New Delhi, July 28: New research suggests that a type of meditation from an ancient yoga tradition can reduce intellectual and emotional symptoms that precede Alzheimer's disease and backs earlier findings that yoga may relieve stress and improve the brain's memory functions.

Led by US neuroscientists, the study found that a three-month course of meditation under the Kundalini Yoga tradition worked better than standard strategies prescribed for the mild intellectual and emotional symptoms that precede Alzheimer's and other forms of dementia.

"Yoga provided a broader benefit than memory training because it also helped with mood, anxiety and coping skills," Helen Lavretsky, professor-in-residence at the department of psychiatry at the University of California, Los Angeles, who led the study, said in a media release.

The study is being described as the first to compare outcomes from yoga and meditation with those from memory training, which involves activities such as working on crossword puzzles to using computer programs to enhance memory. The findings were published earlier this year in the Journal of Alzheimer's Disease.

The researchers asked 25 participants to practise a type of yoga called kirtan kriya that involves singing or chanting, stretching the arms and deep inhalation.

After 12 weeks, they observed significantly stronger improvements among those who had practised the yoga than among those who had practised the memory training.

"The form of yoga we prescribed is gentle to the body and appropriate for people in older age groups," Harris Eyre, a physician and research team member from the University of Adelaide, Australia, told The Telegraph over the phone.

"These results add more evidence to support the use of yoga to reduce stress and improve memory."

Several past studies had highlighted the use of various types of yoga meditation and exercises to counter stress and major depression.

Doctors at the Vardhaman Mahavir Medical College, New Delhi, had about a decade ago shown that yoga practice by patients with clinical depression can improve their attention span and speed of movement.

The US-based Alzheimer's Research and Prevention Foundation, which supported the study, recommends a 12-minute exercise of kirtan kriya a day as a way of reducing stress and increasing activities in the brain that are key to memory functions.

The foundation has described kirtan kriya as an exercise that involves repeating a mantra - "Saa, taa, naa, maa" - while sitting with a straight spine, eyes closed.

The practice involves alternating the singing in a normal voice, a whisper, in silence, then back to a whisper and normal voice. The exercise ends with deep inhalation and hands stretched over the head and exhalation as the hands are brought down.

A "white paper" on the foundation's website outlines the research findings from studies that investigated the impact of kirtan kriya on mental functions.

The foundation has cited a 2009 study that showed that kirtan kriya enhances blood flow to the brain's posterior cingulate gyrus, a structure crucial to episodic memory retrieval and among the first areas to show declining functions with the progress of Alzheimer's disease.