Some hailed the treatment "a miracle cure"
Thirteen UK centres offering controversial treatment for people with dyslexia have been shut down due to financial difficulties.
The Dore programme claimed exercises such as tying knots and balancing on "wobble boards" stimulated parts of the brain and improved reading and writing.
Some 30,000 children and adults have enrolled on the programme since 2000.
The company website said administrators were in talks with possible buyers who would continue treating customers.
The centres were created by millionaire businessman Wynford Dore, whose daughter Susie suffered from such acute dyslexia that she attempted suicide three times.
He has previously said the problem has been very misunderstood and the science has never been there to provide an understanding of the root causes and hence provide a solution.
Balancing on a "wobble board"
Throwing and catching bean bags
Tying knots in pieces of string
Some have hailed the £1,500 12-month programmes as a "miracle cure" while others claim it is nothing more than a money-making exercise.
The treatment aims to stimulate a part of the brain called the cerebellum through regular exercises.
The cerebellum is a tangerine-sized part of the brain which co-ordinates movement and balance.
The programme had been endorsed by rugby player and Strictly Come Dancing contestant Kenny Logan and former Wales rugby captain Scott Quinnell.
Alternative therapy warning
On Thursday, a recorded message on the company's telephone line said: "We have temporarily suspended operations. Please be assured we are working on a resolution."
Its website said administrators took over the company on Wednesday and were in talks with possible buyers.
BRITISH DYSLEXIA ASSOCIATION
It said this was with the aim of securing a sale which provides "continuity of treatment for customers".
Judi Stewart, chief executive of the British Dyslexia Association, urged caution over such alternative therapies, saying there was no cure for dyslexia.
"The BDA recommends specialist teaching, which is multi-sensory stimulated, as these address all of the effects of dyslexia in learning."
The charity advised any customers with concerns to call its helpline.
Dore centres are located in Bromley, Wembley, Bedford, Belfast, Cardiff and Edinburgh, with the head office in Kenilworth.
Further centres are in London, Manchester, Sheffield, Somerset and Southampton.
Overseas, there are centres in the US and Australia.