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Developing a short-term phenomenological training program: A report of methodological lessons
Get PDFWe discuss our attempts to develop a short-term phenomenological training program for training naïve participants in phenomenological skills. After reviewing existing methodologies for collecting phenomenological data and clarifying the benefit of the short-term training approach, we present two training programs and two experiments that tested their effectiveness. Experiment 1 tested the two-stage training program, which consists of (i) the illusion training which instructs participants to describe the experience of a visual illusion and (ii) the guidance training which offers individualized feedbacks for improving their description. This program proved effective, but also excessively skill-demanding. Experiment 2 tested the one-stage training program, consisting only of the illusion training; it was easier to use, but exhibited a smaller training effect. The paper concludes by delineating methodological lessons from the experiments focusing on three themes: (i) Individual difference in phenomenological aptitude; (ii) Bounded transferability of phenomenological skills; (iii) Active intervention in the learning process.journal articl
Respiration-Locking of Olfactory Receptor and Projection Neurons in the Mouse Olfactory Bulb and Its Modulation by Brain State
Get PDFFor sensory systems of the brain, the dynamics of an animal’s own sampling behavior has a direct consequence on ensuing computations. This is particularly the case for mammalian olfaction, where a rhythmic flow of air over the nasal epithelium entrains activity in olfactory system neurons in a phenomenon known as sniff-locking. Parameters of sniffing can, however, change drastically with brain states. Coupled to the fact that different observation methods have different kinetics, consensus on the sniff-locking properties of neurons is lacking. To address this, we investigated the sniff-related activity of olfactory sensory neurons (OSNs), as well as the principal neurons of the olfactory bulb (OB), using 2-photon calcium imaging and intracellular whole-cell patch-clamp recordings in vivo, both in anesthetized and awake mice. Our results indicate that OSNs and OB output neurons lock robustly to the sniff rhythm, but with a slight temporal shift between behavioral states. We also observed a slight delay between methods. Further, the divergent sniff-locking by tufted cells (TCs) and mitral cells (MCs) in the absence of odor can be used to determine the cell type reliably using a simple linear classifier. Using this classification on datasets where morphological identification is unavailable, we find that MCs use a wider range of temporal shifts to encode odors than previously thought, while TCs have a constrained timing of activation due to an early-onset hyperpolarization. We conclude that the sniff rhythm serves as a fundamental rhythm but its impact on odor encoding depends on cell type, and this difference is accentuated in awake mice.journal articl
Distinct Mechanisms of Over-Representation of Landmarks and Rewards in the Hippocampus
Get PDFIn the hippocampus, locations associated with salient features are represented by a disproportionately large number of neurons, but the cellular and molecular mechanisms underlying this over-representation remain elusive. Using longitudinal calcium imaging in mice learning to navigate in virtual reality, we find that the over-representation of reward and landmark locations are mediated by persistent and separable subsets of neurons, with distinct time courses of emergence and differing underlying molecular mechanisms. Strikingly, we find that in mice lacking Shank2, an autism spectrum disorder (ASD)-linked gene encoding an excitatory postsynaptic scaffold protein, the learning-induced over-representation of landmarks was absent whereas the over-representation of rewards was substantially increased, as was goal-directed behavior. These findings demonstrate that multiple hippocampal coding processes for unique types of salient features are distinguished by a Shank2-dependent mechanism and suggest that abnormally distorted hippocampal salience mapping may underlie cognitive and behavioral abnormalities in a subset of ASDs.journal articl
Features of the Coupled Nuclear–Electron Spin Precession in the Bose–Einstein Condensate of Magnons
Get PDFThe experimental detection of the Bose-Einstein condensate of magnons in coupled nuclear-electron spin precession in antiferromagnets brings the prospect of its use for magnonics and computer calculations. In particular, an attractive feature of such systems is a relatively large spin coherence time compared to traditional iron yttrium garnet samples. However, the observed Bose-Einstein condensation of magnons contradicts the Suhl-Nakamura model and the Bloch equations, which are usually used for these systems. The results of a direct experiment in antiferromagnetic MnCO3 performed in this work indicate that the Suhl-Nakamura model and the Bloch equations cannot adequately describe the coupled nuclear-electron spin motion at large levels of magnon excitation.journal articl
Probing SWATH‐MS as a tool for proteome level quantification in a nonmodel fish
Get PDFQuantitative proteomics via mass spectrometry can provide valuable insight into molecular and phenotypic characteristics of a living system. Recent mass spectrometry developments include data-independent acquisition (SWATH/DIA-MS), an accurate, sensitive and reproducible method for analysing the whole proteome. The main requirement for this method is the creation of a comprehensive spectral library. New technologies have emerged producing larger and more accurate species-specific libraries leading to a progressive collection of proteome references for multiple molecular model species. Here, for the first time, we set out to compare different spectral library constructions using multiple tissues from a coral reef fish to demonstrate its value and feasibility for nonmodel organisms. We created a large spectral library composed of 12,553 protein groups from liver and brain tissues. Via identification of differentially expressed proteins under fish exposure to elevated pCO2 and temperature, we validated the application and usefulness of these different spectral libraries. Successful identification of significant differentially expressed proteins from different environmental exposures occurred using the library with a combination of data-independent and data-dependent acquisition methods as well as both tissue types. Further analysis revealed expected patterns of significantly up-regulated heat shock proteins in a dual condition of ocean warming and acidification indicating the biological accuracy and relevance of the method. This study provides the first reference spectral library for a nonmodel organism. It represents a useful guide for future building of accurate spectral library references in nonmodel organisms allowing the discovery of ecologically relevant changes in the proteome.journal articl
How to Improve Behavioral Parent and Teacher Training for Children with ADHD: Integrating Empirical Research on Learning and Motivation into Treatment
Get PDFAttention deficit hyperactivity disorder [ADHD] is one of the most common psychiatric disorders of childhood with poor prognosis if not treated effectively. Recommended psychosocial evidence-based treatment for preschool and school-aged children is behavioral parent and teacher training [BPT]. The core elements of BPT are instrumental learning principles, i.e., reinforcement of adaptive and the ignoring or punishment of non-adaptive behaviors together with stimulus control techniques. BPT is moderately effective in reducing oppositional behavior and improving parenting practices; however, it does not reduce blinded ratings of ADHD symptoms. Also after training effects dissipate. This practitioner review proposes steps that can be taken to improve BPT outcomes for ADHD, based on purported causal processes underlying ADHD. The focus is on altered motivational processes (reward and punishment sensitivity), as they closely link to the instrumental processes used in BPT. Following a critical analysis of current behavioral treatments for ADHD, we selectively review motivational reinforcement-based theories of ADHD, including the empirical evidence for the behavioral predictions arising from these theories. This includes consideration of children's emotional reactions to expected and unexpected outcomes. Next we translate this evidence into potential ADHD-specific adjustments designed to enhance the immediate and long-term effectiveness of BPT programs in addressing the needs of children with ADHD. This includes the use of remediation strategies for proposed deficits in learning not commonly used in BPT programs and cautions regarding the use of punishment. Finally, we address how these recommendations can be effectively transferred to clinical practice.journal articl
Complex Relationship between Tunneling Patterns and Individual Behaviors in Termites
Get PDFThe nests built by social insects are complex group-level structures that emerge from interactions among individuals following simple behavioral rules. Nest patterns vary among species, and the theory of complex systems predicts that there is no simple one-to-one relationship between variation in collective patterns and variation in individual behaviors. Therefore, a species-by-species comparison of the actual building process is essential to understand the mechanism producing diverse nest patterns. Here, we compare tunnel formation of three termite species and reveal two mechanisms producing interspecific variation: in one, a common behavioral rule yields distinct patterns via parameter tuning, and in the other, distinct rules produce similar patterns. We found that two related species transport sand in the same way using mandibles but build tunnels with different degrees of branching. The variation arises from different probabilities of choosing between two behavioral options at crowded tunnel faces: excavating the sidewall to make a new branch or waiting for clearance to extend the current tunnel. We further discovered that a third species independently evolved low-branched patterns using different building rules, namely, a bucket brigade that can excavate a crowded tunnel. Our findings emphasize the importance of direct comparative study of collective behaviors at both individual and group levels.journal articl
Micro- and Nanoplastic in Okinawa: Potential impacts on planktonic microalgae and Endosymbiotic Dinoflagellates
Get PDFOkinawa Institute of Science and Technology Graduate UniversityDoctor of PhilosophyFrom coast to gyre, from surface to deep sea, the study of marine plastic pollution takes us on a journey of potential harm through our marine ecosystems, where man-made plastics break down into ever smaller pieces along their way. Studying micro- and nanoplastic pollution in field and laboratory work, new insights into microalgae interactions, and these smallest plastic particles were gathered. Mimicking two different environments in the laboratory - reef and open ocean water - an effect assessment of four different microalgae species (Diatoms Skeletonema grethae and Odontella aurita, cyanobaterium Synechococcus elongatus, endosymbiontic dinoflagellates Symbiodinium tridacnidorum and Cladocopium sp.) and their interaction with micro- and nanoplastics at different sizes, types, and concentrations was conducted. Aggregation, sedimentation, photosynthesis, extracellular substance production, and RNA expression patterns were all found to be affected. Specifically, hetero-aggregation with nanoplastic led to neutrally buoyant marine snow, differentially expressed genes, and reduced photosynthesis. Furthermore, an exposure assessment around Okinawa, an isolated subtropical island with fringing reefs, found that microplastic pollution follows the island’s population gradient. Polyethylene was the most abundant polymer found 45%, and of the ubiquitous sub 20 μm plastics, the majority was embedded in organic matter
Essential functions of the CNOT7/8 catalytic subunits of the CCR4-NOT complex in mRNA regulation and cell viability
Get PDFShortening of mRNA poly(A) tails (deadenylation) to trigger their decay is mediated mainly by the CCR4-NOT deadenylase complex. While four catalytic subunits (CNOT6, 6L 7, and 8) have been identified in the mammalian CCR4-NOT complex, their individual biological roles are not fully understood. In this study, we addressed the contribution of CNOT7/8 to viability of primary mouse embryonic fibroblasts (MEFs). We found that MEFs lacking CNOT7/8 expression [Cnot7/8-double knockout (dKO) MEFs] undergo cell death, whereas MEFs lacking CNOT6/6L expression (Cnot6/6l-dKO MEFs) remain viable. Co-immunoprecipitation analyses showed that CNOT6/6L are also absent from the CCR4-NOT complex in Cnot7/8-dKO MEFs. In contrast, either CNOT7 or CNOT8 still interacts with other subunits in the CCR4-NOT complex in Cnot6/6l-dKO MEFs. Exogenous expression of a CNOT7 mutant lacking catalytic activity in Cnot7/8-dKO MEFs cannot recover cell viability, even though CNOT6/6L exists to some extent in the CCR4-NOT complex, confirming that CNOT7/8 is essential for viability. Bulk poly(A) tail analysis revealed that mRNAs with longer poly(A) tails are more numerous in Cnot7/8-dKO MEFs than in Cnot6/6l-dKO MEFs. Consistent with elongated poly(A) tails, more mRNAs are upregulated and stabilized in Cnot7/8-dKO MEFs than in Cnot6/6l-dKO MEFs. Importantly, Cnot6/6l-dKO mice are viable and grow normally to adulthood. Taken together, the CNOT7/8 catalytic subunits are essential for deadenylation, which is necessary to maintain cell viability, whereas CNOT6/6L are not.journal articl