EMG waveform duration: A validation method for the surface electromyogram

The electromyogram (EMG) recorded with surface electrodes was examined using a triggered oscilloscope technique. When all but the high-amplitude waveforms in a given segment of activity were excluded from analysis, it was found that the duration of the remaining waveforms was specific to the muscle that produced them. That is, waveforms of a given duration were recorded whenever conventional indices-observable contraction, joint movement. needle recordings-showed activity in a specific muscle. This led to the suggestion that waveform duration might be used to validate the surface EMG. The suggestion. which is limited by the need to control posture and electrode placement, both of which may influence waveform duration, was illustrated in application to psychological research.     

The semantics ofR4

The LogicR4 is obtained by adding the axiom (A vB(AvB) to the modal relevant logicNR. We produce a model theory for this logic and show completeness. We also show that there is a natural embedding of a Kripke model forS4 in eachR4 model structure.We are indebted to several people for discussions relating to the topic of this paper, in particular, Kit Fine, John Slaney, J. M. Dunn, Jacques Riche, M. A. McRobbie, and Jill LeBlanc. We would also like to thank the Automated Reasoning Project for material assistance. Mares would like to thank The Social Sciences and Humanities Research Council of Canada for fellowships 456-89-0128 and 457-90-0081, which supported him while writing this paper.     

Schedule-induced defecation by rats during ratio and interval schedules of food reinforcement.

Lever pressing in rats was maintained by continuous and intermittent schedules of food while defecation was monitored. In Experiment 1, reinforcement densities were matched across variable-ratio and variable-interval schedules for three pairs of rats. Defecation occurred in all 3 rats on the variable-ratio schedule and in all 3 rats on the yoked variable-interval schedule. In Experiment 2, fixed-ratio and fixed-interval schedules with similar reinforcement densities maintained lever pressing. Defecation occurred in 3 of 4 rats on the fixed-ratio schedule and in 4 of 4 rats on the fixed-interval schedule. Almost no defecation occurred during continuous reinforcement in either experiment. These results demonstrate that defecation may occur during both ratio and interval schedules and that the inter-reinforcement interval is more important than the behavioral requirements of the schedule in generating schedule-induced defecation.     

Toward a Process Analysis of Emotions: The Case of Surprise

Based on an earlier model of the processes elicited by surprising events, the present studies provide evidence for one of these processes, the evaluation of the surprising event's relevance for ongoing activities (action-relevance check). The central prediction tested was that, if unexpected events elicit among other processes an action-relevance check, then response delay on a concurrent task will be more pronounced in a condition where this process is more elaborate and hence takes more time. In accord with this prediction, Experiment 1 found that an unexpected appearance change of the imperative stimulus in a choice reaction time (RT) task caused greater response delay than an equivalent appearance change of a distractor stimulus. Experiment 2 replicated this finding and tested several additional predictions that concerned the effects on response delay of a second appearance change of either the imperative or the distractor stimuli. These predictions, which were also mostly confirmed, were derived by combining the logic underlying the first study with the assumption that once made, appraisals of unexpected events are stored as part of the situational schema and are reused when the same or similar events reoccur leading to an abbreviation of appraisal processes. Experiment 3 once more replicated the basic finding of the previous studies and ruled out a possible alternative explanation. It is suggested that the proposed RT method of process verification may be of broader interest as a tool to study appraisal processes in emotion.     

Ethics, theism and metaphysics: An analysis of the theocentric ethics of James Gustafson

Modern ethics has been shaped by two dominant philosophical assumptions: (1) that there can be no theoretical knowledge of God, i.e., denial of metaphysics, and (2) that moral claims can be redeemed independently of theistic affirmations, i.e., morality does not require theism. These assumptions have influenced much of modern theological ethics. Yet, insofar as theological ethics accepts that morality does not require any explicit or implicit religious beliefs, it affirms that a secularistic morality is possible. But this affirmation is directly at odds with the essence of theism, namely, that God is the source and end of all things, including the moral life. By accepting the dominant consensus, therefore, theological ethics undermines its fundamental theistic claim. Focusing on James Gustafson's theocentric ethics, I seek to show the price that theological ethics pays for subscribing to the dominant consensus. I argue that: (1) Gustafson embraces an inconsistent self-understanding, which undermines his theocentric claim, (2) this is due to his dismissal of metaphysics, and (3) his theocentric ethic would be more compelling if formulated in terms of Whitehead's process metaphysics.