Odd Sensation Induced by Moving-Phantom which Triggers Subconscious Motor Program

Our motor actions are sometimes not properly performed despite our having complete understanding of the environmental situation with a suitable action intention. In most cases, insufficient skill for motor control can explain the improper performance. A notable exception is the action of stepping onto a stopped escalator, which causes clumsy movements accompanied by an odd sensation. Previous studies have examined short-term sensorimotor adaptations to treadmills and moving sleds, but the relationship between the odd sensation and behavioral properties in a real stopped-escalator situation has never been examined. Understanding this unique action-perception linkage would help us to assess the brain function connecting automatic motor controls and the conscious awareness of action. Here we directly pose a question: Does the odd sensation emerge because of the unfamiliar motor behavior itself toward the irregular step-height of a stopped escalator or as a consequence of an automatic habitual motor program cued by the escalator itself. We compared the properties of motor behavior toward a stopped escalator (SE) with those toward moving escalator and toward a wooden stairs (WS) that mimicked the stopped escalator, and analyzed the subjective feeling of the odd sensation in the SE and WS conditions. The results show that moving escalator-specific motor actions emerged after participants had stepped onto the stopped escalator despite their full awareness that it was stopped, as if the motor behavior was guided by a “phantom” of a moving escalator. Additionally, statistical analysis reveals that postural forward sway that occurred after the stepping action is directly linked with the odd sensation. The results suggest a dissociation between conscious awareness and subconscious motor control: the former makes us perfectly aware of the current environmental situation, but the latter automatically emerges as a result of highly habituated visual input no matter how unsuitable the motor control is. This dissociation appears to yield an attribution conflict, resulting in the odd sensation

Failure of Cut-Elimination in the Cyclic Proof System of Bunched Logic with Inductive Propositions

Cyclic proof systems are sequent-calculus style proof systems that allow circular structures representing induction, and they are considered suitable for automated inductive reasoning. However, Kimura et al. have shown that the cyclic proof system for the symbolic heap separation logic does not satisfy the cut-elimination property, one of the most fundamental properties of proof systems. This paper proves that the cyclic proof system for the bunched logic with only nullary inductive predicates does not satisfy the cut-elimination property. It is hard to adapt the existing proof technique chasing contradictory paths in cyclic proofs since the bunched logic contains the structural rules. This paper proposes a new proof technique called proof unrolling. This technique can be adapted to the symbolic heap separation logic, and it shows that the cut-elimination fails even if we restrict the inductive predicates to nullary ones

Application of a truncated distribution for tsumugi yarn width

Hand-spun, silk yarn made from floss silk is referred to as tsumugi yarn. It gives a unique appearance on the products, also called tsumugi, which are considered to be an important type of fabric for their aesthetics. The essential factor of this visual effect is originated by the thickness variation of tsumugi yarn; however, the detail of the variation is unknown. In this paper, as a fundamental study of tsumugi yarn, its width distribution is discussed. To model the width distribution, the Polya-Eggenberger distribution is introduced. Moreover some modifications are applied for the distribution to describe the yarn's situation. That is to say, it is impossible to be thinner than a level of thickness for the yarn to maintain a shape of a thread; on the other hand, tsumugi yarn is not limited to only containing thicker parts. Additionally, it is unavoidable to involve errors and fluctuations in the actual data. Hence, the distribution is truncated and convoluted. By using an image scanner, the width of tsumugi yarn is measured. With the measured data, the parameters of the width distribution are estimated using the maximum likelihood method. The results show that the width distribution of tsumugi yarn is asymmetric and well summarized by the distribution.ArticleTEXTILE RESEARCH JOURNAL. 85(9):929-935 (2015)journal articl