MARTINEZ - Susan Polk's oldest son, who has testified against her in her murder trial, initially believed that she attacked her husband in self-defense, the defendant testified today on her third day on the stand. Polk, 48, sought to portray a different perspective of Adam Polk from what he told the jury himself. Adam Polk, a UCLA student studying philosophy and English, testified that his mother was "cuckoo for Cocoa Puffs" and "a sick, sick person who's in dire need of being in a very controlled environment for a very long time." Susan Polk, who is defending herself against charges...