LOS ANGELES, Feb 17 ― The family of Beach Boys founder Brian Wilson have asked a court to put him under a conservatorship as he struggles with a neurocognitive issue and requires help with daily life following his wife's recent death, they said.

Wilson, regarded by many as a singular musical genius, has “a major neurocognitive disorder,” according to court documents filed in Los Angeles this week, media reported.

He “is unable to properly provide for his own personal needs for physical health.”

Following the death of Wilson's wife Melinda in late January, his family has asked the court for his business manager LeeAnn Hard, as well as his publicist and manager Jean Sievers, to be appointed to manage his affairs, a statement on the musician's website said.

“This decision was made to ensure that there will be no extreme changes to the household and Brian and the children living at home will be taken care of and remain in the home where they are cared for,” the family's statement said.

“Brian will be able to enjoy all of his family and friends and continue to work on current projects as well as participate in any activities he chooses.”

Sievers told The New York Times that Wilson, 81, had been “diagnosed with dementia.”

Wilson's wife Melinda died at their Beverly Hills home on January 30 at the age of 77, he said on social media.

“Melinda was more than my wife. She was my saviour. She gave me the emotional security I needed to have a career. She encouraged me to make the music that was closest to my heart. She was my anchor,” he wrote at the time.

A towering figure in the world of music, Wilson is responsible almost single-handedly for the California sound pioneered by the Beach Boys in the 1960s.

His signature blend of easy-sounding pop, underlaid by complex harmonies and often deeply poetic lyrics, elevated the band far beyond its disposable surf-song image.

The five-piece lineup melded innovative vocalising with the driving rhythms of rock and roll, and used unconventional recording techniques to create an instantly recognisable sound.

Wilson's ferocious talent was, at times, overshadowed by mental health challenges that have dogged him throughout his adult life.

In 1964, he suffered a breakdown while on tour, forcing him to focus on recording, but heralding a period of extreme creativity that produced “Pet Sounds,” amongst other albums.

Experiments with drugs were coupled with bouts of depression and auditory hallucinations, as well as a diagnosis of schizoaffective disorder and bipolar disorder, according to a biographer. ― AFP