Effects of covert attention on early vision

描述(申请人提供)：注意力如何影响知觉？这项研究的长期目标是通过研究内隐注意对早期视觉的影响，借鉴知觉、认知和神经生理学的理论工作，并使用视觉心理物理学的方法来促进对视觉注意的理解。有两种隐性注意系统：“暂时性”(外源性或刺激性)和“持续性”(内源性或概念驱动型)。最近的研究表明，短暂性注意通过增强对比敏感度、提高空间分辨率和加速信息积累来影响早期视觉。到目前为止，关于持续注意力的研究主要集中在高级认知过程上，而对其对早期视觉的影响知之甚少。这项拟议的研究将系统地研究这两种注意系统对早期视觉的影响。研究表明，瞬间的注意力是自动的，可能会导致表现受损或偏离我们的真实感知。当前建议的一个主要目标是检验这一假设，即持续注意比瞬时注意更灵活，因此可能更好地适应任务要求。研究的具体目的是：(1)通过评估注意和无注意位置的信号质量，考察注意对对比敏感度影响的时间进程，探索注意和选择性适应的获得机制如何影响刺激加工；(2)瞬时和持续注意对有注意和无注意位置的空间分辨率的影响，以及注意是否通过增加对高频的敏感度来影响通道的空间频率调谐；(3)瞬时和持续注意是否对一阶和二阶空间频率通道的增益和调谐产生不同影响；(4)通过研究双眼竞争研究瞬时注意和持续注意对对比敏感度和空间分辨率的影响水平；(5)标准双眼观看和双眼竞争时内隐注意对表观对比度和空间分辨率的影响。结果将在线性和非线性区域中运行的空间过滤器集合的理论框架内进行解释。这些发现对人为因素以及我们对许多神经心理疾病的理解都有影响，例如单边忽视、精神分裂症和ADHD。

DESCRIPTION (provided by applicant): How does attention affect perception? The long-term objective of the research is to contribute to the understanding of visual attention by studying the effects of covert attention on early vision, drawing on theoretical work in perception, cognition, and neurophysiology, and using methods from visual psychophysics. There are two systems of covert attention: 'transient' (exogenous or stimulus-driven) and 'sustained' (endogenous or conceptually-driven). Recent research has shown that transient attention affects early vision by enhancing contrast sensitivity, increasing spatial resolution, and accelerating information accrual. To date, studies on sustained attention have focused on higher cognitive processes, whereas relatively little is known about its effects on early vision. The proposed research will systematically investigate the effects of both attentional systems on early vision. Research has shown that transient attention, being automatic, may result in impaired performance or deviate us from veridical perception. A main objective of the current proposal is to test the hypothesis that sustained attention is more flexible and hence may adapt to task demands better than transient attention. The specific aims are to investigate: (1) the effects of transient and sustained attention on contrast sensitivity by evaluating the quality of the signal at both the attended and unattended locations across the visual field, examining the time course of attentional effects on contrast sensitivity, and exploring how the gain mechanisms of attention and selective adaptation affect stimulus processing; (2) the effects of transient and sustained attention on spatial resolution at the attended and unattended locations and whether attention affects the channels' spatial frequency tuning by increasing sensitivity to higher frequencies; (3) whether transient and sustained attention differentially affect the gain and tuning of 1st and 2nd order spatial frequency channels; (4) the levels at which transient and sustained attention exert their effects on contrast sensitivity and spatial resolution by studying binocular rivalry; (5) the effects of covert attention on apparent contrast and spatial resolution during standard binocular viewing and binocular rivalry. Results will be interpreted within the theoretical framework of an ensemble of spatial filters operating in linear and nonlinear regimes. The findings have implications for human factors, as well as for our understanding of many neuropsychological conditions, e.g. unilateral neglect, schizophrenia, and ADHD.