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1.
Neuroimage ; 57(4): 1524-33, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21679770

RESUMEN

There is mounting evidence that mindfulness meditation is beneficial for the treatment of mood and anxiety disorders, yet little is known regarding the neural mechanisms through which mindfulness modulates emotional responses. Thus, a central objective of this functional magnetic resonance imaging study was to investigate the effects of mindfulness on the neural responses to emotionally laden stimuli. Another major goal of this study was to examine the impact of the extent of mindfulness training on the brain mechanisms supporting the processing of emotional stimuli. Twelve experienced (with over 1000 h of practice) and 10 beginner meditators were scanned as they viewed negative, positive, and neutral pictures in a mindful state and a non-mindful state of awareness. Results indicated that the Mindful condition attenuated emotional intensity perceived from pictures, while brain imaging data suggested that this effect was achieved through distinct neural mechanisms for each group of participants. For experienced meditators compared with beginners, mindfulness induced a deactivation of default mode network areas (medial prefrontal and posterior cingulate cortices) across all valence categories and did not influence responses in brain regions involved in emotional reactivity during emotional processing. On the other hand, for beginners relative to experienced meditators, mindfulness induced a down-regulation of the left amygdala during emotional processing. These findings suggest that the long-term practice of mindfulness leads to emotional stability by promoting acceptance of emotional states and enhanced present-moment awareness, rather than by eliciting control over low-level affective cerebral systems from higher-order cortical brain regions. These results have implications for affect-related psychological disorders.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiología , Emociones/fisiología , Meditación/psicología , Adulto , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
2.
Psychiatry Res ; 174(3): 231-9, 2009 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-19914046

RESUMEN

Recent advances in power spectral analysis of electroencephalography (EEG) signals and brain-computer interface (BCI) technology may significantly contribute to the development of psychoneurotherapies. The goal of this study was to measure the effect of a psychoneurotherapy on brain source generators of abnormal EEG activity in individuals with major depressive disorder (MDD). Thirty participants with unipolar MDD were recruited in the community. The proposed psychoneurotherapy was developed based on the relationship between the localization of abnormal EEG activity and depressive symptomatology. Brain electromagnetic abnormalities in MDD were identified with low resolution brain electromagnetic tomography (LORETA) and a normative EEG database. Localization of brain changes after treatment was assessed through the standardized version of LORETA (sLORETA). Before treatment, excessive high-beta (18-30 Hz) activity was noted in several brain regions located in the fronto-temporal regions. After treatment, only participants who successfully normalized EEG activity in cortico-limbic/paralimbic regions could be considered in clinical remission. In these regions, significant correlations were found between the percentage of change of depressive symptoms and the percentage of reduction in high-beta activity. These results suggest that the normalization of high-beta activity in cortico-limbic/paralimbic regions can be associated with a significant reduction of depressive symptoms.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiopatología , Terapia Cognitivo-Conductual/métodos , Trastorno Depresivo Mayor/patología , Trastorno Depresivo Mayor/fisiopatología , Magnetoencefalografía/métodos , Adulto , Encéfalo/patología , Trastorno Depresivo Mayor/terapia , Electroencefalografía , Femenino , Lateralidad Funcional , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pruebas Neuropsicológicas , Autoimagen , Análisis Espectral , Encuestas y Cuestionarios
3.
Psychiatry Res ; 172(2): 93-8, 2009 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-19321316

RESUMEN

Functional neuroimaging studies have shown that romantic love and maternal love are mediated by regions specific to each, as well as overlapping regions in the brain's reward system. Nothing is known yet regarding the neural underpinnings of unconditional love. The main goal of this functional magnetic resonance imaging study was to identify the brain regions supporting this form of love. Participants were scanned during a control condition and an experimental condition. In the control condition, participants were instructed to simply look at a series of pictures depicting individuals with intellectual disabilities. In the experimental condition, participants were instructed to feel unconditional love towards the individuals depicted in a series of similar pictures. Significant loci of activation were found, in the experimental condition compared with the control condition, in the middle insula, superior parietal lobule, right periaqueductal gray, right globus pallidus (medial), right caudate nucleus (dorsal head), left ventral tegmental area and left rostro-dorsal anterior cingulate cortex. These results suggest that unconditional love is mediated by a distinct neural network relative to that mediating other emotions. This network contains cerebral structures known to be involved in romantic love or maternal love. Some of these structures represent key components of the brain's reward system.


Asunto(s)
Encéfalo/fisiología , Emociones/fisiología , Amor , Adulto , Mapeo Encefálico , Femenino , Lateralidad Funcional/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Motivación , Vías Nerviosas/fisiología , Oxígeno/sangre , Recompensa
4.
Prog Neurobiol ; 81(4): 218-36, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17349730

RESUMEN

This article reviews neuroimaging studies of conscious and voluntary regulation of various emotional states (sexual arousal, sadness, negative emotion). The results of these studies show that metacognition and cognitive recontextualization selectively alters the way the brain processes and reacts to emotional stimuli. Neuroimaging studies of the effect of psychotherapy in patients suffering from diverse forms of psychopathology (obsessive-compulsive disorder, panic disorder, unipolar major depressive disorder, social phobia, spider phobia, borderline personality) are also examined. The results of these studies indicate that the mental functions and processes involved in diverse forms of psychotherapy exert a significant influence on brain activity. Neuroimaging investigations of the placebo effect in healthy individuals (placebo analgesia, psychostimulant expectation) and patients with Parkinson's disease or unipolar major depressive disorder are also reviewed. The results of these investigations demonstrate that beliefs and expectations can markedly modulate neurophysiological and neurochemical activity in brain regions involved in perception, movement, pain, and various aspects of emotion processing. Collectively, the findings of the neuroimaging studies reviewed here strongly support the view that the subjective nature and the intentional content (what they are "about" from a first-person perspective) of mental processes (e.g., thoughts, feelings, beliefs, volition) significantly influence the various levels of brain functioning (e.g., molecular, cellular, neural circuit) and brain plasticity. Furthermore, these findings indicate that mentalistic variables have to be seriously taken into account to reach a correct understanding of the neural bases of behavior in humans. An attempt is made to interpret the results of these neuroimaging studies with a new theoretical framework called the Psychoneural Translation Hypothesis.


Asunto(s)
Emociones , Trastornos del Humor/psicología , Trastornos del Humor/terapia , Efecto Placebo , Psicoterapia/métodos , Controles Informales de la Sociedad/métodos , Animales , Humanos
5.
Nord J Psychiatry ; 63(1): 5-16, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19023697

RESUMEN

Mentalistic variables must be considered to reach a correct understanding of the neurophysiological basis of behavior in humans. Confusion regarding the relative importance of neurophysiological and mentalistic variables can lead to important misconceptions about causes and effects in the study of human behavior. In this article, we review neuroimaging studies of the effect of psychotherapy in patients suffering from diverse forms of psychopathology (obsessive-compulsive disorder, panic disorder, unipolar major depressive disorder, spider phobia). We also review neuroimaging studies of the placebo effect in healthy individuals (placebo analgesia, psychostimulant expectation) and patients with Parkinson's disease or unipolar major depressive disorder. Mental functions and processes involved in diverse forms of psychotherapy exert a significant influence on brain activity. With regard to the placebo effect, beliefs and expectations can markedly modulate neurophysiological and neurochemical activity in brain regions involved in perception, movement, pain and various aspects of emotion processing. The findings of the neuroimaging studies reviewed here strongly support the view that the subjective nature and the intentional content of mental processes significantly influence the various levels of brain functioning (e.g. molecular, cellular, neural circuit) and brain plasticity.


Asunto(s)
Encéfalo/fisiopatología , Imagen por Resonancia Magnética , Trastornos Mentales/fisiopatología , Procesos Mentales/fisiología , Tomografía de Emisión de Positrones , Tomografía Computarizada de Emisión de Fotón Único , Mapeo Encefálico , Terapia Cognitivo-Conductual , Trastorno Depresivo Mayor/fisiopatología , Humanos , Enfermedad de Parkinson/fisiopatología , Trastornos Fóbicos/fisiopatología , Efecto Placebo , Psicofisiología , Psicoterapia
6.
Neurosci Lett ; 444(1): 1-4, 2008 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-18721862

RESUMEN

Mystical experiences relate to a fundamental dimension of human existence. These experiences, which are characterized by a sense of union with God, are commonly reported across all cultures. To date, no electroencephalography (EEG) study has been conducted to identify the neuroelectrical correlates of such experiences. The main objective of this study was to measure EEG spectral power and coherence in 14 Carmelite nuns during a mystical experience. EEG activity was recorded from 19 scalp locations during a resting state, a control condition and a mystical condition. In the mystical condition compared to control condition, electrode sites showed greater theta power at F3, C3, P3, Fz, Cz and Pz, and greater gamma1 power was detected at T4 and P4. Higher delta/beta ratio, theta/alpha ratio and theta/beta ratio were found for several electrode sites. In addition, FP1-C3 pair of electrodes displayed greater coherence for theta band while F4-P4, F4-T6, F8-T6 and C4-P4 pairs of electrodes showed greater coherence for alpha band. These results indicate that mystical experiences are mediated by marked changes in EEG power and coherence. These changes implicate several cortical areas of the brain in both hemispheres.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiología , Electroencefalografía , Misticismo , Adulto , Electroencefalografía/clasificación , Femenino , Humanos , Persona de Mediana Edad
8.
J Clin Psychiatry ; 67(3): 342-50, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16649818

RESUMEN

BACKGROUND: The lifetime prevalence of substance use disorders among schizophrenia patients is close to 50%. The negative consequences of substance abuse in schizophrenia are well documented, but the etiology of this comorbid condition remains unknown. According to the affect regulation model, schizophrenia patients abuse drugs in order to cope with their negative affects. Supporting the model, clinical studies have shown that dual-diagnosis patients have less blunting of affect and that they experience more negative affect. We hypothesized that patients with a history of substance use would have increased cerebral activations in response to aversive stimuli when compared to abstinent patients. METHOD: Schizophrenia patients were divided into 2 groups: patients with (SCZ-SU group; N = 12) and without (SCZ group; N = 11) a current or past substance use disorder (alcohol, cannabis, and/or LSD). Diagnoses were made according to DSM-IV criteria. Using functional magnetic resonance imaging (fMRI), patients were scanned during passive viewing of emotionally negative pictures (International Affective Picture System). Data were gathered from September 2001 to December 2003. RESULTS: Subjectively, the emotional experience induced by viewing the negative pictures was rated significantly higher in the SCZ-SU group than in the SCZ group (p = .008). Neurally, in the SCZ-SU group, significant loci of activation were identified in the right medial prefrontal cortex (Brodmann's area [BA] 10), left medial prefrontal cortex (BA 10), right orbitofrontal cortex (BA 47), and left amygdala. No significant loci of activation were observed in the SCZ group. CONCLUSIONS: These results suggest that the functioning of the medial prefrontal cortex, thought to be impaired in patients with prominent negative symptoms, is more preserved in dual-diagnosis schizophrenia. This relative preservation could be primary or secondary to substance use.


Asunto(s)
Afecto/fisiología , Imagen por Resonancia Magnética/estadística & datos numéricos , Modelos Neurológicos , Corteza Prefrontal/fisiología , Esquizofrenia/diagnóstico , Trastornos Relacionados con Sustancias/diagnóstico , Adaptación Psicológica/fisiología , Adulto , Mapeo Encefálico , Corteza Cerebral/fisiología , Comorbilidad , Diagnóstico Dual (Psiquiatría) , Femenino , Lateralidad Funcional/fisiología , Humanos , Sistema Límbico/fisiología , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Escalas de Valoración Psiquiátrica , Esquizofrenia/epidemiología , Psicología del Esquizofrénico , Automedicación/psicología , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/psicología
9.
Neuroreport ; 17(8): 843-6, 2006 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-16708026

RESUMEN

An inability to self-regulate negative emotions appears to play a pivotal role in the genesis of major depressive disorder. This inability may be related to a dysfunction of the neural circuitry underlying emotional self-regulation. This functional magnetic resonance imaging study was conducted to test this hypothesis. Depressed individuals and controls were scanned while they attempted to voluntarily down-regulate sad feelings. The degree of difficulty experienced during down-regulation of sadness was higher in depressed individuals. Furthermore, there was greater activation in the right dorsal anterior cingulate cortex, right anterior temporal pole, right amygdala, and right insula in depressed individuals. These results suggest that emotional dysregulation in major depressive disorder is related to a disturbance in the neural circuitry of emotional self-regulation.


Asunto(s)
Encéfalo/fisiopatología , Trastorno Depresivo Mayor/fisiopatología , Emociones/fisiología , Sistema Límbico/fisiopatología , Vías Nerviosas/fisiopatología , Adulto , Amígdala del Cerebelo/anatomía & histología , Amígdala del Cerebelo/fisiopatología , Encéfalo/anatomía & histología , Mapeo Encefálico , Corteza Cerebral/anatomía & histología , Corteza Cerebral/fisiopatología , Trastorno Depresivo Mayor/diagnóstico , Regulación hacia Abajo/fisiología , Femenino , Lóbulo Frontal/anatomía & histología , Lóbulo Frontal/fisiopatología , Lateralidad Funcional/fisiología , Giro del Cíngulo/anatomía & histología , Giro del Cíngulo/fisiopatología , Humanos , Sistema Límbico/anatomía & histología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/anatomía & histología , Valor Predictivo de las Pruebas
10.
Neurosci Lett ; 405(3): 186-90, 2006 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-16872743

RESUMEN

The main goal of this functional magnetic resonance imaging (fMRI) study was to identify the neural correlates of a mystical experience. The brain activity of Carmelite nuns was measured while they were subjectively in a state of union with God. This state was associated with significant loci of activation in the right medial orbitofrontal cortex, right middle temporal cortex, right inferior and superior parietal lobules, right caudate, left medial prefrontal cortex, left anterior cingulate cortex, left inferior parietal lobule, left insula, left caudate, and left brainstem. Other loci of activation were seen in the extra-striate visual cortex. These results suggest that mystical experiences are mediated by several brain regions and systems.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiología , Procesos Mentales/fisiología , Misticismo , Adulto , Encéfalo/irrigación sanguínea , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Oxígeno/sangre
11.
Neurosci Lett ; 394(3): 216-21, 2006 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-16343769

RESUMEN

Attention Deficit Hyperactivity Disorder (AD/HD) is a neurodevelopmental disorder mainly characterized by impairments in cognitive functions. Functional neuroimaging studies carried out in individuals with AD/HD have shown abnormal functioning of the anterior cingulate cortex (ACC) during tasks involving selective attention. In other respects, there is mounting evidence that neurofeedback training (NFT) can significantly improve cognitive functioning in AD/HD children. In this context, the present functional magnetic resonance imaging (fMRI) study was conducted to measure the effect of NFT on the neural substrates of selective attention in children with AD/HD. Twenty AD/HD children--not taking any psychostimulant and without co-morbidity-participated to the study. Fifteen children were randomly assigned to the Experimental (EXP) group (NFT), whereas the other five children were assigned to the Control (CON) group (no NFT). Subjects from both groups were scanned 1 week before the beginning of the NFT (Time 1) and 1 week after the end of this training (Time 2), while they performed a Counting Stroop task. At Time 1, for both groups, the Counting Stroop task was associated with significant loci of activation in the left superior parietal lobule. No activation was noted in the ACC. At Time 2, for both groups, the Counting Stroop task was still associated with significant activation of the left superior parietal lobule. This time, however, for the EXP group only there was a significant activation of the right ACC. These results suggest that in AD/HD children, NFT has the capacity to normalize the functioning of the ACC, the key neural substrate of selective attention.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/psicología , Atención/fisiología , Biorretroalimentación Psicológica , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Mapeo Encefálico , Corteza Cerebral/fisiopatología , Niño , Femenino , Lateralidad Funcional/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Desempeño Psicomotor/fisiología
12.
Clin EEG Neurosci ; 47(1): 37-47, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25550444

RESUMEN

Three-dimensional multiple object tracking (3D-MOT) is a perceptual-cognitive training system based on a 3D virtual environment. This is the first study to examine the effects of 3D-MOT training on attention, working memory, and visual information processing speed as well as using functional brain imaging on a normative population. Twenty university-aged students were recruited and divided into a training (NT) and nonactive control (CON) group. Cognitive functions were assessed using neuropsychological tests, and correlates of brain functions were assessed using quantitative electroencephalography (qEEG). Results indicate that 10 sessions of 3D-MOT training can enhance attention, visual information processing speed, and working memory, and also leads to quantifiable changes in resting-state neuroelectric brain function.


Asunto(s)
Atención/fisiología , Encéfalo/fisiología , Cognición/fisiología , Práctica Psicológica , Desempeño Psicomotor/fisiología , Percepción Espacial/fisiología , Adulto , Mapeo Encefálico/métodos , Femenino , Humanos , Masculino , Memoria a Corto Plazo/fisiología , Procesamiento Espacial/fisiología , Adulto Joven
13.
Artículo en Inglés | MEDLINE | ID: mdl-15610941

RESUMEN

This study investigated changes in cerebral activation related to emotion processing in schizophrenia patients with blunted or flat affect (FA+) during treatment with quetiapine. Using functional magnetic resonance imaging (fMRI), brain activation in 12 FA+ schizophrenia patients during passive viewing of sad film excerpts was studied before and after a median of 5.5-months treatment with quetiapine. Random-effects 'paired sample t-test' analyses of brain activation before quetiapine (contrast=sad-neutral, before-after) revealed significant activation in the brainstem (pons, medulla). After quetiapine, the same contrast showed significant prefrontal activation (BA 9, 10 and 11). Activation of key prefrontal areas involved in emotion processing and significant symptoms improvement as measured by the subjective rating scale and PANSS suggests the potential effect of quetiapine in improving blunted affect related symptoms (i.e., passive withdrawal, emotional withdrawal, social avoidance) in schizophrenia.


Asunto(s)
Afecto/fisiología , Antipsicóticos/uso terapéutico , Dibenzotiazepinas/uso terapéutico , Lóbulo Frontal/fisiopatología , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/fisiopatología , Psicología del Esquizofrénico , Adulto , Afecto/efectos de los fármacos , Imagen Eco-Planar , Emociones/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Escalas de Valoración Psiquiátrica , Fumarato de Quetiapina
14.
Psychiatry Res ; 140(1): 1-15, 2005 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-16143498

RESUMEN

The aim of this functional magnetic resonance imaging (fMRI) study was to compare regional brain activity in schizophrenia subjects with (FA+) and without (FA-) flat affect during the viewing of emotionally negative pictures. Thirteen FA+ subjects and 11 FA- subjects were scanned while being presented with a series of emotionally negative and neutral pictures. Experientially, the viewing of the negative pictures induced a negative emotional state whose intensity was significantly greater in the FA- group than in the FA+ group. Neurally, the Negative minus Neutral contrast revealed, in the FA- group, significant loci of activation in the midbrain, pons, anterior cingulate cortex, insula, ventrolateral orbitofrontal cortex, anterior temporal pole, amygdala, medial prefrontal cortex, and extrastriate visual cortex. In the FA+ group, this contrast produced significant loci of activation in the midbrain, pons, anterior temporal pole, and extrastriate visual cortex. When the brain activity measured in the FA+ group was subtracted from that measured in the FA- group, only the lingual gyrus was significantly activated. Perhaps in FA+ subjects an amygdaloid malfunction rendered the amygdala unable to correctly evaluate the emotional meaning of the pictures presented, thus preventing effective connectivity linking the amygdala to the brain regions implicated in the physiological and experiential dimensions of emotion. Alternatively, a disturbance of effective connectivity in the neural networks linking the midbrain and the medial prefrontal system may have been responsible for the quasi absence of emotional reaction in FA+ subjects, and the abnormal functioning of the medial prefrontal cortex and anterior cingulate cortex in the FA+ group.


Asunto(s)
Afecto , Encéfalo/metabolismo , Encéfalo/fisiopatología , Imagen por Resonancia Magnética , Estimulación Luminosa , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatología , Adulto , Amígdala del Cerebelo/metabolismo , Encéfalo/anatomía & histología , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad
15.
Biol Psychiatry ; 53(6): 502-10, 2003 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-12644355

RESUMEN

BACKGROUND: The ability to voluntarily self-regulate negative emotion is essential to a healthy psyche. Indeed, a chronic incapacity to suppress negative emotion might be a key factor in the genesis of depression and anxiety. Regarding the neural underpinnings of emotional self-regulation, a recent functional neuroimaging study carried out by our group has revealed that the dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex are involved in voluntary suppression of sexual arousal. As few things are known, still, with respect to the neural substrate underlying volitional self-regulation of basic emotions, here we used functional magnetic resonance imaging to identify the neural circuitry associated with the voluntary suppression of sadness. METHODS: Twenty healthy female subjects were scanned during a Sad condition and a Suppression condition. In the Sad condition, subjects were instructed to react normally to sad film excerpts whereas, in the Suppression condition, they were asked to voluntarily suppress any emotional reaction in response to comparable stimuli. RESULTS: Transient sadness was associated with significant loci of activation in the anterior temporal pole and the midbrain, bilaterally, as well as in the left amygdala, left insula, and right ventrolateral prefrontal cortex (VLPFC) (Brodmann area [BA] 47). Correlational analyses carried out between self-report ratings of sadness and regional blood oxygen level dependent (BOLD) signal changes revealed the existence of positive correlations in the right VLPFC (BA 47), bilaterally, as well as in the left insula and the affective division of the left anterior cingulate gyrus (BA 24/32). In the Suppression condition, significant loci of activation were noted in the right DLPFC (BA 9) and the right orbitofrontal cortex (OFC) (BA 11), and positive correlations were found between the self-report ratings of sadness and BOLD signal changes in the right OFC (BA 11) and right DLPFC (BA 9). CONCLUSIONS: These results confirm the key role played by the DLPFC in emotional self-regulation. They also indicate that the right DLPFC and right OFC are components of a neural circuit implicated in voluntary suppression of sadness.


Asunto(s)
Afecto , Red Nerviosa/irrigación sanguínea , Controles Informales de la Sociedad , Adulto , Encéfalo/anatomía & histología , Encéfalo/irrigación sanguínea , Imagen Eco-Planar/instrumentación , Procesamiento Automatizado de Datos , Femenino , Humanos , Inhibición Neural/fisiología , Oxígeno/sangre
16.
Neuroreport ; 14(8): 1111-6, 2003 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-12821792

RESUMEN

The question of whether distinct or similar neural substrates underlie primary emotions has not been resolved yet. To address this issue, we used fMRI to scan professional actors during self-induced states of sadness and happiness. Results demonstrated that, relative to an emotionally Neutral state, both the Sad and the Happy states were associated with significant loci of activation, bilaterally, in the orbitofrontal cortex, and in the left medial prefrontal cortex, left ventrolateral prefrontal cortex, left anterior temporal pole, and right pons. These loci of activation were localized distinctly within these regions, that is, in different sub-regions. These results suggest that sadness and happiness may be associated with similar brain regions but distinct sub-regions and neural circuits.


Asunto(s)
Corteza Cerebral/fisiología , Ego , Emociones/fisiología , Vías Nerviosas/fisiología , Adulto , Mapeo Encefálico , Corteza Cerebral/anatomía & histología , Femenino , Humanos , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Radioisótopos de Oxígeno/farmacocinética
17.
Brain Lang ; 89(1): 9-20, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15010232

RESUMEN

The purpose of the present study was to compare the brain regions and systems that subserve lexical and sublexical processes in reading. In order to do so, three types of tasks were used: (i). silent reading of very high frequency regular words (lexical task); (ii). silent reading of nonwords (sublexical task); and, (iii). silent reading of very low frequency regular words (sublexical task). All three conditions were contrasted with a visual/phonological baseline condition. The lexical condition engaged primarily an area at the border of the left angular and supramarginal gyri. Activation found in this region suggests that this area may be involved in mapping orthographic-to-phonological whole word representations. Both sublexical conditions elicited significantly greater activation in the left inferior prefrontal gyrus. This region is thought to be associated with sublexical processes in reading such as grapheme-to-phoneme conversion, phoneme assembly and underlying verbal working memory processes. Activation in the left IFG was also associated with left superior and middle temporal activation. These areas are thought to be functionally correlated with the left IFG and to contribute to a phonologically based form of reading. The results as a whole demonstrate that lexical and sublexical processes in reading activate different regions within a complex network of brain structures.


Asunto(s)
Corteza Cerebral/fisiología , Aumento de la Imagen , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Imagen por Resonancia Magnética , Fonación/fisiología , Lectura , Semántica , Adulto , Mapeo Encefálico , Cerebelo/fisiología , Dominancia Cerebral/fisiología , Humanos , Masculino , Red Nerviosa/fisiología , Oxígeno/sangre , Aprendizaje Verbal/fisiología
18.
Dialogues Clin Neurosci ; 16(1): 75-81, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24733972

RESUMEN

It has been long established that psychological interventions can markedly alter patients' thinking patterns, beliefs, attitudes, emotional states, and behaviors. Little was known about the neural mechanisms mediating such alterations before the advent of functional neuroimaging techniques. Since the turn of the new millenium, several functional neuroimaging studies have been conducted to tackle this important issue. Some of these studies have explored the neural impact of various forms of psychotherapy in individuals with major depressive disorder. Other neuroimaging studies have investigated the effects of psychological interventions for anxiety disorders. I review these studies in the present article, and discuss the putative neural mechanisms of change in psychotherapy. The findings of these studies suggest that mental and behavioral changes occurring during psychotherapeutic interventions can lead to a normalization of functional brain activity at a global level.


Desde hace tiempo se ha establecido que las intervenciones psicológicas pueden alterar marcadamente los patrones del pensamiento, las creencias, las actitudes, los estados emocionales y las conductas de los pacientes. Previo a la incorporación de las técnicas de neuroimágenes funcionales se conocía poco sobre los mecanismos neurales que mediaban estas alteraciones. Desde el comienzo del nuevo milenio se han realizado algunos estudios de neuroimágenes funcionales para abordar este importante tema. Algunos de ellos han explorado el impacto neural de diferentes formas de psicoterapia en sujetos con trastorno depresivo mayor. Otros estudios han investigado los efectos de las íntervenciones psicológicas en los trastornos ansiosos. En este artículo se revisan estos estudios y se discuten los mecanismos neurales de cambio reconocidos en la psicoterapia. Los hallazgos de estos estudios sugieren que los cambios mentales y conductuales que se producen durante las intervenciones psicoterapéuticas pueden llevar a una normalización de la actividad cerebral funcional a nivel global.


Les interventions psychologiques sont connues depuis longtemps pour leur capacité à nettement modifier les schémas de pensée, les croyances, les attitudes, les états émotionnels et les comportements des patients. Avant l'ère des techniques de neuro-imagerie fonctionnelle, les mécanismes neuronaux liés à ces troubles étaient peu connus. Depuis ce nouveau millénaire, plusieurs études de neuro-imagerie fonctionnelle ont été conduites pour aborder cette importante question. Certaines d'entre elles ont examiné l'impact neuronal de différentes formes de psychothérapie chez des patients ayant un épisode dépressif caractérisé. D'autres ont analysé les effets des actions psychologiques sur les troubles anxieux. Dans cet article, j'examine ces études et j'analyse les mécanismes neuronaux présumés du changement en psychothérapie. Leurs résultats suggèrent que les modifications mentales et comportementales intervenant pendant les psychothérapies peuvent conduire à une normalisation de l'activité cérébrale fonctionnelle à un niveau global.


Asunto(s)
Encéfalo/fisiología , Neuroimagen Funcional , Psicoterapia , Humanos
19.
Clin EEG Neurosci ; 44(4): 265-72, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23536382

RESUMEN

The main objective of this structural magnetic resonance imaging (MRI) study was to investigate, using diffusion tensor imaging, whether a neurofeedback training (NFT) protocol designed to improve sustained attention might induce structural changes in white matter (WM) pathways, purportedly implicated in this cognitive ability. Another goal was to examine whether gray matter (GM) volume (GMV) might be altered following NFT in frontal and parietal cortical areas connected by these WM fiber pathways. Healthy university students were randomly assigned to an experimental group (EXP), a sham group, or a control group. Participants in the EXP group were trained to enhance the amplitude of their ß1 waves at F4 and P4. Measures of attentional performance and MRI data were acquired one week before (Time 1) and one week after (Time 2) NFT. Higher scores on visual and auditory sustained attention were noted in the EXP group at Time 2 (relative to Time 1). As for structural MRI data, increased fractional anisotropy was measured in WM pathways implicated in sustained attention, and GMV increases were detected in cerebral structures involved in this type of attention. After 50 years of research in the field of neurofeedback, our study constitutes the first empirical demonstration that NFT can lead to microstructural changes in white and gray matter.


Asunto(s)
Atención/fisiología , Corteza Cerebral/citología , Corteza Cerebral/fisiología , Electroencefalografía/métodos , Fibras Nerviosas Mielínicas/ultraestructura , Neurorretroalimentación/métodos , Neuronas/citología , Adolescente , Adulto , Femenino , Humanos , Masculino , Fibras Nerviosas Mielínicas/fisiología , Plasticidad Neuronal/fisiología , Neuronas/fisiología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
20.
Soc Cogn Affect Neurosci ; 8(1): 4-14, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22446298

RESUMEN

Mindfulness meditation has been shown to promote emotional stability. Moreover, during the processing of aversive and self-referential stimuli, mindful awareness is associated with reduced medial prefrontal cortex (MPFC) activity, a central default mode network (DMN) component. However, it remains unclear whether mindfulness practice influences functional connectivity between DMN regions and, if so, whether such impact persists beyond a state of meditation. Consequently, this study examined the effect of extensive mindfulness training on functional connectivity within the DMN during a restful state. Resting-state data were collected from 13 experienced meditators (with over 1000 h of training) and 11 beginner meditators (with no prior experience, trained for 1 week before the study) using functional magnetic resonance imaging (fMRI). Pairwise correlations and partial correlations were computed between DMN seed regions' time courses and were compared between groups utilizing a Bayesian sampling scheme. Relative to beginners, experienced meditators had weaker functional connectivity between DMN regions involved in self-referential processing and emotional appraisal. In addition, experienced meditators had increased connectivity between certain DMN regions (e.g. dorso-medial PFC and right inferior parietal lobule), compared to beginner meditators. These findings suggest that meditation training leads to functional connectivity changes between core DMN regions possibly reflecting strengthened present-moment awareness.


Asunto(s)
Atención/fisiología , Concienciación/fisiología , Meditación/métodos , Red Nerviosa/fisiología , Corteza Prefrontal/fisiología , Adaptación Psicológica/fisiología , Adulto , Mapeo Encefálico/métodos , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Práctica Psicológica , Autoimagen
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