta band EEG activity mostly localized to the contralateral central areas of the scalp. Spectral analysis in alpha (8-13Hz and beta (20-30 Hz EEG respectively also showed focused bilateral alpha event related desynchronizations (ERDs over central scalp areas and contralateral beta event related synchronizations (ERSs localized to central scalp areas. Overall, this study demonstrates the feasibility of decoding finger kinematics from scalp EEG signals.

  9. Prior Knowledge Improves Decoding of Finger Flexion from Electrocorticographic (ECoG Signals

    Directory of Open Access Journals (Sweden)

    Zuoguan eWang

    2011-11-01

    Full Text Available Brain-computer interfaces (BCIs use brain signals to convey a user's intent. Some BCI approaches begin by decoding kinematic parameters of movements from brain signals, and then proceed to using these signals, in absence of movements, to allow a user to control an output. Recent results have shown that electrocorticographic (ECoG recordings from the surface of the brain in humans can give information about kinematic parameters (eg{} hand velocity or finger flexion. The decoding approaches in these studies usually employed classical classification/regression algorithms that derive a linear mapping between brain signals and outputs. However, they typically only incorporate little prior information about the target movement parameter. In this paper, we incorporate prior knowledge using a Bayesian decoding method, and use it to decode finger flexion from ECoG signals. Specifically, we exploit the anatomic constraints and dynamic constraints that govern finger flexion and incorporate these constraints in the construction, structure, and the probabilistic functions of the prior model of a switched non-parametric dynamic system (SNDS. Given a measurement model resulting from a traditional linear regression method, we decoded finger flexion using posterior estimation that combined the prior and measurement models. Our results show that the application of the Bayesian decoding model, which incorporates prior knowledge, improves decoding performance compared to the application of a linear regression model, which does not incorporate prior knowledge. Thus, the results presented in this paper may ultimately lead to neurally controlled hand prostheses with full fine-grained finger articulation.

  10. Decoding individual natural scene representations during perception and imagery

    Directory of Open Access Journals (Sweden)

    Matthew Robert Johnson

    2014-02-01

    Full Text Available We used a multi-voxel classification analysis of functional magnetic resonance imaging (fMRI data to determine to what extent item-specific information about complex natural scenes is represented in several category-selective areas of human extrastriate visual cortex during visual perception and visual mental imagery. Participants in the scanner either viewed or were instructed to visualize previously memorized natural scene exemplars, and the neuroimaging data were subsequently subjected to a multi-voxel pattern analysis (MVPA using a support vector machine (SVM classifier. We found that item-specific information was represented in multiple scene-selective areas: the occipital place area (OPA, parahippocampal place area (PPA, retrosplenial cortex (RSC, and a scene-selective portion of the precuneus/intraparietal sulcus region (PCu/IPS. Furthermore, item-specific information from perceived scenes was re-instantiated during mental imagery of the same scenes. These results support findings from previous decoding analyses for other types of visual information and/or brain areas during imagery or working memory, and extend them to the case of visual scenes (and scene-selective cortex. Taken together, such findings support models suggesting that reflective mental processes are subserved by the re-instantiation of perceptual information in high-level visual cortex. We also examined activity in the fusiform face area (FFA and found that it, too, contained significant item-specific scene information during perception, but not during mental imagery. This suggests that although decodable scene-relevant activity occurs in FFA during perception, FFA activity may not be a necessary (or even relevant component of one’s mental representation of visual scenes.

  11. Decoding the Locus of Covert Visuospatial Attention from EEG Signals.

    Directory of Open Access Journals (Sweden)

    Thomas Thiery

    Full Text Available Visuospatial attention can be deployed to different locations in space independently of ocular fixation, and studies have shown that event-related potential (ERP components can effectively index whether such covert visuospatial attention is deployed to the left or right visual field. However, it is not clear whether we may obtain a more precise spatial localization of the focus of attention based on the EEG signals during central fixation. In this study, we used a modified Posner cueing task with an endogenous cue to determine the degree to which information in the EEG signal can be used to track visual spatial attention in presentation sequences lasting 200 ms. We used a machine learning classification method to evaluate how well EEG signals discriminate between four different locations of the focus of attention. We then used a multi-class support vector machine (SVM and a leave-one-out cross-validation framework to evaluate the decoding accuracy (DA. We found that ERP-based features from occipital and parietal regions showed a statistically significant valid prediction of the location of the focus of visuospatial attention (DA = 57%, p < .001, chance-level 25%. The mean distance between the predicted and the true focus of attention was 0.62 letter positions, which represented a mean error of 0.55 degrees of visual angle. In addition, ERP responses also successfully predicted whether spatial attention was allocated or not to a given location with an accuracy of 79% (p < .001. These findings are discussed in terms of their implications for visuospatial attention decoding and future paths for research are proposed.

  12. Broadband Prosthetic Interfaces: Combining Nerve Transfers and Implantable Multichannel EMG Technology to Decode Spinal Motor Neuron Activity

    Directory of Open Access Journals (Sweden)

    Konstantin D. Bergmeister

    2017-07-01

    Full Text Available Modern robotic hands/upper limbs may replace multiple degrees of freedom of extremity function. However, their intuitive use requires a high number of control signals, which current man-machine interfaces do not provide. Here, we discuss a broadband control interface that combines targeted muscle reinnervation, implantable multichannel electromyographic sensors, and advanced decoding to address the increasing capabilities of modern robotic limbs. With targeted muscle reinnervation, nerves that have lost their targets due to an amputation are surgically transferred to residual stump muscles to increase the number of intuitive prosthetic control signals. This surgery re-establishes a nerve-muscle connection that is used for sensing nerve activity with myoelectric interfaces. Moreover, the nerve transfer determines neurophysiological effects, such as muscular hyper-reinnervation and cortical reafferentation that can be exploited by the myoelectric interface. Modern implantable multichannel EMG sensors provide signals from which it is possible to disentangle the behavior of single motor neurons. Recent studies have shown that the neural drive to muscles can be decoded from these signals and thereby the user's intention can be reliably estimated. By combining these concepts in chronic implants and embedded electronics, we believe that it is in principle possible to establish a broadband man-machine interface, with specific applications in prosthesis control. This perspective illustrates this concept, based on combining advanced surgical techniques with recording hardware and processing algorithms. Here we describe the scientific evidence for this concept, current state of investigations, challenges, and alternative approaches to improve current prosthetic interfaces.

  13. Sum-Rate Enhancement in Multiuser MIMO Decode-and-Forward Relay Broadcasting Channel with Energy Harvesting Relays

    KAUST Repository

    Benkhelifa, Fatma

    2016-09-20

    In this paper, we consider a multiuser multipleinput multiple-output (MIMO) decode-and-forward (DF) relay broadcasting channel (BC) with single source, multiple energy harvesting (EH) relays and multiple destinations. All the nodes are equipped with multiple antennas. The EH and information decoding (ID) tasks at the relays and destinations are separated over the time, which is termed as the time switching (TS) scheme. As optimal solutions for the sum-rate maximization problems of BC channels and the MIMO interference channels are hard to obtain, the end-to-end sum rate maximization problem of a multiuser MIMO DF relay BC channel is even harder. In this paper, we propose to tackle a simplified problem where we employ the block diagonalization (BD) procedure at the source, and we mitigate the interference between the relaydestination channels using an algorithm similar to the BD method. In order to show the relevance of our low complex proposed solution, we compare it to the minimum mean-square error (MMSE) solution that was shown in the literature to be equivalent to the solution of the sum-rate maximization in MIMO broadcasting interfering channels. We also investigate the time division multiple access (TDMA) solution which separates all the information transmissions from the source to the relays and from the relays to the destinations over time. We provide numerical results to show the relevance of our proposed solution, in comparison with the no co-channel interference (CCI) case, the TDMA based solution and the MMSE based solution.

  14. A best-first soft/hard decision tree searching MIMO decoder for a 4 × 4 64-QAM system

    KAUST Repository

    Shen, Chungan

    2012-08-01

    This paper presents the algorithm and VLSI architecture of a configurable tree-searching approach that combines the features of classical depth-first and breadth-first methods. Based on this approach, techniques to reduce complexity while providing both hard and soft outputs decoding are presented. Furthermore, a single programmable parameter allows the user to tradeoff throughput versus BER performance. The proposed multiple-input-multiple-output decoder supports a 4 × 4 64-QAM system and was synthesized with 65-nm CMOS technology at 333 MHz clock frequency. For the hard output scheme the design can achieve an average throughput of 257.8 Mbps at 24 dB signal-to-noise ratio (SNR) with area equivalent to 54.2 Kgates and a power consumption of 7.26 mW. For the soft output scheme it achieves an average throughput of 83.3 Mbps across the SNR range of interest with an area equivalent to 64 Kgates and a power consumption of 11.5 mW. © 2011 IEEE.

  15. Grounding word learning in space.

    Directory of Open Access Journals (Sweden)

    Larissa K Samuelson

    Full Text Available Humans and objects, and thus social interactions about objects, exist within space. Words direct listeners' attention to specific regions of space. Thus, a strong correspondence exists between where one looks, one's bodily orientation, and what one sees. This leads to further correspondence with what one remembers. Here, we present data suggesting that children use associations between space and objects and space and words to link words and objects--space binds labels to their referents. We tested this claim in four experiments, showing that the spatial consistency of where objects are presented affects children's word learning. Next, we demonstrate that a process model that grounds word learning in the known neural dynamics of spatial attention, spatial memory, and associative learning can capture the suite of results reported here. This model also predicts that space is special, a prediction supported in a fifth experiment that shows children do not use color as a cue to bind words and objects. In a final experiment, we ask whether spatial consistency affects word learning in naturalistic word learning contexts. Children of parents who spontaneously keep objects in a consistent spatial location during naming interactions learn words more effectively. Together, the model and data show that space is a powerful tool that can effectively ground word learning in social contexts.

  16. Stress Judgment and Production in English Derivation, and Word Reading in Adult Mandarin-Speaking English Learners.

    Science.gov (United States)

    Chung, Wei-Lun; Jarmulowicz, Linda

    2017-08-01

    For monolingual English-speaking children, judgment and production of stress in derived words, including words with phonologically neutral (e.g., -ness) and non-neutral suffixes (e.g., -ity), is important to both academic vocabulary growth and to word reading. For Mandarin-speaking adult English learners (AELs) the challenge of learning the English stress system might be complicated by cross-linguistic differences in prosodic function and features. As Mandarin-speakers become more proficient in English, patterns similar to those seen in monolingual children could emerge in which awareness and use of stress and suffix cues benefit word reading. A correlational design was used to examine the contributions of English stress in derivation with neutral and non-neutral suffixes to English word and nonword reading. Stress judgment in non-neutral derivation predicted word reading after controlling for working memory and English vocabulary; whereas stress production in neutral derivation contributed to word reading and pseudoword decoding, independent of working memory and English vocabulary. Although AELs could use stress and suffix cues for word reading, AELs were different from native English speakers in awareness of non-neutral suffix cues conditioning lexical stress placement. AELs may need to rely on lexical storage of primary stress in derivations with non-neutral suffixes.

  17. Estimating affective word covariates using word association data.

    Science.gov (United States)

    Van Rensbergen, Bram; De Deyne, Simon; Storms, Gert

    2016-12-01

    Word ratings on affective dimensions are an important tool in psycholinguistic research. Traditionally, they are obtained by asking participants to rate words on each dimension, a time-consuming procedure. As such, there has been some interest in computationally generating norms, by extrapolating words' affective ratings using their semantic similarity to words for which these values are already known. So far, most attempts have derived similarity from word co-occurrence in text corpora. In the current paper, we obtain similarity from word association data. We use these similarity ratings to predict the valence, arousal, and dominance of 14,000 Dutch words with the help of two extrapolation methods: Orientation towards Paradigm Words and k-Nearest Neighbors. The resulting estimates show very high correlations with human ratings when using Orientation towards Paradigm Words, and even higher correlations when using k-Nearest Neighbors. We discuss possible theoretical accounts of our results and compare our findings with previous attempts at computationally generating affective norms.

  18. Semantic and associative factors in probability learning with words.

    Science.gov (United States)

    Schipper, L M; Hanson, B L; Taylor, G; Thorpe, J A

    1973-09-01

    Using a probability-learning technique with a single word as the cue and with the probability of a given event following this word fixed at .80, it was found (1) that neither high nor low associates to the original word and (2) that neither synonyms nor antonyms showed differential learning curves subsequent to original learning when the probability for the following event was shifted to .20. In a second study when feedback, in the form of knowledge of results, was withheld, there was a clear-cut similarity of predictions to the originally trained word and the synonyms of both high and low association value and a dissimilarity of these words to a set of antonyms of both high and low association value. Two additional studies confirmed the importance of the semantic dimension as compared with association value as traditionally measured.

  19. Reward value is encoded in primary somatosensory cortex and can be decoded from neural activity during performance of a psychophysical task.

    Science.gov (United States)

    McNiel, David B; Choi, John S; Hessburg, John P; Francis, Joseph T

    2016-08-01

    Encoding of reward valence has been shown in various brain regions, including deep structures such as the substantia nigra as well as cortical structures such as the orbitofrontal cortex. While the correlation between these signals and reward valence have been shown in aggregated data comprised of many trials, little work has been done investigating the feasibility of decoding reward valence on a single trial basis. Towards this goal, one non-human primate (macaca radiata) was trained to grip and hold a target level of force in order to earn zero, one, two, or three juice rewards. The animal was informed of the impending result before reward delivery by means of a visual cue. Neural data was recorded from primary somatosensory cortex (S1) during these experiments and firing rate histograms were created following the appearance of the visual cue and used as input to a variety of classifiers. Reward valence was decoded with high levels of accuracy from S1 both in the post-cue and post-reward periods. Additionally, the proportion of units showing significant changes in their firing rates was influenced in a predictable way based on reward valence. The existence of a signal within S1 cortex that encodes reward valence could have utility for implementing reinforcement learning algorithms for brain machine interfaces. The ability to decode this reward signal in real time with limited data is paramount to the usability of such a signal in practical applications.

  20. Electronic Word of Behavior

    DEFF Research Database (Denmark)

    Kunst, Katrine; Vatrapu, Ravi; Hussain, Abid

    2017-01-01

    In this research in progress-paper, we introduce the notion of ‘Electronic Word of Behavior’ (eWOB) to describe the phenomenon of consumers’ product-related behaviors increasingly made observable by online social environments. We employ Observational Learning theory to conceptualize the notion of e......WOB and generate hypotheses about how consumers influence each other by means of behavior in online social environments. We present a conceptual framework for categorizing eWOB, and propose a novel research design for a randomized controlled field experiment. Specifically, the ongoing experiment aims to analyze...... how the presence of individual-specific behavior-based social information in a movie streaming service affects potential users’ attitude towards and intentions to use the service....