Neural Correlates of Reward Processing in Adolescents With a History of Inhibited Temperament

ABSTRACT— Functional imaging data were acquired during performance of a reward-contingency task in a unique cohort of adolescents (ages 14–18 years) who were characterized since infancy on measures of temperamental behavioral inhibition. Neural activation was examined in striatal structures (nucleus accumbens, putamen, caudate) with a known role in facilitating response to salient reward-related cues. Adolescents with a history of behavioral inhibition, relative to noninhibited adolescents, showed increased activation in the nucleus accumbens when they believed their selection of an action would affect reward outcome. Neural responses did not differ between the two groups when participants made a prespecified response that they knew would result in reward or when they produced random motor responses that they knew would not be rewarded. These results link inhibited temperament and perturbed neural responses to reward-contingency cues.     

Very brief exposure: The effects of unreportable stimuli on fearful behavior

A series of experiments tested the hypothesis that very brief exposure to feared stimuli can have positive effects on avoidance of the corresponding feared object. Participants identified themselves as fearful of spiders through a widely used questionnaire. A preliminary experiment showed that they were unable to identify the stimuli used in the main experiments. Experiment 2 (N = 65) compared the effects of exposure to masked feared stimuli at short and long stimulus onset asynchronies (SOA). Participants were individually administered one of three continuous series of backwards masked or non-masked stimuli: unreportable images of spiders (25-ms SOA), clearly visible images of spiders (500-ms SOA), or unreportable images of trees (25-ms SOA). Immediately thereafter, they engaged in a Behavioral Avoidance Test (BAT) with a live, caged tarantula. Exposure to unreportable images of spiders resulted in greater approach towards the tarantula than unreportable neutral images. A post-hoc comparison with clearly visible exposure to these same images approached significance. These effects were maintained at a 1-week follow-up (N = 57). In Experiment 3 (N = 26), participants engaged in the BAT 1 week prior to the exposure manipulation in order to provide a baseline measurement of their avoidant behavior, and again immediately after the exposure manipulation. Exposure to unreportable images of spiders reduced avoidance of the tarantula. Similar exposure to trees did not. Implications for the non-conscious basis of fear are discussed.     

Acetylcholine activity in selective striatal regions supports behavioral flexibility

Daily living often requires individuals to flexibly respond to new circumstances. There is considerable evidence that the striatum is part of a larger neural network that supports flexible adaptations. Cholinergic interneurons are situated to strongly influence striatal output patterns which may enable flexible adaptations. The present experiments investigated whether acetylcholine actions in different striatal regions support behavioral flexibility by measuring acetylcholine efflux during place reversal learning. Acetylcholine efflux selectively increased in the dorsomedial striatum, but not dorsolateral or ventromedial striatum during place reversal learning. In order to modulate the M2-class of autoreceptors, administration of oxotremorine sesquifumurate (100 nM) into the dorsomedial striatum, concomitantly impaired reversal learning and an increase in acetylcholine output. These effects were reversed by the m(2) muscarinic receptor antagonist, AF-DX-116 (20 nM). The effects of oxotremorine sesquifumurate and AF-DX-116 on acetylcholine efflux were selective to behaviorally-induced changes as neither treatment affected acetylcholine output in a resting condition. In contrast to reversal learning, acetylcholine efflux in the dorsomedial striatum did not change during place acquisition. The results reveal an essential role for cholinergic activity and define its locus of control to the dorsomedial striatum in cognitive flexibility.     

A Social-Cognitive-Ecological Framework for Understanding the Impact of Exposure to Persistent Ethnic–Political Violence on Children’s Psychosocial Adjustment

In this article, we describe a theoretical framework for understanding how persistent and extreme exposure to ethnic–political conflict and violence interacts with cognitive, emotional, and self processes to influence children’s psychosocial adjustment. Three recent strands of theorizing guide our approach. First, we focus on how observational and social learning processes combine to influence the development of social-cognitive structures and processes that affect behavior. Second, we focus on the role of developing self and identity processes in shaping the child’s interactions with the world and the consequences of those interactions. Third, we build on the complex systems perspective on development and assume that human development can only be understood accurately by examining how the multiple contexts affecting children and the adults in their lives interact to moderate biosocial factors which predispose individuals to develop in certain directions. We review the recent empirical literature on children’s exposure to ethnic–political violence and we apply the social-cognitive-ecological framework to the empirical findings in this literature. Finally, we propose future directions for research and clinical implications derived from this framework.     

Responsibility and the Brain Sciences

Some theorists think that the more we get to know about the neural underpinnings of our behaviors, the less likely we will be to hold people responsible for their actions. This intuition has driven some to suspect that as neuroscience gains insight into the neurological causes of our actions, people will cease to view others as morally responsible for their actions, thus creating a troubling quandary for our legal system. This paper provides empirical evidence against such intuitions. Particularly, our studies of folk intuitions suggest that (1) when the causes of an action are described in neurological terms, they are not found to be any more exculpatory than when described in psychological terms, and (2) agents are not held fully responsible even for actions that are fully neurologically caused.     

Effects of verbal information on fear-related reasoning biases in children

The present study made an attempt to induce fear-related reasoning biases by providing children with negative information about a novel stimulus. For this purpose, non-clinical children aged 9-12 years (N = 318) were shown a picture of an unknown animal for which they received either negative, ambiguous, positive, or no information. Then children completed a series of tests for measuring various types of reasoning biases (i.e., confirmation bias and covariation bias) in relation to this animal. Results indicated that children in the negative and, to a lesser extent, the ambiguous information groups displayed higher scores on tests of fear-related reasoning biases than children in the positive and no information groups. Altogether, these results support the idea that learning via negatively tinted information plays a role in the development of fear-related cognitive distortions in youths.     

AN EVALUATION OF THE INTERACTION BETWEEN QUALITY OF ATTENTION AND NEGATIVE REINFORCEMENT WITH CHILDREN WHO DISPLAY ESCAPE‐MAINTAINED PROBLEM BEHAVIOR

The choice‐making behavior of 2 typically developing children who engaged in problem behavior maintained by negative reinforcement was evaluated within a concurrent‐operants assessment that varied the quality of attention across free‐play and demand conditions. The results demonstrated that it was possible to bias responding towards academic demands for both participants by providing high‐quality attention, despite the continuous availability of negative reinforcement. The current study extended brief clinical methods with typically developing children and demonstrated how different qualities of attention provided across concurrent schedules could bias responding.     

a test of holland's theory of vocational personalities and work environments

This study investigated the validity of J. L. Holland's (1997) theory of vocational personalities and work environments. The sample consisted of 241 randomly selected members of the National Association of School Psychologists, each of whom completed a demographic data form, the Self‐Directed Search‐Revised (SDS‐R; J. L. Holland, 1994) and a modified short form of the Minnesota Satisfaction Questionnaire (D. J. Weiss, R. V. Dawis, G. W. England, & L. H. Lofquist, 1967). Only limited support was found for major constructs associated with Holland's theory, although the study found several significant relationships between 3‐letter SDS‐R codes and desired role function as would be predicted by Holland's theory.     

“I Feel Your Pain”: The effects of observing ostracism on the ostracism detection system

Ostracism—being ignored and excluded—is a painful experience with negative psychological consequences. Social psychologists ( [Kerr and Levine, 2008] and [Spoor and Williams, 2007] ) argue humans have an evolved system for automatically detecting cues of ostracism and exclusion. Detection elicits pain and threats to fundamental needs. We hypothesize simply observing ostracism will cause negative affect and need threat in the observer. Participants observed a three-player Cyberball game; a target player was included or ostracized, and participants were either instructed to take the perspective of this player or given no such instructions. Participants observing ostracism reported negative affect and need threat. Our results indicate that ostracism detection is even more powerful than previously suggested, because vicariously, we feel the pain of others’ ostracism as our own.     

Orthographic vs. phonologic syllables in handwriting production

French children program the words they write syllable by syllable. We examined whether the syllable the children use to segment words is determined phonologically (i.e., is derived from speech production processes) or orthographically. Third, 4th and 5th graders wrote on a digitiser words that were mono-syllables phonologically (e.g. barque = [baRk]) but bi-syllables orthographically (e.g. barque = bar.que). These words were matched to words that were bi-syllables both phonologically and orthographically (e.g. balcon = [bal.kõ] and bal.con). The results on letter stroke duration and fluency yielded significant peaks at the syllable boundary for both types of words, indicating that the children use orthographic rather than phonological syllables as processing units to program the words they write.