CRCNS: Where to Look Next? Modeling Eye Movements in Normal and Impaired Vision

描述(申请人提供)：这项工作的目标是开发一个解释性和预测性的正常和低视力下的眼动规划模型，用于客观地设计和衡量低视力康复的有效性。在之前的项目期间，我们开发了一种眼动效率的定量测量方法，发现黄斑病变患者的低效不能简单地用他们的中央视野丧失的程度来解释。因此，肯定还有其他因素影响这些患者的眼球运动策略。在这项建议中，我们进一步发展了我们的计算模型，以预测人类的眼跳行为，除了注视位置。前两个目标将经验性地衡量运动误差如何以及是否限制了扫视的幅度和方向。第三个目标寻求改进之前的努力，即在眼动产生和刺激不确定性之间建立自然的因果联系。最终目的是应用修订后的模型来探索黄斑病变患者眼球运动效率低下的一个可能来源：我们测试了这样的假设，即患者保留了他们视力的“正常”内部模板，而不是他们中央视野损失的真实表示。这一假设与临床观察相一致，即患者通常只有在双侧暗点超过10度时才开始抱怨自己的视力，而且教授“暗点意识”可以改善功能结果。我们的计算模型将继续为挑战临床假说提供一个概念框架，最终目标是将低视力康复实践转化为康复科学。

DESCRIPTION (provided by applicant): The goal of this work is to develop an explanatory and predictive model of eye movement planning in normal and low vision that can be used to objectively design and measure the effectiveness of low vision rehabilitation. In the previous project period, we developed a quantitative measure of eye movement efficiency and found that inefficiencies among maculopathy patients could not be explained simply by the extent of their central field loss. Thus, there must be additional factors that impair the eye movement strategies in these patients. In this proposal, we further develop our computational model to predict human saccade behavior in addition to fixation placement. The first two aims will empirically measure how and whether motor error limits saccade amplitude and direction. The third aim seeks to improve upon previous endeavors to establish a natural causal link between eye movement generation and stimulus uncertainty. The final aim applies the revised model to probe a possible source of eye movement inefficiency in maculopathy patients: we test the hypothesis that patients retain a "normal" internal template of their vision instead of a veridical representation of their central field loss. This hypothesis is consistent with clinical observations that patients' typically begin complaining about their vision only when bilateral scotomas exceed 10deg, and that teaching "scotoma awareness" can improve functional outcome. Our computational model will continue to provide a conceptual framework for challenging clinical hypotheses, with the eventual goal of transforming low vision rehabilitation practice into rehabilitation science.