The purpose of this study is to examine word recognition processes for logographic Kanji and Kana. Words were printed in written common Kanji jukugo (two-Kanji-compound word) and transcribed in Kana. Two experiments investigated effects of orthographic difference between Kanji and Kana. It was tested whether or not the naming latencies and lexical decision time for Kanji is different with that for Kana. In the first experiment, the naming latencies for Kanji were longer than those for Kana. Specifically, the naming latencies for 2+1 syllable (HAKU) Kanji was more facilitated than those of 1+1 syllable (HAKU) Kanji. The second experiment was enforced to clarify the lexical process by using the lexical decision task. The lexical decision time for Kanji was faster than that for Kana. The lexical decision time of 2+1 syllable (HAKU) Kanji was also more facilitated than those of 1+1 syllable (HAKU) Kanji. The data suggest that the reading of Kanji jukugo is meadiated by a lexical process as well as by a phonological process centering on the first Kanji.

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Two experiments are reported which investigated nature of recognition of natural objects. Stimuli materials were butterfly and bee photographs. Each five features of original pictures were changed to generate changed pictures. In Experiment 1, subjects were given the recognition memory task while the FRS (the sum of feature frequency in the stimuli set) and the component frequency of each feature were kept constant. The experiment was conducted about butterfly and bee pictures separately. Contribution of each feature affected recognition differently. In experiment 2, subjects were given the same task about butterfly pictures as in experiment 1 while similarity ratings between the original and the changed pictures were kept constant. Again contribution of each feature affected recognition differently. These findings suggest that contribution of each feature of natural objects towards recognition is different, and features which contributed highly towards recognition are ecologically meaningful.

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Fuzzy theory provides a computational framework for dealing with fuzziness of human cognition and behavior. Most of psychological researches have been focused on fuzzy set theory, and only a few researches have used fuzzy reasoning for psychological study. However, since fuzzy reasoning represents human decision making processes by fuzzy production rules, fuzzy reasoning must be very useful to model human decision making processes. The present paper exemplifies the applications of fuzzy reasoning to psychological study, and discusses the implication and the applicability of fuzzy reasoning for modeling human decision making processes and supporting human decision making.

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This paper summarized the findings obtained by reexamination of the early Ganzfeld experiments, with special interests in the dynamic relation between 'external world' and 'self'. Subjects were exposed to chromatic Ganzfeld (red, green, blue) and required to give verbal reoports on their experiences. Fade-out and desaturation were remarkable for red-light condition, as compared with green and blue conditions. Interestingly, in the red condition, a typical sequence of phenomena occurred as for the spatiality. Solid concave surface of the screen soon became ambiguous, and the surfaceness was lost, where subjects gave their impression as "something red" and the like. The "something" approached them, came to contact with their eyes, and finally got into their head. At this stage, boudary between 'external world' and 'self' (internal world) was lost. Subjects were not sure of their perception, which was expessed like "not confident of looking out at the world" or "no feeling of being surrounded by external world". Also, concurrent state of perception and emotion was experienced in this situation. Subjects frequently reported "fear of being invaded by something" or "disgust of being touched by red". It indicates pre-differentiation of perception from emotion, and these findings lead us to an approach to the underlying mechanism of spatial phobia.

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The deteriorative effects of hypobaric hypoxia on psychological processing in humans were studied using Questionnaire for High Altitude Symptoms, group judgement test, rote memorization test, Kyoto University Intelligence Test, and cognitive performance task undervarious simulated high altitudes. Most subjects exhibited a syndrome similar to "mountain sickness" during rapid ascent and indicated abrupt impairement of psychological activities at an altitude of 5,000m. Furthermore, the effects of hypobaric hypoxia on cognitive processing were investigated by recording event-related brain potentials (ERPSs) in an odd-ball reaction time (RT) paradigm. Most subjects demonstrared abrupt impairment of RT at high altitudes. RTs lengthened in association with changes in latency and amplitude of the N2-P3 components, reflecting stimulus discrimination and evaluation processes. Slow waves following the P3 component were associated with attempts to maintain RTs against the deteriorative effects of hypobaric hypoxia.

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How human beings achieve visual stability during body movements in space was investigated. When humans are exposed to an environment with different gravity environment, the pre-programmed behavior on the ground must be changed and should be re-programmed. This is habituation or familiarization. Present experiment focuses on visual, vestibular and somatosensory perception coordination and how it changes in microgravity as compared to a 1-G environmeny. We examined these issues under the microgravity during the mission Spacelab Japan (SL-J) mission with the cooperation of the Japanese Payload Specialist (RS), Dr. Mohri. In this paper we describe how the first human life science experiments were conducted and showed the unusual muscie cooperation between gravity specific and non-gravity specific muscle over the mission days.

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