Poison-based avoidance learning with flavored or colored water in guinea pigs

Guinea pigs were fed a solution which had a distinctive taste or appearance and one hr later were made sick by an intraperitoneal injection of lithium chloride. Upon recovery from the effects of sickness the animals in Expt 1 showed aversions to a weak tasting, sour solution or to a strong tasting, sweet solution. Animals in Expt 2 formed aversions to tap water which had been colored either red or blue while those in Expt 3 formed aversions to tap water which had been presented in either red or blue drinking tubes. When, however, sickness was not contingent upon drinking a distinctive solution there was no sign of decreased consumption of the test solutions. The differences between the outcome of the Expts 2 and 3 and those typically found with rats can be explained by the fact that guinea pigs appear to use both taste and visual cues in food selection whereas rats primarily use only gustatory cues. Since vision in the guinea pig is no more acute than vision in rats and substantially more limited than vision in other animals who have formed aversions to visual cues, the results of Expts 2 and 3 also suggest that the ability to form poison-based aversions to visual cues is not totally dependent upon a highly developed visual system.     

Early learning as ontogenetic adaptation for ingestion by rats

Ontogenetic adaptation is an “ecological” concept in which mammalian maturation is seen as a coordinated sequence of specializations (stages) that enables the infant to survive within a sequence of distinct niches created by the parent(s) and the rest of the environment. Natural selection is presumed to operate at each point in development. The development of ingestive behavior in the rat pup as a series of ontogenetic adaptations enabling the infant while in the nursing niche to obtain and utilize mother's milk and progress gradually into the feeding niche in which a variety of solid foods must either be obtained or avoided is discussed. Data to show that learning is an integral part of these ontogenetic adaptations for ingestion are reviewed and interpreted. Preweanling rats that are capable of learning and remembering toxiphobic food aversions do not display an aversion to a flavor conditioned stimulus (CS) paired with illness if the CS is presented during suckling. In contrast, 20-day-old pups (weanlings) trained identically do show conditioned taste aversions under these conditions. A perspective of ontogenetic adaptations to this phenomenon of “blockade of toxiphobia by suckling” and its dissolution at weaning is applied. The generality of the blockade phenomenon and its mechanisms are explored, and it is shown that feeding experience regulates the stage-appropriate learning strategies used by the pups.     

Learning about water by hungry rats

In Experiments 1 and 2 hungry rats were trained in a straight alley with consistent food reward (FF), food and nonreward trials intermixed (FN), or food and water trials intermixed (FW). In Experiment 1 rats were tested with nonrewarded trials (extinction) and Groups FN and FW did not differ, both running faster then Group FF. In Experiment 2 rats were tested with consistent water reward, and Group FW ran faster then Group FN, which was superior to Group FF. In Experiment 3, one group of hungry rats was trained on a single alternating schedule of food and water in Phase 1 and was shifted to a single alternating schedule of food and nonreward in Phase 2 (Group FW); the second group (Group FN) received a single alternating schedule of food and nonreward in both phases. When Group FW was shifted to nonreward from water, performance to nonreward was temporarily disrupted. These results indicate that, contrary to previous conclusions, hungry rats can learn about water when drive is strong and food is received in the situation.     

Responsivity to stress in chronic posttraumatic stress disorder due to childhood sexual abuse

The purpose of this study was to investigate psychological, cardiovascular, and neuroendocrine reactivity to standardized stress tests (orthostatic challenge, Stroop Color Word Test) in drug-free adult women with chronic PTSD due to repetitive childhood sexual abuse. At baseline, the 11 patients showed significantly higher mean scores on the Symptom Check List-90 and the Profile of Mood States than 13 healthy female controls, whereas baseline cardiovascular or hormonal parameters showed no differences between the groups. Also, no significant differences were found between the two groups in cardiovascular and hormonal responsivity to the stress tests. Thus, in the presence of robust psychological differences, the patients with chronic PTSD due to childhood sexual abuse did not show alterations in baseline values of neurobiological parameters, nor did they react differently to a physical and mental stress test when compared to healthy controls.     

Increases in ethanol ingestion by young rats following interaction with intoxicated siblings: A review

Although there are a variety of animal models used in alcoholism research, there has been very little experimental investigation into possible environmental/experiential factors leading to an initial bout of alcohol ingestion. Adolescent alcohol abuse is a major problem in today's society and research is beginning to focus on the predisposing conditions toward alcohol consumption, particularly in this vulnerable age group. The results of recent research from our laboratory are reviewed in which voluntary ingestion of ethanol by preweanling and adolescent rats is increased following exposure to an intoxicated sibling. This paradigm centers on the notion that rodents, and perhaps other mammalian species as well, acquire information about foods to ingest based in part on interaction with a conspecific that has recently ingested a novel diet (e.g. Galef, 1981). Smelling food-derived cues on the breath of another animal is known to affect later food choice. The procedures described in this paper represent a potential new model for examining the effects of early exposure to ethanol through social interactions on the initiation of voluntary alcohol ingestion.     

Four-choice win-stay water escape acquisition by rats

Rats were capable of acquiring a four-choice win-stay water-escape task. While preventing access to the incorrect choice sections on information runs affected the first choices made on test runs, it did not affect rate of acquisition.     

Personality in rats and pain measures

The pain threshold of rats previously selected according to ambulation and defecation scores was assessed. Ss were 89 Sprague-Dawley rats aged 90 days. They were submitted to a low-frightening open-field (LFOF) test and 40 rats were selected on the grounds of extreme ambulation and defecation scores. The pain threshold was then assessed in 10 daily tests during 2 consecutive days. The mean of the 20 tests was used as the measure of the threshold and the mean of the two most extreme values was used as the measure for pain tolerance. The results obtained show that the pain thresholds of high-defecatory rats are significantly lower than those of low-defecatory rats. A similar relationship is found between low- and high-ambulatory rats, but the differences do not reach statistical significance. When the results of all 4 groups are compared the low-ambulatory and high-defecatory rats (introvert-neurotic) show the lowest threshold value, and the high-ambulatory and low-defecatory rats (extravert-stable) show the highest one which is significantly different from any other group. The results obtained with respect to the tolerance threshold, in spite of the lack of statistical significance, follow the same direction as those shown by the pain threshold.     

Brain transections selectively alter ingestion and behavioral activation in neonatal rats

Food-deprived neonatal rats actively ingest milk that is infused into their mouths through intraoral cannulas. This ingestion is accompanied by behavioral activation. The involvement of various brain regions in ingestion and activation was examined by making transections along the neuraxis from the olfactory bulbs to the anterior pons in 2-day-old rats. Following a 24-hr deprivation period, a series of oral milk infusions was given, and milk intake and activity were measured. Intake was severely reduced only in animals with diencephalic transections. Cuts in front of or behind the diencephalon resulted in normal or slightly decreased intake. In contrast, activity tended to decline as the level of the transection became more caudal. Thus ingestion and its accompanying behavioral activation could be separated neuroanatomically. These results suggest that two brain mechanisms are involved in the ingestive response of the infant rat, one in the diencephalon and another caudal to the mesencephalon. However, behavioral activation appears less discretely organized, involving most of the neuraxis.     

Tales of a successful memeplex: How the water wars in the everglades were changed into a comprehensive plan

In 2000, a $7.8 billion plan was signed to help create a feasible and innovative approach to the drying-up problem of the Florida Everglades. The Comprehensive Everglades Restoration Plan (CERP) would be the first time that parties that used to oppose each other regarding this issue will cooperate to reach a common goal. The article describes this intriguing process from a memetics perspective and shows that CERP spread fast because it reconciled different interests. Her research interests are safeguarding public values in privatized utility sectors. Her Ph. D. thesis Bridges and Watersheds was published in 2001 (Aksant, Amsterdam) and analyzes the shifting public private divide in water management under conditions of globalization. She is editor of the journals Bestuurswetenschappen and of Work & Emotion. Her latest book (with de Bruijn et al.) is Creating System Innovations. How Large Scale Transitions Emerge, Taylor and Francis, London (2004).     

《庄子》号《南华真经》源流考

《庄子》一书又称《南华真经》,然《庄子》何时有《南华真经》之称,学术界存在着不同的观点。传统的说法认为始于唐玄宗天宝元年。这种观点源于史书的记载。如《旧唐书·玄宗本纪》云:“(天宝元年)二月丁亥,上加尊号为开元天宝圣文神武皇帝。(天宝元年)二月丙申,庄子号为南华真     

Compliance with homework to employ self-instructions in controlling ice water pain: an analogue to counseling

40 women were taught to use self-statements to cope with pain caused by ice water. The trainer used four different strategies for reassigning a homework task of using self-statements to cope with pain produced by immersing one hand in ice water. The strategies were equally effective in eliciting compliance with the homework assignment.     

Made to escape: How the neoliberal rationality changed consumer escape

Current research on consumer escape is characterized by a paradox: when seeking to escape the structures, pressures, and obligations of modern life, consumers end up reinforcing the same structure that caused the desire to escape. We propose that this paradox can be explained by a connection between consumer escape and the neoliberal rationality, which is understood to focus on the creation of autonomous, ambitious, and aspiring individuals. Thus, in this article, we explain how the neoliberal rationality affects consumer escape. A three-year ethnography in a community of long-distance runners has enabled us to explain that the neoliberal rationality acts on consumer escape through three specific and interdependent dynamics: the community of performance, the entrepreneurial body, and the performance market. Together, those three dynamics change the nature of consumer escape experiences in our contemporary society, according to the main contribution of this research.