Letter Strings Research Articles

Early Effect of Phonological Information in Korean Visual Word Recognition: An ERP Investigation with Transposed Letters.

The purpose of this study was to examine the role of phonological information on visual word recognition by using letter transposition effects. The Korean writing system gives a unique opportunity to investigate such phenomenon since the transposition of the beginning consonant (onset) and the end consonant (coda) of a certain syllable allows one to keep the coda phonology constant while changing the written alphabetic characters. In this study, 23 participants' ERPs to such transposition cases were compared with the ERPs to cases that do not maintain coda phonology while the participants were performing a go/no-go lexical decision task for visually presented letter strings. The results of the current study showed that transposed materials with original phonological information produce less N250 than both the baseline condition and the transposed materials with different phonological information condition. The results suggest that phonological information is used early in the lexical process in Korean and early orthographic processing is influenced by the characteristics of the grapheme to phoneme conversion process.

How acute stress may enhance subsequent memory for threat stimuli outside the focus of attention: DLPFC-amygdala decoupling

Stress-related disorders, e.g., anxiety and depression, are characterized by decreased top-down control for distracting information, as well as a memory bias for threatening information. However, it is unclear how acute stress biases mnemonic encoding and leads to prioritized storage of threat-related information even if outside the focus of attention. In the current study, healthy adults (N = 53, all male) were randomly assigned to stress induction using the socially evaluated cold-pressor test (SECPT) or a control condition. Participants performed a task in which they were required to identify a target letter within a string of letters that were either identical to the target and thereby facilitating detection (low distractor load) or mixed with other letters to complicate the search (high load). Either a fearful or neutral face was presented on the background, outside the focus of attention. Twenty-four hours later, participants were asked to perform a surprise recognition memory test for those background faces. Stress induction resulted in increased cortisol and negative subjective mood ratings. Stress did not affect visual search performance, however, participants in the stress group showed stronger memory compared to the control group for fearful faces in the low attentional load condition. Critically, the stress induced memory bias was accompanied by decoupling between amygdala and DLFPC during encoding, which may represent a mechanism for decreased ability to filter task-irrelevant threatening background information. The current study provides a potential neural account for how stress can produce a negative memory bias for threatening information even if presented outside the focus of attention. Despite of an adaptive advantage for survival, such tendencies may ultimately also lead to generalized fear, a possibility requiring additional investigation.

Stimulus orientation and the first-letter advantage

A post-cued partial report target-in-string identification experiment examined the influence of stimulus orientation on the serial position functions for strings of five consonants or five symbols, with an aim to test different accounts of the first-letter advantage observed in prior research. Under one account, this phenomenon is driven by processing that is specific to horizontally arranged letter (and digit) strings. An alternative account explains the first-letter advantage in terms of attentional biases towards the beginning of letter strings. We observed a significant three-way interaction between stimulus type (letters vs. symbols), serial position (1–5), and orientation (horizontal vs. vertical) that was driven by a greater first-position advantage for letters than symbols when stimuli were presented horizontally compared with vertical presentation. These results provide support for the letter-specific processing account of the first-letter advantage, and further suggest that differences in visual complexity between letters and symbols play a minor role. Nevertheless, a first-position advantage for letters was observed in the vertical presentation condition, thus pointing to some role for attentional biases that operate independently of string orientation.

Orthographic processing: A 'mid-level' vision of reading: The 44th Sir Frederic Bartlett Lecture.

I will describe how orthographic processing acts as a central interface between visual and linguistic processing during reading, and as such can be considered to be the 'mid-level vision' of reading research. In order to make this case, I first summarize the evidence in favour of letter-based word recognition before examining work investigating how orthographic similarities among words influence single word reading. I describe how evidence gradually accumulated against traditional measures of orthographic similarity and the associated theories of orthographic processing, forcing a reconsideration of how letter-position information is represented by skilled readers. Then, I present the theoretical framework that was developed to explain these findings, with a focus on the distinction between location-specific and location-invariant orthographic representations. Finally, I describe work extending this theoretical framework in two main directions: first, to the realm of reading development, with the aim to specify the key changes in the processing of letters and letter strings that accompany successful learning to read, and second, to the realm of sentence reading, in order to specify how orthographic information can be processed across several words in parallel, and how skilled readers keep track of which letters belong to which words.

Intraoperative floppy iris syndrome in cataract surgery

This discussion presents a self-comparable example type called T-design, a sort of measurable pseudo fractal repeating with critical interpretation evenness on a solitary discrete measurement (presently with a particular location calculation and programming THEME for Windows (see patternvision.com), which has permitted the revelation of various and complex collaboration designs in numerous sorts of human and creature communications just as in neuronal co operations inside living cerebrums. T-designs have additionally been distinguished in associations among robots and people and appear to be trademark for the structure of DNA and text. A meaning of T-designs is introduced just as the basics of the current location calculations and models. The possible significance of T-designs is at last delineated through an examination between human mass social orders and the mass social orders of proteins inside natural cells (in some cases called Cell City), where self-likeness of association developed more than billions of years is striking from nano to human scales dependent on self-comparable T-designs, however showing up in creatures in people just and dependent on hugely replicated normalized T-designed letter strings, for example, heavenly, lawful and logical writings. The innovation of composing and in this way a sturdy T-designed outside memory just two or three thousand years back – in a natural eye-squint - permitting socio-social memory to a great extent outer to cerebrums and along these lines the ascent of cutting edge science and innovation and the main enormous brained mass-social orders now totally dependent on T-designed strings. The relationship and self-closeness is hitting with the development of the simply instructive DNA T-designed strings by the RNA world, presently the DNA world.

Word and pseudoword superiority effects: Evidence from a shallow orthography language.

The word superiority effect (WSE) denotes better recognition of a letter embedded in a word rather than in a pseudoword. Along with WSE, also a pseudoword superiority effect (PSE) has been described: It is easier to recognise a letter in a legal pseudoword than in an unpronounceable nonword. At the current state of the art, both WSE and PSE have been mainly tested with English speakers. This study uses the Reicher-Wheeler paradigm with native speakers of Italian (a shallow orthography language). Different from English and French, we found WSE for reaction times (RTs) only, whereas PSE was significant for both accuracy and RTs. This finding indicates that in the Reicher-Wheeler task, readers of a shallow orthography language can effectively rely on both the lexical and the sublexical routes. As to the effect of letter position, a clear advantage for the first-letter position emerged, a finding suggesting a fine-grained processing of the letter strings with coding of letter position and indicating the role of visual acuity and crowding factors.

Do 'blacheap' and 'subcheap' both prime 'cheap'? An investigation of morphemic status and position in early visual word processing.

Much research suggests that words comprising more than one morpheme are decomposed into morphemes in the early stages of visual word recognition. In the present masked primed lexical decision study, we investigated whether or not decomposition occurs for both prefixed and suffixed nonwords and for nonwords which comprise a stem and a non-morphemic ending. Prime-target relatedness was manipulated in three ways: (1) primes shared a semantically transparent morphological relationship with the target (e.g., subcheap-CHEAP, cheapize-CHEAP); (2) primes comprised targets and non-affixal letter strings (e.g., blacheap-CHEAP, cheapstry-CHEAP); and (3) primes were real, complex words unrelated to the target (e.g., miscall-CHEAP, idealism-CHEAP). Both affixed and non-affixed nonwords significantly facilitated the recognition of their stem targets, suggesting that embedded stems are activated independently of whether they are accompanied by a real affix or a non-affix. There was no difference in priming between stems being embedded in initial and final string positions, indicating that embedded stem activation is position-independent. Finally, more priming was observed in the semantically interpretable affixed condition than in the non-affixed condition, which points to a semantic licensing mechanism during complex novel word processing.

Processing of emotional words in bilinguals: Testing the effects of word concreteness, task type and language status

The present study investigates whether the emotional content of words has the same effect in the different languages of bilinguals by testing the effects of word concreteness, the type of task used, and language status. Highly proficient bilinguals of Catalan and Spanish who learned Catalan and Spanish in early childhood in a bilingual immersion context, and who still live in such a context, performed an affective decision task (Experiment 1) and a lexical decision task (Experiment 2) in both Catalan and Spanish. A different set of Catalan–Spanish bilinguals, who were proficient in English and who learned English after early childhood in an instructional setting, performed a lexical decision task in both Spanish and English (Experiment 3). In both tasks administered throughout the experiments, the experimental stimuli were concrete and abstract words that varied in their emotional connotation (i.e. positive, negative and neutral words) and were presented in the two languages involved. In the affective decision task, participants decided if the words had emotional content or not, and in the lexical decision task they decided if the strings of letters were real words or not. The three experiments also included an unexpected free recall task. Results showed that the emotional content of words affected bilinguals’ performance in all three tasks. In particular, there was a disadvantage in processing for negative words in both the affective and lexical decision tasks, and an advantage for positive words in the lexical decision and free recall tasks. Importantly, language only interacted with the other variables in Experiment 3, suggesting that language status is a relevant factor in determining the extent to which emotional processing has the same characteristics in the two languages.

Elaborative feedback: Engaging reward and task-relevant brain regions promotes learning in pseudoword reading aloud.

Although much is known about the cognitive and neural basis of establishing letter-sound mappings in learning word forms, relatively little is known about what makes for the most effective feedback during this process. We sought to determine the neural basis by which elaborative feedback (EF), which contains both reward-related and content-specific information, may be more helpful than feedback containing only one kind of information (simple positive feedback, PF) or the other (content feedback, CF) in learning orthography-phonology (spelling-sound) mappings for novel letter strings. Compared to CF, EF activated the ventromedial prefrontal cortex, implicated in reward processing. Compared to PF, EF activated the posterior middle temporal, superior temporal, and supramarginal gyri-regions implicated in orthography-phonology conversion. In the same comparison, EF also activated the left fusiform gyrus/visual word form area-implicated in orthographic processing. Also EF, but not CF or PF, modulated activity in the caudate nucleus. In a postscan questionnaire, EF and PF were rated as more pleasant than CF, suggesting that modulation of the caudate for EF may be due to the coupling of reward and skill content. These findings suggest the enhanced effectiveness of EF may be due to concurrent activation of reward-related and task-relevant brain regions.

Two distinct parsing stages in nonword reading aloud: Evidence from Russian.

Word reading partly depends on the activation of sublexical letter clusters. Previous research has studied which types of letter clusters have psychological saliency, but less is known about cognitive mechanisms of letter string parsing. Here, we take advantage of the high degree of context-dependency of the Russian orthography to examine whether consonant-vowel (CV) clusters are treated as units in two stages of sublexical processing. In two experiments using a nonword reading task, we use two orthogonal manipulations: (a) insertion of a visual disruptor (#) to assess whether CV clusters are kept intact during the early visual parsing stage, and (b) presence of context-dependent grapheme-phoneme correspondences (GPCs; e.g., л[а] → /l/; л[я] → /lj/), to assess whether CV clusters remain intact or are split during the print-to-speech conversion stage. The results suggest that although CV clusters are initially processed as perceptual units in the early visual parsing stage, letters and not CV clusters drive print-to-speech conversion.

Semantic Ambiguity Effects in L2 Word Recognition.

The present study examined the ambiguity effects in second language (L2) word recognition. Previous studies on first language (L1) lexical processing have observed that ambiguous words are recognized faster and more accurately than unambiguous words on lexical decision tasks. In this research, L1 and L2 speakers of English were asked whether a letter string on a computer screen was an English word or not. An ambiguity advantage was found for both groups and greater ambiguity effects were found for the non-native speaker group when compared to the native speaker group. The findings imply that the larger ambiguity advantage for L2 processing is due to their slower response time in producing adequate feedback activation from the semantic level to the orthographic level.

Influence of script direction on word processing modes in left and right visual fields

ABSTRACTWord processing in left (LVF) and right (RVF) visual fields may be affected by left hemisphere activation during reading and by script direction. We evaluated the effect of script direction by presenting words in left-to-right (French) and right-to-left (Hebrew) scripts to bilingual French participants. Words of different lengths were presented in the LVF and the RVF in a naming task. Results showed (1) a stronger word length effect in the LVF than in the RVF in French, and no difference of word length effect between LVF and RVF in Hebrew; (2) a first-letter advantage only in the LVF in French and in the RVF in Hebrew, showing an effect of script direction on letter processing; and (3) a stronger advantage of external over internal letters in words presented in the LVF than in the RVF for both languages, showing a left hemisphere influence on letter activation. Thus, script direction and left hemisphere activation may affect different processes when reading words in LVF and RVF. Selective attention may orient and redistribute a processing “window” over the letter string according to script direction, and the modulation of attentional resources is influenced by left hemisphere activation.

The effect of orthographic depth on letter string processing: the case of visual attention span and rapid automatized naming

The present study investigated whether orthographic depth can increase the bias towards multi-letter processing in two reading-related skills: visual attention span (VAS) and rapid automatized naming (RAN). VAS (i.e., the number of visual elements that can be processed at once in a multi-element array) was tested with a visual 1-back task and RAN was measured in a serial letter naming task that introduced a novel manipulation (some letter sequences formed frequent words). Spanish-Basque and French-Basque bilingual children were tested at early (30 children in 1st and 2nd grade), and more advanced (24 children in 3rd, 4th and 5th grade) stages of reading acquisition to investigate whether they would be differently biased towards multi-letter processing due to reading in two shallow (Spanish, Basque), or a deep and a shallow (French, Basque) orthography. The French-Basque bilinguals, who read in a deep orthography, were expected to rely on larger orthographic units in reading and thus to be more biased towards multi-letter processing in both tasks. This was expected to be reflected by: (a) a uniform distribution of attention across letter strings in the VAS task, and (b) a greater interference of the embedded words on letter-by-letter naming in RAN, leading to longer naming times. The expected group differences were observed in the more advanced readers, with French-Basque bilinguals showing a wider distribution of VAS across letter strings and longer naming times in RAN.

PERCEPTUAL LOAD MANIPULATION DOES NOT REVEAL SENSITIVITY ON THE N170 ERP COMPONENT OF MANIPULATED FACES AND BODIES

Background: It has been controversial in the face recognition literaturę whether face-sensitive N170 is affected by selective attention. Attention was manipulated according to Lavie’s perceptual load theory, examining the effect of selective attention on the processing of faces and human bodies. Faces and human bodies were presented either intact or manipulated. Material/Methods: 18 Students (9Males) from Sohag University, aged between 19 and 22 years (M = 19.38, SD = 0.48) contributed data in this study. All participants were right handed, and had normal or corrected-to-normal visual acuity. Participants were instructed to detect specific letter strings „X or N” among different (i.e., High load), or identical (Low load) letters. Letters were superimposed on different distractors. Stimuli were presented intact (Exp.1), or manipulated (Exp.2-4), by removing certain features or parts in the face and body respectively. ERP technique was used and prominent N170 and LNC were measured. Results: It was found that there is no effect of selective attention on the face sensitive N170. It seems that cropped face N170 is not affected by selective attention. However, the N170 of faces and human bodies are not affected by selective attention. The LNC findings showed that this component is affected by selective attention with enhanced negativity under low load Conditions compared to high load conditions. Conclusions: The findings of the current study showed that either cropped faces and human bodies does not reveal sensitivity on the N170 ERP component of manipulated faces and bodies.

Perceived similarity between written Estonian and Finnish: Strings of letters or morphological units?

The distance or similarity between two languages can be objective or actual, i.e. discoverable by the tools and methods of linguists, or perceived by users of the languages. In this article two methods, the Levenshtein Distance (LD), which purports to measure the objective distance, and the Index of Perceived Similarity (IPS), which quantifies language users’ perceptions, are compared. The data are the quantitative results of a test measuring conscious perceptions of similarity between Estonian and Finnish inflectional morphology by Finnish and Estonian native speakers (‘Finns’ and ‘Estonians’) with no knowledge of and exposure to the other (‘target’) language. The results show that Finns see more similarity between Finnish and Estonian than Estonians do. Also the correlations between LD and the perception results of the Finns are statistically significant while the correlations between the LD and the IPS scores of the Estonians are not. Comments by test participants provide insights into the nature of the perceptions of similarity.

When birds and sias fly: A neural indicator of inferring a word meaning in context

Inference generation is a crucial skill in language comprehension. Recent research suggests that readers use both the contents from prior written text and their background knowledge, stored in long-term memory, to generate predictive inferences about what will come up next in a sentence. We recorded Event-Related Potentials (ERPs) to examine the reader's ability to make online inferences even in the presence of pseudowords (orthographically legal, but meaningless letter strings), that is, in the presence of referents with no a priori match to vocabulary stored knowledge. As expected, a large and sustained negativity (250–900ms) was elicited by the target word ‘fly’ when preceded by the pseudoword ‘Sias’ in the sentence ‘Sias fly.’ relative to when preceded by ‘Birds’ in the sentence ‘Birds fly’. However, when readers were provided with an initial statement inviting to make an inference: ‘Sias have wings’, the word ‘fly’ in ‘Sias fly’ only elicited a negative voltage deflection over 100ms period (250–350), rapidly falling down to baseline. This result indicates that participants rapidly generated online inferences even with a hindered access to a referent's meaning (i.e. not knowing what ‘Sias’ are). Remarkably, brainwave traces to the access to a word's meaning in long-term memory (access to a well-known fact such as ‘Birds fly’) only diverged from ERPs for an inferred-from-reading knowledge (‘Sias fly’) for 100ms. We conclude that a fundamental search for across sentence coherence drives fast inference making processes in reading tasks. This pattern of brain response is critical to understand the rapid acquisition of new vocabulary when learning first and second languages.

P 9 Uncoupling memory interaction during off-line consolidation: an fMRI study

Background This study focuses on the interaction of procedural and declarative memory contents and its effect on off-line consolidation over wakefulness on a neurophysiological level using fMRI. The finding that disconnecting declarative from implicit procedural motor contents allows off-line consolidation of motor performance over wakefulness but not over sleep ( Brown and Robertson, 2007 ) challenged the idea of separated memory systems ( Cohen and Squire, 1980 ) and lead to the assumption of an interaction during wakefulness but separation during sleep. Word-list learning for instance can uncouple declarative from procedural contents. We hypothesize, this results in diverging neuronal activity after off-line consolidation but no differences should occur, when keeping declarative and procedural aspects together. Methods Therefore, 65 healthy participants conducted a serial reaction time task (SRTT) as a procedural motor learning task in the morning immediately followed by one of four interference tasks or no further tasks (Rest) ( Fig. 1 ). The declarative verbal learning group (VL) learned a word-list consisting of 15 words, their control group (VLC) counted vowels in a nonsense letter string as a attention task based on verbal material. The declarative non-verbal learning group (NVL) played a kind of memory game with the appropriate control group counting squares in a cloud of triangles (NVLC). All participants repeated the SRTT ( Nissen and Bullemer, 1987 ) for a retest after 12 h investigating effects of memory systems” interaction. The SRTT has been conducted in a 3 T MRI scanner. Results In the verbal learning group the BOLD-Signal decreased from learning to testing in the ipsilateral cerebellum as well as in the supplementary motor area. In addition, we found an interaction between the verbal learning group and their appropriate control group and the rest group for BOLD-Signal within in these areas. No comparable effect was evident in the non-verbal groups. Discussion/conclusion Based on our results we ascribe a discharging effect on parts of the motor system to the uncoupling of declarative aspects from procedural learning by an interfering verbal learning task. This effect arose in the ipsilateral cerebellum as well as in the supplementary motor area.

Due diligence: revisiting the heat–aggression association hypothesis

ABSTRACTPrevious research has suggested that individuals hold cognitive associations between the constructs of hot temperatures and aggression. However, subsequent close replication attempts have cast doubt on the replicability of these effects. Therefore, the evidence for the existence of a cognitive heat–aggression association is mixed. A pilot study used a modified Affect Misattribution Procedure to examine whether exposure to heat-related words increased the accessibility of aggressive cognitions. The results of the pilot study showed that exposure to heat-related words increased the accessibility of aggressive cognitions relative to “comparison” trials (i.e. non-heat-related words and nonsense letter strings). I propose a direct replication of this pilot study, which will further test the existence of a heat–aggression association.

Letter and symbol identification: No evidence for letter-specific crowding mechanisms.

It has been proposed that letters, as opposed to symbols, trigger specialized crowding processes, boosting identification of the first and last letters of words. This hypothesis is based on evidence that single-letter accuracy as a function of within-string position has a W shape (the classic serial position function [SPF] in psycholinguistics) whereas an inverted V shape is obtained when measured with symbols. Our main goal was to test the robustness of the latter result. Our hypothesis was that any letter/symbol difference might result from short-term visual memory processes (due to the partial report [PR] procedures used in SPF studies) rather than from crowding. We therefore removed the involvement of short-term memory by precueing target-item position and compared SPFs with precueing and postcueing. Perimetric complexity was stringently matched between letters and symbols. In postcueing conditions similar to previous studies, we did not reproduce the inverted V shape for symbols: Clear-cut W shapes were observed with an overall smaller accuracy for symbols compared to letters. This letter/symbol difference was dramatically reduced in precueing conditions in keeping with our prediction. Our results are not consistent with the claim that letter strings trigger specialized crowding processes. We argue that PR procedures are not fit to isolate crowding processes.

Dynamic differences in letter contrast polarity improve peripheral letter string and word recognition performance

Dynamic differences in letter contrast polarity improve peripheral letter string and word recognition performance