Source monitoring for actions in adolescents with 22q11.2 deletion syndrome (22q11DS)

Background Source monitoring consists in identifying the origin of mental events. Recent research suggests that confusions over internally generated mental events may represent a cognitive marker for increased proneness to psychotic symptoms and disorders. We have examined source monitoring for actions in adolescents with the 22q11.2 deletion syndrome (22q11DS), a neurogenetic disease associated with high rates of schizophrenia during adulthood, and expected to observe source monitoring deficits in comparison to IQ-matched and typically developing controls. Method Eighteen adolescents with 22q11DS, 17 adolescents matched for age and IQ, and also 17 adolescents matched for age participated in this study. Our adapted action monitoring paradigm asked subjects to visualize a series of actions in three different conditions: (1) visualize themselves performing the action; (2) visualize the experimenter performing the action; or (3) simply repeat the action statements without visualization of the action performer. Results The adolescents with 22q11DS performed adequately in terms of recognition (hits), but in comparison to both control groups, they committed more source confusions on correctly recognized items. Further examination revealed that the adolescents were more likely to demonstrate confusions between exterior sources in which the self was not involved. Conclusions Source monitoring deficits can be observed in adolescents with 22q11DS, a syndrome putting them at high risk for developing schizophrenia. These deficits are discussed in terms of early cognitive processes associated with genetic risk for schizophreni

Understanding others: a pilot investigation of cognitive and affective facets of social cognition in patients with 22q11.2 deletion syndrome (22q11DS)

Background Although significant impairments in the affective and cognitive facets of social cognition have been highlighted in patients with 22q11.2 deletion syndrome (22q11DS) in previous studies, these domains have never been investigated simultaneously within the same group of participants. Furthermore, despite theoretical evidence, associations between these two processes and schizotypal symptoms or social difficulties in this population have been scarcely examined. Methods Twenty-nine participants with 22q11DS and 27 typically developing controls (N = 5 siblings; N = 22 unrelated controls) aged between 11 and 21 years participated in the study. Both groups were matched for age and gender distribution. Two computerized social cognition tasks evaluating perspective and emotion recognition abilities were administered to all participants. The levels of schizotypal trait expression and social functioning were further investigated in both groups, based on a validated self-report questionnaire (Schizotypal Personality Questionnaire) and parental interview (Vineland Adaptive Behavior Scales). Results Participants with 22q11DS exhibited lower perspective-taking and emotion recognition capacities than typically developing controls. The two socio-cognitive dimensions investigated here were further correlated in healthy controls. The efficiency of perspective-taking processes (response time) was marginally related to the degree of schizotypal trait expression in patients with 22q11DS. Conclusions This study first provides support for significant deficits in two core facets of social cognition in 22q11DS. The associations observed between the experimental tasks and measures of social functioning or schizotypal symptoms in 22q11DS open promising research avenue, which should be more deeply investigated in future studies

Longitudinal Relationships Between Reflective Functioning, Empathy, and Externalizing Behaviors During Adolescence and Young Adulthood

Reflective functioning (RF) refers to the understanding of one’s own and others’ behaviors in terms of mental states, whereas empathy entails the abilities to understand (cognitive empathy) and to share (affective empathy) the emotions of others. Low RF and low empathy have been previously related to externalizing behaviors, such as aggression and rule breaking. However, few longitudinal studies have simultaneously examined the relationships between these variables during adolescence. The aim of the present study is to investigate the longitudinal effects of both RF and empathy on potential changes in externalizing behaviors over time, in a group of 103 adolescents and young adults from the general population assessed repeatedly up to four times. We conducted multilevel analysis in order to examine the effects of RF and empathy on the initial levels and the trajectories of externalizing behaviors over time, while accounting for other variables previously associated with externalizing behaviors, such as age, gender, internalizing problems, and cognitive abilities. The results suggest that the ability to reflect on behaviors in terms of mental states predicted a sharper decrease in externalizing behaviors over time. Moreover, externalizing behaviors at the first assessment were associated with RF impairments and low affective empathy. Age, gender, cognitive abilities, and cognitive empathy were not associated with externalizing behaviors. We discuss how our results, based on a typically developing population, might inform primary or indicated prevention strategies for externalizing behaviors by focusing on socio-cognitive processes such as RF and affective empathy

No age effect in the prevalence and clinical significance of ultra-high risk symptoms and criteria for psychosis in 22q11 deletion syndrome: Confirmation of the genetically driven risk for psychosis?

BACKGROUND: The 22q11.2 deletion syndrome (22q11DS) is one of the highest known risk factors for schizophrenia. Thus, the detection of 22q11DS patients at particularly high risk of psychosis is important, yet studies on the clinical significance of the widely used ultra-high risk (UHR) criteria in 22q11DS are inconclusive. Since age was reported to moderate clinical significance of UHR symptoms in community samples, we explored whether age at presentation of UHR symptoms and criteria may explain part of this heterogeneity. METHODS: 111 patients with 22q11DS (8-30 years; 15.7±4.7) were assessed for UHR symptoms/criteria. Information on diagnoses, psychosocial functioning, and IQ were collected. RESULTS: Any UHR symptom was reported by 38.7%, any UHR criterion by 27%. No significant influence of age on the prevalence of UHR symptoms or criteria was detected. Moreover, age did not significantly modulate the association between UHR symptoms and functioning. However, significant interaction terms suggested that younger age groups were more likely to meet UHR criteria in the presence of UHR symptoms compared to the adult group. DISCUSSION: Compared to the general population, prevalence of UHR symptoms and criteria was 3.8-fold and 20.8-fold in our 22q11DS sample. Contrary to the general population, age only modulated the prevalence of UHR criteria among those with UHR symptoms, but not their prevalence per se or their clinical significance. This suggests that UHR symptoms might develop as a trait factor in terms of a genetically driven schizotypal disposition in 22q11DS, thus necessitating future studies on psychosis-risk indicators in this genetic high-risk group

Visual memory profile in 22q11.2 microdeletion syndrome: are there differences in performance and neurobiological substrates between tasks linked to ventral and dorsal visual brain structures? A cross-sectional and longitudinal study

BACKGROUND: Children affected by the 22q11.2 deletion syndrome (22q11.2DS) have a specific neuropsychological profile with strengths and weaknesses in several cognitive domains. Specifically, previous evidence has shown that patients with 22q11.2DS have more difficulties memorizing faces and visual-object characteristics of stimuli. In contrast, they have better performance in visuo-spatial memory tasks. The first focus of this study was to replicate these results in a larger sample of patients affected with 22q11.2DS and using a range of memory tasks. Moreover, we analyzed if the deficits were related to brain morphology in the structures typically underlying these abilities (ventral and dorsal visual streams). Finally, since the longitudinal development of visual memory is not clearly characterized in 22q11.2DS, we investigated its evolution from childhood to adolescence. METHODS: Seventy-one patients with 22q11.2DS and 49 control individuals aged between 9 and 16 years completed the Benton Visual Retention Test (BVRT) and specific subtests assessing visual memory from the Children’s Memory Scale (CMS). The BVRT was used to compute spatial and object memory errors. For the CMS, specific subtests were classified into ventral, dorsal, and mixed subtests. Longitudinal data were obtained from a subset of 26 patients and 22 control individuals. RESULTS: Cross-sectional results showed that patients with 22q11.2DS were impaired in all visual memory measures, with stronger deficits in visual-object memory and memory of faces, compared to visuo-spatial memory. No correlations between morphological brain impairments and visual memory were found in patients with 22q11.2DS. Longitudinal findings revealed that participants with 22q11.2DS made more object memory errors than spatial memory errors at baseline. This difference was no longer significant at follow-up. CONCLUSIONS: Individuals with 22q11.2DS have impairments in visual memory abilities, with more pronounced difficulties in memorizing faces and visual-object characteristics. From childhood to adolescence, the visual cognitive profile of patients with 22q11.2DS seems globally stable even though some processes show an evolution with time. We hope that our results will help clinicians and caregivers to better understand the memory difficulties of young individuals with 22q11.2DS. This has a particular importance at school to facilitate recommendations concerning intervention strategies for these young patients

Cortical folding in Broca's area relates to obstetric complications in schizophrenia patients and healthy controls

Background The increased occurrence of obstetric complications (OCs) in patients with schizophrenia suggests that alterations in neurodevelopment may be of importance to the aetiology of the illness. Abnormal cortical folding may reflect subtle deviation from normal neurodevelopment during the foetal or neonatal period. In the present study, we hypothesized that OCs would be related to cortical folding abnormalities in schizophrenia patients corresponding to areas where patients with schizophrenia display altered cortical folding when compared with healthy controls. Method In total, 54 schizophrenia patients and 54 healthy control subjects underwent clinical examination and magnetic resonance image scanning on a 1.5 T scanner. Information on OCs was collected from original birth records. An automated algorithm was used to calculate a three-dimensional local gyrification index (lGI) at numerous points across the cortical mantle. Results In both schizophrenia patients and healthy controls, an increasing number of OCs was significantly related to lower lGI in the left pars triangularis (p<0.0005) in Broca's area. For five other anatomical cortical parcellations in the left hemisphere, a similar trend was demonstrated. No significant relationships between OCs and lGI were found in the right hemisphere and there were no significant case-control differences in lGI. Conclusions The reduced cortical folding in the left pars triangularis, associated with OCs in both patients and control subjects suggests that the cortical effect of OCs is caused by factors shared by schizophrenia patients and healthy controls rather than factors related to schizophrenia alon

Face processing in 22q11.2 deletion syndrome: atypical development and visual scanning alterations

BACKGROUND: Previous research links social difficulties to atypical face exploration in 22q11.2 deletion syndrome (22q11.2DS). Two types of face processing are distinguished: configural (CFP) and featural (FFP). CFP develops later in life and plays an important role in face and emotion recognition abilities. Recent studies reported atypical development of CFP in several neurodevelopmental disorders. Taking previous reports of atypical face exploration one step further, our study aims at characterizing face processing in children and adolescents with 22q11.2DS. First, we sought to identify biases in the first two fixation positions on faces and to detect differences between CFP and FFP in 22q11.2DS using eye-tracking technology. Second, we investigated the developmental trajectories of CFP and FFP using accuracy data from follow-up evaluation. METHODS: Seventy-five individuals with 22q11.2DS and 84 typically developed (TD) individuals (aged 6-21 years) completed a discrimination task ("Jane task") inducing CFP and FFP in an eye-tracking setting. Thirty-six individuals with 22q11DS and 30 TD from our sample completed a longitudinal follow-up evaluation. RESULTS: Findings revealed that individuals with 22q11.2DS demonstrate an early bias toward the mouth region during the initial fixations on the faces and reduced flexibility exploration of the faces, with a reduced number of transitions between faces and longer fixations compared to the TD group. Further, scanpaths did not differ between CFP and FFP in the 22q11.2DS group. Longitudinal analysis of accuracy data provided evidence for atypical development of CFP in 22q11.2DS. CONCLUSIONS: The current study brings new evidence of altered face exploration in 22q11.2DS and identifies developmental mechanisms that may contribute to difficulties impacting social interactions in the syndrome

Regional cortical volumes and congenital heart disease: a MRI study in 22q11.2 deletion syndrome

Children with congenital heart disease (CHD) who survive surgery often present impaired neurodevelopment and qualitative brain anomalies. However, the impact of CHD on total or regional brain volumes only received little attention. We address this question in a sample of patients with 22q11.2 deletion syndrome (22q11DS), a neurogenetic condition frequently associated with CHD. Sixty-one children, adolescents, and young adults with confirmed 22q11.2 deletion were included, as well as 80 healthy participants matched for age and gender. Subsequent subdivision of the patients group according to CHD yielded a subgroup of 27 patients with normal cardiac status and a subgroup of 26 patients who underwent cardiac surgery during their first years of life (eight patients with unclear status were excluded). Regional cortical volumes were extracted using an automated method and the association between regional cortical volumes, and CHD was examined within a three-condition fixed factor. Robust protection against type I error used Bonferroni correction. Smaller total cerebral volumes were observed in patients with CHD compared to both patients without CHD and controls. The pattern of bilateral regional reductions associated with CHD encompassed the superior parietal region, the precuneus, the fusiform gyrus, and the anterior cingulate cortex. Within patients, a significant reduction in the left parahippocampal, the right middle temporal, and the left superior frontal gyri was associated with CHD. The present results of global and regional volumetric reductions suggest a role for disturbed hemodynamic in the pathophysiology of brain alterations in patients with neurodevelopmental disease and cardiac malformations

Adaptive Strategy for the Statistical Analysis of Connectomes

We study an adaptive statistical approach to analyze brain networks represented by brain connection matrices of interregional connectivity (connectomes). Our approach is at a middle level between a global analysis and single connections analysis by considering subnetworks of the global brain network. These subnetworks represent either the inter-connectivity between two brain anatomical regions or by the intra-connectivity within the same brain anatomical region. An appropriate summary statistic, that characterizes a meaningful feature of the subnetwork, is evaluated. Based on this summary statistic, a statistical test is performed to derive the corresponding p-value. The reformulation of the problem in this way reduces the number of statistical tests in an orderly fashion based on our understanding of the problem. Considering the global testing problem, the p-values are corrected to control the rate of false discoveries. Finally, the procedure is followed by a local investigation within the significant subnetworks. We contrast this strategy with the one based on the individual measures in terms of power. We show that this strategy has a great potential, in particular in cases where the subnetworks are well defined and the summary statistics are properly chosen. As an application example, we compare structural brain connection matrices of two groups of subjects with a 22q11.2 deletion syndrome, distinguished by their IQ scores

Visual processing deficits in 22q11.2 Deletion Syndrome.

Carriers of the rare 22q11.2 microdeletion present with a high percentage of positive and negative symptoms and a high genetic risk for schizophrenia. Visual processing impairments have been characterized in schizophrenia, but less so in 22q11.2 Deletion Syndrome (DS). Here, we focus on visual processing using high-density EEG and source imaging in 22q11.2DS participants (N = 25) and healthy controls (N = 26) with an illusory contour discrimination task. Significant differences between groups emerged at early and late stages of visual processing. In 22q11.2DS, we first observed reduced amplitudes over occipital channels and reduced source activations within dorsal and ventral visual stream areas during the P1 (100-125 ms) and within ventral visual cortex during the N1 (150-170 ms) visual evoked components. During a later window implicated in visual completion (240-285 ms), we observed an increase in global amplitudes in 22q11.2DS. The increased surface amplitudes for illusory contours at this window were inversely correlated with positive subscales of prodromal symptoms in 22q11.2DS. The reduced activity of ventral and dorsal visual areas during early stages points to an impairment in visual processing seen both in schizophrenia and 22q11.2DS. During intervals related to perceptual closure, the inverse correlation of high amplitudes with positive symptoms suggests that participants with 22q11.2DS who show an increased brain response to illusory contours during the relevant window for contour processing have less psychotic symptoms and might thus be at a reduced prodromal risk for schizophrenia