Perceptual, motor and attentional deficits in seven-year-old children: background factors

A systematic review of behavioral and neurobiological profiles associated with coexisting attention-deficit/hyperactivity disorder and developmental coordination disorder

Attention-deficit/hyperactivity disorder (ADHD) and developmental coordination disorder (DCD) co-occur in approximately 50% of cases. This study aimed to characterize the behavioral, cognitive, and neurobiological profiles of co-occurring ADHD and DCD diagnoses by mapping, synthesizing, and providing a critical appraisal of the existing literature. A systematic search was conducted across four databases (MEDLINE, PsycINFO, Embase, and Scopus) to identify studies comparing a coexisting ADHD+DCD diagnosis to ADHD and DCD alone. From 2353 screened articles, 15 behavioral and 10 neuroimaging studies were included. Collectively, these studies suggest that the comorbid ADHD+DCD presentation constitutes a more severe phenotype characterized by neurocognitive differences associated with both conditions. Despite sharing some common neural features, our findings support the separate etiology hypothesis indicating that neural network alterations in individuals with ADHD+DCD represent a unique neural pattern rather than a sum of ADHD and DCD characteristics. Considering the heterogeneity inherent to both ADHD and DCD, future studies should involve rigorous and comprehensive assessment procedures to delineate how different subtypes of each diagnosis relate to distinct performance characteristics.

Prevalence of Developmental Co-ordination Disorder in School Children

Developmental co-ordination disorder (DCD) is a hidden complex childhood disorder seen in school aged children. There are only few Indian literatures supporting the prevalence of DCD among Indian school children but this current research has attempted to make a confirmatory diagnosis of DCD. Objective of the study was to estimate the prevalence rate of DCD among school children. This study was designed as cross-sectional study; sample size was 944 students. Outcome measure used was Diagnostic and Statistical Manual of Mental Disorders fifth edition (DSM V) criteria. On screening 944 children the overall prevalence rate was 3.8% (36). The gender wise distribution showed more male children were affected compared to female children. Age wise distribution showed a higher prevalence rate between the age group 9 to 14 y. This study yielded a comprehensive, well controlled overview in the prevalence of DCD, therefore early diagnosis is now a great concern and areas of theoretical, and clinical importance should be considered.

VISIT-TS: A multimedia tool for population studies on tic disorders

Population-based assessment of Tourette syndrome (TS) and other tic disorders produces a paradox. On one hand, ideally diagnosis of tic disorders requires expert observation. In fact, diagnostic criteria for TS explicitly require expert assessment of tics for a definite diagnosis. On the other hand, large-scale population surveys with expert assessment of every subject are impracticable. True, several published studies have successfully used expert assessment to find tic prevalence in a representative population (e.g. all students in a school district). However, extending these studies to larger populations is daunting.

We created a multimedia tool to demonstrate tics to a lay audience, discuss their defining and common attributes, and address features that differentiate tics from other movements and vocalizations. A first version was modified to improve clarity and to include a more diverse group in terms of age and ethnicity. The result is a tool intended for epidemiological research. It may also provide additional benefits, such as more representative minority recruitment for other TS studies and increased community awareness of TS.

Executive function and attention in young adults with and without developmental coordination disorder--a comparative study

The current research aimed at examining the executive function (EF) of young adults with Developmental Coordination Disorder (DCD) in comparison to young adults without DCD. The study used a randomized cohort (N=429) of young adults with DCD (n=135), borderline DCD (n=149) and control (n=145), from a previous study. This initial cohort was asked to participate in the current study three to four years later. Twenty-five individuals with DCD (mean age=24 years, 1 month [SD=0.88]; 18 males), 30 with borderline DCD (mean age=24 years, 2 month [SD=0.98]; 18 males) and 41 without DCD (mean age=25 years, 2 months [SD=1.91]; 20 males) participated in this study. Participants completed the BRIEF-A questionnaire, assessing EF abilities and the WURS questionnaire, assessing attention abilities. The DCD and borderline DCD groups had significantly lower EF profiles in comparison with the control group but no significant differences were found between the DCD and borderline DCD groups. While a high percentage of attention problems were found in both DCD groups, the executive functioning profiles remained consistent even when using the attention component as a covariate. The study results suggest that young adults with DCD have EF problems which remain consistent with or without attention difficulties.

Developmental delays in children with ADHD

OBJECTIVE

ADHD is often comorbid with other disorders, but it is often assumed that academic, language, or motor c skills problems are secondary to ADHD rather than that attention problems are secondary to the other disorder or both disorders have a shared etiology. We assessed for comorbid developmental disorders and which cognitive processes were impaired in children with ADHD.

METHOD

Measures of intelligence, language, motor skills, social cognition, and executive functions were administered to children with ADHD (n = 53) and age/sex-matched typical children.

RESULTS

Clinically significant deficits were 2 to 7 times as common in children with ADHD as in typical children, and the structure of ability differed in the two groups. Abilities were less differentiated in children with ADHD.

CONCLUSION

The results indicate a need for comprehensive screening for developmental disorders in children with ADHD and imply that research needs to focus on how ADHD and developmental disorders may share an etiology.

The relationship between parental concerns and final diagnosis in children with developmental delay

Parental concern is a useful screening approach for early detection of children with developmental delay. We investigated the relationships among parental concerns, functional impairment, and final diagnosis of children (n = 273) with developmental delays. Of these, motor, language, and global delay were most common. Parental concerns, especially in language and motor development, were good predictors of children with language or motor delay, and provided reliable information for detection of children with delays in these domains. Parents were less likely to identify children with cognitive problems, global delay, or associated behavioral problems. Co-occurrence of developmental disorders was also recognized, especially in children with global delay. We conclude that parental concerns are useful information for detection of specific developmental problems in children. Because co-occurrence of developmental disorders is common, their early recognition would be helpful for better care of these children.

An immunoreactive theory of selective male affliction

Males are selectively afflicted with the neurodevelopmental and psychiatric disorders of childhood, a broad and virtually ubiquitous phenomenon that has not received proper attention in the biological study of sex differences. The previous literature has alluded to psychosocial differences, genetic factors and elements pertaining to male “complexity” and relative immaturity, but these are not deemed an adequate explanation for selective male affliction. The structure of sex differences in neurodevelopmental disorders is hypothesized to contain these elements: (1) Males are more frequently afflicted, females more severely; (2) disorders arising in females are largely mediated by the genotype; in males, by a genotype by environment interaction; (3) complications of pregnancy and delivery occur more frequently with male births; such complications are decisive and influence subsequent development. We hypothesize that there is something about the male fetus that evokes an inhospitable uterine environment. This “evocative principle” is hypothesized to relate to the relative antigenicity of the male fetus, which may induce a state of maternal immunoreactivity, leading either directly or indirectly to fetal damage. The immunoreactive theory (IMRT) thus constructed is borrowed from studies of sex ratios and is the only explanation consistent with negative parity effects in the occurrence of pregnancy complications and certain neurodevelopmental disorders. Although the theory is necessarily speculative, it is heuristic and hypotheses derived from it are proposed; some are confirmed in the existing literature and by the authors' research.

Psychopathology in a Swedish population of school children with tic disorders

OBJECTIVE

To examine patterns of psychiatric comorbid disorders and associated problems in a school population of children with tic disorders.

METHOD

From a total population of 4,479 children, 25 with Tourette's disorder (TD), 34 with chronic motor tics (CMT), 24 with chronic vocal tics (CVT), and 214 with transient tics (TT) during the past year were found. A three-stage procedure was used: tic screening, telephone interview, and clinical assessment. The TD group was compared with 25 children with TT and 25 controls without tics.

RESULTS

Psychiatric comorbid disorders were found in 92% of the children with TD. Attention-deficit/hyperactivity disorder was most common, and patterns of psychiatric comorbidity were similar in children with TD and CVT, but not with CMT and TT. Aggressive behavior was more common in children with TD than other tic disorders.

CONCLUSIONS

Psychiatric comorbid disorders are common even in community-based samples of children with TD and CVT. TD and CVT seem to be part of the same disease entity, with TD being a more severe form. Chronic tics may be a marker for behavioral and learning difficulties in children, and awareness of these associations is critical to the care and treatment of children with tics.

Tourette syndrome and other tic disorders in a total population of children: clinical assessment and background

AIM

To describe the symptoms, onset, heredity, pre-/perinatal events and socio-economic status in Tourette syndrome (TS) and other tic disorders.

METHODS

From a total population of 4479 children, 25 (0.6%) with TS, 58 (1.3%) with chronic motor/vocal tics (CMVT) and 214 (4.8%) with transient tics (TT) in the last year were found. A three-stage procedure was used: tic screening, telephone interview and clinical assessment. The TS group was compared with 25 children with TT and 25 controls without tics.

RESULTS

The mean age of the first symptoms of TS was significantly lower than the onset of CMVT. All except one with TS had contact with medical services. The tics of children with TS were significantly more severe than the tics of others. Younger age of onset of TS indicated more severe tics. Parents and siblings of children with TS had an increased prevalence of tic disorders, obsessive-compulsive behaviour (OCD), attention-deficit/hyperactivity disorder (ADHD) and depression. Eighty per cent had a first-degree relative with a psychiatric disorder. A non-significant increase with regards to reduced optimality score in the pre-, peri- or neonatal periods was found in children with TS compared to controls. No differences were found concerning socio-economic status.

CONCLUSION

Almost all children from a total population with TS have sought help from medical services. An increased prevalence of tics, OCD, depression or ADHD was found in the parents/siblings of children with TS, which draws attention to the importance of thorough investigation of family members.

Motor flexibility problems as a marker for genetic susceptibility to attention-deficit/hyperactivity disorder

BACKGROUND

Since many children with attention-deficit/hyperactivity disorder (ADHD) have fine visuomotor problems that are already evident at a young age, motor dysfunctioning is investigated in family-genetic perspective. We hypothesized that if fine motor problems may be a marker for genetic susceptibility to ADHD, nonaffected siblings of ADHD probands would experience motor problems similar to those of their ADHD siblings.

METHODS

Twenty-five carefully phenotyped ADHD probands with a family history of ADHD, their nonaffected siblings (n = 25), and 48 normal control subjects (aged 6 to 17) completed a motor fluency task and a motor flexibility task. The motor fluency task involved completion of a familiar, automatized trajectory, whereas the motor flexibility task required continuous adjustment of movement to complete an unpredictable random trajectory.

RESULTS

On the motor fluency task, the performance of the nonaffected children was significantly better than that of the ADHD probands; strikingly, on the motor flexibility task, they performed as well as their ADHD siblings.

CONCLUSIONS

Nonaffected siblings experience complex motor problems similar to their ADHD siblings but only in nonautomatized movements that require controlled processing. The results suggest that higher-order controlled motor deficits in ADHD may be associated with genetic susceptibility for ADHD.

Practitioner review: approaches to assessment and treatment of children with DCD: an evaluative review

BACKGROUND

Movement clumsiness (or Developmental Coordination Disorder--DCD) has gained increasing recognition as a significant condition of childhood. However, some uncertainty still exists about diagnosis. Accordingly, approaches to assessment and treatment are varied, each drawing on distinct theoretical assumptions about the aetiology of the condition and its developmental course.

METHOD

This review evaluates the current status of different approaches to motor assessment and treatment for children with DCD. These approaches are divided according to their broad conceptual origin (or explanatory framework): Normative Functional Skill Approach, General Abilities Approach, Neurodevelopmental Theory, Dynamical Systems Theory, and the Cognitive Neuroscientific Approach.

CONCLUSIONS

Each conceptual framework is shown to support assessment and treatment methods with varying degrees of conceptual and psychometric integrity. The normative functional skill approach supports the major screening devices for DCD and cognitive (or top-down) approaches to intervention. The general abilities approach and traditional neurodevelopmental theory are not well supported by recent research. The dynamical systems approach supports promising trends in biomechanical or kinematic analysis of movement, ecological task analysis, and task-specific intervention. Finally, and more recently, the cognitive neuroscientific approach has generated some examples of process-oriented assessment and treatment based on validated (brain-behaviour) models of motor control and learning. A multi-level approach to movement assessment and treatment is recommended for DCD, providing a more complete representation of motor development at different levels of function--behavioural, neurocognitive, and emotional.

Motor co-ordination in a South Indian population of children

AIMS

To examine the associations of motor co-ordination in Kerala, South India.

METHODS

The Modified Oseretsky Test of motor co-ordination was administered to 1155 representative children during a door-to-door survey of 8-12 year olds. Reading, vocabulary and visuospatial reasoning were measured, as were height and weight. Information on medical history, socio-demographic background and behaviour was systematically collected.

RESULTS

Age was the major association of motor incoordination indicating the importance of maturation. Behaviour, vocabulary, visuospatial reasoning, material deprivation, perinatal complications, chronic physical symptoms and occupational status of the father were also independently associated with motor co-ordination. Using sibling pairs, evidence of familial aggregation of motor co-ordination was found.

Social risk factors as predictors for parental report of deviant behaviour in 3-year-old children

The objective of this study was to examine whether social risk factors adjusted for gender and some well-known perinatal risk factors were related to parental descriptions of deviant behaviour in 3(1/2)-year-old children. The study was a prospective cohort study of 1345 mothers enrolled during early pregnancy. Parents answered a questionnaire and children's behavioural difficulties were categorized into the following groups; "hyperactive-distractible", "hostile-aggressive" and "anxious-fearful" following a modified Behar scale. The male gender was found to be related to a description of all kinds of deviant behaviour. Having a family member experiencing employment difficulties was the factor most closely related to "hyperactive-distractible" behaviour. Familial stress due to lack of time, experience of divorce and mothers in excess of 35 years at childbirth were found to be related to "hostile-aggressive" behaviour, but male gender was the most closely related. Social disadvantage was not found to be related to "anxious-fearful" behaviour.

Developmental coordination disorder: a review of research on subtypes and comorbidities

The interest in Developmental Coordination Disorder (DCD) has grown considerably over the last decade. Nevertheless, its etiology and prognosis are still poorly understood. The idea is growing that DCD may not be a uniform disorder. This review summarizes research on DCD, with a particular focus on subtype and comorbidity studies. The main message of the paper is that, in order to understand the etiology and prognosis of DCD, we need to have a better understanding of its nature. This requires an awareness of the existence of subtypes and comorbidities. Current theories on comorbidity phenomena are discussed in terms of their possible merit for the development of the field. Particular attention is given to the Automatization Deficit Hypothesis, a theory based on research on dyslexia.

Deficits in attention, motor control, and perception: a brief review

The concept of DAMP (deficits in attention, motor control, and perception) has been in clinical use in Scandinavia for about 20 years. DAMP is diagnosed on the basis of concomitant attention deficit/hyperactivity disorder and developmental coordination disorder in children who do not have severe learning disability or cerebral palsy. In clinically severe form it affects about 1.5% of the general population of school age children; another few per cent are affected by more moderate variants. Boys are overrepresented; girls are currently probably underdiagnosed. There are many comorbid problems/overlapping conditions, including conduct disorder, depression/anxiety, and academic failure. There is a strong link with autism spectrum disorders in severe DAMP. Familial factors and pre- and perinatal risk factors account for much of the variance. Psychosocial risk factors appear to increase the risk of marked psychiatric abnormality in DAMP. Outcome in early adult age was psychosocially poor in one study in almost 60% of unmedicated cases. There are effective interventions available for many of the problems encountered in DAMP.

Early parent-child relations and family functioning of preschool boys with pervasive hyperactivity

This study examined the quality of parent-child relationships and family functioning of preschool children with early onset hyperactivity by comparing a community sample of 33 pervasively hyperactive preschool boys with a comparison sample of 34 boys. Mothers and children were assessed at home on a range of interview, parent questionnaire, and observational measures of parenting and family functioning. Results of the study showed that higher rates of reported lax disciplinary practices, less efficient parental coping, lower rates of father-child communication, and less synchronous mother-child interactions were significantly associated with hyperactivity following statistical adjustment for the effects of conduct problems and other confounding factors. The best parenting predictor of hyperactivity was maternal coping. The present findings suggest that the way in which parents interact with their preschool children may make a unique contribution to the development and ongoing behavioral difficulties experienced by children with pervasive hyperactivity. Findings also highlight the importance of considering the role of fathers in the behavioral development of boys with early tendencies to hyperactive and distractible behavior problems.

Optimality of the birth population reduces learning and behaviour disorders and sudden infant death after the first month

The weight distribution pattern of all births can be divided into a "skewing to the left" to lower weights and high neonatal mortality, a "skewing to the right" to higher weights (>3500g) and minimum neonatal and postneonatal mortality, and a "symmetrical distribution" with mortality in between. This study was initiated with the hypothesis that a deficit in newborns of more than 3500 g would adversely affect postneonatal death. Higher and rising postneonatal mortality solely attributable to sudden infant death of unknown cause (sudden infant death syndrome; SIDS) was observed in the Nordic countries with a lower proportion of heavy newborns. Minor environmental intervention almost eliminated excess mortality from this cause, supporting raised susceptibility with a depressed birthweight in postneonatal SIDS. This contrasts with classical neonatal low birthweight SIDS, which is stable despite numerous attempts at reduction, supporting a multi-factorial aetiology: low maternal age, low education, low socioeconomic status, maternal smoking, infection, etc. The postneonatal SIDS epidemic associated with a deficit in heavy newborns is thought to be a result of changing behaviour in pregnancy: moderate iatrogenic dietary restriction and young women favouring a low-calorie, low-fat diet, especially in the third trimester when the foetus is most vulnerable, which delays myelination and somatic growth and renders the infant susceptible to minor morbidity and irregularity. The timing of death and neuropathological findings suggestive of repeated hypoxic episodes in more than 80% of cases of SIDS prior to death support this theory. The similar weight distribution patterns in SIDS and all births in Denmark, the UK and the USA suggest a substantial proportion of the neonates in these countries could be growth-retarded and at risk of hypoxic episodes in infancy. A few cases, particularly males (sex-ratio = 1.7), suffer SIDS, the majority survive. Many, mostly males, present minor CNS signs and learning and behaviour problems. The male predominance accords with males more than 500 g higher optimal birthweight than females and susceptibility to a depressed weight at birth. In order to prevent postneonatal dying, SIDS and reduce learning/behaviour disorders it is necessary to raise the proportion of heavy newborns by promoting foetal growth rate equal to the maternal intrinsic rate by eating to one's appetite a balanced diet, favouring a diet high in marine fat, especially in third trimester, in order to ensure maturation of the CNS and prolong gestation, thereby increasing birthweight. Although the increased survival of some very low birthweight neonates confounds the issue, a division between SIDS in neonatal and postneonatal death is recommended in order to assess the proportion of "avoidable infant death" as opposed to persistent classical neonatal SIDS.

Attention deficits and clumsiness in Swedish 7-year-old children

A population study of 409 seven-year-old children in a middle-sized Swedish town was performed. All children were examined by the same doctor and evaluated by means of parent interview, motor examinations, and teacher reports on behaviour in the classroom. Follow-up was carried out 8 months later. The rate of severe problems in the fields of attention deficit-hyperactivity disorder (ADHD), developmental coordination disorder (DCD), and deficits in attention, motor control, and perception (DAMP) (the combination of ADHD and DCD) was 6.1%, with boys being affected more frequently than girls. There was considerable overlap between ADHD and DCD, with about half of each diagnostic group also meeting criteria for the other diagnosis. Attention deficits at diagnosis strongly predicted attention deficits at follow-up. If parents had noted attention deficits in the home setting, then teachers almost always independently agreed that there were similar problems in the classroom. However, the reverse did not always apply. Clumsiness also showed striking stability over time. The diagnosis of DAMP, particularly severe DAMP, had a stronger association with classroom dysfunction and with high Conners scores than did diagnoses of ADHD or DCD. It is concluded that DAMP may be a clinically valid diagnostic construct.

Familial factors in anorexia nervosa: a community-based study

A group of 51 cases with teenage anorexia nervosa (AN; including a total population of cases from one birth cohort) were compared with a sex-, age-, and school-matched group of 51 cases on familial factors. The subjects were examined at age 16 and 21 years. In the first study, mothers of both groups were interviewed regarding physical and psychiatric disorders among first-degree relatives. In the followup study, the subjects were interviewed according to the same structured interview schedule. The data from these interviews were deidentified, and case notes were prepared by a clinician blind to group status. The randomly assorted case notes were then submitted to an experienced psychiatrist who also was blind to group status. There were more relatives with a history and symptoms suggestive of pervasive developmental disorders (PDD) and major depression in the AN group. There was also significantly more death in first-degree relatives of anorexia nervosa cases. In respect to many axis I DSM-IV diagnoses, including eating disorders and substance abuse, there were no significant differences across groups. Instead we found PDD symptoms, major depression, and death in first-degree relatives to be important in the AN group.

Attention deficit disorder with developmental coordination disorders

AIMS

To analyse the contribution of certain social, familial, prenatal, perinatal, and developmental background factors in the pathogenesis of deficits in attention, motor control, and perception (DAMP).

METHODS

A population based case-control study was carried out with 113 children aged 6 years, 62 diagnosed with DAMP and 51 controls without DAMP. The children's health and medical records were studied and their history with regard to background factors was taken at an interview with the mother using a standardised schedule. Familial factors, possible non-optimal factors during pregnancy (including smoking), developmental factors (including early language development), and medical and psychosocial data were scored in accordance with the reduced optimality method.

RESULTS

Low socioeconomic class was common in the group with DAMP. Familial language disorder and familial motor clumsiness were found at higher rates in the DAMP group. Neuropathogenic risk factors in utero were also more common in the children with DAMP. Maternal smoking during pregnancy appeared to be an important risk factor. Language problems were present in two thirds of the children with DAMP. Sleep problems and gastrointestinal disorders, but not atopy or otitis media, were significantly more common in the DAMP group.

CONCLUSIONS

Prenatal familial and neuropathogenic risk factors contribute to the development of DAMP. Primary prevention, such as improved maternal health care and early detection or treatment, or both, of associated language problems appear to be essential.

Obstetric and perinatal factors as predictors of child behaviour at 5 years

OBJECTIVE

To identify whether obstetric and perinatal factors are independent predictors of child behaviour at 5 years.

METHODOLOGY

The Mater University Study of Pregnancy (MUSP) is a prospective cohort study of 8556 mothers enrolled in early pregnancy. The relationship of obstetric and perinatal factors, maternal lifestyle, age and gender of the child, and social disadvantage were examined as predictors of child behaviour in 5005 children completing a modified child behaviour checklist at 5 years. This checklist contained three independent groups of behaviour: externalizng, internalizing and SAT (social, attentional and thought problems).

RESULTS

In the initial analysis a limited number of associations were present. After adjusting for measures of social disadvantage, only number of antenatal admissions was associated with child behaviour in all three scales, while maternal cigarette smoking in pregnancy and male gender were associated with externalising and SAT behaviours.

CONCLUSIONS

Most common epidemiologic obstetric and perinatal risk factors were not independent predictors of behaviour problems in children at 5 years.

Optimal foetal growth in the reduction of learning and behaviour disorder and prevention of sudden infant death (SIDS) after the first month

A theory is presented that a diet low in polyunsaturated fatty acids (PUFA) in the third trimester of pregnancy may delay myelination and brain maturation. This may underpin learning and behaviour disorders and sudden infant death (SIDS) after the first month, conditions that are associated with lower than average birthweight. Epidemiological evidence is reviewed showing an inverse relation between the proportion of heavy newborns (> 3500 g) and infant mortality rate. Some countries with a lower proportion of heavy newborns despite equally high standards of living and medical care have higher post-neonatal death rates. The higher rates are solely due to SIDS which has a peak mortality within 80-100 days. It is hypothesised that as this is a time when myelination peaks, SIDS may be due to maturational delay. Evidence of subtle CNS changes in brainstem structures and in the neuromuscular system supports an instability in brainstem control systems. Moderate iatrogenic dietary restriction predominates today, but a rising number of women favour a low-caloric low-fat diet especially in the third trimester when the foetus is most susceptible. This may lead to a depressed birthweight, delayed somatic growth and neuronal maturation, such as is observed in SIDS victims. The majority exposed to suboptimal conditions survive, but a few suffer SIDS; confirming post-neonatal susceptibility. Many, especially males, present minor CNS signs and learning/behaviour disorders that could be the sequelae of repeated hypoxic episodes, such as recorded in more than 80% of SIDS victims. To reduce learning/behaviour disorders and prevent death from SIDS after the first month, it is necessary to ensure optimal development by promoting foetal growth. It is advised to avoid unnecessary dieting and to favour a diet high in PUFAs, thus prolonging pregnancy and so increasing birthweight.

A review of neuromotor tests and the construction of a scored neuromotor examination for four-year-olds

We have reviewed the methodologies in construction of some widely used tests and constructed a computer-compatible scored method for the neuromotor evaluation of four year olds. Using the data from 333 neurological assessments, factor analysis indicated five subscales. Alpha coefficients show high reliability for both subscales and total scores. Using data from a second sample, we describe predictive validity for the five subscales and total score.

Screening methods, epidemiology and evaluation of intervention in DAMP in preschool children

This report describes a population-based study of deficits in attention, motor control and perception (DAMP) in six-year-old Swedish urban children. The point prevalance was 2.8% and the boy:girl ratio 5.3∶1. A questionnaire and motor examination screening device is described and evaluated. In a group of 25 children with DAMP, interventions of various kinds were made when the children were 6-7 years old. These cases were followed up at age 10-11 years and compared with 42 cases who had received no intervention. The follow-up study was fraught with problems and the data obtained could only be used for highly preliminary conclusions. However, it appears that information to parents, children and teachers about the nature of the child's condition might be helpful.

Hyperactivity and altered amphetamine sensitivity in premature juvenile rats

'Premature' rats that were delivered by cesarean section on day 21 of gestation and 'normal' rats that were delivered spontaneously on day 22 of gestation were tested for basal locomotor activity and locomotor stimulation in response to D-amphetamine at 19-21 days of age. Compared to normal rats, premature rats had increased basal levels of locomotor activity and showed enhanced sensitivity to the locomotor stimulant effects of D-amphetamine. Cesarean-delivered premature rats may be a useful animal model for investigating mechanisms of neurobehavioral deficits associated with premature birth in humans.

Effect of very low birth weight and subnormal head size on cognitive abilities at school age

BACKGROUND

We tested the hypothesis that very-low-birth-weight (less than 1.5 kg) infants with perinatal growth failure whose head size is not normal by eight months of age (corrected for prematurity) have significantly poorer growth and neurocognitive abilities at school age than very-low-birth-weight children with a normal head size at eight months. We also hypothesized that these differences would persist even after control for major neurologic impairment and perinatal and sociodemographic risk factors.

METHODS

We have followed a cohort of very-low-birth-weight children since their birth during the period 1977 to 1979. At eight to nine years of age 249 children were evaluated with a neurologic examination and tests of intelligence; receptive and expressive language skills; speech, reading, mathematics, and spelling aptitude; visual and fine motor abilities; and behavior. Ages were corrected for premature birth.

RESULTS

Among these 249 very-low-birth-weight children, head size was subnormal (less than the mean -2 SD for age) at birth in 30 (12 percent), at term in 57 (23 percent), and at eight months in 33 (13 percent). As compared with the 216 children with normal head sizes, the 33 children with subnormal head sizes at the age of eight months had significantly lower mean birth weights (1.1 vs. 1.2 kg) and higher neonatal risk scores (71 vs. 53) and at the age of eight years had a higher incidence of neurologic impairment (21 percent vs. 8 percent) and lower IQ scores (mean verbal, 84 vs. 98). Even among the children without neurologic abnormalities, a subnormal head size at eight months of age was predictive of poorer verbal and performance IQ scores at eight years of age; lower scores for receptive language, speech, reading, mathematics, and spelling; and a higher incidence of hyperactivity. In multiple regression analyses to control for socioeconomic and neonatal risk factors, intrauterine growth failure, birth weight, and neurologic impairment, a subnormal head size at eight months of age had an independently adverse effect on IQ and on scores for receptive language, speech, reading, and spelling.

CONCLUSIONS

In very-low-birth-weight infants, perinatal growth failure, as evidenced by a subnormal head circumference at eight months of age, is associated with poor cognitive function, academic achievement, and behavior at eight years of age.

Specific learning disorders: the possible role of brain damage

The causes of many of the more subtle disorders of cerebral function are often obscure. Are they due to impaired development of the brain or to damage to the brain? Particularly if there is no definite evidence of the latter, and when talking to parents, it is better to use such terms as "minimal cerebral dysfunction". However this must not lesson in any way the constant search for the etiology of these disorders. There is no doubt about their frequency, and in one form or another, about one in ten children have special educational needs. There is therefore a major medical contribution to be made to the problems of these children, especially in terms of prevention. A review of the literature shows, among other causes, how often episodes during pregnancy and birth can lead to learning problems during school life. In the future the development of new neuroradiological, and other techniques, will help to explain these common disabilities.

Significance of ultrasound appearances in the neurological development and cognitive abilities of preterm infants at 5 years

The developmental outcome at 5 years of age was studied in 93 preterm infants who had been prospectively examined for peri-ventricular leucomalacia (PVL). Standardised neurological examination and developmental assessment, including tests of cognitive function, were carried out. Major sequelae (n = 10) could be ascribed in most cases to the presence of large PVL lesions. Children with normal scans (n = 51), with isolated haemorrhage (n = 15) and with post-haemorrhagic ventricular dilatation (n = 3) had a favourable prognosis. Patients with small focal PVL changes (n = 16) had lower cognitive abilities on the McCarthy scale and presented more abnormal neuromotor signs and more attention deficits when compared to children with normal scans and isolated haemorrhage. Small focal PVL changes seem therefore to interfere with development at 5 years of age and might represent a morphological marker of a more diffuse brain injury. This study demonstrated also the effect of socioeconomic status on outcome at the age of 5 years.

Complete evaluation of the child identified as a poor listener

With increasing awareness among educators of the importance of early identification of hearing impairment, growing numbers of children are being referred for evaluation when a teacher or day care supervisor perceives that a child is having difficulty listening. Some children who manifest difficulty listening in a pre-school play group or the classroom may have conductive or sensorineural hearing loss, while others have normal hearing with an underlying and yet-to-be-detected behavioral or psychoeducational disorder. This report presents suggestions for evaluation of the child referred for difficulty listening. The otologist should consider that a child may have an attention deficit disorder when results of initial audiologic assessment indicate there is no hearing loss or when the degree of hearing loss appears to be small in relation to the degree of inattentiveness that has been observed. The features of Attention-deficit Hyperactivity Disorder (ADHD) and Specific Developmental Disorder (SDD) are described, and illustrative case studies are presented. Clues to diagnosis are provided and a distinction between overlapping disorders is made.

Attention deficit disorder with hyperactivity among paediatric outpatients

Out of 1,000 children (aged 3-12 years) screened in a paediatric outpatient department over a 3 1/2-year period, 112 were found to have attention deficit disorder with hyperactivity (ADDH). The prevalence of ADDH increased with age, from 5.2% in those aged 3-4 years, up to 29.2% in those aged 11-12 years. There were four times as many boys as girls with ADDH. ADDH was most common in first born children and those from a lower social class. Children with ADDH had a higher rate of complications during pregnancy and delivery relative to a comparison group. Delayed development, temper-tantrums, enuresis, tics, broken homes, persistent parental discord and psychiatric illness in parents were all more common in children with ADDH than in the comparison group.

Autism under age 3 years: a clinical study of 28 cases referred for autistic symptoms in infancy

Twenty-eight children referred with a preliminary diagnosis of autistic disorder under age 3 yrs were extensively examined from the neuropsychiatric point of view and followed up for several months to several years. A diagnosis of autistic disorder was confirmed in 75% of the cases. A variety of associated medical conditions was identified. It was concluded that autism can be diagnosed in a substantial proportion of cases before age 3 yrs and that the neurobiological background is similar to that seen in older autistic children.

Mental retardation in urban children: a population study of reduced optimality in the pre-, peri- and neonatal periods

One hundred and thirty representative cases of mentally retarded children in Sweden were surveyed in order to detect reductions in optimality in the prenatal, perinatal and postnatal periods. There was a small but statistically significant reduction in optimality, particularly pertaining to the prenatal and neonatal periods. It is of interest, however, that these mentally retarded children had smaller reductions of optimality than did children with cerebral palsy or infantile autism.

Neurological soft signs and school achievement: the mediating effects of sustained attention

A group of 115 black male adolescents drawn from a clinically unselected birth cohort, half of whom were known to have had neurological soft signs at age 7, were examined at age 17 to determine the relation between soft signs and performance on standard tests of school achievement and sustained attention. Three signs measured at age 17--dysgraphesthesia, difficulties with rapid alternating movements (dysdiadochokinesis), and motor slowness--were related to lower concurrent and past IQ and to impaired performance on laboratory and paper-and-pencil measures of sustained attention. The relation between signs and the attentional measures remained significant after IQ was statistically controlled. The three age 17 soft signs as well as age 7 signs were related to impaired performance on standardized tests (age 17) of school achievement. Most of the relation between signs and school achievement could be accounted for by the variance signs shared with sustained attention. One sign, mirror movements, was unrelated to all other attentional and cognitive measures.

Children with preschool minor neurodevelopmental disorders. IV: Behaviour and school achievement at age 13

A cohort of children with deficits in attention, motor control and perception at seven years, drawn from a total population sample of such children in Göteborg, Sweden, was compared at 13 years with a group of normal children with regard to behaviour and school achievement. The index group showed persisting high rates of severe behavioural problems, as judged by teachers', parents' and self-rating questionnaires. None had been treated with stimulants or other drugs to reduce the symptoms of their neurodevelopmental disorders. It seems that these children's problems were slightly less in the early teen years than they were at 10 years, but the rates were still much in excess of those in the comparison group.