Research at the Western Australian Centre for Health and Ageing has discerned that a hormone controlling the release of testosterone might be the cause of poor memory in older men.

A study published in this month's issue of the Journal of Alzheimer's Disease revealed that men with increased levels of luteinizing hormone (LH) suffered from a bad memory, than those with lower levels.

The luteinizing hormone produced by the pituitary gland is responsible for the release of hormones including estrogen in women and testosterone in men.

Lead author Zoë Hyde remarked that while previous studies had found high LH levels in men with Alzheimer's disease, this was the first time that an effect had been seen in healthy men.

"This study provides new insight into how hormones affect the brain and reveals a potential target for Alzheimer's disease drug therapies. However, more work is required before we can fully understand the role that LH plays in the brain", she concluded.

The study sponsored by the National Health and Medical Research Council of Australia was the largest in Australia.