Ragdoll cat intelligence...

Is this normal for a ragdoll? A few years ago I got a beautiful Balinese seal point ragdoll cat that was abandoned by their owner. As far as I can tell she is perfectly healthy. Her appetite is good. She is athletic. She meows occasionally and very quietly. However she seems kind of dumb. I have another cat that I would describe as normally intelligent... In fact smart. The rag doll appears to have no self-defense mechanism. She doesn't react much to noise. And she has the unusual habit of finding a new place and staying there for months at a time (counting her daily activities and the time I spend with her.) She will often times sit in a corner facing the corner rather than looking around her environment for protection. And she absolutely displays the standard ragdoll characteristic of folding up into a rag doll once she is picked up. She also appears slightly neurotic about cleaning herself by over grooming so I take great efforts to avoid damage to her fur. Is this behavior the result of selective over breeding? She wouldn't survive 5 minutes out in the real world.