Which psychologist soon disproved wundt's argument that learning and memory could not be studied experimentally?

I believe the answer is: Ebbinghaus

For his experiment on memory , Ebbinghaus use  simple acoustic encoding and maintenance rehearsal that make a subject try to remember several list of words that have similar syllabels and ending.
As it turned out , language and memory shows strong correlation because people are much more likely to forget or mixed up the meaning of similar sounding words.