Renee C. Wachtel

Clinical linguistic and auditory milestone scale: prediction of cognition in infancy.

At each well‐child examination between birth and two years, parents of 448 infants were questioned about their childs age at attainment of 25 linguistic and auditory milestones. Parental reports were compared with the results of independently administered Bayley Mental Developmental Index (MDI) at one year of age. Parental recall of information was high, ranging from 70 to 99 per cent for 21 of the 25 milestones. The milestone performance of infants with normal MDI scores showed an orderly, sequential progression of expressive and receptive language. Across the entire population studied, the correlation between milestone attainment and MDI was statistically significant for 24 of the 25 milestones, and later attainment of milestones correlated with lower MDI. As a group, ‘delayed’ infants (MDI <68) attained milestones significantly later than ‘average’ infants (MDI 85 to 116) for 20 of 25 items. Attention to linguistic and auditory milestones early in infancy can contribute to the early detection and diagnosis of mental retardation and disorders of communication.

Arginine-responsive asymptomatic hyperammonemia in the premature infant

We found that more than 50% of premature infants have elevated plasma ammonium levels during the first 2 months of life. Ammonium levels were twice normal and were unaccompanied by clinical symptoms of vomiting or lethargy. Ten of these infants were given supplements of arginine (1 to 2 mmol/kg/day PO) for 1 to 2 weeks preceded and followed by control periods. In each infant, plasma ammonium levels fell significantly within 2 days of start of arginine supplementation, and increased once arginine was discontinued. We studied 59 additional premature infants, of whom 26 had normal ammonium levels and 33 were hyperammonemic. Plasma arginine and ornithine levels were significantly lower in the hyperammonemic group, but there was no difference in urinary excretion of arginine or ornithine between groups. Half of the hyperammonemic infants received arginine supplementation between 2 and 8 weeks of age. Plasma ammonium levels in the arginine group was 33 + 1 mumol/L., compared to 45 + 2 mumol/L in the untreated group. Follow-up at 18 months of age showed similar IQ scores in all groups, suggesting that significant neurologic deficits do not result from this transient metabolic defect. The mechanism of the hyperammonemia is unclear.

Motor Functions: Associated Primitive Reflex Profiles

The results of reflex/motor activity interactions in 177 normal infants are evaluated. The asymmetrical tonic neck reflex, tonic labyrinthine reflex‐supine, and Moro reflexes were assessed for each child at birth and at intervals up to 12 months. Ages of rolling prone to supine, rolling supine to prone, and sitting alone were elicited from parents. The effects of the primitive reflexes on early motor activity were assessed, and statistically significant correlations were demonstrated between decreased reflex activity and the emergence of motor milestones. The distinctive association of reflex activity with motor function suggests the interaction of several reflexes (a primitive reflex profile) rather than the influence of isolated reflex activity. Such patterns support the hypothesis that decreasing primitive reflex activity is associated with the onset of volitional motor activity in normal infants.

Issues in the early identification of specific learning disability

Currently the diagnosis of Specific Learning Disability (SLD) requires the demonstration of academic underachievement relative to cognitive potential. However, if the focus is shifted from academic underachievement to the detection of the deviant neurologic substrate, then the potential exists for diagnosing SLD prior to school. Circumstantial evidence from a variety of sources—studies of historical risk, the newborn examination, assessment of newborn behaviors, combination of newborn and subsequent examination, retrospective assessment of early development in SLD children, and aspects of infant development (motor or language) and SLD—suggests that the neurologic substrate for SLD can be identified in infancy. Early identification of SLD will permit early intervention when indicated, aid the assessment of therapeutic efficacy, and facilitate the evaluation of other interventions (e.g., neonatal care).

DETECTING DELAY IN PREMATURE INFANTS: THE NEED FOR PARTIAL CORRECTION. † 1683

While premature infants are generally regarded as at high risk for developmental delay, and many early intervention programs are specifically targeted toward premature infants, there is a general consensus that: 1. full age adjustment is necessary (to compensate for prematurity), and 2. developmental delay cannot be detected accurately for several years due to extreme variability in delayed infants or their test results. In this study, 44 premature infants (mean gestational age 29.0 weeks, mean birthweight 1291 grams) were evaluated for suspected developmental delay at least twice, using the Bayley Scales of Infant Development Mental Development Index, in a high risk infant follow-up clinic. Mean age at initial testing was 12.8 months and at follow-up testing was 27.6 months. T-tests and linear regression were used to evaluate the effects of age adjustment at initial testing upon later developmental scores. Results obtained showed that: 1. 50% correction for prematurity produced the most consistent developmental test scores over time 2. both full correction and no correction produced scores that were significantly different than later developmental measures (mean difference from test 1 to test 2 +8.1 to -11.8, t values 2.40 and 2.10, p=0.02 and 0.04, respectively) 3. when 50% correction was used, developmental scores were remarkably consistent over time, and accurately predicted developmental delay. It is recommended that clinicians utilize 50% age adjustment when evaluating premature infant development.

THE EXPANDED NEUROLOGIC EXAMINATION (ENE): DOES IT HELP?

To test if the ENE would Improve identification of developmental dysfunction (DD), a standard ENE was administered to 275 5-year-olds. Psychologic and education tests were administered concurrently. The ENE covered five areas: 1) Behavioral-Hyperactivity, 2) Soft Signs, 3) Hard Signs, 4) Visual Motor, and 5) Language Memory. Area scores were derived by adding normalized values of individual test items, Three adverse outcomes which did not depend on ENE area scores were defined: Delay in cognition or academic unreadiness; Discrepancy between language and visual motor development; Clinical impression of neurologic abnormality. A discriminant function approach was used to find weights for combinations of area scores as predictors of adverse outcomes. Classification errors were converted to sensitivity and specificity and are shown for delay in cognition or academic unreadiness.Although the ability of the full ENE to classify children was good for all three adverse outcomes, using all five areas did not substantially improve error rates over single areas. No single area in the ENE was consistently superior to any other.The data support the idea that DD in 5-year-olds is pervasive, and that full evaluations may be unnecessary for identification.

THE RELATIONSHIP BETWEEN COGNITIVE AND GROSS MOTOR DEVELOPMENT

The age of motor milestone achievement, collected in a prospective fashion during well baby examinations, was compared to the 3 year old Stanford Binet (SB) performance for 213 caucasian children. The population had 109 males and 104 females, was predominantly upper middle class (Hollingshead ≤3 for 205), and included 4 prematures. Mean SB IQ was 114 ±13 with 32 children 100. Milestones included: rolls supine to prone (S to P), sits (alone), crawls and walks. Mean ages of attainment in months and standard deviations are tabled. Milestones were related to SB performance using linear correlation. Pearsons r values are shown. To determine whether significant relationships existed when IQ stratification (IQ<85, 85-100, 101-117, >117) was considered, milestones were regressed on SB groups. The t statistics refer to regression coefficients in this analysis.Significant but modest correlations exist between the ages of motor achievement and SB performance. This also holds when stratifying by IQ subgroups. Brighter children have earlier ages of gross motor achievement; however, this relationship is not strong enough to clinically discern SB subgroups.

61 BEHAVIORAL MEDICINE ASSESSMENT IN DySTONIA MUBOULORUM DEFORMANS

The assessment of movement disorders necessitates the quantification of abnormal findings. The development of behavior analysis techniques offers a methodology for examining movements. The present study is an attempt to apply behavior analysis techniques to the treatment of disorders. Three patients with Dystonia Musculorum Deformans (age range 16-24y ) were assessed during treatment with artane (8-15mg/d),parsidol (200-400mg/d) (P), tegretol (.4-1.5mg/d) (T) or P+T. The results in one patient are shown. Assessment measures including range of motion, finger dexterity, writing skills, and surface EMG suggests the greatest improvement is on a combination of P+T. This approach suggests that assessment of behavioral changes may provide important information upon which to base clinical decisions. Empirical analysis of behaviors represents a methodology by which treatment efficacy may be quantified and clinical impressions substantiated.

87 LINGUISTIC DEVELOPMENT BETWEEN 12 AND 24 MONTHS: A COGNITIVE PREDICTOR

The ages of attainment of expressive language milestones were elicited from parents of 96 middle class children at each well child visit from birth to 24 months. Mean frequency of milestone recall was 83%. Stanford Binet (SB) and Peabody Picture Vocabulary Tests (PPVT) were administered at 36 months of age: IQscores (mean ± SD) were 114 ± 11 and 112 ± 14, respectively. Pearson product-moment correlation coefficients between each milestone and test are noted in the Table.The ages of attainment of these milestones show a significant inverse correlation, p<.05, with three-year cognitive and language ability. Similar significant correlations were noted with the Vineland, Griffith and subtests of the McCarthy Scales. Sequential milestones of increasing vocabulary sizeand phrase complexity under two years can aid in early prediction of intellectual function.