Early visual tagging: Effects of target-distractor similarity and old age on search, subitization, and counting.

Three experiments examined the effects of target-distractor (T-D) similarity and old age on the efficiency of searching for single targets and enumerating multiple targets. Experiment 1 showed that increasing T-D similarity selectively reduced the efficiency of enumerating small (     

Attentional capture by a salient distractor in visual search: The effect of target-distractor similarity.

Models of attentional selection are based on either stimulus-driven or goal-directed processes. Support for the latter comes from a study showing that a salient singleton in a search display can be ignored when the target has a different defining feature (Kumada, 1999). We show that this finding holds only when the target and the nonsalient distractors are highly dissimilar from one another. When the target and the distractors are made more similar, whilst ensuring that the target still pops out of the display, the salient distractor can no longer be ignored. This outcome is consistent with predictions from stimulus-driven accounts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the speed of pop-out in feature search.

When something unique is present in a scene, this element may become immediately visible and one has the impression that it pops out from the scene. This phenomenon, known as pop-out in the visual search literature, is thought to produce the fastest search possible, and response times for the detection of the pop-out target do not vary as a function of the number of nontargets. In this study, we challenge this notion and show that the detection of a given visual feature is faster for multiple targets than for a single pop-out target. However, when the task requires a detailed target analysis, the pop-out condition can be faster than the multiple-target condition. Current models of visual search are discussed in light of the findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Components of the location probability effect in visual search tasks.

In visual search tasks, targets are detected more rapidly when they appear in locations that commonly contain a target than when they appear in locations that rarely contain a target. Five experiments were conducted to investigate 2 specific properties of this location probability effect. In Exp I spatial location of a stimulus row was varied to determine whether high location probability facilitates target detection in a particular location in visual space or a particular relative position within the row. Both were facilitated to approximately the same extent. In Exp II an inducing target occurred with high probability in 1 of 4 display locations, and a test target occurred with equal probability in all 4 locations. Both targets were found more quickly in the high-probability location than in the other locations, but the advantage associated with targets in the high-probability location was larger for the inducing target than for the test target. In Exps III–V the correspondence between the components observed in Exps I and II was examined. The overall pattern of results was compatible with a model in which the location probability effect is produced partly by an attentional spotlight, which facilitates processing of any stimulus appearing in a particular location in visual space, and partly by a network of position-specific letter detectors, which facilitates detection of a particular letter in a particular relative position within a display. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of probability mode on preference reversal.

Estimated verbally and numerically the chances that specific events will occur using 6 analysts. 60 decision makers used each type of estimate to make binary-choice decisions and to bid for lotteries based on the events. The usual reversal of preference between choice and bidding procedures was found in the numerical condition, but the frequency of preference reversals was significantly reduced in the verbal condition. This reduction occurred because risk aversion was reduced in choice when verbal estimates were given, whereas bidding was unaffected by presentation mode. The pattern of results was predicted by and supports the hypothesis that the relative importance given to the dimensions of a prospect depends on the form in which the information is displayed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of the self-directed search on high school students.

Compared the effects on 959 high school students of the Self-Directed Search (SDS), a self-administered vocational counseling simulation; the Vocational Preference Inventory (VPI); and no treatment. Students taking the SDS or the VPI evaluated the instruments as moderately positive, reported feeling more satisfied with their current occupational choice, and were considering more occupational alternatives than the control group both the day after the experiment and 3 wks later. Students taking the SDS selected occupations most consistent with their personality traits and reported less need to see a counselor immediately. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of serial rehearsal training on memory search.

Examined the effects of storage processing on short-term memory search. 32 moderate and 32 high IQ 4th-5th graders were given an S. Sternberg (1966, 1969) recognition memory task. Half of the Ss were trained to use a serial rehearsal strategy during target set storage, and half were given no specific strategy training. The training variable was crossed with rehearsal requirement (overt or covert) so that storage processing could be monitored directly. Dependent measures included S-paced study times, overt rehearsals, and reaction times. Results indicate IQ-related differences in the rate of memory search in the absence of differences in rehearsal during storage. In addition, serial rehearsal training facilitated memory search when rehearsal was covert, particularly for high IQ Ss. The data are discussed with regard to target set storage resulting from a serial rehearsal pattern and to the apparent inverse relationship between IQ and memory-search rate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Target location probability effects in visual search: An effect of sequential dependencies.

Target location probability was manipulated in a visual search task. When the target was twice as likely to appear on 1 side of the display as the other, manual button-press response times were faster (Experiment 1A) and first saccades were more frequently directed (Experiment 1B) to the more probable locations. When the target appeared with equal probability at each location in this search task, performance benefited from repetition of target location in the preceding trials (Experiment 2). When the trial sequence was constrained so that target location did not repeat within a series of 4 trials, there was no longer an advantage for more probable locations (Experiment 3). The authors conclude that the search benefits for more probable locations resulted from short-term target location repetitions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Asymmetry in visual search for targets defined by differences in movement speed.

Perception of motion speed was investigated with the visual search paradigm, using human Ss. When searching for a fast target among slow distractors, reaction time (RT) was minimally affected as the number of distractors was increased. In contrast, RT to detect a slow target among fast distractors was slow and linearly related to the number of distractors. The effect cannot be attributed to differences in temporal frequency, discriminability, or one type of representation that might result from spatiotemporal filtering. An alternative hypothesis that can account for the asymmetry is that speed detectors operate as high-pass filters in the velocity domain. This hypothesis is in agreement with results obtained in psychophysical studies on motion adaptation as well as data from single-cell recordings in nonhuman species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of lithium carbonate on the memory and motor speed of bipolar outpatients.

We examined the effect of lithium on the memory and motor speed of 22 outpatients with affective disorders in remission. Patients were assessed weekly over a 5-week period starting at their current lithium dosage, twice during administration of a blind placebo, and twice after their lithium was blindly reinstated. Motor speed was assessed using the finger tapping test. Memory was assessed using the Buschke selective reminding protocol. Mood was assessed at each session to ensure remitted status by clinical interview, the Hamilton Rating Scale for Depression, the Longitudinal Rating of Manic States Scale, and a subjective state questionnaire. Weekly blood samples were also drawn to assess plasma lithium level by means of atomic absorption spectrophotometry. The results indicated that lithium had significant detrimental effect on memory and motor speed: Performance improved when lithium was discontinued and declined when lithium was reintroduced. The implications for patient management and diagnosis in bipolar disorder are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of implementation intentions on the self-reported frequency of drivers' compliance with speed limits.

This study tested the efficacy of implementation intentions in the context of drivers' speeding behavior. Participants (N = 300) completed self-report measures of goal intention and behavior, and they were randomly assigned to an experimental condition, which required them to specify an implementation intention, or a control condition. One month postbaseline, self-reported compliance with speed limits significantly increased for experimental participants but not for control participants. The effects of specifying an implementation intention on behavior increased with the strength of drivers' goal intentions. Finally, analysis of participants' implementation intentions revealed that specifying more behavioral strategies increased the frequency with which participants reported complying with the speed limit. Implications of the findings are discussed in relation to enhancing road safety interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Judgments of speed on the open highway.

"Male adult drivers, while decelerating on the open highway, were required to make judgments about the speed of the passenger car… varying amounts of exposure to a constant speed of 35 or 50 mph." Speed judgments were found to be reliable, but independent of influence from varying amounts of exposure on these speed judgments (speed adaptation). Suggestions are made as to why the procedure might have obscured the presence of adaptation effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of life and job stress on information search behaviors of organizational members.

Examined the relationship of stressful life events in and out of work to role-relevant information search. It was suggested that stressful life events lead a person to question the appropriateness of typical modes of role enactment resulting in increased role-relevant information search. 44 adults (mean age 37.7 yrs) employed in a wide variety of organizations completed the Social Readjustment Rating Scale and the Organizational Readjustment Rating Scale that measure 2 types of stressful events (life and work), and role-related information search was assessed in 2 settings (on and off the job). Results show that stressful events significantly predicted information search activities. However, work-related stressful events predicted information search conducted on the job, whereas life stress predicted off-the-job search. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

不同弹性模量的基台-种植体组合对周围成骨性能的影响

利用有限元分析软件计算了不同静力作用下的多种基台-种植体周围骨组织的应力分布.模拟结果显示, 基台-种植体组合中Ti6Al4V钛合金-聚醚醚酮(TC4-PEEK)相对于其他实验组其应力集中程度现象可以有效降低, 周围骨组织的应力分布较为均匀, 最大应力值为40~60 MPa.在轴向加载条件下, 不同基台-种植体系统中PEEK种植体的应力水平较小, 而周围骨组织应力水平较大; 在斜向45°加载条件下, 相对于其他两种基台-种植体系统, TC4-PEEK的应力水平更低, 其周围骨组织中的皮质骨承受的最大应力值为55 MPa, 松质骨承受的最大应力值为5 MPa, 综合来看的应力水平最小, 有助于骨沉积和成骨量增加, 从而有效提高种植体的界面稳定性.      

不同弹性模量的基台--种植体组合对周围成骨性能的影响

利用有限元分析软件计算了不同静力作用下的多种基台-种植体周围骨组织的应力分布.模拟结果显示,基台-种植体组合中Ti6Al4V钛合金-聚醚醚酮(TC4-PEEK)相对于其他实验组其应力集中程度现象可以有效降低,周围骨组织的应力分布较为均匀,最大应力值为40～60 MPa.在轴向加载条件下,不同基台-种植体系统中PEEK种植体的应力水平较小,而周围骨组织应力水平较大;在斜向45°加载条件下,相对于其他两种基台-种植体系统,TC4-PEEK的应力水平更低,其周围骨组织中的皮质骨承受的最大应力值为55 MPa,松质骨承受的最大应力值为5 MPa,综合来看的应力水平最小,有助于骨沉积和成骨量增加,从而有效提高种植体的界面稳定性.     

Effects of stimulus–response probability on choice reaction time: Evidence from the lateralized readiness potential.

The lateralized readiness potential (LRP) was measured in 2-choice reaction time (RT) tasks with unequally probable stimuli and responses. Responses were faster and more accurate in high- than in low-probability trials. LRPs indicated that participants prepared the high-probability response and suggested that this preparation speeded high-probability responses relative to low-probability responses. When stimulus onset was temporally predictable, the high-probability response was clearly prepared prior to stimulus onset. When stimulus onset was unpredictable, preparation of the high-probability response occurred just after stimulus onset, even on low-probability trials where this preparation was inappropriate. With unpredictable stimulus onsets, RT distributions were adequately represented by a mixture model with prepared versus unprepared states; with predictable onsets, they were not. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A note on superadditive probability judgment.

Recent studies have demonstrated subadditivity of human probability judgment: The judged probabilities for an event partition sum to more than 1. We report conditions under which people's probability judgments are superadditive instead: The component judgments for a partition sum to less than 1. Both directions of deviation from additivity are interpreted in a common framework, in which probability judgments are often mediated by judgments of evidence. The 2 kinds of nonadditivity result from differences in recruitment of supporting evidence together with reduced processing of nonfocal propositions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Effects of target value and exposure duration on recall in a visual search task.

Investigated the effects of exposure duration (.5, .75, 1.0, 2.0, and 3.0 sec/slide) and ratio of value (16:1 and 2:1) on the recall of high- and low-value letters in a visual search task. Results with 80 male undergraduates indicate that although ss' strategies tended to favor reports of the high- over the low-value stimuli, differences in performance varied directly with both ratio and length of exposure. Results are discussed and related to the inconsistencies in previous findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

In search of the links.

Reviews the book, Cognition, metacognition, and reading by D. L. Forrest-Pressley and T. G. Waller (1984). In the introduction to this monograph the authors point out that, in spite of receiving much recent attention, metacognition is only vaguely defined in the literature, and its relationship to cognition and cognitive activities such as reading is particularly unclear. Further, they claim that the difficulties that researchers have encountered in understanding reading is attributable to their failure to understand properly the complexity of the reading process. The solution offered by the authors is to assign metacognition a central role in reading by defining the reading process as the interaction of at least three skills--decoding, comprehension, and mature reading strategies--each of which has a cognitive and metacognitive component. The potential contribution of this volume depends upon the extent to which this approach succeeds in clarifying the concept of metacognition and advancing our understanding of the cognitive basis of reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved)