If you can recite lenghty passages of someone elses work verbatim then you have probably got a photographic memory. This means you will know you are copying from another source.
The information that you PhotoRead is processed by your preconscious processor. Much of the imformation is split into compartments of appropriate subjects. You will have taken on the ideas of the author but in a moment of spontaneous activation you would find that it comes out in your own words with your own understanding of it.
If the stuff that you PhotoRead is for essays and papers then you will do a degree of manual activation anyway. It gives you the opportunity to credit the author.
If we all want to get nitty gritty about it then we could say we have plagiarised the Phrase "Just do it." However It was a phrase everyone heard one of their guardians say at some time or another as we were growing up.
So the length of the material also needs to be substantial in order to consider it plagiarised. I am sure that you would recognise when it isn't your writing.
Alex