Biology subjects

Asai, T.

Publications and source records attributed to Asai, T..

17 recordsLinked to original sources

bioRxiv2026

Validity of Low-Dimensional Representation of Whole-Body Movements

Research on impression evaluation from whole-body movements has traditionally focused on the relationships between emotional perception or aesthetic evaluation and movement patterns characterized by local kinematic features and inter-limb coordination. However, because observers perceive the entire body simultaneously when evaluating emotions or aesthetics in real-world viewing situations, impressions derived from whole-body movements should also be investigated. This requires a low-dimensional representation that summarizes whole-body information in an interpretable manner. In the present study, we evaluated whether the state space generated by multidimensional scaling (MDS) provides a valid representation for summarizing whole-body movement. Specifically, using exercises from Radio Calisthenics No. 1, we examined whether distances between points in the MDS state space primarily reflected exercise category rather than individual differences. The results showed that distances in the state space reflected exercise category more strongly than performer identity, suggesting that MDS captures similarities among postures of the same exercise. However, the patterns of distances between conditions varied across exercise categories. These findings suggest that MDS-based state-space representations provide a valid and interpretable approach for summarizing whole-body movements. Nevertheless, further validation using a wider variety of whole-body movements and a more diverse participant population is required.

neuroscience↗

bioRxiv2026

Characterizing load-dependent changes in whole-brain activity patterns during an extended N-back task

Working memory (WM) is a core cognitive function that supports goal-directed behavior by temporarily maintaining and manipulating information. One of the most widely used paradigms for investigating WM function is the N-back task, and numerous neuroimaging studies have examined load-dependent neural responses using a variety of analytical approaches. However, most previous studies have focused on low-to-moderate load ranges (primarily 0-3-back), and it remains unclear how whole-brain activity patterns reconfigure across a broader range of WM demands, including conditions approaching capacity limits. In the present study, we investigated behavioral performance and whole-brain activity patterns across an extended N-back task ranging from 0-back to 7-back. Behavioral analyses revealed that discrimination sensitivity (d') decreased nonlinearly with increasing WM load, whereas reaction time (RT) exhibited an inverted-U pattern, peaking at intermediate load conditions. To characterize load-dependent whole-brain activity patterns, we computed relative activation maps by subtracting the participant-wise mean activation map across all conditions from each condition-specific activation map. Spatial similarity analyses with the Yeo 7-network templates revealed that low-load conditions showed relatively high similarity to default mode network (DMN)-related patterns. Similarity to the dorsal attention network (DAN) and frontoparietal network (FPN) was maximal at intermediate load levels, indicating load-dependent changes in network similarity profiles. High-load conditions were characterized by partial re-emergence of DMN-related patterns, accompanied by reduced DAN/FPN similarity. In addition, semantic similarity analysis using Neurosynth-derived semantic maps revealed relatively high similarity to default mode-related and self-referential representations under low-load conditions. Intermediate-load conditions showed strong correspondence with working memory- and executive control-related representations, whereas high-load conditions exhibited increased similarity to salience-, aversive/interoceptive-, and inhibitory-control-related representations. Together, these findings suggest that increasing WM load is associated not merely with stronger activation, but with changes in whole-brain activity patterns accompanied by nonlinear changes in network similarity profiles across levels of cognitive demand. Furthermore, the relative activation map-based whole-brain pattern analysis used in this study may provide a useful approach for evaluating changes in whole-brain state representations associated with cognitive load.

neuroscience↗

bioRxiv2026

Beyond the Forest and the Trees: Overlooking the Overlooked Terrain of Neural State Dynamics

State-transition approaches, including EEG microstate analysis and related fMRI methods such as hidden Markov models (HMMs) and co-activation pattern (CAP) analysis, provide widely used tools for coarse-graining neural dynamics into a small set of quasi-stable states. Its utility has been demonstrated across resting-state and task paradigms, with broad applications ranging from cognitive neuroscience to candidate biomarkers for psychiatric and neurological disorders. A fundamental limitation remains, however: nearly all downstream temporal measures are conditional on the template maps defined at the outset. In the conventional pipeline, templates are derived from polarity-invariant clustering of voltage maps at global field power (GFP) peaks, making the resulting state definitions sensitive to preprocessing, sampling, initialization, clustering algorithms, and the choice of cluster number. Consequently, the method captures coarse regularities in EEG dynamics, while only weakly constraining the larger geometric organization from which those states emerge. This template dependence poses a major challenge for reproducibility and for comparisons across studies and EEG caps. Here, we revisit this problem from a topological-geometric perspective. We treat templates not as cluster centroids extracted from GFP-peak maps, but as landmarks embedded in the global structure of a state space constructed from mutual similarities among scalp voltage maps. In this formulation, microstate templates are rediscovered as discrete representatives of dominant axes that organize continuous neural-state topography. This reformulation preserves polarity as a meaningful geometric relation instead of eliminating it at the outset as analytical redundancy. It also shifts attention from isolated state labels to the terrain of the state space itself: the broader relational structure within which local states become interpretable. Using this approach, we show that landmark-based state definitions outperform conventional templates in capturing state structure and improving analytical performance. These findings suggest that the central problem in EEG microstate analysis is broader than clustering optimization: it concerns how to define valid nodes for coarse-graining continuous dynamics without discarding the topology that organizes them. By shifting the conceptual basis of microstate analysis from templates to landmarks, the present approach provides a more principled and potentially more stable foundation for state definition, including in fMRI. This topolo-geometric reappraisal extends conventional microstate analysis and opens a path toward more unified comparisons across datasets, paradigms, and recording systems.

neuroscience↗

bioRxiv2026

Behavioural and neural signatures across diverse cognitive demands in a multimodal electroencephalography-functional magnetic resonance imaging design

Efficient multimodal designs that capture differences across cognitive domains and variations in cognitive demand remain limited. In this study, we tested a compact framework with 58 healthy participants who completed multimodal electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) sessions. The framework comprised two complementary batteries: the HCP-aligned multitask paradigm (HCP-mini), which integrates eight HCP-aligned cognitive tasks and rest within a single run, and an extended N-back task ranging from 0-back to 7-back. Designed to support broad cross-domain coverage and matched multimodal assessment, the two batteries captured the expected group-level behavioural structure across modalities. Behavioural performance exceeded chance levels or aligned with findings from previous studies in both EEG and fMRI. Descriptive intraclass correlation coefficient (ICC) analyses showed numerically higher within-modality run-to-run values than between-modality values. At the neural level, HCP-mini fMRI activation patterns closely recapitulated the canonical large-scale task organisation of the original HCP dataset, with corresponding task pairs showing the strongest spatial similarity. Together, these findings demonstrate a compact and efficient framework for multimodal characterisation of cognition across domains and graded cognitive demands.

neuroscience↗

bioRxiv2025

Effects of stimulus modality and response type on oddball stimulus discrimination using polarity-considered EEG microstate labeling

ObjectiveBrain-computer interfaces (BCIs) require effective feature extraction and dimensionality reduction from multidimensional brain signals. Electroencephalogram (EEG) microstate analysis offers a fast and noise-resistant approach by classifying the states of brain signals into spatial distribution patterns (templates). Each EEG segment was assigned the template with the highest spatial correlation, reducing the information to a one-dimensional representation. However, prior BCI studies have often ignored the polarity of spatial distributions in these templates. Incorporating polarity during labeling may enhance classification performance. This study investigated the effectiveness of polarity-considered microstate labeling for classifying infrequent stimuli in an auditory-visual oddball task with implications for BCI applications. MethodEEG recordings were analyzed using polarity-considered microstate labeling to classify infrequent stimuli. This study examined the effects of stimulus modality (auditory or visual), modality conditions (unimodal: stimulus and response in the same modality; cross-modal: stimulus and response in different modalities), and response type (key-press task vs. mental counting task) on classification accuracy. Machine learning models were used for classification, including support vector machine, random forest, logistic regression, XGBoost, CatBoost and K-means methods. ResultsPolarity-considered labeling outperformed the non-polarity approach, especially in decision-tree-based models (20.1% improvement in the key-press task and 22.2% improvement in the mental counting task). A significant interaction was observed between stimulus modality and response type, with the highest accuracy achieved when the infrequent stimuli in the key-press task involved cross-modal visual information. ConclusionThe findings suggest that polarity-considered microstate labeling enhances EEG-based classification. This approach has potential applications in BCI, such as in P300 spellers using cross-modal auditory-visual stimuli.

neuroscience↗

bioRxiv2025

Whole-brain EEG dynamics depending on the stimulus modality and task requirements in oddball tasks

Electroencephalography (EEG) microstates constitute temporal map configurations that reflect the whole brain electrical state. The dynamics of EEG microstates may serve as an effective discretization method for capturing spatiotemporally continuous neural dynamics with high temporal resolution. In this study, we employed polarity-sensitive microstate analysis to investigate whole-brain state transitions during audiovisual oddball tasks. Moreover, we examined how sensory modality and its coupling, types of response to target stimuli, and the physical presence or absence of target stimuli affected EEG dynamics. The results demonstrated that the abovementioned factors affected both behavioral indices and the event-related potential (ERP) components, particularly the P300. Importantly, when considering the topographical polarity of map configuration, transitions to microstate E-, which originates within 300 to 600 ms after stimulus onset and coincides with the typical latency of the P300 component potentially reflect attentional and conscious processes that are associated with the P300. These novel insights into the dynamic transitions of whole brain states during cognitive processes complement the results of traditional ERP analyses.

neuroscience↗

bioRxiv2024

Immediate Modulation of the Blood Oxygenation Level-Dependent Signals by Dual-Site Transcranial Alternating Current Stimulation Propagates Across the Whole Brain

Transcranial alternating current stimulation (tACS) is assumed to target specific brain regions and modulate their activity. Recent discussions of tACS propose that, entraining the phase of brain activity to the stimulation current, stimulation effects extend globally across the whole brain based on phase differences. However, immediate online spatiotemporal propagation of resting-state blood oxygenation level-dependent (BOLD) signals within the brain due to multi-region stimulation remains unclear. The objectives of the present study were three-fold: 1) to elucidate the immediate online effect of tACS on BOLD signal, 2) to examine the extent of the influence on the brain when applying tACS, and 3) to explore whether variations in the phase difference between two brain regions result in differential effects on the stimulated areas and the whole brain. Through two experiments involving high-definition tACS with simultaneous measurements using a functional magnetic resonance imaging (fMRI), we revealed that the immediate online stimulation effects not only altered BOLD signals in the stimulated regions but also propagated across the whole brain in specific spatiotemporal patterns (functional networks). Stimulation effects were observed specifically in regions rich in neural fibres, including the grey and white matter, with no effect in regions containing cerebrospinal fluid. The timing of the signal value peaks depended on the stimulated region and functional networks, with a notable trend observed. Thus, tACS with a specific phase difference in two anatomically connected brain regions can immediately modulate online neural dynamics at both local and global scales. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=80 SRC="FIGDIR/small/610912v2_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@124d6e1org.highwire.dtl.DTLVardef@1976b16org.highwire.dtl.DTLVardef@1f78294org.highwire.dtl.DTLVardef@9df1b7_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2024

Topographical polarity reveals continuous EEG microstate transitions and electric field direction in healthy aging

EEG microstate sequences, representing whole-brain spatial potential distribution patterns of the EEG, offer valuable insights for capturing spatiotemporally continuous and fluctuating neural dynamics with high temporal resolution through appropriate discretization. Recent studies suggest that EEG microstate transitions are gradual and continuous phenomena, contrary to the classical view of binary transitions. This study aimed to update conventional microstate analysis to reflect continuous EEG dynamics and examine differences in age-related electrophysiological state transitions. We considered the relative positions of EEG microstates on the neural manifold and their topographical polarity. Transition probability results showed fewer transitions on the microstate D-C-E axis in older adults. In contrast, transitions among microstates A, D, and B increased in the older group and were mainly observed within polarity. Furthermore, the 100 microstate transitions, which are variations of the shortest transitions between 10 microstates, could be reduced to 8 principal components based on the co-occurrence of each transition, including hubs C and E, planar transitions through msA/B and D, and unidirectional transition components. Several transition components were potentially significant predictors of age group. These features were nearly replicated in independent data, indicating their robustness in characterizing age-related electrophysiological spatiotemporal dynamics.

neuroscience↗

bioRxiv2023

Spatio-temporal "global" neurodynamics in both continuous and discrete pictures for human brains

The neural manifold in state space represents the mass neural dynamics of a biological system. A challenging modern approach treats the brain as a whole in terms of the interaction between the agent and the world. Therefore, we need to develop a method for this global neural workspace. The current study aimed to visualize spontaneous neural trajectories regardless of their measuring modalities (electroencephalography [EEG], functional magnetic resonance imaging [fMRI], and magnetoencephalography [MEG]). First, we examined the possible visualization of EEG manifolds. These results suggest that a spherical surface can be clearly observed within the spatial similarity space where canonical microstates are on-manifold. Once valid (e.g., differentiable) and useful (e.g., low-dimensional) manifolds are obtained, the nature of the sphere, such as shape and size, becomes a possible target of interest. Because these should be practically useful, we suggest advantages of the EEG manifold (essentially continuous) or the state transition matrix (coarse-grained discrete). Finally, because our basic procedure is modality-independent, MEG and fMRI manifolds were also compared. These results strongly suggest the need to update our understanding of neural mass representations to include robust "global" dynamics.

neuroscience↗

bioRxiv2022

Unique genomic sequences in novel Mycobacterium avium subsp. hominissuis lineage enabled fine scale tracing the transmission route during pig movement

Mycobacterium avium subsp. hominissuis (MAH) is one of the most prevalent mycobacteria causing non-tuberculous mycobacterial disease in humans and animals. Of note, MAH is a major cause of mycobacterial granulomatous mesenteric lymphadenitis outbreaks in pig populations. To determine the precise source of infection of MAH in a pig farm and to clarify the epidemiological relationship among pig, human and environmental MAH lineages, we collected 50 MAH isolates from pigs reared in Japan and determined draft genome sequences of 30 isolates. A variable number of tandem repeat analysis revealed that most pig MAH isolates in Japan were closely related to North American, European and Russian human isolates but not to those from East Asian human and their residential environments. Historical recombination analysis revealed that most pig isolates could be classified into SC2/4 and SC3, which contain MAH isolated from pig, European human and environmental isolates. Half of the isolates in SC2/4 had many recombination events with MAH lineages isolated from humans in East Asia. To our surprise, four isolates belonged to a new lineage (SC5) in the global MAH population. Members of SC5 had few footprints of inter-lineage recombination in the genome, and carried 80 unique genes, most of which were located on lineage specific-genomic islands. Using unique genetic features, we were able to trace the putative transmission route via their host pigs. Together, we clarify the possibility of species-specificity of MAH in addition to local adaptation. Our results highlight two transmission routes of MAH, one exposure on pig farms from the environment and the other via pig movement. Moreover, our study also warns that the evolution of MAH in pigs is influenced by MAH from patients and their residential environments, even if the MAH are genetically distinct. HighlightsO_LIVariable number of tandem repeat analysis of Mycobacterium avium subsp. hominissuis (MAH) isolated from pigs (n=50) were conducted. C_LIO_LIDraft genome sequences of MAH (n=30) and genome analysis were conducted. C_LIO_LIPig MAHs were genetically far from East Asian human isolates and close to those of Western countries. C_LIO_LINovel MAH lineage which were transmitted farms by pig movement was found. C_LIO_LIHuman MAH isolates influenced the evolution of pig isolates. C_LI

microbiology↗

bioRxiv2021

"XR Mark Test" Reveals Sensorimotor Body Representation in Toddlers

Research on multisensory integration--particularly visuo-proprioceptive integration--has renewed interest in how body representation develops in early childhood. In the past decade, researchers have attempted to adapt body-illusion tasks such as the rubber hand illusion for young children, yet difficulties with verbal reports and inconsistent behavioral responses limit their usefulness for toddlers. At the same time, children naturally begin to recognize their mirror image as self during the early toddler period, suggesting that mirror-based localization may offer a developmentally appropriate window onto emerging body representation. However, the classic mark test is not suitable for repeated measurements. We developed Bodytoypo, a cross-reality body-part localization task that projects a life-size self-image onto a screen and overlays AR markers on multiple body locations using real-time skeleton detection. Toddlers touched the corresponding location on their actual body, allowing quantitative evaluation of localization accuracy. Thirty 2- and 3-year-olds participated. We recorded first-touch outcomes, touch error, reaction times, and hand trajectories. Conventional coding was combined with an automated statistical analysis to estimate factors predicting touch error. Results showed that Bodytoypo is feasible for repeated use with toddlers and provides reliable indices of body-part localization. Automated statistical analyses identified several reaching strategies that appeared to reflect differences in localization precision. These findings suggest age-related changes in how visual information and motor prediction are weighted during visuo-proprioceptive integration. Bodytoypo offers a promising behavioral index for clarifying how sensorimotor information (body schema) and spatial understanding of body parts (body topology) jointly contribute to the early development of body representation.

animal behavior and cognition↗

bioRxiv2021

Genomic features of Mycobacterium avium subsp. hominissuis isolated from pigs in Japan.

Mycobacterium avium subsp. hominissuis (MAH) is one of the most important agents causing non-tuberculosis mycobacterial infection in humans and pigs. Genome analysis on MAH of human isolates has been proceeding, however, those of pigs are limited despite its potential source of infection to human. In the current study, we obtained 30 draft genome sequences of MAH of pigs reared in Japan. The 30 draft genomes consisted of 4,848,678 - 5,620,788 bp length, 4,652 - 5,388 coding genes and 46 - 75 (Med: 47) tRNAs. All isolates had restriction modification associated genes and 185 - 222 predicted virulence genes. Two isolates had tRNA arrays and one isolate had a clustered regularly interspaced short palindromic repeat (CRISPR) region. Our results will be useful for evaluation of the ecology of MAH by providing a foundation for genome-based epidemiological studies.

microbiology↗

bioRxiv2021

Overexpression of the RNA-binding protein NrdA affects global gene expression and secondary metabolism in Aspergillus species

RNA-binding protein Nrd1 plays a role in RNA polymerase II transcription termination. In this study, we showed that the orthologous NrdA is important in global mRNA expression and secondary metabolism in Aspergillus species. We constructed an nrdA conditional expression strain using the Tet-On system in Aspergillus luchuenesis mut. kawachii. Downregulation of nrdA caused a severe growth defect, indicating that NrdA is essential for the proliferation of A. kawachii. Parallel RNA-sequencing and RNA immunoprecipitation-sequencing analysis identified potential NrdA-interacting transcripts, corresponding to 32% of the predicted protein coding genes of A. kawachii. Subsequent gene ontology analysis suggested that overexpression of NrdA affects the production of secondary metabolites. To clarify this, we constructed NrdA-overexpressing strains of Aspergillus nidulans, Aspergillus fumigatus, and Aspergillus oryzae. Overexpression of NrdA reduced the production of sterigmatocystin and penicillin in A. nidulans, as well as that of helvolic acid and pyripyropene A in A. fumigatus. Moreover, it increased the production of kojic acid and reduced production of penicillin in A. oryzae. These effects were accompanied by almost consistent transcriptional changes in the relevant genes. Collectively, these results suggest that NrdA is the essential RNA-binding protein, which plays a significant role in global gene expression and secondary metabolism in Aspergillus species. IMPORTANCENrd1, a component of the Nrd1-Nab3-Sen1 complex, is an essential RNA-binding protein involved in transcriptional termination in yeast. However, its role in filamentous fungi has not been studied. In this study, we characterized an orthologous NrdA in the Aspergillus species, identified potential NrdA-interacting mRNA, and investigated the effect of overexpression of NrdA on mRNA expression in Aspergillus luchuensis mut. kawachii. The results indicated that NrdA controls global gene expression involved in versatile metabolic pathways, including the secondary metabolic process. We demonstrated that NrdA overexpression significantly affected the production of secondary metabolites in Aspergillus nidulans, Aspergillus oryzae, and Aspergillus fumigatus. Our findings are of importance to the fungal research community because the secondary metabolism is an industrially and clinically important aspect for the Aspergillus species.

microbiology↗

bioRxiv2020

My voice therefore I spoke: sense of agency over speech enhanced in hearing self-voice

The subjective experience of causing an action is known as the sense of agency. Dysfunction in the sense of agency has been suggested as a cause of auditory hallucinations (AHs), an important diagnostic criterion for schizophrenia. However, agency over speech has not been extensively characterized in previous empirical studies. Here, we examine both implicit and explicit measures of the sense of agency and reveal bottom-up and top-down components that constitute self-agency during speech. The first is action-outcome causality, which is perceived based on a low-level sensorimotor process when hearing their own voice following their speech. The second component is self-voice identity, which is embedded in the acoustic quality of voice and dominantly influences agency over speech at the cognitive judgment level. Our findings provide profound insight into the sense of agency over speech and present an informative perspective for understanding aberrant experience in AHs.

neuroscience↗

bioRxiv2020

Promoter activity-based case-control association study on SLC6A4 highlighting hypermethylation and altered amygdala volume in male patients with schizophrenia

Associations between altered DNA methylation of the serotonin transporter (5-HTT)-encoding gene SLC6A4 and early life adversity, mood and anxiety disorders, and amygdala reactivity have been reported. However, few studies have examined epigenetic alterations of SLC6A4 in schizophrenia (SZ). We examined CpG sites of SLC6A4, whose DNA methylation levels have been reported to be altered in bipolar disorder, using three independent cohorts of patients with SZ and age-matched controls. We found significant hypermethylation of a CpG site in SLC6A4 in male patients with SZ in all three cohorts. We showed that chronic administration of risperidone did not affect the DNA methylation status at this CpG site using common marmosets, and that in vitro DNA methylation at this CpG site diminished the promoter activity of SLC6A4. We then genotyped the 5-HTT-linked polymorphic region (5-HTTLPR) and investigated the relationship among 5-HTTLPR, DNA methylation, and amygdala volume using brain imaging data. We found that patients harboring low-activity 5-HTTLPR alleles showed hypermethylation and they showed a negative correlation between DNA methylation levels and left amygdala volumes. These results suggest that hypermethylation of the CpG site in SLC6A4 is involved in the pathophysiology of SZ, especially in male patients harboring low-activity 5-HTTLPR alleles.

genetics↗

bioRxiv2019

The self as a generative, teleological, and subjective prior: Mutually-modulated temporal agency

How can we certify our existence? Recent theoretical studies have suggested that, in the brain, the effect inversely infers the possibility of the existence of the self as the cause. While this Bayesian view of the sense of agency is widely accepted, empirical evidence in support of this theory is still lacking. The current study examined outcome-modulated agency in terms of time perception in seven experiments, with a total of 90 participants. It was hypothesized that perceptual generation, not termination, should subjectively infer the existence of the self, even though both include the same stimuli and are driven by the same teleological action. Results suggest support for the hypothesis (Experiments 1 and 2). Participants judged stronger self-agency, detected less delay, or felt shorter duration for auditory generation, compared with termination, which was driven by the same volitional key-press. Furthermore, the main experiment, Experiment 3, focused on temporal probability distributions both for action and outcome (e.g., standard deviations or relative entropy), and concluded that the observed contrast in onset/offset agency indicates a mutual or bidirectional relationship between cause and effect only during agentive action, characterized by active (i.e., teleological) generation. Finally, the concurrent theoretical models for volitional action-modulated time perception are discussed on the basis of the suggested triplet (generativity, teleology, and subjectivity) dimensions of agency.\n\nExtended abstractThe sense of agency refers to the subjective experience of generating ones own actions (Gallagher, 2000). Within the past decade, research on this subject has increased, as increased understanding of human agency could be a window into knowing how we are aware of ourselves, and possibly allowing for a better understanding of mental illnesses, like schizophrenia. However, \"free will,\" \"self-consciousness,\" and/or \"volition\" are concepts that are always difficult to empirically investigate (Frith & Haggard, 2018). Researchers do not know exactly what occurs in our sensorium during \"agentive action.\" However, three conceptions could represent genuine dimensions of agency: generativity, teleology, and subjectivity (Haggard, 2019).\n\nRecent theoretical studies have suggested that, in the brain, the effect inversely infers the possibility of the existence of the self as the cause. This Bayesian view of the sense of agency may provide an explanation for classical statements, such as \"ego cogito, ergo sum (I think, therefore I am),\" \"cogito cogito, ergo cogito sum (I think that I think, therefore I think that I am),\" \"I move, therefore I am,\" or \"I predict, therefore I am.\" (e.g., Corlett, 2017). All of these theoretical claims implicitly refer to the Bayesian \"inverse\" probability or inference (e.g., \"thought as action\"), where the effect (perception) retrospectively postdicts the cause (action), as well as the action predicting the following perception (Figure 1, including generativity, teleology, and subjectivity as triplet dimensions of agency). This bidirectional temporal relationship between action and perception can be empirically examined in terms of the \"certification of the self\" or self as prior.\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=126 SRC=\"FIGDIR/small/519934_fig1.gif\" ALT=\"Figure 1\">\nView larger version (23K):\norg.highwire.dtl.DTLVardef@e2d70dorg.highwire.dtl.DTLVardef@94b9d0org.highwire.dtl.DTLVardef@330b16org.highwire.dtl.DTLVardef@11d00a4_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOFigure 1.C_FLOATNO The theoretical hypothesis of cross-dependency between action and sensation in time.\n\nNote: Bayesian subjective probability ignores the order between cause and effect (i.e., the physical temporal arrow), even if we make a distinction between the two (prediction vs. postdiction). Furthermore, the posterior distributions (as a result of dissolving the pre/postdiction error) for action-timing and sensation-timing are mutually-tugged since both share the same prior (i.e., the self must be the immediate active generator, as the current study suggests). Icon made by Freepik from www.flaticon.com.\n\nC_FIG\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=148 SRC=\"FIGDIR/small/519934_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (32K):\norg.highwire.dtl.DTLVardef@1151ce4org.highwire.dtl.DTLVardef@11bc371org.highwire.dtl.DTLVardef@1bc6393org.highwire.dtl.DTLVardef@12d48c8_HPS_FORMAT_FIGEXP M_FIG C_FIG\n\nThe current study examined effect-modulated agency in terms of time perception in seven experiments, conducted with a total of 90 participants. We hypothesized that perceptual generation, not termination, should inversely infer the self in action, even though both include the same stimuli, and are driven by the same action. Results support this hypothesis (Experiments 1 and 2). Participants judged stronger self-agency, detected less delay, or felt shorter duration for auditory generation, compared to termination, in instances driven by a key-press of his/her own volition, but may have also had different \"priors\" (i.e., self or other, as a categorical causal structure selection or model weighting). Furthermore, the main experiment, Experiment 3, focused on probability distributions both for action and outcome on the same temporal axis (e.g., standard deviations or relative entropy), and concluded that this contrast in onset/offset agency indicates the mutual or bidirectional relationship between cause and effect only during agentive action, characterized by the active generation (Figure 2). In summary, results indicate that the self is learned as a prior to being an independent agent that can immediately cause actions to occur within the environment merely through ones own volition. This interpretation is highly congruent with the literal meaning of the sense of agency and also with the theory of the triplet dimensions of agency.\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=129 SRC=\"FIGDIR/small/519934_fig2.gif\" ALT=\"Figure 2\">\nView larger version (30K):\norg.highwire.dtl.DTLVardef@57f98org.highwire.dtl.DTLVardef@fbf3f7org.highwire.dtl.DTLVardef@14e0bcborg.highwire.dtl.DTLVardef@e86727_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOFigure 2.C_FLOATNO Summarized results across Experiments 1(A,B,C) and 2(A,B,C).\n\nNote: Asterisks represent the significant differences only between onset and offset conditions. Dashed arches represent the main effect of on/offset condition. Error bars represents {+/-} 1 SE. ** p < .01, * p < .05, {dagger} p < .10, see Table S2 for full ANOVA results.\n\nC_FIG\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=141 SRC=\"FIGDIR/small/519934_ufig2.gif\" ALT=\"Figure 2\">\nView larger version (32K):\norg.highwire.dtl.DTLVardef@1cc466corg.highwire.dtl.DTLVardef@2375feorg.highwire.dtl.DTLVardef@17a4edorg.highwire.dtl.DTLVardef@4ceba8_HPS_FORMAT_FIGEXP M_FIG C_FIG\n\nO_TBL View this table:\norg.highwire.dtl.DTLVardef@39d38org.highwire.dtl.DTLVardef@146d3d9org.highwire.dtl.DTLVardef@fe5678org.highwire.dtl.DTLVardef@1df0ffaorg.highwire.dtl.DTLVardef@19205d1_HPS_FORMAT_FIGEXP M_TBL O_FLOATNOTable S2.C_FLOATNO O_TABLECAPTIONThe means and SDs of reports in each condition in Experiment 3.\n\nC_TABLECAPTION C_TBL We believe that the current study successfully observed the previously invisible relationship between action and perception in favor of advanced analysis, based on information theory, computational neuroscience (Figure 3), and theoretical discussions.\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC=\"FIGDIR/small/519934_fig3.gif\" ALT=\"Figure 3\">\nView larger version (20K):\norg.highwire.dtl.DTLVardef@1bc1dc5org.highwire.dtl.DTLVardef@146975borg.highwire.dtl.DTLVardef@17aed8forg.highwire.dtl.DTLVardef@1825b88_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOFigure 3.C_FLOATNO The motor, tone, and intentional binding effect in Experiment 3.\n\nNote: Dashed arches represent the main effects of factors. Error bars represents {+/-} 1 SE. ** p < .01, * p < .05, {dagger} p < .10, see Table S2 for full ANOVA results.\n\nC_FIG\n\nThis manuscript has not been published or presented elsewhere in part or in entirety. There are no conflicts of interest to declare.\n\n\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=147 SRC=\"FIGDIR/small/519934_ufig3.gif\" ALT=\"Figure 3\">\nView larger version (34K):\norg.highwire.dtl.DTLVardef@1477b04org.highwire.dtl.DTLVardef@1dd4b72org.highwire.dtl.DTLVardef@18438aforg.highwire.dtl.DTLVardef@1a57f7a_HPS_FORMAT_FIGEXP M_FIG C_FIG ReferencesO_BIBINTEXTCorlettP. PredictI, Therefore I Am: Perturbed Predictive Coding Under Ketamine and in Schizophrenia. O_TITLEBiological PsychiatryC_TITLE, O_VOLUMENR81C_VOLUMENR, O_FIRSTPAGE465C_FIRSTPAGE-466 (O_DATE2017C_DATE).C_BIBINTEXT\n\nO_BIBINTEXTFrithC. D., HaggardP. Volition and the Brain - Revisiting a Classic Experimental Study. O_TITLETrends NeurosciC_TITLE. O_VOLUMENR41C_VOLUMENR, O_FIRSTPAGE405C_FIRSTPAGE-407 (O_DATE2018C_DATE).C_BIBINTEXT\n\nO_BIBINTEXTGallagherS. Philosophical conceptions of the self: implications for cognitive science. O_TITLETrends Cogn. Sci.C_TITLE O_VOLUMENR4C_VOLUMENR, O_FIRSTPAGE14C_FIRSTPAGE-21 (O_DATE2000C_DATE).C_BIBINTEXT\n\nO_BIBINTEXTHaggardP. The Neurocognitive Bases of Human Volition. O_TITLEAnnu Rev Psychol. (in press)C_TITLEC_BIBINTEXT

neuroscience↗

bioRxiv2018

Self-agency built with sensorimotor processing: Decoding self-other action attribution in the human brain

A sense of agency can be defined as a subjective experience that I am the one who is causing or generating an action. Several brain regions have been proposed as neural substrates of the subjective experience; however, how the information is processed and organized by each region to achieve the sense of agency still remains unclear. In this study, we have clarified the neural representations corresponding to three processes namely, sensorimotor error, feeling of agency, and judgment of agency. Specifically, we found that the widespread sensorimotor areas represent sensorimotor error information. The right inferior parietal lobe represents the information solely on self-/other-attribution even during movements, which corresponds to the feeling of agency. Finally, the right inferior frontal gyrus shows a distinct representation between self- and other-attribution immediately before reporting the judgment on the movement attribution. These results suggest that the brain builds a sense of agency by developing distinct types of information each corresponding to the three processes with the passage of time.

neuroscience↗