Ascidian tadpole larvae, composed of only about 2500 cells, have a primitive nervous system which is derived from the neural plate. The stereotyped cell cleavage pattern and well characterized cell lineage in these animals allow the isolation and culture of identified blastomeres in variable combinations. Ascidian embryos express cell‐type‐specific markers corresponding to their cell fates, even when cultured under cleavage‐arrest by cytochalasin B. This system provides us with a unique opportunity to study the roles of cell lineage and cell contact (...) in early neuronal differentiation in the absence of events associated with complex morphogenesis. In addition, the isolated, cleavage‐arrested blastomeres are ideally suited to electrical recording, permitting the use of ionic channels as specific markers for differentiation. In the cleavage‐arrested embryos, suppression of one type of K+ channel, and induction of two types of Na+ channels, occur following cell contact with the vegetal blastomere. The combination of molecular and electrophysiological analyses on this simple animal system may provide insights into the nature of the cell interactions important in early neurogenesis, both in ascidians and in vertebrates. (shrink)

Hegel, in his work _Philosophy of Right_, defines ownership through three elements: acquisition by occupation, use, and transfer. To own something involves mere acquisition and encompasses its appropriate use and potential transfer to others. Subsequently, the final aspect mentioned was the concept of infinite judgement. The acts of owning and transferring to others are diametrically opposed, and Hegel’s unique logic forcibly connects these opposing concepts. This form of infinite judgement was advocated by the young Hegel during the era of _Phenomenology (...) of Spirit_. There, he stated, “Spirit is a bone”. However, when he later wrote _Science of Logic_ or _Encyclopedia_, the formulation of infinite judgement changed to “Spirit is not something that is bone”. This shift was influenced by Kant. In _Logic_, the discourse advances into syllogism, inferential theory, leading to “Spirit is a bone for such-and-such reasons”. In essence, Hegel binarily connected spirit and bone in his youth and introduced a mediating term in this connection later in his life, establishing inferential links. However, the notion of forcibly connecting opposing concepts remains. Therefore, the statement “Ownership is transfer” represents an infinite judgement while simultaneously signifying syllogism that “I truly own this object if I can transfer it to others”. This contributes to the reasoning that “I and objects can be connected through the intermediary of others”, progressing to the inference that “I and others can be connected through objects”, thereby laying the foundation for society. (shrink)

We agree that motivation to share emotions and other mental states is crucial for communicative development, but human infants are highly selective in sharing mental states, and this is well taken evolutionarily. Young chimpanzees may also have motivation to imitate mothers. Thus, uniquely human cognition and culture may not be reduced to a few basic abilities and/or inclinations.

Autism spectrum disorders (ASD) are heterogeneous neurodevelopmental disorders that are reportedly characterized by aberrant neural networks. Recently developed multiscale entropy analysis (MSE) can characterize the complexity inherent in EEG dynamics over multiple temporal scales in the dynamics of neural networks. We encountered an 18-year-old man with ASD whose refractory catatonic obsessive–compulsive symptoms were improved dramatically after electroconvulsive therapy (ECT). In this clinical case study, we strove to clarify the neurophysiological mechanism of ECT in ASD by assessing EEG complexity using MSE. (...) Along with ECT, the frontocentral region showed decreased EEG complexity at higher temporal scales, whereas the occipital region expressed an increase at lower temporal scales. Furthermore, these changes were associated with clinical improvement associated with the elevation of brain-derived neurotrophic factor, which is a molecular hypothesis of ECT, playing key roles in ASD pathogenesis. Changes in EEG complexity in a region-specific and temporal scale-specific manner we found might reflect atypical EEG dynamics in ASD. Although MSE is not a direct approach to measuring neural connectivity and the results are from only a single case, they might reflect specific aberrant neural network activity and the therapeutic neurophysiological mechanism of ECT in ASD. (shrink)

A 10 kHz pulsed X-ray generator utilising a hot-cathode triode in conjunction with a new type of grid control device for controlling X-ray duration is described. The energy-storage condenser was charged up to 70 kV by a power supply, and the electric charges in the condenser were discharged to the X-ray tube repetitively by the grid control device. The maximum values of the grid voltage, the tube voltage, and the tube current were −1.5 kV, 70 kV, and 0.4 A, respectively. (...) The duration of the flash X-ray pulse was primarily determined by the time constant of the grid control device and the cut-off voltage of thermoelectrons. The X-ray duration was controlled within a region of less than 1 ms; the X-ray intensity with a pulse width of 0.27 ms, a charged voltage of 70 kV, and a peak tube current of 0.4 A was 0.92 μC kg −1 at 0.5 m per pulse. The maximum repetition rate was about 10 kHz, and the size of the focal spot was about 3.5×3.5 mm. (shrink)

Transcranial direct current stimulation (tDCS) has been recognized as a promising tool for investigating the causal relationship between specific brain areas of interest and behavior. However, the reproducibility of previous tDCS studies is often questioned because of failures in replication. This study focused on the effects of tDCS on one cognitive domain: beauty perception. To date, the modulation of beauty perception by tDCS has been shown in two studies:Cattaneo et al. (2014)andNakamura and Kawabata (2015). Here, we aimed at replicating their (...) studies and investigating the effects of tDCS on beauty perception using the following parameters: (1) cathodal stimulation over the medial prefrontal cortex (mPFC) (Nakamura and Kawabata, 2015); (2) anodal stimulation over the left dorsolateral prefrontal cortex (lDLPFC) (Cattaneo et al., 2014). We also performed a more focal stimulation targeting the orbitofrontal cortex (OFC) to determine the optimal stimulation site for modulating beauty perception (3). Participants rated the subjectively-perceived beauty of the images before and after the tDCS administration. We divided images into four clusters according to the obtained scores in our preliminary study and examined changes in beauty ratings in each image cluster separately to exclude factors, such as stimuli attributions that may reduce tDCS effects. The results showed no strong effects of tDCS with the same parameters as in previous studies on beauty rating scores in any image cluster. Likewise, anodal stimulation over the OFC did not result in a change in rating scores. In contrast to previous studies, the current study did not corroborate the effects of tDCS on beauty perception. Our findings provide evidence regarding the recent reproducibility issue of tDCS effects and suggest the possible inflation of its effects on cognitive domains. (shrink)

The Vārṣṇeyādhyātma, which is comprised of chapters 203–210 of the 12th Book of the Mahābhārata, is an early exposition of the practice of Yoga centered on the manas and the bodily channel called manovahā. The importance of the Vārṣṇeyādhyātma’s doctrine for the history of Yoga has not been appropriately acknowledged in previous research and its systematic description of the practice of Yoga has never been studied in its entirety. A careful reading of the text suggests that the Vārṣṇeyādhyātma touches upon (...) the physiological as well as psychological aspects of a human being in the context of the practice of Yoga. This paper attempts to reconstruct the Vārṣṇeyādhyātma’s understanding of the manas and the manovahā channel on the basis of a critical reading of Mahābhārata 12.207.16–29. (shrink)

Semiclassical theory based upon complexified classical mechanics is developed for periodically time-dependent scattering systems, which are minimal models of multi-dimensional systems. Semiclassical expression of the wave-matrix is derived, which is represented as the sum of the contributions from classical trajectories, where all the dynamical variables as well as the time are extended to the complex-domain. The semiclassical expression is examined by a periodically perturbed 1D barrier system and an excellent agreement with the fully quantum result is confirmed. In a stronger (...) perturbation regime, the tunneling component of the wave-matrix exhibits a remarkable interference fringes, which is clarified by the semiclassical theory as an interference among multiple complex tunneling trajectories. It turns out that such a peculiar behavior is the manifestation of an intrinsic multi-dimensional effect closely related to a singular movement of singularities possessed by the complex classical trajectories. (shrink)