Effects of sine wave combinations on the development of precognitive mode in pursuit tracking

A pursuit tracking task was carried out to investigate the effects of combinations of sine waves on the development of precognitive mode, which is defined as open-loop mode with little feedback. Subjects were asked to track the targets, which contained two or three sine waves as components, and then to reproduce the target motion after the target had been removed. Frequency characteristics of tracking revealed the superiority of the faster component over the slower components in terms of both amplitude ratio and tracking lag. Subjects' reproduction after removing the target demonstrated that in general, subjects could learn and memorize also the slower component motion, which had yielded inferior performance during the tracking period. These results are discussed in terms of a model based on successive organization of perception.     

The Effects of Word-Order and Case Marking Information on the Processing of Japanese

Many studies in processing English report that verb information plays a significant role in processing the rest of the sentence (e.g., Boland & Tanenhaus, 1991). Japanese is subject-object-verb (SOV), head-final language with the phenomena of scrambling and phonologically null pronouns. The fact that verb information does not become available until the end of a clause leads one to ask whether other types of information may be utilized in the on-line processing of Japanese. The current study investigated whether word order and case markers play a role. Overall, no effect of word order was observed, even though the frequency of the scrambled sentences was low. Experiment 1 found no extra processing load in processing scrambled sentences. In Experiment 2, no effect of word order was found in the parser's decision making in computing a syntactic structure prior to the verb. On the other hand. Experiment 3 found that the parser was sensitive to the variety of case-marked arguments. The results of the three experiments are more congruent with the nonconfigurational structure than with the configurational structure at the stage of preverbal syntactic processing in Japanese.     

Intermanual differences on neuropsychological motor tasks in a Japanese university student sample

We explored the intermanual difference scores of 128 Japanese university students for five typical neuropsychological motor tasks (grip strength, finger tapping, two versions of the grooved pegboard, and the dot‐filling test) and examined the relation between hand preference and intermanual difference in motor proficiency. Using the Edinburgh Handedness Inventory, 18 and 110 participants were identified as left‐ and right‐handed, respectively. Although the right hand performed better than the left for right‐handed participants, and vice versa, in all five tasks, the degree of intermanual difference varied between tasks. A discriminant function analysis using the laterality quotients of the five motor tasks as independent variables indicated that hand preference was predictable from the task performances with an accuracy of 90% or more. The dot‐filling test and finger tapping had stronger canonical loadings than the other tasks.     

Tilted InSb nanostructures fabricated by off-normal ion beam irradiation

ABSTRACT

Using a two-step focused ion beam irradiation process, tilted InSb nanostructures have been fabricated using a off-normal angle of irradiation. In the first step, a well-focused ion beam was used to irradiate the surface of the structure to achieve top-down sputtering. In the second step, the ion beam was used to irradiate the entire surface to promote bottom-up nanostructure growth through the migration of ion-beam-induced interstitial atoms. The formation of a nanostructure with a 46° tilt and an aspect ratio of 0.5 was achieved using ion beam irradiation at an angle of 45° in both steps of the process. The 2% concentration of point defects obtained by changing the volume of the nanostructure before and after irradiation contributed to the growth of the structure. The results showed that many point defects did not recombine, and survived to contribute toward the growth of the wall structure.     

The fate of originally presented surface information following recall errors in sentence memory tasks

Pictures are remembered better than their names. This picture superiority effect in episodic memory has been attributed either to the greater sensory distinctiveness of pictures or to their greater conceptual distinctiveness. Weldon and Coyote (1996) tested the conceptual distinctiveness hypothesis by comparing how well pictures as opposed to words primed in two conceptual implicit memory tasks (category production and word association). They found no picture superiority in priming and concluded that the basis of the picture superiority effect must then be pictures' greater sensory distinctiveness. Using the same logic, we compared how well pictures as opposed to words primed in a perceptual implicit memory task (picture and word fragment identification). The sensory distinctiveness theory would predict that pictures should prime picture fragment identification better than words prime word fragment identification, a result we call the picture superiority in within-form priming. Across three experiments which manipulated the encoding task at study, only one showed picture superiority in within-form priming. In contrast, in all three experiments there was robust picture superiority in recall, and exposure to pictures and words at study and test produced independent effects in which both study and test exposure to pictures was more effective for recall than exposure to words. We consider how these results might be reconciled by differences in retrieval demands between recall and fragment identification.     

Pursuit eye movement in tracking a target with two sine waves

It has been reported that, when subjects track a moving target comprising two sine waves, the tracking lag for the faster sine wave component is much smaller than that for the slower one. To understand this phenomenon further, this study examined frequency characteristics of the human tracking response and pursuit eye movement in response to the target with two sine waves of equal amplitude. Analysis indicates that, while the tracking response has very large phase lag for the slower sine wave component and very small phase lag for the faster one, the pursuit eye movement has a conspicuously large phase lead for the slower component and very small phase lag for the faster one. It is suggested that the lack of synchrony of the pursuit eye movement with slower component of the target may be associated with the inferiority of the slower component to the faster one in tracking lag.     

Stimulus selectivity of figural aftereffects for faces

Viewing a distorted face induces large aftereffects in the appearance of an undistorted face. The authors examined the processes underlying this adaptation by comparing how selective the aftereffects are for different dimensions of the images including size, spatial frequency content, contrast, and color. Face aftereffects had weaker selectivity for changes in the size, contrast, or color of the images and stronger selectivity for changes in contrast polarity or spatial frequency. This pattern could arise if the adaptation is contingent on the perceived similarity of the stimuli as faces. Consistent with this, changing contrast polarity or spatial frequency had larger effects on the perceived identity of a face, and aftereffects were also selective for different individual faces. These results suggest that part of the sensitivity changes underlying the adaptation may arise at visual levels closely associated with the representation of faces.     

"Long before short" preference in the production of a head-final language

A tendency for speakers to produce short phrases before long phrases has been attributed to the accessibility of short phrases, and thought to reflect universal mechanisms of production. However, recent corpus analyses in Japanese suggest that long phrases tend to be shifted ahead of short ones (Hawkins, J. (1994). A performance theory of order and constituency. Cambridge: Cambridge University Press; Yamashita, in press). Two on-line experiments confirmed that speakers shifted long arguments to earlier positions more than short arguments, exhibiting a "long before short" preference. We reconcile these contradictory data from English and Japanese by a competition between different factors in an incremental production system.     

Tolerance of geometric distortions in infant's face recognition

The aim of the current study is to reveal the effect of global linear transformations (shearing, horizontal stretching, and vertical stretching) on the recognition of familiar faces (e.g., a mother's face) in 6- to 7-month-old infants. In this experiment, we applied the global linear transformations to both the infants’ own mother's face and to a stranger's face, and we tested infants’ preference between these faces. We found that only 7-month-old infants maintained preference for their own mother's face during the presentation of vertical stretching, while the preference for the mother's face disappeared during the presentation of shearing or horizontal stretching. These findings suggest that 7-month-old infants might not recognize faces based on calculating the absolute distance between facial features, and that the vertical dimension of facial features might be more related to infants’ face recognition rather than the horizontal dimension.     

What to copy: the key factor of observational learning in striped jack (Pseudocaranx dentex) juveniles

Animals in social environments can enhance their learning efficiency by observing the behaviour of others. Our previous study showed that learning efficiency of schooling fish increased through the observation of the behaviour of trained demonstrator conspecifics. The present study aimed to verify the key factor of observational learning by investigating what information is important for social transmission of feeding information. A striped jack (Pseudocaranx dentex) observer was provided with one of the five observation treatments: (a) pellets observation, where pellets were dropped near the aeration in an adjacent tank; (b) responding conspecific observation, where a trained conspecific demonstrator responded to the aeration without food in the adjacent tank; (c) foraging conspecific observation, where a conspecific demonstrator foraged near the aeration in the adjacent tank; (d) nearby pellets observation, where pellets were dropped in a transparent column near the aeration in the observer tank; and (e) foraging heterospecific observation, where a filefish (Stephanolepis cirrhifer) demonstrator foraged near the aeration in the adjacent tank. The response to the aeration in these observers was compared with that of controls who did not observe any behaviour. Only individuals who observed foraging conspecifics showed a response to the aeration after observing. These results suggest that observer fish acquire feeding information not through recognition of prey items or through imitation of the demonstrator, but through the vicarious reinforcement of a conspecific for foraging.