Learned changes in odour experience: a neural, genetic and behavioural analysis

咖啡因是消费最广泛的精神活性药物，也是许多食品和饮料中发现的一种食品添加剂。最近，人们对过量摄入含有高咖啡因和糖的能量饮料表示担忧，特别是在年轻消费者中。到目前为止，研究(有些是由约曼斯/斯塔福德/帕克完成的)已经证明了咖啡因在情绪、认知和偏好方面的撤退效应的特征，但更根本的问题仍然是未知的，即咖啡因摄入推动口味喜好变化的神经机制。了解这一点很重要，因为它将揭示对咖啡因的喜好是如何与特定的大脑通路(腺苷)联系在一起的，从而导致可塑性和成瘾问题。这个项目将结合进一步的行为特征，通过与糖和咖啡因的联系来改变人类的味道体验，并首次使用fMRI研究神经对咖啡因或糖相关的气味和味道的反应变化。此外，我们还将研究已知的腺苷受体基因多态性在个体差异对咖啡因反应中的潜在作用。学生将接受最先进的人类学习和精神药理学方面的培训，包括味觉和嗅觉的功能磁共振测试(在苏塞克斯)，气味和味觉的行为分析和辨别(在朴茨茅斯)，以及人类行为的基因分析。这些结果与理解能量饮料过度消费的驱动因素有关，并可能对政策和产品制定产生影响。

Caffeine is the most widely consumed psychoactive drug and is also a food additive found in many foods and beverages.Recent concerns have been raised about the excess consumption of energy drinks containing high levels of caffeine and sugar, particularly in younger consumers. To date, research (some completed by Yeomans/Stafford/Parker) has demonstrated the characteristics of caffeine in terms of its withdrawal effects on mood, cognition and preference, but the more fundamental questions on the neural mechanisms underlying changes in flavour liking driven by caffeine ingestion remain unknown. This is important to understand as it will reveal how acquiring a liking for caffeine is linked to particular brain pathways (inc adenosine) and thereby contribute to questions of plasticity and addiction. This project will combine further behavioural characterisation of changes in human flavour experience through association with sugars and caffeine with the first ever studies of neural changes in response to caffeine- or sugar-associated odours and tastes using fMRI. Additionally, we will examine the potential role of known polymorphisms in adenosine receptors in individual differences in response to caffeine. The student will receive state-of-the-art training in human learning and psychopharmacology, in fMRI testing with tastes and smells (at Sussex), behavioural analyses of odour and taste detection and discrimination (at Portsmouth) and genetic analysis of human behaviour. The outcomes have relevance to the understanding of drivers of overconsumption of energy drinks, with potential impact on policy and product formulation.