Stigler's law of eponymy states, "No scientific discovery is named after its original discoverer." A famous example of this law is the Gaussian distribution, which was introduced by Abraham de Moivre in 1733 and only later was used and defended by Carl Friedrich Gauss.
The neuroscience of language has a few examples of Stigler's law.
Broca's aphasia. Non-fluent forms of aphasia were well known long before Broca.
Broca's area. It is now known that Marc Dax discovered the link between non-fluent aphasia and the left inferior frontal gyrus. Of course, Dax never published his findings so in one sense Broca's claim to fame is justified. Nonetheless, Stigler's law still holds.
Wernicke's aphasia. A fluent form of aphasia, them often referred to as speech amnesia, was also well known before Wernicke.
Wernicke's area. Wernicke was not the first to associate "Wernicke's" aphasia with the left posterior superior temporal gyrus, the region we today call Wernicke's area. That honor appears to belong to Wernicke's mentor Theodor Meynert.
Hebbian learning. This attribution, while not obviously relevant to the neuroscience of language, is a dash of karma for Wernicke. Donald Hebb was not the first to describe "Hebbian learning" as Wernicke discussed the same principle decades earlier.
Junior scientists tend to worry a lot about getting scooped. I've received more than one panicked email from a grad student who discovers a published study almost identical to the one they were just writing up. But if Stigler is correct, precedence doesn't mean all that much in scientific attribution. You don't have to discover it, you just have to popularize it.