Although the dominant approach posits that developmental dyslexia arises from deficits in systems that are exclusively linguistic in nature (i.e., phonological deficit theory), dyslexics show a variety of lower level deficits in sensory and attentional processing. Although their link to the reading disorder remains contentious, recent empirical and computational studies suggest that spatial attention plays an important role in phonological decoding. The present behavioral study investigated exogenous spatial attention in dyslexic children and matched controls by measuring RTs to visual and auditory stimuli in cued-detection tasks. Dyslexics with poor nonword decoding accuracy showed a slower time course of visual and auditory (multisensory) spatial attention compared with both chronological age and reading level controls as well as compared with dyslexics with slow but accurate nonword decoding. Individual differences in the time course of multisensory spatial attention accounted for 31% of unique variance in the nonword reading performance of the entire dyslexic sample after controlling for age, IQ, and phonological skills. The present study suggests that multisensory "sluggish attention shifting"-related to a temporoparietal dysfunction-selectively impairs the sublexical mechanisms that are critical for reading development. These findings may offer a new approach for early identification and remediation of developmental dyslexia.

IntroductIonThe increasing prevalence of obesity during the last decades (1) is ascribed mainly to a mismatch between energy intake and energy expenditure (EE) (2,3). The factors that influence this balance are numerous and complex, involving genes, environment, and their interaction. However, the rationale of weight management strategies is to identify and modify the amount of energy introduced and expended in order to regain normal body weight (BW) (1). EE is a major determinant of energy balance and body composition. According to an usually accepted scheme in human nutrition, daily EE (DEE) can be partitioned between basal metabolic rate (BMR) extrapolated to 24 h, which corresponds to the energy needed to sustain the body functions at rest and which accounts for ~65% of DEE in sedentary subjects (4); EE associated with physical activity (often referred to as the thermic effect of activity), which accounts for ~25% of DEE (5); and the thermic effect of food, which includes EE due to digestion, absorption, and metabolism of nutrients and which accounts for ~10% of DEE (5). Because of its large contribution to DEE, especially in obese subjects, BMR has frequently been the main focus of attention in the studies on the development and treatment of obesity.BMR can be considered as the sum of the EEs of tissues and organs in a fasting and resting state and in thermoneutral conditions. It depends on the mass and metabolic rate of tissues and organs (6). For instance, EE is ~10, 15, 20, 35, and 35 times higher in the digestive tract, liver, brain, heart, and kidney than in resting muscle, whereas it is only ~1/3 of resting muscle in white adipose tissues (7). Thus, although organs only account for ~7% of BW, they contribute ~60% of BMR. In comparison, skeletal and adipose tissues account for 35-40% of BW but only 18-22% and 3-4% of BMR, respectively (8). Generally, BMR depends on body composition as expressed by fat-free mass (FFM) and fat mass (FM) and on gender, age, physical activity, and nutritional status. The main determinant of BMR is FFM (6), whereas FM is significant only in obese subjects (9). Gender is also a significant determinant of BMR, with men having a greater BMR than females after adjustment for body composition (9,10). In addition, BMR markedly decreases with advancing age in sedentary populations (11) The objective of the present study was to explore the relationship between basal metabolic rate (BMR), gender, age, anthropometric characteristics, and body composition in severely obese white subjects. In total, 1,412 obese white children and adolescents (BMI > 97° percentile for gender and age) and 7,368 obese adults (BMI > 30 kg/m 2 ) from 7 to 74 years were enrolled in this study. BMR was measured using an indirect calorimeter equipped with a canopy and fat-free mass (FFM) were obtained using tetrapolar bioelectrical impedance analysis (BIA). Using analysis of covariance, we tested the effect of gender on the relationship between BMR, age, anthropometry, and body composition. In children and ad...

Physical activity is essential in obesity management, but exercise capacity is compromised in obese individuals due to the excessive body mass, impacting on body movement's energetics, and to the dysfunctions of regulatory mechanisms, affecting cardiovascular responses. This study aims to compare the energetics and cardiovascular responses of walking and cycling in obese women, and to formulate recommendations regarding the most suitable type of exercise for obesity. Fifteen obese (OB) and six normal weight (NW) women exercised on treadmill (TM) and cycle ergometer (CE). During both exercise modalities, metabolic rate was higher in OB than in NW and correlated with measures of body mass. Leg movement metabolic rate during cycling depended upon individual adiposity, and when accounted for, mechanical efficiency was similar in the two groups. When accounting for extra mass, differences in metabolic rate among groups are abolished for CE, indicating no obesity impairment of muscle efficiency, but not for TM, suggesting that differences in biomechanics may explain the higher net cost of transport of OB. In both groups, HR was higher during CE than TM at the same oxygen uptake (VO(2)), but in OB the HR increment over VO(2) was greater for CE than for TM. Therefore, due to different cardiovascular responses to TM and CE in OB, walking is more convenient, enabling OB to attain target energy expenditure at lower HR or in a shorter time.