Sleep Leads to Changes in the Emotional Memory Trace: Evidence from fMRI

摘要

After information is encoded into memory, it undergoesnan off-line period of consolidation that may occur optimally duringnsleep. The consolidation process not only solidifies memoriesnbut also changes them in useful and adaptive ways.nHere, we provide evidence for a shift in the neural structuresnused to retrieve emotional memories after a night of sleep comparednto a day of wakefulness. Although the hippocampus wasnactivated during successful retrieval of negative objects regardlessnof whether participants slept during a delay, sleep led to anshift from engagement of a diffuse memory retrieval network—nincluding widespread activity in the lateral prefrontal and parietalncortices—to a more refined network of regions—includingnthe amygdala and ventromedial pFC. Effective connectivitynanalyses revealed stronger connections among limbic regionsnafter sleep versus wake. Although circadian effects may havencontributed to these findings, our data strongly suggest that annight of sleep is sufficient to evoke qualitative changes in thenemotional memory retrieval network. ■