Research Centre for Brain and Behaviour, School of Psychology, Liverpool John Moores University, Liverpool, UK.
Department of Psychology, University of Liverpool, Liverpool, UK.
Chem Senses. 2021 Jan 1;46. doi: 10.1093/chemse/bjaa078.
Taste perception has been reported to vary with changes in affective state. Distortions of taste perception, including blunted recognition thresholds, intensity, and hedonic ratings have been identified in those suffering from depressive disorders. Serotonin is a key neurotransmitter implicated in the etiology of anxiety and depression; systemic and peripheral manipulations of serotonin signaling have previously been shown to modulate taste detection. However, the specific effects of central serotonin function on taste processing have not been widely investigated. Here, in a double-blind placebo-controlled study, acute tryptophan depletion was used to investigate the effect of reduced central serotonin function on taste perception. Twenty-five female participants aged 18-28 attended the laboratory on two occasions at least 1 week apart. On one visit, they received a tryptophan depleting drink and on the other, a control drink was administered. Approximately, 6 h after drink consumption, they completed a taste perception task which measured detection thresholds and supra-threshold perceptions of the intensity and pleasantness of four basic tastes (sweet, sour, bitter, and salt). While acutely reducing central levels of serotonin had no effect on the detection thresholds of sweet, bitter, or sour tastes, it significantly enhanced detection of salt. For supra-threshold stimuli, acutely reduced serotonin levels significantly enhanced the perceived intensity of both bitter and sour tastes and blunted pleasantness ratings of bitter quinine. These findings show manipulation of central serotonin levels can modulate taste perception and are consistent with previous reports that depletion of central serotonin levels enhances neural and behavioral responsiveness to aversive signals.
味觉感知已被报道会随情绪状态的变化而变化。在患有抑郁障碍的人群中，已发现味觉感知的扭曲，包括识别阈值、强度和愉悦度的降低。血清素是一种与焦虑和抑郁发病机制有关的关键神经递质；先前的研究表明，对血清素信号的全身和外周操作可以调节味觉检测。然而，中枢血清素功能对味觉处理的具体影响尚未得到广泛研究。在这里，在一项双盲安慰剂对照研究中，急性色氨酸耗竭被用于研究中枢血清素功能降低对味觉感知的影响。25 名年龄在 18-28 岁的女性参与者在至少相隔一周的两次访问中到实验室就诊。在一次访问中，她们接受了色氨酸耗竭饮料，而在另一次访问中，给予了对照饮料。在饮料摄入后约 6 小时，她们完成了一项味觉感知任务，该任务测量了四种基本味觉（甜、酸、苦和咸）的检测阈值和超阈值感知强度和愉悦度。虽然急性降低中枢血清素水平对甜味、苦味或酸味的检测阈值没有影响，但它显著增强了对咸味的检测。对于超阈值刺激，急性降低血清素水平显著增强了苦味和酸味的感知强度，并使苦味奎宁的愉悦度评分降低。这些发现表明，中枢血清素水平的操纵可以调节味觉感知，并且与先前的报告一致，即中枢血清素水平的耗竭增强了对厌恶信号的神经和行为反应性。
