Developmental white matter microstructure in autism phenotype and corresponding endophenotype during adolescence.

During adolescence, white matter microstructure undergoes an important stage of development. It is hypothesized that the alterations of brain connectivity that have a key role in autism spectrum conditions (ASCs) may interact with the development of white matter microstructure. This interaction may be present beyond the phenotype of autism in siblings of individuals with ASC, who are 10 to 20 times more likely to develop certain forms of ASC. We use diffusion tensor imaging to examine how white matter microstructure measurements correlate with age in typically developing individuals, and how this correlation differs in n=43 adolescents with ASC and their n=38 siblings. Correlations observed in n=40 typically developing individuals match developmental changes noted in previous longitudinal studies. In comparison, individuals with ASC display weaker negative correlation between age and mean diffusivity in a broad area centred in the right superior longitudinal fasciculus. These differences may be caused either by increased heterogeneity in ASC or by temporal alterations in the group's developmental pattern. Siblings of individuals with ASC also show diminished negative correlation between age and one component of mean diffusivity-second diffusion eigenvalue-in the right superior longitudinal fasciculus. As the observed differences match for location and correlation directionality in our comparison of typically developing individuals to those with ASC and their siblings, we propose that these alterations constitute a part of the endophenotype of autism.This research was funded by an MRC Clinician Scientist Fellowship to MDS from the UK Medical Research Council (G0701919). LRC was supported by the Gates Cambridge Scholarship Trust. SB-C was supported by the Wellcome Trust, the MRC and the Autism Research Trust, during the period of this work.This is the final published version. It first appeared at http://www.nature.com/tp/journal/v5/n3/full/tp201523a.html

Neuropsychological care and rehabilitation of cancer patients with chemobrain: strategies for evaluation and intervention development

Malignant tumors and their various treatments such as chemotherapy, radiotherapy and hormonal therapy can deleteriously affect a large number of cancer patients and survivors on multiple dimensions of psychosocial and neurocognitive functioning. Oncology researchers and clinicians are increasingly cognizant of the negative effects of cancer and its treatments on the brain and its mental processes and cognitive outcomes. Nevertheless, effective interventions to treat cancer and treatment-related neurocognitive dysfunction (CRND), also known as chemobrain, are still lacking. The paucity of data on effective treatments for CRND is due, at least partly, to difficulties understanding its etiology, and a lack of reliable methods for assessing its presence and severity. This paper provides an overview of the incidence, etiology, and magnitude of CRND, and discusses the plausible contributions of psychological, motor function, and linguistic and behavioral complications to CRND. Strategies for reliable neuropsychological screening and assessment, and development and testing of effective ways to mitigate CRND are also discussed