Aggravation of DSS-induced colitis after chronic subordinate colony (CSC) housing is partially mediated by adrenal mechanisms

Chronic subordinate colony housing (CSC) is a relevant chronic psycho-social stressor for male mice. Here, we investigated effects of CSC on the severity of dextran sulphate sodium (DSS)-induced colitis and the involvement of adrenal mechanisms. After 19 days of CSC, male C57BL/6 mice were treated with 1% DSS (8 days). After 8 days, inflammatory shortening of the colon and the histological inflammation score were increased in CSC mice. Additionally, the increased secretion of pro-inflammatory cytokines by mesenteric lymph node cells found on day 2 and 4 of DSS treatment was down-regulated in CSC mice on day 8 of DSS treatment, paralleled by an increase in plasma corticosterone. In contrast, in unstressed controls, elevation of cytokine secretion was delayed and only found on day 8 of DSS treatment, associated with a prompt rise in plasma corticosterone. To reveal adrenal mechanisms in CSC-induced effects on colitis, mice were adrenalectomized, exposed to CSC and treated with DSS (8 days). In adrenalectomized CSC mice, the severity of DSS-induced colitis was reduced, as body weight loss, shortening of colon, histological damage score, and cytokine secretion from mesenteric lymph node cells were diminished compared with sham-operated CSC mice. In conclusion, exposure to chronic psycho-social stress increases the severity of acute DSS colitis, an effect which is, at least partly, mediated by adrenal mechanisms.     

Up-regulation of exploratory tendencies does not enhance general learning abilities in juvenile or young-adult outbred mice

"General cognitive ability" describes a trait that transcends specific learning domains and impacts a wide range of cognitive skills. Individual animals (including humans) exhibit wide variations in their expression of this trait. We have previously determined that the propensity for exploration is highly correlated with the general cognitive abilities of individual outbred mice. Here, we asked if inducing an increase in exploratory behaviors would causally promote an increase in animals' general learning abilities. In three experiments, juvenile and young-adult male CD-1 outbred mice were exposed to 12 novel environments starting at post-natal days 39 (juvenile) and 61 (young adult), after which they underwent a series of cognitive and exploratory tests as adults (beginning at post-natal day 79). Exposure to novel environments promoted increases in exploration (across multiple measures) on two different tasks, including an elevated plus maze. However, a subsequent test of general learning abilities (aggregate performance across five distinct learning tasks) determined that exposure to novel environments as juveniles or young-adults had no effect on general learning abilities in adulthood. Therefore, while exposure to novel environments promotes long-lasting increases in mice's exploratory tendencies, these increases in exploration do not appear to causally impact general learning abilities.     

When social anxiety disorder co-exists with risk-prone, approach behavior: Investigating a neglected, meaningful subset of people in the National Comorbidity Survey-Replication

Little is known about people with social anxiety disorder (SAD) who are not behaviorally inhibited. To advance knowledge on phenomenology, functional impairment, and treatment seeking, we investigated whether engaging in risk-prone behaviors accounts for heterogeneous outcomes in people with SAD. Using the National Comorbidity Survey-Replication (NCS-R) dataset, our analyses focused on people with current (N = 679) or lifetime (N = 1143) SAD diagnoses. Using latent class analysis on NCS-R risk-prone behavior items, results supported two SAD classes: (1) a pattern of behavioral inhibition and risk aversion and (2) an atypical pattern of high anger and aggression, and moderate/high sexual impulsivity and substance use problems. An atypical pattern of risk-prone behaviors was associated with greater functional impairment, less education and income, younger age, and particular psychiatric comorbidities. Results could not be subsumed by the severity, type, or number of social fears, or comorbid anxiety or mood disorders. Conclusions about the nature, course, and treatment of SAD may be compromised by not attending to heterogeneity in behavior patterns.     

Temporal distance and ease of retrieval

Construal Level Theory (CLT; Trope & Liberman, 2003) proposes that pro-arguments (pros) constitute high-level construals and counter-arguments (cons) low-level construals. Therefore, pros are more salient for distant-future actions than are cons and the reverse holds for near-future actions (Eyal, Liberman, Trope, & Walther, 2004). We further predicted and results from one experiment show that participants found it easier to generate pros if an action pertained to the distant rather than the near future. For cons the effect was reversed: participants found it more difficult to generate cons if the action pertained to the distant rather than the near future. Consequently, people were more in favor of the action if it pertained to the distant rather than the near future. Ease of retrieval mediated the effect of temporal distance on attitudes. The mutual relevance of the CLT framework and research on ease of retrieval is discussed.     

Assessing Children's Homework Performance: Development of Multi-Dimensional, Multi-Informant Rating Scales

Efforts to develop interventions to improve homework performance have been impeded by limitations in the measurement of homework performance. This study was conducted to develop rating scales for assessing homework performance among students in elementary and middle school. Items on the scales were intended to assess student strengths as well as deficits in homework performance. The sample included 163 students attending two school districts in the Northeast. Parents completed the 36-item Homework Performance Questionnaire — Parent Scale (HPQ-PS). Teachers completed the 22-item teacher scale (HPQ-TS) for each student for whom the HPQ-PS had been completed. A common factor analysis with principal axis extraction and promax rotation was used to analyze the findings. The results of the factor analysis of the HPQ-PS revealed three salient and meaningful factors: student task orientation/efficiency, student competence, and teacher support. The factor analysis of the HPQ-TS uncovered two salient and substantive factors: student responsibility and student competence. The findings of this study suggest that the HPQ is a promising set of measures for assessing student homework functioning and contextual factors that may influence performance. Directions for future research are presented.     

The neural regions sustaining episodic encoding and recognition of objects

In this functional MRI experiment, encoding of objects was associated with activation in left ventrolateral prefrontal/insular and right dorsolateral prefrontal and fusiform regions as well as in the left putamen. By contrast, correct recognition of previously learned objects (R judgments) produced activation in left superior frontal, bilateral inferior frontal, and right cerebellar regions, whereas correct rejection of distractor objects (N judgments) was associated with activation in bilateral prefrontal and anterior cingulate cortices, in right parietal and cerebellar regions, in the left putamen, and in the right caudate nucleus. The R minus N comparison showed activation in the left lateral prefrontal cortex and in bilateral cingulate cortices and precunei, while the N minus R comparison did not reveal any positive signal change. These results support the view that similar regions of the frontal lobe are involved in episodic encoding and retrieval processes, and that the successful episodic retrieval of newly learned objects is mainly based on a frontoparietal network.     

High impact running improves learning

Regular physical exercise improves cognitive functions and lowers the risk for age-related cognitive decline. Since little is known about the nature and the timing of the underlying mechanisms, we probed whether exercise also has immediate beneficial effects on cognition. Learning performance was assessed directly after high impact anaerobic sprints, low impact aerobic running, or a period of rest in 27 healthy subjects in a randomized cross-over design. Dependent variables comprised learning speed as well as immediate (1 week) and long-term (>8 months) overall success in acquiring a novel vocabulary. Peripheral levels of brain-derived neurotrophic factor (BDNF) and catecholamines (dopamine, epinephrine, norepinephrine) were assessed prior to and after the interventions as well as after learning. We found that vocabulary learning was 20 percent faster after intense physical exercise as compared to the other two conditions. This condition also elicited the strongest increases in BDNF and catecholamine levels. More sustained BDNF levels during learning after intense exercise were related to better short-term learning success, whereas absolute dopamine and epinephrine levels were related to better intermediate (dopamine) and long-term (epinephrine) retentions of the novel vocabulary. Thus, BDNF and two of the catecholamines seem to be mediators by which physical exercise improves learning.     

Data-driven type checking in open domain question answering

Many open domain question answering systems answer questions by first harvesting a large number of candidate answers, and then picking the most promising one from the list. One criterion for this answer selection is type checking: deciding whether the candidate answer is of the semantic type expected by the question. We define a general strategy for building redundancy-based type checkers, built around the notions of comparison set and scoring method, where the former provide a set of potential answer types and the latter are meant to capture the relation between a candidate answer and an answer type. Our focus is on scoring methods. We discuss nine such methods, provide a detailed experimental comparison and analysis of these methods, and find that the best performing scoring method performs at the same level as knowledge-intensive methods, although our experiments do not reveal a clear-cut answer on the question whether any of the scoring methods we consider should be preferred over the others.     

The transfer of movement sequences: effects of decreased and increased load

A number of recent experiments have demonstrated that a movement structure develops during the course of learning a movement sequence that provides the basis for transfer. After learning a movement sequence participants have been shown to be able to effectively produce the sequence when movement demands require that the sequence be rescaled in amplitude or produced with an unpractised set of effectors. The purpose of the present experiment was to determine whether participants, after learning a complex 16-element movement sequence with a 0.567-kg load, could also effectively produce the sequence when the load was decreased (0.0 kg) or increased (1.134 kg). The results indicated that participants were able to effectively compensate for decreased and increased load with virtually no changes in performance characteristics (displacement, velocity, acceleration, and pattern of element durations) while electromyographic (EMG) signals demonstrated that smaller (reduced load) or larger forces (increased load) were spontaneously generated to compensate for the change in load. The muscle activation patterns of the biceps and triceps as well as the level of coactivation appeared to be generally upscaled to generate and dissipate the changes in force requirement needed to compensate for the increased load.     

Equivalence of computerized and conventional versions of the Beck Depression Inventory-II (BDI-II)

This study examined the equivalence of the conventional and computerized versions of the Beck Depression Inventory-II (BDI-II), taking into account that computer aver-sion may negatively impact computer-administered BDI-II scores by elevating them. Participants were 180 psychology undergraduate students from a medium-sized midwestern university. Participants were divided into four experimental groups. Each group was administered the BDI-II twice in various combinations (conventional only, computerized only, conventional and computerized and vice versa). All participants completed measures of computer aversion and computer experience. Participants who received both versions of the BDI-II were also asked to specify their preference for method of administration. Independent samples t-test results indicated that the com-puterized and paper-and-pencil versions of the BDI-II may be considered equivalent in terms of measurement validity. Implications for future research are discussed. Portions of this article were presented at the 1999 meetings of the American Psychological Association, Boston. The authors thank Dr. Michael Granaas for statistical assistance with the Latin Squares analysis.