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The development of speed discrimination abilities.
The processing of speed is a critical part of a child's visual development, allowing children to track and interact with moving objects. Despite such importance, no study has investigated the developmental trajectory of speed discrimination abilities or precisely when these abilities become adult-like. Here, we measured speed discrimination thresholds in 5-, 7-, 9-, 11-year-olds and adults using random dot stimuli with two different reference speeds (slow: 1.5 deg/s; fast: 6 deg/s). Sensitivity for both reference speeds improved exponentially with age and, at all ages, participants were more sensitive to the faster reference speed. However, sensitivity to slow speeds followed a more protracted developmental trajectory than that for faster speeds. Furthermore, sensitivity to the faster reference speed reached adult-like levels by 11 years, whereas sensitivity to the slower reference speed was not yet adult-like by this age. Different developmental trajectories may reflect distinct systems for processing fast and slow speeds. The reasonably late development of speed processing abilities may be due to inherent limits in the integration of neuronal responses in motion-sensitive areas in early childhood.
Individual differences in contextual facilitation: evidence from dyslexia and poor reading comprehension.
Ninety-two 7- to 10-year-old children read words presented in isolation or following a spoken sentence context. In absolute terms, poor readers showed more contextual facilitation than good readers. However, when the relative benefit of context was assessed, this was greater for children with better reading skills, and comprehension was a better predictor of contextual facilitation than decoding. Study 2 compared the performance of dyslexics with that of reading-age matched poor comprehenders and normal readers. The dyslexics showed greater contextual facilitation than the normal readers who, in turn, showed more priming than poor comprehenders. The results show that dyslexic children use context to compensate for poor decoding skills, whereas children with poor reading comprehension skills fail to benefit from context as much as normal readers.
Semantic processing and the development of word-recognition skills: Evidence from children with reading comprehension difficulties
Children with specific reading comprehension difficulties were compared with control children on tests of language skill. The two groups performed at a similar level on tests requiring predominantly phonological skills, but the poor comprehenders performed less well on tests tapping semantic ability. Although the two groups were matched for decoding ability (as assessed by nonword reading), the poor comprehenders were worse at reading words with irregular spelling patterns and low-frequency words. These results show that despite having adequate phonological decoding skills, poor comprehenders have problems reading words that are typically read with support from semantics. These findings are related to connectionist models of reading development in which phonological and semantic processes interact. © 1998 Academic Press.
Working memory deficits in poor comprehenders reflect underlying language impairments.
Three experiments assessed memory skills in good and poor comprehenders, matched for decoding skill. Experiments 1 and 2 investigated phonological and semantic contributions to short-term memory by comparing serial recall for words varying in length, lexicality, and concreteness. Poor comprehenders showed normal sensitivity to phonological manipulations (length and lexicality) but, consistent with their semantic weaknesses, their recall of abstract words was poor. Experiment 3 investigated verbal and spatial working memory. While poor comprehenders achieved normal spatial spans, their verbal spans were impaired. These results are discussed within a theoretical framework in which the memory difficulties associated with poor reading comprehension are specific to the verbal domain and are a concomitant of language impairment, rather than a cause of reading comprehension failure.
Developmental differences in sensitivity to semantic relations among good and poor comprehenders: evidence from semantic priming.
Semantic priming for category coordinates (e.g. CAT-DOG; AEROPLANE-TRAIN) and for pairs of words related through function (e.g. BROOM-FLOOR; SHAMPOO-HAIR) was assessed in children with good and poor reading comprehension, matched for decoding skill. Lexical association strength was also manipulated by comparing pairs of words that were highly associated with pairs that shared low association strength. Both groups of children showed priming for function-related words, but for the category co-ordinates, poor comprehenders only showed priming if the category pairs also shared high association strength. Good comprehenders showed priming for category-related targets, irrespective of the degree of prime-target association. These findings are related to models of language development in which category knowledge is gradually abstracted and refined from children's event-based knowledge and it is concluded that in the absence of explicit co-occurrence, poor comprehenders are less sensitive to abstract semantic relations than normal readers.
Segmentation, not rhyming, predicts early progress in learning to read.
We present a longitudinal study of children in the first 2 years of learning to read. A battery of tests of phonological skills administered when the children were prereaders identified two distinct and relatively independent factors, Rhyming (defined by measures of rhyme detection and rhyme production) and Segmentation (defined by measures of phoneme identification and phoneme deletion). Segmentation was strongly correlated with attainment in reading and spelling at the end of the first year at school, while Rhyming was not. In addition, letter name knowledge predicted both reading and spelling skill and showed an interactive effect with children's segmentation skills. By the end of the second year of school, however, rhyming had started to exert a predictive effect on spelling, but not on reading. The results are discussed in the context of current theories of the role of phonological skills in learning to read.
Segmentation does predict early progress in learning to read better than rhyme: A reply to Bryant
In our recent paper (Muter, Hulme, Snowling, & Taylor, 1997) we argued that measures of segmentation were better predictors of early progress in learning to read than were measures of rhyme. Bryant (1998, this issue), in his comment on our paper, has argued that this conclusion is flawed because the instructions used in our rhyme detection measure included the phrase "rhymes with or sounds like." We present new data showing that the instructions used do not have the effect Bryant claims: asking children which word "rhymes with" or which word "rhymes with or sounds like" a target word produces identical patterns of responses. We argue that Bryant's new measure derived from our data simply reflects children's global sensitivity to the similarity in sound between different words and that this measure provides no convincing support for his conclusion that sensitivity to onset and rime is a predictor of children's success in learning to read. We conclude that the data in our paper, as well as other recent evidence, support the view that measures of phonemic segmentation are better predictors of early reading skills than are measures of onset-rime sensitivity. © 1998 Academic Press.
Recommendations for the Nonpharmacological Treatment of Apathy in Brain Disorders
© 2019 American Association for Geriatric Psychiatry Apathy is a common neuropsychiatric syndrome observed across many neurocognitive and psychiatric disorders. Although there are currently no definitive standard therapies for the treatment of apathy, nonpharmacological treatment (NPT) is often considered to be at the forefront of clinical management. However, guidelines on how to select, prescribe, and administer NPT in clinical practice are lacking. Furthermore, although new Information and Communication Technologies (ICT) are beginning to be employed in NPT, their role is still unclear. The objective of the present work is to provide recommendations for the use of NPT for apathy, and to discuss the role of ICT in this domain, based on opinions gathered from experts in the field. The expert panel included 20 researchers and healthcare professionals working on brain disorders and apathy. Following a standard Delphi methodology, experts answered questions via several rounds of web-surveys, and then discussed the results in a plenary meeting. The experts suggested that NPT are useful to consider as therapy for people presenting with different neurocognitive and psychiatric diseases at all stages, with evidence of apathy across domains. The presence of a therapist and/or a caregiver is important in delivering NPT effectively, but parts of the treatment may be performed by the patient alone. NPT can be delivered both in clinical settings and at home. However, while remote treatment delivery may be cost and time-effective, it should be considered with caution, and tailored based on the patient's cognitive and physical profile and living conditions.
Dynamic sustained attention markers differentiate atypical development: The case of Williams syndrome and Down's syndrome.
Impaired sustained attention is considered an important factor in determining poor functional outcomes across multiple cognitive and behavioural disorders. Sustained attention is compromised for both children with Williams syndrome (WS) and Down's syndrome (DS), but specific difficulties remain poorly understood because of limitations in how sustained attention has been assessed thus far. In the current study, we compared the performance of typically developing children (N = 99), children with WS (N = 25), and children with DS (N = 18), on a Continuous Performance Task - a standard tool for measuring sustained attention. In contrast to previous studies, primarily focused on overall differences in mean performance, we estimated the extent to which performance changed over time on task, thus focusing directly on the sustained element of performance. Children with WS and children with DS performed more poorly overall compared to typically developing children. Importantly, measures specific to changes over time differentiated between children with the two syndromes. Children with WS showed a decrement in performance, whereas children with Down's syndrome demonstrated non-specific poor performance. In addition, our measure of change in performance predicted teacher-rated attention deficits symptoms across the full sample. An approach that captures dynamic changes in performance over assessments may be fruitful for investigating similarities and differences in sustained attention for other atypically developing populations.
Establishing boundary conditions for multiple design elements congruent with taste expectations
© 2019 Elsevier Ltd Over the past two decades, a burgeoning literature has demonstrated the robust associations that exist between visual elements (‘cues’) on product packaging in the food and beverage category and consumer expectations regarding the taste of a product. However, to date, little research has examined if/how the individual effects demonstrated for such visual cues combine when multiple cues are presented together. Therefore, two experiments were designed to investigate whether manipulating the number (Experiment 1), and congruency (i.e., an association with a particular taste as identified by previous literature; Experiment 2) of word, colour, and background pattern angularity cues would influence people's taste expectations and associated evaluations. The results of Experiment 1 demonstrated that increasing the number of congruent cues on product packaging increased the strength of people's expectations concerning the relevant basic taste, with an apparent ‘ceiling effect’ hinted at. Experiment 2 extended this novel empirical finding by demonstrating that when colour and background pattern cues were associated with different basic tastes (i.e., the cues were, in some sense, ‘incongruent’), rather than counteracting one another, colour tended to dominate over background pattern in terms of determining the expected taste of the product. Taken together, these results suggest that stronger, or at least more salient, design cues dominate over weaker ones when they conflict in terms of their meaning (or corresponding taste).