Visual Search Asymmetry Due to the Relative Magnitude Represented by Number Symbols

In visual search tasks, physically large target stimuli are more easily identified among small distractors than are small targets among large distractors. The present study extends this finding by presenting preliminary evidence of a new search asymmetry: stimuli that symbolically represent larger magnitude are identified more easily among featurally equivalent distractors that represent smaller magnitude. Participants performed a visual search task using line-segment digits representing the numbers 2 and 5, and the numbers 6 and 9, as well as comparable non-numeric control stimuli. In three experiments, we found that search times are faster when the target is a digit that represents a larger magnitude than the distractor, although this pattern was not evident in one additional experiment. The results provide suggestive evidence that the magnitude of a number symbol can affect perceptual comparisons between number symbols, and that the semantic meaning of a target stimulus can systematically affect visual search.

Download Full-text

When visual search target is rare: overweighting or under weighting the probability?

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/1541931218621344 ◽

2018 ◽

Vol 62 (1) ◽

pp. 1520-1524

Author(s):

Hanshu Zhang ◽

Joseph W. Houpt

Keyword(s):

Visual Search ◽

Search Task ◽

Visual Search Task ◽

Response Times ◽

Threshold Model ◽

Decision Makers ◽

Target Presence ◽

Model Assumption ◽

Search Tasks ◽

Low Prevalence

The prevalence of items in visual search may have substantial performance consequences. In laboratory visual search tasks in which the target is rare, viewers are likely to miss the target. A dual-threshold model proposed by Wolfe and Van Wert (2010) assumes that in the low prevalence condition, viewers shift their criteria resulting in more miss errors. However, from the prospective of prospect theory (Kahneman & Tversky, 1979), decision makers tend to overweight small probability. To explore how viewers subjectively weight the probability in the low prevalence visual search task, we compared viewers’ criteria with the optimal criteria by presenting different probability descriptions for a fixed prevalence rate. The data from this experiment indicated that target presence had an effect on viewers’ accuracy and response times but not probability descriptions. Viewers’ criteria under different probability descriptions were higher than optimal. These results are in accordance with the dual-threshold model assumption that viewers respond “target absent” more frequently than optimal, leading to more miss errors in the low prevalence condition.

Download Full-text

Visual Search Performance by Paranoid and Chronic Undifferentiated Schizophrenics

Perceptual and Motor Skills ◽

10.2466/pms.1981.53.2.411 ◽

1981 ◽

Vol 53 (2) ◽

pp. 411-418

Author(s):

Lance A. Portnoff ◽

Jerome A. Yesavage ◽

Mary B. Acker

Keyword(s):

Differential Diagnosis ◽

Visual Search ◽

Cross Validation ◽

Search Task ◽

Visual Search Task ◽

Search Performance ◽

Attentional Deficits ◽

Search Tasks ◽

Chronic Schizophrenics ◽

Stimulus Mode

Disturbances in attention are among the most frequent cognitive abnormalities in schizophrenia. Recent research has suggested that some schizophrenics have difficulty with visual tracking, which is suggestive of attentional deficits. To investigate differential visual-search performance by schizophrenics, 15 chronic undifferentiated and 15 paranoid schizophrenics were compared with 15 normals on two tests measuring visual search in a systematic and an unsystematic stimulus mode. Chronic schizophrenics showed difficulty with both kinds of visual-search tasks. In contrast, paranoids had only a deficit in the systematic visual-search task. Their ability for visual search in an unsystematized stimulus array was equivalent to that of normals. Although replication and cross-validation is needed to confirm these findings, it appears that the two tests of visual search may provide a useful ancillary method for differential diagnosis between these two types of schizophrenia.

Download Full-text

Priming Race in Biracial Observers Affects Visual Search for Black and White Faces

Psychological Science ◽

10.1111/j.1467-9280.2006.01717.x ◽

2006 ◽

Vol 17 (5) ◽

pp. 387-392 ◽

Cited By ~ 48

Author(s):

Joan Y. Chiao ◽

Hannah E. Heck ◽

Ken Nakayama ◽

Nalini Ambady

Keyword(s):

Visual Search ◽

Racial Identity ◽

Search Task ◽

Visual Search Task ◽

Black Identity ◽

White Identity ◽

Top Down ◽

Search Asymmetry ◽

Black And White ◽

Black Faces

We examined whether or not priming racial identity would influence Black-White biracial individuals' ability to visually search for White and Black faces. Black, White, and biracial participants performed a visual search task in which the targets were Black or White faces. Before the task, the biracial participants were primed with either their Black or their White racial identity. All participant groups detected Black faces faster than White faces. Critically, the results also showed a racial-prime effect in biracial individuals: The magnitude of the search asymmetry was significantly different for those primed with their White identity and those primed with their Black identity. These findings suggest that top-down factors such as one's racial identity can influence mechanisms underlying the visual search for faces of different races.

Download Full-text