Introduction

This study aimed to meta-analyze the functional magnetic resonance imaging (fMRI) data and compare the brain activations from gustatory studies with different stimulus delivery methods.

Methods

Published fMRI studies were included into the analysis if they evaluated the brain responses to liquid tastants or food among healthy subjects. Studies were coded into three groups: stimulus removed from the mouth by suction without the need to swallow, swallowing without controlling for its confounds, and swallowing with controlling for its confounds.

Results

Forty-five studies that comprised of a total of 1498 participants fulfilled the inclusion criteria. Suction studies activated the posterior cingulate. Swallowing studies covered multiple brain regions including the anterior and middle insula, the precentral gyrus, and the postcentral gyrus.

Conclusions

For the contrast analysis between swallowing studies with and without controlling for the confounds, the former group had larger brain activation mainly at the anterior and middle insula and the thalamus, whereas the latter group had larger brain activation mainly at the anterior cingulate, precentral gyrus, and postcentral gyrus.

Implications

Compared to studies that did not control for confounds of swallowing, studies that controlled for swallowing demonstrated heightened responses at the insula and reduced responses at the sensorimotor cortex.

中文翻译：

---

吞咽和不吞咽时大脑对食物或调味品的反应差异：功能磁共振成像 (fMRI) 研究的荟萃分析

介绍

本研究旨在对功能磁共振成像 (fMRI) 数据进行元分析，并比较来自味觉研究的大脑激活与不同的刺激传递方法。

方法

如果已发表的 fMRI 研究评估了健康受试者对液体促味剂或食物的大脑反应，则将其纳入分析。研究分为三组：通过吸力从口腔中去除刺激而不需要吞咽，吞咽而不控制其混淆，以及控制其混淆吞咽。

结果

由 1498 名参与者组成的 45 项研究符合纳入标准。吸力研究激活了后扣带回。吞咽研究涵盖了多个大脑区域，包括前岛和中岛、中央前回和中央后回。

结论

对于有和没有控制混杂因素的吞咽研究之间的对比分析，前一组的脑激活主要在前岛和中岛以及丘脑，而后一组的脑激活主要在前扣带回、中央前回、和中央后回。

影响

与没有控制吞咽混淆的研究相比，控制吞咽的研究表明岛叶的反应增强，感觉运动皮层的反应降低。