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1.
Dialogues Clin Neurosci ; 25(1): 33-42, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37190759

RESUMO

INTRODUCTION: Craving, involving intense and urgent desires to engage in specific behaviours, is a feature of addictions. Multiple studies implicate regions of salience/limbic networks and basal ganglia, fronto-parietal, medial frontal regions in craving in addictions. However, prior studies have not identified common neural networks that reliably predict craving across substance and behavioural addictions. METHODS: Functional magnetic resonance imaging during an audiovisual cue-reactivity task and connectome-based predictive modelling (CPM), a data-driven method for generating brain-behavioural models, were used to study individuals with cocaine-use disorder and gambling disorder. Functions of nodes and networks relevant to craving were identified and interpreted based on meta-analytic data. RESULTS: Craving was predicted by neural connectivity across disorders. The highest degree nodes were mostly located in the prefrontal cortex. Overall, the prediction model included complex networks including motor/sensory, fronto-parietal, and default-mode networks. The decoding revealed high functional associations with components of memory, valence ratings, physiological responses, and finger movement/motor imagery. CONCLUSIONS: Craving could be predicted across substance and behavioural addictions. The model may reflect general neural mechanisms of craving despite specificities of individual disorders. Prefrontal regions associated with working memory and autobiographical memory seem important in predicting craving. For further validation, the model should be tested in diverse samples and contexts.


Assuntos
Cocaína , Conectoma , Jogo de Azar , Transtornos Relacionados ao Uso de Substâncias , Humanos , Fissura/fisiologia , Jogo de Azar/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem
2.
Am J Psychiatry ; 180(6): 445-453, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36987598

RESUMO

OBJECTIVE: Craving is a central construct in the study of motivation and human behavior and is also a clinical symptom of substance and non-substance-related addictive disorders. Thus, craving represents a target for transdiagnostic modeling. METHODS: The authors applied connectome-based predictive modeling (CPM) to functional connectivity data in a large (N=274) transdiagnostic sample of individuals with and without substance use-related conditions, to predict self-reported craving. Functional connectomes derived from three guided imagery conditions of personalized appetitive, stress, and neutral-relaxing experiences were used to predict craving rated before and after each imagery condition. The generalizability of the "craving network" was tested in an independent sample using functional connectomes derived from a cue-induced craving task collected before and after fasting to predict craving rated during fasting. RESULTS: CPM successfully predicted craving, thereby identifying a transdiagnostic "craving network." Anatomical localization of model contribution suggested that the strongest predictors of craving were regions of the salience, subcortical, and default mode networks. As external validation, in an independent sample, the "craving network" predicted food craving during fasting using data from a cue-induced craving task. CONCLUSIONS: These data provide a transdiagnostic perspective to a key phenomenological feature of addictive disorders-craving-and identify a common "craving network" across individuals with and without substance use-related disorders, thereby suggesting a neural signature for craving or urge for motivated behaviors.


Assuntos
Comportamento Aditivo , Conectoma , Transtornos Relacionados ao Uso de Substâncias , Humanos , Fissura , Imageamento por Ressonância Magnética , Comportamento Aditivo/diagnóstico , Encéfalo/diagnóstico por imagem , Sinais (Psicologia)
3.
Neuroimage Clin ; 34: 102980, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35247729

RESUMO

BACKGROUND: Parkinson's disease (PD) causes difficulty with maintaining the speed, size, and vigor of movements, especially when they are internally generated. We previously proposed that the insula is important in motivating intentional movement via its connections with the dorsomedial frontal cortex (dmFC). We demonstrated that subjects with PD can increase the right insula-dmFC functional connectivity using fMRI-based neurofeedback (NF) combined with kinesthetic motor imagery (MI). The current study is a randomized clinical trial testing whether NF-guided kinesthetic MI training can improve motor performance and increase task-based and resting-state right insula-dmFC functional connectivity in subjects with PD. METHODS: We assigned nondemented subjects with mild PD (Hoehn & Yahr stage ≤ 3) to the experimental kinesthetic MI with NF (MI-NF, n = 22) and active control visual imagery (VI, n = 22) groups. Only the MI-NF group received NF-guided MI training (10-12 runs). The NF signal was based on the right insula-dmFC functional connectivity strength. All subjects also practiced their respective imagery tasks at home daily for 4 weeks. Post-training changes in 1) task-based and resting-state right insula-dmFC functional connectivity were the primary imaging outcomes, and 2) MDS-UPDRS motor exam and motor function scores were the primary and secondary clinical outcomes, respectively. RESULTS: The MI-NF group was not significantly different from the VI group in any of the primary imaging or clinical outcome measures. The MI-NF group reported subjective improvement in kinesthetic body awareness. There was significant and comparable improvement only in motor function scores in both groups (secondary clinical outcome). This improvement correlated with NF regulation of the right insula-dmFC functional connectivity only in the MI-NF group. Both groups showed specific training effects in whole-brain functional connectivity with distinct neural circuits supporting kinesthetic motor and visual imagery (exploratory imaging outcome). CONCLUSIONS: The functional connectivity-based NF regulation was unsuccessful, however, both kinesthetic MI and VI practice improved motor function in our cohort with mild PD.


Assuntos
Neurorretroalimentação , Doença de Parkinson , Mapeamento Encefálico , Humanos , Imagens, Psicoterapia , Imaginação/fisiologia , Cinestesia , Imageamento por Ressonância Magnética/métodos , Neurorretroalimentação/fisiologia , Doença de Parkinson/diagnóstico por imagem
4.
Nat Methods ; 17(12): 1262-1271, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33139894

RESUMO

Achieving a comprehensive understanding of brain function requires multiple imaging modalities with complementary strengths. We present an approach for concurrent widefield optical and functional magnetic resonance imaging. By merging these modalities, we can simultaneously acquire whole-brain blood-oxygen-level-dependent (BOLD) and whole-cortex calcium-sensitive fluorescent measures of brain activity. In a transgenic murine model, we show that calcium predicts the BOLD signal, using a model that optimizes a gamma-variant transfer function. We find consistent predictions across the cortex, which are best at low frequency (0.009-0.08 Hz). Furthermore, we show that the relationship between modality connectivity strengths varies by region. Our approach links cell-type-specific optical measurements of activity to the most widely used method for assessing human brain function.


Assuntos
Mapeamento Encefálico/métodos , Proteínas de Ligação ao Cálcio/metabolismo , Córtex Cerebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Animais , Gasometria , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Fluorescência , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Camundongos Transgênicos , Oxigênio/análise
5.
JAMA Netw Open ; 3(11): e2024661, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33141162

RESUMO

Importance: Higher maternal prepregnancy body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) is associated with adverse long-term outcomes for offspring, including obesity, poorer cognitive and social abilities, and increased risk of psychiatric disorders. Less clear is whether higher maternal BMI disrupts fetal growth and brain development. Objective: To investigate the association of maternal prepregnancy BMI with fetal growth and neonatal functional connectivity. Design, Setting, and Participants: This prospective longitudinal cohort study was conducted from 2012 to 2017. Participants included nulliparous pregnant adolescent and young adult women, aged 14 to 19 years who were recruited in the second trimester through Columbia University Irving Medical Center and Weill Cornell Medical College. Women received routine prenatal care and had no major health problems at the time of recruitment. Data were analyzed from January 2018 to March 2020. Exposures: Maternal prepregnancy BMI. Main Outcomes and Measures: The main outcomes were fetal growth, measured as estimated fetal weight, and neonatal functional connectivity, measured using magnetic resonance imaging. Prepregnancy BMI and fetal ultrasonographic measurements were obtained from electronic health record review. Resting-state brain imaging data were acquired in infants within the first month of postnatal life. Functional connectivity was measured using intrinsic functional distribution and seed-based methods. Results: Among 129 women recruited, 105 had ultrasonographic data from at least 2 points and were included in analyses. The mean (SD) age at delivery was 17.82 (1.31) years. Maternal prepregnancy BMI was positively associated with the slope of estimated fetal weight (ß = 0.668; 95% CI, 0.163 to 1.175; P = .01) but not with fetal head circumference (ß = -0.004; 95% CI, -0.024 to 0.016; P = .70). In a subsample of 45 infants with magnetic resonance imaging data, maternal prepregnancy BMI was positively correlated with global connectivity in the left thalamus. Using this thalamic region as a seed, higher maternal BMI was associated with greater local thalamic (both hemispheres) and lower frontothalamic connectivity. Conclusions and Relevance: These results suggest that maternal prepregnancy BMI was associated with the development of regulation of body weight and thalamic functional brain connectivity in offspring even during fetal development.


Assuntos
Encéfalo/crescimento & desenvolvimento , Disfunção Cognitiva/etiologia , Transtornos Mentais/etiologia , Obesidade/complicações , Adolescente , Índice de Massa Corporal , Encéfalo/diagnóstico por imagem , Estudos de Coortes , Feminino , Desenvolvimento Fetal/fisiologia , Humanos , Recém-Nascido , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Gravidez , Cuidado Pré-Natal/normas , Estudos Prospectivos , Habilidades Sociais , Tálamo/diagnóstico por imagem , Tálamo/fisiologia , Adulto Jovem
6.
J Pediatr Urol ; 16(5): 536-542, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32873504

RESUMO

INTRODUCTION: Parasacral transcutaneous electriconeural stimulation (pTENS) is a common treatment modality for patients with overactive bladder (OAB). Its mechanism of effectiveness has yet to be elucidated. Recent studies with fMRI in adults with implanted sacral nerve stimulators impute its effectiveness on changes in the brain involving the anterior cingulate cortex (ACC) and prefrontal cortex (PFC). AIM: The study set out to evaluate brain connectivity utilizing functional MRI to the outline the mechanism of action of pTENS in the brain. METHODS: Ten adult volunteers without urinary tract symptoms underwent fMRI. Electrodes were placed on the skin at sacral level (S2) (Experimental Stimulation - pTENS) and on the right scapular region (Sham Stimulation - sTENS). Stimulation was done twice on each site for 6 min at a frequency of 10 Hz and pulse width of 260 µs and intensity determined by the motor threshold. A 6 min resting state fMRI was also done twice as control. Functional connectivity data was acquired during each state (resting, pTENS and sTENS). Standard functional connectivity preprocessing was performed. Seed connectivity was examined to investigate changes in ACC functional connectivity between the stimulations and resting-state conditions. Significance was assessed at p < 0.05 corrected for multiple comparisons. RESULTS: For all conditions (pTENS, sTENS, and rest), standard patterns of ACC connectivity were detectable with strong connectivity between the ACC and subcortical regions and between the ACC and the frontal lobe. Functional connectivity between ACC seed and the dorsal lateral prefrontal cortex (DLPFC) was significantly increased during pTENS compared to rest. sTENS did not increase connectivity between the ACC seed and DLPFC when compared to rest. DISCUSSION: Preliminary results indicate that ACC is a major site of activation during pTENS. Increased connectivity between ACC and DLPFC may be a possible mechanism of pTENS effectiveness, which appears to be specific to pTENS compared to sTENS. This study is limited to the small size at this time which prevents further investigation at other sites in the brain. CONCLUSIONS: The study confirms our original aim which was to define if parasacral TENS actually has a central effect.


Assuntos
Estimulação Elétrica Nervosa Transcutânea , Bexiga Urinária Hiperativa , Adulto , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Projetos Piloto
7.
Neuroimage ; 212: 116684, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32114151

RESUMO

Real-time functional magnetic resonance imaging (rt-fMRI) neurofeedback is a non-invasive, non-pharmacological therapeutic tool that may be useful for training behavior and alleviating clinical symptoms. Although previous work has used rt-fMRI to target brain activity in or functional connectivity between a small number of brain regions, there is growing evidence that symptoms and behavior emerge from interactions between a number of distinct brain areas. Here, we propose a new method for rt-fMRI, connectome-based neurofeedback, in which intermittent feedback is based on the strength of complex functional networks spanning hundreds of regions and thousands of functional connections. We first demonstrate the technical feasibility of calculating whole-brain functional connectivity in real-time and provide resources for implementing connectome-based neurofeedback. We next show that this approach can be used to provide accurate feedback about the strength of a previously defined connectome-based model of sustained attention, the saCPM, during task performance. Although, in our initial pilot sample, neurofeedback based on saCPM strength did not improve performance on out-of-scanner attention tasks, future work characterizing effects of network target, training duration, and amount of feedback on the efficacy of rt-fMRI can inform experimental or clinical trial designs.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Conectoma/métodos , Neurorretroalimentação/métodos , Neurorretroalimentação/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Projetos Piloto
8.
Biol Psychiatry ; 87(12): 1063-1070, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31668476

RESUMO

BACKGROUND: Activity in the supplementary motor area (SMA) has been associated with tics in Tourette syndrome (TS). The aim of this study was to test a novel intervention-real-time functional magnetic resonance imaging neurofeedback from the SMA-for reduction of tics in adolescents with TS. METHODS: Twenty-one adolescents with TS were enrolled in a double-blind, randomized, sham-controlled, crossover study involving two sessions of neurofeedback from their SMA. The primary outcome measure of tic severity was the Yale Global Tic Severity Scale administered by an independent evaluator before and after each arm. The secondary outcome was control over the SMA assessed in neuroimaging scans, in which subjects were cued to increase/decrease activity in SMA without receiving feedback. RESULTS: All 21 subjects completed both arms of the study and all assessments. Participants had significantly greater reduction of tics on the Yale Global Tic Severity Scale after real neurofeedback as compared with the sham control (p < .05). Mean Yale Global Tic Severity Scale Total Tic score decreased from 25.2 ± 4.6 at baseline to 19.9 ± 5.7 at end point in the neurofeedback condition and from 24.8 ± 8.1 to 23.3 ± 8.5 in the sham control condition. The 3.8-point difference is clinically meaningful and corresponds to an effect size of 0.59. However, there were no differences in changes on the secondary measure of control over the SMA. CONCLUSIONS: This first randomized controlled trial of real-time functional magnetic resonance imaging neurofeedback in adolescents with TS suggests that this neurofeedback intervention may be helpful for improving tic symptoms. However, no effects were found in terms of change in control over the SMA, the hypothesized mechanism of action.


Assuntos
Neurorretroalimentação , Tiques , Síndrome de Tourette , Adolescente , Estudos Cross-Over , Humanos , Imageamento por Ressonância Magnética , Índice de Gravidade de Doença , Tiques/terapia , Síndrome de Tourette/diagnóstico por imagem , Síndrome de Tourette/terapia
9.
Nicotine Tob Res ; 22(3): 324-331, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29917096

RESUMO

INTRODUCTION: Mindfulness training may reduce smoking rates and lessen the association between craving and smoking. This trial tested the efficacy of mindfulness training via smartphone app to reduce smoking. Experience sampling (ES) was used to measure real-time craving, smoking, and mindfulness. METHODS: A researcher-blind, parallel randomized controlled trial compared the efficacy of mobile mindfulness training with experience sampling (MMT-ES; Craving to Quit) versus experience sampling only (ES) to (1) increase 1-week point-prevalence abstinence rates at 6 months, and (2) lessen the association between craving and smoking. A modified intent-to-treat approach was used for treatment starters (MMT-ES n = 143; ES n = 182; 72% female, 81% white, age 41 ± 12 year). RESULTS: No group difference was found in smoking abstinence at 6 months (overall, 11.1%; MMT-ES, 9.8%; ES, 12.1%; χ2(1) = 0.43, p = .51). From baseline to 6 months, both groups showed a reduction in cigarettes per day (p < .0001), craving strength (p < .0001) and frequency (p < .0001), and an increase in mindfulness (p < .05). Using ES data, a craving by group interaction was observed (F(1,3785) = 3.71, p = .05) driven by a stronger positive association between craving and cigarettes per day for ES (t = 4.96, p < .0001) versus MMT-ES (t = 2.03, p = .04). Within MMT-ES, the relationship between craving and cigarettes per day decreased as treatment completion increased (F(1,104) = 4.44, p = .04). CONCLUSIONS: Although mindfulness training via smartphone app did not lead to reduced smoking rates compared with control, our findings provide preliminary evidence that mindfulness training via smartphone app may help lessen the association between craving and smoking, an effect that may be meaningful to support quitting in the longer term. IMPLICATIONS: This is the first reported full-scale randomized controlled trial of any smartphone app for smoking cessation. Findings provide preliminary evidence that smartphone app-based MMT-ES may lessen the association between craving and smoking. TRIAL REGISTRATION: Clinicaltrials.gov NCT02134509.


Assuntos
Fissura , Atenção Plena/métodos , Aplicativos Móveis/estatística & dados numéricos , Smartphone/estatística & dados numéricos , Abandono do Hábito de Fumar/métodos , Fumar/terapia , Adulto , Avaliação Momentânea Ecológica/estatística & dados numéricos , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Fumar/psicologia , Abandono do Hábito de Fumar/psicologia
10.
Front Hum Neurosci ; 12: 496, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30581383

RESUMO

Intentional movement is an internally driven process that requires the integration of motivational and sensory cues with motor preparedness. In addition to the motor cortical-basal ganglia circuits, the limbic circuits are also involved in the integration of these cues. Individuals with Parkinson's disease (PD) have a particular difficulty with internally generating intentional movements and maintaining the speed, size, and vigor of movements. This difficulty improves when they are provided with external cues suggesting that there is a problem with the internal motivation of movement in PD. The prevailing view attributes this difficulty in PD to the dysfunction of motor cortical-basal ganglia circuits. First, we argue that the standard cortical-basal ganglia circuit model of motor dysfunction in PD needs to be expanded to include the insula which is a major hub within the limbic circuits. We propose a neural circuit model highlighting the interaction between the insula and dorsomedial frontal cortex which is involved in generating intentional movements. The insula processes a wide range of sensory signals arising from the body and integrates them with the emotional and motivational context. In doing so, it provides the impetus to the dorsomedial frontal cortex to initiate and sustain movement. Second, we present the results of our proof-of-concept experiment demonstrating that the functional connectivity of the insula-dorsomedial frontal cortex circuit can be enhanced with neurofeedback-guided kinesthetic motor imagery using functional magnetic resonance imaging in subjects with PD. Specifically, we found that the intensity and quality of body sensations evoked during motor imagery and the emotional and motivational context of motor imagery determined the direction (i.e., negative or positive) of the insula-dorsomedial frontal cortex functional connectivity. After 10-12 neurofeedback sessions and "off-line" practice of the successful motor imagery strategies all subjects showed a significant increase in the insula-dorsomedial frontal cortex functional connectivity. Finally, we discuss the implications of these results regarding motor function in patients with PD and propose suggestions for future studies.

11.
Neuroimage ; 181: 807-813, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29729393

RESUMO

Neurofeedback - learning to modulate brain function through real-time monitoring of current brain state - is both a powerful method to perturb and probe brain function and an exciting potential clinical tool. For neurofeedback effects to be useful clinically, they must persist. Here we examine the time course of symptom change following neurofeedback in two clinical populations, combining data from two ongoing neurofeedback studies. This analysis reveals a shared pattern of symptom change, in which symptoms continue to improve for weeks after neurofeedback. This time course has several implications for future neurofeedback studies. Most neurofeedback studies are not designed to test an intervention with this temporal pattern of response. We recommend that new studies incorporate regular follow-up of subjects for weeks or months after the intervention to ensure that the time point of greatest effect is sampled. Furthermore, this time course of continuing clinical change has implications for crossover designs, which may attribute long-term, ongoing effects of real neurofeedback to the control intervention that follows. Finally, interleaving neurofeedback sessions with assessments and examining when clinical improvement peaks may not be an appropriate approach to determine the optimal number of sessions for an application.


Assuntos
Neuroimagem Funcional/métodos , Imageamento por Ressonância Magnética/métodos , Terapias Mente-Corpo/métodos , Neurorretroalimentação/fisiologia , Transtorno Obsessivo-Compulsivo/terapia , Avaliação de Resultados em Cuidados de Saúde , Reconhecimento Visual de Modelos/fisiologia , Córtex Pré-Frontal/fisiopatologia , Síndrome de Tourette/terapia , Adolescente , Adulto , Humanos , Pessoa de Meia-Idade , Córtex Pré-Frontal/diagnóstico por imagem , Fatores de Tempo
12.
Neuroscience ; 378: 11-21, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-27063101

RESUMO

Feedback-driven learning, observed across phylogeny and of clear adaptive value, is frequently operationalized in simple operant conditioning paradigms, but it can be much more complex, driven by abstract representations of success and failure. This study investigates the neural processes involved in processing success and failure during feedback learning, which are not well understood. Data analyzed were acquired during a multisession neurofeedback experiment in which ten participants were presented with, and instructed to modulate, the activity of their orbitofrontal cortex with the aim of decreasing their anxiety. We assessed the regional blood-oxygenation-level-dependent response to the individualized neurofeedback signals of success and failure across twelve functional runs acquired in two different magnetic resonance sessions in each of ten individuals. Neurofeedback signals of failure correlated early during learning with deactivation in the precuneus/posterior cingulate and neurofeedback signals of success correlated later during learning with deactivation in the medial prefrontal/anterior cingulate cortex. The intensity of the latter deactivations predicted the efficacy of the neurofeedback intervention in the reduction of anxiety. These findings indicate a role for regulation of the default mode network during feedback learning, and suggest a higher sensitivity to signals of failure during the early feedback learning and to signals of success subsequently.


Assuntos
Ansiedade/fisiopatologia , Ansiedade/terapia , Encéfalo/fisiopatologia , Aprendizagem/fisiologia , Neurorretroalimentação/fisiologia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Oxigênio/sangue
13.
Drug Alcohol Depend ; 180: 129-136, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28888152

RESUMO

BACKGROUND: Prenatal cocaine exposure (PCE) is linked to addiction and obesity vulnerability. Neural responses to stressful and appetitive cues in adolescents with PCE versus those without have been differentially linked to substance-use initiation. However, no prior studies have assessed cue-reactivity responses among PCE adolescents using a connectivity-based approach. METHODS: Twenty-two PCE and 22 non-prenatally drug-exposed (NDE) age-, sex-, IQ- and BMI-matched adolescents participated in individualized guided imagery with appetitive (favorite-food), stressful and neutral-relaxing cue scripts during functional magnetic resonance imaging. Subjective favorite-food craving scores were collected before and after script exposure. A data-driven voxel-wise intrinsic connectivity distribution analysis was used to identify between-group differences and examine relationships with craving scores. RESULTS: A group-by-cue interaction effect identified a parietal lobe cluster where PCE versus NDE adolescents showed less connectivity during stressful and more connectivity during neutral-relaxing conditions. Follow-up seed-based connectivity analyses revealed that, among PCE adolescents, the parietal seed was positively connected to inferior parietal and sensory areas and negatively connected to corticolimbic during both stress and neutral-relaxing conditions. For NDE, greater parietal connectivity to parietal, cingulate and sensory areas and lesser parietal connectivity to medial prefrontal areas were found during stress compared to neutral-relaxing cueing. Craving scores inversely correlated with corticolimbic connectivity in PCE, but not NDE adolescents, during the favorite-food condition. CONCLUSIONS: Findings from this first data-driven intrinsic connectivity analysis of PCE influences on adolescent brain function indicate differences relating to PCE status and craving. These findings provide insight into the developmental impact of in utero drug exposure.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Cocaína , Imageamento por Ressonância Magnética/métodos , Lobo Parietal/fisiopatologia , Estresse Psicológico/fisiopatologia , Adolescente , Comportamento Aditivo , Transtornos Relacionados ao Uso de Cocaína/epidemiologia , Fissura , Sinais (Psicologia) , Feminino , Alimentos , Humanos , Gravidez , Efeitos Tardios da Exposição Pré-Natal
14.
Nicotine Tob Res ; 18(9): 1820-9, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26995796

RESUMO

INTRODUCTION: Tobacco-use disorder is a complex condition involving multiple brain networks and presenting with multiple behavioral correlates including changes in diet and stress. In a previous functional magnetic resonance imaging (fMRI) study of neural responses to favorite-food, stress, and neutral-relaxing imagery, smokers versus nonsmokers demonstrated blunted corticostriatal-limbic responses to favorite-food cues. Based on other recent reports of alterations in functional brain networks in smokers, the current study examined functional connectivity during exposure to favorite-food, stress, and neutral-relaxing imagery in smokers and nonsmokers, using the same dataset. METHODS: The intrinsic connectivity distribution was measured to identify brain regions that differed in degree of functional connectivity between groups during each imagery condition. Resulting clusters were evaluated for seed-to-voxel connectivity to identify the specific connections that differed between groups during each imagery condition. RESULTS: During exposure to favorite-food imagery, smokers versus nonsmokers showed lower connectivity in the supramarginal gyrus, and differences in connectivity between the supramarginal gyrus and the corticostriatal-limbic system. During exposure to neutral-relaxing imagery, smokers versus nonsmokers showed greater connectivity in the precuneus, and greater connectivity between the precuneus and the posterior insula and rolandic operculum. During exposure to stress imagery, smokers versus nonsmokers showed lower connectivity in the cerebellum. CONCLUSIONS: These findings provide data-driven insights into smoking-related alterations in brain functional connectivity patterns related to appetitive, relaxing, and stressful states. IMPLICATIONS: This study uses a data-driven approach to demonstrate that smokers and nonsmokers show differential patterns of functional connectivity during guided imagery related to personalized favorite-food, stress, and neutral-relaxing cues, in brain regions implicated in attention, reward-related, emotional, and motivational processes. For smokers, these differences in connectivity may impact appetite, stress, and relaxation, and may interfere with smoking cessation.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Alimentos , Relaxamento , Fumar/fisiopatologia , Estresse Psicológico , Tabagismo/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Imagens, Psicoterapia , Imageamento por Ressonância Magnética , Masculino , Abandono do Hábito de Fumar , Prevenção do Hábito de Fumar , Tabagismo/prevenção & controle
15.
Cogn Affect Behav Neurosci ; 15(3): 712-20, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25904238

RESUMO

Meditation has been associated with relatively reduced activity in the default mode network, a brain network implicated in self-related thinking and mind wandering. However, previous imaging studies have typically compared meditation to rest, despite other studies having reported differences in brain activation patterns between meditators and controls at rest. Moreover, rest is associated with a range of brain activation patterns across individuals that has only recently begun to be better characterized. Therefore, in this study we compared meditation to another active cognitive task, both to replicate the findings that meditation is associated with relatively reduced default mode network activity and to extend these findings by testing whether default mode activity was reduced during meditation, beyond the typical reductions observed during effortful tasks. In addition, prior studies had used small groups, whereas in the present study we tested these hypotheses in a larger group. The results indicated that meditation is associated with reduced activations in the default mode network, relative to an active task, for meditators as compared to controls. Regions of the default mode network showing a Group × Task interaction included the posterior cingulate/precuneus and anterior cingulate cortex. These findings replicate and extend prior work indicating that the suppression of default mode processing may represent a central neural process in long-term meditation, and they suggest that meditation leads to relatively reduced default mode processing beyond that observed during another active cognitive task.


Assuntos
Encéfalo/fisiologia , Meditação , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiologia , Testes Neuropsicológicos , Descanso
16.
Brain Behav ; 4(3): 337-47, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24944863

RESUMO

Loving kindness is a form of meditation involving directed well-wishing, typically supported by the silent repetition of phrases such as "may all beings be happy," to foster a feeling of selfless love. Here we used functional magnetic resonance imaging to assess the neural substrate of loving kindness meditation in experienced meditators and novices. We first assessed group differences in blood oxygen level-dependent (BOLD) signal during loving kindness meditation. We next used a relatively novel approach, the intrinsic connectivity distribution of functional connectivity, to identify regions that differ in intrinsic connectivity between groups, and then used a data-driven approach to seed-based connectivity analysis to identify which connections differ between groups. Our findings suggest group differences in brain regions involved in self-related processing and mind wandering, emotional processing, inner speech, and memory. Meditators showed overall reduced BOLD signal and intrinsic connectivity during loving kindness as compared to novices, more specifically in the posterior cingulate cortex/precuneus (PCC/PCu), a finding that is consistent with our prior work and other recent neuroimaging studies of meditation. Furthermore, meditators showed greater functional connectivity during loving kindness between the PCC/PCu and the left inferior frontal gyrus, whereas novices showed greater functional connectivity during loving kindness between the PCC/PCu and other cortical midline regions of the default mode network, the bilateral posterior insula lobe, and the bilateral parahippocampus/hippocampus. These novel findings suggest that loving kindness meditation involves a present-centered, selfless focus for meditators as compared to novices.


Assuntos
Encéfalo/fisiologia , Emoções/fisiologia , Amor , Meditação/psicologia , Rede Nervosa/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Meditação/métodos , Pessoa de Meia-Idade
17.
PLoS One ; 9(3): e93544, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24676034

RESUMO

We present a novel voxel-based connectivity approach for paired functional magnetic resonance imaging (fMRI) data collected under two different conditions labeled the Coupled Intrinsic Connectivity Distribution (coupled-ICD). Our proposed method jointly models both conditions to incorporate additional paired information into the connectivity metric. Voxel-based connectivity holds promise as a clinical tool to characterize a wide range of neurological and psychiatric diseases, and monitor their treatment. As such, examining paired connectivity data such as scans acquired pre- and post-intervention is an important application for connectivity methodologically. When presented with data from paired conditions, conventional voxel-based methods analyze each condition separately. However, summarizing each connection separately can misrepresent patterns of changes in connectivity. We show that commonly used methods can underestimate functional changes and subsequently introduce and evaluate our solution to this problem, the coupled-ICD metric, using two studies: 1) healthy controls scanned awake and under anesthesia, and 2) cocaine-dependent subjects and healthy controls scanned while being presented with relaxing or drug-related imagery cues. The coupled-ICD approach detected differences between paired conditions in similar brain regions as the conventional approaches while also revealing additional changes in regions not identified using conventional voxel-based connectivity analyses. Follow-up seed-based analyses on data independent from the voxel-based results also showed connectivity differences between conditions in regions detected by coupled-ICD. This approach of jointly analyzing paired resting-state scans provides a new and important tool with many applications for clinical and basic neuroscience research.


Assuntos
Mapeamento Encefálico/estatística & dados numéricos , Encéfalo/fisiopatologia , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Processamento de Imagem Assistida por Computador/métodos , Vias Neurais/fisiologia , Algoritmos , Anestesia , Encéfalo/patologia , Mapeamento Encefálico/métodos , Estudos de Casos e Controles , Transtornos Relacionados ao Uso de Cocaína/patologia , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/fisiopatologia , Descanso/psicologia , Vigília/fisiologia
18.
Neuroimage ; 81: 110-118, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23684866

RESUMO

Recent advances in brain imaging have improved the measure of neural processes related to perceptual, cognitive and affective functions, yet the relation between brain activity and subjective experience remains poorly characterized. In part, it is a challenge to obtain reliable accounts of participant's experience in such studies. Here we addressed this limitation by utilizing experienced meditators who are expert in introspection. We tested a novel method to link objective and subjective data, using real-time fMRI (rt-fMRI) to provide participants with feedback of their own brain activity during an ongoing task. We provided real-time feedback during a focused attention task from the posterior cingulate cortex, a hub of the default mode network shown to be activated during mind-wandering and deactivated during meditation. In a first experiment, both meditators and non-meditators reported significant correspondence between the feedback graph and their subjective experience of focused attention and mind-wandering. When instructed to volitionally decrease the feedback graph, meditators, but not non-meditators, showed significant deactivation of the posterior cingulate cortex. We were able to replicate these results in a separate group of meditators using a novel step-wise rt-fMRI discovery protocol in which participants were not provided with prior knowledge of the expected relationship between their experience and the feedback graph (i.e., focused attention versus mind-wandering). These findings support the feasibility of using rt-fMRI to link objective measures of brain activity with reports of ongoing subjective experience in cognitive neuroscience research, and demonstrate the generalization of expertise in introspective awareness to novel contexts.


Assuntos
Atenção/fisiologia , Mapeamento Encefálico/métodos , Giro do Cíngulo/fisiologia , Imageamento por Ressonância Magnética/métodos , Neurorretroalimentação/métodos , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Meditação/psicologia , Pessoa de Meia-Idade , Neurorretroalimentação/fisiologia
19.
J Vis Exp ; (59)2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22297729

RESUMO

We present a method for training subjects to control activity in a region of their orbitofrontal cortex associated with contamination anxiety using biofeedback of real-time functional magnetic resonance imaging (rt-fMRI) data. Increased activity of this region is seen in relationship with contamination anxiety both in control subjects and in individuals with obsessive-compulsive disorder (OCD), a relatively common and often debilitating psychiatric disorder involving contamination anxiety. Although many brain regions have been implicated in OCD, abnormality in the orbitofrontal cortex (OFC) is one of the most consistent findings. Furthermore, hyperactivity in the OFC has been found to correlate with OCD symptom severity and decreases in hyperactivity in this region have been reported to correlate with decreased symptom severity. Therefore, the ability to control this brain area may translate into clinical improvements in obsessive-compulsive symptoms including contamination anxiety. Biofeedback of rt-fMRI data is a new technique in which the temporal pattern of activity in a specific region (or associated with a specific distributed pattern of brain activity) in a subject's brain is provided as a feedback signal to the subject. Recent reports indicate that people are able to develop control over the activity of specific brain areas when provided with rt-fMRI biofeedback. In particular, several studies using this technique to target brain areas involved in emotion processing have reported success in training subjects to control these regions. In several cases, rt-fMRI biofeedback training has been reported to induce cognitive, emotional, or clinical changes in subjects. Here we illustrate this technique as applied to the treatment of contamination anxiety in healthy subjects. This biofeedback intervention will be a valuable basic research tool: it allows researchers to perturb brain function, measure the resulting changes in brain dynamics and relate those to changes in contamination anxiety or other behavioral measures. In addition, the establishment of this method serves as a first step towards the investigation of fMRI-based biofeedback as a therapeutic intervention for OCD. Given that approximately a quarter of patients with OCD receive little benefit from the currently available forms of treatment, and that those who do benefit rarely recover completely, new approaches for treating this population are urgently needed.


Assuntos
Ansiedade/fisiopatologia , Lobo Frontal/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Transtorno Obsessivo-Compulsivo/fisiopatologia , Biorretroalimentação Psicológica/fisiologia , Sistemas Computacionais , Humanos
20.
Brain Connect ; 1(1): 91-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22432958

RESUMO

Recent studies have reported that biofeedback of real-time functional magnetic resonance imaging data can enable people to gain control of activity in specific parts of their brain and can alter functional connectivity between brain areas. Here we describe a study using biofeedback of real-time functional magnetic resonance imaging data to train healthy subjects to control activity in their supplementary motor area (SMA), a region of interest in Tourette syndrome (TS). Although a significant increase in control over the SMA during biofeedback was not found, subjects were able to exert significant control over the SMA in later biofeedback sessions despite not having control in the first biofeedback session. Further, changes were found in their resting state functional connectivity. Specifically, when comparing functional connectivity to the SMA before and after biofeedback, the strength of functional connectivity with subcortical regions was reduced after the biofeedback. This suggests that biofeedback may allow subjects to develop greater conscious control over activity in their SMA by reducing the influence of corticostriatothalamocortical loops on the region. This possibility is promising for TS, where aberrant dynamics in corticostriatothalamocortical loops have long been suspected to give rise to tic symptoms. Further studies in TS patients are needed.


Assuntos
Biorretroalimentação Psicológica/métodos , Biorretroalimentação Psicológica/fisiologia , Sistemas Computacionais , Imageamento por Ressonância Magnética/métodos , Córtex Motor/fisiologia , Rede Nervosa/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiologia , Estimulação Luminosa/métodos , Adulto Jovem
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