Prefrontal Cortex Long-Term Potentiation, But Not Long-Term Depression, Is Associated with the Maintenance of Extinction of Learned Fear in Mice

• DOI: 10.1523/jneurosci.22-02-00577.2002
• Publication Date: 2018-04-05T22:36:24Z
• Authors: Cyril Herry; René Garcia
• Keywords: Extinction (optical mineralogy); Stimulus (psychology)

Considerable efforts have been made to identify changes of brain synaptic plasticity associated with fear conditioning. However, for both clinical applications and our fundamental understanding memory processes, it appears also necessary investigate related extinction. We previously showed that extinction freezing a tone conditioned stimulus (CS; paired footshock) in mice results sequence depression potentiation efficacy the medial prefrontal cortex (mPFC). These data as well those from lesion studies suggest direction may modulate learned fear. To test this, we analyzed effects low-frequency stimulation (LFS) high-frequency (HFS) mediodorsal thalamic nucleus, known induce long-term (LTD) (LTP), respectively, on found maintenance phase, using LFS, was resistance Thalamic HFS applied before testing had no effect rate 1 week follow-up tests revealed intact these (with LTP) control displaying LTP-like changes, whereas did not exhibit such displayed return CS. The after lack depression-LTP-like conversion mPFC profoundly alter process consolidation.