Sandy and Joan Weill. (Ron Adar/Getty Images)

Financier Sanford I. “Sandy” Weill and his wife, Joan, on Tuesday announced a $185 million gift for brain research that they hope will radically change the way we approach such issues as mental illnesses, migraines and sleep disorders by bringing them under the umbrella of neurosciences.

The gift — one of the largest in history in this field — will go to the University of California at San Francisco for the creation of the Weill Institute for Neurosciences and will consolidate various departments within the university and add 45 new basic research labs addressing a wide variety of brain-related conditions.

In an interview, the Weills described their donation as deeply personal. Sandy Weill’s mother suffered from Alzheimer’s for the last decade of her life, and his father had severe depression. One of his best friends committed suicide. Joan Weill’s mother, in contrast, lived until 100½ and died with a sharp mind. Trying to understand why some people’s brains are more resilient to aging or the daily stresses of modern life is one of the fundamental questions they hope can be answered by researchers.

“There have been a lot of discoveries in cancer and cardiovascular disease that have allowed people’s bodies to live longer, but there has not been nearly as much in the neurosciences,” said Sandy Weill, the former Citigroup chief executive officer who built the company into one of the world’s largest financial services companies. Weill, who is 83, added jokingly, “My wife comes from a family with very good brains. Therefore I need this developmental work so I can keep up with her.”

Among the focus areas for the new institute will be Alzheimer’s and other dementias; Parkinson’s disease; sleep disorders; chronic pain and migraine; and paralysis caused by stroke or injury. It will also include basic researchers studying psychiatric disorders, which Joan Weill said is critical to the disruptive mission of the new institute.

“It will remove the stigma of mental illness and bring it into a disease of the brain,” she said. “I think it will make a difference in the lives of so many people.”

Steve Hauser, the institute’s inaugural director, who is known for leading the development of a treatment for multiple sclerosis, said that as people are living longer, the prevalence of neurological disease is becoming a global problem. He thinks the key to finding treatments may lie in understanding the relationships between different states of the brain.

“For example, we now understand sleep disorders are important for not just psychiatric problems but also neurodegenerative problems,” he said.

The past few years have seen rapid investment in the neurosciences. President Obama in 2013 announced the national BRAIN Initiative (Brain Research through Advancing Innovative Neurotechnologies), a public-private collaboration to understand the human brain. Philanthropist Paul Allen, the Microsoft co-founder, stepped up his commitment to neurosciences by bringing his total contribution to the Allen Institute for Brain Science in Seattle to $500 million. Including the Weills’ new gift, the UCSF neuroscience programs alone have received more than half a billion dollars from philanthropists in the past year.

Stanley B. Prusiner, winner of the 1997 Nobel Prize in medicine for his discovery of prions, a class of pathogens that cause neurodegenerative disease, said one of the things that most excites him is that the donation will accelerate the search for drugs that could “actually slow down or stop Alzheimer’s disease and the same thing for Parkinson’s.”

“We’ve made a lot of progress in this area and are very excited about making much more progress,” said Prusiner, a UCSF neurology professor.

In 2010, the Weills were among the first to sign on to the “Giving Pledge” started by Bill and Melinda Gates and Warren Buffett, which challenged the world’s billionaires to give away the majority of their wealth. Their donation to UCSF follows on the heels of two other large philanthropic gifts to medical science in the past month: $250 million donated by Napster co-founder Sean Parker to create a cancer immunotherapy institute and $125 million from businessman and former New York mayor Michael Bloomberg, Jones Apparel Group founder Sidney Kimmel and other philanthropists for cancer immunotherapy research at Johns Hopkins University.

The Weills, who have given away more than $1 billion, are also known for endowing the medical school at Sandy Weill’s alma mater, Cornell University, and for their support of other educational and cultural institutions.

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