The effect of stress on memory varies according to its intensity. Small amounts of stress often have a positive effect on alertness and facilitate memory, while intense stress can overstimulate the individual, cause high anxiety, and hinder memory functioning. The inability to remember events from early in life is apparently universal. Assessing the effects of stress or trauma on children's memory is difficult. Research studies of adult victims of child sexual abuse indicate that repressed memories of sexual abuse are probable and that the extent of memory repression depends on several distinct variables. Many therapists believe that repressed memories are authentic, but they also recognize that inaccurate memories can occur. Suggestion appears to be a leading cause of inaccurate memory. The need for more research to resolve the controversy about repressed memories is emphasized.