Assessment of freezing behavior and neurophysiological data acquisition were performed as previously described (Likhtik et al., 2014) and took place on the fourth day. Each animal received five CS+ and CS− presentations without shocks in a novel context. The discrimination score was calculated for each animal, and was the difference between percent time spent freezing in CS+ and CS−. Multi- and single-units were bandpass-filtered (600-6000 Hz) and recorded at 32 kHz. LFP signals from all areas were bandpass filtered (1-1000 Hz), acquired at 1894 Hz, and referenced against the frontal screw; some recordings were simultaneously referenced to the cerebellar screw.
