5,230 research outputs found
Phonological representations in dyslexia: nature, influences and development.
Developmental dyslexia is a specific difficulty in acquiring literacy skills that
manifests despite normal IQ, adequate educational opportunity and in the absence of
any obvious sensory or neurological damage. According to the Phonological
Representations Hypothesis a core deficit for individuals with dyslexia across
languages is a brain-based difficulty in accurately storing the sound sequences that
make up words, or 'phonological' representations.
In this thesis the Phonological Representation Hypothesis (PRH) of dyslexia
was tested and elaborated. Twenty-four dyslexic children alongside chronological age
and reading age matched groups were assessed over a three-year period.
Consistent with the PRH, associations were found between the quality of the
dyslexic children's phonological representations, as indexed by picture naming, and
their performance on related input and output phonological processing tasks based on
the same lexical items.
Possible reasons for the underspecificity of dyslexic phonological
representations were also investigated at cognitive and perceptual levels. The sensitivity
of dyslexic individuals to the presence of similar-sounding words within their mental
lexicon, 'phonological neighbourhood density', was assessed. Across a range of
phonological awareness tasks the dyslexic group were found to be as sensitive to this
lexical factor as their age peers.
Perception of amplitude envelope onsets (AEOs) was also investigated. AEOs
are an auditory parameter associated with speech rhythm and were hypothesised here to
be important for the establishment of well-specified phonological representations.
Dyslexic insensitivity to AEO variation was seen longitudinally through both
behavioural and neurophysiological assessment. These findings suggest that for some
dyslexic children perception of basic rhythmic speech cues may play a role in their
phonological representation deficit
The Impact of Culture-, Health- and Nature-Based Engagement on Mitigating the Adverse Effects of Public Health Restrictions on Wellbeing, Social Connectedness and Loneliness during COVID-19: Quantitative Evidence from a Smaller- and Larger-Scale UK Survey
Numerous UK surveys conducted during COVID-19 examined the pandemic’s detrimental effects on health, and the consequences of lockdown and other public health restrictions on mental health. Some surveys considered specific populations and social inequities exacerbated during COVID-19. Fewer surveys examined the ways in which the adverse effects of public health restrictions, such as lockdown, shielding and social distancing, might be alleviated. Drawing upon self-determination theory, the purpose of the current study was to assess whether culture-, health- and nature-based engagement would mitigate the effects of these restrictions on psychological wellbeing, social connectedness and loneliness. Quantitative data from a smaller-scale survey (n = 312) and a subset of questions embedded in a larger-scale survey (n = 3647) were analyzed using univariate and multivariate methods. Frequency of engagement, whether participation was online or offline and with or without other people, and the extent to which type of participation was associated with psychological wellbeing, social connectedness and loneliness were examined. Sports and fitness, gardening and reading occurred frequently in both surveys. For the smaller-scale survey, increases in connectedness and frequency of participation and decreases in loneliness were significantly associated with improved wellbeing, whereas the type of participation and age range were not significant predictors. Outcomes from the smaller-scale survey approximated the larger-scale survey for measures of loneliness, type and frequency of participation and proportion of respondents in each age range. As the frequency of participation was a significant predictor of wellbeing, but the type of participation was not significant, the findings implied that any type of participation in a sufficient quantity would be likely to boost wellbeing
The Underestimation Of Egocentric Distance: Evidence From Frontal Matching Tasks
There is controversy over the existence, nature, and cause of error in egocentric distance judgments. One proposal is that the systematic biases often found in explicit judgments of egocentric distance along the ground may be related to recently observed biases in the perceived declination of gaze (Durgin & Li, Attention, Perception, & Psychophysics, in press), To measure perceived egocentric distance nonverbally, observers in a field were asked to position themselves so that their distance from one of two experimenters was equal to the frontal distance between the experimenters. Observers placed themselves too far away, consistent with egocentric distance underestimation. A similar experiment was conducted with vertical frontal extents. Both experiments were replicated in panoramic virtual reality. Perceived egocentric distance was quantitatively consistent with angular bias in perceived gaze declination (1.5 gain). Finally, an exocentric distance-matching task was contrasted with a variant of the egocentric matching task. The egocentric matching data approximate a constant compression of perceived egocentric distance with a power function exponent of nearly 1; exocentric matches had an exponent of about 0.67. The divergent pattern between egocentric and exocentric matches suggests that they depend on different visual cues
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The UK Clinical Research Collaboration (UKCRC) Tissue Directory and Coordination Centre: the UK’s centre for facilitating the usage of human samples for medical research
The UKCRC Tissue Directory and Coordination Centre was established to improve access to and utilisation of UK human tissue samples for medical research. The key output of the Centre is the creation of the UK’s first pan-disease Tissue Directory (https://directory.biobankinguk.org/). Any researcher can search the Directory based on a series of simple key words including disease classification, age, sex, sample type, preservation details, quality indicators and datasets available. The Directory as of April 2017 contains 100 Bioresources. Researchers seeking fresh samples can also search for facilities that offer bespoke collection services. Future work of the Centre will be to explore greater standardisation of biobanking activities across the UK and to facilitate an inter-connected research infrastructure related to the use of human biosamples
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Developing a visual attention assessment for children at school entry
Whereas young children's visual attention has been explored in a number of previous studies, so far it has not been investigated by an assessment based on Bundesen's Theory of Visual Attention (TVA). TVA is a prominent visual attention model that has been widely used as foundation in studies targeting older children, adolescents or adults. In this paper we explore the utility of adopting TVA to explore the visual attention of 4- to 5- year olds and present the development of a simplified adapted version of a TVA-based assessment designed for this age group. Key assessment alterations included the substitution of letter stimuli with black and white symbols and the reduction of assessment duration. The suitability of the assessment for the target age group was subsequently tested in two consecutive studies (Study I: N = 43; Study II: N = 24). Study results show that measuring visual attention based on a simplified TVA-based assessment appears feasible in such a young age group, provided that the study design takes into account the capabilities of these young children. The authors argue that by adopting this kind of visual attention assessment the relationship between visual attention development and early learning could be better understood
Socioeconomic inequalities in vaccine uptake: A global umbrella review
This global umbrella review aimed to synthesise evidence of socioeconomic inequalities in the uptake of routine vaccinations and identify the mechanisms that may contribute to the association. To our knowledge, no attempt has been made to synthesise the global body of systematic reviews across a variety of vaccines, geographical locations, and measures of SES. The inclusion criteria were as follows: studies assessing vaccination uptake according to education, income, occupation/employment, and/or area-level deprivation; any country or universally recommended routine vaccination (according to the WHO); qualitative or quantitative reviews, published 2011-present. The searches were performed in eight databases. The screening process followed PRISMA-E guidelines, each stage was performed by one reviewer, and a 10% sample checked by a second for consistency. Included reviews underwent data extraction, quality appraisal (AMSTAR-2), and narrative synthesis according to country-context. After deduplication, 9,163 reports underwent title and abstract screening, leaving 119 full texts to be assessed for eligibility. Overall, 26 studies were included in the umbrella review. Evidence for lower uptake amongst disadvantaged SES individuals was found in all 26 reviews. However, 17 reviews showed mixed results, as inverse associations were also identified (lower uptake for advantaged SES, and/or higher uptake for disadvantaged SES). Those that explored high-income countries had a greater prevalence of mixed findings than those focusing on low/middle-income countries. The two most frequently cited mechanisms were vaccination knowledge, and confidence in vaccination or vaccination providers. These mechanisms were often understood by review authors as varying by level of education. We find socioeconomic differences in routine vaccination uptake, but the association did not always follow a gradient. Whilst education may be associated with uptake globally, our study indicates that its role varies by country-context. A limitation is the overlap of some primary studies across the included systematic reviews.10.1371/journal.pone.029468
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