Time scales of representation in the human brain: weighing past information to predict future events.
Time scales of representation in the human brain: weighing past information to predict future events.
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人脑中表示的时间尺度：权衡过去的信息以预测未来事件。
DOI：
10.3389/fnhum.2011.00037
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发表时间：
2011
影响因子：
2.9
通讯作者：
Green GG
中科院分区：
文献类型：
--
作者：
Harrison LM;Bestmann S;Rosa MJ;Penny W;Green GG
人类对环境中统计依赖性的估计，以及他们对不确定性的表示，关键取决于数据随时间的整合。因此，过去的事件在多大程度上被用来代表不确定性已经被假定为在皮层上变化。例如，初级视觉皮层对环境中的快速扰动做出反应，而参与执行控制的额叶皮层对这些扰动发生的长期背景进行编码。在这里，我们测试了主要和执行区域是否可以通过它们所代表的过去观察的数量来区分。这是基于衰减依赖模型，该模型对来自马尔可夫过程和贝叶斯模型选择的过去观察进行加权，以测试神经元响应的预测，其特征在于取决于大脑中的位置的不同衰减半衰期。我们显示的分布，分别在初级和次级视觉和额叶皮层的短期和长期衰减功能的大脑反应。我们发现，视觉和顶叶的反应从过去的负担中释放出来，能够对事件的波动做出敏捷的反应。相比之下，锋区更关心的是较长时间尺度上的平均趋势，其中嵌入了局部变化。具体来说，我们提供的证据表明，时间梯度表示上下文内的前额叶皮层，并可能超越包括初级感觉和关联领域。
The estimates that humans make of statistical dependencies in the environment and therefore their representation of uncertainty crucially depend on the integration of data over time. As such, the extent to which past events are used to represent uncertainty has been postulated to vary over the cortex. For example, primary visual cortex responds to rapid perturbations in the environment, while frontal cortices involved in executive control encode the longer term contexts within which these perturbations occur. Here we tested whether primary and executive regions can be distinguished by the number of past observations they represent. This was based on a decay-dependent model that weights past observations from a Markov process and Bayesian Model Selection to test the prediction that neuronal responses are characterized by different decay half-lives depending on location in the brain. We show distributions of brain responses for short and long term decay functions in primary and secondary visual and frontal cortices, respectively. We found that visual and parietal responses are released from the burden of the past, enabling an agile response to fluctuations in events as they unfold. In contrast, frontal regions are more concerned with average trends over longer time scales within which local variations are embedded. Specifically, we provide evidence for a temporal gradient for representing context within the prefrontal cortex and possibly beyond to include primary sensory and association areas.
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DOI：
10.1196/annals.1390.022
发表时间：
2007-01-01
期刊：
REWARD AND DECISION MAKING IN CORTICOBASAL GANGLIA NETWORKS
影响因子：
--
作者：
O'Doherty, John P.;Hampton, Alan;Kim, Hackjin
通讯作者：
Kim, Hackjin
影响因子：
4.3
作者：
Kiebel SJ;Daunizeau J;Friston KJ
通讯作者：
Friston KJ
影响因子：
7.8
作者：
Brodersen, Kay H.;Penny, Will D.;Stephan, Klaas E.
通讯作者：
Stephan, Klaas E.
影响因子：
2.9
作者：
Forstmann BU;Brown S;Dutilh G;Neumann J;Wagenmakers EJ
通讯作者：
Wagenmakers EJ
影响因子：
5.3
作者：
Hyafil, Alexandre;Summerfield, Christopher;Koechlin, Etienne
通讯作者：
Koechlin, Etienne