Complex sentence: Langleben was inspired to test lie detection while he was at Stanford University studying the effects of a drug on children with Attention Deficit Disorder (ADD), who have a more difficult time inhibiting the truth.
Split into simpler sentences: Langleben was inspired to test lie detection while he was at Stanford University studying the effects of a drug on children with Attention Deficit Disorder (ADD). He found that these children have a more difficult time inhibiting the truth.