Attentional requirements in a ‘preattentive’ feature search task

Julian S. Joseph; Marvin M. Chun; Ken Nakayama

doi:10.1038/42940

Human Frontal Eye Fields and Visual Search

Journal of Neurophysiology ◽

10.1152/jn.01086.2002 ◽

2003 ◽

Vol 89 (6) ◽

pp. 3340-3343 ◽

Cited By ~ 134

Author(s):

Neil G. Muggleton ◽

Chi-Hung Juan ◽

Alan Cowey ◽

Vincent Walsh

Keyword(s):

Visual Search ◽

Eye Movements ◽

False Alarm ◽

Eye Movement ◽

Magnetic Stimulation ◽

Search Task ◽

Scene Analysis ◽

Frontal Eye Fields ◽

Feature Search ◽

Search Tasks

Recent physiological recording studies in monkeys have suggested that the frontal eye fields (FEFs) are involved in visual scene analysis even when eye movement commands are not required. We examined this proposed function of the human frontal eye fields during performance of visual search tasks in which difficulty was matched and eye movements were neither necessary nor required. Magnetic stimulation over FEF modulated performance on a conjunction search task and a simple feature search task in which the target was unpredictable from trial to trial, primarily by increasing false alarm responses. Simple feature search with a predictable target was not affected. The results establish that human FEFs are critical to visual selection, regardless of the need to generate a saccade command.

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Far-space neglect in conjunction but not feature search following transcranial magnetic stimulation over right posterior parietal cortex

Journal of Neurophysiology ◽

10.1152/jn.00492.2013 ◽

2014 ◽

Vol 111 (4) ◽

pp. 705-714 ◽

Cited By ~ 5

Author(s):

Indra T. Mahayana ◽

Chia-Lun Liu ◽

Chi Fu Chang ◽

Daisy L. Hung ◽

Ovid J. L. Tzeng ◽

...

Keyword(s):

Visual Search ◽

Transcranial Magnetic Stimulation ◽

Parietal Cortex ◽

Magnetic Stimulation ◽

Posterior Parietal Cortex ◽

Search Task ◽

Association Cortex ◽

Feature Search ◽

Posterior Parietal

Near- and far-space coding in the human brain is a dynamic process. Areas in dorsal, as well as ventral visual association cortex, including right posterior parietal cortex (rPPC), right frontal eye field (rFEF), and right ventral occipital cortex (rVO), have been shown to be important in visuospatial processing, but the involvement of these areas when the information is in near or far space remains unclear. There is a need for investigations of these representations to help explain the pathophysiology of hemispatial neglect, and the role of near and far space is crucial to this. We used a conjunction visual search task using an elliptical array to investigate the effects of transcranial magnetic stimulation delivered over rFEF, rPPC, and rVO on the processing of targets in near and far space and at a range of horizontal eccentricities. As in previous studies, we found that rVO was involved in far-space search, and rFEF was involved regardless of the distance to the array. It was found that rPPC was involved in search only in far space, with a neglect-like effect when the target was located in the most eccentric locations. No effects were seen for any site for a feature search task. As the search arrays had higher predictability with respect to target location than is often the case, these data may form a basis for clarifying both the role of PPC in visual search and its contribution to neglect, as well as the importance of near and far space in these.

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Evidence for Attentional Capture by a Surprising Color Singleton in Visual Search

Psychological Science ◽

10.1111/1467-9280.00488 ◽

2002 ◽

Vol 13 (6) ◽

pp. 499-505 ◽

Cited By ~ 81

Author(s):

Gernot Horstmann

Keyword(s):

Visual Search ◽

Reaction Time ◽

Target Letter ◽

Attentional Capture ◽

Search Task ◽

Color Singleton ◽

Conjunction Search ◽

Feature Search ◽

Set Size ◽

And Performance

Three experiments were conducted to investigate whether surprising color singletons capture attention. Participants performed a visual search task in which a target letter had to be detected among distractor letters. Experiments 1 and 2 assessed accuracy as the dependent variable. In Experiment 1, the unannounced presentation of a color singleton 500 ms prior to the letters (and in the same position as the target letter) resulted in better performance than in the preceding conjunction search segment, in which no singleton was presented, and performance was as good in this surprise-singleton trial as in the following feature search segment, in which the singleton always coincided with the target. In contrast, no improvement was observed when the color singleton was presented simultaneously with the letters in Experiment 2, indicating that attentional capture occurred later in the surprise trial than in the feature search segment. In Experiment 3, set size was varied, and reaction time was the dependent variable. Reaction time depended on set size in the conjunction search segment, but not in the surprise trial nor in the feature search segment. The results of the three experiments support the view that surprising color singletons capture attention independently of a corresponding attentional set.

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