Perceptual grouping in pigeons

Animal studies reveal that many species perceive partially occluded objects in the same way as do humans. Pigeons have been a notable exception. We re-investigated this anomaly of pigeon perception using a different approach from previous studies. With our method, we show that pigeons perceive occluded objects in the same manner as do other species. In addition, we report that pigeons can recognize perceptually transparent surfaces when the effect is induced by the same perceptual mechanisms as occlusion. These results give behavioral evidence that the perception of both occlusion and transparency is a common visual function shared by pigeons and humans, despite the structural differences between their visual systems.     

A Generalized Syllogistic Inference System based on Inclusion and Exclusion Relations

We introduce a simple inference system based on two primitive relations between terms, namely, inclusion and exclusion relations. We present a normalization theorem, and then provide a characterization of the structure of normal proofs. Based on this, inferences in a syllogistic fragment of natural language are reconstructed within our system. We also show that our system can be embedded into a fragment of propositional minimal logic.     

Temporal reticence of the self: who can know <Emphasis Type="Italic">my self</Emphasis>?

In this study, I will elaborate and extend the theoretical framework of the presentational self (Komatsu, Human Development 53:208–228, 2010) that finds the self in two aspects of our interaction with others or objects. From this perspective, the self is not an internal entity, a representation that can be revealed voluntarily when directly queried by researchers (e.g., through items of a questionnaire or an interview), but is what emerges from constantly relating with the immediate environment. The process structure of being in the environment that emerges in this relationship is the presentational self, which both an external observer and the person him/herself can detect but not necessarily describe in words. For further elaboration, first, I clarify that the triangular relationship between a study participant, others or objects, and observing researchers, which is essential in the presentational self, is also common in the methodological presuppositions of existing psychological studies on the self. Second, I apply the framework to a daily activity of oral storytelling in a Japanese elementary school, where the emergence of children’s self is observable through sequences of organized interactions with others. From these discussions, I demonstrate both the theoretical and practical importance of considering the self to refer to the relationships that we constantly create in our daily life.     

Processes of Social Influence on Sampling Behavior: The Effect of Other's Positive Attitude and Receiver's Prior Experience

Studies about attitude formation have pointed out the importance of sampling behavior. When thinking about actual social interaction scenes, it may be better to consider them as attitude-updating processes between those who have already formed attitudes based on some experience. Sixty-five participants took part in the experiment, in which the other's positive attitude and the participant's own prior experience were manipulated. After participants had been presented five types of puzzles (experience: direct vs. indirect), which had been made to improve analytic ability, their attitudes towards the puzzles were measured (“pre attitude”). They were shown the other's positive attitude (inconsistent vs. consistent), and they were given 10 min of free time before “testing on their analytic ability.” The amount of time spent on each puzzle was recorded to index sampling behavior and the attitudes towards the puzzles were measured after the free time (“post attitude”). The results of analyses showed that the other's positive attitude increased sampling behavior when the participant's attitude was positive (first-ranked) and negative (fifth-ranked), and that prior experience and sampling contributed to attitude change for the first-ranked puzzle. Those who had had direct experience and those who had spent more time sampling this puzzle tended to maintain their previous positive attitude. The potential boundary conditions of social influence on sampling behavior are discussed.     

How Signs Function in the Process of Meaning Construction: An Exemplification from <Emphasis Type="Italic">Gitai-go</Emphasis> in the Japanese Language

In this paper, I will examine the semiotic mediation process of meaning construction and the functioning of signs, focusing on a group of characteristic words, Gitai-go in the Japanese language. Mimic words in the Japanese language, including Gitai-go are applicable to various subjects based on their inter-sensory nature, and appear frequently in informal communication among Japanese, not only for young children but also in adults’ communication. When I consider their functioning from the viewpoint of meaning construction, their characteristic feature is their indefiniteness that is open to diverse forms of extension, including that of no further elaboration and continuous diffusion of the affective flavor within the current setting. Though the process is interpretable in terms of the Japanese culture that is characterized by vagueness, it is also a clear exemplification of how the indefiniteness of signs works in the process of meaning construction and in our communication.     

The link between involuntary non-regular employment and poor mental health: A cross-sectional study of Japanese workers

Involuntary non-regular employment is a severe inequity problem worldwide, and it may significantly affect the mental health of employees. The present study aimed to examine the relationship between employment type and mental health. Additionally, the characteristics of involuntary non-regularly employed workers were explored. An online-based cross-sectional study was conducted in Japan, and 1566 participants were included in the data analysis. The eligible participants were divided into four categories: regularly employed (n = 1092), voluntary (n = 134), average (n = 233) and involuntary (n = 107) non-regularly employed individuals, respectively. Involuntary non-regular employment was associated with greater lack of vigour, anger-irritability, fatigue, anxiety, and depression. It was higher among women, those who were single or had no childcare, and those who had lower personal income or shorter working hours, or who tended not to practice relaxation activities. Lower personal income was associated with a risk of anxiety and depressive symptoms. Those individuals experiencing involuntary non-regular employment had a higher risk of poor mental health; subgroup analysis showed that this was particularly true among men. Both encouragement of employment stability via policy reform and workplace mental health support for involuntary non-regularly employed individuals are urgent health concerns.     

Not Seeing is Believing: the Role of Invisibility in Human Lives

Our life is full of invisibility that exerts power on our acts, relationships, and construction of the self. This paper discusses psychological processes in which invisibility plays an essential role, and constructs a typology of invisibility in society and in our lives. After a brief look at the crucial role of invisibility in prevailing theories of psychology, I first show how invisibility works in children’s meaning constructions, the process in which their selves become clear for observers (the presentational self, Komatsu 2010). The development of children’s meaning making is led by different types of invisibility concerning the children themselves. Second, I extend the discussion from the development of individuals to the role of socially regulated invisibility that controls our acts and relationships with others, introducing examples concerning religious belief in history. After these discussions, I present a hierarchical classification of invisibility from a simple spatial-temporal separation of concretely existing objects and ourselves to an abstract aspect of invisibility in which the object and its meaning are unclear.     

Evaluation of task performance during mentally imaging three-dimensional shapes from plane figures

Mental imagery is an important theme in psychology. Although the mental rotation task is well known, the complicated functions in mental images with higher spatial perception remain unknown. The aim of this study was to evaluate the task performances during the mental imaging of two- or three-dimensional shapes (14 healthy male students, M age = 24.2 yr., SD = 3.4). The mental-image task to frame a 3D object from actual 2D figures (2D-3D task) had the longest reaction time (p < .01); performance accuracy on this task was lower than for other tasks. The reaction time for the 2D-3D task differed statistically significantly from that on the typical working memory task using the mental image of three 2D figures. Compared with the 2D-3D task, illustration of a simple 3D object would be effective when a quick judgment of high accuracy is required. The feasibility study using an electroencephalogram suggests that the theta-band activity at the middle frontal lobe reflecting the acts of the working memory is related with mental images.     

Comparison between the lambda response of eye-fixation-related potentials and the P100 component of pattern-reversal visual evoked potentials

The purpose of this study was to compare the lambda response of eye-fixation-related potentials (EFRPs) with the P100 component of pattern-reversal visual-evoked potentials. EFRPs were obtained by averaging EEGs time-locked to the offset of the saccade. The dipole of the lambda response and that of the P100 component were estimated by the dipole-tracing method (Musha & Homma, 1990). The locations of their dipoles at the occipital sites were very close to each other when the difference waveform, which was calculated by subtracting the EFRP to the patternless stimulus from the EFRP to the patterned stimulus, was used for the lambda response. This finding implies that the lambda response and P100 have a common neural generator in the visual cortex. However, the peak latency of the lambda response was shorter than that of P100. The saccades in the EFRP trial were considered to be the cause of the difference.