Project 5: Exploring the Fear Module of the Human Brain (pg 257)

IpTahreticlounlagr-terermfereonbcjectioveitsofrethlaitsionpsrohiposatol icsotnoscuinoduesrsctaongdnititohne abnradinitsnemtwodoirfkictahtiaotncobnytrloelarhnuinmga.NOfhemaranwitahnd Mineka(2001)提出，人类大脑中存在一个进化的恐惧模块，它起源于漫游- 马里的防御系统。它的特点包括：(A)优先被激活，并且容易 受进化相关威胁刺激的制约；(B)在某种意义上，它相对独立于认知 它可以被自动激活并抵抗意志；以及(C)它由皮质下和皮质下控制 以杏仁核为中心的系统。恐惧模块解释了焦虑症的重要组成部分。 该项目的第一部分使用的是害怕一种动物(例如蛇)但不害怕另一种动物的人 (例如，蜘蛛)作为大脑成像实验的对象，其中有意识地获得这些刺激 被蒙面技术所操纵。对这一人群的进一步实验使用核磁共振 成像和事件相关电位检查视觉搜索过程中大脑对恐惧刺激的反应。进一步 这项工作检查了在行为和药物治疗后恐惧消退时大脑激活的变化 针对恐惧网络的中央节点杏仁核的干预。该项目的第二部分是 致力于由于巴甫洛夫条件反射而修改恐惧模块，这是一种简单的联想 学习。在一系列系统的实验中，人类受试者将会受到生理上的恐惧-- 相关刺激(例如，蛇)或与恐惧无关的刺激(例如，花)被厌恶的无条件刺激。 基本假设是，不同的条件反射测量跟踪恐惧模块和认知学习 条件刺激和非条件刺激之间的关系。这些措施将在决赛中使用 一系列大脑成像研究，其目的是解开与以下相关的大脑结构网络 有意识和无意识地学习简单刺激之间的关系。

IpTahreticlounlagr-terermfereonbcjectioveitsofrethlaitsionpsrohiposatol icsotnoscuinoduesrsctaongdnititohne abnradinitsnemtwodoirfkictahtiaotncobnytrloelarhnuinmga. nOfhemaranwitahnd Mineka (2001) proposed that there is an evolved fear module in the human brain, which originates in roam- malian defence systems. Its characteristics include that it is (a) preferentially activated by, and easily conditioned to, evolutionary relevant threat stimuli; (b) it is relatively independent of cognition in the sense that it can be automatically activated and resists volition; and (c) it is controlled by subcortical and cortical systems centered on the amygdala. The fear module explains important components of anxiety disorder. The first part of the project uses individuals that are fearful of one animal (e.g., snakes) but not of another (e.g., spiders) as subjects in brain imaging experiments in which conscious access to these stimuli is manipulated by masking techniques. Further experiments with this population use magnetic resonance imaging and event-related potentials to examine brain responses to fear stimuli during visual search. Further work examines changes in brain activation as fear subsides after behavioral and pharmacological interventions targeting the central node of the fear network, the amygdala. The second part of the project is devoted to modification of the fear module as a result of Pavlovian conditioning, a kind of simple associative learning. In a systematic series of experiments human subjects will be conditioned to biologically fear- relevant stimuli (e.g., snakes) or fear-irrelevant stimuli (e.g., flowers ) by an aversive unconditioned stimulus. The basic hypothesis is that different measures of conditioning track the fear module and cognitive learning of the relationship between conditioned and unconditioned stimuli. These measures will be used in a final series of brain imaging studies the purpose of which is to unravel networks of brain structures related to conscious and nonconscious learning of the relationships between simple stimuli.