The effects of stimulus rotation and familiarity in visual search

Rauschenberger and Yantis (2006) observed that an intersecting circle-line combination enjoyed significantly greater search efficiency when it was oriented to resemble a "Q" than when it was oriented so that the intersecting line was vertical (cf. Treisman and Souther, 1985). Although a control experiment made it unlikely that the obliqueness of the line was responsible for the observed benefit, there was no direct evidence that this benefit was attributable to the "Q-ness" of the stimulus. In the present study, a subset of Rauschenberger and Yantis's experiments was repeated with Chinese subjects, who had never been exposed to the Latin alphabet. For these subjects, there was no benefit for the"Q"-like stimulus, in contrast to the results of Rauschenberger and Yantis's study. These results show that a simple 45 degrees rotation of a stimulus can affect search efficiency significantly--but only when this rotation bestows meaning, or familiarity, to that stimulus.     

The hard-won benefits of familiarity in visual search: naturally familiar brand logos are found faster

Familiar items are found faster than unfamiliar ones in visual search tasks. This effect has important implications for cognitive theory, because it may reveal how mental representations of commonly encountered items are changed by experience to optimize performance. It remains unknown, however, whether everyday items with moderate levels of exposure would show benefits in visual search, and if so, what kind of experience would be required to produce them. Here, we tested whether familiar product logos were searched for faster than unfamiliar ones, and also familiarized subjects with previously unfamiliar logos. Subjects searched for preexperimentally familiar and unfamiliar logos, half of which were familiarized in the laboratory, amongst other, unfamiliar distractor logos. In three experiments, we used an N-back-like familiarization task, and in four others we used a task that asked detailed questions about the perceptual aspects of the logos. The number of familiarization exposures ranged from 30 to 84 per logo across experiments, with two experiments involving across-day familiarization. Preexperimentally familiar target logos were searched for faster than were unfamiliar, nonfamiliarized logos, by 8 % on average. This difference was reliable in all seven experiments. However, familiarization had little or no effect on search speeds; its average effect was to improve search times by 0.7 %, and its effect was significant in only one of the seven experiments. If priming, mere exposure, episodic memory, or relatively modest familiarity were responsible for familiarity’s effects on search, then performance should have improved following familiarization. Our results suggest that the search-related advantage of familiar logos does not develop easily or rapidly.     

Acoustic factors in visual search

Previous work has shown that in searching for existing or absent “e.s” in printed prose, the presence or absence of silent “e.s” was less likely to be detected than that of pronounced “e.s.” It was suggested that the acoustic or kinaesthetic “image” was searched for evidence of an “e” in addition to the visual stimulus and that evidence from both sources was considered in making the appropriate response.

The present experiment employs mainly substitutive errors within words, which may or may not change their pronunciation. The results suggest that the form of the acoustic correlates has no bearing upon whether the words are detected as wrongly spelt, but that the presence or absence of an acoustic event corresponding in time to the spatial location of the error is important.     

An informational analysis of a visual search task

An earlier paper examined a visual-search task that required a S to locate a two-digit symbol from an array of digits. The results were not subjected to a detailed theoretical analysis. The present paper suggests an information-theory analysis of the data and shows that all of the data can be reduced to a consistent format. It is also argued that such an analysis may prove fruitful in the investigation of search strategies.     

Asymmetries in visual search: An introduction

In visual search tasks, observers look for a target stimulus among distractor stimuli. A visual search asymmetry is said to occur when a search for stimulus A among stimulus B produces different results from a search for B among A. Anne Treisman made search asymmetries into an important tool in the study of visual attention. She argued that it was easier to find a target that was defined by the presence of a preattentive basic feature than to find a target defined by the absence of that feature. Four of the eight papers in this symposium inPerception & Psychophysics deal with the use of search asymmetries to identify stimulus attributes that behave as basic features in this context. Another two papers deal with the long-standing question of whether a novelty can be considered to be a basic feature. Asymmetries can also arise when one type of stimulus is easier to identify or classify than another. Levin and Angelone’s paper on visual search for faces of different races is an examination of an asymmetry of this variety. Finally, Previc and Naegele investigate an asymmetry based on the spatial location of the target. Taken as a whole, these papers illustrate the continuing value of the search asymmetry paradigm.     

Visual search by children: the effect of background variation and the use of visual cues

A visual search task was used to assess developmental changes in children's selective attention to specified portions of a visual display. Seven-, nine-, and twelve-year-olds searched for a target letter in matrices of letters, each of which was centered in a form. On each matrix the forms were uniform or they varied in color, shape or both color and shape. The children searched with either no cues or with color or shape cues that could be used to restrict and speed their search. In all conditions search speed increased with age. Comparisons among conditions revealed three different age trends. With no cues children of all ages were slowed comparably by variation in background forms. With color cues all children increased their search speeds relative to no-cue speeds, suggesting selective fixation, but the 12-year-olds benefited most from the cues. With shape cues the search speed of 9- and 12-year-olds was slowed while that of 7-year-olds was either unchanged or was slowed only slightly. These different trends caution against overly general statements of changes with age in selective attention, and highlight the need to consider both particular task requirements and the processes used by subjects of different ages in tasks requiring selective attention.     

The influence of stimulus incongruity on the familiarity effect in visual selection

A consistent finding in the literature concerning visual selection is that a stimulus exposed to S subsequently loses some of its potential to elicit looking responses. Studies examining the familiarity effect in visual selection have not systematically examined the influence on that effect of various stimulus characteristics possessed by the familiarized stimulus. The present experiments examined the relationship between the magnitude of the familiarity effect and the level of incongruity represented by the familiarized stimulus and found it to be increasing and monotonie. In addition, Experiment 3 examined the generality of reports that familiarized stimuli are “liked” less than their unfamiliarized counterparts. The ease of explaining the results of the experiments using an “affect change” model of the familiarity effect and an “inforjnation-conflict resolution” model of that effect are discussed.     

Distractor familiarity leads to more efficient visual search for complex stimuli

Previous reports suggest that distractor familiarity plays an important role in determining visual search efficiency. However, the specific tasks used in those studies limit the extension of their findings to real-world situations and everyday images. In the present study, subjects engaged in a prolonged period of search experience as a control of their level of familiarity with a large set of target and distractor images. Reaction times and search slopes decreased dramatically over this period, especially for trials with a large target eccentricity and many distractors. Following extended practice, search among familiar distractors was more efficient than search among unfamiliar distractors. Furthermore, we found that familiar targets were located more efficiently than unfamiliar targets and that subjects were faster at locating targets that they had experienced in the majority of the search trials. These results show that prolonged visual experience facilitates processing of both target and distractor items during search.     

Mechanism underlying the self-enhancement effect of voice attractiveness evaluation: self-positivity bias and familiarity effect

The aim of the present study was to determine whether the self-enhancement effect of voice attractiveness evaluation is due to general self-positivity bias and/or the familiarity effect. The participants were asked to rate the attractiveness of their own voice, a friend's voice and strangers' voices. In addition, a self-reference valence (SR-valence) task was adopted in the experiment. Significant self-enhancement effects in voice attractiveness ratings were demonstrated, regardless of whether the participants recognized their self-voice or not. However, the friend-enhancement effect was found in only those participants who successfully recognized their friend's voice. Moreover, a significant correlation was found between self-positivity bias in the SR-valence task and the self-enhancement effect (but not the friend-enhancement effect). Our findings suggest that both the familiarity effect and self-positivity bias account for the vocal self-enhancement effect, and the influence of self-positivity bias could be implicit. The present study thus provides empirical evidence to clarify the potential explanations for the self-enhancement of voice attractiveness assessment.     

The effect of set on categorization in visual search

Two experiments examine whether set for a categorial difference or set for a target category is necessary in order to obtain the category effect in visual search. Eliminating a set for categorial difference does not diminish the size of the effect. When subjects are prevented from developing a useful set for the target category, however, the category effect is eliminated.     

The effect of geographic indication in advertising background pictures on product evaluation: The moderating role of familiarity

This study investigates whether geographic indications in the backgrounds of advertising pictures might affect the viewer's evaluation of a product. The findings reveal that participants in the proximal geographic indication evaluated the product more favourably than those in the distal geographic indication when they were exposed to feasibility‐related information. By contrast, participants in the distal geographic indication evaluated the product more favourably than those in the proximal geographic indication when they were exposed to desirability‐related information. However, familiarity with geographic indications eliminated this effect.     

The effect of visualization on visual search performance

Striking results recently demonstrated that visualizing search for a target can facilitate visual search for that target on subsequent trials (Reinhart et al. 2015). This visualization benefit was even greater than the benefit of actually repeating search for the target. We registered a close replication and generalization of the original experiment. Our results show clear benefits of repeatedly searching for the same target, but we found no benefit associated with visualization. The difficulty of the search task and the ability to monitor compliance with instructions to visualize are both possible explanations for the failure to replicate, and both should be carefully considered in future research exploring this interesting phenomenon.     

Age-related differences in the use of background layout in visual search

The effect of background layout on visual search performance, and more specifically on the tendency to refixate previously inspected locations and objects, was investigated. Older and younger adults performed a search task in which a background layout or landmark was present or absent in a gaze contingent visual search paradigm. Regardless of age, participants demonstrated fewer refixations when landmarks were present, with older adults showing a larger landmark advantage. This visual search advantage did not come at the cost of saccadic latency. Furthermore, the visual search performance advantage obtained in the presence of a background layout or landmark was observed both for individuals with small and large memory spans.     

Memory search and visual spatial attention: An event-related brain potential analysis

Event-related brain potentials (ERPs) were recorded from subjects as they attended to one diagonal of a visual display. The task was to respond only to memory set items (targets) at the attended diagonal and to ignore stimuli at the other diagonal. The probability that the display contained either an attended or an unattended target was 0.30. The spatial separation between attended and unattended stimuli was 1.6°. The ERP elicited by stimuli at the unattended diagonal contained a sequence of phasic components. The early N₁₇₀ and P₂₅₀ components were elicited by the onset of the display and the later components N₄₈₀ and P₅₅₀ by the offset of the display. The presence of masks delayed N₁₇₀ and P₂₅₀. The ERPs elicited by attended non-targets, in addition, contained an increased N₃₅₀ (C_z, F_z) and P₄₁₀ (P_3a, P_z, C_z). The ERPs elicited by attended and unattended non-targets started to differ after 200 msec. This finding suggested that selection is relatively late if selection must be based on a conjunction of features (location and orientation) and if the spatial separation between attended and unattended stimuli is small. Memory-set size affected the ERPs after 250 msec. The ERPs elicited by attended stimuli contained a broadly distributed (F_z, C_z, P_z) negative endogeneous component. The amplitude of this component was related to memory-set size. Finally, the ERPs elicited by attended targets contained a large P_3b (P_z, O_z) with a peak latency around 600 msec. The ERP results suggested the existence of three processing stages: (1) orienting to the attended stimuli; (2) controlled search, and (3) target decision.     

Driving forces in free visual search: An ethology

Visual search typically involves sequences of eye movements under the constraints of a specific scene and specific goals. Visual search has been used as an experimental paradigm to study the interplay of scene salience and top-down goals, as well as various aspects of vision, attention, and memory, usually by introducing a secondary task or by controlling and manipulating the search environment. An ethology is a study of an animal in its natural environment, and here we examine the fixation patterns of the human animal searching a series of challenging illustrated scenes that are well-known in popular culture. The search was free of secondary tasks, probes, and other distractions. Our goal was to describe saccadic behavior, including patterns of fixation duration, saccade amplitude, and angular direction. In particular, we employed both new and established techniques for identifying top-down strategies, any influences of bottom-up image salience, and the midlevel attentional effects of saccadic momentum and inhibition of return. The visual search dynamics that we observed and quantified demonstrate that saccades are not independently generated and incorporate distinct influences from strategy, salience, and attention. Sequential dependencies consistent with inhibition of return also emerged from our analyses.