Transfer of spatial context from visual to haptic search

Under incidental learning conditions, spatial layouts can be acquired implicitly and facilitate visual search (contextual-cueing effect). We examined whether the contextual-cueing effect is specific to the visual modality or transfers to the haptic modality. The participants performed 320 (experiment 1) or 192 (experiment 2) visual search trials based on a typical contextual-cueing paradigm, followed by haptic search trials in which half of the trials had layouts used in the previous visual search trials. The visual contextual-cueing effect was obtained in the learning phase. More importantly, the effect was transferred from visual to haptic searches; there was greater facilitation of haptic search trials when the spatial layout was the same as in the previous visual search trials, compared with trials in which the spatial layout differed from those in the visual search. This suggests the commonality of spatial memory to allocate focused attention in both visual and haptic modalities.     

Axiomatic summary and deductions from Hering’s principles of visual direction

Hering’s principles of visual direction are summarized axiomatically, and deductions are presented. The deductions allow one to predict when veridical or nonveridical judgments of visual direction should occur and when apparent movement should be seen. These predictions agree with the results obtained in special viewing conditions. However, one of the limitations of the principles is that some of the predictions fail in “normal” viewing conditions.     

Emergence of response‐response relations

The present study examined whether bidirectional response‐response relations could be established without direct reinforcement. In AB training for 12 undergraduates, higher rates of touches to a white circle on the monitor screen (A1) produced two stimuli (B1 and B2) on half of the trials, whereas lower rates (A2) produced the same effect on the other half. Choosing one of the two stimuli was reinforced according to the preceding responding (A1B1 and A2B2). In BC training, touching a stimulus (B1 or B2) produced three white circles lined up horizontally on the screen, after which one of two different response sequences to the circles (left‐center‐right, C1 or C2, and right‐center‐left, C2 or C1) were reinforced, depending on the stimulus presented (B1C1 and B2C2). After AB and BC relations were established, 11 of 12 participants showed the emergence of untrained relations (BA, CB, AC, and CA) throughout five test sessions, and the remaining participant showed it in the first four test sessions. These response‐response relations were replicated with five other undergraduates and different trained relations.     

Polytypes of long-period stacking structures synchronized with chemical order in a dilute Mg–Zn–Y alloy

A series of structural polytypes formed in an Mg–1 at.%Zn–2 at.%Y alloy has been identified, which are reasonably viewed as long-period stacking derivatives of the hexagonal-close-packed Mg structure with alternate AB stacking of the close-packed atomic layers. Atomic-resolution Z-contrast imaging clearly revealed that the structures are long-period chemical-ordered as well as stacking-ordered; unique chemical order along the stacking direction occurs as being synchronized with a local faulted stacking of AB′C′A, where B′ and C′ layers are commonly enriched by Zn/Y atoms.     

The effect of marker size on the perception of an empty interval

Research shows that the time that is spent perceiving a brief visual stimulus is experienced as increasing as the size of the stimulus increases. We examined whether the experienced duration of time that is spent attending the perception of an empty interval—demarcated by the offset of one marker and the onset of a second marker— depends on the size of the markers themselves. Previous theories predict that the perceived time that is spent viewing offset-to-onset intervals decreases as the size of the markers increases, and that the perceived time that is spent viewing the markers increases. We demonstrated that empty intervals between the presentations of large markers were perceived to be longer in duration than those occurring between the presentations of small markers, and that the second marker was critical to this effect of physical size on apparent duration. We report that the size effect disappeared when the interval was filled with the presentation of a circle, and we conclude that the intensity of the second marker altered perceptions in an empty-interval-specific manner.     

The finite model property for BCK and BCIW

This paper shows that both implicational logicsBCK andBCIW have the finite model property. The proof of the finite model property forBCIW, which is equal to the relevant logicR , was originally given by the first author in his unpublished paper [6] in 1973. The finite model property forBCK can be obtained by modifying the proof of that forBCIW. Here, both of these proofs will be given in a unified form and the difference between them will be clarified. Further discussions will be given in the last section.The first author wishes to thank IIAS-SIS (Fujitsu Laboratories Ltd., Numazu) for 9 months hospitality in Japan, and for facilitating this research.Presented byJan Zygmunt     

Occlusion as a depth cue in the Wheatstone-Panum limiting case

We examined the hypothesis (Ono & Wade, 1985) that occlusion of far stimuli by a near one on the same visual line can operate as a depth cue in stereograms containing different numbers of targets in the two eyes. By controlling eye positions, we created conditions in which the visual system could interpret the retinal images as originating from stimuli on the visual axis of one eye and also created other conditions in which the origin of the retinal images was ambiguous. In Experiment 1, we presented two lines to one eye and a single line to the other eye. When the image of the line on the temporal side of the line pair on one retina fused with the image of the single line on the other retina, the nonfused line appeared farther away more often than it did when the image on the nasal side fused. In Experiment 2, we used two differently shaped stimuli. In the condition in which the nonfused stimulus represented an object being occluded, it appeared farther away more often than in the four conditions in which it did not. In Experiment 3, we extended the idea to three different objects. When the middle of the three images fused with the single image, the nonfused stimulus appeared farther when it could be interpreted as being occluded than when it could not. In the condition in which the most temporal image fused with the single image, the nonfused stimuli appeared farther than in the condition in which the most nasal one fused. The results supported the hypothesis that occlusion plays a role in depth perception in the Wheatstone-Panum limiting case.     

The interaction of perceived distance with the perceived direction of visual motion during movements of the eyes and the head

A horizontally moving target was followed by rotation of the eyes alone or by a lateral movement of the head. These movements resulted in the retinal displacement of a vertically moving target from its perceived path, the amplitude of which was determined by the phase and amplitude of the object motion and of the eye or head movements. In two experiments, we tested the prediction from our model of spatial motion (Swanston, Wade, & Day, 1987) that perceived distance interacts with compensation for head movements, but not with compensation-for eye movements with respect to a stationary head. In both experiments, when the vertically moving target was seen at a distance different from its physical distance, its perceived path was displaced relative to that seen when there was no error in pereived distance, or when it was pursued by eye movements alone. In a third experiment, simultaneous measurements of eye and head position during lateral head movements showed that errors in fixation were not sufficient to require modification of the retinal paths determined by the geometry of the observation conditions in Experiments 1 and 2.