NASHVILLE, Tenn. (AP) -- Two-time Daytona 500 winner Sterling Marlin has been undergoing deep brain stimulation surgery as part of his treatment for Parkinson's disease.
Marlin's daughter, Sutherlin House, announced Thursday that Marlin completed the third of four surgery stages this week at Vanderbilt University Medical Center. He began the surgery stages March 11.
Marlin was diagnosed with Parkinson's disease in 2012.
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The deep brain simulation surgery treatment involves the delivery of electrical pulses to brain cells in an attempt to reduce the symptoms of Parkinson's.
Recovery from the surgeries is expected to take three months, but can vary depending on the patient.
Marlin, 61, won consecutive Daytona 500 titles in 1994 and 1995.