We find that the activity of ~30% of posterior insula neurons and up to ~15% of anterior insula neurons is significantly modulated in response to these basic sounds. The latencies of these responses are very similar to primary auditory cortex, though the responses are much more transient. (2/5)

Many of these neurons also showed clear preferred tuning to particular tone frequencies - completely unsurprising for auditory cortex, but an interesting finding for insula. An important aspect is that there was no task required, so there was no behavioral context for these stimuli. (3/5)

Overall, these results are consistent with what others have shown in LFPs, though usually those are examined in behaviorally-relevant contexts. These findings highlight that insula cares about fundamental sound attributes, which is important to know when considering responses to other stimuli. (4/5)