Recently, there has been some evidence for the functional importance of gamma oscillations in the amygdala as well. A 40 Hz gamma oscillation couples the activity of the amygdala, rhinal cortices, and striatum during an appetitive learning task (Bauer et al., 2007; Popescu et al., 2009). Moreover, fear-related gamma oscillations in the BLA have been recently demonstrated (Courtin et al., 2013). Thus, as in HPC, gamma frequency oscillations may be essential for information transfer to and from amygdala nuclei. Given the role of theta frequency oscillations in generating and maintaining fear states, and the strong relationship between theta and gamma in HPC (Belluscio et al., 2012), we hypothesized that BLA theta oscillations may coordinate gamma frequency activity in a behaviorally-relevant manner, and, as in the dorsal CA1, gamma oscillations could provide windows for coupling BLA activity to hippocampal and prefrontal inputs.
