Perceptual Uncertainty Alternates Top-down and Bottom-up Fronto-Temporal Network Signaling during Response Inhibition.

Response inhibition is a primary executive control function that allows the withholding of inappropriate responses, and requires appropriate perception of the external environment to achieve a behavioral goal. It remains unclear, however, how response inhibition is achieved when goal-relevant information involves perceptual uncertainty. Twenty-six human participants of both sexes performed a go/no-go task where visually presented random-dot motion stimuli involved perceptual uncertainties. The right inferior frontal cortex (rIFC) was involved in response inhibition, and the middle temporal (MT) region showed greater activity when dot motions involved less uncertainty. A neocortical temporal region in the superior temporal sulcus (STS) specifically showed greater activity during response inhibition in more perceptually certain trials. In this STS region, activity was greater when response inhibition was successful than when it failed. Directional effective connectivity analysis revealed that, in more coherent trials, the MT and STS regions showed enhanced connectivity to the rIFC, whereas in less coherent trials, the signal direction was reversed. These results suggest that a reversible fronto-temporal functional network guides response inhibition and perceptual decision-making under perceptual uncertainty, and in this network, perceptual information in the MT is converted to control information in the rIFC via STS, enabling achievement of response inhibition.SIGNIFICANCE STATEMENT Response inhibition refers to withholding inappropriate behavior and is important for achieving goals. Often, however, decision must be made based on limited environmental evidence. We showed that successful response inhibition is guided by a neocortical temporal region that plays a hub role in converting perceived information coded in a posterior temporal region to control information coded in the PFC. Interestingly, when a perceived stimulus becomes more uncertain, the PFC supplements stimulus encoding in the temporal regions. Our results highlight fronto-temporal mechanisms of response inhibition in which conversion of stimulus-control information is regulated based on the uncertainty of environmental evidence.

Multimodal deep neural decoding reveals highly resolved spatiotemporal profile of visual object representation in humans.

Perception and categorization of objects in a visual scene are essential to grasp the surrounding situation. Recently, neural decoding schemes, such as machine learning in functional magnetic resonance imaging (fMRI), has been employed to elucidate the underlying neural mechanisms. However, it remains unclear as to how spatially distributed brain regions temporally represent visual object categories and sub-categories. One promising strategy to address this issue is neural decoding with concurrently obtained neural response data of high spatial and temporal resolution. In this study, we explored the spatial and temporal organization of visual object representations using concurrent fMRI and electroencephalography (EEG), combined with neural decoding using deep neural networks (DNNs). We hypothesized that neural decoding by multimodal neural data with DNN would show high classification performance in visual object categorization (faces or non-face objects) and sub-categorization within faces and objects. Visualization of the fMRI DNN was more sensitive than that in the univariate approach and revealed that visual categorization occurred in brain-wide regions. Interestingly, the EEG DNN valued the earlier phase of neural responses for categorization and the later phase of neural responses for sub-categorization. Combination of the two DNNs improved the classification performance for both categorization and sub-categorization compared with fMRI DNN or EEG DNN alone. These deep learning-based results demonstrate a categorization principle in which visual objects are represented in a spatially organized and coarse-to-fine manner, and provide strong evidence of the ability of multimodal deep learning to uncover spatiotemporal neural machinery in sensory processing.

Reversible Fronto-occipitotemporal Signaling Complements Task Encoding and Switching under Ambiguous Cues.

Adaptation to changing environments involves the appropriate extraction of environmental information to achieve a behavioral goal. It remains unclear how behavioral flexibility is guided under situations where the relevant behavior is ambiguous. Using functional brain mapping of machine learning decoders and directional functional connectivity, we show that brain-wide reversible neural signaling underpins task encoding and behavioral flexibility in ambiguously changing environments. When relevant behavior is cued ambiguously during behavioral shifting, neural coding is attenuated in distributed cortical regions, but top-down signals from the prefrontal cortex complement the coding. When behavioral shifting is cued more explicitly, modality-specialized occipitotemporal regions implement distinct neural coding about relevant behavior, and bottom-up signals from the occipitotemporal region to the prefrontal cortex supplement the behavioral shift. These results suggest that our adaptation to an ever-changing world is orchestrated by the alternation of top-down and bottom-up signaling in the fronto-occipitotemporal circuit depending on the availability of environmental information.

Cross-Hemispheric Complementary Prefrontal Mechanisms during Task Switching under Perceptual Uncertainty.

Flexible adaptation to changing environments is a representative executive control function implicated in the frontoparietal network that requires appropriate extraction of goal-relevant information through perception of the external environment. It remains unclear, however, how the flexibility is achieved under situations where goal-relevant information is uncertain. To address this issue, the current study examined neural mechanisms for task switching in which task-relevant information involved perceptual uncertainty. Twenty-eight human participants of both sexes alternated behavioral tasks in which they judged motion direction or color of visually presented colored dot stimuli that moved randomly. Task switching was associated with frontoparietal regions in the left hemisphere, and perception of ambiguous stimuli involved contralateral homologous frontoparietal regions. On the other hand, in stimulus-modality-dependent occipitotemporal regions, task coding information was increased during task switching. Effective connectivity analysis revealed that the frontal regions signaled toward the modality-dependent occipitotemporal regions when a relevant stimulus was more ambiguous, whereas the occipitotemporal regions signaled toward the frontal regions when the stimulus was more distinctive. These results suggest that complementary prefrontal mechanisms in the left and right hemispheres help to achieve a behavioral goal when the external environment involves perceptual uncertainty.SIGNIFICANCE STATEMENT In our daily life, environmental information to achieve a goal is not always certain, but we make judgments in such situations, and change our behavior accordingly. This study examined how the flexibility of behavior is achieved in a situation where goal-relevant information involves perceptual uncertainty. fMRI revealed that the lateral prefrontal cortex (PFC) in the left hemisphere is associated with behavioral flexibility, and the perception of ambiguous stimuli involves the PFC in the right hemisphere. These bilateral PFC signaled to stimulus-modality-dependent occipitotemporal regions, depending on perceptual uncertainty and the task to be performed. These top-down signals supplement task coding in the occipitotemporal regions, and highlight interhemispheric prefrontal mechanisms involved in executive control and perceptual decision-making.

Executive control by fronto-parietal activity explains counterintuitive decision behavior in complex value-based decision-making.

In real life, humans make decisions by taking into account multiple independent factors, such as delay and probability. Cognitive psychology suggests that cognitive control mechanisms play a key role when facing such complex task conditions. However, in value-based decision-making, it still remains unclear to what extent cognitive control mechanisms become essential when the task condition is complex. In this study, we investigated decision-making behaviors and underlying neural mechanisms using a multifactor gambling task where participants simultaneously considered probability and delay. Decision-making behavior in the multifactor task was modulated by both probability and delay. The behavioral effect of probability was stronger than delay, consistent with previous studies. Furthermore, in a subset of conditions that recruited fronto-parietal activations, reaction times were paradoxically elongated despite lower probabilistic uncertainty. Notably, such a reaction time elongation did not occur in control tasks involving single factors. Meta-analysis of brain activations suggested an interpretation that the paradoxical increase of reaction time may be associated with strategy switching. Consistent with this interpretation, logistic regression analysis of the behavioral data suggested a presence of multiple decision strategies. Taken together, we found that a novel complex value-based decision-making task cause prominent activations in fronto-parietal cortex. Furthermore, we propose that these activations can be interpreted as recruitment of cognitive control system in complex situations.

Self-Controlled Choice Arises from Dynamic Prefrontal Signals That Enable Future Anticipation.

Self-control allows humans the patience necessary to maximize reward attainment in the future. Yet it remains elusive when and how the preference to self-controlled choice is formed. We measured brain activity while female and male humans performed an intertemporal choice task in which they first received delayed real liquid rewards (forced-choice trial), and then made a choice between the reward options based on the experiences (free-choice trial). We found that, while subjects were awaiting an upcoming reward in the forced-choice trial, the anterior prefrontal cortex (aPFC) tracked a dynamic signal reflecting the pleasure of anticipating the future reward. Importantly, this prefrontal signal was specifically observed in self-controlled individuals, and moreover, interregional negative coupling between the prefrontal region and the ventral striatum (VS) became stronger in those individuals. During consumption of the liquid rewards, reduced ventral striatal activity predicted self-controlled choices in the subsequent free-choice trials. These results suggest that a well-coordinated prefrontal-striatal mechanism during the reward experience shapes preferences regarding the future self-controlled choice.SIGNIFICANCE STATEMENT Anticipating future desirable events is a critical mental function that guides self-controlled behavior in humans. When and how are the self-controlled choices formed in the brain? We monitored brain activity while humans awaited a real liquid reward that became available in tens of seconds. We found that the frontal polar cortex tracked temporally evolving signals reflecting the pleasure of anticipating the future reward, which was enhanced in self-controlled individuals. Our results highlight the contribution of the fronto-polar cortex to the formation of self-controlled preferences, and further suggest that future prospect in the prefrontal cortex (PFC) plays an important role in shaping future choice behavior.

Freestyle gymnastic exercise can be used to assess complex coordination in a variety of sports.

OBJECTIVE: The assessment of motor coordination is a very complex process and demonstrates a high degree of sport specificity. There are a limited number of tests, if any, where results correlate with the success rate of athletes in different sports. METHODS: Free style gymnastic exercise (FSGE) and coordination ball dribbling exercise (CBDE) were used to see whether the execution quality of these tests is related to the quality of athletes from team handball, water polo, kayak, rhythmical gymnastics (RG) and aerobics (222 athletes - 75 male, 147 female; 23 non-athletes - 9 male, 14 female). RESULTS: FSGE results related to the quality of performance in all sports (r = -0.232, p < 0.01 in handball, water polo, kayak and r = -0.26, p < 0.05 in aerobics and RG), while CBDE did not. Older players had higher ranking as they had more time to be successful at their sport (r = -0.498, p < 0.01 in handball, water polo, kayak; r = -0.298, p < 0.05 in aerobics and RG). The scores of FSGE were independent from the age and gender of the subjects. CONCLUSIONS: The main findings were: (i) that athletes did significantly better than the controls in both tests; (ii) RG and aerobics athletes did better on the FSGE than handball, water polo players and kayakers; (iii) handball players did better than kayakers, RG and aerobics athletes on the CBDE test; and (iv) better ranked athletes performed better on the FGSE test. Therefore, FSGE test appears to be a reliable test to assess coordination in variety of sport and different levels of sport performance.

Photoconductive Properties of Dibenzotetrathiafulvalene-Tetracyanoquinodimethane (DBTTF-TCNQ) Nanorods Prepared by the Reprecipitation Method.

Charge-transfer complex crystals have been extensively studied because of their metallic conductivity, photoconductivity, ambipolar charge transport, and high career mobility. Numerous studies of their applications for organic electric devices such as organic field effect transistors and solar cells have reported. However, bulky single crystals of charge-transfer complexes are difficult to handle, specifically to be made into a form of a thin film. Recently, nano/micro crystallization of charge-transfer crystal is attracted to realize thin film applications. In this paper, charge transfer complex nanorods composed of dibenzotetrathiafulvalene-tetracyanoquinodimethane (DBTTF-TCNQ) were prepared by the reprecipitation method. The as-formed nanorods possess a kinetically metastable crystal structure different from the thermodynamically stable bulk crystal prepared by slow evaporation of the solvent. From photoconductive measurement, nanorod stacks show a significant photosensitivity (354.57 µA/W) on par with bulk crystal (417.14 µA/W). These results suggest dibenzotetrathiafulvalene-tetracyanoquinodimethane (DBTTF-TCNQ) nanorods have a favorable crystal structure for carrier transport due to the difference of molecular stacking assembly.

Cross-Country Skiing Analysis and Ski Technique Detection by High-Precision Kinematic Global Navigation Satellite System.

Cross-country skiing (XCS) embraces a broad variety of techniques applied like a gear system according to external conditions, slope topography, and skier-related factors. The continuous detection of applied skiing techniques and cycle characteristics by application of unobtrusive sensor technology can provide useful information to enhance the quality of training and competition. (1) Background: We evaluated the possibility of using a high-precision kinematic global navigation satellite system (GNSS) to detect cross-country skiing classical style technique. (2) Methods: A world-class male XC skier was analyzed during a classical style 5.3-km time trial recorded with a high-precision kinematic GNSS attached to the skier's head. A video camera was mounted on the lumbar region of the skier to detect the type and number of cycles of each technique used during the entire time trial. Based on the GNSS trajectory, distinct patterns of head displacement (up-down head motion) for each classical technique (e.g., diagonal stride (DIA), double poling (DP), kick double poling (KDP), herringbone (HB), and downhill) were defined. The applied skiing technique, skiing duration, skiing distance, skiing speed, and cycle time within a technique and the number of cycles were visually analyzed using both the GNSS signal and the video data by independent persons. Distinct patterns for each technique were counted by two methods: Head displacement with course inclination and without course inclination (net up-down head motion). (3) Results: Within the time trial, 49.6% (6 min, 46 s) was DP, 18.7% (2 min, 33 s) DIA, 6.1% (50 s) KDP, 3.3% (27 s) HB, and 22.3% (3 min, 03 s) downhill with respect to total skiing time (13 min, 09 s). The %Match for both methods 1 and 2 (net head motion) was high: 99.2% and 102.4%, respectively, for DP; 101.7% and 95.9%, respectively, for DIA; 89.4% and 100.0%, respectively, for KDP; 86.0% and 96.5%, respectively, in HB; and 98.6% and 99.6%, respectively, in total. (4) Conclusions: Based on the results of our study, it is suggested that a high-precision kinematic GNSS can be applied for precise detection of the type of technique, and the number of cycles used, duration, skiing speed, skiing distance, and cycle time for each technique, during a classical style XCS race.

Distinct neuronal interactions in anterior inferotemporal areas of macaque monkeys during retrieval of object association memory.

In macaque monkeys, the anterior inferotemporal cortex, a region crucial for object memory processing, is composed of two adjacent, hierarchically distinct areas, TE and 36, for which different functional roles and neuronal responses in object memory tasks have been characterized. However, it remains unknown how the neuronal interactions differ between these areas during memory retrieval. Here, we conducted simultaneous recordings from multiple single-units in each of these areas while monkeys performed an object association memory task and examined the inter-area differences in neuronal interactions during the delay period. Although memory neurons showing sustained activity for the presented cue stimulus, cue-holding (CH) neurons, interacted with each other in both areas, only those neurons in area 36 interacted with another type of memory neurons coding for the to-be-recalled paired associate (pair-recall neurons) during memory retrieval. Furthermore, pairs of CH neurons in area TE showed functional coupling in response to each individual object during memory retention, whereas the same class of neuron pairs in area 36 exhibited a comparable strength of coupling in response to both associated objects. These results suggest predominant neuronal interactions in area 36 during the mnemonic processing, which may underlie the pivotal role of this brain area in both storage and retrieval of object association memory.

Mitochondrial biogenesis-associated factors underlie the magnitude of response to aerobic endurance training in rats.

Trainability is important in elite sport and in recreational physical activity, and the wide range for response to training is largely dependent on genotype. In this study, we compare a newly developed rat model system selectively bred for low and high gain in running distance from aerobic training to test whether genetic segregation for trainability associates with differences in factors associated with mitochondrial biogenesis. Low response trainer (LRT) and high response trainer (HRT) rats from generation 11 of artificial selection were trained five times a week, 30 min per day for 3 months at 70 % VO2max to study the mitochondrial molecular background of trainability. As expected, we found significant differential for the gain in running distance between LRT and HRT groups as a result of training. However, the changes in VO2max, COX-4, redox homeostasis associated markers (reactive oxygen species (ROS)), silent mating-type information regulation 2 homolog (SIRT1), NAD(+)/NADH ratio, proteasome (R2 subunit), and mitochondrial network related proteins such as mitochondrial fission protein 1 (Fis1) and mitochondrial fusion protein (Mfn1) suggest that these markers are not strongly involved in the differences in trainability between LRT and HRT. On the other hand, according to our results, we discovered that differences in basal activity of AMP-activated protein kinase alpha (AMPKα) and differential changes in aerobic exercise-induced responses of citrate synthase, carbonylated protein, peroxisome proliferator-activated receptor gamma coactivator-1α (PGC1-α), nuclear respiratory factor 1 (NRF1), mitochondrial transcription factor A (TFAM), and Lon protease limit trainability between these selected lines. From this, we conclude that mitochondrial biogenesis-associated factors adapt differently to aerobic exercise training in training sensitive and training resistant rats.

A case of ascending aortic dissection and rupture caused by giant cell arteritis.

Giant cell arteritis (GCA) is an autoimmune disease characterized by granulomatous inflammation in the wall of medium-sized and large-sized arteries, and it usually occurs in patients over 50 years of age.(1)) Symptoms are nonspecific, and include fatigue, fever, and headache.(2)) It is occasionally combined with aortic complications, and ruptures resulting in death. These complications occur as late events, usually several years after diagnosis and often after other symptoms have subsided.(3)) Physicians should therefore be alert for complications of the large arteries in GCA. Here we present a case of GCA combined with ascending aortic dissection and rupture 3 weeks after diagnosis.

The effects of cold water immersion after rugby training on muscle power and biochemical markers.

During rugby game, or intensive rugby training there are many high intensity explosive exercises and eccentric muscle contractions, therefore adequate recovery is very important to rugby players. In the present study we have tested the effects of cold water immersion (CWI) after game-simulated (80 min.) rugby training on muscle power recovery and blood markers of muscle damage. Twenty well-trained collegiate male rugby players (age: 20.3 ± 0.6 years old, body height: 1.74 ± 0.05 m, body weight: 85.4 ± 2.0 kg, body fat: 18.2 ± 1.4 %) volunteered for this study. This study was conducted as a cross-over design; i.e., the subjects were randomly assigned either to CWI (n = 10) or passive rest condition (n = 10) for the 1(st) trial and 1 week later the subjects were switched conditions for the 2(nd) trial. After the simulated rugby training, including tackles and body contacts, muscle functional ability and blood markers of muscle damage were tested immediately, after CWI or passive rest, and again 24 hours later. Statistical analysis of all muscle functional tests (10 m dash, counter movement jump, reaction time, side steps) except for 10 seconds maximal pedaling power and blood makers of muscle damage (aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and creatinine) revealed significant main effects for time (p < 0.05). However, no statistically significant interactions were found in any of the muscle functional tests and blood markers between groups and time courses. Our results suggest that a rugby game induces muscle damage and reduces muscle function. However, CWI has no significant restorative effect after an 80-minute rugby game in terms of muscle damage. Key PointsCold water immersion study for the recovery of rugby playersMuscle strength and muscle power were mainly evaluated as well as muscle enzymes of muscle break downSubjects were highly trained rugby players with control group.

Hemispheric Lateralization in Older Adults Who Habitually Play Darts: A Cross-Sectional Study Using Functional Near-Infrared Spectroscopy.

Exercise training integrating physical and cognitive activities is gaining attention because of its potential benefits for brain health. This study focuses on exercise training using a dart game called Wellness Darts. Wellness Darts is a sport involving throwing darts and walking to pull them out of the board, memorizing the score, and subtracting this from the total score, thus requiring the simultaneous performance of two tasks: exercise and calculation. This is expected to maintain and improve cognitive function, and whether this continual darts training affects brain function is of great interest. Before conducting the longitudinal study revealing its effect on brain function, we aimed to cross-sectionally confirm the difference in hemispheric lateralization between expert and non-expert players. Functional near-infrared spectroscopy (fNIRS) was used to measure brain activity for three groups: an expert older group who practiced darts continually, a non-expert older control group, and a non-expert younger control group. Their brain activity patterns were quantified by the lateralization index (LI) and compared between groups. The results showed that the younger and the expert older groups had significantly higher LI values than the non-expert older group, and there was no difference between the expert older and the younger groups. Our results suggest that the Wellness Darts game possibly promotes hemispheric lateralization.

Hand Selection in Dribbling Phases: An Analysis of Non-Dominant Hand Usage and Dribble Change in Basketball.

This study investigates the influence of different dribbling phases on hand selection among basketball players across various categories. A total of 33 guard players, including 11 from high school, college, and NBA teams each, were observed. Video data analysis was utilized to determine the frequency of players using their dominant hands (DHs) and non-dominant hands (NDHs) during in-game dribbling phases. The dribbling phases were classified into three categories: First (the initiation of the dribble), Middle (during the dribble but not in First and Last), and Last (the completion of the dribble). Percentage, means, and standard deviations were computed for each category within the First, Middle, and Last measurements. A two-factor analysis of variance (ANOVA) was conducted, considering player category and dribbling phase as factors. The ANOVA revealed significant main effects of player category (p < 0.01) and dribbling phase (p < 0.01). Post hoc multiple comparisons using Holm's method indicated that, in the First phase, players exhibited a 6.5% higher preference for using their NDHs (43.4 ± 11.9%) compared to the Middle phase (36.9 ± 13.9%) (p < 0.05). Similarly, in the Last phase, players displayed a 5.3% greater inclination towards using their NDHs (42.2 ± 11.7%) compared to the Middle phase (p < 0.05). These findings provide quantitative evidence that the specific dribbling phase influences hand selection during gameplay. The implications of these results are significant for basketball coaches, as they can design targeted training programs and drills that simulate game scenarios and encourage NDH usage. By understanding the factors influencing hand choice, players can enhance their versatility and adaptability on the court. Furthermore, these findings contribute to player performance, skill development, and strategic decision making in dribbling phases.

Physical Fitness Tests as Predictors of High-Intensity Running Performance in Rugby.

Understanding the physical fitness elements that influence high-intensity running ability during rugby matches is crucial for optimizing player performance and developing effective training strategies. In this study, we aimed to investigate the relationships between various physical fitness components and high-intensity running ability in rugby. For this purpose, 60 Japanese university rugby players were randomized into four groups and two matches were played. The participants were monitored in two matches, and their running abilities were assessed using GPS sensors. The running time was divided into three running velocity categories: distance run at ≤5.4 km/h (low-intensity running); distance run at 5.5~17.9 km/h (medium-intensity running), and distance run at ≥18.0 km/h ≤(high-intensity running) and backs and forwards were evaluated separately. To determine which physical fitness test is more predictive of performance, we decided to correlate several physical test performances with the running time intensities during the matches. Independently of the position, the high-intensity running time correlated with the repeated sprint ability (RSA) and the 40 m sprint speed. The results suggest that RSA measured in the field is the most important high-intensity running ability predictor during a match for both positions.

The Stroop effect involves an excitatory-inhibitory fronto-cerebellar loop.

The Stroop effect is a classical, well-known behavioral phenomenon in humans that refers to robust interference between language and color information. It remains unclear, however, when the interference occurs and how it is resolved in the brain. Here we show that the Stroop effect occurs during perception of color-word stimuli and involves a cross-hemispheric, excitatory-inhibitory loop functionally connecting the lateral prefrontal cortex and cerebellum. Participants performed a Stroop task and a non-verbal control task (which we term the Swimmy task), and made a response vocally or manually. The Stroop effect involved the lateral prefrontal cortex in the left hemisphere and the cerebellum in the right hemisphere, independently of the response type; such lateralization was absent during the Swimmy task, however. Moreover, the prefrontal cortex amplified cerebellar activity, whereas the cerebellum suppressed prefrontal activity. This fronto-cerebellar loop may implement language and cognitive systems that enable goal-directed behavior during perceptual conflicts.

Neurophysiological dynamics for psychological resilience: A view from the temporal axis.

When an individual is faced with adversity, the brain and body work cooperatively to adapt to it. This adaptive process is termed psychological resilience, and recent studies have identified several neurophysiological factors ("neurophysiological resilience"), such as monoamines, oscillatory brain activity, hemodynamics, autonomic activity, stress hormones, and immune systems. Each factor is activated in an interactive manner during specific time windows after exposure to stress. Thus, the differences in psychological resilience levels among individuals can be characterized by differences in the temporal dynamics of neurophysiological resilience. In this review, after briefly introducing the frequently used approaches in this research field and the well-known factors of neurophysiological resilience, we summarize the temporal dynamics of neurophysiological resilience. This viewpoint clarifies an important time window, the more-than-one-hour scale, but the neurophysiological dynamics during this window remain elusive. To address this issue, we propose exploring brain-wide oscillatory activities using concurrent functional magnetic resonance imaging (fMRI) and electroencephalogram (EEG) techniques.

In vivo visualization of single-unit recording sites using MRI-detectable elgiloy deposit marking.

Precise localization of single-neuron activity has elucidated functional architectures of the primate cerebral cortex, related to vertically stacked layers and horizontally aligned columns. The traditional "gold standard" method for localizing recorded neuron is histological examination of electrolytic lesion marks at recording sites. Although this method can localize recorded neurons with fine neuroanatomy, the necessity for postmortem analysis prohibits its use in long-term chronic experiments. To localize recorded single-neuron positions in vivo, we introduced MRI-detectable elgiloy deposit marks, which can be created by electrolysis of an elgiloy microelectrode tip and visualized on highly contrasted magnetic resonance (MR) images. Histological analysis validated that the deposit mark centers could be localized relative to neuroanatomy in vivo with single-voxel accuracy, at an in-plane resolution of 200 µm. To demonstrate practical applications of the technique, we recorded single-neuron activity from a monkey performing a cognitive task and localized it in vivo using deposit marks (deposition: 2 µA for 3 min; scanning: fast-spin-echo sequence with 0.15 × 0.15 × 0.8 mm(3) resolution, 120/4,500 ms of echo-time/repetition-time and 8 echo-train-length), as is usually performed with conventional postmortem methods using electrolytic lesion marks. Two localization procedures were demonstrated: 1) deposit marks within a microelectrode track were used to reconstruct a dozen recorded neuron positions along the track directly on MR images; 2) combination with X-ray imaging allowed estimation of hundreds of neuron positions on MR images. This new in vivo method is feasible for chronic experiments with nonhuman primates, enabling analysis of the functional architecture of the cerebral cortex underlying cognitive processes.

Corrigendum: Lactate Metabolism and Satellite Cell Fate.

[This corrects the article DOI: 10.3389/fphys.2020.610983.].