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Japanese English learners have difficulty speaking Double Object (DO; give B A) than Prepositional Object (PO; give A to B) structures which neural underpinning is unknown. In speaking, syntactic and phonological processing follow semantic encoding, conversion of non-verbal mental representation into a structure suitable for expression. To test whether DO difficulty lies in linguistic or prelinguistic process, we conducted functional magnetic resonance imaging. Thirty participants described cartoons using DO or PO, or simply named them. Greater reaction times and error rates indicated DO difficulty. DO compared with PO showed parieto-frontal activation including left inferior frontal gyrus, reflecting linguistic process. Psychological priming in PO produced immediately after DO and vice versa compared to after control, indicated shared process between PO and DO. Cross-structural neural repetition suppression was observed in occipito-parietal regions, overlapping the linguistic system in pre-SMA. Thus DO and PO share prelinguistic process, whereas linguistic process imposes overload in DO.

A systematic study of the oxidation of 3-hydroxy-2-substituted isoindolin-1-ones (hydroxylactams) and their conversion to the corresponding phthalimides was undertaken using three oxidants. Of special interest was the introduction of nickel peroxide (NiO2) as an oxidation system for hydroxylactams and comparison of its performance with the commonly used pyridinium chlorochromate (PCC) and iodoxybenzoic acid (IBX) reagents. Using a range of hydroxylactams, optimal conversions of these substrates to the corresponding imides was achieved with 50 equivalents of freshly prepared NiO2 in refluxing toluene over 5–32 h reaction times. By comparison, oxidations of the same substrates using PCC/silica gel (three equivalents) and IBX (three equivalents) required oxidation times of 1–3 h for full conversion but required lengthier purification. While nominal amounts (~25 mg) of substrate hydroxylactams were used to ascertain conversion, scale-up procedures using all three methods gave good to excellent isolated yields of imides.

Background Cognitive models indicated that social anxiety disorder (SAD) would be caused and maintained by a biased attentional processing of threatening information. This study investigates whether socially anxious children may present impaired attentional engagement and disengagement from negative emotional faces, as well as their underlying event-related potential responses. Methods and findings Fifteen children with high levels of social anxiety (HSA; 9 boys; mean age = 9.99y; SD = 1.14) and twenty low socially anxious children (LSA; 16 boys; mean age = 10.47y; SD = 1.17) participated in a spatial cueing task in which they had to detect targets following neutral/disgusted faces in a valid or invalid location. No group effect was reported on reaction times [p>.05]. However, electrophysiological data showed lower P3a amplitude in HSA children compared with the LSA group when processing facial stimuli. They also reported larger N2 amplitudes for valid-disgusted targets and a larger P3a amplitude for the invalid-disgusted ones. Conclusion In terms of electrophysiological data, our results validated, the hypothesis of attentional disengagement difficulties in SAD children. We also confirm the idea that high levels of social anxiety are associated with cognitive control impairments and have a greater impact on the processing efficiency than on the performance effectiveness.

Humans are emotionally affected by cute or infantile appearances, typical of baby animals and humans, which in turn often leads to careful and cautious behavior. The purpose of this pre-registered study was to examine whether looking at cute images of baby pets improves performance of computerized cognitive-motor tasks. Ninety-eight participants were recruited for this online study and were randomly assigned to two experimental groups. The participants in one group performed two cognitive-motor tasks (Simon task and alternate task-switching task) before and after viewing images of adult pets and the participants in the other group performed the tasks before and after viewing images of baby pets. The participants who viewed images of baby pets rated them as significantly cuter (Cohen’s d = 0.50) and more infantile (Cohen’s d = 1.56) compared with those who viewed images of adult pets. All participants improved their performance from the pre-test to the post-test, but no differences in correct responses and reaction times were seen between the groups. However, pet ownership appeared to serve as a moderating variable with pet owners performing the Simon task faster than non-pet owners. In addition, pet owners reacted faster in the alternate task-switching task after viewing cute and infantile images but not after viewing images of adult pets. This effect was not found among non-pet owners. In conclusion, this study did not find that viewing cute images improves cognitive-motor performance, yet this may be dependent on moderators like pet ownership.

Stop-signal tasks (SSTs) combined with human electro-cortical recordings (Event-Related Potentials, ERPs) have revealed mechanisms associated with successful stopping (relative to failed), presumably contributing to inhibitory control. The corresponding ERP signatures have been labeled stop N1 (+/- 100-ms latency), stop N2 (200 ms), and stop P3 (160-250 ms), and argued to reflect more proactive (N1) versus more reactive (N2, P3) mechanisms. However, stop N1 and stop N2, as well as latencies of stop-P3, appear to be quite inconsistent across studies. The present work addressed the possible influence of stop-signal salience, expecting high salience to induce clear stop N1s but reduced stop N2s, and short-latency stop P3s. Three SST varieties were combined with high-resolution EEG. An imperative visual (go) stimulus was occasionally followed by a subsequent (stop) stimulus that signalled to withhold the just initiated response. Stop-Signal Reaction Times (SSRTs) decreased linearly from visual-low to visual-high-salience to auditory. Auditory Stop N1 was replicated. A C1-like visual evoked potential (latency < 100 ms) was observed only with high salience, but not robustly associated with successful versus failed stops. Using the successful-failed contrast a visual stop-N1 analogue (112-156 ms post-stop-signal) was identified, as was right-frontal stop N2, but neither was sensitive to salience. Stop P3 had shorter latency for high than for low salience, and the extent of the early high-salience stop P3 correlated inversely with SSRT. These results suggest that salience-enhanced inhibitory control as manifest in SSRTs is associated with reactive rather than proactive electrocortical mechanisms.

Despite the progress in the development of automated vehicles in the last decade, reaching the level of reliability required at large-scale deployment at an economical price and combined with safety requirements is still a long road ahead. In certain use cases, such as automated shuttles and taxis, where there is no longer even a steering wheel and pedals required, remote driving could be implemented to bridge this gap; a remote operator can take control of the vehicle in situations where it is too difficult for an automated system to determine the next actions. In logistics, it could even be implemented to solve already more pressing issues such as shortage of truck drivers, by providing more flexible working conditions and less standstill time of the truck. An important aspect of remote driving is the connection between the remote station and the vehicle. With the current roll-out of 5G mobile technology in many countries throughout the world, the implementation of remote driving comes closer to large-scale deployment. 5G could be a potential game-changer in the deployment of this technology. In this work, we examine the remote driving application and network-level performance of remote driving on a recently deployed sub-6-GHz commercial 5G stand-alone (SA) mobile network. It evaluates the influence of the 5G architecture, such as mobile edge computing (MEC) integration, local breakout, and latency on the application performance of remote driving. We describe the design, development (based on Hardware-in-the-Loop simulations), and performance evaluation of a remote driving solution, tested on both 5G and 4G mobile SA networks using two different vehicles and two different remote stations. Two test cases have been defined to evaluate the application and network performance and are evaluated based on position accuracy, relative reaction times, and distance perception. Results show the performance of the network to be sufficient for remote driving applications at relatively low speeds (&lt;40 km/h). Network latencies compared with 4G have dropped to half. A strong correlation between latency and remote driving performance is not clearly seen and requires further evaluation taking into account the influence of the user interface.

Researchers have recently begun to question the specificity and reliability of conflict adaptation effects, also known as sequential congruency effects (SCEs), a highly cited effect in cognitive psychology. Some have even used the lack of reliability across tasks (e.g., Flanker, and Stroop) to argue against models of cognitive control that have dominated the field for decades. The present study tested the possibility that domain-general processes across tasks might appear on more sensitive mouse-tracking metrics rather than overall reaction times. The relationship between SCE effects on the Stroop and Flanker tasks were examined for the first time using a mouse-tracking paradigm. Three main findings emerged: (1) Robust SCEs were observed for both the Stroop and Flanker tasks at the group level, (2) Within-task split-half reliabilities for the SCE across dependent variables were weak at best and non-existent in many cases, and (3) SCEs for the Flanker and Stroop tasks did not correlate with each other for overall reaction times, but did show significant correlations between tasks on more dynamic measures that captured processes before response execution. These findings contribute to the literature by highlighting how mouse-tracking may be a fruitful avenue by which future studies can examine the specificity and reliability of conflict adaptation and tease apart different theoretical models producing the effects.

The relationship between the age of acquisition (AoA) of words and their cerebral hemispheric representation is controversial because the experimental results have been contradictory. However, most of the lexical processing experiments were performed with stimuli consisting of written words. If we want to compare the processing of words learned very early in infancy—when children cannot read—with words learned later, it seems more logical to employ spoken words as experimental stimuli. This study, based on the auditory lexical decision task, used spoken words that were classified according to an objective criterion of AoA with extremely distant means (2.88 vs. 9.28 years old). As revealed by the reaction times, both early and late words were processed more efficiently in the left hemisphere, with no AoA × Hemisphere interaction. The results are discussed from a theoretical point of view, considering that all the experiments were conducted using adult participants.

AbstractLetter similarity (i.e., perceptual distance) is a critical measure to better understand letter perception and literacy development. Despite its importance, however, measurements of letter similarity for non-alphabetic scripts are limited, and the shortage of letter similarity for non-alphabetic script interferes with the identification of the universality and the uniqueness of letter perception systems across different scripts. In the present study, we provide a comprehensive matrix of letter similarity for Japanese kana letters (hiragana and katakana). We obtained the discrimination reaction times for simultaneously presented letter pairs and calculated the perceptual distance of 4,278 letter pairs by inversing the time. The matrix showed significant correlations with previously obtained letter similarity for hiragana and katakana. An additional experiment showed that letter pairs for the same sounds (え–エ) produced significantly slower responses compared with those for different sounds (え–コ). However, the differences in reaction times between the same and different sound conditions were smaller than the sequentially presented conditions, suggesting that the matrix was partially attributable to knowledge-based factors (e.g., letter-sound knowledge). This first comprehensive matrix of letter similarity (i.e., perceptual distance) for Japanese kana letters (hiragana and katakana) will be useful for researchers interested in letter perception and literacy development.

Abstract Objective Small area electrodes enable preferential activation of nociceptive fibers. It is debated, however, whether co-activation of large fibers still occurs for the existing electrode designs. Moreover, existing electrodes are limited to low stimulation intensities, for which behavioral and physiological responses may be considered less reliable. A recent optimization study showed that there is a potential for improving electrode performance and increase the range of possible stimulation intensities. Based on those results, the present study introduces and tests a novel planar concentric array electrode design for small fiber activation in healthy volunteers. Approach Volunteers received electrical stimulation with the planar concentric array electrode and a regular patch electrode. Perception thresholds were estimated at the beginning and the end of the experiment. Evoked cortical potentials were recorded in blocks of 30 stimuli. For the patch, stimulation intensity was set to two times perception threshold (PT), while three intensities, 2, 5, and 10 times PT, were applied with the planar concentric array electrode. Sensation quality, numerical-rating scores, and reaction times were obtained for each PT estimation and during each block of evoked potential recordings. Main results Stimulation with the patch electrode was characterized as dull, while stimulation with the planar concentric array electrode was characterized as sharp, with increased sharpness for increasing stimulus intensity. Likewise, NRS scores were higher for the planar concentric array electrode compared to the patch and increased with increasing stimulation intensity. Reaction times and ERP latencies were longer for the planar concentric array electrode compared to the patch. Significance The presented novel planar concentric array electrode is a small, non-invasive, and single-use electrode that has the potential to investigate small fiber neuropathy and pain mechanisms, as it is small fiber preferential for a wide range of stimulation intensities.