Independent contributions of the orienting of attention, fixation offset and bilateral stimulation on human saccadic latencies
Independent contributions of the orienting of attention, fixation offset and bilateral stimulation on human saccadic latencies
复制标题
注意力定向、注视偏移和双边刺激对人类扫视潜伏期的独立贡献
作者：
R. Walker;Robert W. Kentridge;J. Findlay
In a series of experiments we examined the effects of the endogenous orienting of visual attention on human saccade latency. Three separate manipulations were performed: the orienting of visual attention, the prior offset of fixation (gap paradigm) and the bilateral presentation of saccade targets. Each of these manipulations was shown to make an independent contribution to saccade latency. In experiments 1 and 2 subjects were instructed to orient their attention covertly to a location by a verbal pre-cue; targets could appear in the attended hemifield (valid) or in the non-attended hemifield (invalid) together with a no-instruction (neutral) condition. Saccades were made under fixation gap and overlap conditions, to either single targets or two bilaterally presented targets which appeared at equal and opposite eccentricities in both hemifields. The results showed a large increase (cost) of saccade latency to invalid targets and a small non-significant decrease (benefit) of saccade latency to valid targets. The cost associated with invalid targets replicates the “meridian crossing effect” shown in manual reaction time experiments and is consistent with the hemifield inhibition and premotor models of attentional orienting. The use of a “gap” procedure produced a generalised facilitation of saccade latency, which was not modified by the prior orienting of visual attention. The magnitude of the gap effect was similar for saccades made to attended and non-attended stimulis. This suggests that the gap effect may be due to ocular motor disengagement, or a warning signal effect, rather than to the prior disengagement of visual attention. When two targets were presented simultaneously, one in each hemifield, saccade latency was slowed compared with the single target condition. The magnitude of this slowing was unaffected by the prior orienting of visual attention or by the fixation condition. The slowing was examined in more detail in experiment 3, by presenting targets with brief offset delays. The latency increase was maximal if the two targets were presented simultaneously and decreased if the distractor appeared at short intervals (20–80 ms) before or after the saccade target onset. If the non-attended stimulus was presented at greater intervals (160, 240 ms) before the saccade target, then a facilitation effect was observed. This demonstrates that the onset of a distractor in the non-attended hemifield can have both an inhibitory and a facilitatory effect on a saccade production.
猴子顶枕皮质损伤后视觉注意力和眼球扫视运动的缺陷。
影响因子：
2.5
作者：
Lynch,JC;McLaren,JW
通讯作者：
McLaren,JW
DOI：
--
发表时间：
1989
期刊：
Reviews of oculomotor research
影响因子：
--
作者：
D. Sparks;R. Hartwich-Young
通讯作者：
D. Sparks;R. Hartwich-Young
影响因子：
2.5
作者：
SCHILLER, PH;SANDELL, JH;MAUNSELL, JHR
通讯作者：
MAUNSELL, JHR