scholarly journals Disrupted Spatial Organization of Cued Exogenous Attention Persists Into Adulthood in Developmental Dyslexia

2021 ◽  
Vol 12 ◽  
Author(s):  
Ana Pina Rodrigues ◽  
Miguel Castelo-Branco ◽  
Marieke van Asselen
Keyword(s):  
Spatial Distribution ◽  
Developmental Dyslexia ◽  
Spatial Organization ◽  
Response Times ◽  
Exogenous Attention ◽  
Similar Response ◽  
Reading Impairment ◽  
Attention Orienting ◽  
The Neural Network ◽  
Attentional Engagement

Purpose: Abnormal exogenous attention orienting and diffused spatial distribution of attention have been associated with reading impairment in children with developmental dyslexia. However, studies in adults have failed to replicate such relationships. The goal of the present study was to address this issue by assessing exogenous visual attention and its peripheral spatial distribution in adults with developmental dyslexia.Methods: We measured response times, accuracy and eye movements of 18 dyslexics and 19 typical readers in a cued discrimination paradigm, in which stimuli were presented at different peripheral eccentricities.Results: Results showed that adults with developmental dyslexia were slower that controls in using their mechanisms of exogenous attention orienting. Moreover, we found that while controls became slower with the increase of eccentricity, dyslexics showed an abnormal inflection at 10° as well as similar response times at the most distant eccentricities. Finally, dyslexics show attentional facilitation deficits above 12° of eccentricity, suggesting an attentional engagement deficit at far periphery.Conclusion: Taken together, our findings indicate that, in dyslexia, the temporal deficits in orientation of attention and its abnormal peripheral spatial distribution are not restricted to childhood and persist into adulthood. Our results are, therefore, consistent with the hypothesis that the neural network underlying selective spatial attention is disrupted in dyslexia.

Does Viotin Activate Violin More Than Viocin?

2014 ◽  
Vol 61 (1) ◽  
pp. 23-29 ◽  
Author(s):  
Manuel Perea ◽  
Victoria Panadero
Keyword(s):  
Word Recognition ◽  
Visual Word Recognition ◽  
Developmental Dyslexia ◽  
Computational Models ◽  
Error Rates ◽  
Visual Word ◽  
Base Word ◽  
Similar Response ◽  
Skilled Readers ◽  
Young Readers

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.

Accuracy and Speed of Orthographic Processing in Persons with Developmental Dyslexia

2005 ◽  
Vol 101 (1) ◽  
pp. 95-107 ◽  
Author(s):  
Wayne M. King ◽  
Linda L. Lombardino ◽  
Sarah Ahmed
Keyword(s):  
Developmental Dyslexia ◽  
Word Reading ◽  
Response Times ◽  
Age Groups ◽  
Group Differences ◽  
Control Group ◽  
Age Difference ◽  
Significant Difference ◽  
Typically Achieving ◽  
Reading Disabled

A group of 39 persons (20 male and 19 female, 11.0 to 32.5 yr.) with developmental dyslexia and 42 controls (21 male and 21 female, 11.2 to 32.3 years) were compared on computerized tests of sight word reading, nonword decoding, and spelling recognition. The subjects with developmental dyslexia performed significantly slower and less accurately than controls on all tasks. Further, the effect size of the group differences was larger for the older group. Within-group analyses showed a significant difference by age group on accuracy. Only the control group showed a significant age difference between groups on response time. Mean accuracy and response times for the reading-disabled subjects resembled shifted versions of the control group means. These results agree with previous reports that phonological deficits persist for reading-disabled adults and suggest a test of whether the discrepancy between reading-disabled and typically achieving readers may actually increase across age groups.

scholarly journals Aesthetic appreciation of musical intervals enhances behavioural and neurophysiological indexes of attentional engagement and motor inhibition

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
P. Sarasso ◽  
I. Ronga ◽  
A. Pistis ◽  
E. Forte ◽  
F. Garbarini ◽  
...  
Keyword(s):  
Response Times ◽  
Indirect Evidence ◽  
Detection Task ◽  
Auditory Evoked Potential ◽  
Motor Behaviour ◽  
Motor Inhibition ◽  
Aesthetic Appreciation ◽  
Aesthetic Judgement ◽  
Research Areas ◽  
Attentional Engagement

AbstractFrom Kant to current perspectives in neuroaesthetics, the experience of beauty has been described as disinterested, i.e. focusing on the stimulus perceptual features while neglecting self-referred concerns. At a neurophysiological level, some indirect evidence suggests that disinterested aesthetic appreciation might be associated with attentional enhancement and inhibition of motor behaviour. To test this hypothesis, we performed three auditory-evoked potential experiments, employing consonant and dissonant two-note musical intervals. Twenty-two volunteers judged the beauty of intervals (Aesthetic Judgement task) or responded to them as fast as possible (Detection task). In a third Go-NoGo task, a different group of twenty-two participants had to refrain from responding when hearing intervals. Individual aesthetic judgements positively correlated with response times in the Detection task, with slower motor responses for more appreciated intervals. Electrophysiological indexes of attentional engagement (N1/P2) and motor inhibition (N2/P3) were enhanced for more appreciated intervals. These findings represent the first experimental evidence confirming the disinterested interest hypothesis and may have important applications in research areas studying the effects of stimulus features on learning and motor behaviour.

Intelligent Interactive Visual Exploration of Temporal Associations among Multiple Time-oriented Patient Records

2009 ◽  
Vol 48 (03) ◽  
pp. 254-262 ◽  
Author(s):  
Y. Shahar ◽  
M. Taieb-Maimon ◽  
D. Klimov
Keyword(s):  
Response Times ◽  
Visual Exploration ◽  
Interactive System ◽  
Temporal Association ◽  
Multiple Time ◽  
Similar Response ◽  
Patient Records ◽  
Knowledge Based ◽  
Significant Difference ◽  
Similar Accuracy

Summary Objectives: To design, implement and evaluate the functionality and usability of a methodology and a tool for interactive exploration of time and value associations among multiple-patient longitudinal data and among meaningful concepts derivable from these data. Methods: We developed a new, user-driven, interactive knowledge-based visualization technique, called Temporal Association Charts (TACs). TACs support the investigation of temporal and statistical associations within multiple patient records among both con cepts and the temporal abstractions derived from them. The TAC methodology was implemented as part of an interactive system, called VISITORS, which supports intelligent visualization and exploration of longitudinal patient data. The TAC module was evaluated for functionality and usability by a group of ten users, five clinicians and five medical informaticians. Users were asked to answer ten questions using the VISITORS system, five of which required the use of TACs. Results: Both types of users were able to answer the questions in reasonably short periods of time (a mean of 2.5 ± 0.27 minutes) and with high accuracy (95.3 ± 4.5 on a 0–100 scale), without a significant difference between the two groups. All five questions requiring the use of TACs were answered with similar response times and accuracy levels. Similar accuracy scores were achieved for questions requiring the use of TACs and for questions requiring the use only of general exploration operators. However, response times when using TACs were slightly longer. Conclusions: TACs are functional and usable. Their use results in a uniform performance level, regardless of the type of clinical question or user group involved.

scholarly journals Linking Spatial Structure and Community-Level Biotic Interactions through Cooccurrence and Time Series Modeling of the Human Intestinal Microbiota

mSystems ◽  
2017 ◽  
Vol 2 (5) ◽  
Author(s):  
Eric J. de Muinck ◽  
Knut E. A. Lundin ◽  
Pål Trosvik
Keyword(s):  
Spatial Distribution ◽  
Spatial Structure ◽  
Gut Microbiome ◽  
Spatial Organization ◽  
Biotic Interactions ◽  
Community Level ◽  
Human Gut ◽  
Microbial Composition ◽  
Fecal Samples ◽  
Human Gut Microbiome

ABSTRACT The human gut microbiome is the subject of intense study due to its importance in health and disease. The majority of these studies have been based on the analysis of feces. However, little is known about how the microbial composition in fecal samples relates to the spatial distribution of microbial taxa along the gastrointestinal tract. By characterizing the microbial content both in intestinal tissue samples and in fecal samples obtained daily, we provide a conceptual framework for how the spatial structure relates to biotic interactions on the community level. We further describe general categories of spatial distribution patterns and identify taxa conforming to these categories. To our knowledge, this is the first study combining spatial and temporal analyses of the human gut microbiome. This type of analysis can be used for identifying candidate probiotics and designing strategies for clinical intervention. The gastrointestinal (GI) microbiome is a densely populated ecosystem where dynamics are determined by interactions between microbial community members, as well as host factors. The spatial organization of this system is thought to be important in human health, yet this aspect of our resident microbiome is still poorly understood. In this study, we report significant spatial structure of the GI microbiota, and we identify general categories of spatial patterning in the distribution of microbial taxa along a healthy human GI tract. We further estimate the biotic interaction structure in the GI microbiota, both through time series and cooccurrence modeling of microbial community data derived from a large number of sequentially collected fecal samples. Comparison of these two approaches showed that species pairs involved in significant negative interactions had strong positive contemporaneous correlations and vice versa, while for species pairs without significant interactions, contemporaneous correlations were distributed around zero. We observed similar patterns when comparing these models to the spatial correlations between taxa identified in the adherent microbiota. This suggests that colocalization of microbial taxon pairs, and thus the spatial organization of the GI microbiota, is driven, at least in part, by direct or indirect biotic interactions. Thus, our study can provide a basis for an ecological interpretation of the biogeography of the human gut. IMPORTANCE The human gut microbiome is the subject of intense study due to its importance in health and disease. The majority of these studies have been based on the analysis of feces. However, little is known about how the microbial composition in fecal samples relates to the spatial distribution of microbial taxa along the gastrointestinal tract. By characterizing the microbial content both in intestinal tissue samples and in fecal samples obtained daily, we provide a conceptual framework for how the spatial structure relates to biotic interactions on the community level. We further describe general categories of spatial distribution patterns and identify taxa conforming to these categories. To our knowledge, this is the first study combining spatial and temporal analyses of the human gut microbiome. This type of analysis can be used for identifying candidate probiotics and designing strategies for clinical intervention. Author Video: An author video summary of this article is available.

Flicker Masking and Developmental Dyslexia

Perception ◽  
1986 ◽  
Vol 15 (4) ◽  
pp. 473-482 ◽  
Author(s):  
Andrew T Smith ◽  
Frances Early ◽  
Sarah C Grogan
Keyword(s):  
Spatial Frequency ◽  
Visual System ◽  
Developmental Dyslexia ◽  
Cell Function ◽  
Cell Activity ◽  
Reaction Times ◽  
Visual Persistence ◽  
Reading Impairment ◽  
Spatial Frequencies

Recent studies have provided evidence that dyslexic children tend to show longer visual persistence than control children when presented with low-spatial-frequency grating stimuli. The possibility that this phenomenon might reflect an impairment of inhibitory Y-cell activity in the visual system of dyslexics has been investigated. A flicker masking technique was used to mask Y-cell activity selectively in a group of dyslexic boys and a group of age-matched controls. There were no overall differences in reaction times to the offsets of grating patterns of various spatial frequencies between the groups, and no differences between subgroups defined by age, degree of reading impairment, or any other criterion. The results show no evidence of abnormal Y-cell function in developmental dyslexia.

Effects of Repetition of Display Components on the Latency of Multiple Reports of Congruence

1971 ◽  
Vol 23 (1) ◽  
pp. 82-96
Author(s):  
Philip H. K. Seymour
Keyword(s):  
Response Times ◽  
Similar Response ◽  
Slow Response ◽  
Word Shape

Subjects gave grouped multiple reports of the congruence of each member of arrays of one, two or three word-shape or shape-shape pairs, and a measure was taken of the time elapsing between onset of the array and initiation of a multiple yes/no report. Double and triple reports were initiated less rapidly than single reports. Replicated arrays, involving repetition of a display pair, gave similar response times for double and triple reports, and were classified faster than non-replicated arrays requiring the same over report. In the case of non-replicated arrays triple reports were initiated less rapidly than double reports. Both classes of array showed substantial effects for congruence, giving slow response times where all pairs in the array were incongruent or where the lefthand or first reported display was incongruent.

Spatial distribution of excitatory and inhibitory synapses on a Purkinje cell in a rat cerebellar culture

1993 ◽  
Vol 70 (4) ◽  
pp. 1316-1325 ◽  
Author(s):  
T. Hirano ◽  
K. Kasono
Keyword(s):  
Spatial Distribution ◽  
Purkinje Cell ◽  
Purkinje Cells ◽  
Spatial Organization ◽  
Lucifer Yellow ◽  
Inhibitory Synapses ◽  
Presynaptic Neuron ◽  
Presynaptic Terminals ◽  
Excitatory And Inhibitory Synapses

1. The spatial distribution of excitatory and inhibitory synapses on cultured Purkinje cells was studied with fluorescence, scanning electron microscopy (SEM), and electrophysiological techniques. 2. Presynaptic terminals were identified with immunohistochemical staining of synaptophysin and the results were correlated with SEM micrographs. 3. Excitatory and inhibitory inputs onto the Purkinje cell were identified from the direction and pharmacology of the postsynaptic current. 4. The localization of the presynaptic terminals on the Purkinje cell was observed after electrophysiological identification by filling the presynaptic neuron with Lucifer yellow and the Purkinje cell with Texas red. 5. The axon and presynaptic terminals of excitatory and inhibitory inputs had a different spatial organization. Excitatory inputs from granule cells were exclusively localized on the dendrites of Purkinje cells, whereas inhibitory contacts were found on both the soma and dendrites. This result is similar to that described in vivo.

scholarly journals The Omission of Accent Marks Does Not Hinder Word Recognition: Evidence From Spanish

2021 ◽  
Vol 12 ◽  
Author(s):  
Ana Marcet ◽  
María Fernández-López ◽  
Melanie Labusch ◽  
Manuel Perea
Keyword(s):  
Word Recognition ◽  
Lexical Decision ◽  
Lexical Decision Task ◽  
Response Times ◽  
Word Identification ◽  
Decision Task ◽  
Similar Response ◽  
Opposite Pattern ◽  
Semantic Categorization ◽  
Blocked Design

Recent research has found that the omission of accent marks in Spanish does not produce slower word identification times in go/no-go lexical decision and semantic categorization tasks [e.g., cárcel (prison) = carcel], thus suggesting that vowels like á and a are represented by the same orthographic units during word recognition and reading. However, there is a discrepant finding with the yes/no lexical decision task, where the words with the omitted accent mark produced longer response times than the words with the accent mark. In Experiment 1, we examined this discrepant finding by running a yes/no lexical decision experiment comparing the effects for words and non-words. Results showed slower response times for the words with omitted accent mark than for those with the accent mark present (e.g., cárcel < carcel). Critically, we found the opposite pattern for non-words: response times were longer for the non-words with accent marks (e.g., cárdil > cardil), thus suggesting a bias toward a “word” response for accented items in the yes/no lexical decision task. To test this interpretation, Experiment 2 used the same stimuli with a blocked design (i.e., accent mark present vs. omitted in all items) and a go/no-go lexical decision task (i.e., respond only to “words”). Results showed similar response times to words regardless of whether the accent mark was omitted (e.g., cárcel = carcel). This pattern strongly suggests that the longer response times to words with an omitted accent mark in yes/no lexical decision experiments are a task-dependent effect rather than a genuine reading cost.

Sign in / Sign up

Export Citation Format

Share Document