title: Differential Left Hippocampal Activation during Retrieval with Different Types of Reminders: An fMRI Study of the Reconsolidation Process.
abstract: Consolidated memories return to a labile state after the presentation of cues (reminders) associated with acquisition, followed by a period of stabilization (reconsolidation). However not all cues are equally effective in initiating the process, unpredictable cues triggered it, predictable cues do not. We hypothesize that the different effects observed by the different reminder types on memory labilization-reconsolidation depend on a differential neural involvement during reminder presentation. To test it, we developed a declarative task and compared the efficacy of three reminder types in triggering the process in humans (Experiment 1). Finally, we compared the brain activation patterns between the different conditions using functional magnetic resonance imaging (fMRI) (Experiment 2). We confirmed that the unpredictable reminder is the most effective in initiating the labilization-reconsolidation process. Furthermore, only under this condition there was differential left hippocampal activation during its presentation. We suggest that the left hippocampus is detecting the incongruence between actual and past events and allows the memory to be updated.
authors.affiliation: Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Instituto de Fisiología, Biología Molecular y Neurociencias-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Forcato
authors.affiliation: Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Instituto de Fisiología, Biología Molecular y Neurociencias-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Luz
authors.initials: L
authors.lastname: Bavassi
authors.affiliation: Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia, CONICET, Buenos Aires, Argentina.|Centro Universitario de Imágenes Médicas, Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, Buenos Aires, Argentina.
authors.forename: Gabriela
authors.initials: G
authors.lastname: De Pino
authors.affiliation: Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Instituto de Fisiología, Biología Molecular y Neurociencias-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Rodrigo Sebastián
authors.initials: RS
authors.lastname: Fernández
authors.affiliation: Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia, CONICET, Buenos Aires, Argentina.|Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina.
authors.forename: Mirta Fabiana
authors.initials: MF
authors.lastname: Villarreal
authors.affiliation: Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Instituto de Fisiología, Biología Molecular y Neurociencias-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: María Eugenia
authors.initials: ME
authors.lastname: Pedreira
mesh_terms: D000293:Adolescent; D000328:Adult; D001245:Association Learning / Q000502:physiology; D003463:Cues; D005260:Female; D006624:Hippocampus / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D011939:Mental Recall / Q000502:physiology; D033281:Nontherapeutic Human Experimentation; D017010:Reminder Systems; D055815:Young Adult