Without more information, I can only speculate that your wife may be having visual hallucinations associated with delirium or a sleep disturbance such as sleep walking.
Delirium is a type of cognitive mental disorder - others are dementia and amnesia. It is characterized by a disturbance of consciousness and a change in awareness and understanding (cognition).
Often the cause for delirium is unknown. Delirium can be caused by a general medical condition (e.g., head injury or organic dementia associated with Alzheimer's disease), a substance-induced condition (e.g., medication), or a combination of the two.
Delirium caused by a substance may be due to either intoxication by that chemical or withdrawal from it. Research has shown that some people taking an opioid medication, such as Oxycontin, will develop hallucinations.
This is more likely if your wife's pain, when she awakens at night, causes her to take more of the drug. The fact that your wife sees her "plays" just as she is waking up suggests a sleep-related problem as a contributing factor.
I recommend that she seek professional help. She should make sure she is not taking extra Oxycontin in the middle of the night, and she should ask the doctor about a possible connection with her hallucinations.
The presentation of her problem, especially since there are no other symptoms of mental disturbances or mental incapacity, does not indicate Alzheimer's disease.
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