Hope and dysphoria: the moderating role of defense mechanisms

It was hypothesized that the adaptive value of hope cognitions would be dependent upon the quality of an individual's defense style. Undergraduate students completed measures of hope, defense mechanisms, and dysphoria in two studies. As predicted, defense mechanisms significantly moderated the relation between hope and dysphoria. In addition, both hope and defense mechanisms predicted dysphoria as main effects. Individuals who had low hope and an immature defense style had particularly high levels of dysphoria. Low hope was not maladaptive for individuals with a mature defense style, suggesting that a subtype of low hope ("defensive hopelessness") may exist that is analogous to defensive pessimism. Individuals with high hope had low levels of dysphoria regardless of defense style. Overall, the present study suggests that an integration of psychodynamic and cognitive perspectives on hope may be productive.     

Glutamate-mediated neuroplasticity in a limbic input to the hypothalamus

Emotionally-salient stressors are processed by cortical and limbic circuits that provide important regulatory input to the hypothalamic-pituitary-adrenal (HPA) axis. However, exposure to chronic or severe stress may cause disregulation of the axis and a variety of physiological and psychological symptoms. The mechanisms that underlie stress-induced alterations in HPA axis function are not well characterized, but one possibility is that severe stress causes plastic changes in limbic inputs to the hypothalamus. We examined plasticity within the bed nucleus of stria terminalis (BNST) and the hypothalamic paraventricular nucleus (PVN) with a stimulating electrode in the BNST and a recording electrode in the PVN. High-frequency BNST stimulation produced long-lasting suppression of evoked field potentials recorded from the PVN, and this effect was blocked by administration of MK-801. Accordingly, rapid glutamate-mediated neuroplasticity in the BNST to PVN neurocircuitry may contribute to plasticity in limbic regulation of the HPA axis.     

Detecting structural and functional neuroplasticity in elite ice-skating athletes

Using resting-state fMRI, this study investigated long-term ice-skating training related changes in elite ice-skating athletes and compared them to healthy age-matched non-athletes under resting-state conditions. Significant differences were found in both structural and functional plasticity. Specifically, elite ice-skating athletes showed higher gray matter volume in the posterior cerebellum, frontal lobe, temporal lobe, posterior cingulate, caudate, and thalamus. The functional plasticity changes were primarily concentrated in the posterior cerebellar lobe. Additionally, stronger connectivity between the posterior cerebellar lobe and fusiform gyrus was also found in elite ice-skating athletes. Overall, the results are consistent with other studies that concluded long-term professional motor skill training can cause structural and functional plasticity in the regions of the brain related to motor planning, execution, and supervision. Both structural plasticity and functional plasticity are primarily enhanced in the posterior cerebellum. These changes may be related to the outstanding capability of speed and coordination caused by long-term ice-skating training. Present results add new evidence and may help us to understand the neural mechanisms of long-term motor skill training.     

Neural predictive mechanisms and their role in cognitive incrementalism

Many neuroscientists view prediction as one of the core brain functions, especially on account of its support of fast movements in complex environments. This leads to the natural question whether predictive knowledge forms the cornerstone of our common-sense understanding of the world. However, there is little consensus as to the exact nature of predictive information and processes, or of the neural mechanisms that realize them. This paper compares procedural versus declarative notions of prediction, examines how the brain appears to carry out predictive functions, and discusses to what degree, and at what level, these neural mechanisms support cognitive incrementalism: the notion that high-level cognition stems from sensorimotor behavior.     

Differential role of the hippocampal endocannabinoid system in the memory consolidation and retrieval mechanisms

CB1 cannabinoid receptors are abundantly expressed in the brain, with large concentrations present in the hippocampus, a brain structure essential for memory processing. In the present study, we have investigated the possible modulatory role of the endocannabinoid system in the dorsal hippocampus upon the different phases of memory processing of an aversive task. AM251, a selective antagonist of CB1 receptors, and anandamide, an endogenous agonist of cannabinoid receptors, were bilaterally infused into the dorsal hippocampus of male Wistar rats either before training, immediately after training, or before test in the step-down inhibitory avoidance (IA) task. Results showed that pre-training infusion of CB1 drugs did not influence the acquisition of the task. In contrast, post-training infusion of the CB1 antagonist disrupted while the antagonist facilitated memory consolidation of IA. The post-training results demonstrate that memory consolidation depends on the integrity of the endocannabinoid system in the CA1 region of the dorsal hippocampus. While we still have no direct proof of endocannabinoids released there after an aversive task such as IA, these results suggests that (a) AM251 acts blocking the binding of endogenously released cannabinoids and (b) exogenously supplemented anandamide may be adding its contribution to the action of the endogenously released pool. Considering our data and the higher density of CB1 receptors present in the GABAergic interneurons, we propose them as the putative target of the endocannabinoid modulation of memory, a hypothesis that needs to be proven. In addition, pre-test infusion of the CB1 receptor antagonist facilitated while infusion of the agonist did not affect memory retrieval of IA. The completely opposite action of the same drug upon memory at the post-training (consolidation) and pre-test (recall) contexts suggests that some durable change took place in the CA1 region during the consolidation process that modified the logical attributes of the pharmacological response, i.e., the drug response changed from memory disruption to memory facilitation. A similar phenomenon was previously described by us in the M4 cholinergic muscarinic subsystem in the hippocampus for the same task (Diehl, F., Fürstenau, L. O., Sanchez, G., Camboim, C., de Oliveira Alvares, L., Lanziotti, V. B., et al. (2007). Facilitatory effect of the intra-hippocampal pretest administration of MT3 in the inhibitory avoidance task. Behavioral Brain Research, 177(2), 227-231), but the biological nature of such change in the local neural circuitry remains to be investigated.     

Probing the link between narcissism and gambling: the mediating role of judgment and decision‐making biases

In this paper, three studies link narcissism to gambling in general, and gambling‐related problems in particular, and the predictive link is shown to be mediated by judgment and decision processes. In Study 1, we demonstrate that narcissism relates to greater self‐reported gambling frequency and gambling‐related monetary expenditures in two samples. We extend these initial findings in Study 2 by showing that narcissism predicts higher reports of gambling‐related pathology, as measured with a DSM‐IV‐based pathological gambling (PG) screen. Finally, we demonstrate in Study 3 that the link between gambling pathology and narcissism is partially mediated by narcissists' overconfidence, heightened risk acceptance, and myopic focus on reward, as measured by participants' behavioral performance on the Georgia Gambling Task (GGT) and Iowa Gambling Task (IGT). Discussion focuses on the empirical validation of the long‐assumed narcissism–gambling link, the decision processes that underlie this link, and relations between narcissists' self‐perceptions and their self‐defeating behavior, especially in risk‐relevant contexts. Copyright © 2007 John Wiley & Sons, Ltd.     

Adult attachment style and the perception of others: the role of projective mechanisms.

In 3 reported studies the authors examined attachment-style differences in the perception of others and the hypothesis that projective mechanisms underlie these differences. In these studies, participants reported on their attachment style and generated actual-self-traits and unwanted-self-traits. Then, a 2nd session was conducted, in which impression formation about new persons (Study 1), the ease of retrieval of memories about known persons (Study 2), or memory inferences about learned features of fictional persons (Study 3) were assessed. Findings indicate that whereas anxious-ambivalent persons' impression formation, memory retrieval, and inferences about others reflected the projection of their actual-self-traits, avoidant persons' responses reflected the projection of their unwanted-self-traits. Findings are discussed in terms of the regulatory goals and strategies that characterize the mental representations of each attachment style.     

Understanding the relationship between obesity and positive and negative affect: the role of psychosocial mechanisms

We examined the relationship between body mass index (BMI) and positive and negative affect, and evaluated whether this relationship is mediated (or suppressed) by physical health, intrusiveness of weight on physical functioning, and distressing interpersonal interactions. Analyses were based on a national sample of more than 3,000 adults ages 25 to 74. Class II (BMI 35–39.9) and Class III (BMI ≥ 40) obesity were associated with more frequent negative affect and less frequent positive affect, even after demographic and socioeconomic status characteristics were controlled. After the purported pathway variables were controlled, however, obese I persons reported significantly more frequent positive affect, while overweight, obese I, and obese II persons reported significantly less frequent negative affect, compared to normal weight persons. These patterns did not differ significantly by race or gender. Our findings suggest that excessive body weight is not necessarily distressing, yet the physical and interpersonal strains associated with obesity may impair one's mood. We discuss the implications for policy and practice.     

Stress risk factors and stress-related pathology: neuroplasticity, epigenetics and endophenotypes

This paper highlights a symposium on stress risk factors and stress susceptibility, presented at the Neurobiology of Stress workshop in Boulder, CO, in June 2010. This symposium addressed factors linking stress plasticity and reactivity to stress pathology in animal models and in humans. Dr. J. Radley discussed studies demonstrating prefrontal cortical neuroplasticity and prefrontal control of hypothalamo-pituitary-adrenocortical axis function in rats, highlighting the emerging evidence of the critical role that this region plays in normal and pathological stress integration. Dr. M. Kabbaj summarized his studies of possible epigenetic mechanisms underlying behavioral differences in rat populations bred for differential stress reactivity. Dr. L. Jacobson described studies using a mouse model to explore the diverse actions of antidepressants in brain, suggesting mechanisms whereby antidepressants may be differentially effective in treating specific depression endophenotypes. Dr. R. Yehuda discussed the role of glucocorticoids in post-traumatic stress disorder (PTSD), indicating that low cortisol level may be a trait that predisposes the individual to development of the disorder. Furthermore, she presented evidence indicating that traumatic events can have transgenerational impact on cortisol reactivity and development of PTSD symptoms. Together, the symposium highlighted emerging themes regarding the role of brain reorganization, individual differences, and epigenetics in determining stress plasticity and pathology.     

The role of urgency and its underlying psychological mechanisms in problematic behaviours

The urgency facet of impulsivity, that is, the tendency to act rashly in response to intense emotional contexts [Cyders, M. A., & Smith, G. T. (2008). Emotion-based dispositions to rash action: positive and negative urgency. Psychological Bulletin, 134, 807-828], has been related to a wide range of maladaptive behaviours. The present study further investigates the role of urgency in problematic behaviours by considering distinct psychological mechanisms that may underlie this component of impulsivity. With this aim, 95 volunteer participants were screened with self-reported questionnaires assessing urgency and three problematic behaviours (compulsive buying, excessive mobile phone use, excessive Internet use). They performed two laboratory tasks: a stop-signal task designed to assess the capacity to inhibit prepotent responses in response to both neutral and emotional stimuli; and the Iowa Gambling Task (IGT) measuring the ability to take into account the future consequences of an action. A poor ability to inhibit prepotent responses in the emotional condition of the stop-signal task was found to predict more disadvantageous choices in the IGT, which ultimately results in higher urgency and more problematic behaviours. These findings shed new light on the construct of urgency, its related psychological mechanisms, and its role in problematic behaviours.     

Lay understandings of defence mechanisms: The role of personality traits and gender

This study looks at lay people's knowledge and use of the defence mechanisms. It focused on 21 of the better known "Freudian" defence mechanisms. A total of 208 participants (73 males and 135 females) completed a questionnaire regarding their knowledge and reported personal use of 21 defence mechanisms and a short personality test. Participants were required to state (1) whether they had heard of each mechanism, (2) how common they believed it to be and (3) whether they themselves used each of them. The defences were categorised into four levels: Pathological, immature, neurotic and mature. Two personality traits (Openness and Neuroticism) positively correlated with two of the levels but few gender or age correlations were identified. Regression analysis showed that Neuroticism predicted the three less mature defence levels; Gender was a contributing predictor of a pathological defence style and Openness and religiosity combined with Neuroticism predicted an immature defence style. Participants admitted using the more socially acceptable (mature) defences (i.e. humour, intellectualisation) than the less acceptable (pathological) defences (i.e. distortion, hypochondriasis). Implications for psychotherapy are discussed and the limitations of the study considered.     

The role of higher level adaptive coding mechanisms in the development of face recognition

Developmental improvements in face identity recognition ability are widely documented, but the source of children’s immaturity in face recognition remains unclear. Differences in the way in which children and adults visually represent faces might underlie immaturities in face recognition. Recent evidence of a face identity aftereffect (FIAE), in which adaptation (exposure) to a particular identity causes a previously neutral face to take on the computationally opposite identity, suggests that adults code faces in an opponent fashion relative to an average face. One previous study showed comparable FIAEs in 8-year-olds and adults but did not demonstrate that adaptation was selective for high-level representations in both groups. Using a developmentally appropriate FIAE task, we investigated whether children show adult-like adaptation for facial identity when adapting and test images differ in size. Both age groups showed an equivalent FIAE, suggesting that qualitative changes in the use of higher level adaptive coding mechanisms do not drive the developmental improvements in face recognition ability, at least from 8 years of age.     

Probing the Fundamentalist Worldview

The following is a response to Calvin Mercer’s (2009) Slaves to Faith, A Therapist Looks Inside the Fundamentalist Mind from a multicultural pastoral perspective.     

Posttraumatic stress and physical health among adults: The role of coping mechanisms

The purpose of the present study was to examine whether coping mechanisms predict physical health, after controlling for posttraumatic stress disorder (PTSD) symptom clusters in a non-clinical sample of adults. Data were collected from 483 adults through an online survey. Most of the participants (66.7%) reported lifetime exposure to at least one traumatic event. The final sample of this study included 319 trauma-exposed individuals. Results indicated that PTSD symptoms on the avoidance and hyperarousal clusters had significant positive relationships with self-reported physical health symptoms. After controlling for gender and PTSD, denial, behavioral disengagement, and self-blame significantly and positively predicted physical health symptoms.     

The role of working memory capacity and interference resolution mechanisms in task switching

Theories of task switching have emphasized a number of control mechanisms that may support the ability to flexibly switch between tasks. The present study examined the extent to which individual differences in working memory (WM) capacity and two measures of interference resolution, response–distractor inhibition and resistance to proactive interference (PI), account for variability in task switching, including global costs, local costs, and N-2 repetition costs. A total of 102 young and 60 older adults were tested on a battery of tasks. Composite scores were created for WM capacity, response–distractor inhibition, and resistance to PI; shifting was indexed by rate residual scores, which combine response time and accuracy and account for individual differences in processing speed. Composite scores served as predictors of task switching. WM was significantly related to global switch costs. While resistance to PI and WM explained some variance in local costs, these effects did not reach significance. In contrast, none of the control measures explained variance in N-2 repetition costs. Furthermore, age effects were only evident for N-2 repetition costs, with older adults demonstrating larger costs than young adults. Results are discussed within the context of theoretical models of task switching.