Contribution of conditioned opioid analgesia to the shock-induced associative US-preexposure deficit     

Louis D. Matzel  Steve C. Hallam  Ralph R. Miller 《Learning & behavior》1988,16(4):486-492

The modulatory effect of conditioned opioid analgesia on learning in the US-preexposure paradigm was examined in three experiments using water-deprived rats. In Experiment 1, it was found that tailflick latencies increased immediately after the rats were exposed to a context in which footshock had previously been administered. Prolonged nonreinforced exposure to the context attenuated this analgesia. Experiment 2 tested the possibility that the effectiveness of CS-US pairings in an excitatory context might be reduced by a conditioned analgesic response that lessens the perceived intensity of the US. Administration of the opiate antagonist naloxone prior to CS-US pairings in the excitatory context reduced the US-preexposure deficit—that is, the retarded response to the CS—but did not eliminate it, suggesting that part of the observed deficit resulted from conditioned activation of the endogenous opioid system. In Experiment 3, it was found that exposure to the excitatory context immediately prior to a CS-US pairing in an associatively neutral context resulted in a conditioned response deficit, indicating that the analgesia elicited by the excitatory context was sufficient to reduce US effectiveness. In combination with other recent reports, these results suggest that the associative deficit resulting from preexposure to a shock US may, in certain instances, represent the sum of several different associative processes.  相似文献   

Temporal encoding in trace conditioning     

Robert P. Cole  Robert C. Barnet  Ralph R. Miller 《Learning & behavior》1995,23(2):144-153

Conditioned lick suppression in rats was used to explore the role of timing in trace conditioning. In Experiment 1, two groups of rats were exposed to pairings of a CS (CS1) with a US, under conditions in which the interstimulus interval (ISI) that separated CS1 offset and US onset was either 0 or 5 sec. Two additional groups were also exposed to the same CS1→US pairings with either a 0 or a 5-sec ISI, and then received “backward” second-order conditioning in which CS1 was immediately followed by a novel CS2 (i.e., CS1→CS2). A trace conditioning deficit was observed in that the CS1 conditioned with the 5-sec gap supported less excitatory responding than the CS1 conditioned with the 0-sec gap. However, CS2 elicited more conditioned responding in the group trained with the 5-sec CS1-US gap than in the group trained with the 0-sec CS1-US gap. Thus, the CS1-US interval had inverse effects on first- and second-order conditioned responding. Experiment 2 was conducted as a sensory preconditioning analogue to Experiment 1. In Experiment 2, rats received the CS1?CS2 pairings prior to the CS1→US pairings (in which CS1 was again conditioned with either a 0 or a 5-sec ISI). Experiment 2 showed a dissociation between first- and second-order conditioned responding similar to that observed in Experiment 1. These outcomes are not compatible with the view that differences in responding to CSs conditioned with different ISIs are mediated exclusively by differences in associative value. The results are discussed in the framework of the temporal coding hypothesis, according to which temporal relationships between events are encoded in elementary associations.  相似文献   

ODS Network ‐ International School Networking     

Ralph Ballier  Klaus Füller 《Educational Media International》2013,50(3):126-130

Abstract

The initiative ‘Offenes Deutsches Schul‐Netz’ (ODS) ‐ The Open German School Network ‐ sees itself as a joint cover for school networking in Germany. In this article, we give an insight into the very successful ideas on which ODS is based. Practically every computer‐mediated communication between schools in Germany and abroad is transmitted on the basis of agreements by the ODS with various servers. We describe, briefly, how we imagine networking between schools in future.  相似文献   

What succeeds with an audience is bad     

Ralph Waldo Emerson Thoreau 《Quarterly Journal of Speech》2013,99(1)

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Changes in Relationship Between Teachers and Pupils Necessitated by a New Emphasis in Religious Education     

Ralph P. Bridgman 《Religious education (Chicago, Ill.)》2013,108(4):289-291

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On the electrical and anomalous scattering of mesotrons     

Ralph P. Shutt 《Journal of The Franklin Institute》1942,234(2):195-196

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“Maybe so — but count me out”     

Ralph N. Schmidt 《Communication quarterly》2013,61(2):4-5

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An activity‐centered alternative to teacher education     

Ralph Erickson 《The Teacher Educator》2013,48(1):5-7

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Modern poetry and a Kat called Krazy     

Ralph Pomeroy 《Communication quarterly》2013,61(3):14-15

This essay uses the nature of the genre of apologia as outlined by speech communication scholars as a framework to examine Richard Nixon's apology to the nation on the occasion of his resignation. Mr. Nixon conformed well to the requirements of the subgenre, explanation, but erred in areas not suggested in contemporary writings on apologia. The gravity of Nixon's misdeeds and the incongruity of his admission of guilt overshadowed the strategy of explanation which he employed to defend himself.  相似文献   

Effects of communication load,affect, and anxiety on the performance of information processing tasks     

Paul E. King  Ralph R. Behnke 《Communication quarterly》2013,61(1):74-84

Discrepant claims have been advanced regarding the impact of communication load on information processing. Recent research and theory suggest that an increase in speed results in decreased response accuracy during comprehensive listening. However, despite indicated relationships between cognitive and affective learning, few investigators have explored the impact of communication load on affective responses. In the present study, the impact of communication load on affect, state anxiety, and several types of information processing performance is demonstrated. Moreover, a significant relationship was found between task‐directed affect and three modes of processing. Practical and theoretical implications of these findings are discussed.  相似文献