Interesting. Should that ever be possible that would be an
amazing achievement. I tend to think they'll use some standard
psychological memory tests on animals they test with; boring
regular memory tests. If it shows they have significantly better
recall rate, then eventually they'll use that on human and do
the same boring psychological testing procedures.
Symbolic interpretation _might_ follow as an auxiliary line of
research but I don't think it's required for an effective
solution to memory problems or memory enhancement.
Interpretation can be wholly external and ethically, it's likely
that it will be.. for the most part; mostly because
interpretation isn't necessary for effective deployment.