Dissociable effects of basolateral amygdala lesions on decision making biases in rats when loss or gain is emphasized

Individuals switch from risk seeking to risk aversion when mathematically identical options are described in terms of loss versus gains, as exemplified in the reflection and framing effects. Determining the neurobiology underlying such cognitive biases could inform our understanding of decision making in health and disease. Although reports vary, data using human subjects have implicated the amygdala in such biases. Animal models enable more detailed investigation of neurobiological mechanisms. We therefore tested whether basolateral amygdala (BLA) lesions would affect risk preference for gains or losses in rats. Choices in both paradigms were always between options of equal expected value—a guaranteed outcome, or the 50:50 chance of double or nothing. In the loss-chasing task, most rats exhibited strong risk seeking preferences, gambling at the risk of incurring double the penalty, regardless of the size of the guaranteed loss. In the betting task, the majority of animals were equivocal in their choice, irrespective of bet size; however, a wager-sensitive subgroup progressively shifted away from the uncertain option as the bet size increased, which is reminiscent of risk aversion. BLA lesions increased preference for the smaller guaranteed loss in the loss-chasing task, without affecting choice on the betting task, which is indicative of reduced risk seeking for losses, but intact risk aversion for gains. These data support the hypothesis that the amygdala plays a more prominent role in choice biases related to losses. Given the importance of the amygdala in representing negative affect, the aversive emotional reaction to loss, rather than aberrant estimations of probability or loss magnitude, may underlie risk seeking for losses.     

Coping Strategies and Psychological Outcomes: The Moderating Effects of Personal Resiliency

Certain coping strategies alleviate stress and promote positive psychological outcomes, whereas others exacerbate stress and promote negative psychological outcomes. However, the efficacy of any given coping strategy may also depend on personal resiliency. This study examined whether personal resiliency moderated the effects of task-oriented, avoidance-oriented, and emotion-oriented coping strategies on measures of depression, anxiety, stress, positive affect, negative affect, and satisfaction with life. Results (N = 424 undergraduates) showed higher personal resiliency was associated with greater use of task-oriented coping strategies, which were in turn associated with more adaptive outcomes, and less reliance on nonconstructive emotion-oriented strategies, which in turn were associated with poorer psychological outcomes. In addition, individual differences in personal resiliency moderated the effects of task-oriented coping on negative affect and of emotion-oriented coping on negative affect and depression. Specifically, proactive task-oriented coping was associated with greater negative affect for people lower in personal resiliency. Moreover, high personal resiliency attenuated the negative effects of emotion-oriented coping on depression and negative affect. The effects of avoidance-oriented coping were mixed and were not associated with or dependent on levels of personal resiliency.     

Associations of Mother’s and Father’s Parenting Practices with Children’s Observed Social Reticence in a Competitive Situation: A Monozygotic Twin Difference Study

This study used the monozygotic (MZ) twin difference method to examine whether the unique environmental effects of maternal and paternal overprotection and hostility at the age of 30 months predict twins’ observed social reticence in a competitive situation in kindergarten, while controlling for the effect of family-wide influences, including genetic and shared environmental factors, family socio-economical status and twin’s birth weight. It was also examined whether these associations are moderated by parental depressive symptoms. Participants were 137 MZ twin pairs who were part of an ongoing longitudinal study. Hierarchical linear regressions revealed that differences in maternal and paternal overprotection predicted differences in twins’ social reticence, albeit only in boys. Differences in paternal hostile parenting predicted differences in girls’ reticent behavior, but only when fathers showed high levels of depressive symptoms. Hence, overprotected boys, as well as girls confronted with father’s hostility and depressive symptoms, may tend to withdraw rather than face the challenge when experiencing difficult social situations such as competition. The results from the present study suggest that targeting maladaptive maternal as well as paternal child-rearing practices and psychopathology early on may be useful for reducing later internalizing behavior in the offspring.     

The effect of path length and display size on memory for spatial information

In serial memory for spatial information, some studies showed that recall performance suffers when the distance between successive locations increases relatively to the size of the display in which they are presented (the path length effect; e.g., Parmentier et al., 2005) but not when distance is increased by enlarging the size of the display (e.g., Smyth & Scholey, 1994). In the present study, we examined the effect of varying the absolute and relative distance between to-be-remembered items on memory for spatial information. We manipulated path length using small (15″) and large (64″) screens within the same design. In two experiments, we showed that distance was disruptive mainly when it is varied relatively to a fixed reference frame, though increasing the size of the display also had a small deleterious effect on recall. The insertion of a retention interval did not influence these effects, suggesting that rehearsal plays a minor role in mediating the effects of distance on serial spatial memory. We discuss the potential role of perceptual organization in light of the pattern of results.     

Disruption of verbal-spatial serial memory by extraneous air-traffic speech

The disruptive impact of task-extraneous air-traffic radio speech on a task involving the serial-recall of combined verbal and spatial stimuli (7 letters and their locations) that were broadly analogous to information about aircraft callsigns and movements was examined. Regardless of the dimension to be recalled (identity or spatial location), accuracy was significantly disrupted by the air-traffic speech. Prior knowledge as to which dimension to recall did not affect accuracy and did not interact with the disruptive effect of air-traffic speech, but did extend the time to initiate a response to the first item. The results are discussed with reference to theories of the irrelevant sound effect and stimulus-dimension binding in short-term memory. The vulnerability of cognitive processing related to air-traffic management and similar work environments is also discussed.