Emerging from imaginary time

Recent models in quantum cosmology make use of the concept of imaginary time. These models all conjecture a join between regions of imaginary time and regions of real time. We examine the model of James Hartle and Stephen Hawking to argue that the various no-boundary attempts to interpret the transition from imaginary to real time in a logically consistent and physically significant way all fail. We believe this conclusion also applies to quantum tunneling models, such as that proposed by Alexander Vilenkin. We conclude, therefore, that the notion of emerging from imaginary time is incoherent. A consequence of this conclusion seems to be that the whole class of cosmological models appealing to imaginary time is thereby refuted.We would like to thank Quentin Smith for helpful comments on an carlier version of this eassy. Read Guy gratefully acknowledges support from the M.J. Murdock Charitable Trust.     

Teacher escape,avoidance, and countercontrol behaviors: Potential resoponses to disruptive and aggressive behaviors of students with severe behavior disorders

We develop hypothese based on the research literature regarding behavioral responses to aversive stimuli. Specifically, escape, avoidance, and countercontrol responses are presented as teacher behaviors which may occur in the presence of disruptive and aggressive behaviors (aversive stimuli) which, in part, characterize many students with severe behavior disorders (SBD). The potential for teacher escape, avoidance, and countercontrol responses to the detrimental for both teachers and students is presented, as well as suggestions for addressing aversive behaviors of students in ways to reduce the potential detrimental impact.     

Brief-stimulus presentations on multiform tandem schedules

Three experiments examined the influence of a brief stimulus (a light) on the behavior of food-deprived rats whose lever pressing on tandem schedules comprising components of different schedule types resulted in food presentation. In Experiment 1, either a tandem variable-ratio variable-interval or a tandem variable-interval variable-ratio schedule was used. The variable-interval requirement in the tandem variable-ratio variable-interval schedule was yoked to the time taken to complete the variable-ratio component in the tandem variable-interval variable-ratio schedule, and the length of the variable-interval component in the latter schedule was yoked to the variable-ratio component in the former schedule. If a brief stimulus occurred following completion of the first component, then behavior was differentiated in the two components; subjects responded more quickly in the variable-ratio than in the variable-interval component. If the stimulus was removed, then response rate was determined by the nature of the final component. Similar results were obtained in Experiments 2 and 3 with the use of a three-component tandem variable-ratio variable-interval variable-ratio schedule or tandem variable-interval variable-ratio variable-interval schedule. Thus, a brief stimulus that was not explicitly paired with reinforcement engendered behavior typical of the component schedule preceding its presentation.     

What''s right and what''s wrong with transference theories

This paper examines the Transference Theory of causation, developed originally by Aronson (1971) and Fair (1979). Three difficulties for that theory are presented: firstly, problems associated with the direction of transference and causal asymmetry; secondly, the case of persistence as causation, for example where a body's own inertia is the cause of its motion; and thirdly the problematic notion of identity through time of physical quantities such as energy or momentum. Finally, the theory is compared with the Conserved Quantity Theory (Dowe 1992c), and it is shown that that account embodies the modifications that the transference theory needs to adopt.     

Differential gender effects of exposure to rap music on African American adolescents' acceptance of teen dating violence

The purpose of the present study was to assess the effects of exposure to nonviolent rap music on African American adolescents' perceptions of teen dating violence. African American male and female subjects were exposed to nonviolent rap videos (which contained images of women in sexually subordinate roles) or they saw no videos. They read a vignette that involved teen dating violence perpetrated by a male. The results indicated that there was a significant interaction between gender and video exposure. More specifically, acceptance of the use of violence did not vary as a function of exposure for male subjects. Conversely, female subjects who were exposed to the videos showed greater acceptance of the violence than females who were not exposed. Possible basis and implications for these findings are discussed.To whom reprint requests should be addressed at Department of Psychology, The University of North Carolina at Wilmington, 601 South College Road, Wilmington, NC 28403-3297.     

Young people's career choices and careers guidance action planning: A case-study of training credits in action

A specific careers guidance action plan, used in conjunction with one of the original training credits pilot schemes, is investigated. Analysis revealed tensions between the pragmatically rational way in which young people reported making career decisions and the technically rational system of guidance built into the design of the scheme. These tensions created operational difficulties for careers officers, and raise important issues for further debate about the nature of careers education and guidance     

Effect of local context of responding on human judgment of causality

Two experiments examined the effect of various relationships between a response (pressing the space bar of a computer) and an outcome (a triangle flashing on a screen) on judgments of the causal effectiveness of the response. In Experiment 1, when responses were required to be temporarily isolated from each other prior to an outcome, ratings of the causal effectiveness of the responses were higher than in a condition in which the probability of an outcome following a response was the same but in which no temporal isolation was required. In Experiment 2, when a number of responses were required to be emitted temporally close to the outcome, ratings of the causal effectiveness of the responses were lower than in a condition in which the probability of an outcome following a response was the same but in which no temporal proximity was required. These results suggest that, in addition to the overall probability that an outcome will follow a response, the local context of responding at the time an outcome is presented is critical in influencing ratings of causal effectiveness.     

Knowers talking about the known: Ecological realism as a philosophy of science

This Paper is Dedicated to Marjorie Grene, in Honor of her 80th Birthday     

What makes targets redundant?

Two letter-classification experiments that investigated target-redundancy effects on reaction time (RT) were conducted. Both experiments were replicated with choice reaction time (CRT) and go/no-go (GNG) procedures. In each experiment, there were two single-target conditions, one with a noise letter and one without. In one experiment, the letter classes were two letters that could be of either case. In the second experiment, each class consisted of two different capital letters. In both experiments, there were two redundant-targets conditions, one with identical targets and one with the different members of a class. In both of the GNG experiments, redundancy gains were obtained comparing the different-targets condition with the no-noise, single-target condition. Redundant stimuli are ones that lead to the same response. Visually different stimuli may be processed in parallel and jointly activate a response. GNG procedures are more sensitive than CRT in the investigation of redundancy effects.     

Effect of enriched (complex) environment on nerve conduction velocity: New data and review of implications for the speed of information processing

Extensive research with genetically heterogeneous rats and other mammals haa shown many effects of environmental enrichment (EE; comparing complex, stimulating environment with simple environment) on brain and behavior. Increased nerve conduction velocity (NCV) in brain nerve pathways is one of these effects. Research with a genetically heterogeneous mouse strain (HS) also strongly suggests that increased stimulation or usage increases peripheral NCV (PNCV) and this study on 54 HS mice confirms this. Human data also indicate that increased activity increases PNCV. Therefore, both brain NCV and PNCV appear to increase after EE. Since extensive human data indicate that the speed of information processing (SIP) is positively correlated with intelligence level, and brain NCV should be a component of SIP, these results suggest a role, at the physiological level, for EE (or deprivation) in affecting measured intelligence.