Genetics of developmental dyslexia

Developmental dyslexia is a highly heritable disorder with a prevalence of at least 5% in school-aged children. Linkage studies have identified numerous loci throughout the genome that are likely to harbour candidate dyslexia susceptibility genes. Association studies and the refinement of chromosomal translocation break points in individuals with dyslexia have resulted in the discovery of candidate genes at some of these loci. A key function of many of these genes is their involvement in neuronal migration. This complements anatomical abnormalities discovered in dyslexic brains, such as ectopias, that may be the result of irregular neuronal migration

Family, friends, and feelings: the role of relationships to parents and peers and alexithymia in adolescents with anorexia nervosa

Background Anorexia nervosa (AN) is associated with impairments in socio-emotional functioning, including difficulties in interpersonal relationships as well as alexithymia (difficulties identifying and describing one’s emotions). Although the onset of the disorder is mostly in adolescence, a developmental period in which interpersonal relationships to parents as well as peers undergo major changes, only few studies have investigated the quality of interpersonal relationships in adolescent AN patients. Furthermore, the mechanisms linking poor relationship quality to eating disorder psychopathology are not yet clarified, albeit some research suggests that alexithymia might play a pivotal role. The aims of the present study were investigating the quality of interpersonal relationships to parents and peers in adolescents with AN compared to healthy adolescents as well as exploring the mediating role of alexithymia in the association between relationship quality and eating disorder symptoms. Methods Self-report questionnaires were used to assess relationship quality (Inventory of Parent and Peer Attachment) and alexithymia (Toronto Alexithymia Scale) in 12–18 year old female adolescents with AN (n = 35) in comparison to healthy adolescents (n = 40). Results Adolescents with AN reported lower relationship quality to both of their parents and to peers compared to healthy controls. Relationship quality scores were negatively correlated to alexithymia as well as eating disorder symptoms. Alexithymia fully meditated the association between eating disorder symptoms and relationship quality to parents and partially mediated the association between eating disorder symptoms and relationship quality to peers. Conclusion The results indicate difficulties in interpersonal relationships among adolescents with AN and emphasize the role of peer relationships for adolescents’ eating disorder psychopathology. Alexithymia seems to play an important role in explaining the link between quality of relationships and eating disorder psychopathology. Results suggest that treatment should not only focus on family relationships but also address relationships to peers as well as adolescents’ competence in identifying and dealing with their emotions

Evaluation of an online version of the CFT 20-R in third and fourth grade children

There is growing demand for digital intelligence testing. In the current study, we evaluated the validity of an online version of the revised German Culture Fair Intelligence Test (CFT 20-R). A total of 4100 children from the third and fourth grades completed the online version using a smartphone or tablet. Subsequently, 220 of these children also completed the paper-pencil (PP) version. The internal consistency and construct validity of the online version appeared to be acceptable. The correlation between the raw scores and school grades in German and mathematics was slightly lower than expected. On average, the raw scores for the PP version were revealed to be higher, which was probably due to a learning effect. At the item level, the results show small differences for the subtests Series and Matrices, possibly caused by small differences in the presentation of the items. The correspondence between the versions did not depend on children’s levels of impulsivity or intelligence. Altogether, the results support the hypothesis that the online version of the CFT 20-R is a valid measure of general fluid intelligence and highlight the need for separate norms. (DIPF/Orig.

The KOALA-study: study protocol for a comprehensive study of cognitive biases in adolescent anorexia nervosa patients compared to healthy and clinical controls

BACKGROUND Anorexia nervosa (AN) is characterized by dysfunctional cognitions including cognitive biases at various levels of information processing. However, less is known about the specificity of these biases, i.e., if they occur for eating-disorder-related information alone or also for non-eating-disorder-related emotional information in AN patients (content-specificity) and if they are unique to individuals with AN or are also shown by individuals with other mental disorders (disorder-specificity). METHODS The present study systematically assesses cognitive biases in 12-18-year-old female adolescents with AN on three levels of information processing (attention, interpretation, and memory) and with regard to two types of information content (eating-disorder-related, i.e., stimuli related to body weight and shape, and non-eating-disorder-related). To address not only content- but also disorder-specificity, adolescents with AN will be compared not only to a healthy control group but also to a clinical control group (adolescents with major depression or particular anxiety disorders). Cognitive biases are assessed within a single experimental paradigm based on the Scrambled Sentences Task. During the task eye movements are recorded in order to assess attention biases while interpretation biases are derived from the behavioural outcome. An incidental free recall test afterwards assesses memory biases. We expect adolescents with AN to show more pronounced negative cognitive biases on all three levels of information processing and for both types of content compared to healthy adolescents. In addition, we expect the specificity of biases to translate into differential results for the two types of content: AN patients are expected to show stronger biases for disorder-related stimuli but similar or less pronounced biases for non-disorder-related stimuli compared to the clinical control group. DISCUSSION This is the first study to comprehensively assess cognitive biases in adolescents with AN. It will have essential implications not only for cognitive-behavioural models of AN but also for subsequent studies aiming to modify cognitive biases in this population, thereby addressing important maintaining factors already at an early stage of the disorder

Evidence for the late MMN as a neurophysiological endophenotype for dyslexia.

Dyslexia affects 5-10% of school-aged children and is therefore one of the most common learning disorders. Research on auditory event related potentials (AERP), particularly the mismatch negativity (MMN) component, has revealed anomalies in individuals with dyslexia to speech stimuli. Furthermore, candidate genes for this disorder were found through molecular genetic studies. A current challenge for dyslexia research is to understand the interaction between molecular genetics and brain function, and to promote the identification of relevant endophenotypes for dyslexia. The present study examines MMN, a neurophysiological correlate of speech perception, and its potential as an endophenotype for dyslexia in three groups of children. The first group of children was clinically diagnosed with dyslexia, whereas the second group of children was comprised of their siblings who had average reading and spelling skills and were therefore "unaffected" despite having a genetic risk for dyslexia. The third group consisted of control children who were not related to the other groups and were also unaffected. In total, 225 children were included in the study. All children showed clear MMN activity to/da/-/ba/contrasts that could be separated into three distinct MMN components. Whilst the first two MMN components did not differentiate the groups, the late MMN component (300-700 ms) revealed significant group differences. The mean area of the late MMN was attenuated in both the dyslexic children and their unaffected siblings in comparison to the control children. This finding is indicative of analogous alterations of neurophysiological processes in children with dyslexia and those with a genetic risk for dyslexia, without a manifestation of the disorder. The present results therefore further suggest that the late MMN might be a potential endophenotype for dyslexia

Entwicklungsstörungen schulischer Fertigkeiten

Der Beitrag gibt einen Überblick über den in der Kinder- und Jugendpsychiatrie, der Psychologie und der Sonderpädagogik erbrachten Forschungsstand zu Lernstörungen, die im klinischen Diagnosemanual der Weltgesundheitsorganisation als „Entwicklungsstörungen schulischer Fertigkeiten“ bezeichnet werden. Der Leser wird mit den allgemeinen Definitionen und Kriterien des Bereiches vertraut gemacht sowie mit den Beurteilungskriterien, Einschränkungen und aktuellen Prävalenzschätzungen. Für die Lese-Rechtschreibstörung, die Rechenstörung sowie für die kombinierten Störungen schulischer Fertigkeiten werden der aktuelle Forschungsstand zu Prävalenz, Ursachen, Diagnostik und effektiver Prävention bzw. Intervention dargestellt. (DIPF/Orig.

Study protocol for a randomised controlled trial of a cognitive-behavioural prevention programme for the children of parents with depression: the PRODO trial

Background: Depression is one of the most common psychiatric illnesses worldwide, but is nevertheless preventable. Since the children of parents who have depression are at greatest risk of developing depression themselves, prevention programmes for this population are a major public health priority. Here we report the study protocol of a randomised controlled trial of a group-based psychological intervention for families with i) at least one parent who suffers (or has suffered) from depression and ii) at least one child who has no current or previous psychiatric diagnosis. Methods/Design: Eligible families will be randomly allocated to receive either a German adaptation of the 12-session cognitive-behavioural Raising Healthy Children intervention (Gesund und glucklich aufwachsen; N = 50), or no intervention (usual care; N = 50). The primary outcome (child diagnosis of an episode of depression) will be assessed at 15-month follow-up. The secondary outcomes (child psychopathological symptoms) will be assessed immediately following completion of the intervention (6-months), as well as at 9-and 15-month follow-up. We hypothesise that children in the intervention condition, compared with those who do not receive the intervention, will show fewer symptoms of psychopathology, and be less likely to meet diagnostic criteria for a depressive episode, at follow-up. Discussion: Despite their elevated risk of developing depression, there is little formal support available for the children of parents with depression. This study provides an important step in the development of more effective depression prevention measures, which are needed if the personal, social and economic burden of depression is to be reduced

What does the brain of children with developmental dyslexia tell us about reading improvement? ERP evidence from an intervention study

Intervention is key to managing developmental dyslexia (DD), but not all children with DD benefit from treatment. Some children improve (improvers, IMP), whereas others do not improve (non-improvers, NIMP). Neurobiological differences between IMP and NIMP have been suggested, but studies comparing IMP and NIMP in childhood are missing. The present study examined whether ERP patterns change with treatment and differ between IMP and NIMP. We investigated the ERPs of 28 children with DD and 25 control children (CON) while performing a phonological lexical decision (PLD) task before and after a 6-month intervention. After intervention children with DD were divided into IMP (n = 11) and NIMP (n = 17). In the PLD-task children were visually presented with words, pseudohomophones, pseudowords, and false fonts and had to decide whether the presented stimulus sounded like an existing German word or not. Prior to intervention IMP showed higher N300 amplitudes over fronto-temporal electrodes compared to NIMP and CON and N400 amplitudes were attenuated in both IMP and NIMP compared to CON. After intervention N300 amplitudes of IMP were comparable to those of CON and NIMP. This suggests that the N300, which has been related to phonological access of orthographic stimuli and integration of orthographic and phonological representations, might index a compensatory mechanism or precursor that facilitates reading improvement. The N400, which is thought to reflect grapheme-phoneme conversion or the access to the orthographic lexicon increased in IMP from pre to post and was comparable to CON after intervention. Correlations between N300 amplitudes pre, growth in reading ability and N400 amplitudes post indicated that higher N300 amplitudes might be important for reading improvement and increase in N400 amplitudes showing the same cognitive profile might differ regarding their neuronal profile which could further influence reading improvement

The time course of reading processes in children with and without dyslexia: an ERP study

The main diagnostic criterion for developmental dyslexia (DD) in transparent orthographies is a remarkable reading speed deficit, which is often accompanied by spelling difficulties. These deficits have been traced back to both deficits in orthographic and phonological processing. For a better understanding of the reading speed deficit in DD it is necessary to clarify which processing steps are degraded in children with DD during reading. In order to address this question the present study used EEG to investigate three reading related ERPs: the N170, N400 and LPC. Twenty-nine children without DD and 52 children with DD performed a phonological lexical decision (PLD)-task, which tapped both orthographic and phonological processing. Children were presented with words, pseudohomophones, pseudowords and false fonts and had to decide whether the presented stimulus sounded like an existing German word or not. Compared to control children, children with DD showed deficits in all the investigated ERPs. Firstly, a diminished mean area under the curve for the word material-false font contrasts in the time window of the N170 was observed, indicating a reduced degree of print sensitivity; secondly, N400 amplitudes, as suggested to reflect the access to the orthographic lexicon and grapheme-phoneme conversion, were attenuated; and lastly, phonological access as indexed by the LPC was degraded in children with DD. Processing differences dependent on the linguistic material in children without DD were observed only in the LPC, suggesting that similar reading processes were adopted independent of orthographic familiarity. The results of this study suggest that effective treatment should include both orthographic and phonological training. Furthermore, more longitudinal studies utilizing the same task and stimuli are needed to clarify how these processing steps and their time course change during reading development