The number of people agreeing to donate their brains to medical research after death has almost doubled following a campaign, a charity has said.
The Parkinson's Disease Society said an extra 2,332 people had signed up to help scientists study the disease following an appeal in April, bringing the total to 4,032.
Celebrities including Jane Asher, Jeremy Paxman and John Stapleton have already pledged to donate their brain but the charity now wants younger people with Parkinson's to sign up.
''We are delighted with the response to our appeal. Scientific research on brains from people both with and without Parkinson's is essential to help us move closer to our goal.'