Different Types of Decision Making Impairments in Anorexia Nervosa

Research on neurocognitive aspects in Anorexia Nervosa (AN) has outlined a cognitive profile characterized by deficiency in the ability to set-shifting (cognitive flexibility) and weak central coherence. A smaller agreement emerges in relation to the compromission of decisional profiles frequently observed in patients with AN since both the complexity of the pathology and the executive function itself make it unclear the nature of these alterations and its relationships with specific or independent clinical and enviornmental variables. The aim of this study was: to investigate different types of decision-making (DM) ability, veridical and adaptive, in a sample of patients with AN using the Iowa Gambling Task and the Cognitive Bias Task; to analyze test performance using a specific cognitive model for the Iowa Gambling Task (Expectancy Valence Learning Model), and to study the relationship with clinical features, focusing on their relationship with neuropsychological profiles and clinical variables; to explore the neural correlations of the two tasks with functional connectivity; to observe the the impact of the genetic profile on different types of DM. Materials and Methods: The sample, consisting of 310 female subjects with AN lifetime and 301 female subjects without diagnosis of lifetime eating disorders, was tested in relation to DM abilities through the Iowa Gambling Task and cognitive Bias Task. All of the participants completed a baseline assessment including the Structured Clinical Interview (SCID) for the DSM-IV, section for eating disorders, and neuropsychological tests including the Wisconsin Card Sorting Test, and Trail Making Test for assessing abilities of abstraction and cognitive flexibility; 10 "and 30" interference memory test for evaluation of working memory, Stop Signal Task for evaluation of inibitory control. The Expectancy Valence Model (EVM) was used to analyze the results obtained in IGT. A genotyping was performed to evaluate the impact of the major polymorphisms implicated in decision-making (158 Val → Met) of the COMT gene and single nucleotide A / G polymorphism (SNP rs25531) of the serotonin carrier gene 5 - HTTLPR. In a smaller subgroup of 35 AN and 34 Healthy control seed based resting state Functional connectivity was explored. Compared to the group of healthy subjects, the decision-making profile of patients suffering from AN was worse in both Iowa Gambling Task (IGT), which evaluates veridical DM, and Cognitive Bias Task (Cbias), which evaluates adaptive DM, regardless of the diagnostic subtype (restrictive vs. binging/purging), psychopathology severity, scholarity, manual 3 dominance or outcome specific treatment. However in IGT the affective decision-making seems to be independent of IMC, conversely in Cbias the adaptive decisional profile was influenced by underweight. Both types of decision-making in patients were not affected by neurocognitive or clinical variables considered. The unfavorable geotype in AN resulted the homozygous for the met allele of the Comt gene and for the short variant of the serotonin transporter gene. The resting functional connectivity explored on the seeds of interest (executive network, orbitofrontal cortex, accumbens and amygdala) in a subgroup of patients and controls showed significantly different patterns of correlation with the scores of IGt and Cbias. In addition, different resting neural patterns appear to be involved in the two different tasks considered. Only in the AN group a positive correlation between the scores on IGT and the activity of the amygdala resulted. In AN group an higher coactivation within the executive, accumbens and orbitofrontal networks was linked to higher context-independency decisional style assessed with CBias, whereas for the executive network the opposite was true for healthy women. In summary our results confirm an impairment of different types of decision making in AN and highlitght the importance of assessing decisional processes with different specific tasks in clinical sample. In particular different maladaptative strategies are associated with ineffective decisional profiles in AN, consisting in a “myopia for the future” and “anxiety inhibition” in veridical situations and in a difficulty to update/review one’s own mindset according to new environmental stimuli (context indipendent reasoning strategies) in adaptive decisional framework. The severity of malnurishment seems to influence adaptive decisional style conferring a bias toward a context indipent reasoning, suggesting the need of metacognitive approach to help patients to be more aware of their tendency to automatically use selection bias in DM contexts. Genetic polimorphysms may in part account for the impaired decision making observed in AN patients, with a negative impact of met Comt allele and the short variant of 5HTTLPR polymorphism. Functional connectivity suggests the presence of different dysfunctional decision making networks in AN patients in the two decisional framework, confirming the importance of emotion and anxiety on decisional performance in AN. Since the cross sectional design of our study, further and longitudinal studies with recovered and at risk subjects are necessary to confirm our results

Performance analysis for wireless G (IEEE 802.11G) and wireless N (IEEE 802.11N) in outdoor environment

This paper described an analysis the different capabilities and limitation of both IEEE technologies that has been utilized for data transmission directed to mobile device. In this work, we have compared an IEEE 802.11/g/n outdoor environment to know what technology is better. The comparison consider on coverage area (mobility), throughput and measuring the interferences. The work presented here is to help the researchers to select the best technology depending of their deploying case, and investigate the best variant for outdoor. The tool used is Iperf software which is to measure the data transmission performance of IEEE 802.11n and IEEE 802.11g

Performance Analysis For Wireless G (IEEE 802.11 G) And Wireless N (IEEE 802.11 N) In Outdoor Environment

This paper described an analysis the different capabilities and limitation of both IEEE technologies that has been utilized for data transmission directed to mobile device. In this work, we have compared an IEEE 802.11/g/n outdoor environment to know what technology is better. the comparison consider on coverage area (mobility), through put and measuring the interferences. The work presented here is to help the researchers to select the best technology depending of their deploying case, and investigate the best variant for outdoor. The tool used is Iperf software which is to measure the data transmission performance of IEEE 802.11n and IEEE 802.11g