Multiple therapies curb declining ability to learn with age

Combination of behavioral enrichment and antioxidant supplementation in diet reveal clear-cut benefits

A new study of beagles led by researchers at the University of Toronto at Scarborough underscores the importance of using a combination of diet and behaviour therapies to curb the progressive decline in the ability to learn that occurs with advanced aging. “We were really surprised just how clear-cut the benefit is of using a combined therapy,” says lead investigator and psychology professor Bill Milgram of the U of T at Scarborough, who specializes in aging research.

The results of the study, published in the January 2005 issue of Neurobiology of Aging, looked at the impact four combinations of behavioural enrichment and supplementation of diet with antioxidants had on a beagle’s ability to learn as the senior dog grew older. The first group had a regular diet and regular experience; the second received a regular diet and enriched experience; the third group a regular experience and an enriched diet; and the fourth group an enriched diet and an enriched experience.

Whereas previous studies have looked at dogs of different ages all at once to identify age-related differences, this investigation followed four groups of dogs over a period of two years. As predicted, the researchers found a dog’s ability to learn declines with age. What they had not anticipated was seeing such a statistically-significant benefit of combining behavioral enrichment and the antioxidant supplementation compared to giving either alone.

“Since humans and dogs have many biological and behavioral parallels, I predict similar results would be attained in people,” notes Milgram. The study was funded by the National Institute of Aging and the U.S. Department of the Army. The following conflict of interest was declared by the authors with respect to publication of this paper: investigator Steven Zicker is an employee of Hill’s Pet Nutrition Inc., which has commercialized the antioxidant fortified food used in the study.