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Alcohol consumption during pregnancy causes Fetal Alcohol Spectrum Disorder (FASD), which includes a range of developmental deficits. Fetal alcohol syndrome (FAS) is the most severe form of FASD and can be diagnosed with pathognomonic facial features (smooth philtrum, short palpebral fissure, and thin upper vermilion). However, many children with developmental damage due to prenatal alcohol exposure exhibit no, or only a subset, of the above features, making diagnosis difficult. This study explored novel analyses to quantify the effect of a known dose of alcohol on specific facial measurements in sub-strains C57BL/B6J (B6J) and C57BL/6NHsd (B6N) mice. Mouse dams were provided alcohol (Alc) consisting of 4.8% (v/v) alcohol in a liquid diet for 16 days pre-pregnancy, chow and water diet during mating, and the alcohol liquid diet reinstated on gestational days 7(E7) to E17. Treatment controls included a pair-fed (PF) group given matched volumes of an alcohol-free liquid diet made isocalorically, and a group given ad lib access to lab chow and water (Chow). Maternal diet intake (Alc and PF), blood alcohol concentrations (BACs), embryo weights, and 15 morphometric facial measurements for E17 embryos were analyzed. B6N dams drank more alcohol during pregnancy and generated higher BAC than B6J dams. Both the Alc and PF treatments induced significant reductions in embryo weights relative to Chow in both sub-strains. Alcohol treatments produced significant changes, relative to controls, in four of the 15 facial measures for the B6N sub-strain, but only in two measures for the B6J sub-strain. Discriminant analysis demonstrated successful classification of the B6N alcohol-exposed versus non-alcohol exposed embryos with high sensitivity (86%), and specificity (80%), and overall classification (total correct 83%), while, B6J mice yielded sensitivity of 80%, specificity 78%, and overall correct classification in 79%. In addition, B6N mice showed significantly more effects of pair feeding on these facial measures than did B6J, suggesting that the B6N sub-strain may be more vulnerable to nutritional stress during pregnancy. Overall, these data indicate that B6N and B6J mice were both vulnerable to alcohol but show differences in the severity and location of alcohol-induced dysmorphic facial features and may parallel findings from human studies comparing different ethnic groups. Furthermore these findings suggest that discriminant analysis may be useful in predicting alcohol exposure in either mouse sub-strain.

Complex visual–motor behaviors dominate human–environment interactions. Letter production, writing individual letters by hand, is an example of a complex visual–motor behavior composed of numerous behavioral components, including the required motor movements and the percepts that those motor movements create. By manipulating and isolating components of letter production, we provide experimental evidence that this complex visual–motor behavior is supported by a widespread neural system that is composed of smaller subsystems related to different sensorimotor components. Adult participants hand-printed letters with and without “ink” on an MR-safe digital writing tablet, perceived static and dynamic representations of their own handwritten letters, and perceived typeface letters during fMRI scanning. Our results can be summarized by three main findings: (1) Frontoparietal systems were associated with the motor component of letter production, whereas temporo-parietal systems were more associated with the visual component. (2) The more anterior regions of the left intraparietal sulcus were more associated with the motor component, whereas the more posterior regions were more associated with the visual component, with an area of visual–motor overlap in the posterior intraparietal sulcus. (3) The left posterior intraparietal sulcus and right fusiform gyrus responded similarly to both visual and motor components, and both regions also responded more during the perception of one's own handwritten letters compared with perceiving typed letters. These findings suggest that the neural systems recruited during complex visual–motor behaviors are composed of a set of interrelated sensorimotor subsystems that support the full behavior in different ways and, furthermore, that some of these subsystems can be rerecruited during passive perception in the absence of the full visual–motor behavior.

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Background The identification of individuals exposed prenatally to alcohol can be challenging, with only those having the characteristic pattern of facial features, CNS abnormality, and growth retardation receiving a clinical diagnosis of fetal alcohol syndrome (FAS). Methods 17 anthropometric measurements were obtained at 5 and 9 years from 125 Cape Town, South African children, studied since birth. The children were divided into 3 groups: FAS or partial FAS (PFAS), heavily exposed nonsyndromal (HE), and non-alcohol exposed controls (C). Anthropometric measurements were evaluated for mean group differences. Logistic regression models were used to identify the subset of anthropometric measures that best predicted group membership. Anthropometric measurements were examined at the two ages in relation to prenatal alcohol exposure obtained prospectively from the mothers during pregnancy. Correlation of these facial measurements with key neurobehavioral outcomes including WISC-IV IQ and eyeblink conditioning was used to assess their utility as indicators of alcohol-related central nervous system impairment. Results Significant group differences were found for the majority of the anthropometric measures, with means of these measures smaller in the FAS/PFAS compared with HE or C. Upper facial widths, ear length, lower facial depth, and eye widths were consistent predictors distinguishing those exposed to alcohol from those who were not. Using longitudinal data, unique measures were identified that predicted facial anomalies at one age but not the other, suggesting the face changes as the individual matures. 41% of the FAS/PFAS group met criteria for microtia at both ages. Three of the predictive anthropometric measures were negatively related to measures of prenatal alcohol consumption, and all were positively related to at least one neurobehavioral outcome. Conclusions The analysis of longitudinal data identified a common set of predictors, as well as some that are unique at each age. Prenatal alcohol exposure appears to have its primary effect on brain growth, reflected by smaller forehead widths, and may suppress neural crest migration to the branchial arches, reflected by deficits in ear length and mandibular dimensions. These results may improve diagnostic resolution and enhance our understanding of the relation between the face and the neuropsychological deficits that occur.