Context effects on familiarity are familiarity effects of context - an electrophysiological study

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 encountered in, e.g., [Ecker, U.K.H., Zimmer, H.D., Groh-Bordin, C., in press. Color and context: An ERP study on intrinsic and extrinsic feature binding in episodic memory. Mem. Cogn.]). Yet, contextual sensitivity of familiarity has also been reported (e.g., [Tsivilis, D., Otten, L.J., Rugg, M.D., 2001. Context effects on the neural correlates of recognition memory: An electrophysiological study. Neuron 31, 497-505.]). We argue that considering attentional and perceptual factors of target processing is vital in understanding these conflicting results. Presenting target objects on contextual landscape scenes, we introduced a cueing technique designed to focus subjects' attention on target processing. We demonstrate that context effects on familiarity are diminished if the attentional impact of contextual stimuli is experimentally controlled, arguing that contextual influences on object familiarity are indirect and mediated by factors such as salience and attentional capture. Results suggest that salient context stimuli may elicit an independent familiarity signal instead of directly impacting on the familiarity signal of the target object. We conclude that (a) object familiarity is in principle a rather automatic and context-free process, and that (b) the study of episodic memory can profit substantially from adopting a dynamic processing perspective.