Covert attention regulates saccadic reaction time by routing between different visual-oculomotor pathways.
نویسندگان
چکیده
Covert attention modulates saccadic performance, e.g., the abrupt onset of a task-irrelevant visual stimulus grabs attention as measured by a decrease in saccadic reaction time (SRT). The attentional advantage bestowed by the task-irrelevant stimulus is short-lived: SRT is actually longer ~200 ms after the onset of a stimulus than it is when no stimulus appears, known as inhibition of return. The mechanism by which attention modulates saccadic reaction is not well-understood. Here, we propose two possible mechanisms: by selective routing of the visuomotor signal through different pathways (routing hypothesis) or by general modulation of the speed of visuomotor transformation (shifting hypothesis). To test them, we designed a cue gap paradigm in which a 100-ms gap was introduced between the fixation point disappearance and the target appearance to the conventional cued visual reaction time paradigm. The cue manipulated the location of covert attention, and the gap interval resulted in a bimodal distribution of SRT, with an early mode (express saccade) and a late mode (regular saccade). The routing hypothesis predicts changes in the proportion of express saccades vs. regular saccades, whereas the shifting hypothesis predicts a shift of SRT distribution. The addition of the cue had no effect on mean reaction time of express and regular saccades, but it changed the relative proportion of two modes. These results demonstrate that the covert attention modification of the mean SRT is largely attributed to selective routing between visuomotor pathways rather than general modulation of the speed of visuomotor transformation.
منابع مشابه
Title: Covert Attention Regulates Saccadic Reaction Time by Routing between Different Visual-oculomotor Pathways Running Head: Covert Attention Routes Visual-oculomotor Pathways Covert Attention Regulates Saccadic Reaction Time by Routing between Different Visual-oculomotor Pathways
Manuscript for Journal of Neurophysiology 1 Title: Covert Attention Regulates Saccadic Reaction Time by Routing between Different 2 Visual-oculomotor Pathways 3 Running head: Covert Attention Routes Visual-oculomotor Pathways 4 Authors: Shaobo Guan (关少波), Yu Liu (刘昱), Ruobing Xia(夏若冰), Mingsha Zhang (张鸣 5 沙) 6 Affiliation: 7 Institute of Neuroscience, Shanghai Institutes for Biologica...
متن کاملRouting between Different Visual-oculomotor Pathways Covert Attention Regulates Saccadic Reaction Time By
متن کامل
Counterproductive Effect of Saccadic Suppression during Attention Shifts
During saccadic eye movements, the processing of visual information is transiently interrupted by a mechanism known as "saccadic suppression" [1] that is thought to ensure perceptual stability [2]. If, as proposed in the premotor theory of attention [3], covert shifts of attention rely on sub-threshold recruitment of oculomotor circuits, then saccadic suppression should also occur during covert...
متن کاملVisuomotor Origins of Covert Spatial Attention
Covert spatial attention produces biases in perceptual performance and neural processing of behaviorally relevant stimuli in the absence of overt orienting movements. The neural mechanism that gives rise to these effects is poorly understood. This paper surveys past evidence of a relationship between oculomotor control and visual spatial attention and more recent evidence of a causal link betwe...
متن کاملVisual and oculomotor selection: links, causes and implications for spatial attention.
Natural scenes contain far more information than can be processed simultaneously. Thus, our visually guided behavior depends crucially on the capacity to attend to relevant stimuli. Past studies have provided compelling evidence of functional overlap of the neural mechanisms that control spatial attention and saccadic eye movements. Recent neurophysiological work demonstrates that the neural ci...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of neurophysiology
دوره 107 6 شماره
صفحات -
تاریخ انتشار 2012