Brain-wide maps ofFosexpression during fear learning and recall.
Fosinduction during learning labels neuronal ensembles in the hippocampus that encode a specific physical environment, revealing a memory trace. In the cortex and other regions, the extent to whichFosinduction during learning reveals specific sensory representations is unknown. Here we generate high-quality brain-wide maps ofFosmRNA expression during auditory fear conditioning and recall in the setting of the home cage. These maps reveal a brain-wide pattern ofFosinduction that is remarkably similar among fear conditioning, shock-only, tone-only, and fear recall conditions, casting doubt on the idea thatFosreveals auditory-specific sensory representations. Indeed, novel auditory tones lead to as much gene induction in visual as in auditory cortex, while familiar (nonconditioned) tones do not appreciably induceFosanywhere in the brain.Fosexpression levels do not correlate with physical activity, suggesting that they are not determined by behavioral activity-driven alterations in sensory experience. In the thalamus,Fosis induced more prominently in limbic than in sensory relay nuclei, suggesting thatFosmay be most sensitive to emotional state. Thus, our data suggest thatFosexpression during simple associative learning labels ensembles activated generally by arousal rather than specifically by a particular sensory cue.
Genetics Department, Harvard Medical School, Boston, Massachusetts 02115, USA.
Jin-Hyung
JH
Cho
Genetics Department, Harvard Medical School, Boston, Massachusetts 02115, USA.
Sam D
SD
Rendall
Genetics Department, Harvard Medical School, Boston, Massachusetts 02115, USA.
Jesse M
JM
Gray
D000161:Acoustic Stimulation; D000818:Animals; D001245:Association Learning / Q000502:physiology*; D001921:Brain / Q000166:cytology / Q000378:metabolism*; D001931:Brain Mapping; D003213:Conditioning, Psychological / Q000502:physiology; D003463:Cues; D005239:Fear; D006801:Humans; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009474:Neurons / Q000378:metabolism; D016761:Oncogene Proteins v-fos / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism
D016761:Oncogene Proteins v-fos; D012333:RNA, Messenger