Clinical and Functional Connectivity Outcomes of 5-Hz Repetitive Transcranial Magnetic Stimulation as an Add-on Treatment in Cocaine Use Disorder: A Double-Blind Randomized Controlled Trial.

BACKGROUND: Cocaine use disorder (CUD) is a global condition lacking effective treatment. Repetitive transcranial magnetic stimulation (rTMS) may reduce craving and frequency of cocaine use, but little is known about its efficacy and neural effects. We sought to elucidate short- and long-term clinical benefits of 5-Hz rTMS as an add-on to standard treatment in patients with CUD and discern underlying functional connectivity effects using magnetic resonance imaging. METHODS: A total of 44 patients with CUD were randomly assigned to complete the 2-week double-blind randomized controlled trial (acute phase) (sham [n = 20, 2 female] and active [n = 24, 4 female]), in which they received two daily sessions of rTMS on the left dorsolateral prefrontal cortex (PFC). Subsequently, 20 patients with CUD continued to an open-label maintenance phase for 6 months (two weekly sessions for up to 6 mo). RESULTS: rTMS plus standard treatment for 2 weeks significantly reduced craving (baseline: 3.9 ± 3.6; 2 weeks: 1.5 ± 2.4, p = .013, d = 0.77) and impulsivity (baseline: 64.8 ± 16.8; 2 weeks: 53.1 ± 17.4, p = .011, d = 0.79) in the active group. We also found increased functional connectivity between the left dorsolateral PFC and ventromedial PFC and between the ventromedial PFC and right angular gyrus. Clinical and functional connectivity effects were maintained for 3 months, but they dissipated by 6 months. We did not observe reduction in positive results for cocaine in urine; however, self-reported frequency and grams consumed for 6 months were reduced. CONCLUSIONS: With this randomized controlled trial, we show that 5-Hz rTMS has potential promise as an adjunctive treatment for CUD and merits further research.

Cognitive and clinic profile of volatile substance users / Perfil cognitivo y clínico de usuarios de sustancias volátiles

Abstract Introduction Inhalant use disorder has increased in spite of its adverse medical consequences. Due to the inherent difficulties of working with this population, so far there has been no quantifiable clinical evidence of the cognitive characteristics of inhalants users in early withdrawal and the clinic effect of consumption time. Objective To evaluate the clinical and cognitive performance of inhalant users and the clinic effects of consumption time. Method A cross-sectional study in which 28 adult users of inhalants were included, divided in two groups according to their consumption time: less than or greater than seven years. They were all evaluated in terms of clinical and neuropsychological values. Results Consumers of inhalant showed presence of craving (M = 479.14, SD = 213.51), altered frontal behavior before (M = 119.18, SD = 29.53) and now (M = 130, SD = 33.03), sleeping problems (M = 8.93, SD = 3.4), and cognitive difficulties (inhibitory control, planning, decision-making, working memory, verbal fluency, and cognitive flexibility); all these tasks were statistically significant (p = < .05). Discussion and conclusion Executive functioning is impaired with inhalant use disorder; these alterations increase with withdrawal and craving and changes remain independent from the use time.

Resumen Introducción El trastorno por uso de inhalables ha aumentado a pesar de las consecuencias médicas adversas. Debido a las dificultades que entraña trabajar con estas poblaciones, hasta hace poco no había evidencia clínica cuantificable de las características cognitivas de los usuarios de inhalables en la abstinencia temprana y de los efectos clínicos del tiempo de consumo. Objetivo Se analizó el rendimiento clínico y cognitivo de usuarios de inhalables y los efectos clínicos del tiempo de consumo. Método Estudio transversal en el que se incluyeron 28 adultos usuarios de inhalables, divididos en dos grupos dependiendo del tiempo de consumo, menor o mayor a siete años. Todos fueron evaluados en términos de valores clínicos y neuropsicológicos. Resultados Los consumidores de inhalables mostraron presencia de craving (M = 479.14, SD = 213.51), comportamiento frontal alterado antes (M = 119.18, SD = 29.53) y actualmente (M = 130, SD = 33.03), problemas para dormir (M = 8.93, SD = 3.4) y dificultades cognitivas (control inhibitorio, planificación, toma de decisiones, memoria de trabajo, fluidez verbal y flexibilidad cognitiva); todas estas tareas fueron estadísticamente significativas (p = < .05). Discusión y conclusión El funcionamiento ejecutivo se ve afectado en el trastorno por uso de inhalables. Estas alteraciones aumentan en la abstinencia y en la apetencia, y los cambios se mantienen independientes del tiempo de uso.

Clinical and behavioral profile of young inhalant users.

INTRODUCTION: Currently, misuse inhalants is increasing: addictive potential has been demonstrated in several studies. Until now there was no quantifiable clinical evidence of behavioral characteristics inhalant users. Main objective was to evaluate craving, impulsivity, frontalized behaviors and recognition of emotions in young inhalant users. METHOD: Eleven male, aged 15-22 years (17.73±2.14), schooling 3-12 years (8.18±2.56) were evaluated. RESULTS: Evaluation showed that inhalant users exhibit signs of craving, high ranges of impulsivity, frontal behavioral deficits and difficulties detection of emotional expressions. CONCLUSIONS: In inhalants addiction, symptoms of craving and behavioral alterations are exhibited, time use increases frontal behaviors.

Perfil clínico y conductual de jóvenes usuarios de inhalables / Clinical and behavioral profile of young inhalant users

Introducción. En la actualidad el uso indebido de inhalables está aumentando: el potencial adictivo se ha demostrado en diversos estudios. Hasta ahora no había evidencia clínica cuantificable de las características conductuales de los usuarios de inhalables. El objetivo principal fue evaluar el craving, la impulsividad, los comportamientos frontalizados y el reconocimiento de emociones en jóvenes usuarios de inhalables. Método. Fueron evaluados once varones, edades entre 15-22 años (17,3 ± 2,14), escolaridad entre 3-12 años (8,18 ± 2,56). Resultados. La evaluación evidenció que los usuarios de inhalables exhiben indicios de craving, rangos elevados de impulsividad, déficits comportamentales del sistema frontal y dificultades para la detección de expresiones emocionales. Conclusión. En la adicción a inhalables se exhiben síntomas de craving y alteraciones comportamentales, el tiempo de uso incrementa los comportamientos frontales

Introduction. Currently, misuse inhalants is increasing: addictive potential has been demonstrated in several studies. Until now there was no quantifiable clinical evidence of behavioral characteristics inhalant users. Main objective was to evaluate craving, impulsivity, frontalized behaviors and recognition of emotions in young inhalant users. Method. Eleven male, aged 15-22 years (17.73±2.14), schooling 3-12 years (8.18 ± 2.56) were evaluated. Results. Evaluation showed that inhalant users exhibit signs of craving, high ranges of impulsivity, frontal behavioral deficits and difficulties detection of emotional expressions. Conclusions. In inhalants addiction, symptoms of craving and behavioral alterations are exhibited, time use increases frontal behaviors

Identifying cognitive deficits in cocaine dependence using standard tests and machine learning.

There is a growing need to address the variability in detecting cognitive deficits with standard tests in cocaine dependence (CD). The aim of the current study was to identify cognitive deficits by means of Machine Learning (ML) algorithms: Generalized Linear Model (Glm), Random forest (Rf) and Elastic Net (GlmNet), to allow more effective categorization of CD and Non-dependent controls (NDC and to address common methodological problems. For our validation, we used two independent datasets, the first consisted of 87 participants (53 CD and 34 NDC) and the second of 40 participants (20 CD and 20 NDC). All participants were evaluated with neuropsychological tests that included 40 variables assessing cognitive domains. Using results from the cognitive evaluation, the three ML algorithms were trained in the first dataset and tested on the second to classify participants into CD and NDC. While the three algorithms had a receiver operating curve (ROC) performance over 50%, the GlmNet was superior in both the training (ROC = 0.71) and testing datasets (ROC = 0.85) compared to Rf and Glm. Furthermore, GlmNet was capable of identifying the eight main predictors of group assignment (CD or NCD) from all the cognitive domains assessed. Specific variables from each cognitive test resulted in robust predictors for accurate classification of new cases, such as those from cognitive flexibility and inhibition domains. These findings provide evidence of the effectiveness of ML as an approach to highlight relevant sections of standard cognitive tests in CD, and for the identification of generalizable cognitive markers.

Effects of Childhood Maltreatment on Social Cognition and Brain Functional Connectivity in Borderline Personality Disorder Patients.

Borderline personality disorder (BPD) is a chronic condition characterized by high levels of impulsivity, affective instability, and difficulty to establish and manage interpersonal relationships. However, little is known about its etiology and neurobiological substrates. In our study, we wanted to investigate the influence of child abuse in the psychopathology of BPD by means of social cognitive paradigms [the Movie for the Assessment of Social Cognition (MASC) and the reading the mind in the eyes test (RMET)], and resting state functional magnetic resonance imaging (rs-fMRI). For this, we recruited 33 participants, 18 BPD patients, and 15 controls. High levels of self-reported childhood maltreatment were reported by BPD patients. For the sexual abuse subdimension, there were no differences between the BPD and the control groups, but there was a negative correlation between MASC scores and total childhood maltreatment levels, as well as between physical abuse, physical negligence, and MASC. Both groups showed that the higher the level of childhood maltreatment, the lower the performance on the MASC social cognitive test. Further, in the BPD group, there was hypoconnectivity between the structures responsible for emotion regulation and social cognitive responses that have been described as part of the frontolimbic circuitry (i.e., amygdala). Differential levels of connectivity, associated with different types and levels of abuse were also observed.

Funcionamiento cognitivo en sujetos con trastorno de dependencia a cocaína y crack durante la abstinencia temprana / Cognitive functions of subjects with cocaine and crack dependency disorder during early abstinence

Introducción. Los efectos cognitivos causados por el consumo de cocaína y crack, especialmente los déficits de las funciones ejecutivas, aumentan la probabilidad de un comportamiento de búsqueda de drogas e interfieren en la capacidad de los usuarios de asimilar y participar en los programas de rehabilitación. Objetivo. Determinar en la abstinencia temprana el estado de las funciones ejecutivas, la impulsividad y la ansiedad (craving) en consumidores de cocaína y crack. Sujetos y métodos. Este estudio transversal tuvo una muestra de 60 hombres, con una edad media de 31,38 ± 7,26 años, distribuidos en tres grupos: usuarios que inhalan cocaína (CDP-I; n = 15), con una edad de inicio de consumo de 23,13 ± 7,2 años; consumidores de cocaína en crack (CDP-C; n = 26), con una edad de inicio de consumo de 20,81 ± 4,21 años, y un grupo control de sujetos sin adicción (n = 19). Se aplicaron evaluaciones sociodemográficas, clínicas y cognitivas. Resultados. Los datos mostraron diferencias significativas en las puntuaciones del nivel socioeconómico e impulsividad. Los grupos de consumidores tienen puntuaciones más bajas con respecto al grupo control. El grupo CDP-C mostró rendimientos pobres en comparación con el grupo CDP-I y el grupo control en las pruebas de Berg, torre de Londres, números en orden y sustracción directos. El grupo CDP-I mostró una menor puntuación en la planificación comparada con los otros dos grupos. Conclusiones. En la abstinencia temprana, los consumidores de crack manifiestan mayor número de déficits, principalmente en la memoria de trabajo, la planificación y la flexibilidad cognitiva

Introduction. Cognitive effects caused by cocaine and crack consumption, especially deficits in executive functions may increase the likelihood of drug-seeking behaviour and interfere with the ability of users to assimilate and participate in rehabilitation programs. Aim. To determine in early abstinence the state of executive functions, the impulsiveness and craving in cocaine and crack consumers. Subjects and methods. This cross-sectional study functions, with a sample of 60 male aged between 31.38 ± 7.26 years old, distributed in three groups: inhaled cocaine users (CDP-I; n = 15), with 23.13 ± 7.2 age of onset of consumption; crack cocaine users (CDP-C; n = 26), with 20.81 ± 4.21 age of onset of consumption, and a control groups of no-addiction individuals (n = 19). Sociodemographic, clinical and cognitive assessments were applied. Results. The data showed that significant differences in socioeconomic level score and impulsiveness. Consumer groups have with lower scores with respect the control group. CDP-C group showed poor performances compared to the CDP-I and control groups, in the Berg Test, Tower of London, numbers in the direct order and subtraction. CDP-I group showed less score in planning compare with the other two groups. Conclusions. In early abstinence crack users manifest a greater number of deficits, mainly in working memory, planning and cognitive flexibility

Emotional facial expressions during REM sleep dreams.

Although motor activity is actively inhibited during rapid eye movement (REM) sleep, specific activations of the facial mimetic musculature have been observed during this stage, which may be associated with greater emotional dream mentation. Nevertheless, no specific biomarker of emotional valence or arousal related to dream content has been identified to date. In order to explore the electromyographic (EMG) activity (voltage, number, density and duration) of the corrugator and zygomaticus major muscles during REM sleep and its association with emotional dream mentation, this study performed a series of experimental awakenings after observing EMG facial activations during REM sleep. The study was performed with 12 healthy female participants using an 8-hr nighttime sleep recording. Emotional tone was evaluated by five blinded judges and final valence and intensity scores were obtained. Emotions were mentioned in 80.4% of dream reports. The voltage, number, density and duration of facial muscle contractions were greater for the corrugator muscle than for the zygomaticus muscle, whereas high positive emotions predicted the number (R2 0.601, p = 0.0001) and voltage (R2 0.332, p = 0.005) of the zygomaticus. Our findings suggest that zygomaticus events were predictive of the experience of positive affect during REM sleep in healthy women.

Borderline Personality Disorder With Cocaine Dependence: Impulsivity, Emotional Dysregulation and Amygdala Functional Connectivity.

Background: Borderline personality disorder is present in 19% of cocaine dependence cases; however, this dual pathology is poorly understood. We wished to characterize the dual pathology and find its functional connectivity correlates to better understand it. Methods: We recruited 69 participants divided into 4 groups: dual pathology (n = 20), cocaine dependence without borderline personality disorder (n = 19), borderline personality without cocaine dependence (n = 10) and healthy controls (n = 20). We used self-reported instruments to measure impulsivity and emotional dysregulation. We acquired resting state fMRI and performed seed-based analyses of the functional connectivity of bilateral amygdala. Results: Borderline personality disorder and cocaine dependence as factors had opposing effects in impulsivity and emotional dysregulation, as well as on functional connectivity between left amygdala and medial prefrontal cortex. On the other hand, in the functional connectivity between right amygdala and left insula, the effect of having both disorders was instead additive, reducing functional connectivity strength. The significant functional connectivity clusters were correlated with impulsivity and emotional dysregulation. Conclusions: In this study, we found that clinical scores of dual pathology patients were closer to those of borderline personality disorder without cocaine dependence than to those of cocaine dependence without borderline personality disorder, while amygdala-medial prefrontal cortex functional connectivity patterns in dual pathology patients were closer to healthy controls than expected.

Clinical improvement in patients with borderline personality disorder after treatment with repetitive transcranial magnetic stimulation: preliminary results

Objective: Current treatment of borderline personality disorder (BPD) consists of psychotherapy and pharmacological interventions. However, the use of repetitive transcranial magnetic stimulation (rTMS) could be beneficial to improve some BPD symptoms. The objective of this study was to evaluate clinical improvement in patients with BPD after application of rTMS over the right or left dorsolateral prefrontal cortex (DLPFC). Method: Twenty-nine patients with BPD from the National Institute of Psychiatry, Mexico, were randomized in two groups to receive 15 sessions of rTMS applied over the right (1 Hz, n=15) or left (5 Hz, n=14) DLPFC. Improvement was measured by the Clinical Global Impression Scale for BPD (CGI-BPD), Borderline Evaluation of Severity Over Time (BEST), Beck Depression Inventory (BDI), Hamilton Anxiety Rating Scale (HAM-A), and Barratt Impulsiveness Scale (BIS). Results: Intragroup comparison showed significant (p < 0.05) reductions in every psychopathologic domain of the CGI-BPD and in the total scores of all scales in both groups. Conclusions: Both protocols produced global improvement in severity and symptoms of BPD, particularly in impulsiveness, affective instability, and anger. Further studies are warranted to explore the therapeutic effect of rTMS in BPD. Clinical trial registration: NCT02273674.

Clinical improvement in patients with borderline personality disorder after treatment with repetitive transcranial magnetic stimulation: preliminary results.

OBJECTIVE: Current treatment of borderline personality disorder (BPD) consists of psychotherapy and pharmacological interventions. However, the use of repetitive transcranial magnetic stimulation (rTMS) could be beneficial to improve some BPD symptoms. The objective of this study was to evaluate clinical improvement in patients with BPD after application of rTMS over the right or left dorsolateral prefrontal cortex (DLPFC). METHOD: Twenty-nine patients with BPD from the National Institute of Psychiatry, Mexico, were randomized in two groups to receive 15 sessions of rTMS applied over the right (1 Hz, n=15) or left (5 Hz, n=14) DLPFC. Improvement was measured by the Clinical Global Impression Scale for BPD (CGI-BPD), Borderline Evaluation of Severity Over Time (BEST), Beck Depression Inventory (BDI), Hamilton Anxiety Rating Scale (HAM-A), and Barratt Impulsiveness Scale (BIS). RESULTS: Intragroup comparison showed significant (p < 0.05) reductions in every psychopathologic domain of the CGI-BPD and in the total scores of all scales in both groups. CONCLUSIONS: Both protocols produced global improvement in severity and symptoms of BPD, particularly in impulsiveness, affective instability, and anger. Further studies are warranted to explore the therapeutic effect of rTMS in BPD. CLINICAL TRIAL REGISTRATION: NCT02273674

Evidence of validity of an inhalant-craving questionnaire.

Inhalants are substances widely used as recreational drugs: their addictive potential has been demonstrated by many studies. There is no reported measurable evidence of craving in inhalant users. The main goal of this study was to design and obtain evidence of validity of the score of a questionnaire for the evaluation of inhalant craving (ICQ) in a Mexican population sample. The ICQ is a type of visual analog scale with ten items. Face validity was evaluated by a group of experts in the addiction field. Reviewers considered the completeness, semantics, and sentence structure to guarantee a conceptual representation of the items. The final ICQ was applied to a sample of 520 Mexican high school students, 46% women and 54% men, between 12-19 years of age (M=15.18; SD=1.48), from 7th to 12th grades. The internal consistency of the ICQ showed a Cronbach's Alpha of 0.947. The 10 items were grouped into one single factor, with a factor loading above 0.74 for each of them. ROC analysis breakpoint was located at 18.5 mm with a sensitivity of 0.855 and specificity of 0.753. Thirty-three per cent (n= 172) of the student population evaluated reported the use of inhalants at some point in their lifetimes, with an average of misuse beginning at 13.6 years of age. The ICQ showed adequate psychometric properties, suggesting that the instrument may be considered a useful tool for screening for craving in young inhalant users.

Los inhalables son sustancias ampliamente utilizadas como drogas recreativas: su potencial adictivo ha sido demostrado por numerosos estudios. No hay reportada evidencia medible del craving en usuarios de inhalables. El objetivo principal de este trabajo fue diseñar y obtener las evidencias de validez de las puntuaciones en un cuestionario para la evaluación del craving a sustancias inhalables (ICQ) en una muestra de población mexicana. El ICQ es un tipo de escala análoga visual de diez ítems. La validación de apariencia fue evaluada por un grupo de expertos en el campo de las adicciones. Los revisores consideraron la integridad, la semántica y la estructura de los enunciados, para garantizar una representación conceptual de los ítems. La versión final del ICQ fue aplicada a una muestra de 520 estudiantes mexicanos, 46% mujeres y 54% hombres, con edad comprendidas entre 12-19 años (M=15.18; SD=1.48), con años de escolaridad entre 7-12 años. La consistencia interna del ICQ mostró un Alfa de Cronbach de 0.947. Los 10 ítems se agruparon en un solo factor, con una carga factorial por encima de 0.74 para cada uno de ellos. El análisis ROC mostró que el punto de corte se localizó a 18.5 mm con una sensibilidad de 0.855 y especificidad de 0.753. El 33% (n=172) de la población de estudiantes evaluados reportó el uso de inhalables en algún momento de su vida, con un promedio de edad de inicio de 13.6 años. El ICQ mostró propiedades psicométricas adecuadas, lo que sugiere que el instrumento puede ser una herramienta útil para el tamizaje de craving en jóvenes usuarios de inhalables.

Evidencias de validez de un cuestionario de craving a inhalables / Evidence of validity of an inhalant-craving questionnaire

Los inhalables son sustancias ampliamente utilizadas como drogas recreativas: su potencial adictivo ha sido demostrado por numerosos estudios. No hay reportada evidencia medible del craving en usuarios de inhalables. El objetivo principal de este trabajo fue diseñar y obtener las evidencias de validez de las puntuaciones en un cuestionario para la evaluación del craving a sustancias inhalables (ICQ) en una muestra de población mexicana. El ICQ es un tipo de escala análoga visual de diez ítems. La validación de apariencia fue evaluada por un grupo de expertos en el campo de las adicciones. Los revisores consideraron la integridad, la semántica y la estructura de los enunciados, para garantizar una representación conceptual de los ítems. La versión final del ICQ fue aplicada a una muestra de 520 estudiantes mexicanos, 46% mujeres y 54% hombres, con edad comprendidas entre 12-19 años (M=15.18; SD=1.48), con años de escolaridad entre 7-12 años. La consistencia interna del ICQ mostró un Alfa de Cronbach de 0.947. Los 10 ítems se agruparon en un solo factor, con una carga factorial por encima de 0.74 para cada uno de ellos. El análisis ROC mostró que el punto de corte se localizó a 18.5 mm con una sensibilidad de 0.855 y especificidad de 0.753. El 33% (n=172) de la población de estudiantes evaluados reportó el uso de inhalables en algún momento de su vida, con un promedio de edad de inicio de 13.6 años. El ICQ mostró propiedades psicométricas adecuadas, lo que sugiere que el instrumento puede ser una herramienta útil para el tamizaje de craving en jóvenes usuarios de inhalables

Inhalants are substances widely used as recreational drugs: their addictive potential has been demonstrated by many studies. There is no reported measurable evidence of craving in inhalant users. The main goal of this study was to design and obtain evidence of validity of the score of a questionnaire for the evaluation of inhalant craving (ICQ) in a Mexican population sample. The ICQ is a type of visual analog scale with ten items. Face validity was evaluated by a group of experts in the addiction field. Reviewers considered the completeness, semantics, and sentence structure to guarantee a conceptual representation of the items. The final ICQ was applied to a sample of 520 Mexican high school students, 46% women and 54% men, between 12-19 years of age (M=15.18; SD=1.48), from 7th to 12th grades. The internal consistency of the ICQ showed a Cronbach’s Alpha of 0.947. The 10 items were grouped into one single factor, with a factor loading above 0.74 for each of them. ROC analysis breakpoint was located at 18.5 mm with a sensitivity of 0.855 and specificity of 0.753. Thirty-three per cent (n= 172) of the student population evaluated reported the use of inhalants at some point in their lifetimes, with an average of misuse beginning at 13.6 years of age. The ICQ showed adequate psychometric properties, suggesting that the instrument may be considered a useful tool for screening for craving in young inhalant users

Análisis de fuentes del EEG en pacientes tratados con estimulación magnética transcraneal a 5 Hz como tratamiento antidepresivo / Electroencephalographic source analysis in patients receiving 5-Hz transcranial magnetic stimulation as antidepressant treatment

Transcranial Magnetic Stimulation (rTMS) is a technique that allows noninvasive electrical stimulation of the cortex with few side effects. An antidepressant effect has been proposed when rTMS is delivered over prefrontal dorsolateral cortex (DLPFC) ≥5Hz. Quantitative EEG studies have shown increases in alpha and theta power bands as well as frontal interhemispheric asymmetries in most recordings from depressed patients. rTMS over left DLPFC at 5Hz involve a safer and more tolerable procedure, and its neurophysiological correlates has not been explored using EEG source analysis. The aim of this research was to study changes in EEG sources using VARTERA method in a group of patients with major depressive disorder (MDD) treated with 5Hz rTMS over left DLPFC as single or combined treatment with escitalopram. Methods 18 patients with DSM-IV MDD diagnosis without treatment for the current episode were included. Subjects were randomly assigned to one of two groups: A) rTMS+escitalopram 10mg, n=9; B) rTMS+placebo, n=9. Subjects received 15 sessions of rTMS on a daily basis. In order to compare changes in EEG sources two recordings were obtained, prior and after treatment. HDRS, BDI and HARD were used for clinical assessments. Results All patients of group A and eight patients of group B showed response to treatment (considered as a reduction of 50% in HDRS score). An increase in absolute power at 9.37Hz and 10.17Hz in temporal and postcentral gyrus on the left hemisphere was found in group B. Absolute power in those frequencies was decreased in the same regions for group A. In addition, an increased power in beta band frequencies was observed in both hemispheres for group A. Conclusion Increases in alpha band could be the hallmark of the 5Hz rTMS, but it could be reduced by escitalopram. Besides, increases observed in beta band for group A could be related to escitalopram effect.

La estimulación magnética transcraneal repetitiva (EMTr) es una técnica que permite estimular eléctricamente la corteza cerebral de manera no invasiva y con pocos efectos secundarios. Se ha propuesto que la EMTr aplicada sobre la corteza prefrontal dorsolateral (CPFDL) izquierda con frecuencias ≥5Hz tiene efectos antidepresivos. Se ha encontrado que en el electroencefalograma cuantitativo (QEEG por sus siglas en inglés) la mayoría de pacientes deprimidos presentan incrementos en las bandas theta y alfa, así como asimetrías interhemisféricas en la actividad alfa en regiones anteriores. La EMTr sobre la CPFDL izquierda a 5Hz ofrece ventajas considerables en seguridad y tolerabilidad; sin embargo, sus correlatos neurofisiológicos no han sido explorados por el análisis de fuentes del EEG. Objetivo Estudiar los cambios en las fuentes del EEG según el método VARETA en un grupo de pacientes con trastorno depresivo mayor que recibieron EMTr a 5Hz sobre la corteza prefrontal dorsolateral izquierda como tratamiento único o en combinación con escitalopram. Material y métodos Se estudiaron 18 pacientes con diagnóstico de trastorno depresivo mayor de acuerdo con los criterios del DSM-IV sin tratamiento para el episodio en curso. Los sujetos habían sido aleatoriamente asignados a uno de los siguientes grupos de tratamiento: A) EMTr+escitalopram 10mg, n=9; B) EMTr+placebo, n=9. Se aplicó EMTr, a 5Hz en una sesión diaria durante 15 días. Se obtuvieron dos registros electroencefalográficos, uno basal y otro final, con el fin de comparar los cambios en las fuentes de actividad eléctrica cerebral, pretratamiento y post-tratamiento. Se realizaron evaluaciones clinimétricas con las escalas de Hamilton para Depresión y Ansiedad y el Inventario de Depresión de Beck. Resultados Todos los pacientes en el grupo A y ocho pacientes en el grupo B respondieron al tratamiento, con una reducción de 50% o más en la escala HDRS. En el análisis de fuentes se encontró un efecto en el grupo B caracterizado por incremento en la PA de 9.37 a 10.17Hz, en regiones temporales y giro poscentral izquierdos, mismo que se encontró disminuido en el grupo A, Además se encontró un incremento en fracuencias correspondientes a la banda beta en regiones frontales de ambos hemisferios en el grupo A. Conclusiones Podría considerarse que el incremento en la banda alfa es característico de la EMTr a 5Hz, mismo que se ve reducido por efecto del escitalopram. Por otro lado, se observó que el grupo A mostró incrementos en fuentes correspondientes a la banda beta como posible efecto relacionado del fármaco antidepresivo.

EEG sources in a group of patients with major depressive disorders.

EEG sources were assessed in a group of patients with major moderate-severe depressive disorder (MDD) as classified by trained clinicians according to DSM-IV criteria. Frequency Domain Variable Resolution Electromagnetic Tomography (FD-VARETA) was used to calculate EEG sources. The Z-values indicated that EEG sources were abnormal (increase in current density) in all patients, with most demonstrating abnormal EEG sources in both hemispheres but with maximal inverse solution located primarily in the right. Twenty-nine patients had a predominant topography of the abnormal EEG maximal inverse solution in the frontal lobes. The remaining seven patients had a bilateral abnormal increase in current density in the superior parietal lobe. The EEG maximal abnormal inverse solution frequency was observed in both hemispheres such that the increases in current density were prevalent in alpha and theta bands. The results suggest that any of the two hemispheres could be affected by MDD, but abnormal EEG sources can be found more frequently in the right one, with the maximal abnormal inverse solution at the alpha and theta bands in frontal and parietal cortices.