Functioning Imaging of Emergent Learning

描述(由申请人提供)：一(1)定义与发育性残疾相关的学习缺陷的特征是在不具有共同身体特征的刺激之间学习条件或语义关系困难。一个(1)这样的例子是学习单词“2”和数字“2”在语义上是相关的，或者“两个”“2”和“OO”(两个圆圈)可以是同一概念的成员。目前的R03小额拨款提案旨在揭示刺激等值过程的功能神经解剖学。刺激等价性(SE)是在直接训练过程中操纵强化偶然性以建立一组已习得的刺激之间的条件/语义关系的过程，例如，学习如果刺激A，选择刺激B(A：B)的条件关系，以及第二条件关系B：C。在随后的测试中，发现在没有直接训练的情况下，出现了几种新的关系。这些SE关系被称为：对称性(B：A)、传递性(A：C)和等价性(C：A)。为了扩大我们对发育障碍条件/语义学习缺陷的神经解剖学的理解，我们使用fMRI研究了健康成年人的SE过程。结果表明，SE关系在涉及奖赏加工和决策的区域产生了额叶-纹状体的激活。在这项提案中，我们将使用BOLD功能磁共振成像来证明SE关系的区分涉及纹状体和额叶腹侧皮质。我们还将研究额叶-纹状体对通过不同结果(非语言和语言)和不同机制(偶发和指令)建立的SE关系的反应。在健康成人受试者身上获得的结果将有助于我们进一步测试和发展我们的额叶-纹状体受累模型。

DESCRIPTION (provided by applicant): One (1) defining characteristic of learning deficits associated with developmental disabilities is difficulty learning conditional or semantic relations among stimuli that do not share common physical features. One (1) such example is learning that the word "TWO" and the number "2" are semantically related or that "TWO" "2" and "OO" (2 circles) may be members of the same concept. The present R03 small grant proposal is designed to reveal the functional neuroanatomy of a process known as stimulus equivalence. Stimulus equivalence (SE) is a process by which reinforcement contingencies are manipulated during direct training to establish a set of learned conditional/semantic relations among stimuli, for example, learning the conditional relation if stimulus A, select stimulus B (A:B), and a second conditional relation, B:C. During subsequent testing, several new relations have been found to "emerge" without direct training. These SE relations are termed: symmetry (B:A), transitivity (A:C), and equivalence (C:A). To broaden our understanding of the neuroanatomy of conditional/semantic learning deficits in developmental disabilities, we investigated SE processes in healthy adults using fMRI. Results showed SE relations produced frontal-striatal activation in regions implicated in reward processing and decision making. In this proposal, we will use BOLD fMRI to demonstrate that discriminations of SE relations involve the striatum and ventral frontal cortex. We will also investigate frontal-striatal responses to SE relations established through different consequences (nonverbal vs. verbal) and different mechanisms (contingencies vs. instructions). Results obtained with healthy adult subjects will help us to further test and develop our model of frontal-striatal involvement in SE.