I think I know why I obtained the effects in my previous set of experiments that I obtained, where the effect of pre-exposure to a CS was even more pronounced when the context was changed between phases.
I have, at least, made the effect go away where there is no detectable effect of a context change on the pre-exposed groups.
I may even have a small loss of latent inhibition with a context change, but if so it is a small effect and cannot be detected statistically with Ns of 20.
I am optimistic about my potential explanation- I could have uncovered a new effect that, up until this point in time, could have remained unknown due to methodological limitations.
Another experiment is ready to go and hopefully will be underway soon. With luck, it will be finished in the next few weeks.
Right or wrong on my idea, I’ll be posting more detail and data when have more than cross-experiment comparisons with which to work.