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1.
J Exp Psychol Gen ; 153(6): 1582-1604, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38884963

RESUMEN

Agency is the sense that one has control over one's own actions and the consequences of those actions. Despite the critical role that agency plays in the human condition, little is known about its neural basis. A novel theory proposes that increases in agency disinhibit the dopamine system and thereby increase the number of tonically active dopamine neurons in the ventral tegmental area. The theory, called ADDS (Agency Disinhibits the Dopamine System), proposes a specific neural network that mediates these effects. ADDS accurately predicts a variety of relevant neuroscience results, and makes many novel predictions, including that increases in an agency will (a) increase motivation, (b) improve executive function, (c) facilitate procedural learning, but only in the presence of immediate trial-by-trial feedback, (d) have little or no effect on learning-related effects of stimulus repetition or on standard eyeblink conditioning, (e) facilitate the development of automatic behaviors, but have little or no effect on the production of behaviors that are already automatized, (f) amplify the cognitive benefits of positive mood, and (g) reduce pain. The implications of this new theory are considered for several purely psychological theories that assign prominent roles to agency, including self-efficacy theory, hope theory, and goal-focused positive psychotherapy. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Asunto(s)
Afecto , Cognición , Dopamina , Teoría Psicológica , Humanos , Afecto/fisiología , Dopamina/metabolismo , Dopamina/fisiología , Cognición/fisiología , Motivación/fisiología , Función Ejecutiva/fisiología
2.
Psychophysiology ; 60(5): e14235, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36529988

RESUMEN

While frontal midline theta (FMθ) has been associated with threat processing, with cognitive control in the context of anxiety, and with reinforcement learning, most reinforcement learning studies on FMθ have used reward rather than threat-related stimuli as reinforcer. Accordingly, the role of FMθ in threat-related reinforcement learning is largely unknown. Here, n = 23 human participants underwent one reward-, and one punishment-, based reversal learning task, which differed only with regard to the kind of reinforcers that feedback was tied to (i.e., monetary gain vs. loud noise burst, respectively). In addition to single-trial EEG, we assessed single-trial feedback expectations based on both a reinforcement learning computational model and trial-by-trial subjective feedback expectation ratings. While participants' performance and feedback expectations were comparable between the reward and punishment tasks, FMθ was more reliably amplified to negative vs. positive feedback in the reward vs. punishment task. Regressions with feedback valence, computationally derived, and self-reported expectations as predictors and FMθ as criterion further revealed that trial-by-trial variations in FMθ specifically relate to reward-related feedback-valence and not to threat-related feedback or to violated expectations/prediction errors. These findings suggest that FMθ as measured in reinforcement learning tasks may be less sensitive to the processing of events with direct relevance for fear and anxiety.


Asunto(s)
Reacción de Prevención , Recompensa , Humanos , Retroalimentación , Refuerzo en Psicología , Castigo , Electroencefalografía
3.
Biol Psychol ; 146: 107735, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31352030

RESUMEN

Trait extraversion has been theorized to emerge from functioning of the dopaminergic reward system. Recent evidence for this view shows that extraversion modulates the scalp-recorded Reward Positivity, a putative marker of dopaminergic signaling of reward-prediction-error. We attempt to replicate this association amid several improvements on previous studies in this area, including an adequately-powered sample (N = 100) and thorough examination of convergent-divergent validity. Participants completed a passive associative learning task presenting rewards and non-rewards that were either predictable or unexpected. Frequentist and Bayesian analyses confirmed that the scalp recorded Reward Positivity (i.e., the Feedback-Related-Negativity contrasting unpredicted rewards and unpredicted non-rewards) was significantly associated with three measures of extraversion and unrelated to other basic traits from the Big Five personality model. Narrower sub-traits of extraversion showed similar, though weaker associations with the Reward Positivity. These findings consolidate previous evidence linking extraversion with a putative marker of dopaminergic reward-processing.


Asunto(s)
Electroencefalografía , Extraversión Psicológica , Recompensa , Adolescente , Adulto , Anticipación Psicológica , Aprendizaje por Asociación , Dopamina/fisiología , Retroalimentación Psicológica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Personalidad , Desempeño Psicomotor/fisiología , Adulto Joven
4.
Cogn Emot ; 33(4): 832-839, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-29781382

RESUMEN

People high in social anxiety experience fear of social situations due to the likelihood of social evaluation. Whereas happy faces are generally processed very quickly, this effect is impaired by high social anxiety. Mouth regions are implicated during emotional face processing, therefore differences in mouth salience might affect how social anxiety relates to emotional face discrimination. We designed an emotional facial expression recognition task to reveal how varying levels of sub-clinical social anxiety (measured by questionnaire) related to the discrimination of happy and fearful faces, and of happy and angry faces. We also categorised the facial expressions by the salience of the mouth region (i.e. high [open mouth] vs. low [closed mouth]). In a sample of 90 participants higher social anxiety (relative to lower social anxiety) was associated with a reduced happy face reaction time advantage. However, this effect was mainly driven by the faces with less salient closed mouths. Our results are consistent with theories of anxiety that incorporate an oversensitive valence evaluation system.


Asunto(s)
Ansiedad/psicología , Discriminación en Psicología/fisiología , Emociones/fisiología , Expresión Facial , Reconocimiento Facial/fisiología , Boca , Adulto , Femenino , Humanos , Londres , Masculino , Adulto Joven
6.
Front Hum Neurosci ; 8: 740, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25324752

RESUMEN

Phasic firing changes of midbrain dopamine neurons have been widely characterized as reflecting a reward prediction error (RPE). Major personality traits (e.g., extraversion) have been linked to inter-individual variations in dopaminergic neurotransmission. Consistent with these two claims, recent research (Smillie et al., 2011; Cooper et al., 2014) found that extraverts exhibited larger RPEs than introverts, as reflected in feedback related negativity (FRN) effects in EEG recordings. Using an established, biologically-localized RPE computational model, we successfully simulated dopaminergic cell firing changes which are thought to modulate the FRN. We introduced simulated individual differences into the model: parameters were systematically varied, with stable values for each simulated individual. We explored whether a model parameter might be responsible for the observed covariance between extraversion and the FRN changes in real data, and argued that a parameter is a plausible source of such covariance if parameter variance, across simulated individuals, correlated almost perfectly with the size of the simulated dopaminergic FRN modulation, and created as much variance as possible in this simulated output. Several model parameters met these criteria, while others did not. In particular, variations in the strength of connections carrying excitatory reward drive inputs to midbrain dopaminergic cells were considered plausible candidates, along with variations in a parameter which scales the effects of dopamine cell firing bursts on synaptic modification in ventral striatum. We suggest possible neurotransmitter mechanisms underpinning these model parameters. Finally, the limitations and possible extensions of our general approach are discussed.

7.
Front Hum Neurosci ; 8: 248, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24808845

RESUMEN

Medial-frontal negativity occurring ∼200-300 ms post-stimulus in response to motivationally salient stimuli, usually referred to as feedback-related negativity (FRN), appears to be at least partly modulated by dopaminergic-based reward prediction error (RPE) signaling. Previous research (e.g., Smillie et al., 2011) has shown that higher scores on a putatively dopaminergic-based personality trait, extraversion, were associated with a more pronounced difference wave contrasting unpredicted non-reward and unpredicted reward trials on an associative learning task. In the current study, we sought to extend this research by comparing how trait measures of reward sensitivity, impulsivity and extraversion related to the FRN using the same associative learning task. A sample of healthy adults (N = 38) completed a battery of personality questionnaires, before completing the associative learning task while EEG was recorded. As expected, FRN was most negative following unpredicted non-reward. A difference wave contrasting unpredicted non-reward and unpredicted reward trials was calculated. Extraversion, but not measures of impulsivity, had a significant association with this difference wave. Further, the difference wave was significantly related to a measure of anticipatory pleasure, but not consummatory pleasure. These findings provide support for the existing evidence suggesting that variation in dopaminergic functioning in brain "reward" pathways may partially underpin associations between the FRN and trait measures of extraversion and anticipatory pleasure.

8.
Front Psychol ; 4: 279, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23734136

RESUMEN

The psychology of conspiracy theory beliefs is not yet well understood, although research indicates that there are stable individual differences in conspiracist ideation - individuals' general tendency to engage with conspiracy theories. Researchers have created several short self-report measures of conspiracist ideation. These measures largely consist of items referring to an assortment of prominent conspiracy theories regarding specific real-world events. However, these instruments have not been psychometrically validated, and this assessment approach suffers from practical and theoretical limitations. Therefore, we present the Generic Conspiracist Beliefs (GCB) scale: a novel measure of individual differences in generic conspiracist ideation. The scale was developed and validated across four studies. In Study 1, exploratory factor analysis of a novel 75-item measure of non-event-based conspiracist beliefs identified five conspiracist facets. The 15-item GCB scale was developed to sample from each of these themes. Studies 2, 3, and 4 examined the structure and validity of the GCB, demonstrating internal reliability, content, criterion-related, convergent and discriminant validity, and good test-retest reliability. In sum, this research indicates that the GCB is a psychometrically sound and practically useful measure of conspiracist ideation, and the findings add to our theoretical understanding of conspiracist ideation as a monological belief system unpinned by a relatively small number of generic assumptions about the typicality of conspiratorial activity in the world.

9.
Psychiatry Res ; 196(2-3): 230-4, 2012 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-22424907

RESUMEN

This research consisted of two studies, the fundamental aim of which was to delineate the pattern of relationships between measures of cognitive task performance and both symptom subtypes in schizophrenia and their corresponding schizotypal personality traits in healthy individuals. Study 1 compared these relationships in healthy individuals using the Schizotypal Personality Questionnaire (SPQ) and Study 2 assessed the relationships between symptomatology assessed using the Scale for the Assessment of Positive Symptoms and Scale for the Assessment of Negative Symptoms (SAPS/SANS) and cognitive task performance in a group of patients with schizophrenia. The contribution of fluid intelligence to task performance was also examined. In Study 1 high levels of negative schizotypy were associated with reduced verbal fluency, and high levels of disorganised schizotypy were associated with reduced negative priming in the healthy participants. In Study 2, closely corresponding relationships between symptom measures and these tasks were found in the patients with schizophrenia. The associations between the symptom and cognitive measures were independent of the effects of fluid IQ on performance.


Asunto(s)
Trastornos del Conocimiento/etiología , Esquizofrenia/complicaciones , Psicología del Esquizofrénico , Trastorno de la Personalidad Esquizotípica/complicaciones , Adolescente , Adulto , Trastornos del Conocimiento/diagnóstico , Femenino , Humanos , Inteligencia , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Inventario de Personalidad , Escalas de Valoración Psiquiátrica , Análisis de Regresión , Encuestas y Cuestionarios , Adulto Joven
10.
J Pers Soc Psychol ; 102(5): 910-24, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22229459

RESUMEN

Anxiety and fear are often confounded in discussions of human emotions. However, studies of rodent defensive reactions under naturalistic conditions suggest anxiety is functionally distinct from fear. Unambiguous threats, such as predators, elicit flight from rodents (if an escape-route is available), whereas ambiguous threats (e.g., the odor of a predator) elicit risk assessment behavior, which is associated with anxiety as it is preferentially modulated by anti-anxiety drugs. However, without human evidence, it would be premature to assume that rodent-based psychological models are valid for humans. We tested the human validity of the risk assessment explanation for anxiety by presenting 8 volunteers with emotive scenarios and asking them to pose facial expressions. Photographs and videos of these expressions were shown to 40 participants who matched them to the scenarios and labeled each expression. Scenarios describing ambiguous threats were preferentially matched to the facial expression posed in response to the same scenario type. This expression consisted of two plausible environmental-scanning behaviors (eye darts and head swivels) and was labeled as anxiety, not fear. The facial expression elicited by unambiguous threat scenarios was labeled as fear. The emotion labels generated were then presented to another 18 participants who matched them back to photographs of the facial expressions. This back-matching of labels to faces also linked anxiety to the environmental-scanning face rather than fear face. Results therefore suggest that anxiety produces a distinct facial expression and that it has adaptive value in situations that are ambiguously threatening, supporting a functional, risk-assessing explanation for human anxiety.


Asunto(s)
Ansiedad/psicología , Emociones , Expresión Facial , Medición de Riesgo , Adolescente , Adulto , Anciano , Animales , Nivel de Alerta , Conducta Animal , Modelos Animales de Enfermedad , Miedo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Psicológicos , Reproducibilidad de los Resultados , Roedores , Reino Unido
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