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1.
Radiology ; 310(2): e231143, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38349241

RESUMEN

Background Cognitive behavioral therapy (CBT) is the current standard treatment for chronic severe tinnitus; however, preliminary evidence suggests that real-time functional MRI (fMRI) neurofeedback therapy may be more effective. Purpose To compare the efficacy of real-time fMRI neurofeedback against CBT for reducing chronic tinnitus distress. Materials and Methods In this prospective controlled trial, participants with chronic severe tinnitus were randomized from December 2017 to December 2021 to receive either CBT (CBT group) for 10 weekly group sessions or real-time fMRI neurofeedback (fMRI group) individually during 15 weekly sessions. Change in the Tinnitus Handicap Inventory (THI) score (range, 0-100) from baseline to 6 or 12 months was assessed. Secondary outcomes included four quality-of-life questionnaires (Beck Depression Inventory, Pittsburgh Sleep Quality Index, State-Trait Anxiety Inventory, and World Health Organization Disability Assessment Schedule). Questionnaire scores between treatment groups and between time points were assessed using repeated measures analysis of variance and the nonparametric Wilcoxon signed rank test. Results The fMRI group included 21 participants (mean age, 49 years ± 11.4 [SD]; 16 male participants) and the CBT group included 22 participants (mean age, 53.6 years ± 8.8; 16 male participants). The fMRI group showed a greater reduction in THI scores compared with the CBT group at both 6 months (mean score change, -28.21 points ± 18.66 vs -12.09 points ± 18.86; P = .005) and 12 months (mean score change, -30 points ± 25.44 vs -4 points ± 17.2; P = .01). Compared with baseline, the fMRI group showed improved sleep (mean score, 8.62 points ± 4.59 vs 7.25 points ± 3.61; P = .006) and trait anxiety (mean score, 44 points ± 11.5 vs 39.84 points ± 10.5; P = .02) at 1 month and improved depression (mean score, 13.71 points ± 9.27 vs 6.53 points ± 5.17; P = .01) and general functioning (mean score, 24.91 points ± 17.05 vs 13.06 points ± 10.1; P = .01) at 6 months. No difference in these metrics over time was observed for the CBT group (P value range, .14 to >.99). Conclusion Real-time fMRI neurofeedback therapy led to a greater reduction in tinnitus distress than the current standard treatment of CBT. ClinicalTrials.gov registration no.: NCT05737888; Swiss Ethics registration no.: BASEC2017-00813 © RSNA, 2024 Supplemental material is available for this article.


Asunto(s)
Terapia Cognitivo-Conductual , Neurorretroalimentación , Acúfeno , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Acúfeno/diagnóstico por imagen , Acúfeno/terapia , Imagen por Resonancia Magnética
2.
Front Hum Neurosci ; 16: 933559, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36092645

RESUMEN

Most clinical neurofeedback studies based on functional magnetic resonance imaging use the patient's own neural activity as feedback. The objective of this study was to create a subject-independent brain state classifier as part of a real-time fMRI neurofeedback (rt-fMRI NF) system that can guide patients with depression in achieving a healthy brain state, and then to examine subsequent clinical changes. In a first step, a brain classifier based on a support vector machine (SVM) was trained from the neural information of happy autobiographical imagery and motor imagery blocks received from a healthy female participant during an MRI session. In the second step, 7 right-handed female patients with mild or moderate depressive symptoms were trained to match their own neural activity with the neural activity corresponding to the "happiness emotional brain state" of the healthy participant. The training (4 training sessions over 2 weeks) was carried out using the rt-fMRI NF system guided by the brain-state classifier we had created. Thus, the informative voxels previously obtained in the first step, using SVM classification and Effect Mapping, were used to classify the Blood-Oxygen-Level Dependent (BOLD) activity of the patients and converted into real-time visual feedback during the neurofeedback training runs. Improvements in the classifier accuracy toward the end of the training were observed in all the patients [Session 4-1 Median = 6.563%; Range = 4.10-27.34; Wilcoxon Test (0), 2-tailed p = 0.031]. Clinical improvement also was observed in a blind standardized clinical evaluation [HDRS CE2-1 Median = 7; Range 2 to 15; Wilcoxon Test (0), 2-tailed p = 0.016], and in self-report assessments [BDI-II CE2-1 Median = 8; Range 1-15; Wilcoxon Test (0), 2-tailed p = 0.031]. In addition, the clinical improvement was still present 10 days after the intervention [BDI-II CE3-2_Median = 0; Range -1 to 2; Wilcoxon Test (0), 2-tailed p = 0.50/ HDRS CE3-2 Median = 0; Range -1 to 2; Wilcoxon Test (0), 2-tailed p = 0.625]. Although the number of participants needs to be increased and a control group included to confirm these findings, the results suggest a novel option for neural modulation and clinical alleviation in depression using noninvasive stimulation technologies.

3.
J Neural Eng ; 18(5)2021 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-34587606

RESUMEN

Objective.Brain-computer interface (BCI) is a tool that can be used to train brain self-regulation and influence specific activity patterns, including functional connectivity, through neurofeedback. The functional connectivity of the primary motor area (M1) and cerebellum play a critical role in motor recovery after a brain injury, such as stroke. The objective of this study was to determine the feasibility of achieving control of the functional connectivity between M1 and the cerebellum in healthy subjects. Additionally, we aimed to compare the brain self-regulation of two different feedback modalities and their effects on motor performance.Approach.Nine subjects were trained with a real-time functional magnetic resonance imaging BCI system. Two groups were conformed: equal feedback group (EFG), which received neurofeedback that weighted the contribution of both regions of interest (ROIs) equally, and weighted feedback group (WFG) that weighted each ROI differentially (30% cerebellum; 70% M1). The magnitude of the brain activity induced by self-regulation was evaluated with the blood-oxygen-level-dependent (BOLD) percent change (BPC). Functional connectivity was assessed using temporal correlations between the BOLD signal of both ROIs. A finger-tapping task was included to evaluate the effect of brain self-regulation on motor performance.Main results.A comparison between the feedback modalities showed that WFG achieved significantly higher BPC in M1 than EFG. The functional connectivity between ROIs during up-regulation in WFG was significantly higher than EFG. In general, both groups showed better tapping speed in the third session compared to the first. For WFG, there were significant correlations between functional connectivity and tapping speed.Significance.The results show that it is possible to train healthy individuals to control M1-cerebellum functional connectivity with rtfMRI-BCI. Besides, it is also possible to use a weighted feedback approach to facilitate a higher activity of one region over another.


Asunto(s)
Corteza Motora , Neurorretroalimentación , Autocontrol , Cerebelo , Humanos , Imagen por Resonancia Magnética
4.
J Vis Exp ; (160)2020 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-32597838

RESUMEN

It has been more than a decade since the first functional magnetic resonance imaging (fMRI)-based neurofeedback approach was successfully implemented. Since then, various studies have demonstrated that participants can learn to voluntarily control a circumscribed brain region. Consequently, real-time fMRI (rtfMRI) provided a novel opportunity to study modifications of behavior due to manipulation of brain activity. Hence, reports of rtfMRI applications to train self-regulation of brain activity and the concomitant modifications in behavioral and clinical conditions such as neurological and psychiatric disorders [e.g., schizophrenia, obsessive compulsive Disorder (OCD), stroke] have rapidly increased. Neuroimaging studies in addiction research have shown that the anterior cingulate cortex, orbitofrontal cortex, and insular cortex are activated during the presentation of drug-associated cues. Also, activity in both left and right insular cortices have been shown to be highly correlated with drug urges when participants are exposed to craving-eliciting cues. Hence, the bilateral insula is of particular importance in researching drug urges and addiction due to its role in the representation of bodily (interoceptive) states. This study explores the use of rtfMRI neurofeedback for the reduction in blood oxygen-level dependent (BOLD) activity in bilateral insular cortices of nicotine-addicted participants. The study also tests if there are neurofeedback training-associated modifications in the implicit attitudes of participants towards nicotine-craving cues and explicit-craving behavior.


Asunto(s)
Corteza Cerebral/diagnóstico por imagen , Regulación hacia Abajo , Imagen por Resonancia Magnética , Neurorretroalimentación , Nicotina/efectos adversos , Fumadores , Tabaquismo/diagnóstico por imagen , Tabaquismo/fisiopatología , Corteza Cerebral/fisiopatología , Ansia/fisiología , Estudios de Seguimiento , Humanos , Oxígeno/sangre , Encuestas y Cuestionarios
5.
Brain ; 143(6): 1674-1685, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32176800

RESUMEN

Neurofeedback has begun to attract the attention and scrutiny of the scientific and medical mainstream. Here, neurofeedback researchers present a consensus-derived checklist that aims to improve the reporting and experimental design standards in the field.


Asunto(s)
Lista de Verificación/métodos , Neurorretroalimentación/métodos , Adulto , Consenso , Femenino , Humanos , Masculino , Persona de Mediana Edad , Revisión de la Investigación por Pares , Proyectos de Investigación/normas , Participación de los Interesados
6.
Brain Connect ; 9(8): 613-626, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31353935

RESUMEN

Stroke lesions in the language centers of the brain impair the language areas and their connectivity. This article describes the dynamics of functional connectivity (FC) of language areas (FCL) during real-time functional magnetic resonance imaging (RT-fMRI)-based neurofeedback training for poststroke patients with expressive aphasia. The hypothesis is that FCL increases during the upregulation of language areas during neurofeedback training and that the training improves FCL with an increasing number of sessions and restores it toward normalcy. Four test and four control patients with expressive aphasia were recruited for the study along with four healthy volunteers termed as the normal group. The test and normal groups were administered four neurofeedback training sessions in between two test sessions, whereas the control group underwent only the two test sessions. The training session requires the subject to exercise language activity covertly so that it upregulates the feedback signal obtained from the Broca's area (in left inferior frontal gyrus) and amplifies the feedback when it is correlated with the Wernicke's area (in left superior temporal gyrus) using RT-fMRI. FC was measured by Pearson's correlation coefficient. The results indicate that the FC of the test group was weaker in the left hemisphere than that of the normal group, and post-training the connections have strengthened (correlation coefficient increases) in the left hemisphere when compared with the control group. The connections of language areas strengthened in both hemispheres during neurofeedback-based upregulation, and multiple training sessions strengthened new pathways and restored left hemispheric connections toward normalcy.


Asunto(s)
Afasia de Broca/terapia , Encéfalo/fisiopatología , Lenguaje , Imagen por Resonancia Magnética , Neurorretroalimentación , Accidente Cerebrovascular/terapia , Afasia de Broca/diagnóstico por imagen , Afasia de Broca/etiología , Afasia de Broca/fisiopatología , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Humanos , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/fisiopatología , Resultado del Tratamiento
7.
Brain Cogn ; 131: 10-21, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30502227

RESUMEN

BACKGROUND: Functional connectivity (fcMRI) analyses of resting state functional magnetic resonance imaging (fMRI) data revealed substantial differences between states of consciousness. The underlying cause-effect linkage, however, remains unknown to the present day. The aim of this study was to examine the relationship between fcMRI measures and Disorders of Consciousness (DOC) in resting state and under adequate stimulation. METHODS AND FINDINGS: fMRI data from thirteen patients with unresponsive wakefulness syndrome, eight patients in minimally conscious state, and eleven healthy controls were acquired in rest and during the application of nociceptive and emotional acoustic stimuli. We compared spatial characteristics and anatomical topography of seed-based fcMRI networks on group and individual levels. The anatomical topography of fcMRI networks of patients was altered in all three conditions as compared with healthy controls. Spread and distribution of individual fcMRI networks, however, differed significantly between patients and healthy controls in stimulation conditions only. The exploration of individual metric values identified two patients whose spatial metrics did not deviate from metric distributions of healthy controls in a statistically meaningful manner. CONCLUSIONS: These findings suggest that the disturbance of consciousness in DOC is related to deficits in global topographical network organization rather than a principal inability to establish long-distance connections. In addition, the results question the claim that task-free measurements are particularly valuable as a tool for individual diagnostics in severe neurological disorders. Further studies comparing connectivity indices with outcome of DOC patients are needed to determine the clinical relevance of spatial metrics and stimulation paradigms for individual diagnosis, prognosis and treatment in DOC.


Asunto(s)
Encéfalo/diagnóstico por imagen , Trastornos de la Conciencia/diagnóstico por imagen , Estado de Conciencia/fisiología , Red Nerviosa/diagnóstico por imagen , Estimulación Acústica , Adolescente , Adulto , Anciano , Encéfalo/fisiopatología , Trastornos de la Conciencia/fisiopatología , Electroencefalografía , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Red Nerviosa/fisiopatología , Descanso , Adulto Joven
8.
Hum Brain Mapp ; 38(9): 4353-4369, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28580720

RESUMEN

Bimanual movements involve the interactions between both primary motor cortices. These interactions are assumed to involve phase-locked oscillatory brain activity referred to as inter-hemispheric functional coupling. So far, inter-hemispheric functional coupling has been investigated as a function of motor performance. These studies report mostly a negative correlation between the performance in motor tasks and the strength of functional coupling. However, correlation might not reflect a causal relationship. To overcome this limitation, we opted for an alternative approach by manipulating the strength of inter-hemispheric functional coupling and assessing bimanual motor performance as a dependent variable. We hypothesize that an increase/decrease of functional coupling deteriorates/facilitates motor performance in an out-of-phase bimanual finger-tapping task. Healthy individuals were trained to volitionally regulate functional coupling in an operant conditioning paradigm using real-time magnetoencephalography neurofeedback. During operant conditioning, two discriminative stimuli were associated with upregulation and downregulation of functional coupling. Effects of training were assessed by comparing motor performance prior to (pre-test) and after the training (post-test). Participants receiving contingent feedback learned to upregulate and downregulate functional coupling. Comparing motor performance, as indexed by the ratio of tapping speed for upregulation versus downregulation trials, no change was found in the control group between pre- and post-test. In contrast, the group receiving contingent feedback evidenced a significant decrease of the ratio implicating lower tapping speed with stronger functional coupling. Results point toward a causal role of inter-hemispheric functional coupling for the performance in bimanual tasks. Hum Brain Mapp 38:4353-4369, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Lateralidad Funcional/fisiología , Mano/fisiología , Aprendizaje/fisiología , Corteza Motora/fisiología , Destreza Motora/fisiología , Neurorretroalimentación , Adulto , Condicionamiento Operante/fisiología , Femenino , Humanos , Magnetoencefalografía/métodos , Masculino , Neurorretroalimentación/métodos , Neurorretroalimentación/fisiología , Plasticidad Neuronal/fisiología , Volición
9.
Nat Rev Neurosci ; 18(2): 86-100, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28003656

RESUMEN

Neurofeedback is a psychophysiological procedure in which online feedback of neural activation is provided to the participant for the purpose of self-regulation. Learning control over specific neural substrates has been shown to change specific behaviours. As a progenitor of brain-machine interfaces, neurofeedback has provided a novel way to investigate brain function and neuroplasticity. In this Review, we examine the mechanisms underlying neurofeedback, which have started to be uncovered. We also discuss how neurofeedback is being used in novel experimental and clinical paradigms from a multidisciplinary perspective, encompassing neuroscientific, neuroengineering and learning-science viewpoints.


Asunto(s)
Encéfalo/fisiología , Aprendizaje/fisiología , Neurorretroalimentación/fisiología , Animales , Trastorno por Déficit de Atención con Hiperactividad/terapia , Humanos , Neuroimagen/métodos , Plasticidad Neuronal/fisiología , Autocontrol , Rehabilitación de Accidente Cerebrovascular/métodos
10.
PLoS One ; 11(7): e0159959, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27467528

RESUMEN

Recently, studies have reported the use of Near Infrared Spectroscopy (NIRS) for developing Brain-Computer Interface (BCI) by applying online pattern classification of brain states from subject-specific fNIRS signals. The purpose of the present study was to develop and test a real-time method for subject-specific and subject-independent classification of multi-channel fNIRS signals using support-vector machines (SVM), so as to determine its feasibility as an online neurofeedback system. Towards this goal, we used left versus right hand movement execution and movement imagery as study paradigms in a series of experiments. In the first two experiments, activations in the motor cortex during movement execution and movement imagery were used to develop subject-dependent models that obtained high classification accuracies thereby indicating the robustness of our classification method. In the third experiment, a generalized classifier-model was developed from the first two experimental data, which was then applied for subject-independent neurofeedback training. Application of this method in new participants showed mean classification accuracy of 63% for movement imagery tasks and 80% for movement execution tasks. These results, and their corresponding offline analysis reported in this study demonstrate that SVM based real-time subject-independent classification of fNIRS signals is feasible. This method has important applications in the field of hemodynamic BCIs, and neuro-rehabilitation where patients can be trained to learn spatio-temporal patterns of healthy brain activity.


Asunto(s)
Interfaces Cerebro-Computador , Movimiento , Espectroscopía Infrarroja Corta/métodos , Biorretroalimentación Psicológica , Humanos
11.
Hum Brain Mapp ; 37(9): 3153-71, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27272616

RESUMEN

The learning process involved in achieving brain self-regulation is presumed to be related to several factors, such as type of feedback, reward, mental imagery, duration of training, among others. Explicitly instructing participants to use mental imagery and monetary reward are common practices in real-time fMRI (rtfMRI) neurofeedback (NF), under the assumption that they will enhance and accelerate the learning process. However, it is still not clear what the optimal strategy is for improving volitional control. We investigated the differential effect of feedback, explicit instructions and monetary reward while training healthy individuals to up-regulate the blood-oxygen-level dependent (BOLD) signal in the supplementary motor area (SMA). Four groups were trained in a two-day rtfMRI-NF protocol: GF with NF only, GF,I with NF + explicit instructions (motor imagery), GF,R with NF + monetary reward, and GF,I,R with NF + explicit instructions (motor imagery) + monetary reward. Our results showed that GF increased significantly their BOLD self-regulation from day-1 to day-2 and GF,R showed the highest BOLD signal amplitude in SMA during the training. The two groups who were instructed to use motor imagery did not show a significant learning effect over the 2 days. The additional factors, namely motor imagery and reward, tended to increase the intersubject variability in the SMA during the course of training. Whole brain univariate and functional connectivity analyses showed common as well as distinct patterns in the four groups, representing the varied influences of feedback, reward, and instructions on the brain. Hum Brain Mapp 37:3153-3171, 2016. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Encéfalo/fisiología , Imágenes en Psicoterapia/métodos , Aprendizaje/fisiología , Neurorretroalimentación/métodos , Recompensa , Adolescente , Adulto , Mapeo Encefálico , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
12.
Neurorehabil Neural Repair ; 30(7): 671-5, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26671217

RESUMEN

BACKGROUND: Two thirds of stroke survivors experience motor impairment resulting in long-term disability. The anatomical substrate is often the disruption of cortico-subcortical pathways. It has been proposed that reestablishment of cortico-subcortical communication relates to functional recovery. OBJECTIVE: In this study, we applied a novel training protocol to augment ipsilesional cortico-subcortical connectivity after stroke. Chronic stroke patients with severe motor impairment were provided online feedback of blood-oxygenation level dependent signal connectivity between cortical and subcortical regions critical for motor function using real-time functional magnetic resonance imaging neurofeedback. RESULTS: In this proof of principle study, 3 out of 4 patients learned to voluntarily modulate cortico-subcortical connectivity as intended. CONCLUSIONS: Our results document for the first time the feasibility and safety for patients with chronic stroke and severe motor impairment to self-regulate and augment ipsilesional cortico-subcortical connectivity through neurofeedback using real-time functional magnetic resonance imaging.


Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Vías Nerviosas/diagnóstico por imagen , Neurorretroalimentación/métodos , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/diagnóstico por imagen , Adulto , Interfaces Cerebro-Computador , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Sistemas en Línea , Oxígeno/sangre
13.
Biol Psychol ; 95: 4-20, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23643926

RESUMEN

With the advent of brain computer interfaces based on real-time fMRI (rtfMRI-BCI), the possibility of performing neurofeedback based on brain hemodynamics has become a reality. In the early stage of the development of this field, studies have focused on the volitional control of activity in circumscribed brain regions. However, based on the understanding that the brain functions by coordinated activity of spatially distributed regions, there have recently been further developments to incorporate real-time feedback of functional connectivity and spatio-temporal patterns of brain activity. The present article reviews the principles of rtfMRI neurofeedback, its applications, benefits and limitations. A special emphasis is given to the discussion of novel developments that have enabled the use of this methodology to achieve self-regulation of the functional connectivity between different brain areas and of distributed brain networks, anticipating new and exciting applications for cognitive neuroscience and for the potential alleviation of neuropsychiatric disorders.


Asunto(s)
Interfaces Cerebro-Computador , Encéfalo/fisiología , Imagen por Resonancia Magnética/métodos , Red Nerviosa/fisiología , Neurorretroalimentación , Neuronas/fisiología , Mapeo Encefálico , Humanos , Procesamiento de Imagen Asistido por Computador , Controles Informales de la Sociedad
14.
Neuroimage ; 83: 817-25, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23791838

RESUMEN

The dopaminergic system is involved in reward encoding and reinforcement learning. Dopaminergic neurons from this system in the substantia nigra/ventral tegmental area complex (SN/VTA) fire in response to unexpected reinforcing cues. The goal of this study was to investigate whether individuals can gain voluntary control of SN/VTA activity, thereby potentially enhancing dopamine release to target brain regions. Neurofeedback and mental imagery were used to self-regulate the SN/VTA. Real-time functional magnetic resonance imaging (rtfMRI) provided abstract visual feedback of the SN/VTA activity while the subject imagined rewarding scenes. Skin conductance response (SCR) was recorded as a measure of emotional arousal. To examine the effect of neurofeedback, subjects were assigned to either receiving feedback directly proportional (n=15, veridical feedback) or inversely proportional (n=17, inverted feedback) to SN/VTA activity. Both groups of subjects were able to up-regulate SN/VTA activity initially without feedback. Veridical feedback improved the ability to up-regulate SN/VTA compared to baseline while inverted feedback did not. Additional dopaminergic regions were activated in both groups. The ability to self-regulate SN/VTA was differentially correlated with SCR depending on the group, suggesting an association between emotional arousal and neurofeedback performance. These findings indicate that SN/VTA can be voluntarily activated by imagery and voluntary activation is further enhanced by neurofeedback. The findings may lead the way towards a non-invasive strategy for endogenous control of dopamine.


Asunto(s)
Neuronas Dopaminérgicas/fisiología , Mesencéfalo/fisiología , Neurorretroalimentación/fisiología , Adulto , Mapeo Encefálico , Humanos , Interpretación de Imagen Asistida por Computador , Imágenes en Psicoterapia , Imagen por Resonancia Magnética , Masculino , Recompensa , Adulto Joven
15.
Trends Cogn Sci ; 17(6): 295-302, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23664452

RESUMEN

Self-regulation and voluntary control of circumscribed brain regions using real-time functional MRI (rt-fMRI) allows the establishment of a causal functional link between localized brain activity and behavior and cognition. A long tradition of research has clearly shown the brain's ability to learn volitional control of its own activity and effects on behavior. Yet, the underlying neural mechanism of self-regulation is still not fully understood. Here, we propose that self-regulation of brain activity is akin to skill learning and thus may depend on an intact subcortical motor system. We elaborate on the critical role of the basal ganglia in skill learning and neurofeedback, and clarify that brain-self-regulation need not be an explicit and conscious process as often mistakenly held.


Asunto(s)
Mapeo Encefálico , Encéfalo/metabolismo , Aprendizaje/fisiología , Neurorretroalimentación , Animales , Encéfalo/irrigación sanguínea , Electroencefalografía , Potenciales Evocados , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Oxígeno , Controles Informales de la Sociedad
16.
Crit Rev Biomed Eng ; 41(3): 269-79, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24579648

RESUMEN

Brain-computer interfaces (BCIs) enable control of computers and other assistive devices, such as neuro-prostheses, which are used for communication, movement restoration, neuro-modulation, and muscle stimulation, by using only signals measured directly from the brain. A BCI creates a new output channel for the brain to a computer or a device. This requires retrieval of signals of interest from the brain, and its use for neuro-rehabilitation by means of interfacing the signals to a computerized device. Brain signals such as action potentials from single neurons or nerve fibers, extracellular local field potentials (LFPs), electrocorticograms, electroencephalogram and its components such as the event-related brain potentials, real-time functional magnetic resonance imaging, near-infrared spectroscopy, and magneto-encephalogram have been used. BCIs are envisaged to be useful for communication, control and self-regulation of brain function. BCIs employ neurofeedback to enable operant conditioning to allow the user to learn using it. Paralytic conditions arising from stroke or other diseases are being targeted for BCI application. Neurofeedback strategies ranging from sensory feedback to direct brain stimulation are being employed. Existing BCIs are limited in their throughput in terms of letters per minute or commands per minute, and need extensive training to use the BCI. Further, they can cause rapid fatigue due to use and have limited adaptability to changes in the patient's brain state. The challenge before BCI technology for neuro-rehabilitation today is to enable effective clinical use of BCIs with minimal effort to set up and operate.


Asunto(s)
Encefalopatías/rehabilitación , Interfaces Cerebro-Computador , Encéfalo/fisiología , Ingeniería Biomédica/métodos , Comunicación , Equipos de Comunicación para Personas con Discapacidad , Sistemas de Computación , Electrocardiografía/métodos , Electroencefalografía/métodos , Diseño de Equipo , Humanos , Imagen por Resonancia Magnética/métodos , Neurorretroalimentación , Espectroscopía Infrarroja Corta/métodos
17.
Hum Brain Mapp ; 34(1): 200-12, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22021045

RESUMEN

Real-time functional magnetic resonance imaging (rtfMRI) is a novel technique that has allowed subjects to achieve self-regulation of circumscribed brain regions. Despite its anticipated therapeutic benefits, there is no report on successful application of this technique in psychiatric populations. The objectives of the present study were to train schizophrenia patients to achieve volitional control of bilateral anterior insula cortex on multiple days, and to explore the effect of learned self-regulation on face emotion recognition (an extensively studied deficit in schizophrenia) and on brain network connectivity. Nine patients with schizophrenia were trained to regulate the hemodynamic response in bilateral anterior insula with contingent rtfMRI neurofeedback, through a 2-weeks training. At the end of the training stage, patients performed a face emotion recognition task to explore behavioral effects of learned self-regulation. A learning effect in self-regulation was found for bilateral anterior insula, which persisted through the training. Following successful self-regulation, patients recognized disgust faces more accurately and happy faces less accurately. Improvements in disgust recognition were correlated with levels of self-activation of right insula. RtfMRI training led to an increase in the number of the incoming and outgoing effective connections of the anterior insula. This study shows for the first time that patients with schizophrenia can learn volitional brain regulation by rtfMRI feedback training leading to changes in the perception of emotions and modulations of the brain network connectivity. These findings open the door for further studies of rtfMRI in severely ill psychiatric populations, and possible therapeutic applications.


Asunto(s)
Emociones/fisiología , Imagen por Resonancia Magnética/métodos , Neurorretroalimentación/métodos , Esquizofrenia/fisiopatología , Esquizofrenia/terapia , Volición/fisiología , Adulto , Mapeo Encefálico/métodos , Corteza Cerebral/citología , Corteza Cerebral/fisiología , Cara , Expresión Facial , Femenino , Humanos , Masculino , Modelos Neurológicos , Vías Nerviosas/fisiología , Reconocimiento Visual de Modelos/fisiología , Estimulación Luminosa/métodos , Reconocimiento en Psicología/fisiología , Adulto Joven
18.
Neuroscientist ; 18(5): 487-501, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21652587

RESUMEN

Real-time fMRI permits simultaneous measurement and observation of brain activity during an ongoing task. One of the most challenging applications of real-time fMRI in neuroscientific and clinical research is the possibility of acquiring volitional control of localized brain activity using real-time fMRI-based neurofeedback protocols. Real-time fMRI allows the experimenter to noninvasively manipulate brain activity as an independent variable to observe the effects on behavior. Real-time fMRI neurofeedback studies demonstrated that learned control of the local brain activity leads to specific changes in behavior. Here, the authors describe the implementation and application of real-time fMRI with particular emphasis on the self-regulation of local brain activity and the investigation of brain-function relationships. Real-time fMRI represents a promising new approach to cognitive neuroscience that could complement traditional neuroimaging techniques by providing more causal insights into the functional role of circumscribed brain regions in behavior.


Asunto(s)
Encéfalo/fisiología , Sistemas de Computación/normas , Condicionamiento Operante/fisiología , Neuroimagen Funcional/psicología , Imagen por Resonancia Magnética/psicología , Neurorretroalimentación/fisiología , Corteza Cerebral/fisiología , Imagen Eco-Planar/métodos , Imagen Eco-Planar/psicología , Neuroimagen Funcional/métodos , Neuroimagen Funcional/normas , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/normas , Neurorretroalimentación/métodos , Controles Informales de la Sociedad/métodos
19.
Soc Cogn Affect Neurosci ; 7(6): 623-34, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21983794

RESUMEN

Previous studies have shown that healthy participants learn to control local brain activity with operant training by using real-time functional magnetic resonance imaging (rt-fMRI). Very little data exist, however, on the dynamics of interaction between critical brain regions during rt-fMRI-based training. Here, we examined self-regulation of stimulus-elicited insula activation and performed a psychophysiological interaction (PPI) analysis of real-time self-regulation data. During voluntary up-regulation of the left anterior insula in the presence of threat-related pictures, differential activations were observed in the ventrolateral prefrontal cortex, the frontal operculum, the middle cingulate cortex and the right insula. Down-regulation in comparison to no-regulation revealed additional activations in right superior temporal cortex, right inferior parietal cortex and right middle frontal cortex. There was a significant learning effect over sessions during up-regulation, documented by a significant improvement of anterior insula control over time. Connectivity analysis revealed that successful up-regulation of the activity in left anterior insula while viewing aversive pictures was directly modulated by dorsomedial and ventrolateral prefrontal cortex. Down-regulation of activity was more difficult to achieve and no learning effect was observed. More extensive training might be necessary for successful down-regulation. These findings illustrate the functional interactions between different brain areas during regulation of anterior insula activity in the presence of threat-related stimuli.


Asunto(s)
Mapeo Encefálico , Emociones , Giro del Cíngulo/irrigación sanguínea , Giro del Cíngulo/fisiología , Aprendizaje/fisiología , Imagen por Resonancia Magnética , Adulto , Biorretroalimentación Psicológica , Femenino , Lateralidad Funcional , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Oxígeno/sangre , Estimulación Luminosa , Autoinforme , Factores de Tiempo , Adulto Joven
20.
Neurorehabil Neural Repair ; 26(3): 256-65, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21903976

RESUMEN

BACKGROUND: Despite the availability of various options for movement restoration in stroke patients, there is no effective treatment for patients who show little or no functional recovery of upper limb motor function. OBJECTIVE: The present study explored the feasibility of real-time functional magnetic resonance imaging brain-computer interface (fMRI-BCI) as a new tool for rehabilitation of this patient population. METHODS: Healthy adults and chronic subcortical stroke patients with residual movement were trained for 3 days to regulate the blood oxygenation level dependent (BOLD) response in the ventral premotor cortex (PMv), a secondary motor area with extensive anatomic connections with the primary motor cortex. Effect of learned modulation of the PMv was evaluated with BOLD signal changes across training sessions, transcranial magnetic stimulation (TMS), and a visuomotor task. RESULTS: fMRI-BCI feedback training showed learning with a significantly increasing BOLD signal in the PMv over sessions. Participants' capability to learn self-regulation was found to depend linearly on intracortical facilitation and correlated negatively with intracortical inhibition measured by TMS prior to feedback training. After training, intracortical inhibition decreased significantly with the volitional increase of the BOLD response in the PMv, indicating a beneficial effect of self-regulation training on motor cortical output. CONCLUSION: The study provides first evidence for the therapeutic potential of fMRI-BCI in stroke rehabilitation.


Asunto(s)
Biorretroalimentación Psicológica/métodos , Corteza Motora/irrigación sanguínea , Corteza Motora/fisiopatología , Paresia/patología , Paresia/rehabilitación , Interfaz Usuario-Computador , Potenciales Evocados Motores/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Inhibición Neural/fisiología , Oxígeno/sangre , Estimulación Luminosa , Desempeño Psicomotor , Estimulación Magnética Transcraneal
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