De Pauw K, Roelands B, Van Cutsem J, Marusic U, Torbeyns T, Meeusen R
Research Group Human Physiology, Faculty of Physical Education and Physical Therapy, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium.
Fund for Scientific Research Flanders (FWO), Brussels, Belgium.
Psychopharmacology (Berl). 2017 Jan;234(1):53-62. doi: 10.1007/s00213-016-4435-2. Epub 2016 Sep 23.
A direct link between the mouth cavity and the brain for glucose (GLUC) and caffeine (CAF) has been established. The aim of this study is to determine whether a direct link for both substrates also exist between the nasal cavity and the brain.
Ten healthy male subjects (age 22 ± 1 years) performed three experimental trials, separated by at least 2 days. Each trial included a 20-s nasal spray (NAS) period in which solutions placebo (PLAC), GLUC, or CAF were provided in a double-blind, randomized order. During each trial, four cognitive Stroop tasks were performed: two familiarization trials and one pre- and one post-NAS trial. Reaction times and accuracy for different stimuli (neutral, NEUTR; congruent, CON; incongruent INCON) were determined. Electroencephalography was continuously measured throughout the trials. During the Stroop tasks pre- and post-NAS, the P300 was assessed and during NAS, source localization was performed using standardized low-resolution brain electromagnetic tomography (sLORETA).
NAS activated the anterior cingulate cortex (ACC). CAF-NAS also increased θ and β activity in frontal cortices. Furthermore, GLUC-NAS increased the β activity within the insula. GLUC-NAS also increased the P300 amplitude with INCON (P = 0.046) and reduced P300 amplitude at F3-F4 and P300 latency at CP1-CP2-Cz with NEUTR (P = 0.001 and P = 0.016, respectively). The existence of nasal bitter and sweet taste receptors possibly induce these brain responses.
Greater cognitive efficiency was observed with GLUC-NAS. CAF-NAS activated cingulate, insular, and sensorymotor cortices, whereas GLUC-NAS activated sensory, cingulate, and insular cortices. However, no effect on the Stroop task was found.
已证实口腔与大脑之间存在葡萄糖（GLUC）和咖啡因（CAF）的直接联系。本研究的目的是确定鼻腔与大脑之间是否也存在这两种底物的直接联系。
10名健康男性受试者（年龄22±1岁）进行了三项实验，每次实验间隔至少2天。每次实验包括一个20秒的鼻腔喷雾（NAS）阶段，在此期间以双盲、随机顺序提供安慰剂（PLAC）、GLUC或CAF溶液。在每次实验中，进行了四项认知斯特鲁普任务：两项熟悉试验以及一项NAS前和一项NAS后的试验。确定了对不同刺激（中性，NEUTR；一致，CON；不一致，INCON）的反应时间和准确性。在整个实验过程中持续测量脑电图。在NAS前后的斯特鲁普任务期间，评估P300，并在NAS期间，使用标准化低分辨率脑电磁断层扫描（sLORETA）进行源定位。
NAS激活了前扣带回皮层（ACC）。CAF-NAS还增加了额叶皮层的θ和β活动。此外，GLUC-NAS增加了岛叶内的β活动。GLUC-NAS还增加了INCON时的P300波幅（P = 0.046），并降低了NEUTR时F3-F4处的P300波幅以及CP1-CP2-Cz处的P300潜伏期（分别为P = 0.001和P = 0.016）。鼻腔苦味觉和甜味觉受体的存在可能诱发了这些大脑反应。
观察到GLUC-NAS具有更高的认知效率。CAF-NAS激活了扣带回、岛叶和感觉运动皮层，而GLUC-NAS激活了感觉、扣带回和岛叶皮层。然而，未发现对斯特鲁普任务有影响。
