Calculation difficulties in children of very low birthweight: a neural correlate. (57/986)

Learning difficulties, including problems with numeracy, are common in Western populations. Many children with learning difficulty are survivors of preterm birth. Although some of these children have neurological disabilities, many are neurologically normal, and the latter group provides us with an important opportunity to investigate the neural bases of learning problems. We have conducted a neuroimaging study of adolescent children who had been born preterm at 30 weeks gestation or less, to investigate the relationship between brain structure and a specific difficulty in arithmetic calculation. Using voxel-based morphometry, we have been able to demonstrate that there is an area in the left parietal lobe where children without a deficit in calculation ability have more grey matter than those who do have this deficit. To our knowledge, this is the first report establishing a structural neural correlate of calculation ability in a group of neurologically normal individuals.  (+info)

Mild iodine deficiency is associated with elevated hearing thresholds in children in Benin. (58/986)

OBJECTIVE: Elevated hearing thresholds have been demonstrated in populations afflicted by endemic cretinism as a result of severe iodine deficiency. However, data on the effects of less severe iodine deficiency on hearing thresholds in apparently normal children are scant. This study addresses the question whether there is a relationship among iodine variables, hearing and mental performance in a mildly iodine-deficient population. DESIGN: A randomized, placebo-controlled intervention trial with an observation period of 11 months. SETTING: An iodine-deficient area in northern Benin. SUBJECTS: A total of 197 school children, aged 7-11 y. INTERVENTIONS: A total of 97 children received an oral dose of iodized oil, containing 540 mg I, while 100 children received a placebo. About 3-4 months after supplementation, the whole population began to have access to iodized salt. Non-verbal mental tests were administered and biochemical indicators (thyrotropin, free thyroxine, thyroglobulin and urinary iodine) were measured at the beginning and the end of the study. Hearing was measured at the end of the study in both ears by pure-tone audiometry at seven frequencies. RESULTS: In this mildly iodine-deficient child population children with higher serum thyroglobulin concentrations had significantly higher hearing thresholds in the higher frequency range (> or = 2000 Hz) than children with lower serum thyroglobulin concentration. Moreover children with lower hearing thresholds performed significantly better on the mental tests used. CONCLUSIONS: Even when iodine deficiency is 'mild', promotion of adequate iodine intake through salt iodization programs and other means remains crucial. SPONSORSHIP: Nestle Foundation, Lausanne, Switzerland; Wageningen University, Wageningen, The Netherlands.  (+info)

Neurodevelopmental outcomes in children after the fontan operation. (59/986)

BACKGROUND: Previous studies of patients after the Fontan operation have reported IQ scores lower than population norms. In the past decade, changes have occurred both in surgical methods used and in the patient population undergoing Fontan palliation. The present study examined the impact of these changes on neurodevelopmental outcomes after Fontan. METHODS AND RESULTS: Neuropsychological tests were administered to 27 five-year-old children after Fontan. Mean age at repair was 2 years 4 months. The present sample was compared with an earlier Fontan group (EFG) of 133 patients who underwent surgery in the 1970s and 1980s. Mean age at repair for the EFG was 7 years 3 months. Compared with EFG, the present study sample was younger at Fontan (P=0.0001) and more likely to have undergone a Norwood procedure (P=0.02), a pre-Fontan bidirectional cavopulmonary anastomosis (P<0.001), and Fontan fenestration (P=0.001). Although mean full-scale, verbal, and performance IQ scores were within 1 SD (15 points) of the population mean of 100 (93+/-16, 95+/-15, and 91+/-17, respectively), mean full-scale and performance IQ scores were significantly lower than this population mean (P=0.03 and P=0.01, respectively). CONCLUSIONS: Compared with a historical cohort of Fontan patients from this institution, a staged approach to Fontan earlier in life is not detrimental to neurodevelopmental outcome. Neurodevelopmental outcomes in children after Fontan are in the normal range, but performance remains lower than the general population.  (+info)

Stability and change in children's intelligence quotient scores: a comparison of two socioeconomically disparate communities. (60/986)

The authors estimated the influence of familial factors and community disadvantage on changes in children's intelligence quotient (IQ) scores from age 6 years to age 11 years. Data were obtained from a longitudinal study of the neuropsychiatric sequelae of low birth weight in two socioeconomically disparate, geographically defined communities in the Detroit, Michigan, metropolitan area. Representative samples of low birth weight and normal birth weight children from the City of Detroit (urban) and nearby middle-class suburbs (suburban) were assessed at age 6 years (in 1990-1992) and age 11 years (in 1995-1997) (n = 717). Children's IQs were measured using the Wechsler Intelligence Scale for Children-Revised. The familial factors considered included maternal IQ, education, and marital status. Multiple regression analysis applying generalized estimating equations was used. The IQs of urban children, regardless of birth weight, declined from age 6 years to age 11 years. The downward shift increased by 50% the proportion of urban children scoring 1 standard deviation below the standardized IQ mean of 100. A negligible change was observed in suburban children. Maternal IQ, education, and marital status and low birth weight predicted IQ at age 6 years but were unrelated to IQ change. Growing up in a racially segregated and disadvantaged community, more than individual and familial factors, may contribute to a decline in IQ score in the early school years.  (+info)

Early intervention promotes intellectual development of premature infants: a preliminary report. Early Intervention of Premature Infants Cooperative Research Group. (61/986)

OBJECTIVE: To evaluate the effect of early intervention on the intellectual development of the premature infants. METHODS: Premature infants at gestational age of 28-36.9 weeks were randomly divided into two groups: intervention and conventional care groups. Normal newborn infants during the same period were included in the control group (routine care). Up to March 1996, 156 cases were over the age 1.5-2 years (corrected age), 52 in the intervention group, 51 in the conventional care group and 53 in the normal control group. Parents were taught to carry out the 0-2 year intervention program, which included motor, cognitive, speech development and social behavior. Every three months, height, weight and head circumference were measured. At the age of one and a half and two years, all infants in the three groups received infant development tests of Child Development Center of China (CDCC) scale. The examiner did not know which infant had received intervention. RESULTS: There was no significant difference in biological factors among the two premature groups and in cultural and social factors among the three groups. Intelligence tests at the age of one and a half and two years showed that the average mental development index (MDI) in the intervention group was 13.8 and 14.6 higher than those in the conventional care group and the differences were significant. The psychomotor development index (PDI) was 5.2 and 4.7 higher but the differences were not significant. The MDI and PDI in the intervention group and normal control were quite close, but at two years, the MDI and PDI in the intervention group were 5.7 and 7.3 higher than those in the normal control and the differences were significant (P < 0.05). Compared with the normal control, the MDI in conventional care group at one and a half and two years of age were 11.5 and 8.9 lower. The difference was very significant. There were four cases of mental retardation, whose mental development index (MDI) was less then 70 in the conventional care group, but none in the intervention group. CONCLUSIONS: Early intervention can promote intellectual development of the premature infants and may be beneficial to the prevention of mental retardation. Early and intensive intervention can produce better results. Bringing parent's initiative into full play through deepening their understanding of the importance of early intervention is the key to success.  (+info)

Psychological eff-cts of halothane and isoflurane anesthesia. (62/986)

Psychological effects of halothane (16 subjects) and isoflurane (24 subjects) anesthesia on healthy young men were assessed prior to and 2,3,4,6,8, and 30 days after anesthesia. The results with each agent were compared with each other and with the results for 41 unanesthetized controls. Both agents altered psychological function. Changes in function were greatest 2 days after anesthesia; function had returned to near preanesthesia values 8 days after anesthesia. Only slight symptom and mood effects and no intellectual effect attributable to anesthesia remained 30 days after anesthesia. Halothane produced greater negative effects on moodds and symptoms and tended to produce greater negative effects on intellectural function than did isoflurane. The differences between the two anesthetics are consistent with differences in their solubilities and metabolism.  (+info)

Boy/girl differences in risk for reading disability: potential clues? (63/986)

The authors conducted a case-control study to determine whether risk factors for reading disability (RD) differentially affect boys and girls. The study population included all children born between 1976 and 1982 in Olmsted County, Minnesota (n = 5,701). A total of 303 RD cases were identified by using intelligence quotient and achievement test scores collected from school and medical records. After excluding those who met exclusion criteria (n = 869), controls consisted of all children not identified with RD (n = 4,529). The authors examined the association between RD and potential risk factors in boys and girls and confirmed their results in multivariable logistic regression models. Multivariable models indicated that girls of low birth weight were more than twice as likely to be identified as RD (odds ratio (OR) = 2.94, 95% confidence interval (CI): 1.09, 6.25). Girls whose mothers had 12 or fewer years of education were twice as likely to be identified as RD (OR = 2.14, 95% CI: 1.24, 3.72). However, girls whose fathers were aged 35 years or older at the time of birth were less likely to be identified as RD (OR = 0.24, 95% CI: 0.06, 0.92). Only 12 or fewer years of paternal education was associated with increased RD in boys (OR = 2.28, 95% CI: 1.59, 3.27). Boys and girls appear to be differentially susceptible to RD risk factors, suggesting that the biologic processes leading to RD may differ between boys and girls.  (+info)

The nuchocephalic reflex. (64/986)

The nuchocephalic reflex, previously undescribed, was investigated in a controlled study of 146 subjects ranging in age from 11 hours to 94 years. In 110 subjects over 16 years of age, the presence of the reflex was correlated directly with evidence of diffuse cerebral dysfunction as measured by a shortened form of the Wechsler Adult Intelligence Scale. Thirty-six children were studied from the newborn period to the age of 16 years. The reflex was found to be uninhibited in infants and to become inhibited by the age of 4 years. Among the adult subjects, the nuchocephalic reflex was found to be sensitive indicator of the status of higher cortical function. The presence or absence of the reflex appears to have somewhat different predictive value at different points in the adult age spectrum.  (+info)