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1.
Cogn Behav Ther ; 53(1): 70-86, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37969001

RESUMEN

Exposure and cognitive-based therapies are both effective for PTSD, but knowledge of which intervention is best for which patient is lacking. This lack of knowledge is particularly noticeable for group treatments, as no study has examined whether responses to different group therapies are associated with different pretreatment characteristics. Here, we explored whether pretreatment levels of three types of psychological characteristics-PTSD symptom clusters, posttraumatic cognitions, and emotion regulation difficulties-were associated with symptom reduction during group-delivered cognitive versus exposure-based PTSD treatment. Participants were Veterans with PTSD drawn from two previous clinical trials: one of group CPT (GCPT; n = 32) and the other of group-based exposure therapy (GBET; n = 21). Growth curve modeling was used to identify pretreatment variables that predicted weekly PTSD symptom changes during each therapy. Higher posttraumatic cognitions at pretreatment predicted steeper PTSD symptom reduction during GCPT but not GBET. Additionally, symptom reduction during each therapy was associated with different pretreatment emotion regulation difficulties: difficulties with goal-directed behavior for GBET and lack of emotional clarity and limited access to emotion regulation strategies for GCPT. These findings suggest that assigning Veterans to a group PTSD therapy that better matches their pretreatment psychological profile might facilitate a better therapeutic response.


Asunto(s)
Terapia Cognitivo-Conductual , Terapia Implosiva , Trastornos por Estrés Postraumático , Veteranos , Humanos , Veteranos/psicología , Trastornos por Estrés Postraumático/terapia , Trastornos por Estrés Postraumático/psicología , Resultado del Tratamiento
2.
Proc Natl Acad Sci U S A ; 117(50): 31729-31737, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33257568

RESUMEN

Social influences on decision-making are particularly pronounced during adolescence and have both protective and detrimental effects. To evaluate how responsiveness to social signals may be linked to substance use in adolescents, we used functional neuroimaging and a gambling task in which adolescents who have and have not used substances (substance-exposed and substance-naïve, respectively) made choices alone and after observing peers' decisions. Using quantitative model-based analyses, we identify behavioral and neural evidence that observing others' safe choices increases the subjective value and selection of safe options for substance-naïve relative to substance-exposed adolescents. Moreover, the effects of observing others' risky choices do not vary by substance exposure. These results provide neurobehavioral evidence for a role of positive peers (here, those who make safer choices) in guiding adolescent real-world risky decision-making.


Asunto(s)
Conducta del Adolescente/psicología , Conducta de Elección , Influencia de los Compañeros , Percepción Social/psicología , Trastornos Relacionados con Sustancias/psicología , Adolescente , Femenino , Estilo de Vida Saludable , Humanos , Masculino , Asunción de Riesgos , Trastornos Relacionados con Sustancias/prevención & control
3.
J Clin Psychol ; 78(7): 1376-1387, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35170058

RESUMEN

BACKGROUND: Treatment dropout has been problematic with evidence-based treatments for posttraumatic stress disorder (PTSD), including cognitive processing therapy (CPT). This study sought to evaluate whether CPT group contributed to symptom improvement among treatment completers and non-completers. METHODS: Sixty-one Iraq and Afghanistan combat Veterans self-selected CPT group or treatment as usual (TAU) forming a convenience sample. Defining treatment completion as attending at least nine sessions: 18 completed treatment, 20 dropped-out (DOs); 20 completed TAU, 3 lost to TAU follow-up. RESULTS: Multiple Regression revealed significant pre-post-treatment improvement, the Clinician-Administered PTSD Scale (CAPS-IV, F(5, 40.1) = 2.53, p = 0.0436). Reviewing DOs' last available PTSD Checklist-Military Version scores before leaving treatment, six achieved clinically significant improvement of >10 points; seven a clinically reliable change of 5-10 points. CONCLUSION: These findings highlight that CPT group may be effective at reducing trauma-related symptoms among treatment completers and dropouts and point to the utility of a clinical definition of good treatment end-state.


Asunto(s)
Terapia Cognitivo-Conductual , Personal Militar , Psicoterapia de Grupo , Trastornos por Estrés Postraumático , Veteranos , Humanos , Personal Militar/psicología , Trastornos por Estrés Postraumático/psicología , Resultado del Tratamiento , Veteranos/psicología
4.
Subst Use Misuse ; 53(8): 1299-1310, 2018 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-29308966

RESUMEN

BACKGROUND: Within the dual systems perspective, high reward sensitivity and low punishment sensitivity in conjunction with deficits in cognitive control may contribute to high levels of risk taking, such as substance use. OBJECTIVE: The current study examined whether the individual components of effortful control (inhibitory control, attentional control, and activation control) serve as regulators and moderate the association between reward or punishment sensitivity and substance use behaviors. METHOD: A total of 1,808 emerging adults from a university setting (Mean age = 19.48; 72% female) completed self-report measures of reward and punishment sensitivity, effortful control, and substance use. RESULTS: Findings indicated significant two-way interactions for punishment sensitivity and inhibitory control for alcohol and marijuana use. The form of these interactions revealed a significant negative association between punishment sensitivity and alcohol and marijuana use at low levels of inhibitory control. No significant interactions emerged for reward sensitivity or other components of effortful control. CONCLUSIONS: The current findings provide preliminary evidence suggesting the dual systems theorized to influence risk taking behavior interact to make joint contributions to health risk behaviors such as substance use in emerging adults.


Asunto(s)
Consumo de Bebidas Alcohólicas/psicología , Control Interno-Externo , Uso de la Marihuana/psicología , Castigo/psicología , Recompensa , Temperamento , Adolescente , Adulto , Femenino , Humanos , Masculino , Autoimagen , Adulto Joven
5.
J Res Adolesc ; 27(3): 674-682, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28776832

RESUMEN

The developmental period of adolescence is characterized by increasing incidence of health risk behaviors (HRBs). Based on theoretical models that emphasize the moderating role of cognitive control, this study examined how neural correlates of cognitive control and risk sensitivity interact to predict HRBs among late adolescents (17-20 years). Neuroimaging data indicate that risk-related hemodynamic activity in the anterior insula during anticipation of uncertain outcomes predicts HRBs among late adolescents exhibiting greater dorsal anterior cingulate cortex (dACC) activity during a cognitive interference task but not among late adolescents requiring less dACC activity. These results present neural evidence for a significant moderating effect of cognitive control on the link between risk sensitivity and HRBs among late adolescents.


Asunto(s)
Desarrollo del Adolescente/fisiología , Cognición/fisiología , Conductas de Riesgo para la Salud , Adolescente , Adulto , Encéfalo/diagnóstico por imagen , Toma de Decisiones , Femenino , Humanos , Masculino , Factores de Riesgo , Conducta Sexual/estadística & datos numéricos , Adulto Joven
6.
Cogn Affect Behav Neurosci ; 15(2): 276-86, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25348668

RESUMEN

The duration and quality of human performance depend on both intrinsic motivation and external incentives. However, little is known about the neuroscientific basis of this interplay between internal and external motivators. Here, we used functional magnetic resonance imaging to examine the neural substrates of intrinsic motivation, operationalized as the free-choice time spent on a task when this was not required, and tested the neural and behavioral effects of external reward on intrinsic motivation. We found that increased duration of free-choice time was predicted by generally diminished neural responses in regions associated with cognitive and affective regulation. By comparison, the possibility of additional reward improved task accuracy, and specifically increased neural and behavioral responses following errors. Those individuals with the smallest neural responses associated with intrinsic motivation exhibited the greatest error-related neural enhancement under the external contingency of possible reward. Together, these data suggest that human performance is guided by a "tonic" and "phasic" relationship between the neural substrates of intrinsic motivation (tonic) and the impact of external incentives (phasic).


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiología , Motivación , Recompensa , Encéfalo/irrigación sanguínea , Conducta de Elección , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Lineales , Imagen por Resonancia Magnética , Masculino , Oxígeno/sangre , Valor Predictivo de las Pruebas , Análisis de Componente Principal , Solución de Problemas , Tiempo de Reacción
7.
Curr Biol ; 33(22): 5003-5010.e6, 2023 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-37875110

RESUMEN

The noradrenaline (NA) system is one of the brain's major neuromodulatory systems; it originates in a small midbrain nucleus, the locus coeruleus (LC), and projects widely throughout the brain.1,2 The LC-NA system is believed to regulate arousal and attention3,4 and is a pharmacological target in multiple clinical conditions.5,6,7 Yet our understanding of its role in health and disease has been impeded by a lack of direct recordings in humans. Here, we address this problem by showing that electrochemical estimates of sub-second NA dynamics can be obtained using clinical depth electrodes implanted for epilepsy monitoring. We made these recordings in the amygdala, an evolutionarily ancient structure that supports emotional processing8,9 and receives dense LC-NA projections,10 while patients (n = 3) performed a visual affective oddball task. The task was designed to induce different cognitive states, with the oddball stimuli involving emotionally evocative images,11 which varied in terms of arousal (low versus high) and valence (negative versus positive). Consistent with theory, the NA estimates tracked the emotional modulation of attention, with a stronger oddball response in a high-arousal state. Parallel estimates of pupil dilation, a common behavioral proxy for LC-NA activity,12 supported a hypothesis that pupil-NA coupling changes with cognitive state,13,14 with the pupil and NA estimates being positively correlated for oddball stimuli in a high-arousal but not a low-arousal state. Our study provides proof of concept that neuromodulator monitoring is now possible using depth electrodes in standard clinical use.


Asunto(s)
Atención , Norepinefrina , Humanos , Atención/fisiología , Nivel de Alerta/fisiología , Amígdala del Cerebelo , Encéfalo , Locus Coeruleus/fisiología , Pupila/fisiología
8.
Neuron ; 57(3): 463-73, 2008 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-18255038

RESUMEN

Attributing behavioral outcomes correctly to oneself or to other agents is essential for all productive social exchange. We approach this issue in high-functioning males with autism spectrum disorder (ASD) using two separate fMRI paradigms. First, using a visual imagery task, we extract a basis set for responses along the cingulate cortex of control subjects that reveals an agent-specific eigenvector (self eigenmode) associated with imagining oneself executing a specific motor act. Second, we show that the same self eigenmode arises during one's own decision (the self phase) in an interpersonal exchange game (iterated trust game). Third, using this exchange game, we show that ASD males exhibit a severely diminished cingulate self response when playing the game with a human partner. This diminishment covaries parametrically with their behaviorally assessed symptom severity, suggesting its value as an objective endophenotype. These findings may provide a quantitative assessment tool for high-functioning ASD.


Asunto(s)
Trastorno Autístico , Giro del Cíngulo/fisiopatología , Conducta Imitativa/fisiología , Procesos Mentales/fisiología , Fenotipo , Autoimagen , Adolescente , Adulto , Trastorno Autístico/patología , Trastorno Autístico/fisiopatología , Trastorno Autístico/psicología , Mapeo Encefálico , Estudios de Casos y Controles , Giro del Cíngulo/irrigación sanguínea , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Pruebas Neuropsicológicas , Oxígeno/sangre , Estimulación Luminosa/métodos , Análisis de Componente Principal
9.
Nat Neurosci ; 11(4): 514-20, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18311134

RESUMEN

Addicted individuals pursue substances of abuse even in the clear presence of positive outcomes that may be foregone and negative outcomes that may occur. Computational models of addiction depict the addicted state as a feature of a valuation disease, where drug-induced reward prediction error signals steer decisions toward continued drug use. Related models admit the possibility that valuation and choice are also directed by 'fictive' outcomes (outcomes that have not been experienced) that possess their own detectable error signals. We hypothesize that, in addiction, anomalies in these fictive error signals contribute to the diminished influence of potential consequences. Using a simple investment game and functional magnetic resonance imaging in chronic cigarette smokers, we measured neural and behavioral responses to error signals derived from actual experience and from fictive outcomes. In nonsmokers, both fictive and experiential error signals predicted subjects' choices and possessed distinct neural correlates. In chronic smokers, choices were not guided by error signals derived from what might have happened, despite ongoing and robust neural correlates of these fictive errors. These data provide human neuroimaging support for computational models of addiction and suggest the addition of fictive learning signals to reinforcement learning accounts of drug dependence.


Asunto(s)
Atención/fisiología , Conducta Adictiva/psicología , Área de Dependencia-Independencia , Inhibición Psicológica , Fumar/psicología , Tabaquismo/psicología , Adulto , Mapeo Encefálico , Corteza Cerebral/fisiología , Conducta de Elección , Femenino , Juegos Experimentales , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Modelos Psicológicos , Aprendizaje Seriado/fisiología
10.
J Trauma Stress ; 24(5): 538-45, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21882249

RESUMEN

The events of September 11, 2001 created unprecedented uncertainty about safety in the United States and created an aftermath with significant psychological impact across the world. This study examined emotional information encoding in 31 healthy individuals whose stress response symptoms ranged from none to a moderate level shortly after the attacks as assessed by the Impact of Event Scale-Revised. Participants viewed attack-related, negative (but attack-irrelevant), and neutral images while their event-related brain potentials (ERPs) were recorded. Attack images elicited enhanced P300 relative to negative and neutral images, and emotional images prompted larger slow waves than neutral images did. Total symptoms were correlated with altered N2, P300, and slow wave responses during valence processing. Specifically, hyperarousal and intrusion symptoms were associated with diminished stimulus discrimination between neutral and unpleasant images; avoidance symptoms were associated with hypervigilance, as suggested by reduced P300 difference between attack and other images and reduced appraisal of attack images as indicated by attenuated slow wave. The findings in this minimally symptomatic sample are compatible with the alterations in cognition in the posttraumatic stress disorder (PTSD) literature and are consistent with a dimensional model of PTSD.


Asunto(s)
Potenciales Evocados Visuales/fisiología , Ataques Terroristas del 11 de Septiembre/psicología , Boston , Femenino , Humanos , Masculino , Fotograbar , Trastornos por Estrés Postraumático/fisiopatología
11.
JAMA Psychiatry ; 78(10): 1113-1122, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34319349

RESUMEN

Importance: Major depressive disorder is prevalent and impairing. Parsing neurocomputational substrates of reinforcement learning in individuals with depression may facilitate a mechanistic understanding of the disorder and suggest new cognitive therapeutic targets. Objective: To determine associations among computational model-derived reinforcement learning parameters, depression symptoms, and symptom changes after treatment. Design, Setting, and Participants: In this mixed cross-sectional-cohort study, individuals performed reward and loss variants of a probabilistic learning task during functional magnetic resonance imaging at baseline and follow-up. A volunteer sample with and without a depression diagnosis was recruited from the community. Participants were assessed from July 2011 to February 2017, and data were analyzed from May 2017 to May 2021. Main Outcomes and Measures: Computational model-based analyses of participants' choices assessed a priori hypotheses about associations between components of reward-based and loss-based learning with depression symptoms. Changes in both learning parameters and symptoms were then assessed in a subset of participants who received cognitive behavioral therapy (CBT). Results: Of 101 included adults, 69 (68.3%) were female, and the mean (SD) age was 34.4 (11.2) years. A total of 69 participants with a depression diagnosis and 32 participants without a depression diagnosis were included at baseline; 48 participants (28 with depression who received CBT and 20 without depression) were included at follow-up (mean [SD] of 115.1 [15.6] days). Computational model-based analyses of behavioral choices and neural data identified associations of learning with symptoms during reward learning and loss learning, respectively. During reward learning only, anhedonia (and not negative affect or arousal) was associated with model-derived learning parameters (learning rate: posterior mean regression ß = -0.14; 95% credible interval [CrI], -0.12 to -0.03; outcome sensitivity: posterior mean regression ß = 0.18; 95% CrI, 0.02 to 0.37) and neural learning signals (moderation of association between striatal prediction error and expected value signals: t97 = -2.10; P = .04). During loss learning only, negative affect (and not anhedonia or arousal) was associated with learning parameters (outcome shift: posterior mean regression ß = -0.11; 95% CrI, -0.20 to -0.01) and disrupted neural encoding of learning signals (association with subgenual anterior cingulate prediction error signals: r = -0.28; P = .005). Symptom improvement following CBT was associated with normalization of learning parameters that were disrupted at baseline (reward learning rate: posterior mean regression ß = 0.15; 90% CrI, 0.001 to 0.41; loss outcome shift: posterior mean regression ß = 0.42; 90% CrI, 0.09 to 0.77). Conclusions and Relevance: In this study, the mapping of reinforcement learning components to symptoms of major depression revealed mechanistic features associated with these symptoms and points to possible learning-based therapeutic processes and targets.


Asunto(s)
Terapia Cognitivo-Conductual , Trastorno Depresivo Mayor/fisiopatología , Trastorno Depresivo Mayor/terapia , Giro del Cíngulo/fisiopatología , Refuerzo en Psicología , Estriado Ventral/fisiopatología , Adulto , Mapeo Encefálico , Estudios Transversales , Trastorno Depresivo Mayor/diagnóstico por imagen , Femenino , Giro del Cíngulo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Aprendizaje por Probabilidad , Recompensa , Estriado Ventral/diagnóstico por imagen , Adulto Joven
12.
Artículo en Inglés | MEDLINE | ID: mdl-31759868

RESUMEN

BACKGROUND: Aberrant emotion processing is a hallmark of posttraumatic stress disorder (PTSD), with neurobiological models suggesting both heightened neural reactivity and diminished habituation to aversive stimuli. However, empirical work suggests that these response patterns may be specific to subsets of those with PTSD. This study investigates the unique contributions of PTSD symptom clusters (re-experiencing, avoidance and numbing, and hyperarousal) to neural reactivity and habituation to negative stimuli in combat-exposed veterans. METHODS: Ninety-five combat-exposed veterans (46 with PTSD) and 53 community volunteers underwent functional magnetic resonance imaging while viewing emotional images. This study examined the relationship between symptom cluster severity and hemodynamic responses to negative compared with neutral images (NEG>NEU). RESULTS: Veterans exhibited comparable mean and habituation-related responses for NEG>NEU, relative to civilians. However, among veterans, habituation, but not mean response, was differentially related to PTSD symptom severity. Hyperarousal symptoms were related to decreased habituation for NEG>NEU in a network of regions, including superior and inferior frontal gyri, ventromedial prefrontal cortex, superior and middle temporal gyri, and anterior insula. In contrast, re-experiencing symptoms were associated with increased habituation in a similar network. Furthermore, re-experiencing severity was positively related to amygdalar functional connectivity with the left inferior frontal gyrus and dorsal anterior cingulate cortex for NEG>NEU. CONCLUSIONS: These results indicate that hyperarousal symptoms in combat-related PTSD are associated with decreased neural habituation to aversive stimuli. These impairments are partially mitigated in the presence of re-experiencing symptoms, such that during exposure to negative stimuli, re-experiencing symptoms are positively associated with amygdalar connectivity to prefrontal regions implicated in affective suppression.


Asunto(s)
Habituación Psicofisiológica , Trastornos por Estrés Postraumático , Veteranos , Adulto , Amígdala del Cerebelo , Nivel de Alerta , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Trastornos por Estrés Postraumático/fisiopatología , Estados Unidos , Adulto Joven
13.
Artículo en Inglés | MEDLINE | ID: mdl-30297162

RESUMEN

BACKGROUND: In substance-dependent individuals, drug deprivation and drug use trigger divergent behavioral responses to environmental cues. These divergent responses are consonant with data showing that short- and long-term adaptations in dopamine signaling are similarly sensitive to state of drug use. The literature suggests a drug state-dependent role of learning in maintaining substance use; evidence linking dopamine to both reinforcement learning and addiction provides a framework to test this possibility. METHODS: In a randomized crossover design, 22 participants with current cocaine use disorder completed a probabilistic loss-learning task during functional magnetic resonance imaging while on and off cocaine (44 sessions). Another 54 participants without Axis I psychopathology served as a secondary reference group. Within-drug state and paired-subjects' learning effects were assessed with computational model-derived individual learning parameters. Model-based neuroimaging analyses evaluated effects of drug use state on neural learning signals. Relationships among model-derived behavioral learning rates (α+, α-), neural prediction error signals (δ+, δ-), cocaine use, and desire to use were assessed. RESULTS: During cocaine deprivation, cocaine-dependent individuals exhibited heightened positive learning rates (α+), heightened neural positive prediction error (δ+) responses, and heightened association of α+ with neural δ+ responses. The deprivation-enhanced neural learning signals were specific to successful loss avoidance, comparable to participants without psychiatric conditions, and mediated a relationship between chronicity of drug use and desire to use cocaine. CONCLUSIONS: Neurocomputational learning signals are sensitive to drug use status and suggest that heightened reinforcement by successful avoidance of negative outcomes may contribute to drug seeking during deprivation. More generally, attention to drug use state is important for delineating substrates of addiction.


Asunto(s)
Reacción de Prevención , Encéfalo/fisiopatología , Trastornos Relacionados con Cocaína/fisiopatología , Trastornos Relacionados con Cocaína/psicología , Aprendizaje/fisiología , Adulto , Mapeo Encefálico , Estudios Cruzados , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Modelos Psicológicos , Refuerzo en Psicología
14.
Neuroimage ; 42(2): 988-97, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18556218

RESUMEN

The integrity of decision-making under emotionally evocative circumstances is critical to navigating complex environments, and dysfunctions in these processes may play an important role in the emergence and maintenance of various psychopathologies. The goal of the present study was to examine the spatial and temporal dynamics of neural responses to emotional stimuli and emotion-modulated response inhibition. High-density event-related brain potentials (ERPs) were measured as participants (N=25) performed an emotional Go/NoGo task that required button presses to words of a "target" emotional valence (i.e., positive, negative, neutral) and response inhibition to words of a different "distractor" valence. Using scalp ERP analyses in conjunction with source-localization techniques, we identified distinct neural responses associated with affective salience and affect-modulated response inhibition, respectively. Both earlier (approximately 300 ms) and later (approximately 700 ms) ERP components were enhanced with successful response inhibition to emotional distractors. Only ERPs to target stimuli differentiated affective from neutral cues. Moreover, source localization analyses revealed right ventral lateral prefrontal cortex (VLPFC) activation in affective response inhibition regardless of emotional valence, whereas rostral anterior cingulate activation (rACC) was potentiated by emotional valence but was not modulated by response inhibition. This dissociation was supported by a significant Region x Trial Type x Emotion interaction, confirming that distinct regional dynamics characterize neural responses to affective valence and affective response-inhibition. The results are discussed in the context of an emerging affective neuroscience literature and implications for understanding psychiatric pathologies characterized by a detrimental susceptibility to emotional cues, with an emphasis on major depressive disorder.


Asunto(s)
Toma de Decisiones/fisiología , Emociones/fisiología , Lóbulo Frontal/fisiología , Giro del Cíngulo/fisiología , Inhibición Psicológica , Plasticidad Neuronal/fisiología , Femenino , Humanos , Masculino , Análisis y Desempeño de Tareas , Adulto Joven
15.
Elife ; 72018 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-29313489

RESUMEN

Disproportionate reactions to unexpected stimuli in the environment are a cardinal symptom of posttraumatic stress disorder (PTSD). Here, we test whether these heightened responses are associated with disruptions in distinct components of reinforcement learning. Specifically, using functional neuroimaging, a loss-learning task, and a computational model-based approach, we assessed the mechanistic hypothesis that overreactions to stimuli in PTSD arise from anomalous gating of attention during learning (i.e., associability). Behavioral choices of combat-deployed veterans with and without PTSD were fit to a reinforcement learning model, generating trial-by-trial prediction errors (signaling unexpected outcomes) and associability values (signaling attention allocation to the unexpected outcomes). Neural substrates of associability value and behavioral parameter estimates of associability updating, but not prediction error, increased with PTSD during loss learning. Moreover, the interaction of PTSD severity with neural markers of associability value predicted behavioral choices. These results indicate that increased attention-based learning may underlie aspects of PTSD and suggest potential neuromechanistic treatment targets.


Asunto(s)
Aprendizaje , Trastornos Mentales/fisiopatología , Trastornos por Estrés Postraumático/fisiopatología , Adulto , Simulación por Computador , Neuroimagen Funcional , Humanos , Persona de Mediana Edad , Refuerzo en Psicología , Veteranos , Adulto Joven
16.
Am J Psychiatry ; 164(4): 608-16, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17403974

RESUMEN

OBJECTIVE: Anomalies in error processing have been implicated in the etiology and maintenance of major depressive disorder. In particular, depressed individuals exhibit heightened sensitivity to error-related information and negative environmental cues, along with reduced responsivity to positive reinforcers. The authors examined the neural activation associated with error processing in individuals diagnosed with and without major depression and the sensitivity of these processes to modulation by monetary task contingencies. METHOD: The error-related negativity and error-related positivity components of the event-related potential were used to characterize error monitoring in individuals with major depressive disorder and the degree to which these processes are sensitive to modulation by monetary reinforcement. Nondepressed comparison subjects (N=17) and depressed individuals (N=18) performed a flanker task under two external motivation conditions (i.e., monetary reward for correct responses and monetary loss for incorrect responses) and a nonmonetary condition. After each response, accuracy feedback was provided. The error-related negativity component assessed the degree of anomaly in initial error detection, and the error positivity component indexed recognition of errors. RESULTS: Across all conditions, the depressed participants exhibited greater amplitude of the error-related negativity component, relative to the comparison subjects, and equivalent error positivity amplitude. In addition, the two groups showed differential modulation by task incentives in both components. CONCLUSIONS: These data implicate exaggerated early error-detection processes in the etiology and maintenance of major depressive disorder. Such processes may then recruit excessive neural and cognitive resources that manifest as symptoms of depression.


Asunto(s)
Conducta de Elección/fisiología , Trastorno Depresivo Mayor/diagnóstico , Potenciales Evocados/fisiología , Desempeño Psicomotor/fisiología , Recompensa , Adulto , Señales (Psicología) , Trastorno Depresivo Mayor/etiología , Trastorno Depresivo Mayor/fisiopatología , Retroalimentación/fisiología , Femenino , Giro del Cíngulo/fisiopatología , Humanos , Masculino , Motivación , Análisis y Desempeño de Tareas , Régimen de Recompensa
17.
Sci Rep ; 7: 44374, 2017 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-28281665

RESUMEN

The clinical diagnosis and symptoms of major depressive disorder (MDD) have been closely associated with impairments in reward processing. In particular, various studies have shown blunted neural and behavioral responses to the experience of reward in depression. However, little is known about whether depression affects individuals' valuation of potential rewards during decision-making, independent from reward experience. To address this question, we used a gambling task and a model-based analytic approach to measure two types of individual sensitivity to reward values in participants with MDD: 'risk preference,' indicating how objective values are subjectively perceived, and 'inverse temperature,' determining the degree to which subjective value differences between options influence participants' choices. On both of these measures of value sensitivity, participants with MDD were comparable to non-psychiatric controls. In addition, both risk preference and inverse temperature were stable over four laboratory visits and comparable between the groups at each visit. Neither valuation measure varied with severity of clinical symptoms in MDD. These data suggest intact and stable value processing in MDD during risky decision-making.


Asunto(s)
Conducta de Elección/fisiología , Toma de Decisiones/fisiología , Trastorno Depresivo Mayor/psicología , Juego de Azar/psicología , Asunción de Riesgos , Adulto , Anhedonia/fisiología , Estudios de Casos y Controles , Trastorno Depresivo Mayor/fisiopatología , Femenino , Juegos Experimentales , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Recompensa
18.
Neuropsychologia ; 100: 79-92, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28416327

RESUMEN

The current review is guided by the theoretical perspective that emphasizes the regulating role of executive functioning (Carver et al., 2009) and presents studies that elucidate the ways that executive functioning (inhibition and working memory) explain individual differences in adolescent substance use independently or by regulating the reactive system (reward and punishment sensitivity). Behavioral studies indicate that main effects of executive functioning on adolescent substance use are often nonsignificant or weak in effect sizes. In contrast, emerging evidence suggests consistent and stronger regulating effects of executive functioning over reward and punishment sensitivity. Functional neuroimaging studies reveal significant associations between executive functioning task-related hemodynamic responses and substance use with strong effect sizes. There is also direct evidence from studies testing statistical interactions of the regulating effects of EF-related brain activation, and indirect evidence in studies examining functional connectivity, temporal discounting, and reinforced control. We note key future directions and ways to address limitations in existing work.


Asunto(s)
Trastornos del Conocimiento/etiología , Función Ejecutiva/fisiología , Trastornos Relacionados con Sustancias/fisiopatología , Adolescente , Trastornos del Conocimiento/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Trastornos Relacionados con Sustancias/diagnóstico por imagen , Trastornos Relacionados con Sustancias/psicología
20.
Int J Behav Dev ; 40(1): 58-63, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26770006

RESUMEN

Adolescence is characterized by increasing incidence of health risk behaviors, including experimentation with drugs and alcohol. To fill the gap in our understanding of the associations between risky decision-making and health risk behaviors, we investigated associations between laboratory-based risky decision-making using the Stoplight task and self-reported health risk behaviors. Given that there has been no examination of potential age differences in the associations between risky decision-making and health risk behaviors, we also examined whether the association of risky decision-making with health risk behaviors is consistent across adolescence and adulthood using two-group structural equation modeling (SEM). The results indicated significant differences across the two age groups: adolescents (17-20 year olds) who took more risks on the Stoplight task reported greater frequency and earlier onset of substance use, whereas stoplight performance was not associated with substance use frequency or onset among adults (31-61 year olds). Our findings suggest that a laboratory-based measure of risky decision-making is significantly related to health risk behaviors among adolescents but not among adults.

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