Lalumiere Ryan T
Department of Psychology, University of Iowa Iowa City, IA, USA.
Front Behav Neurosci. 2014 Mar 26;8:107. doi: 10.3389/fnbeh.2014.00107. eCollection 2014.
Studies of amygdala functioning have occupied a significant place in the history of understanding how the brain controls behavior and cognition. Early work on the amygdala placed this small structure as a key component in the regulation of emotion and affective behavior. Over time, our understanding of its role in brain processes has expanded, as we have uncovered amygdala influences on memory, reward behavior, and overall functioning in many other brain regions. Studies have indicated that the amygdala has widespread connections with a variety of brain structures, from the prefrontal cortex to regions of the brainstem, that explain its powerful influence on other parts of the brain and behaviors mediated by those regions. Thus, many optogenetic studies have focused on harnessing the powers of this technique to elucidate the functioning of the amygdala in relation to motivation, fear, and memory as well as to determine how the amygdala regulates activity in other structures. For example, studies using optogenetics have examined how specific circuits within amygdala nuclei regulate anxiety. Other work has provided insight into how the basolateral and central amygdala nuclei regulate memory processing underlying aversive learning. Many experiments have taken advantage of optogenetics' ability to target either genetically distinct subpopulations of neurons or the specific projections from the amygdala to other brain regions. Findings from such studies have provided evidence that particular patterns of activity in basolateral amygdala (BLA) glutamatergic neurons are related to memory consolidation processes, while other work has indicated the critical nature of amygdala inputs to the prefrontal cortex and nucleus accumbens (NA) in regulating behavior dependent on those downstream structures. This review will examine the recent discoveries on amygdala functioning made through experiments using optogenetics, placing these findings in the context of the major questions in the field.
杏仁核功能的研究在理解大脑如何控制行为和认知的历史中占据了重要地位。早期对杏仁核的研究将这个小结构置于情绪和情感行为调节的关键组成部分。随着时间的推移，我们对其在大脑过程中作用的理解不断扩展，因为我们发现杏仁核对记忆、奖励行为以及许多其他脑区的整体功能都有影响。研究表明，杏仁核与从额叶前皮质到脑干区域的各种脑结构有着广泛的联系，这解释了它对大脑其他部分以及由这些区域介导的行为的强大影响。因此，许多光遗传学研究专注于利用这项技术的力量来阐明杏仁核在动机、恐惧和记忆方面的功能，以及确定杏仁核如何调节其他结构中的活动。例如，使用光遗传学的研究已经考察了杏仁核核团内的特定回路如何调节焦虑。其他研究工作则深入了解了基底外侧杏仁核和中央杏仁核核团如何调节厌恶学习背后的记忆处理。许多实验利用了光遗传学针对基因上不同的神经元亚群或从杏仁核到其他脑区的特定投射的能力。这些研究的结果提供了证据，表明基底外侧杏仁核（BLA）谷氨酸能神经元的特定活动模式与记忆巩固过程有关，而其他研究则表明杏仁核输入到额叶前皮质和伏隔核（NA）在调节依赖于这些下游结构的行为方面的关键性质。这篇综述将审视通过光遗传学实验在杏仁核功能方面的最新发现，并将这些发现置于该领域的主要问题背景中。
