Switch independent task representations in frontal and parietal cortex

A collection of 40 brain maps. Each brain map is a 3D array of values representing properties of the brain at different locations.

### Collection description

<p>Alternating between two tasks is effortful and impairs performance. Previous functional magnetic resonance imaging (fMRI) studies have found increased activity in fronto-parietal cortex when task switching is required. One possibility is that the additional control demands for switch trials are met by strengthening task representations in the human brain. Alternatively, on switch trials the residual representation of the previous task might impede the buildup of a neural task representation. This would predict weaker task representations on switch trials, thus also explaining the performance costs. To test this, participants were cued to perform one of two similar tasks, with the task being repeated or switched between successive trials. MVPA was used to test which regions encode the tasks and whether this encoding differs between switch and repeat trials. As expected, we found information about task representations in frontal and parietal cortex, but there was no difference in the decoding accuracy of task-related information between switch and repeat trials. Using cross-classification we found that the fronto-parietal cortex encodes tasks using a similar spatial pattern in switch and repeat trials. Thus, task representations in frontal and parietal cortex are largely switch-independent. We found no evidence that neural information about task representations in these regions can explain behavioral costs usually associated with task switching.</p>

本数据集包含40幅大脑图谱。每一幅大脑图谱均由三维数值数组构成，该数组代表了大脑在不同位置的属性。

### 集合描述

在交替执行两项任务时，不仅费力且会损害表现。既往的功能磁共振成像（fMRI）研究指出，当需要切换任务时，前额叶皮层和顶叶皮层的活动会增强。一种可能的解释是，在切换试验中，额外的控制需求通过加强人类大脑中的任务表征得以满足。或者，在切换试验中，先前任务的残余表征可能会阻碍神经任务表征的建立。这预测了切换试验中任务表征的减弱，从而也解释了表现成本。为验证此假设，研究人员提示参与者执行两项相似的任务之一，任务在连续试验中重复或切换。多变量模式分析（MVPA）被用于检验哪些区域编码任务，以及这种编码在切换和重复试验中是否存在差异。正如预期，我们发现在额叶和顶叶皮层中存在关于任务表征的信息，但在切换和重复试验中任务相关信息的解码精度上并未发现差异。通过交叉分类分析，我们发现前额叶皮层和顶叶皮层在切换和重复试验中使用相似的空间模式来编码任务。因此，额叶和顶叶皮层中的任务表征在很大程度上是切换无关的。我们没有发现任何证据表明，这些区域中关于任务表征的神经信息可以解释通常与任务切换相关联的行为成本。