Effects of dilemmas and aromas on performance of the Iowa Gambling Task

Enhancing cognitive control of our decisions: Making the most of humor during the IGT in females and males

We studied the impact of humor on the Iowa Gambling Task (IGT) decision-making performance and the cognitive control exerted during this task, considering sex as a moderator, and examined whether cognitive control mediated the influence of humor on decision-making. Sixty participants (30 females) performed an extended version of the IGT (500 trials divided into 20 blocks). We randomly assigned them to either an experimental group (Humor Group; Hg; n = 30), where humorous videos were interspersed in the decision-making trials or a control group (Non-Humor Group; NHg; n = 30), where nonhumorous videos were interspersed in the decision-making trials. We recorded participant performance and feedback-related negativity (FRN) and P3b event-related potentials (ERP) during IGT feedback as task monitoring and attention allocation indicators, respectively. We expected that whereas humor would improve IGT decision-making under risk in females during the last blocks (17-20) as well as cognitive control (specifically attention allocation and task monitoring) across the entire IGT, it would impair them in males. Contrary to our expectations, humor improved IGT decision-making under risk for both sexes (specifically at blocks 19 and 20) and attention allocation for most IGT blocks (P3b amplitudes). However, humor impaired IGT decision-making under ambiguity in males during the block six and task monitoring (FRN amplitudes) for most IGT blocks. Attention allocation did not mediate the beneficial effect of humor on decision-making under risk in either sex. Task monitoring decrements fully mediated the humor's detrimental influence on men's decision-making under ambiguity during block six.

FRN and P3 during the Iowa gambling task: The importance of gender

Previous research has shown gender-related psychobiological differences in risky and competitive strategies that affect win and loss outcomes. In addition, some studies have found differences in the decision-making process, with women taking longer to reach the same performance as men. However, the underlying neural mechanisms remain unclear. The present study aimed to investigate gender differences in behavioral performance and neural correlates during a decision-making task, the Iowa Gambling Task (IGT). Forty healthy young adults (23 men and 17 women) performed the IGT while the feedback-related negativity (FRN) and P3 were recorded as neural correlates of feedback processing. No gender differences were observed in the behavioral performance on the IGT after 100 and 150 trials, or in the P3 component. In women, but not in men, the FRN component showed a greater amplitude for losses than for wins. There were no significant gender-related differences in behavioral performance, and men and women revealed a similar learning process on the IGT. At the neural level, no direct differences between men and women were observed in the feedback processing stage for the FRN or P3. However, our results indicate that women showed greater sensitivity to losses than to wins during the decision-making task, as reflected in the FRN component.

Country and Sex Differences in Decision Making Under Uncertainty and Risk

Whether males and females differ in decision-making remains highly debatable. However, a male advantage in decision making is observed in animal as well as human models of the iowa gambling task (IGT), and, in case of the latter, the difference is observed across a wide range of age groups. It is unclear if these sex differences on the IGT are malleable to environmental influences such as sociocultural factors. We tested sex differences during the uncertainty and risk phases of the IGT in data pooled from three countries that reflected high, moderate, to low gender-equity (Germany, United States, and India: N = 531, female = 269). Comparing the net scores in uncertainty vs. risk blocks (first two vs. last two blocks) confirmed the male-advantage on the IGT across the three countries, specifically in the risk blocks, with the highest male-advantage observed for Germany. Results are discussed in terms of sex differences in reaction to uncertainty vs. risk, and the counter-intuitive effect of gender-equitable environment suggesting that national/environmental factors might influence advantageous decision making, but in ways that accentuate rather than abate sex differences.

Humor Improves Women's but Impairs Men's Iowa Gambling Task Performance

The Iowa Gambling Task (IGT) is a popular method for examining real-life decision-making. Research has shown gender related differences in performance, in that men consistently outperform women. It has been suggested that these performance differences are related to decreased emotional control in women compared to men. Given the likely role of emotion in these gender differences, in the present study, we examine the effect of a humor induction on IGT performance and whether the effect of humor is moderated by gender. IGT performance and parameters from the Expectancy Valence Model (EVM) were measured in 68 university students (34 men; mean age 22.02, SD = 4.3 and 34 women; mean age 22.3, SD = 4.1) during a 100 trial-IGT task. Participants were exposed to a brief video before each of the IGT decisions available; one half of the samples (17 men and 17 women) was exposed to 100 humor videos, while the other half was exposed to 100 non-humor videos during the task. We observed a significant interaction between gender and humor, such that under humor, women's performance during the last block (trials 80-100) improved (compared to women under non-humor), whereas men's performance during the last block was worse (compared to men under non-humor). Consistent with previous work, under non-humor, men outperformed women in the last block. Lastly, our EVM results show that humor impacts the learning mechanisms of decision-making differently in men and women. Humor impaired men's ability to acquire knowledge about the payoff structure of the decks, and as a consequence, they were stuck in suboptimal performance. On the other hand, humor facilitated women's ability to explore and to learn from experience, improving performance. These findings deepen our understanding of the mechanisms underlying IGT decision-making and differential effects of humor in men and women.

Gender differences in preference for reward frequency versus reward magnitude in decision-making under uncertainty

Extensive research has focused on gender differences in intertemporal choices made from description in which participants must choose from multiple options that are specified without ambiguity. However, there has been limited work examining gender differences in intertemporal choices made from experience in which the possible payoffs among choice alternatives are not initially known and can only be gained from experience. Other work suggests that females attend more to reward frequency, whereas males attend more to reward magnitude. However, the tasks used in this research have been complex and did not examine intertemporal decision-making. To specifically test whether females are more sensitive to reward frequency and males are more sensitive to reward magnitude on intertemporal decisions made from experience, we designed a simple choice task in which participants pressed a response button at a time of their own choosing on each of many trials. Faster responses led to smaller, but more frequent rewards, whereas slower responses led to larger, but less frequently given rewards. As predicted, females tended to respond quicker for more certain, smaller rewards than males, supporting our prediction that women attend more to reward frequency whereas men attend more to reward magnitude.

Dopamine and Stress System Modulation of Sex Differences in Decision Making

Maladaptive decision making is associated with several neuropsychiatric disorders, including problem gambling and suicidal behavior. The prevalence of these disorders is higher in men vs women, suggesting gender-dependent regulation of their pathophysiology underpinnings. We assessed sex differences in decision making using the rat version of the Iowa gambling task. Female rats identified the most optimal choice from session 1, whereas male rats from session 5. Male, but not female rats, progressively improved their advantageous option responding and surpassed females. Estrus cycle phase did not affect decision making. To test whether pharmacological manipulations targeting the dopaminergic and stress systems affect decision making in a sex-dependent manner, male and female rats received injections of a dopamine D₂ receptor (D₂R) antagonist (eticlopride), D₂R agonist (quinpirole), corticotropin-releasing factor 1 (CRF₁) antagonist (antalarmin), and α₂-adrenergic receptor antagonist (yohimbine; used as a pharmacological stressor). Alterations in mRNA levels of D₂R and CRF₁ were also assessed. Eticlopride decreased advantageous responding in male, but not female rats, whereas quinpirole decreased advantageous responding specifically in females. Yohimbine dose-dependently decreased advantageous responding in female rats, whereas decreased advantageous responding was only observed at higher doses in males. Antalarmin increased optimal choice responding only in female rats. Higher Drd2 and Crhr1 expression in the amygdala were observed in female vs male rats. Higher amygdalar Crhr1 expression was negatively correlated with advantageous responding specifically in females. This study demonstrates the relevance of dopaminergic- and stress-dependent sex differences to maladaptive decision making.

A gaze bias with coarse spatial indexing during a gambling task

Researchers have used eye-tracking methods to infer cognitive processes during decision making in choice tasks involving visual materials. Gaze likelihood analysis has shown a cascading effect, suggestive of a causal role for the gaze in preference formation during evaluative decision making. According to the gaze bias hypothesis, the gaze serves to build commitment gradually towards a choice. Here, we applied gaze likelihood analysis in a two-choice version of the well-known Iowa Gambling Task. This task requires active learning of the value of different choice options. As such, it does not involve visual preference formation, but choice optimization through learning. In Experiment 1 we asked subjects to choose between two decks with different payoff structures, and to give their responses using mouse clicks. Two groups of subjects were exposed to stable versus varying outcome contingencies. The analysis revealed a pronounced gaze bias towards the chosen stimuli in both groups of subjects, plateauing at more than 400 ms before the choice. The early plateauing suggested that the gaze effect partially reflected eye-hand coordination. In Experiment 2 we asked subjects to give responses using a key press. The results again showed a clear gaze bias towards the chosen deck, this time without any influence from eye-hand coordination. In both experiments, there was a clear gaze bias towards the choice even though the gaze fixations did not narrowly focus on the spatial positions of choice options. Taken together, the data suggested a role for gaze in coarse spatial indexing during non-perceptual decision making.

Decision-making in unipolar or bipolar suicide attempters

OBJECTIVE

Disadvantageous decision-making (mainly measured by the Iowa Gambling Task) has been demonstrated in patients with suicidal behavior compared to controls. We, therefore, aimed at clarifying the qualitative and quantitative relationship between decision-making and the risk of suicidal behavior in unipolar and bipolar disorders respectively, as well as establishing the strength of this relationship.

METHODS

(1) We conducted a cross-sectional study comparing IGT performances between 141 unipolar suicide attempters and 57 bipolar suicide attempters. (2) We conducted a systematic review and a meta-analysis of studies comparing IGT performances in patients with vs. without a history of suicidal acts in bipolar and unipolar disorder, together and separately.

RESULTS

(1) Among suicide attempters, bipolar and unipolar groups performed similarly (t(195)=-0.7; p=0.48). Unipolar non-attempters performed better IGT than unipolar suicide attempters (t(221)=3.1; p=0.002), only in female gender, whereas performances were similar in bipolar patients whatever the history of suicide attempt (t(77)=-0.3; p=0.7). (2) A meta-analysis of 10 studies confirmed significantly impaired decision-making with a moderate effect-size (-0.38 (95% CI[-0.61--0.16]; z=-3.3; p=0.001) in unipolar disorder and (g=-0.4 (95% CI[-0.75 to -0.05]; z=-2.2; p<0.026) in bipolar disorder suicide attempters compared to unipolar and bipolar non-attempters, respectively.

LIMITATIONS

It was not possible to analyse according to the level of lethality attempt.

CONCLUSION

Overall, a strong significant association was found between decision-making and the risk of suicidal behavior in unipolar disorder and bipolar disorder. However, further neuropsychological studies need to analyse separately unipolar and bipolar disorder and to study gender differences.

Sex-dependent effects on tasks assessing reinforcement learning and interference inhibition

Increasing evidence suggests that the prefrontal cortex (PFC) is influenced by sex steroids and that some cognitive functions dependent on the PFC may be sexually differentiated in humans. Past work has identified a male advantage on certain complex reinforcement learning tasks, but it is unclear which latent task components are important to elicit the sex difference. The objective of the current study was to investigate whether there are sex differences on measures of response inhibition and valenced feedback processing, elements that are shared by previously studied reinforcement learning tasks. Healthy young adults (90 males, 86 females) matched in general intelligence completed the Probabilistic Selection Task (PST), a Simon task, and the Stop-Signal task. On the PST, females were more accurate than males in learning from positive (but not negative) feedback. On the Simon task, males were faster than females, especially in the face of incongruent stimuli. No sex difference was observed in Stop-Signal reaction time. The current findings provide preliminary support for a sex difference in the processing of valenced feedback and in interference inhibition.

Trait Anxiety Has Effect on Decision Making under Ambiguity but Not Decision Making under Risk

Previous studies have reported that trait anxiety (TA) affects decision making. However, results remain largely inconsistent across studies. The aim of the current study was to further address the interaction between TA and decision making. 304 subjects without depression from a sample consisting of 642 participants were grouped into high TA (HTA), medium TA (MTA) and low TA (LTA) groups based on their TA scores from State Trait Anxiety Inventory. All subjects were assessed with the Iowa Gambling Task (IGT) that measures decision making under ambiguity and the Game of Dice Task (GDT) that measures decision making under risk. While the HTA and LTA groups performed worse on the IGT compared to the MTA group, performances on the GDT between the three groups did not differ. Furthermore, the LTA and HTA groups showed different individual deck level preferences in the IGT: the former showed a preference for deck B indicating that these subjects focused more on the magnitude of rewards, and the latter showed a preference for deck A indicating significant decision making impairment. Our findings suggest that trait anxiety has effect on decision making under ambiguity but not decision making under risk and different levels of trait anxiety related differently to individual deck level preferences in the IGT.

Iowa Gambling Task with non-clinical participants: effects of using real + virtual cards and additional trials

Performance on the Iowa Gambling Task (IGT) in clinical populations can be interpreted only in relation to established baseline performance in normal populations. As in all comparisons of assessment tools, the normal baseline must reflect performance under conditions in which subjects can function at their best levels. In this review, we show that a number of variables enhance IGT performance in non-clinical participants. First, optimal performance is produced by having participants turn over real cards while viewing virtual cards on a computer screen. The use of only virtual cards results in significantly lower performance than the combination of real + virtual cards. Secondly, administration of more than 100 trials also enhances performance. When using the real/virtual card procedure, performance is shown to significantly increase from early adolescence through young adulthood. Under these conditions young (mean age 19 years) and older (mean age 59 years) adults perform equally. Females, as a group, score lower than males because females tend to choose cards from high-frequency-of-gain Deck B. Groups of females with high or low gonadal hormones perform equally. Concurrent tasks, e.g., presentation of aromas, decrease performance in males. Age and gender effects are discussed in terms of a dynamic between testosterone and orbital prefrontal cortex.

Computational modeling reveals distinct effects of HIV and history of drug use on decision-making processes in women

Objective

Drug users and HIV-seropositive individuals often show deficits in decision-making; however the nature of these deficits is not well understood. Recent studies have employed computational modeling approaches to disentangle the psychological processes involved in decision-making. Although such approaches have been used successfully with a number of clinical groups including drug users, no study to date has used computational modeling to examine the effects of HIV on decision-making. In this study, we use this approach to investigate the effects of HIV and drug use on decision-making processes in women, who remain a relatively understudied population.

Method

Fifty-seven women enrolled in the Women's Interagency HIV Study (WIHS) were classified into one of four groups based on their HIV status and history of crack cocaine and/or heroin drug use (DU): HIV+/DU+ (n = 14); HIV+/DU− (n = 17); HIV−/DU+ (n = 14); and HIV−/DU− (n = 12). We measured decision-making with the Iowa Gambling Task (IGT) and examined behavioral performance and model parameters derived from the best-fitting computational model of the IGT.

Results

Although groups showed similar behavioral performance, HIV and DU exhibited differential relationship to model parameters. Specifically, DU was associated with compromised learning/memory and reduced loss aversion, whereas HIV was associated with reduced loss aversion, but was not related to other model parameters.

Conclusions

Results reveal that HIV and DU have differential associations with distinct decision-making processes in women. This study contributes to a growing line of literature which shows that different psychological processes may underlie similar behavioral performance in various clinical groups and may be associated with distinct functional outcomes.

Cross-species approaches to pathological gambling: a review targeting sex differences, adolescent vulnerability and ecological validity of research tools

Decision-making plays a pivotal role in daily life as impairments in processes underlying decision-making often lead to an inability to make profitable long-term decisions. As a case in point, pathological gamblers continue gambling despite the fact that this disrupts their personal, professional or financial life. The prevalence of pathological gambling will likely increase in the coming years due to expanding possibilities of on-line gambling through the Internet and increasing liberal attitudes towards gambling. It therefore represents a growing concern for society. Both human and animal studies rapidly advance our knowledge on brain-behaviour processes relevant for understanding normal and pathological gambling behaviour. Here, we review in humans and animals three features of pathological gambling which hitherto have received relatively little attention: (1) sex differences in (the development of) pathological gambling, (2) adolescence as a (putative) sensitive period for (developing) pathological gambling and (3) avenues for improving ecological validity of research tools. Based on these issues we also discuss how research in humans and animals may be brought in line to maximize translational research opportunities.

A critical review of sex differences in decision-making tasks: focus on the Iowa Gambling Task

It has been observed that men and women show performance differences in the Iowa Gambling Task (IGT), a task of decision-making in which subjects through exploration learn to differentiate long-term advantageous from long-term disadvantageous decks of cards: men choose more cards from the long-term advantageous decks than women within the standard number of 100 trials. Here, we aim at discussing psychological mechanisms and neurobiological substrates underlying sex differences in IGT-like decision-making. Our review suggests that women focus on both win-loss frequencies and long-term pay-off of decks, while men focus on long-term pay-off. Furthermore, women may be more sensitive to occasional losses in the long-term advantageous decks than men. As a consequence hereof, women need 40-60 trials in addition before they reach the same level of performance as men. These performance differences are related to differences in activity in the orbitofrontal cortex and dorsolateral prefrontal cortex as well as in serotonergic activity and left-right hemispheric activity. Sex differences in orbitofrontal cortex activity may be due to organisational effects of gonadal hormones early in life. The behavioural and neurobiological differences in the IGT between men and women are an expression of more general sex differences in the regulation of emotions. We discuss these findings in the context of sex differences in information processing related to evolutionary processes. Furthermore we discuss the relationship between these findings and real world decision-making.

Male and female Wistar rats differ in decision-making performance in a rodent version of the Iowa Gambling Task

The Iowa Gambling Task (IGT) measures decision-making processes by simulating real-life decisions involving reward, punishment, and uncertainty of outcomes. In humans, men show more choices for the advantageous option than women. Here, we investigated sex differences in a rat model of the IGT (r-IGT). In our r-IGT mildly food-deprived rats learn to differentiate a long-term advantageous arm from a long-term disadvantageous arm differing in frequency and amount of sugar pellets as well as unpalatable but not uneatable quinine-treated sugar pellets. We also used a T-maze discrimination procedure in which rats learn to differentiate a high from a low reward arm to further explore sex differences in reward-related decision-making. In line with human data, male rats showed a stronger task progression of choices for the advantageous option than female rats. Furthermore, male rats showed more win-stay and less lose-shift behaviour in the advantageous arm as the task progressed than female rats. Whilst both male and female rats had a stronger preference for the high over the small reward arm in the T-maze, males increased this preference over sessions, whilst females did not. These data are discussed in relation to sex differences in processing rewards and punishments.

Serotonin Transporter (5-HTTLPR) Genotype and Childhood Trauma are Associated with Individual Differences in Decision Making

The factors that influence individual differences in decision making are not yet fully characterized, but convergent evidence is accumulating that implicates serotonin (5-HT) system function. Therefore, both genes and environments that influence serotonin function are good candidates for association with risky decision making. In the present study we examined associations between common polymorphisms in the serotonin transporter gene (SLC6A4; 5-HTTLPR and rs25531), the experience of childhood trauma and decision making on the Iowa gambling task (IGT) in 391 (64.5% female) healthy Caucasian adults. Homozygosity for the 5-HTTLPR L allele was associated with riskier decision making in the first block of 20 trials (i.e., decision making under ambiguity, p = 0.004). In addition, mean IGT performance was significantly worse in blocks 3–5 (i.e., decision making under risk, p ≤ 0.05) for those participants who reported experiencing higher levels of childhood trauma. Our findings add to the growing evidence that genetic variation in the 5-HT system is associated with individual differences in decision making under ambiguity; and we report that the experience of childhood trauma is associated with relatively poor decision making under risk.