[2][6] While serving in the army, Carroll's mother was diagnosed as suffering from Huntington's disease (HD), a fatal, incurable, genetically inherited neurodegenerative illness.

[2][6] Learning that he and his siblings were each at 50% risk of having inherited the genetic abnormality that causes HD, and having no scientific background, Carroll enrolled in an Army-sponsored basic biology course, initiating a career as a neuroscientist.

"[16] Alongside clinical researcher Dr Ed Wild and Emmy award-winning journalist and HD patient advocate Charles Sabine, Carroll has delivered plain-language digests of research news for patients and family members at major scientific conferences, including the 2009[19] and 2011[20] World Congresses on Huntington's Disease in Vancouver and Prague, and the 2010 European Huntington's Disease Network Annual Congress.

[21] In 2010, Carroll's life, work and family were the subject of an episode of the CBC News Network documentary Connect with Mark Kelley, entitled "Fighting Huntington's disease".

[32] Along with HDBuzz co-founder Dr Ed Wild, Carroll received the 2012 Michael Wright Community Development Award from the Huntington Society of Canada.