Intense musical training at an early age means some kids can acquire perfect pitch—the ability to name or sing a musical note without a reference note—most people miss the window of time during which their brain is the most plastic. As a result, only one in approximately 10,000 adults has perfect pitch (which really may not be so “perfect” after all).

The intricacies of how HDAC inhibitors affect gene expression and how those changes reduce seizures and mania are still up in the air. But while some scientists have been working those details out, others have been noticing that HDAC inhibitors help old mice learn new tricks. These drugs allow adult mice to adapt to visual and auditory changes in ways that are only otherwise possible for juvenile mice. In other words, HDAC inhibitors allowed mice to learn things beyond the typical window, or critical period, in which the brain is capable of that specific type of learning.

Participants in the study were given valproate during one half of the experiment and a placebo during the other half. During the first half, they were trained to associate six different pitches with six proper names (Eric, Rachel, Francine, etc.); in the second half, the same subjects were trained again, but on a new set of pitches and names.The results indicate that even though their training was limited, participants on valproate during the first half of the study came much closer to demonstrating perfect pitch than participants on the placebo.

However, in the second half, participants who’d been on valproate did worse without it, while those who’d taken the drug second didn’t do that much better. The researchers suspect that “a memory conflict” between the pitches and names used in each treatment group might have caused problems. This is, as Schwarzlose notes, an example of proactive interference .

Scientists hope to figure out what kind of learning is going on here and whether not the drug’s capabilities could help people boost brainpower in other areas, like math or foreign languages. While it’s unlikely to be used as a universal tool for enhanced learning—after all, it can cause birth defects—it could help researchers identify more pathways involved in learning.