Austin State Hospital, formerly known as the State Lunatic Asylum, is the oldest psychiatric hospital in the state of Texas. Established by the Legislature in 1856, it commenced operations in 1861 with twelve patients. The name was changed in 1925.
The Hospital is the subject of a history by Sarah C. Sitton, Life at the Texas State Lunatic Asylum 1857 - 1997, published by the Texas A&M University Press in 1999 as Number 82 in the Centennial Series. )Source
http://en.wikipedia.org/wiki/Austin_State_Hospital)
You can also go to this link for more information
http://www.dshs.state.tx.us/mhhospitals/AustinSH/Obtaining mental health records for ancestors can be very difficult but you should be able to contact the hospital to find out what their policy is.