Dietary restriction: effects on radial maze learning and lipofuscin pigment deposition in the hippocampus and frontal cortex.

Previous studies have shown increased life span and decreased lipofuscin deposition in brain structures when both premature and young adult animals are calorically restricted of an otherwise nutritionally adequate diet. Three-months-old C57BL/6 mice were subjected to 12 months of caloric restriction (2 g/day), and subsequently exposed to a radial maze learning paradigm. Mice in the diet restriction group showed faster learning and higher asymptotic performance on the radial maze task, as well as lower lipofuscin deposition in the neurons of hippocampus and frontal cortex relative to control mice fed ad libitum. The results suggest that dietary restriction has effects on radial maze learning, and this improved behavioral performance was associated with significant reduction in lipofuscin pigment deposition in the neurons of hippocampus and frontal cortex.