Psychotic-like symptoms and positive schizotypy are associated with mixed and ambiguous handedness in an adolescent community sample.

The objective of this study was to replicate the association between atypical handedness and psychosis-proneness in a representative sample of adolescents from the general population. It expands previous studies by (1) analyzing a variety of atypical handedness indexes (left, mixed, ambiguous, and inconsistent), (2) measuring comprehensively the multidimensionality of psychosis-proneness, and (3) analyzing the association of different patterns of atypical handedness with nonclinical dimensions of both trait (schizotypy) and sub-clinical symptom (psychotic-like experiences) levels. Seven hundred and twenty-eight adolescents were assessed for handedness by the 12-item self-report Annett Hand Preference Questionnaire and for psychosis-proneness by the Oxford-Liverpool Inventory of Feelings and Experiences and the Community Assessment of Psychic Experiences scales. Writing-hand alone did not detect associations between laterality and psychosis-proneness. Mixed- rather than left-handedness was related to psychosis-proneness, and this was more evident when analyzing subjects with ambiguous handedness exclusively. When analysis was restricted to subjects with non-ambiguous handedness, strong left-handedness was related to psychosis-proneness. The positive dimension showed a stronger association than the negative one with atypical handedness. Results partially support mixed-handedness as a marker of developmental disorders underlying both atypical lateralization and psychosis-proneness. Among various possible mixed-handedness patterns, inconsistent hand use across primary actions, and for the same action across time, seems particularly related to psychosis-proneness and thus requires further exploration.

Evaluación de la conducta adolescente con las Escalas de Achenbach: ¿existe concordancia entre diferentes informantes?

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Summary: Introduction Behavioural problems in adolescents are thought to be relevant as strong predictors for the detection of other psychological disorders. For this reason and due to the importance they present by themselves, carrying out an adequate assessment of them is fundamental. Mental health professionals have diverse opinions about the value and importance of the different informants. The majority choose of their sources according to the disorder and necessities of each evaluator. On the other hand, the need to obtain data about adolescents' functioning from multiple resources has been emphasised and numerous reasons have been exposed. Concretely, the fact of carrying out the most objective and complete evaluations as possible has been considered essential in those studies aimed at evaluating behavioural alteration in adolescents. For this reason, Achenbach developed three versions of his scale: one for the parents, another for the teachers and a third one for the adolescents themselves. Numerous investigations have studied the concordance between groups of informants about different behavioural alterations in adolescents, but none have carried out a complete analysis of all informants in all subscales (not only the total ones). For this reason, the current study has been developed with the aim of contributing to obtain an enriching vision for the professional in the field. Objectives. a) To systematically explore agreement patterns between adolescents, teachers and parents who inform of behavioural problems in adolescents in the general population and b) in those cases in which no agreement is found, to analyse the level of disagreement between each pair of informants for each subscale. Methodology. Cross-sectional and descriptive study Participants. The study was formed by 160 triads of parents, teachers and 13-16 year old adolescents selected from several schools in Barcelona. Instruments. The three forms of the Achenbach scale to measure behavioural alterations were applied. The scale was translated into Spanish by the Unit of Epidemiology and Diagnostic in Psychopathology of the Development of the Universidad Autónoma de Barcelona: Youth Self-Report, self-evaluated, Child Behaviour Checklist/4-18 and Teacher's Report Form, both heteroevaluated and completed by parents and teachers, respectively. These three forms contain a 89-item set that evaluates the same behaviour, where eight items are organised in scales of syndromes derived empirically and which are invariant throughout informants. The eight subscales are: withdrawn, somatic complaints, anxious/depressed, social problems, thought problems, attention problems, delinquent behaviour and aggressive behaviour. Some of them are grouped in second order factors: the first three in internalising, the last two in externalising, and the rest of them provide a total problems punctuation. Statistical procedure. Agreement values were analysed for each pair of informants and each subscale through the Intraclass Correlation Coefficient (ICC). A value below 0.40 indicates low concordance. In these cases, the statistical analysis proceeds with the discordance analysis by pairs of informants and for each subscale through the Bland Altman Method. Results. A low concordance (below 0.40) between informants was found especially in internalizing scales (0.230). A slightly higher value was found in attention (0.334), aggressive behaviour (0.371), externalizing (0.357), and total subscales (0.327). Secondly, it was observed that, when informing about somatic complains, thought and attention problems, internalising items and the total scale, parents reported more alterations, followed by adolescents and teachers. Also, parents indicated more withdrawal problems in adolescents, although in this case they were followed by teachers and adolescents themselves. Finally, in the evaluation of the anxiety/depression scales, social problems, delinquent behaviour, aggressiveness and externalising conducts, adolescents informed of more alterations followed by their parents, and then by the teachers. Regarding the agreement/disagreement variability throughout the scales scores, the discordance between different informants was higher when the punctuation was further away from normality, generally when the scales were scored higher. Discussion. The normative criteria of comparison and the reference frames for each group of informants are different. For instance, the fact that teachers report less behavioural alterations could be explained because of their familiarity in dealing with adolescents and a higher tolerance towards some behaviors. In general terms, this result fits in with most conclusions from investigations carried out in this field. On the other hand, the fact that parents inform of more internalising problems could be attributed to adolescent behaviour which would in turn alter the family context. Another explanation might be that parents are on the whole more implicated and more sensitive in detecting certain conducts or behavioural alterations in their offspring. In any case, it is disputable whether the lack of concordance between the different informants does really exist or, on the contrary, adolescent behaviour changes depending on the context. Finally, a result contradicting those found in the studies reviewed is that adolescents are the ones who report more externalising problems. Other authors have found that adolescents inform more about internalising problems, something which should be expected taking into account that they are the ones who know themselves better. This could be possibly explained by the presence of more social desirability/undesirability among the adolescents of our sample in front of their pair group when answering to the evaluation scales; this may be due to the group context in which the case was applied. The main limitation of the present study that it was carried out with a general population sample, although from another point of view this may be considered as a gain of the study. We recommend carrying out explicative studies about discordance, which could clarify the predictive validity of each informant group and make variations in the type of sample under study. Conclusions. Data from different sources contribute with specific information of relative validity. This is why a multidimensional, multisituational and mulitiinformant approach is fundamental. This is necessary not only to evaluate behavioural alterations in adolescents within a research context, but also when taking diagnostic decisions in a clinical context, because, depending on the chosen informant, the diagnostic criteria for one disorder or another might change. Also, our results imply that there may be an underdetection of behavioural problems in adolescents by the adults, which would result in a lower psychological demand than the necessary.

¿Explica la esquizotipia la discordancia entre informantes de alteraciones conductuales adolescentes?

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Summary: Introduction. Behavioural alterations are a quite potent predictor for schizophrenia. Very often, apparently healthy adolescents (who will later develop schizophrenia) present altered conducts similar to those manifested by schizophrenic subjects and as predictors for the disorder. There are studies that describe the relationship between these behavioural alterations and the features found in schizotypical personality disorder or schizophrenic symptoms. In this way, it has been established that those subjects who obtain high scores in schizotypy present more behavioural alterations. Concretely, the different behavioural alterations have been differentially related to the positive and negative subtypes of the schizotypical personality, suggesting continuity between the nature of premorbid conducts and the adult symptoms patterns in which the illness develops. On the other hand, comparing adolescents that will later develop schizophrenia with those who will not, it has been found that the best schizophrenia predictor is a poor behavioural adjustment. Moreover, if the teachers' reports are examined, there can be certain aspects such as the early behavioural patterns which will identify children who, for instance, will develop schizophrenia thirty years later, or even differential patterns according to the gender of the subjects. Therefore, if we want to carry out a schizophrenia prediction according to these behavioural criteria, knowing which informants are more useful and how their opinions match among them is of a great interest. Until this moment, the majority of studies have pointed out at the ability of teachers to identify conducts that can be used to select people at risk for schizophrenia. However, having into account that numerous studies conclude that there is a lack of agreement between these and other different informants for behavioural alterations in adolescents, the importance of studying the variables that can be influencing this matter must be raised. Following with the line of our research group a question is raised. We wonder if the presence of schizotypical personality traits makes the adolescents behaviour more ambiguous, with the consequent difficulty to define it in a coincident way from different evaluators and from themselves. Objectives. To analyse the influence of the schizotypical personality (assessed with the Oxford-Liverpool Inventory of Feelings and Experiences), the demographic variable gender and the interaction between them, in the discordance of different informants (parents, teachers and adolescents) when they inform about behavioural problems in adolescents (assessed with the Achenbach's scales). Methodology. This is an analytic transversal study that can be framed into a longitudinal study of 2 cohorts from the general population, which started on 2000 and has been then followed-up ("Psychoeducation program and early detection of schizophrenic disorders of adolescent onset"). Participants. 160 triads of parents, teachers and adolescents from 13 to 16 years old selected from 7 schools of Barcelona took part in the study. Instruments. The three forms of the Achenbach scale for the measure of behavioural alterations were applied: Youth Self- Report, Child Behaviour Checklist/4-18 and Teacher's Report Form. These forms contain 8 scales which are invariant throughout informants: Withdrawn, somatic complaints, anxious/depressed, social problems, thought problems, attention problems, delinquent behaviour and aggressive behaviour. Some of them are grouped in second order factors: Internalizing, externalizing and total. To evaluate the psychometrical schizotypical personality of adolescents we used the Oxford-Liverpool Inventory for Feelings and Experiences. It consists of an autoadministered inventory with 159 items that includes four schizotypical scales. The Unusual Experiences scale reflects the positive dimension of schizotypy and includes items of unusual perception aberrations and magical thinking. The Introvert Anhedonia Scale reflects the negative dimension of schizotypy and consists of items assessing restricted affect, social isolation and anhedonia. The Cognitive Disorganization Scale refers to disorganized aspects of the psychosis and it is composed of items assessing difficulties in concentration and decision-making. Finally, the Impulsive Nonconformity Scale reflects the characteristics of impulsive-type personality, social anxiety and maladjusted behaviours. Statistical proceed. Multiple regression analyses were carried out in order to revise the influence of the schizotypical personality, the demographic variable gender and the interaction between them as possible explicative variables, in the discordance between different informants about behavioural problems of adolescents. The dependent variable was a measure of the level of discordance between the three groups of informants. Results. A major discordance between informants of behavioural problems was found as schizotypy was higher. Concretely, a larger number of unusual experiences in adolescents increase the discordance for thought and internalizing problems. Discordance is also higher in aggressiveness and anxiety/depression as cognitive disorganization increases. Also, the higher the introverted anhedonia, the higher the discordance is for social problems, anxiety/depression, attention, externalizing problems, and for the total. To finish, a high score in non-conformity impulsivity increases the discordance for attention, delinquency and aggressive problems. About the influence of gender, discordance between informants for anxiety/depression is higher for females than for males. However, this varies when the interaction effects found are considered. In this way, a differential effect for the increase of non-conformity impulsivity and introvert anhedonia can be observed in males and females. Therefore, discordance between informants is higher when evaluating anxiety/ depression in males when non-conformity impulsivity is high. Just the opposite happens for girls. In addition, the discordance for the internalizing subscale increases just as the introverted anhedonia raises for females, but it decreases when evaluating males. Discussion. It seems clear that no source of data can be substituted for any other when evaluating behavioural problems in adolescents and much less when attention is centred in those adolescents who score high in schizotypy. Specifically, when evaluating the behaviour of those subjects who score high in the positive dimension of schizotypy, the agreement between informants decreases for thought and internalizing problems; and, when the behaviour of those who are defined for a more negative schizotypy is evaluated, the agreement decreases for social problems, anxiety/ depression, externalizing and total. Having all this into account and adding information that other authors have found related to each schizotypy subtype (which, besides, are the ones which more concordance show), some conclusions could be raised. It can be assumed as evident that schizotypical personality (and each trait type) and the subjacent conduct in these subjects can generate a difficulty in perceiving certain conducts which are not predominant in the subject, with the consequent discordance between informants. For future studies, it would be very interesting to carry out studies examined which group of informants augurs the behavioural predisposition for schizophrenia and its dimensions in the most accurately way possible. Conclusions. A most exact and objective method to assess behavioural problems as well-demonstrated predictor to schizophrenia, is necessary in order to select vulnerable teenagers to the illness and to develop programs of early intervention.

Esquizotipia y memoria verbal en población general adolescente / Squizotypy and verbal memory in the adolescent general population

El siguiente trabajo analiza la relación existente entre el déficit de memoria verbal y los rasgos de esquizotipia psicométrica en una población no clínica de sujetos adolescentes. En este estudio transversal analítico participaron 139 estudiantes de Secundaria con edades comprendidas entres los 13 y los 16 años (media= 14,35; Des.Est.= 0,548). Tras pasar las pruebas O-LIFE (esquizotipia psicométrica), TAVEC (memoria verbal) y Subtest del WAIS-III de letras y números (memoria de trabajo), se analizaron los datos realizando correlaciones de Pearson y comparaciones de medias. Los resultados mostraron una ausencia de relación entre las medidas de esquizotipia y memoria de trabajo. En cambio, sí encontramos relaciones significativas entre las dimensiones de esquizotipia y memoria verbal. Nuestros resultados apoyan parcialmente la literatura revisada sobre este tema. Aun así, se sugiere profundizar en el estudio de la esquizotipia psicométrica como marcador de riesgo para la esquizofrenia

The following study examines the relationship between verbal memory deficits and schizotypal traits measured psychometrically from a non- clinical adolescent population. In this transversal analytical study participated 139 subjects. They were secondary school students, with ages ranging from 13 to 16 years old (mean= 14, 35; Sta.Dev.= 0, 548). After administrating the scales O-LIFE (psychometrical schizotypy), CVLT (verbal memory), and Letters and Numbers subtest of WAIS-III (working memory), data was analyzed utilizing Pearson correlations and mean comparison test. Results showed lack of relations between schizotypy measures and working memory. Nonetheless, some of the O-LIFE dimensions correlated with verbal memory. These findings support partly the literature reviewed. Yet, more work focused on schizotypy and cognitive deficits as risk factors are suggested

[Schizotypy and verbal memory in the adolescent general population]. / Esquizotipia y memoria verbal en población general adolescente.

The following study examines the relationship between verbal memory deficits and schizotypal traits measured psychometrically from a non- clinical adolescent population. In this transversal analytical study participated 139 subjects. They were secondary school students, with ages ranging from 13 to 16 years old (mean= 14, 35; Sta.Dev.= 0, 548). After administrating the scales O-LIFE (psychometrical schizotypy), CVLT (verbal memory), and Letters and Numbers subtest of WAIS-III (working memory), data was analyzed utilizing Pearson correlations and mean comparison test. Results showed lack of relations between schizotypy measures and working memory. Nonetheless, some of the O-LIFE dimensions correlated with verbal memory. These findings support partly the literature reviewed. Yet, more work focused on schizotypy and cognitive deficits as risk factors are suggested.