One elderly man whose wife had died of Alzheimer's disease two years before he contracted terminal cancer was delighted when he "visited" with her in her pre-Alzheimer state. He exclaimed that he had "got my wife back!" They had been wonderful companions to each other for some fifty, years before the Alzheimer's disease took her away from him long before her death. He had cared for her himself for the last several years of her life, and it was very painful for him to see the person that he knew slip away while her body remained.
After the "visitation" experience, he believed that he would be reunited with his beloved wife in her pre-Alzheimer condition. That belief allowed him to approach the last few days of his life with equanimity, and even a measure of joy.