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Preparatory control in task-switching has been suggested to rely upon a set of distributed regions within a frontoparietal network, with frontal and parietal cortical areas cooperating to implement switch-specific preparation processes. Although recent causal evidence using transcranial magnetic stimulation (TMS) have generally supported this model, alternative results from both functional neuroimaging and neurophysiological studies have questioned the switch-specific role of both frontal and parietal cortices. The aim of the present study was to clarify the involvement of prefrontal and parietal areas in preparatory cognitive control. With this purpose, an fMRI study was conducted to identify the brain areas activated during cue events in a task-switching paradigm, indicating whether to switch or to repeat among numerical tasks. Then, TMS was applied over the specific coordinates previously identified through fMRI, that is, the right inferior frontal gyrus (IFG) and right intraparietal sulcus (IPS). Results revealed that TMS over the right IFG disrupted performance in both switch and repeat trails in terms of delayed responses as compared to Sham condition. In contrast, TMS over the right IPS selectively interfered performance in switch trials. These findings support a multi-component model of executive control with the IFG being involved in more general switch-unspecific process such as the episodic retrieval of goals, and the IPS being related to the implementation of switch-specific preparation mechanisms for activating stimulus-response mappings. The results are discussed within the framework of contemporary hierarchical models of prefrontal cortex organization, suggesting that distinct prefrontal areas may carry out coordinated functions in preparatory control.
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OBJECTIVE: While social cognition is shown to be impaired in several mental disorders, the effects of cannabis on social cognition are still not clear. Past studies have used the multifaceted empathy test (MET) to study social cognition. This study aims to test the validity of the MET Spanish version and to evaluate the effects of cannabis use on social cognition. METHODS: In total 116 participants from a Cannabis Social Club (CSC) completed the MET and the reading the mind in the eyes test (RMET) under the effects of cannabis and were compared to 86 university students (control group). Internal consistency and convergent validity were assessed. Cognitive empathy (CE) and emotional empathy (EE) were tested in both groups. RESULTS: The MET CE scale shows low internal consistency, while the EE scale shows high internal consistency. Items showed similar difficulty for both groups. Cannabis users showed deficient overall emotional recognition, with reduced scores associated with positive stimuli. Overall scores for EE were similar for both groups, but the experimental group scored lower with negative stimuli when compared to controls. CONCLUSION: This study validates the MET Spanish version for its use in future studies. Results confirmed deficient emotional recognition in cannabis users and a dampened reaction to negative stimuli for the first time.
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INTRODUCTION: Ultrasonography (US) in patients with obesity allows us to measure different layers of abdominal fat (superficial subcutaneous, deep subcutaneous, preperitoneal, omental, and perirenal), not assessable by DEXA or CT scan. Omental and perirenal fat depots are considered predictors of metabolic complications. Liraglutide is particularly effective in reducing weight in patients with insulin-resistance, but its direct impact on each abdominal fat layer is unknown. METHODS: We measured, at the L4 level, all 5 abdominal fat depots in 860 patients with obesity (72.8% women, mean age 56.6 ± 1.5 years, BMI 34.4 ± 4.7 kg/m2, body fat 47 ± 2%, abdominal circumference 105.8 ± 3 cm), before and after 6 months of liraglutide treatment. Laboratory tests for glucose, insulin, and lipid profile were routinely done. T-student was used to compare intraindividual differences. RESULTS: Weight loss was 7.5 ± 2.8 kg (7.96% from baseline), with no differences by sex/age/BMI. Greater loss was observed in patients with higher dosages and NAFLD. All US-measured fat layers showed a significant reduction (p < 0.05) at 6th months. Preperitoneal fat showed a -26 ± 5.5% reduction and 46% of the patients went below metabolic syndrome (MS) risk cut-off values. Omental fat was reduced by -17.8 ± 5% (67% of the patients below MS risk) and perirenal fat by -22.4 ± 4.4% (56% of the patients below MS). Both omental and perirenal fat reduction correlated with total and LDL cholesterol. Higher perirenal fat reduction (-28%) was seen among patients with obesity and hypertension. Perirenal fat also correlated with blood pressure reduction. CONCLUSION: Liraglutide induces greater fat loss in the layers involved with MS. However, the maximal reduction is seen at perirenal fat, which has been recently related with hypertension and could play an important role in modulating kidney's expansion and intraglomerular pressure. US is a reproducible clinical tool to assess pathologic fat depots in patients living with obesity.
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Gordura Abdominal , Liraglutida , Obesidade , Ultrassonografia , Humanos , Feminino , Liraglutida/uso terapêutico , Liraglutida/farmacologia , Pessoa de Meia-Idade , Masculino , Ultrassonografia/métodos , Gordura Abdominal/diagnóstico por imagem , Gordura Abdominal/efeitos dos fármacos , Obesidade/diagnóstico por imagem , Redução de Peso/efeitos dos fármacos , Índice de Massa Corporal , Rim/diagnóstico por imagem , Rim/efeitos dos fármacos , Rim/metabolismo , Resistência à Insulina , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/farmacologiaRESUMO
Cannabis is being legalized for medical and recreational purposes all around the world. However, the understanding of the psychological effects of cannabis is still limited, and it has been previously linked to mental disorders such as schizophrenia. Lately, new scales have been created and adapted to measure its psychological effects. The aim of this study is to create Spanish versions of some of these scales and test their psychometric characteristics. One hundred sixteen participants were recruited from Cannabis Social Clubs (CSC) in Barcelona, Spain. Participants under the effects of their own cannabis completed the Cannabis Experience Questionnaire-modified version (CEQ-mv), Addiction Research Centre Inventory-18 (ARCI-18), Psychotomimetic States Inventory (PSI) and Visual Analogue Scales (VAS). Questionnaires were completed in the CSC, providing a naturalistic setting for the study. Exploratory factor analysis and internal consistency were analyzed. PSI was reduced from a 6-factor to a 4-factor model with adequate to low reliability, ARCI-18 was reduced from a 3-factor to a 2-factor model with good reliability, and VAS were reduced from a 4-factor to a 3-factor model, also with good reliability. These questionnaires showed adequate reliability and can be used in future studies to test the subjective effects of cannabis in clinical and naturalistic settings.
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Background: Social cognition abilities such as empathy and the Theory of Mind (ToM) have been shown to be impaired in neuropsychiatric conditions such as psychotic, autistic, and bipolar disorders. The endocannabinoid system (ECS) seems to play a role in social behavior and emotional processing while it also seems to play a role in those neuropsychiatric conditions showing social cognition impairments. Main plant cannabinoids delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) modulate the ECS and, due to their opposite effects, have been proposed as both cause and treatment for neuropsychiatric-related disorders such as schizophrenia, anxiety, or post-traumatic stress disorder (PTSD). The aim of this study was to test the effects of THC and CBD on social cognition abilities in chronic cannabis users. Method: Eighteen members from a cannabis social club were tested for social cognition effects under the effects of different full spectrum cannabis extracts containing either THC, CBD, THC+CBD, or placebo in a naturalistic randomized double-blind crossover placebo-controlled study. Results: Results showed that participants under the effects of THC showed lower cognitive empathy when compared with the effects of CBD but not when those were compared with THC+CBD or placebo. Also, participants showed higher cognitive ToM under the effects of CBD when compared with the effects of placebo, but not when those were compared with THC or THC+CBD. However, we did not find differences on the emotional scales for empathy or ToM. Conclusions: This study provides evidence for the interaction between the effects of THC and CBD and social cognition abilities in a naturalistic environment, which can be of special interest for the clinical practice of medical cannabis on neuropsychiatric disorders. We show for the first time that CBD can improve ToM abilities in chronic cannabis users. Our results might help to understand the role of the ECS in social cognition, and their association with psychiatric and neurodevelopmental disorders such as schizophrenia or autism. Finally, we demonstrate how reliable methodologies can be implemented in naturalistic environments to collect valid ecological evidence outside classic laboratory settings.
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BACKGROUND: Although δ-9-tetrahydrocannabinol (THC), the main cannabinoid from the cannabis plant, is responsible for the psychotomimetic effects of cannabis, cannabidiol (CBD), the second most abundant cannabinoid in the cannabis plant, does not show any psychotomimetic effect. Cannabidiol has even been proposed to be antipsychotic and to counteract some of the psychotomimetic effects of THC. The aim of this study was to test the potential antipsychotomimetic effects of CBD. METHOD: Eighteen members from a cannabis social club were tested for subjective and psychotomimetic effects under the effects of different full-spectrum cannabis extracts containing either THC, CBD, THC + CBD, or placebo in a naturalistic, randomized, double-blind, crossover, placebo-controlled study. RESULTS: Results showed that participants under the effects of THC + CBD showed lower psychotomimetic scores in subjective scales when compared with THC alone. Subjective scores were lower under the effects of CBD and placebo when compared with THC + CBD. Cannabidiol and placebo did not show any psychotomimetic effect. CONCLUSIONS: This study provides evidence for both the psychotomimetic effects of THC and the antipsychotomimetic effects of CBD when it is coadministered with THC in real-world situations, which can be very relevant for the clinical practice of medical cannabis. Ultimately, this study substantiates the link between the endocannabinoid system and psychotic-like symptoms and has important implications for the understanding of schizophrenia and the therapeutic potential of CBD as an antipsychotic. Lastly, we demonstrate how reliable methodologies can be implemented in real situations to collect valid ecological evidence outside classic laboratory settings.
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Canabidiol/farmacologia , Cannabis , Dronabinol/farmacologia , Extratos Vegetais/farmacologia , Psicotrópicos/farmacologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Adulto JovemRESUMO
OBJECTIVE: Abdominal fat ultrasound (US) is a simple clinical tool that may allow measures of fat depots not visible using common dual-energy X-ray absorptiometry (DEXA) or computerized tomography (CT) imaging. The aim of this study was to validate the technique, give measures of superficial and profound subcutaneous, preperitoneal, omental and perirenal (retroperitoneal) fat and correlate them with MS markers. METHODS: Sequential US measures of these five abdominal fat layers were done at 397 adults. Blood pressure (BP), body mass index (BMI), waist, body fat %, HOMA-IR index (homeostatic model assessment of insulin resistance), lipid profile and leptin were recorded. Metabolic syndrome (MS) was defined according to Cholesterol education programme adult treatment panel III (ATPIII) criteria. RESULTS: Subcutaneous and omental fat were increased among people with obesity, whereas preperitoneal and perirenal fat did not show any difference according to BMI or waist. Women showed thicker subcutaneous fat (both superficial and profound), whereas men had bigger omental fat. Both postmenopausal and diabetic patients had changes in omental fat only, whereas patients with fatty liver showed thicker preperitoneal and perirenal fat, as well. MS patients showed both thicker perirenal and omental fat. A cut-off of 54 mm in male (M)/34 mm in female (F) of omental fat and 22.5 mm (M)/12.5 mm (F) of perirenal fat could be predictive of later MS onset. CONCLUSIONS: US is a valid method to measure all different abdominal fat depots. Omental and perirenal fat measures may classify patients at risk for MS. Preperitoneal fat depot may also correlate with fatty liver disease.
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The objective is to present a website designed to improve the quality of life of caregivers of children with cerebral palsy and show data concerning its usefulness. The website was developed in accordance with scientific literature about caregivers' burden. We organized the website around different sections (e.g. family communication, learning to relax) and social support forums. The interactive features of the site were designed to accommodate different caregivers' needs and enable them to choose different pathways according to their own individual needs. Participants were 10 caregivers who took part in a pilot study and completed a questionnaire to analyze the usefulness of the website after five months using it. Preliminary results suggested that the website was useful for participants. The most useful sections were the "peer-to-peer" and the professional forums. This study shows the potential of an online intervention for parents of children with cerebral palsy.
El objetivo del artículo es presentar un sitio web diseñado para mejorar la calidad de vida de cuidadores de niños con parálisis cerebral y mostrar los datos correspondientes a su utilidad. Este sitio fue desarrollado acorde con la literatura científica sobre el tema de carga de los cuidadores y se organizó en torno a diferentes secciones (comunicación familiar, aprender a relajarse, entre otros) y foros de apoyo social. Las características interactivas del sitio fueron diseñadas para satisfacer las necesidades de los cuidadores, eligiendo diferentes caminos en función de las propias. En el estudio piloto participó una muestra de 10 cuidadores que completaron un cuestionario para analizar la utilidad del sitio web después de cinco meses de usarlo. Los resultados preliminares sugieren que este fue útil para los participantes y que las secciones de mayor utilidad fueron la denominada "de par a par" y los foros profesionales. El presente trabajo muestra el potencial de una intervención en línea, para padres de niños con parálisis cerebral.
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Qualidade de Vida , Seguridade SocialRESUMO
AIM: To highlight the effectiveness of transcranial magnetic stimulation (TMS) as therapeutic tool in rehabilitation of neglect. DEVELOPMENT: The therapeutic benefits of TMS in different neurological disorders, such as epilepsy, Parkinson's disease, stroke or dementias, are increasingly evident. For many years clinical research has been conducted to develop new and effective rehabilitation strategies for neglect, being repetitive transcranial stimulation an important tool in this regard. The positive outcomes of treatment of neglect based on noninvasive brain stimulation have been demonstrated by several researchers. So, TMS should be, at least, considered as a therapeutic intervention adjuvant to conventional approaches. CONCLUSIONS: Although the evidence for considering TMS as a new therapeutic tool is still scarce, as therapeutic applications of TMS are a subject of recent study, the findings so far are encouraging. Further research is essential to know the real TMS potential in the rehabilitation of neglect in particular, and of neurological diseases in general.