American Physiological SocietyActa Medica Okayama0022-307713542026Characteristics of cross-modal negative BOLD responses in the human sensory subcortex and cortex747759ENToshikazuMiyataDivision of Sensory and Cognitive Brain Mapping, Department of System Neuroscience, National Institute for Physiological SciencesMasakiFukunagaSection of Brain Function Information, National Institute for Physiological SciencesJunxiangLuoDivision of Sensory and Cognitive Brain Mapping, Department of System Neuroscience, National Institute for Physiological SciencesIsaoYokoiNational Institute for Physiological SciencesTetsuyaYamamotoSection of Brain Function Information, National Institute for Physiological SciencesAyumiYoshiokaSection of Brain Function Information, National Institute for Physiological SciencesJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTomoyoMoritaCenter for Information and Neural Networks (CiNet), Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT)HiromasaTakemuraDivision of Sensory and Cognitive Brain Mapping, Department of System Neuroscience, National Institute for Physiological SciencesFunctional magnetic resonance imaging (fMRI) is a noninvasive method for measuring human brain activity based on blood oxygenation level-dependent (BOLD) responses. Although many studies have reported positive BOLD responses evoked by sensory stimuli, others have reported negative BOLD responses (NBRs) in the sensory cortex when stimuli from different sensory modalities are presented (i.e., cross-modal NBRs). We conducted an fMRI experiment to better understand the characteristics of cross-modal NBRs in subcortical and cortical regions. Auditory and visual stimuli were presented unilaterally to one ear and to either the left or right visual field, respectively. The lateral geniculate nucleus and medial geniculate nucleus did not show a significant cross-modal NBR. In contrast, the primary auditory cortex showed a significant cross-modal NBR when visual stimuli were presented in either the contralateral or ipsilateral visual fields. Finally, we found that the cross-modal NBR in the early visual cortex was highly variable across subjects and did not exhibit consistent trends. However, each subject’s data exhibited considerable split-half reliability. Our results suggest that cross-modal NBR in the auditory cortex likely reflects mechanisms such as interhemispheric suppression, rather than those coordinated within the same hemisphere.<br>
NEW & NOTEWORTHY This study demonstrated that the human primary auditory cortex showed a significant cross-modal negative BOLD response bilaterally, regardless of the visual field in which the visual stimuli were presented. This result suggests that the cross-modal negative BOLD response is not an epiphenomenon of visual cortex activation predominantly observed in the contralateral hemisphere, but is more likely to reflect interhemispheric suppression mechanisms.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0010-94521942026Increasing visual uncertainty modulates multisensory decision-making5062ENXiangfuYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityWeipingYangDepartment of Psychology, Faculty of Education, Hubei UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityThe brain integrates and transforms information from multiple senses to make optimal decisions, a process that is critical for navigating complex environments with perceptual uncertainty. Despite a growing consensus that individuals adapt flexibly to uncertain sensory input, whether increasing visual uncertainty influences the decision process itself or other, non-decision sensory processes during multisensory decision-making are unclear. Here, an audiovisual categorization task was used to examine the responses of human participants (N = 30) to visual and audiovisual stimuli under low-, medium-, and high-uncertainty conditions. Modeling the behavioral data using a drift‒diffusion model indicated that increased visual uncertainty in the audiovisual context decreased the evidence accumulation rate but had no effect on non-decision processes. Electrophysiological recordings confirmed and expanded upon these results: increased visual uncertainty in the audiovisual context reduced the amplitude during the late decision-making stage (300–380 msec) but had no effect on the amplitude during the early sensory encoding stage (140–220 msec). More importantly, electroencephalography analyses revealed that audiovisual integration in the early sensory encoding stage occurred robustly across all visual uncertainty conditions, whereas audiovisual integration in the late stage occurred only under medium and high visual uncertainty conditions. This study demonstrated that increased visual uncertainty modulates the decision process itself rather than early sensory encoding during multisensory decision-making. Moreover, multisensory integration strategies dynamically adapt to increasing visual uncertainty by engaging different mechanisms to maintain effective decision-making.No potential conflict of interest relevant to this article was reported.MDPI AGActa Medica Okayama2076-342515112025Sensory Modality-Dependent Interplay Between Updating and Inhibition Under Increased Working Memory Load: An ERP Study1178ENYuxiLuoGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityAoGuoDepartment of Psychology, Institute of Education, China West Normal UniversityJinglongWuFaculty of Biomedical Engineering, Shenzhen University of Advanced TechnologyJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityBackground/Objectives: Working memory (WM) performance relies on the coordination of updating and inhibition functions within the central executive system. However, their interaction under varying cognitive loads, particularly across sensory modalities, remains unclear. Methods: This study examined how sensory modality modulates flanker interference under increasing WM loads. Twenty-two participants performed a visual n-back task at three load levels (1-, 2-, and 3-back) while ignoring visual (within-modality) or auditory (cross-modality) flankers. Results: Behaviorally, increased WM load (2- and 3-back) led to reduced accuracy (AC) and prolonged reaction times (RTs) in both conditions. In addition, flanker interference was observed under the 2-back condition in both the visual within-modality (VM) and audiovisual cross-modality (AVM) tasks. However, performance impairment emerged at a lower load (2-back) in the VM condition, whereas in the AVM condition, it only emerged at the highest load (3-back). Significant performance impairment in the AVM condition occurred at higher WM loads, suggesting that greater WM load is required to trigger interference. Event-related potential (ERP) results showed that N200 amplitudes increased significantly for incongruent flankers under the highest WM load (3-back) in the visual within-modality condition, reflecting greater inhibitory demands. In the cross-modality condition, enhanced N200 was not observed across all loads and even reversed at low load (1-back). Moreover, the results also showed that P300 amplitude increased with load in the within-modality condition but decreased in the cross-modality condition. Conclusions: These results demonstrated that the interaction between updating and inhibition is shaped by both WM load and sensory modality, further supporting a sensory modality-specific resource allocation mechanism. The cross-modality configurations may enable more efficient distribution of cognitive resources under high load, reducing interference between concurrent executive demands.No potential conflict of interest relevant to this article was reported.Frontiers Media SAActa Medica Okayama1662-453X192025Effects of visual spatial frequency on audiovisual interaction: an event-related potential study1599114ENFengxiaWuSchool of Artificial Intelligence, Changchun University of Science and TechnologyYannaRenDepartment of Psychology, College of Humanities and Management, Guizhou University of Traditional Chinese MedicineTengfeiHaoSchool of Artificial Intelligence, Changchun University of Science and TechnologyJingjingYangSchool of Artificial Intelligence, Changchun University of Science and TechnologyQiongWuDepartment of Psychology, Suzhou University of Science and TechnologyJiajiaYangCognitive Neuroscience Laboratory, Graduate School of Natural Science and Technology, Okayama UniversityMengWangSchool of Artificial Intelligence, Changchun University of Science and TechnologySpatial frequency is a fundamental characteristic of visual signals that modulates the audiovisual integration behavior, but the neural mechanisms underlying spatial frequency are not well established. In the present study, the high temporal resolution of event-related potentials was used to investigate how visual spatial frequency modulates audiovisual integration. A visual orientation discrimination task was used, and the spatial frequency of visual stimuli was manipulated under three conditions. Results showed that the influence of visual spatial frequency on audiovisual integration is a dynamic process. The earliest audiovisual integration occurred over the left temporal-occipital regions in the early sensory stage (60–90 ms) for high spatial frequency conditions but was absent for low and middle spatial frequency conditions. In addition, audiovisual integration over fronto-central regions was delayed as spatial frequency increased (from 230–260 ms to 260–320 ms). The integration effect was also observed over parietal and occipital regions at 350–380 ms, and its strength gradually decreased at higher spatial frequencies. These discrepancies in the temporal and spatial distributions of audiovisual integration imply that the role of spatial frequency varies between early sensory and late cognitive stages. The findings of this study offer the first neural demonstration that spatial frequency modulates audiovisual integration, thus providing a basis for studying complex multisensory integration, especially in semantic and emotional domains.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama0952-34803892025Ultrahigh‐Field MR‐Compatible Mechanical Tactile Stimulator for Investigating Somatosensory Processing in Small‐Bodied Animalse70105ENChenyuWangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityHirohikoImaiInnovation Research Center for Quantum Medicine, Gifu University School of MedicineMasakiFukunagaSection of Brain Function Information, National Institute for Physiological SciencesHirokiYamamotoGraduate School of Human and Environmental Studies, Kyoto UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityKazuhikoSekiDepartment of Neurophysiology, National Center of Neurology and PsychiatryTakashiHanakawaDepartment of Integrated Neuroanatomy and Neuroimaging, Kyoto University Graduate School of MedicineTatsuyaUmedaDepartment of Integrated Neuroanatomy and Neuroimaging, Kyoto University Graduate School of MedicineJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityCommon marmosets (Callithrix jacchus), small-bodied New World primates that share similar sensory processing pathways with human beings, have gained great interests. Their small body size allows imaging of brain activity with high spatial resolution and on a whole-brain scale using ultrahigh-field (UHF) magnetic resonance imaging (MRI) scanners. However, the strong magnetic field and the small size of the hand and forearm pose challenges in delivering tactile stimulation during fMRI experiments. In the present study, we developed an MR-compatible tactile dual-point stimulator to provide high-precision mechanical stimulation for exploring somatosensory processing in small-bodied animals. The study population consisted of a water phantom and three male common marmosets. Cerebral blood volume (CBV) weighted fMRI data were obtained with a gradient echo (GE), echo-planar imaging (EPI) sequence at 7T scanner. The output performance of the device was tested by a pressure sensor. The MR compatibility of the device was verified by measuring the temporal signal-to-noise ratio (tSNR) of a water phantom. To test the effectiveness of tactile stimulation, we conducted block designed tactile stimulation experiments on marmosets. A one-way repeated measures ANOVA was conducted for comparing the tSNR results. We performed one-sample t-tests to investigate the negative response of the forearm and hand stimulation with a threshold of t > 1.96 (p < 0.05). Performance tests revealed that mechanical stimulation (averaged force: 31.69 g) was applied with a delay of 12 ms. Phantom experiments confirmed that there was no significant difference in the tSNR among three (10 Hz, 1 Hz, and no-stimulus) conditions (F (2, 798) = 0.71, p = 0.49). The CBV activity results showed that the stimulator successfully elicited hand and forearm somatosensory activations in primary somatosensory areas. These results indicated that the device is well suited for small-bodied animal somatosensory studies.No potential conflict of interest relevant to this article was reported.岡山大学大学院ヘルスシステム統合科学研究科Acta Medica Okayama2436-322752025第16回 高度医療都市を創出する未来技術国際シンポジウム3537ENJiajiaYANGGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University10.18926/interdisciplinary/68624No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-328X1512025The Impact of Task Context on Pleasantness and Softness Estimations: A Study Based on Three Touch Strategies63ENBinyueGaoGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityThis study investigated the two distinct perceptions (pleasantness and softness) of deformable stimuli with different degrees of compliance under conditions with and without a contextual task. Three tactile strategies-grasping, pinching, and pressing-were used to perceive the stimuli. In Experiment 1 (without a contextual task), participants estimated the perceived intensity of softness or pleasantness for each stimulus. In Experiment 2 (with a contextual task), the participants sequentially perceived two stimuli with different compliance levels and indicated which stimulus they perceived as softer and pleasant. The results showed that the psychophysical relationship between compliance and perceived softness was consistent across all tactile strategies in both experiments, with softness estimates increasing as compliance increased. However, the relationship between compliance and pleasantness differed between the two experiments. In Experiment 1, pleasantness estimates increased monotonically with increased compliance. However, in Experiment 2, across all tactile strategies, pleasantness began to decrease within the compliance range of 0.25-2.0 cm2/N, exhibiting an inverted U-shaped trend. These findings indicate that the relationship between compliance and pleasantness is task-dependent, particularly demonstrating significantly different trends when a contextual task is introduced. In contrast, the relationship between compliance and softness remained consistently monotonic.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-342514122024The Impact of Selective Spatial Attention on Auditory-Tactile Integration: An Event-Related Potential Study1258ENWeichaoAnGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityNanZhangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityShengnanLiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityBackground: Auditory-tactile integration is an important research area in multisensory integration. Especially in special environments (e.g., traffic noise and complex work environments), auditory-tactile integration is crucial for human response and decision making. We investigated the influence of attention on the temporal course and spatial distribution of auditory-tactile integration. Methods: Participants received auditory stimuli alone, tactile stimuli alone, and simultaneous auditory and tactile stimuli, which were randomly presented on the left or right side. For each block, participants attended to all stimuli on the designated side and detected uncommon target stimuli while ignoring all stimuli on the other side. Event-related potentials (ERPs) were recorded via 64 scalp electrodes. Integration was quantified by comparing the response to the combined stimulus to the sum of the responses to the auditory and tactile stimuli presented separately. Results: The results demonstrated that compared to the unattended condition, integration occurred earlier and involved more brain regions in the attended condition when the stimulus was presented in the left hemispace. The unattended condition involved a more extensive range of brain regions and occurred earlier than the attended condition when the stimulus was presented in the right hemispace. Conclusions: Attention can modulate auditory-tactile integration and show systematic differences between the left and right hemispaces. These findings contribute to the understanding of the mechanisms of auditory-tactile information processing in the human brain.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-342514122024Contributions of the Primary Sensorimotor Cortex and Posterior Parietal Cortex to Motor Learning and Transfer1184ENChenyuWangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityBackground: Transferring learned manipulations to new manipulation tasks has enabled humans to realize thousands of dexterous object manipulations in daily life. Two-digit grasp and three-digit grasp manipulations require different fingertip forces, and our brain can switch grasp types to ensure good performance according to motor memory. We hypothesized that several brain areas contribute to the execution of the new type of motor according to the motor memory. However, the motor memory mechanisms during this transfer period are still unclear. In the present functional magnetic resonance imaging (fMRI) study, we aimed to investigate the cortical mechanisms involved in motor memory during the transfer phase of learned manipulation tasks. Methods: Using a custom-built T-shaped object with an adjustable weight distribution, the participants performed grasp and lift manipulation tasks under different conditions to simulate the learning and transfer phases. The learning phase consisted of four grasp-and-lift repetitions with one motor type, followed by a transfer phase with four repetitions involving different motors (adding or removing a digit). Results: By comparing brain activity in the learning and transfer phases, we identified three regions (the superior frontal gyrus, supramarginal gyrus, and postcentral gyrus) associated with motor memory during the transfer of learned manipulations. Conclusions: Our findings improve the understanding of the role of the posterior parietal cortex in motor memory, highlighting how sensory information from memory and real-time input is integrated to generate novel motor control signals that guide the precise reapplication of control strategies. Furthermore, we believe that these areas contribute to motor learning from motor memory and may serve as key regions of interest for investigating neurodegenerative diseases.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-34251452024Go/No-Go Ratios Modulate Inhibition-Related Brain Activity: An Event-Related Potential Study414ENNanZhangGraduate of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityWeichaoAnGraduate of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangGraduate of Interdisciplinary Science and Engineering in Health Systems, Okayama University(1) Background: Response inhibition refers to the conscious ability to suppress behavioral responses, which is crucial for effective cognitive control. Currently, research on response inhibition remains controversial, and the neurobiological mechanisms associated with response inhibition are still being explored. The Go/No-Go task is a widely used paradigm that can be used to effectively assess response inhibition capability. While many studies have utilized equal numbers of Go and No-Go trials, how different ratios affect response inhibition remains unknown; (2) Methods: This study investigated the impact of different ratios of Go and No-Go conditions on response inhibition using the Go/No-Go task combined with event-related potential (ERP) techniques; (3) Results: The results showed that as the proportion of Go trials decreased, behavioral performance in Go trials significantly improved in terms of response time, while error rates in No-Go trials gradually decreased. Additionally, the NoGo-P3 component at the central average electrodes (Cz, C1, C2, FCz, FC1, FC2, PCz, PC1, and PC2) exhibited reduced amplitude and latency; (4) Conclusions: These findings indicate that different ratios in Go/No-Go tasks influence response inhibition, with the brain adjusting processing capabilities and rates for response inhibition. This effect may be related to the brain's predictive mechanism model.No potential conflict of interest relevant to this article was reported.American Physiological SocietyActa Medica Okayama0022-307712752022Tactile angle discriminability improvement: contributions of working memory training and continuous attended sensory input13981406ENWuWangSchool of Psychological and Cognitive Sciences, Peking UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityHuazhiLiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYulongLiuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYiyangYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiabinYuCollege of Information Engineering, China Jiliang UniversityXiaoyuTangSchool of Psychology, Liaoning Collaborative Innovation Center of Children and Adolescents Healthy Personality Assessment and Cultivation, Liaoning Normal UniversityJingjingYangSchool of Computer Science and Technology, Changchun University of Science and TechnologySatoshiTakahashiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPerceptual learning is commonly assumed to enhance perception through continuous attended sensory input. However, learning is generalizable to performance in untrained stimuli and tasks. Although previous studies have observed a possible generalization effect across tasks as a result of working memory (WM) training, comparisons of the contributions of WM training and continuous attended sensory input to perceptual learning generalization are still rare. Therefore, we compared which factors contributed most to perceptual generalization and investigated which skills acquired during WM training led to tactile generalization across tasks. Here, a Braille-like dot pattern matching n-back WM task was used as the WM training task, with four workload levels (0, 1, 2, and 3-back levels). A tactile angle discrimination (TAD) task was used as a pre- and posttest to assess improvements in tactile perception. Between tests, four subject groups were randomly assigned to four different workload n-back tasks to consecutively complete three sessions of training. The results showed that tactile n-back WM training could enhance TAD performance, with the 3-back training group having the highest TAD threshold improvement rate. Furthermore, the rate of WM capacity improvement on the 3-back level across training sessions was correlated with the rate of TAD threshold improvement. These findings suggest that continuous attended sensory input and enhanced WM capacity can lead to improvements in TAD ability, and that greater improvements in WM capacity can predict greater improvements in TAD performance.<br>
NEW & NOTEWORTHY Perceptual learning is not always specific to the trained task and stimuli. We demonstrate that both continuous attended sensory input and improved WM capacity can be used to enhance tactile angle discrimination (TAD) ability. Moreover, WM capacity improvement is important in generalizing the training effect to the TAD ability. These findings contribute to understanding the mechanism of perceptual learning generalization across tasks.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama0014-481924032022Global surface features contribute to human haptic roughness estimations773789ENHuazhiLiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityWuWangSchool of Psychological and Cognitive Sciences, Peking UniversityYulongLiuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMengniZhouGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityQingqingLiDepartment of Teacher Education, Wenzhou UniversityJingjingYangSchool of Computer Science and Technology, Changchun University of Science and TechnologyShipingShaoSchool of Social Welfare, Yonsei UniversitySatoshiTakahashiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPrevious studies have paid special attention to the relationship between local features (e.g., raised dots) and human roughness perception. However, the relationship between global features (e.g., curved surface) and haptic roughness perception is still unclear. In the present study, a series of roughness estimation experiments was performed to investigate how global features affect human roughness perception. In each experiment, participants were asked to estimate the roughness of a series of haptic stimuli that combined local features (raised dots) and global features (sinusoidal-like curves). Experiments were designed to reveal whether global features changed their haptic roughness estimation. Furthermore, the present study tested whether the exploration method (direct, indirect, and static) changed haptic roughness estimations and examined the contribution of global features to roughness estimations. The results showed that sinusoidal-like curved surfaces with small periods were perceived to be rougher than those with large periods, while the direction of finger movement and indirect exploration did not change this phenomenon. Furthermore, the influence of global features on roughness was modulated by local features, regardless of whether raised-dot surfaces or smooth surfaces were used. Taken together, these findings suggested that an object’s global features contribute to haptic roughness perceptions, while local features change the weight of the contribution that global features make to haptic roughness perceptions.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-34251372023Audiovisual n-Back Training Alters the Neural Processes of Working Memory and Audiovisual Integration: Evidence of Changes in ERPs992ENAoGuoCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityWeipingYangDepartment of Psychology, Faculty of Education, Hubei UniversityXiangfuYangDepartment of Psychology, Faculty of Education, Hubei UniversityJinfeiLinDepartment of Psychology, Faculty of Education, Hubei UniversityZimoLiCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYannaRenDepartment of Psychology, College of Humanities and Management, Guizhou University of Traditional Chinese MedicineJiajiaYangCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University(1) Background: This study investigates whether audiovisual n-back training leads to training effects on working memory and transfer effects on perceptual processing. (2) Methods: Before and after training, the participants were tested using the audiovisual n-back task (1-, 2-, or 3-back), to detect training effects, and the audiovisual discrimination task, to detect transfer effects. (3) Results: For the training effect, the behavioral results show that training leads to greater accuracy and faster response times. Stronger training gains in accuracy and response time using 3- and 2-back tasks, compared to 1-back, were observed in the training group. Event-related potentials (ERPs) data revealed an enhancement of P300 in the frontal and central regions across all working memory levels after training. Training also led to the enhancement of N200 in the central region in the 3-back condition. For the transfer effect, greater audiovisual integration in the frontal and central regions during the post-test rather than pre-test was observed at an early stage (80-120 ms) in the training group. (4) Conclusion: Our findings provide evidence that audiovisual n-back training enhances neural processes underlying a working memory and demonstrate a positive influence of higher cognitive functions on lower cognitive functions.No potential conflict of interest relevant to this article was reported.Frontiers in PsychologyActa Medica Okayama1664-1078142023Auditory affective content facilitates time-to-contact estimation of visual affective targets1105824ENFeifeiLuDepartment of Psychology, Research Center for Psychology and Behavioral Sciences, Soochow UniversityYouLiCollege of Chinese Language and Culture, Jinan UniversityJiajiaYangApplied Brain Science Lab, Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityAijunWangDepartment of Psychology, Research Center for Psychology and Behavioral Sciences, Soochow UniversityMingZhangCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityReacting to a moving object requires an ability to estimate when a moving object reaches its destination, also referred to as the time-to-contact (TTC) estimation. Although the TTC estimation of threatening visually moving objects is known to be underestimated, the effect of the affective content of auditory information on visual TTC estimation remains unclear. We manipulated the velocity and presentation time to investigate the TTC of a threat or non-threat target with the addition of auditory information. In the task, a visual or an audiovisual target moved from right to left and disappeared behind an occluder. Participants' task was to estimate the TTC of the target, they needed to press a button when they thought that the target contacted a destination behind the occluder. Behaviorally, the additional auditory affective content facilitated TTC estimation; velocity was a more critical factor than presentation time in determining the audiovisual threat facilitation effect. Overall, the results indicate that exposure to auditory affective content can influence TTC estimation and that the effect of velocity on TTC estimation will provide more information than presentation time.No potential conflict of interest relevant to this article was reported.Frontiers Media SAActa Medica Okayama1664-1078132022Subliminal meaning-contingent attentional orienting: The role of attentional control setting based on displaywide features1035690ENHuiyuanWangDepartment of Psychology, Jilin UniversityJiajiaYangFaculty of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYulinGaoDepartment of Psychology, Jilin UniversityMingZhangFaculty of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPeople's subjective factors can affect the spatial allocation of attention, and objects that are more in line with people's expectations are easier to attract attention. In the current study, we wanted to know whether the meaning-contingent spatial attentional orienting could occur at the subliminal level, that is, whether conscious awareness was needed, and which attentional control settings worked. The current study employed a modified spatial cueing paradigm and the cues were made imperceptible by backward masking. The results showed that the capture effects of the left and the right positions stemmed from the meaning-contingent attentional control setting based on displaywide features, while the inhibition effect of the lower position and the capture effect of the upper position stemmed from the abrupt onset of subliminal cues and their masks. It is concluded that the attentional orienting of meaning contingency could occur at the subliminal level, which was not restricted by conscious perception. In particular, the attentional control setting based on displaywide features played an important role in spatial attentional orienting, which was manifested in the consistent capture effects on the horizontal sides. This study refined and separated the spatial attentional orienting effects, supported the contingent involuntary attentional orienting hypothesis, and expanded its scope of application.No potential conflict of interest relevant to this article was reported.Academic Press Inc. Elsevier ScienceActa Medica Okayama1053-81192482022Layer-specific activation in human primary somatosensory cortex during tactile temporal prediction error processing118867ENYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityLaurentiusHuberMR-Methods Group, MBIC, Cognitive Neuroscience Department, Faculty of Psychology and Neuroscience, University of Maastricht, Cognitive NeuroscienceJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityMasakiFukunagaDivision of Cerebral Research, National Institute for Physiological SciencesYuhuiChaiSection on Functional Imaging Methods, National Institute of Mental HealthDavid C.JangrawSection on Functional Imaging Methods, National Institute of Mental HealthGangChenScientific and Statistical Computational Core, National Institute of Mental HealthDaniel A.HandwerkerSection on Functional Imaging Methods, National Institute of Mental HealthPeter J.MolfeseSection on Functional Imaging Methods, National Institute of Mental HealthYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityNorihiroSadatoDivision of Cerebral Research, National Institute for Physiological SciencesJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPeter A.BandettiniSection on Functional Imaging Methods, National Institute of Mental HealthThe human brain continuously generates predictions of incoming sensory input and calculates corresponding prediction errors from the perceived inputs to update internal predictions. In human primary somatosensory cortex (area 3b), different cortical layers are involved in receiving the sensory input and generation of error signals. It remains unknown, however, how the layers in the human area 3b contribute to the temporal prediction error processing. To investigate prediction error representation in the area 3b across layers, we acquired layer specific functional magnetic resonance imaging (fMRI) data at 7T from human area 3b during a task of index finger poking with no-delay, short-delay and long-delay touching sequences. We demonstrate that all three tasks increased activity in both superficial and deep layers of area 3b compared to the random sensory input. The fMRI signal was differentially modulated solely in the deep layers rather than the superficial layers of area 3b by the delay time. Compared with the no-delay stimuli, activity was greater in the deep layers of area 3b during the short delay stimuli but lower during the long-delay stimuli. This difference activity features in the superficial and deep layers suggest distinct functional contributions of area 3b layers to tactile temporal prediction error processing. The functional segregation in area 3b across layers may reflect that the excitatory and inhibitory interplay in the sensory cortex contributions to flexible communication between cortical layers or between cortical areas.No potential conflict of interest relevant to this article was reported.Elsevier BVActa Medica Okayama0149-76341282021Linking cortical circuit models to human cognition with laminar fMRI467478ENJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityLaurentiusHuberMR-Methods Group, Faculty of Psychology and Neuroscience, University of MaastrichtYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPeter A.BandettiniSection on Functional Imaging Methods, National Institute of Mental HealthLaboratory animal research has provided significant knowledge into the function of cortical circuits at the laminar level, which has yet to be fully leveraged towards insights about human brain function on a similar spatiotemporal scale. The use of functional magnetic resonance imaging (fMRI) in conjunction with neural models provides new opportunities to gain important insights from current knowledge. During the last five years, human studies have demonstrated the value of high-resolution fMRI to study laminar-specific activity in the human brain. This is mostly performed at ultra-high-field strengths (≥ 7 T) and is known as laminar fMRI. Advancements in laminar fMRI are beginning to open new possibilities for studying questions in basic cognitive neuroscience. In this paper, we first review recent methodological advances in laminar fMRI and describe recent human laminar fMRI studies. Then, we discuss how the use of laminar fMRI can help bridge the gap between cortical circuit models and human cognition.No potential conflict of interest relevant to this article was reported.MDPIActa Medica Okayama2076-341711152021A New Method for Haptic Shape Discriminability Detection7049ENYulongLiuCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYiyangYuCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityWuWangThe School of Psychological and Cognitive Sciences, Peking UniversityHuazhiLiCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversitySatoshiTakahashiCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoshimichiEjimaCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityQiongWuDepartment of Psychology, Suzhou University of Science and Technology,JinglongWuResearch Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of SciencesTouch shape discrimination is not only closely related to tactile mechanoreceptors but also higher cognitive function. However, previous shape discrimination methods are difficult to complete in a short time, and the devices are complicated to operate and not user-friendly for nonprofessionals. Here, we propose a new method, the evaluation quantity of which is the angle discrimination threshold. In addition, to make this method easy to use for nonprofessionals, we designed a haptic angle sorting system, including the device and software. To evaluate this method, the angle sorting and two-angle discrimination experiments were compared, and it was found that participants spent significantly less time in the former experiment than in the latter. At the same time, there is a strong correlation between the performance of angle sorting and two-angle discrimination, which shows that the angle threshold obtained by the new method can also be used to evaluate the ability of touch discrimination. Moreover, the angle sorting results of different age groups also further demonstrate the feasibility of the method. The efficiency of this new method and the effectiveness of the system also provide a convenient means for evaluating haptic shape discrimination, which may have potential clinical application value in the early diagnosis of peripheral neuropathy and even in the evaluation of cognitive function.No potential conflict of interest relevant to this article was reported.Academic Press Inc Elsevier ScienceActa Medica Okayama1053-81192312021Different activation signatures in the primary sensorimotor and higher-level regions for haptic three-dimensional curved surface exploration117754ENJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPeter J.MolfeseSection on Functional Imaging Methods, National Institute of Mental HealthYinghuaYuSection on Functional Imaging Methods, National Institute of Mental HealthDaniel A.HandwerkerSection on Functional Imaging Methods, National Institute of Mental HealthGangChenScientific and Statistical Computational Core, National Institute of Mental HealthPaul A.TaylorScientific and Statistical Computational Core, National Institute of Mental HealthYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPeter A.BandettiniSection on Functional Imaging Methods, National Institute of Mental HealthHaptic object perception begins with continuous exploratory contact, and the human brain needs to accumulate sensory information continuously over time. However, it is still unclear how the primary sensorimotor cortex (PSC) interacts with these higher-level regions during haptic exploration over time. This functional magnetic resonance imaging (fMRI) study investigates time-dependent haptic object processing by examining brain activity during haptic 3D curve and roughness estimations. For this experiment, we designed sixteen haptic stimuli (4 kinds of curves x 4 varieties of roughness) for the haptic curve and roughness estimation tasks. Twenty participants were asked to move their right index and middle fingers along the surface twice and to estimate one of the two features -roughness or curvature -depending on the task instruction. We found that the brain activity in several higher-level regions (e.g., the bilateral posterior parietal cortex) linearly increased as the number of curves increased during the haptic exploration phase. Surprisingly, we found that the contralateral PSC was parametrically modulated by the number of curves only during the late exploration phase but not during the early exploration phase. In contrast, we found no similar parametric modulation activity patterns during the haptic roughness estimation task in either the contralateral PSC or in higher-level regions. Thus, our findings suggest that haptic 3D object perception is processed across the cortical hierarchy, whereas the contralateral PSC interacts with other higher-level regions across time in a manner that is dependent upon the features of the object.No potential conflict of interest relevant to this article was reported.SAGE PublicationsActa Medica Okayama2041-66951162020Semantic Congruency Modulates the Effect of Attentional Load on the Audiovisual Integration of Animate Images and Sounds2041669520981096ENQingqingLiCognitive Neuroscience Laboratory, Graduate School of Natural Science and Technology, Okayama UniversityQiongWuDepartment of Psychology, Suzhou University of Science and TechnologyYiyangYuCognitive Neuroscience Laboratory, Graduate School of Natural Science and Technology, Okayama UniversityFengxiaWuCognitive Neuroscience Laboratory, Graduate School of Natural Science and Technology, Okayama UniversitySatoshiTakahashiCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoshimichiEjimaCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiajiaYangCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuCognitive Neuroscience Laboratory, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityAttentional processes play a complex and multifaceted role in the integration of input from different sensory modalities. However, whether increased attentional load disrupts the audiovisual (AV) integration of common objects that involve semantic content remains unclear. Furthermore, knowledge regarding how semantic congruency interacts with attentional load to influence the AV integration of common objects is limited. We investigated these questions by examining AV integration under various attentional-load conditions. AV integration was assessed by adopting an animal identification task using unisensory (animal images and sounds) and AV stimuli (semantically congruent AV objects and semantically incongruent AV objects), while attentional load was manipulated by using a rapid serial visual presentation task. Our results indicate that attentional load did not attenuate the integration of semantically congruent AV objects. However, semantically incongruent animal sounds and images were not integrated (as there was no multisensory facilitation), and the interference effect produced by the semantically incongruent AV objects was reduced by increased attentional-load manipulations. These findings highlight the critical role of semantic congruency in modulating the effect of attentional load on the AV integration of common objects.No potential conflict of interest relevant to this article was reported.Frontiers MediaActa Medica Okayama1662-5196142021Stimulus Intervals Modulate the Balance of Brain Activity in the Human Primary Somatosensory Cortex: An ERP Study571369ENYangLiuDepartment of Psychology, Suzhou University of Science and TechnologyBoDongDepartment of Psychology, Suzhou University of Science and TechnologyJiajiaYangCognitive Neuroscience Laboratory, Graduate School of Natural Science and Technology, Okayama UniversityYoshimichiEjimaCognitive Neuroscience Laboratory, Graduate School of Natural Science and Technology, Okayama UniversityJinglongWuCognitive Neuroscience Laboratory, Graduate School of Natural Science and Technology, Okayama UniversityQiongWuCognitive Neuroscience Laboratory, Graduate School of Natural Science and Technology, Okayama UniversityMingZhangCognitive Neuroscience Laboratory, Graduate School of Natural Science and Technology, Okayama UniversityNeuronal excitation and inhibition occur in the brain at the same time, and brain activation reflects changes in the sum of excitation and inhibition. This principle has been well-established in lower-level sensory systems, including vision and touch, based on animal studies. However, it is unclear how the somatosensory system processes the balance between excitation and inhibition. In the present ERP study, we modified the traditional spatial attention paradigm by adding double stimuli presentations at short intervals (i.e., 10, 30, and 100 ms). Seventeen subjects participated in the experiment. Five types of stimulation were used in the experiment: a single stimulus (one raised pin for 40 ms), standard stimulus (eight pins for 40 ms), and double stimuli presented at intervals of 10, 30, and 100 ms. The subjects were asked to attend to a particular finger and detect whether the standard stimulus was presented to that finger. The results showed a clear attention-related ERP component in the single stimulus condition, but the suppression components associated with the three interval conditions seemed to be dominant in somatosensory areas. In particular, we found the strongest suppression effect in the ISI-30 condition (interval of 30 ms) and that the suppression and enhancement effects seemed to be counterbalanced in both the ISI-10 and ISI-100 conditions (intervals of 10 and 100 ms, respectively). This type of processing may allow humans to easily discriminate between multiple stimuli on the same body part.No potential conflict of interest relevant to this article was reported.WileyActa Medica Okayama2162-32791132021Functional heterogeneity in the left lateral posterior parietal cortex during visual and haptic crossmodal dot-surface matchinge02033ENJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYinghuaYuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityHiroakiShigemasuKochi University of TechnologyHiroshiKadotaKochi University of TechnologyKiyoshiNakaharaKochi University of TechnologyTakanoriKochiyamaATR Brain Activity Imaging CenterYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityBackground</br>
Vision and touch are thought to contribute information to object perception in an independent but complementary manner. The left lateral posterior parietal cortex (LPPC) has long been associated with multisensory information processing, and it plays an important role in visual and haptic crossmodal information retrieval. However, it remains unclear how LPPC subregions are involved in visuo‐haptic crossmodal retrieval processing.</br>
Methods</br>
In the present study, we used an fMRI experiment with a crossmodal delayed match‐to‐sample paradigm to reveal the functional role of LPPC subregions related to unimodal and crossmodal dot‐surface retrieval.</br>
Results</br>
The visual‐to‐haptic condition enhanced the activity of the left inferior parietal lobule relative to the haptic unimodal condition, whereas the inverse condition enhanced the activity of the left superior parietal lobule. By contrast, activation of the left intraparietal sulcus did not differ significantly between the crossmodal and unimodal conditions. Seed‐based resting connectivity analysis revealed that these three left LPPC subregions engaged distinct networks, confirming their different functions in crossmodal retrieval processing.</br>
Conclusion</br>
Taken together, the findings suggest that functional heterogeneity of the left LPPC during visuo‐haptic crossmodal dot‐surface retrieval processing reflects that the left LPPC does not simply contribute to retrieval of past information; rather, each subregion has a specific functional role in resolving different task requirements.No potential conflict of interest relevant to this article was reported.American Physiological SocietyActa Medica Okayama0022-307712252019Tactile angle discriminability improvement: roles of training time intervals and different types of training tasks19181927ENWuWangGraduate School of Natural Science and Technology, Okayama UniversityJiajiaYangGraduate School of Interdisciplinary Science and Engineering in Health Systems, OkayamaQiongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJiabinYu Graduate School of Natural Science and Technology, Okayama UniversitySatoshiTakahashiGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityYoshimichiEjimaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityJinglongWuGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityPerceptual learning, which is not limited to sensory modalities such as vision and touch, emerges within a training session and between training sessions and is accompanied by the remodeling of neural connections in the cortex. However, limited knowledge exists regarding perceptual learning between training sessions. Although tactile studies have paid attention to between-session learning effects, there have been few studies asking fundamental questions regarding whether the time interval between training sessions affects tactile perceptual learning and generalization across tactile tasks. We investigated the effects of different training time intervals on the consecutive performance of a tactile angle discrimination (AD) task and a tactile orientation discrimination (OD) task training on tactile angle discriminability. The results indicated that in the short-interval training group, AD task performance significantly improved in the early stage of learning and nearly plateaued in the later stage, whereas in the long-interval training group, significant improvement was delayed and then also nearly plateaued in the later stage; additionally, improved OD task performance resulted in improved AD task performance. These findings suggest that training time interval affects the early stage of learning but not the later stage and that generalization occurs between different types of tactile tasks.No potential conflict of interest relevant to this article was reported.