Personality and psychopathology: In defense of a practical path toward integrating psychometric and biological approaches to advance a comprehensive model.

Personality and psychopathology each reflect patterns of internal experience and outward behavior that differ between people and affect functioning. Drawing strict distinctions between the two concepts is not only difficult, but it may prove unnecessary for advancing an integrated model of psychological experiences associated with mental illness. We argue that developing such a model will be critical for improving treatment outcomes, and we discuss a practical path forward. Proponents of psychometric approaches to developing models of psychological experience focus on observable phenotypes and utilize statistical methods to describe patterns of covariation among a broad range of symptoms and dispositions. Advocates of biologically based approaches emphasize neuroscientific tools for identifying abnormalities in brain function that give rise to an individual's experience. There is substantial evidence that measures of personality and measures of symptoms capture nonoverlapping, clinically important information for understanding how and for whom treatments for mental illness work. In this article, we highlight the importance of combining psychometric and neurobiological approaches in order to understand which features of an individual those measures reflect, which aspects of neurobiology generate and maintain those features, how they relate to each other, and critically, how best to alter them to reduce distress and dysfunction.

Is brain response to food rewards related to overeating? A test of the reward surfeit model of overeating in children.

The reward surfeit model of overeating suggests that heightened brain response to rewards contributes to overeating and subsequent weight gain. However, previous studies have not tested whether brain response to reward is associated with food intake, particularly during childhood, a period of dynamic development in reward and inhibitory control neurocircuitry. We conducted functional magnetic resonance imaging (fMRI) with 7-11-year-old children (n = 59; healthy weight, n = 31; overweight, n = 28; 54% female) while they played a modified card-guessing paradigm to examine blood-oxygen-level-dependent (BOLD) response to anticipating and winning rewards (food, money, neutral). Food intake was assessed at three separate meals that measured different facets of eating behavior: 1) typical consumption (baseline), 2) overindulgence (palatable buffet), and 3) eating in the absence of hunger (EAH). A priori regions of interest included regions implicated in both reward processing and inhibitory control. Multiple stepwise regressions were conducted to examine the relationship between intake and BOLD response to rewards. Corrected results showed that a greater BOLD response in the medial prefrontal cortex for anticipating food compared to money positively correlated with how much children ate at the baseline and palatable buffet meals. BOLD response in the dorsolateral prefrontal cortex for winning food compared to money was positively correlated with intake at the palatable buffet meal and EAH. All aforementioned relationships were independent of child weight status. Findings support the reward surfeit model by showing that increased brain response to food compared to money rewards positively correlates with laboratory measures of food intake in children.

Reduced Influence of Monetary Incentives on Go/NoGo Performance During Smoking Abstinence.

INTRODUCTION: Smokers may experience decreased sensitivity to nondrug incentives during acute smoking deprivation. This decreased sensitivity may undermine attempts to encourage continued abstinence by enhancing cognitive processes through the use of monetary incentives. This study assessed whether the capacity for monetary incentives to enhance cognitive performance was compromised in nicotine-deprived smokers. METHOD: Eighteen smokers performed an incentivized Go/NoGo task on 2 occasions, once after smoking as usual prior to the session, and once after undergoing 12-hr abstinence. Participants could earn up to $5.00 ($2.50 per session) based on their performance on reward blocks of the Go/NoGo task. RESULTS: Performance was significantly more accurate on incentivized NoGo, frequent-Go, and infrequent-Go trials relative to neutral trials during the smoke as usual session. Participants also produced fewer premature, impulsive responses on rewarded versus neutral blocks during the smoke as usual session. No significant difference between reward and neutral blocks was observed on any of the 4 performance indices during the abstinent session. CONCLUSIONS: The ability for monetary incentives to enhance inhibitory control may be compromised during acute abstinence in smokers. These findings may have implications for contingency management treatment programs which are thought to promote continued abstinence partly by facilitating the allocation of cognitive resources to processes that encourage continued abstinence by increasing the value associated with continued abstinence.

Decision-Making Processes Related to Perseveration Are Indirectly Associated With Weight Status in Children Through Laboratory-Assessed Energy Intake.

Decision-making contributes to what and how much we consume, and deficits in decision-making have been associated with increased weight status in children. Nevertheless, the relationships between cognitive and affective processes underlying decision-making (i.e., decision-making processes) and laboratory food intake are unclear. We used data from a four-session, within-subjects laboratory study to investigate the relationships between decision-making processes, food intake, and weight status in 70 children 7-to-11-years-old. Decision-making was assessed with the Hungry Donkey Task (HDT), a child-friendly task where children make selections with unknown reward outcomes. Food intake was measured with three paradigms: (1) a standard ad libitum meal, (2) an eating in the absence of hunger (EAH) protocol, and (3) a palatable buffet meal. Individual differences related to decision-making processes during the HDT were quantified with a reinforcement learning model. Path analyses were used to test whether decision-making processes that contribute to children's (a) expected value of a choice and (b) tendency to perseverate (i.e., repeatedly make the same choice) were indirectly associated with weight status through their effects on intake (kcal). Results revealed that increases in the tendency to perseverate after a gain outcome were positively associated with intake at all three paradigms and indirectly associated with higher weight status through intake at both the standard and buffet meals. Increases in the tendency to perseverate after a loss outcome were positively associated with EAH, but only in children whose tendency to perseverate persistedacross trials. Results suggest that decision-making processes that shape children's tendencies to repeat a behavior (i.e., perseverate) are related to laboratory energy intake across multiple eating paradigms. Children who are more likely to repeat a choice after a positive outcome have a tendency to eat more at laboratory meals. If this generalizes to contexts outside the laboratory, these children may be susceptible to obesity. By using a reinforcement learning model not previously applied to the study of eating behaviors, this study elucidated potential determinants of excess energy intake in children, which may be useful for the development of childhood obesity interventions.

Individual differences in the influence of taste and health impact successful dietary self-control: A mouse tracking food choice study in children.

In order to improve dietary quality among children, there is a need to understand how they make decisions about what foods to eat. This study used a mouse tracking food choice task to better understand how attributes such as health and taste contribute to food decisions among 70 children aged 7-to-11 years old. Children rated health, taste, and desire to eat for 76 common foods that varied in energy density and then used a computer mouse to select which of two presented foods they would like to eat. The presented food pairs were based on children's own ratings of taste and health so that some trials required self-control to choose the healthier option (i.e., healthy/not tasty paired with unhealthy/tasty). Children's body mass index (BMI) percentile was not associated with number of healthy choices. To examine mouse trajectories, we replicated previous analytic techniques and applied a novel technique, time-varying effects modeling (TVEM). Results showed that desire to eat impacted food decision-making sooner than taste and health during trials that required self-control, with TVEM showing that early discounting of desire to eat enabled healthier choices. However, these temporal dynamics varied by age, BMI percentile, and overall self-control performance in the task. When the less healthy food was chosen (i.e., self-control failure), older children and children with better overall self-control were more influenced by taste and desire to eat. However, children with higher BMI percentiles showed stronger discounting (i.e., negative influence) of taste when choosing the healthier food. Together this highlights how the influence of hedonic food attributes on food decision-making varies by individual child-level characteristics. Understanding individual differences in the cognitive processes that support healthy food choices in children may help identify targets for interventions aimed at improving child nutrition.

A Novel Hierarchical LATER Process Model: Evaluating Latent Sources of Variation in Reaction Times of Adult Daily Smokers.

Reaction time data from cognitive tasks continue to be a key way to assess decision-making in various contexts to better understand addiction. The goal of this paper is twofold: to introduce a nuanced modeling approach for reaction time data and to demonstrate the novel insights it can provide into the decision processes of nicotine-dependent individuals in different contexts. We focus on the Linear Approach to Threshold with Ergodic Rate (LATER) model, which is a cognitive process model that describes reaction time data in terms of two distinct aspects of cognitive functioning: speed of information accumulation ("accretion") and threshold amount of information needed prior to execution ("caution"). We introduce a novel hierarchical extension to the LATER model to simultaneously account for differences across persons and experimental conditions, both in the accretion and caution parameters. This approach allows for the inclusion of person-specific predictor variables to explain between-person variation in terms of accretion and caution together with condition-specific predictors to model experimental condition manipulations. To highlight the usefulness of this model, we analyze reaction time data from a study on adult daily cigarette smokers. Participants performed a monetary incentivized Go/No-Go task during two testing sessions, once while following their typical smoking patterns and again following 12 h of verified smoking abstinence. Our main results suggest that regardless of trial type, smokers in a period of abstinence have faster accretion rates, and lower caution thresholds relative to smoking as usual.