An event-related fMRI study on risk taking by healthy individuals of high or low impulsiveness

Abnormal Brain Circuits Characterize Borderline Personality and Mediate the Relationship between Childhood Traumas and Symptoms: A mCCA+jICA and Random Forest Approach

Borderline personality disorder (BPD) is a severe personality disorder whose neural bases are still unclear. Indeed, previous studies reported inconsistent findings concerning alterations in cortical and subcortical areas. In the present study, we applied for the first time a combination of an unsupervised machine learning approach known as multimodal canonical correlation analysis plus joint independent component analysis (mCCA+jICA), in combination with a supervised machine learning approach known as random forest, to possibly find covarying gray matter and white matter (GM-WM) circuits that separate BPD from controls and that are also predictive of this diagnosis. The first analysis was used to decompose the brain into independent circuits of covarying grey and white matter concentrations. The second method was used to develop a predictive model able to correctly classify new unobserved BPD cases based on one or more circuits derived from the first analysis. To this aim, we analyzed the structural images of patients with BPD and matched healthy controls (HCs). The results showed that two GM-WM covarying circuits, including basal ganglia, amygdala, and portions of the temporal lobes and of the orbitofrontal cortex, correctly classified BPD against HC. Notably, these circuits are affected by specific child traumatic experiences (emotional and physical neglect, and physical abuse) and predict symptoms severity in the interpersonal and impulsivity domains. These results support that BPD is characterized by anomalies in both GM and WM circuits related to early traumatic experiences and specific symptoms.

Are you more impulsive with age? Examining age, marital status, and gender on cognitive ageing

Understanding non-pathological cognitive aging processes remains a public health goal and research priority. Age-associated cognitive aging is a normal human process, however, individual differences may aid in the mitigation of cognitive aging. Assessing the role of certain protective factors (i.e., age, marital status, and gender) that influence age-related cognitive aging is imperative to slow down the progression of unwarranted cognitive aging. Participants aged over 18 (N = 123; 97 females and 26 males) recruited from Sydney, New South Wales, and Gold Coast, Queensland, completed an online neuropsychological test battery with computer-administered tasks, assessing impulsivity and working memory, which were entered as dependent variables. A 3(Age Group: 18-27 years; 28-61 years; 62+ years) x2(Marital Status: married; single) x2(Gender: male; female) Multivariate Analysis of Covariance (MANCOVA) design was used to examine the relationship between age, marital status, and gender (entered as independent variables) on cognitive aging. Participants' total scores from psychometrically sound measures assessing depressive symptomology, personal wellbeing, resilience, and social network engagement, were entered as covariates. No significant effects were found from the independent variables included in the MANCOVA. A significant covariate effect for resilience and depressive symptomology on impulsivity was found. A multiple regression analysis was performed on the significant covariates, and revealed increased resilience and depressive symptomology to significantly predict greater impulsivity.

The protective effect of daytime sleep on planning and risk-related decision-making in emerging adults

We assessed the effect of a daytime sleep opportunity on planning and risk-related decision-making in emerging adults using multiple neurobehavioral assessments. A total of 136 healthy emerging adults (20.0 ± 1.5 years), 65% female, performed the Risky-Gains Task and the Tower of London test twice. Between these assessments, they were randomized to either have a sleep opportunity monitored by polysomnography (Sleep group, n = 101) or to stay awake (Wake group, n = 35). During Test 2, in comparison to the Sleep group, the Wake group showed increased sleepiness, worse planning ability and more decrease in reaction times when selecting risky choices. Changes in Tower of London test steps used and Risky-Gains Task response time correlated with the number of central and frontal fast sleep spindles, respectively. These results indicate that among emerging adults who commonly have poor sleep patterns, a daytime sleep opportunity was related to better planning ability, better psychomotor vigilance and stable response speeds in risk-related decision-making. Changes in planning and risk-related decision-making correlated with the number of sleep spindles during the nap, supporting a specific role for sleep in modulating planning and potentially other higher-order cognitive functions.

The coupling of short sleep duration and high sleep need predicts riskier decision making

Objective: To examine how risk-related decision making might be associated with habitual sleep variables, including sleep variability, sleep duration and perceived sleep need in young adults cross-sectionally and longitudinally. Design: 166 participants completed a 7-day protocol with sleep and risk-related decision-making measures at baseline (T1) and 12 months later (T2). Results: Habitual short sleep duration (averaging < 6 h nightly) was identified in 11.0% in our sample. After controlling for baseline demographic factors and risk-taking measures, self-reported sleep need at T1 interacted with habitual short sleep in predicting risk taking at follow-up (F_8,139=9.575, adjusted R²=.431, p<.001). T1 greater perceived sleep need predicted more risk taking among short sleepers, but decreased risk taking among normal sleepers at T2. Variable sleep timing was cross-sectionally correlated with making more Risky choices at baseline and fewer Safe choices after loss at follow up. Conclusions: Young adults with variable sleep timing and those with short sleep duration coupled with high perceived sleep need were more likely to take risks. The moderating effects of perceived sleep need suggest that individual differences may alter the impact of sleep loss and hence should be measured and accounted for in future studies.

Altered spontaneous brain activity in adolescent boys with pure conduct disorder revealed by regional homogeneity analysis

Functional magnetic resonance imaging (fMRI) studies have revealed abnormal neural activity in several brain regions of adolescents with conduct disorder (CD) performing various tasks. However, little is known about the spontaneous neural activity in people with CD in a resting state. The aims of this study were to investigate CD-associated regional activity abnormalities and to explore the relationship between behavioral impulsivity and regional activity abnormalities. Resting-state fMRI (rs-fMRI) scans were administered to 28 adolescents with CD and 28 age-, gender-, and IQ-matched healthy controls (HCs). The rs-fMRI data were subjected to regional homogeneity (ReHo) analysis. ReHo can demonstrate the temporal synchrony of regional blood oxygen level-dependent signals and reflect the coordination of local neuronal activity facilitating similar goals or representations. Compared to HCs, the CD group showed increased ReHo bilaterally in the insula as well as decreased ReHo in the right inferior parietal lobule, right middle temporal gyrus and right fusiform gyrus, left anterior cerebellum anterior, and right posterior cerebellum. In the CD group, mean ReHo values in the left and the right insula correlated positively with Barratt Impulsivity Scale (BIS) total scores. The results suggest that CD is associated with abnormal intrinsic brain activity, mainly in the cerebellum and temporal-parietal-limbic cortices, regions that are related to emotional and cognitive processing. BIS scores in adolescents with CD may reflect severity of abnormal neuronal synchronization in the insula.

Different roads to the same destination - The impact of impulsivity on decision-making processes under risk within a rewarding context in a healthy male sample

The results of research about the influences of impulsivity on decision-making in situations of risk have been inconsistent. In this study, we used functional magnetic resonance imaging to examine the neural correlates of decision-making under risk in 12 impulsive, as defined by the Barratt Impulsiveness Scale-11, and 13 normal men. Although both groups showed similar decision-making behavior, neural activation regarding decision-making processes differed significantly. Impulsive persons revealed stronger activation in the (ventro-) medial prefrontal cortex and less deactivation of the orbitofrontal cortex while playing for potential gains. These brain regions might be associated with the emotional components of decision-making processes. Significant differences in brain areas linked to cognitive decision-making components were not found. This activation pattern might be seen as an indication for a hypersensitivity to rewarding cues in impulsive persons and might be linked to the propensity for inappropriate risk-taking behavior in persons with more extreme impulsivity levels, especially in situations in which they have a strong emotional involvement in the decision process.

Nowicki D, Deshpande G, F. Lusch R. Converting knowledge into value

Purpose

– The purpose of this paper is to describe the conversion of knowledge into value by examining the confluence of service-dominant logic (S-D logic), supply chain management (SCM), human resource management (HRM), and neuroeconomics. S-D logic suggests that knowledge is the raw material of value creation. SCM provides an organized foundation to study the conversion of raw materials into value. HRM recognizes the centrality of human decisions in the process of converting knowledge into value. Neuroscience gives insight into the efficiency and effectiveness of the human decisions processes. Global SCM provides more than markets and raw materials – global SCM provides the human resources central to value creation.

Design/methodology/approach

– This paper combines literature review with interviews from members of supply chain teams engaged in performance-based logistics (PBL) to develop a model of the S-D logic knowledge conversion process.

Findings

– The model describes individual-based decision constructs managers can expect to face as they convert knowledge, from a global supply chain team, into value. The model relates the decision maker mindset, based in neuroscience principals, to the efficiency of the knowledge conversion process. These principals are extended to suggest how managers can modulate human resource processes to improve the efficiency of economic exchange and increase supply chain resiliency.

Research limitations/implications

– This paper provides theoretical and practical insight into how differences in culture, neuronal predisposition, and genetics may influence managerial decisions. These findings provide a mechanism that researchers and managers may take to expand the boundaries of HRM in a global supply chain.

Originality/value

– This work uses a foundation of SCM research to explain efficient conversion in a knowledge-based economy. This perspective demonstrates the criticality of global HRM mindsets and decision processes necessary to achieve competitive advantage in a knowledge-based economy. This provides a context for the study and improvement of neuroeconomic efficiency of firms.

The neural correlates of risk propensity in males and females using resting-state fMRI

Men are more risk prone than women, but the underlying basis remains unclear. To investigate this question, we developed a trait-like measure of risk propensity which we correlated with resting-state functional connectivity to identify sex differences. Specifically, we used short- and long-range functional connectivity densities to identify associated brain regions and examined their functional connectivities in resting-state functional magnetic resonance imaging (fMRI) data collected from a large sample of healthy young volunteers. We found that men had a higher level of general risk propensity (GRP) than women. At the neural level, although they shared a common neural correlate of GRP in a network centered at the right inferior frontal gyrus, men and women differed in a network centered at the right secondary somatosensory cortex, which included the bilateral dorsal anterior/middle insular cortices and the dorsal anterior cingulate cortex. In addition, men and women differed in a local network centered at the left inferior orbitofrontal cortex. Most of the regions identified by this resting-state fMRI study have been previously implicated in risk processing when people make risky decisions. This study provides a new perspective on the brain-behavioral relationships in risky decision making and contributes to our understanding of sex differences in risk propensity.

Age-related changes in insula cortical thickness and impulsivity: significance for emotional development and decision-making

Insula function has been associated with emotional regulation, adjusting to changing outcomes under risk, reward and loss anticipation, discounting of future rewards, and self-rated impulsivity. The role of the insula in these processes may be fundamentally related to prospective thinking, a trait that increases with age. There is evidence that insular cortical thickness shows age related decreases that parallel age related increases in future orientation and planning. We tested the hypothesis that nonplanning decreases with age and that insula thickness is related to both age and nonplanning impulsivity. Fifty-nine male and female participants, ranging in age from 10 to 22 years old, underwent structural magnetic resonance imaging (MRI) procedures and were assessed using the Barratt Impulsiveness Scale (BIS). We observed that anterior insula thickness and nonplanning impulsivity show an inverse relationship with age and that there is a significant positive linear relationship between anterior insula thickness and nonplanning.

Reduced insular volume in attention deficit hyperactivity disorder

The aim of this study was to evaluate whether structural differences in the insula and anterior cingulate cortex (ACC), two critical areas of the "salience network," co-exist in adolescents with attention deficit hyperactivity disorder (ADHD) compared with healthy controls (HC). In addition we aimed to determine if structural changes within these regions correlate with attention and inhibitory function. Nineteen adolescents with ADHD and 25 HC received MRI scans on a 3T magnet. Morphometric analysis was performed with FreeSurfer. Youths with ADHD were found to have a bilateral reduction in anterior insular (AIC) gray matter volumes compared to HC. Furthermore, the left AIC was found to positively correlate with oppositional symptoms, while the right AIC was found to associate with both attention problems and inhibition. To our knowledge this is the first report of a bilateral reduction in AIC volumes in ADHD. Our findings suggest a role for the insula in modulating attention and inhibitory capacity in ADHD.

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.

Impulsivity and Parkinson's disease: more than just disinhibition

In the last few years it has become clear that impulsivity is a complex behaviour composed of different domains and dependent on different neural networks. The proposed pathogenetic mechanisms for the emergence of impulsivity disorders in Parkinson's Disease (PD) can be broadly separated into three potentially interacting processes: the contribution of premorbid susceptibility to impulsivity, the contribution of the disease itself to the behaviour and the potential contribution of therapeutic agents. Growing evidence suggests that dopamine and the subthalamic nucleus are playing a certain role in the pathophysiology of different aspects of impulsivity. In this review, we summarise the main concepts defining various components of impulsivity both in healthy subjects and patients affected by PD.

Cortical thickness correlates with impulsiveness in healthy adults

BACKGROUND

Impulsiveness is a central domain of human personality and of relevance for the development of substance use and certain psychiatric disorders. This study investigates whether there are overlapping as well as distinct structural cerebral correlates of attentional, motor and nonplanning impulsiveness in healthy adults.

METHODS

High-resolution magnetic resonance scans were acquired in 32 healthy adults to model the gray-white and gray-cerebrospinal fluid borders for each individual cortex and to compute the distance of these surfaces as a measure of cortical thickness (CT). Associations between CT and the dimensions of impulsiveness (Barratt-Impulsiveness-Scale 11, BIS) were identified in entire cortex analyses.

RESULTS

We observed a significant negative correlation between left middle frontal gyrus (MFG) CT and the attention BIS score (FDR p<.05), motor, nonplanning and total BIS score (each p<0.001 uncorrected). In addition, CT of the orbitofrontal (OFC) and superior frontal gyrus (SFG) were inversely correlated (p<0.001 uncorrected) with BIS total and motor score. Among other negative associations only one positive correlation (right inferior temporal with nonplanning score, p<0.001 uncorrected) was found.

CONCLUSIONS

The MFG is crucial for top-down control, executive and attentional processes. The MFG together with the OFC and SFG appears to be part of brain structures, which have previously been shown to mediate behavioral inhibition, well-planned action and attention, which are core facets of impulsiveness as measured with the Barratt-Impulsiveness-Scale.

Your resting brain CAREs about your risky behavior

BACKGROUND

Research on the neural correlates of risk-related behaviors and personality traits has provided insight into mechanisms underlying both normal and pathological decision-making. Task-based neuroimaging studies implicate a distributed network of brain regions in risky decision-making. What remains to be understood are the interactions between these regions and their relation to individual differences in personality variables associated with real-world risk-taking.

METHODOLOGY/PRINCIPAL FINDINGS

We employed resting state functional magnetic resonance imaging (R-fMRI) and resting state functional connectivity (RSFC) methods to investigate differences in the brain's intrinsic functional architecture associated with beliefs about the consequences of risky behavior. We obtained an individual measure of expected benefit from engaging in risky behavior, indicating a risk seeking or risk-averse personality, for each of 21 participants from whom we also collected a series of R-fMRI scans. The expected benefit scores were entered in statistical models assessing the RSFC of brain regions consistently implicated in both the evaluation of risk and reward, and cognitive control (i.e., orbitofrontal cortex, nucleus accumbens, lateral prefrontal cortex, dorsal anterior cingulate). We specifically focused on significant brain-behavior relationships that were stable across R-fMRI scans collected one year apart. Two stable expected benefit-RSFC relationships were observed: decreased expected benefit (increased risk-aversion) was associated with 1) stronger positive functional connectivity between right inferior frontal gyrus (IFG) and right insula, and 2) weaker negative functional connectivity between left nucleus accumbens and right parieto-occipital cortex.

CONCLUSIONS/SIGNIFICANCE

Task-based activation in the IFG and insula has been associated with risk-aversion, while activation in the nucleus accumbens and parietal cortex has been associated with both risk seeking and risk-averse tendencies. Our results suggest that individual differences in attitudes toward risk-taking are reflected in the brain's functional architecture and may have implications for engaging in real-world risky behaviors.

Cognitive impulsivity in Parkinson's disease patients: assessment and pathophysiology

Impulsivity may be induced by therapeutic interventions (dopamine replacement therapies and sub-thalamic nucleus (STN) stimulation) in patients with Parkinson's disease (PD). The present review has two goals. First, to describe the most frequently encountered facets of cognitive impulsivity and to stress the links between cognitive impulsivity and aspects such as reward-related decision making, risk-taking, and time-processing in healthy population. The most widely used related cognitive impulsivity paradigms are presented. Second, to review the results of studies on cognitive impulsivity in healthy volunteers and in patients with PD, the latter support the applicability and clinical relevance of this construct in PD population. Data show that PD treatments may favor impulsivity via different mechanisms. Suggestions on the roles of dopamine and STN in the pathophysiology of cognitive impulsivity are proposed.

Neural correlates of traditional Chinese medicine induced advantageous risk-taking decision making

This fMRI study examined the neural correlates of the observed improvement in advantageous risk-taking behavior, as measured by the number of adjusted pumps in the Balloon Analogue Risk Task (BART), following a 60-day course of a Traditional Chinese Medicine (TCM) recipe, specifically designed to regulate impulsiveness in order to modulate risk-taking behavior. The 14 participants recruited for this study were randomly assigned to the experimental and control groups and the TCM recipe (Panax, 520 mg; Astragalus membranaceous Bunge, 520 mg; Masnetitum, 840 mg; Ostrea gigas Thumb, 470 mg; Thinleaf Milkwort Root Radix Polygalae, 450 mg; and Os Draconis, 470 mg) was administered, as a diet supplement, to the seven participants in the experimental group. The neural activity of the two groups was monitored by a 3T MRI scanner, before and after the 60-day treatment. Associated with the improved advantageous risk-taking behavior seen in the experimental group, significantly stronger blood oxygenation level dependent (BOLD) responses were observed in the bilateral dorsolateral prefrontal cortex (DLPFC), left putamen, left thalamus, right insula, and right anterior cingulate cortex (ACC), regions which have previously been reported as being involved in risk-taking decision making. The effect of the TCM in improving advantageous risk-taking decision making appears to have been related to the enhanced efficiency of the cognitive affective system, the PFC-ACC-insula-striatum network, which functions to inhibit impulsiveness, to sensitize reward-related information, and to allow the opportunity, during risk estimation, to evaluate potential gains and losses. The findings of this study suggest that interventions acting on factors modulating risk-taking decision making could have a beneficial effect in terms of optimizing risk-taking behavior.

Neural correlates of speeded as compared with delayed responses in a stop signal task: an indirect analog of risk taking and association with an anxiety trait

The stop signal task (SST) is widely used to explore neural processes involved in cognitive control. By randomly intermixing stop and go trials and imposing on participants to respond quickly to the go but not the stop signal, the SST also introduces an indirect element of risk, which participants may avert by slowing down or ignore by responding "as usual," during go trials. This "risk-taking" component of the SST has to our knowledge never been investigated. The current study took advantage of variability of go trial reaction time (RT) and compared the post-go go trials that showed a decrease in RT (risk-taking decision) and those post-go go trials that showed an increase in RT ("risk-aversive" decision) in 33 healthy individuals who underwent functional magnetic resonance imaging during the SST. This contrast revealed robust activation in bilateral visual cortices as well as left inferior parietal and posterior cingulate cortices, amygdala, and middle frontal gyrus (P < 0.05, family-wise error [FWE] corrected). Furthermore, we observed that the magnitude of amygdala activity is positively correlated with trait anxiety of the participants. These results thus delineated, for the first time, a neural analog of risk taking during stop signal performance, highlighting a novel aspect and broadening the utility of this behavioral paradigm.