He is diagnosed with Asperger's Syndrome in the second episode of the first season, (Man Versus Possum). Max is unaware of his Asperger's diagnosis in the early episodes, but during the second season, he learns about it after witnessing a fight between Adam and Crosby. Because of his Asperger's, it is difficult for him to naturally communicate with others, and he often only thinks of himself. This causes a rift in his relationship with Haddie, who gets jealous of all the attention he receives.
In the Season 2 finale, while at the hospital, Max becomes very angry, saying that he wants pancakes more than he cares about Amber Holt, even going as far as saying that doesn't care about her. Adam scolds Max for his hurtful comments, but Max believes he didn't do anything wrong, even though at the end he apologizes to Sarah Braverman for what he said.
Kristina and Adam parents decide to transfer Max to a mainstream school after being told that he is very intelligent. They do this in order to challenge him academically even though they are worried about his social life. He is trying hard to make friends, though it proves difficult. It is also discovered that Max is academically enriched. Even though Max is socially behind others his age, he is academically far above most others his age and older.
In Season 3, Max makes a friend with a boy named Micah, who has spina bifida. This is one of Max's only friends of the series, and the two have many sleepovers together.
In Season 4, Max is elected the class president of Cedar Knoll Middle School with some help from Haddie. With much work, he and Kristina are able to bring back the school vending machines, which were taken away when Max arrived at the middle school.
In Season 5, Max becomes interested in photography while building a friendship with fellow photographer and his Aunt Sarah's ex-boyfriend, Hank Rizzoli. Together, they work on taking photos, and while they spend time with each other, Hank realizes that he has Asperger's like Max. Max and Micah later stop being friends once Max tells Micah that his wheelchair will always prevent him from playing basketball correctly. Max tries to apologize, but Micah realizes he is embarrassed of Max's attitude.
Max starts to like a girl named Dylan in the charter school his mom created. At first Max comes to be a stalker from Adam's advice but when Kristina and Adam talk more about it to him he starts to understand a little more. Dylan starts to come over to Max's house and Max considers it a "date" but she likes to hang out with Kristina and Nora. Max then tries to ask her out but when he comes over he sees her kissing another boy. This creates major issues including Max touching her. He finally comes to terms with the fact she does not like him. In the final episode he photographs Sarah and Hank's wedding. He is also seen dancing with a girl.