Operant conditioning and the orbitofrontal cortex in schizophrenic patients: unexpected evidence for intact functioning

Positive symptoms of schizophrenia and their relationship with cognitive and emotional executive functions

BACKGROUND

Positive symptoms of schizophrenia are associated with significant difficulties in daily functioning, and these difficulties have been associated with impaired executive functions (EEFF). However, specific cognitive and socio-emotional executive deficits have not been fully established.

OBJECTIVE

The present study has several objectives. First, we aimed to examine the specific deficits in cognitive and socio-emotional EEFF in a group of patients with schizophrenia with a predominance of positive symptoms, as well as to determine if these patients present clinically significant scores in any of the three fronto-subcortical behavioral syndromes: Dorsolateral, Orbitofrontal, or Anterior Cingulate.

METHOD

The sample consisted of 54 patients, 27 with a predominance of positive symptoms, and 27 healthy controls matched for gender, age, and education. The two groups completed four cognitive and three socio-emotional EEFF tasks. In the group of patients, positive symptoms were evaluated using the scale for the Evaluation of Positive Symptoms (SANS), while the behavioral alterations associated with the three fronto-subcortical syndromes were evaluated using the Frontal System Behavior Scale (FrSBe).

RESULTS

The patients, in comparison with a control group, presented specific deficits in cognitive and socio-emotional EEFF. In addition, a high percentage of patients presented clinically significant scores on the three fronto-subcortical syndromes.

CONCLUSION

The affectation that these patients present, in terms of both cognitive and emotional components, highlights the importance of developing a neuropsychological EEFF intervention that promotes the recovery of the affected cognitive capacities and improves the social and emotional functioning of the affected patients.

Reanalyzing the Maia and McClelland (2004) Empirical Data: How Do Participants Really Behave in the Iowa Gambling Task?

Background

Since 2007, the Iowa Gambling Task (IGT) has been a standardized clinical assessment tool for assessing decision behavior in 13 psychiatric/neurological conditions. After the publication of Maia and McClelland's (1) article, there were two responses in 2005 from Bechara et al. and Maia and McClelland, respectively, discussing whether implicit emotion or explicit knowledge influences the development of foresighted decision strategies under uncertain circumstances (e.g., as simulated in the IGT).

Methods and Results

We reanalyze and verify the data obtained by Maia and McClelland (1) in their study "What participants really know in the Iowa Gambling Task" and find that decision-makers were lured into shortsighted decisions by the prospect of immediate gains and losses.

Conclusion

Although the findings of this reanalysis cannot support any arguments concerning the effect of either implicit emotion or explicit knowledge, we find evidence that, based on the gain-loss frequency in the IGT, participants behave myopically. This is consistent with most IGT-related articles (58 out of 86) in Lee et al.'s (2) cross-cultural review. Alternatively, under uncertain circumstances, there is probably no such thing as foresighted decision strategy irrespective of the proposed mechanisms of implicit emotion or explicit knowledge.

The Prominent Deck B Phenomenon in Schizophrenia: An Empirical Study on Iowa Gambling Task

Background: The Iowa Gambling Task (IGT) was established to evaluate emotion-based decision-making ability under uncertain circumstances in clinical populations, including schizophrenia (Sz). However, there remains a lack of stable behavioral measures regarding discrimination for decision-making performance in IGT between schizophrenic cases and healthy participants. None of the Sz-IGT studies has specifically verified the prominent deck B (PDB) phenomenon gradually revealed in other populations. Here, we provided a global review and empirical study to verify these Sz-IGT issues. Methods: Seeking reliable and valid behavioral measures, we reviewed 38 studies using IGT to investigate decision-making behavior in Sz groups. The IGT, the Wisconsin Card Sorting Test (WCST), and clinical symptoms evaluations were administered to 61 schizophrenia or schizoaffective cases diagnosed by psychiatrists and 62 demographically matched healthy participants. Results: There were no valid behavioral measures in IGT that could significantly identify the decision-making dysfunction of Sz. However, Sz cases, on average, made more choices from disadvantageous deck B relative to other decks, particularly in the later learning process (block 3-5). Compared to the control group, the Sz group was more impaired on the WCST. The high-gain frequency decks B and D showed significant correlations with WCST but no correlation between clinical symptoms and IGT/WCST. Conclusions: Gain-loss frequency (GLF) has a dominant and stable impact on the decision-making process in both Sz and control groups. PDB phenomenon is essentially challenging to be observed on the ground of the expected value (EV) viewpoint approach on the IGT in both populations. Consequently, caution should be exercised when launching the IGT to assess the decision-making ability of Sz under a clinical scenario.

Altered risky decision making in patients with early non-affective psychosis

Abnormal risky decision making may represent an important factor contributing to functional impairment in psychotic disorders. Previous research revealed impaired decision making under risk in patients with chronic schizophrenia. However, risky decision making is under-studied in the early course of illness. We examined risky decision making in 33 patients with early non-affective psychosis and 32 demographically matched controls, using two well-validated experimental paradigms, balloon analogue risk task (BART) and Risky-Gains task (RGT), which modeled and assessed actual risk-taking behaviors in deliberative and time-pressured decision-making situations, respectively. Our results showed that patients exhibited suboptimal decision making on the BART and were more risk averse than controls by having fewer average balloon pumps in non-burst trials, lower explosion rate and lower total points gained. On the RGT, patients also behaved more conservatively than controls, with lower overall rate in choosing the risky option. Intriguingly, patients performed comparably to controls in adjusting risk-taking pattern following punished trials, suggesting relatively preserved sensitivity to punishment in early psychosis. Risk-taking measures showed no significant correlations with any symptom dimensions, impulsivity traits, cognitive functions or antipsychotic treatment after correcting for multiple comparisons. This study is the first to investigate risk-taking propensity in early psychosis based on BART/RGT performance, and consistently indicate that patients with early psychosis displayed altered risky decision making with increased risk aversion relative to healthy participants. Further investigation is warranted to clarify the longitudinal course of aberrant risky decision making and its relationship with functional outcome in early psychosis.

Recollecting Cross-Cultural Evidences: Are Decision Makers Really Foresighted in Iowa Gambling Task?

The Iowa Gambling Task (IGT) has become a remarkable experimental paradigm of dynamic emotion decision making. In recent years, research has emphasized the "prominent deck B (PDB) phenomenon" among normal (control group) participants, in which they favor "bad" deck B with its high-frequency gain structure-a finding that is incongruent with the original IGT hypothesis concerning foresightedness. Some studies have attributed such performance inconsistencies to cultural differences. In the present review, 86 studies featuring data on individual deck selections were drawn from an initial sample of 958 IGT-related studies published from 1994 to 2017 for further investigation. The PDB phenomenon was found in 67.44% of the studies (58 of 86), and most participants were recorded as having adopted the "gain-stay loss-randomize" strategy to cope with uncertainty. Notably, participants in our sample of studies originated from 16 areas across North America, South America, Europe, Oceania, and Asia, and the findings suggest that the PDB phenomenon may be cross-cultural.

"Cool" and "Hot" Executive Functions in Patients With a Predominance of Negative Schizophrenic Symptoms

Background

Patients with psychosis often present significant neurocognitive deficits, with executive function deficits (EEFF) being one of the most relevant cognitive impairments with the greatest impact on the functioning of their daily lives. However, although various findings of executive involvement were reported, it is not entirely clear whether there is a differential pattern of involvement according to the clinical symptoms or the deficits occur in all or only in some subcomponents of EEFF.

Objective

The present study had a double objective: to study the specific deficits in the cool and hot EEFF in a group of psychotic patients with a predominance of negative symptoms; and determine the possible associations between the performance of the patients in the cool an hot EEFF tasks with the negative symptoms, and with the behavioral alterations associated with the dysexecutive syndrome.

Method

66 participants, 33 psychotic patients with a predominance of negative symptoms and 33 healthy control subjects matched in gender, age and educational level participated. Both groups were administered 4 cool EEFF tasks (coding/maintenance and updating of information in working memory, ability to change the mental set and planning), and 3 hot EEFF tasks (decision making in situations of uncertainty, recognition of emotions through facial expressions and theory of mind). In the group of patients, the Negative symptoms were evaluated through the Scale for the Evaluation of Negative Symptoms (SANS), and the behavioral alterations associated with dysexecutive syndrome through the subscale of "Executive Dysfunction" of the Frontal Systems Behavior Scale.

Results

Patients performed worse on three cool EEFF tasks and on two of the hot EEFF tasks. Additionally, we found a correlation between the SANS score and the "executive dysfunction" subscale, with the cold EEFF task that measures planning.

Conclusion

Our findings showed that in psychotic patients with a predominance of negative symptoms, both, the cognitive (cool) and emotional (hot) components of executive functions are affected. The results reinforce the need for a cognitive rehabilitation treatment of the executive components of the working memory and of those more socio-emotional aspects.

Sweating the small stuff: A meta-analysis of skin conductance on the Iowa gambling task

To systematically examine the role of anticipatory skin conductance responses (aSCRs) in predicting Iowa Gambling Task (IGT) performance. Secondly, to assess the quality of aSCR evidence for the Somatic Marker Hypothesis (SMH) during the IGT. Finally, to evaluate the reliability of current psychophysiological measurements on the IGT. Electronic databases, journals and reference lists were examined for inclusion. Data were extracted by two reviewers and validated by another reviewer, using a standardised extraction sheet along with a quality assessment. Two meta-analyses of aSCR measures were conducted to test the relationship between overall aSCR and IGT performance, and differences in aSCR between advantageous and disadvantageous decks. Twenty studies were included in this review. Quality assessment revealed that five studies did not measure anticipatory responses, and few stated they followed standard IGT and/or psychophysiological procedures. The first meta-analysis of 15 studies revealed a significant, small-to-medium relationship between aSCR and IGT performance (r= .22). The second meta-analysis of eight studies revealed a significant, small difference in aSCR between the advantageous and disadvantageous decks (r= .10); however, publication bias is likely to be an issue. Meta-analyses revealed aSCR evidence supporting the SMH. However, inconsistencies in the IGT and psychophysiological methods, along with publication bias, cast doubt on these effects. It is recommended that future tests of the SMH use a range of psychophysiological measures, a standardised IGT protocol, and discriminate between advantageous and disadvantageous decks.

Functional Cerebral Specialization and Decision Making in the Iowa Gambling Task: A Single-Case Study of Left-Hemispheric Atrophy and Hemispherotomy

The Iowa Gambling Task (IGT) is a decision-making task that preferentially involves the right prefrontal cortex (PFC). However, the performance of the task is driven by two attributes: intertemporal (long vs. short-term) and frequency-based processing of rewards-punishments, and differs over the two phases of uncertainty (early trials) and risk (later trials). Although intertemporal decision making involves the right PFC, the extent of hemispheric specialization in attribute and phase-specific decision making is unknown. Therefore, the current study assessed decision making in a patient with a uni-hemispheric disease, who underwent hemispherotomy surgery, comparing pre-surgical IGT performance (3 days prior to surgery) with post-surgical performance (1 month, and 12 months post-surgery). The patient’s pre- and post-surgical IGT performances were analyzed to examine changes in attribute and phase-specific decision making, including the widely reported deck B phenomenon. The results for the two attributes of deck selection at the pre- and post-surgical assessments suggested marked changes in the two IGT phases of risk and uncertainty. Pre-surgery, the patient made more intertemporally disadvantageous choices, and task-progression contributed to it; within 1 month of surgery, intertemporal disadvantageous deck choices were contingent on task progression, after 1 year, disadvantageous choices were independent of task progression. Intertemporal attribute alteration was unresponsive to uncertainty and risk phase. The effect of task progression on frequency attribute remained unchanged before and immediately after the surgery, and preference for infrequent decks was observed only after 1 year. Further, pre and post surgery alteration in frequency attribute was phase-specific: within 1 month of surgery, infrequent deck choices decreased in uncertainty and increased in risk, whereas the reverse was observed after 12 months. Deck B choice increase was in the uncertainty phase. Results are discussed in reference to valence-linked hemispheric specialization and its potential role in attribute and phase-specific IGT decision making.

Reward-driven decision-making impairments in schizophrenia

The ability to use feedback to guide optimal decision-making is essential for goal-directed behaviour. While impairments in feedback-driven decision-making have been associated with schizophrenia and depression, this has been examined primarily in the context of binary probabilistic choice paradigms. In real-world decision-making, however, individuals must make choices when there are more than two competing options that vary in the frequency and magnitude of potential rewards and losses. Thus, the current study examined win-stay/lose-shift (WSLS) behaviour on the Iowa Gambling Task (IGT) in order to evaluate the influence of immediate rewards and losses in guiding real-world decision-making in patients with schizophrenia and major depressive disorder. Fifty-one patients with schizophrenia, 43 patients with major depressive disorder, and 51 healthy controls completed the IGT, as well as a series of clinical and cognitive measures. WSLS was assessed by quantifying trial-by-trial behaviour following rewards and losses on the IGT. Multivariate analyses of variance revealed that patients with schizophrenia demonstrated intact lose-shift behaviour, but significantly reduced win-stay rates compared to healthy controls. In contrast, no WSLS impairments emerged in the depressed group. Win-stay impairments in the schizophrenia group were significantly related to deficits in motivation and cognition. Patients with schizophrenia exhibit impaired reward-driven decision-making in the context of multiple choices with concurrent rewards and losses, and this appears to be driven by a reduced propensity for advantageous win-stay behaviour. With the importance of reward learning and decision-making in generating goal-directed behaviour, these findings suggest a potential mechanism contributing to the motivation deficits seen in schizophrenia.

Deciphering reward-based decision-making in schizophrenia: A meta-analysis and behavioral modeling of the Iowa Gambling Task

BACKGROUND

Patients with schizophrenia (SZP) have been reported to exhibit impairments in reward-based decision-making, but results are heterogeneous with multiple potential confounds such as age, intelligence level, clinical symptoms or medication, making it difficult to evaluate the robustness of these impairments.

METHODS

We conducted a meta-analysis of studies comparing the performance of SZP and healthy controls (HC) in the Iowa Gambling Task (IGT) as well as comprehensive analyses based on subject-level data (n = 303 SZP, n = 188 HC) to investigate reward-based decision-making in SZP. To quantify differences in the influence of individual deck features (immediate gain, gain frequency, net loss) between SZP and HC, we additionally employed a least-squares model.

RESULTS

SZP showed statistically significant suboptimal decisions as indicated by disadvantageous deck choices (d from 0.51 to −0.62) and lower net scores (d from −0.35 to −1.03) in a meta-analysis of k = 29 samples (n = 1127 SZP, n = 1149 HC) and these results were confirmed in a complementary subject-level analysis. Moreover, decision-making in SZP was characterized by a relative overweighting of immediate gain and net losses and an underweighting of gain frequency. Moderator analyses revealed that in part, decision-making in the IGT was moderated by intelligence level, medication and general symptom scores.

CONCLUSION

Our results indicate robust impairments in reward-based decision-making in SZP and suggest that decreased cognitive resources, such as working memory, may contribute to these alterations.

Is the Clinical Version of the Iowa Gambling Task Relevant for Assessing Choice Behavior in Cases of Internet Addiction?

Objective: A critical issue in research related to the Iowa gambling task (IGT) is the use of the alternative factors expected value and gain-loss frequency to distinguish between clinical cases and control groups. When the IGT has been used to examine cases of Internet addiction (IA), the literature reveals inconsistencies in the results. However, few studies have utilized the clinical version of IGT (cIGT) to examine IA cases. The present study aims to resolve previous inconsistencies and to examine the validity of the cIGT by comparing performances of controls with cases of Internet gaming disorder (IGD), a subtype of IA defined by the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders. Methods: The study recruited 23 participants with clinically diagnosed IGD and 38 age-matched control participants. Based on the basic assumptions of IGT and the gain-loss frequency viewpoint, a dependent variables analysis was carried out. Results: The results showed no statistical difference between the two groups in most performance indices and therefore support the findings of most IGT-IA studies; in particular, expected value and gain-loss frequency did not distinguish between the IGD cases and controls. However, the participants in both groups were influenced by the gain-loss frequency, revealing the existence of the prominent deck B phenomenon. Conclusion: The findings provide two possible interpretations. The first is that choice behavior deficits do not constitute a characteristic feature of individuals who have been diagnosed with IGD/IA. The second is that, as the cIGT was unable to distinguish the choice behavior of the IGD/IA participants from that of controls, the cIGT may not be relevant for assessing IGD based on the indices provided by the expected value and gain-loss frequency perspectives in the standard administration of IGT.

Anhedonia in depression and schizophrenia: A transdiagnostic challenge

BACKGROUND

Anhedonia, as a dysregulation of the reward circuit, is present in both Major Depressive Disorder (MDD) and schizophrenia (SZ).

AIMS

To elucidate the clinical and neurobiological differences between schizophrenia (SZ) and depression (MDD) in regard to anhedonia, while reconciling the challenges and benefits of assessing anhedonia as a transdiagnostic feature under the Research Domain Criteria (RDoC) framework.

METHODS

In this review, we summarize data from publications examining anhedonia or its underlying reward deficits in SZ and MDD. A literature search was conducted in OVID Medline, PsycINFO and EMBASE databases between 2000 and 2017.

RESULTS

While certain subgroups share commonalities, there are also important differences. SZ may be characterized by a disorganization, rather than a deficiency, in reward processing and cognitive function, including inappropriate energy expenditure and focus on irrelevant cues. In contrast, MDD has been characterized by deficits in anticipatory pleasure, development of reward associations, and integration of information from past experience. Understanding the roles of neurotransmitters and aberrant brain circuitry is necessary to appreciate differences in reward function in SZ and MDD.

CONCLUSION

Anhedonia as a clinical presentation of reward circuit dysregulation is an important and relatively undertreated symptom of both SZ and MDD. In order to improve patient outcomes and quality of life, it is important to consider how anhedonia fits into both diagnoses.

Risky decision-making under risk in schizophrenia: A deliberate choice?

BACKGROUND AND OBJECTIVES

Patients with schizophrenia reveal impaired decision-making strategies causing social, financial and health care problems. The extent to which deficits in decision-making reflect intentional risky choices in schizophrenia is still under debate. Based on previous studies we expected patients with schizophrenia to reveal a riskier performance on the GDT and to make more disadvantageous decisions on the IGT.

METHODS

In the present study, we investigated 38 patients with schizophrenia and 38 matched healthy control subjects with two competing paradigms regarding feedback: (1) The Game of Dice Task (GDT), in which the probabilities of winning or losing are stable and explicitly disclosed to the subject, to assess decision-making under risk and (2) the Iowa Gambling Task (IGT), which requires subjects to infer the probabilities of winning or losing from feedback, to investigate decision-making under ambiguity.

RESULTS

Patients with schizophrenia revealed an overall riskier performance on the GDT; although they adjusted their strategy over the course of the GDT, they still made significantly more disadvantageous choices than controls. More positive symptoms in patients with schizophrenia indicated by higher PANSS positive scores were associated with riskier choices and less use of negative feedback. Compared to healthy controls, they were not impaired in net score but chose more disadvantageous cards than controls on the first block of the IGT.

LIMITATIONS

Effects of medication at the time of testing cannot be ruled out.

CONCLUSIONS

Our findings suggest that patients with schizophrenia make riskier decisions and are less able to regulate their decision-making to implement advantageous strategies, even when the probabilities of winning or losing are explicitly disclosed. The dissociation between performance on the GDT and IGT suggests a pronounced impairment of executive functions related to the dorsolateral prefrontal cortex.

Steeper discounting of delayed rewards in schizophrenia but not first-degree relatives

Excessive discounting of future rewards has been related to a variety of risky behaviors and adverse clinical conditions. Prior work examining delay discounting in schizophrenia suggests an elevated discount rate. However, it remains uncertain whether this reflects the disease process itself or an underlying genetic vulnerability, whether it is selective for delay discounting or reflects pervasive changes in decision-making, and whether it is driven by specific clinical dimensions such as cognitive impairment. Here we investigated delay discounting, as well as loss aversion and risk aversion, in three groups: schizophrenia (SZ), unaffected first-degree family members (FM), and controls without a family history of psychosis (NC). SZ had elevated discounting, without changes in loss aversion or risk aversion. Contrary to expectations, the FM group did not show an intermediate phenotype in discounting. Higher discount rates correlated with lower cognitive performance on verbal reasoning, but this did not explain elevated discount rates in SZ. Group differences were driven primarily by the non-smoking majority of the sample. This study provides further evidence for elevated discounting in schizophrenia, and demonstrates that steeper discounting is not necessarily associated with familial risk, cannot be wholly accounted for by cognitive deficits, and is not attributable to smoking-related impulsivity.

A Simplified Model of Choice Behavior under Uncertainty

The Iowa Gambling Task (IGT) has been standardized as a clinical assessment tool (Bechara, 2007). Nonetheless, numerous research groups have attempted to modify IGT models to optimize parameters for predicting the choice behavior of normal controls and patients. A decade ago, most researchers considered the expected utility (EU) model (Busemeyer and Stout, 2002) to be the optimal model for predicting choice behavior under uncertainty. However, in recent years, studies have demonstrated that models with the prospect utility (PU) function are more effective than the EU models in the IGT (Ahn et al., 2008). Nevertheless, after some preliminary tests based on our behavioral dataset and modeling, it was determined that the Ahn et al. (2008) PU model is not optimal due to some incompatible results. This study aims to modify the Ahn et al. (2008) PU model to a simplified model and used the IGT performance of 145 subjects as the benchmark data for comparison. In our simplified PU model, the best goodness-of-fit was found mostly as the value of α approached zero. More specifically, we retested the key parameters α, λ, and A in the PU model. Notably, the influence of the parameters α, λ, and A has a hierarchical power structure in terms of manipulating the goodness-of-fit in the PU model. Additionally, we found that the parameters λ and A may be ineffective when the parameter α is close to zero in the PU model. The present simplified model demonstrated that decision makers mostly adopted the strategy of gain-stay loss-shift rather than foreseeing the long-term outcome. However, there are other behavioral variables that are not well revealed under these dynamic-uncertainty situations. Therefore, the optimal behavioral models may not have been found yet. In short, the best model for predicting choice behavior under dynamic-uncertainty situations should be further evaluated.

The neural underpinnings of cognitive flexibility and their disruption in psychotic illness

Schizophrenia (SZ) has long been associated with a variety of cognitive deficits, including reduced cognitive flexibility. More recent findings, however, point to tremendous inter-individual variability among patients on measures of cognitive flexibility/set-shifting. With an eye toward shedding light on potential sources of variability in set-shifting abilities among SZ patients, I examine the neural substrates of underlying probabilistic reversal learning (PRL) - a paradigmatic measure of cognitive flexibility - as well as neuromodulatory influences upon these systems. Finally, I report on behavioral and neuroimaging studies of PRL in SZ patients, discussing the potentially influences of illness profile and antipsychotic medications on cognitive flexibility in SZ.

Disadvantageous Deck Selection in the Iowa Gambling Task: The Effect of Cognitive Load

Research has shown that cognitive load affects overall Iowa Gambling Task (IGT) performance, but it is unknown whether such load impacts the selection of the individual decks that correspond to gains or losses. Here, participants performed the IGT either in a full attention condition or while engaged in a number monitoring task to divide attention. Results showed that the full attention group was more aware of the magnitude of gains or losses for each draw (i.e., payoff awareness) than was the divided attention group. However, the divided attention group was more sensitive to the frequency of the losses (i.e., frequency awareness), as evidenced by their increased preference for Deck B, which is the large but infrequent loss deck. An analysis across blocks showed that the number monitoring group was consistently more aware of loss frequency, whereas the full attention group shifted between awareness of loss frequency and awareness of payoff amount. Furthermore, the full attention group was better able to weigh loss frequency and payoff amount when making deck selections. These findings support the notion that diminished cognitive resources may result in greater selection of Deck B, otherwise known as the prominent Deck B phenomenon.

Decision making in healthy participants on the Iowa Gambling Task: new insights from an operant approach

The Iowa Gambling Task (IGT) has contributed greatly to the study of affective decision making. However, researchers have observed high inter-study and inter-individual variability in IGT performance in healthy participants, and many are classified as impaired using standard criteria. Additionally, while decision-making deficits are often attributed to atypical sensitivity to reward and/or punishment, the IGT lacks an integrated sensitivity measure. Adopting an operant perspective, two experiments were conducted to explore these issues. In Experiment 1, 50 healthy participants completed a 200-trial version of the IGT which otherwise closely emulated Bechara et al.'s (1999) original computer task. Group data for Trials 1–100 closely replicated Bechara et al.'s original findings of high net scores and preferences for advantageous decks, suggesting that implementations that depart significantly from Bechara's standard IGT contribute to inter-study variability. During Trials 101–200, mean net scores improved significantly and the percentage of participants meeting the “impaired” criterion was halved. An operant-style stability criterion applied to individual data revealed this was likely related to individual differences in learning rate. Experiment 2 used a novel operant card task—the Auckland Card Task (ACT)—to derive quantitative estimates of sensitivity using the generalized matching law. Relative to individuals who mastered the IGT, persistent poor performers on the IGT exhibited significantly lower sensitivity to magnitudes (but not frequencies) of rewards and punishers on the ACT. Overall, our findings demonstrate the utility of operant-style analysis of IGT data and the potential of applying operant concurrent-schedule procedures to the study of human decision making.

Deficits in emotion based decision-making in schizophrenia; a new insight based on the Iowa Gambling Task

BACKGROUND

Defective decision-making is a symptom of impaired cognitive function observed in patients with schizophrenia. Impairment on the Iowa Gambling Task (IGT) has been reported in patients with schizophrenia, but these results are inconsistent among studies.

METHODS

We differentiated subjects based on whether they expressed certainty at having deciphered an advantageous strategy in the course of the task. We investigated this impairment using the IGT in patients with schizophrenia and performed analysis different to standard advantageous decks minus disadvantageous decks in all 100 card choices, [C+D]-[A+B](1-100). We examined the effects on behavior after receiving a big penalty.

RESULTS

Results were dependent on participants utilizing with or without certainty, the best strategy for positive gain. Schizophrenic patients without certainty failed to show card choice shift, from disadvantageous to advantageous decks. Differences in card choices on the IGT were clearly shown between patients with schizophrenia and normal controls by the use of improvement from block 1 to blocks 3-5, [C+D]-[A+B]([41-100]-[1-20]) (P<0.001), rather than by the composite value of blocks 3-5, [C+D]-[A+B](41-100) (P=0.011). The deficit of emotion-based learning in schizophrenia without uncertainty were related to scores on the SANS and S5 attention. In addition, S1 affective flattering and S4 anhedonia-asociality were also related to these deficits. For a while, normal controls showed a smooth shift from disadvantageous to advantageous decks after big penalties, with or without a certainty for strategy. However, patients with schizophrenia failed to show switching from disadvantageous to advantageous decks, even after big penalties, under the same conditions.

CONCLUSIONS

Our results highlight certainty of strategy and behavior after a big penalty, as two points of difference between patients with schizophrenia and normal controls in the accumulation of net scores.

Motivational Deficits in Schizophrenia and the Representation of Expected Value

Motivational deficits (avolition and anhedonia) have historically been considered important negative symptoms of schizophrenia (SZ). Numerous studies have attempted to identify the neural substrates of avolition and anhedonia in schizophrenia , but these studies have not produced much agreement. Deficits in various aspects of reinforcement processing have been observed in individuals with schizophrenia, but it is not exactly clear which of these deficits actually engender motivational impairments in SZ. The purpose of this chapter is to examine how various reinforcement-related behavioral and neural signals could contribute to motivational impairments in both schizophrenia and psychiatric illness, in general. In particular, we describe different aspects of the concept of expected value (EV), such as the distinction between the EV of stimuli and the expected value of actions, the acquisition of value versus the estimation of value, and the discounting of value as a consequence of time or effort required. We conclude that avolition and anhedonia in SZ are most commonly tied to aberrant signals for expected value, in the context of learning. We discuss implications for further research on the neural substrates of motivational impairments in psychiatric illness.

Mechanisms Underlying Motivational Deficits in Psychopathology: Similarities and Differences in Depression and Schizophrenia

Motivational and hedonic impairments are core aspects of a variety of types of psychopathology. These impairments cut across diagnostic categories and may be critical to understanding major aspects of the functional impairments accompanying psychopathology. Given the centrality of motivational and hedonic systems to psychopathology, the Research Domain Criteria (RDoC) initiative includes a "positive valence" systems domain that outlines a number of constructs that may be key to understanding the nature and mechanisms of motivational and hedonic impairments in psychopathology. These component constructs include initial responsiveness to reward, reward anticipation or expectancy, incentive or reinforcement learning, effort valuation, and action selection. Here, we review behavioral and neuroimaging studies providing evidence for impairments in these constructs in individuals with psychosis versus in individuals with depressive pathology. There are important differences in the nature of reward-related and hedonic deficits associated with psychosis versus depression that have major implications for our understanding of etiology and treatment development. In particular, the literature strongly suggests the presence of impairments in in-the-moment hedonics or "liking" in individuals with depressive pathology, particularly among those who experience anhedonia. Such deficits may propagate forward and contribute to impairments in other constructs that are dependent on hedonic responses, such as anticipation, learning, effort, and action selection. Such hedonic impairments could reflect alterations in dopamine and/or opioid signaling in the striatum related to depression or specifically to anhedonia in depressed populations. In contrast, the literature points to relatively intact in-the-moment hedonic processing in psychosis, but provides much evidence for impairments in other components involved in translating reward to action selection. Particularly, individuals with schizophrenia exhibit altered reward prediction and associated striatal and prefrontal activation, impaired reward learning, and impaired reward-modulated action selection.

Integrating frequency and magnitude information in decision-making in schizophrenia: An account of patient performance on the Iowa Gambling Task

BACKGROUND

The Iowa Gambling Task (IGT; Bechara et al., 1994) has frequently been used to assess risky decision making in clinical populations, including patients with schizophrenia (SZ). Poor performance on the IGT is often attributed to reduced sensitivity to punishment, which contrasts with recent findings from reinforcement learning studies in schizophrenia.

METHODS

In order to investigate possible sources of IGT performance deficits in SZ patients, we combined data from the IGT from 59 SZ patients and 43 demographically-matched controls with data from the Balloon Analog Risk Task (BART) in the same participants. Our analyses sought to specifically uncover the role of punishment sensitivity and delineate the capacity to integrate frequency and magnitude information in decision-making under risk.

RESULTS

Although SZ patients, on average, made more choices from disadvantageous decks than controls did on the IGT, they avoided decks with frequent punishments at a rate similar to controls. Patients also exhibited excessive loss-avoidance behavior on the BART.

CONCLUSIONS

We argue that, rather than stemming from reduced sensitivity to negative consequences, performance deficits on the IGT in SZ patients are more likely the result of a reinforcement learning deficit, specifically involving the integration of frequencies and magnitudes of rewards and punishments in the trial-by-trial estimation of expected value.

Relationships between brain-derived neurotrophic factor, clinical symptoms, and decision-making in chronic schizophrenia: data from the Iowa Gambling Task

The levels of brain-derived neurotrophic factor (BDNF) are significantly decreased in patients with schizophrenia and correlate with impairments in cognitive function. However, no study has investigated the relationship between the serum BDNF levels and decision-making. We compared patients with schizophrenia to healthy controls with respect to their decision-making ability and serum BDNF levels. Eighty-six chronic schizophrenia patients and 51 healthy controls participated in this study. We controlled for gender, age, and estimated intelligence quotient (IQ), and we investigated the differences in decision-making performance on the Iowa Gambling Task (IGT) between the schizophrenia patient and control groups. We also compared the IGT scores, the serum BDNF levels, and the clinical symptoms between the groups. The IGT scores of the schizophrenia patients were lower than those of the controls. A negative correlation was detected between the mean net scores on the trials in the final two blocks and the serum BDNF levels (p < 0.05). Multiple regression analysis revealed that depressive symptoms and the serum BDNF levels were significantly associated with the mean net scores on the trials in the final two blocks. Based on these results, impaired sensitivity to both reward and punishment is associated with depressive symptoms and reduced serum BDNF levels in chronic schizophrenia patients and may be related to their poor performance on the IGT.

Are normal decision-makers sensitive to changes in value contrast under uncertainty? Evidence from the Iowa Gambling Task

The Iowa Gambling Task (IGT) developed by Bechara et al. in 1994 is used to diagnose patients with Ventromedial Medial Prefrontal Cortex (VMPFC) lesions, and it has become a landmark in research on decision making. According to Bechara et al., the manipulation of progressive increments of monetary value can normalize the performance of patients with VMPFC lesions; thus, they developed a computerized version of the IGT. However, the empirical results showed that patients' performances did not improve as a result of this manipulation, which suggested that patients with VMPFC lesions performed myopically for future consequences. Using the original version of the IGT, some IGT studies have demonstrated that increments of monetary value significantly influence the performance of normal subjects in the IGT. However, other research has resulted in inconsistent findings. In this study, we used the computerized IGT (1X-IGT) and manipulated the value contrast of progressive increments (i.e., by designing the 10X-IGT, which contained 10 times of progressive increment) to investigate the influence of value contrast on the performance of normal subjects. The resulting empirical observations indicated that the value contrast (1X- vs. 10X-IGT) of the progressive increment had no effect on the performance of normal subjects. This study also provides a discussion of the issue of value in IGT-related studies. Moreover, we found the “prominent deck B phenomenon” in both versions of the IGT, which indicated that the normal subjects were guided mostly by the gain-loss frequency, rather than by the monetary value contrast. In sum, the behavioral performance of normal subjects demonstrated a low correlation with changes in monetary value, even in the 10X-IGT.

The motivation and pleasure dimension of negative symptoms: neural substrates and behavioral outputs

A range of emotional and motivation impairments have long been clinically documented in people with schizophrenia, and there has been a resurgence of interest in understanding the psychological and neural mechanisms of the so-called "negative symptoms" in schizophrenia, given their lack of treatment responsiveness and their role in constraining function and life satisfaction in this illness. Negative symptoms comprise two domains, with the first covering diminished motivation and pleasure across a range of life domains and the second covering diminished verbal and non-verbal expression and communicative output. In this review, we focus on four aspects of the motivation/pleasure domain, providing a brief review of the behavioral and neural underpinnings of this domain. First, we cover liking or in-the-moment pleasure: immediate responses to pleasurable stimuli. Second, we cover anticipatory pleasure or wanting, which involves prediction of a forthcoming enjoyable outcome (reward) and feeling pleasure in anticipation of that outcome. Third, we address motivation, which comprises effort computation, which involves figuring out how much effort is needed to achieve a desired outcome, planning, and behavioral response. Finally, we cover the maintenance emotional states and behavioral responses. Throughout, we consider the behavioral manifestations and brain representations of these four aspects of motivation/pleasure deficits in schizophrenia. We conclude with directions for future research as well as implications for treatment.

Physical comorbidity and its relevance on mortality in schizophrenia: a naturalistic 12-year follow-up in general hospital admissions

Schizophrenia is a major psychotic disorder with significant comorbidity and mortality. Patients with schizophrenia are said to suffer more type-2 diabetes mellitus (T2DM) and diabetogenic complications. However, there is little consistent evidence that comorbidity with physical diseases leads to excess mortality in schizophrenic patients. Consequently, we investigated whether the burden of physical comorbidity and its relevance on hospital mortality differed between patients with and without schizophrenia in a 12-year follow-up in general hospital admissions. During 1 January 2000 and 31 June 2012, 1418 adult patients with schizophrenia were admitted to three General Manchester NHS Hospitals. All comorbid diseases with a prevalemce ≥1% were compared with those of 14,180 age- and gender-matched hospital controls. Risk factors, i.e. comorbid diseases that were predictors for general hospital mortality were identified using multivariate logistic regression analyses. Compared with controls, schizophrenic patients had a higher proportion of emergency admissions (69.8 vs. 43.0%), an extended average length of stay at index hospitalization (8.1 vs. 3.4 days), a higher number of hospital admissions (11.5 vs. 6.3), a shorter length of survival (1895 vs. 2161 days), and a nearly twofold increased mortality rate (18.0 vs. 9.7%). Schizophrenic patients suffered more depression, T2DM, alcohol abuse, asthma, COPD, and twenty-three more diseases, many of them diabetic-related complications or other environmentally influenced conditions. In contrast, hypertension, cataract, angina, and hyperlipidaemia were less prevalent in the schizophrenia population compared to the control population. In deceased schizophrenic patients, T2DM was the most frequently recorded comorbidity, contributing to 31.4% of hospital deaths (only 14.4% of schizophrenic patients with comorbid T2DM survived the study period). Further predictors of general hospital mortality in schizophrenia were found to be alcoholic liver disease (OR = 10.3), parkinsonism (OR = 5.0), T1DM (OR = 3.8), non-specific renal failure (OR = 3.5), ischaemic stroke (OR = 3.3), pneumonia (OR = 3.0), iron-deficiency anaemia (OR = 2.8), COPD (OR = 2.8), and bronchitis (OR = 2.6). There were no significant differences in their impact on hospital mortality compared to control subjects with the same diseases except parkinsonism which was associated with higher mortality in the schizophrenia population compared with the control population. The prevalence of parkinsonism was significantly elevated in the 255 deceased schizophrenic patients (5.5 %) than in those 1,163 surviving the study period (0.8 %, OR = 5.0) and deceased schizophrenic patients had significantly more suffered extrapyramidal symptoms than deceased control subjects (5.5 vs. 1.5 %). Therefore patients with schizophrenia have a higher burden of physical comorbidity that is associated with a worse outcome in a 12-year follow-up of mortality in general hospitals compared with hospital controls. However, schizophrenic patients die of the same physical diseases as their peers without schizophrenia. The most relevant physical risk factors of general hospital mortality are T2DM, COPD and infectious respiratory complications, iron-deficiency anaemia, T1DM, unspecific renal failure, ischaemic stroke, and alcoholic liver disease. Additionally, parkinsonism is a major risk factor for general hospital mortality in schizophrenia. Thus, optimal monitoring and management of acute T2DM and COPD with its infectious respiratory complications, as well as the accurate detection and management of iron-deficiency anaemia, of diabetic-related long-term micro- and macrovascular complications, of alcoholic liver disease, and of extrapyramidal symptoms are of utmost relevance in schizophrenia.

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.

Dual conception of risk in the Iowa Gambling Task: effects of sleep deprivation and test-retest gap

Risk in the Iowa Gambling Task (IGT) is often understood in terms of intertemporal choices, i.e., preference for immediate outcomes in favor of delayed outcomes is considered risky decision making. According to behavioral economics, healthy decision makers are expected to refrain from choosing the short-sighted immediate gain because, over time (10 trials of the IGT), the immediate gains result in a long term loss (net loss). Instead decision makers are expected to maximize their gains by choosing options that, over time (10 trials), result in delayed or long term gains (net gain). However, task choices are sometimes made on the basis of the frequency of reward and punishment such that frequent rewards/infrequent punishments are favored over infrequent rewards/frequent punishments. The presence of these two attributes (intertemporality and frequency of reward) in IGT decision making may correspond to the emotion-cognition dichotomy and reflect a dual conception of risk. Decision making on the basis of the two attributes was tested under two conditions: delay in retest and sleep deprivation. An interaction between sleep deprivation and time delay was expected to attenuate the difference between the two attributes. Participants were 40 male university students. Analysis of the effects of IGT attribute type (intertemporal vs. frequency of reinforcement), sleep deprivation (sleep deprivation vs. no sleep deprivation), and test-retest gap (short vs. long delay) showed a significant within-subjects effect of IGT attribute type thus confirming the difference between the two attributes. Sleep deprivation had no effect on the attributes, but test-retest gap and the three-way interaction between attribute type, test-retest gap, and sleep deprivation were significantly different. Post-hoc tests revealed that sleep deprivation and short test-retest gap attenuated the difference between the two attributes. Furthermore, the results showed an expected trend of increase in intertemporal decision making at retest suggesting that intertemporal decision making benefited from repeated task exposure. The present findings add to understanding of the emotion-cognition dichotomy. Further, they show an important time-dependent effect of a universally experienced constraint (sleep deprivation) on decision making. It is concluded that risky decision making in the IGT is contingent on the attribute under consideration and is affected by factors such as time elapsed and constraint experienced before the retest.

O Iowa Gambling Task: uma revisão crítica

O Iowa Gambling Task (IGT) é uma tarefa amplamente utilizada na avaliação da capacidade de tomada de decisão. Neste artigo, procede-se à revisão da literatura, comparando-se as versões do IGT, as diferentes medidas de avaliação do desempenho e as alterações introduzidas nos procedimentos, nomeadamente no feedback, na aleatorização espacial dos baralhos, no número de ensaios e de cartas por baralho, nas instruções, na remuneração e na manipulação das recompensas e punições. Desta análise, conclui-se que as diversas versões da tarefa, as alterações nos procedimentos de aplicação e as diferentes medidas utilizadas na avaliação têm impacto no desempenho, prejudicam a comparação entre estudos e as generalizações dos resultados. Finalmente, apresentam-se sugestões para uma maior adequação dos procedimentos.

Reexamining the validity and reliability of the clinical version of the iowa gambling task: evidence from a normal subject group

Over past decade, the Iowa gambling task (IGT) has been utilized to test various decision deficits induced by neurological damage or psychiatric disorders. The IGT has recently been standardized for identifying 13 different neuropsychological disorders. Neuropsychological patients choose bad decks frequently, and normal subjects prefer good expected value (EV) decks. However, the IGT has several validity and reliability problems. Some research groups have pointed out that the validity of IGT is influenced by the personality and emotional state of subjects. Additionally, several other studies have proposed that the “prominent deck B phenomenon” (PDB phenomenon) – that is, normal subjects preferring bad deck B – may be the most serious problem confronting IGT validity. Specifically, deck B offers a high frequency of gains but negative EV. In the standard IGT administration, choice behavior can be understood with reference to gain-loss frequency (GLF) rather than inferred future consequences (EV, the basic assumption of IGT). Furthermore, using two different criteria (basic assumption vs. professional norm) results in significantly different classification results. Therefore, we recruited 72 normal subjects to test the validity and reliability of IGT. Each subject performed three runs of the computer-based clinical IGT version. The PDB phenomenon has been observed to a significant degree in the first and second stages of the clinical IGT version. Obviously, validity, reliability, and the practice effect were unstable between two given stages. The present form of the clinical IGT version has only one stage, so its use should be reconsidered for examining normal decision makers; results from patient groups must also be interpreted with great care. GLF could be the main factor to be considered in establishing the constructional validity and reliability of the clinical IGT version.

A further evaluation of decision-making under risk and under ambiguity in schizophrenia

Abnormal decision-making has been described as a key-concept to understand some behavioral disturbances in schizophrenia. However, whether schizophrenia patients display impairments in profitable decision-making on experimental designs is still controversial (1) to assess performance on decision-making paradigms under ambiguity and under risk conditions in a large sample of schizophrenia patients and (2) to study the impact of clinical variables on decision-making performance in schizophrenia. The Iowa gambling task (IGT) and the game of dice task (GDT) were administered to assess, respectively, decision-making under ambiguity and under risk in 63 schizophrenia patients and 67 healthy controls. In addition, clinical variables (e.g., schizophrenic symptoms, self-reported depression, and impulsivity) were evaluated using appropriate questionnaires the same day. Pharmacological treatments were reported. Schizophrenia patients had impaired performances on both IGT and GDT tasks. No correlation between the decision-making tasks performance and clinical variables was found. Lower gains on the GDT were associated with executive dysfunctioning in schizophrenia. These findings give evidence that schizophrenia patients display impairments in both decision-making under ambiguity and under risk.

Money for nothing - Atrophy correlates of gambling decision making in behavioural variant frontotemporal dementia and Alzheimer's disease

Neurodegenerative patients show often severe everyday decision making problems. Currently it is however not clear which brain atrophy regions are implicated in such decision making problems. We investigated the atrophy correlates of gambling decision making in a sample of 63 participants, including two neurodegenerative conditions (behavioural variant frontotemporal dementia — bvFTD; Alzheimer's disease — AD) as well as healthy age-matched controls. All participants were tested on the Iowa Gambling Task (IGT) and the behavioural IGT results were covaried against the T1 MRI scans of all participants to identify brain atrophy regions implicated in gambling decision making deficits. Our results showed a large variability in IGT performance for all groups with both patient groups performing especially poor on the task. Importantly, bvFTD and AD groups did not differ significantly on the behavioural performance of the IGT. However, by contrast, the atrophy gambling decision making correlates differed between bvFTD and AD, with bvFTD showing more frontal atrophy and AD showing more parietal and temporal atrophy being implicated in decision making deficits, indicating that both patient groups fail the task on different levels. Frontal (frontopolar, anterior cingulate) and parietal (retrosplenial) cortex atrophy covaried with poor performance on the IGT. Taken together, the atrophy correlates of gambling decision making show that such deficits can occur due to a failure of different neural structures, which will inform future diagnostics and treatment options to alleviate these severe everyday problems in neurodegenerative patients.

Mirrored prominent deck B phenomenon: frequent small losses override infrequent large gains in the inverted Iowa Gambling Task

Since Bechara et al. pioneered its development, the Iowa Gambling Task (IGT) has been widely applied to elucidate decision behavior and medial prefrontal function. Although most decision makers can hunch the final benefits of IGT, ventromedial prefrontal lesions generate a myopic choice pattern. Additionally, the Iowa group developed a revised IGT (inverted IGT, iIGT) to confirm the IGT validity. Each iIGT trial was generated from the trial of IGT by multiplying by a "-" to create an inverted monetary value. Thus, bad decks A and B in the IGT become good decks iA and iB in the iIGT; additionally, good decks C and D in the IGT become bad decks iC and iD in the iIGT. Furthermore, IGT possessed mostly the gain trials, and iIGT possessed mainly the loss trials. Therefore, IGT is a frequent-gain-based task, and iIGT is a frequent-loss-based task. However, a growing number of IGT-related studies have identified confounding factors in IGT (i.e., gain-loss frequency), which are demonstrated by the prominent deck B phenomenon (PDB phenomenon). Nevertheless, the mirrored PDB phenomenon and guiding power of gain-loss frequency in iIGT have seldom been reexamined. This experimental finding supports the prediction based on gain-loss frequency. This study identifies the mirrored PDB phenomenon. Frequent small losses override occasional large gains in deck iB of the iIGT. Learning curve analysis generally supports the phenomenon based on gain-loss frequency rather than final outcome. In terms of iIGT and simple versions of iIGT, results of this study demonstrate that high-frequency loss, rather than a satisfactory final outcome, dominates the preference of normal decision makers under uncertainty. Furthermore, normal subjects prefer "no immediate punishment" rather than "final reward" under uncertainty.

[Decision-making and schizophrenia]

Abnormalities involving the prefrontal cortex (PFC) have long been postulated to underpin the pathophysiology of schizophrenia. Investigations of PFC integrity have focused mainly on the dorsolateral PFC (DLPFC) and abnormalities in this region have been extensively documented. However, defects in schizophrenia may extend to other prefrontal regions, including the ventromedial PFC (VMPFC), and evidence of VMPFC abnormalities comes from neuropathological, structural and functional studies. Patients with acquired brain injury to the VMPFC display profound disruption of social behaviour and poor judgment in their personal lives. The Iowa Gambling Task (IGT) was developed to assess decision-making in these neurological cases : it presents a series of 100 choices from four card decks that differ in the distribution of rewarding and punishing outcomes. Whilst healthy volunteers gradually develop a preference for the two "safe" decks over the course of the task, patients with VMPFC lesions maintain a preference for the two "risky" decks which are associated with high reinforcement in the short term, but significant long-term debt. Interestingly, damage to VMPFC may cause both poor performance on the IGT and lack of insight concerning the acquired personality modification. Recently, our group reported a trait-related decisionmaking impairment in the three phases of bipolar disorder. In a PET study, VMPFC dysfunction was shown in bipolar manic patients impaired on a decision-making task and an association between decision-making cognition and lack of insight was described in mania. A quantitative association between grey matter volume of VMPFC and memory impairment was previously reported in schizophrenia. Research suggests that lack of insight is a prevalent feature in schizophrenia patients, like auditory hallucinations, paranoid or bizarre delusions, and disorganized speech and thinking. Because schizophrenia is associated with significant social or occupational dysfunction, previous research assessed decision-making function but indicates conflicting results. Thirteen studies have reported impaired IGT performance in patients with schizophrenia and, in seven reports, no significant differences in IGT performance between patient and healthy control groups were found. Those discrepancies may relate to multiple factors. First, most of the studies included small sample size and negative findings may be due to the large variance of net scores. Second, as suggested by Rodríguez-Sánchez et al., there is a wide disparity in performance by control subjects across studies. Third, intelligence quotient (IQ) score and level of education may be correlated with IGT performance, which may explain IGT performance differences in studies that did not control for educational or IQ score. Fourth, only two studies have systematically controlled for substance use disorder, a potential confounder. Fifth, only two studies assessed the impact of antipsychotic (AP) class on performance. Sixth, to our knowledge, no study assessed the impact of AP dosage on decision-making ability, while AP dose-reduction and dopamine increase, might lead to improvements, in cognitive functions in schizophrenia and in IGT performance in bipolar disorder, respectively. Finally, discrepancies between studies may be related to the heterogeneity of diagnostic groups. Two of the negative studies included schizophrenia and schizoaffective disorder while positive studies have generally included only patients with schizophrenia. Nevertheless, some studies that included only patients with schizophrenia failed to find differences between groups. Thus, further research should assess decision-making in schizophrenia by testing a large group of patients with homogeneity of diagnostic, in comparison with a large group of control subjects. Authors should control for IQ or level of education, substance use disorder and smoking status. While it is now accepted that DLPFC defects in schizophrenia may extend to VMPFC, future investigations should test for an association between memory, insight ability and IGT performance and assess the impact of antipsychotic dosage upon performance.

Iowa gambling task: there is more to consider than long-term outcome. Using a linear equation model to disentangle the impact of outcome and frequency of gains and losses

The Iowa Gambling Task (IGT) has been widely used to assess differences in decision-making under uncertainty. Recently, several studies have shown that healthy subjects do not meet the basic predictions of the task (i.e., prefer options with positive long-term outcome), hence questioning its basic assumptions. Since choice options are characterized by gain and net loss frequency in addition to long-term outcome, we hypothesized that a combination of features rather than a single feature would influence participants’ choices. Offering an alternative way of modeling IGT data, we propose to use a system of linear equations to estimate weights that quantify the influence of each individual feature on decision-making in the IGT. With our proposed model it is possible to disentangle and quantify the impact of each of these features. Results from 119 healthy young subjects suggest that choice behavior is predominantly influenced by gain and loss frequency. Subjects preferred choices associated with high-frequency gains to those with low-frequency gains, regardless of long-term outcome. However, among options with low-frequency gains, subjects learned to distinguish between choices that led to advantageous and disadvantageous long-term consequences. This is reflected in the relationship between the weights for gain frequency (highest), loss frequency (intermediate), and long-term outcome (lowest). Further, cluster analysis of estimated feature weights revealed sub-groups of participants with distinct weight patterns and associated advantageous decision behavior. However, subjects in general do not learn to solely base their preference for particular decks on expected long-term outcome. Consequently, long-term outcome alone is not able to drive choice behavior on the IGT. In sum, our model facilitates a more focused conclusion about the factors guiding decision-making in the IGT. In addition, differences between clinical groups can be assessed for each factor individually.

Schizophrenia and risk-taking: impaired reward but preserved punishment processing

Risky decision-making is subserved by the frontostriatal system, which includes a network of interconnected brain regions known to be dysfunctional in patients with schizophrenia. This study aimed to investigate whether and to what extent patients with schizophrenia display a different pattern of risk-taking behavior relative to matched healthy controls. The Balloon Analogue Risk Task (BART) and the Risky-Gains Task were used as naturalistic measures of risk-taking behavior in 25 patients with schizophrenia and 25 controls. Results of the BART revealed that patients behaved more conservatively, and this in turn led to suboptimal risky decision-making. Consistently, patients behaved more conservatively in the Risky-Gains Task. Interestingly, however, they adjusted the pattern of risk-taking following a punished trial similar to controls. These findings indicate that patients have impaired reward but preserved punishment processing. This study complements previous studies on decision-making in schizophrenia and suggests specific rather than widespread abnormalities along the frontostriatal system in schizophrenia.

Response dynamics: A new window on the decision process

The history of judgment and decision making is defined by a trend toward increasingly nuanced explanations of the decision making process. Recently, process models have become incredibly sophisticated, yet the tools available to directly test these models have not kept pace. These increasingly complex process models require increasingly complex process data by which they can be adequately tested. We propose a new class of data collection that will facilitate evaluation of sophisticated process models. Tracking mouse paths during a continuous response provides an implicit measure of the growth of preference that produces a choice—rather than the current practice of recording just the button press that indicates that choice itself. Recent research in cognitive science (Spivey & Dale, 2006) has shown that cognitive processing can be revealed in these dynamic motor responses. Unlike current process methodologies, these response dynamics studies can demonstrate continuous competition between choice options and even online preference reversals. Here, in order to demonstrate the mechanics and utility of the methodology, we present an example response dynamics experiment utilizing a common multi-alternative decision task.

Development of decision making: sequential versus integrative rules

Decisions can be made by applying a variety of decision-making rules-sequential rules in which decisions are based on a sequential evaluation of choice dimensions and the integrative normative rule in which decisions are based on an integration of choice dimensions. In this study, we investigated the developmental trajectory of such decision-making rules. In the Gambling Machine Task, participants choose between options that differ in three dimensions: frequency of loss, amount of loss, and certain gain. The task was administered to 231 children and adolescents (age range=8-17 years). Latent group analysis of their performance allowed precise classification of the underlying decision rules. The majority of participants used sequential decision rules, and the number of evaluated dimensions in these rules increased with age. Integrative rule use decreased with age. We discuss these results in light of traditional developmental theories and fuzzy trace theory.

Emotion-Based Decision Making in schizophrenia: evidence from the Iowa Gambling Task

The decision making can be defined as the mental process in which a “choice is made after reflecting on the consequences of that choice” (Bechara & Van Der Linden, 2005; Bechara et al., 1997). It is a complex process that involves cognitive as well as emotion-based functions. In fact human beings make fast adaptive decisions in daily life, and that is based on the skill to relate emotion to contextual stimuli in order to anticipate outcomes through activation of emotional states (Bechara et al., 2005). In this regard, the ventromedial prefrontal cortex (VMPFC) has been widely recognized to play a key role in the emotional decision making process. The VMPFC includes the medial part of the orbitofrontal cortex (OFC), the more ventral sectors of the medial prefrontal cortex and the anterior cingulate cortex (Bechara et al., 1997). In particular the OFC, within the VMPFC, is part of a neural system underpinning decision-making and reward-related behaviours which are thought to be linked to social conduct (Rolls, 2000).

Goal representations and motivational drive in schizophrenia: the role of prefrontal-striatal interactions

The past several years have seen a resurgence of interest in understanding the psychological and neural bases of what are often referred to as "negative symptoms" in schizophrenia. These aspects of schizophrenia include constructs such as asociality, avolition (a reduction in the motivation to initiate or persist in goal-directed behavior), and anhedonia (a reduction in the ability to experience pleasure). We believe that these dimensions of impairment in individuals with schizophrenia reflect difficulties using internal representations of emotional experiences, previous rewards, and motivational goals to drive current and future behavior in a way that would allow them to obtain desired outcomes, a deficit that has major clinical significance in terms of functional capacity. In this article, we review the major components of the systems that link experienced and anticipated rewards with motivated behavior that could potentially be impaired in schizophrenia. We conclude that the existing evidence suggests relatively intact hedonics in schizophrenia, but impairments in some aspects of reinforcement learning, reward prediction, and prediction error processing, consistent with an impairment in "wanting." As of yet, there is only indirect evidence of impairment in anterior cingulate and orbital frontal function that may support value and effort computations. However, there are intriguing hints that individuals with schizophrenia may not be able to use reward information to modulate cognitive control and dorsolateral prefrontal cortex function, suggesting a potentially important role for cortical-striatal interactions in mediating impairment in motivated and goal-directed behavior in schizophrenia.

Impaired decision making in schizophrenia and orbitofrontal cortex lesion patients

BACKGROUND

The aim of this study was to examine impaired decision making in patients with schizophrenia and in patients with orbitofrontal cortex lesions.

METHODS

Schizophrenia patients (N=21), healthy controls (N=20) and an independent group of orbitofrontal patients (N=10) underwent a computerized version of the "Regret Gambling Task". Participants chose between two gambles, each having different probabilities and different expected monetary outcomes, and rated their emotional states after seeing the obtained outcome. Regret was induced by providing information about the outcome of the unchosen gamble.

RESULTS

Healthy controls reported emotional responses consistent with counterfactual reasoning between obtained and unobtained outcomes; they chose minimizing future regret and were able to learn from their emotional experience. In contrast, orbitofrontal patients and schizophrenia patients with prominent positive symptoms did not report any regret and did not anticipate any negative consequences of their choices. Our results demonstrate first the presence of very different behavioural deficits within the spectrum of schizophrenia patients which may have contributed to the discrepancies observed in previous studies. Second, the results suggest that a subgroup of schizophrenia patients might have an orbitofrontal dysfunction, in fact, schizophrenia patients with positive symptoms have a behavioural dysfunction analogous to that of the orbitofrontal patients.

CONCLUSION

Schizophrenia patients with prominent positive symptoms were unable to integrate cognitive and emotional components of decision making which may contribute to their inability to generate adaptive behaviours in social and individual environments.

Prefer a cash slap in your face over credit for halva

We investigated how frequency and amount of punishment affect the decision making of Iranian subjects. In our first experiment, performing a computer-based Persian version of the Iowa Gambling Task (IGT), our subjects scored remarkably lower than their Western counterparts. Moreover, our subjects chose more frequently and more rapidly from decks that had less frequent but larger amounts of punishments in comparison to decks that had more frequent punishments with smaller amounts. In our second experiment, subjects did not differentiate between decks with the same frequency of punishment but with different punishment amounts. However, among decks with the same amount but different frequency of punishment, a significant preference was apparent towards decks with less frequency of punishment. Our results differ from previous studies, indicating a different strategy in risky decision making among healthy adult Iranian subjects, as they show low attention to the amount of punishment and are more concerned with the frequency of punishment.