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Sample records for target word recognition

  1. A Comparison of Two Flashcard Drill Methods Targeting Word Recognition

    ERIC Educational Resources Information Center

    Volpe, Robert J.; Mule, Christina M.; Briesch, Amy M.; Joseph, Laurice M.; Burns, Matthew K.

    2011-01-01

    Traditional drill and practice (TD) and incremental rehearsal (IR) are two flashcard drill instructional methods previously noted to improve word recognition. The current study sought to compare the effectiveness and efficiency of these two methods, as assessed by next day retention assessments, under 2 conditions (i.e., opportunities to respond…

  2. Units of Word Recognition.

    ERIC Educational Resources Information Center

    Santa, Carol M.; And Others

    Both psychologists and reading specialists have been interested in whether words are processed letter by letter or in larger units. A reaction time paradigm was used to evaluate these options with interest focused on potential units of word recognition which might be functional within single syllable words. The basic paradigm involved presenting…

  3. Word Recognition in Auditory Cortex

    ERIC Educational Resources Information Center

    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. Sign Facilitation in Word Recognition.

    ERIC Educational Resources Information Center

    Wauters, Loes N.; Knoors, Harry E. T.; Vervloed, Mathijs P. J.; Aarnoutse, Cor A. J.

    2001-01-01

    This study examined whether use of sign language would facilitate reading word recognition by 16 deaf children (6- to 1 years-old) in the Netherlands. Results indicated that if words were learned through speech, accompanied by the relevant sign, accuracy of word recognition was greater than if words were learned solely through speech. (Contains…

  5. Word recognition using ideal word patterns

    NASA Astrophysics Data System (ADS)

    Zhao, Sheila X.; Srihari, Sargur N.

    1994-03-01

    The word shape analysis approach to text recognition is motivated by discoveries in psychological studies of the human reading process. It attempts to describe and compare the shape of the word as a whole object without trying to segment and recognize the individual characters, so it bypasses the errors committed in character segmentation and classification. However, the large number of classes and large variation and distortion expected in all patterns belonging to the same class make it difficult for conventional, accurate, pattern recognition approaches. A word shape analysis approach using ideal word patterns to overcome the difficulty and improve recognition performance is described in this paper. A special word pattern which characterizes a word class is extracted from different sample patterns of the word class and stored in memory. Recognition of a new word pattern is achieved by comparing it with the special pattern of each word class called ideal word pattern. The process of generating the ideal word pattern of each word class is proposed. The algorithm was tested on a set of machine printed gray scale word images which included a wide range of print types and qualities.

  6. Word Recognition and Critical Reading.

    ERIC Educational Resources Information Center

    Groff, Patrick

    1991-01-01

    This article discusses the distinctions between literal and critical reading and explains the role that word recognition ability plays in critical reading behavior. It concludes that correct word recognition provides the raw material on which higher order critical reading is based. (DB)

  7. The recognition potential and word priming.

    PubMed

    Rudell, A P; Hua, J

    1996-11-01

    The effect of priming on the latency of the recognition potential (RP) was tested using rapid stream stimulation. Subjects detected five-letter words in a stream of nonword images. Lifting the right index finger signalled detection of a word. Rapid responses were rewarded and false alarms were penalized. Just before generating an image stream, a computer briefly displayed either the specific target word or or five-letter string that indicated the target was any one of ten previously studied words. Precise target specification was expected to produce more rapid detection than the provision of less definite information. Since the RP was thought to reflect the speed of perception, it was predicted that its latency would be less when the target word was beforehand than when less specific information was provided. The results for 10 subjects confirmed the hypothesis.

  8. Bilingual word recognition in a sentence context.

    PubMed

    Assche, Eva Van; Duyck, Wouter; Hartsuiker, Robert J

    2012-01-01

    This article provides an overview of bilingualism research on visual word recognition in isolation and in sentence context. Many studies investigating the processing of words out-of-context have shown that lexical representations from both languages are activated when reading in one language (language-non-selective lexical access). A newly developed research line asks whether language-non-selective access generalizes to word recognition in sentence contexts, providing a language cue and/or semantic constraint information for upcoming words. Recent studies suggest that the language of the preceding words is insufficient to restrict lexical access to words of the target language, even when reading in the native language. Eye tracking studies revealing the time course of word activation further showed that semantic constraint does not restrict language-non-selective access at early reading stages, but there is evidence that it has a relatively late effect. The theoretical implications for theories of bilingual word recognition are discussed in light of the Bilingual Interactive Activation+ model (Dijkstra and van Heuven, 2002).

  9. Visual recognition of permuted words

    NASA Astrophysics Data System (ADS)

    Rashid, Sheikh Faisal; Shafait, Faisal; Breuel, Thomas M.

    2010-02-01

    In current study we examine how letter permutation affects in visual recognition of words for two orthographically dissimilar languages, Urdu and German. We present the hypothesis that recognition or reading of permuted and non-permuted words are two distinct mental level processes, and that people use different strategies in handling permuted words as compared to normal words. A comparison between reading behavior of people in these languages is also presented. We present our study in context of dual route theories of reading and it is observed that the dual-route theory is consistent with explanation of our hypothesis of distinction in underlying cognitive behavior for reading permuted and non-permuted words. We conducted three experiments in lexical decision tasks to analyze how reading is degraded or affected by letter permutation. We performed analysis of variance (ANOVA), distribution free rank test, and t-test to determine the significance differences in response time latencies for two classes of data. Results showed that the recognition accuracy for permuted words is decreased 31% in case of Urdu and 11% in case of German language. We also found a considerable difference in reading behavior for cursive and alphabetic languages and it is observed that reading of Urdu is comparatively slower than reading of German due to characteristics of cursive script.

  10. Cortical dynamics of word recognition.

    PubMed

    Mainy, Nelly; Jung, Julien; Baciu, Monica; Kahane, Philippe; Schoendorff, Benjamin; Minotti, Lorella; Hoffmann, Dominique; Bertrand, Olivier; Lachaux, Jean-Philippe

    2008-11-01

    While functional neuroimaging studies have helped elucidate major regions implicated in word recognition, much less is known about the dynamics of the associated activations or the actual neural processes of their functional network. We used intracerebral electroencephalography recordings in 10 patients with epilepsy to directly measure neural activity in the temporal and frontal lobes during written words' recognition, predominantly in the left hemisphere. The patients were presented visually with consonant strings, pseudo-words, and words and performed a hierarchical paradigm contrasting semantic processes (living vs. nonliving word categorization task), phonological processes (rhyme decision task on pseudo-words), and visual processes (visual analysis of consonant strings). Stimuli triggered a cascade of modulations in the gamma-band (>40 Hz) with reproducible timing and task-sensitivity throughout the functional reading network: the earliest gamma-band activations were observed for all stimuli in the mesial basal temporal lobe at 150 ms, reaching the word form area in the mid fusiform gyrus at 200 ms, evidencing a superiority effect for word-like stimuli. Peaks of gamma-band activations were then observed for word-like stimuli after 400 ms in the anterior and middle portion of the superior temporal gyrus (BA 38 and BA 22 respectively), in the pars triangularis of Broca's area for the semantic task (BAs 45 and 47), and in the pars opercularis for the phonological task (BA 44). Concurrently, we observed a two-pronged effect in the prefrontal cortex (BAs 9 and 46), with nonspecific sustained dorsal activation related to sustained attention and, more ventrally, a strong reflex deactivation around 500 ms, possibly due to semantic working memory reset. PMID:17712785

  11. Adult Word Recognition and Visual Sequential Memory

    ERIC Educational Resources Information Center

    Holmes, V. M.

    2012-01-01

    Two experiments were conducted investigating the role of visual sequential memory skill in the word recognition efficiency of undergraduate university students. Word recognition was assessed in a lexical decision task using regularly and strangely spelt words, and nonwords that were either standard orthographically legal strings or items made from…

  12. Sonority contours in word recognition

    NASA Astrophysics Data System (ADS)

    McLennan, Sean

    2003-04-01

    Contrary to the Generativist distinction between competence and performance which asserts that speech or perception errors are due to random, nonlinguistic factors, it seems likely that errors are principled and possibly governed by some of the same constraints as language. A preliminary investigation of errors modeled after the child's ``Chain Whisper'' game (a degraded stimulus task) suggests that a significant number of recognition errors can be characterized as an improvement in syllable sonority contour towards the linguistically least-marked, voiceless-stop-plus-vowel syllable. An independent study of sonority contours showed that approximately half of the English lexicon can be uniquely identified by their contour alone. Additionally, ``sororities'' (groups of words that share a single sonority contour), surprisingly, show no correlation to familiarity or frequency in either size or membership. Together these results imply that sonority contours may be an important factor in word recognition and in defining word ``neighborhoods.'' Moreover, they suggest that linguistic markedness constraints may be more prevalent in performance-related phenomena than previously accepted.

  13. Embedded Words in Visual Word Recognition: Does the Left Hemisphere See the Rain in Brain?

    ERIC Educational Resources Information Center

    McCormick, Samantha F.; Davis, Colin J.; Brysbaert, Marc

    2010-01-01

    To examine whether interhemispheric transfer during foveal word recognition entails a discontinuity between the information presented to the left and right of fixation, we presented target words in such a way that participants fixated immediately left or right of an embedded word (as in "gr*apple", "bull*et") or in the middle of an embedded word…

  14. Acquired prosopagnosia without word recognition deficits.

    PubMed

    Susilo, Tirta; Wright, Victoria; Tree, Jeremy J; Duchaine, Bradley

    2015-01-01

    It has long been suggested that face recognition relies on specialized mechanisms that are not involved in visual recognition of other object categories, including those that require expert, fine-grained discrimination at the exemplar level such as written words. But according to the recently proposed many-to-many theory of object recognition (MTMT), visual recognition of faces and words are carried out by common mechanisms [Behrmann, M., & Plaut, D. C. ( 2013 ). Distributed circuits, not circumscribed centers, mediate visual recognition. Trends in Cognitive Sciences, 17, 210-219]. MTMT acknowledges that face and word recognition are lateralized, but posits that the mechanisms that predominantly carry out face recognition still contribute to word recognition and vice versa. MTMT makes a key prediction, namely that acquired prosopagnosics should exhibit some measure of word recognition deficits. We tested this prediction by assessing written word recognition in five acquired prosopagnosic patients. Four patients had lesions limited to the right hemisphere while one had bilateral lesions with more pronounced lesions in the right hemisphere. The patients completed a total of seven word recognition tasks: two lexical decision tasks and five reading aloud tasks totalling more than 1200 trials. The performances of the four older patients (3 female, age range 50-64 years) were compared to those of 12 older controls (8 female, age range 56-66 years), while the performances of the younger prosopagnosic (male, 31 years) were compared to those of 14 younger controls (9 female, age range 20-33 years). We analysed all results at the single-patient level using Crawford's t-test. Across seven tasks, four prosopagnosics performed as quickly and accurately as controls. Our results demonstrate that acquired prosopagnosia can exist without word recognition deficits. These findings are inconsistent with a key prediction of MTMT. They instead support the hypothesis that face

  15. Acquired prosopagnosia without word recognition deficits.

    PubMed

    Susilo, Tirta; Wright, Victoria; Tree, Jeremy J; Duchaine, Bradley

    2015-01-01

    It has long been suggested that face recognition relies on specialized mechanisms that are not involved in visual recognition of other object categories, including those that require expert, fine-grained discrimination at the exemplar level such as written words. But according to the recently proposed many-to-many theory of object recognition (MTMT), visual recognition of faces and words are carried out by common mechanisms [Behrmann, M., & Plaut, D. C. ( 2013 ). Distributed circuits, not circumscribed centers, mediate visual recognition. Trends in Cognitive Sciences, 17, 210-219]. MTMT acknowledges that face and word recognition are lateralized, but posits that the mechanisms that predominantly carry out face recognition still contribute to word recognition and vice versa. MTMT makes a key prediction, namely that acquired prosopagnosics should exhibit some measure of word recognition deficits. We tested this prediction by assessing written word recognition in five acquired prosopagnosic patients. Four patients had lesions limited to the right hemisphere while one had bilateral lesions with more pronounced lesions in the right hemisphere. The patients completed a total of seven word recognition tasks: two lexical decision tasks and five reading aloud tasks totalling more than 1200 trials. The performances of the four older patients (3 female, age range 50-64 years) were compared to those of 12 older controls (8 female, age range 56-66 years), while the performances of the younger prosopagnosic (male, 31 years) were compared to those of 14 younger controls (9 female, age range 20-33 years). We analysed all results at the single-patient level using Crawford's t-test. Across seven tasks, four prosopagnosics performed as quickly and accurately as controls. Our results demonstrate that acquired prosopagnosia can exist without word recognition deficits. These findings are inconsistent with a key prediction of MTMT. They instead support the hypothesis that face

  16. Syllable Transposition Effects in Korean Word Recognition

    ERIC Educational Resources Information Center

    Lee, Chang H.; Kwon, Youan; Kim, Kyungil; Rastle, Kathleen

    2015-01-01

    Research on the impact of letter transpositions in visual word recognition has yielded important clues about the nature of orthographic representations. This study investigated the impact of syllable transpositions on the recognition of Korean multisyllabic words. Results showed that rejection latencies in visual lexical decision for…

  17. The Slow Developmental Time Course of Real-Time Spoken Word Recognition

    ERIC Educational Resources Information Center

    Rigler, Hannah; Farris-Trimble, Ashley; Greiner, Lea; Walker, Jessica; Tomblin, J. Bruce; McMurray, Bob

    2015-01-01

    This study investigated the developmental time course of spoken word recognition in older children using eye tracking to assess how the real-time processing dynamics of word recognition change over development. We found that 9-year-olds were slower to activate the target words and showed more early competition from competitor words than…

  18. Word-Recognition Training: Computer versus Tutor

    ERIC Educational Resources Information Center

    Lewandowski, Lawrence; Begeny, John; Rogers, Cynthia

    2006-01-01

    The effects of tutor- or computer-assisted word recognition were assessed in a sample of third grade children. At pre-test, students' reading accuracy and fluency were evaluated on a training word list, generalization word list, and reading passages. Students were then randomly assigned to one of three group conditions--control (students practiced…

  19. Item Effects in Recognition Memory for Words

    ERIC Educational Resources Information Center

    Freeman, Emily; Heathcote, Andrew; Chalmers, Kerry; Hockley, William

    2010-01-01

    We investigate the effects of word characteristics on episodic recognition memory using analyses that avoid Clark's (1973) "language-as-a-fixed-effect" fallacy. Our results demonstrate the importance of modeling word variability and show that episodic memory for words is strongly affected by item noise (Criss & Shiffrin, 2004), as measured by the…

  20. Task-Dependent Masked Priming Effects in Visual Word Recognition

    PubMed Central

    Kinoshita, Sachiko; Norris, Dennis

    2012-01-01

    A method used widely to study the first 250 ms of visual word recognition is masked priming: These studies have yielded a rich set of data concerning the processes involved in recognizing letters and words. In these studies, there is an implicit assumption that the early processes in word recognition tapped by masked priming are automatic, and masked priming effects should therefore be invariant across tasks. Contrary to this assumption, masked priming effects are modulated by the task goal: For example, only word targets show priming in the lexical decision task, but both words and non-words do in the same-different task; semantic priming effects are generally weak in the lexical decision task but are robust in the semantic categorization task. We explain how such task dependence arises within the Bayesian Reader account of masked priming (Norris and Kinoshita, 2008), and how the task dissociations can be used to understand the early processes in lexical access. PMID:22675316

  1. Lexical Competition in Non-Native Spoken-Word Recognition

    ERIC Educational Resources Information Center

    Weber, Andrea; Cutler, Anne

    2004-01-01

    Four eye-tracking experiments examined lexical competition in non-native spoken-word recognition. Dutch listeners hearing English fixated longer on distractor pictures with names containing vowels that Dutch listeners are likely to confuse with vowels in a target picture name ("pencil," given target "panda") than on less confusable distractors…

  2. Individual differences in online spoken word recognition: Implications for SLI.

    PubMed

    McMurray, Bob; Samelson, Vicki M; Lee, Sung Hee; Tomblin, J Bruce

    2010-02-01

    Thirty years of research has uncovered the broad principles that characterize spoken word processing across listeners. However, there have been few systematic investigations of individual differences. Such an investigation could help refine models of word recognition by indicating which processing parameters are likely to vary, and could also have important implications for work on language impairment. The present study begins to fill this gap by relating individual differences in overall language ability to variation in online word recognition processes. Using the visual world paradigm, we evaluated online spoken word recognition in adolescents who varied in both basic language abilities and non-verbal cognitive abilities. Eye movements to target, cohort and rhyme objects were monitored during spoken word recognition, as an index of lexical activation. Adolescents with poor language skills showed fewer looks to the target and more fixations to the cohort and rhyme competitors. These results were compared to a number of variants of the TRACE model (McClelland & Elman, 1986) that were constructed to test a range of theoretical approaches to language impairment: impairments at sensory and phonological levels; vocabulary size, and generalized slowing. None of the existing approaches were strongly supported, and variation in lexical decay offered the best fit. Thus, basic word recognition processes like lexical decay may offer a new way to characterize processing differences in language impairment. PMID:19836014

  3. Individual differences in online spoken word recognition: Implications for SLI

    PubMed Central

    McMurray, Bob; Samelson, Vicki M.; Lee, Sung Hee; Tomblin, J. Bruce

    2012-01-01

    Thirty years of research has uncovered the broad principles that characterize spoken word processing across listeners. However, there have been few systematic investigations of individual differences. Such an investigation could help refine models of word recognition by indicating which processing parameters are likely to vary, and could also have important implications for work on language impairment. The present study begins to fill this gap by relating individual differences in overall language ability to variation in online word recognition processes. Using the visual world paradigm, we evaluated online spoken word recognition in adolescents who varied in both basic language abilities and non-verbal cognitive abilities. Eye movements to target, cohort and rhyme objects were monitored during spoken word recognition, as an index of lexical activation. Adolescents with poor language skills showed fewer looks to the target and more fixations to the cohort and rhyme competitors. These results were compared to a number of variants of the TRACE model (McClelland & Elman, 1986) that were constructed to test a range of theoretical approaches to language impairment: impairments at sensory and phonological levels; vocabulary size, and generalized slowing. None were strongly supported, and variation in lexical decay offered the best fit. Thus, basic word recognition processes like lexical decay may offer a new way to characterize processing differences in language impairment. PMID:19836014

  4. Early Word Recognition and Later Language Skills

    PubMed Central

    Junge, Caroline; Cutler, Anne

    2014-01-01

    Recent behavioral and electrophysiological evidence has highlighted the long-term importance for language skills of an early ability to recognize words in continuous speech. We here present further tests of this long-term link in the form of follow-up studies conducted with two (separate) groups of infants who had earlier participated in speech segmentation tasks. Each study extends prior follow-up tests: Study 1 by using a novel follow-up measure that taps into online processing, Study 2 by assessing language performance relationships over a longer time span than previously tested. Results of Study 1 show that brain correlates of speech segmentation ability at 10 months are positively related to 16-month-olds’ target fixations in a looking-while-listening task. Results of Study 2 show that infant speech segmentation ability no longer directly predicts language profiles at the age of five. However, a meta-analysis across our results and those of similar studies (Study 3) reveals that age at follow-up does not moderate effect size. Together, the results suggest that infants’ ability to recognize words in speech certainly benefits early vocabulary development; further observed relationships of later language skills to early word recognition may be consequent upon this vocabulary size effect. PMID:25347057

  5. The Activation of Embedded Words in Spoken Word Recognition

    PubMed Central

    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

  6. Famous talker effects in spoken word recognition.

    PubMed

    Maibauer, Alisa M; Markis, Teresa A; Newell, Jessica; McLennan, Conor T

    2014-01-01

    Previous work has demonstrated that talker-specific representations affect spoken word recognition relatively late during processing. However, participants in these studies were listening to unfamiliar talkers. In the present research, we used a long-term repetition-priming paradigm and a speeded-shadowing task and presented listeners with famous talkers. In Experiment 1, half the words were spoken by Barack Obama, and half by Hillary Clinton. Reaction times (RTs) to repeated words were shorter than those to unprimed words only when repeated by the same talker. However, in Experiment 2, using nonfamous talkers, RTs to repeated words were shorter than those to unprimed words both when repeated by the same talker and when repeated by a different talker. Taken together, the results demonstrate that talker-specific details can affect the perception of spoken words relatively early during processing when words are spoken by famous talkers.

  7. Famous talker effects in spoken word recognition.

    PubMed

    Maibauer, Alisa M; Markis, Teresa A; Newell, Jessica; McLennan, Conor T

    2014-01-01

    Previous work has demonstrated that talker-specific representations affect spoken word recognition relatively late during processing. However, participants in these studies were listening to unfamiliar talkers. In the present research, we used a long-term repetition-priming paradigm and a speeded-shadowing task and presented listeners with famous talkers. In Experiment 1, half the words were spoken by Barack Obama, and half by Hillary Clinton. Reaction times (RTs) to repeated words were shorter than those to unprimed words only when repeated by the same talker. However, in Experiment 2, using nonfamous talkers, RTs to repeated words were shorter than those to unprimed words both when repeated by the same talker and when repeated by a different talker. Taken together, the results demonstrate that talker-specific details can affect the perception of spoken words relatively early during processing when words are spoken by famous talkers. PMID:24366633

  8. Models of spoken-word recognition.

    PubMed

    Weber, Andrea; Scharenborg, Odette

    2012-05-01

    All words of the languages we know are stored in the mental lexicon. Psycholinguistic models describe in which format lexical knowledge is stored and how it is accessed when needed for language use. The present article summarizes key findings in spoken-word recognition by humans and describes how models of spoken-word recognition account for them. Although current models of spoken-word recognition differ considerably in the details of implementation, there is general consensus among them on at least three aspects: multiple word candidates are activated in parallel as a word is being heard, activation of word candidates varies with the degree of match between the speech signal and stored lexical representations, and activated candidate words compete for recognition. No consensus has been reached on other aspects such as the flow of information between different processing levels, and the format of stored prelexical and lexical representations. WIREs Cogn Sci 2012, 3:387-401. doi: 10.1002/wcs.1178 For further resources related to this article, please visit the WIREs website.

  9. Sign and Word Recognition: A First Comparison.

    ERIC Educational Resources Information Center

    Grosjean, Francois

    1981-01-01

    The results of a word recognition study are compared to those of a sign recognition study in order to determine which aspects of lexical access are comparable in speech and sign, and which are specific to each of the two language modalities. The "gating paradigm" was used in both studies. (Author/AMH)

  10. Immediate effects of anticipatory coarticulation in spoken-word recognition

    PubMed Central

    Salverda, Anne Pier; Kleinschmidt, Dave; Tanenhaus, Michael K.

    2014-01-01

    Two visual-world experiments examined listeners’ use of pre word-onset anticipatory coarticulation in spoken-word recognition. Experiment 1 established the shortest lag with which information in the speech signal influences eye-movement control, using stimuli such as “The … ladder is the target”. With a neutral token of the definite article preceding the target word, saccades to the referent were not more likely than saccades to an unrelated distractor until 200–240 ms after the onset of the target word. In Experiment 2, utterances contained definite articles which contained natural anticipatory coarticulation pertaining to the onset of the target word (“ The ladder … is the target”). A simple Gaussian classifier was able to predict the initial sound of the upcoming target word from formant information from the first few pitch periods of the article’s vowel. With these stimuli, effects of speech on eye-movement control began about 70 ms earlier than in Experiment 1, suggesting rapid use of anticipatory coarticulation. The results are interpreted as support for “data explanation” approaches to spoken-word recognition. Methodological implications for visual-world studies are also discussed. PMID:24511179

  11. The spread of the phonological neighborhood influences spoken word recognition

    PubMed Central

    Vitevitch, Michael S.

    2008-01-01

    In three experiments, the processing of words that had the same overall number of neighbors but varied in the spread of the neighborhood (i.e., the number of individual phonemes that could be changed to form real words) was examined. In an auditory lexical decision task, a naming task, and a same–different task, words in which changes at only two phoneme positions formed neighbors were responded to more quickly than words in which changes at all three phoneme positions formed neighbors. Additional analyses ruled out an account based on the computationally derived uniqueness points of the words. Although previous studies (e.g., Luce & Pisoni, 1998) have shown that the number of phonological neighbors influences spoken word recognition, the present results show that the nature of the relationship of the neighbors to the target word—as measured by the spread of the neighborhood—also influences spoken word recognition. The implications of this result for models of spoken word recognition are discussed. PMID:17533890

  12. Spoken Word Recognition of Chinese Words in Continuous Speech

    ERIC Educational Resources Information Center

    Yip, Michael C. W.

    2015-01-01

    The present study examined the role of positional probability of syllables played in recognition of spoken word in continuous Cantonese speech. Because some sounds occur more frequently at the beginning position or ending position of Cantonese syllables than the others, so these kinds of probabilistic information of syllables may cue the locations…

  13. The Army word recognition system

    NASA Technical Reports Server (NTRS)

    Hadden, David R.; Haratz, David

    1977-01-01

    The application of speech recognition technology in the Army command and control area is presented. The problems associated with this program are described as well as as its relevance in terms of the man/machine interactions, voice inflexions, and the amount of training needed to interact with and utilize the automated system.

  14. Word Recognition: Theoretical Issues and Instructional Hints.

    ERIC Educational Resources Information Center

    Smith, Edward E.; Kleiman, Glenn M.

    Research on adult readers' word recognition skills is used in this paper to develop a general information processing model of reading. Stages of the model include feature extraction, interpretation, lexical access, working memory, and integration. Of those stages, particular attention is given to the units of interpretation, speech recoding and…

  15. Infant word recognition: Insights from TRACE simulations☆

    PubMed Central

    Mayor, Julien; Plunkett, Kim

    2014-01-01

    The TRACE model of speech perception (McClelland & Elman, 1986) is used to simulate results from the infant word recognition literature, to provide a unified, theoretical framework for interpreting these findings. In a first set of simulations, we demonstrate how TRACE can reconcile apparently conflicting findings suggesting, on the one hand, that consonants play a pre-eminent role in lexical acquisition (Nespor, Peña & Mehler, 2003; Nazzi, 2005), and on the other, that there is a symmetry in infant sensitivity to vowel and consonant mispronunciations of familiar words (Mani & Plunkett, 2007). In a second series of simulations, we use TRACE to simulate infants’ graded sensitivity to mispronunciations of familiar words as reported by White and Morgan (2008). An unexpected outcome is that TRACE fails to demonstrate graded sensitivity for White and Morgan’s stimuli unless the inhibitory parameters in TRACE are substantially reduced. We explore the ramifications of this finding for theories of lexical development. Finally, TRACE mimics the impact of phonological neighbourhoods on early word learning reported by Swingley and Aslin (2007). TRACE offers an alternative explanation of these findings in terms of mispronunciations of lexical items rather than imputing word learning to infants. Together these simulations provide an evaluation of Developmental (Jusczyk, 1993) and Familiarity (Metsala, 1999) accounts of word recognition by infants and young children. The findings point to a role for both theoretical approaches whereby vocabulary structure and content constrain infant word recognition in an experience-dependent fashion, and highlight the continuity in the processes and representations involved in lexical development during the second year of life. PMID:24493907

  16. An ERP investigation of visual word recognition in syllabary scripts.

    PubMed

    Okano, Kana; Grainger, Jonathan; Holcomb, Phillip J

    2013-06-01

    The bimodal interactive-activation model has been successfully applied to understanding the neurocognitive processes involved in reading words in alphabetic scripts, as reflected in the modulation of ERP components in masked repetition priming. In order to test the generalizability of this approach, in the present study we examined word recognition in a different writing system, the Japanese syllabary scripts hiragana and katakana. Native Japanese participants were presented with repeated or unrelated pairs of Japanese words in which the prime and target words were both in the same script (within-script priming, Exp. 1) or were in the opposite script (cross-script priming, Exp. 2). As in previous studies with alphabetic scripts, in both experiments the N250 (sublexical processing) and N400 (lexical-semantic processing) components were modulated by priming, although the time course was somewhat delayed. The earlier N/P150 effect (visual feature processing) was present only in "Experiment 1: Within-script priming", in which the prime and target words shared visual features. Overall, the results provide support for the hypothesis that visual word recognition involves a generalizable set of neurocognitive processes that operate in similar manners across different writing systems and languages, as well as pointing to the viability of the bimodal interactive-activation framework for modeling such processes.

  17. Vowel categorization during word recognition in bilingual toddlers.

    PubMed

    Ramon-Casas, Marta; Swingley, Daniel; Sebastián-Gallés, Núria; Bosch, Laura

    2009-08-01

    Toddlers' and preschoolers' knowledge of the phonological forms of words was tested in Spanish-learning, Catalan-learning, and bilingual children. These populations are of particular interest because of differences in the Spanish and Catalan vowel systems: Catalan has two vowels in a phonetic region where Spanish has only one. The proximity of the Spanish vowel to the Catalan ones might pose special learning problems. Children were shown picture pairs; the target picture's name was spoken correctly, or a vowel in the target word was altered. Altered vowels either contrasted with the usual vowel in Spanish and Catalan, or only in Catalan. Children's looking to the target picture was used as a measure of word recognition. Monolinguals' word recognition was hindered by within-language, but not non-native, vowel changes. Surprisingly, bilingual toddlers did not show sensitivity to changes in vowels contrastive only in Catalan. Among preschoolers, Catalan-dominant bilinguals but not Spanish-dominant bilinguals revealed mispronunciation sensitivity for the Catalan-only contrast. These studies reveal monolingual children's robust knowledge of native-language vowel categories in words, and show that bilingual children whose two languages contain phonetically overlapping vowel categories may not treat those categories as separate in language comprehension. PMID:19338984

  18. Vowel Categorization during Word Recognition in Bilingual Toddlers

    PubMed Central

    Ramon-Casas, Marta; Swingley, Daniel; Sebastián-Gallés, Núria; Bosch, Laura

    2009-01-01

    Toddlers’ and preschoolers’ knowledge of the phonological forms of words was tested in Spanish-learning, Catalan-learning, and bilingual children. These populations are of particular interest because of differences in the Spanish and Catalan vowel systems: Catalan has two vowels in a phonetic region where Spanish has only one. The proximity of the Spanish vowel to the Catalan ones might pose special learning problems. Children were shown picture pairs; the target picture’s name was spoken correctly, or a vowel in the target word was altered. Altered vowels either contrasted with the usual vowel in Spanish and Catalan, or only in Catalan. Children’s looking to the target picture was used as a measure of word recognition. Monolinguals’ word recognition was hindered by within-language, but not non-native, vowel changes. Surprisingly, bilingual toddlers did not show sensitivity to changes in vowels contrastive only in Catalan. Among preschoolers, Catalan-dominant bilinguals but not Spanish-dominant bilinguals revealed mispronunciation sensitivity for the Catalan-only contrast. These studies reveal monolingual children’s robust knowledge of native-language vowel categories in words, and show that bilingual children whose two languages contain phonetically overlapping vowel categories may not treat those categories as separate in language comprehension. PMID:19338984

  19. A multistream model of visual word recognition.

    PubMed

    Allen, Philip A; Smith, Albert F; Lien, Mei-Ching; Kaut, Kevin P; Canfield, Angie

    2009-02-01

    Four experiments are reported that test a multistream model of visual word recognition, which associates letter-level and word-level processing channels with three known visual processing streams isolated in macaque monkeys: the magno-dominated (MD) stream, the interblob-dominated (ID) stream, and the blob-dominated (BD) stream (Van Essen & Anderson, 1995). We show that mixing the color of adjacent letters of words does not result in facilitation of response times or error rates when the spatial-frequency pattern of a whole word is familiar. However, facilitation does occur when the spatial-frequency pattern of a whole word is not familiar. This pattern of results is not due to different luminance levels across the different-colored stimuli and the background because isoluminant displays were used. Also, the mixed-case, mixed-hue facilitation occurred when different display distances were used (Experiments 2 and 3), so this suggests that image normalization can adjust independently of object size differences. Finally, we show that this effect persists in both spaced and unspaced conditions (Experiment 4)--suggesting that inappropriate letter grouping by hue cannot account for these results. These data support a model of visual word recognition in which lower spatial frequencies are processed first in the more rapid MD stream. The slower ID and BD streams may process some lower spatial frequency information in addition to processing higher spatial frequency information, but these channels tend to lose the processing race to recognition unless the letter string is unfamiliar to the MD stream--as with mixed-case presentation.

  20. Visual word recognition during reading is followed by subvocal articulation.

    PubMed

    Eiter, Brianna M; Inhoff, Albrecht W

    2010-03-01

    Three experiments examined whether the identification of a visual word is followed by its subvocal articulation during reading. An irrelevant spoken word (ISW) that was identical, phonologically similar, or dissimilar to a visual target word was presented when the eyes moved to the target in the course of sentence reading. Sentence reading was further accompanied by either a sequential finger tapping task (Experiment 1) or an articulatory suppression task (Experiment 2). Experiment 1 revealed sound-specific interference from a phonologically similar ISW during posttarget viewing. This interference was absent in Experiment 2, where similar and dissimilar ISWs impeded target and posttarget reading equally. Experiment 3 showed that articulatory suppression left the lexical processing of visual words intact and that it did not diminish the influence of visual word recognition on eye guidance. The presence of sound-specific interference during posttarget reading in Experiment 1 is attributed to deleterious effects of a phonologically similar ISW on the subvocal articulation of a target. Its absence in Experiment 2 is attributed to the suppression of a target's subvocal articulation. PMID:20192542

  1. Is Early Word-form Processing Stress-full? How Natural Variability Supports Recognition

    PubMed Central

    Bortfeld, Heather; Morgan, James L.

    2010-01-01

    In a series of studies, we examined how mothers naturally stress words across multiple mentions in speech to their infants and how this marking influences infants’ recognition of words in fluent speech. We first collected samples of mothers’ infant-directed speech using a technique that induced multiple repetitions of target words. Acoustic analyses revealed that mothers systematically alternated between emphatic and nonemphatic stress when talking to their infants. Using the headturn preference procedure, we then tested 7.5-month-old infants on their ability to detect familiarized bisyllabic words in fluent speech. Stress of target words (emphatic and nonemphatic) was systematically varied across familiarization and recognition phases of four experiments. Results indicated that, although infants generally prefer listening to words produced with emphatic stress, recognition was enhanced when the degree of emphatic stress at familiarization matched the degree of emphatic stress at recognition. PMID:20159653

  2. Spoken word recognition without a TRACE

    PubMed Central

    Hannagan, Thomas; Magnuson, James S.; Grainger, Jonathan

    2013-01-01

    How do we map the rapid input of spoken language onto phonological and lexical representations over time? Attempts at psychologically-tractable computational models of spoken word recognition tend either to ignore time or to transform the temporal input into a spatial representation. TRACE, a connectionist model with broad and deep coverage of speech perception and spoken word recognition phenomena, takes the latter approach, using exclusively time-specific units at every level of representation. TRACE reduplicates featural, phonemic, and lexical inputs at every time step in a large memory trace, with rich interconnections (excitatory forward and backward connections between levels and inhibitory links within levels). As the length of the memory trace is increased, or as the phoneme and lexical inventory of the model is increased to a realistic size, this reduplication of time- (temporal position) specific units leads to a dramatic proliferation of units and connections, begging the question of whether a more efficient approach is possible. Our starting point is the observation that models of visual object recognition—including visual word recognition—have grappled with the problem of spatial invariance, and arrived at solutions other than a fully-reduplicative strategy like that of TRACE. This inspires a new model of spoken word recognition that combines time-specific phoneme representations similar to those in TRACE with higher-level representations based on string kernels: temporally independent (time invariant) diphone and lexical units. This reduces the number of necessary units and connections by several orders of magnitude relative to TRACE. Critically, we compare the new model to TRACE on a set of key phenomena, demonstrating that the new model inherits much of the behavior of TRACE and that the drastic computational savings do not come at the cost of explanatory power. PMID:24058349

  3. Comparison of Word Recognition Strategies of Children and Adults.

    ERIC Educational Resources Information Center

    Samuels, S. Jay; Chen, C. C.

    A word recognition model involving four processing stages was used, and tests of various word recognition strategies were administered to 25 fourth graders and 25 college students. The model included the following stages: (1) using information in a passage; (2) generating hypotheses from what the next word might be; (3) testing these hypotheses…

  4. Recognition of Spoken Words: Semantic Effects in Lexical Access

    ERIC Educational Resources Information Center

    Wurm, Lee H.; Vakoch, Douglas A.; Seaman, Sean R.

    2004-01-01

    Until recently most models of word recognition have assumed that semantic effects come into play only after the identification of the word in question. What little evidence exists for early semantic effects in word recognition has relied primarily on priming manipulations using the lexical decision task, and has used visual stimulus presentation.…

  5. Three Languages, One ECHO: Cognate Effects in Trilingual Word Recognition

    ERIC Educational Resources Information Center

    Lemhofer, Kristin; Dijkstra, Ton; Michel, Marije C.

    2004-01-01

    Research on bilingual word recognition suggests that lexical access is non-selective with respect to language, i.e., that word representations of both languages become active during recognition. One piece of evidence is that bilinguals recognise cognates (words that are identical or similar in form and meaning in two languages) faster than…

  6. The Temporal Dynamics of Spoken Word Recognition in Adverse Listening Conditions

    ERIC Educational Resources Information Center

    Brouwer, Susanne; Bradlow, Ann R.

    2016-01-01

    This study examined the temporal dynamics of spoken word recognition in noise and background speech. In two visual-world experiments, English participants listened to target words while looking at four pictures on the screen: a target (e.g. "candle"), an onset competitor (e.g. "candy"), a rhyme competitor (e.g.…

  7. Brain wave recognition of words

    PubMed Central

    Suppes, Patrick; Lu, Zhong-Lin; Han, Bing

    1997-01-01

    Electrical and magnetic brain waves of seven subjects under three experimental conditions were recorded for the purpose of recognizing which one of seven words was processed. The analysis consisted of averaging over trials to create prototypes and test samples, to both of which Fourier transforms were applied, followed by filtering and an inverse transformation to the time domain. The filters used were optimal predictive filters, selected for each subject and condition. Recognition rates, based on a least-squares criterion, varied widely, but all but one of 24 were significantly different from chance. The two best were above 90%. These results show that brain waves carry substantial information about the word being processed under experimental conditions of conscious awareness. PMID:9405722

  8. Emotion and language: Valence and arousal affect word recognition

    PubMed Central

    Brysbaert, Marc; Warriner, Amy Beth

    2014-01-01

    Emotion influences most aspects of cognition and behavior, but emotional factors are conspicuously absent from current models of word recognition. The influence of emotion on word recognition has mostly been reported in prior studies on the automatic vigilance for negative stimuli, but the precise nature of this relationship is unclear. Various models of automatic vigilance have claimed that the effect of valence on response times is categorical, an inverted-U, or interactive with arousal. The present study used a sample of 12,658 words, and included many lexical and semantic control factors, to determine the precise nature of the effects of arousal and valence on word recognition. Converging empirical patterns observed in word-level and trial-level data from lexical decision and naming indicate that valence and arousal exert independent monotonic effects: Negative words are recognized more slowly than positive words, and arousing words are recognized more slowly than calming words. Valence explained about 2% of the variance in word recognition latencies, whereas the effect of arousal was smaller. Valence and arousal do not interact, but both interact with word frequency, such that valence and arousal exert larger effects among low-frequency words than among high-frequency words. These results necessitate a new model of affective word processing whereby the degree of negativity monotonically and independently predicts the speed of responding. This research also demonstrates that incorporating emotional factors, especially valence, improves the performance of models of word recognition. PMID:24490848

  9. Word recognition performance in various background competitors.

    PubMed

    Sperry, J L; Wiley, T L; Chial, M R

    1997-04-01

    Word recognition performance was measured for 18 normal-hearing subjects using the female talker version of the Northwestern University Auditory Test No. 6 (NU-6) in the presence of three background competitors: (1) a meaningful multitalker competing message consisting of three male and three female talkers (forward multitalker competing message [FCM]), (2) the same multitalker competing message recorded in reverse to eliminate semantic content (backward multitalker competing message [BCM]), and (3) an amplitude-modulated speech-spectrum noise (SSN) having the same long-term average spectrum and amplitude fluctuations as the meaningful multitalker competing message. The meaningful competitor had a significantly more deleterious effect on recognition performance compared to performance for the two nonmeaningful competitors. Furthermore, the nonmeaningful speech competitor produced a significantly greater degradation in performance than that for the SSN.

  10. Coordination of Word Recognition and Oculomotor Control During Reading: The Role of Implicit Lexical Decisions

    PubMed Central

    Choi, Wonil; Gordon, Peter C.

    2013-01-01

    The coordination of word-recognition and oculomotor processes during reading was evaluated in two eye-tracking experiments that examined how word skipping, where a word is not fixated during first-pass reading, is affected by the lexical status of a letter string in the parafovea and ease of recognizing that string. Ease of lexical recognition was manipulated through target-word frequency (Experiment 1) and through repetition priming between prime-target pairs embedded in a sentence (Experiment 2). Using the gaze-contingent boundary technique the target word appeared in the parafovea either with full preview or with transposed-letter (TL) preview. The TL preview strings were nonwords in Experiment 1 (e.g., bilnk created from the target blink), but were words in Experiment 2 (e.g., sacred created from the target scared). Experiment 1 showed greater skipping for high-frequency than low-frequency target words in the full preview condition but not in the TL preview (nonword) condition. Experiment 2 showed greater skipping for target words that repeated an earlier prime word than for those that did not, with this repetition priming occurring both with preview of the full target and with preview of the target’s TL neighbor word. However, time to progress from the word after the target was greater following skips of the TL preview word, whose meaning was anomalous in the sentence context, than following skips of the full preview word whose meaning fit sensibly into the sentence context. Together, the results support the idea that coordination between word-recognition and oculomotor processes occurs at the level of implicit lexical decisions. PMID:23106372

  11. Influences of High and Low Variability on Infant Word Recognition

    ERIC Educational Resources Information Center

    Singh, Leher

    2008-01-01

    Although infants begin to encode and track novel words in fluent speech by 7.5 months, their ability to recognize words is somewhat limited at this stage. In particular, when the surface form of a word is altered, by changing the gender or affective prosody of the speaker, infants begin to falter at spoken word recognition. Given that natural…

  12. The Dynamics of Lexical Competition during Spoken Word Recognition

    ERIC Educational Resources Information Center

    Magnuson, James S.; Dixon, James A.; Tanenhaus, Michael K.; Aslin, Richard N.

    2007-01-01

    The sounds that make up spoken words are heard in a series and must be mapped rapidly onto words in memory because their elements, unlike those of visual words, cannot simultaneously exist or persist in time. Although theories agree that the dynamics of spoken word recognition are important, they differ in how they treat the nature of the…

  13. The Influence of the Phonological Neighborhood Clustering-Coefficient on Spoken Word Recognition

    PubMed Central

    Chan, Kit Ying; Vitevitch, Michael S.

    2009-01-01

    Clustering coefficient—a measure derived from the new science of networks—refers to the proportion of phonological neighbors of a target word that are also neighbors of each other. Consider the words bat, hat, and can, all of which are neighbors of the word cat; the words bat and hat are also neighbors of each other. In a perceptual identification task, words with a low clustering coefficient (i.e., few neighbors are neighbors of each other) were more accurately identified than words with a high clustering coefficient (i.e., many neighbors are neighbors of each other). In a lexical decision task, words with a low clustering coefficient were responded to more quickly than words with a high clustering coefficient. These findings suggest that the structure of the lexicon, that is the similarity relationships among neighbors of the target word measured by clustering coefficient, influences lexical access in spoken word recognition. Simulations of the TRACE and Shortlist models of spoken word recognition failed to account for the present findings. A framework for a new model of spoken word recognition is proposed. PMID:19968444

  14. Visual speech primes open-set recognition of spoken words

    PubMed Central

    Buchwald, Adam B.; Winters, Stephen J.; Pisoni, David B.

    2011-01-01

    Visual speech perception has become a topic of considerable interest to speech researchers. Previous research has demonstrated that perceivers neurally encode and use speech information from the visual modality, and this information has been found to facilitate spoken word recognition in tasks such as lexical decision (Kim, Davis, & Krins, 2004). In this paper, we used a cross-modality repetition priming paradigm with visual speech lexical primes and auditory lexical targets to explore the nature of this priming effect. First, we report that participants identified spoken words mixed with noise more accurately when the words were preceded by a visual speech prime of the same word compared with a control condition. Second, analyses of the responses indicated that both correct and incorrect responses were constrained by the visual speech information in the prime. These complementary results suggest that the visual speech primes have an effect on lexical access by increasing the likelihood that words with certain phonetic properties are selected. Third, we found that the cross-modality repetition priming effect was maintained even when visual and auditory signals came from different speakers, and thus different instances of the same lexical item. We discuss implications of these results for current theories of speech perception. PMID:21544260

  15. The Roles of Tonal and Segmental Information in Mandarin Spoken Word Recognition: An Eyetracking Study

    ERIC Educational Resources Information Center

    Malins, Jeffrey G.; Joanisse, Marc F.

    2010-01-01

    We used eyetracking to examine how tonal versus segmental information influence spoken word recognition in Mandarin Chinese. Participants heard an auditory word and were required to identify its corresponding picture from an array that included the target item ("chuang2" "bed"), a phonological competitor (segmental: chuang1 "window"; cohort:…

  16. The Role of Antibody in Korean Word Recognition

    ERIC Educational Resources Information Center

    Lee, Chang Hwan; Lee, Yoonhyoung; Kim, Kyungil

    2010-01-01

    A subsyllabic phonological unit, the antibody, has received little attention as a potential fundamental processing unit in word recognition. The psychological reality of the antibody in Korean recognition was investigated by looking at the performance of subjects presented with nonwords and words in the lexical decision task. In Experiment 1, the…

  17. Deaf Children's Recognition of Written Words: Is Fingerspelling the Basis?

    ERIC Educational Resources Information Center

    Mayberry, Rachel; Waters, Gloria S.

    To test three hypotheses concerning fingerspelling's contribution to word recognition, 24 deaf children in three age groups (7-9, 10-12, and 13-15 years) were administered a vocabulary recognition test and a lexical decision task. Subjects' performance was measured by the number of words accurately identified and the response latency. Results did…

  18. Orthographic Facilitation in Chinese Spoken Word Recognition: An ERP Study

    ERIC Educational Resources Information Center

    Zou, Lijuan; Desroches, Amy S.; Liu, Youyi; Xia, Zhichao; Shu, Hua

    2012-01-01

    Orthographic influences in spoken word recognition have been previously examined in alphabetic languages. However, it is unknown whether orthographic information affects spoken word recognition in Chinese, which has a clean dissociation between orthography (O) and phonology (P). The present study investigated orthographic effects using event…

  19. Function Words Constrain On-Line Recognition of Verbs and Nouns in French 18-Month-Olds

    ERIC Educational Resources Information Center

    Cauvet, Elodie; Limissuri, Rita; Millotte, Severine; Skoruppa, Katrin; Cabrol, Dominique; Christophe, Anne

    2014-01-01

    In this experiment using the conditioned head-turn procedure, 18-month-old French-learning toddlers were trained to respond to either a target noun ("la balle"/"the ball") or a target verb ("je mange"/"I ea"t). They were then tested on target word recognition in two syntactic contexts: the target word was…

  20. Phonotactics Constraints and the Spoken Word Recognition of Chinese Words in Speech

    ERIC Educational Resources Information Center

    Yip, Michael C.

    2016-01-01

    Two word-spotting experiments were conducted to examine the question of whether native Cantonese listeners are constrained by phonotactics information in spoken word recognition of Chinese words in speech. Because no legal consonant clusters occurred within an individual Chinese word, this kind of categorical phonotactics information of Chinese…

  1. Morphological Structures in Visual Word Recognition: The Case of Arabic

    ERIC Educational Resources Information Center

    Abu-Rabia, Salim; Awwad, Jasmin (Shalhoub)

    2004-01-01

    This research examined the function within lexical access of the main morphemic units from which most Arabic words are assembled, namely roots and word patterns. The present study focused on the derivation of nouns, in particular, whether the lexical representation of Arabic words reflects their morphological structure and whether recognition of a…

  2. A Distributed, Developmental Model of Word Recognition and Naming.

    ERIC Educational Resources Information Center

    Seidenberg, Mark S.; McClelland, James L.

    1989-01-01

    A parallel distributed processing model of visual word recognition and pronunciation is described. A key feature is the assumption that there is a simple, uniform procedure for computing a phonological representation from an orthographic representation for irregular words as well as regular words. (SLD)

  3. Morphological Influences on the Recognition of Monosyllabic Monomorphemic Words

    ERIC Educational Resources Information Center

    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…

  4. From Numbers to Letters: Feedback Regularization in Visual Word Recognition

    ERIC Educational Resources Information Center

    Molinaro, Nicola; Dunabeitia, Jon Andoni; Marin-Gutierrez, Alejandro; Carreiras, Manuel

    2010-01-01

    Word reading in alphabetic languages involves letter identification, independently of the format in which these letters are written. This process of letter "regularization" is sensitive to word context, leading to the recognition of a word even when numbers that resemble letters are inserted among other real letters (e.g., M4TERI4L). The present…

  5. Modelling the Effects of Semantic Ambiguity in Word Recognition

    ERIC Educational Resources Information Center

    Rodd, Jennifer M.; Gaskell, M. Gareth; Marslen-Wilson, William D.

    2004-01-01

    Most words in English are ambiguous between different interpretations; words can mean different things in different contexts. We investigate the implications of different types of semantic ambiguity for connectionist models of word recognition. We present a model in which there is competition to activate distributed semantic representations. The…

  6. Evidence for Early Morphological Decomposition in Visual Word Recognition

    ERIC Educational Resources Information Center

    Solomyak, Olla; Marantz, Alec

    2010-01-01

    We employ a single-trial correlational MEG analysis technique to investigate early processing in the visual recognition of morphologically complex words. Three classes of affixed words were presented in a lexical decision task: free stems (e.g., taxable), bound roots (e.g., tolerable), and unique root words (e.g., vulnerable, the root of which…

  7. See Before You Jump: Full Recognition of Parafoveal Words Precedes Skips During Reading

    PubMed Central

    Gordon, Peter C.; Plummer, Patrick; Choi, Wonil

    2013-01-01

    Serial attention models of eye-movement control during reading were evaluated in an eye-tracking experiment that examined how lexical activation combines with visual information in the parafovea to affect word skipping (where a word is not fixated during first-pass reading). Lexical activation was manipulated by repetition priming created through prime-target pairs embedded within a sentence. The boundary technique (Rayner, 1975) was used to determine whether the target word was fully available during parafoveal preview or whether it was available with transposed letters (e.g., Herman changed to Hreman). With full parafoveal preview, the target word was skipped more frequently when it matched the earlier prime word (i.e., was repeated) than when it did not match the earlier prime word (i.e., was new). With transposed-letter (TL) preview, repetition had no effect on skipping rates despite the great similarity of the TL preview string to the target word and substantial evidence that TL strings activate the words from which they are derived (Perea & Lupker, 2003). These results show that lexically-based skipping is based on full recognition of the letter string in parafoveal preview and does not involve using the contextual constraint to compensate for the reduced information available from the parafovea. These results are consistent with models of eye-movement control during reading in which successive words in a text are processed one at a time (serially) and in which word recognition strongly influences eye movements. PMID:22686842

  8. Foreign language learning, hyperlexia, and early word recognition.

    PubMed

    Sparks, R L; Artzer, M

    2000-01-01

    Children with hyperlexia read words spontaneously before the age of five, have impaired comprehension on both listening and reading tasks, and have word recognition skill above expectations based on cognitive and linguistic abilities. One student with hyperlexia and another student with higher word recognition than comprehension skills who started to read words at a very early age were followed over several years from the primary grades through high school when both were completing a second-year Spanish course. The purpose of the present study was to examine the foreign language (FL) word recognition, spelling, reading comprehension, writing, speaking, and listening skills of the two students and another high school student without hyperlexia. Results showed that the student without hyperlexia achieved higher scores than the hyperlexic student and the student with above average word recognition skills on most FL proficiency measures. The student with hyperlexia and the student with above average word recognition skills achieved higher scores on the Spanish proficiency tasks that required the exclusive use of phonological (pronunciation) and phonological/orthographic (word recognition, spelling) skills than on Spanish proficiency tasks that required the use of listening comprehension and speaking and writing skills. The findings provide support for the notion that word recognition and spelling in a FL may be modular processes and exist independently of general cognitive and linguistic skills. Results also suggest that students may have stronger FL learning skills in one language component than in other components of language, and that there may be a weak relationship between FL word recognition and oral proficiency in the FL. PMID:20563785

  9. Foreign language learning, hyperlexia, and early word recognition.

    PubMed

    Sparks, R L; Artzer, M

    2000-01-01

    Children with hyperlexia read words spontaneously before the age of five, have impaired comprehension on both listening and reading tasks, and have word recognition skill above expectations based on cognitive and linguistic abilities. One student with hyperlexia and another student with higher word recognition than comprehension skills who started to read words at a very early age were followed over several years from the primary grades through high school when both were completing a second-year Spanish course. The purpose of the present study was to examine the foreign language (FL) word recognition, spelling, reading comprehension, writing, speaking, and listening skills of the two students and another high school student without hyperlexia. Results showed that the student without hyperlexia achieved higher scores than the hyperlexic student and the student with above average word recognition skills on most FL proficiency measures. The student with hyperlexia and the student with above average word recognition skills achieved higher scores on the Spanish proficiency tasks that required the exclusive use of phonological (pronunciation) and phonological/orthographic (word recognition, spelling) skills than on Spanish proficiency tasks that required the use of listening comprehension and speaking and writing skills. The findings provide support for the notion that word recognition and spelling in a FL may be modular processes and exist independently of general cognitive and linguistic skills. Results also suggest that students may have stronger FL learning skills in one language component than in other components of language, and that there may be a weak relationship between FL word recognition and oral proficiency in the FL.

  10. Effects of word frequency, contextual diversity, and semantic distinctiveness on spoken word recognition

    PubMed Central

    Johns, Brendan T.; Gruenenfelder, Thomas M.; Pisoni, David B.; Jones, Michael N.

    2012-01-01

    The relative abilities of word frequency, contextual diversity, and semantic distinctiveness to predict accuracy of spoken word recognition in noise were compared using two data sets. Word frequency is the number of times a word appears in a corpus of text. Contextual diversity is the number of different documents in which the word appears in that corpus. Semantic distinctiveness takes into account the number of different semantic contexts in which the word appears. Semantic distinctiveness and contextual diversity were both able to explain variance above and beyond that explained by word frequency, which by itself explained little unique variance. PMID:22894319

  11. Visual Word Recognition during Reading Is Followed by Subvocal Articulation

    ERIC Educational Resources Information Center

    Eiter, Brianna M.; Inhoff, Albrecht W.

    2010-01-01

    Three experiments examined whether the identification of a visual word is followed by its subvocal articulation during reading. An irrelevant spoken word (ISW) that was identical, phonologically similar, or dissimilar to a visual target word was presented when the eyes moved to the target in the course of sentence reading. Sentence reading was…

  12. The Temporal Dynamics of Spoken Word Recognition in Adverse Listening Conditions.

    PubMed

    Brouwer, Susanne; Bradlow, Ann R

    2016-10-01

    This study examined the temporal dynamics of spoken word recognition in noise and background speech. In two visual-world experiments, English participants listened to target words while looking at four pictures on the screen: a target (e.g. candle), an onset competitor (e.g. candy), a rhyme competitor (e.g. sandal), and an unrelated distractor (e.g. lemon). Target words were presented in quiet, mixed with broadband noise, or mixed with background speech. Results showed that lexical competition changes throughout the observation window as a function of what is presented in the background. These findings suggest that, rather than being strictly sequential, stream segregation and lexical competition interact during spoken word recognition. PMID:26420754

  13. Re-evaluating split-fovea processing in word recognition: effects of fixation location within words.

    PubMed

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

    2010-03-01

    It has been claimed that word recognition is affected fundamentally by the precise location at which a word is fixated because a precise split in hemispheric processing at the point of fixation causes all letters to the left and right of fixation to project to different, contralateral hemispheres. To assess this claim, 5-letter words (and nonwords) were presented for lexical decision when participants fixated the space immediately to the left (location 1) or right (location 6) of each stimulus, or one of the four possible inter-letter spaces (locations 2-5). Fixation location was controlled using an eye-tracker linked to a fixation-contingent display and all stimuli were presented entirely within foveal vision to avoid confounding influences of extrafoveal hemispheric projections. Performance was equally poorest when fixating locations 1 and 6 (when words were shown entirely to either the right and left of fixation), intermediate for location 5, and equally superior for locations 2, 3, and 4. Additional word-specific analyses also showed no evidence of the effects of fixation location on optimal word recognition predicted by split-fovea processing. These findings suggest that, while fixation location influences word recognition, word recognition is apparently not affected by a split in hemispheric processing at the point of fixation and does not depend critically on the precise location at which a word is fixated. Implications of these findings for the role of fixation location in word recognition are discussed.

  14. Reading Habits, Perceptual Learning, and Recognition of Printed Words

    ERIC Educational Resources Information Center

    Nazir, Tatjana A.; Ben-Boutayab, Nadia; Decoppet, Nathalie; Deutsch, Avital; Frost, Ram

    2004-01-01

    The present work aims at demonstrating that visual training associated with the act of reading modifies the way we perceive printed words. As reading does not train all parts of the retina in the same way but favors regions on the side in the direction of scanning, visual word recognition should be better at retinal locations that are frequently…

  15. The Influence of Phonotactic Probability on Word Recognition in Toddlers

    ERIC Educational Resources Information Center

    MacRoy-Higgins, Michelle; Shafer, Valerie L.; Schwartz, Richard G.; Marton, Klara

    2014-01-01

    This study examined the influence of phonotactic probability on word recognition in English-speaking toddlers. Typically developing toddlers completed a preferential looking paradigm using familiar words, which consisted of either high or low phonotactic probability sound sequences. The participants' looking behavior was recorded in response…

  16. Pronounceability and the Visual Recognition of Nonsense Words

    ERIC Educational Resources Information Center

    Rubenstein, Herbert; And Others

    1975-01-01

    Evidence supports the hypothesis that visual word recognition may involve recoding into phonemic form. Less pronounceable nonsense words are recognized as nonsense faster than those more pronounceable. Differences in pronounceability may produce their effects during sequencing of neural instructions of each phoneme. (CHK)

  17. L2 Gender Facilitation and Inhibition in Spoken Word Recognition

    ERIC Educational Resources Information Center

    Behney, Jennifer N.

    2011-01-01

    This dissertation investigates the role of grammatical gender facilitation and inhibition in second language (L2) learners' spoken word recognition. Native speakers of languages that have grammatical gender are sensitive to gender marking when hearing and recognizing a word. Gender facilitation refers to when a given noun that is preceded by an…

  18. Using Constant Time Delay to Teach Braille Word Recognition

    ERIC Educational Resources Information Center

    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…

  19. Studying the Development of Word Recognition Using a Pseudoword Task

    ERIC Educational Resources Information Center

    Sipala, Christine E.

    2009-01-01

    Fluent reading hinges on automatic word recognition, yet little research has investigated the acquisition process with repeated exposure to novel words. In this study, elementary students in grades three to six were asked to read two-syllable pseudowords five times each (in varied sequences) during two sessions (n = 49). The goal was to study…

  20. Influences of High and Low Variability on Infant Word Recognition

    PubMed Central

    Singh, Leher

    2008-01-01

    Although infants begin to encode and track novel words in fluent speech by 7.5 months, their ability to recognize words is somewhat limited at this stage. In particular, when the surface form of a word is altered, by changing the gender or affective prosody of the speaker, infants begin to falter at spoken word recognition. Given that natural speech is replete with variability, only some of which is determines the meaning of a word, it remains unclear how infants might ever overcome the effects of surface variability without appealing to meaning. In the current set of experiments, consequences of high and low variability are examined in preverbal infants. The source of variability, vocal affect, is a common property of infant-directed speech with which young learners have to contend. Across a series of four experiments, infants' abilities to recognize repeated encounters of words, as well as to reject similar-sounding words, are investigated in the context of high and low affective variation. Results point to positive consequences of affective variation, both in creating generalizable memory representations for words, but also in establishing phonologically precise memories for words. Conversely, low variability appears to degrade word recognition on both fronts, compromising infants' abilities to generalize across different affective forms of a word and to detect similar-sounding items. Findings are discussed in the context of principles of categorization, both of a linguistic and non-linguistic variety, which may potentiate the early growth of a lexicon. PMID:17586482

  1. Form-based priming in spoken word recognition: the roles of competition and bias.

    PubMed

    Goldinger, S D; Luce, P A; Pisoni, D B; Marcario, J K

    1992-11-01

    Phonological priming of spoken words refers to improved recognition of targets preceded by primes that share at least one of their constituent phonemes (e.g., BULL-BEER). Phonetic priming refers to reduced recognition of targets preceded by primes that share no phonemes with targets but are phonetically similar to targets (e.g., BULL-VEER). Five experiments were conducted to investigate the role of bias in phonological priming. Performance was compared across conditions of phonological and phonetic priming under a variety of procedural manipulations. Ss in phonological priming conditions systematically modified their responses on unrelated priming trials in perceptual identification, and they were slower and more errorful on unrelated trials in lexical decision than were Ss in phonetic priming conditions. Phonetic and phonological priming effects display different time courses and also different interactions with changes in proportion of related priming trials. Phonological priming involves bias; phonetic priming appears to reflect basic properties of activation and competition in spoken word recognition.

  2. Phonetic discrimination and non-native spoken-word recognition

    NASA Astrophysics Data System (ADS)

    Weber, Andrea; Cutler, Anne

    2002-05-01

    When phoneme categories of a non-native language do not correspond to those of the native language, non-native categories may be inaccurately perceived. This may impair non-native spoken-word recognition. Weber and Cutler investigated the effect of phonetic discrimination difficulties on competitor activation in non-native listening. They tested whether Dutch listeners use English phonetic contrasts to resolve potential competition. Eye movements of Dutch participants were monitored as they followed spoken English instructions to click on pictures of objects. A target picture (e.g., picture of a paddle) was always presented along with distractor pictures. The name of a distractor picture either shared initial segments with the name of the target picture (e.g., target paddle, /paedl/ and competitor pedal, /pEdl/) or not (e.g., strawberry and duck). Half of the target-competitor pairs contained English vowels that are often confused by Dutch listeners (e.g., /ae/ and /E/ as in ``paddle-pedal''), half contained vowels that are unlikely to be confused (e.g., /ae/ and /aI/ as in ``parrot-pirate''). Dutch listeners fixated distractor pictures with confusable English vowels longer than distractor pictures with distinct vowels. The results demonstrate that the sensitivity of non-native listeners to phonetic contrasts can result in spurious competitors that should not be activated for native listeners.

  3. Rapid Word Recognition as a Measure of Word-Level Automaticity and Its Relation to Other Measures of Reading

    ERIC Educational Resources Information Center

    Frye, Elizabeth M.; Gosky, Ross

    2012-01-01

    The present study investigated the relationship between rapid recognition of individual words (Word Recognition Test) and two measures of contextual reading: (1) grade-level Passage Reading Test (IRI passage) and (2) performance on standardized STAR Reading Test. To establish if time of presentation on the word recognition test was a factor in…

  4. Task modulation of disyllabic spoken word recognition in Mandarin Chinese: a unimodal ERP study

    PubMed Central

    Huang, Xianjun; Yang, Jin-Chen; Chang, Ruohan; Guo, Chunyan

    2016-01-01

    Using unimodal auditory tasks of word-matching and meaning-matching, this study investigated how the phonological and semantic processes in Chinese disyllabic spoken word recognition are modulated by top-down mechanism induced by experimental tasks. Both semantic similarity and word-initial phonological similarity between the primes and targets were manipulated. Results showed that at early stage of recognition (~150–250 ms), an enhanced P2 was elicited by the word-initial phonological mismatch in both tasks. In ~300–500 ms, a fronto-central negative component was elicited by word-initial phonological similarities in the word-matching task, while a parietal negativity was elicited by semantically unrelated primes in the meaning-matching task, indicating that both the semantic and phonological processes can be involved in this time window, depending on the task requirements. In the late stage (~500–700 ms), a centro-parietal Late N400 was elicited in both tasks, but with a larger effect in the meaning-matching task than in the word-matching task. This finding suggests that the semantic representation of the spoken words can be activated automatically in the late stage of recognition, even when semantic processing is not required. However, the magnitude of the semantic activation is modulated by task requirements. PMID:27180951

  5. Letter visibility and word recognition: the optimal viewing position in printed words.

    PubMed

    Nazir, T A; Heller, D; Sussmann, C

    1992-09-01

    It has repeatedly been shown that the time and accuracy of recognizing a word depend strongly on where in the word the eye is fixating. Word-recognition performance is maximal when the eye fixates a region near the word's center, and decreases to both sides of this "optimal viewing position." The reason for this phenomenon is assumed to be the strong drop-off of visual acuity: the visibility of letters decreases with increasing eccentricity from fixation location. Consequently, fewer letters can be identified when the beginning or ending of a word is fixated than when its center is fixated. The present study is a test of this visual acuity hypothesis. If the phenomenon is caused by letter visibility, then it should be sensitive to variations of visual conditions in which the letters are presented. By increasing the interletter distances of the word (e.g., a_t_t_e_m_p_t), letter visibility was decreased. As expected from our hypothesis, the viewing-position effect became more exaggerated. An additional experiment showed that destroying word-shape information (e.g., aTtEmPt) decreased overall word-recognition performance but had no influence on the viewing-position effect. Varying the viewing position in words might thus be used as a paradigm, allowing one to separate out the contribution of letter information and supraletter information to word recognition.

  6. Semantic information mediates visual attention during spoken word recognition in Chinese: Evidence from the printed-word version of the visual-world paradigm.

    PubMed

    Shen, Wei; Qu, Qingqing; Li, Xingshan

    2016-07-01

    In the present study, we investigated whether the activation of semantic information during spoken word recognition can mediate visual attention's deployment to printed Chinese words. We used a visual-world paradigm with printed words, in which participants listened to a spoken target word embedded in a neutral spoken sentence while looking at a visual display of printed words. We examined whether a semantic competitor effect could be observed in the printed-word version of the visual-world paradigm. In Experiment 1, the relationship between the spoken target words and the printed words was manipulated so that they were semantically related (a semantic competitor), phonologically related (a phonological competitor), or unrelated (distractors). We found that the probability of fixations on semantic competitors was significantly higher than that of fixations on the distractors. In Experiment 2, the orthographic similarity between the spoken target words and their semantic competitors was manipulated to further examine whether the semantic competitor effect was modulated by orthographic similarity. We found significant semantic competitor effects regardless of orthographic similarity. Our study not only reveals that semantic information can affect visual attention, it also provides important new insights into the methodology employed to investigate the semantic processing of spoken words during spoken word recognition using the printed-word version of the visual-world paradigm. PMID:26993126

  7. Recognition of function words in 8-month-old French-learning infants

    NASA Astrophysics Data System (ADS)

    Shi, Rushen; Gauthier, Bruno

    2005-04-01

    Previous work has shown that German-learning 7-9-month-old infants recognize function words (Hoehle and Weissenborn, 2003). English-learning infants recognize function words around 10.5-11 months (Schafer et al. 1998; Shady, 1996; Shi et al., 2003, 2004), and the highly frequent determiner ``the'' at 8 months (Shi et al., 2004). The present study investigates French-learning infants' recognition of function words. As French is a syllable-timing language, the fuller syllabic status may allow infants to recognize function words earlier than English-learning infants. Syntactically and morphologically, functional elements occur more systematically in French than in English, providing reliable statistical cues to functor segmentation. Using a preferential looking procedure, we familiarized 8-month-olds with a target function word (``des,'' ``la,'' ``mes'' or ``ta''), and tested them with phrases containing the target versus a non-target. Results showed that infants' looking time to the phrases containing the targets versus those containing the non-targets differed significantly. Thus, infants recognized the target functors in continuous speech. As the targets included both high-frequency (``des,'' ``la'') and low-frequency (``mes,'' ``ta'') function words, we suggest that infants may begin segmenting high-frequency functors at an even younger age. The implications of early processing of function words to language acquisition will be discussed.

  8. Lexical and Metrical Stress in Word Recognition: Lexical or Pre-Lexical Influences?

    ERIC Educational Resources Information Center

    Slowiaczek, Louisa M.; Soltano, Emily G.; Bernstein, Hilary L.

    2006-01-01

    The influence of lexical stress and/or metrical stress on spoken word recognition was examined. Two experiments were designed to determine whether response times in lexical decision or shadowing tasks are influenced when primes and targets share lexical stress patterns (JUVenile-BIBlical [Syllables printed in capital letters indicate those…

  9. Orthographic Activation in L2 Spoken Word Recognition Depends on Proficiency: Evidence from Eye-Tracking.

    PubMed

    Veivo, Outi; Järvikivi, Juhani; Porretta, Vincent; Hyönä, Jukka

    2016-01-01

    The use of orthographic and phonological information in spoken word recognition was studied in a visual world task where L1 Finnish learners of L2 French (n = 64) and L1 French native speakers (n = 24) were asked to match spoken word forms with printed words while their eye movements were recorded. In Experiment 1, French target words were contrasted with competitors having a longer ( vs. ) or a shorter word initial phonological overlap ( vs. ) and an identical orthographic overlap. In Experiment 2, target words were contrasted with competitors of either longer ( vs. ) or shorter word initial orthographic overlap ( vs. ) and of an identical phonological overlap. A general phonological effect was observed in the L2 listener group but not in the L1 control group. No general orthographic effects were observed in the L2 or L1 groups, but a significant effect of proficiency was observed for orthographic overlap over time: higher proficiency L2 listeners used also orthographic information in the matching task in a time-window from 400 to 700 ms, whereas no such effect was observed for lower proficiency listeners. These results suggest that the activation of orthographic information in L2 spoken word recognition depends on proficiency in L2. PMID:27512381

  10. Orthographic Activation in L2 Spoken Word Recognition Depends on Proficiency: Evidence from Eye-Tracking

    PubMed Central

    Veivo, Outi; Järvikivi, Juhani; Porretta, Vincent; Hyönä, Jukka

    2016-01-01

    The use of orthographic and phonological information in spoken word recognition was studied in a visual world task where L1 Finnish learners of L2 French (n = 64) and L1 French native speakers (n = 24) were asked to match spoken word forms with printed words while their eye movements were recorded. In Experiment 1, French target words were contrasted with competitors having a longer ( vs. ) or a shorter word initial phonological overlap ( vs. ) and an identical orthographic overlap. In Experiment 2, target words were contrasted with competitors of either longer ( vs. ) or shorter word initial orthographic overlap ( vs. ) and of an identical phonological overlap. A general phonological effect was observed in the L2 listener group but not in the L1 control group. No general orthographic effects were observed in the L2 or L1 groups, but a significant effect of proficiency was observed for orthographic overlap over time: higher proficiency L2 listeners used also orthographic information in the matching task in a time-window from 400 to 700 ms, whereas no such effect was observed for lower proficiency listeners. These results suggest that the activation of orthographic information in L2 spoken word recognition depends on proficiency in L2. PMID:27512381

  11. The Role of Derivative Suffix Productivity in the Visual Word Recognition of Complex Words

    ERIC Educational Resources Information Center

    Lázaro, Miguel; Sainz, Javier; Illera, Víctor

    2015-01-01

    In this article we present two lexical decision experiments that examine the role of base frequency and of derivative suffix productivity in visual recognition of Spanish words. In the first experiment we find that complex words with productive derivative suffixes result in lower response times than those with unproductive derivative suffixes.…

  12. Sight Word Recognition among Young Children At-Risk: Picture-Supported vs. Word-Only

    ERIC Educational Resources Information Center

    Meadan, Hedda; Stoner, Julia B.; Parette, Howard P.

    2008-01-01

    A quasi-experimental design was used to investigate the impact of Picture Communication Symbols (PCS) on sight word recognition by young children identified as "at risk" for academic and social-behavior difficulties. Ten pre-primer and 10 primer Dolch words were presented to 23 students in the intervention group and 8 students in the control group…

  13. Word Recognition Error Analysis: Comparing Isolated Word List and Oral Passage Reading

    ERIC Educational Resources Information Center

    Flynn, Lindsay J.; Hosp, John L.; Hosp, Michelle K.; Robbins, Kelly P.

    2011-01-01

    The purpose of this study was to determine the relation between word recognition errors made at a letter-sound pattern level on a word list and on a curriculum-based measurement oral reading fluency measure (CBM-ORF) for typical and struggling elementary readers. The participants were second, third, and fourth grade typical and struggling readers…

  14. An Activation-Verification Model for Letter and Word Recognition: The Word-Superiority Effect.

    ERIC Educational Resources Information Center

    Paap, Kenneth R.; And Others

    1982-01-01

    An encoding algorithm uses empirically determined confusion matrices to activate units in an alphabetum and a lexicon to predict performance of word, orthographically regular nonword, or irregular nonword recognition. Performance is enhanced when decisions are based on lexical information which constrains test letter identity. Word prediction…

  15. Language Membership Identification Precedes Semantic Access: Suppression during Bilingual Word Recognition.

    PubMed

    Hoversten, Liv J; Brothers, Trevor; Swaab, Tamara Y; Traxler, Matthew J

    2015-11-01

    Previous research suggests that bilingual comprehenders access lexical representations of words in both languages nonselectively. However, it is unclear whether global language suppression plays a role in guiding attention to target language representations during ongoing lexico-semantic processing. To help clarify this issue, this study examined the relative timing of language membership and meaning activation during visual word recognition. Spanish-English bilinguals performed simultaneous semantic and language membership classification tasks on single words during EEG recording. Go/no-go ERP latencies provided evidence that language membership information was accessed before semantic information. Furthermore, N400 frequency effects indicated that the depth of processing of words in the nontarget language was reduced compared to the target language. These results suggest that the bilingual brain can rapidly identify the language to which a word belongs and subsequently use this information to selectively modulate the degree of processing in each language accordingly.

  16. Voice tracking and spoken word recognition in the presence of other voices

    NASA Astrophysics Data System (ADS)

    Litong-Palima, Marisciel; Violanda, Renante; Saloma, Caesar

    2004-12-01

    We study the human hearing process by modeling the hair cell as a thresholded Hopf bifurcator and compare our calculations with experimental results involving human subjects in two different multi-source listening tasks of voice tracking and spoken-word recognition. In the model, we observed noise suppression by destructive interference between noise sources which weakens the effective noise strength acting on the hair cell. Different success rate characteristics were observed for the two tasks. Hair cell performance at low threshold levels agree well with results from voice-tracking experiments while those of word-recognition experiments are consistent with a linear model of the hearing process. The ability of humans to track a target voice is robust against cross-talk interference unlike word-recognition performance which deteriorates quickly with the number of uncorrelated noise sources in the environment which is a response behavior that is associated with linear systems.

  17. Neighborhood effects in visual word recognition: facilitatory or inhibitory?

    PubMed

    Snodgrass, J G; Mintzer, M

    1993-03-01

    In five experiments, in which subjects were to identify a target word as it was gradually clarified, we manipulated the target's frequency of occurrence in the language and its neighborhood size--the number of words that can be constructed from a target word by changing one letter, while preserving letter position. In Experiments 1-4, visual identification performance to screen-fragmented words was measured. In Experiments 1 and 2, we used the ascending method of limits, whereas Experiments 3 and 4 presented a fixed-level fragment. In Experiment 1, there was no relation between overall accuracy and neighborhood size for words between three and six letters in length. However, more errors of commission (guesses) were made for high-neighborhood words and more errors of omission (blanks) were made for low-neighborhood words. Letter errors within guesses occurred at serial positions having many neighbors, and these positions were also likely to contain consonants rather than vowels. In Experiment 2, a small facilitatory effect of neighborhood size on both high- and low-frequency words was found. In contrast, in Experiments 3 and 4, using the same set of words, inhibitory effects of neighborhood size, but only for low-frequency words, were found. Experiment 5, using a speeded identification task, showed results parallel to those of Experiments 3 and 4. We suggest that whether neighborhood effects are facilitatory or inhibitory depends on whether feedback allows subjects to disconfirm initial hypotheses that the target is a high-frequency neighbor.

  18. Sink positive: linguistic experience with th substitutions influences nonnative word recognition.

    PubMed

    Hanulíková, Adriana; Weber, Andrea

    2012-04-01

    We used eyetracking, perceptual discrimination, and production tasks to examine the influences of perceptual similarity and linguistic experience on word recognition in nonnative (L2) speech. Eye movements to printed words were tracked while German and Dutch learners of English heard words containing one of three pronunciation variants (/t/, /s/, or /f/) of the interdental fricative /θ/. Irrespective of whether the speaker was Dutch or German, looking preferences for target words with /θ/ matched the preferences for producing /s/ variants in German speakers and /t/ variants in Dutch speakers (as determined via the production task), while a control group of English participants showed no such preferences. The perceptually most similar and most confusable /f/ variant (as determined via the discrimination task) was never preferred as a match for /θ/. These results suggest that linguistic experience with L2 pronunciations facilitates recognition of variants in an L2, with effects of frequency outweighing effects of perceptual similarity.

  19. Tracking the emergence of the consonant bias in visual-word recognition: evidence with developing readers.

    PubMed

    Soares, Ana Paula; Perea, Manuel; Comesaña, Montserrat

    2014-01-01

    Recent research with skilled adult readers has consistently revealed an advantage of consonants over vowels in visual-word recognition (i.e., the so-called "consonant bias"). Nevertheless, little is known about how early in development the consonant bias emerges. This work aims to address this issue by studying the relative contribution of consonants and vowels at the early stages of visual-word recognition in developing readers (2(nd) and 4(th) Grade children) and skilled adult readers (college students) using a masked priming lexical decision task. Target words starting either with a consonant or a vowel were preceded by a briefly presented masked prime (50 ms) that could be the same as the target (e.g., pirata-PIRATA [pirate-PIRATE]), a consonant-preserving prime (e.g., pureto-PIRATA), a vowel-preserving prime (e.g., gicala-PIRATA), or an unrelated prime (e.g., bocelo -PIRATA). Results revealed significant priming effects for the identity and consonant-preserving conditions in adult readers and 4(th) Grade children, whereas 2(nd) graders only showed priming for the identity condition. In adult readers, the advantage of consonants was observed both for words starting with a consonant or a vowel, while in 4(th) graders this advantage was restricted to words with an initial consonant. Thus, the present findings suggest that a Consonant/Vowel skeleton should be included in future (developmental) models of visual-word recognition and reading.

  20. Tracking the Emergence of the Consonant Bias in Visual-Word Recognition: Evidence with Developing Readers

    PubMed Central

    Soares, Ana Paula; Perea, Manuel; Comesaña, Montserrat

    2014-01-01

    Recent research with skilled adult readers has consistently revealed an advantage of consonants over vowels in visual-word recognition (i.e., the so-called “consonant bias”). Nevertheless, little is known about how early in development the consonant bias emerges. This work aims to address this issue by studying the relative contribution of consonants and vowels at the early stages of visual-word recognition in developing readers (2nd and 4th Grade children) and skilled adult readers (college students) using a masked priming lexical decision task. Target words starting either with a consonant or a vowel were preceded by a briefly presented masked prime (50 ms) that could be the same as the target (e.g., pirata-PIRATA [pirate-PIRATE]), a consonant-preserving prime (e.g., pureto-PIRATA), a vowel-preserving prime (e.g., gicala-PIRATA), or an unrelated prime (e.g., bocelo -PIRATA). Results revealed significant priming effects for the identity and consonant-preserving conditions in adult readers and 4th Grade children, whereas 2nd graders only showed priming for the identity condition. In adult readers, the advantage of consonants was observed both for words starting with a consonant or a vowel, while in 4th graders this advantage was restricted to words with an initial consonant. Thus, the present findings suggest that a Consonant/Vowel skeleton should be included in future (developmental) models of visual-word recognition and reading. PMID:24523917

  1. Tracking the emergence of the consonant bias in visual-word recognition: evidence with developing readers.

    PubMed

    Soares, Ana Paula; Perea, Manuel; Comesaña, Montserrat

    2014-01-01

    Recent research with skilled adult readers has consistently revealed an advantage of consonants over vowels in visual-word recognition (i.e., the so-called "consonant bias"). Nevertheless, little is known about how early in development the consonant bias emerges. This work aims to address this issue by studying the relative contribution of consonants and vowels at the early stages of visual-word recognition in developing readers (2(nd) and 4(th) Grade children) and skilled adult readers (college students) using a masked priming lexical decision task. Target words starting either with a consonant or a vowel were preceded by a briefly presented masked prime (50 ms) that could be the same as the target (e.g., pirata-PIRATA [pirate-PIRATE]), a consonant-preserving prime (e.g., pureto-PIRATA), a vowel-preserving prime (e.g., gicala-PIRATA), or an unrelated prime (e.g., bocelo -PIRATA). Results revealed significant priming effects for the identity and consonant-preserving conditions in adult readers and 4(th) Grade children, whereas 2(nd) graders only showed priming for the identity condition. In adult readers, the advantage of consonants was observed both for words starting with a consonant or a vowel, while in 4(th) graders this advantage was restricted to words with an initial consonant. Thus, the present findings suggest that a Consonant/Vowel skeleton should be included in future (developmental) models of visual-word recognition and reading. PMID:24523917

  2. Dissociations between Serial Position and Number of Letters Effects in Lateralised Visual Word Recognition

    ERIC Educational Resources Information Center

    Lavidor, Michal; Bailey, Peter J.

    2005-01-01

    Some previous studies of visual word recognition have reported an interaction between visual field and word length (measured by number of letters), such that recognition is affected more by word length for words presented in the left than for words presented in the right visual field. However, when manipulating serial position of letters in words…

  3. Syllable Frequency and Spoken Word Recognition: An Inhibitory Effect.

    PubMed

    González-Alvarez, Julio; Palomar-García, María-Angeles

    2016-08-01

    Research has shown that syllables play a relevant role in lexical access in Spanish, a shallow language with a transparent syllabic structure. Syllable frequency has been shown to have an inhibitory effect on visual word recognition in Spanish. However, no study has examined the syllable frequency effect on spoken word recognition. The present study tested the effect of the frequency of the first syllable on recognition of spoken Spanish words. A sample of 45 young adults (33 women, 12 men; M = 20.4, SD = 2.8; college students) performed an auditory lexical decision on 128 Spanish disyllabic words and 128 disyllabic nonwords. Words were selected so that lexical and first syllable frequency were manipulated in a within-subject 2 × 2 design, and six additional independent variables were controlled: token positional frequency of the second syllable, number of phonemes, position of lexical stress, number of phonological neighbors, number of phonological neighbors that have higher frequencies than the word, and acoustical durations measured in milliseconds. Decision latencies and error rates were submitted to linear mixed models analysis. Results showed a typical facilitatory effect of the lexical frequency and, importantly, an inhibitory effect of the first syllable frequency on reaction times and error rates.

  4. Syllable Frequency and Spoken Word Recognition: An Inhibitory Effect.

    PubMed

    González-Alvarez, Julio; Palomar-García, María-Angeles

    2016-08-01

    Research has shown that syllables play a relevant role in lexical access in Spanish, a shallow language with a transparent syllabic structure. Syllable frequency has been shown to have an inhibitory effect on visual word recognition in Spanish. However, no study has examined the syllable frequency effect on spoken word recognition. The present study tested the effect of the frequency of the first syllable on recognition of spoken Spanish words. A sample of 45 young adults (33 women, 12 men; M = 20.4, SD = 2.8; college students) performed an auditory lexical decision on 128 Spanish disyllabic words and 128 disyllabic nonwords. Words were selected so that lexical and first syllable frequency were manipulated in a within-subject 2 × 2 design, and six additional independent variables were controlled: token positional frequency of the second syllable, number of phonemes, position of lexical stress, number of phonological neighbors, number of phonological neighbors that have higher frequencies than the word, and acoustical durations measured in milliseconds. Decision latencies and error rates were submitted to linear mixed models analysis. Results showed a typical facilitatory effect of the lexical frequency and, importantly, an inhibitory effect of the first syllable frequency on reaction times and error rates. PMID:27287267

  5. Effects of Hearing and Aging on Sentence-Level Time-Gated Word Recognition

    PubMed Central

    Molis, Michelle R.; Kampel, Sean D.; McMillan, Garnett P.; Gallun, Frederick J.; Dann, Serena M.; Konrad-Martin, Dawn

    2015-01-01

    Purpose Aging is known to influence temporal processing, but its relationship to speech perception has not been clearly defined. To examine listeners’ use of contextual and phonetic information, the Revised Speech Perception in Noise test (R-SPIN) was used to develop a time-gated word (TGW) task Method In Experiment 1, R-SPIN sentence lists were matched on context, target-word length, and median word segment length necessary for target recognition. In Experiment 2, TGW recognition was assessed in quiet and in noise among adults of various ages with normal hearing to moderate hearing loss. Linear regression models of the minimum word duration necessary for correct identification and identification failure rates were developed. Age and hearing thresholds were modeled as continuous predictors with corrections for correlations among multiple measurements of the same participants. Results While aging and hearing loss both had significant impacts on task performance in the most adverse listening condition (low context, in noise), for most conditions, performance was limited primarily by hearing loss. Conclusion Whereas hearing loss was strongly related to target-word recognition, the effect of aging was only weakly related to task performance. These results have implications for the design and evaluation of studies of hearing and aging. PMID:25815688

  6. The Word Shape Hypothesis Re-Examined: Evidence for an External Feature Advantage in Visual Word Recognition

    ERIC Educational Resources Information Center

    Beech, John R.; Mayall, Kate A.

    2005-01-01

    This study investigates the relative roles of internal and external letter features in word recognition. In Experiment 1 the efficacy of outer word fragments (words with all their horizontal internal features removed) was compared with inner word fragments (words with their outer features removed) as primes in a forward masking paradigm. These…

  7. Recognition of Hits in a Target

    NASA Astrophysics Data System (ADS)

    Semerak, Vojtech; Drahansky, Martin

    This paper describes two possible ways of hit recognition in a target. First method is based on frame differencing with use of a stabilization algorithm to eliminate movements of a target. Second method uses flood fill with random seed point definition to find hits in the target scene.

  8. Estimating verbal intelligence in unipolar depression: comparison of word definition and word recognition.

    PubMed

    Suslow, Thomas

    2009-01-01

    Depression is known to be associated with deficits in effortful processing and word fluency. Automatic processes, instead, appear largely intact in depressed patients. It was investigated whether active word definition could be a less appropriate method than passive word recognition as a measure of verbal intelligence in depression. The valid assessment of premorbid IQ is important for correct comparison with current cognitive efficiency of depressed individuals, since premorbid IQ serves as baseline or control parameter to estimate the extent and severity of acquired cognitive impairments, both in the clinical and the research context. Two vocabulary tests were administered to 90 patients (31 women) with unipolar depression and 30 control subjects (15 women): a word definition task [the vocabulary subtest of the Wechsler Adult Intelligence Scale (WAIS-R)] and a word recognition task [the Multiple choice vocabulary test (MWT)]. In the depressed sample, scores of the MWT tended to be higher than WAIS-R scores. For depressed women, the MWT score was significantly higher than the WAIS-R score. In the control sample, no differences between MWT and WAIS-R scores were observed. Our findings indicate that word definition tasks could underestimate verbal intelligence especially in depressed women. For depressed women, it could be more appropriate to administer word recognition than word definition as an estimate of premorbid or verbal intelligence.

  9. The Effects of Multiple Script Priming on Word Recognition by the Two Cerebral Hemispheres: Implications for Discourse Processing

    ERIC Educational Resources Information Center

    Faust, Miriam; Barak, Ofra; Chiarello, Christine

    2006-01-01

    The present study examined left (LH) and right (RH) hemisphere involvement in discourse processing by testing the ability of each hemisphere to use world knowledge in the form of script contexts for word recognition. Participants made lexical decisions to laterally presented target words preceded by centrally presented script primes (four…

  10. Context and Spoken Word Recognition in a Novel Lexicon

    ERIC Educational Resources Information Center

    Revill, Kathleen Pirog; Tanenhaus, Michael K.; Aslin, Richard N.

    2008-01-01

    Three eye movement studies with novel lexicons investigated the role of semantic context in spoken word recognition, contrasting 3 models: restrictive access, access-selection, and continuous integration. Actions directed at novel shapes caused changes in motion (e.g., looming, spinning) or state (e.g., color, texture). Across the experiments,…

  11. "Context and Spoken Word Recognition in a Novel Lexicon": Correction

    ERIC Educational Resources Information Center

    Revill, Kathleen Pirog; Tanenhaus, Michael K.; Aslin, Richard N.

    2009-01-01

    Reports an error in "Context and spoken word recognition in a novel lexicon" by Kathleen Pirog Revill, Michael K. Tanenhaus and Richard N. Aslin ("Journal of Experimental Psychology: Learning, Memory, and Cognition," 2008[Sep], Vol 34[5], 1207-1223). Figure 9 was inadvertently duplicated as Figure 10. Figure 9 in the original article was correct.…

  12. ERP Evidence of Hemispheric Independence in Visual Word Recognition

    ERIC Educational Resources Information Center

    Nemrodov, Dan; Harpaz, Yuval; Javitt, Daniel C.; Lavidor, Michal

    2011-01-01

    This study examined the capability of the left hemisphere (LH) and the right hemisphere (RH) to perform a visual recognition task independently as formulated by the Direct Access Model (Fernandino, Iacoboni, & Zaidel, 2007). Healthy native Hebrew speakers were asked to categorize nouns and non-words (created from nouns by transposing two middle…

  13. Stimulus-based similarity and the recognition of spoken words

    NASA Astrophysics Data System (ADS)

    Auer, Edward T.

    2003-10-01

    Spoken word recognition has been hypothesized to be achieved via a competitive process amongst perceptually similar lexical candidates in the mental lexicon. In this process, lexical candidates are activated as a function of their perceived similarity to the spoken stimulus. The evidence supporting this hypothesis has largely come from studies of auditory word recognition. In this talk, evidence from our studies of visual spoken word recognition will be reviewed. Visual speech provides the opportunity to highlight the importance of stimulus-driven perceptual similarity because it presents a different pattern of segmental similarity than is afforded by auditory speech degraded by noise. Our results are consistent with stimulus-driven activation followed by competition as general spoken word recognition mechanism. In addition, results will be presented from recent investigations of the direct prediction of perceptual similarity from measurements of spoken stimuli. High levels of correlation have been observed between the predicted and perceptually obtained distances for a large set of spoken consonants. These results support the hypothesis that the perceptual structure of English consonants and vowels is predicted by stimulus structure without the need for an intervening level of abstract linguistic representation. [Research supported by NSF IIS 9996088 and NIH DC04856.

  14. Auditory and Visual Word Recognition in Beginning Adult Readers.

    ERIC Educational Resources Information Center

    Johnson, Raymond L.; Cortwright, Richard W.

    An exploratory investigation was made of cross-modality matching within the context of word recognition skills among beginning adult readers. The specific aim of the study was to assess the possibility that a deficit in cross-modality matching might be potentially useful as a diagnostic and predictive indicator of the rate at which adults learn to…

  15. Cross-Modal Source Information and Spoken Word Recognition

    ERIC Educational Resources Information Center

    Lachs, Lorin; Pisoni, David B.

    2004-01-01

    In a cross-modal matching task, participants were asked to match visual and auditory displays of speech based on the identity of the speaker. The present investigation used this task with acoustically transformed speech to examine the properties of sound that can convey cross-modal information. Word recognition performance was also measured under…

  16. Assessing the Development of Automaticity in Second Language Word Recognition.

    ERIC Educational Resources Information Center

    Segalowitz, Sidney J.; Segalowitz, Norman S.; Wood, Anthony G.

    1998-01-01

    In a study of development of automaticity in second-language word recognition, 105 English-speakers speaking French performed multiple lexical-decision tasks, and differences in coefficient of variation of lexical decision reaction time were compared cross- sectionally and longitudinally. Results confirm that with extended learning experience, the…

  17. The Influence of Semantic Neighbours on Visual Word Recognition

    ERIC Educational Resources Information Center

    Yates, Mark

    2012-01-01

    Although it is assumed that semantics is a critical component of visual word recognition, there is still much that we do not understand. One recent way of studying semantic processing has been in terms of semantic neighbourhood (SN) density, and this research has shown that semantic neighbours facilitate lexical decisions. However, it is not clear…

  18. Visual Speech Primes Open-Set Recognition of Spoken Words

    ERIC Educational Resources Information Center

    Buchwald, Adam B.; Winters, Stephen J.; Pisoni, David B.

    2009-01-01

    Visual speech perception has become a topic of considerable interest to speech researchers. Previous research has demonstrated that perceivers neurally encode and use speech information from the visual modality, and this information has been found to facilitate spoken word recognition in tasks such as lexical decision (Kim, Davis, & Krins, 2004).…

  19. Spoken Word Recognition in Toddlers Who Use Cochlear Implants

    ERIC Educational Resources Information Center

    Grieco-Calub, Tina M.; Saffran, Jenny R.; Litovsky, Ruth Y.

    2009-01-01

    Purpose: The purpose of this study was to assess the time course of spoken word recognition in 2-year-old children who use cochlear implants (CIs) in quiet and in the presence of speech competitors. Method: Children who use CIs and age-matched peers with normal acoustic hearing listened to familiar auditory labels, in quiet or in the presence of…

  20. Hemispheric Differences in Indexical Specificity Effects in Spoken Word Recognition

    ERIC Educational Resources Information Center

    Gonzalez, Julio; McLennan, Conor T.

    2007-01-01

    Variability in talker identity, one type of indexical variation, has demonstrable effects on the speed and accuracy of spoken word recognition. Furthermore, neuropsychological evidence suggests that indexical and linguistic information may be represented and processed differently in the 2 cerebral hemispheres, and is consistent with findings from…

  1. Automatization and Orthographic Development in Second Language Visual Word Recognition

    ERIC Educational Resources Information Center

    Kida, Shusaku

    2016-01-01

    The present study investigated second language (L2) learners' acquisition of automatic word recognition and the development of L2 orthographic representation in the mental lexicon. Participants in the study were Japanese university students enrolled in a compulsory course involving a weekly 30-minute sustained silent reading (SSR) activity with…

  2. Prosodic Phonological Representations Early in Visual Word Recognition

    ERIC Educational Resources Information Center

    Ashby, Jane; Martin, Andrea E.

    2008-01-01

    Two experiments examined the nature of the phonological representations used during visual word recognition. We tested whether a minimality constraint (R. Frost, 1998) limits the complexity of early representations to a simple string of phonemes. Alternatively, readers might activate elaborated representations that include prosodic syllable…

  3. Neural correlates of lexical access during visual word recognition.

    PubMed

    Binder, J R; McKiernan, K A; Parsons, M E; Westbury, C F; Possing, E T; Kaufman, J N; Buchanan, L

    2003-04-01

    People can discriminate real words from nonwords even when the latter are orthographically and phonologically word-like, presumably because words activate specific lexical and/or semantic information. We investigated the neural correlates of this identification process using event-related functional magnetic resonance imaging (fMRI). Participants performed a visual lexical decision task under conditions that encouraged specific word identification: Nonwords were matched to words on orthographic and phonologic characteristics, and accuracy was emphasized over speed. To identify neural responses associated with activation of nonsemantic lexical information, processing of words and nonwords with many lexical neighbors was contrasted with processing of items with no neighbors. The fMRI data showed robust differences in activation by words and word-like nonwords, with stronger word activation occurring in a distributed, left hemisphere network previously associated with semantic processing, and stronger nonword activation occurring in a posterior inferior frontal area previously associated with grapheme-to-phoneme mapping. Contrary to lexicon-based models of word recognition, there were no brain areas in which activation increased with neighborhood size. For words, activation in the left prefrontal, angular gyrus, and ventrolateral temporal areas was stronger for items without neighbors, probably because accurate responses to these items were more dependent on activation of semantic information. The results show neural correlates of access to specific word information. The absence of facilitatory lexical neighborhood effects on activation in these brain regions argues for an interpretation in terms of semantic access. Because subjects performed the same task throughout, the results are unlikely to be due to task-specific attentional, strategic, or expectancy effects.

  4. Are faces processed like words? A diagnostic test for recognition by parts.

    PubMed

    Martelli, Marialuisa; Majaj, Najib J; Pelli, Denis G

    2005-02-04

    Do we identify an object as a whole or by its parts? This simple question has been surprisingly hard to answer. It has been suggested that faces are recognized as wholes and words are recognized by parts. Here we answer the question by applying a test for crowding. In crowding, a target is harder to identify in the presence of nearby flankers. Previous work has described crowding between objects. We show that crowding also occurs between the parts of an object. Such internal crowding severely impairs perception, identification, and fMRI face-area activation. We apply a diagnostic test for crowding to a word and a face, and we find that the critical spacing of the parts required for recognition is proportional to distance from fixation and independent of size and kind. The critical spacing defines an isolation field around the target. Some objects can be recognized only when each part is isolated from the rest of the object by the critical spacing. In that case, recognition is by parts. Recognition is holistic if the observer can recognize the object even when the whole object fits within a critical spacing. Such an object has only one part. Multiple parts within an isolation field will crowd each other and spoil recognition. To assess the robustness of the crowding test, we manipulated familiarity through inversion and the face- and word-superiority effects. We find that threshold contrast for word and face identification is the product of two factors: familiarity and crowding. Familiarity increases sensitivity by a factor of x1.5, independent of eccentricity, while crowding attenuates sensitivity more and more as eccentricity increases. Our findings show that observers process words and faces in much the same way: The effects of familiarity and crowding do not distinguish between them. Words and faces are both recognized by parts, and their parts -- letters and facial features -- are recognized holistically. We propose that internal crowding be taken as the

  5. The frequency effect in second-language visual word recognition.

    PubMed

    Duyck, Wouter; Vanderelst, Dieter; Desmet, Timothy; Hartsuiker, Robert J

    2008-08-01

    A lexical decision experiment with Dutch-English bilinguals compared the effect of word frequency on visual word recognition in the first language with that in the second language. Bilinguals showed a considerably larger frequency effect in their second language, even though corpus frequency was matched across languages. Experiment 2 tested monolingual, native speakers of English on the English materials from Experiment 1. This yielded a frequency effect comparable to that of the bilinguals in Dutch (their L1). These results constrain the way in which existing models of word recognition can be extended to unbalanced bilingualism. In particular, the results are compatible with a theory by which the frequency effect originates from implicit learning. They are also compatible with models that attribute frequency effects to serial search in frequency-ordered bins (Murray & Forster, 2004), if these models are extended with the assumption that scanning speed is language dependent, or that bins are not language specific.

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

    PubMed Central

    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

  7. Changes in brain electrical activity during extended continuous word recognition.

    PubMed

    Van Strien, Jan W; Hagenbeek, Rogier E; Stam, Cornelis J; Rombouts, Serge A R B; Barkhof, Frederik

    2005-07-01

    Twenty healthy subjects (10 men, 10 women) participated in an EEG study with an extended continuous recognition memory task, in which each of 30 words was randomly shown 10 times and subjects were required to make old vs. new decisions. Both event-related brain potentials (ERPs) and induced band power (IBP) were investigated. We hypothesized that repeated presentations affect recollection rather than familiarity. For the 300- to 500-ms time window, an 'old/new' ERP effect was found for the first vs. second word presentations. The correct recognition of an 'old' word was associated with a more positive waveform than the correct identification of a new word. The old/new effect was most pronounced at and around the midline parietal electrode position. For the 500- to 800-ms time window, a linear repetition effect was found for multiple word repetitions. Correct recognition after an increasing number of repetitions was associated with increasing positivity. The multiple repetitions effect was most pronounced at the midline central (Cz) and fronto-central (FCz) electrode positions and reflects a graded recollection process: the stronger the memory trace grows, the more positive the ERP in the 500- to 800-ms time window. The ERP results support a dual-processing model, with familiarity being discernable from a more graded recollection state that depends on memory strengths. For IBP, we found 'old/new' effects for the lower-2 alpha, theta, and delta bands, with higher bandpower during 'old' words. The lower-2 alpha 'old/new' effect most probably reflects attentional processes, whereas the theta and delta effects reflect encoding and retrieval processes. Upon repeated word presentations, the magnitude of induced delta power in the 375- to 750-ms time window diminished linearly. Correlation analysis suggests that decreased delta power is moderately associated with faster decision speed and higher accuracy.

  8. Exploring the Neural Representation of Novel Words Learned through Enactment in a Word Recognition Task.

    PubMed

    Macedonia, Manuela; Mueller, Karsten

    2016-01-01

    Vocabulary learning in a second language is enhanced if learners enrich the learning experience with self-performed iconic gestures. This learning strategy is called enactment. Here we explore how enacted words are functionally represented in the brain and which brain regions contribute to enhance retention. After an enactment training lasting 4 days, participants performed a word recognition task in the functional Magnetic Resonance Imaging (fMRI) scanner. Data analysis suggests the participation of different and partially intertwined networks that are engaged in higher cognitive processes, i.e., enhanced attention and word recognition. Also, an experience-related network seems to map word representation. Besides core language regions, this latter network includes sensory and motor cortices, the basal ganglia, and the cerebellum. On the basis of its complexity and the involvement of the motor system, this sensorimotor network might explain superior retention for enactment. PMID:27445918

  9. Exploring the Neural Representation of Novel Words Learned through Enactment in a Word Recognition Task.

    PubMed

    Macedonia, Manuela; Mueller, Karsten

    2016-01-01

    Vocabulary learning in a second language is enhanced if learners enrich the learning experience with self-performed iconic gestures. This learning strategy is called enactment. Here we explore how enacted words are functionally represented in the brain and which brain regions contribute to enhance retention. After an enactment training lasting 4 days, participants performed a word recognition task in the functional Magnetic Resonance Imaging (fMRI) scanner. Data analysis suggests the participation of different and partially intertwined networks that are engaged in higher cognitive processes, i.e., enhanced attention and word recognition. Also, an experience-related network seems to map word representation. Besides core language regions, this latter network includes sensory and motor cortices, the basal ganglia, and the cerebellum. On the basis of its complexity and the involvement of the motor system, this sensorimotor network might explain superior retention for enactment.

  10. Exploring the Neural Representation of Novel Words Learned through Enactment in a Word Recognition Task

    PubMed Central

    Macedonia, Manuela; Mueller, Karsten

    2016-01-01

    Vocabulary learning in a second language is enhanced if learners enrich the learning experience with self-performed iconic gestures. This learning strategy is called enactment. Here we explore how enacted words are functionally represented in the brain and which brain regions contribute to enhance retention. After an enactment training lasting 4 days, participants performed a word recognition task in the functional Magnetic Resonance Imaging (fMRI) scanner. Data analysis suggests the participation of different and partially intertwined networks that are engaged in higher cognitive processes, i.e., enhanced attention and word recognition. Also, an experience-related network seems to map word representation. Besides core language regions, this latter network includes sensory and motor cortices, the basal ganglia, and the cerebellum. On the basis of its complexity and the involvement of the motor system, this sensorimotor network might explain superior retention for enactment. PMID:27445918

  11. Eye movements during spoken word recognition in Russian children.

    PubMed

    Sekerina, Irina A; Brooks, Patricia J

    2007-09-01

    This study explores incremental processing in spoken word recognition in Russian 5- and 6-year-olds and adults using free-viewing eye-tracking. Participants viewed scenes containing pictures of four familiar objects and clicked on a target embedded in a spoken instruction. In the cohort condition, two object names shared identical three-phoneme onsets. In the noncohort condition, all object names had unique onsets. Coarse-grain analyses of eye movements indicated that adults produced looks to the competitor on significantly more cohort trials than on noncohort trials, whereas children surprisingly failed to demonstrate cohort competition due to widespread exploratory eye movements across conditions. Fine-grain analyses, in contrast, showed a similar time course of eye movements across children and adults, but with cohort competition lingering more than 1s longer in children. The dissociation between coarse-grain and fine-grain eye movements indicates a need to consider multiple behavioral measures in making developmental comparisons in language processing. PMID:17560596

  12. Italians Use Abstract Knowledge about Lexical Stress during Spoken-Word Recognition

    ERIC Educational Resources Information Center

    Sulpizio, Simone; McQueen, James M.

    2012-01-01

    In two eye-tracking experiments in Italian, we investigated how acoustic information and stored knowledge about lexical stress are used during the recognition of tri-syllabic spoken words. Experiment 1 showed that Italians use acoustic cues to a word's stress pattern rapidly in word recognition, but only for words with antepenultimate stress.…

  13. A cascaded neuro-computational model for spoken word recognition

    NASA Astrophysics Data System (ADS)

    Hoya, Tetsuya; van Leeuwen, Cees

    2010-03-01

    In human speech recognition, words are analysed at both pre-lexical (i.e., sub-word) and lexical (word) levels. The aim of this paper is to propose a constructive neuro-computational model that incorporates both these levels as cascaded layers of pre-lexical and lexical units. The layered structure enables the system to handle the variability of real speech input. Within the model, receptive fields of the pre-lexical layer consist of radial basis functions; the lexical layer is composed of units that perform pattern matching between their internal template and a series of labels, corresponding to the winning receptive fields in the pre-lexical layer. The model adapts through self-tuning of all units, in combination with the formation of a connectivity structure through unsupervised (first layer) and supervised (higher layers) network growth. Simulation studies show that the model can achieve a level of performance in spoken word recognition similar to that of a benchmark approach using hidden Markov models, while enabling parallel access to word candidates in lexical decision making.

  14. Robotics control using isolated word recognition of voice input

    NASA Technical Reports Server (NTRS)

    Weiner, J. M.

    1977-01-01

    A speech input/output system is presented that can be used to communicate with a task oriented system. Human speech commands and synthesized voice output extend conventional information exchange capabilities between man and machine by utilizing audio input and output channels. The speech input facility is comprised of a hardware feature extractor and a microprocessor implemented isolated word or phrase recognition system. The recognizer offers a medium sized (100 commands), syntactically constrained vocabulary, and exhibits close to real time performance. The major portion of the recognition processing required is accomplished through software, minimizing the complexity of the hardware feature extractor.

  15. Lexical effects on spoken word recognition in children with normal hearing a

    PubMed Central

    Krull, Vidya; Choi, Sangsook; Kirk, Karen Iler; Prusick, Lindsay; French, Brian

    2009-01-01

    Summary This paper outlines the development of a theoretically-motivated sentence recognition test for children. Previous sentence tests such as the Lexical Neighborhood Test and the Multisyllabic Lexical Neighborhood Test examined lexical effects on children's recognition of words. In previous studies related to their test development, lexical characteristics were confounded. This study examines independent effects of word frequency and lexical density on a new test of spoken word recognition in children. Results show that word frequency and lexical density influence word recognition both independently, and in combination. Lexical density appears to be more heavily weighted than word frequency in children. PMID:19701087

  16. Working Memory Load Affects Processing Time in Spoken Word Recognition: Evidence from Eye-Movements.

    PubMed

    Hadar, Britt; Skrzypek, Joshua E; Wingfield, Arthur; Ben-David, Boaz M

    2016-01-01

    In daily life, speech perception is usually accompanied by other tasks that tap into working memory capacity. However, the role of working memory on speech processing is not clear. The goal of this study was to examine how working memory load affects the timeline for spoken word recognition in ideal listening conditions. We used the "visual world" eye-tracking paradigm. The task consisted of spoken instructions referring to one of four objects depicted on a computer monitor (e.g., "point at the candle"). Half of the trials presented a phonological competitor to the target word that either overlapped in the initial syllable (onset) or at the last syllable (offset). Eye movements captured listeners' ability to differentiate the target noun from its depicted phonological competitor (e.g., candy or sandal). We manipulated working memory load by using a digit pre-load task, where participants had to retain either one (low-load) or four (high-load) spoken digits for the duration of a spoken word recognition trial. The data show that the high-load condition delayed real-time target discrimination. Specifically, a four-digit load was sufficient to delay the point of discrimination between the spoken target word and its phonological competitor. Our results emphasize the important role working memory plays in speech perception, even when performed by young adults in ideal listening conditions. PMID:27242424

  17. Working Memory Load Affects Processing Time in Spoken Word Recognition: Evidence from Eye-Movements

    PubMed Central

    Hadar, Britt; Skrzypek, Joshua E.; Wingfield, Arthur; Ben-David, Boaz M.

    2016-01-01

    In daily life, speech perception is usually accompanied by other tasks that tap into working memory capacity. However, the role of working memory on speech processing is not clear. The goal of this study was to examine how working memory load affects the timeline for spoken word recognition in ideal listening conditions. We used the “visual world” eye-tracking paradigm. The task consisted of spoken instructions referring to one of four objects depicted on a computer monitor (e.g., “point at the candle”). Half of the trials presented a phonological competitor to the target word that either overlapped in the initial syllable (onset) or at the last syllable (offset). Eye movements captured listeners' ability to differentiate the target noun from its depicted phonological competitor (e.g., candy or sandal). We manipulated working memory load by using a digit pre-load task, where participants had to retain either one (low-load) or four (high-load) spoken digits for the duration of a spoken word recognition trial. The data show that the high-load condition delayed real-time target discrimination. Specifically, a four-digit load was sufficient to delay the point of discrimination between the spoken target word and its phonological competitor. Our results emphasize the important role working memory plays in speech perception, even when performed by young adults in ideal listening conditions. PMID:27242424

  18. Effects of word- and sentence-level contexts upon word recognition.

    PubMed

    Colombo, L; Williams, J

    1990-03-01

    In the present experiments, we investigated the facilitatory effects of auditorily presented prime words in neutral sentence contexts upon visually presented target words. It is shown that when the target task is a lexical decision, facilitation is obtained when the relationship between the prime and the target is one of synonymy (and low association strength). When instead the target is an antonym (again of low association strength), there is no priming effect; lexical decision is facilitated only when the prime word is presented in isolation. In further experiments, it is shown that primes in sentence contexts can produce facilitation of antonyms if they are strongly associated, or in the absence of association if the target must be named. The results are explained in terms of an integration process, which checks for the coherence between an upcoming word and the highest available level of representation of the context, but which affects only responses in the lexical decision task.

  19. (Almost) Word for Word: As Voice Recognition Programs Improve, Students Reap the Benefits

    ERIC Educational Resources Information Center

    Smith, Mark

    2006-01-01

    Voice recognition software is hardly new--attempts at capturing spoken words and turning them into written text have been available to consumers for about two decades. But what was once an expensive and highly unreliable tool has made great strides in recent years, perhaps most recognized in programs such as Nuance's Dragon NaturallySpeaking…

  20. A Demonstration of Improved Precision of Word Recognition Scores

    ERIC Educational Resources Information Center

    Schlauch, Robert S.; Anderson, Elizabeth S.; Micheyl, Christophe

    2014-01-01

    Purpose: The purpose of this study was to demonstrate improved precision of word recognition scores (WRSs) by increasing list length and analyzing phonemic errors. Method: Pure-tone thresholds (frequencies between 0.25 and 8.0 kHz) and WRSs were measured in 3 levels of speech-shaped noise (50, 52, and 54 dB HL) for 24 listeners with normal…

  1. Real-time functional architecture of visual word recognition.

    PubMed

    Whiting, Caroline; Shtyrov, Yury; Marslen-Wilson, William

    2015-02-01

    Despite a century of research into visual word recognition, basic questions remain unresolved about the functional architecture of the process that maps visual inputs from orthographic analysis onto lexical form and meaning and about the units of analysis in terms of which these processes are conducted. Here we use magnetoencephalography, supported by a masked priming behavioral study, to address these questions using contrasting sets of simple (walk), complex (swimmer), and pseudo-complex (corner) forms. Early analyses of orthographic structure, detectable in bilateral posterior temporal regions within a 150-230 msec time frame, are shown to segment the visual input into linguistic substrings (words and morphemes) that trigger lexical access in left middle temporal locations from 300 msec. These are primarily feedforward processes and are not initially constrained by lexical-level variables. Lexical constraints become significant from 390 msec, in both simple and complex words, with increased processing of pseudowords and pseudo-complex forms. These results, consistent with morpho-orthographic models based on masked priming data, map out the real-time functional architecture of visual word recognition, establishing basic feedforward processing relationships between orthographic form, morphological structure, and lexical meaning.

  2. Cross-linguistic experiments in word-form recognition

    NASA Astrophysics Data System (ADS)

    Vihman, Marilyn

    2001-05-01

    When do children first represent word forms without experimental training or contextual support? Both English- and Welsh-learning children were tested, replicating Halle and Boysson-Bardies (1994: French, 11 months.). Twelve children acquiring English showed word-form recognition by 11 months (Vihman et al., in press); 12 Welsh children showed the effect at 12 months but a separate sample of 12 tested at 11 months did not (Vihman and DePaolis, 1999). A subsequent study of 16 children using event-related potentials (ERPs) showed word-form recognition within 250 ms for English at 11 months (Thierry et al., 2003). Attempts to locate the age of onset longitudinally proved problematic: Repeated tests of single samples of English and Welsh monolingual children (12 each) at 9, 10, 11, and 12 months showed that infant episodic memory interferes sufficiently with longitudinal observation based on a single set of stimuli to preclude drawing any conclusions. Cross-sectional samples of monolingual English and Welsh children (24 each) are currently being tested at 9 to12 months, using both head turn and ERPs, as are English/Welsh bilingual children at 11 months. These studies should yield solid information as to the age of onset of spontaneous word form representation. [ESRC support is gratefully acknowledged.

  3. Extended target recognition in cognitive radar networks.

    PubMed

    Wei, Yimin; Meng, Huadong; Liu, Yimin; Wang, Xiqin

    2010-01-01

    We address the problem of adaptive waveform design for extended target recognition in cognitive radar networks. A closed-loop active target recognition radar system is extended to the case of a centralized cognitive radar network, in which a generalized likelihood ratio (GLR) based sequential hypothesis testing (SHT) framework is employed. Using Doppler velocities measured by multiple radars, the target aspect angle for each radar is calculated. The joint probability of each target hypothesis is then updated using observations from different radar line of sights (LOS). Based on these probabilities, a minimum correlation algorithm is proposed to adaptively design the transmit waveform for each radar in an amplitude fluctuation situation. Simulation results demonstrate performance improvements due to the cognitive radar network and adaptive waveform design. Our minimum correlation algorithm outperforms the eigen-waveform solution and other non-cognitive waveform design approaches.

  4. Electrophysiological correlates of morphological processing in Chinese compound word recognition

    PubMed Central

    Du, Yingchun; Hu, Weiping; Fang, Zhuo; Zhang, John X.

    2013-01-01

    The present study investigated the electrophysiological correlates of morphological processing in Chinese compound word reading using a delayed repetition priming paradigm. Participants were asked to passively view lists of two-character compound words containing prime-target pairs separated by a few items. In a Whole Word repetition condition, the prime and target were the same real words (e.g., , manager-manager). In a Constituent repetition condition, the prime and target were swapped in terms of their constituent position (e.g., , the former is a pseudo-word and the later means nurse). Two ERP components including N200 and N400 showed repetition effects. The N200 showed a negative shift upon repetition in the Whole Word condition but this effect was delayed for the Constituent condition. The N400 showed comparable amplitude reduction across the two priming conditions. The results reveal different aspects of morphological processing with an early stage associated with N200 and a late stage with N400. There was also a possibility that the N200 effect reflect general cognitive processing, i.e., the detection of low-probability stimuli. PMID:24068994

  5. Word learning: An ERP investigation of word experience effects on recognition and word processing

    PubMed Central

    Balass, Michal; Nelson, Jessica R.; Perfetti, Charles A.

    2012-01-01

    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 phonology); (2) orthography-to-phonology (no meaning); and (3) phonology-to-meaning (no orthography). Following learning, participants made meaning judgments on the learned words, familiar known words, and unpresented (unlearned) rare words while their ERPs were recorded. The behavioral results showed no significant effects of comprehension skill on meaning judgment performance. Contrastingly, the ERP results indicated comprehension skill differences in P600 amplitude; high-skilled readers showed stronger familiarity effects for learned words, whereas less-skilled readers did not distinguish between learned words, familiar words, and unlearned words. Evidence from the P600 and N400 illustrated superior learning of meaning when meaning information was coupled with orthography rather than phonology. These results suggest that the availability of word knowledge (orthography, phonology, and meaning) at learning affects subsequent word identification processes when the words are encountered in a new context. PMID:22399833

  6. Modeling Polymorphemic Word Recognition: Exploring Differences among Children with Early-Emerging and Late- Emerging Word Reading Difficulty

    ERIC Educational Resources Information Center

    Kearns, Devin M.; Steacy, Laura M.; Compton, Donald L.; Gilbert, Jennifer K.; Goodwin, Amanda P.; Cho, Eunsoo; Lindstrom, Esther R.; Collins, Alyson A.

    2016-01-01

    Comprehensive models of derived polymorphemic word recognition skill in developing readers, with an emphasis on children with reading difficulty (RD), have not been developed. The purpose of the present study was to model individual differences in polymorphemic word recognition ability at the item level among 5th-grade children (N = 173)…

  7. Laser range profiling for small target recognition

    NASA Astrophysics Data System (ADS)

    Steinvall, Ove; Tulldahl, Michael

    2016-05-01

    The detection and classification of small surface and airborne targets at long ranges is a growing need for naval security. Long range ID or ID at closer range of small targets has its limitations in imaging due to the demand on very high transverse sensor resolution. It is therefore motivated to look for 1D laser techniques for target ID. These include vibrometry, and laser range profiling. Vibrometry can give good results but is also sensitive to certain vibrating parts on the target being in the field of view. Laser range profiling is attractive because the maximum range can be substantial, especially for a small laser beam width. A range profiler can also be used in a scanning mode to detect targets within a certain sector. The same laser can also be used for active imaging when the target comes closer and is angular resolved. The present paper will show both experimental and simulated results for laser range profiling of small boats out to 6-7 km range and a UAV mockup at close range (1.3 km). We obtained good results with the profiling system both for target detection and recognition. Comparison of experimental and simulated range waveforms based on CAD models of the target support the idea of having a profiling system as a first recognition sensor and thus narrowing the search space for the automatic target recognition based on imaging at close ranges. The naval experiments took place in the Baltic Sea with many other active and passive EO sensors beside the profiling system. Discussion of data fusion between laser profiling and imaging systems will be given. The UAV experiments were made from the rooftop laboratory at FOI.

  8. The Bayesian Reader: Explaining Word Recognition as an Optimal Bayesian Decision Process

    ERIC Educational Resources Information Center

    Norris, Dennis

    2006-01-01

    This article presents a theory of visual word recognition that assumes that, in the tasks of word identification, lexical decision, and semantic categorization, human readers behave as optimal Bayesian decision makers. This leads to the development of a computational model of word recognition, the Bayesian reader. The Bayesian reader successfully…

  9. Asymmetries in Early Word Recognition: The Case of Stops and Fricatives

    ERIC Educational Resources Information Center

    Altvater-Mackensen, Nicole; van der Feest, Suzanne V. H.; Fikkert, Paula

    2014-01-01

    Toddlers' discrimination of native phonemic contrasts is generally unproblematic. Yet using those native contrasts in word learning and word recognition can be more challenging. In this article, we investigate perceptual versus phonological explanations for asymmetrical patterns found in early word recognition. We systematically investigated…

  10. Phonological and Visual Processes in Word Recognition by American Learners of Arabic as a Foreign Language.

    ERIC Educational Resources Information Center

    Khaldieh, Salim A.

    A study investigated the roles of phonological encoding and visual processes in word recognition in American learners of Arabic as a foreign language. Subjects were 36 individuals with proficiency ranging from beginning to native. Two experiments in word recognition were conducted, one at word and one at sentence level. At each level, the word…

  11. A Limited-Vocabulary, Multi-Speaker Automatic Isolated Word Recognition System.

    ERIC Educational Resources Information Center

    Paul, James E., Jr.

    Techniques for automatic recognition of isolated words are investigated, and a computer simulation of a word recognition system is effected. Considered in detail are data acquisition and digitizing, word detection, amplitude and time normalization, short-time spectral estimation including spectral windowing, spectral envelope approximation,…

  12. The Impact of Left and Right Intracranial Tumors on Picture and Word Recognition Memory

    ERIC Educational Resources Information Center

    Goldstein, Bram; Armstrong, Carol L.; Modestino, Edward; Ledakis, George; John, Cameron; Hunter, Jill V.

    2004-01-01

    This study investigated the effects of left and right intracranial tumors on picture and word recognition memory. We hypothesized that left hemispheric (LH) patients would exhibit greater word recognition memory impairment than right hemispheric (RH) patients, with no significant hemispheric group picture recognition memory differences. The LH…

  13. Tracking the Time Course of Word-Frequency Effects in Auditory Word Recognition with Event-Related Potentials

    ERIC Educational Resources Information Center

    Dufour, Sophie; Brunelliere, Angele; Frauenfelder, Ulrich H.

    2013-01-01

    Although the word-frequency effect is one of the most established findings in spoken-word recognition, the precise processing locus of this effect is still a topic of debate. In this study, we used event-related potentials (ERPs) to track the time course of the word-frequency effect. In addition, the neighborhood density effect, which is known to…

  14. Word recognition and phonetic structure acquisition: Possible relations

    NASA Astrophysics Data System (ADS)

    Morgan, James

    2002-05-01

    Several accounts of possible relations between the emergence of the mental lexicon and acquisition of native language phonological structure have been propounded. In one view, acquisition of word meanings guides infants' attention toward those contrasts that are linguistically significant in their language. In the opposing view, native language phonological categories may be acquired from statistical patterns of input speech, prior to and independent of learning at the lexical level. Here, a more interactive account will be presented, in which phonological structure is modeled as emerging consequentially from the self-organization of perceptual space underlying word recognition. A key prediction of this model is that early native language phonological categories will be highly context specific. Data bearing on this prediction will be presented which provide clues to the nature of infants' statistical analysis of input.

  15. Large-Corpus Phoneme and Word Recognition and the Generality of Lexical Context in CVC Word Perception

    ERIC Educational Resources Information Center

    Gelfand, Jessica T.; Christie, Robert E.; Gelfand, Stanley A.

    2014-01-01

    Purpose: Speech recognition may be analyzed in terms of recognition probabilities for perceptual wholes (e.g., words) and parts (e.g., phonemes), where j or the j-factor reveals the number of independent perceptual units required for recognition of the whole (Boothroyd, 1968b; Boothroyd & Nittrouer, 1988; Nittrouer & Boothroyd, 1990). For…

  16. Lexico-Semantic Structure and the Word-Frequency Effect in Recognition Memory

    ERIC Educational Resources Information Center

    Monaco, Joseph D.; Abbott, L. F.; Kahana, Michael J.

    2007-01-01

    The word-frequency effect (WFE) in recognition memory refers to the finding that more rare words are better recognized than more common words. We demonstrate that a familiarity-discrimination model operating on data from a semantic word-association space yields a robust WFE in data on both hit rates and false-alarm rates. Our modeling results…

  17. Extending models of visual-word recognition to semicursive scripts: Evidence from masked priming in Uyghur.

    PubMed

    Yakup, Mahire; Abliz, Wayit; Sereno, Joan; Perea, Manuel

    2015-12-01

    One basic feature of the Arabic script is its semicursive style: some letters are connected to the next, but others are not, as in the Uyghur word [see text]/ya xʃi/ ("good"). None of the current orthographic coding schemes in models of visual-word recognition, which were created for the Roman script, assign a differential role to the coding of within letter "chunks" and between letter "chunks" in words in the Arabic script. To examine how letter identity/position is coded at the earliest stages of word processing in the Arabic script, we conducted 2 masked priming lexical decision experiments in Uyghur, an agglutinative Turkic language. The target word was preceded by an identical prime, by a transposed-letter nonword prime (that either kept the ligation pattern or did not), or by a 2-letter replacement nonword prime. Transposed-letter primes were as effective as identity primes when the letter transposition in the prime kept the same ligation pattern as the target word (e.g., [see text]/inta_jin/-/itna_jin/), but not when the transposed-letter prime didn't keep the ligation pattern (e.g., [see text]/so_w_ʁa_t/-/so_ʁw_a_t/). Furthermore, replacement-letter primes were more effective when they kept the ligation pattern of the target word than when they did not (e.g., [see text]/so_d_ʧa_t/-/so_w_ʁa_t/ faster than [see text]/so_ʧd_a_t/-/so_w_ʁa_t/). We examined how input coding schemes could be extended to deal with the intricacies of semicursive scripts. PMID:26618626

  18. Onsets and codas in 1.5-year-olds’ word recognition

    PubMed Central

    Swingley, Daniel

    2009-01-01

    Previous tests of toddlers’ phonological knowledge of familiar words using word recognition tasks have examined syllable onsets but not word-final consonants (codas). However, there are good reasons to suppose that children’s knowledge of coda consonants might be less complete than their knowledge of onset consonants. To test this hypothesis, the present study examined 14- to 21-month-old children’s knowledge of the phonological forms of familiar words by measuring their comprehension of correctly-pronounced and mispronounced instances of those words using a visual fixation task. Mispronunciations substituted onset or coda consonants. Adults were tested in the same task for comparison with children. Children and adults fixated named targets more upon hearing correct pronunciations than upon hearing mispronunciations, whether those mispronunciations involved the word’s initial or final consonant. In addition, detailed analysis of the timing of adults’ and children’s eye movements provided clear evidence for incremental interpretation of the speech signal. Children’s responses were slower and less accurate overall, but children and adults showed nearly identical temporal effects of the placement of phonological substitutions. The results demonstrate accurate encoding of consonants even in words children cannot yet say. PMID:20126290

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

    PubMed Central

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

    2013-01-01

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

  20. The Influence of Orthographic Neighborhood Density and Word Frequency on Visual Word Recognition: Insights from RT Distributional Analyses

    PubMed Central

    Lim, Stephen Wee Hun

    2016-01-01

    The effects of orthographic neighborhood density and word frequency in visual word recognition were investigated using distributional analyses of response latencies in visual lexical decision. Main effects of density and frequency were observed in mean latencies. Distributional analyses additionally revealed a density × frequency interaction: for low-frequency words, density effects were mediated predominantly by distributional shifting whereas for high-frequency words, density effects were absent except at the slower RTs, implicating distributional skewing. The present findings suggest that density effects in low-frequency words reflect processes involved in early lexical access, while the effects observed in high-frequency words reflect late postlexical checking processes. PMID:27065902

  1. Improved word recognition for observers with age-related maculopathies using compensation filters

    NASA Technical Reports Server (NTRS)

    Lawton, Teri B.

    1988-01-01

    A method for improving word recognition for people with age-related maculopathies, which cause a loss of central vision, is discussed. It is found that the use of individualized compensation filters based on an person's normalized contrast sensitivity function can improve word recognition for people with age-related maculopathies. It is shown that 27-70 pct more magnification is needed for unfiltered words compared to filtered words. The improvement in word recognition is positively correlated with the severity of vision loss.

  2. Establishing a time-line of word recognition: evidence from eye movements and event-related potentials.

    PubMed

    Sereno, S C; Rayner, K; Posner, M I

    1998-07-13

    The average duration of eye fixations in reading places constraints on the time for lexical processing. Data from event related potential (ERP) studies of word recognition can illuminate stages of processing within a single fixation on a word. In the present study, high and low frequency regular and exception words were used as targets in an eye movement reading experiment and a high-density electrode ERP lexical decision experiment. Effects of lexicality (words vs pseudowords vs consonant strings), word frequency (high vs low frequency) and word regularity (regular vs exception spelling-sound correspondence) were examined. Results suggest a very early time-course for these aspects of lexical processing within the context of a single eye fixation. PMID:9694199

  3. Protein-targeted corona phase molecular recognition.

    PubMed

    Bisker, Gili; Dong, Juyao; Park, Hoyoung D; Iverson, Nicole M; Ahn, Jiyoung; Nelson, Justin T; Landry, Markita P; Kruss, Sebastian; Strano, Michael S

    2016-01-01

    Corona phase molecular recognition (CoPhMoRe) uses a heteropolymer adsorbed onto and templated by a nanoparticle surface to recognize a specific target analyte. This method has not yet been extended to macromolecular analytes, including proteins. Herein we develop a variant of a CoPhMoRe screening procedure of single-walled carbon nanotubes (SWCNT) and use it against a panel of human blood proteins, revealing a specific corona phase that recognizes fibrinogen with high selectivity. In response to fibrinogen binding, SWCNT fluorescence decreases by >80% at saturation. Sequential binding of the three fibrinogen nodules is suggested by selective fluorescence quenching by isolated sub-domains and validated by the quenching kinetics. The fibrinogen recognition also occurs in serum environment, at the clinically relevant fibrinogen concentrations in the human blood. These results open new avenues for synthetic, non-biological antibody analogues that recognize biological macromolecules, and hold great promise for medical and clinical applications. PMID:26742890

  4. Protein-targeted corona phase molecular recognition

    PubMed Central

    Bisker, Gili; Dong, Juyao; Park, Hoyoung D.; Iverson, Nicole M.; Ahn, Jiyoung; Nelson, Justin T.; Landry, Markita P.; Kruss, Sebastian; Strano, Michael S.

    2016-01-01

    Corona phase molecular recognition (CoPhMoRe) uses a heteropolymer adsorbed onto and templated by a nanoparticle surface to recognize a specific target analyte. This method has not yet been extended to macromolecular analytes, including proteins. Herein we develop a variant of a CoPhMoRe screening procedure of single-walled carbon nanotubes (SWCNT) and use it against a panel of human blood proteins, revealing a specific corona phase that recognizes fibrinogen with high selectivity. In response to fibrinogen binding, SWCNT fluorescence decreases by >80% at saturation. Sequential binding of the three fibrinogen nodules is suggested by selective fluorescence quenching by isolated sub-domains and validated by the quenching kinetics. The fibrinogen recognition also occurs in serum environment, at the clinically relevant fibrinogen concentrations in the human blood. These results open new avenues for synthetic, non-biological antibody analogues that recognize biological macromolecules, and hold great promise for medical and clinical applications. PMID:26742890

  5. Photonics: From target recognition to lesion detection

    NASA Technical Reports Server (NTRS)

    Henry, E. Michael

    1994-01-01

    Since 1989, Martin Marietta has invested in the development of an innovative concept for robust real-time pattern recognition for any two-dimensioanal sensor. This concept has been tested in simulation, and in laboratory and field hardware, for a number of DOD and commercial uses from automatic target recognition to manufacturing inspection. We have now joined Rose Health Care Systems in developing its use for medical diagnostics. The concept is based on determining regions of interest by using optical Fourier bandpassing as a scene segmentation technique, enhancing those regions using wavelet filters, passing the enhanced regions to a neural network for analysis and initial pattern identification, and following this initial identification with confirmation by optical correlation. The optical scene segmentation and pattern confirmation are performed by the same optical module. The neural network is a recursive error minimization network with a small number of connections and nodes that rapidly converges to a global minimum.

  6. Do Diacritical Marks Play a Role at the Early Stages of Word Recognition in Arabic?

    PubMed Central

    Perea, Manuel; Abu Mallouh, Reem; Mohammed, Ahmed; Khalifa, Batoul; Carreiras, Manuel

    2016-01-01

    A crucial question in the domain of visual word recognition is whether letter similarity plays a role in the early stages of visual word processing. Here we focused on Arabic because in this language there are various groups of letters that share the same basic shape and only differ in the number/location of diacritical points. We conducted a masked priming lexical decision experiment in which a target word was preceded by: (i) an identity prime; (ii) a prime in which the critical letter was replaced by a letter with the same shape that differed in the number of diacritics (e.g., ); or (iii) a prime in which the critical letter was replaced by a letter with different shape (e.g., ). Results showed a sizable advantage of the identity condition over the two substituted-letter priming conditions (i.e., diacritical information is rapidly processed). Thus, diacritical marks play an essential role in the “feature letter” level of models of visual word recognition in Arabic. PMID:27597838

  7. Do Diacritical Marks Play a Role at the Early Stages of Word Recognition in Arabic?

    PubMed Central

    Perea, Manuel; Abu Mallouh, Reem; Mohammed, Ahmed; Khalifa, Batoul; Carreiras, Manuel

    2016-01-01

    A crucial question in the domain of visual word recognition is whether letter similarity plays a role in the early stages of visual word processing. Here we focused on Arabic because in this language there are various groups of letters that share the same basic shape and only differ in the number/location of diacritical points. We conducted a masked priming lexical decision experiment in which a target word was preceded by: (i) an identity prime; (ii) a prime in which the critical letter was replaced by a letter with the same shape that differed in the number of diacritics (e.g., ); or (iii) a prime in which the critical letter was replaced by a letter with different shape (e.g., ). Results showed a sizable advantage of the identity condition over the two substituted-letter priming conditions (i.e., diacritical information is rapidly processed). Thus, diacritical marks play an essential role in the “feature letter” level of models of visual word recognition in Arabic.

  8. Do Diacritical Marks Play a Role at the Early Stages of Word Recognition in Arabic?

    PubMed

    Perea, Manuel; Abu Mallouh, Reem; Mohammed, Ahmed; Khalifa, Batoul; Carreiras, Manuel

    2016-01-01

    A crucial question in the domain of visual word recognition is whether letter similarity plays a role in the early stages of visual word processing. Here we focused on Arabic because in this language there are various groups of letters that share the same basic shape and only differ in the number/location of diacritical points. We conducted a masked priming lexical decision experiment in which a target word was preceded by: (i) an identity prime; (ii) a prime in which the critical letter was replaced by a letter with the same shape that differed in the number of diacritics (e.g., ); or (iii) a prime in which the critical letter was replaced by a letter with different shape (e.g., ). Results showed a sizable advantage of the identity condition over the two substituted-letter priming conditions (i.e., diacritical information is rapidly processed). Thus, diacritical marks play an essential role in the "feature letter" level of models of visual word recognition in Arabic. PMID:27597838

  9. Tracking the time course of phonetic cue integration during spoken word recognition.

    PubMed

    McMurray, Bob; Clayards, Meghan A; Tanenhaus, Michael K; Aslin, Richard N

    2008-12-01

    Speech perception requires listeners to integrate multiple cues that each contribute to judgments about a phonetic category. Classic studies of trading relations assessed the weights attached to each cue but did not explore the time course of cue integration. Here, we provide the first direct evidence that asynchronous cues to voicing (/b/ vs. /p/) and manner (/b/ vs. /w/) contrasts become available to the listener at different times during spoken word recognition. Using the visual world paradigm, we show that the probability of eye movements to pictures of target and of competitor objects diverge at different points in time after the onset of the target word. These points of divergence correspond to the availability of early (voice onset time or formant transition slope) and late (vowel length) cues to voicing and manner contrasts. These results support a model of cue integration in which phonetic cues are used for lexical access as soon as they are available. PMID:19001568

  10. Integration of Pragmatic and Phonetic Cues in Spoken Word Recognition

    PubMed Central

    Rohde, Hannah; Ettlinger, Marc

    2015-01-01

    Although previous research has established that multiple top-down factors guide the identification of words during speech processing, the ultimate range of information sources that listeners integrate from different levels of linguistic structure is still unknown. In a set of experiments, we investigate whether comprehenders can integrate information from the two most disparate domains: pragmatic inference and phonetic perception. Using contexts that trigger pragmatic expectations regarding upcoming coreference (expectations for either he or she), we test listeners' identification of phonetic category boundaries (using acoustically ambiguous words on the/hi/∼/∫i/continuum). The results indicate that, in addition to phonetic cues, word recognition also reflects pragmatic inference. These findings are consistent with evidence for top-down contextual effects from lexical, syntactic, and semantic cues, but they extend this previous work by testing cues at the pragmatic level and by eliminating a statistical-frequency confound that might otherwise explain the previously reported results. We conclude by exploring the time-course of this interaction and discussing how different models of cue integration could be adapted to account for our results. PMID:22250908

  11. Testing Saliency Parameters for Automatic Target Recognition

    NASA Technical Reports Server (NTRS)

    Pandya, Sagar

    2012-01-01

    A bottom-up visual attention model (the saliency model) is tested to enhance the performance of Automated Target Recognition (ATR). JPL has developed an ATR system that identifies regions of interest (ROI) using a trained OT-MACH filter, and then classifies potential targets as true- or false-positives using machine-learning techniques. In this project, saliency is used as a pre-processing step to reduce the space for performing OT-MACH filtering. Saliency parameters, such as output level and orientation weight, are tuned to detect known target features. Preliminary results are promising and future work entails a rigrous and parameter-based search to gain maximum insight about this method.

  12. Stimulus-driven changes in the direction of neural priming during visual word recognition.

    PubMed

    Pas, Maciej; Nakamura, Kimihiro; Sawamoto, Nobukatsu; Aso, Toshihiko; Fukuyama, Hidenao

    2016-01-15

    Visual object recognition is generally known to be facilitated when targets are preceded by the same or relevant stimuli. For written words, however, the beneficial effect of priming can be reversed when primes and targets share initial syllables (e.g., "boca" and "bono"). Using fMRI, the present study explored neuroanatomical correlates of this negative syllabic priming. In each trial, participants made semantic judgment about a centrally presented target, which was preceded by a masked prime flashed either to the left or right visual field. We observed that the inhibitory priming during reading was associated with a left-lateralized effect of repetition enhancement in the inferior frontal gyrus (IFG), rather than repetition suppression in the ventral visual region previously associated with facilitatory behavioral priming. We further performed a second fMRI experiment using a classical whole-word repetition priming paradigm with the same hemifield procedure and task instruction, and obtained well-known effects of repetition suppression in the left occipito-temporal cortex. These results therefore suggest that the left IFG constitutes a fast word processing system distinct from the posterior visual word-form system and that the directions of repetition effects can change with intrinsic properties of stimuli even when participants' cognitive and attentional states are kept constant. PMID:26514294

  13. Stimulus-driven changes in the direction of neural priming during visual word recognition.

    PubMed

    Pas, Maciej; Nakamura, Kimihiro; Sawamoto, Nobukatsu; Aso, Toshihiko; Fukuyama, Hidenao

    2016-01-15

    Visual object recognition is generally known to be facilitated when targets are preceded by the same or relevant stimuli. For written words, however, the beneficial effect of priming can be reversed when primes and targets share initial syllables (e.g., "boca" and "bono"). Using fMRI, the present study explored neuroanatomical correlates of this negative syllabic priming. In each trial, participants made semantic judgment about a centrally presented target, which was preceded by a masked prime flashed either to the left or right visual field. We observed that the inhibitory priming during reading was associated with a left-lateralized effect of repetition enhancement in the inferior frontal gyrus (IFG), rather than repetition suppression in the ventral visual region previously associated with facilitatory behavioral priming. We further performed a second fMRI experiment using a classical whole-word repetition priming paradigm with the same hemifield procedure and task instruction, and obtained well-known effects of repetition suppression in the left occipito-temporal cortex. These results therefore suggest that the left IFG constitutes a fast word processing system distinct from the posterior visual word-form system and that the directions of repetition effects can change with intrinsic properties of stimuli even when participants' cognitive and attentional states are kept constant.

  14. Offline handwritten word recognition using MQDF-HMMs

    NASA Astrophysics Data System (ADS)

    Ramachandrula, Sitaram; Hambarde, Mangesh; Patial, Ajay; Sahoo, Dushyant; Kochar, Shaivi

    2015-01-01

    We propose an improved HMM formulation for offline handwriting recognition (HWR). The main contribution of this work is using modified quadratic discriminant function (MQDF) [1] within HMM framework. In an MQDF-HMM the state observation likelihood is calculated by a weighted combination of MQDF likelihoods of individual Gaussians of GMM (Gaussian Mixture Model). The quadratic discriminant function (QDF) of a multivariate Gaussian can be rewritten by avoiding the inverse of covariance matrix by using the Eigen values and Eigen vectors of it. The MQDF is derived from QDF by substituting few of badly estimated lower-most Eigen values by an appropriate constant. The estimation errors of non-dominant Eigen vectors and Eigen values of covariance matrix for which the training data is insufficient can be controlled by this approach. MQDF has been successfully shown to improve the character recognition performance [1]. The usage of MQDF in HMM improves the computation, storage and modeling power of HMM when there is limited training data. We have got encouraging results on offline handwritten character (NIST database) and word recognition in English using MQDF HMMs.

  15. Parallel algorithms for isolated and connected word recognition. Volumes I and II

    SciTech Connect

    Yoder, M.A.

    1984-01-01

    For years researchers have worked toward finding a way to allow people to talk to machines in the same manner a person communicates to another person. This verbal man to machine interface, called speech recognition, can be grouped into three types: isolated word recognition, connected word recognition, and continuous speech recognition. Isolated word recognizers recognize single words with distinctive pauses before and after them. Continuous speech recognizers recognize speech spoken as one person speaks to another, continuously without pauses. Connected word recognition is an extension of isolated word recognition which recognizes groups of words spoken continuously. A group of words must have distinctive pauses before and after it, and the number of words in a group is limited to some small value (typically less than six). If these types of recognition systems are to be successful in the real world, they must be speaker independent and support a large vocabulary. They also must be able to recognize the speech input accurately and in real time. Currently there is no system which can meet all of these criteria because a vast amount of computations are needed. This thesis examines the use of parallel processing to reduce the computation time for speech recognition.

  16. A naturalistic study of the word frequency effect in episodic recognition.

    PubMed

    Chalmers, K A; Humphreys, M S; Dennis, S

    1997-11-01

    In order to separate the effects of experience from other characteristics of word frequency (e.g., orthographic distinctiveness), computer science and psychology students rated their experience with computer science technical items and nontechnical items from a wide range of word frequencies prior to being tested for recognition memory of the rated items. For nontechnical items, there was a curvilinear relationship between recognition accuracy and word frequency for both groups of students. The usual superiority of low-frequency words was demonstrated and high-frequency words were recognized least well. For technical items, a similar curvilinear relationship was evident for the psychology students, but for the computer science students, recognition accuracy was inversely related to word frequency. The ratings data showed that subjective experience rather than background word frequency was the better predictor of recognition accuracy. PMID:9421563

  17. Software for Partly Automated Recognition of Targets

    NASA Technical Reports Server (NTRS)

    Opitz, David; Blundell, Stuart; Bain, William; Morris, Matthew; Carlson, Ian; Mangrich, Mark

    2003-01-01

    The Feature Analyst is a computer program for assisted (partially automated) recognition of targets in images. This program was developed to accelerate the processing of high-resolution satellite image data for incorporation into geographic information systems (GIS). This program creates an advanced user interface that embeds proprietary machine-learning algorithms in commercial image-processing and GIS software. A human analyst provides samples of target features from multiple sets of data, then the software develops a data-fusion model that automatically extracts the remaining features from selected sets of data. The program thus leverages the natural ability of humans to recognize objects in complex scenes, without requiring the user to explain the human visual recognition process by means of lengthy software. Two major subprograms are the reactive agent and the thinking agent. The reactive agent strives to quickly learn the user s tendencies while the user is selecting targets and to increase the user s productivity by immediately suggesting the next set of pixels that the user may wish to select. The thinking agent utilizes all available resources, taking as much time as needed, to produce the most accurate autonomous feature-extraction model possible.

  18. Image understanding research for automatic target recognition

    SciTech Connect

    Bhanu, B. ); Jones, T.L. )

    1993-10-01

    Automatic Target Recognition (ATR) is an extremely important capability for defense applications. Many aspects of Image Understanding (IU) research are traditionally used to solve ATR problems. In this paper, the authors discuss ATR applications and problems in developing real-world ATR systems, and present the status of technology for these systems. They identify several IU problems that need to be resolved in order to enhance the effectiveness of ATR-based weapon systems. Finally, they conclude that technological gains in developing robust ATR systems will also lead to significant advances in many other areas of applications of image understanding.

  19. Words Jump-Start Vision: A Label Advantage in Object Recognition.

    PubMed

    Boutonnet, Bastien; Lupyan, Gary

    2015-06-24

    People use language to shape each other's behavior in highly flexible ways. Effects of language are often assumed to be "high-level" in that, whereas language clearly influences reasoning, decision making, and memory, it does not influence low-level visual processes. Here, we test the prediction that words are able to provide top-down guidance at the very earliest stages of visual processing by acting as powerful categorical cues. We investigated whether visual processing of images of familiar animals and artifacts was enhanced after hearing their name (e.g., "dog") compared with hearing an equally familiar and unambiguous nonverbal sound (e.g., a dog bark) in 14 English monolingual speakers. Because the relationship between words and their referents is categorical, we expected words to deploy more effective categorical templates, allowing for more rapid visual recognition. By recording EEGs, we were able to determine whether this label advantage stemmed from changes to early visual processing or later semantic decision processes. The results showed that hearing a word affected early visual processes and that this modulation was specific to the named category. An analysis of ERPs showed that the P1 was larger when people were cued by labels compared with equally informative nonverbal cues-an enhancement occurring within 100 ms of image onset, which also predicted behavioral responses occurring almost 500 ms later. Hearing labels modulated the P1 such that it distinguished between target and nontarget images, showing that words rapidly guide early visual processing.

  20. Words Jump-Start Vision: A Label Advantage in Object Recognition.

    PubMed

    Boutonnet, Bastien; Lupyan, Gary

    2015-06-24

    People use language to shape each other's behavior in highly flexible ways. Effects of language are often assumed to be "high-level" in that, whereas language clearly influences reasoning, decision making, and memory, it does not influence low-level visual processes. Here, we test the prediction that words are able to provide top-down guidance at the very earliest stages of visual processing by acting as powerful categorical cues. We investigated whether visual processing of images of familiar animals and artifacts was enhanced after hearing their name (e.g., "dog") compared with hearing an equally familiar and unambiguous nonverbal sound (e.g., a dog bark) in 14 English monolingual speakers. Because the relationship between words and their referents is categorical, we expected words to deploy more effective categorical templates, allowing for more rapid visual recognition. By recording EEGs, we were able to determine whether this label advantage stemmed from changes to early visual processing or later semantic decision processes. The results showed that hearing a word affected early visual processes and that this modulation was specific to the named category. An analysis of ERPs showed that the P1 was larger when people were cued by labels compared with equally informative nonverbal cues-an enhancement occurring within 100 ms of image onset, which also predicted behavioral responses occurring almost 500 ms later. Hearing labels modulated the P1 such that it distinguished between target and nontarget images, showing that words rapidly guide early visual processing. PMID:26109657

  1. Effects of age and hearing loss on the recognition of interrupted words in isolation and in sentences

    PubMed Central

    Kidd, Gary R.; Humes, Larry E.

    2012-01-01

    The ability to recognize spoken words interrupted by silence was investigated with young normal-hearing listeners and older listeners with and without hearing impairment. Target words from the revised SPIN test by Bilger et al. [J. Speech Hear. Res. 27(1), 32–48 (1984)] were presented in isolation and in the original sentence context using a range of interruption patterns in which portions of speech were replaced with silence. The number of auditory “glimpses” of speech and the glimpse proportion (total duration glimpsed/word duration) were varied using a subset of the SPIN target words that ranged in duration from 300 to 600 ms. The words were presented in isolation, in the context of low-predictability (LP) sentences, and in high-predictability (HP) sentences. The glimpse proportion was found to have a strong influence on word recognition, with relatively little influence of the number of glimpses, glimpse duration, or glimpse rate. Although older listeners tended to recognize fewer interrupted words, there was considerable overlap in recognition scores across listener groups in all conditions, and all groups were affected by interruption parameters and context in much the same way. PMID:22352515

  2. Modeling words with subword units in an articulatorily constrained speech recognition algorithm

    SciTech Connect

    Hogden, J.

    1997-11-20

    The goal of speech recognition is to find the most probable word given the acoustic evidence, i.e. a string of VQ codes or acoustic features. Speech recognition algorithms typically take advantage of the fact that the probability of a word, given a sequence of VQ codes, can be calculated.

  3. Talker and Lexical Effects on Audiovisual Word Recognition by Adults with Cochlear Implants.

    ERIC Educational Resources Information Center

    Kaiser, Adam R.; Kirk, Karen Iler; Lachs, Lorin; Pisoni, David B.

    2003-01-01

    A study examined how 20 adults with postlingual deafness with cochlear implants combined visual information from lip reading with auditory cues in an open-set word recognition task. Word recognition performance was highest for audiovisual presentation followed by auditory-only and then visual-only stimulus presentation, and for single-talker…

  4. Word Recognition Subcomponents and Passage Level Reading in a Foreign Language

    ERIC Educational Resources Information Center

    Yamashita, Junko

    2013-01-01

    Despite the growing number of studies highlighting the complex process of acquiring second language (L2) word recognition skills, comparatively little research has examined the relationship between word recognition and passage-level reading ability in L2 learners; further, the existing results are inconclusive. This study aims to help fill the…

  5. Morphing Images: A Potential Tool for Teaching Word Recognition to Children with Severe Learning Difficulties

    ERIC Educational Resources Information Center

    Sheehy, Kieron

    2005-01-01

    Children with severe learning difficulties who fail to begin word recognition can learn to recognise pictures and symbols relatively easily. However, finding an effective means of using pictures to teach word recognition has proved problematic. This research explores the use of morphing software to support the transition from picture to word…

  6. Relations among Linguistic and Cognitive Skills and Spoken Word Recognition in Adults with Cochlear Implants

    ERIC Educational Resources Information Center

    Collison, Elizabeth A.; Munson, Benjamin; Carney, Arlene Earley

    2004-01-01

    This study examined spoken word recognition in adults with cochlear implants (CIs) to determine the extent to which linguistic and cognitive abilities predict variability in speech-perception performance. Both a traditional consonant-vowel-consonant (CVC)-repetition measure and a gated-word recognition measure (F. Grosjean, 1996) were used.…

  7. The Predictive Power of Phonemic Awareness and Naming Speed for Early Dutch Word Recognition

    ERIC Educational Resources Information Center

    Verhagen, Wim G. M.; Aarnoutse, Cor A. J.; van Leeuwe, Jan F. J.

    2009-01-01

    Effects of phonemic awareness and naming speed on the speed and accuracy of Dutch children's word recognition were investigated in a longitudinal study. Both the speed and accuracy of word recognition at the end of Grade 2 were predicted by naming speed from both kindergarten and Grade 1, after control for autoregressive relations, kindergarten…

  8. Phonological Awareness and Naming Speed in the Prediction of Dutch Children's Word Recognition

    ERIC Educational Resources Information Center

    Verhagen, W.; Aarnoutse, C.; van Leeuwe, J.

    2008-01-01

    Influences of phonological awareness and naming speed on the speed and accuracy of Dutch children's word recognition were investigated in a longitudinal study. The speed and accuracy of word recognition at the ends of Grades 1 and 2 were predicted by naming speed from both the beginning and end of Grade 1, after control for autoregressive…

  9. Locus of Orthographic Effects in Spoken Word Recognition: Novel Insights from the Neighbour Generation Task

    ERIC Educational Resources Information Center

    Muneaux, Mathilde; Ziegler, Johannes C.

    2004-01-01

    Previous research has found that orthographic information can influence auditory word recognition. However, there is still debate about the locus of this effect (lexical versus nonlexical, strategic versus automatic). In the present study, we explored whether orthographic effects in auditory word recognition could be structural-residual effects…

  10. Concurrent Correlates of Chinese Word Recognition in Deaf and Hard-of-Hearing Children

    ERIC Educational Resources Information Center

    Ching, Boby Ho-Hong; Nunes, Terezinha

    2015-01-01

    The aim of this study was to explore the relative contributions of phonological, semantic radical, and morphological awareness to Chinese word recognition in deaf and hard-of-hearing (DHH) children. Measures of word recognition, general intelligence, phonological, semantic radical, and morphological awareness were administered to 32 DHH and 35…

  11. The Effects of Explicit Word Recognition Training on Japanese EFL Learners

    ERIC Educational Resources Information Center

    Burrows, Lance; Holsworth, Michael

    2016-01-01

    This study is a quantitative, quasi-experimental investigation focusing on the effects of word recognition training on word recognition fluency, reading speed, and reading comprehension for 151 Japanese university students at a lower-intermediate reading proficiency level. Four treatment groups were given training in orthographic, phonological,…

  12. An Experimental Program for Teaching High Speed Word Recognition and Comprehension Skills. Final Report.

    ERIC Educational Resources Information Center

    Dahl, Patricia J. Rawerts

    This study was concerned with the development of a program for teaching high speed word recognition through training in more sophisticated decoding strategies. The method reported focused on training the student to use minimal visual information while making maximum use of contextual cues in word recognition. The emphasis was on directing…

  13. Knowledge of a Second Language Influences Auditory Word Recognition in the Native Language

    ERIC Educational Resources Information Center

    Lagrou, Evelyne; Hartsuiker, Robert J.; Duyck, Wouter

    2011-01-01

    Many studies in bilingual visual word recognition have demonstrated that lexical access is not language selective. However, research on bilingual word recognition in the auditory modality has been scarce, and it has yielded mixed results with regard to the degree of this language nonselectivity. In the present study, we investigated whether…

  14. Individual Differences in Visual Word Recognition: Insights from the English Lexicon Project

    ERIC Educational Resources Information Center

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

    2012-01-01

    Empirical work and models of visual word recognition have traditionally focused on group-level performance. Despite the emphasis on the prototypical reader, there is clear evidence that variation in reading skill modulates word recognition performance. In the present study, we examined differences among individuals who contributed to the English…

  15. Emotion word recognition: discrete information effects first, continuous later?

    PubMed

    Briesemeister, Benny B; Kuchinke, Lars; Jacobs, Arthur M

    2014-05-20

    Manipulations of either discrete emotions (e.g. happiness) or affective dimensions (e.g. positivity) have a long tradition in emotion research, but interactive effects have never been studied, based on the assumption that the two underlying theories are incompatible. Recent theorizing suggests, however, that the human brain relies on two affective processing systems, one working on the basis of discrete emotion categories, and the other working along affective dimensions. Presenting participants with an orthogonal manipulation of happiness and positivity in a lexical decision task, the present study meant to test the appropriateness of this assumption in emotion word recognition. Behavioral and electroencephalographic data revealed independent effects for both variables, with happiness affecting the early visual N1 component, while positivity affected an N400-like component and the late positive complex. These results are interpreted as evidence for a sequential processing of affective information, with discrete emotions being the basis for later dimensional appraisal processes. PMID:24713350

  16. Knowledge of a second language influences auditory word recognition in the native language.

    PubMed

    Lagrou, Evelyne; Hartsuiker, Robert J; Duyck, Wouter

    2011-07-01

    Many studies in bilingual visual word recognition have demonstrated that lexical access is not language selective. However, research on bilingual word recognition in the auditory modality has been scarce, and it has yielded mixed results with regard to the degree of this language nonselectivity. In the present study, we investigated whether listening to a second language (L2) is influenced by knowledge of the native language (L1) and, more important, whether listening to the L1 is also influenced by knowledge of an L2. Additionally, we investigated whether the listener's selectivity of lexical access is influenced by the speaker's L1 (and thus his or her accent). With this aim, Dutch-English bilinguals completed an English (Experiment 1) and a Dutch (Experiment 3) auditory lexical decision task. As a control, the English auditory lexical decision task was also completed by English monolinguals (Experiment 2). Targets were pronounced by a native Dutch speaker with English as the L2 (Experiments 1A, 2A, and 3A) or by a native English speaker with Dutch as the L2 (Experiments 1B, 2B, and 3B). In all experiments, Dutch-English bilinguals recognized interlingual homophones (e.g., lief [sweet]-leaf /li:f/) significantly slower than matched control words, whereas the English monolinguals showed no effect. These results indicate that (a) lexical access in bilingual auditory word recognition is not language selective in L2, nor in L1, and (b) language-specific subphonological cues do not annul cross-lingual interactions.

  17. Evaluating word representation features in biomedical named entity recognition tasks.

    PubMed

    Tang, Buzhou; Cao, Hongxin; Wang, Xiaolong; Chen, Qingcai; Xu, Hua

    2014-01-01

    Biomedical Named Entity Recognition (BNER), which extracts important entities such as genes and proteins, is a crucial step of natural language processing in the biomedical domain. Various machine learning-based approaches have been applied to BNER tasks and showed good performance. In this paper, we systematically investigated three different types of word representation (WR) features for BNER, including clustering-based representation, distributional representation, and word embeddings. We selected one algorithm from each of the three types of WR features and applied them to the JNLPBA and BioCreAtIvE II BNER tasks. Our results showed that all the three WR algorithms were beneficial to machine learning-based BNER systems. Moreover, combining these different types of WR features further improved BNER performance, indicating that they are complementary to each other. By combining all the three types of WR features, the improvements in F-measure on the BioCreAtIvE II GM and JNLPBA corpora were 3.75% and 1.39%, respectively, when compared with the systems using baseline features. To the best of our knowledge, this is the first study to systematically evaluate the effect of three different types of WR features for BNER tasks.

  18. A novel thermal face recognition approach using face pattern words

    NASA Astrophysics Data System (ADS)

    Zheng, Yufeng

    2010-04-01

    A reliable thermal face recognition system can enhance the national security applications such as prevention against terrorism, surveillance, monitoring and tracking, especially at nighttime. The system can be applied at airports, customs or high-alert facilities (e.g., nuclear power plant) for 24 hours a day. In this paper, we propose a novel face recognition approach utilizing thermal (long wave infrared) face images that can automatically identify a subject at both daytime and nighttime. With a properly acquired thermal image (as a query image) in monitoring zone, the following processes will be employed: normalization and denoising, face detection, face alignment, face masking, Gabor wavelet transform, face pattern words (FPWs) creation, face identification by similarity measure (Hamming distance). If eyeglasses are present on a subject's face, an eyeglasses mask will be automatically extracted from the querying face image, and then masked with all comparing FPWs (no more transforms). A high identification rate (97.44% with Top-1 match) has been achieved upon our preliminary face dataset (of 39 subjects) from the proposed approach regardless operating time and glasses-wearing condition.e

  19. Additive and Interactive Effects on Response Time Distributions in Visual Word Recognition

    ERIC Educational Resources Information Center

    Yap, Melvin J.; Balota, David A.

    2007-01-01

    Across 3 different word recognition tasks, distributional analyses were used to examine the joint effects of stimulus quality and word frequency on underlying response time distributions. Consistent with the extant literature, stimulus quality and word frequency produced additive effects in lexical decision, not only in the means but also in the…

  20. A Prerequisite to L1 Homophone Effects in L2 Spoken-Word Recognition

    ERIC Educational Resources Information Center

    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…

  1. The Effect of the Balance of Orthographic Neighborhood Distribution in Visual Word Recognition

    ERIC Educational Resources Information Center

    Robert, Christelle; Mathey, Stephanie; Zagar, Daniel

    2007-01-01

    The present study investigated whether the balance of neighborhood distribution (i.e., the way orthographic neighbors are spread across letter positions) influences visual word recognition. Three word conditions were compared. Word neighbors were either concentrated on one letter position (e.g.,nasse/basse-lasse-tasse-masse) or were unequally…

  2. Orthographic Consistency Affects Spoken Word Recognition at Different Grain-Sizes

    ERIC Educational Resources Information Center

    Dich, Nadya

    2014-01-01

    A number of previous studies found that the consistency of sound-to-spelling mappings (feedback consistency) affects spoken word recognition. In auditory lexical decision experiments, words that can only be spelled one way are recognized faster than words with multiple potential spellings. Previous studies demonstrated this by manipulating…

  3. Extraction of words from the national ID cards for automated recognition

    NASA Astrophysics Data System (ADS)

    Akhter, Md. Rezwan; Bhuiyan, Md. Hasanuzzaman; Uddin, Mohammad Shorif

    2011-10-01

    The government of Bangladesh introduced national ID cards in 2008 for all peoples of age 18 years and above. This card is now a de-facto identity document and finds diverse applications in vote casting, bank account opening, telephone subscribing as well as in many real life transactions and security checking. To get real fruits of this versatile ID card, automated retrieving and recognition of an independent person from this extra large national database is an ultimate necessity. This work is the first step to fill this gap in making the recognition in automated fashion. Here we have investigated an image analysis technique to extract the words that will be used in subsequent recognition steps. At first scanned ID card image is used as an input into the computer system and then the target text region is separated from the picture region. The text region is used for separation of lines and words on the basis of the vertical and horizontal projections of image intensity, respectively. Experimentation using real national ID cards confirms the effectiveness of our technique.

  4. Age of Acquisition and Sensitivity to Gender in Spanish Word Recognition

    ERIC Educational Resources Information Center

    Foote, Rebecca

    2014-01-01

    Speakers of gender-agreement languages use gender-marked elements of the noun phrase in spoken-word recognition: A congruent marking on a determiner or adjective facilitates the recognition of a subsequent noun, while an incongruent marking inhibits its recognition. However, while monolinguals and early language learners evidence this…

  5. Hemispheric asymmetries in word recognition as revealed by the orthographic uniqueness point effect.

    PubMed

    Izura, Cristina; Wright, Victoria C; Fouquet, Nathalie

    2014-01-01

    The orthographic uniqueness point (OUP) refers to the first letter of a word that, reading from left to right, makes the word unique. It has recently been proposed that OUPs might be relevant in word recognition and their influence could inform the long-lasting debate of whether - and to what extent - printed words are recognized serially or in parallel. The present study represents the first investigation of the neural and behavioral effects of OUP on visual word recognition. Behaviourally, late OUP words were identified faster and more accurately in a lexical decision task. Analysis of event-related potentials demonstrated a hemispheric asymmetry on the N170 component, with the left hemisphere appearing to be more sensitive to the position of the OUP within a word than the right hemisphere. These results suggest that processing of centrally presented words is likely to occur in a partially parallel manner, as an ends-in scanning process.

  6. A real-time optical automatic target recognition system

    NASA Astrophysics Data System (ADS)

    Chen, Huaixin; Nan, Jianshe; Li, Xiaosun; Wei, Honggang

    2004-04-01

    Automatic target recognition (ATR) technique has been applied in both civil and military. In this paper, we present a new optical pattern recognition system for target recognition. This system includes synthetic discriminate function (SDF) based practical optimized filters for the 3-D targets, the Reference Filter Libs for high correlation SNR, the mapping between the input (object regions) and the output (correlation peaks), and neural networks (ANN) for final decision making. The Real-time optical target recognition is realized by temporal multiplexing technique with electronic addressing spatial light modulator. The experiment results show that the proposed OPR system is efficient and reliable.

  7. Cognitive control and word recognition speed influence the Stroop effect in bilinguals.

    PubMed

    Wang, Ruiming; Fan, Xiaoyue; Liu, Cong; Cai, Zhenguang G

    2016-04-01

    Bilinguals have been shown to be less susceptible to Stroop interference in their first language than monolinguals, though the cause is currently being debated. In two experiments, we explored how cognitive control and word recognition contribute to the Stroop effect by contrasting cognitive control (via a Simon arrow task), word recognition speed (via a Chinese/English word recognition task) and Stroop susceptibility (via a verbal Stroop task) between proficient and non-proficient Chinese-English bilinguals. Compared to non-proficient bilinguals, proficient bilinguals showed better cognitive control at inhibiting irrelevant information, and they were slower at recognising Chinese words but quicker at recognising English words. Critically, we also showed that proficient bilinguals showed a smaller Stroop effect than non-proficient bilinguals in Chinese but a comparable Stroop effect as non-proficient bilinguals in English. The results cannot be accounted for by cognitive control or word recognition speed alone; instead, they are best accommodated by assuming that cognitive control and word recognition speed jointly determine the Stroop effect. Thus, we conclude that enhanced cognitive control and delayed word recognition combine to reduce Stroop effect in bilinguals as compared to monolinguals.

  8. The modulation of semantic transparency on the recognition memory for two-character Chinese words.

    PubMed

    Han, Yi-Jhong; Huang, Shuo-Chieh; Lee, Chia-Ying; Kuo, Wen-Jui; Cheng, Shih-Kuen

    2014-11-01

    This study demonstrated that semantic transparency as a linguistic property modulates the recognition memory for two-character Chinese words, with opaque words (i.e., words whose meanings cannot be derived from constituent characters-e.g., "[/guang/, light][/gun/, stick]", bachelor) remembered better than transparent words (i.e., words whose meanings can be derived from constituent characters-e.g., "[/cha/, tea][/bei/, cup]", teacup). In Experiment 1, the participants made lexical decisions on transparent words, opaque words, and nonwords in the study and then engaged in an old/new recognition test. Experiment 2 employed a concreteness judgment as the encoding task to ensure equivalent semantic processing for opaque and transparent words. In Experiment 3, the neighborhood size of the two-character words was manipulated together with their semantic transparency. In all three experiments, opaque words were found to be better remembered than transparent words. We concluded that the conceptual incongruence between the meanings of a whole word and its constituent characters made opaque words more distinctive and, hence, better remembered than transparent words.

  9. Speed and accuracy of dyslexic versus typical word recognition: an eye-movement investigation

    PubMed Central

    Kunert, Richard; Scheepers, Christoph

    2014-01-01

    Developmental dyslexia is often characterized by a dual deficit in both word recognition accuracy and general processing speed. While previous research into dyslexic word recognition may have suffered from speed-accuracy trade-off, the present study employed a novel eye-tracking task that is less prone to such confounds. Participants (10 dyslexics and 12 controls) were asked to look at real word stimuli, and to ignore simultaneously presented non-word stimuli, while their eye-movements were recorded. Improvements in word recognition accuracy over time were modeled in terms of a continuous non-linear function. The words' rhyme consistency and the non-words' lexicality (unpronounceable, pronounceable, pseudohomophone) were manipulated within-subjects. Speed-related measures derived from the model fits confirmed generally slower processing in dyslexics, and showed a rhyme consistency effect in both dyslexics and controls. In terms of overall error rate, dyslexics (but not controls) performed less accurately on rhyme-inconsistent words, suggesting a representational deficit for such words in dyslexics. Interestingly, neither group showed a pseudohomophone effect in speed or accuracy, which might call the task-independent pervasiveness of this effect into question. The present results illustrate the importance of distinguishing between speed- vs. accuracy-related effects for our understanding of dyslexic word recognition. PMID:25346708

  10. Speed and accuracy of dyslexic versus typical word recognition: an eye-movement investigation.

    PubMed

    Kunert, Richard; Scheepers, Christoph

    2014-01-01

    Developmental dyslexia is often characterized by a dual deficit in both word recognition accuracy and general processing speed. While previous research into dyslexic word recognition may have suffered from speed-accuracy trade-off, the present study employed a novel eye-tracking task that is less prone to such confounds. Participants (10 dyslexics and 12 controls) were asked to look at real word stimuli, and to ignore simultaneously presented non-word stimuli, while their eye-movements were recorded. Improvements in word recognition accuracy over time were modeled in terms of a continuous non-linear function. The words' rhyme consistency and the non-words' lexicality (unpronounceable, pronounceable, pseudohomophone) were manipulated within-subjects. Speed-related measures derived from the model fits confirmed generally slower processing in dyslexics, and showed a rhyme consistency effect in both dyslexics and controls. In terms of overall error rate, dyslexics (but not controls) performed less accurately on rhyme-inconsistent words, suggesting a representational deficit for such words in dyslexics. Interestingly, neither group showed a pseudohomophone effect in speed or accuracy, which might call the task-independent pervasiveness of this effect into question. The present results illustrate the importance of distinguishing between speed- vs. accuracy-related effects for our understanding of dyslexic word recognition. PMID:25346708

  11. Comparison of crisp and fuzzy character networks in handwritten word recognition

    NASA Technical Reports Server (NTRS)

    Gader, Paul; Mohamed, Magdi; Chiang, Jung-Hsien

    1992-01-01

    Experiments involving handwritten word recognition on words taken from images of handwritten address blocks from the United States Postal Service mailstream are described. The word recognition algorithm relies on the use of neural networks at the character level. The neural networks are trained using crisp and fuzzy desired outputs. The fuzzy outputs were defined using a fuzzy k-nearest neighbor algorithm. The crisp networks slightly outperformed the fuzzy networks at the character level but the fuzzy networks outperformed the crisp networks at the word level.

  12. The Influence of the Phonological Neighborhood Clustering Coefficient on Spoken Word Recognition

    ERIC Educational Resources Information Center

    Chan, Kit Ying; Vitevitch, Michael S.

    2009-01-01

    Clustering coefficient--a measure derived from the new science of networks--refers to the proportion of phonological neighbors of a target word that are also neighbors of each other. Consider the words "bat", "hat", and "can", all of which are neighbors of the word "cat"; the words "bat" and "hat" are also neighbors of each other. In a perceptual…

  13. Remote weapon station for automatic target recognition system demand analysis

    NASA Astrophysics Data System (ADS)

    Lei, Zhang; Li, Sheng-cai; Shi, Cai

    2015-08-01

    Introduces a remote weapon station basic composition and the main advantage, analysis of target based on image automatic recognition system for remote weapon station of practical significance, the system elaborated the image based automatic target recognition system in the photoelectric stabilized technology, multi-sensor image fusion technology, integrated control target image enhancement, target behavior risk analysis technology, intelligent based on the character of the image automatic target recognition algorithm research, micro sensor technology as the key technology of the development in the field of demand.

  14. Recognition memory for Braille or spoken words: an fMRI study in early blind.

    PubMed

    Burton, Harold; Sinclair, Robert J; Agato, Alvin

    2012-02-15

    We examined cortical activity in early blind during word recognition memory. Nine participants were blind at birth and one by 1.5years. In an event-related design, we studied blood oxygen level-dependent responses to studied ("old") compared to novel ("new") words. Presentation mode was in Braille or spoken. Responses were larger for identified "new" words read with Braille in bilateral lower and higher tier visual areas and primary somatosensory cortex. Responses to spoken "new" words were larger in bilateral primary and accessory auditory cortex. Auditory cortex was unresponsive to Braille words and occipital cortex responded to spoken words but not differentially with "old"/"new" recognition. Left dorsolateral prefrontal cortex had larger responses to "old" words only with Braille. Larger occipital cortex responses to "new" Braille words suggested verbal memory based on the mechanism of recollection. A previous report in sighted noted larger responses for "new" words studied in association with pictures that created a distinctiveness heuristic source factor which enhanced recollection during remembering. Prior behavioral studies in early blind noted an exceptional ability to recall words. Utilization of this skill by participants in the current study possibly engendered recollection that augmented remembering "old" words. A larger response when identifying "new" words possibly resulted from exhaustive recollecting the sensory properties of "old" words in modality appropriate sensory cortices. The uniqueness of a memory role for occipital cortex is in its cross-modal responses to coding tactile properties of Braille. The latter possibly reflects a "sensory echo" that aids recollection.

  15. Automatic target recognition apparatus and method

    DOEpatents

    Baumgart, Chris W.; Ciarcia, Christopher A.

    2000-01-01

    An automatic target recognition apparatus (10) is provided, having a video camera/digitizer (12) for producing a digitized image signal (20) representing an image containing therein objects which objects are to be recognized if they meet predefined criteria. The digitized image signal (20) is processed within a video analysis subroutine (22) residing in a computer (14) in a plurality of parallel analysis chains such that the objects are presumed to be lighter in shading than the background in the image in three of the chains and further such that the objects are presumed to be darker than the background in the other three chains. In two of the chains the objects are defined by surface texture analysis using texture filter operations. In another two of the chains the objects are defined by background subtraction operations. In yet another two of the chains the objects are defined by edge enhancement processes. In each of the analysis chains a calculation operation independently determines an error factor relating to the probability that the objects are of the type which should be recognized, and a probability calculation operation combines the results of the analysis chains.

  16. Electrophysiological assessment of the time course of bilingual visual word recognition: Early access to language membership.

    PubMed

    Yiu, Loretta K; Pitts, Michael A; Canseco-Gonzalez, Enriqueta

    2015-08-01

    Previous research examining the time course of lexical access during word recognition suggests that phonological processing precedes access to semantic information, which in turn precedes access to syntactic information. Bilingual word recognition likely requires an additional level: knowledge of which language a specific word belongs to. Using the recording of event-related potentials, we investigated the time course of access to language membership information relative to semantic (Experiment 1) and syntactic (Experiment 2) encoding during visual word recognition. In Experiment 1, Spanish-English bilinguals viewed a series of printed words while making dual-choice go/nogo and left/right hand decisions based on semantic (whether the word referred to an animal or an object) and language membership information (whether the word was in English or in Spanish). Experiment 2 used a similar paradigm but with syntactic information (whether the word was a noun or a verb) as one of the response contingencies. The onset and peak latency of the N200, a component related to response inhibition, indicated that language information is accessed earlier than semantic information. Similarly, language information was also accessed earlier than syntactic information (but only based on peak latency). We discuss these findings with respect to models of bilingual word recognition and language comprehension in general.

  17. Gaze position reveals impaired attentional shift during visual word recognition in dysfluent readers.

    PubMed

    Hautala, Jarkko; Parviainen, Tiina

    2014-01-01

    Effects reflecting serial within-word processing are frequently found in pseudo- and non-word recognition tasks not only among fluent, but especially among dyslexic readers. However, the time course and locus of these serial within-word processing effects in the cognitive hierarchy (i.e., orthographic, phonological, lexical) have remained elusive. We studied whether a subject's eye movements during a lexical decision task would provide information about the temporal dynamics of serial within-word processing. We assumed that if there is serial within-word processing proceeding from left to right, items with informative beginnings would attract the gaze position and (micro-)saccadic eye movements earlier in time relative to those with informative endings. In addition, we compared responses to word, non-word, and pseudo-word items to study whether serial within-word processing stems mainly from a lexical, orthographic, or phonological processing level, respectively. Gaze positions showed earlier responses to anomalies located at pseudo- and non-word beginnings rather than endings, whereas informative word beginnings or endings did not affect gaze positions. The overall pattern of results suggests parallel letter processing of real words and rapid serial within-word processing when reading novel words. Dysfluent readers' gaze position responses toward anomalies located at pseudo- and non-word endings were delayed substantially, suggesting impairment in serial processing at an orthographic processing level.

  18. Gaze Position Reveals Impaired Attentional Shift during Visual Word Recognition in Dysfluent Readers

    PubMed Central

    Hautala, Jarkko; Parviainen, Tiina

    2014-01-01

    Effects reflecting serial within-word processing are frequently found in pseudo- and non-word recognition tasks not only among fluent, but especially among dyslexic readers. However, the time course and locus of these serial within-word processing effects in the cognitive hierarchy (i.e., orthographic, phonological, lexical) have remained elusive. We studied whether a subject's eye movements during a lexical decision task would provide information about the temporal dynamics of serial within-word processing. We assumed that if there is serial within-word processing proceeding from left to right, items with informative beginnings would attract the gaze position and (micro-)saccadic eye movements earlier in time relative to those with informative endings. In addition, we compared responses to word, non-word, and pseudo-word items to study whether serial within-word processing stems mainly from a lexical, orthographic, or phonological processing level, respectively. Gaze positions showed earlier responses to anomalies located at pseudo- and non-word beginnings rather than endings, whereas informative word beginnings or endings did not affect gaze positions. The overall pattern of results suggests parallel letter processing of real words and rapid serial within-word processing when reading novel words. Dysfluent readers' gaze position responses toward anomalies located at pseudo- and non-word endings were delayed substantially, suggesting impairment in serial processing at an orthographic processing level. PMID:25268909

  19. Computational Modeling of Morphological Effects in Bangla Visual Word Recognition

    ERIC Educational Resources Information Center

    Dasgupta, Tirthankar; Sinha, Manjira; Basu, Anupam

    2015-01-01

    In this paper we aim to model the organization and processing of Bangla polymorphemic words in the mental lexicon. Our objective is to determine whether the mental lexicon accesses a polymorphemic word as a whole or decomposes the word into its constituent morphemes and then recognize them accordingly. To address this issue, we adopted two…

  20. Encoding and contextual components of word recognition in good and poor readers.

    PubMed

    Simpson, G B; Lorsbach, T C; Whitehouse, D

    1983-02-01

    Good and poor readers from the third and sixth grades (9- and 12-year-olds, respectively), named visually presented words as rapidly as possible. Words were in clear or degraded form, and were preceded by related or unrelated words. Poor readers were hurt more by degradation than were good readers, and showed greater benefit from context. In general, the contextual benefit was greater with degraded words than with intact, and this interaction was especially pronounced in the poor readers. The results are consistent with an interactive-compensatory model of word recognition. Under conditions in which stimulus encoding is slow, contextual factors may compensate for this encoding deficit.

  1. Age-of-Acquisition Effects in Visual Word Recognition: Evidence from Expert Vocabularies

    ERIC Educational Resources Information Center

    Stadthagen-Gonzalez, Hans; Bowers, Jeffrey S.; Damian, Markus F.

    2004-01-01

    Three experiments assessed the contributions of age-of-acquisition (AoA) and frequency to visual word recognition. Three databases were created from electronic journals in chemistry, psychology and geology in order to identify technical words that are extremely frequent in each discipline but acquired late in life. In Experiment 1, psychologists…

  2. Hearing Status and Language Fluency as Predictors of Automatic Word and Sign Recognition.

    ERIC Educational Resources Information Center

    Marschark, Marc; Shroyer, Edgar H.

    1993-01-01

    This study of the automatic word and sign recognition of 66 hearing and deaf adults found that responding in sign took longer and created more Stroop interference than responding orally, independent of hearing status. Deaf subjects showed greater automaticity in recognizing signs than words, whereas hearing subjects showed greater automaticity in…

  3. Evaluating a Split Processing Model of Visual Word Recognition: Effects of Orthographic Neighborhood Size

    ERIC Educational Resources Information Center

    Lavidor, Michal; Hayes, Adrian; Shillcock, Richard; Ellis, Andrew W.

    2004-01-01

    The split fovea theory proposes that visual word recognition of centrally presented words is mediated by the splitting of the foveal image, with letters to the left of fixation being projected to the right hemisphere (RH) and letters to the right of fixation being projected to the left hemisphere (LH). Two lexical decision experiments aimed to…

  4. Re-Evaluating Split-Fovea Processing in Word Recognition: A Critical Assessment of Recent Research

    ERIC Educational Resources Information Center

    Jordan, Timothy R.; Paterson, Kevin B.

    2009-01-01

    In recent years, some researchers have proposed that a fundamental component of the word recognition process is that each fovea is divided precisely at its vertical midline and that information either side of this midline projects to different, contralateral hemispheres. Thus, when a word is fixated, all letters to the left of the point of…

  5. The Effects of Semantic Transparency and Base Frequency on the Recognition of English Complex Words

    ERIC Educational Resources Information Center

    Xu, Joe; Taft, Marcus

    2015-01-01

    A visual lexical decision task was used to examine the interaction between base frequency (i.e., the cumulative frequencies of morphologically related forms) and semantic transparency for a list of derived words. Linear mixed effects models revealed that high base frequency facilitates the recognition of the complex word (i.e., a "base…

  6. Is Syntactic-Category Processing Obligatory in Visual Word Recognition? Evidence from Chinese

    ERIC Educational Resources Information Center

    Wong, Andus Wing-Kuen; Chen, Hsuan-Chih

    2012-01-01

    Three experiments were conducted to investigate how syntactic-category and semantic information is processed in visual word recognition. The stimuli were two-character Chinese words in which semantic and syntactic-category ambiguities were factorially manipulated. A lexical decision task was employed in Experiment 1, whereas a semantic relatedness…

  7. Lexical-Semantic Processing and Reading: Relations between Semantic Priming, Visual Word Recognition and Reading Comprehension

    ERIC Educational Resources Information Center

    Nobre, Alexandre de Pontes; de Salles, Jerusa Fumagalli

    2016-01-01

    The aim of this study was to investigate relations between lexical-semantic processing and two components of reading: visual word recognition and reading comprehension. Sixty-eight children from private schools in Porto Alegre, Brazil, from 7 to 12 years, were evaluated. Reading was assessed with a word/nonword reading task and a reading…

  8. Investigating an Innovative Computer Application to Improve L2 Word Recognition from Speech

    ERIC Educational Resources Information Center

    Matthews, Joshua; O'Toole, John Mitchell

    2015-01-01

    The ability to recognise words from the aural modality is a critical aspect of successful second language (L2) listening comprehension. However, little research has been reported on computer-mediated development of L2 word recognition from speech in L2 learning contexts. This report describes the development of an innovative computer application…

  9. Genetic and Environmental Influences on Individual Differences in Printed Word Recognition.

    ERIC Educational Resources Information Center

    Gayan, Javier; Olson, Richard K.

    2003-01-01

    Explored genetic and environmental etiologies of individual differences in printed word recognition and related skills in identical and fraternal twin 8- to 18-year-olds. Found evidence for moderate genetic influences common between IQ, phoneme awareness, and word-reading skills and for stronger IQ-independent genetic influences that were common…

  10. Spoken Word Recognition in Adolescents with Autism Spectrum Disorders and Specific Language Impairment

    ERIC Educational Resources Information Center

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

    2013-01-01

    Spoken word recognition, during gating, appears intact in specific language impairment (SLI). This study used gating to investigate the process in adolescents with autism spectrum disorders plus language impairment (ALI). Adolescents with ALI, SLI, and typical language development (TLD), matched on nonverbal IQ listened to gated words that varied…

  11. N170 ERPs could represent a logographic processing strategy in visual word recognition

    PubMed Central

    Simon, Gregory; Petit, Laurent; Bernard, Christian; Rebaï, Mohamed

    2007-01-01

    Background Occipito-temporal N170 component represents the first step where face, object and word processing are discriminated along the ventral stream of the brain. N170 leftward asymmetry observed during reading has been often associated to prelexical orthographic visual word form activation. However, some studies reported a lexical frequency effect for this component particularly during word repetition that appears in contradiction with this prelexical orthographic step. Here, we tested the hypothesis that under word repetition condition, discrimination between words would be operated on visual rather than orthographic basis. In this case, N170 activity may correspond to a logographic processing where a word is processed as a whole. Methods To test such an assumption, frequent words, infrequent words and pseudowords were presented to the subjects that had to complete a visual lexical decision task. Different repetition conditions were defined 1 – weak repetition, 2 – massive repetition and 3 – massive repetition with font alternation. This last condition was designed to change visual word shape during repetition and therefore to interfere with a possible visual strategy during word recognition. Results Behavioral data showed an important frequency effect for the weak repetition condition, a lower but significant frequency effect for massive repetition, and no frequency effect for the changing font repetition. Moreover alternating font repetitions slowed subject's responses in comparison to "simple" massive repetition. ERPs results evidenced larger N170 amplitude in the left hemisphere for frequent than both infrequent words and pseudowords during massive repetition. Moreover, when words were repeated with different fonts this N170 effect was not present, suggesting a visual locus for such a N170 frequency effect. Conclusion N170 represents an important step in visual word recognition, consisting probably in a prelexical orthographic processing. But during

  12. Song Recognition among Preschool-Age Children: An Investigation of Words and Music.

    ERIC Educational Resources Information Center

    Feierabend, John M.; Saunders, T. Clark; Getnick, Pamela E.; Holahan, John M.

    1998-01-01

    Seeks to discover whether listening to songs over an extended period of time contributes to a greater integration of words and music in memory among preschool children. Finds more accurate recognition of songs performed without text when they had heard them previously with texts and that melodic content influenced song-recognition ability. (DSK)

  13. Latent Variable Modeling of Cognitive Processes in True and False Recognition of Words: A Developmental Perspective

    ERIC Educational Resources Information Center

    Bouwmeester, Samantha; Verkoeijen, Peter P. J. L.

    2010-01-01

    The present study aimed at testing theoretical predictions of the fuzzy-trace theory about true and false recognition. The effects of semantic relatedness and study opportunity on true and false recognition of words from Deese, Roediger, McDermott lists (J. Deese, 1959; D. R. Read, 1996; H. L. Roediger & K. B. McDermott, 1995) were evaluated in 7-…

  14. Effects of audio-visual presentation of target words in word translation training

    NASA Astrophysics Data System (ADS)

    Akahane-Yamada, Reiko; Komaki, Ryo; Kubo, Rieko

    2001-05-01

    Komaki and Akahane-Yamada (Proc. ICA2004) used 2AFC translation task in vocabulary training, in which the target word is presented visually in orthographic form of one language, and the appropriate meaning in another language has to be chosen between two choices. Present paper examined the effect of audio-visual presentation of target word when native speakers of Japanese learn to translate English words into Japanese. Pairs of English words contrasted in several phonemic distinctions (e.g., /r/-/l/, /b/-/v/, etc.) were used as word materials, and presented in three conditions; visual-only (V), audio-only (A), and audio-visual (AV) presentations. Identification accuracy of those words produced by two talkers was also assessed. During pretest, the accuracy for A stimuli was lowest, implying that insufficient translation ability and listening ability interact with each other when aurally presented word has to be translated. However, there was no difference in accuracy between V and AV stimuli, suggesting that participants translate the words depending on visual information only. The effect of translation training using AV stimuli did not transfer to identification ability, showing that additional audio information during translation does not help improve speech perception. Further examination is necessary to determine the effective L2 training method. [Work supported by TAO, Japan.

  15. NESP: Nonlinear enhancement and selection of plane for optimal segmentation and recognition of scene word images

    NASA Astrophysics Data System (ADS)

    Kumar, Deepak; Anil Prasad, M. N.; Ramakrishnan, A. G.

    2013-01-01

    In this paper, we report a breakthrough result on the difficult task of segmentation and recognition of coloured text from the word image dataset of ICDAR robust reading competition challenge 2: reading text in scene images. We split the word image into individual colour, gray and lightness planes and enhance the contrast of each of these planes independently by a power-law transform. The discrimination factor of each plane is computed as the maximum between-class variance used in Otsu thresholding. The plane that has maximum discrimination factor is selected for segmentation. The trial version of Omnipage OCR is then used on the binarized words for recognition. Our recognition results on ICDAR 2011 and ICDAR 2003 word datasets are compared with those reported in the literature. As baseline, the images binarized by simple global and local thresholding techniques were also recognized. The word recognition rate obtained by our non-linear enhancement and selection of plance method is 72.8% and 66.2% for ICDAR 2011 and 2003 word datasets, respectively. We have created ground-truth for each image at the pixel level to benchmark these datasets using a toolkit developed by us. The recognition rate of benchmarked images is 86.7% and 83.9% for ICDAR 2011 and 2003 datasets, respectively.

  16. A Novel Word Based Arabic Handwritten Recognition System Using SVM Classifier

    NASA Astrophysics Data System (ADS)

    Khalifa, Mahmoud; Bingru, Yang

    Every language script has its structure, characteristic, and feature. Character based word recognition depends on the feature available to be extracted from character. Word based script recognition overcome the problem of character segmenting and can be applied for several languages (Arabic, Urdu, Farsi... est.). In this paper Arabic handwritten is classified as word based system. Firstly, words segmented and normalized in size to fit the DCT input. Then extract feature characteristic by computing the Euclidean distance between pairs of objects in n-by-m data matrix X. Based on the point's operator of extrema, feature was extracted. Then apply one to one-Class Support Vector Machines (SVMs) as a discriminative framework in order to address feature classification. The approach was tested with several public databases and we get high efficiency rate recognition.

  17. Effects of age and hearing loss on recognition of unaccented and accented multisyllabic words.

    PubMed

    Gordon-Salant, Sandra; Yeni-Komshian, Grace H; Fitzgibbons, Peter J; Cohen, Julie I

    2015-02-01

    The effects of age and hearing loss on recognition of unaccented and accented words of varying syllable length were investigated. It was hypothesized that with increments in length of syllables, there would be atypical alterations in syllable stress in accented compared to native English, and that these altered stress patterns would be sensitive to auditory temporal processing deficits with aging. Sets of one-, two-, three-, and four-syllable words with the same initial syllable were recorded by one native English and two Spanish-accented talkers. Lists of these words were presented in isolation and in sentence contexts to younger and older normal-hearing listeners and to older hearing-impaired listeners. Hearing loss effects were apparent for unaccented and accented monosyllabic words, whereas age effects were observed for recognition of accented multisyllabic words, consistent with the notion that altered syllable stress patterns with accent are sensitive for revealing effects of age. Older listeners also exhibited lower recognition scores for moderately accented words in sentence contexts than in isolation, suggesting that the added demands on working memory for words in sentence contexts impact recognition of accented speech. The general pattern of results suggests that hearing loss, age, and cognitive factors limit the ability to recognize Spanish-accented speech.

  18. Effects of age and hearing loss on recognition of unaccented and accented multisyllabic words

    PubMed Central

    Gordon-Salant, Sandra; Yeni-Komshian, Grace H.; Fitzgibbons, Peter J.; Cohen, Julie I.

    2015-01-01

    The effects of age and hearing loss on recognition of unaccented and accented words of varying syllable length were investigated. It was hypothesized that with increments in length of syllables, there would be atypical alterations in syllable stress in accented compared to native English, and that these altered stress patterns would be sensitive to auditory temporal processing deficits with aging. Sets of one-, two-, three-, and four-syllable words with the same initial syllable were recorded by one native English and two Spanish-accented talkers. Lists of these words were presented in isolation and in sentence contexts to younger and older normal-hearing listeners and to older hearing-impaired listeners. Hearing loss effects were apparent for unaccented and accented monosyllabic words, whereas age effects were observed for recognition of accented multisyllabic words, consistent with the notion that altered syllable stress patterns with accent are sensitive for revealing effects of age. Older listeners also exhibited lower recognition scores for moderately accented words in sentence contexts than in isolation, suggesting that the added demands on working memory for words in sentence contexts impact recognition of accented speech. The general pattern of results suggests that hearing loss, age, and cognitive factors limit the ability to recognize Spanish-accented speech. PMID:25698021

  19. Evaluating a split processing model of visual word recognition: effects of orthographic neighborhood size.

    PubMed

    Lavidor, Michal; Hayes, Adrian; Shillcock, Richard; Ellis, Andrew W

    2004-03-01

    The split fovea theory proposes that visual word recognition of centrally presented words is mediated by the splitting of the foveal image, with letters to the left of fixation being projected to the right hemisphere (RH) and letters to the right of fixation being projected to the left hemisphere (LH). Two lexical decision experiments aimed to elucidate word recognition processes under the split fovea theory are described. The first experiment showed that when words were presented centrally, such that the initial letters were in the left visual field (LVF/RH), there were effects of orthographic neighborhood, i.e., there were faster responses to words with high rather than low orthographic neighborhoods for the initial letters ('lead neighbors'). This effect was limited to lead-neighbors but not end-neighbors (orthographic neighbors sharing the same final letters). When the same words were fully presented in the LVF/RH or right visual field (RVF/LH, Experiment 2), there was no effect of orthographic neighborhood size. We argue that the lack of an effect in Experiment 2 was due to exposure to all of the letters of the words, the words being matched for overall orthographic neighborhood count and the sub-parts no longer having a unique effect. We concluded that the orthographic activation found in Experiment 1 occurred because the initial letters of centrally presented words were projected to the RH. The results support the split fovea theory, where the RH has primacy in representing lead neighbors of a written word.

  20. Neighborhood Density and Word Recognition: Effects of Phoneme Position

    ERIC Educational Resources Information Center

    Prescott, Tiffany Joyce Conyers

    2009-01-01

    There is considerable interest in how individuals process single words when they are heard. An examination of the literature reveals an interesting, yet little-explored contradiction between the assumptions underlying the neighborhood activation model (NAM) and contemporary models of word retrieval. In this study, participants listened to CVC…

  1. Context affects L1 but not L2 during bilingual word recognition: an MEG study.

    PubMed

    Pellikka, Janne; Helenius, Päivi; Mäkelä, Jyrki P; Lehtonen, Minna

    2015-03-01

    How do bilinguals manage the activation levels of the two languages and prevent interference from the irrelevant language? Using magnetoencephalography, we studied the effect of context on the activation levels of languages by manipulating the composition of word lists (the probability of the languages) presented auditorily to late Finnish-English bilinguals. We first determined the upper limit time-window for semantic access, and then focused on the preceding responses during which the actual word recognition processes were assumedly ongoing. Between 300 and 500 ms in the temporal cortices (in the N400 m response) we found an asymmetric language switching effect: the responses to L1 Finnish words were affected by the presentation context unlike the responses to L2 English words. This finding suggests that the stronger language is suppressed in an L2 context, supporting models that allow auditory word recognition to be affected by contextual factors and the language system to be subject to inhibitory influence.

  2. Distinguishing Target From Distractor in Stroop, Picture-Word, and Word-Word Interference Tasks.

    PubMed

    Schmalz, Xenia; Treccani, Barbara; Mulatti, Claudio

    2015-01-01

    Lexical selection-both during reading aloud and speech production-involves selecting an intended word, while ignoring irrelevant lexical activation. This process has been studied by the use of interference tasks. Examples are the Stroop task, where participants ignore the written color word and name the color of the ink, picture-word interference tasks, where participants name a picture while ignoring a super-imposed written word, or word-word interference (WWI) tasks, where two words are presented and the participants need to respond to only one, based on an pre-determined visual feature (e.g., color, position). Here, we focus on the WWI task: it is theoretically impossible for existing models to explain how the cognitive system can respond to one stimulus and block the other, when they are presented by the same modality (i.e., they are both words). We describe a solution that can explain performance on the WWI task: drawing on the literature on visual attention, we propose that the system creates an object file for each perceived object, which is continuously updated with increasingly complete information about the stimulus, such as the task-relevant visual feature. Such a model can account for performance on all three tasks. PMID:26696927

  3. Evidence for the Activation of Sensorimotor Information during Visual Word Recognition: The Body-Object Interaction Effect

    ERIC Educational Resources Information Center

    Siakaluk, Paul D.; Pexman, Penny M.; Aguilera, Laura; Owen, William J.; Sears, Christopher R.

    2008-01-01

    We examined the effects of sensorimotor experience in two visual word recognition tasks. Body-object interaction (BOI) ratings were collected for a large set of words. These ratings assess perceptions of the ease with which a human body can physically interact with a word's referent. A set of high BOI words (e.g., "mask") and a set of low BOI…

  4. Individual differences in visual word recognition: insights from the English Lexicon Project.

    PubMed

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

    2012-02-01

    Empirical work and models of visual word recognition have traditionally focused on group-level performance. Despite the emphasis on the prototypical reader, there is clear evidence that variation in reading skill modulates word recognition performance. In the present study, we examined differences among individuals who contributed to the English Lexicon Project (http://elexicon.wustl.edu), an online behavioral database containing nearly 4 million word recognition (speeded pronunciation and lexical decision) trials from over 1,200 participants. We observed considerable within- and between-session reliability across distinct sets of items, in terms of overall mean response time (RT), RT distributional characteristics, diffusion model parameters (Ratcliff, Gomez, & McKoon, 2004), and sensitivity to underlying lexical dimensions. This indicates reliably detectable individual differences in word recognition performance. In addition, higher vocabulary knowledge was associated with faster, more accurate word recognition performance, attenuated sensitivity to stimuli characteristics, and more efficient accumulation of information. Finally, in contrast to suggestions in the literature, we did not find evidence that individuals were trading-off their utilization of lexical and nonlexical information. PMID:21728459

  5. Face recognition system and method using face pattern words and face pattern bytes

    SciTech Connect

    Zheng, Yufeng

    2014-12-23

    The present invention provides a novel system and method for identifying individuals and for face recognition utilizing facial features for face identification. The system and method of the invention comprise creating facial features or face patterns called face pattern words and face pattern bytes for face identification. The invention also provides for pattern recognitions for identification other than face recognition. The invention further provides a means for identifying individuals based on visible and/or thermal images of those individuals by utilizing computer software implemented by instructions on a computer or computer system and a computer readable medium containing instructions on a computer system for face recognition and identification.

  6. Random Word Recognition Chart Helps Scotoma Assessment in Low Vision

    PubMed Central

    MacKeben, Manfred; Nair, Unni K.W.; Walker, Laura L.; Fletcher, Donald C.

    2015-01-01

    ABSTRACT Purpose To evaluate the use of SKread, a vision test based on random word sequences that prevents the prediction of upcoming words by linguistic criteria and is simple to score in a clinical setting. Methods SKread combines the standardized format of the MNread test with sequences of random words and letters like the Pepper Visual Skills for Reading test. A total of 231 subjects (aged 16 to 97 years) participated. We report data from 136 eyes of subjects with a maculopathy and 65 with normal or near-normal vision. Test reliability was investigated on an additional 30 eye-healthy subjects. We tested visual acuity and reading performance for continuous text and random words monocularly. Reading speed and all errors made are reported. Results Reading speed was always higher for continuous text than for random word sequences, even in normally sighted subjects for whom the median reading times per paragraph were 2.4 s (MNread) vs. 6.8 s (SKread). In patients with maculopathies, the medians were 4.2 s vs. 12.25 s. These differences were statistically significant. Number and type of errors made depended only negligibly on age and visual acuity. Patients with a dense scotoma right of fixation made more “right errors” by missing letters at the end of words, whereas those with a scotoma left of fixation made more “left errors” by missing letters at the beginning of words. The SKread test showed good test-retest repeatability. Conclusions The unpredictability of random word and letter sequences renders reading performance highly dependent on eyesight and less dependent on reading skill and educational level. Recurrent right or left errors can indicate the presence and location of a scotoma without expensive equipment. This knowledge can be used to teach patients about how the scotoma can interfere with their vision. PMID:25946100

  7. Sizing up the competition: quantifying the influence of the mental lexicon on auditory and visual spoken word recognition.

    PubMed

    Strand, Julia F; Sommers, Mitchell S

    2011-09-01

    Much research has explored how spoken word recognition is influenced by the architecture and dynamics of the mental lexicon (e.g., Luce and Pisoni, 1998; McClelland and Elman, 1986). A more recent question is whether the processes underlying word recognition are unique to the auditory domain, or whether visually perceived (lipread) speech may also be sensitive to the structure of the mental lexicon (Auer, 2002; Mattys, Bernstein, and Auer, 2002). The current research was designed to test the hypothesis that both aurally and visually perceived spoken words are isolated in the mental lexicon as a function of their modality-specific perceptual similarity to other words. Lexical competition (the extent to which perceptually similar words influence recognition of a stimulus word) was quantified using metrics that are well-established in the literature, as well as a statistical method for calculating perceptual confusability based on the phi-square statistic. Both auditory and visual spoken word recognition were influenced by modality-specific lexical competition as well as stimulus word frequency. These findings extend the scope of activation-competition models of spoken word recognition and reinforce the hypothesis (Auer, 2002; Mattys et al., 2002) that perceptual and cognitive properties underlying spoken word recognition are not specific to the auditory domain. In addition, the results support the use of the phi-square statistic as a better predictor of lexical competition than metrics currently used in models of spoken word recognition.

  8. Feature activation during word recognition: action, visual, and associative-semantic priming effects

    PubMed Central

    Lam, Kevin J. Y.; Dijkstra, Ton; Rueschemeyer, Shirley-Ann

    2015-01-01

    Embodied theories of language postulate that language meaning is stored in modality-specific brain areas generally involved in perception and action in the real world. However, the temporal dynamics of the interaction between modality-specific information and lexical-semantic processing remain unclear. We investigated the relative timing at which two types of modality-specific information (action-based and visual-form information) contribute to lexical-semantic comprehension. To this end, we applied a behavioral priming paradigm in which prime and target words were related with respect to (1) action features, (2) visual features, or (3) semantically associative information. Using a Go/No-Go lexical decision task, priming effects were measured across four different inter-stimulus intervals (ISI = 100, 250, 400, and 1000 ms) to determine the relative time course of the different features. Notably, action priming effects were found in ISIs of 100, 250, and 1000 ms whereas a visual priming effect was seen only in the ISI of 1000 ms. Importantly, our data suggest that features follow different time courses of activation during word recognition. In this regard, feature activation is dynamic, measurable in specific time windows but not in others. Thus the current study (1) demonstrates how multiple ISIs can be used within an experiment to help chart the time course of feature activation and (2) provides new evidence for embodied theories of language. PMID:26074836

  9. THE INFLUENCE OF SYLLABIFICATION RULES IN L1 ON L2 WORD RECOGNITION.

    PubMed

    Choi, Wonil; Nam, Kichun; Lee, Yoonhyoung

    2015-10-01

    Experiments with Korean learners of English and English monolinguals were conducted to examine whether knowledge of syllabification in the native language (Korean) affects the recognition of printed words in the non-native language (English). Another purpose of this study was to test whether syllables are the processing unit in Korean visual word recognition. In Experiment 1, 26 native Korean speakers and 19 native English speakers participated. In Experiment 2, 40 native Korean speakers participated. In two experiments, syllable length was manipulated based on the Korean syllabification rule and the participants performed a lexical decision task. Analyses of variance were performed for the lexical decision latencies and error rates in two experiments. The results from Korean learners of English showed that two-syllable words based on the Korean syllabification rule were recognized faster as words than various types of three-syllable words, suggesting that Korean learners of English exploited their L1 phonological knowledge in recognizing English words. The results of the current study also support the idea that syllables are a processing unit of Korean visual word recognition.

  10. The effects of case mixing on word recognition: evidence from a PET study.

    PubMed

    Mayall, K; Humphreys, G W; Mechelli, A; Olson, A; Price, C J

    2001-08-15

    The early stages of visual word recognition were investigated by scanning participants using PET as they took part in implicit and explicit reading tasks with visually disrupted stimuli. CaSe MiXiNg has been shown in behavioral studies to increase reaction times (RTs) in naming and other word recognition tasks. In this study, we found that during both an implicit (feature detection) task and an explicit word-naming task, mixed-case words compared to same-case words produced increased activation in an area of the right parietal cortex previously associated with visual attention. No effect of case was found in this area for pseudowords or consonant strings. Further, lowering the contrast of the stimuli slowed RTs as much as case mixing, but did not lead to the same increase in right parietal activation. No significant effect of case mixing was observed in left-hemisphere language areas. The results suggest that reading mixed-case words requires increased attentional processing. However, later word recognition processes may be relatively unaffected by the disruption in presentation.

  11. Memory bias for negative emotional words in recognition memory is driven by effects of category membership.

    PubMed

    White, Corey N; Kapucu, Aycan; Bruno, Davide; Rotello, Caren M; Ratcliff, Roger

    2014-01-01

    Recognition memory studies often find that emotional items are more likely than neutral items to be labelled as studied. Previous work suggests this bias is driven by increased memory strength/familiarity for emotional items. We explored strength and bias interpretations of this effect with the conjecture that emotional stimuli might seem more familiar because they share features with studied items from the same category. Categorical effects were manipulated in a recognition task by presenting lists with a small, medium or large proportion of emotional words. The liberal memory bias for emotional words was only observed when a medium or large proportion of categorised words were presented in the lists. Similar, though weaker, effects were observed with categorised words that were not emotional (animal names). These results suggest that liberal memory bias for emotional items may be largely driven by effects of category membership.

  12. Memory bias for negative emotional words in recognition memory is driven by effects of category membership

    PubMed Central

    White, Corey N.; Kapucu, Aycan; Bruno, Davide; Rotello, Caren M.; Ratcliff, Roger

    2014-01-01

    Recognition memory studies often find that emotional items are more likely than neutral items to be labeled as studied. Previous work suggests this bias is driven by increased memory strength/familiarity for emotional items. We explored strength and bias interpretations of this effect with the conjecture that emotional stimuli might seem more familiar because they share features with studied items from the same category. Categorical effects were manipulated in a recognition task by presenting lists with a small, medium, or large proportion of emotional words. The liberal memory bias for emotional words was only observed when a medium or large proportion of categorized words were presented in the lists. Similar, though weaker, effects were observed with categorized words that were not emotional (animal names). These results suggest that liberal memory bias for emotional items may be largely driven by effects of category membership. PMID:24303902

  13. Target Recognition Using Neural Networks for Model Deformation Measurements

    NASA Technical Reports Server (NTRS)

    Ross, Richard W.; Hibler, David L.

    1999-01-01

    Optical measurements provide a non-invasive method for measuring deformation of wind tunnel models. Model deformation systems use targets mounted or painted on the surface of the model to identify known positions, and photogrammetric methods are used to calculate 3-D positions of the targets on the model from digital 2-D images. Under ideal conditions, the reflective targets are placed against a dark background and provide high-contrast images, aiding in target recognition. However, glints of light reflecting from the model surface, or reduced contrast caused by light source or model smoothness constraints, can compromise accurate target determination using current algorithmic methods. This paper describes a technique using a neural network and image processing technologies which increases the reliability of target recognition systems. Unlike algorithmic methods, the neural network can be trained to identify the characteristic patterns that distinguish targets from other objects of similar size and appearance and can adapt to changes in lighting and environmental conditions.

  14. Radar target recognition using non-cooperative scatterer matching game

    NASA Astrophysics Data System (ADS)

    Jouny, Ismail

    2012-05-01

    This paper utilizes game-theoretic principles in the automatic recognition of unknown radar targets. This study uses a non-cooperative matching game where pure strategies are associated with specific items to be matched, and agreement between possible hypotheses represents the payoff gained when playing a certain strategy against an opponent who is playing another strategy. The target recognition approach attempts to match scattering centers of an unknown target with those of library targets as competing strategies. The algorithm is tested using real radar data representing scattering from commercial aircraft models. Radar data of library targets at various azimuth positions are matched against an unknown radar target signature at a specific aspect angle. Computer simulations provide an estimate of the error rates in scenarios of additive Gaussian noise corrupting target signatures.

  15. Reading component skills in dyslexia: word recognition, comprehension and processing speed.

    PubMed

    de Oliveira, Darlene G; da Silva, Patrícia B; Dias, Natália M; Seabra, Alessandra G; Macedo, Elizeu C

    2014-01-01

    The cognitive model of reading comprehension (RC) posits that RC 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 RC 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 RC, word recognition, processing speed, picture naming, receptive vocabulary, and phonological awareness were assessed. There were no group differences regarding the accuracy in oral and RC, 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 RC 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.

  16. Influences of Lexical Tone and Pitch on Word Recognition in Bilingual Infants

    PubMed Central

    Singh, Leher; Foong, Joanne

    2012-01-01

    Infants’ abilities to discriminate native and non-native phonemes have been extensively investigated in monolingual learners, demonstrating a transition from language-general to language-specific sensitivities over the first year after birth. However, these studies have mostly been limited to the study of vowels and consonants in monolingual learners. There is relatively little research on other types of phonetic segments, such as lexical tone, even though tone languages are very well represented across languages of the world. The goal of the present study is to investigate how Mandarin Chinese-English bilingual learners contend with non-phonemic pitch variation in English spoken word recognition. This is contrasted with their treatment of phonemic changes in lexical tone in Mandarin spoken word recognition. The experimental design was cross-sectional and three age-groups were sampled (7.5 months, 9 months and 11 months). Results demonstrated limited generalization abilities at 7.5 months, where infants only recognized words in English when matched in pitch and words in Mandarin that were matched in tone. At 9 months, infants recognized words in Mandarin Chinese that matched in tone, but also falsely recognized words that contrasted in tone. At this age, infants also recognized English words whether they were matched or mismatched in pitch. By 11 months, infants correctly recognized pitch-matched and - mismatched words in English but only recognized tonal matches in Mandarin Chinese. PMID:22682766

  17. Reassessing word frequency as a determinant of word recognition for skilled and unskilled readers

    PubMed Central

    Kuperman, Victor; Van Dyke, Julie A.

    2013-01-01

    The importance of vocabulary in reading comprehension emphasizes the need to accurately assess an individual’s familiarity with words. The present article highlights problems with using occurrence counts in corpora as an index of word familiarity, especially when studying individuals varying in reading experience. We demonstrate via computational simulations and norming studies that corpus-based word frequencies systematically overestimate strengths of word representations, especially in the low-frequency range and in smaller-size vocabularies. Experience-driven differences in word familiarity prove to be faithfully captured by the subjective frequency ratings collected from responders at different experience levels. When matched on those levels, this lexical measure explains more variance than corpus-based frequencies in eye-movement and lexical decision latencies to English words, attested in populations with varied reading experience and skill. Furthermore, the use of subjective frequencies removes the widely reported (corpus) frequency-by-skill interaction, showing that more skilled readers are equally faster in processing any word than the less skilled readers, not disproportionally faster in processing lower-frequency words. This finding challenges the view that the more skilled an individual is in generic mechanisms of word processing the less reliant he/she will be on the actual lexical characteristics of that word. PMID:23339352

  18. The resolution of visual noise in word recognition.

    PubMed

    Pae, Hye K; Lee, Yong-Won

    2015-06-01

    This study examined lexical processing in English by native speakers of Korean and Chinese, compared to that of native speakers of English, using normal, alternated, and inverse fonts. Sixty four adult students participated in a lexical decision task. The findings demonstrated similarities and differences in accuracy and latency among the three L1 groups. The participants, regardless of L1, had a greater advantage in nonwords than words for the normal fonts because they were able to efficiently detect the illegal letter strings. However, word advantages were observed in the visually distorted stimuli (i.e., alternated and inverse fonts). These results were explained from the perspectives of the theory of psycholinguistic grain size, L1-L2 distance, and the mechanism of familiarity discrimination. The native speakers of Chinese were more sensitive to visual distortions than the Korean counterpart, suggesting that the linguistic template established in L1 might play a role in word processing in English.

  19. The resolution of visual noise in word recognition.

    PubMed

    Pae, Hye K; Lee, Yong-Won

    2015-06-01

    This study examined lexical processing in English by native speakers of Korean and Chinese, compared to that of native speakers of English, using normal, alternated, and inverse fonts. Sixty four adult students participated in a lexical decision task. The findings demonstrated similarities and differences in accuracy and latency among the three L1 groups. The participants, regardless of L1, had a greater advantage in nonwords than words for the normal fonts because they were able to efficiently detect the illegal letter strings. However, word advantages were observed in the visually distorted stimuli (i.e., alternated and inverse fonts). These results were explained from the perspectives of the theory of psycholinguistic grain size, L1-L2 distance, and the mechanism of familiarity discrimination. The native speakers of Chinese were more sensitive to visual distortions than the Korean counterpart, suggesting that the linguistic template established in L1 might play a role in word processing in English. PMID:25283377

  20. Assessing spoken word recognition in children who are deaf or hard of hearing: a translational approach.

    PubMed

    Kirk, Karen Iler; Prusick, Lindsay; French, Brian; Gotch, Chad; Eisenberg, Laurie S; Young, Nancy

    2012-06-01

    Under natural conditions, listeners use both auditory and visual speech cues to extract meaning from speech signals containing many sources of variability. However, traditional clinical tests of spoken word recognition routinely employ isolated words or sentences produced by a single talker in an auditory-only presentation format. The more central cognitive processes used during multimodal integration, perceptual normalization, and lexical discrimination that may contribute to individual variation in spoken word recognition performance are not assessed in conventional tests of this kind. In this article, we review our past and current research activities aimed at developing a series of new assessment tools designed to evaluate spoken word recognition in children who are deaf or hard of hearing. These measures are theoretically motivated by a current model of spoken word recognition and also incorporate "real-world" stimulus variability in the form of multiple talkers and presentation formats. The goal of this research is to enhance our ability to estimate real-world listening skills and to predict benefit from sensory aid use in children with varying degrees of hearing loss. PMID:22668766

  1. Semantic Richness Effects in Spoken Word Recognition: A Lexical Decision and Semantic Categorization Megastudy

    PubMed Central

    Goh, Winston D.; Yap, Melvin J.; Lau, Mabel C.; Ng, Melvin M. R.; Tan, Luuan-Chin

    2016-01-01

    A large number of studies have demonstrated that semantic richness dimensions [e.g., number of features, semantic neighborhood density, semantic diversity , concreteness, emotional valence] influence word recognition processes. Some of these richness effects appear to be task-general, while others have been found to vary across tasks. Importantly, almost all of these findings have been found in the visual word recognition literature. To address this gap, we examined the extent to which these semantic richness effects are also found in spoken word recognition, using a megastudy approach that allows for an examination of the relative contribution of the various semantic properties to performance in two tasks: lexical decision, and semantic categorization. The results show that concreteness, valence, and number of features accounted for unique variance in latencies across both tasks in a similar direction—faster responses for spoken words that were concrete, emotionally valenced, and with a high number of features—while arousal, semantic neighborhood density, and semantic diversity did not influence latencies. Implications for spoken word recognition processes are discussed. PMID:27445936

  2. Semantic Richness Effects in Spoken Word Recognition: A Lexical Decision and Semantic Categorization Megastudy.

    PubMed

    Goh, Winston D; Yap, Melvin J; Lau, Mabel C; Ng, Melvin M R; Tan, Luuan-Chin

    2016-01-01

    A large number of studies have demonstrated that semantic richness dimensions [e.g., number of features, semantic neighborhood density, semantic diversity , concreteness, emotional valence] influence word recognition processes. Some of these richness effects appear to be task-general, while others have been found to vary across tasks. Importantly, almost all of these findings have been found in the visual word recognition literature. To address this gap, we examined the extent to which these semantic richness effects are also found in spoken word recognition, using a megastudy approach that allows for an examination of the relative contribution of the various semantic properties to performance in two tasks: lexical decision, and semantic categorization. The results show that concreteness, valence, and number of features accounted for unique variance in latencies across both tasks in a similar direction-faster responses for spoken words that were concrete, emotionally valenced, and with a high number of features-while arousal, semantic neighborhood density, and semantic diversity did not influence latencies. Implications for spoken word recognition processes are discussed. PMID:27445936

  3. Case-mixing effects on children's word recognition: lexical feedback and development.

    PubMed

    Mayall, Kate

    2002-04-01

    Presenting words in MiXeD cAsE has previously been shown to disrupt naming performance of adult readers. This effect is greater on nonwords than it is on real words. There have been two main accounts of this interaction. First, case mixing may disrupt naming via non-lexical spelling-to-sound correspondences to a greater extent than it disrupts lexical naming. Alternatively, stored lexical knowledge of words may feed back to a visual analysis level during processing of a visually presented word, helping known words to overcome the visual disruption caused by case mixing. In the present study, when young children (aged 6 and 8 years) were tested, case mixing did not disrupt nonword naming more than word naming. However, slightly older children (aged 9 years) demonstrated the same pattern of performance as adults. These results support the view that top-down lexical information can aid overcoming visual disruption to words, and that beginning readers have not developed the stored word knowledge necessary to allow this. In addition, a greater case-mixing effect on high-frequency words for the youngest age group (6-year-olds) suggests that their word recognition may be based more on wholistic visual features than is that of older children.

  4. Vowel Categorization during Word Recognition in Bilingual Toddlers

    ERIC Educational Resources Information Center

    Ramon-Casas, Marta; Swingley, Daniel; Sebastian-Galles, Nuria; Bosch, Laura

    2009-01-01

    Toddlers' and preschoolers' knowledge of the phonological forms of words was tested in Spanish-learning, Catalan-learning, and bilingual children. These populations are of particular interest because of differences in the Spanish and Catalan vowel systems: Catalan has two vowels in a phonetic region where Spanish has only one. The proximity of the…

  5. Word Learning under Adverse Listening Conditions: Context-Specific Recognition

    ERIC Educational Resources Information Center

    Creel, Sarah C.; Aslin, Richard N.; Tanenhaus, Michael K.

    2012-01-01

    Previous studies of word learning have presented the items to listeners under ideal conditions. Here we ask how listeners learn new vocabulary items under adverse listening conditions. Would listeners form acoustically-specific representations that incorporated the noise, base their representations on noise-free language knowledge, or both? To…

  6. Parallel algorithm for target recognition using a multiclass hash database

    NASA Astrophysics Data System (ADS)

    Uddin, Mosleh; Myler, Harley R.

    1998-07-01

    A method for recognition of unknown targets using large databases of model targets is discussed. Our approach is based on parallel processing of multi-class hash databases that are generated off-line. A geometric hashing technique is used on feature points of model targets to create each class database. Bit level coding is then performed to represent the models in an image format. Parallelism is achieved during the recognition phase. Feature points of an unknown target are passed to parallel processors each accessing an individual class database. Each processor reads a particular class of hash data base and indexes feature points of the unknown target. A simple voting technique is applied to determine the best match model with the unknown. The paper discusses our technique and the results from testing with unknown FLIR targets.

  7. Does training on a phonemic contrast absent in the listener's dialect influence word recognition?

    PubMed

    Dufour, Sophie; Nguyen, Noël; Frauenfelder, Ulrich Hans

    2010-07-01

    Southern French listeners were trained on the word final Standard French /e/-/epsilon/ contrast that does not exist in their dialect. They learned to associate minimal pairs of new words with visual shapes. Although final training session performance was relatively high, the learning did not transfer to a lexical decision task with phonological priming. Thus successful training on a phonemic contrast did not guarantee the efficient use of this contrast in spoken word recognition tasks. These findings are discussed in light of abstractionist and exemplarist models.

  8. Spoken Idiom Recognition: Meaning Retrieval and Word Expectancy

    ERIC Educational Resources Information Center

    Tabossi, Patrizia; Fanari, Rachele; Wolf, Kinou

    2005-01-01

    This study investigates recognition of spoken idioms occurring in neutral contexts. Experiment 1 showed that both predictable and non-predictable idiom meanings are available at string offset. Yet, only predictable idiom meanings are active halfway through a string and remain active after the string's literal conclusion. Experiment 2 showed that…

  9. Lexical Representation of Phonological Variation in Spoken Word Recognition

    ERIC Educational Resources Information Center

    Ranbom, Larissa J.; Connine, Cynthia M.

    2007-01-01

    There have been a number of mechanisms proposed to account for recognition of phonological variation in spoken language. Five of these mechanisms were considered here, including underspecification, inference, feature parsing, tolerance, and a frequency-based representational account. A corpus analysis and five experiments using the nasal flap…

  10. Reassessing Word Frequency as a Determinant of Word Recognition for Skilled and Unskilled Readers

    ERIC Educational Resources Information Center

    Kuperman, Victor; Van Dyke, Julie A.

    2013-01-01

    The importance of vocabulary in reading comprehension emphasizes the need to accurately assess an individual's familiarity with words. The present article highlights problems with using occurrence counts in corpora as an index of word familiarity, especially when studying individuals varying in reading experience. We demonstrate via computational…

  11. The Neural Basis of Competition in Auditory Word Recognition and Spoken Word Production

    ERIC Educational Resources Information Center

    Righi, Giulia

    2010-01-01

    The goal of this dissertation is to examine how brain regions respond to different types of competition during word comprehension and word production. I will present three studies that attempt to enhance the current understanding of which brain regions are sensitive to different aspects of competition and how the nature of the stimuli and the…

  12. A magnetic stimulation examination of orthographic neighborhood effects in visual word recognition.

    PubMed

    Lavidor, Michal; Walsh, Vincent

    2003-04-01

    The split-fovea theory proposes that visual word recognition is mediated by the splitting of the foveal image, with letters to the left of fixation projected to the right hemisphere (RH) and letters to the right of fixation projected to the left hemisphere (LH). We applied repetitive transcranial magnetic stimulation (rTMS) over the left and right occipital cortex during a lexical decision task to investigate the extent to which word recognition processes could be accounted for according to the split-fovea theory. Unilateral rTMS significantly impaired lexical decision latencies to centrally presented words, supporting the suggestion that foveal representation of words is split between the cerebral hemispheres rather than bilateral. Behaviorally, we showed that words that have many orthographic neighbors sharing the same initial letters ("lead neighbors") facilitated lexical decision more than words with few lead neighbors. This effect did not apply to end neighbors (orthographic neighbors sharing the same final letters). Crucially, rTMS over the RH impaired lead-, but not end-neighborhood facilitation. The results support the split-fovea theory, where the RH has primacy in representing lead neighbors of a written word.

  13. An ERP investigation of the co-development of hemispheric lateralization of face and word recognition.

    PubMed

    Dundas, Eva M; Plaut, David C; Behrmann, Marlene

    2014-08-01

    The adult human brain would appear to have specialized and independent neural systems for the visual processing of words and faces. Extensive evidence has demonstrated greater selectivity for written words in the left over right hemisphere, and, conversely, greater selectivity for faces in the right over left hemisphere. This study examines the emergence of these complementary neural profiles, as well as the possible relationship between them. Using behavioral and neurophysiological measures, in adults, we observed the standard finding of greater accuracy and a larger N170 ERP component in the left over right hemisphere for words, and conversely, greater accuracy and a larger N170 in the right over the left hemisphere for faces. We also found that although children aged 7-12 years revealed the adult hemispheric pattern for words, they showed neither a behavioral nor a neural hemispheric superiority for faces. Of particular interest, the magnitude of their N170 for faces in the right hemisphere was related to that of the N170 for words in their left hemisphere. These findings suggest that the hemispheric organization of face recognition and of word recognition does not develop independently, and that word lateralization may precede and drive later face lateralization. A theoretical account for the findings, in which competition for visual representations unfolds over the course of development, is discussed.

  14. An ERP investigation of the co-development of hemispheric lateralization of face and word recognition

    PubMed Central

    Dundas, Eva M.; Plaut, David C.; Behrmann, Marlene

    2014-01-01

    The adult human brain would appear to have specialized and independent neural systems for the visual processing of words and faces. Extensive evidence has demonstrated greater selectivity for written words in the left over right hemisphere, and, conversely, greater selectivity for faces in the right over left hemisphere. This study examines the emergence of these complementary neural profiles, as well as the possible relationship between them. Using behavioral and neurophysiological measures, in adults, we observed the standard finding of greater accuracy and a larger N170 ERP component in the left over right hemisphere for words, and conversely, greater accuracy and a larger N170 in the right over the left hemisphere for faces. We also found that, although children aged 7-12 years revealed the adult hemispheric pattern for words, they showed neither a behavioral nor a neural hemispheric superiority for faces. Of particular interest, the magnitude of their N170 for faces in the right hemisphere was related to that of the N170 for words in their left hemisphere. These findings suggest that the hemispheric organization of face recognition and of word recognition do not develop independently, and that word lateralization may precede and drive later face lateralization. A theoretical account for the findings, in which competition for visual representations unfolds over the course of development, is discussed. PMID:24933662

  15. Functions of graphemic and phonemic codes in visual word-recognition.

    PubMed

    Meyer, D E; Schvaneveldt, R W; Ruddy, M G

    1974-03-01

    Previous investigators have argued that printed words are recognized directly from visual representations and/or phonological representations obtained through phonemic recoding. The present research tested these hypotheses by manipulating graphemic and phonemic relations within various pairs of letter strings. Ss in two experiments classified the pairs as words or nonwords. Reaction times and error rates were relatively small for word pairs (e.g., BRIBE-TRIBE) that were both graphemically, and phonemically similar. Graphemic similarity alone inhibited performance on other word pairs (e.g., COUCH-TOUCH). These and other results suggest that phonological representations play a significant role in visual word recognition and that there is a dependence between successive phonemic-encoding operations. An encoding-bias model is proposed to explain the data. PMID:24214761

  16. Composite Wavelet Filters for Enhanced Automated Target Recognition

    NASA Technical Reports Server (NTRS)

    Chiang, Jeffrey N.; Zhang, Yuhan; Lu, Thomas T.; Chao, Tien-Hsin

    2012-01-01

    Automated Target Recognition (ATR) systems aim to automate target detection, recognition, and tracking. The current project applies a JPL ATR system to low-resolution sonar and camera videos taken from unmanned vehicles. These sonar images are inherently noisy and difficult to interpret, and pictures taken underwater are unreliable due to murkiness and inconsistent lighting. The ATR system breaks target recognition into three stages: 1) Videos of both sonar and camera footage are broken into frames and preprocessed to enhance images and detect Regions of Interest (ROIs). 2) Features are extracted from these ROIs in preparation for classification. 3) ROIs are classified as true or false positives using a standard Neural Network based on the extracted features. Several preprocessing, feature extraction, and training methods are tested and discussed in this paper.

  17. Composite wavelet filters for enhanced automated target recognition

    NASA Astrophysics Data System (ADS)

    Chiang, Jeffrey N.; Zhang, Yuhan; Lu, Thomas T.; Chao, Tien-Hsin

    2012-04-01

    Automated Target Recognition (ATR) systems aim to automate target detection, recognition, and tracking. The current project applies a JPL ATR system to low-resolution sonar and camera videos taken from unmanned vehicles. These sonar images are inherently noisy and difficult to interpret, and pictures taken underwater were unreliable due to murkiness and inconsistent lighting. The ATR system breaks target recognition into three stages: 1) Videos of both sonar and camera footage are broken into frames and preprocessed to enhance images and detect Regions of Interest (ROIs). 2) Features are extracted from these ROIs in preparation for classification. 3) ROIs are classified as true or false positives using a standard Neural Network based on the extracted features. Several preprocessing, feature extraction, and training methods are tested and discussed in this report.

  18. Bilingual Word Recognition in Deaf and Hearing Signers: Effects of Proficiency and Language Dominance on Cross-Language Activation

    ERIC Educational Resources Information Center

    Morford, Jill P.; Kroll, Judith F.; Piñar, Pilar; Wilkinson, Erin

    2014-01-01

    Recent evidence demonstrates that American Sign Language (ASL) signs are active during print word recognition in deaf bilinguals who are highly proficient in both ASL and English. In the present study, we investigate whether signs are active during print word recognition in two groups of unbalanced bilinguals: deaf ASL-dominant and hearing…

  19. The Relationship between Word and Stress Pattern Recognition Ability and Hearing Level in Hearing-Impaired Young Adults.

    ERIC Educational Resources Information Center

    Jackson, Pamela; Kelly-Ballweber, Denise

    1986-01-01

    The relationship between word and stress pattern recognition ability and hearing level was explored by administering the Children's Auditory Test to hearing-impaired young adults (N=27). For word recognition, subjects with average hearing loss between 85 and 100 decibels demonstrated a wide range of performance not predictable from their…

  20. Parafoveal X-masks interfere with foveal word recognition: evidence from fixation-related brain potentials.

    PubMed

    Hutzler, Florian; Fuchs, Isabella; Gagl, Benjamin; Schuster, Sarah; Richlan, Fabio; Braun, Mario; Hawelka, Stefan

    2013-01-01

    The boundary paradigm, in combination with parafoveal masks, is the main technique for studying parafoveal preprocessing during reading. The rationale is that the masks (e.g., strings of X's) prevent parafoveal preprocessing, but do not interfere with foveal processing. A recent study, however, raised doubts about the neutrality of parafoveal masks. In the present study, we explored this issue by means of fixation-related brain potentials (FRPs). Two FRP conditions presented rows of five words. The task of the participant was to judge whether the final word of a list was a "new" word, or whether it was a repeated (i.e., "old") word. The critical manipulation was that the final word was X-masked during parafoveal preview in one condition, whereas another condition presented a valid preview of the word. In two additional event-related brain potential (ERP) conditions, the words were presented serially with no parafoveal preview available; in one of the conditions with a fixed timing, in the other word presentation was self-paced by the participants. Expectedly, the valid-preview FRP condition elicited the shortest processing times. Processing times did not differ between the two ERP conditions indicating that "cognitive readiness" during self-paced processing can be ruled out as an alternative explanation for differences in processing times between the ERP and the FRP conditions. The longest processing times were found in the X-mask FRP condition indicating that parafoveal X-masks interfere with foveal word recognition.

  1. Neural Correlates of Word Recognition: A Systematic Comparison of Natural Reading and Rapid Serial Visual Presentation.

    PubMed

    Kornrumpf, Benthe; Niefind, Florian; Sommer, Werner; Dimigen, Olaf

    2016-09-01

    Neural correlates of word recognition are commonly studied with (rapid) serial visual presentation (RSVP), a condition that eliminates three fundamental properties of natural reading: parafoveal preprocessing, saccade execution, and the fast changes in attentional processing load occurring from fixation to fixation. We combined eye-tracking and EEG to systematically investigate the impact of all three factors on brain-electric activity during reading. Participants read lists of words either actively with eye movements (eliciting fixation-related potentials) or maintained fixation while the text moved passively through foveal vision at a matched pace (RSVP-with-flankers paradigm, eliciting ERPs). The preview of the upcoming word was manipulated by changing the number of parafoveally visible letters. Processing load was varied by presenting words of varying lexical frequency. We found that all three factors have strong interactive effects on the brain's responses to words: Once a word was fixated, occipitotemporal N1 amplitude decreased monotonically with the amount of parafoveal information available during the preceding fixation; hence, the N1 component was markedly attenuated under reading conditions with preview. Importantly, this preview effect was substantially larger during active reading (with saccades) than during passive RSVP with flankers, suggesting that the execution of eye movements facilitates word recognition by increasing parafoveal preprocessing. Lastly, we found that the N1 component elicited by a word also reflects the lexical processing load imposed by the previously inspected word. Together, these results demonstrate that, under more natural conditions, words are recognized in a spatiotemporally distributed and interdependent manner across multiple eye fixations, a process that is mediated by active motor behavior. PMID:27167402

  2. Neural Correlates of Word Recognition: A Systematic Comparison of Natural Reading and Rapid Serial Visual Presentation.

    PubMed

    Kornrumpf, Benthe; Niefind, Florian; Sommer, Werner; Dimigen, Olaf

    2016-09-01

    Neural correlates of word recognition are commonly studied with (rapid) serial visual presentation (RSVP), a condition that eliminates three fundamental properties of natural reading: parafoveal preprocessing, saccade execution, and the fast changes in attentional processing load occurring from fixation to fixation. We combined eye-tracking and EEG to systematically investigate the impact of all three factors on brain-electric activity during reading. Participants read lists of words either actively with eye movements (eliciting fixation-related potentials) or maintained fixation while the text moved passively through foveal vision at a matched pace (RSVP-with-flankers paradigm, eliciting ERPs). The preview of the upcoming word was manipulated by changing the number of parafoveally visible letters. Processing load was varied by presenting words of varying lexical frequency. We found that all three factors have strong interactive effects on the brain's responses to words: Once a word was fixated, occipitotemporal N1 amplitude decreased monotonically with the amount of parafoveal information available during the preceding fixation; hence, the N1 component was markedly attenuated under reading conditions with preview. Importantly, this preview effect was substantially larger during active reading (with saccades) than during passive RSVP with flankers, suggesting that the execution of eye movements facilitates word recognition by increasing parafoveal preprocessing. Lastly, we found that the N1 component elicited by a word also reflects the lexical processing load imposed by the previously inspected word. Together, these results demonstrate that, under more natural conditions, words are recognized in a spatiotemporally distributed and interdependent manner across multiple eye fixations, a process that is mediated by active motor behavior.

  3. Acquisition of Malay Word Recognition Skills: Lessons from Low-Progress Early Readers

    ERIC Educational Resources Information Center

    Lee, Lay Wah; Wheldall, Kevin

    2011-01-01

    Malay is a consistent alphabetic orthography with complex syllable structures. The focus of this research was to investigate word recognition performance in order to inform reading interventions for low-progress early readers. Forty-six Grade 1 students were sampled and 11 were identified as low-progress readers. The results indicated that both…

  4. Phonological Activation during Visual Word Recognition in Deaf and Hearing Children

    ERIC Educational Resources Information Center

    Ormel, Ellen; Hermans, Daan; Knoors, Harry; Hendriks, Angelique; Verhoeven, Ludo

    2010-01-01

    Purpose: Phonological activation during visual word recognition was studied in deaf and hearing children under two circumstances: (a) when the use of phonology was not required for task performance and might even hinder it and (b) when the use of phonology was critical for task performance. Method: Deaf children mastering written Dutch and Sign…

  5. False recognition production indexes in Spanish for 60 DRM lists with three critical words.

    PubMed

    Beato, Maria Soledad; Díez, Emiliano

    2011-06-01

    A normative study was conducted using the Deese/Roediger-McDermott paradigm (DRM) to obtain false recognition for 60 six-word lists in Spanish, designed with a completely new methodology. For the first time, lists included words (e.g., bridal, newlyweds, bond, commitment, couple, to marry) simultaneously associated with three critical words (e.g., love, wedding, marriage). Backward associative strength between lists and critical words was taken into account when creating the lists. The results showed that all lists produced false recognition. Moreover, some lists had a high false recognition rate (e.g., 65%; jail, inmate, prison: bars, prisoner, cell, offender, penitentiary, imprisonment). This is an aspect of special interest for those DRM experiments that, for example, record brain electrical activity. This type of list will enable researchers to raise the signal-to-noise ratio in false recognition event-related potential studies as they increase the number of critical trials per list, and it will be especially useful for the design of future research. PMID:21298572

  6. The Influence of Semantic Constraints on Bilingual Word Recognition during Sentence Reading

    ERIC Educational Resources Information Center

    Van Assche, Eva; Drieghe, Denis; Duyck, Wouter; Welvaert, Marijke; Hartsuiker, Robert J.

    2011-01-01

    The present study investigates how semantic constraint of a sentence context modulates language-non-selective activation in bilingual visual word recognition. We recorded Dutch-English bilinguals' eye movements while they read cognates and controls in low and high semantically constraining sentences in their second language. Early and late…

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

    ERIC Educational Resources Information Center

    Ray, Suchismita; Bates, Marsha E.

    2006-01-01

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

  8. Methods for Sight Word Recognition in Kindergarten: Traditional Flashcard Method vs. Multisensory Approach

    ERIC Educational Resources Information Center

    Phillips, William E.; Feng, Jay

    2012-01-01

    A quasi-experimental action research with a pretest-posttest same subject design was implemented to determine if there is a different effect of the flash card method and the multisensory approach on kindergarteners' achievement in sight word recognition, and which method is more effective if there is any difference. Instrumentation for pretest and…

  9. Prediction of Word Recognition in the First Half of Grade 1

    ERIC Educational Resources Information Center

    Snel, M. J.; Aarnoutse, C. A. J.; Terwel, J.; van Leeuwe, J. F. J.; van der Veld, W. M.

    2016-01-01

    Early detection of reading problems is important to prevent an enduring lag in reading skills. We studied the relationship between speed of word recognition (after six months of grade 1 education) and four kindergarten pre-literacy skills: letter knowledge, phonological awareness and naming speed for both digits and letters. Our sample consisted…

  10. Examining the Time Course of Indexical Specificity Effects in Spoken Word Recognition

    ERIC Educational Resources Information Center

    McLennan, Conor T.; Luce, Paul A.

    2005-01-01

    Variability in talker identity and speaking rate, commonly referred to as indexical variation, has demonstrable effects on the speed and accuracy of spoken word recognition. The present study examines the time course of indexical specificity effects to evaluate the hypothesis that such effects occur relatively late in the perceptual processing of…

  11. Differences in Word Recognition between Early Bilinguals and Monolinguals: Behavioral and ERP Evidence

    ERIC Educational Resources Information Center

    Lehtonen, Minna; Hulten, Annika; Rodriguez-Fornells, Antoni; Cunillera, Toni; Tuomainen, Jyrki; Laine, Matti

    2012-01-01

    We investigated the behavioral and brain responses (ERPs) of bilingual word recognition to three fundamental psycholinguistic factors, frequency, morphology, and lexicality, in early bilinguals vs. monolinguals. Earlier behavioral studies have reported larger frequency effects in bilinguals' nondominant vs. dominant language and in some studies…

  12. Morphological Awareness and Early and Advanced Word Recognition and Spelling in Dutch

    ERIC Educational Resources Information Center

    Rispens, Judith E.; McBride-Chang, Catherine; Reitsma, Pieter

    2008-01-01

    This study investigated the relations of three aspects of morphological awareness to word recognition and spelling skills of Dutch speaking children. Tasks of inflectional and derivational morphology and lexical compounding, as well as measures of phonological awareness, vocabulary and mathematics were administered to 104 first graders (mean age 6…

  13. Prefixes as Access Units in Visual Word Recognition: A Comparison of Italian and Dutch Data.

    ERIC Educational Resources Information Center

    Assink, Egbert M. H.; Vooijs, Caroline; Knuijt, Paul P. N. A.

    2000-01-01

    Compares morphological processing of skilled and less skilled Dutch readers. Focuses on the role of prefixes as access units in visual word recognition. Finds evidence for differential use of prefix information in undergraduate students and elementary school children. Concludes that the information accessed by prefixes is semantically combined…

  14. An Evaluation of Project iRead: A Program Created to Improve Sight Word Recognition

    ERIC Educational Resources Information Center

    Marshall, Theresa Meade

    2014-01-01

    This program evaluation was undertaken to examine the relationship between participation in Project iRead and student gains in word recognition, fluency, and comprehension as measured by the Phonological Awareness Literacy Screening (PALS) Test. Linear regressions compared the 2012-13 PALS results from 5,140 first and second grade students at…

  15. fMRI of Two Measures of Phonological Processing in Visual Word Recognition: Ecological Validity Matters

    ERIC Educational Resources Information Center

    Owen, William J.; Borowsky, Ron; Sarty, Gordon E.

    2004-01-01

    Previous functional magnetic resonance imaging (fMRI) studies have investigated the role of phonological processing by utilizing nonword rhyming decision tasks (e.g., Pugh et al., 1996). Although such tasks clearly engage phonological components of visual word recognition, it is clear that decision tasks are more cognitively involved than the…

  16. Visual Word Recognition by Bilinguals in a Sentence Context: Evidence for Nonselective Lexical Access

    ERIC Educational Resources Information Center

    Duyck, Wouter; Van Assche, Eva; Drieghe, Denis; Hartsuiker, Robert J.

    2007-01-01

    Recent research on bilingualism has shown that lexical access in visual word recognition by bilinguals is not selective with respect to language. In the present study, the authors investigated language-independent lexical access in bilinguals reading sentences, which constitutes a strong unilingual linguistic context. In the first experiment,…

  17. Teaching Word Recognition to Children with Severe Learning Difficulties: An Exploratory Comparison of Teaching Methods

    ERIC Educational Resources Information Center

    Sheehy, Kieron

    2009-01-01

    Background: Some children with severe learning difficulties fail to begin word recognition. For these children there is a need for an effective and appropriate pedagogy. However, conflicting advice can be found regarding this derived from teaching approaches that are not based on a shared understanding of how reading develops or the skills that…

  18. Early Decomposition in Visual Word Recognition: Dissociating Morphology, Form, and Meaning

    ERIC Educational Resources Information Center

    Marslen-Wilson, William D.; Bozic, Mirjana; Randall, Billi

    2008-01-01

    The role of morphological, semantic, and form-based factors in the early stages of visual word recognition was investigated across different SOAs in a masked priming paradigm, focusing on English derivational morphology. In a first set of experiments, stimulus pairs co-varying in morphological decomposability and in semantic and orthographic…

  19. The Impact of Orthographic Connectivity on Visual Word Recognition in Arabic: A Cross-Sectional Study

    ERIC Educational Resources Information Center

    Khateb, Asaid; Khateb-Abdelgani, Manal; Taha, Haitham Y.; Ibrahim, Raphiq

    2014-01-01

    This study aimed at assessing the effects of letters' connectivity in Arabic on visual word recognition. For this purpose, reaction times (RTs) and accuracy scores were collected from ninety-third, sixth and ninth grade native Arabic speakers during a lexical decision task, using fully connected (Cw), partially connected (PCw) and…

  20. Electrophysiological Markers of Syllable Frequency during Written Word Recognition in French

    ERIC Educational Resources Information Center

    Chetail, Fabienne; Colin, Cecile; Content, Alain

    2012-01-01

    Several empirical lines of investigation support the idea that syllable-sized units may be involved in visual word recognition processes. In this perspective, the present study aimed at investigating further the nature of the process that causes syllabic effects in reading. To do so, the syllable frequency effect was investigated in French using…

  1. Onset of Word Form Recognition in English, Welsh, and English-Welsh Bilingual Infants

    ERIC Educational Resources Information Center

    Vihman, Marilyn May; Thierry, Guillaume; Lum, Jarrad; Keren-Portnoy, Tamar; Martin, Pam

    2007-01-01

    Children raised in the home as English or Welsh monolinguals or English-Welsh bilinguals were tested on untrained word form recognition using both behavioral and neurophysiological procedures. Behavioral measures confirmed the onset of a familiarity effect at 11 months in English but failed to identify it in monolingual Welsh infants between 9 and…

  2. Short-Term and Long-Term Effects on Visual Word Recognition

    ERIC Educational Resources Information Center

    Protopapas, Athanassios; Kapnoula, Efthymia C.

    2016-01-01

    Effects of lexical and sublexical variables on visual word recognition are often treated as homogeneous across participants and stable over time. In this study, we examine the modulation of frequency, length, syllable and bigram frequency, orthographic neighborhood, and graphophonemic consistency effects by (a) individual differences, and (b) item…

  3. Collaborative Efforts to Promote Emergent Literacy and Efficient Word Recognition Skills

    ERIC Educational Resources Information Center

    Roth, Froma P.; Troia, Gary A.

    2006-01-01

    In this article, 3 models of collaboration between speech-language pathologists and classroom teachers are discussed to promote emergent literacy and accurate and fluent word recognition. These models are demonstration lessons, team teaching, and consultation. A number of instructional principles are presented for emergent literacy and decoding…

  4. Validating Models of Clinical Word Recognition Tests for Spanish/English Bilinguals

    ERIC Educational Resources Information Center

    Shi, Lu-Feng

    2014-01-01

    Purpose: Shi and Sánchez (2010) developed models to predict the optimal test language for evaluating Spanish/English (S/E) bilinguals' word recognition. The current study intended to validate their conclusions in a separate bilingual listener sample. Method: Seventy normal-hearing S/E bilinguals varying in language profile were included.…

  5. Processing Strategy and PI Effects in Recognition Memory of Word Lists.

    ERIC Educational Resources Information Center

    Hodge, Milton H.; Britton, Bruce K.

    Previous research by A. I. Schulman argued that an observed systematic decline in recognition memory in long word lists was due to the build-up of input and output proactive interference (PI). It also suggested that input PI resulted from process automatization; that is, each list item was processed or encoded in much the same way, producing a set…

  6. The Reading Process--The Relationship Between Word Recognition and Comprehension.

    ERIC Educational Resources Information Center

    Hays, Warren S.

    The purpose of this study was to determine the relationship between word recognition and comprehension achieved by second and fifth grade students when reading material at various levels of readability. A random sample of twenty-five second and twenty-five fifth graders, taken from three middle class schools, was administered a…

  7. Letter Names: Effect on Letter Saying, Spelling, and Word Recognition in Hebrew.

    ERIC Educational Resources Information Center

    Levin, Iris; Patel, Sigal; Margalit, Tamar; Barad, Noa

    2002-01-01

    Examined whether letter names, which bridge the gap between oral and written language among English speaking children, have a similar function in Hebrew. In findings from studies of Israeli kindergartners and first graders, children were found to rely on letter names in performing a number of letter saying, spelling, and word recognition tasks.…

  8. Learning of Letter Names and Sounds and Their Contribution to Word Recognition

    ERIC Educational Resources Information Center

    Levin, Iris; Shatil-Carmon, Sivan; Asif-Rave, Ornit

    2006-01-01

    This study investigated knowledge of letter names and letter sounds, their learning, and their contributions to word recognition. Of 123 preschoolers examined on letter knowledge, 65 underwent training on both letter names and letter sounds in a counterbalanced order. Prior to training, children were more advanced in associating letters with their…

  9. ASL Handshape Stories, Word Recognition and Signing Deaf Readers: An Exploratory Study

    ERIC Educational Resources Information Center

    Gietz, Merrilee R.

    2013-01-01

    The effectiveness of using American Sign Language (ASL) handshape stories to teach word recognition in whole stories using a descriptive case study approach was explored. Four profoundly deaf children ages 7 to 8, enrolled in a self-contained deaf education classroom in a public school in the south participated in the story time five-week…

  10. Putting It All Together: A Unified Account of Word Recognition and Reaction-Time Distributions

    ERIC Educational Resources Information Center

    Norris, Dennis

    2009-01-01

    R. Ratcliff, P. Gomez, and G. McKoon (2004) suggested much of what goes on in lexical decision is attributable to decision processes and may not be particularly informative about word recognition. They proposed that lexical decision should be characterized by a decision process, taking the form of a drift-diffusion model (R. Ratcliff, 1978), that…

  11. Effective connectivity of visual word recognition and homophone orthographic errors

    PubMed Central

    Guàrdia-Olmos, Joan; Peró-Cebollero, Maribel; Zarabozo-Hurtado, Daniel; González-Garrido, Andrés A.; Gudayol-Ferré, Esteve

    2015-01-01

    The study of orthographic errors in a transparent language like Spanish is an important topic in relation to writing acquisition. The development of neuroimaging techniques, particularly functional magnetic resonance imaging (fMRI), has enabled the study of such relationships between brain areas. The main objective of the present study was to explore the patterns of effective connectivity by processing pseudohomophone orthographic errors among subjects with high and low spelling skills. Two groups of 12 Mexican subjects each, matched by age, were formed based on their results in a series of ad hoc spelling-related out-scanner tests: a high spelling skills (HSSs) group and a low spelling skills (LSSs) group. During the f MRI session, two experimental tasks were applied (spelling recognition task and visuoperceptual recognition task). Regions of Interest and their signal values were obtained for both tasks. Based on these values, structural equation models (SEMs) were obtained for each group of spelling competence (HSS and LSS) and task through maximum likelihood estimation, and the model with the best fit was chosen in each case. Likewise, dynamic causal models (DCMs) were estimated for all the conditions across tasks and groups. The HSS group’s SEM results suggest that, in the spelling recognition task, the right middle temporal gyrus, and, to a lesser extent, the left parahippocampal gyrus receive most of the significant effects, whereas the DCM results in the visuoperceptual recognition task show less complex effects, but still congruent with the previous results, with an important role in several areas. In general, these results are consistent with the major findings in partial studies about linguistic activities but they are the first analyses of statistical effective brain connectivity in transparent languages. PMID:26042070

  12. Parallel language activation and cognitive control during spoken word recognition in bilinguals

    PubMed Central

    Blumenfeld, Henrike K.; Marian, Viorica

    2013-01-01

    Accounts of bilingual cognitive advantages suggest an associative link between cross-linguistic competition and inhibitory control. We investigate this link by examining English-Spanish bilinguals’ parallel language activation during auditory word recognition and nonlinguistic Stroop performance. Thirty-one English-Spanish bilinguals and 30 English monolinguals participated in an eye-tracking study. Participants heard words in English (e.g., comb) and identified corresponding pictures from a display that included pictures of a Spanish competitor (e.g., conejo, English rabbit). Bilinguals with higher Spanish proficiency showed more parallel language activation and smaller Stroop effects than bilinguals with lower Spanish proficiency. Across all bilinguals, stronger parallel language activation between 300–500ms after word onset was associated with smaller Stroop effects; between 633–767ms, reduced parallel language activation was associated with smaller Stroop effects. Results suggest that bilinguals who perform well on the Stroop task show increased cross-linguistic competitor activation during early stages of word recognition and decreased competitor activation during later stages of word recognition. Findings support the hypothesis that cross-linguistic competition impacts domain-general inhibition. PMID:24244842

  13. Clustering of Farsi sub-word images for whole-book recognition

    NASA Astrophysics Data System (ADS)

    Soheili, Mohammad Reza; Kabir, Ehsanollah; Stricker, Didier

    2015-01-01

    Redundancy of word and sub-word occurrences in large documents can be effectively utilized in an OCR system to improve recognition results. Most OCR systems employ language modeling techniques as a post-processing step; however these techniques do not use important pictorial information that exist in the text image. In case of large-scale recognition of degraded documents, this information is even more valuable. In our previous work, we proposed a subword image clustering method for the applications dealing with large printed documents. In our clustering method, the ideal case is when all equivalent sub-word images lie in one cluster. To overcome the issues of low print quality, the clustering method uses an image matching algorithm for measuring the distance between two sub-word images. The measured distance with a set of simple shape features were used to cluster all sub-word images. In this paper, we analyze the effects of adding more shape features on processing time, purity of clustering, and the final recognition rate. Previously published experiments have shown the efficiency of our method on a book. Here we present extended experimental results and evaluate our method on another book with totally different font face. Also we show that the number of the new created clusters in a page can be used as a criteria for assessing the quality of print and evaluating preprocessing phases.

  14. Relationships among vocabulary size, nonverbal cognition, and spoken word recognition in adults with cochlear implants

    NASA Astrophysics Data System (ADS)

    Collison, Elizabeth A.; Munson, Benjamin; Carney, Arlene E.

    2002-05-01

    Recent research has attempted to identify the factors that predict speech perception performance among users of cochlear implants (CIs). Studies have found that approximately 20%-60% of the variance in speech perception scores can be accounted for by factors including duration of deafness, etiology, type of device, and length of implant use, leaving approximately 50% of the variance unaccounted for. The current study examines the extent to which vocabulary size and nonverbal cognitive ability predict CI listeners' spoken word recognition. Fifteen postlingually deafened adults with nucleus or clarion CIs were given standardized assessments of nonverbal cognitive ability and expressive vocabulary size: the Expressive Vocabulary Test, the Test of Nonverbal Intelligence-III, and the Woodcock-Johnson-III Test of Cognitive Ability, Verbal Comprehension subtest. Two spoken word recognition tasks were administered. In the first, listeners identified isophonemic CVC words. In the second, listeners identified gated words varying in lexical frequency and neighborhood density. Analyses will examine the influence of lexical frequency and neighborhood density on the uniqueness point in the gating task, as well as relationships among nonverbal cognitive ability, vocabulary size, and the two spoken word recognition measures. [Work supported by NIH Grant P01 DC00110 and by the Lions 3M Hearing Foundation.

  15. Parallel language activation and cognitive control during spoken word recognition in bilinguals.

    PubMed

    Blumenfeld, Henrike K; Marian, Viorica

    2013-01-01

    Accounts of bilingual cognitive advantages suggest an associative link between cross-linguistic competition and inhibitory control. We investigate this link by examining English-Spanish bilinguals' parallel language activation during auditory word recognition and nonlinguistic Stroop performance. Thirty-one English-Spanish bilinguals and 30 English monolinguals participated in an eye-tracking study. Participants heard words in English (e.g., comb) and identified corresponding pictures from a display that included pictures of a Spanish competitor (e.g., conejo, English rabbit). Bilinguals with higher Spanish proficiency showed more parallel language activation and smaller Stroop effects than bilinguals with lower Spanish proficiency. Across all bilinguals, stronger parallel language activation between 300-500ms after word onset was associated with smaller Stroop effects; between 633-767ms, reduced parallel language activation was associated with smaller Stroop effects. Results suggest that bilinguals who perform well on the Stroop task show increased cross-linguistic competitor activation during early stages of word recognition and decreased competitor activation during later stages of word recognition. Findings support the hypothesis that cross-linguistic competition impacts domain-general inhibition. PMID:24244842

  16. Speech-perception training for older adults with hearing loss impacts word recognition and effort.

    PubMed

    Kuchinsky, Stefanie E; Ahlstrom, Jayne B; Cute, Stephanie L; Humes, Larry E; Dubno, Judy R; Eckert, Mark A

    2014-10-01

    The current pupillometry study examined the impact of speech-perception training on word recognition and cognitive effort in older adults with hearing loss. Trainees identified more words at the follow-up than at the baseline session. Training also resulted in an overall larger and faster peaking pupillary response, even when controlling for performance and reaction time. Perceptual and cognitive capacities affected the peak amplitude of the pupil response across participants but did not diminish the impact of training on the other pupil metrics. Thus, we demonstrated that pupillometry can be used to characterize training-related and individual differences in effort during a challenging listening task. Importantly, the results indicate that speech-perception training not only affects overall word recognition, but also a physiological metric of cognitive effort, which has the potential to be a biomarker of hearing loss intervention outcome.

  17. Examining the effects of variation in emotional tone of voice on spoken word recognition.

    PubMed

    Krestar, Maura L; McLennan, Conor T

    2013-09-01

    Emotional tone of voice (ETV) is essential for optimal verbal communication. Research has found that the impact of variation in nonlinguistic features of speech on spoken word recognition differs according to a time course. In the current study, we investigated whether intratalker variation in ETV follows the same time course in two long-term repetition priming experiments. We found that intratalker variability in ETVs affected reaction times to spoken words only when processing was relatively slow and difficult, not when processing was relatively fast and easy. These results provide evidence for the use of both abstract and episodic lexical representations for processing within-talker variability in ETV, depending on the time course of spoken word recognition.

  18. Speech-perception training for older adults with hearing loss impacts word recognition and effort

    PubMed Central

    Kuchinsky, Stefanie E.; Ahlstrom, Jayne B.; Cute, Stephanie L.; Humes, Larry E.; Dubno, Judy R.; Eckert, Mark A.

    2014-01-01

    The current pupillometry study examined the impact of speech-perception training on word recognition and cognitive effort in older adults with hearing loss. Trainees identified more words at the follow-up than at the baseline session. Training also resulted in an overall larger and faster peaking pupillary response, even when controlling for performance and reaction time. Perceptual and cognitive capacities affected the peak amplitude of the pupil response across participants but did not diminish the impact of training on the other pupil metrics. Thus, we demonstrated that pupillometry can be used to characterize training-related and individual differences in effort during a challenging listening task. Importantly, the results indicate that speech-perception training not only affects overall word recognition, but also a physiological metric of cognitive effort, which has the potential to be a biomarker of hearing loss intervention outcome. PMID:24909603

  19. Speech-perception training for older adults with hearing loss impacts word recognition and effort.

    PubMed

    Kuchinsky, Stefanie E; Ahlstrom, Jayne B; Cute, Stephanie L; Humes, Larry E; Dubno, Judy R; Eckert, Mark A

    2014-10-01

    The current pupillometry study examined the impact of speech-perception training on word recognition and cognitive effort in older adults with hearing loss. Trainees identified more words at the follow-up than at the baseline session. Training also resulted in an overall larger and faster peaking pupillary response, even when controlling for performance and reaction time. Perceptual and cognitive capacities affected the peak amplitude of the pupil response across participants but did not diminish the impact of training on the other pupil metrics. Thus, we demonstrated that pupillometry can be used to characterize training-related and individual differences in effort during a challenging listening task. Importantly, the results indicate that speech-perception training not only affects overall word recognition, but also a physiological metric of cognitive effort, which has the potential to be a biomarker of hearing loss intervention outcome. PMID:24909603

  20. Is a Fan Always Fun? Phonological and Orthographic Effects in Bilingual Visual Word Recognition

    ERIC Educational Resources Information Center

    Ota, Mitsuhiko; Hartsuiker, Robert J.; Haywood, Sarah L.

    2010-01-01

    A visual semantic categorization task in English was performed by native English speakers (Experiment 1) and late bilinguals whose first language was Japanese (Experiment 2) or Spanish (Experiment 3). In the critical conditions, the target word was a homophone of a correct category exemplar (e.g., A BODY OF WATER-SEE; cf. SEA) or a word that…

  1. The Interaction of Lexical Semantics and Cohort Competition in Spoken Word Recognition: An fMRI Study

    ERIC Educational Resources Information Center

    Zhuang, Jie; Randall, Billi; Stamatakis, Emmanuel A.; Marslen-Wilson, William D.; Tyler, Lorraine K.

    2011-01-01

    Spoken word recognition involves the activation of multiple word candidates on the basis of the initial speech input--the "cohort"--and selection among these competitors. Selection may be driven primarily by bottom-up acoustic-phonetic inputs or it may be modulated by other aspects of lexical representation, such as a word's meaning…

  2. Dynamic and Contextual Information in HMM Modeling for Handwritten Word Recognition.

    PubMed

    Bianne-Bernard, Anne-Laure; Menasri, Farès; Al-Hajj Mohamad, Rami; Mokbel, Chafic; Kermorvant, Christopher; Likforman-Sulem, Laurence

    2011-10-01

    This study aims at building an efficient word recognition system resulting from the combination of three handwriting recognizers. The main component of this combined system is an HMM-based recognizer which considers dynamic and contextual information for a better modeling of writing units. For modeling the contextual units, a state-tying process based on decision tree clustering is introduced. Decision trees are built according to a set of expert-based questions on how characters are written. Questions are divided into global questions, yielding larger clusters, and precise questions, yielding smaller ones. Such clustering enables us to reduce the total number of models and Gaussians densities by 10. We then apply this modeling to the recognition of handwritten words. Experiments are conducted on three publicly available databases based on Latin or Arabic languages: Rimes, IAM, and OpenHart. The results obtained show that contextual information embedded with dynamic modeling significantly improves recognition.

  3. Reconsidering the role of orthographic redundancy in visual word recognition

    PubMed Central

    Chetail, Fabienne

    2015-01-01

    Humans are known to continuously extract regularities from the flow of stimulation. This occurs in many facets of behavior, including reading. In spite of the ubiquitous evidence that readers become sensitive to orthographic regularities after very little exposure to print, the role of orthographic regularities receives at best a peripheral status in current theories of orthographic processing. In the present article, after the presentation of previous evidence on orthographic redundancy, the hypothesis that orthographic regularities may play a prominent role in word perception is developed. PMID:26042074

  4. Method on camouflaged target recognition using the angle of ellipsometry

    NASA Astrophysics Data System (ADS)

    Zhuansun, Xiao-bo; Wu, Wen-Yuan; Huang, Yan-hua; Li, Zhao-zhao

    2015-10-01

    Using polarimetric information of the camouflaged target surface to identify camouflage has been a hot research area in camouflage detecting. The main method is to use the difference in the degree of polarization(DOP) between background and target to add the contrast ratio of them. The measurement of the DOP has some requirements on the intensity of reflected radiation. In case of low reflected radiation intensity, the difference in the DOP for different materials is not so distinguishable. In addition, the linear degree of polarization is largely under the effects of detection angle and surface roughness, so it is hard to differentiate the degree of polarization when the targets with similar surface roughness are detected at the same detection angle. By analyzing the elements affecting the reflected electromagnetic radiation amplitudes and phase on the camouflaged target surface, this article makes a research on the polarization character of reflected radiation A method on camouflaged target recognition directly or indirectly by taking the angle of ellipsometry (AOE) imaging under the linear polarized light. The function model of the angle of incidence, complex refractive index and AOE was modeled, then the model was simulated by MATLAB and the results showed it can describe the distribution properties of AOE. A new thought for the approach of identifying camouflaged target recognition by detecting polarimetric information was proposed, and it has a deep theoretical and practical significance in camouflaged target recognition.

  5. Lexical Influences on Spoken Spondaic Word Recognition in Hearing-Impaired Patients

    PubMed Central

    Moulin, Annie; Richard, Céline

    2015-01-01

    Top-down contextual influences play a major part in speech understanding, especially in hearing-impaired patients with deteriorated auditory input. Those influences are most obvious in difficult listening situations, such as listening to sentences in noise but can also be observed at the word level under more favorable conditions, as in one of the most commonly used tasks in audiology, i.e., repeating isolated words in silence. This study aimed to explore the role of top-down contextual influences and their dependence on lexical factors and patient-specific factors using standard clinical linguistic material. Spondaic word perception was tested in 160 hearing-impaired patients aged 23–88 years with a four-frequency average pure-tone threshold ranging from 21 to 88 dB HL. Sixty spondaic words were randomly presented at a level adjusted to correspond to a speech perception score ranging between 40 and 70% of the performance intensity function obtained using monosyllabic words. Phoneme and whole-word recognition scores were used to calculate two context-influence indices (the j factor and the ratio of word scores to phonemic scores) and were correlated with linguistic factors, such as the phonological neighborhood density and several indices of word occurrence frequencies. Contextual influence was greater for spondaic words than in similar studies using monosyllabic words, with an overall j factor of 2.07 (SD = 0.5). For both indices, context use decreased with increasing hearing loss once the average hearing loss exceeded 55 dB HL. In right-handed patients, significantly greater context influence was observed for words presented in the right ears than for words presented in the left, especially in patients with many years of education. The correlations between raw word scores (and context influence indices) and word occurrence frequencies showed a significant age-dependent effect, with a stronger correlation between perception scores and word occurrence frequencies

  6. Perceptual flexibility in word recognition: strategies affect orthographic computation but not lexical access.

    PubMed

    Carr, T H; Davidson, B J; Hawkins, H L

    1978-11-01

    Four tachistoscopic forced-choice recognition experiments explored the flexibility of processes underlying word perception. Stimuli were words, orthographically regular but unfamiliar pseudowords, and orthographically irregular nonsense strings. In the first two experiments, subjects knew that several different kinds of stimuli would occur in each block of trials and that one kind would occur much more often than the others. No matter which stimulus subjects expected to see most often, accuracy on words and pseudowords differed little, and both were identified considerably better than nonsense. In the third and fourth experiments, subjects were led to believe that only on stimulus type would occur but were surreptitiously shown another type on a small number of trials. Words were again identified more accurately than nonsense, and the size of the effect was independent of expectations. However, when either words or nonsense strings were expected exclusively, pseudoword accuracy did not differ from nonsense accuracy. Only when subjects knew that pseudowords would occur did they identify pseudowords more accurately than nonsense. This dissociation between word and pseudoword identification indicates the operation of two independent encoding mechanisms during tachistoscopic recognition, a stimulus-specific or logogenlike system sensitive to particular familiar strings and an orthographic mechanism sensitive to generally applicable constraints on letter sequencing. The stimulus-specific mechanism appears to be utilized automatically, but use of the orthographic mechanism is under strategic control. As shown in the first two experiments, however, rather extraordinary measures were required to demonstrate the flexibility of the orthographic processes used in this task. PMID:722255

  7. Wavelet-based learning vector quantization for automatic target recognition

    NASA Astrophysics Data System (ADS)

    Chan, Lipchen A.; Nasrabadi, Nasser M.; Mirelli, Vincent

    1996-06-01

    An automatic target recognition classifier is constructed that uses a set of dedicated vector quantizers (VQs). The background pixels in each input image are properly clipped out by a set of aspect windows. The extracted target area for each aspect window is then enlarged to a fixed size, after which a wavelet decomposition splits the enlarged extraction into several subbands. A dedicated VQ codebook is generated for each subband of a particular target class at a specific range of aspects. Thus, each codebook consists of a set of feature templates that are iteratively adapted to represent a particular subband of a given target class at a specific range of aspects. These templates are then further trained by a modified learning vector quantization (LVQ) algorithm that enhances their discriminatory characteristics. A recognition rate of 69.0 percent is achieved on a highly cluttered test set.

  8. The control of working memory resources in intentional forgetting: evidence from incidental probe word recognition.

    PubMed

    Fawcett, Jonathan M; Taylor, Tracy L

    2012-01-01

    We combined an item-method directed forgetting paradigm with a secondary task requiring a response to discriminate the color of probe words presented 1400 ms, 1800 ms or 2600 ms following each study phase memory instruction. The speed to make the color discrimination was used to assess the cognitive demands associated with instantiating Remember (R) and Forget (F) instructions; incidental memory for probe words was used to assess whether instantiating an F instruction also affects items presented in close temporal proximity. Discrimination responses were slower following F than R instructions at the two longest intervals. Critically, at the 1800 ms interval, incidental probe word recognition was worse following F than R instructions, particularly when the study word was successfully forgotten (as opposed to unintentionally remembered). We suggest that intentional forgetting is an active cognitive process associated with establishing control over the contents of working memory. PMID:22032824

  9. Recognition of Handwritten Arabic words using a neuro-fuzzy network

    SciTech Connect

    Boukharouba, Abdelhak; Bennia, Abdelhak

    2008-06-12

    We present a new method for the recognition of handwritten Arabic words based on neuro-fuzzy hybrid network. As a first step, connected components (CCs) of black pixels are detected. Then the system determines which CCs are sub-words and which are stress marks. The stress marks are then isolated and identified separately and the sub-words are segmented into graphemes. Each grapheme is described by topological and statistical features. Fuzzy rules are extracted from training examples by a hybrid learning scheme comprised of two phases: rule generation phase from data using a fuzzy c-means, and rule parameter tuning phase using gradient descent learning. After learning, the network encodes in its topology the essential design parameters of a fuzzy inference system.The contribution of this technique is shown through the significant tests performed on a handwritten Arabic words database.

  10. Conformal mapping-based hand-written word and sentence representation and recognition

    NASA Astrophysics Data System (ADS)

    Megherbi, Dalila B.; Iyassu, Yohannes; Boulenouar, A. J.

    2001-08-01

    In this paper, we introduce a technique for handwritten words and sentences representation and recognition. The proposed method is based on complex variables and conformal mapping methodology. In particular, in a previous work, through a complex variable methodology and conformal mapping process, we demonstrated the ability to recognized shapes and concisely represent shape boundaries using a set of polynomial coefficients derived in the mapping process. In this work we illustrate how these previous results can be applied to hand-written words and sentences. We show that the words/sentences classification techniques used are adapted to the feature-coefficients selected and are based on feature-coefficients similarities in combination with the minimum distance classifier. We use as measures the Euclidean distance as well as the covariance matrix eigen- values distance. Finally, experimental results of handwritten words and sentences are shown to show the power, versatility and robustness of the proposed technique.

  11. The word frequency effect in first- and second-language word recognition: a lexical entrenchment account.

    PubMed

    Diependaele, Kevin; Lemhöfer, Kristin; Brysbaert, Marc

    2013-01-01

    We investigate the origin of differences in the word frequency effect between native speakers and second-language speakers. In a large-scale analysis of English word identification times we find that group-level differences are fully accounted for by the individual language proficiency scores. Furthermore, exactly the same quantitative relation between word frequency and proficiency is found for monolinguals and three different bilingual populations (Dutch-English, French-English, and German-English). We conclude that the larger frequency effects for second-language processing than for native-language processing can be explained by within-language characteristics and thus need not be the consequence of "being bilingual" (i.e., a qualitative difference). More specifically, we argue that language proficiency increases lexical entrenchment, which leads to a reduced frequency effect, irrespective of bilingualism, language dominance, and language similarity.

  12. An Abundance of Riches: Cross-Task Comparisons of Semantic Richness Effects in Visual Word Recognition

    PubMed Central

    Yap, Melvin J.; Pexman, Penny M.; Wellsby, Michele; Hargreaves, Ian S.; Huff, Mark J.

    2012-01-01

    There is considerable evidence (e.g., Pexman et al., 2008) that semantically rich words, which are associated with relatively more semantic information, are recognized faster across different lexical processing tasks. The present study extends this earlier work by providing the most comprehensive evaluation to date of semantic richness effects on visual word recognition performance. Specifically, using mixed effects analyses to control for the influence of correlated lexical variables, we considered the impact of number of features, number of senses, semantic neighborhood density, imageability, and body–object interaction across five visual word recognition tasks: standard lexical decision, go/no-go lexical decision, speeded pronunciation, progressive demasking, and semantic classification. Semantic richness effects could be reliably detected in all tasks of lexical processing, indicating that semantic representations, particularly their imaginal and featural aspects, play a fundamental role in visual word recognition. However, there was also evidence that the strength of certain richness effects could be flexibly and adaptively modulated by task demands, consistent with an intriguing interplay between task-specific mechanisms and differentiated semantic processing. PMID:22529787

  13. The research of multi-frame target recognition based on laser active imaging

    NASA Astrophysics Data System (ADS)

    Wang, Can-jin; Sun, Tao; Wang, Tin-feng; Chen, Juan

    2013-09-01

    Laser active imaging is fit to conditions such as no difference in temperature between target and background, pitch-black night, bad visibility. Also it can be used to detect a faint target in long range or small target in deep space, which has advantage of high definition and good contrast. In one word, it is immune to environment. However, due to the affect of long distance, limited laser energy and atmospheric backscatter, it is impossible to illuminate the whole scene at the same time. It means that the target in every single frame is unevenly or partly illuminated, which make the recognition more difficult. At the same time the speckle noise which is common in laser active imaging blurs the images . In this paper we do some research on laser active imaging and propose a new target recognition method based on multi-frame images . Firstly, multi pulses of laser is used to obtain sub-images for different parts of scene. A denoising method combined homomorphic filter with wavelet domain SURE is used to suppress speckle noise. And blind deconvolution is introduced to obtain low-noise and clear sub-images. Then these sub-images are registered and stitched to combine a completely and uniformly illuminated scene image. After that, a new target recognition method based on contour moments is proposed. Firstly, canny operator is used to obtain contours. For each contour, seven invariant Hu moments are calculated to generate the feature vectors. At last the feature vectors are input into double hidden layers BP neural network for classification . Experiments results indicate that the proposed algorithm could achieve a high recognition rate and satisfactory real-time performance for laser active imaging.

  14. Team activity recognition in Association Football using a Bag-of-Words-based method.

    PubMed

    Montoliu, Raúl; Martín-Félez, Raúl; Torres-Sospedra, Joaquín; Martínez-Usó, Adolfo

    2015-06-01

    In this paper, a new methodology is used to perform team activity recognition and analysis in Association Football. It is based on pattern recognition and machine learning techniques. In particular, a strategy based on the Bag-of-Words (BoW) technique is used to characterize short Football video clips that are used to explain the team's performance and to train advanced classifiers in automatic recognition of team activities. In addition to the neural network-based classifier, three more classifier families are tested: the k-Nearest Neighbor, the Support Vector Machine and the Random Forest. The results obtained show that the proposed methodology is able to explain the most common movements of a team and to perform the team activity recognition task with high accuracy when classifying three Football actions: Ball Possession, Quick Attack and Set Piece. Random Forest is the classifier obtaining the best classification results.

  15. Automated target recognition and tracking using an optical pattern recognition neural network

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin

    1991-01-01

    The on-going development of an automatic target recognition and tracking system at the Jet Propulsion Laboratory is presented. This system is an optical pattern recognition neural network (OPRNN) that is an integration of an innovative optical parallel processor and a feature extraction based neural net training algorithm. The parallel optical processor provides high speed and vast parallelism as well as full shift invariance. The neural network algorithm enables simultaneous discrimination of multiple noisy targets in spite of their scales, rotations, perspectives, and various deformations. This fully developed OPRNN system can be effectively utilized for the automated spacecraft recognition and tracking that will lead to success in the Automated Rendezvous and Capture (AR&C) of the unmanned Cargo Transfer Vehicle (CTV). One of the most powerful optical parallel processors for automatic target recognition is the multichannel correlator. With the inherent advantages of parallel processing capability and shift invariance, multiple objects can be simultaneously recognized and tracked using this multichannel correlator. This target tracking capability can be greatly enhanced by utilizing a powerful feature extraction based neural network training algorithm such as the neocognitron. The OPRNN, currently under investigation at JPL, is constructed with an optical multichannel correlator where holographic filters have been prepared using the neocognitron training algorithm. The computation speed of the neocognitron-type OPRNN is up to 10(exp 14) analog connections/sec that enabling the OPRNN to outperform its state-of-the-art electronics counterpart by at least two orders of magnitude.

  16. Automatic target recognition using group-structured sparse representation

    NASA Astrophysics Data System (ADS)

    Sun, Bo; Wu, Xuewen; He, Jun; Zhu, Xiaoming; Chen, Chao

    2014-06-01

    Sparse representation classification method has been increasingly used in the fields of computer vision and pattern analysis, due to its high recognition rate, little dependence on the features, robustness to corruption and occlusion, and etc. However, most of these existing methods aim to find the sparsest representations of the test sample y in an overcomplete dictionary, which do not particularly consider the relevant structure between the atoms in the dictionary. Moreover, sufficient training samples are always required by the sparse representation method for effective recognition. In this paper we formulate the classification as a group-structured sparse representation problem using a sparsity-inducing norm minimization optimization and propose a novel sparse representation-based automatic target recognition (ATR) framework for the practical applications in which the training samples are drawn from the simulation models of real targets. The experimental results show that the proposed approach improves the recognition rate of standard sparse models, and our system can effectively and efficiently recognize targets under real environments, especially, where the good characteristics of the sparse representation based classification method are kept.

  17. Spoken Word Recognition and Serial Recall of Words from Components in the Phonological Network

    ERIC Educational Resources Information Center

    Siew, Cynthia S. Q.; Vitevitch, Michael S.

    2016-01-01

    Network science uses mathematical techniques to study complex systems such as the phonological lexicon (Vitevitch, 2008). The phonological network consists of a "giant component" (the largest connected component of the network) and "lexical islands" (smaller groups of words that are connected to each other, but not to the giant…

  18. AUDITORY-PHONETIC PROJECTION AND LEXICAL STRUCTURE IN THE RECOGNITION OF SINE-WAVE WORDS

    PubMed Central

    Remez, Robert E.; Dubowski, Kathryn R.; Broder, Robin S.; Davids, Morgana L.; Grossman, Yael S.; Moskalenko, Marina; Pardo, Jennifer S.; Hasbun, Sara Maria

    2010-01-01

    Speech remains intelligible despite the elimination of canonical acoustic correlates of phonemes from the spectrum. A portion of this perceptual flexibility can be attributed to modulation sensitivity in the auditory-to-phonetic projection, though signal-independent properties of lexical neighborhoods also affect intelligibility in utterances composed of words. Three tests were conducted to estimate the effects of exposure to natural and sine-wave samples of speech in this kind of perceptual versatility. First, sine-wave versions of the easy/hard word sets were created, modeled on the speech samples of a single talker. The performance difference in recognition of easy and hard words was used to index the perceptual reliance on signal-independent properties of lexical contrasts. Second, several kinds of exposure produced familiarity with an aspect of sine-wave speech: 1) sine-wave sentences modeled on the same talker; 2) sine-wave sentences modeled on a different talker, to create familiarity with a sine-wave carrier; and 3) natural sentences spoken by the same talker, to create familiarity with the idiolect expressed in the sine-wave words. Recognition performance with both easy and hard sine-wave words improved after exposure only to sine-wave sentences modeled on the same talker. Third, a control test showed that signal-independent uncertainty is a plausible cause of differences in recognition of easy and hard sine-wave words. The conditions of beneficial exposure reveal the specificity of attention underlying versatility in speech perception. PMID:20865138

  19. Bayesian multi-target tracking and sequential object recognition

    NASA Astrophysics Data System (ADS)

    Armbruster, Walter

    2008-04-01

    The paper considers the following problem: given a 3D model of a reference target and a sequence of images of a 3D scene, identify the object in the scene most likely to be the reference target and determine its current pose. Finding the best match in each frame independently of previous decisions is not optimal, since past information is ignored. Our solution concept uses a novel Bayesian framework for multi target tracking and object recognition to define and sequentially update the probability that the reference target is any one of the tracked objects. The approach is applied to problems of automatic lock-on and missile guidance using a laser radar seeker. Field trials have resulted in high target hit probabilities despite low resolution imagery and temporarily highly occluded targets.

  20. Effects of targets embedded within words in a visual search task

    PubMed Central

    Grabbe, Jeremy W.

    2014-01-01

    Visual search performance can be negatively affected when both targets and distracters share a dimension relevant to the task. This study examined if visual search performance would be influenced by distracters that affect a dimension irrelevant from the task. In Experiment 1 within the letter string of a letter search task, target letters were embedded within a word. Experiment 2 compared targets embedded in words to targets embedded in nonwords. Experiment 3 compared targets embedded in words to a condition in which a word was present in a letter string, but the target letter, although in the letter string, was not embedded within the word. The results showed that visual search performance was negatively affected when a target appeared within a high frequency word. These results suggest that the interaction and effectiveness of distracters is not merely dependent upon common features of the target and distracters, but can be affected by word frequency (a dimension not related to the task demands). PMID:24855497

  1. Automatic target recognition using vector quantization and neural networks

    NASA Astrophysics Data System (ADS)

    Chan, Lipchen A.; Nasrabadi, Nasser M.

    1999-12-01

    We propose an automatic target recognition (ATR) algorithm that uses a set of dedicated vector quantizers (VQs) and multilayer perceptrons (MLPs). For each target class at a specific range of aspects, the background pixels of an input image are first removed. The extracted target area is then subdivided into several subimages. A dedicated VQ codebook is constructed for each of the resulting subimages. Using the K-means algorithm, each VQ codebook learns a set of patterns representing the local features of a particular target for a specific range of aspects. The resulting codebooks are further trained by a modified learning vector quantization algorithm, which enhances the discriminatory power of the codebooks. Each final codebook is expected to give the lowest mean squared error (MSE) for its correct target class and range of aspects. These MSEs are then input to an array of window-level MLPs (WMLPs), where each WMLP is specialized in recognizing its intended target class for a specific range of aspects. The outputs of these WMLPs are manipulated and passed to a target-level MLP, which produces the final recognition results. We trained and tested the proposed ATR algorithm on large and realistic data sets and obtained impressive results using the wavelet-based adaptive produce VQs configuration.

  2. Advanced automatic target recognition for police helicopter missions

    NASA Astrophysics Data System (ADS)

    Stahl, Christoph; Schoppmann, Paul

    2000-08-01

    The results of a case study about the application of an advanced method for automatic target recognition to infrared imagery taken from police helicopter missions are presented. The method consists of the following steps: preprocessing, classification, fusion, postprocessing and tracking, and combines the three paradigms image pyramids, neural networks and bayesian nets. The technology has been developed using a variety of different scenes typical for military aircraft missions. Infrared cameras have been in use for several years at the Bavarian police helicopter forces and are highly valuable for night missions. Several object classes like 'persons' or 'vehicles' are tested and the possible discrimination between persons and animals is shown. The analysis of complex scenes with hidden objects and clutter shows the potentials and limitations of automatic target recognition for real-world tasks. Several display concepts illustrate the achievable improvement of the situation awareness. The similarities and differences between various mission types concerning object variability, time constraints, consequences of false alarms, etc. are discussed. Typical police actions like searching for missing persons or runaway criminals illustrate the advantages of automatic target recognition. The results demonstrate the possible operational benefits for the helicopter crew. Future work will include performance evaluation issues and a system integration concept for the target platform.

  3. Parafoveal X-masks interfere with foveal word recognition: evidence from fixation-related brain potentials

    PubMed Central

    Hutzler, Florian; Fuchs, Isabella; Gagl, Benjamin; Schuster, Sarah; Richlan, Fabio; Braun, Mario; Hawelka, Stefan

    2013-01-01

    The boundary paradigm, in combination with parafoveal masks, is the main technique for studying parafoveal preprocessing during reading. The rationale is that the masks (e.g., strings of X's) prevent parafoveal preprocessing, but do not interfere with foveal processing. A recent study, however, raised doubts about the neutrality of parafoveal masks. In the present study, we explored this issue by means of fixation-related brain potentials (FRPs). Two FRP conditions presented rows of five words. The task of the participant was to judge whether the final word of a list was a “new” word, or whether it was a repeated (i.e., “old”) word. The critical manipulation was that the final word was X-masked during parafoveal preview in one condition, whereas another condition presented a valid preview of the word. In two additional event-related brain potential (ERP) conditions, the words were presented serially with no parafoveal preview available; in one of the conditions with a fixed timing, in the other word presentation was self-paced by the participants. Expectedly, the valid-preview FRP condition elicited the shortest processing times. Processing times did not differ between the two ERP conditions indicating that “cognitive readiness” during self-paced processing can be ruled out as an alternative explanation for differences in processing times between the ERP and the FRP conditions. The longest processing times were found in the X-mask FRP condition indicating that parafoveal X-masks interfere with foveal word recognition. PMID:23888130

  4. A Study of Neural Word Embeddings for Named Entity Recognition in Clinical Text.

    PubMed

    Wu, Yonghui; Xu, Jun; Jiang, Min; Zhang, Yaoyun; Xu, Hua

    2015-01-01

    Clinical Named Entity Recognition (NER) is a critical task for extracting important patient information from clinical text to support clinical and translational research. This study explored the neural word embeddings derived from a large unlabeled clinical corpus for clinical NER. We systematically compared two neural word embedding algorithms and three different strategies for deriving distributed word representations. Two neural word embeddings were derived from the unlabeled Multiparameter Intelligent Monitoring in Intensive Care (MIMIC) II corpus (403,871 notes). The results from both 2010 i2b2 and 2014 Semantic Evaluation (SemEval) data showed that the binarized word embedding features outperformed other strategies for deriving distributed word representations. The binarized embedding features improved the F1-score of the Conditional Random Fields based clinical NER system by 2.3% on i2b2 data and 2.4% on SemEval data. The combined feature from the binarized embeddings and the Brown clusters improved the F1-score of the clinical NER system by 2.9% on i2b2 data and 2.7% on SemEval data. Our study also showed that the distributed word embedding features derived from a large unlabeled corpus can be better than the widely used Brown clusters. Further analysis found that the neural word embeddings captured a wide range of semantic relations, which could be discretized into distributed word representations to benefit the clinical NER system. The low-cost distributed feature representation can be adapted to any other clinical natural language processing research. PMID:26958273

  5. A Study of Neural Word Embeddings for Named Entity Recognition in Clinical Text

    PubMed Central

    Wu, Yonghui; Xu, Jun; Jiang, Min; Zhang, Yaoyun; Xu, Hua

    2015-01-01

    Clinical Named Entity Recognition (NER) is a critical task for extracting important patient information from clinical text to support clinical and translational research. This study explored the neural word embeddings derived from a large unlabeled clinical corpus for clinical NER. We systematically compared two neural word embedding algorithms and three different strategies for deriving distributed word representations. Two neural word embeddings were derived from the unlabeled Multiparameter Intelligent Monitoring in Intensive Care (MIMIC) II corpus (403,871 notes). The results from both 2010 i2b2 and 2014 Semantic Evaluation (SemEval) data showed that the binarized word embedding features outperformed other strategies for deriving distributed word representations. The binarized embedding features improved the F1-score of the Conditional Random Fields based clinical NER system by 2.3% on i2b2 data and 2.4% on SemEval data. The combined feature from the binarized embeddings and the Brown clusters improved the F1-score of the clinical NER system by 2.9% on i2b2 data and 2.7% on SemEval data. Our study also showed that the distributed word embedding features derived from a large unlabeled corpus can be better than the widely used Brown clusters. Further analysis found that the neural word embeddings captured a wide range of semantic relations, which could be discretized into distributed word representations to benefit the clinical NER system. The low-cost distributed feature representation can be adapted to any other clinical natural language processing research. PMID:26958273

  6. Manipulating letter fluency for words alters electrophysiological correlates of recognition memory

    PubMed Central

    Lucas, Heather D.; Paller, Ken A.

    2013-01-01

    The mechanisms that give rise to familiarity memory have received intense research interest. One current topic of debate concerns the extent to which familiarity is driven by the same fluency sources that give rise to certain implicit memory phenomena. Familiarity may be tied to conceptual fluency, given that familiarity and conceptual implicit memory can exhibit similar neurocognitive properties. However, familiarity can also be driven by perceptual factors, and its neural basis under these circumstances has received less attention. Here we recorded brain potentials during recognition testing using a procedure that has previously been shown to encourage a reliance on letter information when assessing familiarity for words. Studied and unstudied words were derived either from two separate letter pools or a single letter pool (“letter-segregated” and “normal” conditions, respectively) in a within-subjects contrast. As predicted, recognition accuracy was higher in the letter-segregated relative to the normal condition. Electrophysiological analyses revealed parietal old-new effects from 500–700 ms in both conditions. In addition, a topographically dissociable occipital old-new effect from 300–700 ms was present in the letter-segregated condition only. In a second experiment, we found that similar occipital brain potentials were associated with confident false recognition of words that shared letters with studied words but were not themselves studied. These findings indicate that familiarity is a multiply determined phenomenon, and that the stimulus dimensions on which familiarity is based can moderate its neural correlates. Conceptual and perceptual contributions to familiarity vary across testing circumstances, and both must be accounted for in theories of recognition memory and its neural basis. PMID:23871869

  7. Top-down modulation of ventral occipito-temporal responses during visual word recognition

    PubMed Central

    Twomey, Tae; Kawabata Duncan, Keith J.; Price, Cathy J.; Devlin, Joseph T.

    2011-01-01

    Although interactivity is considered a fundamental principle of cognitive (and computational) models of reading, it has received far less attention in neural models of reading that instead focus on serial stages of feed-forward processing from visual input to orthographic processing to accessing the corresponding phonological and semantic information. In particular, the left ventral occipito-temporal (vOT) cortex is proposed to be the first stage where visual word recognition occurs prior to accessing nonvisual information such as semantics and phonology. We used functional magnetic resonance imaging (fMRI) to investigate whether there is evidence that activation in vOT is influenced top-down by the interaction of visual and nonvisual properties of the stimuli during visual word recognition tasks. Participants performed two different types of lexical decision tasks that focused on either visual or nonvisual properties of the word or word-like stimuli. The design allowed us to investigate how vOT activation during visual word recognition was influenced by a task change to the same stimuli and by a stimulus change during the same task. We found both stimulus- and task-driven modulation of vOT activation that can only be explained by top-down processing of nonvisual aspects of the task and stimuli. Our results are consistent with the hypothesis that vOT acts as an interface linking visual form with nonvisual processing in both bottom up and top down directions. Such interactive processing at the neural level is in agreement with cognitive and computational models of reading but challenges some of the assumptions made by current neuro-anatomical models of reading. PMID:21232615

  8. Automated Target Acquisition, Recognition and Tracking (ATTRACT). Phase 1

    NASA Technical Reports Server (NTRS)

    Abdallah, Mahmoud A.

    1995-01-01

    The primary objective of phase 1 of this research project is to conduct multidisciplinary research that will contribute to fundamental scientific knowledge in several of the USAF critical technology areas. Specifically, neural networks, signal processing techniques, and electro-optic capabilities are utilized to solve problems associated with automated target acquisition, recognition, and tracking. To accomplish the stated objective, several tasks have been identified and were executed.

  9. Practical target recognition in infrared imagery using a neural network

    NASA Astrophysics Data System (ADS)

    Crowe, Alistair A.; Patel, A.; Wright, William A.; Green, Michael A.; Hughes, Andrew D.

    1992-07-01

    This paper describes work undertaken by British Aerospace (BAe) on the development of a neural network classifier for automatic recognition of land based targets in infrared imagery. The classifier used a histogram segmentation process to extract regions from the infrared imagery. A set of features were calculated for each region to form a feature vector describing the region. These feature vectors were then used as the input to the neural classifier. Two neural classifiers were investigated based upon the multi-layer perceptron and radial basis function networks. In order to assess the merits of a neural network approach, the neural classifiers were compared with a conventional classifier originally developed by British Aerospace (Systems and Equipment) Ltd., under contract to RARDE (Chertsey), for the purpose of infrared target recognition. This conventional system was based upon a Schurman classifier which operates on data transformed using a Hotelling Trace Transform. The ability of the classifiers to perform practical recognition of real-world targets was evaluated by training and testing the classifiers on real imagery obtained from mock land battles and military vehicle trials.

  10. Matching heard and seen speech: An ERP study of audiovisual word recognition.

    PubMed

    Kaganovich, Natalya; Schumaker, Jennifer; Rowland, Courtney

    2016-01-01

    Seeing articulatory gestures while listening to speech-in-noise (SIN) significantly improves speech understanding. However, the degree of this improvement varies greatly among individuals. We examined a relationship between two distinct stages of visual articulatory processing and the SIN accuracy by combining a cross-modal repetition priming task with ERP recordings. Participants first heard a word referring to a common object (e.g., pumpkin) and then decided whether the subsequently presented visual silent articulation matched the word they had just heard. Incongruent articulations elicited a significantly enhanced N400, indicative of a mismatch detection at the pre-lexical level. Congruent articulations elicited a significantly larger LPC, indexing articulatory word recognition. Only the N400 difference between incongruent and congruent trials was significantly correlated with individuals' SIN accuracy improvement in the presence of the talker's face. PMID:27155219

  11. The influence of print exposure on the body-object interaction effect in visual word recognition

    PubMed Central

    Hansen, Dana; Siakaluk, Paul D.; Pexman, Penny M.

    2012-01-01

    We examined the influence of print exposure on the body-object interaction (BOI) effect in visual word recognition. High print exposure readers and low print exposure readers either made semantic categorizations (“Is the word easily imageable?”; Experiment 1) or phonological lexical decisions (“Does the item sound like a real English word?”; Experiment 2). The results from Experiment 1 showed that there was a larger BOI effect for the low print exposure readers than for the high print exposure readers in semantic categorization, though an effect was observed for both print exposure groups. However, the results from Experiment 2 showed that the BOI effect was observed only for the high print exposure readers in phonological lexical decision. The results of the present study suggest that print exposure does influence the BOI effect, and that this influence varies as a function of task demands. PMID:22563312

  12. Decomposing encoding and decisional components in visual-word recognition: a diffusion model analysis.

    PubMed

    Gomez, Pablo; Perea, Manuel

    2014-01-01

    In a diffusion model, performance as measured by latency and accuracy in two-choice tasks is decomposed into different parameters that can be linked to underlying cognitive processes. Although the diffusion model has been utilized to account for lexical decision data, the effects of stimulus manipulations in previous experiments originated from just one parameter: the quality of the evidence. Here we examined whether the diffusion model can be used to effectively decompose the underlying processes during visual-word recognition. We explore this issue in an experiment that features a lexical manipulation (word frequency) that we expected to affect mostly the quality of the evidence (the drift rate parameter), and a perceptual manipulation (stimulus orientation) that presumably affects the nondecisional time (the Ter parameter, time of encoding and response) more than it affects the drift rate. Results showed that although the manipulations do not affect only one parameter, word frequency and stimulus orientation had differential effects on the model's parameters. Thus, the diffusion model is a useful tool to decompose the effects of stimulus manipulations in visual-word recognition. PMID:25192455

  13. Design and performance of a large vocabulary discrete word recognition system. Volume 2: Appendixes. [flow charts and users manual

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The users manual for the word recognition computer program contains flow charts of the logical diagram, the memory map for templates, the speech analyzer card arrangement, minicomputer input/output routines, and assembly language program listings.

  14. Some Considerations in Evaluating Spoken Word Recognition by Normal-Hearing, Noise-Masked Normal-Hearing, and Cochlear Implant Listeners. I: The Effects of Response Format

    PubMed Central

    Sommers, Mitchell S.; Kirk, Karen Iler; Pisoni, David B.

    2012-01-01

    Objective The purpose of the present studies was to assess the validity of using closed-set response formats to measure two cognitive processes essential for recognizing spoken words—perceptual normalization (the ability to accommodate acoustic-phonetic variability) and lexical discrimination (the ability to isolate words in the mental lexicon). In addition, the experiments were designed to examine the effects of response format on evaluation of these two abilities in normal-hearing (NH), noise-masked normal-hearing (NMNH), and cochlear implant (CI) subject populations. Design The speech recognition performance of NH, NMNH, and CI listeners was measured using both open- and closed-set response formats under a number of experimental conditions. To assess talker normalization abilities, identification scores for words produced by a single talker were compared with recognition performance for items produced by multiple talkers. To examine lexical discrimination, performance for words that are phonetically similar to many other words (hard words) was compared with scores for items with few phonetically similar competitors (easy words). Results Open-set word identification for all subjects was significantly poorer when stimuli were produced in lists with multiple talkers compared with conditions in which all of the words were spoken by a single talker. Open-set word recognition also was better for lexically easy compared with lexically hard words. Closed-set tests, in contrast, failed to reveal the effects of either talker variability or lexical difficulty even when the response alternatives provided were systematically selected to maximize confusability with target items. Conclusions These findings suggest that, although closed-set tests may provide important information for clinical assessment of speech perception, they may not adequately evaluate a number of cognitive processes that are necessary for recognizing spoken words. The parallel results obtained across

  15. What can we learn from learning models about sensitivity to letter-order in visual word recognition?

    PubMed Central

    Lerner, Itamar; Armstrong, Blair C.; Frost, Ram

    2014-01-01

    Recent research on the effects of letter transposition in Indo-European Languages has shown that readers are surprisingly tolerant of these manipulations in a range of tasks. This evidence has motivated the development of new computational models of reading that regard flexibility in positional coding to be a core and universal principle of the reading process. Here we argue that such approach does not capture cross-linguistic differences in transposed-letter effects, nor do they explain them. To address this issue, we investigated how a simple domain-general connectionist architecture performs in tasks such as letter-transposition and letter substitution when it had learned to process words in the context of different linguistic environments. The results show that in spite of of the neurobiological noise involved in registering letter-position in all languages, flexibility and inflexibility in coding letter order is also shaped by the statistical orthographic properties of words in a language, such as the relative prevalence of anagrams. Our learning model also generated novel predictions for targeted empirical research, demonstrating a clear advantage of learning models for studying visual word recognition. PMID:25431521

  16. Automated target recognition using passive radar and coordinated flight models

    NASA Astrophysics Data System (ADS)

    Ehrman, Lisa M.; Lanterman, Aaron D.

    2003-09-01

    Rather than emitting pulses, passive radar systems rely on illuminators of opportunity, such as TV and FM radio, to illuminate potential targets. These systems are particularly attractive since they allow receivers to operate without emitting energy, rendering them covert. Many existing passive radar systems estimate the locations and velocities of targets. This paper focuses on adding an automatic target recognition (ATR) component to such systems. Our approach to ATR compares the Radar Cross Section (RCS) of targets detected by a passive radar system to the simulated RCS of known targets. To make the comparison as accurate as possible, the received signal model accounts for aircraft position and orientation, propagation losses, and antenna gain patterns. The estimated positions become inputs for an algorithm that uses a coordinated flight model to compute probable aircraft orientation angles. The Fast Illinois Solver Code (FISC) simulates the RCS of several potential target classes as they execute the estimated maneuvers. The RCS is then scaled by the Advanced Refractive Effects Prediction System (AREPS) code to account for propagation losses that occur as functions of altitude and range. The Numerical Electromagnetic Code (NEC2) computes the antenna gain pattern, so that the RCS can be further scaled. The Rician model compares the RCS of the illuminated aircraft with those of the potential targets. This comparison results in target identification.

  17. Got Rhythm...For Better and for Worse. Cross-Modal Effects of Auditory Rhythm on Visual Word Recognition

    ERIC Educational Resources Information Center

    Brochard, Renaud; Tassin, Maxime; Zagar, Daniel

    2013-01-01

    The present research aimed to investigate whether, as previously observed with pictures, background auditory rhythm would also influence visual word recognition. In a lexical decision task, participants were presented with bisyllabic visual words, segmented into two successive groups of letters, while an irrelevant strongly metric auditory…

  18. Computational integral-imaging reconstruction-based 3-D volumetric target object recognition by using a 3-D reference object.

    PubMed

    Kim, Seung-Cheol; Park, Seok-Chan; Kim, Eun-Soo

    2009-12-01

    In this paper, we propose a novel computational integral-imaging reconstruction (CIIR)-based three-dimensional (3-D) image correlator system for the recognition of 3-D volumetric objects by employing a 3-D reference object. That is, a number of plane object images (POIs) computationally reconstructed from the 3-D reference object are used for the 3-D volumetric target recognition. In other words, simultaneous 3-D image correlations between two sets of target and reference POIs, which are depth-dependently reconstructed by using the CIIR method, are performed for effective recognition of 3-D volumetric objects in the proposed system. Successful experiments with this CIIR-based 3-D image correlator confirmed the feasibility of the proposed method.

  19. Developing normal reading skills: aspects of the visual processes underlying word recognition.

    PubMed

    Aghababian, V; Nazir, T A

    2000-06-01

    Visual word recognition performance of first graders (mean age: 6.6 years) through fifth graders (mean age: 10.8 years) was investigated using an experimental technique that is known to elicit the "viewing position effect" in skilled readers. The results showed that this effect, which consists of a systematic variation of performance as a function of fixation position within words, emerged early at the end of the 1st year of reading instruction. Visual field asymmetries in recognizing individual letters in words were also observed starting from first grade. Effects of word familiarity were obtained as early as in second grade. In contrast to skilled readers, children showed a marked word-length effect, which persisted through the first 5 years of instruction. No other qualitative differences between beginning and skilled readers were apparent. Hence, the basics of reading skills, as measured by the present technique, seem to be attained very early during acquisition. Further experience mainly reduces the time a reader needs to extract visual information from print. PMID:10788306

  20. ERPs reveal the temporal dynamics of auditory word recognition in specific language impairment.

    PubMed

    Malins, Jeffrey G; Desroches, Amy S; Robertson, Erin K; Newman, Randy Lynn; Archibald, Lisa M D; Joanisse, Marc F

    2013-07-01

    We used event-related potentials (ERPs) to compare auditory word recognition in children with specific language impairment (SLI group; N=14) to a group of typically developing children (TD group; N=14). Subjects were presented with pictures of items and heard auditory words that either matched or mismatched the pictures. Mismatches overlapped expected words in word-onset (cohort mismatches; see: DOLL, hear: dog), rhyme (CONE -bone), or were unrelated (SHELL -mug). In match trials, the SLI group showed a different pattern of N100 responses to auditory stimuli compared to the TD group, indicative of early auditory processing differences in SLI. However, the phonological mapping negativity (PMN) response to mismatching items was comparable across groups, suggesting that just like TD children, children with SLI are capable of establishing phonological expectations and detecting violations of these expectations in an online fashion. Perhaps most importantly, we observed a lack of attenuation of the N400 for rhyming words in the SLI group, which suggests that either these children were not as sensitive to rhyme similarity as their typically developing peers, or did not suppress lexical alternatives to the same extent. These findings help shed light on the underlying deficits responsible for SLI.

  1. The Role of Semantic Diversity in Word Recognition across Aging and Bilingualism

    PubMed Central

    Johns, Brendan T.; Sheppard, Christine L.; Jones, Michael N.; Taler, Vanessa

    2016-01-01

    Frequency effects are pervasive in studies of language, with higher frequency words being recognized faster than lower frequency words. However, the exact nature of frequency effects has recently been questioned, with some studies finding that contextual information provides a better fit to lexical decision and naming data than word frequency (Adelman et al., 2006). Recent work has cemented the importance of these results by demonstrating that a measure of the semantic diversity of the contexts that a word occurs in provides a powerful measure to account for variability in word recognition latency (Johns et al., 2012, 2015; Jones et al., 2012). The goal of the current study is to extend this measure to examine bilingualism and aging, where multiple theories use frequency of occurrence of linguistic constructs as central to accounting for empirical results (Gollan et al., 2008; Ramscar et al., 2014). A lexical decision experiment was conducted with four groups of subjects: younger and older monolinguals and bilinguals. Consistent with past results, a semantic diversity variable accounted for the greatest amount of variance in the latency data. In addition, the pattern of fits of semantic diversity across multiple corpora suggests that bilinguals and older adults are more sensitive to semantic diversity information than younger monolinguals. PMID:27458392

  2. The Role of Semantic Diversity in Word Recognition across Aging and Bilingualism.

    PubMed

    Johns, Brendan T; Sheppard, Christine L; Jones, Michael N; Taler, Vanessa

    2016-01-01

    Frequency effects are pervasive in studies of language, with higher frequency words being recognized faster than lower frequency words. However, the exact nature of frequency effects has recently been questioned, with some studies finding that contextual information provides a better fit to lexical decision and naming data than word frequency (Adelman et al., 2006). Recent work has cemented the importance of these results by demonstrating that a measure of the semantic diversity of the contexts that a word occurs in provides a powerful measure to account for variability in word recognition latency (Johns et al., 2012, 2015; Jones et al., 2012). The goal of the current study is to extend this measure to examine bilingualism and aging, where multiple theories use frequency of occurrence of linguistic constructs as central to accounting for empirical results (Gollan et al., 2008; Ramscar et al., 2014). A lexical decision experiment was conducted with four groups of subjects: younger and older monolinguals and bilinguals. Consistent with past results, a semantic diversity variable accounted for the greatest amount of variance in the latency data. In addition, the pattern of fits of semantic diversity across multiple corpora suggests that bilinguals and older adults are more sensitive to semantic diversity information than younger monolinguals.

  3. Automatic air-to-ground target recognition using LWIR FPAs

    NASA Astrophysics Data System (ADS)

    Amadieu, Jean-Louis; Fraysse, Vincent

    1996-06-01

    The theoretical potential of optical sensors in terms of geometrical resolution makes them the ideal solution for achieving the terminal precision guidance of today's missiles. This paper describes such a sensor, working in the 8 to 12 micrometer spectral domain by using a 64 by 64 IRCCD focal plane array, and whose main mission is to recognize various types of armored vehicles within complex scenes that possibly include other vehicles of similar nature. The target recognition process is based upon a Bayesian approach and can be briefly described as follows: after a classical processing stage that performs the filtering and the multi- thresholding, the target recognition algorithm evaluates a similarity level between the objects, including the target, seen in the IR scene and the 'theoretical' target whose some mean, generic features have been implemented in a database. The surroundings of the target and its orientation in the IR scene are 'a priori' unknown. The similarity level is based on calculation of the Mahalanobis distance between the object features vector and the mean features vector of the model; this calculation involves a covariance matrix which is significant of the errors affecting the measured features and that in particular stem form the limited spatial resolution of the sensor, the detector noise and the sensor- to-target range estimation error. With respect to the sensor hardware, its main opto-mechanical characteristics as well as some electro-optics data are indicates; some examples of target acquisition in complex scenes involving different kinds of IR counter measures are also presented.

  4. Masked priming by misspellings: Word frequency moderates the effects of SOA and prime-target similarity.

    PubMed

    Burt, Jennifer S

    2016-02-01

    University students made lexical decisions to eight- or nine-letter words preceded by masked primes that were the target, an unrelated word, or a typical misspelling of the target. At a stimulus onset asynchrony (SOA) of 47 ms, primes that were misspellings of the target produced a priming benefit for low-, medium-, and high-frequency words, even when the misspelled primes were changed to differ phonologically from their targets. At a longer SOA of 80 ms, misspelled primes facilitated lexical decisions only to medium- and low-frequency targets, and a phonological change attenuated the benefit for medium-frequency targets. The results indicate that orthographic similarity can be preserved over changes in letter position and word length, and that the priming effect of misspelled words at the shorter SOA is orthographically based. Orthographic-priming effects depend on the quality of the orthographic learning of the target word. PMID:26530310

  5. Effects of Suprasegmental Phonological Alternations on Early Word Recognition: Evidence from Tone Sandhi

    PubMed Central

    Wewalaarachchi, Thilanga D.; Singh, Leher

    2016-01-01

    Early language acquisition is potentially complicated by the presence of many sources of variability in the speech signal. A frequent example of variability is phonological alternations, which can lead to context-driven changes in the realization of a word. The aim of the current study was to investigate effects of a highly frequent yet scarcely researched type of suprasegmental phonological alternation – tone Sandhi – on early spoken word recognition. The tone Sandhi rule investigated herein involves a tone change of the first syllable in a disyllabic unit. In accordance with third tone Sandhi, when two dipping tone syllables are juxtaposed in connected speech, the first syllable is dissimilated to a high rising tone. For example, ‘flour mill’ (unaltered pre-Sandhi form [(214) (214)]) undergoes tonal alternation resulting in the altered post-Sandhi form [(35) (214)]. In the current study, preschoolers’ sensitivity to the effects of tone Sandhi when processing familiar words was investigated via a preferential looking paradigm. Words varied in their phonological form: one set of words was labeled with a phonological alternation due to Sandhi (Post Sandhi), one set of words was labeled with an unaltered Sandhi form (Pre Sandhi), one set consisted of non Sandhi words (Correct Pronunciation, and one set were labeled with a tonal alternation not associated with Sandhi rules (Mispronunciation). Post-Sandhi forms and correct pronunciations were associated with visual referents with comparable strength, with only a subtle processing cost observed for post-Sandhi forms in the time course of lexical selection. Likewise, pre-Sandhi forms and true mispronunciations were rejected as labels for visual references with comparable strength, with only subtle differences observed in the time course of lexical selection. Findings are discussed in terms of their impact on prevailing theories of lexical representation. PMID:27199855

  6. Assessing Multimodal Spoken Word-in-Sentence Recognition in Children with Normal Hearing and Children with Cochlear Implants

    ERIC Educational Resources Information Center

    Holt, Rachael Frush; Kirk, Karen Iler; Hay-McCutcheon, Marcia

    2011-01-01

    Purpose: To examine multimodal spoken word-in-sentence recognition in children. Method: Two experiments were undertaken. In Experiment 1, the youngest age with which the multimodal sentence recognition materials could be used was evaluated. In Experiment 2, lexical difficulty and presentation modality effects were examined, along with test-retest…

  7. Novel Blind Recognition Algorithm of Frame Synchronization Words Based on Soft-Decision in Digital Communication Systems.

    PubMed

    Qin, Jiangyi; Huang, Zhiping; Liu, Chunwu; Su, Shaojing; Zhou, Jing

    2015-01-01

    A novel blind recognition algorithm of frame synchronization words is proposed to recognize the frame synchronization words parameters in digital communication systems. In this paper, a blind recognition method of frame synchronization words based on the hard-decision is deduced in detail. And the standards of parameter recognition are given. Comparing with the blind recognition based on the hard-decision, utilizing the soft-decision can improve the accuracy of blind recognition. Therefore, combining with the characteristics of Quadrature Phase Shift Keying (QPSK) signal, an improved blind recognition algorithm based on the soft-decision is proposed. Meanwhile, the improved algorithm can be extended to other signal modulation forms. Then, the complete blind recognition steps of the hard-decision algorithm and the soft-decision algorithm are given in detail. Finally, the simulation results show that both the hard-decision algorithm and the soft-decision algorithm can recognize the parameters of frame synchronization words blindly. What's more, the improved algorithm can enhance the accuracy of blind recognition obviously.

  8. Novel Blind Recognition Algorithm of Frame Synchronization Words Based on Soft-Decision in Digital Communication Systems

    PubMed Central

    Qin, Jiangyi; Huang, Zhiping; Liu, Chunwu; Su, Shaojing; Zhou, Jing

    2015-01-01

    A novel blind recognition algorithm of frame synchronization words is proposed to recognize the frame synchronization words parameters in digital communication systems. In this paper, a blind recognition method of frame synchronization words based on the hard-decision is deduced in detail. And the standards of parameter recognition are given. Comparing with the blind recognition based on the hard-decision, utilizing the soft-decision can improve the accuracy of blind recognition. Therefore, combining with the characteristics of Quadrature Phase Shift Keying (QPSK) signal, an improved blind recognition algorithm based on the soft-decision is proposed. Meanwhile, the improved algorithm can be extended to other signal modulation forms. Then, the complete blind recognition steps of the hard-decision algorithm and the soft-decision algorithm are given in detail. Finally, the simulation results show that both the hard-decision algorithm and the soft-decision algorithm can recognize the parameters of frame synchronization words blindly. What’s more, the improved algorithm can enhance the accuracy of blind recognition obviously. PMID:26154439

  9. Re-evaluating split-fovea processing in word recognition: effects of word length during monocular viewing.

    PubMed

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

    2010-01-01

    Several studies have claimed that, when fixating a word, a precise split in foveal processing causes all letters to the left and right of fixation to project to different, contralateral hemispheres (split-fovea theory--SFT). In support of this claim, Lavidor et al. (2001; hereafter LES&B) reported that lexical decisions were affected by the number of letters to the left of fixation but not the right, and that this indicates a functional division in hemispheric processing at the point of fixation. Jordan, Paterson, and Stachurski (Cortex, 2009; hereafter JP&S) re-evaluated these claims over 3 experiments using LES&B's original stimuli and procedures and found no support for the findings of LES&B. Following LES&B, JP&S presented stimuli binocularly (i.e., as in normal viewing). However, this procedure has its own complications for SFT (and for assessing the validity of the theory) because the two eyes often do not fixate the same location. Consequently, we report two further experiments which used an eye-tracker to ensure fixation accuracy and monocular viewing to eliminate influences of fixation disparity. Experiment 1 used the same-sized typeface as JP&S, and Experiment 2 used a larger typeface to approximate normal reading size. In line with the findings of JP&S, neither experiment could replicate the findings of LES&B and both experiments showed simply that word recognition was easier when fixations were made towards the beginning of words. Thus, after a total of 5 separate experiments, using binocular and monocular viewing conditions and stimuli presented in a range of sizes, none of these experiments has been able to replicate the findings of LES&B or provide any evidence for a functional division in hemispheric processing at the point of fixation.

  10. Re-evaluating split-fovea processing in word recognition: a critical assessment of recent research.

    PubMed

    Jordan, Timothy R; Paterson, Kevin B

    2009-10-01

    In recent years, some researchers have proposed that a fundamental component of the word recognition process is that each fovea is divided precisely at its vertical midline and that information either side of this midline projects to different, contralateral hemispheres. Thus, when a word is fixated, all letters to the left of the point of fixation project only to the right hemisphere whereas all letters to the right of the point of fixation project only to the left hemisphere. An informed assessment of research in this area requires an accurate understanding of the nature of the evidence and arguments that have been used to develop this "split-fovea theory" of word recognition (SFT). The purpose of this article is to facilitate this understanding by assessing recent published support for SFT. In particular, we assess (i) the precision with which experiments have been conducted, (ii) the assumptions made about human visual ability, and (iii) the accuracy with which earlier research has been reported. The assessment reveals shortcomings and errors that are likely to impact on an accurate understanding of research in this area and, therefore, on an accurate understanding of the viability of SFT.

  11. Embedded knowledge-based system for automatic target recognition

    NASA Astrophysics Data System (ADS)

    Aboutalib, A. O.

    1990-10-01

    The development of a reliable Automatic Target Recognition (ATE) system is considered a very critical and challenging problem. Existing ATE Systems have inherent limitations in terms of recognition performance and the ability to learn and adapt. Artificial Intelligence Techniques have the potential to improve the performance of ATh Systems. In this paper, we presented a novel Knowledge-Engineering tool, termed, the Automatic Reasoning Process (ARP) , that can be used to automatically develop and maintain a Knowledge-Base (K-B) for the ATR Systems. In its learning mode, the ARP utilizes Learning samples to automatically develop the ATR K-B, which consists of minimum size sets of necessary and sufficient conditions for each target class. In its operational mode, the ARP infers the target class from sensor data using the ATh K-B System. The ARP also has the capability to reason under uncertainty, and can support both statistical and model-based approaches for ATR development. The capabilities of the ARP are compared and contrasted to those of another Knowledge-Engineering tool, termed, the Automatic Rule Induction (ARI) which is based on maximizing the mutual information. The AR? has been implemented in LISP on a VAX-GPX workstation.

  12. Rate of forgetting in amnesia: II. Recall and recognition of word lists at different levels of organization.

    PubMed

    Isaac, C L; Mayes, A R

    1999-07-01

    Amnesic rate of decline of free recall, cued recall, and recognition of word lists with different levels of organization was investigated in 2 experiments. In Experiment 1, it was found that amnesic free recall of semantically related word lists declined at an accelerated rate, whereas free recall of lists of unrelated words declined at a normal rate. Cued recall and recognition performance of both kinds of word lists appeared to decline at a normal rate. In Experiment 2, the results of the free-recall and recognition conditions were replicated using an improved experimental design. The observed amnesic forgetting pattern is interpreted as arising from an impairment in consolidation of long-term memory for complex associations between 2 or more items and their study context that is caused by extended hippocampal system lesions. PMID:10439503

  13. Infrared target recognition based on improved joint local ternary pattern

    NASA Astrophysics Data System (ADS)

    Sun, Junding; Wu, Xiaosheng

    2016-05-01

    This paper presents a simple, efficient, yet robust approach, named joint orthogonal combination of local ternary pattern, for automatic forward-looking infrared target recognition. It gives more advantages to describe the macroscopic textures and microscopic textures by fusing variety of scales than the traditional LBP-based methods. In addition, it can effectively reduce the feature dimensionality. Further, the rotation invariant and uniform scheme, the robust LTP, and soft concave-convex partition are introduced to enhance its discriminative power. Experimental results demonstrate that the proposed method can achieve competitive results compared with the state-of-the-art methods.

  14. The Effects of Word Frequency and Similarity on Recognition Judgments: The Role of Recollection

    ERIC Educational Resources Information Center

    Park, Heekyeong; Reder, Lynne M.; Dickison, Daniel

    2005-01-01

    K. J. Malmberg, J. Holden, and R. M. Shiffrin (2004) reported more false alarms for low- than high-frequency words when the foils were similar to the targets. According to the source of activation confusion (SAC) model of memory, that pattern is based on recollection of an underspecified episodic trace rather than the error-prone familiarity…

  15. Speech Reductions Change the Dynamics of Competition during Spoken Word Recognition

    ERIC Educational Resources Information Center

    Brouwer, Susanne; Mitterer, Holger; Huettig, Falk

    2012-01-01

    Three eye-tracking experiments investigated how phonological reductions (e.g., "puter" for "computer") modulate phonological competition. Participants listened to sentences extracted from a spontaneous speech corpus and saw four printed words: a target (e.g., "computer"), a competitor similar to the canonical form (e.g., "companion"), one similar…

  16. [The influence of visualization of orthography on the recognition of written words].

    PubMed

    Mathey, S

    2001-03-01

    This paper reviews the main research that has been conducted on the role of orthographic neighbourhood in visual word recognition. We focus here on the traditionally defined neighbourhood, that is corresponding to the set of words of the same length sharing all but one letter with the stimulus. Two major theoretical frameworks, namely the activation verification and the interactive activation models, assume that orthographic neighbours are activated when a written word is presented. Predictions formulated by both models for words and pseudowords on the effects of neighbourhood size (N), neighbourhood frequency (NF), and neighbourhood distribution (P), are examined in order to assess the plausibility of serial versus interactive processes. Findings from 27 empirical studies including more than 80 experiments suggest that neighbourhood effects depend on the neighbourhood indexes (N, NF, and P), on the particular tasks (lexical decision, naming, semantic categorization, perceptual identification, and reading), and on the languages (English, French, Spanish, and Dutch) that are used. The results for words can be summarized as follows: (1) In the lexical decision task, the N effect is facilitatory. The NF effect is rather inhibitory, particularly in French and Spanish experiments. The P effect is rather inhibitory in English studies, whereas the P effect for higher frequency neighbours is facilitatory in French. (2) In the perceptual identification task with a single identification response, N and NF effects are inhibitory whatever the language. (3) In the naming task, N and NF effects are facilitatory whatever the language. (4) In the semantic categorization task, an interaction effect between N and NF is found in both English and Spanish. (5) In eye movement studies, the NF effect is inhibitory in both English and French. The issue of lexical versus task-specific processes underlying neighbourhood effects in lexical identification tasks is also examined. On the whole

  17. Visual word recognition in deaf readers: lexicality is modulated by communication mode.

    PubMed

    Barca, Laura; Pezzulo, Giovanni; Castrataro, Marianna; Rinaldi, Pasquale; Caselli, Maria Cristina

    2013-01-01

    Evidence indicates that adequate phonological abilities are necessary to develop proficient reading skills and that later in life phonology also has a role in the covert visual word recognition of expert readers. Impairments of acoustic perception, such as deafness, can lead to atypical phonological representations of written words and letters, which in turn can affect reading proficiency. Here, we report an experiment in which young adults with different levels of acoustic perception (i.e., hearing and deaf individuals) and different modes of communication (i.e., hearing individuals using spoken language, deaf individuals with a preference for sign language, and deaf individuals using the oral modality with less or no competence in sign language) performed a visual lexical decision task, which consisted of categorizing real words and consonant strings. The lexicality effect was restricted to deaf signers who responded faster to real words than consonant strings, showing over-reliance on whole word lexical processing of stimuli. No effect of stimulus type was found in deaf individuals using the oral modality or in hearing individuals. Thus, mode of communication modulates the lexicality effect. This suggests that learning a sign language during development shapes visuo-motor representations of words, which are tuned to the actions used to express them (phono-articulatory movements vs. hand movements) and to associated perceptions. As these visuo-motor representations are elicited during on-line linguistic processing and can overlap with the perceptual-motor processes required to execute the task, they can potentially produce interference or facilitation effects. PMID:23554976

  18. Visual word recognition in deaf readers: lexicality is modulated by communication mode.

    PubMed

    Barca, Laura; Pezzulo, Giovanni; Castrataro, Marianna; Rinaldi, Pasquale; Caselli, Maria Cristina

    2013-01-01

    Evidence indicates that adequate phonological abilities are necessary to develop proficient reading skills and that later in life phonology also has a role in the covert visual word recognition of expert readers. Impairments of acoustic perception, such as deafness, can lead to atypical phonological representations of written words and letters, which in turn can affect reading proficiency. Here, we report an experiment in which young adults with different levels of acoustic perception (i.e., hearing and deaf individuals) and different modes of communication (i.e., hearing individuals using spoken language, deaf individuals with a preference for sign language, and deaf individuals using the oral modality with less or no competence in sign language) performed a visual lexical decision task, which consisted of categorizing real words and consonant strings. The lexicality effect was restricted to deaf signers who responded faster to real words than consonant strings, showing over-reliance on whole word lexical processing of stimuli. No effect of stimulus type was found in deaf individuals using the oral modality or in hearing individuals. Thus, mode of communication modulates the lexicality effect. This suggests that learning a sign language during development shapes visuo-motor representations of words, which are tuned to the actions used to express them (phono-articulatory movements vs. hand movements) and to associated perceptions. As these visuo-motor representations are elicited during on-line linguistic processing and can overlap with the perceptual-motor processes required to execute the task, they can potentially produce interference or facilitation effects.

  19. Visual Word Recognition in Deaf Readers: Lexicality Is Modulated by Communication Mode

    PubMed Central

    Barca, Laura; Pezzulo, Giovanni; Castrataro, Marianna; Rinaldi, Pasquale; Caselli, Maria Cristina

    2013-01-01

    Evidence indicates that adequate phonological abilities are necessary to develop proficient reading skills and that later in life phonology also has a role in the covert visual word recognition of expert readers. Impairments of acoustic perception, such as deafness, can lead to atypical phonological representations of written words and letters, which in turn can affect reading proficiency. Here, we report an experiment in which young adults with different levels of acoustic perception (i.e., hearing and deaf individuals) and different modes of communication (i.e., hearing individuals using spoken language, deaf individuals with a preference for sign language, and deaf individuals using the oral modality with less or no competence in sign language) performed a visual lexical decision task, which consisted of categorizing real words and consonant strings. The lexicality effect was restricted to deaf signers who responded faster to real words than consonant strings, showing over-reliance on whole word lexical processing of stimuli. No effect of stimulus type was found in deaf individuals using the oral modality or in hearing individuals. Thus, mode of communication modulates the lexicality effect. This suggests that learning a sign language during development shapes visuo-motor representations of words, which are tuned to the actions used to express them (phono-articulatory movements vs. hand movements) and to associated perceptions. As these visuo-motor representations are elicited during on-line linguistic processing and can overlap with the perceptual-motor processes required to execute the task, they can potentially produce interference or facilitation effects. PMID:23554976

  20. Reading as Active Sensing: A Computational Model of Gaze Planning in Word Recognition

    PubMed Central

    Ferro, Marcello; Ognibene, Dimitri; Pezzulo, Giovanni; Pirrelli, Vito

    2010-01-01

    We offer a computational model of gaze planning during reading that consists of two main components: a lexical representation network, acquiring lexical representations from input texts (a subset of the Italian CHILDES database), and a gaze planner, designed to recognize written words by mapping strings of characters onto lexical representations. The model implements an active sensing strategy that selects which characters of the input string are to be fixated, depending on the predictions dynamically made by the lexical representation network. We analyze the developmental trajectory of the system in performing the word recognition task as a function of both increasing lexical competence, and correspondingly increasing lexical prediction ability. We conclude by discussing how our approach can be scaled up in the context of an active sensing strategy applied to a robotic setting. PMID:20577589

  1. Reading as active sensing: a computational model of gaze planning in word recognition.

    PubMed

    Ferro, Marcello; Ognibene, Dimitri; Pezzulo, Giovanni; Pirrelli, Vito

    2010-01-01

    WE OFFER A COMPUTATIONAL MODEL OF GAZE PLANNING DURING READING THAT CONSISTS OF TWO MAIN COMPONENTS: a lexical representation network, acquiring lexical representations from input texts (a subset of the Italian CHILDES database), and a gaze planner, designed to recognize written words by mapping strings of characters onto lexical representations. The model implements an active sensing strategy that selects which characters of the input string are to be fixated, depending on the predictions dynamically made by the lexical representation network. We analyze the developmental trajectory of the system in performing the word recognition task as a function of both increasing lexical competence, and correspondingly increasing lexical prediction ability. We conclude by discussing how our approach can be scaled up in the context of an active sensing strategy applied to a robotic setting.

  2. Recognition of inflected words in a morphologically limited language: frequency effects in monolinguals and bilinguals.

    PubMed

    Lehtonen, Minna; Niska, Helge; Wande, Erling; Niemi, Jussi; Laine, Matti

    2006-03-01

    The effect of word frequency on the processing of monomorphemic vs. inflected words was investigated in a morphologically relatively limited language, Swedish, with two participant groups: early Finnish-Swedish bilinguals and Swedish monolinguals. The visual lexical decision results of the monolinguals suggest morphological decomposition with low-frequency inflected nouns, while with medium- and high-frequency inflections, full-form processing was apparently employed. The bilinguals demonstrated a similar pattern. The results suggest that morpheme-based recognition is employed even in a morphologically limited language when the inflectional forms occur rarely. With more frequent inflectional forms, full-form representations have developed for both mono- and bilingual speakers. In a comparable study employing a morphologically rich language, Finnish, Lehtonen and Laine (2003, Bilingualism: Language and Cognition, 6, 213-225) observed full-form access only at the high-frequency range and only for monolinguals. These differences suggest that besides word frequency and language background, the morphological richness of a language affects the processing mode employed with polymorphemic words.

  3. Does richness lose its luster? Effects of extensive practice on semantic richness in visual word recognition

    PubMed Central

    Hargreaves, Ian S.; Pexman, Penny M.

    2012-01-01

    Previous studies have reported facilitatory effects of semantic richness on word recognition (e.g., Yap et al., 2012). These effects suggest that word meaning is an important contributor to lexical decision task (LDT) performance, but what are the effects of repeated LDT practice on these semantic contributions? The current study utilized data from the British Lexicon Project (BLP) in which 78 participants made lexical decision judgments for 28,730 words over 16 h. We used linear mixed effects to detect practice-driven changes in the explanatory variance accounted for by a set of lexical predictors that included numerous indices of relative semantic richness, including imageability, the number of senses and average radius of co-occurrence (ARC). Results showed that practice was associated with decreasing effects of predictors such as word frequency and imageability. In contrast, ARC effects were only slightly diminished with repeated practice, and effects of the number of senses and the age of acquisition were unaffected by practice. We interpret our results within a framework in which variables may dynamically influence lexical processing and the post-lexical decision making mechanisms that also contribute to LDT performance. PMID:22912610

  4. Differences in word recognition between early bilinguals and monolinguals: behavioral and ERP evidence.

    PubMed

    Lehtonen, Minna; Hultén, Annika; Rodríguez-Fornells, Antoni; Cunillera, Toni; Tuomainen, Jyrki; Laine, Matti

    2012-06-01

    We investigated the behavioral and brain responses (ERPs) of bilingual word recognition to three fundamental psycholinguistic factors, frequency, morphology, and lexicality, in early bilinguals vs. monolinguals. Earlier behavioral studies have reported larger frequency effects in bilinguals' nondominant vs. dominant language and in some studies also when compared to corresponding monolinguals. In ERPs, language processing differences between bilinguals vs. monolinguals have typically been found in the N400 component. In the present study, highly proficient Finnish-Swedish bilinguals who had acquired both languages during childhood were compared to Finnish monolinguals during a visual lexical decision task and simultaneous ERP recordings. Behaviorally, we found that the response latencies were overall longer in bilinguals than monolinguals, and that the effects for all three factors, frequency, morphology, and lexicality were also larger in bilinguals even though they had acquired both languages early and were highly proficient in them. In line with this, the N400 effects induced by frequency, morphology, and lexicality were larger for bilinguals than monolinguals. Furthermore, the ERP results also suggest that while most inflected Finnish words are decomposed into stem and suffix, only monolinguals have encountered high frequency inflected word forms often enough to develop full-form representations for them. Larger behavioral and neural effects in bilinguals in these factors likely reflect lower amount of exposure to words compared to monolinguals, as the language input of bilinguals is divided between two languages.

  5. Code-Switching Effects in Bilingual Word Recognition: A Masked Priming Study with Event-Related Potentials

    ERIC Educational Resources Information Center

    Chauncey, Krysta; Grainger, Jonathan; Holcomb, Phillip J.

    2008-01-01

    Two experiments tested language switching effects with bilingual participants in a priming paradigm with masked primes (duration of 50ms in Experiment 1 and 100ms in Experiment 2). Participants had to monitor target words for animal names, and ERPs were recorded to critical (non-animal) words in L1 and L2 primed by unrelated words from the same or…

  6. Unconscious Congruency Priming from Unpracticed Words Is Modulated by Prime-Target Semantic Relatedness

    ERIC Educational Resources Information Center

    Ortells, Juan J.; Mari-Beffa, Paloma; Plaza-Ayllon, Vanesa

    2013-01-01

    Participants performed a 2-choice categorization task on visible word targets that were preceded by novel (unpracticed) prime words. The prime words were presented for 33 ms and followed either immediately (Experiments 1-3) or after a variable delay (Experiments 1 and 4) by a pattern mask. Both subjective and objective measures of prime visibility…

  7. Feature Extraction and Selection Strategies for Automated Target Recognition

    NASA Technical Reports Server (NTRS)

    Greene, W. Nicholas; Zhang, Yuhan; Lu, Thomas T.; Chao, Tien-Hsin

    2010-01-01

    Several feature extraction and selection methods for an existing automatic target recognition (ATR) system using JPLs Grayscale Optical Correlator (GOC) and Optimal Trade-Off Maximum Average Correlation Height (OT-MACH) filter were tested using MATLAB. The ATR system is composed of three stages: a cursory region of-interest (ROI) search using the GOC and OT-MACH filter, a feature extraction and selection stage, and a final classification stage. Feature extraction and selection concerns transforming potential target data into more useful forms as well as selecting important subsets of that data which may aide in detection and classification. The strategies tested were built around two popular extraction methods: Principal Component Analysis (PCA) and Independent Component Analysis (ICA). Performance was measured based on the classification accuracy and free-response receiver operating characteristic (FROC) output of a support vector machine(SVM) and a neural net (NN) classifier.

  8. Serial and parallel processing in reading: investigating the effects of parafoveal orthographic information on nonisolated word recognition.

    PubMed

    Dare, Natasha; Shillcock, Richard

    2013-01-01

    We present a novel lexical decision task and three boundary paradigm eye-tracking experiments that clarify the picture of parallel processing in word recognition in context. First, we show that lexical decision is facilitated by associated letter information to the left and right of the word, with no apparent hemispheric specificity. Second, we show that parafoveal preview of a repeat of word n at word n + 1 facilitates reading of word n relative to a control condition with an unrelated word at word n + 1. Third, using a version of the boundary paradigm that allowed for a regressive eye movement, we show no parafoveal "postview" effect on reading word n of repeating word n at word n - 1. Fourth, we repeat the second experiment but compare the effects of parafoveal previews consisting of a repeated word n with a transposed central bigram (e.g., caot for coat) and a substituted central bigram (e.g., ceit for coat), showing the latter to have a deleterious effect on processing word n, thereby demonstrating that the parafoveal preview effect is at least orthographic and not purely visual. PMID:22950804

  9. Tracker-aided adaptive multi-frame recognition of a specific target

    NASA Astrophysics Data System (ADS)

    Mahalanobis, Abhijit

    2016-05-01

    We consider the problem of recognizing a particular target of interest (i.e. the "correct" target) while rejecting other targets and background clutter. In such instances, the probability of recognizing the correct target (PCT) is a suitable metric for assessing the performance of the target recognition algorithm. We present a definition for PCT and illustrate how it differs from conventional metrics for target recognition by means of an example. It is further shown that an adaptive target recognition algorithm, which relies on track position to obtain multiple looks at the target, can significantly improve PCT while reducing the track uncertainty.

  10. Novel automatic target recognition approach for multispectral data

    NASA Astrophysics Data System (ADS)

    Salazar, Jose S.; Koch, Mark W.; Yocky, David A.

    2002-11-01

    Automating the detection and identification of significant threats using multispectral (MS) imagery is a critical issue in remote sensing. Unlike previous multispectral target recognition approaches, we utilize a three-stage process that not only takes into account the spectral content, but also the spatial information. The first stage applies a matched filter to the calibrated MS data. Here, the matched filter is tuned to the spectral components of a given target and produces an image intensity map of where the best matches occur. The second stage represents a novel detection algorithm, known as the focus of attention (FOA) stage. The FOA performs an initial screening of the data based on intensity and size checks on the matched filter output. Next, using the target's pure components, the third stage performs constrained linear unmixing on MS pixels within the FOA detected regions. Knowledge sources derived from this process are combined using a sequential probability ratio test (SPRT). The SPRT can fuse contaminated, uncertain and disparate information from multiple sources. We demonstrate our approach on identifying a specific target using actual data collected in ideal conditions and also use approximately 35 square kilometers of urban clutter as false alarm data.

  11. A Corpus-Based Approach for Automatic Thai Unknown Word Recognition Using Boosting Techniques

    NASA Astrophysics Data System (ADS)

    Techo, Jakkrit; Nattee, Cholwich; Theeramunkong, Thanaruk

    While classification techniques can be applied for automatic unknown word recognition in a language without word boundary, it faces with the problem of unbalanced datasets where the number of positive unknown word candidates is dominantly smaller than that of negative candidates. To solve this problem, this paper presents a corpus-based approach that introduces a so-called group-based ranking evaluation technique into ensemble learning in order to generate a sequence of classification models that later collaborate to select the most probable unknown word from multiple candidates. Given a classification model, the group-based ranking evaluation (GRE) is applied to construct a training dataset for learning the succeeding model, by weighing each of its candidates according to their ranks and correctness when the candidates of an unknown word are considered as one group. A number of experiments have been conducted on a large Thai medical text to evaluate performance of the proposed group-based ranking evaluation approach, namely V-GRE, compared to the conventional naïve Bayes classifier and our vanilla version without ensemble learning. As the result, the proposed method achieves an accuracy of 90.93±0.50% when the first rank is selected while it gains 97.26±0.26% when the top-ten candidates are considered, that is 8.45% and 6.79% improvement over the conventional record-based naïve Bayes classifier and the vanilla version. Another result on applying only best features show 93.93±0.22% and up to 98.85±0.15% accuracy for top-1 and top-10, respectively. They are 3.97% and 9.78% improvement over naive Bayes and the vanilla version. Finally, an error analysis is given.

  12. Semantic contribution to verbal short-term memory: are pleasant words easier to remember than neutral words in serial recall and serial recognition?

    PubMed

    Monnier, Catherine; Syssau, Arielle

    2008-01-01

    In the four experiments reported here, we examined the role of word pleasantness on immediate serial recall and immediate serial recognition. In Experiment 1, we compared verbal serial recall of pleasant and neutral words, using a limited set of items. In Experiment 2, we replicated Experiment 1 with an open set of words (i.e., new items were used on every trial). In Experiments 3 and 4, we assessed immediate serial recognition of pleasant and neutral words, using item sets from Experiments 1 and 2. Pleasantness was found to have a facilitation effect on both immediate serial recall and immediate serial recognition. This study supplies some new supporting arguments in favor of a semantic contribution to verbal short-term memory performance. The pleasantness effect observed in immediate serial recognition showed that, contrary to a number of earlier findings, performance on this task can also turn out to be dependent on semantic factors. The results are discussed in relation to nonlinguistic and psycholinguistic models of short-term memory.

  13. Effect of response context and masker type on word recognition in school-age children and adults.

    PubMed

    Buss, Emily; Leibold, Lori J; Hall, Joseph W

    2016-08-01

    In adults, masked speech recognition improves with the provision of a closed set of response alternatives. The present study evaluated whether school-age children (5-13 years) benefit to the same extent as adults from a forced-choice context, and whether this effect depends on masker type. Experiment 1 compared masked speech reception thresholds for disyllabic words in either an open-set or a four-alternative forced-choice (4AFC) task. Maskers were speech-shaped noise or two-talker speech. Experiment 2 compared masked speech reception thresholds for monosyllabic words in two 4AFC tasks, one in which the target and foils were phonetically similar and one in which they were dissimilar. Maskers were speech-shaped noise, amplitude-modulated noise, or two-talker speech. For both experiments, it was predicted that children would not benefit from the information provided by the 4AFC context to the same degree as adults, particularly when the masker was complex (two-talker) or when audible speech cues were temporally sparse (modulated-noise). Results indicate that young children do benefit from a 4AFC context to the same extent as adults in speech-shaped noise and amplitude-modulated noise, but the benefit of context increases with listener age for the two-talker speech masker. PMID:27586729

  14. Does viotin activate violin more than viocin? On the use of visual cues during visual-word recognition.

    PubMed

    Perea, Manuel; Panadero, Victoria

    2014-01-01

    The vast majority of neural and computational models of visual-word recognition assume that lexical access is achieved via the activation of abstract letter identities. Thus, a word's overall shape should play no role in this process. In the present lexical decision experiment, we compared word-like pseudowords like viotín (same shape as its base word: violín) vs. viocín (different shape) in mature (college-aged skilled readers), immature (normally reading children), and immature/impaired (young readers with developmental dyslexia) word-recognition systems. Results revealed similar response times (and error rates) to consistent-shape and inconsistent-shape pseudowords for both adult skilled readers and normally reading children - this is consistent with current models of visual-word recognition. In contrast, young readers with developmental dyslexia made significantly more errors to viotín-like pseudowords than to viocín-like pseudowords. Thus, unlike normally reading children, young readers with developmental dyslexia are sensitive to a word's visual cues, presumably because of poor letter representations.

  15. Does viotin activate violin more than viocin? On the use of visual cues during visual-word recognition.

    PubMed

    Perea, Manuel; Panadero, Victoria

    2014-01-01

    The vast majority of neural and computational models of visual-word recognition assume that lexical access is achieved via the activation of abstract letter identities. Thus, a word's overall shape should play no role in this process. In the present lexical decision experiment, we compared word-like pseudowords like viotín (same shape as its base word: violín) vs. viocín (different shape) in mature (college-aged skilled readers), immature (normally reading children), and immature/impaired (young readers with developmental dyslexia) word-recognition systems. Results revealed similar response times (and error rates) to consistent-shape and inconsistent-shape pseudowords for both adult skilled readers and normally reading children - this is consistent with current models of visual-word recognition. In contrast, young readers with developmental dyslexia made significantly more errors to viotín-like pseudowords than to viocín-like pseudowords. Thus, unlike normally reading children, young readers with developmental dyslexia are sensitive to a word's visual cues, presumably because of poor letter representations. PMID:23948388

  16. The activation of segmental and tonal information in visual word recognition.

    PubMed

    Li, Chuchu; Lin, Candise Y; Wang, Min; Jiang, Nan

    2013-08-01

    Mandarin Chinese has a logographic script in which graphemes map onto syllables and morphemes. It is not clear whether Chinese readers activate phonological information during lexical access, although phonological information is not explicitly represented in Chinese orthography. In the present study, we examined the activation of phonological information, including segmental and tonal information in Chinese visual word recognition, using the Stroop paradigm. Native Mandarin speakers named the presentation color of Chinese characters in Mandarin. The visual stimuli were divided into five types: color characters (e.g., , hong2, "red"), homophones of the color characters (S+T+; e.g., , hong2, "flood"), different-tone homophones (S+T-; e.g., , hong1, "boom"), characters that shared the same tone but differed in segments with the color characters (S-T+; e.g., , ping2, "bottle"), and neutral characters (S-T-; e.g., , qian1, "leading through"). Classic Stroop facilitation was shown in all color-congruent trials, and interference was shown in the incongruent trials. Furthermore, the Stroop effect was stronger for S+T- than for S-T+ trials, and was similar between S+T+ and S+T- trials. These findings suggested that both tonal and segmental forms of information play roles in lexical constraints; however, segmental information has more weight than tonal information. We proposed a revised visual word recognition model in which the functions of both segmental and suprasegmental types of information and their relative weights are taken into account. PMID:23400856

  17. Word recognition deficits in German: more evidence from a representative sample.

    PubMed

    Landerl, K

    2001-01-01

    In a representative sample of German speaking dyslexic children, earlier findings on dyslexia in the highly consistent orthography of German were confirmed. In a sample of 78 dyslexic 3rd graders selected on the basis of their poor word recognition skills, reading accuracy for both words and non-words was deficient but high in absolute terms. This indicates that the highly consistent grapheme-phoneme correspondences of German orthography in combination with the straightforward phonics teaching approach, which is usually applied in Austrian primary schools, allows even dyslexic children to acquire the process of phonological decoding. The central reading problem was extremely slow speed. Poor performance on a reading comprehension test was at least partly due to slow reading speed as well. Dyslexic children's spelling development was also severely delayed. The number of phonologically incorrect spellings was low; however, dyslexic children quite often produced spellings that are orthographically incorrect, indicating that they have not yet been able to develop an extensive and easily accessible orthographic lexicon. The most prominent cognitive deficit was reduced rapid naming speed closely followed by deficits in phonological awareness. Deficits in phonological memory were also evident (but mild) showing that despite marked differences in findings on reading and spelling skills of English dyslexic children, the underlying causes are very similar. The present sample of dyslexic children showed deficits in visual processing speed in addition to their linguistic deficits. However, this deficit in visual processing speed did not seem causally related to the children's reading and spelling deficits.

  18. Assessing the performance of a covert automatic target recognition algorithm

    NASA Astrophysics Data System (ADS)

    Ehrman, Lisa M.; Lanterman, Aaron D.

    2005-05-01

    Passive radar systems exploit illuminators of opportunity, such as TV and FM radio, to illuminate potential targets. Doing so allows them to operate covertly and inexpensively. Our research seeks to enhance passive radar systems by adding automatic target recognition (ATR) capabilities. In previous papers we proposed conducting ATR by comparing the radar cross section (RCS) of aircraft detected by a passive radar system to the precomputed RCS of aircraft in the target class. To effectively model the low-frequency setting, the comparison is made via a Rician likelihood model. Monte Carlo simulations indicate that the approach is viable. This paper builds on that work by developing a method for quickly assessing the potential performance of the ATR algorithm without using exhaustive Monte Carlo trials. This method exploits the relation between the probability of error in a binary hypothesis test under the Bayesian framework to the Chernoff information. Since the data are well-modeled as Rician, we begin by deriving a closed-form approximation for the Chernoff information between two Rician densities. This leads to an approximation for the probability of error in the classification algorithm that is a function of the number of available measurements. We conclude with an application that would be particularly cumbersome to accomplish via Monte Carlo trials, but that can be quickly addressed using the Chernoff information approach. This application evaluates the length of time that an aircraft must be tracked before the probability of error in the ATR algorithm drops below a desired threshold.

  19. Multi-Stage System for Automatic Target Recognition

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin; Lu, Thomas T.; Ye, David; Edens, Weston; Johnson, Oliver

    2010-01-01

    A multi-stage automated target recognition (ATR) system has been designed to perform computer vision tasks with adequate proficiency in mimicking human vision. The system is able to detect, identify, and track targets of interest. Potential regions of interest (ROIs) are first identified by the detection stage using an Optimum Trade-off Maximum Average Correlation Height (OT-MACH) filter combined with a wavelet transform. False positives are then eliminated by the verification stage using feature extraction methods in conjunction with neural networks. Feature extraction transforms the ROIs using filtering and binning algorithms to create feature vectors. A feedforward back-propagation neural network (NN) is then trained to classify each feature vector and to remove false positives. The system parameter optimizations process has been developed to adapt to various targets and datasets. The objective was to design an efficient computer vision system that can learn to detect multiple targets in large images with unknown backgrounds. Because the target size is small relative to the image size in this problem, there are many regions of the image that could potentially contain the target. A cursory analysis of every region can be computationally efficient, but may yield too many false positives. On the other hand, a detailed analysis of every region can yield better results, but may be computationally inefficient. The multi-stage ATR system was designed to achieve an optimal balance between accuracy and computational efficiency by incorporating both models. The detection stage first identifies potential ROIs where the target may be present by performing a fast Fourier domain OT-MACH filter-based correlation. Because threshold for this stage is chosen with the goal of detecting all true positives, a number of false positives are also detected as ROIs. The verification stage then transforms the regions of interest into feature space, and eliminates false positives using an

  20. Target detection and recognition improvements by use of spatiotemporal fusion.

    PubMed

    Chen, Hai-Wen; Sutha, Surachai; Olson, Teresa

    2004-01-10

    We developed spatiotemporal fusion techniques for improving target detection and automatic target recognition. We also investigated real IR (infrared) sensor clutter noise. The sensor noise was collected by an IR (256 x 256) sensor looking at various scenes (trees, grass, roads, buildings, etc.). More than 95% of the sensor pixels showed near-stationary sensor clutter noise that was uncorrelated between pixels as well as across time frames. However, in a few pixels (covering the grass near the road) the sensor noise showed nonstationary properties (with increasing or decreasing mean across time frames). The natural noise extracted from the IR sensor, as well as the computer-generated noise with Gaussian and Rayleigh distributions, was used to test and compare different spatiotemporal fusion strategies. Finally, we proposed two advanced detection schemes: the double-thresholding the reverse-thresholding techniques. These techniques may be applied to complicated clutter situations (e.g., very-high clutter or nonstationary clutter situations) where the traditional constant-false-alarm-ratio technique may fail. PMID:14735959

  1. A proposal for combining mapping, localization and target recognition

    NASA Astrophysics Data System (ADS)

    Grönwall, Christina; Hendeby, Gustaf; Sinivaara, Kristian

    2015-10-01

    Simultaneous localization and mapping (SLAM) is a well-known positioning approach in GPS-denied environments such as urban canyons and inside buildings. Autonomous/aided target detection and recognition (ATR) is commonly used in military application to detect threats and targets in outdoor environments. This papers present approaches to combine SLAM with ATR in ways that compensate for the drawbacks in each method. The methods use physical objects that are recognizable by ATR as unambiguous features in SLAM, while SLAM provides the ATR with better position estimates. Landmarks in the form of 3D point features based on normal aligned radial features (NARF) are used in conjunction with identified objects and 3D object models that replace landmarks when possible. This leads to a more compact map representation with fewer landmarks, which partly compensates for the introduced cost of the ATR. We analyze three approaches to combine SLAM and 3D-data; point-point matching ignoring NARF features, point-point matching using the set of points that are selected by NARF feature analysis, and matching of NARF features using nearest neighbor analysis. The first two approaches are is similar to the common iterative closest point (ICP). We propose an algorithm that combines EKF-SLAM and ATR based on rectangle estimation. The intended application is to improve the positioning of a first responder moving through an indoor environment, where the map offers localization and simultaneously helps locate people, furniture and potentially dangerous objects such as gas canisters.

  2. Identifiable Orthographically Similar Word Primes Interfere in Visual Word Identification

    ERIC Educational Resources Information Center

    Burt, Jennifer S.

    2009-01-01

    University students participated in five experiments concerning the effects of unmasked, orthographically similar, primes on visual word recognition in the lexical decision task (LDT) and naming tasks. The modal prime-target stimulus onset asynchrony (SOA) was 350 ms. When primes were words that were orthographic neighbors of the targets, and…

  3. Spoken word recognition in early childhood: Comparative effects of vowel, consonant and lexical tone variation.

    PubMed

    Singh, Leher; Goh, Hwee Hwee; Wewalaarachchi, Thilanga D

    2015-09-01

    The majority of the world's languages exploit consonants, vowels and lexical tones to contrast the meanings of individual words. However, the majority of experimental research on early language development focuses on consonant-vowel languages. In the present study, the role of consonants, vowels and lexical tones in emergent word knowledge are directly compared in toddlers (2.5-3.5 years) and preschoolers (4-5 years) who were bilingual native learners of a consonant-vowel-tone language (Mandarin Chinese). Using a preferential looking paradigm, participants were presented with correct pronunciations and consonantal, vowel, and tonal variations of known words. Responses to each type of variation were assessed via gaze fixations to a visual target. When their labels were correctly pronounced, visual targets were reliably identified at both age groups. However, in toddlers, there was a high degree of sensitivity to mispronunciations due to variation in lexical tones relative to those due to consonants and vowels. This pattern was reversed in preschoolers, who were more sensitive to consonant and vowel variation than to tone variation. Findings are discussed in terms of properties of tones, vowels and consonants and the respective role of each source of variation in tone languages.

  4. A Pathogenic Nematode Targets Recognition Proteins to Avoid Insect Defenses

    PubMed Central

    Toubarro, Duarte; Avila, Mónica Martinez; Montiel, Rafael; Simões, Nelson

    2013-01-01

    Steinernemacarpocapsae is a nematode pathogenic in a wide variety of insect species. The great pathogenicity of this nematode has been ascribed to its ability to overcome the host immune response; however, little is known about the mechanisms involved in this process. The analysis of an expressed sequence tags (EST) library in the nematode during the infective phase was performed and a highly abundant contig homologous to serine protease inhibitors was identified. In this work, we show that this contig is part of a 641-bp cDNA that encodes a BPTI-Kunitz family inhibitor (Sc-KU-4), which is up-regulated in the parasite during invasion and installation. Recombinant Sc-KU-4 protein was produced in Escherichia coli and shown to inhibit chymotrypsin and elastase activities in a dose-dependent manner by a competitive mechanism with Ki values of 1.8 nM and 2.6 nM, respectively. Sc-KU-4 also inhibited trypsin and thrombin activities to a lesser extent. Studies of the mode of action of Sc-KU-4 and its effects on insect defenses suggest that although Sc-KU-4 did not inhibit the activation of hemocytes or the formation of clotting fibers, it did inhibit hemocyte aggregation and the entrapment of foreign particles by fibers. Moreover, Sc-KU-4 avoided encapsulation and the deposition of clotting materials, which usually occurs in response to foreign particles. We show by protein-protein interaction that Sc-KU-4 targets recognition proteins of insect immune system such as masquerade-like and serine protease-like homologs. The interaction of Sc-KU-4 with these proteins explains the ability of the nematode to overcome host reactions and its large pathogenic spectrum, once these immune proteins are well conserved in insects. The discovery of this inhibitor targeting insect recognition proteins opens new avenues for the development of S. carpocapsae as a biological control agent and provides a new tool to study host-pathogen interactions. PMID:24098715

  5. A pathogenic nematode targets recognition proteins to avoid insect defenses.

    PubMed

    Toubarro, Duarte; Avila, Mónica Martinez; Montiel, Rafael; Simões, Nelson

    2013-01-01

    Steinernemacarpocapsae is a nematode pathogenic in a wide variety of insect species. The great pathogenicity of this nematode has been ascribed to its ability to overcome the host immune response; however, little is known about the mechanisms involved in this process. The analysis of an expressed sequence tags (EST) library in the nematode during the infective phase was performed and a highly abundant contig homologous to serine protease inhibitors was identified. In this work, we show that this contig is part of a 641-bp cDNA that encodes a BPTI-Kunitz family inhibitor (Sc-KU-4), which is up-regulated in the parasite during invasion and installation. Recombinant Sc-KU-4 protein was produced in Escherichia coli and shown to inhibit chymotrypsin and elastase activities in a dose-dependent manner by a competitive mechanism with Ki values of 1.8 nM and 2.6 nM, respectively. Sc-KU-4 also inhibited trypsin and thrombin activities to a lesser extent. Studies of the mode of action of Sc-KU-4 and its effects on insect defenses suggest that although Sc-KU-4 did not inhibit the activation of hemocytes or the formation of clotting fibers, it did inhibit hemocyte aggregation and the entrapment of foreign particles by fibers. Moreover, Sc-KU-4 avoided encapsulation and the deposition of clotting materials, which usually occurs in response to foreign particles. We show by protein-protein interaction that Sc-KU-4 targets recognition proteins of insect immune system such as masquerade-like and serine protease-like homologs. The interaction of Sc-KU-4 with these proteins explains the ability of the nematode to overcome host reactions and its large pathogenic spectrum, once these immune proteins are well conserved in insects. The discovery of this inhibitor targeting insect recognition proteins opens new avenues for the development of S. carpocapsae as a biological control agent and provides a new tool to study host-pathogen interactions.

  6. Orthographic Consistency and Word-Frequency Effects in Auditory Word Recognition: New Evidence from Lexical Decision and Rime Detection

    PubMed Central

    Petrova, Ana; Gaskell, M. Gareth; Ferrand, Ludovic

    2011-01-01

    Many studies have repeatedly shown an orthographic consistency effect in the auditory lexical decision task. Words with phonological rimes that could be spelled in multiple ways (i.e., inconsistent words) typically produce longer auditory lexical decision latencies and more errors than do words with rimes that could be spelled in only one way (i.e., consistent words). These results have been extended to different languages and tasks, suggesting that the effect is quite general and robust. Despite this growing body of evidence, some psycholinguists believe that orthographic effects on spoken language are exclusively strategic, post-lexical, or restricted to peculiar (low-frequency) words. In the present study, we manipulated consistency and word-frequency orthogonally in order to explore whether the orthographic consistency effect extends to high-frequency words. Two different tasks were used: lexical decision and rime detection. Both tasks produced reliable consistency effects for both low- and high-frequency words. Furthermore, in Experiment 1 (lexical decision), an interaction revealed a stronger consistency effect for low-frequency words than for high-frequency words, as initially predicted by Ziegler and Ferrand (1998), whereas no interaction was found in Experiment 2 (rime detection). Our results extend previous findings by showing that the orthographic consistency effect is obtained not only for low-frequency words but also for high-frequency words. Furthermore, these effects were also obtained in a rime detection task, which does not require the explicit processing of orthographic structure. Globally, our results suggest that literacy changes the way people process spoken words, even for frequent words. PMID:22025916

  7. A Comparison of Perceptual Motor Skill with Auditory Comprehension as Correlates of Word Recognition, Oral Reading, and Silent Reading.

    ERIC Educational Resources Information Center

    Tillman, Chester E.

    A study was conducted to examine the relationship of perceptual motor skills as measured by the Bender Visual Motor Gestalt Test to word recognition, oral reading, and silent reading. In addition, perceptual motor skill and auditory comprehension were compared as correlates of the three reading variables. Subjects were 60 primary grade students in…

  8. A Not-so-Simple View of Reading: How Oral Vocabulary and Visual-Word Recognition Complicate the Story

    ERIC Educational Resources Information Center

    Ouellette, Gene; Beers, Ashley

    2010-01-01

    The present study sought to clarify the relations amongst serial decoding, irregular word recognition, listening comprehension, facets of oral vocabulary and reading comprehension in two cohorts of children differing in reading level. In the process, the components of the simple view of reading were evaluated. Students in grades 1 (n = 67) and 6…

  9. Computer-Mediated Input, Output and Feedback in the Development of L2 Word Recognition from Speech

    ERIC Educational Resources Information Center

    Matthews, Joshua; Cheng, Junyu; O'Toole, John Mitchell

    2015-01-01

    This paper reports on the impact of computer-mediated input, output and feedback on the development of second language (L2) word recognition from speech (WRS). A quasi-experimental pre-test/treatment/post-test research design was used involving three intact tertiary level English as a Second Language (ESL) classes. Classes were either assigned to…

  10. Morphological Structure Processing during Word Recognition and Its Relationship to Character Reading among Third-Grade Chinese Children

    ERIC Educational Resources Information Center

    Liu, Duo; McBride-Chang, Catherine

    2014-01-01

    In the present study, we explored the characteristics of morphological structure processing during word recognition among third grade Chinese children and its possible relationship with Chinese character reading. By using the modified priming lexical decision paradigm, a significant morphological structure priming effect was found in the subject…

  11. Enhanced Recognition and Recall of New Words in 7- and 12-Year-Olds Following a Period of Offline Consolidation

    ERIC Educational Resources Information Center

    Brown, Helen; Weighall, Anna; Henderson, Lisa M.; Gaskell, M. Gareth

    2012-01-01

    Recent studies of adults have found evidence for consolidation effects in the acquisition of novel words, but little is known about whether such effects are found developmentally. In two experiments, we familiarized children with novel nonwords (e.g., "biscal") and tested their recognition and recall of these items. In Experiment 1, 7-year-olds…

  12. Use of Context in the Word Recognition Process by Adults with a Significant History of Reading Difficulties

    ERIC Educational Resources Information Center

    Corkett, Julie K.; Parrila, Rauno

    2008-01-01

    We examined whether university students who report a significant history of reading difficulties (RD; n=24) differed from university students with no history of reading difficulties (NRD; n=31) in how sentence context affects word recognition. Experiment 1 found no differences in how congruent sentence primes or syntactic manipulations of the…

  13. Lexical Access in Early Stages of Visual Word Processing: A Single-Trial Correlational MEG Study of Heteronym Recognition

    ERIC Educational Resources Information Center

    Solomyak, Olla; Marantz, Alec

    2009-01-01

    We present an MEG study of heteronym recognition, aiming to distinguish between two theories of lexical access: the "early access" theory, which entails that lexical access occurs at early (pre 200 ms) stages of processing, and the "late access" theory, which interprets this early activity as orthographic word-form identification rather than…

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

    ERIC Educational Resources Information Center

    Rispens, Judith; Baker, Anne; Duinmeijer, Iris

    2015-01-01

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

  15. The Effects of Linguistic Context on Word Recognition in Noise by Elderly Listeners Using Spanish Sentence Lists (SSL)

    ERIC Educational Resources Information Center

    Cervera, Teresa; Rosell, Vicente

    2015-01-01

    This study evaluated the effects of the linguistic context on the recognition of words in noise in older listeners using the Spanish Sentence Lists. These sentences were developed based on the approach of the SPIN test for the English language, which contains high and low predictability (HP and LP) sentences. In addition, the relative contribution…

  16. Voiced Initial Consonant Perception Deficits in Older Listeners with Hearing Loss and Good and Poor Word Recognition

    ERIC Educational Resources Information Center

    Phillips, Susan L.; Richter, Scott J.; McPherson, David

    2009-01-01

    Purpose: This study examined differences in voiced consonant-vowel (CV) perception in older listeners with normal hearing and in 2 groups of older listeners with matched hearing losses: those with good and those with poor word recognition scores. Method: Thirty-six participants identified CVs from an 8-item display from the natural voiced initial…

  17. The Influence of Sentence Context and Accented Speech on Lexical Access in Second-Language Auditory Word Recognition

    ERIC Educational Resources Information Center

    Lagrou, Evelyne; Harsuiker, Robert J.; Duyck, Wouter

    2013-01-01

    Until now, research on bilingual auditory word recognition has been scarce, and although most studies agree that lexical access is language-nonselective, there is less consensus with respect to the influence of potentially constraining factors. The present study investigated the influence of three possible constraints. We tested whether language…

  18. Effects of Employing the Text, SRA Decoding Strategies on the Word Recognition for a High School Student with Learning Disabilities

    ERIC Educational Resources Information Center

    Lykken, Alyson; Wakeman, Julie; Neyman, Jennifer; McLaughlin, T. F.; Zumwalt, Kim

    2014-01-01

    An objective of this study was to evaluate the effects of employing the SRA Decoding Strategies text on word recognition for a ninth grade male with a learning disability. The student was enrolled in a high school special education resource room in a large urban school district in the Pacific North west in a direct instruction reading resource…

  19. The Effects of Inter-Letter Spacing in Visual-Word Recognition: Evidence with Young Normal Readers and Developmental Dyslexics

    ERIC Educational Resources Information Center

    Perea, Manuel; Panadero, Victoria; Moret-Tatay, Carmen; Gomez, Pablo

    2012-01-01

    Recent research has demonstrated that slight increases of inter-letter spacing have a positive impact on skilled readers' recognition of visually presented words. In the present study, we examined whether this effect generalises to young normal readers and readers with developmental dyslexia, and whether increased inter-letter spacing affects the…

  20. Hybrid generative-discriminative human action recognition by combining spatiotemporal words with supervised topic models

    NASA Astrophysics Data System (ADS)

    Sun, Hao; Wang, Cheng; Wang, Boliang

    2011-02-01

    We present a hybrid generative-discriminative learning method for human action recognition from video sequences. Our model combines a bag-of-words component with supervised latent topic models. A video sequence is represented as a collection of spatiotemporal words by extracting space-time interest points and describing these points using both shape and motion cues. The supervised latent Dirichlet allocation (sLDA) topic model, which employs discriminative learning using labeled data under a generative framework, is introduced to discover the latent topic structure that is most relevant to action categorization. The proposed algorithm retains most of the desirable properties of generative learning while increasing the classification performance though a discriminative setting. It has also been extended to exploit both labeled data and unlabeled data to learn human actions under a unified framework. We test our algorithm on three challenging data sets: the KTH human motion data set, the Weizmann human action data set, and a ballet data set. Our results are either comparable to or significantly better than previously published results on these data sets and reflect the promise of hybrid generative-discriminative learning approaches.

  1. Deficient morphological processing in adults with developmental dyslexia: another barrier to efficient word recognition?

    PubMed

    Schiff, Rachel; Raveh, Michal

    2007-05-01

    Research on dyslexia has focused on the phonological level of linguistic analysis. Here we extend the investigation of the linguistic competence of individuals with dyslexia to the morphological level of linguistic analysis. We examine whether adult Hebrew readers with dyslexia extract and represent morphemic units similarly to normal readers. Using the priming paradigm in the word fragment completion task, we measured the magnitude of morphological priming and contrasted this effect with the repetition priming effect. Students with normal reading ability showed the typical repetition priming effect. A comparable repetition priming effect was also found for the dyslexic group as a whole. However, when the dyslexics were classified into three subtypes according to their phonological and orthographic decoding skills, repetition priming effects were significant only for the phonological dyslexia subgroup but not for the surface or mixed dyslexia subgroups. Furthermore, students with normal reading ability showed strong morphological priming, comparable in strength to the repetition priming effect. In contrast, the dyslexic readers did not show morphological priming, neither the dyslexia group as a whole, nor any of the subgroups. Our results highlight an additional source for dyslexics' difficulties with word recognition which lie at the level of morphological processing. PMID:17557687

  2. Distinguishing Target From Distractor in Stroop, Picture–Word, and Word–Word Interference Tasks

    PubMed Central

    Schmalz, Xenia; Treccani, Barbara; Mulatti, Claudio

    2015-01-01

    Lexical selection—both during reading aloud and speech production—involves selecting an intended word, while ignoring irrelevant lexical activation. This process has been studied by the use of interference tasks. Examples are the Stroop task, where participants ignore the written color word and name the color of the ink, picture–word interference tasks, where participants name a picture while ignoring a super-imposed written word, or word–word interference (WWI) tasks, where two words are presented and the participants need to respond to only one, based on an pre-determined visual feature (e.g., color, position). Here, we focus on the WWI task: it is theoretically impossible for existing models to explain how the cognitive system can respond to one stimulus and block the other, when they are presented by the same modality (i.e., they are both words). We describe a solution that can explain performance on the WWI task: drawing on the literature on visual attention, we propose that the system creates an object file for each perceived object, which is continuously updated with increasingly complete information about the stimulus, such as the task-relevant visual feature. Such a model can account for performance on all three tasks. PMID:26696927

  3. Activation of p53 Facilitates the Target Search in DNA by Enhancing the Target Recognition Probability.

    PubMed

    Itoh, Yuji; Murata, Agato; Sakamoto, Seiji; Nanatani, Kei; Wada, Takehiko; Takahashi, Satoshi; Kamagata, Kiyoto

    2016-07-17

    Tumor suppressor p53 binds to the target in a genome and regulates the expression of downstream genes. p53 searches for the target by combining three-dimensional diffusion and one-dimensional sliding along the DNA. To examine the regulation mechanism of the target binding, we constructed the pseudo-wild type (pseudo-WT), activated (S392E), and inactive (R248Q) mutants of p53 and observed their target binding in long DNA using single-molecule fluorescence imaging. The pseudo-WT sliding along the DNA showed many pass events over the target and possessed target recognition probability (TRP) of 7±2%. The TRP increased to 18±2% for the activated mutant but decreased to 0% for the inactive mutant. Furthermore, the fraction of the target binding by the one-dimensional sliding among the total binding events increased from 63±9% for the pseudo-WT to 87±2% for the activated mutant. Control of TRP upon activation, as demonstrated here for p53, might be a general activation mechanism of transcription factors.

  4. Attention modulates specificity effects in spoken word recognition: Challenges to the time-course hypothesis

    PubMed Central

    Theodore, Rachel M.; Blumstein, Sheila E.; Luthra, Sahil

    2015-01-01

    Findings in the domain of spoken word recognition indicate that lexical representations contain both abstract and episodic information. It has been proposed that processing time determines when each source of information is recruited, with increased processing time required to access lower-frequency episodic instantiations. The time-course hypothesis of specificity effects thus identifies a strong role for retrieval mechanisms mediating the use of abstract versus episodic information. Here we conducted three recognition memory experiments to examine whether findings previously attributed to retrieval mechanisms might reflect attention during encoding. Results from Experiment 1 showed that talker-specificity effects emerged when subjects attended to individual speakers during encoding, but not when they attended to lexical characteristics during encoding, even though processing time at retrieval was equivalent. Results from Experiment 2 showed that talker-specificity effects emerged when listeners attended to talker gender but not when they attended to syntactic characteristics, even though processing time at retrieval was significantly longer in the latter condition. Results from Experiment 3 showed no talker-specificity effects when attending to lexical characteristics even when processing at retrieval was slowed by the addition of background noise. Collectively, these results suggest that when processing time during retrieval is decoupled from encoding factors, it fails to predict the emergence of talker-specificity effects. Rather, attention during encoding appears to be the putative variable. PMID:25824889

  5. Wake-up-word speech recognition application for first responder communication enhancement

    NASA Astrophysics Data System (ADS)

    Këpuska, Veton; Breitfeller, Jason

    2006-05-01

    Speech Recognition systems, historically, have proven to be cumbersome and insufficiently accurate for a range of applications. The ultimate goal of our proposed technology is to fundamentally change the way current Speech Recognition (SR) systems interact with humans and develop an application that is extremely hardware efficient. Accurate SR and reasonable hardware requirements will afford the average first responder officer, e.g., police officer, a true break-through technology that will change the way an officer performs his duties. The presented technology provides a cutting-edge solution for human-machine interaction through the utilization of a properly solved Wake-Up-Word (WUW) SR problem. This paradigm-shift provides the basis for development of SR systems with truly "Voice Activated" capabilities, impacting all SR based technologies and the way in which humans interact with computers. This shift is a radical departure from the current "push-to-talk" paradigm currently applied to all speech-to-text or speech-recognition applications. To be able to achieve this goal, a significantly more accurate pattern classification and scoring technique is required, which in turn provides SR systems enhanced performance for correct recognition (i.e., minimization of false rejection) as well as correct rejection (i.e., minimization of false acceptance). A revolutionary and innovative classification and scoring technique is used that is a significant enhancement over an earlier method presented in reference [1]. The solution in reference [1] has been demonstrated to meet the stringent requirements of the WUW-SR task. Advanced solution of [1] is a novel technique that is model and algorithm independent. Therefore, it could be used to significantly improve performance of existing recognition algorithms and systems. Reduction of error rates of over 40% are commonly observed for both false rejections and false acceptance. In this paper the architecture of the WUW-SR based

  6. Joint Effect of Insertion of Spaces and Word Length in Saccade Target Selection in Chinese Reading

    ERIC Educational Resources Information Center

    Li, Xingshan; Shen, Wei

    2013-01-01

    The present study examined how insertion of spaces before and after a word affects saccade target selection in Chinese reading. We found that inserting spaces in Chinese text changes the eye movement behaviour of Chinese readers. They are less likely to fixate on the character near the space and will try their best to process the entire word with…

  7. Re-evaluating split-fovea processing in word recognition: effects of retinal eccentricity on hemispheric dominance.

    PubMed

    Jordan, Timothy R; Paterson, Kevin B; Stachurski, Marcin

    2008-11-01

    Several studies have claimed that hemispheric asymmetries affect word recognition right up to the point of fixation because each fovea is split precisely at its vertical midline and information presented either side of this midline projects unilaterally to different, contralateral hemispheres. To investigate this claim, four-letter words were presented to the left or right of fixation, either close to fixation entirely in foveal vision (0.15, 0.25, and 0.35 degrees from fixation) or further from fixation entirely in extrafoveal vision (2.00, 2.10, and 2.20 degrees from fixation). Fixation location and stimulus presentation were controlled using an eye-tracker linked to a fixation-contingent display and performance was assessed using a forced-choice task to suppress confounding effects of guesswork. A left hemisphere advantage was observed for words presented in extrafoveal locations but no hemisphere advantage (left or right) was observed for words presented in any foveal location. These findings support the well-established view that words encountered outside foveal vision project to different, contralateral hemispheres but indicate that this division for word recognition occurs only outside the fovea and provide no support for the claim that a functional split in hemispheric processing exists at the point of fixation. PMID:18999347

  8. Recognition of spoken words by native and non-native listeners: Talker-, listener-, and item-related factors

    PubMed Central

    Bradlow, Ann R.; Pisoni, David B.

    2012-01-01

    In order to gain insight into the interplay between the talker-, listener-, and item-related factors that influence speech perception, a large multi-talker database of digitally recorded spoken words was developed, and was then submitted to intelligibility tests with multiple listeners. Ten talkers produced two lists of words at three speaking rates. One list contained lexically “easy” words (words with few phonetically similar sounding “neighbors” with which they could be confused), and the other list contained lexically “hard” (wordswords with many phonetically similar sounding “neighbors”). An analysis of the intelligibility data obtained with native speakers of English (experiment 1) showed a strong effect of lexical similarity. Easy words had higher intelligibility scores than hard words. A strong effect of speaking rate was also found whereby slow and medium rate words had higher intelligibility scores than fast rate words. Finally, a relationship was also observed between the various stimulus factors whereby the perceptual difficulties imposed by one factor, such as a hard word spoken at a fast rate, could be overcome by the advantage gained through the listener's experience and familiarity with the speech of a particular talker. In experiment 2, the investigation was extended to another listener population, namely, non-native listeners. Results showed that the ability to take advantage of surface phonetic information, such as a consistent talker across items, is a perceptual skill that transfers easily from first to second language perception. However, non-native listeners had particular difficulty with lexically hard words even when familiarity with the items was controlled, suggesting that non-native word recognition may be compromised when fine phonetic discrimination at the segmental level is required. Taken together, the results of this study provide insight into the signal-dependent and signal-independent factors that influence spoken

  9. Many neighbors are not silent. fMRI evidence for global lexical activity in visual word recognition.

    PubMed

    Braun, Mario; Jacobs, Arthur M; Richlan, Fabio; Hawelka, Stefan; Hutzler, Florian; Kronbichler, Martin

    2015-01-01

    Many neurocognitive studies investigated the neural correlates of visual word recognition, some of which manipulated the orthographic neighborhood density of words and nonwords believed to influence the activation of orthographically similar representations in a hypothetical mental lexicon. Previous neuroimaging research failed to find evidence for such global lexical activity associated with neighborhood density. Rather, effects were interpreted to reflect semantic or domain general processing. The present fMRI study revealed effects of lexicality, orthographic neighborhood density and a lexicality by orthographic neighborhood density interaction in a silent reading task. For the first time we found greater activity for words and nonwords with a high number of neighbors. We propose that this activity in the dorsomedial prefrontal cortex reflects activation of orthographically similar codes in verbal working memory thus providing evidence for global lexical activity as the basis of the neighborhood density effect. The interaction of lexicality by neighborhood density in the ventromedial prefrontal cortex showed lower activity in response to words with a high number compared to nonwords with a high number of neighbors. In the light of these results the facilitatory effect for words and inhibitory effect for nonwords with many neighbors observed in previous studies can be understood as being due to the operation of a fast-guess mechanism for words and a temporal deadline mechanism for nonwords as predicted by models of visual word recognition. Furthermore, we propose that the lexicality effect with higher activity for words compared to nonwords in inferior parietal and middle temporal cortex reflects the operation of an identification mechanism based on local lexico-semantic activity. PMID:26257634

  10. Many neighbors are not silent. fMRI evidence for global lexical activity in visual word recognition.

    PubMed

    Braun, Mario; Jacobs, Arthur M; Richlan, Fabio; Hawelka, Stefan; Hutzler, Florian; Kronbichler, Martin

    2015-01-01

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

  11. ERP profiles for face and word recognition are based on their status in semantic memory not their stimulus category.

    PubMed

    Nie, Aiqing; Griffin, Michael; Keinath, Alexander; Walsh, Matthew; Dittmann, Andrea; Reder, Lynne

    2014-04-01

    Previous research has suggested that faces and words are processed and remembered differently as reflected by different ERP patterns for the two types of stimuli. Specifically, face stimuli produced greater late positive deflections for old items in anterior compared to posterior regions, while word stimuli produced greater late positive deflections in posterior compared to anterior regions. Given that words have existing representations in subjects׳ long-term memories (LTM) and that face stimuli used in prior experiments were of unknown individuals, we conducted an ERP study that crossed face and letter stimuli with the presence or absence of a prior (stable or existing) memory representation. During encoding, subjects judged whether stimuli were known (famous face or real word) or not known (unknown person or pseudo-word). A surprise recognition memory test required subjects to distinguish between stimuli that appeared during the encoding phase and stimuli that did not. ERP results were consistent with previous research when comparing unknown faces and words; however, the late ERP pattern for famous faces was more similar to that for words than for unknown faces. This suggests that the critical ERP difference is mediated by whether there is a prior representation in LTM, and not whether the stimulus involves letters or faces.

  12. I see/hear what you mean: semantic activation in visual word recognition depends on perceptual attention.

    PubMed

    Connell, Louise; Lynott, Dermot

    2014-04-01

    How does the meaning of a word affect how quickly we can recognize it? Accounts of visual word recognition allow semantic information to facilitate performance but have neglected the role of modality-specific perceptual attention in activating meaning. We predicted that modality-specific semantic information would differentially facilitate lexical decision and reading aloud, depending on how perceptual attention is implicitly directed by each task. Large-scale regression analyses showed the perceptual modalities involved in representing a word's referent concept influence how easily that word is recognized. Both lexical decision and reading-aloud tasks direct attention toward vision, and are faster and more accurate for strongly visual words. Reading aloud additionally directs attention toward audition and is faster and more accurate for strongly auditory words. Furthermore, the overall semantic effects are as large for reading aloud as lexical decision and are separable from age-of-acquisition effects. These findings suggest that implicitly directing perceptual attention toward a particular modality facilitates representing modality-specific perceptual information in the meaning of a word, which in turn contributes to the lexical decision or reading-aloud response.

  13. Sequential processing in hemispheric word recognition: the impact of initial letter discriminability on the OUP naming effect.

    PubMed

    Lindell, Annukka K; Nicholls, Michael E R; Kwantes, Peter J; Castles, Anne

    2005-05-01

    The cerebral hemispheres have been proposed to engage different word recognition strategies: the left hemisphere implementing a parallel, and the right hemisphere, a sequential, analysis. To investigate this notion, we asked participants to name words with an early or late orthographic uniqueness point (OUP), presented horizontally to their left (LVF), right (RVF), or both fields of vision (BVF). Consistent with past foveal research, Experiment 1 produced a robust facilitatory effect of early OUP for RVF/BVF presentations, indicating the presence of sequential processes in lexical retrieval. The effect was absent for LVF trials, which we argue results from the disadvantaged position of initial letters of words presented in the LVF. To test this proposition, Experiment 2 assessed the discriminability of various letter positions in the visual fields using a bar-probe task. The obtained error functions highlighted the poor discriminability of initial letters in the LVF and latter letters in the RVF. To confirm that this asymmetry in initial letter acuity was responsible for the absent OUP effect for LVF presentations, Experiment 3 replicated Experiment 1 using vertical stimulus presentations. Results indicated a marked facilitatory effect of early OUP across visual fields, supporting our contention that the lack of OUP effect for LVF presentations in Experiment 1 resulted from poor discriminability of the initial letters. These findings confirm the presence of sequential processes in both left and right hemisphere word recognition, casting doubt on parallel models of word processing.

  14. Design and performance of a large vocabulary discrete word recognition system. Volume 1: Technical report. [real time computer technique for voice data processing

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The development, construction, and test of a 100-word vocabulary near real time word recognition system are reported. Included are reasonable replacement of any one or all 100 words in the vocabulary, rapid learning of a new speaker, storage and retrieval of training sets, verbal or manual single word deletion, continuous adaptation with verbal or manual error correction, on-line verification of vocabulary as spoken, system modes selectable via verification display keyboard, relationship of classified word to neighboring word, and a versatile input/output interface to accommodate a variety of applications.

  15. Target recognition for ladar range image using slice image

    NASA Astrophysics Data System (ADS)

    Xia, Wenze; Han, Shaokun; Wang, Liang

    2015-12-01

    A shape descriptor and a complete shape-based recognition system using slice images as geometric feature descriptor for ladar range images are introduced. A slice image is a two-dimensional image generated by three-dimensional Hough transform and the corresponding mathematical transformation. The system consists of two processes, the model library construction and recognition. In the model library construction process, a series of range images are obtained after the model object is sampled at preset attitude angles. Then, all the range images are converted into slice images. The number of slice images is reduced by clustering analysis and finding a representation to reduce the size of the model library. In the recognition process, the slice image of the scene is compared with the slice image in the model library. The recognition results depend on the comparison. Simulated ladar range images are used to analyze the recognition and misjudgment rates, and comparison between the slice image representation method and moment invariants representation method is performed. The experimental results show that whether in conditions without noise or with ladar noise, the system has a high recognition rate and low misjudgment rate. The comparison experiment demonstrates that the slice image has better representation ability than moment invariants.

  16. Stimulus Onset Asynchrony and the Timeline of Word Recognition: Event-Related Potentials during Sentence Reading

    ERIC Educational Resources Information Center

    Dambacher, Michael; Dimigen, Olaf; Braun, Mario; Wille, Kristin; Jacobs, Arthur M.; Kliegl, Reinhold

    2012-01-01

    Three ERP experiments examined the effect of word presentation rate (i.e., stimulus onset asynchrony, SOA) on the time course of word frequency and predictability effects in sentence reading. In Experiments 1 and 2, sentences were presented word-by-word in the screen center at an SOA of 700 and 490ms, respectively. While these rates are typical…

  17. Impaired Word Recognition in Alzheimer's Disease: The Role of Age of Acquisition

    ERIC Educational Resources Information Center

    Cuetos, Fernando; Herrera, Elena; Ellis, Andrew W.

    2010-01-01

    Studies of word production in patients with Alzheimer's disease have identified the age of acquisition of words as an important predictor of retention or loss, with early acquired words remaining accessible for longer than later acquired words. If, as proposed by current theories, effects of age of acquisition reflect the involvement of semantic…

  18. Tune in to the Tone: Lexical Tone Identification is Associated with Vocabulary and Word Recognition Abilities in Young Chinese Children.

    PubMed

    Tong, Xiuli; Tong, Xiuhong; McBride-Chang, Catherine

    2015-12-01

    Lexical tone is one of the most prominent features in the phonological representation of words in Chinese. However, little, if any, research to date has directly evaluated how young Chinese children's lexical tone identification skills contribute to vocabulary acquisition and character recognition. The present study distinguished lexical tones from segmental phonological awareness and morphological awareness in order to estimate the unique contribution of lexical tone in early vocabulary acquisition and character recognition. A sample of 199 Cantonese children aged 5-6 years was assessed on measures of lexical tone identification, segmental phonological awareness, morphological awareness, nonverbal ability, vocabulary knowledge, and Chinese character recognition. It was found that lexical tone awareness and morphological awareness were both associated with vocabulary knowledge and character recognition. However, there was a significant relationship between lexical tone awareness and both vocabulary knowledge and character recognition, even after controlling for the effects of age, nonverbal ability, segmental phonological awareness and morphological awareness. These findings suggest that lexical tone is a key factor accounting for individual variance in young children's lexical acquisition in Chinese, and that lexical tone should be considered in understanding how children learn new Chinese vocabulary words, in either oral or written forms. PMID:27483739

  19. Tune in to the Tone: Lexical Tone Identification is Associated with Vocabulary and Word Recognition Abilities in Young Chinese Children.

    PubMed

    Tong, Xiuli; Tong, Xiuhong; McBride-Chang, Catherine

    2015-12-01

    Lexical tone is one of the most prominent features in the phonological representation of words in Chinese. However, little, if any, research to date has directly evaluated how young Chinese children's lexical tone identification skills contribute to vocabulary acquisition and character recognition. The present study distinguished lexical tones from segmental phonological awareness and morphological awareness in order to estimate the unique contribution of lexical tone in early vocabulary acquisition and character recognition. A sample of 199 Cantonese children aged 5-6 years was assessed on measures of lexical tone identification, segmental phonological awareness, morphological awareness, nonverbal ability, vocabulary knowledge, and Chinese character recognition. It was found that lexical tone awareness and morphological awareness were both associated with vocabulary knowledge and character recognition. However, there was a significant relationship between lexical tone awareness and both vocabulary knowledge and character recognition, even after controlling for the effects of age, nonverbal ability, segmental phonological awareness and morphological awareness. These findings suggest that lexical tone is a key factor accounting for individual variance in young children's lexical acquisition in Chinese, and that lexical tone should be considered in understanding how children learn new Chinese vocabulary words, in either oral or written forms.

  20. Emotion effects during reading: Influence of an emotion target word on eye movements and processing.

    PubMed

    Knickerbocker, Hugh; Johnson, Rebecca L; Altarriba, Jeanette

    2015-01-01

    Recently, Scott, O'Donnell and Sereno reported that words of high valence and arousal are processed with greater ease than neutral words during sentence reading. However, this study unsystematically intermixed emotion (label a state of mind, e.g., terrified or happy) and emotion-laden words (refer to a concept that is associated with an emotional state, e.g., debt or marriage). We compared the eye-movement record while participants read sentences that contained a neutral target word (e.g., chair) or an emotion word (no emotion-laden words were included). Readers were able to process both positive (e.g., happy) and negative emotion words (e.g., distressed) faster than neutral words. This was true across a wide range of early (e.g., first fixation durations) and late (e.g., total times on the post-target region) measures. Additional analyses revealed that State Trait Anxiety Inventory scores interacted with the emotion effect and that the emotion effect was not due to arousal alone.

  1. Logical metonymy resolution in a words-as-cues framework: evidence from self-paced reading and probe recognition.

    PubMed

    Zarcone, Alessandra; Padó, Sebastian; Lenci, Alessandro

    2014-06-01

    Logical metonymy resolution (begin a book → begin reading a book or begin writing a book) has traditionally been explained either through complex lexical entries (qualia structures) or through the integration of the implicit event via post-lexical access to world knowledge. We propose that recent work within the words-as-cues paradigm can provide a more dynamic model of logical metonymy, accounting for early and dynamic integration of complex event information depending on previous contextual cues (agent and patient). We first present a self-paced reading experiment on German subordinate sentences, where metonymic sentences and their paraphrased version differ only in the presence or absence of the clause-final target verb (Der Konditor begann die Glasur → Der Konditor begann, die Glasur aufzutragen/The baker began the icing → The baker began spreading the icing). Longer reading times at the target verb position in a high-typicality condition (baker + icing → spread ) compared to a low-typicality (but still plausible) condition (child + icing → spread) suggest that we make use of knowledge activated by lexical cues to build expectations about events. The early and dynamic integration of event knowledge in metonymy interpretation is bolstered by further evidence from a second experiment using the probe recognition paradigm. Presenting covert events as probes following a high-typicality or a low-typicality metonymic sentence (Der Konditor begann die Glasur → AUFTRAGEN/The baker began the icing → SPREAD), we obtain an analogous effect of typicality at 100 ms interstimulus interval.

  2. Does Kaniso activate CASINO?: input coding schemes and phonology in visual-word recognition.

    PubMed

    Acha, Joana; Perea, Manuel

    2010-01-01

    Most recent input coding schemes in visual-word recognition assume that letter position coding is orthographic rather than phonological in nature (e.g., SOLAR, open-bigram, SERIOL, and overlap). This assumption has been drawn - in part - by the fact that the transposed-letter effect (e.g., caniso activates CASINO) seems to be (mostly) insensitive to phonological manipulations (e.g., Perea & Carreiras, 2006, 2008; Perea & Pérez, 2009). However, one could argue that the lack of a phonological effect in prior research was due to the fact that the manipulation always occurred in internal letter positions - note that phonological effects tend to be stronger for the initial syllable (Carreiras, Ferrand, Grainger, & Perea, 2005). To reexamine this issue, we conducted a masked priming lexical decision experiment in which we compared the priming effect for transposed-letter pairs (e.g., caniso-CASINO vs. caviro-CASINO) and for pseudohomophone transposed-letter pairs (kaniso-CASINO vs. kaviro-CASINO). Results showed a transposed-letter priming effect for the correctly spelled pairs, but not for the pseudohomophone pairs. This is consistent with the view that letter position coding is (primarily) orthographic in nature.

  3. Spoken word recognition by Latino children learning Spanish as their first language*

    PubMed Central

    HURTADO, NEREYDA; MARCHMAN, VIRGINIA A.; FERNALD, ANNE

    2010-01-01

    Research on the development of efficiency in spoken language understanding has focused largely on middle-class children learning English. Here we extend this research to Spanish-learning children (n=49; M=2;0; range=1;3–3;1) living in the USA in Latino families from primarily low socioeconomic backgrounds. Children looked at pictures of familiar objects while listening to speech naming one of the objects. Analyses of eye movements revealed developmental increases in the efficiency of speech processing. Older children and children with larger vocabularies were more efficient at processing spoken language as it unfolds in real time, as previously documented with English learners. Children whose mothers had less education tended to be slower and less accurate than children of comparable age and vocabulary size whose mothers had more schooling, consistent with previous findings of slower rates of language learning in children from disadvantaged backgrounds. These results add to the cross-linguistic literature on the development of spoken word recognition and to the study of the impact of socioeconomic status (SES) factors on early language development. PMID:17542157

  4. Theories of Spoken Word Recognition Deficits in Aphasia: Evidence from Eye-Tracking and Computational Modeling

    PubMed Central

    Mirman, Daniel; Yee, Eiling; Blumstein, Sheila E.; Magnuson, James S.

    2011-01-01

    We used eye tracking to investigate lexical processing in aphasic participants by examining the fixation time course for rhyme (e.g., carrot – parrot) and cohort (e.g., beaker – beetle) competitors. Broca’s aphasic participants exhibited larger rhyme competition effects than age-matched controls. A reanalysis of previously reported data (Yee, Blumstein, & Sedivy, 2008) confirmed that Wernicke’s aphasic participants exhibited larger cohort competition effects. Individual-level analyses revealed a negative correlation between rhyme and cohort competition effect size across both groups of aphasic participants. Computational model simulations were performed to examine which of several accounts of lexical processing deficits in aphasia might account for the observed effects. Simulation results revealed that slower deactivation of lexical competitors could account for increased cohort competition in Wernicke’s aphasic participants; auditory perceptual impairment could account for increased rhyme competition in Broca's aphasic participants; and a perturbation of a parameter controlling selection among competing alternatives could account for both patterns, as well as the correlation between the effects. In light of these simulation results, we discuss theoretical accounts that have the potential to explain the dynamics of spoken word recognition in aphasia and the possible roles of anterior and posterior brain regions in lexical processing and cognitive control. PMID:21371743

  5. Visual and Acoustic Confusability of Target Letters and the Word Superiority Effect.

    ERIC Educational Resources Information Center

    Chastain, Garvin; And Others

    The hypothesis that word context reduces visual rather than acoustic confusion between possible targets was tested in a series of experiments. All involved tachistoscopic presentation of letter strings followed by a pattern mask. Data from eight college students showed that target letters that are confusable only visually and acoustically ("b" and…

  6. A universal entropy-driven mechanism for thioredoxin-target recognition.

    PubMed

    Palde, Prakash B; Carroll, Kate S

    2015-06-30

    Cysteine residues in cytosolic proteins are maintained in their reduced state, but can undergo oxidation owing to posttranslational modification during redox signaling or under conditions of oxidative stress. In large part, the reduction of oxidized protein cysteines is mediated by a small 12-kDa thiol oxidoreductase, thioredoxin (Trx). Trx provides reducing equivalents for central metabolic enzymes and is implicated in redox regulation of a wide number of target proteins, including transcription factors. Despite its importance in cellular redox homeostasis, the precise mechanism by which Trx recognizes target proteins, especially in the absence of any apparent signature binding sequence or motif, remains unknown. Knowledge of the forces associated with the molecular recognition that governs Trx-protein interactions is fundamental to our understanding of target specificity. To gain insight into Trx-target recognition, we have thermodynamically characterized the noncovalent interactions between Trx and target proteins before S-S reduction using isothermal titration calorimetry (ITC). Our findings indicate that Trx recognizes the oxidized form of its target proteins with exquisite selectivity, compared with their reduced counterparts. Furthermore, we show that recognition is dependent on the conformational restriction inherent to oxidized targets. Significantly, the thermodynamic signatures for multiple Trx targets reveal favorable entropic contributions as the major recognition force dictating these protein-protein interactions. Taken together, our data afford significant new insight into the molecular forces responsible for Trx-target recognition and should aid the design of new strategies for thiol oxidoreductase inhibition. PMID:26080424

  7. Dual Function of NRP1 in Axon Guidance and Subcellular Target Recognition in Cerebellum.

    PubMed

    Telley, Ludovic; Cadilhac, Christelle; Cioni, Jean-Michel; Saywell, Veronique; Jahannault-Talignani, Céline; Huettl, Rosa E; Sarrailh-Faivre, Catherine; Dayer, Alexandre; Huber, Andrea B; Ango, Fabrice

    2016-09-21

    Subcellular target recognition in the CNS is the culmination of a multiple-step program including axon guidance, target recognition, and synaptogenesis. In cerebellum, basket cells (BCs) innervate the soma and axon initial segment (AIS) of Purkinje cells (PCs) to form the pinceau synapse, but the underlying mechanisms remain incompletely understood. Here, we demonstrate that neuropilin-1 (NRP1), a Semaphorin receptor expressed in BCs, controls both axonal guidance and subcellular target recognition. We show that loss of Semaphorin 3A function or specific deletion of NRP1 in BCs alters the stereotyped organization of BC axon and impairs pinceau synapse formation. Further, we identified NRP1 as a trans-synaptic binding partner of the cell adhesion molecule neurofascin-186 (NF186) expressed in the PC AIS during pinceau synapse formation. These findings identify a dual function of NRP1 in both axon guidance and subcellular target recognition in the construction of GABAergic circuitry. PMID:27618676

  8. Get rich quick: the signal to respond procedure reveals the time course of semantic richness effects during visual word recognition.

    PubMed

    Hargreaves, Ian S; Pexman, Penny M

    2014-05-01

    According to several current frameworks, semantic processing involves an early influence of language-based information followed by later influences of object-based information (e.g., situated simulations; Santos, Chaigneau, Simmons, & Barsalou, 2011). In the present study we examined whether these predictions extend to the influence of semantic variables in visual word recognition. We investigated the time course of semantic richness effects in visual word recognition using a signal-to-respond (STR) paradigm fitted to a lexical decision (LDT) and a semantic categorization (SCT) task. We used linear mixed effects to examine the relative contributions of language-based (number of senses, ARC) and object-based (imageability, number of features, body-object interaction ratings) descriptions of semantic richness at four STR durations (75, 100, 200, and 400ms). Results showed an early influence of number of senses and ARC in the SCT. In both LDT and SCT, object-based effects were the last to influence participants' decision latencies. We interpret our results within a framework in which semantic processes are available to influence word recognition as a function of their availability over time, and of their relevance to task-specific demands.

  9. Improving word recognition in noise among hearing-impaired subjects with a single-channel cochlear noise-reduction algorithm.

    PubMed

    Fink, Nir; Furst, Miriam; Muchnik, Chava

    2012-09-01

    A common complaint of the hearing impaired is the inability to understand speech in noisy environments even with their hearing assistive devices. Only a few single-channel algorithms have significantly improved speech intelligibility in noise for hearing-impaired listeners. The current study introduces a cochlear noise reduction algorithm. It is based on a cochlear representation of acoustic signals and real-time derivation of a binary speech mask. The contribution of the algorithm for enhancing word recognition in noise was evaluated on a group of 42 normal-hearing subjects, 35 hearing-aid users, 8 cochlear implant recipients, and 14 participants with bimodal devices. Recognition scores of Hebrew monosyllabic words embedded in Gaussian noise at several signal-to-noise ratios (SNRs) were obtained with processed and unprocessed signals. The algorithm was not effective among the normal-hearing participants. However, it yielded a significant improvement in some of the hearing-impaired subjects under different listening conditions. Its most impressive benefit appeared among cochlear implant recipients. More than 20% improvement in recognition score of noisy words was obtained by 12, 16, and 26 hearing-impaired at SNR of 30, 24, and 18 dB, respectively. The algorithm has a potential to improve speech intelligibility in background noise, yet further research is required to improve its performances.

  10. Code-switching effects in bilingual word recognition: a masked priming study with event-related potentials.

    PubMed

    Chauncey, Krysta; Grainger, Jonathan; Holcomb, Phillip J

    2008-06-01

    Two experiments tested language switching effects with bilingual participants in a priming paradigm with masked primes (duration of 50ms in Experiment 1 and 100ms in Experiment 2). Participants had to monitor target words for animal names, and ERPs were recorded to critical (non-animal) words in L1 and L2 primed by unrelated words from the same or the other language. Both experiments revealed language priming (switching) effects that depended on target language. For target words in L1, most of the language switch effect appeared in the N400 ERP component, with L2 primes generating a more negative going wave than L1 primes. For L2 target words, on the other hand, the effects of a language switch appeared mainly in an earlier ERP component (N250) peaking at approximately 250ms post-target onset, and showing greater negativity following an L1 prime than an L2 prime. This is the first evidence for fast-acting language-switching effects occurring in the absence of overt task switching.

  11. Shape-and-motion-fused multiple flying target recognition and tracking

    NASA Astrophysics Data System (ADS)

    Kovács, Levente; Utasi, Ákos

    2010-04-01

    This paper presents an automatic approach for camera/image based detection, recognition and tracking of flying objects (planes, missiles, etc.). The method detects appearing objects, and recognizes re-appearing targets. It uses a feature-based statistical modeling approach (e.g. HMM) for motion-based recognition, and an image feature (e.g. shape) based indexed database of pre-trained object classes, suitable for recognition on known and alerting on unknown objects. The method can be used for detection of flying objects, recognition of the same object category through multiple views/cameras and signal on unusual motions and shape appearances.

  12. The effect of word length on hemispheric word recognition: evidence from unilateral and bilateral-redundant presentations.

    PubMed

    Lindell, Annukka K; Nicholls, Michael E R; Castles, Anne E

    2002-01-01

    Visual half field studies have repeatedly demonstrated the left hemisphere's superiority for language processing. Previous studies examined the effect of word length on bilateral and unilateral performance by comparing foveal and parafoveal presentations. The present study removed the potential confound of acuity by using parafoveal presentations for both unilateral and bilateral trials. Twenty participants named 3-, 4-, 5-, and 6-letter words. The results supported previous findings, with right hemisphere performance being particularly degraded with increases in word length. There was no difference between left hemisphere and bihemispheric performance in terms of speed or accuracy, suggesting that bihemispheric performance is reliant upon the strategy of the hemisphere superior for language processing. Overall, the pattern of results supports the notion that the left hemisphere's superior linguistic capacity results from a more parallel processing strategy, while the right hemisphere is reliant upon a more sequential mechanism. PMID:12030486

  13. Recognition memory of neutral words can be impaired by task-irrelevant emotional encoding contexts: behavioral and electrophysiological evidence.

    PubMed

    Zhang, Qin; Liu, Xuan; An, Wei; Yang, Yang; Wang, Yinan

    2015-01-01

    Previous studies on the effects of emotional context on memory for centrally presented neutral items have obtained inconsistent results. And in most of those studies subjects were asked to either make a connection between the item and the context at study or retrieve both the item and the context. When no response for the contexts is required, how emotional contexts influence memory for neutral items is still unclear. Thus, the present study attempted to investigate the influences of four types of emotional picture contexts on recognition memory of neutral words using both behavioral and event-related potential (ERP) measurements. During study, words were superimposed centrally onto emotional contexts, and subjects were asked to just remember the words. During test, both studied and new words were presented without the emotional contexts and subjects had to make "old/new" judgments for those words. The results revealed that, compared with the neutral context, the negative contexts and positive high-arousing context impaired recognition of words. ERP results at encoding demonstrated that, compared with items presented in the neutral context, items in the positive and negative high-arousing contexts elicited more positive ERPs, which probably reflects an automatic process of attention capturing of high-arousing context as well as a conscious and effortful process of overcoming the interference of high-arousing context. During retrieval, significant FN400 old/new effects occurred in conditions of the negative low-arousing, positive, and neutral contexts but not in the negative high-arousing condition. Significant LPC old/new effects occurred in all conditions of context. However, the LPC old/new effect in the negative high-arousing condition was smaller than that in the positive high-arousing and low-arousing conditions. These results suggest that emotional context might influence both the familiarity and recollection processes.

  14. The modulation of visual and task characteristics of a writing system on hemispheric lateralization in visual word recognition-a computational exploration.

    PubMed

    Hsiao, Janet H; Lam, Sze Man

    2013-07-01

    Through computational modeling, here we examine whether visual and task characteristics of writing systems alone can account for lateralization differences in visual word recognition between different languages without assuming influence from left hemisphere (LH) lateralized language processes. We apply a hemispheric processing model of face recognition to visual word recognition; the model implements a theory of hemispheric asymmetry in perception that posits low spatial frequency biases in the right hemisphere and high spatial frequency (HSF) biases in the LH. We show two factors that can influence lateralization: (a) Visual similarity among words: The more similar the words in the lexicon look visually, the more HSF/LH processing is required to distinguish them, and (b) Requirement to decompose words into graphemes for grapheme-phoneme mapping: Alphabetic reading (involving grapheme-phoneme conversion) requires more HSF/LH processing than logographic reading (no grapheme-phoneme mapping). These factors may explain the difference in lateralization between English and Chinese orthographic processing.

  15. Infants Exposed to Fluent Natural Speech Succeed at Cross-Gender Word Recognition

    ERIC Educational Resources Information Center

    van Heugten, Marieke; Johnson, Elizabeth K.

    2012-01-01

    Purpose: To examine the possibility that early signal-to-word form mapping capabilities are robust enough to handle substantial indexical variation in the realization of words. Method: Two groups of 7.5-month-olds were tested with the Headturn Preference Procedure. Half of the infants were exposed to words embedded in passages spoken by their…

  16. It's What's on the Outside that Matters: An Advantage for External Features in Children's Word Recognition

    ERIC Educational Resources Information Center

    Webb, Tessa M.; Beech, John R.; Mayall, Kate M.; Andrews, Antony S.

    2006-01-01

    The relative importance of internal and external letter features of words in children's developing reading was investigated to clarify further the nature of early featural analysis. In Experiment 1, 72 6-, 8-, and 10-year-olds read aloud words displayed as wholes, external features only (central features missing, thereby preserving word shape…

  17. Word Recognition and Vocabulary Understanding Strategies for Literacy Success. Bill Harp Professional Teachers Library.

    ERIC Educational Resources Information Center

    Sinatra, Richard

    This book lets readers see how children and youth learn words in the oral and written languages--and how teachers can best assist learners in the understanding, reading, and writing of words for successful literacy development. In the book teachers learn the differing rationales for using sound/symbol or phonics approaches in word learning, for…

  18. What Do Letter Migration Errors Reveal About Letter Position Coding in Visual Word Recognition?

    ERIC Educational Resources Information Center

    Davis, Colin J.; Bowers, Jeffrey S.

    2004-01-01

    Dividing attention across multiple words occasionally results in misidentifications whereby letters apparently migrate between words. Previous studies have found that letter migrations preserve within-word letter position, which has been interpreted as support for position-specific letter coding. To investigate this issue, the authors used word…

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

    ERIC Educational Resources Information Center

    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. Cross-Language Effects in Written Word Recognition: The Case of Bilingual Deaf Children

    ERIC Educational Resources Information Center

    Ormel, Ellen; Hermans, Daan; Knoors, Harry; Verhoeven, Ludo

    2012-01-01

    In recent years, multiple studies have shown that the languages of a bilingual interact during processing. We investigated sign activation as deaf children read words. In a word-picture verification task, we manipulated the underlying sign equivalents. We presented children with word-picture pairs for which the sign translation equivalents varied…

  1. Kernel sparse coding method for automatic target recognition in infrared imagery using covariance descriptor

    NASA Astrophysics Data System (ADS)

    Yang, Chunwei; Yao, Junping; Sun, Dawei; Wang, Shicheng; Liu, Huaping

    2016-05-01

    Automatic target recognition in infrared imagery is a challenging problem. In this paper, a kernel sparse coding method for infrared target recognition using covariance descriptor is proposed. First, covariance descriptor combining gray intensity and gradient information of the infrared target is extracted as a feature representation. Then, due to the reason that covariance descriptor lies in non-Euclidean manifold, kernel sparse coding theory is used to solve this problem. We verify the efficacy of the proposed algorithm in terms of the confusion matrices on the real images consisting of seven categories of infrared vehicle targets.

  2. How Many Words Can Your Students Read? Using a Sign Language Game To Increase Sight Word Recognition.

    ERIC Educational Resources Information Center

    Brennan, Kathleen B.; Miller, April D.

    2000-01-01

    This article discusses using sign language to help students with learning disabilities remember sight words. It describes the rationale for using sign language, gives directions for playing a game called Sign-o (similar to the game Bingo), provides extension activities, and includes a game board ready for duplication. (Contains references.)…

  3. The Processing of Consonants and Vowels during Letter Identity and Letter Position Assignment in Visual-Word Recognition: An ERP Study

    ERIC Educational Resources Information Center

    Vergara-Martinez, Marta; Perea, Manuel; Marin, Alejandro; Carreiras, Manuel

    2011-01-01

    Recent research suggests that there is a processing distinction between consonants and vowels in visual-word recognition. Here we conjointly examine the time course of consonants and vowels in processes of letter identity and letter position assignment. Event related potentials (ERPs) were recorded while participants read words and pseudowords in…

  4. Charting the Functional Relevance of Broca's Area for Visual Word Recognition and Picture Naming in Dutch Using fMRI-Guided TMS

    ERIC Educational Resources Information Center

    Wheat, Katherine L.; Cornelissen, Piers L.; Sack, Alexander T.; Schuhmann, Teresa; Goebel, Rainer; Blomert, Leo

    2013-01-01

    Magnetoencephalography (MEG) has shown pseudohomophone priming effects at Broca's area (specifically pars opercularis of left inferior frontal gyrus and precentral gyrus; LIFGpo/PCG) within [approximately]100 ms of viewing a word. This is consistent with Broca's area involvement in fast phonological access during visual word recognition. Here we…

  5. Fearful contextual expression impairs the encoding and recognition of target faces: an ERP study

    PubMed Central

    Lin, Huiyan; Schulz, Claudia; Straube, Thomas

    2015-01-01

    Previous event-related potential (ERP) studies have shown that the N170 to faces is modulated by the emotion of the face and its context. However, it is unclear how the encoding of emotional target faces as reflected in the N170 is modulated by the preceding contextual facial expression when temporal onset and identity of target faces are unpredictable. In addition, no study as yet has investigated whether contextual facial expression modulates later recognition of target faces. To address these issues, participants in the present study were asked to identify target faces (fearful or neutral) that were presented after a sequence of fearful or neutral contextual faces. The number of sequential contextual faces was random and contextual and target faces were of different identities so that temporal onset and identity of target faces were unpredictable. Electroencephalography (EEG) data was recorded during the encoding phase. Subsequently, participants had to perform an unexpected old/new recognition task in which target face identities were presented in either the encoded or the non-encoded expression. ERP data showed a reduced N170 to target faces in fearful as compared to neutral context regardless of target facial expression. In the later recognition phase, recognition rates were reduced for target faces in the encoded expression when they had been encountered in fearful as compared to neutral context. The present findings suggest that fearful compared to neutral contextual faces reduce the allocation of attentional resources towards target faces, which results in limited encoding and recognition of target faces. PMID:26388751

  6. Readers extract character frequency information from nonfixated-target word at long pretarget fixations during Chinese reading.

    PubMed

    Ma, Guojie; Li, Xingshan; Rayner, Keith

    2015-10-01

    We performed 2 eye movement studies to explore whether readers can extract character or word frequency information from nonfixated-target words in Chinese reading. In Experiments 1A and 1B, we manipulated the character frequency of the first character in a 2-character target word and the word frequency of a 2-character target word, respectively. We found that fixation durations on the pretarget words were shorter when the first character of a 2-character target word was presented with high frequency. Such effects were not observed for word frequency manipulations of a 2-character target word. In particular, further analysis revealed that such effects only occurred for long pretarget fixations. These results for character and word frequency manipulations were replicated in a within-subjects design in Experiment 2. These findings are generally consistent with the notion that characters are processed in parallel during Chinese reading. However, we did not find evidence that words are processed in parallel during Chinese reading. PMID:26168144

  7. Brain-potential analysis of visual word recognition in dyslexics and typically reading children.

    PubMed

    Fraga González, Gorka; Zarić, Gojko; Tijms, Jurgen; Bonte, Milene; Blomert, Leo; van der Molen, Maurits W

    2014-01-01

    The specialization of visual brain areas for fast processing of printed words plays an important role in the acquisition of reading skills. Dysregulation of these areas may be among the deficits underlying developmental dyslexia. The present study examines the specificity of word activation in dyslexic children in 3rd grade by comparing early components of brain potentials elicited by visually presented words vs. strings of meaningless letter-like symbols. Results showed a more pronounced N1 component for words compared to symbols for both groups. The dyslexic group revealed larger left-lateralized, word-specific N1 responses than the typically reading group. Furthermore, positive correlations between N1 amplitudes and reading fluency were found in the dyslexic group. Our results support the notion of N1 as a sensitive index of visual word processing involved in reading fluency.

  8. Properdin: New roles in pattern recognition and target clearance

    PubMed Central

    Kemper, Claudia; Hourcade, Dennis E.

    2008-01-01

    Properdin was first described over 50 years ago by Louis Pillemer and his collaborators as a vital component of an antibody-independent complement activation pathway. In the 1970’s properdin was shown to be a stabilizing component of the alternative pathway convertases, the central enzymes of the complement cascade. Recently we have reported that properdin can also bind to target cells and microbes, provide a platform for convertase assembly and function, and promote target phagocytosis. Evidence is emerging that suggests that properdin interacts with a network of target ligands, phagocyte receptors, and serum regulators. Here we review the new findings and their possible implications. PMID:18692243

  9. Structural basis of diverse membrane target recognitions by ankyrins.

    PubMed

    Wang, Chao; Wei, Zhiyi; Chen, Keyu; Ye, Fei; Yu, Cong; Bennett, Vann; Zhang, Mingjie

    2014-01-01

    Ankyrin adaptors together with their spectrin partners coordinate diverse ion channels and cell adhesion molecules within plasma membrane domains and thereby promote physiological activities including fast signaling in the heart and nervous system. Ankyrins specifically bind to numerous membrane targets through their 24 ankyrin repeats (ANK repeats), although the mechanism for the facile and independent evolution of these interactions has not been resolved. Here we report the structures of ANK repeats in complex with an inhibitory segment from the C-terminal regulatory domain and with a sodium channel Nav1.2 peptide, respectively, showing that the extended, extremely conserved inner groove spanning the entire ANK repeat solenoid contains multiple target binding sites capable of accommodating target proteins with very diverse sequences via combinatorial usage of these sites. These structures establish a framework for understanding the evolution of ankyrins' membrane targets, with implications for other proteins containing extended ANK repeat domains. PMID:25383926

  10. [Biotherapies, immunotherapies, targeted therapies, biopharmaceuticals… which word should be used?].

    PubMed

    Watier, Hervé

    2014-05-01

    The ability to accurately describe and name medical advances is a prerequisite to foster public debates with scientists and physicians, and favour faith over fear among patients and citizens. Therapeutic antibodies are a good example of a medical breakthrough which has met with considerable clinical success, and which terminology has changed over the years. If the appellation serotherapy was appropriate a century ago, it has become obsolete. Recent names such as biotherapy, immunotherapy, targeted therapy, biopharmaceuticals have been introduced and are now commonly used, each of those can apply to therapeutic antibodies. It is thus interesting to question the real meaning of these different appellations. Our goal in this manuscript is to analyse the genesis of these terms but also to suggest how to simplify the terminology: biotherapy or targeted therapy need to be eliminated, as well as immunotherapy when communicating with non scientific public. It is recommended to favour the term biopharmaceuticals (biomédicaments in French), which clearly indicates the origin of these molecules, intermediate between chemical drugs and living biologics, whose borders need to be accurately defined also.

  11. Advances in Doppler recognition for ground moving target indication

    NASA Astrophysics Data System (ADS)

    Kealey, Paul G.; Jahangir, Mohammed

    2006-05-01

    Ground Moving Target Indication (GMTI) radar provides a day/night, all-weather, wide-area surveillance capability to detect moving vehicles and personnel. Current GMTI radar sensors are limited to only detecting and tracking targets. The exploitation of GMTI data would be greatly enhanced by a capability to recognize accurately the detections as significant classes of target. Doppler classification exploits the differential internal motion of targets, e.g. due to the tracks, limbs and rotors. Recently, the QinetiQ Bayesian Doppler classifier has been extended to include a helicopter class in addition to wheeled, tracked and personnel classes. This paper presents the performance for these four classes using a traditional low-resolution GMTI surveillance waveform with an experimental radar system. We have determined the utility of an "unknown output decision" for enhancing the accuracy of the declared target classes. A confidence method has been derived, using a threshold of the difference in certainties, to assign uncertain classifications into an "unknown class". The trade-off between fraction of targets declared and accuracy of the classifier has been measured. To determine the operating envelope of a Doppler classification algorithm requires a detailed understanding of the Signal-to-Noise Ratio (SNR) performance of the algorithm. In this study the SNR dependence of the QinetiQ classifier has been determined.

  12. Based on momentum method BP neural network in the target recognition research and application

    NASA Astrophysics Data System (ADS)

    Zhang, Xue-feng; Gao, Yu-bin

    2011-08-01

    Target recognition is measured by treating target existing knowledge to judge, analyze, and thus the process of target identification. Using anti-vibration lateral shearing interferometer to get the interference fringe for the spectrum information of measurement target, and the system can get the target by spectrum identification algorithm. By the condition that interferometer's length isn't changed, the system was optimized by momentum BP Neural Network algorithm in the separating mixed spectrum process, therefore it could improve the probability of camouflage target recognition. The spectrum information was calculated by the fringes, to getting the mixed spectrum data. The absorption spectrum was in the hidden layer, and the system obtained every kinds of characteristic spectrum from mixed spectrum by the momentum BP Neural Network. Experiments showed that it collected mixed spectrum of background form different distances and different surface, and made them to the initial spectrum information. The test target was a board that it's surface was made to four kinds, and there was no paint (A), brushing camouflage paint of military green (B), brushing camouflage paint of irregular shape (C) and brushing camouflage paint of irregular box (D). The mixed spectrum was obtained from the anti-vibration lateral shearing interferometer, while the recognition probability for non-camouflage target were above 90.0% by the traditional algorithm and the momentum BP neural network algorithm, but the recognition probability for camouflage target was 85.6% by momentum BP neural network algorithm, better than 41.5% by the traditional algorithm, so it proved that the algorithm could improve the recognition probability for camouflage target effectively.

  13. Target recognitions in multiple-camera closed-circuit television using color constancy

    NASA Astrophysics Data System (ADS)

    Soori, Umair; Yuen, Peter; Han, Ji Wen; Ibrahim, Izzati; Chen, Wentao; Hong, Kan; Merfort, Christian; James, David; Richardson, Mark

    2013-04-01

    People tracking in crowded scenes from closed-circuit television (CCTV) footage has been a popular and challenging task in computer vision. Due to the limited spatial resolution in the CCTV footage, the color of people's dress may offer an alternative feature for their recognition and tracking. However, there are many factors, such as variable illumination conditions, viewing angles, and camera calibration, that may induce illusive modification of intrinsic color signatures of the target. Our objective is to recognize and track targets in multiple camera views using color as the detection feature, and to understand if a color constancy (CC) approach may help to reduce these color illusions due to illumination and camera artifacts and thereby improve target recognition performance. We have tested a number of CC algorithms using various color descriptors to assess the efficiency of target recognition from a real multicamera Imagery Library for Intelligent Detection Systems (i-LIDS) data set. Various classifiers have been used for target detection, and the figure of merit to assess the efficiency of target recognition is achieved through the area under the receiver operating characteristics (AUROC). We have proposed two modifications of luminance-based CC algorithms: one with a color transfer mechanism and the other using a pixel-wise sigmoid function for an adaptive dynamic range compression, a method termed enhanced luminance reflectance CC (ELRCC). We found that both algorithms improve the efficiency of target recognitions substantially better than that of the raw data without CC treatment, and in some cases the ELRCC improves target tracking by over 100% within the AUROC assessment metric. The performance of the ELRCC has been assessed over 10 selected targets from three different camera views of the i-LIDS footage, and the averaged target recognition efficiency over all these targets is found to be improved by about 54% in AUROC after the data are processed by

  14. Building words on actions: verb enactment and verb recognition in children with specific language impairment.

    PubMed

    Levi, Gabriel; Colonnello, Valentina; Giacchè, Roberta; Piredda, Maria Letizia; Sogos, Carla

    2014-05-01

    Recent studies have shown that language processing is grounded in actions. Multiple independent research findings indicate that children with specific language impairment (SLI) show subtle difficulties beyond the language domain. Uncertainties remain on possible association between body-mediated, non-linguistic expression of verbs and early manifestation of SLI during verb acquisition. The present study was conducted to determine whether verb production through non-linguistic modalities is impaired in children with SLI. Children with SLI (mean age 41 months) and typically developing children (mean age 40 months) were asked to recognize target verbs while viewing video clips showing the action associated with the verb (verb-recognition task) and to enact the action corresponding to the verb (verb-enacting task). Children with SLI performed more poorly than control children in both tasks. The present study demonstrates that early language impairment emerges at the bodily level. These findings are consistent with the embodied theories of cognition and underscore the role of action-based representations during language development. PMID:24629540

  15. Pattern-Recognition System for Approaching a Known Target

    NASA Technical Reports Server (NTRS)

    Huntsberger, Terrance; Cheng, Yang

    2008-01-01

    A closed-loop pattern-recognition system is designed to provide guidance for maneuvering a small exploratory robotic vehicle (rover) on Mars to return to a landed spacecraft to deliver soil and rock samples that the spacecraft would subsequently bring back to Earth. The system could be adapted to terrestrial use in guiding mobile robots to approach known structures that humans could not approach safely, for such purposes as reconnaissance in military or law-enforcement applications, terrestrial scientific exploration, and removal of explosive or other hazardous items. The system has been demonstrated in experiments in which the Field Integrated Design and Operations (FIDO) rover (a prototype Mars rover equipped with a video camera for guidance) is made to return to a mockup of Mars-lander spacecraft. The FIDO rover camera autonomously acquires an image of the lander from a distance of 125 m in an outdoor environment. Then under guidance by an algorithm that performs fusion of multiple line and texture features in digitized images acquired by the camera, the rover traverses the intervening terrain, using features derived from images of the lander truss structure. Then by use of precise pattern matching for determining the position and orientation of the rover relative to the lander, the rover aligns itself with the bottom of ramps extending from the lander, in preparation for climbing the ramps to deliver samples to the lander. The most innovative aspect of the system is a set of pattern-recognition algorithms that govern a three-phase visual-guidance sequence for approaching the lander. During the first phase, a multifeature fusion algorithm integrates the outputs of a horizontal-line-detection algorithm and a wavelet-transform-based visual-area-of-interest algorithm for detecting the lander from a significant distance. The horizontal-line-detection algorithm is used to determine candidate lander locations based on detection of a horizontal deck that is part of the

  16. The Timing and Strength of Regional Brain Activation Associated with Word Recognition in Children with Reading Difficulties

    PubMed Central

    Rezaie, Roozbeh; Simos, Panagiotis G.; Fletcher, Jack M.; Juranek, Jenifer; Cirino, Paul T.; Li, Zhimin; Passaro, Antony D.; Papanicolaou, Andrew C.

    2011-01-01

    The study investigates the relative degree and timing of cortical activation across parietal, temporal, and frontal regions during performance of a continuous visual-word recognition task in children who experience reading difficulties (N = 44, RD) and typical readers (N = 40, NI). Minimum norm estimates of regional neurophysiological activity were obtained from magnetoencephalographic recordings. Children with RD showed bilaterally reduced neurophysiological activity in the superior and middle temporal gyri, and increased activity in rostral middle frontal and ventral occipitotemporal cortices, bilaterally. The temporal profile of activity in the RD group, featured near-simultaneous activity peaks in temporal, inferior parietal, and prefrontal regions, in contrast to a clear temporal progression of activity among these areas in the NI group. These results replicate and extend previous MEG and fMRI results demonstrating atypical, latency-dependent attributes of the brain circuit involved in word reading in children with reading difficulties. PMID:21647211

  17. Combined ERP/fMRI Evidence For Early Word Recognition Effects In The Posterior Inferior Temporal Gyrus

    PubMed Central

    Dien, Joseph; Brian, Eric S.; Molfese, Dennis L.; Gold, Brian T.

    2013-01-01

    Two brain regions with established roles in reading are the posterior middle temporal gyrus and the posterior fusiform gyrus. Lesion studies have also suggested that the region located between them, the posterior inferior temporal gyrus (pITG), plays a central role in word recognition. However, these lesion results could reflect disconnection effects since neuroimaging studies have not reported consistent lexicality effects in pITG. Here we tested whether these reported pITG lesion effects are due to disconnection effects or not using parallel ERP/fMRI studies. We predicted that the Recognition Potential (RP), a left-lateralized ERP negativity that peaks at about 200–250 ms, might be the electrophysiological correlate of pITG activity and that conditions that evoke the RP (perceptual degradation) might therefore also evoke pITG activity. In Experiment 1, twenty-three participants performed a lexical decision task (temporally flanked by supraliminal masks) while having high-density 129-channel ERP data collected. In Experiment 2, a separate group of fifteen participants underwent the same task while having fMRI data collected in a 3T scanner. Examination of the ERP data suggested that a canonical Recognition Potential effect was produced. The strongest corresponding effect in the fMRI data was in the vicinity of the pITG. In addition, results indicated stimulus-dependent functional connectivity between pITG and a region of the posterior fusiform gyrus near the visual word form area (VWFA) during word compared to nonword processing. These results provide convergent spatiotemporal evidence that the pITG contributes to early lexical access through interaction with the VWFA. PMID:23701693

  18. Deficits in audiovisual speech perception in normal aging emerge at the level of whole-word recognition.

    PubMed

    Stevenson, Ryan A; Nelms, Caitlin E; Baum, Sarah H; Zurkovsky, Lilia; Barense, Morgan D; Newhouse, Paul A; Wallace, Mark T

    2015-01-01

    Over the next 2 decades, a dramatic shift in the demographics of society will take place, with a rapid growth in the population of older adults. One of the most common complaints with healthy aging is a decreased ability to successfully perceive speech, particularly in noisy environments. In such noisy environments, the presence of visual speech cues (i.e., lip movements) provide striking benefits for speech perception and comprehension, but previous research suggests that older adults gain less from such audiovisual integration than their younger peers. To determine at what processing level these behavioral differences arise in healthy-aging populations, we administered a speech-in-noise task to younger and older adults. We compared the perceptual benefits of having speech information available in both the auditory and visual modalities and examined both phoneme and whole-word recognition across varying levels of signal-to-noise ratio. For whole-word recognition, older adults relative to younger adults showed greater multisensory gains at intermediate SNRs but reduced benefit at low SNRs. By contrast, at the phoneme level both younger and older adults showed approximately equivalent increases in multisensory gain as signal-to-noise ratio decreased. Collectively, the results provide important insights into both the similarities and differences in how older and younger adults integrate auditory and visual speech cues in noisy environments and help explain some of the conflicting findings in previous studies of multisensory speech perception in healthy aging. These novel findings suggest that audiovisual processing is intact at more elementary levels of speech perception in healthy-aging populations and that deficits begin to emerge only at the more complex word-recognition level of speech signals.

  19. Deficits in audiovisual speech perception in normal aging emerge at the level of whole-word recognition

    PubMed Central

    Stevenson, Ryan A.; Nelms, Caitlin; Baum, Sarah H.; Zurkovsky, Lilia; Barense, Morgan D.; Newhouse, Paul A.; Wallace, Mark T.

    2014-01-01

    Over the next two decades, a dramatic shift in the demographics of society will take place, with a rapid growth in the population of older adults. One of the most common complaints with healthy aging is a decreased ability to successfully perceive speech, particularly in noisy environments. In such noisy environments, the presence of visual speech cues (i.e., lip movements) provide striking benefits for speech perception and comprehension, but previous research suggests that older adults gain less from such audiovisual integration than their younger peers. To determine at what processing level these behavioral differences arise in healthy-aging populations, we administered a speech-in-noise task to younger and older adults. We compared the perceptual benefits of having speech information available in both the auditory and visual modalities and examined both phoneme and whole-word recognition across varying levels of signal-to-noise ratio (SNR). For whole-word recognition, older relative to younger adults showed greater multisensory gains at intermediate SNRs, but reduced benefit at low SNRs. By contrast, at the phoneme level both younger and older adults showed approximately equivalent increases in multisensory gain as SNR decreased. Collectively, the results provide important insights into both the similarities and differences in how older and younger adults integrate auditory and visual speech cues in noisy environments, and help explain some of the conflicting findings in previous studies of multisensory speech perception in healthy aging. These novel findings suggest that audiovisual processing is intact at more elementary levels of speech perception in healthy aging populations, and that deficits begin to emerge only at the more complex, word-recognition level of speech signals. PMID:25282337

  20. Acquired Affective Associations Induce Emotion Effects in Word Recognition: An ERP Study

    ERIC Educational Resources Information Center

    Fritsch, Nathalie; Kuchinke, Lars

    2013-01-01

    The present study examined how contextual learning and in particular emotionality conditioning impacts the neural processing of words, as possible key factors for the acquisition of words' emotional connotation. 21 participants learned on five consecutive days associations between meaningless pseudowords and unpleasant or neutral pictures using an…

  1. Word Recognition Processing Efficiency as a Component of Second Language Listening

    ERIC Educational Resources Information Center

    Joyce, Paul

    2013-01-01

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

  2. The Shape of Things to Come: Evaluating Word Frequency as a Continuous Variable in Recognition Memory

    ERIC Educational Resources Information Center

    Hemmer, Pernille; Criss, Amy H.

    2013-01-01

    The role of experience in memory, specifically the word frequency (WF) mirror effect showing higher hit rates and lower false alarm rates for low-frequency words, is one of the hallmarks of memory. However, this "regularity of memory" is limited because normative WF has been treated as discrete (low vs. high). We evaluate the extent to…

  3. The Role of Saccade Preparation in Lateralized Word Recognition: Evidence for the Attentional Bias Theory

    ERIC Educational Resources Information Center

    Perez, Dorine Vergilino; Lemoine, Christelle; Sieroff, Eric; Ergis, Anne-Marie; Bouhired, Redha; Rigault, Emilie; Dore-Mazars, Karine

    2012-01-01

    Words presented to the right visual field (RVF) are recognized more readily than those presented to the left visual field (LVF). Whereas the attentional bias theory proposes an explanation in terms of attentional imbalance between visual fields, the attentional advantage theory assumes that words presented to the RVF are processed automatically…

  4. The KEY to the ROCK: Near-Homophony in Nonnative Visual Word Recognition

    ERIC Educational Resources Information Center

    Ota, Mitsuhiko; Hartsuiker, Robert J.; Haywood, Sarah L.

    2009-01-01

    To test the hypothesis that native language (L1) phonology can affect the lexical representations of nonnative words, a visual semantic-relatedness decision task in English was given to native speakers and nonnative speakers whose L1 was Japanese or Arabic. In the critical conditions, the word pair contained a homophone or near-homophone of a…

  5. The Mechanisms Underlying the Interhemispheric Integration of Information in Foveal Word Recognition: Evidence for Transcortical Inhibition

    ERIC Educational Resources Information Center

    Van der Haegen, Lise; Brysbaert, Marc

    2011-01-01

    Words are processed as units. This is not as evident as it seems, given the division of the human cerebral cortex in two hemispheres and the partial decussation of the optic tract. In two experiments, we investigated what underlies the unity of foveally presented words: A bilateral projection of visual input in foveal vision, or interhemispheric…

  6. See before You Jump: Full Recognition of Parafoveal Words Precedes Skips during Reading

    ERIC Educational Resources Information Center

    Gordon, Peter C.; Plummer, Patrick; Choi, Wonil

    2013-01-01

    Serial attention models of eye-movement control during reading were evaluated in an eye-tracking experiment that examined how lexical activation combines with visual information in the parafovea to affect word skipping (where a word is not fixated during first-pass reading). Lexical activation was manipulated by repetition priming created through…

  7. Further Analysis of Picture Interference when Teaching Word Recognition to Children with Autism

    ERIC Educational Resources Information Center

    Dittlinger, Laura Harper; Lerman, Dorothea C.

    2011-01-01

    Previous research indicates that pairing pictures with associated words when teaching sight-word reading may hinder acquisition (e.g., Didden, Prinsen, & Sigafoos, 2000; Singh & Solman, 1990; Solman & Singh, 1992). The purpose of the current study was to determine whether this phenomenon was due to a previously learned association between the…

  8. Revisiting Age-of-Acquisition Effects in Spanish Visual Word Recognition: The Role of Item Imageability

    ERIC Educational Resources Information Center

    Wilson, Maximiliano A.; Cuetos, Fernando; Davies, Rob; Burani, Cristina

    2013-01-01

    Word age-of-acquisition (AoA) affects reading. The mapping hypothesis predicts AoA effects when input--output mappings are arbitrary. In Spanish, the orthography-to-phonology mappings required for word naming are consistent; therefore, no AoA effects are expected. Nevertheless, AoA effects have been found, motivating the present investigation of…

  9. Morphological Decomposition in the Recognition of Prefixed and Suffixed Words: Evidence from Korean

    ERIC Educational Resources Information Center

    Kim, Say Young; Wang, Min; Taft, Marcus

    2015-01-01

    Korean has visually salient syllable units that are often mapped onto either prefixes or suffixes in derived words. In addition, prefixed and suffixed words may be processed differently given a left-to-right parsing procedure and the need to resolve morphemic ambiguity in prefixes in Korean. To test this hypothesis, four experiments using the…

  10. Word Recognition and Syntactic Attachment in Reading: Evidence for a Staged Architecture

    ERIC Educational Resources Information Center

    Staub, Adrian

    2011-01-01

    In 3 experiments, the author examined how readers' eye movements are influenced by joint manipulations of a word's frequency and the syntactic fit of the word in its context. In the critical conditions of the first 2 experiments, a high- or low-frequency verb was used to disambiguate a garden-path sentence, while in the last experiment, a high- or…

  11. Target recognition in passive terahertz image of human body

    NASA Astrophysics Data System (ADS)

    Zhao, Ran; Zhao, Yuan-meng; Deng, Chao; Zhang, Cun-lin; Li, Yue

    2014-11-01

    THz radiation can penetrate through many nonpolar dielectric materials and can be used for nondestructive/noninvasive sensing and imaging of targets under nonpolar, nonmetallic covers or containers. Thus using THz systems to "see through" concealing barriers (i.e. packaging, corrugated cardboard, clothing) has been proposed as a new security screening method. Objects that can be detected by THz include concealed weapons, explosives, and chemical agents under clothing. Passive THz imaging system can detect THz wave from human body without transmit any electromagnetic wave, and the suspicious objects will become visible because the THz wave is blocked by this items. We can find out whether or not someone is carrying dangerous objects through this image. In this paper, the THz image enhancement, segmentation and contour extraction algorithms were studied to achieve effective target image detection. First, the terahertz images are enhanced and their grayscales are stretched. Then we apply global threshold segmentation to extract the target, and finally the targets are marked on the image. Experimental results showed that the algorithm proposed in this paper can extract and mark targets effectively, so that people can identify suspicious objects under clothing quickly. The algorithm can significantly improve the usefulness of the terahertz security apparatus.

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

    PubMed

    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.

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

    PubMed

    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. PMID:26277018

  14. Testing of a Composite Wavelet Filter to Enhance Automated Target Recognition in SONAR

    NASA Technical Reports Server (NTRS)

    Chiang, Jeffrey N.

    2011-01-01

    Automated Target Recognition (ATR) systems aim to automate target detection, recognition, and tracking. The current project applies a JPL ATR system to low resolution SONAR and camera videos taken from Unmanned Underwater Vehicles (UUVs). These SONAR images are inherently noisy and difficult to interpret, and pictures taken underwater are unreliable due to murkiness and inconsistent lighting. The ATR system breaks target recognition into three stages: 1) Videos of both SONAR and camera footage are broken into frames and preprocessed to enhance images and detect Regions of Interest (ROIs). 2) Features are extracted from these ROIs in preparation for classification. 3) ROIs are classified as true or false positives using a standard Neural Network based on the extracted features. Several preprocessing, feature extraction, and training methods are tested and discussed in this report.

  15. Field testing of a 3D automatic target recognition and pose estimation algorithm

    NASA Astrophysics Data System (ADS)

    Ruel, Stephane; English, Chad E.; Melo, Len; Berube, Andrew; Aikman, Doug; Deslauriers, Adam M.; Church, Philip M.; Maheux, Jean

    2004-09-01

    Neptec Design Group Ltd. has developed a 3D Automatic Target Recognition (ATR) and pose estimation technology demonstrator in partnership with the Canadian DND. The system prototype was deployed for field testing at Defence Research and Development Canada (DRDC)-Valcartier. This paper discusses the performance of the developed algorithm using 3D scans acquired with an imaging LIDAR. 3D models of civilian and military vehicles were built using scans acquired with a triangulation laser scanner. The models were then used to generate a knowledge base for the recognition algorithm. A commercial imaging LIDAR was used to acquire test scans of the target vehicles with varying range, pose and degree of occlusion. Recognition and pose estimation results are presented for at least 4 different poses of each vehicle at each test range. Results obtained with targets partially occluded by an artificial plane, vegetation and military camouflage netting are also presented. Finally, future operational considerations are discussed.

  16. Structural basis of diverse membrane target recognitions by ankyrins

    PubMed Central

    Wang, Chao; Wei, Zhiyi; Chen, Keyu; Ye, Fei; Yu, Cong; Bennett, Vann; Zhang, Mingjie

    2014-01-01

    Ankyrin adaptors together with their spectrin partners coordinate diverse ion channels and cell adhesion molecules within plasma membrane domains and thereby promote physiological activities including fast signaling in the heart and nervous system. Ankyrins specifically bind to numerous membrane targets through their 24 ankyrin repeats (ANK repeats), although the mechanism for the facile and independent evolution of these interactions has not been resolved. Here we report the structures of ANK repeats in complex with an inhibitory segment from the C-terminal regulatory domain and with a sodium channel Nav1.2 peptide, respectively, showing that the extended, extremely conserved inner groove spanning the entire ANK repeat solenoid contains multiple target binding sites capable of accommodating target proteins with very diverse sequences via combinatorial usage of these sites. These structures establish a framework for understanding the evolution of ankyrins' membrane targets, with implications for other proteins containing extended ANK repeat domains. DOI: http://dx.doi.org/10.7554/eLife.04353.001 PMID:25383926

  17. Target Site Recognition by a Diversity-Generating Retroelement

    PubMed Central

    Guo, Huatao; Tse, Longping V.; Nieh, Angela W.; Czornyj, Elizabeth; Williams, Steven; Oukil, Sabrina; Liu, Vincent B.; Miller, Jeff F.

    2011-01-01

    Diversity-generating retroelements (DGRs) are in vivo sequence diversification machines that are widely distributed in bacterial, phage, and plasmid genomes. They function to introduce vast amounts of targeted diversity into protein-encoding DNA sequences via mutagenic homing. Adenine residues are converted to random nucleotides in a retrotransposition process from a donor template repeat (TR) to a recipient variable repeat (VR). Using the Bordetella bacteriophage BPP-1 element as a prototype, we have characterized requirements for DGR target site function. Although sequences upstream of VR are dispensable, a 24 bp sequence immediately downstream of VR, which contains short inverted repeats, is required for efficient retrohoming. The inverted repeats form a hairpin or cruciform structure and mutational analysis demonstrated that, while the structure of the stem is important, its sequence can vary. In contrast, the loop has a sequence-dependent function. Structure-specific nuclease digestion confirmed the existence of a DNA hairpin/cruciform, and marker coconversion assays demonstrated that it influences the efficiency, but not the site of cDNA integration. Comparisons with other phage DGRs suggested that similar structures are a conserved feature of target sequences. Using a kanamycin resistance determinant as a reporter, we found that transplantation of the IMH and hairpin/cruciform-forming region was sufficient to target the DGR diversification machinery to a heterologous gene. In addition to furthering our understanding of DGR retrohoming, our results suggest that DGRs may provide unique tools for directed protein evolution via in vivo DNA diversification. PMID:22194701

  18. Target site recognition by a diversity-generating retroelement.

    PubMed

    Guo, Huatao; Tse, Longping V; Nieh, Angela W; Czornyj, Elizabeth; Williams, Steven; Oukil, Sabrina; Liu, Vincent B; Miller, Jeff F

    2011-12-01

    Diversity-generating retroelements (DGRs) are in vivo sequence diversification machines that are widely distributed in bacterial, phage, and plasmid genomes. They function to introduce vast amounts of targeted diversity into protein-encoding DNA sequences via mutagenic homing. Adenine residues are converted to random nucleotides in a retrotransposition process from a donor template repeat (TR) to a recipient variable repeat (VR). Using the Bordetella bacteriophage BPP-1 element as a prototype, we have characterized requirements for DGR target site function. Although sequences upstream of VR are dispensable, a 24 bp sequence immediately downstream of VR, which contains short inverted repeats, is required for efficient retrohoming. The inverted repeats form a hairpin or cruciform structure and mutational analysis demonstrated that, while the structure of the stem is important, its sequence can vary. In contrast, the loop has a sequence-dependent function. Structure-specific nuclease digestion confirmed the existence of a DNA hairpin/cruciform, and marker coconversion assays demonstrated that it influences the efficiency, but not the site of cDNA integration. Comparisons with other phage DGRs suggested that similar structures are a conserved feature of target sequences. Using a kanamycin resistance determinant as a reporter, we found that transplantation of the IMH and hairpin/cruciform-forming region was sufficient to target the DGR diversification machinery to a heterologous gene. In addition to furthering our understanding of DGR retrohoming, our results suggest that DGRs may provide unique tools for directed protein evolution via in vivo DNA diversification.

  19. An improved cortex-like neuromorphic system for target recognitions

    NASA Astrophysics Data System (ADS)

    Tsitiridis, Aristeidis; Yuen, Peter; Hong, Kan; Chen, Tong; Ibrahim, Izzati; Jackman, James; James, David; Richardson, Mark

    2010-10-01

    This paper reports on the enhancement of biologically-inspired machine vision through a rotation invariance mechanism. Research over the years has suggested that rotation invariance is one of the fundamental generic elements of object constancy, a known generic visual ability of the human brain. Cortex-like vision unlike conventional pixel based machine vision is achieved by mimicking neuromorphic mechanisms of the primates' brain. In this preliminary study, rotation invariance is implemented through histograms from Gabor features of an object. The performance of rotation invariance in the neuromorphic algorithm is assessed by the classification accuracies of a test data set which consists of image objects in five different orientations. It is found that a much more consistent classification result over these five different oriented data sets has been achieved by the integrated rotation invariance neuromorphic algorithm compared to the one without. In addition, the issue of varying aspect ratios of input images to these models is also addressed, in an attempt to create a robust algorithm against a wider variability of input data. The extension of the present achievement is to improve the recognition accuracies while incorporating it to a series of different real-world scenarios which would challenge the approach accordingly.

  20. Further analysis of picture interference when teaching word recognition to children with autism.

    PubMed

    Dittlinger, Laura Harper; Lerman, Dorothea C

    2011-01-01

    Previous research indicates that pairing pictures with associated words when teaching sight-word reading may hinder acquisition (e.g., Didden, Prinsen, & Sigafoos, 2000; Singh & Solman, 1990; Solman & Singh, 1992). The purpose of the current study was to determine whether this phenomenon was due to a previously learned association between the spoken word and picture (i.e., blocking) or due to the mere presence of a picture as an extrastimulus prompt (i.e., overshadowing). Three participants were taught to recognize words that were presented alone or paired with pictures that the participants either could or could not identify prior to training. All participants learned the words more quickly when they were presented alone rather than with pictures, regardless of their prior learning history with respect to pictures representing the words. This finding is consistent with the phenomenon of overshadowing. Nonetheless, consistent with blocking, all participants also acquired the words presented alone more quickly if they could not identify the associated pictures prior to training. Together, these findings have important implications for using prompts when teaching skills to individuals with developmental disabilities.