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1.
Artigo em Inglês | MEDLINE | ID: mdl-39143369

RESUMO

Electrodermal lability is a trait-like measure of spontaneous sympathetic resting activity. In the present study, we addressed whether interindividual differences in this lability have an impact on the reaction time (RT) and on two physiological indicators of a goal-oriented sensorimotor preparation in a long-running, forewarned RT task (S1-S2 paradigm). The two indicators were the brain's contingent negative variation (CNV) and a heart rate deceleration (HRD). The interindividual differences were determined by counting spontaneous skin conductance fluctuations during a 5-min resting phase and dividing the subjects into two groups: individuals below (stable) and above (labile) the median of these fluctuations. In the task, labile individuals had a shorter RT compared with stable individuals and showed in the final phase of preparation in both physiological indicators the stronger response. Thus, lability-dependent effects in forewarned RT tasks cannot be explained by differences in stimulus-driven or passively controlled processes alone. Rather, goal-oriented, deliberately controlled processes that serve to adequately prepare for an imperative stimulus-the S2 in our paradigm-also must be considered to explain them. Labile individuals not only react faster than stable ones but also intentionally prepare themselves more appropriately for the imperative stimulus. A norepinephrine hypothesis focusing on the tonic activity of the locus coeruleus (LC) is proposed as an explanation for these and other lability-dependent effects. The frequency of spontaneous electrodermal fluctuations at rest may represent a peripheral, noninvasive, and easily measurable indicator of the baseline LC activity during wakefulness.

2.
Cogn Emot ; 38(6): 954-962, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38554265

RESUMO

Features of threatening cues and the associated context influence the perceived imminence of threat and the defensive responses evoked. To provide additional knowledge about how the directionality of a threat (i.e. directed-towards or away from the viewer) might impact defensive responses in humans, participants were shown pictures of a man carrying a gun (threat) or nonlethal object (neutral) directed-away from or towards the participant. Cardiac and electrodermal responses were collected. Compared to neutral images, threatening images depicting a gun directed-towards the participant induced sustained bradycardia and an increased electrodermal response, interpreted as immobility under attack. This defensive immobility reaction is evoked by high perceived threat and inescapable situations and indicates intense action preparation. Pictures of guns directed-away from the participant induced shorter bradycardia and no significant modulation of the electrodermal response compared to neutral pictures, which might be consistent with the perception of a less threatening situation. The results show that the directionality of threat stimuli is a key factor that prompts different patterns of defensive responses.


Assuntos
Medo , Resposta Galvânica da Pele , Frequência Cardíaca , Humanos , Resposta Galvânica da Pele/fisiologia , Masculino , Feminino , Frequência Cardíaca/fisiologia , Adulto , Adulto Jovem , Medo/fisiologia , Medo/psicologia , Estimulação Luminosa , Sinais (Psicologia)
3.
Addict Biol ; 25(1): e12712, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30672054

RESUMO

Research in memory reconsolidation has raised hope for new treatment options of persistent psychiatric disorders like substance dependence and post-traumatic stress disorder (PTSD). While animal research showed successful memory modification by interfering with reconsolidation, human research requires less invasive techniques. In our pilot study, we aimed to reduce appetitive memory reconsolidation of a newly acquired reward memory by exerting a stressor. Thirty healthy participants were randomly assigned to two groups performing a monetary reward paradigm at a personal computer. Day 1 was considered to allow for memory acquisition; on day 2, the experimental group was exposed to a frightening stimulus in the reconsolidation window; and day 3 again served to determine reward memory effects. Measures of reward memory were reaction times to reward announcing stimuli (ie, showing instrumental behavior), actual reward gained, and electrodermal response as a measure for reward anticipation. We found significantly smaller reaction time improvements to reward stimuli over time in the experimental group, as well as reduced achievements in monetary reward. Electrodermal response to reward announcing stimuli was lower in the experimental group after intervention, whereas it was higher in the untreated group. Thus, we argue in favor of the reconsolidation hypothesis, assuming our intervention had successfully interfered with the reconsolidation process. This points towards future treatment options that interfere with an addiction memory.


Assuntos
Condicionamento Psicológico/fisiologia , Memória/fisiologia , Recompensa , Estresse Psicológico/fisiopatologia , Adolescente , Adulto , Eletrocardiografia , Medo , Feminino , Resposta Galvânica da Pele/fisiologia , Humanos , Hidrocortisona/metabolismo , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Tempo de Reação/fisiologia , Saliva/metabolismo , Estresse Psicológico/metabolismo , Adulto Jovem
4.
Appl Psychophysiol Biofeedback ; 41(4): 375-380, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27272970

RESUMO

Six children with Attention Deficit Hyperactivity Disorder (ADHD) and five control children between the ages of 9 and 11 years were administered an adapted version of the Iowa Gambling Task while measuring anticipatory electrodermal response (EDR). Anticipatory EDR measures were compared between groups. Results indicate that the ADHD group exhibited significantly lower autonomic reactivity to anticipated consequences, evidencing a neuropsychological profile similar to patients with lesions in the ventromedial prefrontal cortex.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Resposta Galvânica da Pele/fisiologia , Estudos de Casos e Controles , Criança , Comportamento de Escolha/fisiologia , Jogo de Azar , Humanos , Masculino , Córtex Pré-Frontal/patologia , Probabilidade
5.
Physiol Behav ; 263: 114119, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36787812

RESUMO

Eye contact with another person (social gaze) can evoke emotions, produce autonomic arousal, and influence behavior. Gaze cues can be evocative even when presented in static pictures of faces suggesting that responses depend on low-level visual features of gaze stimuli. The current study examined whether emotional gaze responses depend on the physical stimulus properties of an eye contact experience versus the cognitive evaluation of the social context of gaze. This was done by comparing skin conductance responses (SCR), an index of emotional arousal, during episodes of social gaze and 'self-gaze' (gazing at one's own eyes in a mirror), keeping other aspects of the viewing conditions constant. We compared SCRs during social gaze and self-gaze in forty participant pairs. Each participant engaged in ten, 20 second eye contact trials, alternating between social and self-gaze. Self-gaze episodes produced significant SCRs but social gaze SCR's were larger and occurred more reliably. SCRs decreased across trials (habituation effect) in both conditions. We speculated that social gaze between opposite sex partners might yield larger SCRs but this was not found. Overall, these results conceptually replicate previous findings of (likely top-town) cognitive regulation of autonomic gaze responses based on evaluation of the social context.


Assuntos
Emoções , Fixação Ocular , Humanos , Emoções/fisiologia , Nível de Alerta/fisiologia , Meio Social , Olho
6.
J Interpers Violence ; 37(3-4): NP2056-NP2075, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-32597723

RESUMO

Bullying at school is a serious social problem that influences the wellbeing of everyone involved, that is, victims, perpetrators, and bystanders. Among the many health and psychological problems that these individuals may develop, emotion dysregulation appears to be a common marker. To date, however, it remains unclear whether bullying experienced during the school years is associated with emotion dysregulation also in adulthood. In this study, by adopting a retrospective approach, we investigated whether involvement in bullying at school-either as a bully, victim, or bystander-could put these individuals at risk of presenting deficits in emotion regulation in adulthood, as assessed with behavioral (explicit) and physiological (implicit) indexes (i.e., skin conductance), and whether the association between the involvement in bullying and emotion regulation was direct or mediated by other factors, such as somatic complaints and sensation seeking. A total of 58 young adults were asked to control their emotional reactions in front of images with strong emotional content, and to explicitly evaluate them with ratings, while their arousal was measured through skin conductance. They also responded to questionnaires about retrospective involvement in bullying, somatic complaints, and sensation seeking. Results revealed that victimization and bystander behavior were directly and negatively associated with emotion regulation as assessed with skin conductance, whereas bullying was positively associated with implicit emotion regulation through the mediation of sensation seeking. Interestingly, emotion regulation as assessed with explicit ratings was not associated with any of the characteristics of the participants. Our study suggests that being directly (as victim) but also indirectly (as bystander) involved in bullying at school time is associated with difficulties in emotional wellbeing in adulthood. Furthermore, it reveals that behavioral and physiological indexes associated with emotion regulation dissociate, suggesting that subtle physiological changes may remain hidden from explicit behavior.


Assuntos
Bullying , Vítimas de Crime , Regulação Emocional , Adulto , Humanos , Estudos Retrospectivos , Estudantes , Adulto Jovem
7.
Front Hum Neurosci ; 15: 763582, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34955787

RESUMO

The purpose of the present study was to elucidate whether the sympathetic response to perturbation in stance represents multiple mental responses, whether perturbation-induced fear of fall is one of the mental responses, and whether the sympathetic response is task specific. While healthy humans maintained stance, the support surface of the feet translated in the forward or backward direction. The phasic electrodermal response (EDR), representing the sympathetic response, appeared 1-1.5 s after the support surface translation. Mostly, perturbation-induced EDRs comprised one peak, but some EDRs were comprised of two peaks. The onset latency of the two-peak EDR was much shorter than that of the one-peak EDR. The second peak latency of the two-peak EDR was similar to the peak latency of the one-peak EDR, indicating that the first peak of the two-peak EDR was an additional component preceding the one-peak EDR. This finding supports a view that perturbation-induced EDR in stance sometimes represents multiple mental responses. The amplitude of the EDR had a positive and significant correlation with fear, indicating that perturbation-induced EDR in stance partially represents perturbation-induced fear of fall. The EDR amplitude was dependent on the translation amplitude and direction, indicating that perturbation-induced EDR in stance is a task specific response. The EDR appeared earlier when the participants prepared to answer a question or when the perturbation was self-triggered, indicating that adding cognitive load induces earlier perturbation-induced mental responses.

8.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 70(2): e20230742, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1529382

RESUMO

SUMMARY OBJECTIVE: Sudden unexpected death in epilepsy is the most common cause of death in young patients with epilepsy. The aim of this study was to evaluate changes in interictal electrocardiogram parameters and sympathetic skin responses as markers of autonomic dysfunction in patients with epilepsy and to determine their effects on the type and duration of epilepsy, frequency of seizures, and responses to treatment. METHODS: A total of 97 patients with epilepsy and 94 healthy controls were recruited. We recorded their clinical and demographic characteristics and analyzed sympathetic skin response latency and amplitude, electrocardiogram recordings, and seven cardiac rhythm parameters: P-wave duration, PR segment, QRS duration, QT interval, QT interval distribution, Tpe duration, and Tpe/QT interval ratio. RESULTS: P-wave durations, T-wave durations, QT and QT interval durations, and Tpe and sympathetic skin response latency were significantly longer among patients with epilepsy than the controls, and their heart rate was significantly lower. However, sympathetic skin response latency and heart rate were negatively correlated, and T-wave duration, QT duration, QT interval duration, and Tpe were positively correlated. CONCLUSION: Our results from interictal electrocardiograms indicate clinically significant arrhythmias among patients with epilepsy and the correlation of such arrhythmias with sympathetic skin responses. Thus, noninvasive tests that evaluate the autonomic system should be used to predict the risk of sudden unexpected death in epilepsy among patients with epilepsy.

9.
JMIR Pediatr Parent ; 1(1): e1, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30637376

RESUMO

Background: Many adolescent mothers are parenting young children under highly stressful conditions as they are managing first-time parenthood, poverty, lack of housing, school and work, and challenging peer and familial relationships. Mobile health (mHealth) technology has the potential to intervene at various points in the emotion regulation process of adolescent mothers to provide them support for more adaptive emotional and behavioral regulation in the course of their daily life. Objective: The goal of this study was to examine the acceptability, feasibility, use patterns, and mechanisms by which a mobile technology used as an adjunct to in-person, provider-delivered sessions fostered adolescent mothers' adaptive emotion regulation strategies under real-life conditions. Methods: Participants (N=49) were enrolled in the intervention condition of a larger pilot study of homeless adolescent mothers living in group-based shelters. The mHealth technology. Calm Mom, consisted of a mobile app and a wrist-worn sensorband for the ambulatory measurement and alerting of increased electrodermal activity (EDA), a physiological measurement of stress. We examined logs of mobile app activity and conducted semistructured qualitative interviews with a subsample (N=10) of participants. Qualitative data analysis was guided by the theoretical frames of the intervention and a technology acceptance model and included an analysis of emerging themes and concepts. Results: Overall, participants indicated that one or more of the elements of Calm Mom supported their ability to effectively regulate their emotions in the course of their daily life in ways that were consonant with the intervention's theoretical model. For many adolescent mothers, the app became an integral tool for managing stress. Due to technical challenges, fewer participants received sensorband alerts; however, those who received alerts reported high levels of acceptability as the technology helped them to identify their emotions and supported them in engaging in more adaptive behaviors during real-life stressful situations with their children, peers, and family members. Conclusions: Calm Mom is a promising technology for providing theoretically driven behavioral intervention strategies during real-life stressful moments among a highly vulnerable population. Future research efforts will involve addressing technology challenges and refining tailoring algorithms for implementation in larger-scale studies.

10.
Behav Res Ther ; 109: 68-74, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30120999

RESUMO

Although contemporary treatments for anxiety disorders are very efficient in reducing anxiety, return of fear after successful treatment is common which signifies a need for interventions that have a more enduring outcome. A recent laboratory study suggested that novelty-facilitated extinction, a simple modification of standard extinction which involves presenting a novel non-aversive stimulus during extinction, prevents spontaneous recovery, one laboratory analogue of return of fear. The current study assessed whether novelty-facilitated extinction can also prevent reinstatement, a second laboratory analogue of return of fear. Following differential fear conditioning, one group of participants underwent standard extinction training whereas the second was presented with a novel tone after the conditional stimulus that previously predicted the aversive unconditional stimulus (US). Three presentations of the USs alone reinstated differential electrodermal fear responses after standard extinction, but not after novelty-facilitated extinction. Moreover, replicating previous findings, the extent of return of fear was correlated with self-reported intolerance of uncertainty after standard extinction, but not after novelty-facilitated extinction. These results support the proposal that novelty-facilitated extinction training can reduce the extent of return of fear.


Assuntos
Condicionamento Clássico/fisiologia , Comportamento Exploratório/fisiologia , Extinção Psicológica/fisiologia , Medo/fisiologia , Adolescente , Adulto , Feminino , Resposta Galvânica da Pele/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Incerteza , Adulto Jovem
11.
Front Hum Neurosci ; 11: 342, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28706480

RESUMO

In this paper, we examined brain activation in subjects during two music listening conditions: listening while simultaneously rating the musical piece being played [Listening and Rating (LR)] and listening to the musical pieces unconstrained [Listening (L)]. Using these two conditions, we tested whether the sequence in which the two conditions were fulfilled influenced the brain activation observable during the L condition (LR → L or L → LR). We recorded high-density EEG during the playing of four well-known positively experienced soundtracks in two subject groups. One group started with the L condition and continued with the LR condition (L → LR); the second group performed this experiment in reversed order (LR → L). We computed from the recorded EEG the power for different frequency bands (theta, lower alpha, upper alpha, lower beta, and upper beta). Statistical analysis revealed that the power in all examined frequency bands increased during the L condition but only when the subjects had not had previous experience with the LR condition (i.e., L → LR). For the subjects who began with the LR condition, there were no power increases during the L condition. Thus, the previous experience with the LR condition prevented subjects from developing the particular mental state associated with the typical power increase in all frequency bands. The subjects without previous experience of the LR condition listened to the musical pieces in an unconstrained and undisturbed manner and showed a general power increase in all frequency bands. We interpret the fact that unconstrained music listening was associated with increased power in all examined frequency bands as a neural indicator of a mental state that can best be described as a mind-wandering state during which the subjects are "drawn into" the music.

12.
Front Psychiatry ; 7: 130, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27507949

RESUMO

A large number of individuals experience mental health disorders, with cognitive behavioral therapy (CBT) emerging as a standard practice for reduction in psychiatric symptoms, including stress, anger, anxiety, and depression. However, CBT is associated with significant patient dropout and lacks the means to provide objective data regarding a patient's experience and symptoms between sessions. Emerging wearables and mobile health (mHealth) applications represent an approach that may provide objective data to the patient and provider between CBT sessions. Here, we describe the development of a classifier of real-time physiological stress in a healthy population (n = 35) and apply it in a controlled clinical evaluation for armed forces veterans undergoing CBT for stress and anger management (n = 16). Using cardiovascular and electrodermal inputs from a wearable device, the classifier was able to detect physiological stress in a non-clinical sample with accuracy greater than 90%. In a small clinical sample, patients who used the classifier and an associated mHealth application were less likely to discontinue therapy (p = 0.016, d = 1.34) and significantly improved on measures of stress (p = 0.032, d = 1.61), anxiety (p = 0.050, d = 1.26), and anger (p = 0.046, d = 1.41) compared to controls undergoing CBT alone. Given the large number of individuals that experience mental health disorders and the unmet need for treatment, especially in developing nations, such mHealth approaches have the potential to provide or augment treatment at low cost in the absence of in-person care.

13.
Front Behav Neurosci ; 9: 178, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26217205

RESUMO

The specific role of the amygdala remains controversial even though the development of functional imaging techniques has established its implication in the emotional process. The aim of this study was to highlight the sensitivity of the amygdala to emotional intensity (arousal). We conducted an analysis of the modulation of amygdala activation according to variation in emotional intensity via an fMRI event-related protocol. Monitoring of electrodermal activity, a marker of psychophysiological emotional perception and a reflection of the activation of the autonomic nervous system, was carried out concurrently. Eighteen subjects (10 men; aged from 22 to 29 years) looked at emotionally positive photographs. We demonstrated that the left and right amygdalae were sensitive to changes in emotional intensity, activating more in response to stimuli with higher intensity. Furthermore, electrodermal responses were more frequent for the most intense stimuli, demonstrating the concomitant activation of the autonomic nervous system. These results highlight the sensitivity of the amygdala to the intensity of positively valenced visual stimuli, and in conjunction with results in the literature on negative emotions, reinforce the role of the amygdala in the perception of intensity.

14.
Front Psychol ; 6: 983, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26217293

RESUMO

Recent empirical findings suggest that alcohol dependence is characterized by heightened sensitivity to unfairness during social transactions. The present study went a step further and aimed to ascertain whether this abnormal level of sensitivity to unfairness is underlined by an increased emotional reactivity. Twenty-six recently abstinent alcohol-dependent (AD) individuals and 32 controls performed an ultimatum game (UG), in which participants had to respond to take-it-or-leave-it offers, ranging from fair to unfair and made by a fictive proposer. Emotional state was recorded during UG offers presentation and was indexed by the amplitude of skin conductance response (SCR). Results showed that AD decided to reject unfair offers more frequently than their controls, confirming previous data. The proportion of rejected unfair UG offers was correlated with SCR, in the AD but not in the control group. This finding suggests that deciding to accept or reject unfair UG offers is influenced by arousal-affective activity in AD, but not in controls. Heightened emotional reactivity may have driven AD to punish the proposer rather than acting as a rational economic agent. An implication of present findings is that AD might have difficult to cope with unfair situations triggered by social interactions. Future studies are needed in order to examine whether-emotional and behavioral-reactivity to unfairness during the UG could impact alcohol consumption and relapse in AD.

15.
Front Hum Neurosci ; 9: 401, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26257624

RESUMO

While previous studies have analyzed mean neurophysiological responses to musical stimuli, the current study aimed to identify specific time courses of electroencephalography (EEG) oscillations, which are associated with dynamic changes in the acoustic features of the musical stimulus. In addition, we were interested in whether these time courses change during a repeated presentation of the same musical piece. A total of 16 subjects repeatedly listened to the well-known aria "Nessun dorma," sung by Paul Potts, while continuous 128-channel EEG and heart rate, as well as electrodermal responses, were recorded. The time courses for the EEG oscillations were calculated using a time resolution of 1 second for several frequency bands, on the basis of individual alpha-peak frequencies (theta, low alpha-1, low alpha-2, upper alpha, and beta). For all frequency bands, we identified a more or less continuous increase in power relative to a baseline period, indicating strong event-related synchronization (ERS) during music listening. The ERS time courses, however, did not correlate strongly with the time courses of the acoustic features of the aria. In addition, we did not observe changes in EEG oscillations after repeated presentation of the same musical piece. Aside from this distinctive feature, we identified a remarkable variability in EEG oscillations, both within and between the repeated presentations of the aria. We interpret the continuous increase in ERS observed in all frequency bands during music listening as an indicator of a particular neurophysiological and psychological state evoked by music listening. We suggest that this state is characterized by increased internal attention (accompanied by reduced external attention), increased inhibition of brain networks not involved in the generation of this internal state, the maintenance of a particular level of general alertness, and a type of brain state that can be described as "mind wandering." The overall state can be categorized as a psychological process that may be seen as a "drawing in" to the musical piece. However, this state is not stable and varies considerably throughout the music listening session and across subjects. Most important, however, is the finding that the neurophysiological activations occurring during music listening are dynamic and not stationary.

16.
Psychophysiology ; 52(1): 8-19, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25252169

RESUMO

Skin conductance (SC) reflects stimulus significance and can be measured by integrating electrodes directly onto a smartphone housing such that they are naturally contacted when gripped. However, grip artifacts naturally arise during operation since grip forces can vary. We explored the effects of grip force on SC to determine feasibility and to draw guidelines on artifact mitigation. For this purpose, a prototype was built with integrated SC electrodes with colocated force sensors, and data was collected from 24 participants gripping the prototype across different grip force conditions. Our analysis showed that static forces greater than 2.0 N were associated with significant SC distortion, and artifacts induced from dynamic grip forces were buffered if the SC level was at least 1.1 microsiemens. Our findings are relevant for future applications of SC sensing on smartphones, which may enable interesting and highly contextual user experiences.


Assuntos
Computadores de Mão , Eletrodos , Resposta Galvânica da Pele/fisiologia , Força da Mão/fisiologia , Monitorização Ambulatorial/instrumentação , Adolescente , Adulto , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Smartphone , Adulto Jovem
17.
Biol Psychol ; 103: 242-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25291557

RESUMO

Oppositionality encompasses distinct dimensions, and few studies have investigated the validity of such distinctions from a pathophysiological perspective. Our aim was to investigate the association between sympathetic skin responses (SSR) and distinct oppositional dimensions in a community sample of adolescents. Forty adolescents aged 13.84±1.46 years participated in this study. Oppositionality was measured by externalizing behavior and bullying scores (dependent variables), while SSR was recorded by electrical changes at the skin level (independent variables). Results showed that increased SSRs were associated with oppositionality; however, these associations were specific to the headstrong/hurtful dimension. Further exploratory analyses demonstrated that increased SSRs were associated with several types of headstrong/hurtful behaviors and underscore the importance of the first aversive stimuli to differentiate groups with low and high headstrong/hurtful behaviors. There were no differences between groups regarding time until habituation. This study provides insights about how dysfunctions in autonomic balance may contribute to the emergence of oppositional behavior among adolescents.


Assuntos
Transtornos de Deficit da Atenção e do Comportamento Disruptivo/fisiopatologia , Bullying , Resposta Galvânica da Pele/fisiologia , Sistema Nervoso Simpático/fisiologia , Adolescente , Agressão , Criança , Feminino , Humanos , Masculino , Sistema Nervoso Simpático/fisiopatologia
18.
Brain Res ; 1557: 141-54, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24530267

RESUMO

The study measured cortical hemodynamic signals and peripheral correlates of decision makers during a dynamic risky task, the Just One More task (JOM), in which the risky decision entails choosing whether to incrementally increase accumulated earnings at the risk of ruin (going bust ending up with nothing). Twenty subjects participated in multiple instantiations of this task in which the probability of ruin and size of the stakes varied. Physiological correlates were simultaneously quantified by functional near-infrared spectroscopy (fNIRS) over dorsolateral prefrontal cortex (DLPFC) and electrodermal activity (EDA). First, in the task decision phase (i.e., when subjects are contemplating options before making a choice) probability of ruin had a dissociating effect on fNIRS and EDA. fNIRS derived DLPFC hemodynamic signals reflected a subjective value signal, correlating positively with individual risk attitude. Contrary, EDA reflected the probability of ruin in terms of a common affective measure, irrespective of individuals׳ risk attitude. Second, during the task outcome phase (i.e., the time after subjects have made a choice and observed the outcomes) fNIRS and EDA revealed opposite patterns. While fNIRS derived DLPFC hemodynamic signals were larger in response to gains, EDA signals were larger in response to losses; both patterns were statistically independent of individual risk attitude. Lastly, fNIRS derived DLPFC hemodynamic signals in the decision phase correlated positively with the mean round earnings, providing a measure of the quality of the individual decision-making performance. Together with the positive correlation with individual risk attitude, our findings indicate that fNIRS signals, but not EDA, could be taken as a useful method for studying individual risk attitude and task performance in dynamic risky decision-making.


Assuntos
Atitude , Circulação Cerebrovascular/fisiologia , Tomada de Decisões/fisiologia , Resposta Galvânica da Pele/fisiologia , Córtex Pré-Frontal/fisiologia , Risco , Adulto , Retroalimentação Psicológica/fisiologia , Feminino , Humanos , Individualidade , Modelos Lineares , Masculino , Testes Neuropsicológicos , Córtex Pré-Frontal/irrigação sanguínea , Probabilidade , Espectroscopia de Luz Próxima ao Infravermelho , Análise e Desempenho de Tarefas
19.
Physiol Behav ; 135: 215-21, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24976454

RESUMO

The fast and reliable neuronal and behavioral responses to negative affective stimuli have been suggested to be at least partly based on the processing of simple geometric configurations within complex visual stimuli. In this context, one line of experimental and neuroimaging evidence suggests that simple V-shaped stimuli result in patterns of neuronal activation and behavioral responses akin to pictures of negative facial expressions. The present study investigated the effects of circles as well as upward and downward pointing triangles in healthy young adults on three peripheral physiological markers - skin conductance response (SCR), facial EMG, and startle reflex - in order to further narrow the gap between neuroimaging findings and behavioral data regarding the impact of geometric shapes. We found significant effects of geometric forms on the startle reflex (p≤0.001, η(2)=0.080) and the SCR (p=0.029, η(2)=0.078), but not on facial EMG. Furthermore, subjective valence and arousal ratings of geometric stimuli differed significantly, with downward pointing triangles being perceived as less pleasant and more arousing. In sum, our findings provide further evidence that simple geometric shapes convey emotional meaning. Particularly, the observed changes in SCR and startle response underscore the notion that geometric shapes lead to preparatory changes in physiological activation patterns, which are essential for facilitation of appropriate behavioral responses. However, the smaller effect sizes compared to more realistic affective pictures also highlight the organisms' ability to differentiate between real impending danger and abstract cues in order to avoid unnecessary excessive responses.


Assuntos
Atenção/fisiologia , Músculos Faciais/fisiologia , Percepção de Forma/fisiologia , Resposta Galvânica da Pele/fisiologia , Reflexo de Sobressalto/fisiologia , Adolescente , Adulto , Afeto/fisiologia , Nível de Alerta/fisiologia , Eletromiografia , Emoções/fisiologia , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto Jovem
20.
Autism Res ; 6(6): 494-505, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23893954

RESUMO

In this study, we explore reward-based decision making and electrodermal responding (EDR) among children with autism spectrum disorder (ASD) during a children's gambling task. In addition, we examine whether individual behavioral and EDR responses predict social communication, repetitive symptoms, parent reports of executive function, and behavioral challenges. The ability to form advantageous strategies for long-term gain is of interest for children with ASD, who exhibit both difficulty with executive function and atypical responses to reward. Twenty-one children ages 6-7 years with ASD and no intellectual disability, and 21 age- and IQ-matched typically developing children participated. Both groups exhibited a similar pattern of gambling selections, but children with ASD showed less knowledge of the reward contingencies of the decks after playing. In addition, although EDR was similar between groups in anticipation of selections, children with ASD exhibited greater EDR during feedback about rewards as the task progressed. Children with ASD who exhibited the greatest increases in EDR were more likely to exhibit repetitive symptoms, particularly rituals and the need for sameness, as well as internalizing behaviors and reduced executive function in other settings.


Assuntos
Comportamento Infantil/psicologia , Transtornos Globais do Desenvolvimento Infantil/psicologia , Tomada de Decisões/fisiologia , Resposta Galvânica da Pele/fisiologia , Jogo de Azar/psicologia , Recompensa , Criança , Comunicação , Função Executiva/fisiologia , Feminino , Humanos , Controle Interno-Externo , Masculino , Comportamento Social , Análise e Desempenho de Tarefas
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