RESUMO
Decision makers frequently encounter opportunities to pursue great gains-assuming they are willing to accept greater risks. Previous neuroimaging studies have shown that activity in the intraparietal sulcus (IPS) and the inferior frontal junction (IFJ) are associated with individual preferences for economic risk ("known unknowns," e.g., a 50% chance of winning $5) and ambiguity ("unknown unknowns," e.g., an unknown chance of winning $5), respectively. Whether processing in these regions causally enables risk-taking for individual decisions, however, remains unknown. To examine this question, we assessed the decision to engage in risk-taking after disrupting neural processing in the IPS and IFJ of healthy human participants using repetitive transcranial magnetic stimulation. While stimulation of the IFJ resulted in general slowing of decision times, disrupting neural processing within the IPS selectively suppressed risk-taking, biasing choices toward certain options featuring both lower risks and lower expected rewards. Our results are the first to demonstrate the necessity of intact IPS function for choosing uncertain outcomes when faced with calculable risks and rewards. Engagement of IPS during decision making may support a willingness to accept uncertain outcomes for a chance to obtain greater gains.
RESUMO
Philosophers and legal scholars have long theorized about how intentionality serves as a critical input for morality and culpability, but the emerging field of experimental philosophy has revealed a puzzling asymmetry. People judge actions leading to negative consequences as being more intentional than those leading to positive ones. The implications of this asymmetry remain unclear because there is no consensus regarding the underlying mechanism. Based on converging behavioral and neural evidence, we demonstrate that there is no single underlying mechanism. Instead, two distinct mechanisms together generate the asymmetry. Emotion drives ascriptions of intentionality for negative consequences, while the consideration of statistical norms leads to the denial of intentionality for positive consequences. We employ this novel two-mechanism model to illustrate that morality can paradoxically shape judgments of intentionality. This is consequential for mens rea in legal practice and arguments in moral philosophy pertaining to terror bombing, abortion, and euthanasia among others.
Assuntos
Julgamento/ética , Princípios Morais , Filosofia , Emoções/ética , Eutanásia/ética , Humanos , Proibitinas , Percepção Social , Terrorismo/éticaRESUMO
Individuals with autistic spectrum disorders exhibit distinct personality traits linked to attentional, social, and affective functions, and those traits are expressed with varying levels of severity in the neurotypical and subclinical population. Variation in autistic traits has been linked to reduced functional and structural connectivity (i.e., underconnectivity, or reduced synchrony) with neural networks modulated by attentional, social, and affective functions. Yet, it remains unclear whether reduced synchrony between these neural networks contributes to autistic traits. To investigate this issue, we used functional magnetic resonance imaging to record brain activation while neurotypical participants who varied in their subclinical scores on the Autism-Spectrum Quotient (AQ) viewed alternating blocks of social and nonsocial stimuli (i.e., images of faces and of landscape scenes). We used independent component analysis (ICA) combined with a spatiotemporal regression to quantify synchrony between neural networks. Our results indicated that decreased synchrony between the executive control network (ECN) and a face-scene network (FSN) predicted higher scores on the AQ. This relationship was not explained by individual differences in head motion, preferences for faces, or personality variables related to social cognition. Our findings build on clinical reports by demonstrating that reduced synchrony between distinct neural networks contributes to a range of subclinical autistic traits.
RESUMO
Impulsiveness is a personality trait that reflects an urge to act spontaneously, without thinking or planning ahead for the consequences of your actions. High impulsiveness is characteristic of a variety of problematic behaviors including attention deficit disorder, hyperactivity, excessive gambling, risk-taking, drug use, and alcoholism. Researchers studying attention and self-control often assess impulsiveness using personality questionnaires, notably the common Barratt Impulsiveness Scale version 11 (BIS-11; last revised in 1995). Advances in techniques for producing personality questionnaires over the last 20 years prompted us to revise and improve the BIS-11. We sought to make the revised scale shorter - so that it would be quicker to administer - and better matched to current behaviors. We analyzed responses from 1549 adults who took the BIS-11 questionnaire. Using a statistical technique called factor analysis, we eliminated 17 questions that did a poor job of measuring the three major types of impulsiveness identified by the scale: inattention, spontaneous action, and lack of planning. We constructed our ABbreviated Impulsiveness Scale (ABIS) using the remaining 13 questions. We showed that the ABIS performed well when administered to additional groups of 657 and 285 adults. Finally, we showed expected relationships between the ABIS and other personality measurements related to impulsiveness, and showed that the ABIS can help predict alcohol consumption. We present the ABIS as a useful and efficient tool for researchers interested in measuring impulsive personality.
RESUMO
Humans exhibit a remarkable capacity for flexible thought and action. Despite changing internal needs and external context, individuals maintain stable goals and pursue purposeful action. Functional neuroimaging research examining the neural underpinnings of such behavioral flexibility has progressed within several distinct traditions, as evident in the largely separate literatures on "cognitive control" and on "decision making." Both topics investigate the formulation of desires and intentions, the integration of knowledge and context, and the resolution of conflict and uncertainty. Additionally, each recognizes the fundamental role of the prefrontal cortex in supporting flexible selection of behavior. But despite this notable overlap, neuroimaging studies in cognitive control and decision making have exerted only limited influence on each other, in part due to differences in their theoretical and experimental groundings. Additionally, the precise organization of control processing within prefrontal cortex has remained unclear, fostering an acceptance of vague descriptions of decision making in terms of canonical cognitive control functions such as "inhibition" or "self-control." We suggest a unifying role for models of the hierarchical organization of action selection within prefrontal cortex. These models provide an important conceptual link between decision-making phenomena and cognitive-control processes, potentially facilitating cross-fertilization between these topics.