Board Thread:General Discussion/@comment-1023843-20171030064529/@comment-33279747-20171101032732

She may have some symptoms consistent with high-functioning Autism but there are two obstacles to this theory (along with all the other "X character has X condition" theories):

1. I doubt the LH writers wrote her character with any specific neurological/developmental disorder in mind - it's merely a coincidence.

2. She's too young. We would have to wait until Lisa's pre-teen years to really know this for sure, to see if more symptoms develop or the current ones do not change. And we'll never know that since cartoon characters have a habit of never aging.