Greater brain response to emotional expressions of their own children in mothers of preterm infants: an fMRI study.

OBJECTIVE: The birth of a preterm infant and Neonatal Intensive Care Unit hospitalization constitute a potentially traumatic experience for mothers. Although behavioral studies investigated the parenting stress in preterm mothers, no study focused on the underlying neural mechanisms. We examined the effect of preterm births in mothers, by comparing brain activation in mothers of preterm and full-term infants. STUDY DESIGN: We used functional magnetic resonance imaging to measure the cerebral response of 10 first-time mothers of preterm infants (gestational age <32 weeks and/or birth weight <1500) and 11 mothers of full-term infants, viewing happy-, neutral- and distress-face images of their own infant, along with a matched unknown infant. RESULTS: While viewing own infant's face preterm mothers showed increased activation in emotional processing area (i.e., inferior frontal gyrus) and social cognition (i.e., supramarginal gyrus) and affiliative behavior (i.e., insula). CONCLUSION: Differential brain activation patterns in mothers appears to be a function of the atypical parenthood transition related to prematurity.

High quality surface reconstruction in radiotherapy: Cross-sectional contours to 3D mesh using wavelets.

A novel approach for three-dimensional (3D) surface reconstruction of anatomical structures in radiotherapy (RT) is presented. This is obtained from manual cross-sectional contours by combining both image voxel segmentation processing and implicit surface streaming methods using wavelets. 3D meshes reconstructed with the proposed approach are compared to those obtained from traditional triangulation algorithm. Qualitative and quantitative evaluations are performed in terms of mesh quality metrics. Differences in smoothness, detail and accuracy are observed in the comparison, considering three different anatomical districts and several organs at risk in radiotherapy. Overall best performances were recorded for the proposed approach, regardless the complexity of the anatomical structure. This demonstrates the efficacy of the proposed approach for the 3D surface reconstruction in radiotherapy and allows for further specific image analyses using real biomedical data.

Texture analysis to assess structural modifications induced by radiotherapy.

Texture analysis is an emerging tool employed in Radiotherapy (RT) to improve tumor characterization for planning and to evaluate treatment effects. In the treatment of Head and Neck Cancer, parotid glands can receive high dose that may compromise gland functionality and structure. Texture analysis was here applied on CT images of Head and Neck to evaluate changes in parotid gland structure during RT. CT images at the beginning, at the intermediate stage and at the end of RT were considered and in each time point different features (i.e. mean intensity, variance, entropy, homogeneity, local entropy, fractal dimension and volume) were extracted within parotid volume. A general decrease in tissue complexity and heterogeneity was found, with different time trend for textural features. This is explainable by different biological mechanisms associated to the variation of each index. Volume and mean intensity variation are also correlated with some pre-treatment dosimetric parameters, indicating a relationship between the dose plan and the structural variation estimated after RT.

Objective measures of perceptual quality for predicting speech intelligibility in sensorineural hearing loss.

An objective method to predict speech intelligibility in sensorineural hearing loss of different types and increasing degrees of severity is proposed and validated with experimental data. The novel approach is based on the combined use of acoustic simulations of impaired perception and objective measures of perceptual speech quality (PESQ). Acoustic simulations were obtained after degradation of the original, non distorted, speech waveforms by spectral smearing, expansive nonlinearity, and level scaling. PESQ was used to measure perceptual quality of the acoustic simulations obtained by varying the degree of the simulated hearing loss. A logistic function was applied to transform PESQ scores into predicted intelligibility scores. A set of CV and VC syllables in /a/, /u/, and /i/ contexts was used as reference test material. The method was validated with subjective measures of intelligibility of the degraded speech obtained in a group of 10 normal hearing subjects. Overall, prediction of experimental speech intelligibility through the transformed PESQ measures was good (R(2)=0.7; RMSE=0.08) revealing that the proposed approach could be a valuable aid in real clinical applications.

The effect of age and sex on facial mimicry: a three-dimensional study in healthy adults.

To assess sex- and age-related characteristics in standardized facial movements, 40 healthy adults (20 men, 20 women; aged 20-50 years) performed seven standardized facial movements (maximum smile; free smile; "surprise" with closed mouth; "surprise" with open mouth; eye closure; right- and left-side eye closures). The three-dimensional coordinates of 21 soft tissue facial landmarks were recorded by a motion analyser, their movements computed, and asymmetry indices calculated. Within each movement, total facial mobility was independent from sex and age (analysis of variance, p>0.05). Asymmetry indices of the eyes and mouth were similar in both sexes (p>0.05). Age significantly influenced eye and mouth asymmetries of the right-side eye closure, and eye asymmetry of the surprise movement. On average, the asymmetry indices of the symmetric movements were always lower than 8%, and most did not deviate from the expected value of 0 (Student's t). Larger asymmetries were found for the asymmetric eye closures (eyes, up to 50%, p<0.05; mouth, up to 30%, p<0.05 only in the 20-30-year-old subjects). In conclusion, sex and age had a limited influence on total facial motion and asymmetry in normal adult men and women.