Memory, cognitive function and behavior changes of rats with β-amyloid infusion. Latency time to enter the dark room in passive avoidance test (A) and the latency to locate zone with the platform during (B) and the period to stay in the platform zone on day 5 during water maze test (C) were given. The β-amyloid (25–35) infused diabetic rats fed high fat diets with 1% dextrin (AD-CON), 1% less pungent red pepper (AD-LSP), moderate pungent red pepper (AD-MSP) or severe pungent red pepper (AD-SSP) for 28 days. The β-amyloid (35–25) infused rats fed high fat diets with 1% dextrin (Non-AD-CON). Each dot and bar represents Means ± SD (n = 20). abcdDifferent letters on the bars indicate significant differences at P < 0.05.