A taxometric analysis of cognitive and neuromotor variables in children at risk for schizophrenia.

A taxometric model was applied to detect a subgroup or taxon of children conjectured to be at highest risk for developing schizophrenia or related disorders in a sample of offspring of schizophrenic, depressed, and normal parents. Measures of cognitive and neuromotor performance in childhood were used as indicator tests in the analyses. A taxon consisting chiefly of children of schizophrenic parents was detected. Forty-seven percent of those children were assigned to the taxon, compared with 16% of the children of depressed parents and 4% of the children of normal parents. Assignment to the taxon is assessed in relation to the current functional status of the subjects in young adulthood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Schizophrenia: Effects of inheritance and rearing on reaction time.

Studied both manual and verbal reaction time in 4 selected groups of adult Ss (N = 258) in an attempt to uncover hereditary and environmental influences on the reaction time of Ss whose parents do or do not have schizophrenic disorders. The groups included (a) adoptive offspring of schizophrenic parents (adoptive index); (b) adoptive offspring of nonschizophrenic parents, but whose adoptive parents had a psychiatric record of schizophrenic disorder (cross-foster); (c) adoptive offspring of nonschizophrenic parents (adoptive control); and (d) offspring of schizophrenic parents who were reared by their biological parents (nonadoptees). Analysis of variance was used to assess the effects of rearing by a schizophrenic parent, a genetic background for schizophrenia, and interaction between rearing and genetic background. Groups opposed for genetic background for schizophrenia were not different in reaction time performance, while groups opposed for rearing by a schizophrenic parent were significantly so. Mean reaction time was slower in groups reared by a schizophrenic parent than in those reared by a nonschizophrenic parent. There was no significant interaction between rearing and genetic background for reaction time performance. (French summary) (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Global attentional deviance as a marker of risk for schizophrenia: Specificity and predictive validity.

Evaluated global attentional deficits as possible childhood markers of schizophrenia. Performance deviance was assessed across a continuous performance test, an attention span task, and the Digit Span subtest of the Wechsler Intelligence Scale for Children (WISC). 63 children of schizophrenic parents, 43 children of parents with affective disorders, and 100 children of normal parents were tested when the children were 7–12 yrs old. A subgroup of Ss at risk for schizophrenia displayed extreme global deviance across attentional measures. Only a small number of Ss at risk for affective disorders and normal comparison Ss showed similar extreme attentional deficits. The global attentional deficits measured at these early ages were related to behavioral disturbances (behavior was assessed in 3–6 mo intervals since 1971) in young adulthood for Ss at risk for schizophrenia, but not for Ss in the affective risk group or in the normal comparison group. It is concluded that global attentional deficits have considerable specificity for predicting behavioral problems thought to be precursors of schizophrenia or schizophrenia-related disorders. (54 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Registered criminality in families with children at high risk for schizophrenia.

Describes a project in which 207 Danish children (mean age 15.1 yrs in 1962) with schizophrenic mothers have been periodically assessed and followed since 1962. 104 children matched in age, whose parents and grandparents had never been psychiatrically hospitalized, served as controls. The number of registered criminal offenses in the Ss, their schizophrenic mothers, and their fathers was found to be higher than for controls. Implications for high-risk research and hypotheses on the relation of schizophrenia and criminality are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Schizophrenia in high-risk subjects: Prognostic maternal characteristics.

A Danish prospective, longitudinal study of 207 children (average age 15 yrs) at high risk for schizophrenia (they have schizophrenic mothers), begun in 1962, involved assessment of mothers on a number of variables. In 1972 it was found that 17 of the children of these mothers became schizophrenic. The present study sought to identify predictors of schizophrenia among antecedent maternal variables. The mothers (15 Ss) of the children who became schizophrenic (a) had psychosis precipitated by childbirth and (b) exhibited instability in their relations with men as well as antisocial behaviors. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Genetic theories and the validation of psychiatric diagnoses: Implications for the study of children of schizophrenics.

Argues that the success of prospective methods for studying the development of schizophrenia in those few offspring of schizophrenics who also become schizophrenic (high-risk method) depends on using valid diagnostic criteria for selecting the parent probands. Data from a high-risk study in which the affected parents were diagnosed by 5 clinicians are used to illustrate how different diagnostic standards affect the comparison of high-risk samples and control samples of children of other psychiatric patients. Publicly reporting careful assessments of affected parents will also facilitate comparisons among different high-risk samples and will allow estimates of the risks for individuals within each high-risk sample. Genetic theory and empirical data suggest that children with severely affected parents and children with many affected relatives will have the highest risks, while samples of children with only 1 mildly affected parent may have risks that approach the population base rates. Genetic theory further suggests that some children of validly diagnosed schizophrenics will have no genetic risk for schizophrenia, and some of those who do have the genetic predisposition will enjoy a lifetime of adequate mental health even without intervention, thus confounding the effort of high-risk research to validate indicators of the high-risk genotype with follow-up status. High-risk researchers are cautioned against premature implementation of intervention strategies based on unvalidated indicators of the risks to individuals. (2? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Negative metabolic effects of cyclic GMP in quiescent cardiomyocytes are not related to L-type calcium channel activity

Evidence of immune system abnormalities in adult schizophrenia has prompted examination of the human leukocyte antigen (HLA) system. Childhood onset schizophrenia offers a unique opportunity to test neurodevelopmental hypotheses of schizophrenia, including those which implicate components of the immune system. In the present study, class I and II HLA antigens were typed using sequence-specific primers and the polymerase chain reaction in 28 childhood onset schizophrenics and 51 ethnically matched healthy subjects. Groups were compared for frequencies of HLA antigens reported to be associated with schizophrenia and/or autoimmune disorders. We hypothesized that antigen frequencies would differ between schizophrenic and healthy children, suggesting that some dimension of the neurodevelopmental disturbance experienced by these children may be mediated by subtle abnormalities of immune function. There were no significant differences between schizophrenic and healthy subjects in the frequency of any antigen tested. These findings do not support HLA-associated pathology in childhood onset schizophrenia.     

An attentional assessment of foster children at risk for schizophrenia.

Investigated whether processes observed in adult schizophrenics could be detected in children who were not schizophrenic but were at heightened risk for the disorder. A battery of 8 attention-demanding tasks was administered to (a) 9 foster children at heightened risk for schizophrenia by virtue of having a schizophrenic biological mother, (b) 10 foster children without a family history of psychiatric disorder, and (c) 10 children living with their biological parents, none of whom had a history of psychiatric disorder. The tasks included in the battery had been demonstrated in previous research to be sensitive discriminators of adult schizophrenic pathology. Results indicate the presence of attentional dysfunction in high-risk children prior to the onset of clinical symptoms. The high-risk group showed significantly lower levels of performance on certain tasks, notably the complex versions of the span-of-apprehension and Spokes tests from the Halstead-Reitan Test Battery, and the simple conditions of the concept attainment task. Examination of low-scoring Ss, intercorrelations between tasks, and the results of a cluster analysis revealed that within the high-risk group there was a subset of Ss who showed impairment across these tasks to produce the overall low group means. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social, emotional, and intellectual behavior at school among children at high risk for schizophrenia.

Four classroom teachers rated the school behavior of 44 12–17 yr olds of schizophrenic parents and 70 Ss of normal parents as part of an ongoing high-risk study. The ratings were made by teachers using the Pupil Rating Form and the Hahnemann High School Behavior Rating Scale. Ss of schizophrenic parents showed greater interpersonal disharmony, less scholastic motivation, more emotional instability, and lower intelligence than the control Ss, but the difference in introversion was not significant. Two of the 4 Ss with 2 schizophrenic parents had extremely low ratings for scholastic motivation, harmony, emotional stability, and intelligence and a 3rd was rated extremely low on emotional stability, but none of them was extremely introverted. On the basis of the results and a preliminary examination of intermediate outcomes (early hospitalization or psychological treatment after the initial school assessments), it is concluded that disharmony, emotional instability, and low intelligence are the early markers for vulnerability to schizophrenia worthy of most attention. The surprising absence of introverted behavior among Ss of schizophrenic parents indicates that introversion—when it is observed—may best be construed not as a static typology of preschizophrenic character but as a dynamic phase in a process of coping and retreat that precedes schizophrenic breakdown, sometimes by many years. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychological evaluation of clinical disturbance in children at risk for psychopathology.

Evaluated children of 1 schizophrenic or 1 manic-depressive parent for clinical disturbance in the St. Louis risk research project between 1967 and 1971. The investigation employed a psychological battery using the WISC or WAIS, figure drawings, the TAT, the Rorschach, and the Beery-Buktenica Developmental Form Sequence, plus blind clinical disturbance ratings from the test batteries. Tests were administered individually to 339 6–20 yr old children from intact families with 1 schizophrenic, manic-depressive, or physically ill parent, or 2 normal parents. Children of psychiatrically ill parents were found to be more disturbed than children of nonpsychotic parents. Children with a schizophrenic parent demonstrated peformance on psychometric evaluation that was in some ways continuous with that of adult schizophrenics. Children of schizophrenic and manic-depressive parents differed from one another and from controls on 2 measures. In the aggressive content of their TAT stories, children with a schizophrenic parent showed less aggression than normals, and children with a manic-depressive parent showed more aggression than normals. On the Rorschach, children of schizophrenics gave more primitive responses than children of manic-depressives, and the children of normal parents gave an intermediate number of such responses. (2 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Signal detection in vigilance tasks and behavioral attributes among offspring of schizophrenic mothers and among hyperactive children.

24 children of schizophrenic mothers, 20 children of mothers with nonpsychotic psychiatric disorders falling outside the schizophrenia spectrum, and 14 hyperactive children were examined relative to groups of individually matched comparison children and to a representatively stratified group of 67 normal children. Ss were 9–16 yrs of age. Children of schizophrenic mothers showed lower mean perceptual sensitivity (PS) than matched and stratified normal children and included an excessive number of extremely poor scorers. Neither children of mothers with nonpsychotic disorders outside the schizophrenia spectrum nor hyperactive children displayed a significant deficit in PS. Hyperactive children scored lower on a beta response criterion factor across vigilance tasks and were rated as higher on an Emotionality factor and lower on a Fearful Inhibition factor than their normal peers. The perceptual sensitivity deficit among children of schizophrenic mothers was found across motivational feedback conditions and was evident throughout the vigilance period. (3? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Communication deviance in families of schizophrenic and manic patients.

Levels of communication deviance (CD) distinguish parents of schizophrenic patients from parents of nonpsychotic patients, but the prevalence of intrafamilial CD in other psychotic disorders has not been examined. Levels of CD were compared across biological parents of schizophrenic (n?=?39) and bipolar manic (n?=?16) patients and across patients themselves. CD ratings were based on Thematic Apperception Test (TAT) protocols (parents only) and family interactions (parents and patients). Total levels of CD did not distinguish between groups of parents or patients. However, instances of odd word usage were more frequent among parents of manic patients than among parents of schizophrenic patients on both CD measures. Also, during the interaction task, odd word usage was more frequent among manic patients, whereas schizophrenic patients made more ambiguous references. Results suggest that high levels of intrafamilial CD are not unique to schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Initiation and supervisory processes in schizophrenia and depression

Clinical studies show that schizophrenic and depressive subjects have problems with daily life activities, and neuropsychological studies tend to explain these problems in terms of a dysexecutive syndrome. Verbal fluency and sentence arrangement are tasks considered to focus on two aspects of the dysexecutive syndrome known as initiation and supervision processes, respectively. In this study, we assessed performance in these two tasks in schizophrenia and depression. Twenty-six schizophrenic subjects (chronic schizophrenia, DSM IV definition) were compared with 26 control subjects balanced for sex, age and educational level, and 16 depressive subjects (major depression episode, DSM IV) were compared with 11 similarly balanced control subjects. Switching and clustering scores were evaluated during a semantic fluency task as two components underlying the initiation and organization processes. Capture errors specific to failure of the supervisory system and differences between the number of correct responses in two conditions (valid/invalid) were evaluated as indexes of the supervision process in a sentence arrangement task. In the semantic fluency task, switching scores were significantly lower in the schizophrenic and depressive subjects than in their respective controls. In the sentence arrangement task, only the schizophrenic subjects made significantly more capture errors than their controls and had significantly fewer correct sequences in invalid conditions than in valid conditions. This study shows a dissociation between supervision and initiation processes in two different psychiatric populations. Initiation is impaired, but supervision is preserved in depression, whereas both initiation and supervision are impaired in schizophrenia.     

Schizophrenia and nicotinic receptors

Patients with schizophrenia often cannot respond to important features of their environment and filter out irrelevant stimuli. This dysfunction could be related to an underlying defect in inhibition--i.e., the brain's ability to alter its sensitivity to repeated stimuli. One of the neuronal mechanisms responsible for such inhibitory gating involves the activation of cholinergic nicotinic receptors in the hippocampus. These receptors are diminished in many specimens of hippocampal brain tissue obtained postmortem from schizophrenic patients. In living schizophrenic patients, stimulation of cholinergic receptors by nicotine transiently restores inhibitory gating of evoked responses to sensory stimuli. Many people with schizophrenia are heavy smokers, but the properties of the nicotinic receptor favor only short-term activation, which may explain why cigarette smoking is only a transient symptomatic remedy. This paper reviews the clinical phenomenology of inhibitory gating deficits in people with schizophrenia, the neurobiology of such gating mechanisms, and the evidence that some individuals with the disorder may have a heritable deficit in the nicotinic cholinergic receptors involved in this neurobiological function. Inhibitory gating deficits are only partly normalized by neuroleptic drugs and are thus a target for new therapeutic strategies for schizophrenia.     

Anxiety level of schizophrenic and control patients and their parents.

Rated 24 good and 24 poor male schizophrenic patients, 24 nonschizophrenic male psychiatric patients, and the parents of each for anxiety prior to and during a difficult family interaction. 2 techniques to measure anxiety on the basis of speech were employed. Some results, such as that the poor schizophrenics were the most anxious of the patients, are consistent with general beliefs and prior research. However, most results present a picture of the schizophrenic patient and his parents that is dramatically different from what most theories and research suggest. Parents did not appear to be upsetting to the patient, even when their behavior was very noxious. If the family plays a role in schizophrenia, findings suggest this role is quite different from what is widely believed. (33 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conversational repair in schizophrenic and normal children

OBJECTIVE: Children acquire the skills to monitor the adequacy of their spoken message and to self-initiate repair strategies that modify the message during early, middle, and late childhood. To characterize further the communication deficits of childhood-onset schizophrenia, this study compared self-initiated repair strategies in schizophrenic and normal children and their relationship with formal thought disorder, discourse deficits, and distractibility. METHOD: Measures of self-initiated repair, formal thought disorder, and cohesion were coded in 32 schizophrenic and 47 normal children, aged 5.6 to 12.4 years, from speech samples elicited with the Story Game. RESULTS: The schizophrenic children used some repair strategies (false starts, fillers, referential revision) more infrequently than the normal children. Within the schizophrenic group, the children who were receiving neuroleptic medication underutilized repair and had more discourse deficits than the unmedicated patients. Loose associations and distractibility were associated with increased use of false starts but not fillers. CONCLUSIONS: In addition to formal thought disorder and discourse deficits, schizophrenic children underutilize self-initiated repair when presenting their thoughts to the listener, particularly if they are being treated with neuroleptics, a potential sign of increased clinical morbidity. Impoverished communication skills might reflect negative signs in childhood-onset schizophrenia.     

Regression and disorders of thought.

Utilizing 2 tests (see 35: 5236; 36: 4JQ14C) devised to assess use of various kinds of words, the responses of elementary school children were compared with the responses of a previously obtained sample of schizophrenics. The purpose of the comparison was to test the assumption that schizophrenia involves a regression to a more primitive, infantile stage, and that the thinking of the schizophrenic would resemble that of the child. On some of the tasks, the thinking of the children and the schizophrenic were similar; on others, the children and the organics were similar. The literal use of the term regression re: schizophrenia was rejected. Methodological problems of research in this area are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Slow-wave sleep and symptomatology in schizophrenia and related psychotic disorders

Deficits in slow-wave sleep (SWS), or delta sleep, are frequently seen in schizophrenia, but their relationship with schizophrenic symptomatology remains unclear. We examined the association between visually scored and automated measures of SWS and positive and negative symptoms in a series of unmedicated patients with schizophrenia and related psychotic disorders. Total and average automated delta wave counts were significantly inversely associated with negative symptoms overall, and the psychomotor poverty syndrome in particular. Total delta counts were also inversely related to the disorganization syndrome. No relation was seen between reality distortion or the Brief Psychiatric Rating Scale (BPRS) positive symptoms and SWS. These findings support the view that SWS deficits may be related to negative symptoms of schizophrenia and may perhaps be mediated by impaired functioning of frontothalamic neural circuits.     

Residual performance deficit in clinically remitted schizophrenics: A marker of schizophrenia?

The study of remitted schizophrenic outpatients is proposed as a way of minimizing the effects of the "nuisance variables" that confound the study of hospitalized schizophrenics. 20 hospitalized acutely disturbed schizophrenics (mean age, 37.0 yrs), 20 schizophrenic outpatients in clinical remission (mean age, 42.8 yrs) and 20 normal controls (mean age, 35.1 yrs) were administered a span of apprehension test and the Continuous Performance Test (CPT). All Ss were controlled for sex and WAIS scores and schizophrenics were rated with Phillips Prognostic Rating Scale. On the CPT, both acute and remitted schizophrenics made significantly more errors of omission and commission than did the normal controls. On the span of apprehension, both groups of schizophrenics showed a significantly greater decrement in accuracy of detection of the target stimuli than did normal controls. The same pattern of results has been observed in children at risk for schizophrenia, which suggests that the span of apprehension may be sensitive to core schizophrenic processes that are independent of clinical state. The cross-sectional study of the 3 stages of schizophrenia—the premorbid, acute, and remitted—is proposed as a way of identifying "core" schizophrenic processes and markers of vulnerability to schizophrenia. The adequacy of a general "attentional impairment" interpretation of schizophrenic deficit is questioned. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hereditary increase of plasma histidine-rich glycoprotein associated with abnormal heparin binding (HRG Eindhoven)

Plasma histidine-rich glycoprotein (HRG) was found to be persistently increased in a patient with a history of recurrent arterial thromboembolic events. The mean concentration was 270% of normal pooled plasma. Increased HRG was found in eight of the 17 relatives studied, but none of them has experienced thrombo-embolism yet. Apparently, increased HRG was hereditary with autosomal dominant inheritance. A significant correlation was found between the increased plasma concentration of the protein and the age of the subjects (P < 0.02), whereas no such relation is present in a normal population. The plasma HRG of the proposita and 9 of her family members displayed abnormal binding to heparin, as assessed in a crossed affinity immuno-electrophoresis system: the usual increase in mobility after binding to heparin was absent. The binding of this variant HRG to plasminogen was normal. This case represents the first abnormal HRG variant reported and it is proposed to designate it: HRG Eindhoven.