Pigeon same–different concept learning with multiple stimulus classes.

Two experiments examined the acquisition and transfer of a complex same–different discrimination by pigeons. With the use of a 2-alternative choice task, 5 pigeons were reinforced for discriminating odd-item Different displays, in which a contrasting target was present, from Same displays, in which all elements were identical. Four different types of same-different displays were concurrently tested. The display types differed in their configuration (texture vs. visual search organization), the nature of their elements (small and large colored shapes; pictures of birds, flowers, fish, and humans), and the processing demands required by their global-local element arrangement. Despite these differences, the pigeons learned to discriminate all 4 display types at the same rate and showed positive discrimination transfer to novel examples of each type, suggesting that a single generalized rule was used to discriminate all display types. These results provide some of the strongest evidence yet that pigeons, like many primates, can learn an abstract, visually mediated same-different concept. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex differences in monitoring performance.

220 male and 220 female undergraduates monitored a visual display for 1 hr. Although the results indicate females were poorer monitors, detecting 10% fewer signals and committing more false alarms, these sex differences accounted for only 4% of the variance of detection performance and less than 1% of the variance of the false alarm measure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Color coding effects in compatible and noncompatible display-control arrangements.

40 males viewed 4 arrangements of display-control panels with color coding or no color coding, and with displays and controls arranged in either a compatible or noncompatible arrangement. Ss' task was to shut off the display as fast as possible for 80 trials. Color coding was more effective when displays and controls were arranged in a noncompatible fashion, and had no effect when display and control were arranged in a compatible manner. The results support the importance of compatibility in display-control location. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of symmetry in the mirror-image confusions of preschoolers.

64 children between 3 and 5 yrs old were given a location copying task both with a standard and comparison display side by side (horizontally aligned) and with displays aligned along their diagonals. Displays were pegboards of 3 levels of complexity: 2-by-2, 4-by-4, and 6-by-6 holes. Left–right reversals were the predominant errors and were frequent for horizontally aligned displays; left–right reversals were less frequent and performance more accurate for diagonally aligned displays. Only for interior positions on the 6-by-6 hole array were errors other than left–right reversals frequent; and for these positions only, alignment did not influence accuracy. Results fail to support P. Bryant's (1973, 1974) hypothesis that mirror-image confusions are no more frequent than other in-line (in-row) errors and that these errors result from dependence on an in-line comparison strategy. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for directional scanning with the order-of-report factor excluded.

Conducted 2 experiments with 40 undergraduates to study directional-scanning in tachistoscopic recogniton, using a letter-detection procedure. Displays presented in normal orientation (Exp I) were processed left to right. The left-to-right processing reflected the order of scanning rather than simply the order of report, because the S had merely to report whether a particular letter was present or absent in the display, rather than report the entire display. When left-right mirror images were presented (Exp II), the direction of scanning changed towards right to left. Further, even with mirror reversals, performance was better on word displays than on nonword displays. (French summary) (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Missed targets are more frequent than false alarms: a model for error rates in visual search

In many visual search tasks, reaction times (RTs) for target detection are measured as a function of display size. The corresponding error rates are usually low but increase with increasing display size. Missed-target errors are more common than false alarms. In recent models of visual search, the error rates were attributed to a premature search termination and error rates increasing with display size were interpreted as indicating a speed-accuracy trade-off and an underestimation of search times per item (obtained from RT slopes). A model is described in which errors occur as a result of imperfect rather than incomplete search (i.e., it is assumed that there are task-specific probabilities of categorizing a target or a distractor incorrectly). Signal-detection theory is used to show that the observed error rate properties can be attributed to an optimized decision strategy. "Corrections" of RT data are thus questionable.     

Usefulness of preoperative location studies in the initial surgical intervention in primary hyperparathyroidism

BACKGROUND: The aim of the study was to assess whether preoperative localization is helpful in improving the outcome of initial surgery of primary hyperparathyroidism (PHPT). PATIENTS AND METHODS: Retrospective review of 100 patients treated surgically for PHPT. In 30 cases (group I) 3 or 4 localization studies were performed from the following: ultrasonography (US), computed tomography (CT), thallium-technetium substraction scintigraphy (TTS), and technetium 99m-sestamibi scanning (MIBI). Thirty one patients (group II) were operated without previous localization. Sensitivity and false localization rate of image studies were calculated, and cure and surgical complication rates were compared in both groups. RESULTS: Both groups were similar in mean age (56.2 vs 52.2 years), serum calcium (12.3 vs 12.1 mg/dl), intact PTH levels (304 vs 254 pg/ml), pathology (26 adenomas, 3 hyperplasias and 1 carcinoma vs 27 adenomas, 3 hyperplasias and 1 carcinoma) and additional clinical and biochemical data. The highest sensitivity technique was for MIBI (62.5%). The highest false localization rate was for CT (27.6%). No significative differences were found between groups I and II for the cure rate (90% vs 87.1%) or surgical complications (3.3% vs 3.2%). CONCLUSIONS: In our series of patients with primary hyperparathyroidism preoperative localization studies display low sensitivity and estimable false localization rate. These techniques increment cost and don't improve success rate of initial surgery in PHPT. Therefore, we believe its performance controversial.     

Speed and accuracy of scale reading as a function of the number of reference markers.

The speed and accuracy of determining target position on a polar coordinate display as a function of the number of scale rings were investigated for displays ranging in diameter from 5 to 11 inches, with 1, 3, 5, 10, 20, or 40 scale rings. "Error of interpolation (in percentage of the total range of the display) decreased as a function of the number of scale rings used. The frequency of gross errors (misidentification of scale rings) and the time required to make readings increased as a function of the number of scale rings. Increasing display size improved interpolation accuracy slightly and decreased the frequency of gross errors markedly. Constant errors of interpolation were found to be a function of the position of the target between scale rings and also a function of the number of scale rings used." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Color versus shape coding in information displays.

8 Ss counted objects of a specified color or shape on displays of 20, 60, or 100 items. Counting time and errors increased with increasing display density. Counting based on a 5-valued color code was faster and more accurate than counting using any of 3 shape codes. Color counting was not affected by the particular shape code on which the colors were superimposed. Shape counting was somewhat faster and/or more accurate when color did not vary on the display, and vice versa. Differences in counting performance appeared among the 3 shape codes and among certain of the symbols within shape codes, and small differences were confirmed among the particular code colors used. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of alternative modeling strategies on outcomes of interpersonal-skills training.

The effects of 2 alternative modeling strategies (using multiple scenarios and combining negative and positive model displays) on outcomes of a behavior modeling training program were explored. Trainees (N?=?72) participated in a program on assertive communication structured to allow for a controlled experimental design that crossed scenario variability (1 vs multiple scenarios) with model display variability (positive model displays vs positive and negative model displays). Outcomes assessed included trainee reactions, learning, and retention and behavioral measures of reproduction and generalization. The effects of multiple scenarios were negligible, but the positive and negative combination of model displays had a significant positive effect on trainee generalization and a significant negative effect on reproduction. Implications for future modeling research and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exploring the Boundary Conditions of the Delay Hypothesis With Adjunct Displays.

Previously, D. H. Robinson and G. Schraw (see record 1995-11458-001) found that advantages of graphic organizers (GOs) over outlines disappeared when testing was delayed. However, D. H. Robinson and K. A. Kiewra (see record 1996-12932-001), using a longer text and several displays, found that delayed testing was detrimental for outlines. In 2 experiments, the authors explored the boundary conditions of the delay hypothesis (T. Andre; see record 1990-20995-001) with adjunct displays. In Experiment 1, the authors replicated the findings of Robinson and Schraw using a longer text (1,000 vs. 200 words) and a shorter delay (5 vs. 25 min). In Experiment 2. the authors replicated the findings of Robinson and Kiewra using a 6.500-word text with multiple displays and a shorter delay (5 min vs. 1 days). With short text and 1 display, outlines may encourage more distinctive encoding (L. L. Jacoby. F. I. M. Craik, & I. Begg; see record 1981-00462-001) because of computational inefficiency. However, with long text and several displays, computationally efficient GOs may allow for optimal decision difficulty. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of error density and set in a vigilance task.

To study ability to detect certain signals while persistently looking for them, 216 students were involved in proofreading tasks. Results were sought pertaining to error detection as a function of error density, false detections at various error levels, influence of previous density on present detection, and false detections after shifts in error density. All vigilance tasks may be subject to decreasing efficiency at extremely high error levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Color coding and visual separability in information displays.

12 experimental Ss performed both visual search and class counting tasks, viewing displays containing 20, 60, or 100 items. Each item consisted of a vector, letter, and 3-digit number grouped together, and was presented as white-on-black in some displays, or in 1 of 5 colors. The color code was redundant with the 5 class-designator letters that were used. Average search and counting time, and counting errors, increased with increasing display density (number of items). None of these measures varied significantly among the 5 different target classes (colors). Addition of the redundant color code resulted in an average time reduction of 65% in the visual search task and 69% in the counting task, with a reduction of 76% in errors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reducing the performance-cue bias in work behavior ratings: Can groups help?

The authors examined whether the performance-cue bias can be reduced by relying on groups as raters. Study participants (N = 333) were provided with feedback regarding the performance of a workgroup and, after observing the group, assigned to an individual or group rater condition to complete a behavioral rating instrument. Results revealed that when provided with positive (vs. negative) feedback, individuals attributed more effective and fewer ineffective behaviors to the workgroup; however, group ratings were unaffected by the feedback. In addition, feedback biased the decision criteria and false alarm rates of individuals but not of groups. Discussion of when groups may attenuate versus amplify bias in performance appraisal judgments emphasizes 2 key elements--bias magnitude and task perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Estimating ancestral states of a communicative display: a comparative study of Cyclura rock iguanas

In this study we describe the signature headbob displays of seven of the eight extant species of Cyclura iguanas using data collected from the field and from captive animals. We used phylogenetic comparative methods to estimate the ancestral states of several measures of the headbob displays, including number of headbobs and the duration of headbobs and inter-bob pauses. Divergence in the headbob display among species has been substantial, with some major changes occurring within only a few (about six) generations. Otherwise, results are consistent with those obtained previously for other lizards which suggest that there is an evolutionary limit on the total duration of headbob displays. Differences in the results obtained using different phylogenetic methods suggest that although estimates of ancestral states are reasonably robust to violations of evolutionary assumptions, we cannot determine the standard errors of those ancestral phenotypes accurately without more detailed information about the types of forces (e.g. selection, drift) underlying evolutionary change in these traits. In particular, within-species variation had a substantial impact on the standard errors of estimated ancestral states, and should be included in such estimations whenever possible. Finally, our results emphasize the importance of conserving behavioural as well as genetic diversity in trying to preserve endangered species for possible reintroduction into the wild. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.     

Age-related decline of visual processing components in change detection.

Previous research has suggested that an age-related decline in change detection may be due to older adults using a more conservative response criterion. However, this finding may reflect methodological limitations of the traditional change detection design, in which displays are presented continuously until a change is detected. Across 2 experiments, the authors assessed adult age differences in a version of change detection that required a response after each pair of pre- and postchange displays, thus reducing the potential contribution of response criterion. Older adults performed worse than younger adults, committing more errors and requiring a greater number of display cycles for correct detection. These age-related performance declines were substantially reduced after controlling statistically for elementary perceptual speed. Search strategy was largely similar for the 2 age groups, but perceptual speed was less successful in accounting for age-related variance in detectability when a more precise spatial localization of change was required (Experiment 2). Thus, the negative effect of aging in the present tasks lies in a reduction of detection efficiency due largely to processing speed, though some strategy-level effects may also contribute. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Illusory words: The roles of attention and of top–down constraints in conjoining letters to form words.

Conducted 3 experiments with 40 undergraduates to confirm that illusory recombinations of letters can be seen when several words or letter-strings are presented too briefly to allow focused attention to each item in turn and to explore the role of lexical entries in promoting or preventing these preceptual errors. Overall findings indicate that when attention was divided among 4 briefly exposed syllables, Ss mistakenly detected targets whose letters were present in the display but in the wrong combinations. These illusory conjunctions were somewhat more frequent when the target was a word and when the distractors were nonwords, but the effects of lexical status were small and did not reach significance in free report of the same displays. Search performance was further impaired if the nonwords were unpronouncable consonant strings rather than increased conjunction errors. Results are discussed in relation to feature-integration theory and to current models of word perception. (46 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spatial factors in check reading of dial groups.

"Observers were required to detect deviant pointers within a display panel of 16 circular dials… the spatial locations of the deviant pointers within a panel were controlled in such a way that it was possible to determine the percentage of deviations detected as a function of quadrant location and position within quadrants. The consistency of these spatial effects was determined over 3 durations of panel exposure. The results showed that spatial location was an important determinant of the number of detections that were made. The pattern of detections that appeared seems to confirm the idea that the scanning habits which observers use are highly related to previously learned reading habits." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spatial organization of distractors in visual search.

This paper investigates visual search in displays in which distractors are spatially grouped. The effect on detection of target position within a spatially grouped 2-dimensional display containing 2 distractor types were examined. The authors compared detection in grouped displays with detection in 2 kinds of control display, homogeneous (one distractor type) and ungrouped (2 distractor types), to determine whether detection in grouped displays would be more similar to efficient detection in homogeneous displays than to inefficient detection in ungrouped displays. Findings show relatively efficient detection in group displays. Detection of targets at the border of two regions where distractors are coherent is easier than can be predicted by models that do not take spatial organization into account. Thus, models of visual search need to incorporate effects of spatial organization in addition to bottom-up difference calculations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)