The Localization of Pitch Perception on the Basilar Membrane

Durations of four categories of perceptions in the binocular rivalry of 3.9° bright contours were considered. Distributions of durations of perceptions of each of the rivalry categories and of all rivalry reports together were tested against five standard distributions. The empirical distributions showed no tendency to fit any of the standard theoretical distributions well. The results suggest that speculations concerning the underlying mechanisms of binocular rivalry based on observations of the durations of rivalry reports may not be useful until the distributions of durations are satisfactorily described.     

Stochastic properties of binocular rivalry alternations

Previous researches have demonstrated that the successive phase durations in binocular rivalry are independent. These findings are confirmed and extended to chromatic stimuli. The nature of the function that is shown to describe the distribution of the dominance phase durations is consistent with the independence of successive phases and suggests that a parallel may exist between binocular rivalry and the perceptual reversal of ambiguous figures.

     

Binocular rivalry and semantic processing: out of sight, out of mind

Previous studies of binocular rivalry have shown that some aspects of a phenomenally suppressed stimulus remain available for visual analysis. The question remains, however, whether this analysis extends to the case of semantic information. This experiment examines that question using a semantic-priming paradigm in which prime words were briefly flashed to an eye during either dominance or suppression phases of binocular rivalry. Reaction times on a lexical-decision task were significantly shortened (the semantic-priming effect) only when prime words were presented to an eye during dominance; suppression acted to impair word recognition and to eliminate semantic priming. These results are inconsistent with certain cognitive models of binocular rivalry.     

Binocular rivalry between single lines viewed as real images and afterimages

Binocular rivalry alternations between single lines oriented at 0 and 90 deg or 0 and 45 deg were measured. The lines were viewed as either real images or afterimages. The experiment was designed to determine whether or not a vertical (0 deg) line predominates for longer than a nonvertical line and to compare the temporal characteristics of rivalry between real images and afterimages. There were no systematic differences in predominance durations under any of the rivalry pairings or viewing conditions. The dominance periods for rivalry between afterimages were longer than those for real images. Frequency distributions of the dominance periods were all positively skewed, and the parameters of the fitted gamma distributions were similar in all cases. Tests of the sequential dependence of successive dominance periods indicated that they were independent for both real images and afterimages.     

How context influences predominance during binocular rivalry

Variations in the predominance of an object engaged in binocular rivalry may arise from variations in the durations of dominance phases, suppression phases, or both. Earlier work has shown that the predominance of a binocular rival target is enhanced if that target fits well-via common color, orientation, or motion-with its surrounding objects. In the present experiments, the global context outside of the region of rivalry was changed during rivalry, to learn whether contextual information alters the ability to detect changes in a suppressed target itself. Results indicate that context will maintain the dominance of a rival target, but will not encourage a suppressed target to escape from suppression. Evidently, the fate of the suppressed stimulus is determined by neural events distinct from those responsible for global organization during dominance. To reconcile diverse findings concerning rivalry, it may be important to distinguish between processes responsible for selection of one eye's input for dominance from processes responsible for the implementation and maintenance of suppression.     

Increment detection thresholds during binocular rivalry suppression

In two experiments, two-choice forced-choice duration thresholds for increment test flashes were estimated during phases of rivalry suppression and nonsuppression and for a nonrivalry monocular control condition. In both experiments thresholds of both eyes of each S were measured and, to maximize correct detections, feedback was given after every trial and Ss were relieved of the task of continually reporting changes in rivalry phases. Results of both experiments support the conclusion that suppression constitutes an elevation in threshold, on the order of .5 log units relative to thresholds found during nonsuppression and monocular conditions. These data, in concert with others, reinforce the general conclusion that rivalry suppression is an inhibitory state that nonselectively attenuates all classes of inputs falling within the spatial boundaries of the suppressed target.     

Amplitude of visual suppression during the control of binocular rivalry

To investigate the precise mechanism of control of binocular rivalry, Ss were instructed to attend actively to whichever pattern was momentarily in the nonsuppression phase. Test stimuli were presented tachistoscopically for recognition in either phase of rivalry. Because the differential recognition between nonsuppressed and suppressed phases was no greater for an active condition than for a passive viewing condition, it was concluded that control is not mediated by varying the amplitude of the suppression effect. This result was consistent with control that is exercised by selecting the eye to receive a constant amplitude suppression. In addition, it was found that visual sensitivity of rivalry nonsuppression and nonrivalry were the same for the ocular dominant eye but different for the nondominant eye.     

The effect of orientation in binocular contour rivalry of real images and afterimages

Binocular rivalry was investigated using gratings of different orientations in three experiments. No consistent effects of orientation were found for predominance measures of rivalry between real images. Rivalrous afterimages, on the other hand, did exhibit orientation selectivity: vertical gratings were visible for longer than were 45-deg gratings. This effect was compared to the similar orientation selectivity found for monocular observation of grating afterimages. Comparisons of binocular rivalry between real images and afterimages were made in terms of the frequency distributions of the dominance periods.     

Monocular and binocular rivalry between contours.

The temporal characteristics of binocular and monocular rivalry between orthogonal gratings of the same or complementary colours were investigated. Rivalry was measured in terms of the dominance of either grating or the visibility of composites comprised of parts of both gratings. The total duration for which either grating was dominant was significantly longer in binocular rivalry between gratings of complementary colours. A comparison of binocular and monocular rivalry indicated considerable phenomenal differences between them. Dominance in binocular rivalry corresponds to the visibility of one grating alone; this occurs rarely in monocular rivalry, which is characterized by fluctuations in the distinctiveness of the gratings. The changes in distinctiveness are influenced by colour in a similar manner to that in binocular rivalry, and the frequencies of fluctuations are higher for gratings of complementary colours.     

Detecting olfactory rivalry

Olfactory rivalry can occur when a binary mixture is sniffed repeatedly, with one percept dominating then the other. Experiment 1 demonstrated olfactory rivalry using several new techniques. Experiments 2 and 3 examined whether participants can notice rivalry. Participants received trials composed of odor pairs: either a mixture followed by the same mixture; or a pure odor followed by the same pure odor. On some trials participants judged whether the two stimuli were the same or different, to see if they could detect rivalry. On other trials participants judged the quality of each odor, allowing us to determine whether rivalry occurred. We found evidence for rivalry when we compared reports of odor quality for one stimulus and then the other, but no evidence that participants could detect this change. These findings are consistent with the idea that people can experience olfactory illusions, but may not know they have occurred.     

When your brain decides what you see: grouping across monocular, binocular, and stimulus rivalry

Research suggests that the neural concomitants of visual rivalry are contingent on the stimulus parameters, implying the existence of three different types of rivalry. Binocular rivalry (dissimilar patterns are presented, one to each eye) is seemingly mediated by interactions between pools of monocular neurons. Monocular rivalry (superimposed patterns are presented to one or both eyes) is presumably the result of competition between neural representations of the patterns. Stimulus rivalry (dissimilar patterns are swapped rapidly between the two eyes) is independent of eye of origin. In the experiment reported here, we integrated these three different types of rivalry into one stimulus. We found that perceptual alternations span the three types of rivalry, demonstrating that the brain can produce a coherent percept sourced from three different types of visual conflict. This result is in agreement with recent work suggesting that the resolution of competitive visual stimuli is mediated by a general mechanism spanning different levels of the visual-processing hierarchy.     

Binocularity and visual search—Revisited

Binocular rivalry is a phenomenon of visual competition in which perception alternates between two monocular images. When two eye’s images only differ in luminance, observers may perceive shininess, a form of rivalry called binocular luster. Does dichoptic information guide attention in visual search? Wolfe and Franzel (Perception & Psychophysics, 44(1), 81–93, 1988) reported that rivalry could guide attention only weakly, but that luster (shininess) “popped out,” producing very shallow Reaction Time (RT) × Set Size functions. In this study, we have revisited the topic with new and improved stimuli. By using a checkerboard pattern in rivalry experiments, we found that search for rivalry can be more efficient (16 ms/item) than standard, rivalrous grating (30 ms/item). The checkerboard may reduce distracting orientation signals that masked the salience of rivalry between simple orthogonal gratings. Lustrous stimuli did not pop out when potential contrast and luminance artifacts were reduced. However, search efficiency was substantially improved when luster was added to the search target. Both rivalry and luster tasks can produce search asymmetries, as is characteristic of guiding features in search. These results suggest that interocular differences that produce rivalry or luster can guide attention, but these effects are relatively weak and can be hidden by other features like luminance and orientation in visual search tasks.     

Aftereffects in binocular rivalry

Five experiments are reported in which the aftereffect paradigm was applied to binocular rivalry. In the first three experiments rivalry was between a vertical grating presented to the left eye and a horizontal grating presented to the right eye. In the fourth experiment the rivalry stimuli consisted of a rotating sectored disc presented to the left eye and a static concentric circular pattern presented to the right. In experiment 5 rivalry was between static radiating and circular patterns. The predominance durations were systematically influenced by direct (same eye) and indirect (interocular) adaptation in a manner similar to that seen for spatial aftereffects. Binocular adaptation produced an aftereffect that was significantly smaller than the direct aftereffect, but not significantly different from the indirect one. A model is developed to account for the results; it involves two levels of binocular interaction in addition to monocular channels. It is suggested that the site of spatial aftereffects is the same as that for binocular rivalry, rather than sequentially prior.     

Delinquency and Child Guidance: Selected Papers by August Aichhorn Edited by Otto Fleischmann,Paul Kramer and Helen Ross

A year-long psychotherapy group consisting of two co-therapists and eight grandmothers who were parenting their daughters' children is presented. Three models that correspond to the co-therapists' psychoanalytic developmental orientation were used to describe the group phases of development. A number of themes that emerged at different points in the group's life are delineated. They include: authority, control, sibling rivalry, the generation gap, dealing with schools, illness and mortality, isolation, defensiveness, anger, fear of going crazy, guilt, shame, separation, and abandonment. Transference and countertransference issues are also discussed.     

Adolescent narcissism and interpersonal trust: A cross‐lagged study

In recent years, narcissism has been attracting considerable interest by researchers because of its enigmatic constructs. To enhance our understanding of narcissists’ psychosocial functioning, considering the relationship between narcissism and interpersonal trust is crucial. This study aimed to investigate how narcissistic admiration and rivalry are associated with interpersonal trust. To gain a more nuanced understanding, a cross‐lagged design was conducted at two time points that were six months apart. In total, 357 adolescents (M_age = 16.33 years) completed the Narcissistic Admiration and Rivalry Questionnaire (NARQ) and the Interpersonal Trust Scale. The results showed that narcissistic admiration positively predicted interpersonal trust while narcissistic rivalry negatively predicted interpersonal trust at the second time point. However, interpersonal trust did not predict subsequent levels of narcissistic admiration and rivalry. These findings enhanced our understanding by showing that narcissistic admiration and rivalry have different effects on interpersonal trust, and that they remain relatively stable during a six‐month period.     

A Social Psychological Approach to Enduring Rivalries

The recent scholarly work on the concept of enduring rivalries offers a promising way to examine strategic interaction among dyads of states over extended periods of time. A focus on rivalry, and on the mechanisms that provide for such interaction, may offer a way to bridge existing theories of international relations that rely exclusively on structure or process. Unfortunately, the potential for theory-building has not been fully realized because research into rivalry has tended to be inductive. This paper seeks to rectify that problem by situating the rivalry concept within a social psychological approach to international relations. The rivalry concept is appropriately located in a theoretical approach that views the international system as a social system where actors are conditioned by mechanisms of competition and socialization.     

Plaid motion rivalry: correlates with binocular rivalry and positive mood state

Recently Hupé and Rubin (2003, Vision Research 43 531- 548) re-introduced the plaid as a form of perceptual rivalry by using two sets of drifting gratings behind a circular aperture to produce quasi-regular perceptual alternations between a coherent moving plaid of diamond-shaped intersections and the two sets of component 'sliding' gratings. We call this phenomenon plaid motion rivalry (PMR), and have compared its temporal dynamics with those of binocular rivalry in a sample of subjects covering a wide range of perceptual alternation rates. In support of the proposal that all rivalries may be mediated by a common switching mechanism, we found a high correlation between alternation rates induced by PMR and binocular rivalry. In keeping with a link discovered between the phase of rivalry and mood, we also found a link between PMR and an individual's mood state that is consistent with suggestions that each opposing phase of rivalry is associated with one or the other hemisphere, with the 'diamonds' phase of PMR linked with the 'positive' left hemisphere.     

What causes alternations in dominance during binocular rivalry?

Several mechanisms have been proposed to account for perceptual alterations during binocular rivalry, including neural adaptation and neural noise. However, the importance of neural adaptation for producing perceptual alterations has been challenged in several articles (Y.-J. Kim, Grabowecky, & Suzuki, 2006; Moreno-Bote, Rinzel, & Rubin, 2007). We devised an “online” adaptation procedure to reexamine the role of adaptation in binocular rivalry. Periods of adaptation inserted into rivalry observation periods parametrically alter the dynamics of rivalry such that increased adaptation duration decreases dominance duration, which cannot be accounted for by neural noise. Analysis of the average dominance durations and their variance (coefficient of variation) provides evidence for an increasingly important role of noise in rivalry alternations as a given dominance period continues in time, consistent with recent computational models.     

Perceived depth in the 'sieve effect' and exclusive binocular rivalry

An impression of a surface seen through holes is created when one fuses dichoptic pairs of discs, with one member of each pair black and the other member white. This is referred to as the 'sieve effect'. The stimulus contains no positional disparities. Howard (1995, Perception 24 67-74) noted qualitatively that the sieve effect occurs when the rivalrous regions are within the range of sizes, contrasts, and relative sizes where exclusive rivalry occurs, rather than binocular lustre, stimulus combination, or dominant rivalry. This suggests that perceived depth in the sieve effect should be at a maximum when exclusive rivalry is most prominent. We used a disparity depth probe to measure the magnitude of perceived depth in the sieve effect as a function of the sizes, contrasts, and relative sizes of the rivalrous regions. We also measured the rate of exclusive rivalry of the same stimuli under the same conditions. Perceived depth and the rate of exclusive rivalry were affected in the same way by each of the three variables. Furthermore, perceived depth and the rate of exclusive rivalry were affected in the same way by changes in vergence angle, although the configuration of the stimulus surface was held constant. These findings confirm the hypothesis that the sieve effect is correlated with the incidence of exclusive rivalry.