Classical aversive conditioning of heart rate in curarized rats at different blood gas levels

In an effort to examine whether normal blood gas tensions were essential for conditioning, paralyzed rats received a classical aversive heart rate (HR) conditioning session while respirated at different peak expired CO₃ values. After the session, arterial blood was drawn for analysis. That peak expired CO₂ was effective in manipulating Pco₂ was indicated by a significant correlation (r = 0.594, df = 17, P < 0.05). In addition, only rats with blood gas values similar to those of anesthetized controls displayed a discriminated HR CR. These animals also had lower baseline HRs and greater HR variability. Further, 7 of the 9 rats with normal blood gas values were respirated at peak expired CO₂ values from 5.0–5.1 per cent, and no animal ventilated within this range displayed abnormal values. These findings suggest that previous difficulties in obtaining classical and operant conditioning in paralyzed animals may, in part, be attributable to inadequate ventilation.     

Fibromyalgia: the role of sleep in affect and in negative event reactivity and recovery

OBJECTIVE: Fibromyalgia (FM) syndrome is a chronic pain condition characterized by diffuse muscle pain, increased negative mood, and sleep disturbance. Until recently, sleep disturbance in persons with FM has been modeled as the result of the disease process or its associated pain. The current study examined sleep disturbance (i.e., sleep duration and sleep quality) as a predictor of daily affect, stress reactivity, and stress recovery. DESIGN AND MEASURES: A hybrid of daily diary and ecological momentary assessment methodology was used to evaluate the psychosocial functioning of 89 women with FM. Participants recorded numeric ratings of pain, fatigue, and positive and negative affect 3 times throughout the day for 30 consecutive days. At the end of each day, participants completed daily diary records of positive and negative life events. In addition, participants reported on their sleep duration and sleep quality each morning. RESULTS: After accounting for the effects of positive events, negative events, and pain on daily affect scores, it was found that sleep duration and quality were prospectively related to affect and fatigue. Furthermore, the effects of inadequate sleep on negative affect were cumulative. In addition, an inadequate amount of sleep prevented affective recovery from days with a high number of negative events. CONCLUSIONS: These results lend support to the hypothesis that sleep is a component of allostatic load and has an upstream role in daily functioning.     

Teaching scared: pre-service teacher appraisals of racial stress,socialization and classroom management self-efficacy

Social Psychology of Education - The fears of pre-service teachers, particularly Teach for America (TFA) teachers. about working in urban classroom settings are framed as racial stress. Racial...     

The priority of primary process categorizing: experimental evidence supporting a psychoanalytic developmental hypothesis

Earlier work has provided experimental evidence for the existence of the primary and secondary process mental organization posited by Freud and has demonstrated that primary process effects are the more active unconsciously (Brakel et al. 2000). Primary and secondary processes were assessed by a categorization test in which qualitatively different principles could be used. In new experiments using the same stimuli, another significant implication of Freud's model was tested: that primary process mental organization has developmental priority. In these experiments, which studied 559 participants ranging in age from 3 to 80, it was found (1) that primary process mentation predominates in preschoolers; (2) that it is not until around age 7 that primary process organization is supplanted by secondary process organization; and (3) that after age 7 the predominance of secondary process organization remains remarkably stable throughout the life span.     

Behavioral effects of chronic melatonin and pregnenolone injections in a myelin mutant rat (taiep)

The taiep (tremor, ataxia, immobility, epilepsy, and paralysis) myelin mutant displays a number of locomotor deficits. Taiep rat gait is characterized by shorter stride and step lengths as well as by larger stride widths. Thirty-day-old taiep mutants were placed under a regimen of daily hormone injections for 60 days. Animals in Condition 1 received melatonin, those in Condition 2 received pregnenolone sulfate, and those in a third control condition received injections of saline. Following the injections, each taiep mutant's gait was analyzed. The animals that received melatonin and pregnenolone displayed significantly larger stride and step lengths than did the controls. In addition, the animals that received hormones displayed shorter stride widths than did the controls. These experimental effects are consistent with a normalization of gait. Possible cellular mechanisms of this behavioral effect are discussed.     

The natural history of gambling and drinking problems among casino employees

From an eligible population of 9,943 casino employees, 6,067 volunteered to participate in this study. Of this sample, 1,176 provided data at 3 observation points approximately 12 months apart. Using the South Oaks Gambling Screen (SOGS; H. R. Lesieur & S. B. Blume, 1987) and the CAGE (J. A. Ewing, 1984) questionnaire, the authors prospectively examined the prevalence and patterns of alcohol and gambling problems among those employees. Among the casino employees with gambling and drinking problems, a segment displayed the capacity to diminish those problems even when the difficulties had reached disordered levels. The authors also examined the comorbidity of gambling and drinking as well as the relationships among changes in SOGS scores and CAGE scores and changes in demographic and biological variables. The women were more likely to decrease their problem-drinking scores, but not their gambling scores, when compared with the men. In addition, 2 key variables (i.e., disabling depression and dissatisfaction with one's personal life) emerged as predictors of transitions to healthier levels of disordered gambling. The authors cautiously suggest, in light of the results taken together, that more fluctuation is associated with gambling and drinking problems than previously thought and that the conventional wisdom about disordered gambling as "always progressive" needs reconsideration.     

Dissociation of explicit and implicit timing in repetitive tapping and drawing movements

Four experiments explored the hypothesis that temporal processes may be represented and controlled explicitly or implicitly. Tasks hypothesized to require explicit timing were duration discrimination, tapping, and intermittent circle drawing. In contrast, it was hypothesized that timing control during continuous circle drawing does not rely on an explicit temporal representation; rather, temporal control is an emergent property of other control processes (i.e., timing is controlled implicitly). Temporal consistency on the tapping and intermittent drawing tasks was related, and performance on both of these tasks was correlated with temporal acuity on an auditory duration discrimination task. However, timing variability of these 3 tasks was not correlated with timing variability of continuous circle drawing. These results support the hypothesized distinction between explicit and implicit temporal representations.     

The Fisher-Pitman permutation test: an attractive alternative to the F test

The Fisher-Pitman permutation test is shown to possess significant advantages over conventional alternatives when analyzing differences among independent samples with unequal variances.