Binocular single vision achieved by fusion and suppression

The occurrences of fusion and suppression were determined from stereograms which produced two retinal images located at equal distances but in opposite directions from the fovea. Subjects reported whether the dichoptic stimulus appeared single or not, and if single whether it appeared in the center of the visual field. The report of centrality is predicted by the fusion theory of single vision and that of noncentrality by the suppression theory. Experiment 1, with eight subjects, showed that for small disparities perceived singleness was the percept predicted by the fusion theory; for larger disparities, the percepts could sometimes be predicted by the fusion theory and other times by the suppression theory. Experiment 2, with 16 subjects, showed that with larger stimuli the percept predicted by the fusion theory is more likely to occur. Experiment 3, with four subjects, showed that the centrality was reported when the stimuli were presented for 100 msec. This result provided support for our interpretation that the centrality reports in Experiments 1 and 2 were not due to fixation error and suppression.     

The cyclopean eye vs. the sighting-dominant eye as the center of visual direction

In three experiments, competing hypotheses concerning the center of visual direction were examined with the stimuli used in the Card test which requires a subject to position the card with a hole so that a target can be seen. Each experiment used six right- and six left-sighting-eye subjects. In Experiment 1, the aperture and the target were collinear with the sighting eye. The mean apparent locations of the aperture when the target was fixated, and of the target when the aperture was fixated, were consistent with only the cyclopean-eye hypothesis; that is, the 95% confidence intervals of these means contained the predicted values from the cyclopean-eye hypothesis but not those from the sighting-eye hypothesis. In Experiment 2, subjects moved the card from the side of the nonsighting eye, and in 88% of the trials it was stopped when the nonsighting eye viewed the target. In Experiment 3, the target was viewed through the aperture with both the sighting and nonsighting eye in six different stimulus arrangements. The 95% confidence intervals of all 12 mean apparent locations of the targets contained the predicted values from the cyclopean-eye hypothesis but none of those from the sighting-eye hypothesis. These results are compatible with the cyclopean-eye hypothesis, and we therefore conclude that the sighting eye is not the center of visual direction.     

Oculomotor adjustments and size-distance perception

The relationship between perceived size and distance and oculomotor adjustments were assessed in two experiments. In both experiments, Ss were required to make scalar linear size, angular size, and distance judgments of stimuli subtending a constant retinal image size at different levels of convergence. The results of the first experiment indicate that the perceived linear size, angular size, and distance of the stimulus decreased with increased convergence, the decrease in perceived linear size being greater than that of perceived angular size. While again showing a decrease in perceived linear and angular size, the results of the second experiment also show that there was a smaller decrease in perceived distance with increased convergence when Ss continued to view the stimulus as convergence was changed than when they did not view the stimulus as convergence was changed. The implications these results have for size and distance perception are discussed.     

On-line and off-line reflexive resolution in Japanese logophoric sentences

This study investigates on-line and off-line resolution of a Japanese reflexive,jibun, for logophoric sentences, i.e., complex sentences involving a matrix verb that reflects one's point of view feelings, or state of consciousness, and for nonlogophoric sentences, i.e., complex sentences involving a subordinate adverbial clause. According to Kuroda's (1973) thesis and Chomsky's (1981) binding principle (for nonlogophoric sentences only), the reflexive in the logophoric sentences can be associated with the subject of both a matrix sentence and a subordinate sentence whereas that in the nonlogophoric sentences can only be associated with the subject of the subordinate sentence. In Experiment 1, 42 students were administered a probe-recognition task in which a probe was given for the subject either of the matrix sentence or of the subordinate sentence immediately after the end of the subordinate clause or at the end of a sentence following the matrix verb. Recognition times were faster for a matrix-subject probe than for a subordinatesubject probe regardless of the sentence type and probe position. In Experiment 2, 40 students were administered an on-line antecedent identification task in which they were required to quickly and accurately identify, when given a probe, the antecedent of the reflexive, with the probe given after the reflexive or at the end of a sentence. Regardless of the sentence type, matrix-subject was judged to be the antecedent of the reflexive more often than subordinate-subject, with the effect of probe position being negligible. An offline study required 136 students to indicate the antecedent(s) for the two types of sentence given in their entirety. No effect of sentence type was found. Findings indicate that neither Kuroda's thesis nor Chomsky's binding principle is applied when Japanese speakers parse logophoric and nonlogophoric sentences.Part of this study was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture, No. 05610067. Deep gratitude is due to Professor D. D. Steinberg for reading an earlier version of this paper. Thanks are also due to Ms. S. Ogawa for her help in collecting part of the off-line data.     

How do Rumination and Social Problem Solving Intensify Depression? A Longitudinal Study

In order to examine how rumination and social problem solving intensify depression, the present study investigated longitudinal associations among each dimension of rumination and social problem solving and evaluated aspects of these constructs that predicted subsequent depression. A three-wave longitudinal study, with an interval of 4 weeks between waves, was conducted. Japanese university students completed the Beck Depression Inventory-Second Edition, Ruminative Responses Scale, Social Problem-Solving Inventory-Revised Short Version, and Interpersonal Stress Event Scale on three occasions 4 weeks apart (n = 284 at Time 1, 198 at Time 2, 165 at Time 3). Linear mixed models were analyzed to test whether each variable predicted subsequent depression, rumination, and each dimension of social problem solving. Rumination and negative problem orientation demonstrated a mutually enhancing relationship. Because these two variables were not associated with interpersonal conflict during the subsequent 4 weeks, rumination and negative problem orientation appear to strengthen each other without environmental change. Rumination and impulsivity/carelessness style were associated with subsequent depressive symptoms, after controlling for the effect of initial depression. Because rumination and impulsivity/carelessness style were not concurrently and longitudinally associated with each other, rumination and impulsive/careless problem solving style appear to be independent processes that serve to intensify depression.     

A paper-format group performance test for measuring the implicit association of target concepts

We developed a paper test utilizing a mechanism for measuring implicit association similar to that used in the Implicit Association Test (IAT; Greenwald, McGhee, & Schwartz, 1998). The target concepts were buried among positive and negative words on a piece of paper. Examinees marked the targets as "bad" or "good" in one task and conversely in the other, along with the evaluative words. Instead of reaction times, we counted the number of words marked in 20 sec for each task. This procedure allowed group administration. We calculated the implicit measure using the difference in the average number of words marked in the task pairs. The results of a test administered to 82 undergraduates with three different targets showed significant correlations (rs = .26-.35) with the results of IAT administered to the same participants. It also showed significant reliability (rs = .56-.71). We discuss the practical usability of the test with application studies conducted in various areas.     

The relationship between masculinity and the Type A behavior pattern: the moderating effects of femininity

The purpose of the study was to examine whether a high level of masculinity is associated with the Type A behavior pattern, and whether the level of femininity moderates any main effect for masculinity. The subjects were 743 male and 560 female undergraduate students. In the statistical analysis, we found evidence of the masculinity effect on every Type A score, and a moderating effect of femininity on the “speed‐power” subscale score. We discuss the validity of four models of the functions of masculinity and femininity, and consider the moderating effect of femininity in the light of the interactive androgyny model.     

Contrast effect in evaluating palatability of beverages.

This study aimed to clarify the contextual effect in evaluation of the pleasantness of beverages. Participants were presented a test stimulus and were then asked to rate how much they liked it before and after presentation of a contextual stimulus. Specifically, after participants were exposed to a less palatable beverage, they evaluated the test beverage as being more palatable than when their judgment of a test drink occurred after presentation of a neutral or palatable beverage (a positive contrast effect). This contextual effect can be explained by the reasoning that participants were affectively adapted to the palatability (less palatable) of a less palatable stimulus after repeated exposure; thus, they evaluated the test stimulus as more palatable. This study suggests that the evaluated value of the contextual stimuli affects evaluation of the test stimulus. The authors also suggest that these context effects are probably found in everyday life.     

Neuromagnetic signals associated with reading a kanji character formed by combining two kanji radicals

To find out which brain regions are responsible for the mental construction and recognition of a kanji character initiated by visually presented kanji radicals, rather than by information retained in the memory, a left hen radical and the corresponding right tsukuri radical were simultaneously presented randomly to either the left or right visual field of seven subjects. Thirty left hen radicals and the corresponding right tsukuri radicals were prepared as stimuli; this combination formed over 500 real or pseudo kanji characters. Instead of their usual left and right positions, the left hen radical was always presented above the right tsukuri radical. As quickly and correctly as possible, the subjects released a key when two kanji radicals constituted a single real kanji character and released another key otherwise. We recorded neuromagnetic responses as well as accuracy and reaction time. Left visual field superiority was observed as regards accuracy. This is in good agreement with previous neuropsychological results. Equivalent current dipoles were localized mainly in the left and/or right occipitotemporal regions (ventral visual pathways), the bilateral occipitoparietal regions (dorsal visual pathways) including the supramarginal region, and the areas surrounding the left superior temporal cortex. We suggest that these regions are related to reading and the mental construction of a kanji character from its radicals.     

Neural correlates for learning to read Roman numerals

This study examined the neuronal correlates of reading Roman numerals and the changes that occur with extensive practice. Subjects were scanned by functional Magnetic Resonance Imaging (fMRI) three times the first day of the experiment and once following two to three months of practice. This allowed comparison of brain activations with varying levels of practice on the same day and across the two to three months of training. The results revealed that upon learning that the alphabetical symbols had numeric meaning subjects immediately activated a network of brain areas, many of which have been previously implicated in numerical processing. Subsequent practice led to a change in the pattern of neuronal activity in only a single region of the mid-dorsolateral prefrontal cortex in the left hemisphere. Implications of these findings are argued with regard to the prevalent neuronal model for the implementation of elementary numerical abilities.