Ganis Giorgio, Thompson William L, Kosslyn Stephen M
Department of Psychology, Harvard University, 33 Kirkland St., Cambridge, MA 02138, USA.
Cogn Affect Behav Neurosci. 2005 Jun;5(2):235-45. doi: 10.3758/cabn.5.2.235.
We used functional magnetic resonance imaging to study practice effects in different mental imagery tasks. The study was designed to address three general questions: First, are the results of standard group-based analyses the same as those of a regression method in which brain activation changes over individual participants are used to predict task performance changes? With respect to the effects of practice, the answer was clear: Group-based analyses produced different results from regression-based individual-differences analyses. Second, are all brain areas that predict practice effects consistently activated across participants? Again, the answer was clear: Most areas that predicted the effects of practice on performance were not activated consistently over participants. Finally, does practice affect different areas in different ways for different people in different tasks? The answer was again clear: The areas that predicted changes in performance with practice varied for the different tasks, but this was more dramatically and clearly revealed by the individual-differences analyses. In short, individual-differences analyses provided insights into the relation between changes in brain activation and changes in accompanying performance, and these insights were not provided by standard group-based analyses.
我们使用功能磁共振成像来研究不同心理意象任务中的练习效应。该研究旨在解决三个一般性问题：第一，基于标准组分析的结果与回归方法的结果是否相同，在回归方法中，个体参与者大脑激活的变化用于预测任务表现的变化？关于练习效应，答案很明确：基于组的分析产生的结果与基于回归的个体差异分析不同。第二，所有预测练习效应的脑区在参与者中是否一致被激活？答案同样明确：大多数预测练习对表现影响的区域在参与者中并非一致被激活。最后，练习在不同任务中对不同的人是否以不同方式影响不同区域？答案还是明确的：预测练习后表现变化的区域因不同任务而异，但这在个体差异分析中更显著且清晰地显现出来。简而言之，个体差异分析为大脑激活变化与伴随表现变化之间的关系提供了见解，而这些见解是基于标准组的分析所无法提供的。
