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".     

Perceptual simulations can be as expressive as first-order logic

Theories asserting that human reasoning is based on perceptual simulations often suppose these simulations are of concrete individual objects and the specific relations that hold among them. However, much human knowledge involves assertions about which relations do not hold, generalities over large numbers of objects and conditional facts. Can simulation theories explain how the mind represents these forms of knowledge, or are they inferior in their expressive power to knowledge representation schemes based on logical formalisms designed specifically to deal with negative, conditional and quantificational knowledge? In this paper, we show how assertions about mental simulations can in fact straightforwardly express all the concepts that comprise first-order logic, including negation, conditionals and both universal and existential quantification. We also speculate on how to extend this approach to deal with probabilistic and more expressive logics.     

What skilled typists don’t know about the QWERTY keyboard

We conducted four experiments to investigate skilled typists’ explicit knowledge of the locations of keys on the QWERTY keyboard, with three procedures: free recall (Exp.?1), cued recall (Exp.?2), and recognition (Exp.?3). We found that skilled typists’ explicit knowledge of key locations is incomplete and inaccurate. The findings are consistent with theories of skilled performance and automaticity that associate implicit knowledge with skilled performance and explicit knowledge with novice performance. In Experiment?4, we investigated whether novice typists acquire more complete explicit knowledge of key locations when learning to touch-type. We had skilled QWERTY typists complete a Dvorak touch-typing tutorial. We then tested their explicit knowledge of the Dvorak and QWERTY key locations with the free recall task. We found no difference in explicit knowledge of the two keyboards, suggesting that typists know little about key locations on the keyboard, whether they are exposed to the keyboard for 2 h or 12 years.     

Memory Characteristics in Relation to Age and Community Identity: The Influence of Rehearsal on Visitors’ Recollections of the 2005 Aichi World Exposition,Japan

ABSTRACT

This study investigated autobiographical memory characteristics in relation to age and community identity using Japanese visitors’ recollections of their experiences of the 2005 Aichi World Exposition in Japan, which they had attended 4 years past. A total of 82 visitors completed a 38-item Memory Characteristics Questionnaire (MCQ). Age was grouped in 2 levels—younger adult visitors (ages 18 to 30) and older adult visitors (ages 60 to 82)—and community identity by 2 distinct community groupings—visitors from Kansai area and visitors from Aichi area. Autobiographical memory characteristics, reflected by the factors of the MCQ, were explored through analysis of variance in terms of age and community identity to determine the influence on visitors’ long-term memories of the Aichi Expo. Explanations of the significant effects include sociocultural identities that motivate recollection and rehearsal activity and lead to clear or improvised autobiographical memories of the event.     

Nanomachining of nanocrystalline nickel by focused ion beam

Nanocrystalline and sub-microcrystalline samples of nickel have been machined by a focused Ga⁺ ion beam (30?keV and 187?pA) at doses of 8.92?×?10¹⁶?–?2.68?×?10¹⁸ ions/cm² and their surface topography was investigated by atomic force microscopy (AFM). Values of the root-mean-square (RMS) roughness increase with increasing ion dose. The surfaces of the nanocrystalline Ni were smoother than those of the sub-microcrystalline Ni, indicating that smoothing due to diffusion for the former works more effectively than that for the latter.     

Selective attention to stimulus features modulates interocular suppression

Psychological and neurophysiological studies have shown that attention modulates various sorts of perceptual processing. Here, we report that attention affects the perceptual dominance of binocular rivalry. Experiments using a dichoptic masking paradigm revealed that when an observer was attending to one of the two orientations of the elements of a monocular texture, a texture briefly presented to the opposite eye suppressed the perception of the elements with the attended orientation, while the elements with the orientation which was ignored sustained their dominance. Moreover, subsequent experiments indicated that the suppression depended on the orientation of the texture elements constituting the mask, but was independent of their locations. These results suggest that attention to specific features modulates interocular suppression in a mode which is different from that found in a previous study [Ooi and He, 1999 Perception 28 551 -574].     

The aperture problems in the Pulfrich effect

The Pulfrich effect yields a perceived depth for horizontally moving objects but not for vertically moving ones. In this study the Pulfrich effect was measured by translating oblique lines seen through a circular window, which made motion direction ambiguous. Overlaying random dots that moved horizontally, vertically, or diagonally controlled the perceptual motion direction of the lines. In experiment 1, when the lines were seen to move horizontally, the effect was strongest in spite of the same physical motion of the lines. Experiment 2 was performed to test the above conditions again, excluding the Pulfrich effect of the dots on the depth of the lines. The overlaid dots were presented to one eye only. The result showed that the Pulfrich effect of the lines was persistently strong in spite of the perceptual changes in motion direction. Experiment 3 also showed that the Pulfrich depth was independent of the perceived horizontal speed in a plaid display. The Pulfrich effect was determined by measuring the horizontal disparity component, independently of the perceived motion direction. These results demonstrate that the aperture problems in motion and stereopsis in the Pulfrich effect are solved independently.     

Information regarding structure and lightness based on phenomenal transparency influences the efficiency of visual search

Phenomenal transparency reflects a process which makes it possible to recover the structure and lightness of overlapping objects from a fragmented image. This process was investigated by the visual-search paradigm. In three experiments, observers searched for a target that consisted of gray patches among a variable number of distractors and the search efficiency was assessed. Experiments 1 and 2 showed that the search efficiency was greatly improved when the target was distinctive with regard to structure, based on transparency. Experiment 3 showed that the search efficiency was impaired when a target was not distinctive with regard to lightness (ie perceived reflectance), based on transparency. These results suggest that the shape and reflectance of overlapping objects when accompanied by transparency can be calculated in parallel across the visual field, and can be used as a guide for visual attention.     

Modification of depth and distance perception caused by long-term wearing of left-right reversing spectacles

For 35 to 39 days, four observers wore continuously left-right reversing spectacles which pseudoscopically reverse the order of binocular disparity and direction of convergence. In three tests, we investigated how the visual system copes with the transformation of depth and distance information due to the reversing spectacles. In stereogram observation, after a few days of wearing the spectacles. the observers sometimes perceived a depth order which was opposite to the depth order that they had perceived in the pre-spectacle-wearing period. Monocular depth cues contributed more to depth perception in the spectacle-wearing period than they did in the pre-spectacle-wearing period. While the perceived distance significantly decreased during the spectacle-wearing period, we found no evidence of adaptive change in distance perception. The results indicate that the visual system adapts itself to the transformed situation by not only changing the processing of disparity but also by changing the relative efficiency of each cue in determining apparent depth.     

A historical review of long-term visual-transposition research in Japan

Since 1960, more than 37 long-term experiments have been performed in Japan concerning up-down and left-right reversal and inversion, yet these contributions to a field of study pioneered by Stratton 100 years ago remain unfamiliar outside Japan, as most articles have not appeared in English. Japanese researchers have focused on several basic elements of perceptual systems, such as intersensory relationships, sensory-motor coordination, spatial frames of reference, and position constancy. Although subjects have not adapted perfectly to a transposed world in the course of these two- or three-week scale experiments, important data, particularly concerning left-right reversed vision, have been generated. I, myself, have conducted all three types of visual transposition experiments a number of times and propose a model comprised of three subsystems: that is, top-down, bottom-up, and sensory-motor systems. Central to my theory is the notion that the essential change has occurred in the subject's own body image, and that the spatial representation of the body image is visual in nature, not non-visual proprioception (as deduced from Harris' (1965) hypothesis).