From the reward network to whole-brain metrics: structural connectivity in adolescents and young adults according to body mass index and genetic risk of obesity.

BACKGROUND: Obesity is a multifactorial condition. Genetic variants, such as the fat mass and obesity related gene (FTO) polymorphism, may increase the vulnerability of developing obesity by disrupting dopamine signaling within the reward network. Yet, the association of obesity, genetic risk of obesity, and structural connectivity of the reward network in adolescents and young adults remains unexplored. We investigate, in adolescents and young adults, the structural connectivity differences in the reward network and at the whole-brain level according to body mass index (BMI) and the FTO rs9939609 polymorphism. METHODS: One hundred thirty-two adolescents and young adults (age range: [10, 21] years, BMI z-score range: [-1.76, 2.69]) were included. Genetic risk of obesity was determined by the presence of the FTO A allele. Whole-brain and reward network structural connectivity were analyzed using graph metrics. Hierarchical linear regression was applied to test the association between BMI-z, genetic risk of obesity, and structural connectivity. RESULTS: Higher BMI-z was associated with higher (B = 0.76, 95% CI = [0.30, 1.21], P = 0.0015) and lower (B = -0.003, 95% CI = [-0.006, -0.00005], P = 0.048) connectivity strength for fractional anisotropy at the whole-brain level and of the reward network, respectively. The FTO polymorphism was not associated with structural connectivity nor with BMI-z. CONCLUSIONS: We provide evidence that, in healthy adolescents and young adults, higher BMI-z is associated with higher connectivity at the whole-brain level and lower connectivity of the reward network. We did not find the FTO polymorphism to correlate with structural connectivity. Future longitudinal studies with larger sample sizes are needed to assess how genetic determinants of obesity change brain structural connectivity and behavior.

A randomized controlled trial of a home-based computerized executive function intervention for children with cerebral palsy.

Children with cerebral palsy (CP) often show executive function (EF) impairments that are key to quality of life. The aim of this study was to assess whether a home-based computerized intervention program improves executive functions (EFs) compared to usual care. Sixty participants (30 females) with CP (8-12 years old) were paired by age, sex, motor ability, and intelligence quotient score and then randomized to intervention and waitlist control groups. The intervention group received a 12-week home-based computerized EF intervention (5 days/week, 30 min/day, total dose 30 h). Core and higher-order EFs were assessed before, immediately after, and 9 months after completing the intervention. The intervention group performed better than the waitlist control group in the three core EFs (immediately and 9 months after the intervention): inhibitory control (F = 7.58, p = 0.13 and F = 7.85, p = 0.12), working memory (F = 8.34, p = 0.14 and F = 7.55, p = 0.13), and cognitive flexibility (F = 4.87, p = 0.09 and F = 4.19, p = 0.08). No differences were found between the groups in higher-order EFs or EF manifestations in daily life. CONCLUSIONS: A home-based computerized EF intervention improved core EFs in children with CP, but further research is needed to identify strategies that allow the transfer of these improvements to everyday life. TRIAL REGISTRATION: NCT04025749 retrospectively registered on 19 July 2019. WHAT IS KNOWN: • One in two children with cerebral palsy has an intellectual impairment. Visual perception and executive functions are the most reported specific cognitive deficits. • The majority of interventions for cerebral palsy focus on motor impairments, but only a few randomized controlled trials have explored the effect of interventions on executive functions. WHAT IS NEW: • A home-based computerized cognitive intervention can improve the core executive functions of children with cerebral palsy. • Short- and long-term effects on core executive functions have been found.

Body mass index, systemic inflammation and cognitive performance in adolescents: A cross-sectional study.

BACKGROUND: Excessive body weight has been related to lower cognitive performance. One of the mechanisms through which excess body weight may affect cognition is inflammation. HYPOTHESIS: Our hypothesis is that both body mass index (BMI) and circulating levels of inflammatory biomarkers will be negatively related to cognitive performance. DESIGN: Cross-sectional study. SETTING: Users of the public health centres of the Consorci Sanitari de Terrassa (Terrassa, Spain) between 2010 and 2017 aged 12-21 years. PARTICIPANTS: One hundred and five adolescents (46 normoweight, 18 overweight, 41 obese). MEASUREMENTS: Levels of high sensitivity C-reactive protein, interleukin 6, tumour necrosis factor α (TNFα) and fibrinogen were determined from blood samples. Cognitive performance was evaluated and six cognitive composites were obtained: working memory, cognitive flexibility, inhibitory control, decision-making, verbal memory, and fine motor speed. A single multivariate general lineal model was used to assess the influence of the four inflammatory biomarkers, as well as participants' BMI, sex, and age on the 6 cognitive indexes. RESULTS: An inverse relationship between BMI and inhibitory control (F = 5.688, p = .019; ß = -0.212, p = .031), verbal memory (F = 5.404, p = .022; ß = -0.255, p = .009) and fine motor speed (F = 9.038, p = .003; ß = -0.319, p = .001) was observed. Levels of TNFα and fibrinogen were inversely related to inhibitory control (F = 5.055, p = .027; ß = -0.226, p = .021) and verbal memory (F = 4.732, p = .032; ß = -0.274, p = .005), respectively. LIMITATIONS: The cross-sectional nature of the study, the use of cognitive tests designed for clinical purposes, and the use of BMI as a proxy for adiposity are limitations of our study that must be taken into account when interpreting results. CONCLUSIONS: Our data indicate that some components of executive functions, together with verbal memory, are sensitive to specific obesity-related inflammatory agents at early ages.

COVID-19 severity is related to poor executive function in people with post-COVID conditions.

Patients with post-coronavirus disease 2019 (COVID-19) conditions typically experience cognitive problems. Some studies have linked COVID-19 severity with long-term cognitive damage, while others did not observe such associations. This discrepancy can be attributed to methodological and sample variations. We aimed to clarify the relationship between COVID-19 severity and long-term cognitive outcomes and determine whether the initial symptomatology can predict long-term cognitive problems. Cognitive evaluations were performed on 109 healthy controls and 319 post-COVID individuals categorized into three groups according to the WHO clinical progression scale: severe-critical (n = 77), moderate-hospitalized (n = 73), and outpatients (n = 169). Principal component analysis was used to identify factors associated with symptoms in the acute-phase and cognitive domains. Analyses of variance and regression linear models were used to study intergroup differences and the relationship between initial symptomatology and long-term cognitive problems. The severe-critical group performed significantly worse than the control group in general cognition (Montreal Cognitive Assessment), executive function (Digit symbol, Trail Making Test B, phonetic fluency), and social cognition (Reading the Mind in the Eyes test). Five components of symptoms emerged from the principal component analysis: the "Neurologic/Pain/Dermatologic" "Digestive/Headache", "Respiratory/Fever/Fatigue/Psychiatric" and "Smell/ Taste" components were predictors of Montreal Cognitive Assessment scores; the "Neurologic/Pain/Dermatologic" component predicted attention and working memory; the "Neurologic/Pain/Dermatologic" and "Respiratory/Fever/Fatigue/Psychiatric" components predicted verbal memory, and the "Respiratory/Fever/Fatigue/Psychiatric," "Neurologic/Pain/Dermatologic," and "Digestive/Headache" components predicted executive function. Patients with severe COVID-19 exhibited persistent deficits in executive function. Several initial symptoms were predictors of long-term sequelae, indicating the role of systemic inflammation and neuroinflammation in the acute-phase symptoms of COVID-19." Study Registration: www.ClinicalTrials.gov , identifier NCT05307549 and NCT05307575.

Factors Related to Quality of Life in Children With Cerebral Palsy.

BACKGROUND: We investigated the influence of relevant demographic, clinical, neuropsychological, and psychosocial variables on the proxy-reported quality of life (QOL) of children with cerebral palsy (CP). METHODS: The proxy-reported Cerebral Palsy Quality of Life-Child questionnaire (CP QOL-Child) was completed by 58 children with CP (mean age 10.22 years, SD 1.67). Relationships between QOL scores and demographic, clinical, neuropsychological, and psychosocial variables were assessed. CP QOL scores and other variables that correlated significantly were introduced into a multiple linear regression model. RESULTS: Executive functioning and motor functional status were explanatory variables for the CP QOL total score. Executive functions explained three specific QOL domains: Social Wellbeing and Acceptance, Feelings about Functioning, and Emotional Wellbeing and Self-esteem. Parental stress also explained Social Wellbeing and Acceptance. Motor functional status and visual perception were explanatory variables for the Access to Services domain. Finally, autism spectrum disorder (ASD) traits were an explanatory variable for the Participation and Physical Health domain. CONCLUSION: Executive functioning and motor functional status importantly influence QOL of children with CP. Visual perception, ASD symptoms, and parental stress variables are related with specific QOL domains. These findings demonstrate that interventions targeting cognitive functions in children with CP may positively influence QOL.

Interventions with an Impact on Cognitive Functions in Cerebral Palsy: a Systematic Review.

This systematic review aimed at investigating those interventions that impact on cognitive functioning in children and adults with cerebral palsy (CP). A systematic database search was conducted and twenty-eight studies suitable for inclusion were identified, of which only nine were randomized controlled trials (RCTs). Among all the studies included, ten were multi-modal (cognitive and physical tasks), eleven physical, five cognitive, and two alternative and augmentative communication interventions. The evidence suggests that multi-modal and physical interventions improve general cognitive functioning. Multi-modal and cognitive interventions have an impact on visual perception. Both interventions, together with physical interventions have an effect on a specific executive function domain (inhibitory control), and only cognitive interventions improved other executive function domains such as working memory. However, no RCT assessed the effects of all executive function domains. Few studies have looked at interventions to improve memory and language, and there is a scarcity of long-term research. Future RCTs must be of higher quality and better account for age and sex differences, as well as the clinical heterogeneity of CP. To date, there is evidence that multi-modal, cognitive or physical interventions have an impact on general cognitive functioning, visual perception and executive functions in children with CP, which may support their cognitive development.The protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO): CRD42020152616.

Neuropsychological impairment in post-COVID condition individuals with and without cognitive complaints.

One of the most prevalent symptoms of post-COVID condition is cognitive impairment, which results in a significant degree of disability and low quality of life. In studies with large sample sizes, attention, memory, and executive function were reported as long-term cognitive symptoms. This study aims to describe cognitive dysfunction in large post-COVID condition individuals, compare objective neuropsychological performance in those post-COVID condition individuals with and without cognitive complaints, and identify short cognitive exams that can differentiate individuals with post-COVID symptoms from controls. To address these aims, the Nautilus project was started in June 2021. During the first year, we collected 428 participants' data, including 319 post-COVID and 109 healthy controls (18-65 years old) from those who underwent a comprehensive neuropsychological battery for cognitive assessment. Scores on tests assessing global cognition, learning and long-term memory, processing speed, language and executive functions were significantly worse in the post-COVID condition group than in healthy controls. Montreal Cognitive Assessment, digit symbol test, and phonetic verbal fluency were significant in the binomial logistic regression model and could effectively distinguish patients from controls with good overall sensitivity and accuracy. Neuropsychological test results did not differ between those with and without cognitive complaints. Our research suggests that patients with post-COVID conditions experience significant cognitive impairment and that routine tests like the Montreal Cognitive Assessment, digit symbol, and phonetic verbal fluency test might identify cognitive impairment. Thus, the administration of these tests would be helpful for all patients with post-COVID-19 symptoms, regardless of whether cognitive complaints are present or absent. Study registration: www.ClinicalTrials.gov, identifiers NCT05307549 and NCT05307575.

Improving Reading Skills Using a Computerized Phonological Training Program in Early Readers with Reading Difficulties.

In the last years, there has been a big effort to identify risk factors for reading difficulties and to develop new methodologies to help struggling readers. It has been shown that early intervention is more successful than late intervention, and that intensive training programs can benefit children with reading difficulties. The aim of our study is to investigate the effectiveness of an intensive computerized phonological training program designed to improve reading performance in a sample of children with reading difficulties at the early stages of their reading learning process. Thirty-two children with reading difficulties were randomly assigned to one of the two intervention groups: RDIR (children with reading difficulties following a computerized intensive remediation strategy) (n = 20) (7.01 ± 0.69 years), focused on training phonemic awareness, decoding and reading fluency through the computational training; and RDOR (children with reading difficulties following an ordinary remediation strategy) (n = 12) (6.92 ± 0.82 years), which consisted of a reinforcement of reading with a traditional training approach at school. Normal readers (NR) were assigned to the control group (n = 24) (7.32 ± 0.66 years). Our results indicate that both the RDIR and RDOR groups showed an increased reading performance after the intervention. However, children in the RDIR group showed a stronger benefit than the children in the RDOR group, whose improvement was weaker. The control group did not show significant changes in reading performance during the same period. In conclusion, results suggest that intensive early intervention based on phonics training is an effective strategy to remediate reading difficulties, and that it can be used at school as the first approach to tackle such difficulties.

Alterations in Brain Network Organization in Adults With Obesity as Compared With Healthy-Weight Individuals and Seniors.

OBJECTIVE: Life expectancy and obesity rates have drastically increased in recent years. An unhealthy weight is related to long-lasting medical disorders that might compromise the normal course of aging. The aim of the current study of brain connectivity patterns was to examine whether adults with obesity would show signs of premature aging, such as lower segregation, in large-scale networks. METHODS: Participants with obesity (n = 30, mean age = 32.8 ± 5.68 years) were compared with healthy-weight controls (n = 33, mean age = 30.9 ± 6.24 years) and senior participants who were stroke-free and without dementia (n = 30, mean age = 67.1 ± 6.65 years) using resting-state magnetic resonance imaging and graph theory metrics (i.e., small-world index, clustering coefficient, characteristic path length, and degree). RESULTS: Contrary to our hypothesis, participants with obesity exhibited a higher clustering coefficient compared with senior participants (t = 5.06, p < .001, d = 1.23, 95% CIbca = 0.64 to 1.88). Participants with obesity also showed lower global degree relative to seniors (t = -2.98, p = .014, d = -0.77, 95% CIbca = -1.26 to -0.26) and healthy-weight controls (t = -2.92, p = .019, d = -0.72, 95% CIbca = -1.19 to -0.25). Regional degree alterations in this group were present in several functional networks. CONCLUSIONS: Participants with obesity displayed greater network clustering than did seniors and also had lower degree compared with seniors and individuals with normal weight, which is not consistent with the notion that obesity is associated with premature aging of the brain. Although the cross-sectional nature of the study precludes causal inference, the overly clustered network patterns in obese participants could be relevant to age-related changes in brain function because regular networks might be less resilient and metabolically inefficient.

Functional connectivity alterations associated with literacy difficulties in early readers.

The link between literacy difficulties and brain alterations has been described in depth. Resting-state fMRI (rs-fMRI) has been successfully applied to the study of intrinsic functional connectivity (iFc) both in dyslexia and typically developing children. Most related studies have focused on the stages from late childhood into adulthood using a seed to voxel approach. Our study analyzes iFc in an early childhood sample using the multivariate pattern analysis. This facilitates a hypothesis-free analysis and the possible identification of abnormal functional connectivity patterns at a whole brain level. Thirty-four children with literacy difficulties (LD) (7.1 ± 0.69 yr.) and 30 typically developing children (TD) (7.43 ± 0.52 yr.) were selected. Functional brain connectivity was measured using an rs-fMRI acquisition. The LD group showed a higher iFc between the right middle frontal gyrus (rMFG) and the default mode network (DMN) regions, and a lower iFc between the rMFG and both the bilateral insular cortex and the supramarginal gyrus. These results are interpreted as a DMN on/off routine malfunction in the LD group, which suggests an alteration of the task control network regulating DMN activity. In the LD group, the posterior cingulate cortex also showed a lower iFc with both the middle temporal poles and the fusiform gyrus. This could be interpreted as a failure in the integration of information between brain regions that facilitate reading. Our results show that children with literacy difficulties have an altered functional connectivity in their reading and attentional networks at the beginning of the literacy acquisition. Future studies should evaluate whether or not these alterations could indicate a risk of developing dyslexia.

Is cognitive training an effective tool for improving cognitive function and real-life behaviour in healthy children and adolescents? A systematic review.

Computerised cognitive training (CCT) has been applied to improve cognitive function in pathological conditions and in healthy populations. Studies suggest that CCT produces near-transfer effects to cognitive functions, with less evidence for far-transfer. Newer applications of CTT in adults seem to produce certain far-transfer effects by influencing eating behaviour and weight loss. However, this is more unexplored in children and adolescents. We conducted a systematic review of 16 studies with randomised controlled design to assess the impact of CCT on cognitive functioning and real-life outcomes, including eating behaviour, in children and adolescents with typical development (PROSPERO registration number: CRD42019123889). Results show near-transfer effects to working memory, with inconsistent results regarding far-transfer effects to other cognitive functions and real-life measures. Long-term effects show the same trend. Far-transfer effects occurred after cue-related inhibitory control and attentional training, although effects seem not to last. CCT may be a potential weight-loss treatment option but more research is needed to determine the specific characteristics to enhance treatment outcomes.

Trastorno del espectro alcohólico fetal: Un trastorno del neurodesarrollo infradiagnosticado y de pronóstico incierto / Fetal alcohol spectrum disorder. An underdiagnosed neuro-development disorder of uncertain prognosis

La exposición prenatal al alcohol es causa de alteraciones somáticas, cognitivas y conductuales que se agrupan bajo el término de trastorno del espectro alcohólico fetal (TEAF). La evolución a largo plazo de los sujetos afectados a menudo es desfavorable, especialmente a nivel académico y adaptativo social. En el perfil neuropsicológico es característica la disfunción ejecutiva a menudo asociada a trastornos de la conducta que evolucionan en muchos casos hacia la delincuencia a partir de la adolescencia y en la edad adulta. Se han descrito también déficits de las habilidades sociales y la empatía. La exposición prenatal al alcohol constituye la causa más frecuente de trastorno del neurodesarrollo adquirido y prevenible.

Prenatal exposure to alcohol is the cause of cognitive and behavioural disorders grouped under the term fetal alcohol spectrum disorders (FASD). The long-term evolution of subjects with FASD is often unfavourable, especially in social and academic fields. Executive dysfunction is a hallmark deficit for children with FASD with increased rates of externalizing behaviours, such as aggressiveness and frequently delinquency in adolescence and adulthood. Deficits in social skills, empathy and communication ability are frequent observed among FASD. Prenatal exposure to alcohol is the most frequent cause of acquired and preventable neurodevelopmental disorder.

Effect of the catechol-O-methyltransferase Val 158 Met polymorphism on theory of mind in obesity.

Obesity is often accompanied with psychosocial adjustment problems, such as difficulties in social interactions and social withdrawal. A key aspect of social cognition is theory of mind, which allows inferring mental states, feelings, motivations, and beliefs of others and to use this information to predict their future behaviour. Theory of mind is highly dependent on prefrontal dopaminergic neurotransmission, which is regulated by catechol-O-methyltransferase (COMT) activity. We aimed at determining whether theory of mind is altered in obesity and if this ability is modulated by COMT. Fifty patients with obesity and 47 normal-weight individuals underwent the Reading the Mind in the Eyes Test, the Wisconsin Card Sorting Test, and the Vocabulary subscale of the Wechsler Adult Intelligence Scale. The genotype for the COMT Val 158 Met functional polymorphism was determined for all subjects. Patients with obesity obtained significantly lower scores in the negative items of the Reading the Mind in the Eyes Test than normal-weight subjects. Further, an interaction effect was observed between group and COMT genotype. Specifically, the presence of the Met allele was associated to a better identification of negative mental states only in patients with obesity. Our results indicate that obesity is accompanied with difficulties in theory of mind and that this ability is influenced by the COMT genotype.

[Fetal alcohol spectrum disorder. An underdiagnosed neuro-development disorder of uncertain prognosis]. / Trastorno del espectro alcohólico fetal. Un trastorno del neurodesarrollo infradiagnosticado y de pronóstico incierto.

Prenatal exposure to alcohol is the cause of cognitive and behavioural disorders grouped under the term fetal alcohol spectrum disorders (FASD). The long-term evolution of subjects with FASD is often unfavourable, especially in social and academic fields. Executive dysfunction is a hallmark deficit for children with FASD with increased rates of externalizing behaviours, such as aggressiveness and frequently delinquency in adolescence and adulthood. Deficits in social skills, empathy and communication ability are frequent observed among FASD. Prenatal exposure to alcohol is the most frequent cause of acquired and preventable neurodevelopmental disorder.

La exposición prenatal al alcohol es causa de alteraciones somáticas, cognitivas y conductuales que se agrupan bajo el término de trastorno del espectro alcohólico fetal (TEAF). La evolución a largo plazo de los sujetos afectados a menudo es desfavorable, especialmente a nivel académico y adaptativo social. En el perfil neuropsicológico es característica la disfunción ejecutiva a menudo asociada a trastornos de la conducta que evolucionan en muchos casos hacia la delincuencia a partir de la adolescencia y en la edad adulta. Se han descrito también déficits de las habilidades sociales y la empatía. La exposición prenatal al alcohol constituye la causa más frecuente de trastorno del neurodesarrollo adquirido y prevenible.

Allostatic Load Is Linked to Cortical Thickness Changes Depending on Body-Weight Status.

Objective: Overweight (body mass index or BMI ≥ 25 kg/m2) and stress interact with each other in complex ways. Overweight promotes chronic low-inflammation states, while stress is known to mediate caloric intake. Both conditions are linked to several avoidable health problems and to cognitive decline, brain atrophy, and dementia. Since it was proposed as a framework for the onset of mental illness, the allostatic load model has received increasing attention. Although changes in health and cognition related to overweight and stress are well-documented separately, the association between allostatic load and brain integrity has not been addressed in depth, especially among overweight subjects. Method: Thirty-four healthy overweight-to-obese and 29 lean adults underwent blood testing, neuropsychological examination, and magnetic resonance imaging to assess the relationship between cortical thickness and allostatic load, represented as an index of 15 biomarkers (this is, systolic and diastolic arterial tension, glycated hemoglobin, glucose, creatinine, total cholesterol, HDL and LDL cholesterol, triglycerides, c-reactive protein, interleukin-6, insulin, cortisol, fibrinogen, and leptin). Results: Allostatic load indexes showed widespread positive and negative significant correlations (p < 0.01) with cortical thickness values depending on body-weight status. Conclusion: The increase of allostatic load is linked to changes in the gray matter composition of regions monitoring behavior, sensory-reward processing, and general cognitive function.

Processing of primary and secondary rewards: a quantitative meta-analysis and review of human functional neuroimaging studies.

One fundamental question concerning brain reward mechanisms is to determine how reward-related activity is influenced by the nature of rewards. Here, we review the neuroimaging literature and explicitly assess to what extent the representations of primary and secondary rewards overlap in the human brain. To achieve this goal, we performed an activation likelihood estimation (ALE) meta-analysis of 87 studies (1452 subjects) comparing the brain responses to monetary, erotic and food reward outcomes. Those three rewards robustly engaged a common brain network including the ventromedial prefrontal cortex, ventral striatum, amygdala, anterior insula and mediodorsal thalamus, although with some variations in the intensity and location of peak activity. Money-specific responses were further observed in the most anterior portion of the orbitofrontal cortex, supporting the idea that abstract secondary rewards are represented in evolutionary more recent brain regions. In contrast, food and erotic (i.e. primary) rewards were more strongly represented in the anterior insula, while erotic stimuli elicited particularly robust responses in the amygdala. Together, these results indicate that the computation of experienced reward value does not only recruit a core "reward system" but also reward type-dependent brain structures.

A cross-sectional and follow-up functional MRI study with a working memory task in adolescent anorexia nervosa.

Structural and functional brain abnormalities have been described in anorexia nervosa (AN). The objective of this study was to examine whether there is abnormal regional brain activation during a working memory task not associated with any emotional stimuli in adolescent patients with anorexia and to detect possible changes after weight recovery. Fourteen children and adolescents (age range 11-18 years) consecutively admitted with DSM-IV diagnosis of AN and fourteen control subjects of similar age were assessed by means of psychopathological scales and functional magnetic resonance imaging (fMRI) during a working memory task. After seven months of treatment and weight recovery, nine AN patients were reassessed. Before treatment, the AN group showed significantly higher activation than controls in temporal and parietal areas and especially in the temporal superior gyrus during performance of the cognitive task. Control subjects did not show greater activation than AN patients in any region. A negative correlation was found between brain activation and body mass index and a positive correlation between activation and depressive symptomatology. At follow-up after weight recovery, AN patients showed a decrease in brain activation in these areas and did not present differences with respect to controls. These results show that adolescent AN patients showed hyperactivation in the parietal and especially the temporal lobe during a working memory task, suggesting that they must make an additional effort to perform at normal levels. This activation correlated with clinical variables. In these young patients, differences with respect to controls disappeared after weight recovery.

Cerebellar deficits in schizophrenia are associated with executive dysfunction.

Cerebellar abnormalities have been documented in schizophrenia in postmortem, functional and volumetric neuroimaging studies. This study aims to establish the relationship between structural changes in the cerebellum and executive dysfunction in patients with schizophrenia using voxel-based morphometry. We compared 28 outpatients with 28 healthy controls. A widely used executive battery and the voxel-based morphometry approach were used to investigate possible structural cerebellum changes on magnetic resonance imaging. Working memory dysfunctions in schizophrenia correlated with grey matter in both cerebellar hemispheres and vermis. Mental flexibility dysfunctions also correlated with reductions in white matter volume in bilateral cerebellum. This evidence supports the contribution of cerebellar grey and white matter deficits to executive dysfunctions observed in schizophrenia.

Proton magnetic resonance spectroscopy reveals medial temporal metabolic abnormalities in adolescents with history of preterm birth.

Prematurity is associated with volumetric reductions in specific brain areas such as the hippocampus and with metabolic changes that can be detected by spectroscopy. Short echo time (35 ms) Proton magnetic resonance spectroscopy (1H MRS) was performed to assess possible medial temporal lobe metabolic abnormalities in 21 adolescents with preterm birth (mean age: 14.8, SD: 1.3) compared with an age-matched control sample (mean age: 14.8, SD: 1.6). 1H MRS spectra were analyzed with linear combination model fitting, obtaining the absolute metabolite concentrations for Creatine (Cr), and myo-inositol (Ins). In addition, the following metabolite sums were measured: total Cho (glycerophospho-choline + phosphocholine), total N-acetyl-aspartate + N-acetyl-aspartylglutamate (NA), and total Glx (glutamate + glutamine). A stereological analysis was performed to calculate hippocampal volume. Absolute Cr, and total NA values were decreased in the preterm group (p = 0.016; p = 0.002, respectively). The preterm also showed a hippocampal reduction (p < 0.0001). Significant relationships were found between gestational age and different metabolites and the hippocampal volume. Moreover, hippocampal volume correlated with brain metabolites in the whole sample. Results demonstrate that prematurity affects medial temporal lobe metabolites, and that the alteration is related to structural changes, suggesting that the cerebral changes persist until adolescence.