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Visual experiences increase our ability to discriminate environmentally relevant stimuli (native stimuli, e.g., human faces) at the cost of a reduced sensitivity to irrelevant or infrequent stimuli (non-native stimuli, e.g., monkey/ape faces)-a developmental progression known as perceptual narrowing. One possible source of the reduced sensitivity in distinguishing non-native stimuli (e.g., one ape face vs. another ape face) could be underspecified attentional search templates (i.e., working memory representations). To determine whether perceptual narrowing stems from underspecified attentional templates for non-native exemplars, this study used ERP (N2pc component) and behavioral measures in a visual search task, where the target was either an exemplar (e.g., a specific ape face) or a category (e.g., any ape face). The N2pc component, an ERP marker of early attentional selection emerging at 200 msec prior to behavior, is typically modulated by the specificity of the target and, therefore, attentional template-it is larger for specific items versus categories. In two experiments using both human and ape faces (i.e., native and non-native stimuli), we found that perceptual narrowing affects later response selection (i.e., manual RT and accuracy), but not early attentional selection relying on attentional templates (i.e., the N2pc component). Our ERP results show that adults deploy exemplar level attentional templates for non-native stimuli (as well as native stimuli), despite poor downstream behavioral performance. Our findings suggest that long-term previous experience with reduced exemplar level judgments (i.e., perceptual narrowing) does not appear to eliminate early attentional selection of non-native exemplars.

Systematic investigation of individuals with intellectual disability after genetic diagnosis can illuminate specific phenotypes and mechanisms relevant to common neurodevelopmental disorders. We report the neurological, cognitive and neuroanatomical characteristics of nine males from three families with loss-of-function mutations in ZDHHC9 (OMIM #300799). All known cases of X-linked intellectual disability (XLID) due to ZDHHC9 mutation in the United Kingdom were invited to participate in a study of neurocognitive and neuroimaging phenotypes. Seven out of nine males with ZDHHC9 mutations had been diagnosed with epilepsy, exceeding epilepsy risk in XLID comparison subjects (P = 0.01). Seizure histories and EEG features amongst ZDHHC9 mutation cases shared characteristics with rolandic epilepsy (RE). Specific cognitive deficits differentiated males with ZDHHC9 mutations from XLID comparison subjects and converged with reported linguistic and nonlinguistic deficits in idiopathic RE: impaired oromotor control, reduced verbal fluency, and impaired inhibitory control on visual attention tasks. Consistent neuroanatomical abnormalities included thalamic and striatal volume reductions and hypoplasia of the corpus callosum. Mutations in ZDHHC9 are associated with susceptibility to focal seizures and specific cognitive impairments intersecting with the RE spectrum. Neurocognitive deficits are accompanied by consistent abnormalities of subcortical structures and inter-hemispheric connectivity. The biochemical, cellular and network-level mechanisms responsible for the ZDHHC9-associated neurocognitive phenotype may be relevant to cognitive outcomes in RE.

What cognitive processes influence how well we maintain information in visual short-term memory (VSTM)? We used a developmentally informed design to delve into the interplay of top-down spatial biases with the nature of the internal memory codes, motivated by documented changes for both factors over childhood. Seven-year-olds, 11-year-olds, and adults completed a VSTM task in which they decided whether a probe item had been present in a preceding memory array. Spatial cues guided participants' attention to the likely location of the to-be-probed item during maintenance. We manipulated the memoranda to contain either highly familiar items or unfamiliar abstract shapes. All participants benefited from cues during maintenance, although benefits were smaller for 7-year-olds than for older participants. Critically, attentional benefits interacted with the nature of the memoranda: Better VSTM maintenance was obtained for cued familiar items. Furthermore, attentional benefits for famil...

Rare pathogenic variants in membrane-associated guanylate kinase (MAGUK) genes cause intellectual disability (ID) and have recently been associated with neuropsychiatric risk in the non-ID population. However, it is not known whether risk for psychiatric symptoms amongst individuals with ID due to MAGUK gene mutations is higher than expected for the degree of general intellectual impairment, nor whether specific cognitive differences are associated with disruption to this gene functional network. This study addresses these two questions via behavioural questionnaires and cognitive testing, applying quantitative methods previously validated in populations with ID. We compared males with X-linked ID caused by mutations in three MAGUK genes (PAK3, DLG3, OPHN1; n = 9) to males with ID caused by mutations in other X chromosome genes (n = 17). Non-parametric and parametric analyses were applied as appropriate to data. Groups did not differ in age, global cognitive impairment, adaptive fun...

Social anxiety disorder represents a debilitating condition that has large adverse effects on the quality of social connections, educational achievement and wellbeing. Age-of-onset data suggests that early adolescence is a developmentally sensitive juncture for the onset of social anxiety. In this review, we highlight the potential of using a developmental cognitive neuroscience approach to understand (i) why there are normative increases in social worries in adolescence and (ii) how adolescence-associated changes may 'bring out' neuro-cognitive risk factors for social anxiety in a subset of individuals during this developmental period. We also speculate on how changes that occur in learning and plasticity may allow for optimal acquisition of more adaptive neurocognitive strategies through external interventions. Hence, for the minority of individuals who require external interventions to target their social fears, this enhanced flexibility could result in more powerful and ...

Through the increased availability and sophistication of genetic testing, it is now possible to identify causal diagnoses in a growing proportion of children with neurodevelopmental disorders. In addition to developmental delay and intellectual disability, many genetic disorders are associated with high risks of psychopathology, which curtail the wellbeing of affected individuals and their families. Beyond the identification of significant clinical needs, understanding the diverse pathways from rare genetic mutations to cognitive dysfunction and emotional-behavioural disturbance has theoretical and practical utility. We overview (based on a strategic search of the literature) the state-of-the-art on causal mechanisms leading to one of the most common childhood behavioural diagnoses - attention deficit hyperactivity disorder (ADHD) - in the context of specific genetic disorders. We focus on new insights emerging from the mapping of causal pathways from identified genetic differences to neuronal biology, brain abnormalities, cognitive processing differences and ultimately behavioural symptoms of ADHD. First, ADHD research in the context of rare genotypes highlights the complexity of multilevel mechanisms contributing to psychopathology risk. Second, comparisons between genetic disorders associated with similar psychopathology risks can elucidate convergent or distinct mechanisms at each level of analysis, which may inform therapeutic interventions and prognosis. Third, genetic disorders provide an unparalleled opportunity to observe dynamic developmental interactions between neurocognitive risk and behavioural symptoms. Fourth, variation in expression of psychopathology risk within each genetic disorder points to putative moderating and protective factors within the genome and the environment. A common imperative emerging within psychopathology research is the need to investigate mechanistically how developmental trajectories converge or diverge between and within genotype-defined groups. Crucially, as genetic predispositions modify interaction dynamics from the outset, longitudinal research is required to understand the multi-level developmental processes that mediate symptom evolution.

The world is cluttered with more information than can be processed at once. Attention is defined as a process or computation that is applied to competing environmental information, the result of which is to bias selection and action to one option while simul‑ taneously filtering interference from the remaining alternatives 1–4. Framing attention as a computation is useful because it explains how attention processes can be carried out on a range of sensory inputs, as well as on more‑abstract representations. For exam‑ ple, visual attention can bias selection of information about objects, such as particular features or locations. Attention can also act to select goals for action from the contents of working memory. In all these cases, attention processes determine what information is selected for subsequent perception, action, learning and memory, imposing a crucial processing bottleneck. It is there‑ fore one of the most‑studied mechanisms in the adult cognitive neurosciences. However, a complete understanding of attention processes must also include an understanding of their developmental origins. In this Review, we highlight how studying developing rather than developed attentional states broadens our understanding of attention mecha‑ nisms and forces a shift in focus from considering atten‑ tion as an isolated process towards an understanding of its links with perception and memory, as well as its genetic constraints and malleability. We discuss studies of typical development of attention processes and stud‑ ies of neurodevelopmental disorders in which attention processes are atypical. It is important to note that atten‑ tion operates in various sensory modalities. Here, we focus largely on cortical mechanisms of visual atten‑ tion development, but we suggest that the processes and approaches discussed here may operate in a similar way across other sensory modalities. Finally, we propose novel ideas for successful training of attention during development.

Our ability to maintain visuo-spatial information increases gradually through childhood and is highly variable across individuals, although the cognitive and neural mechanisms underpinning these differences in capacity are unknown. We presented participants with arrays of to-be-remembered items containing two targets, four targets, or two targets and two distracters. The participants were divided into three groups: (i) high-capacity adults; (ii) low-capacity adults; and (iii) typically developing children. In addition to our behavioral methods we used electrophysiological scalp recordings to contrast the immature VSTM capacity of the children with the deficient VSTM capacity of the low-capacity adults. We also observed a relative negativity in the maintenance delay, over scalp contralateral to the original locations of the memoranda. For the low-capacity adults, this negativity was similarly modulated by target and distracter items, indicative of poor selectivity. This was not the case for the high-capacity adults; the response to memory arrays containing two target items and two distracters was equivalent to the response elicited by arrays containing only two target items. Importantly, the pattern of results in the children's ERP data was equivalent to that of the high-capacity adults, rather than to the performance-matched low-capacity adults. In short, despite their obvious differences in capacity, children are not specifically impaired at filtering out distractors, as characteristic of low-capacity adults. © 2013 Wiley Periodicals, Inc. Dev PsychobiolOur ability to maintain visuo-spatial information increases gradually through childhood and is highly variable across individuals, although the cognitive and neural mechanisms underpinning these differences in capacity are unknown. We presented participants with arrays of to-be-remembered items containing two targets, four targets, or two targets and two distracters. The participants were divided into three groups: (i) high-capacity adults; (ii) low-capacity adults; and (iii) typically developing children. In addition to our behavioral methods we used electrophysiological scalp recordings to contrast the immature VSTM capacity of the children with the deficient VSTM capacity of the low-capacity adults. We also observed a relative negativity in the maintenance delay, over scalp contralateral to the original locations of the memoranda. For the low-capacity adults, this negativity was similarly modulated by target and distracter items, indicative of poor selectivity. This was not the case for the high-capacity adults; the response to memory arrays containing two target items and two distracters was equivalent to the response elicited by arrays containing only two target items. Importantly, the pattern of results in the children's ERP data was equivalent to that of the high-capacity adults, rather than to the performance-matched low-capacity adults. In short, despite their obvious differences in capacity, children are not specifically impaired at filtering out distractors, as characteristic of low-capacity adults. © 2013 Wiley Periodicals, Inc. Dev Psychobiol

Fragile X syndrome (FXS) is due to the silencing of a single X-linked gene and it is associated with striking attentional difficulties. As FXS is well characterised at the cellular level, the condition provides a unique opportunity to investigate how a genetic dysfunction can impact on the development of neurocomputational properties relevant to attention. Thirteen young boys with FXS and 13 mental-age-matched typically developing controls performed a touch-screen-based search task that manipulated the similarity between targets and distractors and their heterogeneity in size. Search speed, path and errors were recorded as multiple measures of performance. Children did not differ in overall search speed or path when searching amongst distractors, but striking error patterns distinguished children with FXS from controls. Firstly, although clear markers of previously found targets remained on screen, children with FXS perseverated on touching previous hits more than typically developing controls, consistent with the well-documented inhibitory deficits in adults with the disorder. Secondly, they could accurately discriminate single target-distractor pairs, but, when searching a complex display, they touched distractors more often than control children when distractors were similar to targets and especially so when these were infrequent, highlighting difficulties in judging relative size and allocate attentional weight independently of stimulus frequency. Thirdly, their performance was also characterised by inaccuracies in pointing, suggesting additional motor control deficits. Taken together, the findings suggest that fragile X syndrome affects the early development of multiple processes contributing to efficient attentional selection, as would be predicted from an understanding of the neurocomputational changes associated with the disorder.

AimTo review systematically the neurodevelopmental characteristics of individuals with sex chromosome trisomies (SCTs).MethodA bibliographic search identified English-language articles on SCTs. The focus was on studies unbiased by clinical referral, with power of at least 0.69 to detect an effect size of 1.0.ResultsWe identified 35 articles on five neonatally identified samples that had adequate power for our review. An additional 11 studies were included where cases had been identified for reasons other than neurodevelopmental concerns. Individuals with an additional X chromosome had mean IQs that were within broadly normal limits but lower than the respective comparison groups, with verbal IQ most affected. Cognitive outcomes were poorest for females with XXX. Males with XYY had normal-range IQs, but all three SCT groups (XXX, XXY, and XYY) had marked difficulties in speech and language, motor skills, and educational achievement. Nevertheless, most adults with SCTs lived independently. Less evidence was available for brain structure and for attention, social, and psychiatric outcomes. Within each group there was much variation.InterpretationIndividuals with SCTs are at risk of cognitive and behavioural difficulties. However, the evidence base is slender, and further research is needed to ascertain the nature, severity, and causes of these difficulties in unselected samples.