Decision making under ambiguity in temporal lobe epilepsy: does the location of the underlying structural abnormality matter?

Decision-making under ambiguity after frontal lobe resection for epilepsy

PURPOSE

Decision-making is crucial to daily life and can impact our society as well as economic conditions. Although the frontal lobes have been identified as important for decision-making, this capacity has only been studied to a limited extent in frontal lobe epilepsy and not at all after frontal lobe resection (FLR) for epilepsy. This study aimed to explore decision-making under ambiguity after FLR for epilepsy.

METHODS

Fourteen patients having undergone FLR for epilepsy completed the Iowa Gambling Task (IGT) which is a widely used tool to measure decision-making under ambiguity. Iowa Gambling Task scores included in the analysis were: total net score, separate scores from five blocks across the test, and a change score (last block of IGT minus first block). A group of healthy controls (n = 30) was used as a comparison. Associations between IGT and standardized neuropsychological methods for assessment of executive functions, self-rating questionnaires of mental health, fatigue, and behavior linked to frontal lobe dysfunction were also investigated.

RESULTS

The patient group performed inferior to controls at the final block of the IGT (p =.001).A group difference in IGT change scores was found (p =.005), reflectingthe absence of a positive change in performance over time for the FLR group compared to the control group. Correlations with tests of executive functions as well as self-rating scales were mainly statistically nonsignificant.

CONCLUSIONS

This study shows that patients having undergone FLR for epilepsy have difficulties with decision-making under ambiguity. The performance illustrated a failure to learn throughout the task. Executive as well as emotional deficits may impact decision-making processes in this patient group and need to be considered in further studies. Prospective studies with larger cohorts are needed.

Choosing cesarean section over natural birth: Challenges of decision making among pregnant women with pre-eclampsia in Ado-Ekiti

OBJECTIVE

Although Caesarean section has greatly improved obstetric care throughout the world, there is a great aversion to caesarean section in developing countries. This study was carried out to examine the rate at which pregnant women with Pre-eclampsia decide to choose caesarean section over natural birth.

STUDY DESIGN

A descriptive study was conducted among a sample of 112 pregnant women with Pre-eclampsia, aged 18-40 years, whose gestation period has exceeded 20 weeks and are registered in the hospitals. The sample selection was purposive.

MAIN OUTCOME MEASURES

Data collection was done through self-administered structured questionnaire. Data analysis was presented using simple percentages.

RESULTS

94% of respondents had no prior information about Pre-eclampsia and its associated complications. Pre-eclampsia has a prevalence rate of 12.3% among respondents in Ado-Ekiti as at the time this study was conducted. 38% of respondent favored caesarean section because they believed it is safer, less painful with little or no complications. If caesarean section is given as an only medical option for safe childbirth to respondents who preferred natural birth, 46.4% would opt for religious interventions while 10.7% would opt for traditional healthcare.

CONCLUSIONS

Respondents who preferred natural birth would not choose caesarean section because of fear, cultural belief, religious beliefs and the cost. Level of education, religion and employment status were found to influence respondents' decision to choose. Hence the need to encourage research in awareness creation, patient education and best ways to assist patients decide on mode of delivery and plan on how to finance treatment.

Comparison of decision-making under ambiguity in patients with temporal lobe and frontal lobe epilepsy

OBJECTIVE

The effect of the frontal lobe on cognitive functions is a subject that has been studied frequently. However, cognitive impairments that can be seen in frontal lobe epilepsy are less addressed. In previous studies on decision-making disorders in patients with epilepsy, patients with temporal lobe epilepsy (TLE) were frequently studied, and it was reported that decision-making disorders could be encountered in this patient group. In this study, we aimed to compare the decision-making performance of patients with cryptogenic frontal lobe epilepsy (FLE) and TLE in ambiguous situations.

METHODS

Twenty patients with TLE (mean age: 34.10 ± 11.71 years) and 20 patients with FLE (mean age: 32.25 ± 11.92 years) were enrolled in the study and their cognitive performance was compared with 20 healthy controls (mean age: 33.15 ± 13.66 years). Neuropsychological tests were performed on the participants for sleep, depression, anxiety, impulsivity, intelligence, attention, language functions, memory and learning, and frontal axis functions. Decision-making performance in ambiguous situations was studied using the Iowa Gambling Task (IGT).

RESULTS

Iowa Gambling Task performances of patients with FLE and TLE were found to be worse than in healthy controls (p = 0.049). Although there was no statistically significant difference when the decision-making of patients with TLE and FLE was compared, it was observed that patients with FLE chose higher risk cards compared with those with TLE. The performances of the neuropsychological subgroup tests of patients with TLE and FLE in attention, language functions, memory and learning, and frontal axis functions were found to be significantly worse than in healthy subjects.

CONCLUSION

Decision-making in patients with TLE and FLE in ambiguous situations is similarly impaired compared with healthy controls.

Factors Determining the Success of Decision Making and Performance of Portuguese Companies

This paper empirically examines the impact of the quality of information and control system (the internal control system, the accounting information system, the financial information, and the non-financial information) on decision-making success and business performance. It follows a quantitative approach. An online questionnaire was developed and applied to the managers of Portuguese companies. The evaluation of the theoretical model was performed using the AMOS statistical software and applying the structural equation model technique. Based on 381 observations, the results show that the model variables explain about 30% and 70% of the variance of financial and non-financial performance, respectively. This study proves to be relevant not only for the development of the literature, as it evaluates an original and complex model, but also for managers, because it identifies the factors that contribute to the success of Portuguese companies.

Kindling of the basolateral or central nucleus of the amygdala increases suboptimal choice in a rat gambling task and increases motor impulsivity in risk-preferring animals

Impairments in decision making under uncertainty, as measured by the Iowa Gambling Task (IGT), are observed in persons suffering from temporal lobe epilepsy (TLE), in which seizures originate in the amygdala and hippocampal formations. Gambling disorder is also more prevalent in this population. Individuals with amygdala damage show similar deficits in decision-making, as do rats with lesions restricted to the basolateral amygdala (BLA) performing an analogous rat gambling task (rGT), yet whether hyperstimulation of the BLA impacts risky decision-making has yet to be demonstrated. We therefore investigated whether kindling of the BLA affected rGT performance. In this task, sugar pellet profits are maximised through consistent selection of options associated with smaller per-trial gains but shorter punishing time-outs. Just as in the IGT, subjects must avoid the risky options, as penalties are disproportionately high despite the higher reward available. Most rats adopt the optimal strategy, but some instead make high numbers of risky, disadvantageous choices. Once stable choice preferences had been established on-task, sixteen male Long Evans rats were implanted unilaterally with a bipolar electrode targeting the BLA and stimulated twice daily until three stage five seizures had been elicited. The electrodes revealed to be nearly evenly places in the BLA and the Central Nucleus of the Amygdala (CeA). Kindling transiently increased choice of the option paired with the smallest reward but also the lowest level of punishment- a risk-averse, but suboptimal, choice. Risk-preferring rats also made more premature responses, a marker of motor impulsivity, and were faster to make a choice, whereas these variables were unaffected in optimal decision-makers. These data suggest epileptiform activity originating within the amygdala can impair choice and promote impulsivity, at least in some individuals.

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.

Lamotrigine as a mood stabilizer: insights from the pre-clinical evidence

INTRODUCTION

Lamotrigine (LTG) is a well-established anticonvulsant that is also approved for the prevention of mood relapses in bipolar disorder. However, the mechanisms underlying LTG mood stabilizing effects remain unclear. Areas covered: Herein, the pre-clinical evidence concerning LTG's' mode of action in depression and mania is reviewed. Bottlenecks and future perspectives for this expanding and promising field are also discussed. Pre-clinical studies have indicated that neurotransmitter systems, especially serotoninergic, noradrenergic and glutamatergic, as well as non-neurotransmitter pathways such as inflammation and oxidative processes might play a role in LTG's antidepressant effects. The mechanisms underlying LTG's anti-manic properties remain to be fully explored, but the available pre-clinical evidence points out to the role of glutamatergic neurotransmission, possibly through AMPA-receptors. Expert opinion: A major limitation of current pre-clinical investigations is that there are no experimental models that recapitulate the complexity of bipolar disorder. Significant methodological differences concerning time and dose of LTG treatment, administration route, animal strains, and behavioral paradigms also hamper the reproducibility of the findings, leading to contradictory conclusions. Moreover, the role of other mechanisms (e.g. inositol phosphate and GSK3β pathways) implicated in the mode of action of different mood-stabilizers must also be consolidated with LTG.

Risky Decision Making in Juvenile Myoclonic Epilepsy

It is not known whether patients with juvenile myoclonic epilepsy (JME) differ from healthy people in decision making under risk, i.e., when the decision-making context offers explicit information about options, probabilities, and consequences already from the beginning. In this study, we adopted the Game of Dice Task-Double to investigate decision making under risk in a group of 36 patients with JME (mean age 25.25/SD 5.29 years) and a group of 38 healthy controls (mean age 26.03/SD 4.84 years). Participants also underwent a comprehensive neuropsychological assessment focused on frontal executive functions. Significant group differences were found in tests of psychomotor speed and divided attention, with the patients scoring lower than the controls. Importantly, patients made risky decisions more frequently than controls. In the patient group, poor decision making was associated with poor executive control, poor response inhibition, and a short interval since the last seizure episode. Executive control and response inhibition could predict 42% of variance in the frequency of risky decisions. This study indicates that patients with JME with poorer executive functions are more likely to make risky decisions than healthy controls. Decision making under risk is of major importance in every-day life, especially with regard to treatment decisions and adherence to long-term medical therapy. Since even a single disadvantageous decision may have long-lasting consequences, this finding is of high relevance.

Decision-making in patients with temporal lobe epilepsy: Delay gratification ability is not impaired in patients with hippocampal sclerosis

BACKGROUND

Decision-making abilities have rarely been examined in patients with temporal lobe epilepsy related to hippocampal sclerosis (TLE-HS). We aimed to investigate the ability to delay gratification, a decision-making subdomain, in patients with intractable TLE-HS and to verify the association of delay gratification performance and cool executive function tests.

METHODS

We evaluated 27 patients with TLE-HS (mean age: 35.46 [±13.31] years; 7 males) and their cognitive performance was compared with that of 27 age- and gender-matched healthy controls (mean age: 35.33 [±12.05] years; 7 males), without epilepsy and psychiatric disorders. Patients were assessed using the delay discounting task (DDT) and tests of attention, shifting, inhibitory control, and concept formation. Results were correlated with clinical epilepsy variables such as age of onset, epilepsy duration, AED use, history of status epilepticus, febrile seizures, and the presence of generalized seizures. Statistical analysis was performed using one-way ANCOVA with years of education as a confounding factor.

RESULTS

Patients and controls demonstrated similar performance on DDT, showing similar discount rate (p=0.935) and probability rate (p=0.585). Delay gratification was not related to cool executive function tests (Digit Span, Stroop Color Test, Trail Making Test, Wisconsin Card Sorting Test, and Connors' CPT). History of status epilepticus, presence of generalized seizures and higher seizure frequency, age at onset, and epilepsy duration had a significant impact on DDT.

CONCLUSION

Patients with intractable TLE-HS showed unimpaired delay gratification abilities, being able to accept a higher delay and a lower amount of chance for receiving a higher reward in the future. Clinical variables related to the epilepsy severity impacted the performance on delay gratification. Impairment on cool aspects of executive function was unrelated to this decision-making domain.

The neural bases for devaluing radical political statements revealed by penetrating traumatic brain injury

Given the determinant role of ventromedial prefrontal cortex (vmPFC) in valuation, we examined whether vmPFC lesions also modulate how people scale political beliefs. Patients with penetrating traumatic brain injury (pTBI; N = 102) and healthy controls (HCs; N = 31) were tested on the political belief task, where they rated 75 statements expressing political opinions concerned with welfare, economy, political involvement, civil rights, war and security. Each statement was rated for level of agreement and scaled along three dimensions: radicalism, individualism and conservatism. Voxel-based lesion-symptom mapping (VLSM) analysis showed that diminished scores for the radicalism dimension (i.e. statements were rated as less radical than the norms) were associated with lesions in bilateral vmPFC. After dividing the pTBI patients into three groups, according to lesion location (i.e. vmPFC, dorsolateral prefrontal cortex [dlPFC] and parietal cortex), we found that the vmPFC, but not the dlPFC, group had reduced radicalism scores compared with parietal and HC groups. These findings highlight the crucial role of the vmPFC in appropriately valuing political behaviors and may explain certain inappropriate social judgments observed in patients with vmPFC lesions.

Attention and executive functions in a rat model of chronic epilepsy

OBJECTIVE

Temporal lobe epilepsy is a relatively frequent, invalidating, and often refractory neurologic disorder. It is associated with cognitive impairments that affect memory and executive functions. In the rat lithium-pilocarpine temporal lobe epilepsy model, memory impairment and anxiety disorder are classically reported. Here we evaluated sustained visual attention in this model of epilepsy, a function not frequently explored.

METHODS

Thirty-five Sprague-Dawley rats were subjected to lithium-pilocarpine status epilepticus. Twenty of them received a carisbamate treatment for 7 days, starting 1 h after status epilepticus onset. Twelve controls received lithium and saline. Five months later, attention was assessed in the five-choice serial reaction time task, a task that tests visual attention and inhibitory control (impulsivity/compulsivity). Neuronal counting was performed in brain regions of interest to the functions studied (hippocampus, prefrontal cortex, nucleus basalis magnocellularis, and pedunculopontine tegmental nucleus).

RESULTS

Lithium-pilocarpine rats developed motor seizures. When they were able to learn the task, they exhibited attention impairment and a tendency toward impulsivity and compulsivity. These disturbances occurred in the absence of neuronal loss in structures classically related to attentional performance, although they seemed to better correlate with neuronal loss in hippocampus. Globally, rats that received carisbamate and developed motor seizures were as impaired as untreated rats, whereas those that did not develop overt motor seizures performed like controls, despite evidence for hippocampal damage.

SIGNIFICANCE

This study shows that attention deficits reported by patients with temporal lobe epilepsy can be observed in the lithium-pilocarpine model. Carisbamate prevents the occurrence of motor seizures, attention impairment, impulsivity, and compulsivity in a subpopulation of neuroprotected rats.

[Advances in research on cognitive function related to temporal lobe epilepsy: focus on social cognitive function]

Research on cognitive function related to temporal lobe epilepsy has thus far focused on memory, language, and general intelligence. Recently, however, the concept of social cognitive function has been proposed in the field of neuropsychology. Social cognitive function refers collectively to the higher cognitive functions that are essential in our social lives, and its representative aspects are facial expression recognition and decision-making. Emotional processing centered around the amygdala is thought to play a key role in the neural mechanism of this function. We conducted a study on the social cognitive function (decision-making) of patients with temporal lobe epilepsy, and found that this function is reduced in these patients, and that the right amygdalo-hippocampal complexes play an important role. In order to ensure the best possible treatment for epilepsy patients, it is necessary not only to make an accurate diagnosis and provide appropriate treatment, but also to provide support for enabling a smoother social life from the perspective of social cognitive function. Future research developments in this field are expected to contribute to total management in medical care for epilepsy patients.

Anchor effects in decision making can be reduced by the interaction between goal monitoring and the level of the decision maker's executive functions

Models of decision making postulate that interactions between contextual conditions and characteristics of the decision maker determine decision-making performance. We tested this assumption by using a possible positive contextual influence (goals) and a possible negative contextual influence (anchor) in a risky decision-making task (Game of Dice Task, GDT). In this task, making advantageous choices is well known to be closely related to a specific decision maker variable: the individual level of executive functions. One hundred subjects played the GDT in one of four conditions: with self-set goal for final balance (n = 25), with presentation of an anchor (a fictitious Top 10 list, showing high gains of other participants; n = 25), with anchor and goal definition (n = 25), and with neither anchor nor goal setting (n = 25). Subjects in the conditions with anchor made more risky decisions irrespective of the negative feedback, but this anchor effect was influenced by goal monitoring and moderated by the level of the subjects' executive functions. The findings imply that impacts of situational influences on decision making as they frequently occur in real life depend upon the individual's cognitive abilities. Anchor effects can be overcome by subjects with good cognitive abilities.