Psychologist Eliot Atkins told the court that he conducted a six hour interview of Sandusky, and reviewed materials including the "creepy love letters" Sandusky sent some of his alleged victims and Sandusky's memoir, "Touched."
Based on the interviews and materials, Atkins testified that he diagnosed Sandusky with histrionic personality disorder, which, according to the National Institutes of Health, is a "condition in which people act in a very emotional and dramatic way that draws attention to themselves."
The defense showed excerpts from some of these letter, including one which read, in part: "I write because of the churning in my stomach when you don't care. I still hope there will be meaning to the time we have known each other."
Atkins then testified that, "The letters express his hurt, disappointment and criticism of these people for not getting back what he hoped to get from these relationships."
In addition, the defense called the mother of the young man known as "Victim 1" and questioned her about whether she had ever made remarks about how the allegations her son had levied against Sandusky would lead to a financial windfall. She denied making such statements.
Last week, Victim 1, now 18-years-old, testified that Sandusky fondled and performed oral sex on him in the basement of the Sandusky home.
The defense then called Josh Favel, the woman's former neighbor, who said the woman once spoke with him about Sandusky.
"She asked, "How do I find out if someone is a registered sex offender?" I said "Why" [she said] "I just heard that [Victim 1] was touched by Jerry Sandusky and I want to find out how to take this further."
Sandusky's attorney, Joe Amendola then asked Favel: "What did she say next?"
Favel answered: "I'll own his house."
Favel also testified that he once spoke to Victim 1 about Sandusky: "He said...that when all this was over I will have a nice, new Jeep."
On cross-examination, Favel admitted that he thought Victim 1's mother was a bad person and that he didn't like her.
Additional reporting by CBS News' Paula Reid in Bellefonte, Pa.
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