Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK.
Cereb Cortex. 2013 Jan;23(1):1-11. doi: 10.1093/cercor/bhr363. Epub 2012 Jan 23.
Detection and appropriate reaction to sudden and intense events happening in the sensory environment is crucial for survival. By combining Bayesian model selection with dynamic causal modeling of functional magnetic resonance imaging data, a novel analysis approach that allows inferring the causality between neural activities in different brain areas, we demonstrate that salient sensory information reaches the multimodal cortical areas responsible for its detection directly from the thalamus, without being first processed in primary and secondary sensory-specific areas. This direct thalamocortical transmission of multimodal salient information is parallel to the processing of finer stimulus attributes, which are transmitted in a modality-specific fashion from the thalamus to the relevant primary sensory areas. Such direct thalamocortical connections bypassing primary sensory cortices provide a fast and efficient way for transmitting information from subcortical structures to multimodal cortical areas, to allow the early detection of salient events and, thereby, trigger immediate and appropriate behavior.
检测和对感官环境中突发和强烈事件的适当反应对生存至关重要。通过将贝叶斯模型选择与功能磁共振成像数据的动态因果建模相结合，我们提出了一种新的分析方法，该方法可以推断不同大脑区域之间的神经活动的因果关系。研究结果表明，显著的感觉信息直接从丘脑到达负责其检测的多模态皮质区域，而无需首先在初级和次级感觉特异性区域进行处理。这种多模态显著信息的直接丘脑皮质传递与更精细刺激属性的处理平行，这些属性以特定于模态的方式从丘脑传递到相关的初级感觉区域。这种绕过初级感觉皮层的直接丘脑皮质连接为从皮质下结构向多模态皮质区域传输信息提供了一种快速有效的方式，以便早期检测到显著事件，并触发即时和适当的行为。
