Creating a False Memory in the Hippocampus

• Published in: Science (American Association for the Advancement of Science) Vol. 341; no. 6144; pp. 387 - 391
• Main Authors: Ramirez, Steve, Liu, Xu, Lin, Pei-Ann, Suh, Junghyup, Pignatelli, Michele, Redondo, Roger L., Ryan, Tomás J., Tonegawa, Susumu
• Format: Journal Article
• Language: English
• Published: Washington, DC American Association for the Advancement of Science 26.07.2013; The American Association for the Advancement of Science
• Subjects: Activation; Amygdala; Amygdala - physiology; Anatomical correlates of behavior; Animals; Association; Associative memory; Behavioral neuroscience; Behavioral psychophysiology; Biological and medical sciences; Brain; CA1 Region, Hippocampal - cytology; CA1 Region, Hippocampal - physiology; Channelrhodopsins; Conditioning; Conditioning (Psychology); Control groups; Dentate Gyrus - cytology; Dentate Gyrus - physiology; Dependovirus - genetics; Doxycycline - administration & dosage; Experimental Groups; False memory; Fear; Formations; Freezing; Fundamental and applied biological sciences. Psychology; Genes, fos; Hippocampus; Human; Light; Memory; Memory - physiology; Mental Recall - physiology; Mental stimulation; Mice; Mice, Inbred C57BL; Mice, Transgenic; Neurons; Neurons - physiology; Neurosciences; Optogenetics; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Recall; Stimuli; Vertebrates: nervous system and sense organs; Shock; Context; Affect affectivity; Memory; Rodentia; Central nervous system; Emotion emotionality; False memory; Encephalon; Foot; Fear; Vertebrata; Dentate gyrus; Mammalia; Neuron; Mouse; Animal; Recall; Conditioning; Hippocampus
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1239073

Memories can be unreliable. We created a false memory in mice by optogenetically manipulating memory engram—bearing cells in the hippocampus. Dentate gyrus (DG) or CA1 neurons activated by exposure to a particular context were labeled with channelrhodopsin-2. These neurons were later optically reactivated during fear conditioning in a different context. The DG experimental group showed increased freezing in the original context, in which a foot shock was never delivered. The recall of this false memory was context-specific, activated similar downstream regions engaged during natural fear memory recall, and was also capable of driving an active fear response. Our data demonstrate that it is possible to generate an internally represented and behaviorally expressed fear memory via artificial means.