A brain emulation may want to modify so that when it multiplies numbers together, instead of its hardware emulating all the neurons involved, it performs the multiplication on a standard computer processor.

This would be far faster, more accurate, and less memory intensive.

Implementation would involve figuring out how the hardware recognizes the intention to perform a multiplication, represent the numbers digitally, and then present the answer back to the emulated neurons. This is outside the scope of any mechanism we might have to make changes within our brains, which would not be able to modify the emulator.