The effect of high ambient temperature on timing behavior in rats

The present experiments demonstrated a reliable within-session increase in rectal temperature (T(re)) at 25 degrees C during stable differential-reinforcement-of-low-rate (DRL) performance. The thermal response was found to be independent of the DRL value and reinforced DRL performance, but dependent on the state of the animal's deprivation. Exposure to a 35 degrees -C environment increased the post-session T(re) significantly above the 25 degrees -C post-session T(re) for seven of eight subjects. Response and reinforcement rate at 35 degrees C was found to be independent of DRL value, although it decreased as DRL value increased at 25 degrees C. A discriminative stimulus used to mark the end of the interval increased the reinforcement rate at 25 degrees C but provided no advantage at 35 degrees C. Measurement of the pattern of responding during DRL performance revealed increases in the proportion of long interresponse times at 35 degrees C. Reinforcement rate was found to decrease progressively at 35 degrees C, reaching a minimum within 40 to 50 min of the 90-min session. Visual observation of overt behaviors during DRL performance at 35 degrees C revealed a reduction in the frequency of overt behavior, characteristic of 25 degrees -C performance, and a time-dependent increase in the probability of an alternative set of behaviors.     

Patient Personality and Relational Patterns in Psychotherapy: Factor Structure,Reliability, and Validity of the Psychotherapy Relationship Questionnaire

The aim of this study was to examine the factor structure and the psychometric properties of the Psychotherapy Relationship Questionnaire (PRQ; Bradley, Heim, &; Westen, 2005 Bradley, R., Heim, A. K., &; Westen, D. (2005). Transference patterns in the psychotherapy of personality disorders: Empirical investigation. The British Journal of Psychiatry, 186, 342–349. doi:10.1192/bjp.186.4.342[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]), a clinician report instrument that measures a wide spectrum of thoughts, feelings, motives, conflicts, and behaviors expressed by patients toward their therapists in psychotherapy. A national sample of psychiatrists and clinical psychologists (N = 314) of different theoretical orientations completed the PRQ, as well as the Shedler–Westen Assessment Procedure–200 (SWAP–200; Westen &; Shedler, 1999a Westen, D., &; Shedler, J. (1999a). Revising and assessing Axis II, Part I: Developing a clinically and empirically valid assessment method. The American Journal of Psychiatry, 156, 258–272.[PubMed], [Web of Science ®] , [Google Scholar], 1999b Westen, D., &; Shedler, J. (1999a). Revising and assessing Axis II, Part I: Developing a clinically and empirically valid assessment method. The American Journal of Psychiatry, 156, 258–272.[PubMed], [Web of Science ®] , [Google Scholar]) to assess the personality of a patient in their care. Factor-analytic procedures identified 6 transference dimensions that showed excellent internal consistencies: (a) hostile, (b) positive/working alliance, (c) special/entitled, (d) anxious/preoccupied, (e) avoidant/dismissing attachment, and (f) sexualized. Factor scores were significantly related to patients’ personality characteristics and psychological functioning, regardless of the clinicians’ orientations. The findings support that the PRQ is a valid and reliable tool for evaluating the patients’ relational patterns emerging in clinical practice in a clinically coherent and psychometrically robust way. Clinicians’ careful understanding of these patterns can be very useful for making accurate diagnostic formulations, as well as for providing a roadmap for effective therapeutic intervention.     

HPA-Axis Activation as a Key Moderator of Childhood Trauma Exposure and Adolescent Mental Health

Individual differences in a child’s sensitivity to stress may influence whether youth exposed to trauma develop symptoms of psychopathology. We examined the interaction between HPA-axis reactivity to an acute stressor and exposure to different types of childhood trauma as predictors of mental health symptoms in a sample of youth. Youth (n?=?121, ages 9–16; 47% female) completed a standardized stress task, including 5 post-stress salivary cortisol samples. Parents also completed the Child Behavior Checklist as a measure of child internalizing and externalizing symptoms in the past month, and completed the Early Trauma Inventory (ETI) as a measure of their child’s trauma exposure. More emotional abuse and non-intentional trauma were associated with greater internalizing symptoms. Youth exposed to physical abuse who demonstrated slower HPA-axis reactivity had elevated internalizing and externalizing symptoms. Youth exposed to emotional abuse or non-intentional traumatic events who demonstrated faster HPA-axis reactivity had elevated internalizing and externalizing symptoms. Profiles of exaggerated or attenuated HPA-axis reactivity to acute stress may be risk factors for psychopathology in children facing different stressful social environments.     

Evaluating risk propensity using an objective instrument

Risk propensity is the stable tendency to choose options with a lower probability of success, but greater rewards. Its evaluation has been approached from various perspectives: from self-report questionnaires to objective tests. Self-report questionnaires have often been criticized due to interference from voluntary and involuntary biases, in addition to their lack of predictive value. Objective tests, on the other hand, require resources that make them difficult to administer to large samples. This paper presents an easy-to-administer, 30-item risk propensity test. Each item is itself an objective test describing a hypothetical situation in which the subject must choose between three options, each with a different gain function but equivalent in expected value. To assess its psychometric fit, the questionnaire was administered to 222 subjects, and we performed a test of its reliability as well as exploratory factor analysis. The results supported a three-factor model of risk (Sports and Gambling, Long-term Plans, and Loss Management). After making the necessary adjustments and incorporating a global factor of risk propensity, confirmatory factor analysis was done, revealing that the data exhibited adequate goodness of fit.     

The interplay of spatial attention and memory: evidence for memory-driven spatial compatibility effects, but not for a facilitating role of attention in memory retrieval

The visual indexing theory proposed by Zenon Pylyshyn (Cognition, 32, 65-97, 1989) predicts that visual attention mechanisms are employed when mental images are projected onto a visual scene. Recent eye-tracking studies have supported this hypothesis by showing that people tend to look at empty places where requested information has been previously presented. However, it has remained unclear to what extent this behavior is related to memory performance. The aim of the present study was to explore whether the manipulation of spatial attention can facilitate memory retrieval. In two experiments, participants were asked first to memorize a set of four objects and then to determine whether a probe word referred to any of the objects. The results of both experiments indicate that memory accuracy is not affected by the current focus of attention and that all the effects of directing attention to specific locations on response times can be explained in terms of stimulus-stimulus and stimulus-response spatial compatibility.     

Serotonin transporter (5-HTTLPR) genotype, childhood abuse, and suicide attempts in adult psychiatric inpatients

There is growing evidence that a functional polymorphism in the serotonin transporter gene (5-HTTLPR) moderates the impact of negative life events (e.g., childhood abuse) on the development of depression. However, it is unclear whether the gene x environment interaction predicts suicide attempts specifically. In addition, previous studies have not examined different forms of childhood abuse separately. In the current study, we found that 5-HTTLPR genotype moderated the link between childhood physical and sexual, but not emotional, abuse and adult psychiatric inpatients' histories of suicide attempts.     

Openness to experience and boundaries in the mind: relationships with cultural and economic conservative beliefs

The present research investigates whether Openness to Experience and Boundaries in the mind are related to conservatism. In the first study, significant relationships between several scales of the Boundaries in the mind questionnaire and indicators of conservative beliefs were obtained in an adult sample (N=78) as well as in a sample of political party activists (N=44). In the second study, these negative relationships between conservatism and thin boundaries were replicated in an adult sample (N=225). Moreover, two dimensions representing Boundaries in the mind were identified, one positively related to Openness to Experience and negatively to conservatism and the second showing high positive correlations with Neuroticism. The exceptionally strong correlations between conservatism and the Boundaries in the mind facet scales Opinions about organizations, Opinions about beauty, truth, Edges, lines, clothing and Opinions about peoples, nations, groups are discussed, as well as the weak relationships between economic conservatism and Openness to Experience.     

Application of Sequential Interval Estimation to Adaptive Mastery Testing

In this paper, we apply sequential one-sided confidence interval estimation procedures with β-protection to adaptive mastery testing. The procedures of fixed-width and fixed proportional accuracy confidence interval estimation can be viewed as extensions of one-sided confidence interval procedures. It can be shown that the adaptive mastery testing procedure based on a one-sided confidence interval with β-protection is more efficient in terms of test length than a testing procedure based on a two-sided/fixed-width confidence interval. Some simulation studies applying the one-sided confidence interval procedure and its extensions mentioned above to adaptive mastery testing are conducted. For the purpose of comparison, we also have a numerical study of adaptive mastery testing based on Wald's sequential probability ratio test. The comparison of their performances is based on the correct classification probability, averages of test length, as well as the width of the “indifference regions.” From these empirical results, we found that applying the one-sided confidence interval procedure to adaptive mastery testing is very promising.     

Fragile X mental retardation protein levels increase following complex environment exposure in rat brain regions undergoing active synaptogenesis

Fragile X mental retardation protein (FMRP), which is absent in fragile X syndrome, is synthesized in vitro in response to neurotransmitter activation. Humans and mice lacking FMRP exhibit abnormal dendritic spine development, suggesting that this protein plays an important role in synaptic plasticity. Previously, our laboratory demonstrated increased FMRP immunoreactivity in visual cortex of rats exposed to complex environments (EC) and in motor cortex of rats trained on motor-skill tasks compared with animals reared individually in standard laboratory housing (IC). Here, we use immunohistochemistry to extend those findings by investigating FMRP levels in visual cortex and hippocampal dentate gyrus of animals exposed to EC or IC. Rats exposed to EC for 20 days exhibited increased FMRP immunoreactivity in visual cortex compared with animals housed in standard laboratory caging. In the dentate gyrus, animals exposed to EC for 20 days had higher FMRP levels than animals exposed to EC for 5 or 10 days. In light of possible antibody crossreactivity with closely related proteins FXR1P and FXR2P, FMRP immunoreactivity in the posterior-dorsal one-third of cerebral cortex was also examined by Western blotting following 20 days of EC exposure. FMRP levels were greater in EC animals, whereas levels of FXR1P and FXR2P were unaffected by experience. These results provide further evidence for behaviorally induced alteration of FMRP expression in contrast to its homologues, extend previous findings suggesting regulation of its expression by synaptic activity, and support the theories associating FMRP expression with alteration of synaptic structure both in development and later in the life-cycle.