.... Something to do with the photo for sure, though
I'd guess it has something to do with the photo too, otherwise she wouldn't be subject to having keep looking at it throughout the week.....
IIRC, there was a study done into subliminal messaging in the UK around the mid 1980's, during certain cinema screenings. Shortly before the interval, frames showing popcorn were quickly displayed between the normal film frames and the number of poeple buying popcorn increased, versus those watching films without the inserted frames.
The hit TV series, The Young Ones, even had an experimental go although they made it quite obvious....anyone with a VCR could plainly see the bird-in-flight frames which briefly flicked up on a normal screen... what the intention was, I have no idea, but most of the kids at school were buzzing about it.
There were even suggestions of subliminal back-masking floating around at that time, where popular records (remember them.....vinyl LP's) were played backwards and devil-worship messages were purportedly heard. This claim was mainly aimed at the rock and metal groups, because they didn't fit in with 'normal society' views at the time and their regular lyrics aready pushed boundaries....
How many impressionable kids had the technical capacity and even the
patience to sift though all of their LP's in reverse, at that time?
EDIT: Play some of the recent pop/rock/rap/soul/whatever tracks backwards and I'm sure you'll hear something which sounds strange/offensive....whether it sounds any more offensive than some of the rap stuff played normally, I'll leave up to you to decide...