Causes of infantile autism: some considerations from recent research

Genetic and environmental factors of schizophrenia and autism spectrum disorder: insights from twin studies

Twin studies of psychiatric disorders such as schizophrenia and autism spectrum disorder have employed epidemiological approaches that determine heritability by comparing the concordance rate between monozygotic twins (MZs) and dizygotic twins. The basis for these studies is that MZs share 100% of their genetic information. Recently, biological studies based on molecular methods are now being increasingly applied to examine the differences between MZs discordance for psychiatric disorders to unravel their possible causes. Although recent advances in next-generation sequencing have increased the accuracy of this line of research, there has been greater emphasis placed on epigenetic changes versus DNA sequence changes as the probable cause of discordant psychiatric disorders in MZs. Since the epigenetic status differs in each tissue type, in addition to the DNA from the peripheral blood, studies using DNA from nerve cells induced from postmortem brains or induced pluripotent stem cells are being carried out. Although it was originally thought that epigenetic changes occurred as a result of environmental factors, and thus were not transmittable, it is now known that such changes might possibly be transmitted between generations. Therefore, the potential possible effects of intestinal flora inside the body are currently being investigated as a cause of discordance in MZs. As a result, twin studies of psychiatric disorders are greatly contributing to the elucidation of genetic and environmental factors in the etiology of psychiatric conditions.

Big data approaches to decomposing heterogeneity across the autism spectrum

Autism is a diagnostic label based on behavior. While the diagnostic criteria attempt to maximize clinical consensus, it also masks a wide degree of heterogeneity between and within individuals at multiple levels of analysis. Understanding this multi-level heterogeneity is of high clinical and translational importance. Here we present organizing principles to frame research examining multi-level heterogeneity in autism. Theoretical concepts such as 'spectrum' or 'autisms' reflect non-mutually exclusive explanations regarding continuous/dimensional or categorical/qualitative variation between and within individuals. However, common practices of small sample size studies and case-control models are suboptimal for tackling heterogeneity. Big data are an important ingredient for furthering our understanding of heterogeneity in autism. In addition to being 'feature-rich', big data should be both 'broad' (i.e., large sample size) and 'deep' (i.e., multiple levels of data collected on the same individuals). These characteristics increase the likelihood that the study results are more generalizable and facilitate evaluation of the utility of different models of heterogeneity. A model's utility can be measured by its ability to explain clinically or mechanistically important phenomena, and also by explaining how variability manifests across different levels of analysis. The directionality for explaining variability across levels can be bottom-up or top-down, and should include the importance of development for characterizing changes within individuals. While progress can be made with 'supervised' models built upon a priori or theoretically predicted distinctions or dimensions of importance, it will become increasingly important to complement such work with unsupervised data-driven discoveries that leverage unknown and multivariate distinctions within big data. A better understanding of how to model heterogeneity between autistic people will facilitate progress towards precision medicine for symptoms that cause suffering, and person-centered support.

The Neurobiology of Infantile Autism

Early infantile autism is the most severe of a group of neurodevelopmental syndromes called the pervasive developmental disorders. The clinical features of autism vary greatly, but, by definition, include deficits in social relatedness, communication, and interests or routines. The onset of autistic signs and behaviors typ ically occurs in infancy, and the syndrome is usually fully present by the fourth year. The presence of mental retardation affects the clinical picture greatly. Severely autistic children may be retarded and mute and are often preoccupied with repetitive activities; they often exhibit motor stereotypes, such as rocking or hand flapping. They can be profoundly withdrawn and may show extreme aversion to social or physical contact. More mildly affected children may have normal or even superior intelligence, with well-developed language skills. Their deficits in social relatedness and preoccupation with rituals and routines may set them apart as very odd, but not necessarily as autistic. Autism occurs in 1 of 2000 live births; boys outnumber girls about 3 or 4:1. Although there are no localizing neurological signs in autism, mild or "soft" neurological signs are common and grand mal seizures are frequently present after puberty (Lotspeich LJ, Ciaranello RD. The neurobiology and genetics of infantile autism. In: Bradley R, editor. International reviews of neurobiology. San Diego: Academic Press 1993:87-129). The Neuroscientist 1:361-367, 1995

Identifying the lost generation of adults with autism spectrum conditions

Autism spectrum conditions comprise a set of early-onset neurodevelopmental syndromes with a prevalence of 1% across all ages. First diagnosis in adulthood has finally become recognised as an important clinical issue due to the increasing awareness of autism, broadening of diagnostic criteria, and the introduction of the spectrum concept. Thus, the idea of a lost generation of people who were previously excluded from a diagnosis of classic autism has arisen. Making a first diagnosis of autism spectrum conditions in adults can be challenging for practical reasons (eg, no person to provide a developmental history), developmental reasons (eg, the acquisition of learnt or camouflaging strategies), and clinical reasons (eg, high frequency of co-occurring disorders). The diagnostic process includes referral, screening, interviews with informants and patients, and functional assessments. In delineating differential diagnoses, true comorbidities, and overlapping behaviour with other psychiatric diagnoses, particular attention should be paid to anxiety, depression, obsessive-compulsive disorder, psychosis, personality disorders, and other neurodevelopmental disorders. Possible misdiagnosis, especially in women, should be explored. The creation of supportive, accepting, and autism-friendly social and physical environments is important and requires a coordinated effort across agencies and needs support from government policies.

Autism in flux: a history of the concept from Leo Kanner to DSM-5

In this paper, I argue that a new relation between past and present - a supposed historical continuity in the meaning of autism - is created by the histories written by the discipline itself. In histories of autism written by 'practitioner-historians', a sense of scientific progress and an essentialist understanding of autism legitimize and reinforce current understandings and research directions in the field of autism. Conceptual discontinuities and earlier complexities and disputes concerning classifying and delineating autism are usually left out of the positivist narrative of autism. In an alternative history of the concept of autism, I demonstrate that there have been major shifts in the type of symptoms, signs and impairments that were - and are - thought to be essential and specific for autism.

The effect of DSM-5 criteria on the developmental quotient in toddlers diagnosed with autism spectrum disorder

OBJECTIVE

To determine the effect of the changing fifth edition of the Diagnostic and Statistical Manual (DSM-5) criteria on the developmental profiles of children diagnosed with an Autism spectrum disorder (ASD).

METHODS

This study examines the effect of DSM-5 changes on impairment profiles of a population of 2054 at-risk toddlers aged 17-36 months using the Battelle Developmental Inventory, Second Edition.

RESULTS

Toddlers diagnosed with an ASD according to the DSM-5 were found to represent a more impaired population compared to those who qualified for a diagnosis of an ASD based on the DSM-IV-TR, but not the DSM-5. The group diagnosed according to the DSM-IV-TR represented a population of toddlers who were more impaired than atypically developing peers.

CONCLUSIONS

The proposed changes to the DSM will likely result in those diagnosed with an ASD according to the new criteria representing a more functionally impaired group. Implications of this proposed change are discussed.

Word learning in children with autism spectrum disorders

Autism spectrum disorders (ASD) have been gaining attention, partly as an example of unusual developmental trajectories related to early neurobiological differences. The present investigation addressed the process of learning new words to explore mechanisms of language delay and impairment. The sample included 21 typically developing toddlers matched on expressive vocabulary with 21 young children with ASD. Two tasks were administered to teach children a new word and were supplemented by cognitive and diagnostic measures. In most analyses, there were no group differences in performance. Children with ASD did not consistently make mapping errors, even in word learning situations that required the use of social information. These findings indicate that some children with ASD, in developmentally appropriate tasks, are able to use information from social interactions to guide word-object mappings. This result has important implications for understanding of how children with ASD learn language.

The CHARGE study: an epidemiologic investigation of genetic and environmental factors contributing to autism

Causes and contributing factors for autism are poorly understood. Evidence suggests that prevalence is rising, but the extent to which diagnostic changes and improvements in ascertainment contribute to this increase is unclear. Both genetic and environmental factors are likely to contribute etiologically. Evidence from twin, family, and genetic studies supports a role for an inherited predisposition to the development of autism. Nonetheless, clinical, neuroanatomic, neurophysiologic, and epidemiologic studies suggest that gene penetrance and expression may be influenced, in some cases strongly, by the prenatal and early postnatal environmental milieu. Sporadic studies link autism to xenobiotic chemicals and/or viruses, but few methodologically rigorous investigations have been undertaken. In light of major gaps in understanding of autism, a large case-control investigation of underlying environmental and genetic causes for autism and triggers of regression has been launched. The CHARGE (Childhood Autism Risks from Genetics and Environment) study will address a wide spectrum of chemical and biologic exposures, susceptibility factors, and their interactions. Phenotypic variation among children with autism will be explored, as will similarities and differences with developmental delay. The CHARGE study infrastructure includes detailed developmental assessments, medical information, questionnaire data, and biologic specimens. The CHARGE study is linked to University of California-Davis Center for Children's Environmental Health laboratories in immunology, xenobiotic measurement, cell signaling, genomics, and proteomics. The goals, study design, and data collection protocols are described, as well as preliminary demographic data on study participants and on diagnoses of those recruited through the California Department of Developmental Services Regional Center System.

Brief report: autistic disorder in three children with cytomegalovirus infection

Previous research has identified a relationship between autistic disorder (autism) and specific congenital infections. Three cases of congenital or perinatal cytomegalovirus (CMV) infection occurring in association with autism are described. Hypothetical mechanisms relating congenital infection, such as CMV, to the development of autism are discussed. A better understanding of the immunologic response to certain congenital infections may provide important information pertaining to the pathophysiology and etiology of autism in vulnerable individuals.

Paradoxical autonomic response to mental tasks in autism

Autonomic responses to mental tasks requiring sustained attention were examined in individuals with autism and age- and ability-matched controls. Cardiac autonomic function (CAF) was evaluated based on heart rate variability. While the control group showed a significant decrease in the parasympathetic function during mental tasks, the autistic group showed no significant changes in CAF. When examined individually, parasympathetic function was suppressed in all subjects in the control group. On the other hand, parasympathetic function was activated in half of the autistic subjects. The paradoxical autonomic response suggests that some autistic subjects were more stressed under 'resting' conditions than while performing mechanical or repetitive mental tasks. The results seem to support autonomic hyperarousal in some people with autism.

Prenatal viral infection leads to pyramidal cell atrophy and macrocephaly in adulthood: implications for genesis of autism and schizophrenia

We investigated the role of maternal exposure to human influenza virus (H1N1) in C57BL/6 mice on Day 9 of pregnancy on pyramidal and nonpyramidal cell density, pyramidal nuclear area, and overall brain size in Day 0 neonates and 14-week-old progeny and compared them to sham-infected cohorts. Pyramidal cell density increased significantly (p < 0.0038) by 170% in Day 0 infected mice vs. controls. Nonpyramidal cell density decreased by 33% in Day 0 infected progeny vs. controls albeit, nonsignificantly. Pyramidal cell nuclear size decreased significantly (p < 0.0465) by 29% in exposed newborn mice vs. controls. Fourteen-week-old exposed mice continued to show significant increases in both pyramidal and nonpyramidal cell density values vs. controls respectively (p < 0.0085 E1 (exposed group 1), p < 0.0279 E2 (exposed group 2) pyramidal cell density; p < 0.0092 E1, p < 0.0252 E2, nonpyramidal cell density). By the same token, pyramidal cell nuclear size exhibited 37-43% reductions when compared to control values; these were statistically significant vs. controls (p < 0.04 E1, p < 0.0259 E2). Brain and ventricular area measurements in adult exposed mice also showed significant increases and decreases respectively vs. controls. Ventricular brain ratios exhibited 38-50% decreases in exposed mice vs. controls. While the rate of pyramidal cell proliferation per unit area decreased from birth to adulthood in both control and exposed groups, nonpyramidal cell growth rate increased only in the exposed adult mice. These data show for the first time that prenatal exposure of pregnant mice on Day 9 of pregnancy to a sublethal intranasal administration of influenza virus has both short-term and long-lasting deleterious effects on developing brain structure in the progeny as evident by altered pyramidal and nonpyramidal cell density values; atrophy of pyramidal cells despite normal cell proliferation rate and final enlargement of brain. Moreover, abnormal corticogenesis is associated with development of abnormal behavior in the exposed adult mice.

Imitation, mirror neurons and autism

Various deficits in the cognitive functioning of people with autism have been documented in recent years but these provide only partial explanations for the condition. We focus instead on an imitative disturbance involving difficulties both in copying actions and in inhibiting more stereotyped mimicking, such as echolalia. A candidate for the neural basis of this disturbance may be found in a recently discovered class of neurons in frontal cortex, 'mirror neurons' (MNs). These neurons show activity in relation both to specific actions performed by self and matching actions performed by others, providing a potential bridge between minds. MN systems exist in primates without imitative and 'theory of mind' abilities and we suggest that in order for them to have become utilized to perform social cognitive functions, sophisticated cortical neuronal systems have evolved in which MNs function as key elements. Early developmental failures of MN systems are likely to result in a consequent cascade of developmental impairments characterised by the clinical syndrome of autism.

Classification of developmental delays

Developmental delay is frequently used to identify children with delay in meeting developmental milestones in one or more streams of development. There is no consensus on the specific definition. Developmental delay is best viewed generically as a chief complaint rather than a diagnosis. A child suspected to have delays should always be assessed in each of the major streams of development: expressive and receptive language, including social communication; visual problem solving (nonverbal cognition); motor development; neurobehavioral development; and social-emotional development. A model developed by the National Center for Medical Rehabilitation Research is used to compare existing classifications of developmental delays. This model defines the five domains in the disability process: pathophysiology, impairment, functional limitation, disability, and societal limitation. An etiology domain is added. This model is used to illustrate how existing classification systems of cerebral palsy, mental retardation, autism, and language delay draw on information from one or more domains. The model illustrates some of the conflicts between different systems. For example, most classification systems for cerebral palsy emphasize only impairment (spasticity, dyskinesias, and topography). The current definition and classification system for mental retardation focuses on functional limitations (IQ), disability, and societal limitations, ignoring pathophysiology and details of impairment. Given the complexity of neurodevelopmental disabilities, it is unlikely that a single classification system will fit all needs.

Current research findings on childhood autism

OBJECTIVE

To review the main areas of current research findings regarding the core deficits in autism and the implications of these findings for the practicing clinician.

METHOD

Behavioural, cognitive, emotional and neurophysiological aspects are covered with an emphasis on the importance of methodology.

RESULTS

The implication of these findings for the treatment of autism is discussed.

CONCLUSION

Autism can teach us how we learn about emotions and the possibility of sensitive periods of development.

Clinical review: Medical differential diagnosis and treatment of the autistic syndrome

Autism, like mental retardation, is not a definitive diagnosis. This paper discusses the medical differential diagnosis to consider when patients present with autistic symptoms. Summarizing the medical literature, the known infectious, metabolic, chromosomal and structural lesions are reviewed. Autism also can be associated with sensory handicaps, such as blindness and deafiness. When the autistic syndrome is associated with a second syndrome, this produces a "double syndrome" in the patient. A thorough medical evaluation of all individuals with autism is suggested.

Diagnostic and assessment issues related to pharmacotherapy for children and adolescents with autism

Autism involves not only developmental delays but also aberrant behavior, both of which change in nature over time. Rating instruments may be useful to assess maladaptive and adaptive behaviors of autistic children in a standardized way and, perhaps, to measure change due to treatment. With the expansion of basic science, knowledge, and technology, there is increasing evidence that autism is etiologically heterogeneous. Currently, there is no biological marker specific to autism, although hyperserotonemia is a consistent finding in one third of autistic children. An aim of basic science research has been to develop a rational pharmacotherapy based upon the underlying neurochemistry. However, at the present time, this approach has not always been successful. It is expected that the development and use of more restrictive criteria, delineation of subtypes of autism, and interaction of descriptive, behavioral, clinical, and basic research will lead to more effective planning for treatment. The relationship of assessment to treatment response is presented and discussed.

Use of differential reinforcement of low rates of behavior to decrease repetitive speech in an autistic adolescent

A differential reinforcement of low rates of behavior (DRL) schedule was successful in reducing repetitive speech in an autistic adolescent. Over a period of 18 months, the rate of repetitions was gradually reduced from a mean of 4.7 to less than 0.3 repetitions per min. Tokens were awarded for maintaining rates of repetitive speech below each of nine successive criterion levels. A reversal phase in which the token economy was no longer in effect resulted in a return to baseline repetition rates. Subsequent reintroduction of the contingencies saw a return to previous low levels of responding which were maintained at a 6-month and 14-month follow-up.

Familial autism and the fragile-X chromosome

This report presents two male siblings in whom the diagnosis of infantile autism was found in association with a fragile site on the X chromosome. In addition to their marked autistic characteristics, formal examinations indicated that both boys were severely mentally retarded and had several physical features commonly observed in association with the fragile-X syndrome. The mother of these two siblings also gave birth to identical twin boys, who were developmentally delayed and showed several autistic features prior to their untimely death in a house fire. The possible role of the fragile-X chromosome as an etiological factor in families where there is a clustering of autism and related developmental disturbances is discussed.

The influence of vigorous versus mild exercise on autistic stereotyped behaviors

A major problem encountered in many autistic children is their high rate of stereotypic behavior, which has been shown to interfere with on-task responding and other appropriate behaviors. Since the experimental literature indicates that physical exercise can positively influence both appropriate and inappropriate behaviors, including the children's stereotypic behaviors, the purpose of this study was to investigate whether the specific type of exercise (i.e., mild vs. vigorous) would differentially affect subsequent stereotyped behaviors. The results demonstrated that (1) 15 minutes of mild exercise (ball playing) had little or no influence on the children's subsequent stereotyped responding, and (2) 15 minutes of continuous and vigorous exercise (jogging) was always followed by reductions in stereotyped behaviors. These results are discussed in relation to cognitive, physiological, and educational implications.

Autism in a child with congenital cytomegalovirus infection

A case is reported of early infantile autism associated with a congenital cytomegalovirus infection. The diagnosis of autism is based on the child's failure to develop good interpersonal relationships, poor eye contact, delayed and deviant use of language, and her rote and nonthematic use of objects and playthings. Resistance to change and self-stimulatory behavior were also present. Onset was before 2 years of age. Congenital cytomegalovirus infection was suggested by the presence of an antibody response to the virus, culture of the virus from the urine, sensorineural hearing loss, and inflammatory damage to the retina of the eye. Although over time improvement was noted, at last examination at the age of 5 years her behavior is still markedly deviant. This and other reported cases suggest that congenital viral infection may be an important cause of infantile autism. It is hypothesized that an ability of the agent to establish chronic infection may predispose to behavioral aberration.

A comparison of verbal, sign, and simultaneous systems for the acquisition of receptive language by an autistic boy

The effectiveness of verbal, sign, and simultaneous systems for the acquisition of receptive language by an autistic boy was investigated. The subject received training in all three methods by three teachers on each of 18 days. The order of methods and teachers was counterbalanced daily. The study incorporated a 27-word vocabulary composed of nouns, adjectives (colors), and verbs. The dependent variable was the number of correct responses during three daily sets of 20 assessment trials. Results suggest nonsignificant differences among the three methods. A secondary purpose was to investigate systematically the concomitant increases in subject-initiated interactions and eye contact accompanying the language training. The subject was observed during 10-min rest periods following each of the three daily language sessions; the occurrence of behaviors during timed intervals served as the dependent variables. Significant increases for subject-initiated interactions involving physical contact were observed.

Genetic regulation of neurotransmitter enzymes and receptors: relationship to the inheritance of psychiatric disorders

This report begins with a summary of the evidence for genetic involvement in certain major psychiatric syndromes. The relation of these disorders to deficits in central nervous system neurotransmitters is also summarized. These reviews serve as an introduction to our studies on the genetic regulation of neurotransmitters and their enzymes and receptors in inbred mice. The steady-state levels of the adrenal catecholamine biosynthetic enzymes are controlled genetically; not only is each enzyme regulated by a single locus, but also there is statistical evidence that the phenotypic expression of the entire pathway is regulated by a single gene. Studies on the biochemical mechanism of gene action suggest that genetic regulation is exerted on proteolysis of the enzymes, rather than their synthesis. In addition, we have examined the genetic control of dopamine receptors in inbred mice. Dopaminergic receptors in the nigrostriatal and mesolimbic pathways are under genetic control. Preliminary evidence suggests that the pathways are regulated by different genetic systems. If this early speculation proves true, it would have important clinical implications.

Hemispheric asymmetries and early infantile autism

The observation that language disorders constitute a major symptom of early infantile autism has led some researchers to speculate that the autistic syndrome may be a result of brain damage to the left hemisphere. Such speculation has fostered a number of studies in which attempts have been made to link autism with ostensibly positive signs of left hemisphere damage, such as left-handedness and preferences for "right hemisphere" functional and cognitive activities. In the present review, contributions to this area are systematically reviewed. Studies attempting to demonstrate that an unusually high incidence of left-handedness occurs in autistic samples are examined. Functional and morphological studies examining patterns of asymmetry in autistic samples are reviewed. It is shown that most studies on handedness fail to account adequately for the role that age of subjects may play in the manifestation of left-handedness. A simple cause-and-effect model of abnormal cerebral asymmetry and autism is rejected in favor of a more integrative yet parsimonious model that specifically attempts to explain the language disorder common to autism.

Biochemical genetics of neurotransmitter enzymes and receptors: relationships to schizophrenia and other major psychiatric disorders

Genetic control of catecholamine biosynthetic enzymes and dopamine receptors is described. The steady-state levels of each of the catecholamine biosynthetic enzymes in the adrenal is regulated by a single genetic locus. The entire biosynthetic pathway gives the appearance of concerted inheritance under the control of a single locus. Mesolimbic and nigrostriatal dopamine receptors are also genetically regulated. Preliminary evidence suggests that agonist binding sites differ from antagonist sites in both brain regions, and that the genetic controls, which are expressed on receptor site number, are independent in the two brain regions.

Prolonged brainstem transmission time in autism

Brainstem auditory evoked potentials (BAEPs) to clicks presented monaurally were gathered for 16 institutionalized children with a prior diagnosis of autism and with no hearing loss as tested by standard audiometry. Twenty age-matched normal children served as controls. Brainstem transmission time, defined as BAEP interpeak I-V latency, was prolonged significantly on the average in the autistic sample on both left and right sides. Individually, BAEPs for 9 of the 16 autistic children (or 56%) on whom some electrophysiological data were gathered were classified as abnormal when compared to the norms established in the control group. The most common BAEP abnormality was a prolonged interpeak III-V latency on the left side.

Histidinemia and infantile autism

A 10-year-old boy first showed features of infantile autism at age 24 months. Histidinemia was also diagnosed, with histidine blood levels seven times higher than the upper normal values. If the coexistence of autism and histidinemia was not coincidental, histidinemia may have constituted a necessary but not sufficient factor leading to the clinical condition of autism. Other members of the patient's family had high blood levels of histidine, but did not show symptoms that have been related to histidinemia.

Effects of age on communication skill levels and prevalence of maladaptive behaviors in autistic and mentally retarded children

This study investigated the effect of age on communication and maladaptive behavior in autistic and mentally retarded children. Forty-seven autistic and 128 mentally retarded children in a special school served as subjects. The cross-sectional method was used to compare junior and senior groups, and ratings on communication skills and maladaptive behaviors were obtained from teachers. We found that the skills of comprehension and conversation in autistic children improved significantly with age, and speech improved somewhat. In spite of this improvement in communication skills, maladaptive behaviors in the autistic children other than hyperactivity did not change significantly with age. Withdrawal improved significantly with age in the mentally retarded children but not in the autistic children.

Speech skill levels and prevalence of maladaptive behaviors in autistic and mentally retarded children: a statistical study

Forty-seven autistic and 128 mentally retarded children, ages 6 to 14, from a special school were assessed in terms of nine maladaptive behaviors and speech skill levels. The results indicated that the group of the mentally retarded children with withdrawal had significantly lower speech skill levels than the group of those without withdrawal, and the group of the autistic children with self-injury had significantly lower speech skill levels than the group of those without self-injury.

Comprehension skill levels and prevalence of maladaptive behaviors in autistic and mentally retarded children. A statistical study

A statistical study on the comparison of the comprehension skill levels between the group with and the group without each maladaptive behavior of nine items was done for autistic and mentally retarded children. Results indicated that the group of the autistic children with hyperactivity or withdrawal had slightly, not significantly, lower comprehension skill levels than the group of those without each of these maladaptive behaviors. On the other hand, the correlation between the prevalence of hyperactivity or withdrawal and lower comprehension skill levels was seen more clearly, with statistically significant differences, rather among the mentally retarded children.

Sensorimotor functioning and communication in mute autistic children

There were two purposes underlying this study: to describe the sensorimotor functioning of mute autistic children and to relate their sensorimotor performance to nonverbal communication. Twelve mute children, diagnosed autistic, ranging from 4 years 9 months to 12 years of age, were administered four scales of sensorimotor development from the Uzgiris and Hunt (1975) series: object permanence, gestural imitation, means for obtaining environmental events, and causality. Subjects performed most poorly on the imitation scale with 9 of 12 performing below Piaget's fifth sensorimotor stage. In contrast, performance was highest on the object permanence scale: No child scored below Stage V. Regarding the subjects' non-scales and Stage III on the imitation scale appeared to form minimal prerequisites for intentional communication in a variety of situations. Finally, none of the subjects, even those with relatively complete sensorimotor development, spontaneously used what Bates (1976) has called "protodeclarative" gestures to point out or show objects to adults. The absence of protodeclarative gestures may represent a qualitatively distinct pattern of prelinguistic development in certain autistic children.

Psychotic behavior in children under the institutions for mentally retarded in Denmark

The purpose of this research project was to identify children with psychotic behavior in the Institutions for the Mentally Retarded in Denmark and to analyze psychotic behavior. The subjects for study were 392 children, partly selected as a representative sample, partly selected as a sample of children with psychotic behavior. A combined observation and interview scheme was constructed containing 17 behavioral items and 6 developmental scales. Scoring systems for psychotic behavior were constructed and their consistency analyzed by the Rasch item-analysis model. Two major behavioral dimensions, "bizarre behavior" and "psychotic withdrawal," were used for the diagnostic grouping of the subjects. The distributions of the children in regard to developmental retardation, organic brain damage, and psychiatric diagnoses were investigated. Conclusions regarding guidelines for reorganization of present services and establishment of new services are proposed.

Evidence from auditory nerve and brainstem evoked responses for an organic brain lesion in children with autistic traits

In an attempt to resolve the question as to whether children with autistic traits have an organic nervous system lesion, auditory nerve and brainstem evoked responses were recorded in a group of 15 children with autistic traits. The most obvious results included a longer response latency of the auditory nerve and a longer brainstem transmission time, compared to normal children. Five of the autistic children were found to be profoundly deaf. These results strengthen the theory that an organic lesion of the nervous system can give rise to autistic traits.

Motor development of autistic monozygotic twins: a case study

A pair of autistic monozygotic twins were assessed on relevant portions of the Geddes Psychomotor Inventory. Over-all motor development of the 3-yr., 6-mo. old twins was similar and considered a partial consequence of the same genotype and comparable environmental experiences from birth. The twins exhibited poor or unsuccessful performance on tasks requiring abilities in language, communication, and appropriate relationships to objects; superior performance on specific fine manual motor skills, walking balance board, and climbing; at-age performance on tasks which were considered measures of patterned gross movement, balance, postural maintenance, and spatial orientation; and few typical autistic motor characteristics.

A pair of classically early infantile autistic siblings

This case study describes in detail two autistic siblings who were mentioned in Rimland's analysis of checklists for psychotic children, as the only pair of classically early infantile autistic siblings (Rimland, 1971). One of the children, a nonverbal girl, now 13 years old, who developed epileptic seizures at age 41/2, shows all symptoms of early infantile autism even today. Her brother, now 24 years old, however, does not fit any of the known psychopathological patterns of childhood. The boy showed all symptoms of early infantile autism, but also some of the main characteristics of childhood schizophrenia and austic psychopathy. It is suggested that we are dealing perhaps with an unusual mixed type falling within a broad category of genetically determined types of autistic disorders.

Systematic observation of play behavior in autistic children

The play behavior, defined as interaction with peers and objects, of five autistic children was systematically observed in four environments, i.e., a stark environment, a theraplay unit, a playroom, and an outside play deck. The preliminary results suggested that (1) with some children environment has little or no effect on their play behavior; (2) with multiple objects, autistic children frequently related to the objects rather than to their peers; (3) object play was most frequently at the manipulative stage and often included repetitive and negative behavior; (4) within a confined space with no objects present, autistic children frequently engaged in solitary repetitive behavior; and (5) within a confined space designed to facilitate a movement flow (theraplay), autistic children modeled and imitated and were involved in gross motor play together.

Autism and attention: theoretical considerations and a pilot study using set reaction time

We have presented an attentional model that may have value in the pathophysiology of autism. We have presented data that suggest attentional dysfunction and an attentional hypothesis that may explain autism's multisensory clinical appearance and natural history. Only further studies will be able to evaluate this hypothesis and hopefully provide us with something more promising to offer parent and child in the way of therapy.