Developmental Dyslexia Peterson, Robin L; Pennington, Bruce F
Annual review of clinical psychology,
03/2015, Volume:
11, Issue:
1
Journal Article
Peer reviewed
This review uses a levels-of-analysis framework to summarize the current understanding of developmental dyslexia's etiology, brain bases, neuropsychology, and social context. Dyslexia is caused by ...multiple genetic and environmental risk factors as well as their interplay. Several candidate genes have been identified in the past decade. At the brain level, dyslexia is associated with aberrant structure and function, particularly in left hemisphere reading language networks. The neurocognitive influences on dyslexia are also multifactorial and involve phonological processing deficits as well as weaknesses in other oral language skills and processing speed. We address contextual issues such as how dyslexia manifests across languages and social classes as well as what treatments are best supported. Throughout the review, we highlight exciting new research that cuts across levels of analysis. Such work promises eventually to provide a comprehensive explanation of the disorder as well as its prevention and remediation.
Developmental dyslexia Peterson, Robin L, PhD; Pennington, Bruce F, PhD
The Lancet,
05/2012, Volume:
379, Issue:
9830
Journal Article
Peer reviewed
Open access
Summary Dyslexia is a neurodevelopmental disorder that is characterised by slow and inaccurate word recognition. Dyslexia has been reported in every culture studied, and mounting evidence draws ...attention to cross-linguistic similarity in its neurobiological and neurocognitive bases. Much progress has been made across research specialties spanning the behavioural, neuropsychological, neurobiological, and causal levels of analysis in the past 5 years. From a neuropsychological perspective, the phonological theory remains the most compelling, although phonological problems also interact with other cognitive risk factors. Work confirms that, neurobiologically, dyslexia is characterised by dysfunction of the normal left hemisphere language network and also implicates abnormal white matter development. Studies accounting for reading experience demonstrate that many recorded neural differences show causes rather than effects of dyslexia. Six predisposing candidate genes have been identified, and evidence shows gene by environment interaction.
The multiple deficit model (MDM) was proposed because the prevailing single deficit model provided an inadequate account of atypical neuropsychological development. Across methods and levels of ...analysis, there has been support for the two fundamental tenets of the MDM, that multiple predictors contribute probabilistically to neurodevelopmental disorders and shared risk factors contribute to comorbidity. Diagnostically, the multiplicity of factors means that no single cognitive deficit or combination of deficits can be used to rule in or out most neurodevelopmental disorders. Challenges for the MDM are that the theory is difficult to falsify and that current cross-sectional studies cannot establish causality. Prospects for further development of the MDM include incorporating an explicit focus on promotive and protective factors and pursuing mechanistic connections between multiple factors across levels of analysis.
Explaining the sex difference in dyslexia Arnett, Anne B.; Pennington, Bruce F.; Peterson, Robin L. ...
Journal of child psychology and psychiatry,
June 2017, Volume:
58, Issue:
6
Journal Article
Peer reviewed
Open access
Background
Males are diagnosed with dyslexia more frequently than females, even in epidemiological samples. This may be explained by greater variance in males’ reading performance.
Methods
We expand ...on previous research by rigorously testing the variance difference theory, and testing for mediation of the sex difference by cognitive correlates. We developed an analytic framework that can be applied to group differences in any psychiatric disorder.
Results
Males’ overrepresentation in the low performance tail of the reading distribution was accounted for by mean and variance differences across sex. There was no sex difference at the high performance tail. Processing speed (PS) and inhibitory control partially mediated the sex difference. Verbal reasoning emerged as a strength in males.
Conclusions
Our results complement a previous finding that PS partially mediates the sex difference in symptoms of attention deficit/hyperactivity disorder (ADHD), and helps explain the sex difference in both dyslexia and ADHD and their comorbidity.
Pediatric mild traumatic brain injuries (mTBIs) represent an evolving field of interest in youth athletics. Although most players recover within 4 weeks, some have symptoms that last longer. Little ...is known about youth health-related quality of life (HRQoL) after mTBI.
To characterize youth HRQoL after soccer-related mTBI and to identify predictors of individual differences in HRQoL recovery.
Prospective cohort study.
Youth soccer.
Soccer players, aged 8 to 17 years, who sustained an mTBI (n = 23) or orthopaedic injury (OI, n = 24) or remained uninjured (n = 23) during a single season.
We assessed HRQoL via the Pediatric Quality of Life Inventory, version 4.0, and postconcussive symptoms via the Health and Behavior Index. Serial assessments occurred at 24 to 48 hours, 7 days, 30 days, and 90 days postinjury via telephone interview.
At 7 days postinjury, the mTBI and OI groups had poorer total HRQoL (F2,67 = 11.35, P < .001) than the uninjured control group. At 7 days, the mTBI group had the poorest psychosocial HRQoL, whereas the OI group had the poorest physical HRQoL. Differences between the mTBI and uninjured control groups resolved by 30 days. Within the mTBI group, players with significant postconcussive symptoms at 7 days had poorer total (F1,21 = 23.071, P ≤ .001; F1,21 = 5.798, P = .028), psychosocial (F1,21 = 16.488, P = < .001; F1,21 = 5.050, P = .039), and physical (F1,21 = 21.671, P = < .001; F1,21 = 5.119, P = .038) HRQoL at 7 and 30 days, respectively, than players with minimal symptoms; these differences resolved by 90 days.
As a group, youth soccer players who sustained mTBI had transient impairments in HRQoL that resolved by 30 days. A subset of players with significant postconcussive symptoms at 7 days postinjury had poorer HRQoL for at least 30 days postinjury than those whose postconcussive symptoms had resolved within a week of injury. This suggests ongoing recovery in this subset at 30 days and the potential utility of HRQoL as a measure of recovery.
Purpose: Speech sound disorder (SSD) in conjunction with a language disorder has been associated with poor literacy acquisition; however, no study has evaluated whether articulation, phonological, or ...sequencing skills are differentially related to reading skills. Therefore, this study examined the relationship between speech error types at ages 5-6 years and literacy at ages 7-9 years. Phonological errors were hypothesized to predict phonological awareness (PA) and literacy even while accounting for other speech error types and language skills. Method: One hundred twenty-three children, 86 with a history of speech impairment, completed a battery of speech, language, and literacy tests at ages 5-6 years and again at ages 7-9 years. Speech production at ages 5-6 years was analyzed, and indices of articulation errors, phonological errors, and sequencing deficits were obtained. The relationships of these error types to concurrent language and preliteracy skills and to later literacy outcomes were assessed. Results: As expected, phonological, but not articulation, errors at ages 5-6 years predicted concurrent PA and letter knowledge, as well as literacy at ages 7-9 years, even while accounting for language skills. Surprisingly, of all the error types, sequencing deficits showed the strongest relationship with PA (ages 5-6 years) and literacy (ages 7-9 years). Conclusions: These results suggest that some components of SSD uniquely predict preliteracy and literacy skills, even when controlling for language ability. Future investigations should examine further the association between sequencing deficits and literacy skills, test whether observed relationships hold at younger ages, and evaluate the efficacy of integrating literacy interventions into speech therapy to reduce later reading difficulties.
The perception and response to cellular death is an important aspect of multicellular eukaryotic life. For example, damage-associated molecular patterns activate an inflammatory cascade that leads to ...removal of cellular debris and promotion of healing. We demonstrate that lysis of Pseudomonas aeruginosa cells triggers a program in the remaining population that confers fitness in interspecies co-culture. We find that this program, termed P. aeruginosa response to antagonism (PARA), involves rapid deployment of antibacterial factors and is mediated by the Gac/Rsm global regulatory pathway. Type VI secretion, and, unexpectedly, conjugative type IV secretion within competing bacteria, induce P. aeruginosa lysis and activate PARA, thus providing a mechanism for the enhanced capacity of P. aeruginosa to target bacteria that elaborate these factors. Our finding that bacteria sense damaged kin and respond via a widely distributed pathway to mount a complex response raises the possibility that danger sensing is an evolutionarily conserved process.
Previous research has established that learning to read improves children's performance on reading‐related phonological tasks, including phoneme awareness (PA) and nonword repetition. Few studies ...have investigated whether literacy acquisition also promotes children's rapid automatized naming (RAN). We tested the hypothesis that literacy acquisition should influence RAN in an international, longitudinal population sample of twins. Cross‐lagged path models evaluated the relationships among literacy, PA, and RAN across four time points from pre‐kindergarten through grade 4. Consistent with previous research, literacy showed bidirectional relationships with reading‐related oral language skills. We found novel evidence for an effect of earlier literacy on later RAN, which was most evident in children at early phases of literacy development. In contrast, the influence of earlier RAN on later literacy was predominant among older children. These findings imply that the association between these two related skills is moderated by development. Implications for models of reading development and for dyslexia research are discussed.
Literacy acquisition showed reciprocal effects with both rapid automatized naming and phonological awareness an international longitudinal twin sample. The influence of earlier literacy on later rapid automatized naming was most evident in the early phases of literacy development.
The current study tested a multiple-cognitive predictor model of word reading, math ability, and attention in a community-based sample of twins ages 8 to 16 years (N = 636). The objective was to ...identify cognitive predictors unique to each skill domain as well as cognitive predictors shared among skills that could help explain their overlap and thus help illuminate the basis for comorbidity of related disorders (reading disability, math disability, and attention deficit hyperactivity disorder). Results indicated that processing speed contributes to the overlap between reading and attention as well as math and attention, whereas verbal comprehension contributes to the overlap between reading and math. There was no evidence that executive functioning skills help account for covariation among these skill domains. Instead, specific executive functions differentially related to certain outcomes (i.e., working memory to math and inhibition to attention). We explored whether the model varied in younger versus older children and found only minor differences. Results are interpreted within the context of the multiple deficit framework for neurodevelopmental disorders.
Context Pediatric mild traumatic brain injuries (mTBI) represent an evolving field of interest in youth athletics. While most players recover within 4 weeks, some have symptoms that last longer. ...Little is known about youth health-related quality of life (HRQoL) following mTBI. Objective To characterize youth HRQoL following soccer-related mTBI and to identify predictors of individual differences in HRQoL recovery. Design Prospective cohort study Setting Youth Soccer Participants Soccer players, ages 8–17 years, who sustained mTBI (n=23), orthopedic injuries (OI, n=24), or remained uninjured (n=23) during a single season. Main Outcome Measures HRQoL was assessed via the Pediatric Quality of Life Version 4.0 and post-concussive symptomatology via the Health and Behavior Index. Serial assessments occurred at 24–48 hours, 7 days, 30 days and 90 days post-injury via telephone interview. Results Seven days post-injury, the mTBI and OI groups had poorer Total HRQoL (F2,67 =11.35, p<0.001) than uninjured controls. At 7 days, the mTBI group had the poorest Psychosocial HRQoL, while OI had the poorest Physical HRQoL. Differences between the mTBI group and uninjured controls resolved by 30 days. Within the mTBI group, players with significant post-concussive symptoms at 7 days had poorer Total (F1,21=23.071, p<=0.001; F1,21=5.798, p=0.028), Psychosocial (F1,21=16.488, p=<0.001; F1,21=5.050, p=0.039), and Physical HRQoL (F1,21=21.671, p=<0.001; F1,21=5.119, p=0.038) at 7 and 30 days than players with minimal symptoms, and these differences resolved by 90 days. Conclusion As a groups, youth soccer players who sustained mTBI had transient impairments in HRQoL that resolved by 30 days. A subset of players with significant post-concussive symptoms at 7 days post-injury have poorer HRQoL for at least 30 days post-injury than those whose post-concussive symptoms had resolved within a week of injury. This suggests ongoing recovery in this subset at 30 days and potential utility of HRQoL as a measure of recovery.
PDF
