Department of Women's and Children's Health and Stockholm Brain Institute, Retzius väg 8, Karolinska Institutet, SE-171 76 Stockholm, Sweden.
Neuroimage. 2012 Jan 2;59(1):772-80. doi: 10.1016/j.neuroimage.2011.07.016. Epub 2011 Jul 19.
To what extent free response generation in different tasks uses common and task-specific neurocognitive processes has remained unclear. Here, we investigated overlap and differences in neural activity during musical improvisation and pseudo-random response generation. Brain activity was measured using fMRI in a group of professional classical pianists, who performed musical improvisation of melodies, pseudo-random key-presses and a baseline condition (sight-reading), on either two, six or twelve keys on a piano keyboard. The results revealed an extensive overlap in neural activity between the two generative conditions. Active regions included the dorsolateral and dorsomedial prefrontal cortices, inferior frontal gyrus, anterior cingulate cortex and pre-SMA. No regions showed higher activity in improvisation than in pseudo-random generation. These findings suggest that the activated regions fulfill generic functions that are utilized in different types of free generation tasks, independent of overall goal. In contrast, pseudo-random generation was accompanied by higher activity than improvisation in several regions. This presumably reflects the participants' musical expertise as well as the pseudo-random generation task's high load on attention, working memory, and executive control. The results highlight the significance of using naturalistic tasks to study human behavior and cognition. No brain activity was related to the size of the response set. We discuss that this may reflect that the musicians were able to use specific strategies for improvisation, by which there was no simple relationship between response set size and neural activity.
在多大程度上，不同任务中的自由响应生成使用共同和特定于任务的神经认知过程仍不清楚。在这里，我们研究了音乐即兴创作和伪随机响应生成过程中神经活动的重叠和差异。我们使用 fMRI 测量了一组专业古典钢琴家的大脑活动，他们在钢琴键盘上演奏了旋律的即兴创作、伪随机按键和基线条件（视奏），分别演奏了两个、六个或十二个键。结果显示，两种生成条件之间的神经活动有很大的重叠。活跃的区域包括背外侧和背内侧前额叶皮层、下额回、前扣带皮层和前 SMA。没有发现即兴创作比伪随机生成的区域活动更高。这些发现表明，激活的区域履行了通用功能，这些功能在不同类型的自由生成任务中都得到了利用，而不受总体目标的影响。相比之下，伪随机生成比即兴创作在几个区域中伴随着更高的活动。这可能反映了参与者的音乐专业知识以及伪随机生成任务对注意力、工作记忆和执行控制的高要求。结果强调了使用自然任务来研究人类行为和认知的重要性。没有脑活动与响应集的大小有关。我们认为，这可能反映出音乐家能够使用特定的即兴创作策略，因此响应集大小和神经活动之间没有简单的关系。
