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Background: Little research has been conducted on the mental health needs of adolescents with intellectual disability, despite the severity and rates of such needs being high throughout childhood and in adulthood. We have investigated the prevalence and predictors of mental health needs and service use in adolescents with intellectual disabilities. Materials and Methods: Service-based sample (n = 75) in one catchment area. Individual assessments were carried out. The main outcome was the presence of mental health needs measured by the Developmental Behaviour Checklist. Results: Prevalence of mental health needs increased from 51% as reported by parents to 67% as judged by clinical interviews. Caseness was associated with low adaptive functioning, diagnosis of autism and family history of mental illness. High scores on parent reports of participant mental ill-health showed negative correlations with adaptive functioning scores. Most individuals were in receipt of social and health care. Half of the participants had sought help for mental health needs. Almost half of those receiving medication were on psychiatric medication. Conclusions: Adolescents with intellectual disabilities may have considerable mental health problems which are functionally impairing yet frequently unidentified and hence untreated. Identification of those at risk and undertaking of a comprehensive needs assessment are essential to maximize potential and quality of life and to reduce further deficits and social exclusion.

Fragile X syndrome is the world's most common hereditary cause of intellectual disability in men and to a lesser extent in women. The disorder is caused by the silencing of a single gene on the X chromosome, the Fragile X Mental Retardation Gene-1. A substantial body of research across the disciplines of molecular genetics, child psychiatry and developmental neuroscience bears testament to a decade of exciting and innovative science that has advanced our knowledge about the fragile X "signature" or influence across cognitive and social development. The core aims of this review are to first discuss fragile X syndrome and premutation involvement in the context of current advances that demonstrate the dynamic nature of the genotype on phenotypic outcomes. Second, to discuss the implications of these recent advances for the development of clinical and educational interventions and resource tools that target specific phenotypic "signatures" within the fragile X continuum.

This is the first published case description in the current literature of the association of definite Gilles de la Tourette syndrome (GTS) and the Smith-Magenis syndrome (SMS), both confirmed by DSM-IV-TR criteria and molecular cytogenetic analysis, respectively. The co-occurrence of GTS, SMS and their common behavioural/neuropsychiatric abnormalities should warrant further genetic investigation of chromosome 17p11.2 deletion site as it may be a promising region for containing a gene(s) of aetiological importance in the development of the GTS phenotype. Alternatively, the co-occurrence may be due to the common endophenotypic mechanisms shared by these disorders, rather than being specific for GTS that could be explored using strategies of quantitative trait loci--endophenotype-based approach. Research into this genomic region may also benefit psychiatric genetic research in enhancing understanding of the biological and molecular underpinnings of common behavioural problems that are seen in both GTS and SMS. This would lead to advancement in neurobehavioural/neuropsychiatric genetics which will help in further explaining the broader perspective of gene-brain-behaviour interrelationships.

Background: Post-traumatic stress disorder (PTSD) is common and treatable. There is extensive research on people of average intelligence yet little on individuals with developmental disabilities. Methods: We report two people with intellectual disability (ID) who experienced PTSD. The relevance of their developmental difficulties, social and communication profiles, attentional skills, and causes of these, to their presentations is discussed. Results: Both individuals have fragile X syndrome and severe ID. One has Diagnostic and Statistical Manual - 4th Edition (DSM-IV) autistic disorder; the other DSM-IV attention deficit-hyperactivity disorder. They experienced developmental and psychological regressions, new challenging behaviours and exacerbations of existing ones coincident with emotional trauma. PTSD symptoms and phenomena were identifiable despite intellectual and communicatory impairments. Conclusion: Presentation of PTSD is influenced by degree and cause of ID, social circumstances, social and communicatory skills, nature and timing of traumatic experience and subsequent management. The paucity of literature suggests it is missed frequently in individuals with ID who risk having problems misattributed to other causes with potential for inappropriate interventions.

Fragile X syndrome is a neurodevelopmental disorder that is caused by large methylated expansions of a CGG repeat (>200) region upstream of the FMR1 gene that results in the lack of expression of the fragile X mental retardation protein (FMRP). Affected individuals display a neurobehavioral phenotype that includes a significant impairment in social cognition alongside deficits in attentional control, inhibition and working memory. In contrast, relatively little is known about the trajectory and specificity of any cognitive impairment associated with the fragile X premutation (''carrier-status'') (approximately 55-200 repeats). Here, we focus on one aspect of cognition that has been well documented in the fragile X full mutation, namely social cognition. The results suggest that premutation males display a pattern of deficit similar in profile, albeit milder in presentation, to that of the full mutation. However, little evidence emerged for a correlation between CGG repeat length and severity of phenotypic outcomes. The findings are discussed in the context of functional neuroimaging and brain-behaviour-molecular correlates. We speculate that the deficiencies in social cognition are attributable to impairment of neural pathways modulated by the cerebellum.

Background: Fragile X syndrome is one of the world's leading hereditary causes of developmental delay in males. The past decade has witnessed an explosion of research that has begun to unravel the condition at its various levels: from the genetic and brain levels to the cognitive level, and then to the environmental and behavioural levels. Our aim in this review is to attempt to integrate some of the extensive body of knowledge to move the research a step closer to understanding how the dynamics of atypical development can influence the specific cognitive and behavioural end-states frequently observed in children and adolescents with fragile X syndrome. Methods: We conducted a review of the current neuropsychological and neuropsychiatric approaches that have attempted to delineate the pattern of "spared" and "impaired" functions associated with the phenotype. Results: The profile of findings suggests that fragile X syndrome should not be viewed merely as a catalogue of spared and impaired cognitive functions or modules. Instead, there appears to be a process of almost gradual modularisation whereby cognitive mechanisms become domain specific as a function of development itself (Karmiloff-Smith, 1992). The results of a decade of intense research point towards an early weakness in one or more components of executive control rather than single, static higher-level deficits (e.g., spatial cognition, speech processing). This weakness affects both the development of more complex functions and current performance. Conclusions: The prevailing tendency to interpret developmental disorders in terms of fixed damage to distinct modular functions needs to be reconsidered. We offer this review as an example of an alternative approach, attempting to identify an initial deficit and its consequences for the course of development. Through better definition of the cognitive and behavioural phenotype, in combination with current progress in brain imaging techniques and molecular studies, the next decade should continue to hold exciting promise for fragile X syndrome and other neurodevelopmental disorders.

The clod method is a widely used and accurate bulk density method. However, its use is limited to sampling from soil pits. This study was conducted to: 1) determine whether clods collected from cores provide similar bulk density measurements to those collected from soil pits and 2) evaluate the impact of various clod bulk density methods on carbon stock calculation. Clods were collected from soil pits, 5.1 cm soil cores, and 8.9 cm soil cores. Three-dimensional laser scanning was used to measure the volume of the soil clods before and after oven-drying and bulk density was calculated as the dry mass of the clod divided by volume. Of 24 horizons sampled, 17 showed no significant effect of sampling method (core vs. pit) on dry bulk density. The error introduced by collecting clods from a core was small enough that it had no significant effect on carbon stock (p =.683). However, the moisture at which clods were scanned did have a significant effect on carbon stocks (p =.002 to 0.016). Data from the study suggest that collecting clods from soil cores introduces minimal error, but attention should be given to the moisture state at which clod volume is determined. [ABSTRACT FROM AUTHOR]