Limbic hypertension induced by stress and septal stimulation

For this study, it was postulated that hypertension of emotional origin is generated within the limbic system. To validate this thesis, septal induced blood pressure elevations were combined with a stressful experience in adult rats (spontaneously hypertensive and Wistar Kyoto rats). Stress consisted of intermittent confinement in a plexiglass tube. The results revealed that hypertension induced by electric stimulation of the septum during the stressful state could subsequently be elicited by the stressful state alone, without electric stimulation of the septum. It was postulated that the cortically modulated stress circuit converged with the electrically activated limbic pressor circuit at the level of the septum. This convergence resulted in the formation of one cortico-limbic circuitry which could be activated by stress alone. This underlying mechanism may be considered as a model of neural sensitization in the production of stress-induced limbic hypertension.     

Adjunctive brainstem behaviors in the rat

Adjunctive behaviors refers to behaviors that are “out of context” and/or excessive in amount. The terminology was first used for unexplained behaviors associated with food pellet ratio contingencies in food deprived rats (Falk, 1971). Clinically, unrelated and complex excessive behaviors were also noted with brainstem and diencephalic discharges (Andy, 1986, 1989 and 1995; Andy and Jurko, 1986). The objective of this study was to develop a model of brainstem generated adjunctive behaviors in the rat. Method: Sixty-one adult rats were used. Kindling was induced by mechanical and DC electrical perturbations in the midbrain. Nine different treatment groups were established in which lesions and drugs were used separately and in different combinations. Cocaine was used to accentuate, and dextrorphan to attenuate the kindling process. Behaviors were visually analyzed and recorded by video camera; they were not quantified. DC stimulation and EEGs were done with Grass instruments. Recording and stimulation sights were verified histologically. Results: A total of 45 different behaviors were elicited. DC stimulation kindled subjects had significantly more behaviors than did electrode insertion alone and cocaine alone. However, cocaine combined with DC stimulation increased the number and intensity of the kindled behaviors. Dextrorphan tended to facilitate catatonic and sleep states. Behaviors occurred randomly and were unrelated, even when they occurred in clusters. The behaviors were associated with four abnormal EEG discharge patterns. Conclusion: We speculate that brainstem behaviors are innate adjunctive drives that are generated in the brainstem reticular formation. They are monitored by the cortex and partially modified by environmental and cortical inputs.     

Test–retest reliability and task order effects of emotional cognitive tests in healthy subjects

Little is known of the retest reliability of emotional cognitive tasks or the impact of using different tasks employing similar emotional stimuli within a battery. We investigated this in healthy subjects. We found improved overall performance in an emotional attentional blink task (EABT) with repeat testing at one hour and one week compared to baseline, but the impact of an emotional stimulus on performance was unchanged. Similarly, performance on a facial expression recognition task (FERT) was better one week after a baseline test, though the relative effect of specific emotions was unaltered. There was no effect of repeat testing on an emotional word categorising, recall and recognition task. We found no difference in performance in the FERT and EABT irrespective of task order. We concluded that it is possible to use emotional cognitive tasks in longitudinal studies and combine tasks using emotional facial stimuli in a single battery.     

The Effect of the Accountability Variables of Responsibility,Openness, and Answerability on Authentic Leadership

One salient aspect of authentic leadership is the possibility that it can be developed (Walumbwa, Avolio, Gardner, Wernsing, &; Peterson, 2008 Walumbwa, F. O., Avolio, B. J., Gardner, W. L., Wernsing, T. S., &; Peterson, S. J. (2008). Authentic leadership: Development and validation of a theory-based measure. Journal of Management, 34(1), 89–126. doi:10.1177/0149206307308913[Crossref], [Web of Science ®] , [Google Scholar]). However, the relative paucity of research on authentic leadership as a dependent variable needs to be addressed. The purpose of this cross-sectional quantitative study is to examine the three factors of accountability: (a) responsibility, (b) openness, and (c) answerability (Wood &; Winston, 2007 Wood, J. A., &; Winston, B. E. (2007). Development of three scales to measure leader accountability. Leadership &; Organization Development Journal, 28(2), 167–185. doi:10.1108/01437730710726859[Crossref] , [Google Scholar]) as antecedents to authentic leadership. Using survey results from a sample of full-time employees at six faith-based institutions of higher education in the United States, a predictive relationship was investigated through hierarchical regression analysis. The results indicated that the variables of responsibility, openness, and answerability predict the perception of authentic leadership.     

Long-term persistence of sort strategy in free classification

Two free classification experiments that investigate the persistence of sort strategy are reported. Participants tend to persist with their initial categorization type (family resemblance or unidimensional) for the remaining sorts, overriding the effects of otherwise influential stimulus properties. Sort type was found to persist even after a one-week delay. Stimulus-driven models of free classification (e.g., the SUSTAIN model, [Love, B. C., Medin, D. L., & Gureckis, T. M. (2004). SUSTAIN: A network model of category learning. Psychological Review, 111, 309-332]) cannot predict the sort type persistence effects we observe, but they are naturally accounted for by theories that posit strategic selection of a problem-solving strategy (e.g., Hypothesis theory, [Levine, M. (1971). Hypothesis theory and nonlearning despite ideal S-R-reinforcement contingencies. Psychological Review, 78, 130-140]).     

Brain Recording,Mind-Reading,and Neurotechnology: Ethical Issues from Consumer Devices to Brain-Based Speech Decoding

Science and Engineering Ethics - Brain reading technologies are rapidly being developed in a number of neuroscience fields. These technologies can record, process, and decode neural signals. This...