(Washington Times) Adam Lanza, the Newtown, Conn., teenager who shot and killed 20 Sandy Hook Elementary School students and six staffers — and then himself — in December, was diagnosed with a medical condition at age 6 that made it unbearable for him to be touched.

With a sensory integration disorder, according to a PBS investigation that aired Tuesday evening and was subsequently reported by ABC, Lanza couldn’t deal with being touch or with chaotic situations, including loud, bustling school hallways and classrooms. As the years progressed, he became increasingly isolated, ABC reported.

Those with the condition are sometimes even put off by the clothing they wear, ABC said.

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