Seth Rogen
House of Cards fan Seth Rogen makes his appearance at the Senate to discuss Alzeimer's disease and not marjuana Youtube

Seth Rogen has joked with US senators that he would not testify to help legalise marijuana while appearing at an emotional meeting to discuss Alzheimer's.

The comedian, whose film credits include Knocked Up, Superbad and This is the End, was addressing US politicians about the impact the disease had on his mother-in-law and asked Washington to continue funding research.

Rogen's impassioned speech was also smattered with his trademark wit, including referring to himself as a "lazy, self-involved, generally self-medicated, man child".

During his opening statment Rogen said: "Thank you for the opportunity to testify today and for the opportunity to be called an expert at something, because that's cool. You told me you never saw Knocked Up, chairman, so that's a little insulting.

"I am aware that this has nothing to do with the legalisation of marijuana, in fact if you can believe it, this concerns something that I find even more imporant."

Senator Tom Harkin took the opportunity to himself joke: "I would like it put on record that I wager this is the first time in any congressional meeting in history that the words 'knocked up' have been used."

The 31-year-old actor detailed how he used to think Alzeimer's was somethiung that only "really, really old people" got and how his own experience changed that view.

He told senators that his charity Hilarity for Charity had managed to get 18 high schools involved with raising money towards research into the disease, an acheivement he was proud of "considering Xbox One and PS4 came out this year."