Hubert D. Zimmer

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Recognition memory is usually thought of as comprising two distinct memory processes, namely familiarity and recollection. This distinction is reflected in specific event-related potential (ERP) components associated with both subprocesses. A mid-frontal attenuated negativity for correctly recognized old items relative to new ones around 400 ms has been(More)
It is shown that visuo-spatial working memory is better characterized as processes operating on sensory information (visual appearance) and on spatial location (environmental coordinates) in a distributed network than as unitary slave system. Results from passive (short-term) and active memory tasks (imagery) disclose the properties (capacity, content) and(More)
Episodic memory for intrinsic item and extrinsic context information is postulated to rely on two distinct types of representation: object and episodic tokens. These provide the basis for familiarity and recollection, respectively. Electrophysiological indices of these processes (ERP old-new effects) were used together with behavioral data to test these(More)
Different forms of perceptual memory have opposite physiological effects. Whereas repetition priming often leads to suppression of brain responses, explicit recognition has been found to enhance brain activity. We investigated effects of repetition priming and recognition memory on early gamma-band responses. In a study phase, participants performed a(More)
The assumption was tested that familiarity memory as indexed by a mid-frontal ERP old-new effect is modulated by retrieval orientation. A randomly cued category-based versus exemplar-specific recognition memory test, requiring flexible adjustment of retrieval orientation, was conducted. Results show that the mid-frontal ERP old-new effect is sensitive to(More)
We present a neurocognitive model of long-term object memory. We propose that perceptual priming and episodic recognition are phenomena based on three distinct kinds of representations. We label these representations types and tokens. Types are prototypical representations needed for object identification. The network of non-arbitrary features necessary for(More)
Memory of size and orientation of objects was tested in explicit and implicit memory tests. Explicit memory was tested by object recognition and by recognition of the congruency of the changed sensory features. Implicit memory was tested by size assessment (Exps. 1 and 2), orientation judgement (Exps. 4 and 5), picture-fragment naming (Exp. 6), and(More)
Within dual-process accounts of recognition memory, familiarity (as opposed to recollection) is often referred to as a rather automatic and context-free process. Thus, in episodic object recognition, familiarity and its electrophysiological ERP signature are supposed to index prior occurrence of an object independent of the context the object was originally(More)
In a recognition memory experiment, the claim was tested that intrinsic object features contribute to familiarity, whereas extrinsic context features do not. We used the study-test manipulation of color to investigate the perceptual specificity of ERP old-new effects associated with familiarity and recollection. Color was either an intrinsic surface feature(More)