Eye movement during recall reduces objective memory performance: An extended replication.

Eye Movement Desensitization and Reprocessing (EMDR) therapy for posttraumatic stress disorder involves making eye movements (EMs) during recall of a traumatic image. Experimental studies have shown that the dual task decreases self-reported memory vividness and emotionality. However valuable, these data are prone to demand effects and little can be inferred about the mechanism(s) underlying the observed effects. The current research aimed to fill this lacuna by providing two objective tests of memory performance. Experiment I involved a stimulus discrimination task. Findings were that EM during stimulus recall not only reduces self-reported memory vividness, but also slows down reaction time in a task that requires participants to discriminate the stimulus from perceptually similar stimuli. Experiment II involved a fear conditioning paradigm. It was shown that EM during recall of a threatening stimulus intensifies fearful responding to a perceptually similar yet non-threat-related stimulus, as evidenced by increases in danger expectancies and skin conductance responses. The latter result was not corroborated by startle EMG data. Together, the findings suggest that the EM manipulation renders stimulus attributes less accessible for future recall.

The hide-and-seek of retrospective revaluation: recovery from blocking is context dependent in human causal learning.

In a typical blocking procedure, pairings of a compound consisting of 2 stimuli, A and X, with the outcome are preceded by pairings of only A with the outcome (i.e., A+ then AX+). This procedure is known to diminish responding to the target cue (X) relative to a control group that does not receive the preceding training with blocking cue A. We report 2 experiments that investigated the effect of extinguishing a blocking cue on responding to the target cue in a human causal learning paradigm (i.e., A+ and AX+ training followed by A- training). The results indicate that extinguishing a blocking cue increases conditioned responding to the target cue. Moreover, this increase appears to be context dependent, such that increased responding to the target is limited to the context in which extinction of the blocking cue took place. We discuss these findings in the light of associative and propositional learning theories.

Priming associations between bodily sensations and catastrophic misinterpretations: Specific for panic disorder?

Cognitive models assume that panic disorder is characterised by a tendency to misinterpret benign bodily symptoms (e.g. breathlessness) in a catastrophic fashion (e.g. suffocation). This is a central part of the cognitive model which presents a core focus for treatment. Several studies have supported this hypothesis. These studies have, however, almost always relied on self-report. In addition to susceptibility to biases (e.g. distortions of memory), a limitation of research based on verbal report is its inability to capture the spontaneous/automatic nature that is attributed to these catastrophic interpretations. The present paper reports on two experiments in which a priming procedure was used to test the hypothesis that panic disorder is characterised by spontaneous catastrophic interpretations and whether this effect is 'specific' to panic disorder. In line with predictions from the cognitive model, it was observed in the first experiment that the panic group demonstrated facilitated responses to trials consisting of a 'symptom' prime and a 'catastrophic outcome' target (e.g. breathlessness - suffocate). Similar effects were not observed for an anxious control group and a nonclinical control group, supporting the specificity of this effect. Interestingly, however, significant priming effects were observed for a group of mental health professionals (part of the healthy control group) who had no history of panic disorder. Subsequently, this unexpected observation was explicitly addressed in a second experiment, which confirmed the findings of Experiment 1. Together, these results suggest that associations between mental representations of benign bodily symptoms and catastrophic outcomes might develop as part of professional knowledge and experience, and should not necessarily be viewed as pathogenic. Theoretical and clinical implications are discussed.