A CONTEXTUAL APPROACH TO UNDERSTANDING PSYCHIATRIC COMORBIDITIES IN ADOLESCENTS WITH AUTISM SPECTRUM DISORDER: INDIVIDUAL, PEER, AND FAMILY FACTORS

Psychiatric comorbidities are common in youth with Autism Spectrum Disorders (ASD) and can have a negative impact on adaptive functioning and quality of life. Research has primarily focused on individual characteristics associated with internalizing problems such as age, intelligence, and social functioning. However, developmental theory supports the notion that individual level factors are necessary but not sufficient to understand the mental health of youth with ASD. Using the Family Ecology Framework as a guide, the purpose of this study was to examine how peer and family contexts are associated with anxiety and depression symptoms of adolescents with ASD. Using data from adolescents with ASD (13-17 years old) and their primary caregivers (N = 166), this study tested a conditional process model in which youths’ social-communication skills were associated with their mental health symptoms indirectly via experiences of peer victimization, with family competence acting as a buffer against the negative impact of peer victimization on anxiety and depression symptoms. Results suggest that the peer context is important when considering the mental health of adolescents with ASD. Specifically, deficits in social-communication skills were associated with higher levels of parent-reported anxiety and depression symptoms through increased adolescent-reports of peer victimization; however, the hypothesized buffering effect of family competence was not statistically significant. Findings from this study suggest the benefits of utilizing developmentally sensitive, contextual approaches when examining psychiatric comorbidities in adolescents with ASD

The Family Affective Attitude Rating Scale in Children with Asthma: The Association between Relational Schemas and Emotional Security

The Five Minute Speech sample is a cost effective, efficient means of data collection in developmental research, but recent criticism of traditional coding methods associated with the methodology has spurred the creation of more developmentally appropriate coding systems. The purpose of this study is to examine the reliability and validity of a new coding system, The Family Affective Attitudes Rating Scale (FAARS), for use in children with chronic illness. Results did not support the use of this coding system, at least in its current form, in a pediatric asthma population. Discussion focuses on whether the FAARS may be of use when examined on an item level and directions for future research - such as profile analyses and edits to the coding system - that may better capture the experiences of parenting a child with chronic illness

Aging and central vision loss: Relationship between the cortical macro-structure and micro-structure

Aging and central vision loss are associated with cortical atrophies, but little is known about the relationship between cortical thinning and the underlying cellular structure. We compared the macro- and micro-structure of the cortical gray and superficial white matter of 38 patients with juvenile (JMD) or age-related (AMD) macular degeneration and 38 healthy humans (19-84 years) by multimodal MRI including diffusion-tensor imaging (DTI). A factor analysis showed that cortical thickness, tissue-dependent measures, and DTI-based measures were sensitive to distinct components of brain structure. Age-related cortical thinning and increased diffusion were observed across most of the cortex, but increased T1-weighted intensities (frontal), reduced T2-weighted intensities (occipital), and reduced anisotropy (medial) were limited to confined cortical regions. Vision loss was associated with cortical thinning and enhanced diffusion in the gray matter (less in the white matter) of the occipital central visual field representation. Moreover, AMD (but not JMD) patients showed enhanced diffusion in lateral occipito-temporal cortex and cortical thinning in the posterior cingulum. These findings demonstrate that changes in brain structure are best quantified by multimodal imaging. They further suggest that age-related brain atrophies (cortical thinning) reflect diverse micro-structural etiologies. Moreover, juvenile and age-related macular degeneration are associated with distinct patterns of micro-structural alterations

Estimating Receptive Field Size from fMRI Data in Human Striate and Extrastriate Visual Cortex

Functional magnetic resonance imaging (fMRI) was used to estimate the average receptive field sizes of neurons in each of several striate and extrastriate visual areas of the human cerebral cortex. The boundaries of the visual areas were determined by retinotopic mapping procedures and were visualized on flattened representations of the occipital cortex. Estimates of receptive field size were derived from the temporal duration of the functional activation at each cortical location as a visual stimulus passed through the receptive fields represented at that location. Receptive fields are smallest in the primary visual cortex (V1). They are larger in V2, larger again in V3/VP and largest of all in areas V3A and V4. In all these areas, receptive fields increase in size with increasing stimulus eccentricity. The results are qualitatively in line with those obtained by others in macaque monkeys using neurophysiological methods

Visual contrast response functions in Parkinson's disease: evidence from electroretinograms, visually evoked potentials and psychophysics

Objectives: Visual contrast detection thresholds and suprathreshold contrast discrimination thresholds were compared to luminance and flash/pattern electroretinograms (ERG) and visually evoked potentials (VEP) in patients with Parkinson's disease (n=31), patients with multiple system atrophy (n=6), patients with progressive supranuclear palsy (n=6) and control patients without central nervous disease (n=33). Methods: The stimuli were luminance modulated full-field (flash) or horizontally oriented sinewave gratings (pattern), the latter having either a low (0.5 cycles/deg) or medium (4.0 cycles/deg) spatial frequency. Stimulus contrast ranged from 10 to 80% so that contrast response functions could be derived. Results: Contrast thresholds were higher in the patients with Parkinson's disease than in the control patients. Contrast discrimination thresholds were also somewhat elevated in patients with Parkinson's disease. Pattern ERG amplitudes were significantly reduced in patients with Parkinson's disease for the medium spatial frequency stimulus, but less for the low spatial frequency and flash stimuli. Conclusions: Our results suggest that Parkinson’s disease impairs contrast processing in the retina. VEP amplitudes did not significantly differ between the groups for the conditions tested. Patients with progressive supranuclear palsy also showed impaired contrast perception and reduced ERG amplitudes, whereas patients with multiple system atrophy were less impaired