Shimemura Takahiro, Fujita Kazuhisa, Kashimori Yoshiki
Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo 182-8585, Japan.
Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo 182-8585, Japan, Tsuyama National College of Technology, 654-1 Numa, Tsuyama, Okayama 708-8506, Japan and
Chem Senses. 2016 Sep;41(7):579-89. doi: 10.1093/chemse/bjw062. Epub 2016 May 12.
Taste perception is significantly affected by other sensory modalities such as vision, smell, and somatosensation. Such taste sensation elicited by integrating gustatory and other sensory information is referred to as flavor. Although experimental studies have demonstrated the characteristics of flavor perception influenced by other sensory modalities and the involved brain areas, it remains unknown how flavor emerges from the brain circuits. Of the involved brain areas, orbitofrontal cortex (OFC), as well as gustatory cortex (GC), plays a dominant role in flavor perception. We develop here a neural model of gustatory system which consists of GC and OFC networks and examine the neural mechanism of odor-induced taste perception. Using the model, we show that flavor perception is shaped by experience-dependent learning of foods with congruent taste-odor pairs, providing a unique representation of flavor through the interaction between OFC and GC neurons. Our model also shows that feedback signals from OFC to GC modulate the dynamic stability of taste attractors in GC, leading to the enhancement or suppression of taste responses by smells. Furthermore, modeling shows that spatial variability in GC activity evoked by tastants determines to what extent odor enhances congruent taste responses. The results suggest that flavor perception is deeply associated with dynamic stability of GC attractors through the interaction between GC and OFC.
味觉感知会受到视觉、嗅觉和躯体感觉等其他感觉模态的显著影响。这种通过整合味觉和其他感觉信息而引发的味觉被称为风味。尽管实验研究已经证明了受其他感觉模态影响的风味感知特征以及所涉及的脑区，但风味是如何从脑回路中产生的仍然未知。在所涉及的脑区中，眶额皮质（OFC）以及味觉皮质（GC）在风味感知中起主导作用。我们在此开发了一个由GC和OFC网络组成的味觉系统神经模型，并研究气味诱导味觉感知的神经机制。使用该模型，我们表明风味感知是由对具有一致味觉 - 气味配对的食物进行经验依赖性学习塑造的，通过OFC和GC神经元之间的相互作用提供了独特的风味表征。我们的模型还表明，从OFC到GC的反馈信号调节了GC中味觉吸引子的动态稳定性，导致气味对味觉反应的增强或抑制。此外，建模表明由味觉刺激物诱发的GC活动中的空间变异性决定了气味增强一致味觉反应的程度。结果表明，通过GC和OFC之间的相互作用，风味感知与GC吸引子的动态稳定性密切相关。
