The effects of reward and punishment contingencies on decision-making in multiple sclerosis

Metabolic costs of walking and arm reaching in persons with mild multiple sclerosis

Movement slowness is a common and disruptive symptom of multiple sclerosis (MS). A potential cause is that individuals with MS slow down to conserve energy as a behavioral adjustment to heightened metabolic costs of movement. To investigate this prospect, we measured the metabolic costs of both walking and seated arm reaching at five speeds in persons with mild MS (pwMS; n = 13; 46.0 ± 7.7 yr) and sex- and age-matched controls (HCs; n = 13; 45.8 ± 7.8 yr). Notably, the cohort of pwMS was highly mobile and no individuals required a cane or aid when walking. We found that the net metabolic power of walking was approximately 20% higher for pwMS across all speeds (P = 0.0185). In contrast, we found no differences in the gross power of reaching between pwMS and HCs (P = 0.492). Collectively, our results suggest that abnormal slowness of movement in MS-particularly reaching-is not the consequence of heightened effort costs and that other sensorimotor mechanisms are playing a considerable role in slowing.NEW & NOTEWORTHY Individuals with multiple sclerosis (MS) often move more slowly than those without the disease. A possible cause is that movements in MS are more energetically expensive and slowing is an adaptation to conserve metabolic resources. Here, we find that while walking is more costly for persons with MS, arm-reaching movements are not. These results bring into question the driving force of movement slowness in MS and implicate other motor-related networks contributing to slowing.

Kessler Foundation Strategy-Based Training to Enhance Memory (KF-STEM™): Study protocol for a single site double-blind randomized, clinical trial in Multiple Sclerosis

New learning and memory impairments are common in Multiple Sclerosis (MS) and negatively impact everyday life, including occupational and social functioning. Despite the demand for learning and memory treatments, few cognitive rehabilitation protocols are supported by Class I research evidence, limiting the degree to which effective treatments may be utilized with persons with MS. The present double-blind, placebo controlled randomized clinical trial (RCT) examines the efficacy of an 8-session cognitive rehabilitation protocol encompassing training in the application of three strategies with the strongest empirical evidence (self-generation, spaced learning and retrieval practice) to treat impaired learning and memory in persons with MS, Kessler Foundation Strategy-based Training to Enhance Memory (KF-STEM™). A sample of 120 participants with clinically definite MS who have impairments in new learning and memory will be enrolled. Outcomes will be assessed via three mechanisms, an Assessment of Global Functioning, which examines everyday functioning and quality of life, a Neuropsychological Evaluation to examine objective cognitive performance, and functional Magnetic Resonance Imaging to examine the impact of treatment on patterns of cerebral activation. We will additionally evaluate the longer-term efficacy of KF-STEM™ on everyday functioning and neuropsychological assessment through a 6-month follow-up evaluation and evaluate the impact of booster sessions in maintaining the treatment effect over time. The methodologically rigorous design of the current study will provide Class I evidence for the KF-STEM™ treatment protocol for persons with MS.

“I wanna live and not think about the future” what place for advance care planning for people living with severe multiple sclerosis and their families? A qualitative study

Background

Little is known about how people with multiple sclerosis (MS) and their families comprehend advance care planning (ACP) and its relevance in their lives.

Aim

To explore under what situations, with whom, how, and why do people with MS and their families engage in ACP.

Methods

We conducted a qualitative study comprising interviews with people living with MS and their families followed by an ethical discussion group with five health professionals representing specialties working with people affected by MS and their families. Twenty-seven people with MS and 17 family members were interviewed between June 2019 and March 2020. Interviews and the ethical discussion group were audio-recorded and transcribed verbatim. Data were analysed using the framework approach.

Results

Participants’ narratives focused on three major themes: (i) planning for an uncertain future; (ii) perceived obstacles to engaging in ACP that included uncertainty concerning MS disease progression, negative previous experiences of ACP discussions and prioritising symptom management over future planning; (iii) Preferences for engagement in ACP included a trusting relationship with a health professional and that information then be shared across services. Health professionals’ accounts from the ethical discussion group departed from viewing ACP as a formal document to that of an ongoing process of seeking preferences and values. They voiced similar concerns to people with MS about uncertainty and when to initiate ACP-related discussions. Some shared concerns of their lack of confidence when having these discussions.

Conclusion

These findings support the need for a whole system strategic approach where information about the potential benefits of ACP in all its forms can be shared with people with MS. Moreover, they highlight the need for health professionals to be skilled and trained in engaging in ACP discussions and where information is contemporaneously and seamlessly shared across services.

A realist review of advance care planning for people with multiple sclerosis and their families

Background

Advance care planning (ACP) is reported to improve the quality of outcomes of care among those with life-limiting conditions. However, uptake is low among people living with multiple sclerosis (MS) and little is known about why or how people with MS engage in this process of decision-making.

Aims

To develop and refine an initial theory on engagement in ACP for people with MS and to identify ways to improve its uptake for those who desire it.

Methods

Realist review following published protocol and reporting following Realist and Meta-narrative Evidence Synthesis: Evolving Standards (RAMESES) guidelines. A multi-disciplinary team searched MEDLINE, PsychInfo, CINAHL, Scopus, Web of Science, Embase, Google Scholar in addition to other sources from inception to August 2019. Quantitative or qualitative studies, case reports, and opinion or discussion articles related to ACP and/or end of life discussions in the context of MS were included, as well as one article on physical disability and one on motor neuron disease, that contributed important contextual information. Researchers independently screened abstracts and extracted data from full-text articles. Using abductive and retroductive analysis, each article was examined for evidence to support or refute ‘context, mechanism, and outcome’ (CMO) hypotheses, using the Integrated Behaviour Model to guide theory development. Quality was assessed according to methodological rigour and relevance of evidence. Those studies providing rich descriptions were synthesised using a realist matrix to identify commonalities across CMO configurations.

Results

Of the 4,034 articles identified, 33 articles were included in the synthesis that supported six CMO hypotheses that identified contexts and mechanisms underpinning engagement in ACP for people with MS and included: acceptance of their situation, prior experiences, confidence, empowerment, fear (of being a burden, of death and of dying) and the desire for autonomy. Acceptance of self as a person with a life-limiting illness was imperative as it enabled people with MS to see ACP as pertinent to them. We identified the context of MS—its long, uncertain disease trajectory with periods of stability punctuated by crisis—inhibited triggering of mechanisms. Similarly, the absence of skills and confidence in advanced communication skills among health professionals prevented possibilities for ACP discussions taking place.

Conclusion

Although mechanisms are inhibited by the context of MS, health professionals can facilitate greater uptake of ACP among those people with MS who want it by developing their skills in communication, building trusting relationships, sharing accurate prognostic information and sensitively discussing death and dying.

The Agony of Choice? Preserved Affective Decision Making in Early Multiple Sclerosis

Background: Cognitive impairment (CI) is an early and frequent symptom of multiple sclerosis (MS). Likewise, affective symptoms (e.g., depression and anxiety) and alterations in the processing of emotional stimuli have been frequently reported. Thus, abilities that integrate affective and cognitive processes such as decision making (DM) based on affective feedback are potentially valuable early diagnostic markers for MS. The available research on this topic, however, is still inconclusive and suffers from methodological issues. Methods: We compared DM ability in a clinically homogeneous cohort of 24 patients with early relapsing-remitting MS (RRMS) and 59 age-matched healthy controls (HCs). A modified version of the Iowa gambling task (IGT) allowed us to control for individual differences in search strategies during the risk exploration phase. Besides standard IGT measures (netscore, obtained play money, and learning index), we also examined reaction times and post-error slowing (PES) patterns as a proxy for abnormalities in the processing of affective feedback. Results: The performance of patients did not significantly deviate from HCs in any standard parameter of the modified IGT. Furthermore, although RRMS patients reacted significantly slower than HCs overall, we found similar patterns of PES in both groups, suggesting similarly efficient processing of affective feedback. Conclusion: We conclude that there is no specific deficit in affective feedback processing in early RRMS. Previous findings of IGT impairments in this patient group may thus not represent a genuine deficit in affective DM but rather be related to sample characteristics, general CI, and/or differences in individual search strategies. Future research should explore the potential influence of lesion volumes and locations on DM ability by employing brain imaging techniques.

The application of Strategy-based Training to Enhance Memory (STEM) in multiple sclerosis: A pilot RCT

New learning and memory (NLM) impairments are common in multiple sclerosis (MS), negatively impacting daily life. Few studies seek to remediate these deficits to improve everyday functioning. Self-generation, spaced learning and retrieval practice have been shown to improve NLM in healthy persons and have been incorporated into an 8-session treatment protocol, Strategy-based Training to Enhance Memory (STEM). STEM teaches participants about each of the techniques, how to apply them in daily life and provides practice. Participants are taught to restructure a memory-demanding situation to optimize self-generation, spaced learning and retrieval practice. This pilot double-blind, placebo-controlled, randomized clinical trial (RCT) tested the efficacy of STEM in 20 learning-impaired participants with clinically definite MS (9 treatment, 11 control). Significant treatment effects were noted on self-report measures of daily functioning (primary outcome). Objective neuropsychological testing approached significance, showing a medium-large effect on verbal NLM. Results suggest that STEM may improve everyday functioning in individuals with MS. A full-scale RCT is warranted to validate findings in a larger sample so that findings may be generalized to the broader MS community.

Neural Correlates of Outcome Anticipation in Multiple Sclerosis

Outcome anticipation is not only a mental preparation for upcoming consequences, but also an essential component of learning and decision-making. Thus, anticipation of consequences is a key process in everyday functioning. The striatum and the ventromedial prefrontal cortex are among the key regions that have been shown to be involved in outcome anticipation. However, while structural abnormalities of these regions as well as altered decision-making have been noted in individuals with multiple sclerosis (MS), neural correlates of outcome anticipation have not been explored in this population. Thus, we examined the neural correlates of outcome anticipation in MS by analyzing brain activation in individuals with MS while they performed a modified version of a card-guessing task. Seventeen MS and 13 healthy controls performed the task while functional magnetic resonance imaging (fMRI) was obtained. To achieve maximal anticipatory response and prevent the possibility of differential performance on the task, participants were presented with monetary rewards only on 50% of the trials. While replicating previous evidence of structural abnormalities of the striatum in MS, our results further showed that individuals with MS exhibited greater activation in the putamen, right hippocampus, and posterior cingulate cortex during outcome anticipation compared to healthy controls. Furthermore, even though there was no strategy that participants could learn in order to predict outcomes, 76% of participants with MS indicated that they used strategies while performing the task. We thus propose that the increased neural activation observed in MS during outcome anticipation might be explained by a failure in recognizing the lack of regularity in the task structure that could result in using strategies to perform the task.

Decision-Making in Multiple Sclerosis Patients: A Systematic Review

Background

Multiple sclerosis (MS) is frequently associated with cognitive and behavioural deficits. A growing number of studies suggest an impact of MS on decision-making abilities. The aim of this systematic review was to assess if (1) performance of MS patients in decision-making tasks was consistently different from controls and (2) whether this modification was associated with cognitive dysfunction and emotional alterations.

Methods

The search was conducted on Pubmed/Medline database. 12 studies evaluating the difference between MS patients and healthy controls using validated decision-making tasks were included. Outcomes considered were quantitative (net scores) and qualitative measurements (deliberation time and learning from feedback).

Results

Quantitative and qualitative decision-making impairment in MS was present in 64.7% of measurements. Patients were equally impaired in tasks for decision-making under risk and ambiguity. A correlation to other cognitive functions was present in 50% of cases, with the highest associations in the domains of processing speed and attentional capacity.

Conclusions

In MS patients, qualitative and quantitative modifications may be present in any kind of decision-making task and can appear independently of other cognitive measures. Since decision-making abilities have a significant impact on everyday life, this cognitive aspect has an influential importance in various MS-related treatment settings.

Decision-making in primary onset middle-age type 2 diabetes mellitus: a BOLD-fMRI study

Although type 2 diabetes mellitus (T2DM) is a well-recognized risk factor for dementia, the neural mechanisms that underlying cognitive impairment in T2DM remain unclear. We used functional magnetic resonance imaging (fMRI) during a computerized version of the Iowa Gambling Task to investigate the neural basis of decision making at the initial onset stage of T2DM. Eighteen newly diagnosed middle-aged T2DM patients, with no previous diabetic treatment history, and 18 matched controls were recruited. Results indicated that T2DM patients made more disadvantageous decisions than controls. Compared to healthy subjects, T2DM patients showed decreased activation in the ventral medial prefrontal cortex (VMPFC), orbitofrontal cortex (OFC) and anterior cingulate cortex, and increased activity in the dorsolateral prefrontal cortex, posterior cingulate cortex, insula and occipital lobes. IGT performance positively correlated with changes in brain activation in the VMPFC and OFC in both groups. Moreover, poor glycemic control was associated with decision-making function both in behavioral and brain activity in the VMPFC and OFC in patients. Conclusively, T2DM patients may suffer from weaknesses in their prefrontal cortex functions that lead to poorer decision-making under ambiguity, at least as assessed by the IGT.

Brain activity, regional gray matter loss, and decision-making in multiple sclerosis

BACKGROUND

Decision-making (DM) abilities deteriorate with multiple sclerosis (MS) disease progression which impairs everyday life and is thus clinically important.

OBJECTIVE

To investigate the underlying neurocognitive processes and their relation to regional gray matter (GM) loss induced by MS.

METHODS

We used a functional magnetic resonance imaging (fMRI) Iowa Gambling Task to measure DM-related brain activity in 36 MS patients and 21 healthy controls (HC). From this activity, we determined neural parameters of two cognitive stages, a deliberation ("choice") period preceding a choice and a post-choice ("feedback") stage reporting decision outcomes. These measures were related to DM separately in intact and damaged GM areas as determined by a voxel-based morphometry analysis.

RESULTS

Severely affected patients (with high lesion burden) showed worse DM-learning than HC ( t = -1.75, p = 0.045), moderately affected (low lesion burden) did not. Activity in the choice stage in intact insular ( t = 4.60, p_{Family-Wise Error [FWE] corrected} = 0.034), anterior cingulate ( t = 4.50, p_FWE = 0.044), and dorsolateral prefrontal areas ( t = 4.43, p_FWE = 0.049) and in insular areas with GM loss ( t = 3.78, p_FWE = 0.011) was positively linked to DM performance across patients with severe tissue damage and HC. Furthermore, activity in intact orbitofrontal areas was positively linked to DM-learning during the feedback stage across these participants ( t = 4.49, p_FWE = 0.032). During none of the stages, moderately affected patients showed higher activity than HC, which might have indicated preserved DM due to compensatory activity.

CONCLUSION

We identified dysregulated activity linked to impairment in specific cognitive stages of reward-related DM. The link of brain activity and impaired DM in areas with MS-induced GM loss suggests that this deficit might be tightly coupled to MS neuropathology.

Regular exercise promotes memory function and enhances hippocampal neuroplasticity in experimental autoimmune encephalomyelitis mice

Multiple sclerosis (MS) is a progressive condition affecting the central nervous system (CNS), and is characterized by the development of demyelinated lesions and plaques in the brain and spinal cord. Exercise is beneficial against dementia in elderly patients, so we investigated the effects of exercise on memory in relation to hippocampal demyelination and neuroplasticity in a mouse model of MS (experimental autoimmune encephalomyelitis [EAE]). Mice were randomly divided into three groups: Sham, EAE, and EAE and exercise (EAE+EX). EAE+EX mice exercised five times a week for 4weeks, and all mice performed step-down avoidance tasks in order to verify memory ability. We analyzed changes in myelin basic protein (MBP), 2',3'-Cyclic nucleotide 3'-phosphodiesterase (CNPase), 5-bromo-2'-deoxyuridine (brdU), doublecortin (DCX), bcl-2, bax, TUNEL, caspase-3, and brain derived neurotrophic factor (BDNF) via immunoassay or histological staining. We found decreased memory ability in EAE mice, accompanied by impaired myelination, increased apoptosis and cell proliferation, and decreased BDNF in the hippocampus. The memory decline and changes in demyelination, apoptosis, BDNF, and cell proliferation were partially reversed in EAE+EX mice. Our findings suggest that in patients with MS, regular exercise may benefit cognitive function by rescuing some hippocampal cellular and molecular impairments.

Impairment of decision-making in multiple sclerosis: A neuroeconomic approach

OBJECTIVE

To assess the decision-making impairment in patients with multiple sclerosis (MS) and how they relate to other cognitive domains.

METHODS

We performed a cross-sectional analysis in 84 patients with MS, and 21 matched healthy controls using four tasks taken from behavioral economics: (1) risk preferences, (2) choice consistency, (3) delay of gratification, and (4) rate of learning. All tasks were conducted using real-world reward outcomes (food or money) in different real-life conditions. Participants underwent cognitive examination using the Brief Repeatable Battery-Neuropsychology.

RESULTS

Patients showed higher risk aversion (general propensity to choose the lottery was 0.51 vs 0.64, p = 0.009), a trend to choose more immediate rewards over larger but delayed rewards ( p = 0.108), and had longer reactions times ( p = 0.033). Choice consistency and learning rates were not different between groups. Progressive patients chose slower than relapsing patients. In relation to general cognitive impairments, we found correlations between impaired decision-making and impaired verbal memory ( r = 0.29, p = 0.009), visual memory ( r = -0.37, p = 0.001), and reduced processing speed ( r = -0.32, p = 0.001). Normalized gray matter volume correlated with deliberation time ( r = -0.32, p = 0.005).

CONCLUSION

Patients with MS suffer significant decision-making impairments, even at the early stages of the disease, and may affect patients' quality and social life.

Information processing speed in multiple sclerosis: Past, present, and future

BACKGROUND

Information processing speed (IPS) is a prevalent cognitive impairment in multiple sclerosis (MS).

OBJECTIVES

This review aims to summarize the methods applied to assess IPS in MS and its theoretical conceptualization. A PubMed search was performed to select articles published between 1 January 2004 and 31 December 2013, resulting in 157 articles included.

RESULTS

The majority (54%) of studies assessed IPS with heterogeneous samples (several disease courses). Studies often report controlling for presence of other neurological disorders (60.5%), age (58.6%), education (51.6%), alcohol history (47.8%), or use of steroids (39.5%). Potential confounding variables, such as recent relapses (50.3%), history of developmental disorders (19.1%), and visual problems (29.9%), were often neglected. Assessments used to study IPS were heterogeneous (ranging from simple to complex tasks) among the studies under review, with 62 different tasks used. Only 9.6% of articles defined the construct of IPS and 22.3% discussed IPS in relation to a theoretical model.

FUTURE DIRECTIONS

The challenges for the upcoming decade include clarification of the definition of IPS as well as its theoretical conceptualization and a consensus on assessment. Based on the results obtained, we propose a new theoretical model, the tri-factor model of IPS.

The grey matter correlates of impaired decision-making in multiple sclerosis

OBJECTIVE

People with multiple sclerosis (MS) have difficulties with decision-making but it is unclear if this is due to changes in impulsivity, risk taking, deliberation or risk adjustment, and how this relates to brain pathology.

METHODS

We assessed these aspects of decision-making in 105 people with MS and 43 healthy controls. We used a novel diffusion MRI method, diffusion orientational complexity (DOC), as an index of grey matter pathology in regions associated with decision-making and also measured grey matter tissue volumes and white matter lesion volumes.

RESULTS

People with MS showed less adjustment to risk and slower decision-making than controls. Moreover, impaired decision-making correlated with reduced executive function, memory and processing speed. Decision-making impairments were most prevalent in people with secondary progressive MS. They were seen in patients with cognitive impairment and those without cognitive impairment. On diffusion MRI, people with MS showed DOC changes in all regions except the occipital cortex, relative to controls. Risk adjustment correlated with DOC in the hippocampi and deliberation time with DOC in the medial prefrontal, middle frontal gyrus, anterior cingulate and caudate parcellations and with white matter lesion volumes.

CONCLUSIONS

These data clarify the features of decision-making deficits in MS, and provide the first evidence that they relate to grey and white matter abnormalities seen using MRI.

Alteration profile of executive functions in multiple sclerosis

OBJECTIVE

Executive functions (EF) in multiple sclerosis (MS) have been only partially studied, mainly trough the evaluation of subfunctions. The main objective was to analyse the EF alteration profile in a patients with MS sample.

PARTICIPANTS AND METHODS

Case-control study, 100 patients with MS and 30 controls were evaluated by the following tests: Comprehensive Trail Making Test, Stroop Test, Wisconsin Card Sorting Test, picture completion, letter-number sequencing, comprehension and similarities of the WAIS-III scale, phonological and semantic fluency, zoo map test, temporal judgment and behavioural Dysexecutive Questionnaire (DEX-Q) of the Behavioural Assessment of the Dysexecutive Syndrome. Scores below normative values were considered pathological. Factorial analysis was used to simplify the deficits, and multiple regression and ANOVA statistics were used to analyse the relationship between clinical and cognitive variables.

RESULTS

Seventy-four patients had a recurrent-relapsing course, the mean degree of disability by Expanded disability Status Scale (EDSS) was 2.7 and the mean time of evolution was 9.94 years. Eighty-five per cent presented alterations in 3 or more EF tests and 71% in 5 or more. In the factorial analysis, three groups of functions were involved: (i) cognitive flexibility (ii) inhibition and (iii) abstraction ability. Patients with a progressive course and a high EDSS had a significantly worse performance (P < 0.05). The patients showed a low awareness of their deficit in the DEX-Q.

CONCLUSIONS

Cognitive flexibility, inhibition and abstraction ability were the three components of EF most deficient. The patients with the worst performance were those with progressive forms and a high EDSS.

Decision-making under explicit risk is impaired in multiple sclerosis: relationships with ventricular width and disease disability

BACKGROUND

Decision-making is an essential function of everyday life. Decision-making under explicit risk requires developing advantageous decision strategies based on fixed outcomes (e.g., probabilities of winning or losing a bet). Decision-making and its neural substrates have been rarely studied in MS. We expected performance in decision-making under risk to be lowered in MS patients, and negatively correlated with disease-related disability, cognition, and ventricular width.

METHODS

Three groups were included: 32 MS patients and 20 healthy controls were examined with conventional neuropsychological tests and the Game-of-Dice Task (GDT) assessing decision-making under explicit risk. Linear 2-D ventricular width was assessed on MS patients' clinical MRIs and compared to a third group, 20 non-MS neurological control patients.

RESULTS

Compared to healthy controls, MS patients showed impaired GDT and neuropsychological performance, depending on the MS-subtype (relapsing-remitting (RR), n = 22; secondary progressive, n = 10) and disability severity among RR-MS patients. In MS patients, GDT performance correlated with processing speed, intercaudate ratio, and third ventricle ratio (p's < 0.05). Mediation analysis showed that the link between GDT performance and processing speed was fully explained by ventricular size.

CONCLUSION

Decision-making under explicit risk was reduced in MS patients, but only those with more pronounced disability. Independent of processing speed, decision-making under explicit risk correlates inversely with central atrophy in MS.

Cognitive rehabilitation in multiple sclerosis: the role of plasticity

Cognitive deficits are common in multiple sclerosis (MS), documented at many stages of the disease. Both structural and functional neuroimaging have demonstrated a relationship with cognitive abilities in MS. Significant neuroplasticity of cognitive functions in individuals with MS is evident. Homologous region adaptation, local activation expansion, and extra-region recruitment all occur in an effort to maintain cognitive functioning. While much of this neuroplasticity is adaptive, it may also be maladaptive, particularly in individuals that are demonstrating significant cognitive impairment and/or with disease progression. This maladaptive neuroplasticity may come at the cost of other cognitive functions. Studies of cognitive rehabilitation efficacy have also recently applied neuroimaging techniques to establish outcome. Researchers have successfully applied various neuroimaging techniques to study the effects of cognitive rehabilitation in MS including task-based fMRI and resting state functional connectivity across multiple realms of cognition including episodic memory, executive functioning, attention, and processing speed. These studies have demonstrated neuroplasticity in the brains of persons with MS through the documentation of changes at the level of the cerebral substrate from before to after non-invasive, non-pharmacological, behavioral treatment for deficits in cognition. Future research should seek to identify adaptive versus maladaptive neuroplasticity associated with specific cognitive rehabilitation programs within all MS phenotypes to foster the validation of the most effective cognitive rehabilitation interventions for persons with MS.

Cognitive correlates of under-ambiguity and under-risk decision making in high-functioning patients with relapsing remitting multiple sclerosis

INTRODUCTION

Impairment of decision making in relapsing remitting multiple sclerosis is still controversial, and its neuropsychological correlates have never been explored thoroughly, especially in patients with minimal physical and cognitive deficits. In the present study we investigated the cognitive underpinnings of decision making under ambiguous and explicit conditions in patients with very mild relapsing remitting multiple sclerosis, using a dice and a card gambling game.

METHOD

The study sample included 60 patients and 35 healthy subjects. In the Game of Dice Task, winning and losing probabilities are obvious to the subject, while in the Iowa Gambling Task they are initially ambiguous and have to be gradually identified. Performance at the two tasks was correlated with scores obtained at tests investigating cognitive processing speed, memory, language and executive functions.

RESULTS

Patients' performance did not differ from that of controls at either gambling task. There was only a trend for them to be significantly slower than healthy subjects in progressively recognizing advantageous decks in the Iowa Gambling Task. While the Game of Dice was unrelated to neuropsychological tests, predictors of performance at the Iowa task were Letter Fluency and the Symbol Digit Modalities Test for the initial, under-ambiguity, trials and the Wisconsin Card Sorting Test for the last, purely under-risk, trials.

CONCLUSIONS

Our results suggest that high-functioning patients with relapsing remitting multiple sclerosis are substantially capable of making advantageous decisions, even if they may be slower in processing options and shifting strategy when selection criteria are not explicit.

Decision-making impairment in patients with multiple sclerosis: a case-control study

OBJECTIVES

To assess decision-making under explicit risk conditions in relapsing-remitting multiple sclerosis patients and its relationship to decisions made under conditions of ambiguity. To assess cognitive functions related to decision-making performance in patients with multiple sclerosis (MS).

SETTING

MS center in Buenos Aires, Argentina.

PARTICIPANTS

27 patients with relapsing-remitting multiple sclerosis and 27 sex-matched, age-matched and education-matched healthy controls.

INTERVENTION

Neuropsychological assessment and decision-making evaluation using the Game of Dice Task and the Iowa Gambling Task.

OUTCOMES

Game of Dice Task and the Iowa Gambling Task scores.

RESULTS

Patients with MS showed significantly poorer performance on the Game of Dice Task, choosing disadvantageous dice more often (p=0.019), as well as significantly lower overall scores in the Iowa Gambling Task (p=0.007). Block analysis showed that patients with MS and controls had scores that were comparable for blocks 1 and 2 (p=0.15 and p=0.24, respectively). Conversely, patients with MS scored poorly on blocks 4 (p=0.003) and 5 (p=0.023), the last two of the test, corresponding to decision-making under conditions of risk. Finally, the Game of Dice Task performance together with the last three blocks of the Iowa Gambling Task were correlated with visuospatial learning, processing speed and working memory but not with executive functioning.

CONCLUSIONS

Patients with MS showed deficits in decision-making under risk conditions, which might be related to deficits in visuospatial learning, processing speed and working memory.

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.

Multiple sclerosis decreases explicit counterfactual processing and risk taking in decision making

INTRODUCTION

Deficits in decision making (DM) are commonly associated with prefrontal cortical damage, but may occur with multiple sclerosis (MS). There are no data concerning the impact of MS on tasks evaluating DM under explicit risk, where different emotional and cognitive components can be distinguished.

METHODS

We assessed 72 relapsing-remitting MS (RRMS) patients with mild to moderate disease and 38 healthy controls in two DM tasks involving risk with explicit rules: (1) The Wheel of Fortune (WOF), which probes the anticipated affects of decisions outcomes on future choices; and (2) The Cambridge Gamble Task (CGT) which measures risk taking. Participants also underwent a neuropsychological and emotional assessment, and skin conductance responses (SCRs) were recorded.

RESULTS

In the WOF, RRMS patients showed deficits in integrating positive counterfactual information (p<0.005) and greater risk aversion (p<0.001). They reported less negative affect than controls (disappointment: p = 0.007; regret: p = 0.01), although their implicit emotional reactions as measured by post-choice SCRs did not differ. In the CGT, RRMS patients differed from controls in quality of DM (p = 0.01) and deliberation time (p = 0.0002), the latter difference being correlated with attention scores. Such changes did not result in overall decreases in performance (total gains).

CONCLUSIONS

The quality of DM under risk was modified by MS in both tasks. The reduction in the expression of disappointment coexisted with an increased risk aversion in the WOF and alexithymia features. These concomitant emotional alterations may have implications for better understanding the components of explicit DM and for the clinical support of MS patients.

Progressive decline of decision-making performances during multiple sclerosis

The purpose of this study was to evaluate longitudinally, using the Iowa Gambling Task (IGT), the dynamics of decision-making capacity at a two-year interval (median: 2.1 years) in a group of patients with multiple sclerosis (MS) (n = 70) and minor neurological disability [Expanded Disability Status Scale (EDSS) < or = 2.5 at baseline]. Cognition (memory, executive functions, attention), behavior, handicap, and perceived health status were also investigated. Standardized change scores [(score at retest-score at baseline)/standard deviation of baseline score] were computed. Results showed that IGT performances decreased from baseline to retest (from 0.3, SD = 0.4 to 0.1, SD = 0.3, p = .005). MS patients who worsened in the IGT were more likely to show a decreased perceived health status and emotional well-being (SEP-59; p = .05 for both). Relapsing rate, disability progression, cognitive, and behavioral changes were not associated with decreased IGT performances. In conclusion, decline in decision making can appear as an isolated deficit in MS.

Cognitive impairment in multiple sclerosis

Multiple sclerosis (MS) is a progressive disease of the CNS that is characterised by widespread lesions in the brain and spinal cord. MS results in motor, cognitive, and neuropsychiatric symptoms, all of which can occur independently of one another. The common cognitive symptoms include deficits in complex attention, efficiency of information processing, executive functioning, processing speed, and long-term memory. These deficits detrimentally affect many aspects of daily life, such as the ability to run a household, participate fully in society, and maintain employment--factors that can all affect the overall quality of life of the patient. The increased use of neuroimaging techniques in patients with MS has advanced our understanding of structural and functional changes in the brain that are characteristic of this disease, although much remains to be learned. Moreover, examination of efforts to treat the cognitive deficits in MS is still in the early stages.

Preserved decision making ability in early multiple sclerosis

BACKGROUND

The purpose of this study was to assess decision making in patients with multiple sclerosis (MS) at the earliest clinically detectable time point of the disease.

METHODS

Patients with definite MS (n = 109) or with clinically isolated syndrome (CIS, n = 56), a disease duration of 3 months to 5 years, and no or only minor neurological impairment (Expanded Disability Status Scale [EDSS] score 0-2.5) were compared to 50 healthy controls using the Iowa Gambling Task (IGT).

RESULTS

The performance of definite MS, CIS patients, and controls was comparable for the two main outcomes of the IGT (learning index: p = 0.7; total score: p = 0.6). The IGT learning index was influenced by the educational level and the co-occurrence of minor depression. CIS and MS patients developing a relapse during an observation period of 15 months dated from IGT testing demonstrated a lower learning index in the IGT than patients who had no exacerbation (p = 0.02). When controlling for age, gender and education, the difference between relapsing and non-relapsing patients was at the limit of significance (p = 0.06).

CONCLUSION

Decision making in a task mimicking real life decisions is generally preserved in early MS patients as compared to controls. A possible consequence of MS relapsing activity in the impairment of decision making ability is also suspected in the early phase of MS.

Cognitive impairments in relapsing-remitting multiple sclerosis: a meta-analysis

There is debate in the literature regarding the magnitude, nature, and influence of cognitive impairment in individuals with relapsing-remitting multiple sclerosis (RRMS). Therefore, we conducted a meta-analysis that quantified the overall magnitude of cognitive impairment in individuals with RRMS and identified the domains of cognition and clinical/demographic variables that were moderators of the overall effect. We included 57 studies with 3891 participants that yielded a total of 755 effect sizes. Overall, there was a moderate decline in cognitive functioning in individuals with RRMS compared with healthy controls. Larger effects were observed in cognitive domains of motor functioning, mood status and memory and learning. Regarding demographic and clinical variables, age and gender were moderators of cognitive impairment in all cognitive domains, whereas neurological disability and disease duration primarily moderated performance on tasks assessing memory and learning.