Strengthening the link between subjective and objective visual acuity

视力测试是一项基本的眼科检查，与诊断、医学-法律决策以及临床和基础科学的研究进展具有显著的相关性。重要的是，确定视力的标准程序是“主观”测试，其中结果的有效性主要取决于患者反应的可靠性。在某些患者群体中，由于没有能力或缺乏意愿，这是一种严重的混淆，具有深远的后果。虽然基于视觉诱发电位（VEP）的“客观”视敏度测试已被证明是有价值的，但它存在严重的局限性，这些局限性损害了VEP视敏度估计的可靠性。我们最近的研究进展表明，这些挑战可以克服与敏锐度测试的方法，是基于认知事件相关的潜在组件“P300”。基于这项研究的势头，目前的建议旨在改进客观视力测试，以促进电生理视力评估的广泛应用。我们将通过结合双模态神经成像[P300/VEP]和磁共振成像的双中心方法来解决传统客观视力测试的挑战和局限性（MRI和fMRI）]和心理物理学，目标是设计一个创新的客观敏锐度测试方案。具体地说，我们计划测试250名视力障碍患者，直到法律的失明。我们将评估主观和基于P300和VEP的敏锐度之间的差异，这些差异由（i）疾病类型，（ii）空间刺激特征，（iii）皮质约束和（iv）时间动态引起。我们将利用这些见解（v）建立一个综合框架，用于临床和研究应用中超越最先进的电生理敏锐度评估。所涉及的方面将包括中央视力丧失和注视行为的相互作用的影响，扭曲的视觉，在自定进度的心理物理学与非自定进度的客观读数的固有差异，以及认知事件相关电位和基于fMRI的视野敏锐度地图的范围。这将促进客观视力测试的应用和我们对客观视力测试的基本理解。该项目的总体目标是大幅提高客观视力评估的稳健性，可靠性和特异性，该项目非常关注实际相关性，旨在将发现转化为临床常规，并识别治疗成功读出的生物标志物。同时，这些实验将揭示健康和患病人类视觉系统中结构-功能相互作用的重要方面。

Visual acuity testing is a fundamental ophthalmological examination with eminent relevance for diagnostics, medico-legal decisions, and research progress in clinical and basic science. Importantly, the standard procedure to determine visual acuity is ‘subjective’ testing, where the validity of the results critically depends on the reliability of the patient’s responses. In certain groups of patients this is, due to inability or lack of willingness, a serious confound with far reaching consequences. While ‘objective’ visual acuity testing based on visual evoked potentials (VEPs) has proven to be of value, it is suffering from severe limitations that compromise the reliability of the VEP-acuity estimates. Our recent research advances indicate that these challenges can be overcome with an acuity-testing approach that is based on the cognitive event-related-potential component ‘P300’. Based on the momentum of this research, the current proposal aims to improve objective acuity testing in order to stimulate the wide-spread use of electrophysiological visual acuity estimation.We will address the challenges and limitations of conventional objective acuity testing with a bicentric approach combining bi-modal neuro-imaging [P300/VEP and magnetic resonance imaging (MRI & fMRI)] and psychophysics with the goal to devise an innovative objective acuity-testing scheme. Specifically, we plan to test 250 patients with visual impairment down to legal blindness. We will assess discrepancies between subjective and P300- and VEP-based acuity caused by (i) disease-type, (ii) spatial stimulus characteristics, (iii) cortical constraints, and (iv) temporal dynamics. We will use these insights to (v) establish an integrated framework for beyond-state-of-the-art electrophysiological acuity assessment in clinical and research applications. The aspects addressed will include effects of the interplay of central visual loss and fixation behavior, distorted vision, inherent differences in self-paced psychophysics vs non-self-paced objective readouts, and the scope of cognitive event related potentials and fMRI-based visual field acuity maps. This will advance both the application and our basic understanding of objective acuity testing.With the overarching goal to substantially improve the robustness, reliability, and specificity of objective visual acuity estimates, the project has a strong focus on practical relevance, aiming at the translation of findings into clinical routine and the identification of biomarkers for therapy-success readout. Simultaneously, the experiments will shed light on important aspects of the structure-function interaction in the healthy and diseased human visual system.