Background Area, Pattern Height and Discrimination Learning for the Hooded Rat: Preliminary Findings and Methodological Comments

Abstract

To separate effects of background size from pattern height, hooded rats were trained with: (a) patterns centered on large backgrounds, (b) patterns lowered on large backgrounds, (c) patterns centered on small backgrounds. For the first condition, patterns were higher than for the last two conditions. For the last 2 conditions, background areas were different, but pattern heights were identical. No differences in learning were seen for these last 2 conditions and both resulted in better learning than the centered patterns on large backgrounds. It was concluded that decreasing background size, when patterns are centered, improves learning indirectly by either (a) decreasing pattern height or (b) increasing the contiguity of S's response to critical pattern features.