Dynamic grouping and interpolation induced by flickering stimuli

A novel grouping and interpolation effect induced by flickering stimuli is described: a matrix of flickering elements forms stick-like clusters, then the clusters gradually dissociate back into the discrete elements within a few seconds. On continuous viewing, this flicker-induced grouping and interpolation repeatedly disappeared and reappeared. The perceived strength of this phenomenon peaked when the luminance of the flickering elements was alternately darker and lighter than the background; thus, the reversal of the luminance contrast polarity was responsible for flicker-induced grouping. The temporal dynamics of flicker-induced grouping showed the stochastic nature of perceptual alternation, which depended on the global structure of the stimulus. From these results, it is concluded that flicker-induced grouping reflects multiple stages of visual processing.     

Erratum: Computer‐based teaching of Kanji construction and writing in a student with developmental disabilities. By Hiroshi Sugasawara and Jun‐ichi Yamamoto

The above article (DOI: 10.1002/bin.271 ) was published online in Early View on 3 December 2008. A printing error was subsequently identified in the article. Page 1: Incorrect author affiliation. ‘Keio Advanced Research Center (KARC)’ should be ‘Department of Psychology’     

Cross-cultural Protective Effects of Neighborhood Collective Efficacy on Antisocial Behaviors: Mediating Role of Social Information Processing

Studies on the prevention of antisocial behavior in neighborhoods through efficacious social control have focused on collective efficacy as the theoretical mechanism by which children at the community level can be successfully socialized to develop an aversion to antisocial behaviors. We hypothesized that the effect of collective efficacy within communities on antisocial behaviors could be mediated by social-information-processing biases and tested the generality of these mediation effects for undergraduates (N = 929) in Japan, China, South Korea, and the United States, countries with widely varying cultures and political systems. Structural equation modeling revealed that the effects of collective efficacy on antisocial behaviors were perfectly mediated by social-information-processing biases. Findings also confirmed the generality of these mediational effects in all four countries investigated.     

Rapid learning by walking observers wearing a reversing or inverting prism

We measured the initial rapid learning of walking observers who wore an up-down inverting or left-right reversing prism. This prism-walking version of the 'mirror-drawing' experiment revealed that the learning curve as a function of the trial number was the same as that typically acquired from a traditional mirror-drawing experiment. We suggest that the initial short-term learning process involved in prism walking is similar to that in mirror drawing and is related to the high-level decision-making process involved in visuo-motor planning of actions with feedback from transformed vision.     

Illusory motion produced by dichoptic stimuli during saccades

A new motion illusion is reported in which saccadic eye movements can produce a perceived jump of a static stimulus presented dichoptically. In three experiments, observers made saccades while viewing a stationary stimulus consisting of a disk and random dots presented separately to the two eyes. In experiments 1 and 2, by measuring the strength of the perceived motion and the velocity of binocular eye movements, we found that (a) motion ratings were high for the stimulus that contained a large interocular difference in luminance, and (b) the saccadic strategy of the observer was virtually identical across different stimulus conditions. In experiment 3, by measuring the detectability of a short temporal gap introduced into the stimulus around saccades, we found that saccadic suppression was normal in the dichoptic presentation. We discuss possible mechanisms underlying the illusory motion.     

Threading dislocation with b=c+2a in 4H-SiC as determined by LACBED

The Burgers vectors of the so-called threading screw dislocations (a total of 28 dislocations) in 4H-SiC were determined by large-angle convergent-beam electron diffraction. A new type of TSD, that is, b = c + 2a dislocation, was identified. Thus, all of the four types of TSD predicted by Onda et al. [Phil. Mag. Lett. 93 (2013) p.591] were identified.     

Consistent air flow to the face facilitates vection

We examined whether a somatosensory cue suggesting forward self-motion facilitated vection. We provided a consistent air flow to subjects' faces by using an electric fan.Vection strength was increased when the air flow was provided.     

Type-based associations in grapheme-color synaesthesia revealed by response time distribution analyses

Determining the nature of binding in grapheme-color synaesthesia has consequences for understanding the neural basis of synaesthesia and visual awareness in general. We evaluated type- and token-based letter-color binding using a synaesthetic version of the object-reviewing paradigm. Although mean response times failed to reveal any significant differences between synaesthetes and control participants, RT analyses with ex-Gaussian distributions revealed that the response facilitation in the synaesthesia group reflected type representations exclusively, while response facilitation in the control group, who learned letter-color associations, was dominated by token representations. Thus, letter-color associations in associator synaesthetes are type-based, and do not involve binding to object tokens, consistent with their subjective reports. Contrary to recent studies that failed to find differences between synaesthetes and non-synaesthetes with behavioral measures, response time distribution analyses indicate that color sensations in synaesthetes are not simply the extreme form of normal letter-color associations, and cannot be attributed to demand characteristics.     

Vection can be induced without global-motion awareness

A new vection illusion is reported. Vection was induced even though there was no consciously perceived global display motion corresponding to the self-motion. The resulting experience can be summarised as: "I feel that I am moving but I do not know why".