Cortical responses to speech sounds in 3- and 6-month-old infants fed breast milk, milk formula, or soy formula.

Controversy exists about the safety of soy formula, with the main concern relating to potential estrogenic effects of soy protein. Since estrogens influence early brain development, we compared behavioral development and cortical responses (event-related potentials; ERPs) to speech sounds in infants fed either breast milk or formula (milk- or soy-based). Across-groups ERP measures were generally similar and behavioral measures were within normal ranges, suggesting no important influences of soy formula on behavioral development and brain function during the study period. Analyses relating ERP and behavioral measures revealed diet- and gender-specific emphases that may reflect differences in developmental trajectories of brain-behavior relationships.

Early infant diet and the omega 3 fatty acid DHA: effects on resting cardiovascular activity and behavioral development during the first half-year of life.

This investigation evaluated variations in resting heart rate (HR) measures during the first half year of life in healthy, full-term infants who were either breast-fed (BF), or fed formula with (milk-based: MF; soy-based: SF) or without (soy-based: SF(-)) commercially supplemented DHA (decosahexaenoic acid). In infants fed the DHA-deficient diet, higher HR and lower values for heart rate variability measures were observed, indicating decreased parasympathetic tone in this group. These effects, appearing at 4 months and continuing for the remainder of the study period, are consistent with suggestions that the 3-5-month postnatal interval may be an important period in the development of cardiovascular regulation. The absence of these effects in SF infants receiving the DHA-supplemented formula suggests that neither soy protein nor the associated phytochemicals in soy formula contribute to these effects to any appreciable extent. In general, the results do not indicate differences in any of the study variables attributable to soy formula per se.

The influence of infant diet on early developmental changes in processing human voice speech stimuli: ERP variations in breast and milk formula-fed infants at 3 and 6 months after birth.

The purpose of this investigation was to determine if processing of language stimuli during the first half year of life in breast-fed infants differs from that of formula-fed infants. This question was addressed by examining the brain event-related potentials of healthy infants receiving breast milk (n = 15) or milk-based formula (n = 18) recorded in response to consonant vowel syllables presented in an oddball paradigm. The same infants were studied when they were 3-months and 6-months-old. The two groups were comparable on several measures relating to biological and home environment variables previously reported to influence development, including gestation period, birth weight, mother's IQ, and family socioeconomic status, and did not differ in weight or mental or motor development at the times of the visits. In general, ERP response features previously documented in studies of syllable processing in 3-6-month-old infants were observed in this study, including positive components at asymptotically equal to 190 msec (P1), asymptotically equal to 370 msec (P2), and asymptotically equal to 600 msec (P600), and negative components at asymptotically equal to 250 msec (N250), asymptotically equal to 450 msec (N450), and a late, negative going slow wave between 655 and 995 msec (LSW). For both groups there were instances where specific components were either poorly defined, e.g., P1 and N250 to the infrequent syllable at 3 months, N450 and P600 to this syllable at both ages, or not present in many infants, e.g., the P600 to the frequent syllable at 6 months. These variations appeared to be related to individual differences in development or paradigm-related features, i.e., ISI and frequency of syllable occurrence.

Effects of breast milk and milk formula diets on synthesized speech sound-induced event-related potentials in 3- and 6-month-old infants.

Effects of breast milk and milk formula supplemented with docosahexaenoic acid and arachidonic acid on speech processing were investigated by recording event-related potentials (ERPs) to synthesized /pa/ and /ba/ (oddball paradigm, 80%:20%) at 3 and 6 months of age. Behavioral assessment was also obtained. A major positive component (P200) was elicited by both types of sounds. It had a maximal scalp distribution in the fronto-central areas in both groups of infants. The mean latencies did not differ between the groups or between the stimulus types. However, the latencies decreased across age in both groups. The mean P200 amplitude in the formula-fed infants was lower than that in the breast-fed infants, but the difference was not significant. The between-stimulus differences in frontal P200 amplitudes were positively correlated with the behavioral scores of Bayley Index of Infant Development. These data suggest that the processing of the present speech stimuli is not affected by the investigated diets in the early infancy.

Growth status related to brain responses, nutrition, home environment, and behavior in infants and toddlers.

To investigate whether growth status in infants and toddlers affects processes involved in speech perception and discrimination, cortical event-related potentials (ERPs) to consonant-vowel syllables were recorded from 48 healthy babies: 26 low in growth status (LGS, < 25 th percentile in growth measures) and from 22 normal in growth status (NGS, 25t--75 th percentile in growth measures). Food records indicated no significant differences in the amounts of various nutrients consumed in the two groups, but LGS babies consumed slightly more of most nutrients than NGS babies. In response to speech stimuli (either /pa/ or /ba/ presented with 20 and 80% randomized occurrence), brain ERPs showed two prominent post-stimulus components: a large positive wave peaking at about 484 msec and a negative but positive going slow wave (SW) between 867 and 1199 msec. Principal components analysis followed by promax rotation revealed four additional important components. Maximum peak and latency values-for these components showed that NGS and LGS babies differed from one another on all measures in either amplitude, latency, or both. Comparing the two groups of babies, only the LGS group demonstrated a deficit in the phonetic discrimination of speech sounds. The growth deficiencies of the LGS group could not be attributed to the lack of an adequate diet. These negative findings are present in babies generally considered to be healthy (lowest 10-25% in growth measures). This underscores the need for research examining in more detail the relationship between growth status and cognitive growth.

A new scaling method for topographical comparisons of event-related potentials.

Recent studies have demonstrated that comparisons of scalp topographical distributions of event-related potentials (ERPs) between experiment conditions may not correctly indicate underlying changes in neural sources if the signals are not scaled prior to the comparisons. This important issue was re-evaluated in this paper using both simulated and experimental data. Simulated data were generated according to 16 different brain models containing 2-4 dipole sources varying in strength, orientation, origin and number. The changes made in the strength, orientation and origin included relative changes between the sources or symmetrical changes in the sources. Experimental data were ERPs collected from 45 infants at 3 months of age. Influences of linked-ear and average references were examined. A scaling method based on relations of signal amplitudes between conditions was devised and compared with the vector method (McCarthy and Wood, 1985). While real topographic differences generated by complex changes in underlying sources were preserved, interactions between condition and electrode site due to mere strength changes were successfully identified by the new method, irrespective of reference method used. However, the vector method was not always reliable because failure to differentiate or mistakenly indicate changes in sources may occur when a linked-mastoid reference was used. The method presented in this paper is reliable and recommended prior to topographic comparisons to distinguish different types of changes in underlying neural sources.

Effects of a carbohydrate supplement upon resting brain activity.

Glucose is a major energy source for the brain, and along with several monosaccharide derivatives as components of brain gangliosides, they play important roles in neurologic function. However, there is little information available on the role of glucose and other monosaccharides on resting brain activity. This study was designed to evaluate the effects of a single dose of a carbohydrate supplement containing glucose and several of its derivatives on resting brain activity in 20 healthy male college students. The supplement provided an insignificant amount of carbohydrate (3.9 g), protein (0.28 g), fat (0 g), and calories (14 kcal). The amount of glucose in the supplement was 0.5 g (1% the amount of glucose used in adult studies of cognitive functioning and memory). We hypothesized that the glyconutrient supplement would enhance brain activity associated with alertness and attention. The study design was double blind, with subjects randomly assigned to one of two orders, either carbohydrate supplement week one followed by placebo a week later, or the opposite. Electrical brain activity was monitored by 15 electrodes positioned at nine standard international 10-20 system locations, including three bilateral pairs at frontal, parietal, and occipital sites. Thirty minutes following ingestion of a placebo or carbohydrate supplement drink, EEG activity was recorded for 10-mins while subjects focused on a stationary visual target. Spectral power of resting brain activity was computed and analyzed contrasting the placebo and supplement groups. Relative to placebo, the carbohydrate supplement significantly enhanced power in three brain wave frequencies (theta, alpha, and beta) that are known to be associated with attention and arousal. Since changes were observed in the supplement but not placebo group, our study suggests that additional sugars in the glyconutritional supplement facilitate enhancement of brain electrical activity. Whether the apparent enhancement of arousal in baseline recordings is associated with improved task performance remains to be determined.

Parental perception and factors associated with glycemic control in pediatric patients with type 1 diabetes.

OBJECTIVE: To compare subjective parental perceptions of short-term diabetes control with objective glycated hemoglobin (HbA1c) measurements in a pediatric population. METHODS: Parents of 159 children and adolescents with type 1 diabetes anonymously completed a questionnaire concerning demographics, parental perception of the child's recent glycemic control, concern about nocturnal blood glucose levels, and factors related to severity of the child's diabetes. Nonparametric correlations were performed among all variables and the child's current HbA1c measurement. Good short-term glycemic control was defined as an HbA1c value of < or = 8.5%. RESULTS: Five factors were found to correlate significantly with good glycemic control, and these variables were subjected to a logistic regression analysis. With use of a cutoff value of 0.58, results explained 26% of the variance and had an overall 71% correct classification rate. Children with good glycemic control were younger, had a shorter duration of diabetes, lived in families with higher socioeconomic status, were less likely to experience hospitalizations due to their diabetes, and had parents who "always worried" about nocturnal blood glucose variations. Parental perception and HbA1c values were not significantly related (P>0.19); 60% of the parents correctly perceived the status of diabetes in their children, and 40% misperceived the level of glycemic control. Further analysis suggested that accuracy of parental perception was highly dependent on the child's level of glycemic control. Parents whose children had lower HbA1c values (< or = 7.5%) correctly perceived the status of blood glucose control in their children, whereas parents whose children had poorer glycemic control (HbA1c > or = 9.5%) had inaccurate perceptions. CONCLUSION: Subjective parental perceptions of diabetes control in their children may not correspond to objective assessments. Our findings suggest a need for more educational feedback concerning HbA1c levels and recommended goals for glycemic control.

Teenage status of hyperactive and nonhyperactive learning disabled boys.

Three groups of learning disabled boys--hyperactives, normoactives, and hypoactives--were studied in grade school, reevaluated at fourteen. At follow-up, all three groups remained at disadvantage to controls on academic and cognitive measures and on complex reaction time. Half the hyperactives had experienced major conflicts with authority, and over a third of hypoactives exhibited psychologically disturbing behaviors. Mental health of normoactives appeared comparable to controls.