From a study by Miranda RA and Ullman MT Neuroimage. 2007 Nov 1;38(2):331-45. (Online version not yet available):
Language and music share a number of characteristics. Crucially, both domains depend on both rules and memorized representations. Double dissociations between the neurocognition of rule-governed and memory-based knowledge have been found in language but not music. Here, the neural bases of both of these aspects of music were examined with an event-related potential (ERP) study of note violations in melodies. Rule-only violations consisted of out-of-key deviant notes that violated tonal harmony rules in novel (unfamiliar) melodies. Memory-only violations consisted of in-key deviant notes in familiar well-known melodies; these notes followed musical rules but deviated from the actual melodies. Finally, out-of-key notes in familiar well-known melodies constituted violations of both rules and memory. All three conditions were presented, within-subjects, to healthy young adults, half musicians and half non-musicians. The results revealed a double dissociation, independent of musical training, between rules and memory: both rule violation conditions, but not the memory-only violations, elicited an early, somewhat right-lateralized anterior-central negativity (ERAN), consistent with previous studies of rule violations in music, and analogous to the early left-lateralized anterior negativities elicited by rule violations in language. In contrast, both memory violation conditions, but not the rule-only violation, elicited a posterior negativity that might be characterized as an N400, an ERP component that depends, at least in part, on the processing of representations stored in long-term memory, both in language and in other domains. The results suggest that the neurocognitive rule/memory dissociation extends from language to music, further strengthening the similarities between the two domains. [emphasis added]
This is interesting in numerous ways. First, we see that rule violations and memory violations elicit the same activity, regardless of whether the medium is language or music. Second, this activity occurs regardless of musical training (and I want to emphasize here that all healthy young adults have heard plenty of music, so in a sense this study is flawed, but where are you going to find healthy young adults who have never heard music?).
Third, I begin to wonder if this might not extend not only to aurally-presented activities, but whether the brain processes all memory and rule violations in the same way? Could this explain some other abilities that music training seems to enhance (mathematics, spatial representation)?
In any case, what’s important to take away from this study, is that music and language get processed in the same areas of the brain, and that therefore exercise in one, leads to fitness in the other.