A public resource of baseline data from the Alzheimer's Prevention Initiative Autosomal-Dominant Alzheimer's Disease Trial.

INTRODUCTION: The Alzheimer's Prevention Initiative Autosomal-Dominant Alzheimer's Disease (API ADAD) Trial evaluated the anti-oligomeric amyloid beta (Aß) antibody therapy crenezumab in cognitively unimpaired members of the Colombian presenilin 1 (PSEN1) E280A kindred. We report availability, methods employed to protect confidentiality and anonymity of participants, and process for requesting and accessing baseline data. METHODS: We developed mechanisms to share baseline data from the API ADAD Trial in consultation with experts and other groups sharing data from Alzheimer's disease (AD) prevention trials, balancing the need to protect anonymity and trial integrity with making data broadly available to accelerate progress in the field. We pressure-tested deliberate and inadvertent potential threats under specific assumptions, employed a system to suppress or mask both direct and indirect identifying variables, limited and firewalled data managers, and put forth specific principles requisite to receive data. RESULTS: Baseline demographic, PSEN1 E280A and apolipoprotein E genotypes, florbetapir and fluorodeoxyglucose positron emission tomography, magnetic resonance imaging, clinical, and cognitive data can now be requested by interested researchers. DISCUSSION: Baseline data are publicly available; treatment data and biological samples, including baseline and treatment-related blood-based biomarker data will become available in accordance with our original trial agreement and subsequently developed Collaboration for Alzheimer's Prevention principles. Sharing of these data will allow exploration of important questions including the differential effects of initiating an investigational AD prevention therapy both before as well as after measurable Aß plaque deposition.

Occurrence, sources, and spatial variation of POPs in a mountainous tropical drinking water supply basin by passive sampling.

Persistent organic pollutants (POPs) are widely distributed along the world and their levels in surface waters may pose a risk to human health due to consumption of contaminated water or fish long-term exposure to contaminated water. The occurrence of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in the Piedras river (Colombia) is a problem of serious concern since freshwater is conducted to a drinking water supply system that provides more than 3 million users. In this research, we deployed silicone rubber membranes as passive samplers in two sampling campaigns at seven sampling stations selected along the river, to assess sources and spatial variation of POPs. The measurements confirmed freely dissolved concentration of the EPA prioritized PAHs (excluding naphthalene), PCBs, heptachlor isomers, dieldrin, endosulfan isomers, among other POPs at trace levels in the water source. The Risk Quotient (RQ) method was applied to prioritize POPs with the highest potential toxicity over aquatic ecosystems. The OCP Heptachlor overcome RQ, while Dieldrin and Endosulfan, and some PAHs congeners such as Perylene, Pyrene, Benzo[a]pyrene, and Fluoranthene displayed medium-risk RQ. Significant differences between sampling stations assessed by One-way ANOVA suggested that the main PAHs and PCBs sources to the river were the punctual discharge from the WWTP and a leachate discharge form a landfill located in the study area. Additionally, nonpoint sources of OCPs were identified. Our results showed that the origin of PAHs and PCBs are associated with urban activities, while the contribution of OCPs is related to the presence of legacy pesticides from past usage in agricultural activities in the basin.

Anosmia como manifestación inicial de COVID-19 en pacientes de hemodiálisis

Contexto Los pacientes en hemodiálisis son una población susceptible para la enfermedad causada por el SARS-CoV-2, enfermedad por el coronavirus 2019 (COVID-19), siendo el diagnóstico temprano una necesidad urgente por considerarse una población de riesgo por presentar cuadros severos y graves. Objetivo Estimar si la anosmia de inicio súbito permite una detección temprana de la infección por COVID-19, en pacientes de hemodiálisis sin síntomas clásicos (que no presentaron malestar general, síntomas respiratorios o gastrointestinales al inicio de la enfermedad). Metodología Se realizó un estudio de prueba diagnóstica durante los meses de septiembre y octubre del 2020 en tres unidades de hemodiálisis en Colombia. Fueron incluidos pacientes adultos, sin síntomas clásicos para COVID-19. Se excluyó a los pacientes con infección previa por COVID-19 o con antecedentes de alteración del olfato. Se recolectaron datos demográficos, clínicos y de laboratorio, previa firma de consentimiento informado avalado por el comité de ética (CEI-487). La anosmia se exploró con una prueba subjetiva para detección de olores antes del inicio de la hemodiálisis. Resultados Se incluyeron 587 pacientes. La prevalencia de anosmia fue de 0,85 % (cinco pacientes) y una incidencia de COVID-19 de 1,19 % (siete pacientes). No hubo diferencia estadística al comparar las variables demográficas, clínicas y de laboratorio entre pacientes con y sin anosmia. La presencia de anosmia tuvo una sensibilidad y un valor predictivo positivo del 0 %, pero una especificidad del 99,14 % y un valor predictivo negativo del 98,8 %. La exactitud fue del 97,9 %. Conclusiones La prevalencia de anosmia en nuestra población de hemodiálisis fue baja. Se debería indagar en el triaje cualquier síntoma (incluida la alteración del sentido del olfato) como estrategia para detectar de forma temprana casos individuales de COVID-19 o un brote en las unidades de hemodiálisis.

Background Hemodialysis patients are susceptible population for COVID-19 the disease caused by SARS-CoV-2, with early diagnosis being an urgent and needed because they are considered a population with high risk for severe and serious conditions. Purpose The objective of our study was to estimate whether sudden-onset anosmia allow to detect COVID-19 infection early in hemodialysis patients without classic symptoms (who did not present malaise, respiratory or gastrointestinal symptoms at the beginning of the disease). Methodology A diagnostic test study was accomplished during the months of September and October 2020 in three hemodialysis units in Colombia. Adult patients without classic symptoms for COVID-19 were included. Patients with previous COVID-19 infection or with a history of smell alteration were excluded. Demographic, clinical, and laboratory data were collected, prior signature of informed consent endorsed by the ethics committee. Anosmia was evaluated with objective test for odor detection before the start of hemodialysis session. Results 587 patients were included. Anosmia prevalence was 0.85% (5 patients) and the incidence of COVID-19 was 1.19% (7 patients). There was no statistically difference in demographic, clinical, and laboratory comparison between patients with and without anosmia. The presence of anosmia had a sensitivity and a positive predictive value of 0%, but a specificity of 99.14% and a negative predictive value of 98.8%. The accuracy was 97.9%. Conclusions The prevalence of anosmia in our hemodialysis population was low. Any symptoms (including altered sense of smell) should be investigated in TRIAGE as a strategy to detect early individual cases of COVID-19 or an outbreak in hemodialysis units.

Sex differences in cognitive resilience in preclinical autosomal-dominant Alzheimer's disease carriers and non-carriers: Baseline findings from the API ADAD Colombia Trial.

INTRODUCTION: Females may have greater susceptibility to Alzheimer's disease (AD)-pathology. We examined the effect of sex on pathology, neurodegeneration, and memory in cognitively-unimpaired Presenilin-1 (PSEN1) E280A mutation carriers and non-carriers. METHODS: We analyzed baseline data from 167 mutation carriers and 75 non-carriers (ages 30 to 53) from the Alzheimer's Prevention Initiative Autosomal Dominant AD Trial, including florbetapir- and fludeoxyglucose-PET, MRI based hippocampal volume and cognitive testing. RESULTS: Females exhibited better delayed recall than males, controlling for age, precuneus glucose metabolism, and mutation status, although the effect was not significant among PSEN1 mutation carriers only. APOE ε4 did not modify the effect of sex on AD biomarkers and memory. DISCUSSION: Our findings suggest that, among cognitively-unimpaired individuals at genetic risk for autosomal-dominant AD, females may have greater cognitive resilience to AD pathology and neurodegeneration than males. Further investigation of sex-specific differences in autosomal-dominant AD is key to elucidating mechanisms of AD risk and resilience.

Baseline demographic, clinical, and cognitive characteristics of the Alzheimer's Prevention Initiative (API) Autosomal-Dominant Alzheimer's Disease Colombia Trial.

INTRODUCTION: The API AutosomalDominant AD (ADAD) Colombia Trial is a placebo-controlled clinical trial of crenezumab in 252 cognitively unimpaired 30 to 60-year-old Presenilin 1 (PSEN1) E280A kindred members, including mutation carriers randomized to active treatment or placebo and non-carriers who receive placebo. METHODS: Of the 252 enrolled, we present data on a total of 242 mutation carriers and non-carriers matched by age range, excluding data on 10 participants to protect participant confidentiality, genetic status, and trial integrity. RESULTS: We summarize demographic, clinical, cognitive, and behavioral data from 167 mutation carriers and 75 non-carriers, 30 to 53 years of age. Carriers were significantly younger than non-carriers ((mean age ± SD) 37 ± 5 vs 42 ± 6), had significantly lower Mini Mental Status Exam (MMSE) scores (28.8 ± 1.4 vs 29.2 ± 1.0), and had consistently lower memory scores. DISCUSSION: Although PSEN1 E280A mutation carriers in the Trial are cognitively unimpaired, they have slightly lower MMSE and memory scores than non-carriers. Their demographic characteristics are representative of the local population.

The Alzheimer's Prevention Initiative Autosomal-Dominant Alzheimer's Disease Trial: A study of crenezumab versus placebo in preclinical PSEN1 E280A mutation carriers to evaluate efficacy and safety in the treatment of autosomal-dominant Alzheimer's disease, including a placebo-treated noncarrier cohort.

INTRODUCTION: Autosomal-dominant Alzheimer's disease (ADAD) represents a crucial population for identifying prevention strategies that might modify disease course for cognitively unimpaired individuals at high imminent risk for developing symptoms due to Alzheimer's disease (AD), that is, who have "preclinical" AD. Crenezumab is an antiamyloid monoclonal antibody that binds monomeric and aggregated forms of amyloid ß, with highest affinity for oligomers; it is in development for early stages of sporadic AD and for ADAD. METHODS: This is a prospective, randomized, double-blind, placebo-controlled phase 2 study of the efficacy of crenezumab versus placebo in asymptomatic PSEN1 E280A mutation carriers from family kindreds with ADAD in Colombia. Participants were randomized to receive either crenezumab or placebo for 260 weeks. The study was designed to enroll a planned total of 300 participants, including 200 preclinical mutation carriers (approximately 100 treatment, 100 placebo) and an additional control group of mutation noncarriers from the same family kindreds included to mask mutation carrier status (100 placebo only). The primary outcome is change in the Alzheimer's Prevention Initiative ADAD Composite Cognitive Test Score from baseline to week 260. Secondary outcomes include time to progression to mild cognitive impairment due to AD or dementia due to AD; changes in dementia severity, memory, and overall neurocognitive functioning; and changes in amyloid-positron emission tomography, fluorodeoxyglucose-positron emission tomography, magnetic resonance imaging volumes, and cerebrospinal fluid levels of ß amyloid, tau, and p-tau. Safety and tolerability are assessed. RESULTS: Two hundred fifty-two participants were enrolled between December 2013 and February 2017. DISCUSSION: We describe the first large-scale, potentially label-enabling clinical trial of a preclinical treatment for ADAD. Results from this trial will inform on the efficacy of crenezumab for delaying onset of, slowing decline in, or preventing cognitive impairment in individuals with preclinical ADAD and will foster an improved understanding of AD biomarkers and their relationship to clinical outcomes.

Cambios en el EEG en reposo de exparticipantes en el conflicto armado colombiano con trastorno de personalidad antisocial / Changes in Resting EEG in Colombian Ex-combatants ith Antisocial Personality Disorder

RESUMEN Introducción: El conflicto armado colombiano, además de secuelas sociales y económicas en la población civil, ha implicado otras consecuencias. Los excombatientes, como la otra cara del conflicto, han sido objeto de interrogación sobre su estructura de personalidad y predisposición a conductas violentas. Se ha encontrado en parte de la población asociada al conflicto armado rasgos característicos del trastorno de personalidad antisocial (TPA) que se relacionarían con los comportamientos en contra de las convenciones sociales. Métodos: Mediante registros electrocardiográficos cuantitativos (qEEG), se evaluaron las diferencias en los patrones de actividad cortical entre un grupo de excombatientes, algunos de ellos con diagnóstico de TPA, y un grupo de control ajeno al conflicto armado y sin alteraciones psiquiátricas. Se empleó la Lista de Chequeo de Psicopatía Revisada (PCL-R) para determinar la presencia de criterios diagnósticos de TPA, así como la entrevista diagnóstica para estudios genéticos (DIGS) para clasificar la presencia de otros trastornos mentales incluidos en el CIE-10. Resultados: Se encontraron diferencias significativas en los niveles de psicopatía evaluados mediante la PCL-R. Con respecto al análisis de la potencia espectral, se observaron diferencias entre grupos en las ondas alfa-2 y beta, en regiones frontal y temporal izquierda y temporocentral izquierda respectivamente. Conclusiones: La técnica de qEEG permite evidenciarlas diferencias entre grupos en el potencial espectral en reposo, las cuales se relacionan con comportamientos desadaptativos característicos del TPA.

ABSTRACT Introduction: Although the social and economic consequences of Colombian internal conflicts mainly affected the civilian population, they also had other implications. The ex-combatants, the other side of the conflict, have been the subject of many studies that question their personality structures and antisocial features. Results suggest that ex-combatants usually have characteristics of an antisocial personality disorder (ASPD) that is related with their behavior. Methods: Quantitative EEG (qEEG) was used to evaluate differences in cortical activity patterns between an ex-combatants group and a control group. The Psychopathy Checklist-Revised (PCL-R) was used to assess the presence of ASPD in the ex-combatants group, as well as the Diagnostic Interview for Genetic Studies (DIGS) for other mental disorders classified in the DCI-10. Results: There are significant differences in psychopathy levels between groups, as well as in alpha-2 and beta waves, especially in left temporal and frontal areas for alpha-2 waves and left temporal-central regions for beta waves. Conclusions: qEEG measurements allow spectral resting potential to be differentiated between groups that are related with features typically involved in antisocial personality disorder, and to correlate them with patterns in the questionnaires and clinical interview.

Changes in Resting EEG in Colombian Ex-combatants ith Antisocial Personality Disorder. / Cambios en el EEG en reposo de exparticipantes en el conflicto armado colombiano con trastorno de personalidad antisocial.

INTRODUCTION: Although the social and economic consequences of Colombian internal conflicts mainly affected the civilian population, they also had other implications. The ex-combatants, the other side of the conflict, have been the subject of many studies that question their personality structures and antisocial features. Results suggest that ex-combatants usually have characteristics of an antisocial personality disorder (ASPD) that is related with their behaviour. METHODS: Quantitative EEG (qEEG) was used to evaluate differences in cortical activity patterns between an ex-combatants group and a control group. The Psychopathy Checklist-Revised (PCL-R) was used to assess the presence of ASPD in the ex-combatants group, as well as the Diagnostic Interview for Genetic Studies (DIGS) for other mental disorders classified in the DCI-10. RESULTS: There are significant differences in psychopathy levels between groups, as well as in alpha-2 and beta waves, especially in left temporal and frontal areas for alpha-2 waves and left temporal-central regions for beta waves. CONCLUSIONS: qEEG measurements allow spectral resting potential to be differentiated between groups that are related with features typically involved in antisocial personality disorder, and to correlate them with patterns in the questionnaires and clinical interview.

Precuneus Failures in Subjects of the PSEN1 E280A Family at Risk of Developing Alzheimer's Disease Detected Using Quantitative Electroencephalography.

BACKGROUND: Presenilin-1 (PSEN1) mutations are the most common cause of familial early onset Alzheimer's disease (AD). The PSEN1 E280A (E280A) mutation has an autosomal dominant inheritance and is involved in the production of amyloid-ß. The largest family group of carriers with E280A mutation is found in Antioquia, Colombia. The study of mutation carriers provides a unique opportunity to identify brain changes in stages previous to AD. Electroencephalography (EEG) is a low cost and minimally invasiveness technique that enables the following of brain changes in AD. OBJECTIVE: To examine how previous reported differences in EEG for Theta and Alpha-2 rhythms in E280A subjects are related to specific regions in cortex and could be tracked across different ages. METHODS: EEG signals were acquired during resting state from non-carriers and carriers, asymptomatic and symptomatic subjects from E280A kindred from Antioquia, Colombia. Independent component analysis (ICA) and inverse solution methods were used to locate brain regions related to differences in Theta and Alpha-2 bands. RESULTS: ICA identified two components, mainly related to the Precuneus, where the differences in Theta and Alpha-2 exist simultaneously at asymptomatic and symptomatic stages. When the ratio between Theta and Alpha-2 is used, significant correlations exist with age and a composite cognitive scale. CONCLUSION: Theta and Alpha-2 rhythms are altered in E280A subjects. The alterations are possible to track at Precuneus regions using EEG, ICA, and inverse solution methods.

Successful Object Encoding Induces Increased Directed Connectivity in Presymptomatic Early-Onset Alzheimer's Disease.

BACKGROUND: Recent studies report increases in neural activity in brain regions critical to episodic memory at preclinical stages of Alzheimer's disease (AD). Although electroencephalography (EEG) is widely used in AD studies, given its non-invasiveness and low cost, there is a need to translate the findings in other neuroimaging methods to EEG. OBJECTIVE: To examine how the previous findings using functional magnetic resonance imaging (fMRI) at preclinical stage in presenilin-1 E280A mutation carriers could be assessed and extended, using EEG and a connectivity approach. METHODS: EEG signals were acquired during resting and encoding in 30 normal cognitive young subjects, from an autosomal dominant early-onset AD kindred from Antioquia, Colombia. Regions of the brain previously reported as hyperactive were used for connectivity analysis. RESULTS: Mutation carriers exhibited increasing connectivity at analyzed regions. Among them, the right precuneus exhibited the highest changes in connectivity. CONCLUSION: Increased connectivity in hyperactive cerebral regions is seen in individuals, genetically-determined to develop AD, at preclinical stage. The use of a connectivity approach and a widely available neuroimaging technique opens the possibility to increase the use of EEG in early detection of preclinical AD.

Mutations modifying sporadic Alzheimer's disease age of onset.

The identification of mutations modifying the age of onset (AOO) in Alzheimer's disease (AD) is crucial for understanding the natural history of AD and, therefore, for early interventions. Patients with sporadic AD (sAD) from a genetic isolate in the extremes of the AOO distribution were whole-exome genotyped. Single- and multi-locus linear mixed-effects models were used to identify functional variants modifying AOO. A posteriori enrichment and bioinformatic analyses were applied to evaluate the non-random clustering of the associate variants to physiopathological pathways involved in AD. We identified more than 20 pathogenic, genome-wide statistically significant mutations of major modifier effect on the AOO. These variants are harbored in genes implicated in neuron apoptosis, neurogenesis, inflammatory processes linked to AD, oligodendrocyte differentiation, and memory processes. This set of new genes harboring these mutations could be of importance for prediction, follow-up and eventually as therapeutical targets of AD. © 2016 Wiley Periodicals, Inc.

A Mutation in DAOA Modifies the Age of Onset in PSEN1 E280A Alzheimer's Disease.

We previously reported age of onset (AOO) modifier genes in the world's largest pedigree segregating early-onset Alzheimer's disease (AD), caused by the p.Glu280Ala (E280A) mutation in the PSEN1 gene. Here we report the results of a targeted analysis of functional exonic variants in those AOO modifier genes in sixty individuals with PSEN1 E280A AD who were whole-exome genotyped for ~250,000 variants. Standard quality control, filtering, and annotation for functional variants were applied, and common functional variants located in those previously reported as AOO modifier loci were selected. Multiloci linear mixed-effects models were used to test the association between these variants and AOO. An exonic missense mutation in the G72 (DAOA) gene (rs2391191, P = 1.94 × 10(-4), P FDR = 9.34 × 10(-3)) was found to modify AOO in PSEN1 E280A AD. Nominal associations of missense mutations in the CLUAP1 (rs9790, P = 7.63 × 10(-3), P FDR = 0.1832) and EXOC2 (rs17136239, P = 0.0325, P FDR = 0.391) genes were also found. Previous studies have linked polymorphisms in the DAOA gene with the occurrence of neuropsychiatric symptoms such as depression, apathy, aggression, delusions, hallucinations, and psychosis in AD. Our findings strongly suggest that this new conspicuous functional AOO modifier within the G72 (DAOA) gene could be pivotal for understanding the genetic basis of AD.

[Psychiatric, Cognitive and Emotional Profile in Ex-combatants of Illegal Armed Groups in Colombia]. / Perfil psiquiátrico, cognitivo y de reconocimiento de características emocionales de un grupo de excombatientes de los grupos armados ilegales en Colombia.

INTRODUCTION: Exposure to armed conflict produces biological adaptations oriented to handle the highly stressful conditions in war environments. The special features of The Colombian armed create a special scenario to evaluate the human behavior. OBJECTIVE: In this study, psychiatric, cognitive and emotional processing characteristics of a group of Colombian armed illegal forces of ex-combatants are described. METHODS: Sixty-three ex combatants and 22 controls were assessed with WAIS (IQ), INECO frontal screening (executive functions), Interpersonal Reactivity Index (empathy), emotional features recognition and MINI (psychiatric profile). RESULTS: When compared to the control group, ex-combatants showed higher frequency of antisocial personality disorder (P=.031) and behavioral dissocial disorder (P=.017). In cognitive profile, the ex-combatants showed a lower score in the executive function test (Me=18.50; RQ=4.00), control (Me=23.00; RQ=5.25), with a poor personal distress in emphatic profile (Me=10.00; RQ=5.00) compared to control group (Me=37.00; RQ=7.25). CONCLUSIONS: We found differences in cognitive and psychiatric profile in ex-combatants in comparison with controls.

Perfil psiquiátrico, cognitivo y de reconocimiento de características emocionales de un grupo de excombatientes de los grupos armados ilegales en Colombia / Psychiatric, Cognitive and Emotional Profile in Ex-combatants of Illegal Armed Groups in Colombia

Introducción: La exposición al conflicto armado produce adaptaciones biológicas y psicológicas orientadas a hacer frente al entorno de guerra. Las condiciones particulares del conflicto colombiano hacen un escenario especial en la exploración del comportamiento humano posterior a la exposición al combate. Objetivo: Describir las características psiquiátricas, cognitivas y del procesamiento emocional de un grupo de excombatientes del conflicto armado colombiano. Métodos: Se evaluó a 63 excombatientes y 22 controles en diferentes dominios a través del WAIS (coeficiente intelectual), el INECO Frontal Screening (función ejecutiva), el Interpersonal Reactivity Index (empatía), el reconocimiento de características emocionales y la MINI (perfil psiquiátrico). Resultados: En comparación con los controles, los excombatientes mostraban con mayor frecuencia trastorno de personalidad antisocial (p = 0,031) y trastorno disocial de la conducta (p = 0,017). En el dominio cognitivo, se evidenció peor desempeño en la función ejecutiva de los excombatientes (Me = 18,50; RQ = 4,00) que entre los controles (Me = 23,00; RQ = 5,25), acompanado de un pobre distrés personal en el componente empático (Me = 10,00; RQ = 5,00) respecto al grupo control (Me = 37,00; RQ = 7,25). Conclusiones: Las diferencias en función ejecutiva, distrés personal y perfil psiquiátrico de los excombatientes podrían estar asociadas a los comportamientos adaptativos de los individuos en el entorno de guerra.

Introduction: Exposure to armed conflict produces biological adaptations oriented to handle the highly stressful conditions in war environments. The special features of The Colombian armed create a special scenario to evaluate the human behavior. Objective: In this study, psychiatric, cognitive and emotional processing characteristics of a group of Colombian armed illegal forces of excombatants are described. Methods: Sixty-three ex combatants and 22 controls were assessed with WAIS (IQ), INECO frontal screening (executive functions), Interpersonal Reactivity Index (empathy), emotional features recognition and MINI (psychiatric profile). Results: When compared to the control group, ex-combatants showed higher frequency of antisocial personality disorder (P=.031) and behavioral dissocial disorder (P=.017). In cognitive profile, the ex-combatants showed a lower score in the executive function test (Me = 18.50; RQ=4.00), control (Me = 23.00; RQ=5.25), with a poor personal distress in emphatic profile (Me = 10.00; RQ= 5.00) compared to control group (Me = 37.00; RQ= 7.25). Conclusions: We found differences in cognitive and psychiatric profile in ex-combatants in comparison with controls.

Stop Saying That It Is Wrong! Psychophysiological, Cognitive, and Metacognitive Markers of Children's Sensitivity to Punishment.

Neurodevelopmental evidence suggests that children's main decision-making strategy is to avoid options likely to induce punishment. However, the cognitive and affective factors contributing to children's avoidance to high punishment frequency remain unknown. The present study explored psychophysiological, cognitive, and metacognitive processes associated with sensitivity to punishment frequency. We evaluated 54 participants (between 8 and 15 years old) with a modified Iowa Gambling Task for children (IGT-C) which included options with varying long-term profit and punishment frequencies. Skin conductance responses (SCRs) were recorded during this task. Additionally, we assessed IGT-C metacognitive knowledge, fluid intelligence, and executive functions. Participants exhibited behavioral avoidance and high anticipatory SCRs to options with high frequency of punishment. Moreover, age, IGT-C metacognitive knowledge, and inhibitory control were associated with individual differences in sensitivity to punishment frequency. Our results suggest that children's preference for infrequently punished decisions is partially explained by psychophysiological signals as well as task complexity and development of cognitive control.

Neurophysiological correlates in Mild Cognitive Impairment detected using group Independent Component Analysis.

Alzheimer's disease is the most prevalent cause of dementia. Mild Cognitive Impairment (MCI) is defined as a grey area between intact cognitive functioning and clinical dementia. Electroencephalography (EEG) has been used to identify biomarkers in dementia. Currently, there is a great interest in translating the study from raw signals to signal generators, trying to keep the relationship with neurophysiology. In the current study, EEG recordings during an encoding task were acquired in MCI subjects and healthy controls. Data was decomposed using group Independent Component Analysis (gICA) and the most neuronal components were analyzed using Phase Intertrial Coherence (PIC) and Phase shift Intertrial Coherence (PsIC). MCI subjects exhibited an increase of PIC in the theta band, while controls showed increase in PsIC in the alpha band. Correlation between PIC and PsIC and clinical scales were also found. Those findings indicate that the methodology proposed based in gICA can help to extract information from EEG recordings with neurophysiological meaning.

Emotional processing in Colombian ex-combatants and its relationship with empathy and executive functions.

In this work, the neural correlates of emotional processing in Colombian ex-combatants with different empathy profiles were compared to normal controls matched for age, gender and educational level. Forty ex-combatants and 20 non ex-combatants were recruited for this study. Empathy levels as well as executive functions were measured. Empathy level was used to create three groups. Group 1 (G1) included ex-combatants with normal empathy scores, and Group 2 included ex-combatants with low scores on at least one empathy sub-scales. In control group (Ctrl), participants with no antecedents of being combatants and with normal scores in empathy were included. Age, gender, educational and intelligence quotients level were controlled among groups. event-related potentials (ERPs) were recorded while individuals performed an affective picture processing task that included positive, neutral and negative emotional stimuli, which elicit an early modulation of emotion categorization (Early Posterior Negativity (EPN)) and late evaluative process (LPP). EPN differences were found among affective categories, but no group effects were observed at this component. LPP showed a main effect of category and group (higher amplitudes in ex-combatants). There was an inverse correlation between empathy and executive functions scores and ERPs. Results are discussed according to the impact of emotional processing on empathy profile.

Quantitative EEG analysis disease during resting and memory task in carriers and non-carriers of PS-1 E280A mutation of familial Alzheimer's / Análisis del EEG cuantitativo durante tareas de memoria y reposo en portadores y no portadores de la mutación PS-1 E280A de la enfermedad de Alzheimer

ABSTRACT Background: Alzheimer's disease is the most leading cause of dementia in the world; the mutation PS-1 E280A alters the gene of the Presenilin-1 and causes an early onset familial Alzheimer's disease. This mutation has been found in large kindred of Antioquia, Colombia. The objective of this study was to find differences revealed by electroencephalogram between healthy subjects and asymptomatic carriers that can be used as clinical markers of the disease in this population. Methods: EEG was recorded in 15 asymptomatic E280A carriers and 15 healthy non carriers during resting and a memory task using 64 channels amplifier. Two conditions in the memory task were analyzed: encoding and retrieval, the process of recording and evocating information, respectively. Power spectrum was calculated in delta (0. 5-4. 0 Hz), theta (4. 0-8. 0 Hz), alpha-1 (8. 0-10. 0 Hz), alpha-2 (10. 0-13. 0 Hz), beta (13. 0-25. 0 Hz) and gamma (25. 0-50 Hz) frequency bands for four regions of interest. Changes were evaluated in different conditions by ANOVA analysis.. Results: In resting condition a significant decrease was found in theta (p=0. 0001) and an increase in alpha-2 frequencies (p=0.037) in carriers compare with controls. During encoding of the memory task theta was significantly lower in carriers compared with controls (p=0. 008) and comparing resting versus retrieval process for each group, there was more theta synchronization in carriers. Conclusions: Early changes in theta frequencies were observed in the EEG recordings, it could be use as clinical markers in this population. Also it seems carriers activate additional cortical regions in order to conserve successful cognitive functions before clinical impairment.

RESUMEN Introducción: la enfermedad de Alzheimer es la principal causa de demencia en el mundo; la mutación PS-1 E280A altera el gen presenilin-1 y causa una variante familiar de la enfermedad que se caracteriza por una aparición temprana. La mutación se ha descubierto en un grupo de familias de Antioquia, Colombia. El objetivo de este estudio fue encontrar diferencias, a partir de registros electroencefalográficos de personas portadores de la mutación en una etapa asintomática y sujetos sanos para evaluar si pueden ser utilizadas como un marcador temprano de la enfermedad en la población portadora de la mutación. Metodología: se realizaron registros EEG en 15 portadores asintomáticos de la mutación E280A y 15 personas sanas no portadoras durante una tarea de memoria y en reposo utilizando un amplificador de 64 canales. En la tarea de memoria se evaluaron dos condiciones: codificación y evocación; el proceso de memorizar y recuperar la información, respectivamente. La potencia espectral fue calculada en las bandas de frecuencia delta (0,5-4,0 Hz), teta (4,0-8,0 Hz), alfa-1 (8,0-10,0 Hz), alfa-2 (10,0-13,0 Hz), beta (13,0-25,0 Hz) y gamma (25,0-50 Hz) para cuatro regiones de interés. Los cambios del espectro fueron evaluados por análisis de varianza ANOVA. Resultados: bajo la condición de reposo se encontró una disminución importante en la potencia de la banda teta (p=0,0001) y un incremento en la banda alfa-2 (p=0,037) en portadores comparados con controles. Durante la tarea de codificación, los portadores mostraron una disminución significativa en la banda teta (p=0,008). Al comparar reposo contra memoria de evocación se encontró una mayor sincronización en teta en los portadores de la mutación. Conclusión: se encontraron cambios tempranos de la potencia en la banda teta que pueden ser utilizados como un marcador clínico de la enfermedad en esta población. Una hipótesis adicional basada en los resultados es que los portadores necesitan ...

Dimensiones de la empatía en excombatientes del conflicto armado Colombiano utilizando una escala estandarizada / Dimensions of empathy in ex-combatants of the Colombian armed conflict using a standardized scale

Introducción: La empatía es uno de los constructos de la llamadas neurociencias sociales. Se define como una disposición de dimensiones múltiples que permite colocarse en el estado emocional del otro. Colombia presenta un conflicto interno irregular prolongado, que ha venido deteriorándose en crueldad. Objetivos: Evaluar las dimensiones de la empatía de 285 excombatientes del conflicto armado colombiano, usando el Índice de Reactividad Interpersonal (IRI) en español. Métodos y sujetos: Se seleccionó una muestra de 285 excombatientes, 241 (84,6 %) hombres: 85,3 % paramilitares y 14,7 % guerrilleros. Se les aplicó el IRI de 28 ítems. Se realizaron 3 análisis de factores exploratorios (AFE) y análisis factoriales confirmatorios (AFC), utilizando ecuaciones estructurales. Resultados: Un primer AFE obtuvo 9 factores (KMO = 0,74 y 54,7 % de varianza, consistencia interna [CI]: 0,22-0,63). Un segundo AFE con 20 ítems con cargas superiores a 0,4 mostró una estructura de 6 factores (KMO = 0,70, 50,3 % de varianza; CI: 0,37-0,63). Un tercer AFE forzó las 4 dimensiones originales (KMO = 0,74, varianza 33,77 % y CI: 0,44-0,77). El AFC mostró índices de bondad de ajuste adecuados para los 3 modelos. El de 4 factores obtuvo los más bajos, y el de 6 factores, los más altos. El modelo de 4 factores obtuvo la mejor CI. Conclusión: El IRI en español en excombatientes del conflicto Colombiano tiene estructuras posibles de 4, 6 y 9 factores. El mejor ajuste es la de 6 factores. La de 4 factores tuvo mejor CI.

Introduction: Empathy is one of the main concepts of in social neurosciences. It is defined as a trait with multiple dimensions allowing individuals to place themselves in the emotional states of others. Colombia has an irregular, internal and long-lasting armed conflict which has been increasing its cruelty levels. Objectives: to assess the empathy dimensions of 285 ex-combatants from the internal Colombian conflict, using the Interpersonal Reactivity Index(IRI) in Spanish. Methodology and Subjects: a sample of 285 male ex-combatants, 241 (84, 6%) males: 85,3% paramilitaries, and 14,7% guerillas. The 28 Item IRI questionnaires were administered. 3 exploratory factor analyses (EFA) were performed. Confirmatory factor analyses (CFA) were developed using structural equation procedures. Results: The first EFA obtained 9 factors (KMO=0,74, variance 54,7% and internal consistency (IC): 0,22 - 0,63). The second EFA produced 20 items with burdens above 0,4 and showed a 6-factor structure (KMO=0,70, variance 50,3%, IC: 0,37 - 0,63). The third EFA forced the 4 original IRI dimensions (KMO=0,74, variance 33,77, IC: 0,44 - 0,77. CFAs showed goodness of adjustment indexes adequate for the three models. The 4-factor model obtained the lowest value, while the 6-factor model obtained the highest. The 4- factor model showed the best IC. Conclusion: The Spanish IRI administered to ex-combatants of the Colombian conflict has possible structures of 4, 6 and 9 factors. The best adjustment was for the 6-fctor. The 4-factor model exhibited the best IC.