Monocular without stereopsis with and head movement

Random dots moving with various velocity gradients were presented to observers; the motion was yoked to head movement in one condition and to no head movement in another. In Experiment 1, 12 observers were shown motion gradients with sine, triangle, sawtooth, and square waveforms with amplitudes (equivalent disparities) of 12′ and 1° 53′. In Experiment 2, 48 observers were shown only the sinewave or square-wave gradient of 1° 53′ disparity either with or without head movement so that the observers’ expectation to see depth in one condition did not transfer to another. The main findings were: (1) with 12′ disparity, the head-movement condition produced perceived depth but almost no perceived motion, whereas the no-head-movement condition produced both perceived depth and perceived motion; (2) with 1° 53′ disparity, both conditions produced perceived depth and perceived motion; and (3) when the expectation to see depth was removed, the no-head-movement condition with the square-wave gradient produced no perceived depth, only motion. We suggest that monocular stereopsis with head movement can be achieved without perception of motion but monocular stereopsis without head movement requires perception of motion.     

Visual information for categorizing facial expression of emotions

Two experiments were conducted to reveal the visual information from the face utilized for the categorization of its expression of emotions. In Experiment 1 the subjects produced six schematic faces expressing six basic emotions by using a computer graphics system. By a series of factor analyses on the variables of displacements of feature points for deforming a neutral schematic face to produce the six expressional ones, two factors of ‘curvedness/openness’ and ‘slantedness’ of facial elements were obtained. In Experiment 2 another group of subjects made category judgements of emotions for 72 of the total 216 schematic faces produced in Experiment 1. The relationship between the displacements of feature points in Experiment 1 and subjects' categorical responses in Experiment 2 were examined by canonical discriminant analysis. It was found that the categorical judgements were well explained by two canonical variables whose structures were quite similar to those of factors obtained in Experiment 1. These results indicated that we extract the information of changes in curvedness/openness and slantedness of facial elements among other information on the face for categorizing its expressions of emotions. Lastly, the relationship between the dimensions of visual information obtained here and those of semantic affective meanings found in earlier research was discussed.     

A marginalization model for the multidimensional unfolding analysis of ranking data

A marginalization model for the multidimensional unfolding analysis of ranking data is presented. A subject samples one of a number of random points that are multivariate normally distributed. The subject perceives the distances from the point to all the stimulus points fixed in the same multidimensional space. The distances are error perturbed in this perception process. He/she produces a ranking dependent on these error-perturbed distances. The marginal probability of a ranking is obtained according to this ranking model and by integrating out the subject (ideal point) parameters, assuming the above distribution. One advantage of the model is that the individual differences are captured using the posterior probabilities of subject points. Three sets of ranking data are analyzed by the model.     

Fixation disengagement and eye-movement latency

We examined eye-movement latencies to a target that appeared during visual fixation of a stationary stimulus, a moving stimulus, or an extrafoveal stimulus. The stimulus at fixation was turned off either before target onset (gap condition) or after target onset (overlap condition). Consistent with previous research, saccadic latencies were shorter in gap conditions than they were in overlap conditions (the gap effect). In Experiment 1, a gap effect was observed for vergence eye movements. In Experiment 2, a gap effect was observed for saccades directed at a target that appeared during visual pursuit of a moving stimulus. In Experiment 3, a gap effect was observed for saccades directed at a target that appeared during extrafoveal fixation. The present results extend reports of the gap effect for saccadic shifts during visual fixation to (a) vergence shifts during visual fixation, (b) saccadic shifts during smooth visual pursuit, and (c) saccadic shifts during extrafoveal fixation. The present findings are discussed with respect to the incompatible goals of fixation-locking and fixation-shifting oculomotor responses.     

Effectiveness of word order and grammatical marker as syntactic indicators of semantic relations

The effectiveness of word order and grammatical markers as syntactic indicators of semantic relations was explored using an artificial linguistic system. The results showed: (1) semantic interpretation of novel sentences was possible not only for Ss given fixed word order sentences with or without the markers, but also for Ss given the markers in random word order sentences; (2) Ss given neither indicator showed chance performance; (3) word order tended to be more efficient than grammatical markers as clues to semantic relations. The results suggest that the critical condition for language acquisition is the constant covariation of linguistic structure with semantic contexts. A process approach is discussed in accounting for the findings.Half of the data of the present experiment (FP and FA) were collected by Miss Norie Wake for her BA thesis, Okayama University (1978). The other half (RP and RA) were collected by the three juniors for their advanced course of experimental psychology, Okayama University (1979).     

Temporal course of activation of the antecedent by the reflexive in syntactically ambiguous sentences in Japanese

Three experiments examined the temporal course of the activation of an antecedent triggered by a reflexive,jibun, in syntactically ambiguous sentences in Japanese. Twenty-two students in Experiment 1 were tested for sentences where a subject word occupied the first position and an indirect object word the second, with the probe given for each word either immediately after the reflexive or at the end of the sentence. Reaction times (RTs) were faster when the probe was for subject (S-probe) than when it was for indirect object (IO-probe) irrespective of the probe position. Experiment 2 tested 22 students to determine the effect of order of mention of participant on the probe recognition time. RTs were faster for the S-probe than for the IO-probe, although the difference between the two probes was smaller when the probe was given immediately after the reflexive. Experiment 3 tested 22 students to examine the effect of context on an activation pattern. RTs were lower for the S-probe than for the IO-probe, though no difference was found between them for the probe given at the end of the sentence. Findings were interpreted as supporting the single-interpretation model for on-line analysis of syntactically ambiguous sentences and also the immediate-activation model in an assignment of the reflexive to its antecedent.     

Four methods of locating the egocenter: A comparison of their predictive validities and reliabilities

An attempt was made to identify the best method of locating the egocenter by comparing the predictive validity and reliability of the four methods introduced by Fry (1950), Funaishi (1926), Howard and Templeton (1966), and Roelofs (1959). To determine predictive validity, egocenters located by these methods were used to predict the responses of 14 subjects on three visual direction tasks; the correlation between the predicted and the actual responses on each task was computed. To determine reliability, the test-retest stability and the internal consistency were estimated for each method. All of the methods were reliable, but only the Howard and Templeton method predicted the results on all three of the visual direction tasks. The high reliability and predictive validity of the Howard and Templeton method is attributed to its high precision.     

Assessing Representations of Close Relationships Among Chinese and Japanese Adolescents and Young Adults: Commonalities and Differences in the Two Confucian Cultures

This article proposed an affective relationships model with its assessment instrument and examined how Chinese and Japanese adolescents and young adults construct mental representations of their close relationships, and the influence of Confucian cultural beliefs on these representations. The participants were 1,565 students aged 14 to 24 years living in China or Japan. The students were asked about their relationships with four figures: mother, father, closest friend, and romantic partner. We found that: (a) adolescents and young adults in both cultures constructed constellations of relationships containing multiple figures, and they articulated reasons for each figure's significance; and (b) there were between-group differences in the relationships with the father and the romantic partner for Chinese versus Japanese adolescents and young adults. These differences were partly explained by the influence of Confucianism on the Chinese participants’ cultural beliefs that retained the patriarchal values.     

Age-related EMG variables during maximum voluntary contraction

We studied the neuromuscular adaptation that occurs with aging by comparing changes in surface electromyography (EMG) variables from the tibialis anterior muscle in 12 young (21.4 +/- 1.7 yr. old) and 13 older subjects (70.8 +/- 3.1 yr. old). EMG variables such as the muscle fiber conduction velocity, median frequency, and averaged rectified value were calculated during maximum voluntary contraction for 5-sec. isometric contractions. The dorsiflexion force, muscle fiber conduction velocity, median frequency, and average rectified value during maximum voluntary contraction were significantly smaller in the older than in the younger group (p < .05). These results suggested that the neuromuscular system in older subjects is affected by the selective atrophy of fast twitch fibers and differences in motor unit firing statistics. Our results suggest the utility of applying the EMG observed during maximum voluntary contraction to the noninvasive evaluation of neuromuscular function in elderly persons.     

The pursuit of Leonardo's constraint

Leonardo da Vinci (1452-1519) identified two stimulus situations that cannot be painted faithfully on a canvas: (a) when two objects are located in the same direction with respect to the painter's head, and (b) when parts of a surface are visible to one eye, but occluded from the other eye. He analysed these situations in terms of rays being emitted from the two eyes and, aside from the origin of the rays, the projective geometry he used was correct. His analyses showed that what can be seen from two vantage points cannot be represented on a canvas, because a 'correct' painting must be created from a single 'station point'. He was struck by the consequence of this fact that the depth seen on a canvas cannot match that of viewing the scene with two eyes. Subsequent visual scientists focused on Leonardo's observation about the lack of vivid depth in a picture. We argue that a complete understanding of what we see in the two stimulus situations requires consideration of visual direction in addition to visual depth. More specifically, we argue that the visual directions of the two objects, (a) above, and the visual direction of the monocular areas, (b) above, are dependent upon the constraint that two opaque objects cannot be represented in the same direction. Demonstrations that readers can perform, and that support this argument, are provided on the Perception website at http://www.perceptionweb.com/perc0102/ono.html.