Impulsiveness, postprandial blood glucose and glucoregulation affect measures of behavioral flexibility

Behavioral flexibility (BF) performance is influenced by both psychological and physiological factors. Recent evidence suggests that impulsivity and blood glucose can affect executive function, of which BF is a subdomain. Here, we hypothesized that impulsivity, fasting blood glucose (FBG), glucose changes (i.e. glucoregulation) from postprandial blood glucose (PBG) following the intake of a 15g glucose beverage could account for variability in BF performance. The Stroop Color-Word Test and the Wisconsin Card Sorting Test (WCST) were used as measures of BF, and the Barratt Impulsiveness Scale (BIS-11) to quantify participants’ impulsivity. In Study 1, neither impulsivity nor FBG could predict performance on the Stroop or the WCST. In Study 2, we tested whether blood glucose levels following the intake of a sugary drink, and absolute changes in glucose levels following the intake of the glucose beverage could better predict BF. Results showed that impulsivity and the difference in blood glucose between time 1 (postprandial) and time 2, but not blood glucose levels at time 2 per se could account for variation in performance on the WCST but not on the Stroop task. More specifically, lower impulsivity scores on the BIS-11, and smaller differences in blood glucose levels from time 1 to time 2 predicted a decrease in the number of total and perseverative errors on the WCST. Our results show that measures of impulsivity and glucoregulation can be used to predict BF. Importantly our data extend the work on glucose and cognition to a clinically relevant domain of cognition

Deep brain stimulation affects conditioned and unconditioned anxiety in different brain areas.

Deep brain stimulation (DBS) of the nucleus accumbens (NAc) has proven to be an effective treatment for therapy refractory obsessive compulsive disorder. Clinical observations show that anxiety symptoms decrease rapidly following DBS. As in clinical studies different regions are targeted, it is of principal interest to understand which brain area is responsible for the anxiolytic effect and whether high-frequency stimulation of different areas differentially affect unconditioned (innate) and conditioned (learned) anxiety. In this study, we examined the effect of stimulation in five brain areas in rats (NAc core and shell, bed nucleus of the stria terminalis (BNST), internal capsule (IC) and the ventral medial caudate nucleus (CAU)). The elevated plus maze was used to test the effect of stimulation on unconditioned anxiety, the Vogel conflict test for conditioned anxiety, and an activity test for general locomotor behaviour. We found different anxiolytic effects of stimulation in the five target areas. Stimulation of the CAU decreased both conditioned and unconditioned anxiety, while stimulation of the IC uniquely reduced conditioned anxiety. Remarkably, neither the accumbens nor the BNST stimulation affected conditioned or unconditioned anxiety. Locomotor activity increased with NAc core stimulation but decreased with the BNST. These findings suggest that (1) DBS may have a differential effect on unconditioned and conditioned anxiety depending on the stimulation area, and that (2) stimulation of the IC exclusively reduces conditioned anxiety. This suggests that the anxiolytic effects of DBS seen in OCD patients may not be induced by stimulation of the NAc, but rather by the I

Evaluation and application of AHP, MAUT and ELECTRE III for infrastructure management

Infrastructure management renders a number of decision-making problems from assets condition inspections to maintenance planning and resources optimisation. Since management of infrastructure pertains to not only technical requirements but also to societal and economic developments, these decision problems have multiple and often conflicting objectives. Various methods of MCDA based on the decision theory and game theory are proposed to aid-in decision-making problems. Owing to the wide area of applications and extensive variation in MCDA methodology, the selection of appropriate MCDA method pertaining to the specific needs of infrastructure management and decision maker is a difficult task. In this paper, two synthesis-based methods (i.e. AHP and MAUT) and an outranking method (i.e. ELECTRE III) is applied on same maintenance decision making problem to evaluate them for their scalability, ease of use, risk consideration, and few other aspects. The results of evaluation suggest that a) without a computerised tool the scalability of these methods is tedious task b) only MAUT considers the risk attitude of a decision maker c) AHP and MAUT both require the data to be converted to definite scale for analysis, for instance, to Saaty scale of comparison and to utility functions respectively and d) unlike other two, ELECTRE works on preference structure and yields partial pre-orders. These aforementioned results are obtained by application of AHP, MAUT, and ELECTRE III on the maintenance planning decision problem of 22 road bridges from Netherlands road network. Despite the inherent methodology differences of these methods, the result of case study shows minor difference in ranking yielded by considered MCDA methods