Positive risk taking and neural sensitivity to risky decision making in adolescence

This study examines associations between adolescents’ positive risk taking and neural activation during risky decision-making. Participants included 144 adolescents ages 13–16 years (M_age = 14.23; SD_age = 0.7) from diverse racial and ethnic groups. Participants self-reported their engagement in positive and negative risk taking. Additionally, participants played the Cups task during fMRI, where they chose between a safe choice (guaranteed earning of 15 cents) and a risky choice (varying probabilities of earning more than 15 cents). Using a risk-return framework, we examined adolescents’ sensitivity to both risks (safe versus risky) and returns (expected value, or potential reward as a function of its probability of occurring) at the behavioral and neural levels. All participants took more risks when the expected value of the choice was high. However, high positive risk taking was uniquely associated with dampened dmPFC tracking of expected value. Together, results show that adolescents’ positive risk taking is associated with neural activity during risky decision-making. Findings are among the first to identify brain-behavior correlations associated with positive risk taking during adolescence.     

Weighing up the benefits of work: behavioral and neural analyses of effort-related decision making.

How we decide whether a course of action is worth undertaking is largely unknown. Recently, neuroscientists have been turning to ecological approaches to address this issue, examining how animals evaluate the costs and benefits of different options. We present here evidence from rodents and monkeys that demonstrate the degree to which they take into account work and energetic requirements when deciding what responses to make. These calculations appear to be critically mediated by the anterior cingulate cortex (ACC) and mesolimbic dopamine (DA) pathways, with damage to either causing a bias towards options that are easily obtained but yield relatively smaller reward rather than alternatives that require more work but result in greater reward. The evaluation of such decisions appears to be carried out in systems independent of those involved in delay-discounting. We suggest that top-down signals from ACC to nucleus accumbens (NAc) and/or midbrain DA cells may be vital for overcoming effort-related response costs.     

Integrated Bayesian models of learning and decision making for saccadic eye movements

The neurophysiology of eye movements has been studied extensively, and several computational models have been proposed for decision-making processes that underlie the generation of eye movements towards a visual stimulus in a situation of uncertainty. One class of models, known as linear rise-to-threshold models, provides an economical, yet broadly applicable, explanation for the observed variability in the latency between the onset of a peripheral visual target and the saccade towards it. So far, however, these models do not account for the dynamics of learning across a sequence of stimuli, and they do not apply to situations in which subjects are exposed to events with conditional probabilities. In this methodological paper, we extend the class of linear rise-to-threshold models to address these limitations. Specifically, we reformulate previous models in terms of a generative, hierarchical model, by combining two separate sub-models that account for the interplay between learning of target locations across trials and the decision-making process within trials. We derive a maximum-likelihood scheme for parameter estimation as well as model comparison on the basis of log likelihood ratios. The utility of the integrated model is demonstrated by applying it to empirical saccade data acquired from three healthy subjects. Model comparison is used (i) to show that eye movements do not only reflect marginal but also conditional probabilities of target locations, and (ii) to reveal subject-specific learning profiles over trials. These individual learning profiles are sufficiently distinct that test samples can be successfully mapped onto the correct subject by a na?ve Bayes classifier. Altogether, our approach extends the class of linear rise-to-threshold models of saccadic decision making, overcomes some of their previous limitations, and enables statistical inference both about learning of target locations across trials and the decision-making process within trials.     

Impulsivity and decision making

The purpose of the present study was to explore the links among the four facets of impulsivity (urgency, lack of premeditation, lack of perseverance, and sensation seeking) proposed by and decision-making processes. Thirty undergraduate students completed a self-report questionnaire evaluating impulsivity as well as a task measuring decision-making processes, the Iowa Gambling Task. Zero-order correlations and multilevel analysis revealed that only lack of premeditation was specifically linked to disadvantageous decisions on the Gambling Task. This suggests that premeditation is related to decision making influenced by somatic (or emotional) markers.     

Sustained neural activity associated with cognitive control during temporally extended decision making

Decision making has both cognitive and affective components, but previous neuroimaging studies in this domain predominantly have focused on affect and reward. The current study examined a decision-making paradigm that placed strong demands on cognitive control processes by making reward payoffs contingent upon decision-making history. Payoffs were maximized by choosing the option that, paradoxically, was associated with a lower payoff on the immediate trial. Temporal integration requirements were manipulated by varying, across conditions, the window of previous trials over which the reward function was calculated. The cognitive demands of the task were hypothesized to engage neural systems responsible for integrating and actively maintaining actions and outcomes over time and the top-down biasing of response selection. Brain activation was monitored with functional magnetic resonance imaging (fMRI) using a mixed-blocked and event-related design to extract both transient and sustained neural responses. A network of brain regions commonly associated with cognitive control functions, including bilateral prefrontal cortex (PFC), bilateral parietal cortex, and medial frontal cortex, showed selectively sustained activation during the task. Increasing temporal integration demands led to a shift from transient to sustained activity in additional regions, including right hemisphere dorsolateral and frontopolar PFC. These results demonstrate the contribution of cognitive control mechanisms to temporally extended decision-making paradigms and highlight the benefits of decomposing activation responses into sustained and transient components.     

Risky decision making in Huntington's disease.

In the clinical setting, Huntington's disease is associated with problems in judgment and decision making, however, the extent of these problems and their association with clinical characteristics have not been assessed. Recently, a laboratory-based simulated gambling task has been used to quantify similar decision-making deficits in ventromedial frontal lobe damaged participants. We hypothesized that participants with Huntington's disease (HD) would show deficits on this gambling task. For this study, 14 HD participants were asked to make 100 selections from four decks of cards with varied payoffs in order to maximize winnings of play money. They were compared to 22 participants with Parkinson's disease (PD) and 33 healthy controls. After an initial period in which participants had to learn contingencies of the decks, the HD group made fewer advantageous selections than the PD and control groups. In HD, the number of advantageous selections in the gambling task was correlated with measures of memory and conceptualization but not disinhibition. Thus, people with HD may have had difficulties learning or remembering win/loss contingencies of the decks, or they may have failed to consistently take these into account in their card selections. These findings are consistent with current models of frontal-subcortical brain circuits and behavior.     

Governing boards and decision making

Governing boards should use a rational process to make decisions even though value judgments influence the process and data are not always available. A model for rational decision making is discussed and illustrated.     

Serotonin and decision making processes

Serotonin (5-HT) is an important player in decision making. Serotonergic antidepressant, anxiolytic and antipsychotic drugs are extensively used in the treatment of neuropsychiatric disorders characterized by impaired decision making, and exert both beneficial and harmful effects in patients. Detailed insight into the serotonergic mechanisms underlying decision making is needed to strengthen the first and weaken the latter. Although much remains to be done to achieve this, accumulating studies begin to deliver a coherent view. Thus, high central 5-HT levels are generally associated with improved reversal learning, improved attentional set shifting, decreased delay discounting, and increased response inhibition, but a failure to use outcome representations. Based on 5-HT's evolutionary role, I hypothesize that 5-HT integrates expected, or changes in, relevant sensory and emotional internal/external information, leading to vigilance behaviour affecting various decision making processes. 5-HT receptor subtypes play distinctive roles in decision making. 5-HT_2A agonists and 5-HT2c antagonists decrease compulsivity, whereas 5-HT_2A antagonists and 5-HT_2C agonists decrease impulsivity. 5-HT₆ antagonists univocally affect decision making processes.     

Contributions of the prefrontal cortex to the neural basis of human decision making

The neural basis of decision making has been an elusive concept largely due to the many subprocesses associated with it. Recent efforts involving neuroimaging, neuropsychological studies, and animal work indicate that the prefrontal cortex plays a central role in several of these subprocesses. The frontal lobes are involved in tasks ranging from making binary choices to making multi-attribute decisions that require explicit deliberation and integration of diverse sources of information. In categorizing different aspects of decision making, a division of the prefrontal cortex into three primary regions is proposed. (1) The orbitofrontal and ventromedial areas are most relevant to deciding based on reward values and contribute affective information regarding decision attributes and options. (2) Dorsolateral prefrontal cortex is critical in making decisions that call for the consideration of multiple sources of information, and may recruit separable areas when making well defined versus poorly defined decisions. (3) The anterior and ventral cingulate cortex appear especially relevant in sorting among conflicting options, as well as signaling outcome-relevant information. This topic is broadly relevant to cognitive neuroscience as a discipline, as it generally comprises several aspects of cognition and may involve numerous brain regions depending on the situation. The review concludes with a summary of how these regions may interact in deciding and possible future research directions for the field.     

Perfusion abnormalities and decision making in cocaine dependence.

BACKGROUND: Previous studies have shown that cocaine abusers have cerebral perfusion deficits that may diminish cognitive functioning. This study examined whether cocaine-dependent patients have perfusion abnormalities associated with poor decision-making ability as measured by the Iowa Gambling Task (IGT). METHODS: Seventeen abstinent cocaine-dependent patients were administered the IGT after completion of resting 99mTc-HMPAO single-photon emission computed tomography (SPECT). RESULTS: Better IGT performance was negatively correlated with perfusion within the anterior cingulate gyrus, middle frontal gyrus, medial frontal gyrus, and superior frontal gyrus. The time to complete card selections was positively correlated with the severity of impairment. CONCLUSIONS: Resting hyperperfusion in brain regions previously implicated in decision making and response inhibition was associated with worse IGT scores. Impaired performance was related to a greater amount of time taken for card selections, suggesting that reduced ability was due to cognitive factors other than an impulsive response pattern.     

The relationship between family structure and process variables and adolescent decision making

This study examined the relationship between family structural and process variables and adolescent participation in family decisions and vigilant decision making. Data were obtained from a survey sample of 585 adolescents aged 12-18 years living in Adelaide, South Australia. Adolescents from one-parent families participated in a greater number of family decisions than those from two-parent families. Adolescents from families adaptable in allocating roles and setting rules participated in more family decisions than those from low adaptable families. Family socio-economic status was significantly linked to the adolescent's self reported vigilance. High family cohesion, good parent-adolescent communication and sound parental conflict resolution skills were also significantly related to adolescents' vigilant decision making, testifying to the importance of family environment in the socialization of adolescents for decision making.     

A metacognitive analysis of decision making in adolescence.

Samples of 43 early (CA = 13 years) and 41 middle (CA = 15 years) adolescents were compared on three categories of metacognitive knowledge as they relate to decision making--person knowledge, task knowledge and strategy knowledge. Metacognitive knowledge was assessed using a 19-item questionnaire. Consistent with our hypothesis, middle adolescents showed significantly greater metacognitive knowledge than early adolescents on all three scales. Self-reported decision making style (using the Flinders Adolescent Decision Making Questionnaire) and decision making performance on a hypothetical scenario were also measured. Middle adolescents reported a more competent decision making style than early adolescents, while group differences on the scenario were not found. Adolescents completing the scenario scored significantly higher on all measures of decision making metacognition. Significant correlations were found between metacognitive knowledge of decision making, self-reported decision making style and performance on the decision scenario task. By middle adolescence understanding of what is involved in the activity of decision making is well developed. This growth in understanding, accompanied by changes in social domains, plays a part in decision execution and style.     

Neuropsychiatric decision making: designing nonbinary diagnostic tests.

Most diagnostic tests used in medicine, science, and technology are nonbinary: they are based on quantification of a variable that has a range of possible values. In this article, the authors describe how such tests are designed and characterized. They shall use the concepts developed here in future articles that describe how diagnostic techniques are operationalized for clinical settings.     

The cerebellum and decision making under uncertainty

This study aimed to identify the neural basis of probabilistic reasoning, a type of inductive inference that aids decision making under conditions of uncertainty. Eight normal subjects performed two separate two-alternative-choice tasks (the balls in a bottle and personality survey tasks) while undergoing functional magnetic resonance imaging (fMRI). The experimental conditions within each task were chosen so that they differed only in their requirement to make a decision under conditions of uncertainty (probabilistic reasoning and frequency determination required) or under conditions of certainty (frequency determination required). The same visual stimuli and motor responses were used in the experimental conditions. We provide evidence that the neo-cerebellum, in conjunction with the premotor cortex, inferior parietal lobule and medial occipital cortex, mediates the probabilistic inferences that guide decision making under uncertainty. We hypothesise that the neo-cerebellum constructs internal working models of uncertain events in the external world, and that such probabilistic models subserve the predictive capacity central to induction.     

Information and decision making in human services

The author discusses organizational decision making and the way administrators typically obtain and use information in their daily work. The informal processes of information collection and utilization are stressed.