Intensity dependence of perceived duration: Data, theories, and neural integration.

Evaluates 2 theoretical models suggested to explain studies of the effect of stimulus intensity on the perceived duration of brief light flashes. Some studies found a direct relationship between the 2 variables; others found an indirect relationship. Each model suggests that an additional variable interacts with stimulus intensity. Proposed variables have included the nature of the judgment and the absolute intensity. The present evaluation indicates that both of the proposed variables play a role and that a melding of the models could best account for this phenomenon. The melding incorporates known time- and intensity-dependent characteristics of neural integration into the behavioral performance. The evaluation also indicates that future experiments on this problem will be most informative if they (a) give particular attention to the role of instructions, (b) explore an adequate range of intensities, and (c) strictly control adaptive state. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Improving eyewitness identifications from lineups: Simultaneous versus sequential lineup presentation.

Investigated the effectiveness of sequential lineup presentation as a means of reducing false identifications with little or no loss in accurate identifications. A crime was staged for 240 unsuspecting eyewitnesses (undergraduates) either individually or in pairs. One-fourth of the Ss attempted identifications in each of 4 lineup conditions: 6 pictures were presented either simultaneously, as used in traditional procedures, or sequentially, in which yes/no judgments were made for each picture; each procedure either contained the photograph of the criminal–confederate or a picture of a similar looking replacement. Results indicate that sequential lineup presentation significantly reduced false identifications but did not significantly influence correct identifications when compared with a simultaneous procedure. It is concluded that sequential presentation of lineups can reduce false identifications of innocent suspects by reducing eyewitnesses' reliance on relative-judgment processes. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Magnitude estimation of perceived odor intensity: Empirical and theoretical properties.

Four subjects judged the odor intensities of 7 pyridine concentrations and a blank. Computer simulations of a judgment model were compared with the empirical data. The model generates data patterns that closely mimic empirical findings. The following patterns were confirmed: (a) A power function relates magnitude estimates and concentration with an exponent in the range of 0.7 to 1.0. (b) The exponent fluctuates so that the level constant is negatively correlated with the exponent. (c) The standard deviation of the responses is a negatively accelerated function of the mean. (d) The skewness of the responses is relatively high for low concentrations and declines toward zero with increasing concentration. (e) The correlation between responses to successive stimuli is highest when successive concentrations are similar. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed attention prolongs the perceived duration of a brief stimulus

Stelmach, Herdman, and McNeil (1994) suggested recently that the perceived duration for attended stimuli is shorter than that for unattended ones. In contrast, the attenuation hypothesis (Thomas & Weaver, 1975) suggests the reverse relation between directed attention and perceived duration. We conducted six experiments to test the validity of the two contradictory hypotheses. In all the experiments, attention was directed to one of two possible stimulus sources. Experiments 1 and 2 employed stimulus durations from 70 to 270 msec. A stimulus appeared in either the visual or the auditory modality. Stimuli in the attended modality were rated as longer than stimuli in the unattended modality. Experiment 3 replicated this finding using a different psychophysical procedure. Experiments 4-6 showed that the finding applies not only to stimuli from different sensory modalities but also to stimuli appearing at different locations within the visual field. The results of all six experiments support the assumption that directed attention prolongs the perceived duration of a stimulus.     

Changes in the perceived duration of a narrowband sound induced by a preceding stimulus.

The authors show that a narrowband noise (NBN) is perceived as longer when presented immediately after a wideband noise (WBN), compared to when the WBN is absent. This effect depended on the WBN’s frequency spectrum overlapping that of the NBN, and it increased as the duration of the WBN increased up to 300 ms. It decreased when a silent gap was introduced between the WBN and NBN, but remained significant for an easily detectable gap of 40 ms. A correlate of the effect was observed in the mismatch negativity (MMN) to a deviant stimulus, consisting of a WBN + NBN, presented in a sequence of more common isolated WBNs. The MMN latency was longer for an on-frequency than for an off-frequency WBN; and, more importantly, the size of this difference correlated across participants with the difference in perceived duration. A rhythm-adjustment experiment showed that the presence of an on-frequency WBN immediately preceding a tone caused that tone to be heard as starting earlier than when the WBN was absent. The results are discussed in relation to the continuity illusion and models of duration encoding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dominance statistics: Ordinal analyses to answer ordinal questions.

Much behavioral research involves comparing the central tendencies of different groups, or of the same Ss under different conditions, and the usual analysis is some form of mean comparison. This article suggests that an ordinal statistic, d, is often more appropriate. d compares the number of times a score from one group or condition is higher than one from the other, compared with the reverse. Compared to mean comparisons, d is more robust and equally or more powerful; it is invariant under transformation; and it often conforms more closely to the experimeter's research hypothesis. It is suggested that inferences from d be based on sample estimates of its variance rather than on the more traditional assumption of identical distributions. The statistic is extended to simple repeated measures designs, and ways of extending its use to more complex designs are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ordinal knowledge: Number names and number concepts in Chinese and English.

Assessed the impact of linguistic differences in ordinal number names on children's acquisition and use of ordinal numbers and their understanding of ordinal concepts. Elementary school children (aged 5.4–10.6 yrs) in China and the US performed a series of tasks assessing understanding of ordinal numbers and concepts. The results show differences in the acquisition and use of ordinal numbers corresponding to linguistic differences in ordinal names in their native languages. On tasks assessing children's conceptual knowledge of ordinal relations, a more complicated picture emerged. These results suggest that (1) children induce their language's set of ordinal number names by generalization based on rules sanctioned by early examples, and (2) the relation between ordinal names and ordinal concepts is a complex one, with language only one source of difficulty in understanding ordinal relations. Implications for studies of the relation between linguistic structure and cognitive development are discussed, in particular the possibility that effects of linguistic differences may vary for different levels of development and for different aspects of cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Depression and perceived reinforcement: A reconsideration.

Evidence for the depressed S's hypersensitivity to any feedback about his performance and for the reversibility of depression-based perceptual deficits suggests that the depressed S can perceive response–reinforcement contingencies correctly, but only if given unassailable evidence of the efficacy of his actions. A high rate of response-contingent reinforcement is one instance of such evidence. The authors predicted that depressed Ss would misperceive skill task rewards under low- but not under high-reinforcement conditions. Changes in verbalized expectancies of success on skill and chance tasks at either 50 or 75% reinforcement rate were compared for 20 depressed and 20 nondepressed college students. Contrary to prediction, depressed Ss in no way differed from the nondepressed on the skill task at 50% reinforcement, and they produced larger expectancy changes on the chance task than did nondepressed Ss at 75% reinforcement. Results argue against the view that the depressed person misperceives response reinforcement contingencies, and they suggest instead that the depressed person overgeneralizes from any experience of success or failure in forming expectations for future successes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Linking perceived unfairness to physical health: The perceived unfairness model.

Can perceiving unfairness influence physical health? To address this question the authors propose the Perceived Unfairness Model, synthesized from psychological and epidemiological research. The model starts from the premise that perceiving unfairness, directed at beings to which the perceiver is emotionally attached, activates a cascade of psychological and physical processes. This cascade may be experienced by low or high status group members, and by the target or observer of the perceived unfairness. With repeated episodes, the effects of perceiving unfairness may accumulate and compromise physical health. Whether perceiving unfairness is potentially toxic or benign is a function of two key components of social location: identity relevance and helplessness to redress the unfairness. The authors conclude by discussing directions for developing the model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Simultaneous determination of phosphate and silicate in waste water by sequential injection analysis

A sequential injection analysis system for the simultaneous determination of phosphate and silicate in waste water is proposed. The method is based on the formation of yellow vanadomolybdophosphate and molybdosilicate, respectively, in addition to the use of large sample volumes. The mutual interference between both analytes was eliminated by selection of the appropriate acidity and by sample segmentation with oxalic acid. The calibration graph for phosphate and silicate is linear up to 12 mg l-1 P and 30 mg l-1 Si, respectively. The detection limits are 0.2 mg l-1 P and 0.9 mg l-1 Si. The method provides a throughput of 23 samples h-1 with a relative standard deviation < 1.4% for phosphate and < 4% for silicate. The method was found to be suitable for the determination of these species in waste water samples.     

Dominance and outcome: A sequential examination.

Used a statistical dependency definition of control to examine J. Haley's (1963) contention that successful counseling is characterized by the counselor being in control, or dominant. The 3 best and the 3 worst dyads, in terms of both client- and counselor-rated outcome, were selected from 15 time-limited counseling dyads at a university counseling center. All interactions were rated for topic-initiating or topic-following responses. The extent to which each participant's topical response was predictable based on the other's previous response was calculated. These 2 indices of dependence, one for the client and one for the counselor, were then compared for differences. Results demonstrate that counselors were dominant in the successful dyads, whereas dependency was equal in the unsuccessful dyads. To determine if these results were associated with certain stages of the process of the successful dyads, a post hoc analysis was conducted, testing for dependency differences across the stages found by the author and P. B. Ray (see record 1984-16374-001). Counselor dominance was found only in the middle (conflict) stage. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mental stress of long duration: EMG activity, perceived tension, fatigue, and pain development in pain-free subjects

The study examined the relationship between pain development in the shoulder, neck, and facial regions and the EMG activity of underlying muscles, during prolonged exposure to a mental stressor. The subjective perception of tension and fatigue was recorded. Thirty-six subjects were exposed to a two-choice reaction-time test for 1 hour. Electromyographic (EMG) recordings were performed bilaterally over the frontalis, temporalis, splenius, and trapezius muscles. Pain and perceived tension were scored on a visual analog scale, and fatigue on a Borg scale. Pain development was most pronounced in the shoulder and neck region. There was a weak tendency of those reporting pain in the shoulder region to generate higher EMG activity in the trapezius relative to those with no shoulder pain at the end of the test. No such relationship was observed for the other muscles. Perceived tension during the test was weakly related to pain and strongly related to fatigue at the end of the test, but not to EMG level. It is concluded that the mean level of the EMG response is of little consequence for pain development during stressful conditions. It is argued that other physiological responses such as prolonged activity in low-threshold motor units, whereby the surface EMG response can serve as a marker, can be important for shoulder pain originating in the trapezius muscle.     

Ordinal position, approval motivation, and interpersonal attraction.

Attempted to incorporate ordinal position effects within approval-dependency theory. 257 undergraduates completed the Marlowe-Crowne Social Desirability Scale (SDS) and birth-order data prior to the actual experiment. Bogus SDSs were completed by the E to correspond to the same score level of the individual Ss but with either 75 or 50% item agreement. The 3 * 2 analyses of variance for SDS scores and expressed attraction indicate that 1st- and middle-born females had higher SDS scores and expressed more attraction. A separate analysis indicates that although only-born females had similar SDS scores, they expressed significantly more attraction. Correlations between SDS scores and expressed attraction were significant. Results are interpreted as being congruent with approval-dependency theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mathematicians: The creative researcher and the average PhD.

A sample of mathematicians, 29 comparison Ss, is shown to differ from 27-34 creative research scientists in demographic and personality characteristics. Creative Ss were more flexible and richer in personality than comparison Ss, though not higher in personal ascendance or in IQ. They were more often the eldest child in their family and described their mothers with more respect and warmth. They came from higher socioeconomic backgrounds, but the native-born creatives came from less privileged backgrounds than have been reported for eminent scientists. The creative mathematicians show less predominant Protestant and American-born influence than eminent scientists. (28 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ordinal Process Dissociation and the Measurement of Automatic and Controlled Processes.

The process-dissociation equations (L. Jacoby, 1991) have been applied to results from inclusion and exclusion tasks to derive quantitative estimates of the influence of controlled and automatic processes on memory. This research has provoked controversies (e.g., T. Curran & D. Hintzman, 1995) regarding the validity of specific assumptions underlying the process-dissociation equations. In this article, the author explores the conclusions one can draw about the ordinal relations between automatic and controlled processes across experimental conditions from results in the inclusion and exclusion tasks. Given relatively neutral assumptions, this article presents and proves 6 theorems that allow investigators to draw conclusions about the ordinal relations between automatic and/or controlled processes across experimental conditions. An illustrative example is presented, and the current approach is compared with the original process-dissociation framework. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Tool use influences perceived shape and perceived parallelism, which serve as indirect measures of perceived distance.

Targets presented just beyond arm's reach look closer when observers intend to touch them with a reach-extending tool rather than without the tool. This finding is one of several that suggest that a person's ability to act influences perceived distance to objects. However, some critics have argued that apparent action effects were actually due to effects on the judgments rather than on the perception. In other words, the target does not actually look closer, but participants report that it is. To help counter this argument, the current experiments used an indirect measure of perceived distance: Participants reported perceived shape or perceived parallelism. The results revealed that triangles looked shorter and lines looked more horizontal to participants who reached with a tool, and therefore could reach the targets, than they did to participants who reached without the tool. These results demonstrate convergence across multiple types of judgments, a finding that undermines alternative, judgment-based accounts and suggests that the ability to reach an object changes the perceived distance to the object. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Comparison of two visual display presentations.

The applicability of the results of dial legibility studies based on slide presentations to legibility of actual dials was tested experimentally by comparison of time and error measures for reading actual dials, and reading slide projections of the dials. There was a slight but insignificant advantage in favor of panelmounted slides over projection of pictures of the slides. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Collective induction: Social combination and sequential transition.

[Correction Notice: An erratum for this article was reported in Vol 48(6) of Journal of Personality and Social Psychology (see record 2008-10978-001). One sentence reads incorrectly on page 610. The correct sentence is provided in the erratum.] 240 undergraduates, as individuals and 4-person cooperative groups, attempted to induce a rule that partitioned a deck of standard playing cards into exemplars and nonexemplars. A trial consisted of (a) individual member hypotheses, (b) group hypothesis (omitted in individual conditions), (c) choice of any of the cards, and (d) feedback on the exemplar or nonexemplar status of the card. Ss were instructed to select cards to confirm or disconfirm the current hypothesis, or received no such instructions. Groups had significantly more correct final hypotheses, plausible final hypotheses, and overall plausible hypotheses than individuals. Performance was better for both individuals and groups under control instructions than either instructions to select cards to confirm or disconfirm hypotheses. Social combination analyses and sequential transition analyses indicated that the groups were remarkably able to recognize and adopt the correct hypothesis if and only if it was proposed by at least 1 group member on some trial. Thus, the superiority of collective induction over individual induction was due to superior hypothesis evaluation by groups rather than to superior hypothesis formation by groups. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)