A computational model of fractionated conflict-control mechanisms in task-switching

A feature of human cognition is the ability to monitor and adjust one's own behavior under changing circumstances. A dynamic balance between controlled and rapid responding is needed to adapt to a fluctuating environment. We suggest that cognitive control may include, among other things, two distinct processes. Incongruent stimuli may drive top-down facilitation of task-relevant responses to bias performance toward exploitation vs. exploration. Task or response switches may generally slow responses to bias toward accuracy vs. speed and exploration vs. exploitation. Behavioral results from a task switching study demonstrate these two distinct processes as revealed by higher-order sequential effects. A computational model implements the two conflict-control mechanisms, which allow it to capture many complex and novel sequential effects. Lesion studies with the model demonstrate that the model is unable to capture these effects without the conflict-control loops and show how each monitoring component modulates cognitive control. The results suggest numerous testable predictions regarding the neural substrates of cognitive control.     

Ghosts, UFOs, and magic: positive affect and the experiential system

Three studies examined the potential interactions of the experiential system and positive affect (PA) in predicting superstitious beliefs and sympathetic magic. In Study 1, experientiality and induced positive mood interacted to predict the emergence of belief in videos purporting to show unidentified flying objects or ghosts. In Study 2, naturally occurring PA interacted with experientiality to predict susceptibility to sympathetic magic, specifically difficulty in throwing darts at a picture of a baby (demonstrating the law of similarity). In Study 3, induced mood interacted with experientiality to predict sitting farther away from, and expressing less liking for, a partner who had stepped in excrement (demonstrating the law of contagion). Results are interpreted as indicating that PA promotes experiential processing. Implications for the psychology of nonrational beliefs and behaviors are discussed.     

Why did the white bear return? Obsessive-compulsive symptoms and attributions for unsuccessful thought suppression

The current study examined the nature and consequences of attributions about unsuccessful thought suppression. Undergraduate students with either high (n=67) or low (n=59) levels of obsessive–compulsive symptoms rated attributions to explain their unsuccessful thought suppression attempts. We expected that self-blaming attributions and attributions ascribing importance to unwanted thoughts would predict more distress and greater recurrence of thoughts during time spent monitoring or suppressing unwanted thoughts. Further, we expected that these attributions would mediate the relationship between obsessive–compulsive symptom levels and the negative thought suppression outcomes (distress and thought recurrence). Structural equation models largely confirmed the hypotheses, suggesting that attributions may be an important factor in explaining the consequences of thought suppression. Implications are discussed for cognitive theories of obsessive–compulsive disorder and thought suppression.     

From mere coincidences to meaningful discoveries

People's reactions to coincidences are often cited as an illustration of the irrationality of human reasoning about chance. We argue that coincidences may be better understood in terms of rational statistical inference, based on their functional role in processes of causal discovery and theory revision. We present a formal definition of coincidences in the context of a Bayesian framework for causal induction: a coincidence is an event that provides support for an alternative to a currently favored causal theory, but not necessarily enough support to accept that alternative in light of its low prior probability. We test the qualitative and quantitative predictions of this account through a series of experiments that examine the transition from coincidence to evidence, the correspondence between the strength of coincidences and the statistical support for causal structure, and the relationship between causes and coincidences. Our results indicate that people can accurately assess the strength of coincidences, suggesting that irrational conclusions drawn from coincidences are the consequence of overestimation of the plausibility of novel causal forces. We discuss the implications of our account for understanding the role of coincidences in theory change.     

Responses to Conflict and Cooperation in Adolescents with Anxiety and Mood Disorders

This study examined patterns of behavioral and emotional responses to conflict and cooperation in adolescents with anxiety/mood disorders and healthy peers. We compared performance on and emotional responses to the Prisoner’s Dilemma (PD) game, an economic exchange task involving conflict and cooperation, between adolescents with anxiety/depressive disorders (A/D) (N=21) and healthy comparisons (n = 29). Participants were deceived to believe their co-player (a pre-programmed computer algorithm) was another study participant. A/D adolescents differed significantly from comparisons in patterns of play and emotional response to the game. Specifically, A/D participants responded more cooperatively to cooperative overtures from their co-players; A/D girls also reported more anger toward co-players than did comparison girls. Our findings indicate that A/D adolescents, particularly females, respond distinctively to stressful social interchanges. These findings offer a first step toward elucidating the mechanisms underlying social impairment in youth with internalizing disorders. This research was supported by the Intramural Research Program of the NIH, NIMH.     

Decoupling Children’s Gender-based In-Group Positivity from Out-Group Negativity

In the current study we attempted to determine whether children’s gender-based intergroup biases reflect positive attitudes toward the in-group and/or negative attitudes toward the out-group. Third through fifth grade children were asked to determine whether positive and negative traits described boys, girls, both genders, or nobody. This methodology allowed for separate evaluation of in-group favoritism and out-group derogation. Girls and children who perceived their gender as important viewed their in-group as having more positive than negative attributes and more positive and less negative attributes than the out-group. Boys and children who viewed gender as less important viewed both genders as having more positive than negative attributes. These results support Brewer’s (Journal of Social Issues 55:429–444, 1999) claim that in-group love and out-group hate are not reciprocally related.     

Measuring and modeling facial affect

In recent years, researchers in computer science and human-computer interaction have become increasingly interested in characterizing perception of facial affect. Ironically, this applied interest comes at a time when the classic findings on perception of human facial affect are being challenged in the psychological research literature, largely on methodological grounds. This paper first describes two experiments that empirically address Russell’s methodological criticisms of the classic work on measuring “basic emotions,” as well as his alternative approach toward modeling “facial affect space.” Finally, a user study on affect in a prototype model of a robot face is reported; these results are compared with the human findings from Experiment 1. This work provides new data on measuring facial affect, while also demonstrating how basic and more applied research can mutually inform one another.     

The development of stimulus control over tics: A potential explanation for contextually-based variability in the symptoms of Tourette syndrome

Research has demonstrated that providing reinforcement for tic-free intervals can decrease tic frequency in controlled analogue settings. The aim of the current study was to determine whether reinforcement could be used to create stimulus control over tic expression. Ten children with chronic tic disorders (including Tourette syndrome) completed four discrimination training sessions. Each session consisted of three exposures to each of three, 5 min conditions presented in a random order. In one condition, participants were reinforced for tic absence on a 10-s fixed interval schedule in the presence of a purple light. In a second condition, participants were instructed to suppress their tics, but were not reinforced for doing so in the presence of an orange light. In a third condition, participants were instructed not to suppress their tics in the presence of two non-illuminated lights. Confirming findings from other studies, results showed that reinforcing tic suppression reduced tic frequency to a greater extent than only providing instructions to suppress. To test for stimulus control, a fifth session was conducted following the aforementioned discrimination training sessions. The fifth session consisted of three exposures to each of three 5 min conditions presented in a random order. In one condition, a purple light was illuminated. In a second condition, an orange light was illuminated. In a third condition, neither light was illuminated. Across all three conditions, instructions to suppress (or not suppress) tics were not provided, and reinforcers for successful suppression were not delivered. Results indicated that in the presence of the purple light, tics were significantly lower than when neither light was illuminated. These findings provide preliminary support for the idea that a history of differential reinforcement in various contexts may play a role explaining variability in tic symptom expression.