Three experiments used an appetitive Pavlovian conditioning procedure to investigate the ability of the context to generate excitation. Discrete stimuli (CSs) signalling food unconditioned stimuli (USs) were used to decrease contextual conditioning. Detailed observations of the behaviours of rats during and immediately preceding the presentation of CSs, and in an event-free period were analysed. Experiment 1 showed that a discrete visual CS was able to interfere with contextual conditioning because it was a more efficient cue for food than the context. Experiment 2 found that an auditory CS could reduce contextual conditioning in a similar manner but the topography of responding during the event-free period was specific to the modality of the CS. Experiment 3 demonstrated that signal-appropriate responding during the event-free period occurred only if the CS was a signal for reinforcement.
Delayed extinction of electrodermal conditioned responses following instructed rehearsal of Pavlonian contingenciesGino, Antonio. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 33-36).
Mignault, Alain, 1962-
The history of classical conditioning is summarized. The contributions and weaknesses of several earlier models of classical conditioning are studied. Two new neuronal models are proposed. The first, called the delay-producing connections (or DPC) model, is an extension of the Klopf (1988) and Sutton & Barto (1981) models. The DPC model makes two contributions: (1) it represents the trace of each conditioned stimuli (CS) by differential equations; and (2) it replaces each CS in the activation rule with a trace of the relevant CS. A method is suggested to measure the trace of a CS. The second model, called the adaptive delays (or AD) model, is proposed as an extension of the DPC model to account for the phenomenon of inhibition of delay. Both models reproduce the shape of a CR, the curve of efficacy of conditioning as a function of the interstimulus interval (ISI), the dependence of the optimal ISI on CS duration, the extinction of a CR (even for long lasting CSs as opposed to Klopf's (1988) model), and several other properties of classical conditioning.
Soanes, Grant Paul
No description available.
(has links) (PDF)
Thesis (B.A. (Hons.))--University of Queensland, 2005. / Includes bibliographical references.
Hodes, Robert Louis,
Thesis (Ph. D.)--University of Wisconsin--Madison, 1981. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 147-155).
Reichel, Carmela M.
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008. / Title from title screen (site viewed Mar. 31, 2009). PDF text: ix, 94 p. : ill. ; 910 K. UMI publication number: AAT 3330851. Includes bibliographical references. Also available in microfilm and microfiche formats.
Michel, Sergio B. (Sergio Barboza)
According to Deikman (1966), meditation (defined as a training to sustain attention) has a deautomatizing effect. This ascertion was utilized in the present study as a departure point and explored within an information processing framework for classical conditioning. A sample of 48 college students was selected and randomly assigned to four conditions with different instructional sets involving allocation of attention during a classical conditioning background situation. The basic hypothesis of the study was that provided arousal factors were controlled, focusing of attention upon internal stimulation (i.e. breathing) could delay or attenuate the affect of conditioning, habituation and extinction as compared with instructions to externally allocate attention (on the CS and US). A secondary hypothesis predicted that for subjects under switching conditions changing from internal to external allocation and vice versa would produce a more pronounced extinction pattern as compared with subjects under non—switching conditions.
Holahan, Matthew R.
Research over the past several decades has revealed that the amygdala is involved in aversive, or fear, conditioning. However, the precise nature of this involvement remains a matter of debate. One hypothesis suggests that disrupting amygdala function eliminates the storage of memories formed during aversive conditioning, eliminating the production of internal responses that alter the expression of observable behaviors. Alternatively, lesions or inactivation of the amygdala may impair the modulation of memories in other brain regions and disrupt the ability to perform certain observable behaviors. The experiments reported in the present thesis examined these arguments by making multiple behavioral measures during exposure to unconditioned (US) or conditioned (CS) aversive cues. Amygdala activity was inferred from changes in c-Fos protein expression or activity was temporarily suppressed with muscimol injections. The relationship between the behavioral measures and the role of the amygdala in producing them was examined. Amygdala neurons expressing the c-Fos protein tracked exposure to the US and CS but did not coincide with expression of freezing. Temporary inactivation of the amygdala with muscimol injections before presentation of the US or exposure to the CS attenuated the expression of freezing and active place avoidance; two incompatible behaviors. Finally, temporary inactivation of amygdala activity blocked freezing, place avoidance, and memory modulation produced by the same posttraining exposure to an aversive CS. Since amygdala activation alone was not sufficient to produce freezing and inactivation of the amygdala eliminated freezing, place avoidance, and memory modulation, the results cannot be interpreted as reflecting a direct role for the amygdala in production of observable behaviors. The results also preclude the idea that memory modulation is the only function of the amygdala. Rather, the results of all three studies suggest that the amygdala stores an aversive representation of the US which promotes the expression of various behaviors, possibly through the production of internal responses reflecting an aversive affective state.
Jones, Dirk Andrew,
Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 128-140). Available also in a digital version from Dissertation Abstracts.
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