| Abstract: | A total of 240 fourteen-week-olds were rewarded with a pattern of lights and tones for kicking. The reward display interrupted a background of random alternation between two lights and tones. In experiment 1, attention to this background stimulus during a 1-min baseline was assessed using the number of fixations of alternating lights. During 6 min of reward, high-attention subjects showed significantly greater changes in kicking rate from baseline than low-attention subjects. In experiment 2, the proportion of subjects with low attention ratings increased dramatically during an extended 5-min baseline period, and those subjects with low attention ratings at the end of baseline did not show an increase in kicking from baseline to the reward phase, while high-attention subjects did show evidence of learning. Thus, an objective measure of attention, empirically separate from the dependent learning measure, provided a significant prediction of the effectiveness of subsequent reinforcement, and could be manipulated simply by extending the baseline by as little as 4 min. |
