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The prevalence of psychiatric disorders in people with epilepsy is as high as 43% and, among them, psychoses represent a severe comorbidity.
Aims
This is a narrative review discussing the interplay between epilepsy and psychosis and identifying challenges in diagnosing and managing psychotic symptoms in epilepsy, focusing on the past 10 years.
Method
Articles published between June 2014 and December 2024 were identified through searches in PubMed using the search terms ‘psychosis’, ’seizure, epilepsy and convulsion’, ‘epile*’, ’seizure*’ and ‘convuls*’.
Results
The association between epilepsy and psychosis was shown to be bidirectional, with people with psychosis being at increased risk of epilepsy. In epilepsy, psychotic symptoms may occur in three clinical scenarios, with clinical presentation and management varying in relationship to these: seizure-related (peri-ictal), treatment-related or independent of the former.
Conclusions
There are no guidelines for the management of psychotic symptoms in epilepsy, but it is possible to apply policies for the treatment of psychoses, taking into account the peculiarities and needs of people with epilepsy.
Complex post-traumatic stress disorder (cPTSD) is a newly recognized condition characterized by core PTSD symptoms and disturbances in self-organization (DSO) that has been associated with psychotic-like experiences (PLEs). This study employs two psychopathology network approaches to identify which post-traumatic symptoms are related to PLEs in a sample of late adolescents. We propose that cPTSD symptoms play a crucial role in explaining the co-occurrence of trauma and PLEs.
Methods
A sample of 1010 late adolescents provided measures of post-traumatic symptomatology and PLEs. We estimated the Gaussian graphical network structure of PTSD/cPTSD symptoms and PLEs and assessed their bridge centrality indices. Bayesian network analysis was then used to estimate a directed acyclic graph (DAG). Gender was set as a moderator in both Gaussian and Bayesian models.
Results
Results show that affect dysregulation, a cPTSD domain, presented the highest bridge connection with the PLE cluster. Bayesian network analysis identified a pathway going from cPTSD items of worthlessness and relational dysregulation, to PLE items of paranoia and social anxiety. Additionally, we found relevant gender differences in network connectivity, with females showing higher connectivity compared to males.
Conclusions
Our findings highlight the central role of affect dysregulation and negative self-concept in linking cPTSD to PLE symptoms, with specific differences according to gender. These insights underscore the need for targeted, gender-sensitive approaches in the prevention and treatment of PLEs among adolescents, emphasizing early intervention and tailored treatment strategies.
The revival of psilocybin in psychopharmacological research heralds a potential paradigm shift for treating mood and anxiety disorders, and other psychiatric conditions beyond the psychotic spectrum. This critical review evaluates current evidence on psilocybin’s efficacy, juxtaposing potential benefits with the practical aspects of psychedelic-assisted psychotherapy (PAP) and the methodological constraints of existing research.
An electronic literature search was conducted using PubMed/MEDLINE, selecting studies published up to December 2023 that explored the clinical use of psilocybin in mood and anxiety disorders, obsessive-compulsive disorder, post-traumatic stress disorder, and substance use disorder. Despite promising preliminary results suggesting psilocybin’s efficacy in alleviating depression and anxiety, as well as obsessions, compulsions, and addictive behaviors, significant evidence gaps persist. These include evaluating the efficacy of psilocybin compared to standard antidepressants or anxiolytic molecules and identifying patient subpopulations that might benefit most from PAP. Concerns about psilocybin’s safety, long-term efficacy, and optimal dosage remain unclear due to previous trials’ limitations. Real-world implementation faces challenges, including infrastructural requirements, personnel training, and unresolved legal and ethical issues. This paper argues for further research to substantiate the evidence base, emphasizing the need for larger studies that overcome current methodological limitations and explore psilocybin’s full therapeutic potential. While psilocybin holds promise for psychiatry, its successful translation from research to clinical practice demands more robust evidence on efficacy, safety, and methodological rigor. In addition, other factors, such as cultural stigma and legal/ethical issues, need to be successfully addressed to facilitate psilocybin’s implementation in healthcare systems.
Social health (SH) markers, including marital status, contact frequency, network size, and social support, have been linked with increased cognitive capability. However, the underlying mechanisms remain poorly understood. We aim to investigate whether depression symptoms and inflammatory biomarkers mediate associations between SH and cognitive outcomes.
Methods:
We used data from waves 1-9 of the English Longitudinal Study of Ageing, involving 7,136 participants aged 50 or older at baseline. First, we examined associations between SH (wave 1) and depression and inflammatory biomarkers (C-reactive protein (CRP) and fibrinogen) (wave 2) using linear regression models. Second, we tested associations between a) SH and b) depression and inflammation with subsequent standardised verbal fluency and memory in wave 3 and change between waves 3-9, indexed using slopes derived from multilevel models. We adjusted for age, sex, socio-economic position, cardiovascular disease, basic and instrumental activities of daily living, health behaviours, and baseline depression symptoms and cognition. We will also conduct causal mediation analysis.
Results:
All SH markers, except contact frequency, were associated with lower subsequent depression, but not inflammatory biomarkers. Greater contact frequency (e.g. once-twice a week vs <once per year: β=0.18 [0.01, 0.36]) and less negative support (β=0.02 [0.00, 0.03]) were associated with higher verbal fluency. Larger network size (>6 people vs none: β=0.007SD/year [0.001, 0.012]), less negative (β=0.001SD/year [0.001, 0.002]) and more positive support (β=0.001SD/year [0.000, 0.001]) were linked with slower memory decline, and more positive support predicted slower verbal fluency decline (β=0.001SD/year [0.000, 0.001]). Depression symptoms were associated with lower memory and verbal fluency, and faster memory decline (β=-0.001SD/year [-0.001, -0.000]) and verbal fluency (β=-0.001SD/year [-0.001, -0.000]). CRP was associated with lower verbal fluency (β=-0.02 [-0.04, 0.00]), whereas fibrinogen was linked with faster memory decline (β=-0.001SD/year [-0.003, -0.000]).
Conclusion:
Depression symptoms and SH showed associations with subsequent cognitive capability and change. SH was linked with lower depression, but not inflammatory biomarkers. Findings highlight the potential for depression to underpin associations between SH and cognition, a pathway which we will test using causal mediation analysis. We will also examine whether findings replicate in the Swedish National Study of Aging and Care in Kungsholmen.
The aneutronic 11B(p, α)2α fusion reaction driven by the interaction of high-energy lasers with matter has become a popular topic of research, since it represents a potential long-term goal alternative to the most studied deuterium-tritium reaction. However, the detection of the typical ionic products, especially alpha particles, of this low-rate fusion reaction is a challenging issue, due to their low flux. One of the diagnostic devices that can be implemented in laser-driven proton-boron fusion experiments is a Thomson spectrometer (TS), which is capable of detecting and discriminating ions according to their mass-to-charge ratio (A/Z, where A is the mass number and Z is the atomic number of the ions). In this work, we report on the ultimate test of a TS, which was designed and developed at the ENEA Research Centre in Frascati, Italy, in the context of a p + 11B fusion experiment. Our device—designed to have high sensitivity and a robust shielding against electromagnetic pulses (EMPs)—was implemented at the PALS laser facility (∼700 J in ∼350 ps pulses) at a distance of 367 mm from the laser-plasma interaction point. We analyse here the measured signals obtained with our device, focusing on the assessment of their signal-to-background ratio. Despite the presence of strong EMPs and background radiation at such a short distance from the laser-irradiated target, the TS proved to be suitable for effectively detecting protons and heavier ions stemming from the plasma source.
The energy problem is an open issue becoming increasingly pressing. The possibility to use nuclear fusion as an alternative energy source is thus acquiring progressively more importance and many investors are pushing to achieve the goal of an electric plant based on fusion. The most studied reaction is the deuterium-tritium one, but this poses several technical issues related to the handling of the radioactive fuel and neutron generation. In this frame, the aneutronic 11B(p, α)2α fusion reaction has attracted the interest of many researchers. Despite a fusion reactor based on pB is still a long-term goal, the study of this reaction is important both for astrophysics research and for its possible employment in schemes of high brightness source of α particles for applications, as for instance in medicine. Nevertheless, the univocal identification of the produced alphas is a well-known challenging task when the reaction is triggered by high-intensity lasers. Indeed, due to the multifaceted emission typical of laser-matter interactions, the signal coming from alphas is often superimposed to that generated by protons and by other ions, and in many cases, it is therefore hardly recognizable. In this work, we analysed the possibility of employing a Thomson spectrometer (TS) with an adequate differential filtering system for the exclusion from the α-particle trace, the contribution of all other ionic species. Moreover, for the energy ranges where the filtering method cannot be successfully applied, we investigated the feasibility of integrating in the TS assembly a particle detector for time-of-flight (TOF) measurements.
Although the COVID-19 pandemic has affected depression, evidence of the role of pre-pandemic history of depression remains limited.
Aims
We investigated how long-term trajectories of depressive symptomatology before the COVID-19 pandemic were related to depression during the pandemic, over and above the latest pre-pandemic depression status. Furthermore, we examined whether those experiencing depression closer to the pandemic were at higher risk during the pandemic.
Method
Employing data from waves 4–9 of the English Longitudinal Study of Ageing (2008–2009 to 2018–2019), we used group-based trajectory modelling on 3925 English older adults aged 50+ years to identify distinctive trajectories of elevated depressive symptoms (EDS). Fully adjusted logistic models were then used to examine the associations between trajectories and depression during the COVID-19 pandemic (June–July and November–December 2020).
Results
We identified four classes of pre-pandemic trajectories of EDS. About 5% were classed as ‘enduring EDS’, 8% as ‘increasing EDS’, 10% as ‘decreasing EDS’ and 77% as ‘absence of EDS’. Compared with respondents with absence of EDS, those with EDS history were more likely to have depression during the COVID-19 pandemic, particularly those with enduring or increasing EDS in the previous 10 years. Moreover, the frequency of EDS was more crucial in predicting the risks of depression during the pandemic than the timing of the latest episode.
Conclusions
Trajectories of depressive symptomatology are an important risk factor for older adults’ mental health, particularly in the context of crisis. Older people with enduring or increasing EDS should receive particular attention from policy makers when provisioning post-pandemic well-being support.
Informal care plays an important role in the provision of care. However, previous research has mainly focused on middle- or older-aged informal carers and less is known about informal care among young adults, its consequences on educational achievement and employment transitions and whether this varies across country contexts. Using data from the 2009–2018 waves of the UK Household Longitudinal Study (N = 25,856) and the German Socio-Economic Panel (N = 16,666), we investigated the influence of informal care responsibilities of 17–29 year olds on their chances of achieving a university degree using logistic regression and employment transitions using Cox proportional hazard regression models. Our results revealed that young adulthood caring was negatively associated with the likelihood of obtaining a university degree, reduced the likelihood of entering employment and increased the likelihood of unemployment. These associations were more pronounced if people reported caring for more weekly hours (especially in the UK) or caring for longer durations (especially in Germany). The potential negative influence of caring in young adulthood on education was stronger for women than for men in Germany, and the influence of caring on entering unemployment was stronger for women than for men in the UK.
Different electrophysiological (EEG) indices have been investigated as possible biomarkers of schizophrenia. However, these indices have a very limited use in clinical practice, as their associations with clinical and functional outcomes remain unclear. This study aimed to investigate the associations of multiple EEG markers with clinical variables and functional outcomes in subjects with schizophrenia (SCZs).
Methods
Resting-state EEGs (frequency bands and microstates) and auditory event-related potentials (MMN-P3a and N100-P3b) were recorded in 113 SCZs and 57 healthy controls (HCs) at baseline. Illness- and functioning-related variables were assessed both at baseline and at 4-year follow-up in 61 SCZs. We generated a machine-learning classifier for each EEG parameter (frequency bands, microstates, N100-P300 task, and MMN-P3a task) to identify potential markers discriminating SCZs from HCs, and a global classifier. Associations of the classifiers’ decision scores with illness- and functioning-related variables at baseline and follow-up were then investigated.
Results
The global classifier discriminated SCZs from HCs with an accuracy of 75.4% and its decision scores significantly correlated with negative symptoms, depression, neurocognition, and real-life functioning at 4-year follow-up.
Conclusions
These results suggest that a combination of multiple EEG alterations is associated with poor functional outcomes and its clinical and cognitive determinants in SCZs. These findings need replication, possibly looking at different illness stages in order to implement EEG as a possible tool for the prediction of poor functional outcome.
The flow generated by the breaking of free-surface waves in a periodic domain is simulated numerically with a gas–liquid Navier–Stokes solver. The solver relies on the volume-of-fluid method to account for different phases, and the interface tracking is carried out by using novel schemes based on a tailored total-variation-diminishing limiter. The numerical solver is proved to be characterized by a low numerical dissipation, thanks to the use of a scheme that guarantees energy conservation in the discrete form. Both two- and three-dimensional simulations have been performed, and the analysis is presented in terms of energy dissipation, air entrainment, bubble fragmentation, statistics and distribution. Particular attention is paid to the analysis of the mechanisms of viscous dissipation. To this purpose, coherent vortical structures, such as vortex tubes and vortex sheets, are identified, and the different behaviours of the vortex sheets and tubes at various Reynolds numbers are highlighted. The correlation between vortical structures and energy dissipation demonstrates clearly their close link both in the mixing zone and in the pure water domain, where the coherent structures propagate as a consequence of the downward transport. Notably, it is found that the dissipation is identified primarily by the vortex sheets, whereas the vortex tubes govern mainly the intermittency.
Symptoms of depression are transdiagnostic heterogenous features frequently assessed in psychiatric disorders, that impact the response to first-line treatment and are associated with higher suicide risk. This study assessed whether severe mental pain could characterize a specific phenotype of severely depressed high-risk psychiatric patients. We also aimed to analyze differences in treatments administered.
Methods
2,297 adult patients (1,404 females and 893 males; mean age = 43.25 years, SD = 15.15) treated in several Italian psychiatric departments. Patients were assessed for psychiatric diagnoses, mental pain, symptoms of depression, hopelessness, and suicide risk.
Results
More than 23% of the patients reported high depression symptomatology and high mental pain (HI DEP/HI PAIN). Compared to patients with lower symptoms of depression, HI DEP/HI PAIN is more frequent among females admitted to an inpatient department and is associated with higher hopelessness and suicide risk. In addition, HI DEP/HI PAIN (compared to both patients with lower symptoms of depression and patients with higher symptoms of depression but lower mental pain) were more frequently diagnosed in patients with personality disorders and had different treatments.
Conclusions
Patients reporting severe symptoms of depression and high mental pain presented a mixture of particular dangerousness (high trait hopelessness and the presence of suicide ideation with more frequency and less controllability and previous suicide behaviors). The presence of severe mental pain may act synergically in expressing a clinical phenotype that is likewise treated with a more complex therapeutic regime than that administered to those experiencing symptoms of depression without mental pain.
During the COVID-19 pandemic, older and clinically vulnerable people were instructed to shield or stay at home. Policies restricting social contact and human interaction pose a risk to mental health, but we know very little about the impact of shielding and stay-at-home orders on the mental health of older people.
Aims
To understand the extent to which shielding contributes to poorer mental health.
Method
We used longitudinal data from wave 9 (2018/2019) and two COVID-19 sub-studies (June/July 2020; November/December 2020) of the English Longitudinal Study of Ageing, and constructed logistic and linear regression models to investigate associations between patterns of shielding during the pandemic and mental health, controlling for sociodemographic characteristics, pre-pandemic physical and mental health, and social isolation measures.
Results
By December 2020, 70% of older people were still shielding or staying at home, with 5% shielding throughout the first 9 months of the pandemic. Respondents who shielded experienced worse mental health. Although prior characteristics and lack of social interactions explain some of this association, even controlling for all covariates, those shielding throughout had higher odds of reporting elevated depressive symptoms (odds ratio 1.87, 95% CI 1.22–2.87) and lower quality of life (β = −1.28, 95% CI −2.04 to −0.52) than those who neither shielded nor stayed at home. Shielding was also associated with increased anxiety.
Conclusions
Shielding seems associated with worse mental health among older people, highlighting the need for policy makers to address the mental health needs of those who shielded, both in the current pandemic and for the future.
Many countries have implemented policies to extend working lives in response to population ageing, yet there remains little understanding of what drives paid work in later life, nor how this is changing over time. This paper utilises the 1988/89 Survey of Retirement and Retirement Plans, the 1999 British Household Panel Survey and the 2008 English Longitudinal Study of Ageing, to investigate drivers of paid work in the ten years surrounding state pension age (SPA) for women and men in, comparing cohorts born in the 1920s, 1930s and 1940s. Using optimal matching analysis with logistic and multinomial regression models, the study assesses the relative importance of lifecourse histories, socio-economic circumstances and contemporaneous factors, in determining paid work in mid- and later life. Participation in paid work in the five years preceding and beyond SPA increased markedly for men and women across cohorts, with women's lifecourses and engagement with paid work changing considerably in these periods. However, for women, a lifetime history of paid work remained a crucially important predictor of paid work in later life, and this relationship has strengthened over time. Experiencing divorce has also become an important driver of paid work around SPA for the youngest cohort. Having children later, and still having a mortgage, also independently predict labour force participation for women and men. Across all cohorts and for women and men, working at these older ages was a function of higher income and better health. These findings suggest that policies which enable people to maintain ties to paid work across the lifecourse may be more effective at encouraging later-life employment than those concerned only with postponing the retirement transition.
The time-of-flight technique coupled with semiconductor detectors is a powerful instrument to provide real-time characterization of ions accelerated because of laser–matter interactions. Nevertheless, the presence of strong electromagnetic pulses (EMPs) generated during the interactions can severely hinder its employment. For this reason, the diagnostic system must be designed to have high EMP shielding. Here we present a new advanced prototype of detector, developed at ENEA-Centro Ricerche Frascati (Italy), with a large-area (15 mm × 15 mm) polycrystalline diamond sensor having 150 μm thickness. The tailored detector design and testing ensure high sensitivity and, thanks to the fast temporal response, high-energy resolution of the reconstructed ion spectrum. The detector was offline calibrated and then successfully tested during an experimental campaign carried out at the PHELIX laser facility (${E}_L\sim$ 100 J, ${\tau}_L = 750$ fs, ${I}_L\sim \left(1{-}2.5\right)\times {10}^{19}$ W/cm2) at GSI (Germany). The high rejection to EMP fields was demonstrated and suitable calibrated spectra of the accelerated protons were obtained.
People with severe mental illnesses (SMI) have a mortality rate two times higher compared to the general population, with a decade of years of life lost. In this randomized controlled trial (RCT), we assessed in a sample of people with bipolar disorder, major depressive disorder, and schizophrenia spectrum disorder, the efficacy of an innovative psychosocial group intervention compared to a brief psychoeducational group intervention on patients’ body mass index (BMI), body weight, waist circumference, Framingham and HOMA-IR indexes.
Methods
This is a multicentric RCT with blinded outcome assessments carried out in six Italian university centers. After recruitment patients were randomized to receive a 6-month psychosocial intervention to improve patients’ physical health or a brief psychoeducational intervention. All recruited patients were assessed with standardized assessment instruments at baseline and after 6 months. Anthropometric parameters and blood samples have also been collected.
Results
Four-hundred and two patients with a diagnosis of bipolar disorder (43.3%), schizophrenia or other psychotic disorder (29.9%), or major depression (26.9%) were randomly allocated to the experimental (N = 206) or the control group (N = 195). After 6 months, patients from the experimental group reported a significant reduction in BMI (odds ratio [OR]: 1.93, 95% confidence intervals [CI]: 1.31–2.84; p < 0.001), body weight (OR = 4.78, 95% CI: 0.80–28.27, p < 0.05), and waist circumference (OR = 5.43, 95% CI: 1.45–20.30, p < 0.05). Participants with impaired cognitive and psychosocial functioning had a worse response to the intervention.
Conclusions
The experimental group intervention was effective in improving the physical health in SMI patients. Further studies are needed to evaluate the feasibility of this intervention in real-world settings.
The COVID-19 pandemic has disrupted lives and livelihoods, and people already experiencing mental ill health may have been especially vulnerable.
Aims
Quantify mental health inequalities in disruptions to healthcare, economic activity and housing.
Method
We examined data from 59 482 participants in 12 UK longitudinal studies with data collected before and during the COVID-19 pandemic. Within each study, we estimated the association between psychological distress assessed pre-pandemic and disruptions since the start of the pandemic to healthcare (medication access, procedures or appointments), economic activity (employment, income or working hours) and housing (change of address or household composition). Estimates were pooled across studies.
Results
Across the analysed data-sets, 28% to 77% of participants experienced at least one disruption, with 2.3–33.2% experiencing disruptions in two or more domains. We found 1 s.d. higher pre-pandemic psychological distress was associated with (a) increased odds of any healthcare disruptions (odds ratio (OR) 1.30, 95% CI 1.20–1.40), with fully adjusted odds ratios ranging from 1.24 (95% CI 1.09–1.41) for disruption to procedures to 1.33 (95% CI 1.20–1.49) for disruptions to prescriptions or medication access; (b) loss of employment (odds ratio 1.13, 95% CI 1.06–1.21) and income (OR 1.12, 95% CI 1.06 –1.19), and reductions in working hours/furlough (odds ratio 1.05, 95% CI 1.00–1.09) and (c) increased likelihood of experiencing a disruption in at least two domains (OR 1.25, 95% CI 1.18–1.32) or in one domain (OR 1.11, 95% CI 1.07–1.16), relative to no disruption. There were no associations with housing disruptions (OR 1.00, 95% CI 0.97–1.03).
Conclusions
People experiencing psychological distress pre-pandemic were more likely to experience healthcare and economic disruptions, and clusters of disruptions across multiple domains during the pandemic. Failing to address these disruptions risks further widening mental health inequalities.
Porous materials have many applications for laser–matter interaction experiments related to inertial confinement fusion. Obtaining new knowledge about the properties of the laser-produced plasma of porous media is a challenging task. In this work, we report, for the first time to the best of our knowledge, the time-dependent measurement of the reflected light of a terawatt laser pulse from the laser-produced plasma of low-Z foam material of overcritical density. The experiments have been performed with the ABC laser, with targets constituted by foam of overcritical density and by solid media of the same chemical composition. We implemented in the MULTI-FM code a model for the light reflection to reproduce and interpret the experimental results. Using the simulations together with the experimental results, we indicate a criterion for estimating the homogenization time of the laser-produced plasma, whose measurement is challenging with direct diagnostic techniques and still not achieved.
One in six adolescents suffers from mental health problems. Despite the presence of general information on Italian adolescents' mental health, researches conducted with standardized assessment tools are scarce in the literature. We evaluated the prevalence of self-reported behavioral and emotional problems in a group of Italian adolescents and examined their relation to socio-demographical variables.
Methods
This population-based sampling survey was conducted on high school students aged 14–18 from urban areas of Rome and Latina. Participants completed Youth Self-Report (YSR) and a socio-demographic schedule to collect information on age, gender, type of school attended, socio-economic status, urbanicity.
Results
Final sample consisted of 1400 adolescents (38.61% male, mean age 16 years, s.d. 1.42). Prevalence of Internalizing Problems, Externalizing Problems and Total Problems was 29.55%, 18.34% and 24.13%. In our multivariable model, Internalizing Symptoms were not explained by sociodemographic variables while Externalizing Symptoms were explained by Male Gender [OR = 1.53 (1.14–2.06)], older age [OR = 2.06 (1.52–2.79)] and attending a Technical and Professional Institute [OR = 2.15 (1.53–3.02)], with an adjusted R2 = 4.32%. Total Problems were explained by School Type [Technical and Professional Institutes and Art and Humanities v. Grammar and Science School; OR respectively 1.93 (1.40–2.67) and 1.64 (1.08–2.47)], adjusted R2 = 1.94.
Conclusions
The study provides, for the first time, evidence of a great prevalence of self-reported behavioral and emotional problems in a large sample of Italian adolescents, highlighting the role of different socio-demographic variables as risk factors for externalizing behaviors. Our results emphasize the urgent need for implementing prevention programs on mental health in adolescence.
Rasd2 is a striatal GTP-binding protein that modulates Akt and mTOR signaling cascades, well known to be highly vulnerable pathways in psychiatric disorders.
Aims
We investigated the association of Rasd2 and its genetic variation with a series of prefronto-striatal phenotypes related to psychosis in rodents and humans.
Objectives
We want to provide evidence that Rasd2 controls the vulnerability to schizophrenia-related behavior induced by psychothomimetic drugs in mice. Moreover, we aim to find genetic variations within the Rasd2 gene that influence a series of brain schizophrenia-related phenotypes in human.
Methods
Rasd2 knockout mice were employed to evaluate schizophrenia-like behaviors induced by psychotomimetic drugs like amphetamine and phencyclidine. Furthermore, we investigated if RASD2genetic variations in humans are associated with mRNA expression in post-mortem prefrontal cortex, as well as prefrontal and striatal grey matter volume and physiology during working memory as measured with MRI in healthy subjects. Finally, we assessed RASD2mRNA expression levels in post-mortem brains of patients with schizophrenia and bipolar disorder.
Results
We found that both psychotomimetics triggered greater vulnerability to motor stimulation and to prepulse inhibition deficits in Rasd2 mutants. In humans, we found that a genetic variation (rs6518956) within RASD2 predicts prefrontal mRNA expression as well as prefrontal grey matter volume and prefronto-striatal activity during working memory. Finally, we reported that RASD2 mRNA expression is slightly reduced in post-mortem prefrontal cortex of patients with schizophrenia.
Conclusions
Collectively, our data suggests that RASD2represents a gene of potential interest in psychiatric disorders for its ability to modulate prefronto-striatal phenotypes related to schizophrenia.
According to some studies, 80% of subjects suffering from post-traumatic stress disorder (PTSD) present twice the risk of developing an insanity as they age because of the high level of stress that has been induced. Indeed, the triggered trauma has a deleterious effect on the establishment of the stress’ axis (the hypothalamic pituitary adrenal axis) which is then not able to regulate itself. As a consequence, the hippocampal neurons will be attacked by an excess of cortisol. Memory's dysfunction is central in the symptomatology of PTSD, particularly in respect to encoding and recall. The hippocampus is able to transfer information to the prefrontal cortex. Actually, subjects with PTSD present less activity in the prefrontal cortex triggered by a decrease of encoding and recall capacities. EMDR therapy (eye movement desensitization and recruitment) allow for a fast relief of symptoms by a bilateral alternate stimulation (SBA). Indeed, saccadic eye movements stem affect related to the traumatic event and process the associated cognitions. During the desensitization phase in EMDR, we noticed an increase in activity of the brain's prefrontal, ventromedial, amygdala and thalamic regions. Indeed, the recall of traumatic memories goes through implicit emotional valence regions and associative areas for which the experience is already deeply integrated. After comparing cerebral activity before and after the therapy, researches on EMDR shows that a reduction of stress’ symptoms has some sensitive link to PTSD (in prevention to dementia).
Disclosure of interest
The authors have not supplied their declaration of competing interest.