den Ouden H E M, Frith U, Frith C, Blakemore S-J
Institute of Cognitive Neuroscience, Department of Psychology, University College London, UK.
Neuroimage. 2005 Dec;28(4):787-96. doi: 10.1016/j.neuroimage.2005.05.001. Epub 2005 Jun 17.
In this fMRI study, we investigated the convergence of underlying neural networks in thinking about a scenario involving one's own intentional action and its consequences and setting up and holding in mind an intention to act. A factorial design was employed comprising two factors: i. Causality (intentional or physical events) and ii. Prospective Memory (present or absent). In each condition, subjects answered questions about various hypothetical scenarios, which related either to the link between the subject's own intentions and consequential actions (Intentional Causality) or to the link between a natural, physical event and its consequences (Physical Causality). A prospective memory task was embedded in half the blocks. In this task, subjects were required to keep in mind an intention (to press a key on seeing a red stimulus background) whilst carrying out the ongoing Causality task. Answering questions about intentional causality versus physical causality activated a network of regions that have traditionally been associated with Theory of Mind, including the medial prefrontal cortex (mPFC), the superior temporal sulcus and the temporal poles bilaterally. In addition, the precuneus bordering with posterior cingulate cortex, an area involved in self-awareness and self-related processing, was activated more when thinking about intentional causality. In the prospective memory task, activations were found in the right parietal cortex, frontopolar cortex (BA 10) and precuneus. Different subregions within the precuneus/posterior cingulate cortex were activated in both main effects of intentional causality and prospective memory. Therefore, the precuneus/posterior cingulate cortex subserves separately thinking about one's own intentions and consequent actions and bearing in mind an intention to make an action. Previous studies have shown that prospective memory, requiring the formation of an intention and the execution of a corresponding action, is associated with decreased activation in the dorsal mPFC, close to the region activated in Theory of Mind tasks. Here, we found that holding in mind an intention to act and at the same time thinking about an intentional action led to reduced activity in a dorsal section of the mPFC. This was a different region from a more anterior, inferior dorsal mPFC region that responded to intentional causality. This suggests that different regions of mPFC play different roles in thinking about intentions.
在这项功能磁共振成像（fMRI）研究中，我们调查了在思考一个涉及自身有意行动及其后果的情景以及设定并牢记一个行动意图时，潜在神经网络的汇聚情况。我们采用了析因设计，包括两个因素：i. 因果关系（有意或物理事件）和ii. 前瞻性记忆（存在或不存在）。在每种条件下，受试者回答关于各种假设情景的问题，这些问题要么与受试者自身意图和后续行动之间的联系（有意因果关系）有关，要么与自然物理事件及其后果之间的联系（物理因果关系）有关。前瞻性记忆任务被嵌入到一半的实验块中。在这个任务中，受试者在执行正在进行的因果关系任务时，需要牢记一个意图（在看到红色刺激背景时按下一个键）。回答关于有意因果关系与物理因果关系的问题激活了一个传统上与心理理论相关的区域网络，包括内侧前额叶皮层（mPFC）、颞上沟以及双侧颞极。此外，与后扣带回皮层相邻的楔前叶，一个涉及自我意识和自我相关加工的区域，在思考有意因果关系时被更强烈地激活。在前瞻性记忆任务中，在右侧顶叶皮层、额极皮层（BA 10）和楔前叶发现了激活。有意因果关系和前瞻性记忆的两个主要效应均激活了楔前叶/后扣带回皮层内不同的亚区域。因此，楔前叶/后扣带回皮层分别服务于对自身意图和后续行动的思考以及牢记一个行动意图。先前的研究表明，需要形成一个意图并执行相应行动的前瞻性记忆与背侧mPFC的激活减少有关，该区域靠近心理理论任务中激活的区域。在这里，我们发现牢记一个行动意图并同时思考一个有意行动会导致mPFC背侧部分的活动减少。这是一个与对有意因果关系做出反应的更靠前、靠下的背侧mPFC区域不同的区域。这表明mPFC的不同区域在思考意图时发挥不同的作用。
