Relationship between vomiting and taste aversion learning in the ferret: studies with ionizing radiation, lithium chloride, and amphetamine.

The relationship between emesis and taste aversion learning was studied in ferrets (Mustela putorius furo) following exposure to ionizing radiation (50-200 cGy) or injection of lithium chloride (1.5-3.0 mEq/kg, ip). When 10% sucrose or 0.1% saccharin was used as the conditioned stimulus, neither unconditioned stimulus produced a taste aversion, even when vomiting was produced by the stimulus (Experiments 1 and 2). When a canned cat food was used as the conditioned stimulus, lithium chloride, but not ionizing radiation, produced a taste aversion (Experiment 3). Lithium chloride was effective in producing a conditioned taste aversion when administration of the toxin was delayed by up to 90 min following the ingestion of the canned cat food, indicating that the ferrets are capable of showing long-delay learning (Experiment 4). Experiment 5 examined the capacity of amphetamine, which is a qualitatively different stimulus than lithium chloride or ionizing radiation, to produce taste aversion learning in rats and cats as well as in ferrets. Injection of amphetamine (3 mg/kg, ip) produced a taste aversion in rats and cats but not in ferrets which required a higher dose (> 5 mg/kg). The results of these experiments are interpreted as indicating that, at least for the ferret, there is no necessary relationship between toxin-induced illness and the acquisition of a CTA and that gastrointestinal distress is not a sufficient condition for CTA learning.     

Nonverbal indicators of Affect and Deception in an Interview Setting1

A study was conducted to identify codes of nonverbal behavior which could be used by interviewers in a standard field interview to systematically assess deception and emotional states of respondents. Ten male and 10 female subjects were interviewed on topics that had been pretested to arouse in them pleasant involvement, passivity, and unpleasant involvement. Subjects were also instructed to lie to the interviewer on issues of importance to them. Eye contact was measured by observation through a one-way mirror. Smiles, gestures, self-manipulations and postural shifts were scored from videotapes of the interview. The most distinctive patterns of nonverbal cues occurred with unpleasant-involvement and deception questions. The former state was characterized by increases in smiling, self-manipulations, and postural shifts. Deception responses were marked by decreases in smiling and increases in self-manipulations and postural shifts. Results also suggested that eye contact functioned as an intensifier of affect.     

Switching attention between the ears to monitor tones Nigel Harvey

Alternating dichotic presentation of tones was compared with monaural presentation in two different perceptual tasks. When Ss were asked to detect higher frequency target tones in fists of six background tones, they missed less than 5%. However, when the presentation was fast (10/sec) and the tones alternated dichotically, Ss reported “hearing” only three or four tones. In two further experiments, Ss were asked to judge the number of tones or to report their spatial and temporal positions; these tasks were much less accurately performed, for the dichotic lists, than the target detection task. The differing effects of switching rate on these tasks are discussed in relation to the types of processing they require.     

A continuous interference-filter monochromator

An inexpensive continuous interference-filter monochromator is described.     

An automated swim alley for small animals: II. Training and procedures

Experiments were conducted to establish training procedures and testing conditions that produce uniform and reliable swimming performance of rats in an automated swim alley. Data are given on the effect of water temperature and of platform rest interval on swimming speeds. In this system, rats will swim intermittently for as long as 24 h for a distance of more than 7 km.     

Are absolute frequencies,relative frequencies,or both effective in reducing cognitive biases?

Biases in probabilistic reasoning are affected by alterations in the presentation of judgment tasks. In our experiments, students made likelihood judgments that an event was produced by various causes. These judgments were made in terms of probability, relative frequency or absolute frequency on a full or a pruned list of causes. When they had little personal experience of the event (causes of death), the pruning bias was smaller with relative frequencies than with absolute frequencies or probabilities. When they had more personal experience of the event (missing a lecture), the bias was less with both types of frequency than with probability but still lowest with relative frequency. We suggest that likelihood information is usually stored as relative frequencies when it has been obtained from public sources but that it is based on event counts when it is derived from personal experience. Copyright © 2000 John Wiley & Sons, Ltd.     

A meta-analysis of the relationship between moral disengagement and bullying roles in youth

Over the last several years, researchers have become increasingly interested in the influence of moral factors on bullying behaviors. This is the first meta-analytic review to exclusively examine the relationship between moral disengagement (MD) and the key bullying roles of bully, victim, defender, and bystander. Forty-seven independent samples examining a total of 43,809 children/adolescents (aged 7–19) were included in this meta-analysis. Results indicated a positive relationship between MD and bullying (r = 0.31; 95% CI [0.27, 0.34]), MD and victimization (r = 0.08; 95% CI [0.05, 0.12]), and a negative relationship between MD and defending (r = −0.11; 95% CI [−0.17, −0.04]). No significant relationship was found for MD and bystanding behavior. Moderators of bullying type (traditional vs. cyberbullying), reporting type (self vs. peer report), age, and gender were included in the analyses. The results are discussed in the context of relevant literature with particular emphasis on the importance of distinguishing between guilty and unconcerned bystanders, and the significant overlap between bullying and victimization in the cyber context.