title: Massed and distributed repetition of natural scenes: Brain potentials and oscillatory activity.
abstract: Neural measures of repetition can result in either repetition suppression or enhancement effects, with enhancement sometimes interpreted as indicating episodic retrieval, rather than stimulus habituation. Here, we manipulated whether repetitions were massed (consecutive) or distributed (intermixed) and measured event-related potentials and oscillatory activity, investigating the question of whether there is evidence of "spontaneous" episodic retrieval for distributed, but not massed, repetition. Results showed that distributed repetition uniquely prompted a significant centroparietal old-new effect as well as enhanced theta, compared to either novel presentations or massed repetitions, consistent with a hypothesis of spontaneous retrieval. Massed repetition, on the other hand, prompted repetition suppression and reduction of the N2/P2. Taken together, the data suggest that distributed repetition may facilitate later memory performance because it spontaneously retrieves prior representations.
authors.affiliation: Department of Neuroscience, University of Parma, Parma, Italy.
authors.forename: Vera
authors.initials: V
authors.lastname: Ferrari
authors.affiliation: Center for the Study of Emotion and Attention, University of Florida, Gainesville, Florida, USA.
authors.forename: Margaret M
authors.initials: MM
authors.lastname: Bradley
authors.affiliation: Department of Psychology, University of Bologna, Bologna, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Codispoti
authors.affiliation: Center for the Study of Emotion and Attention, University of Florida, Gainesville, Florida, USA.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Lang
mesh_terms: D001288:Attention / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D058256:Brain Waves; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006185:Habituation, Psychophysiologic / Q000502:physiology*; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D009433:Neural Inhibition; D060865:Repetition Priming; D013826:Theta Rhythm / Q000502:physiology*
keywords: EEG; Emotion; Learning