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Almut Hupbach

Publications and source records attributed to Almut Hupbach.

4 recordsLinked to original sources

Reconsolidation of episodic memories: a subtle reminder triggers integration of new information.

Recent demonstrations of "reconsolidation" suggest that memories can be modified when they are reactivated. Reconsolidation has been observed in human procedural memory and in implicit memory in infants. This study asks whether episodic memory undergoes reconsolidation. College students learned a list of objects on Day 1. On Day 2, they received a reminder or not, and then learned a second list. Memory for List 1 was tested immediately on Day 2 (Experiment 2) or on Day 3 (Experiment 1). Although the reminder did not moderate the number of items recalled from List 1 on either day, subjects who received a reminder incorrectly intermixed items from the second list when recalling List 1 on Day 3. Experiment 2 showed that this effect does not occur immediately and thus is time-dependent. The reminder did not affect memory for List 2 on Day 3 (Experiment 3), demonstrating that modification occurred only for the original memory (List 1). The study demonstrates the crucial role of reminders for the modification of episodic memory, that reconsolidation of episodic memory is time-dependent, and, in contrast to previous reconsolidation findings, that reconsolidation is also a constructive process, one that supports the incorporation of new information in memory.

Adult↗

The mere exposure effect is sensitive to color information: evidence for color effects in a perceptual implicit memory test.

Priming effects in perceptual tests of implicit memory are assumed to be perceptually specific. Surprisingly, changing object colors from study to test did not diminish priming in most previous studies. However, these studies used implicit tests that are based on object identification, which mainly depends on the analysis of the object shape and therefore operates color-independently. The present study shows that color effects can be found in perceptual implicit tests when the test task requires the processing of color information. In Experiment 1, reliable color priming was found in a mere exposure design (preference test). In Experiment 2, the preference test was contrasted with a conceptually driven color-choice test. Altering the shape of object from study to test resulted in significant priming in the color-choice test but eliminated priming in the preference test. Preference judgments thus largely depend on perceptual processes. In Experiment 3, the preference and the color-choice test were studied under explicit test instructions. Differences in reaction times between the implicit and the explicit test suggest that the implicit test results were not an artifact of explicit retrieval attempts. In contrast with previous assumptions, it is therefore concluded that color is part of the representation that mediates perceptual priming.

Adult↗

A case of psychogenic fugue: I understand, aber ich verstehe nichts.

Psychogenic fugue is a disorder of memory that occurs following emotional or psychological trauma and results in a loss of one's personal past including personal identity. This paper reports a case of psychogenic fugue in which the individual lost access not only to his autobiographical memories but also to his native German language. A series of experiments compared his performance on a variety of memory and language tests to several groups of control participants including German-English bilinguals who performed the tasks normally or simulated amnesia for the German language. Neuropsychological, behavioral, electrophysiological and functional neuroimaging tests converged on the conclusion that this individual suffered an episode of psychogenic fugue, during which he lost explicit knowledge of his personal past and his native language. At the same time, he appeared to retain implicit knowledge of autobiographical facts and of the semantic or associative structure of the German language. The patient's poor performance on tests of executive control and reduced activation of frontal compared to parietal brain regions during lexical decision were suggestive of reduced frontal function, consistent with models of psychogenic fugue proposed by Kopelman and Markovitsch.

Adult↗

Age-related improvements in a conceptual implicit memory test.

The present study investigated developmental improvements in category exemplar generation priming in children from kindergarten to older elementary school age. The strength of categorical links for atypical exemplars increases in this age range, whereas category knowledge for typical exemplars remains relatively stable. Therefore, in comparison with older children, younger children should show less categorical-relational encoding and, thus, less priming for atypical items but not for typical items. This expectation was confirmed in Experiment 1. In Experiment 2, picture versus word format at study dissociated implicit and explicit performance, indicating that the age-related increase in priming for atypical exemplars in Experiment 1 was not an artifact of explicit contamination. The findings suggest that developmental improvements in conceptual priming can be observed when the conceptual knowledge relevant for a given task improves over the age range tested.

Age Factors↗