EEG and fNIRS datasets based on Stroop task during two weeks of high-altitude exposure in new immigrants.

Maintaining sufficient cerebral oxygen metabolism is crucial for human survival, especially in challenging conditions such as high-altitudes. Human cognitive neural activity is sensitive to fluctuations in oxygen levels. However, there is a lack of publicly available datasets on human behavioural responses and cerebral dynamics assessments during the execution of conflicting tasks in natural hypoxic environments. We recruited 80 healthy new immigrant volunteers (males, aged 20 ± 2 years) and employed the Stroop cognitive conflict paradigm. After a two-week exposure to both high and low-altitudes, the behavioural performance, prefrontal oxygen levels, and electroencephalography (EEG) signals were recorded. Comparative analyses were conducted on the behavioural reaction times and accuracy during Stroop tasks, and statistical analyses of participants' prefrontal oxygen levels and EEG signals were performed. We anticipate that our open-access dataset will contribute to the development of monitoring devices and algorithms, designed specifically for measuring cerebral oxygen and EEG dynamics in populations exposed to extreme environments, particularly among individuals suffering from oxygen deficiency.

Video game addiction is associated with early stage of inhibitory control problems: An event-related potential study using cued Go/NoGo task.

Video game addiction (VGA) is associated with cognitive problems, particularly deficits in inhibitory control. The present study aimed to investigate behavioural responses and event-related potential associated with specific response inhibition using the cued Go/NoGo task to examine the effects of VGA on brain activity related to response inhibition. Twenty-five individuals addicted to video games (action video games) and 25 matched healthy controls participated in the study. The results showed that the VGA group had significantly more commission error in the NoGo trials and faster reaction time in the Go trials compared with the control group. The event-related potential analyses revealed significant reductions in amplitudes of N2 cue and N2 NoGo in the VGA group. While there was no significant difference between the N2 amplitudes of the Go and NoGo trials in the VGA group, the control group had a larger N2 amplitude in the NoGo trials. These results indicate that VGA subjects have difficulties in the early stages of response inhibition, as well as some level of impairment in proactive cognitive control.

Smooth pursuit inhibition reveals audiovisual enhancement of fast movement control.

The sudden onset of a visual object or event elicits an inhibition of eye movements at latencies approaching the minimum delay of visuomotor conductance in the brain. Typically, information presented via multiple sensory modalities, such as sound and vision, evokes stronger and more robust responses than unisensory information. Whether and how multisensory information affects ultra-short latency oculomotor inhibition is unknown. In two experiments, we investigate smooth pursuit and saccadic inhibition in response to multisensory distractors. Observers tracked a horizontally moving dot and were interrupted by an unpredictable visual, auditory, or audiovisual distractor. Distractors elicited a transient inhibition of pursuit eye velocity and catch-up saccade rate within ∼100 ms of their onset. Audiovisual distractors evoked stronger oculomotor inhibition than visual- or auditory-only distractors, indicating multisensory response enhancement. Multisensory response enhancement magnitudes were equal to the linear sum of responses to component stimuli. These results demonstrate that multisensory information affects eye movements even at ultra-short latencies, establishing a lower time boundary for multisensory-guided behavior. We conclude that oculomotor circuits must have privileged access to sensory information from multiple modalities, presumably via a fast, subcortical pathway.

High visual salience of alert signals can lead to a counterintuitive increase of reaction times.

It is often assumed that rendering an alert signal more salient yields faster responses to this alert. Yet, there might be a trade-off between attracting attention and distracting from task execution. Here we tested this in four behavioral experiments with eye-tracking using an abstract alert-signal paradigm. Participants performed a visual discrimination task (primary task) while occasional alert signals occurred in the visual periphery accompanied by a congruently lateralized tone. Participants had to respond to the alert before proceeding with the primary task. When visual salience (contrast) or auditory salience (tone intensity) of the alert were increased, participants directed their gaze to the alert more quickly. This confirms that more salient alerts attract attention more efficiently. Increasing auditory salience yielded quicker responses for the alert and primary tasks, apparently confirming faster responses altogether. However, increasing visual salience did not yield similar benefits: instead, it increased the time between fixating the alert and responding, as high-salience alerts interfered with alert-task execution. Such task interference by high-salience alert-signals counteracts their more efficient attentional guidance. The design of alert signals must be adapted to a "sweet spot" that optimizes this stimulus-dependent trade-off between maximally rapid attentional orienting and minimal task interference.

Effects of expectation on face perception and its association with expertise.

Perceptual decisions are derived from the combination of priors and sensorial input. While priors are broadly understood to reflect experience/expertise developed over one's lifetime, the role of perceptual expertise at the individual level has seldom been directly explored. Here, we manipulate probabilistic information associated with a high and low expertise category (faces and cars respectively), while assessing individual level of expertise with each category. 67 participants learned the probabilistic association between a color cue and each target category (face/car) in a behavioural categorization task. Neural activity (EEG) was then recorded in a similar paradigm in the same participants featuring the previously learned contingencies without the explicit task. Behaviourally, perception of the higher expertise category (faces) was modulated by expectation. Specifically, we observed facilitatory and interference effects when targets were correctly or incorrectly expected, which were also associated with independently measured individual levels of face expertise. Multivariate pattern analysis of the EEG signal revealed clear effects of expectation from 100 ms post stimulus, with significant decoding of the neural response to expected vs. not stimuli, when viewing identical images. Latency of peak decoding when participants saw faces was directly associated with individual level facilitation effects in the behavioural task. The current results not only provide time sensitive evidence of expectation effects on early perception but highlight the role of higher-level expertise on forming priors.

Vergence-Accommodation Conflict: Increased Presbyopia in Virtual Reality.

BACKGROUND: Performance and symptoms in completing a visual search task on a PC monitor and using a head-mounted display (HMD) were compared for different viewing conditions and between users of different ages. PATIENTS AND METHODS: Twenty-three young (M = 30 y, SD = 7 y) and 23 older (M = 52 y, SD = 5 y) participants performed a visual search task presented on a PC monitor. The task was repeated using an HMD for a near and a far virtual viewing distance. Reaction times (RT), detection sensitivity (d'), and symptoms were recorded for the three different viewing conditions. RESULTS: RT and d' were not affected by the viewing condition (p > 0.05). In contrast, symptoms significantly depended on the viewing condition but were, in part, not significantly affected by age. It is interesting to note that although not significant, young participants reported more ocular symptoms than older participants in the near vision task carried out using the HMD. DISCUSSION: HMD increases visual symptoms. However, HMD could be, in part, a remedy to problems when using visual aids for near work, in particular for presbyopes.

Sex similarities and dopaminergic differences in interval timing.

Rodent behavioral studies have largely focused on male animals, which has limited the generalizability and conclusions of neuroscience research. Working with humans and rodents, we studied sex effects during interval timing that requires participants to estimate an interval of several seconds by making motor responses. Interval timing requires attention to the passage of time and working memory for temporal rules. We found no differences between human females and males in interval timing response times (timing accuracy) or the coefficient of variance of response times (timing precision). Consistent with prior work, we also found no differences between female and male rodents in timing accuracy or precision. In female rodents, there was no difference in interval timing between estrus and diestrus cycle stages. Because dopamine powerfully affects interval timing, we also examined sex differences with drugs targeting dopaminergic receptors. In both female and male rodents, interval timing was delayed after administration of sulpiride (D2-receptor antagonist), quinpirole (D2-receptor agonist), and SCH-23390 (D1-receptor antagonist). By contrast, after administration of SKF-81297 (D1-receptor agonist), interval timing shifted earlier only in male rodents. These data illuminate sex similarities and differences in interval timing. Our results have relevance for rodent models of both cognitive function and brain disease by increasing representation in behavioral neuroscience. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Task demand mediates the interaction of spatial and temporal attention.

Psychophysical studies typically test attentional mechanisms in isolation, but in everyday life they interact to optimize human behavior. We investigated whether spatial and temporal attention interact in two orientation discrimination experiments that vary in task demand. We manipulated temporal and spatial attention separately and conjointly with well-established methods for testing each spatial or temporal attention. We assessed sensitivity (d') and reaction time for every combination of spatial and timing cues, each of which was valid, neutral, or invalid. Spatial attention modulated sensitivity (d') and speed (reaction time) across temporal attention conditions. Temporal attention modulated sensitivity and speed under high- but not low- task demands. Furthermore, spatial and temporal attention interacted for the high-demand task. This study reveals that task demand matters; in a simple task spatial attention suffices to improve performance, whereas in a more demanding task both spatial and temporal attention interact to boost performance, albeit in a subadditive fashion.

Real-time cortical dynamics during motor inhibition.

The inhibition of action is a fundamental executive mechanism of human behaviour that involve a complex neural network. In spite of the progresses made so far, many questions regarding the brain dynamics occurring during action inhibition are still unsolved. Here, we used a novel approach optimized to investigate real-time effective brain dynamics, which combines transcranial magnetic stimulation (TMS) with simultaneous electroencephalographic (EEG) recordings. 22 healthy volunteers performed a motor Go/NoGo task during TMS of the hand-hotspot of the primary motor cortex (M1) and whole-scalp EEG recordings. We reconstructed source-based real-time spatiotemporal dynamics of cortical activity and cortico-cortical connectivity throughout the task. Our results showed a task-dependent bi-directional change in theta/gamma supplementary motor cortex (SMA) and M1 connectivity that, when participants were instructed to inhibit their response, resulted in an increase of a specific TMS-evoked EEG potential (N100), likely due to a GABA-mediated inhibition. Interestingly, these changes were linearly related to reaction times, when participants were asked to produce a motor response. In addition, TMS perturbation revealed a task-dependent long-lasting modulation of SMA-M1 natural frequencies, i.e. alpha/beta activity. Some of these results are shared by animal models and shed new light on the physiological mechanisms of motor inhibition in humans.

HD-tDCS mitigates the executive vigilance decrement only under high cognitive demands.

Maintaining vigilance is essential for many everyday tasks, but over time, our ability to sustain it inevitably decreases, potentially entailing severe consequences. High-definition transcranial direct current stimulation (HD-tDCS) has proven to be useful for studying and improving vigilance. This study explores if/how cognitive load affects the mitigatory effects of HD-tDCS on the vigilance decrement. Participants (N = 120) completed a modified ANTI-Vea task (single or dual load) while receiving either sham or anodal HD-tDCS over the right posterior parietal cortex (rPPC). This data was compared with data from prior studies (N = 120), where participants completed the standard ANTI-Vea task (triple load task), combined with the same HD-tDCS protocol. Against our hypotheses, both the single and dual load conditions showed a significant executive vigilance (EV) decrement, which was not affected by the application of rPPC HD-tDCS. On the contrary, the most cognitively demanding task (triple task) showed the greatest EV decrement; importantly, it was also with the triple task that a significant mitigatory effect of the HD-tDCS intervention was observed. The present study contributes to a more nuanced understanding of the specific effects of HD-tDCS on the vigilance decrement considering cognitive demands. This can ultimately contribute to reconciling heterogeneous effects observed in past research and fine-tuning its future clinical application.

A fully spiking coupled model of a deep neural network and a recurrent attractor explains dynamics of decision making in an object recognition task.

Objective.Object recognition and making a choice regarding the recognized object is pivotal for most animals. This process in the brain contains information representation and decision making steps which both take different amount of times for different objects. While dynamics of object recognition and decision making are usually ignored in object recognition models, here we proposed a fully spiking hierarchical model, explaining the process of object recognition from information representation to making decision.Approach.Coupling a deep neural network and a recurrent attractor based decision making model beside using spike time dependent plasticity learning rules in several convolutional and pooling layers, we proposed a model which can resemble brain behaviors during an object recognition task. We also measured human choices and reaction times in a psychophysical object recognition task and used it as a reference to evaluate the model.Main results.The proposed model explains not only the probability of making a correct decision but also the time that it takes to make a decision. Importantly, neural firing rates in both feature representation and decision making levels mimic the observed patterns in animal studies (number of spikes (p-value < 10-173) and the time of the peak response (p-value < 10-31) are significantly modulated with the strength of the stimulus). Moreover, the speed-accuracy trade-off as a well-known characteristic of decision making process in the brain is also observed in the model (changing the decision bound significantly affect the reaction time (p-value < 10-59) and accuracy (p-value < 10-165)).Significance.We proposed a fully spiking deep neural network which can explain dynamics of making decision about an object in both neural and behavioral level. Results showed that there is a strong and significant correlation (r= 0.57) between the reaction time of the model and of human participants in the psychophysical object recognition task.

Exploring the influence of a 4-week aerobic exercise intervention on cognitive control processes in young adults: An SFT and DDM study.

Prior research has highlighted the potential impact of aerobic exercise on cognitive functioning, particularly in situations demanding heightened cognitive control. However, the mechanism underlying this cognitive enhancement has remained unknown. To address this issue, this study examined the impact of a 4-week aerobic exercise program on cognitive control processes in young male adults (aerobic exercise group: n=36, aged 21.42±1.13years) in comparison to a control group that received no treatment (n=33, aged 21.82±1.76years). We employed the redundant-target Stroop task to investigate inhibition processes at both perceptual and semantic stages. Utilizing systems factorial technology and the drift diffusion model, we assessed changes in resilience capacity and the underlying cognitive mechanisms. Our primary findings revealed a significant reduction in mean response times (RTs) in the aerobic exercise group, accompanied by a decrease in RT variability when inhibiting semantic processing. Resilience capacity significantly declined in both groups at similar levels. Notably, the aerobic exercise group exhibited an enhanced drift rate during automatic response inhibition and reduced non-decision time in the condition involving the inhibition of perceptual information. This study deepens our understanding of how a 4-week aerobic exercise program enhances cognitive control, affecting distinct cognitive processes, including processing speed, information accumulation during automatic response inhibition, and sensory and motor processes in perceptual conflicts. Our research underscores the potential of aerobic exercise as a means to boost cognitive control among young adults.

Perceptual decoupling or trigger happiness: the effect of response delays and shorter presentation times on a go-no-go task with a high go prevalence.

In the current investigation, we modified the high Go, low No-Go Sustained Attention to Response Task (SART). Some researchers argue a commission error, an inappropriate response to a No-Go stimulus, in the SART is due to the participant being inattentive, or perceptually decoupled, during stimulus onset. Response delays in the SART reduce commission errors. A response delay may therefore enable a participant who is initially inattentive to recouple their attention in time to appropriately perceive the stimulus and withhold a response to a No-Go stimulus. However, shortening stimulus display duration in the SART should limit the possibility of the participant identifying the stimulus later, if they are initially not attending the stimulus. A response delay should not reduce commission errors if stimulus duration is kept to the minimum duration enabling stimulus recognition. In two experiments, we shortened stimulus onset to offset duration and added response delays of varying lengths. In both experiments, even when stimulus duration was shortened, response delays notably reduced commission errors if the delay was greater than 250 ms. In addition, using the Signal Detection Theory perspective in which errors of commission in the SART are due to a lenient response bias-trigger happiness, we predicted that response delays would result in a shift to a more conservative response bias in both experiments. These predictions were verified. The errors of commission in the SART may not be a measures of conscious awareness per se, but instead indicative of the level of participant trigger happiness-a lenient response bias.

Effects of finger pinch motor imagery on short-latency afferent inhibition and corticospinal excitability.

Motor imagery is a cognitive process involving the simulation of motor actions without actual movements. Despite the reported positive effects of motor imagery training on motor function, the underlying neurophysiological mechanisms have yet to be fully elucidated. Therefore, the purpose of the present study was to investigate how sustained tonic finger-pinching motor imagery modulates sensorimotor integration and corticospinal excitability using short-latency afferent inhibition (SAI) and single-pulse transcranial magnetic stimulation (TMS) assessments, respectively. Able-bodied individuals participated in the study and assessments were conducted under two experimental conditions in a randomized order between participants: (1) participants performed motor imagery of a pinch task while observing a visual image displayed on a monitor (Motor Imagery), and (2) participants remained at rest with their eyes fixed on the monitor displaying a cross mark (Control). For each condition, sensorimotor integration and corticospinal excitability were evaluated during sustained tonic motor imagery in separate sessions. Sensorimotor integration was assessed by SAI responses, representing inhibition of motor-evoked potentials (MEPs) in the first dorsal interosseous muscle elicited by TMS following median nerve stimulation. Corticospinal excitability was assessed by MEP responses elicited by single-pulse TMS. There was no significant difference in the magnitude of SAI responses between motor imagery and Control conditions, while MEP responses were significantly facilitated during the Motor Imagery condition compared to the Control condition. These findings suggest that motor imagery facilitates corticospinal excitability, without altering sensorimotor integration, possibly due to insufficient activation of the somatosensory circuits or lack of afferent feedback during sustained tonic motor imagery.

Investigating the Effect of Contextual Cueing with Face Stimuli on Electrophysiological Measures in Younger and Older Adults.

Extracting repeated patterns from our surroundings plays a crucial role in contextualizing information, making predictions, and guiding our behavior implicitly. Previous research showed that contextual cueing enhances visual search performance in younger adults. In this study, we investigated whether contextual cueing could also improve older adults' performance and whether age-related differences in the neural processes underlying implicit contextual learning could be detected. Twenty-four younger and 25 older participants performed a visual search task with contextual cueing. Contextual information was generated using repeated face configurations alongside random new configurations. We measured RT difference between new and repeated configurations; ERPs to uncover the neural processes underlying contextual cueing for early (N2pc), intermediate (P3b), and late (r-LRP) processes; and multiscale entropy and spectral power density analyses to examine neural dynamics. Both younger and older adults showed similar contextual cueing benefits in their visual search efficiency at the behavioral level. In addition, they showed similar patterns regarding contextual information processing: Repeated face configurations evoked decreased finer timescale entropy (1-20 msec) and higher frequency band power (13-30 Hz) compared with new configurations. However, we detected age-related differences in ERPs: Younger, but not older adults, had larger N2pc and P3b components for repeated compared with new configurations. These results suggest that contextual cueing remains intact with aging. Although attention- and target-evaluation-related ERPs differed between the age groups, the neural dynamics of contextual learning were preserved with aging, as both age groups increasingly utilized more globally grouped representations for repeated face configurations during the learning process.

Action initiation and action inhibition follow the same time course when compared under matched experimental conditions.

The ability to initiate an action quickly when needed and the ability to cancel an impending action are both fundamental to action control. It is often presumed that they are qualitatively distinct processes, yet they have largely been studied in isolation and little is known about how they relate to one another. Comparing previous experimental results shows a similar time course for response initiation and response inhibition. However, the exact time course varies widely depending on experimental conditions, including the frequency of different trial types and the urgency to respond. For example, in the stop-signal task, where both action initiation and action inhibition are involved and could be compared, action inhibition is typically found to be much faster. However, this apparent difference is likely due to there being much greater urgency to inhibit an action than to initiate one in order to avoid failing at the task. This asymmetry in the urgency between action initiation and action inhibition makes it impossible to compare their relative time courses in a single task. Here, we demonstrate that when action initiation and action inhibition are measured separately under conditions that are matched as closely as possible, their speeds are not distinguishable and are positively correlated across participants. Our results raise the possibility that action initiation and action inhibition may not necessarily be qualitatively distinct processes but may instead reflect complementary outcomes of a single decision process determining whether or not to act.NEW & NOTEWORTHY The time courses of initiating an action and canceling an action have largely been studied in isolation, and little is known about their relationship. Here, we show that when measured under comparable conditions the speeds of action initiation and action inhibition are the same. This finding raises the possibility that these two functions may be more closely related than previously assumed, with potentially important implications for their underlying neural basis.

Bayesian interpretation of the prefrontal P2 ERP component based on stimulus/response mapping uncertainty.

The brain can be seen as a predictive system continuously computing prior information to guess posterior probabilities minimizing sources of uncertainty. To test this Bayesian view of the brain, event-related potentials (ERP) methods have been used focusing on the well-known P3 component, traditionally associated with decision-making processes and sources of uncertainty regarding target probability. Another ERP component linked with decision-making is the prefrontal P2 (pP2) component, which has never been considered within the Bayesian framework. To test which source of uncertainty could be associated with the pP2, uncertainty induced by target probability and stimulus-response (S/R) mapping were modulated in three visuomotor tasks. Results showed that the pP2 had the largest amplitude in the task with the largest uncertainty regarding the S/R mapping and degraded as the S/R mapping became more predictable. The P3 was maximal in the tasks with larger uncertainty regarding the target probability. While we confirmed the P3 association with target probability, we extended our knowledge on the pP2 associating it with S/R mapping uncertainty. This component, which has been previously localized within the anterior insular cortex, may minimize S/R mapping uncertainty allowing response-related evidence accumulation and comparing current events with internal representations to extract action-related probabilities.

Why is there an error negativity on correct trials? A reappraisal.

In healthy subjects, the Error Negativity (Ne) was initially reported on errors and on partial errors, only. Later on, application of the Laplacian transformation to EEG data unmasked a Ne-like wave (Nc) that shares a main generator with the Ne, suggesting that the Nc is just a small Ne. However, the reason why a small Ne would persist on correct responses remains unclear. Now, sometimes, subthreshold EMG activations in the muscles corresponding to correct responses (not strong enough to reach the response threshold) can precede full-blown correct responses. These "partially correct" activities seem to correspond to (force) execution errors, as they evoke a sizeable Ne. Within the frames of the Reward Value and Prediction Model or of the Predicted Response-Outcome model we propose that the action monitoring system evokes a Ne/Nc on correct responses because, even when a correct choice has been made, the accuracy of response (force) execution cannot be fully predicted. If this interpretation is correct, it can be assumed that, once these execution errors have been corrected, the correctness of the (full-blown) correcting response is highly predictable. Consequently, they should evoke a smaller Nc/Ne than "pure" correct responses. We show, that for the response thresholds set in the present experiment, the correcting response of the trials containing a partially correct activation evoke no identifiable Nc at all. Therefore it seems that there usually is an Error Negativity on correct trials because the correctness of response (force) execution cannot be fully predicted.

Effects of anxiety state on N400 event-related brain potential response to unexpected semantic stimuli.

Emotional states can influence how people use meaningful context to make predictions about what comes next. To measure whether state anxiety influences such prediction, we used the N400 event-related brain potential (ERP) response to semantic stimuli, whose amplitude is smaller (less negative) when the stimulus is more predicted based on preceding context. Participants (n = 28) were randomized to one of two groups, who underwent either an "anxious-uncertainty" procedure previously shown to increase anxiety, or a control procedure. Both before and after this procedure, participants' ERPs were recorded while they viewed category definitions (e.g., "a type of fruit"), each followed by a target word that was either a high-typicality category exemplar ("apple"), low-typicality exemplar ("cherry"), or non-exemplar ("clamp") of the category. Participants' task was to respond by pressing one of two buttons to indicate whether the target represented a member of the category. As expected, based on previous work, overall, N400 amplitudes were largest (most negative) in response to non-exemplars, intermediate to low-typicality exemplars, and smallest to high-typicality exemplars. N400 amplitudes were larger to non-exemplars after the anxious-uncertainty procedure than after the control procedure. N400 amplitudes to both types of exemplars did not differ after the anxious-uncertainty procedure versus the control procedure. The results are consistent with participants devoting more neural resources to processing contextually unexpected items under anxious states, rather than anxiety facilitating processing of expected items.

On the impact of on-road partially-automated driving on drivers' cognitive workload and attention allocation.

The use of partially-automated or SAE level-2 vehicles is expected to change the role of the human driver from operator to supervisor, which may have an effect on the driver's workload and visual attention. In this study, 30 Ontario drivers operated a vehicle in manual and partially-automated mode. Cognitive workload was measured by means of the Detection Response Task, and visual attention was measured by means of coding glances on and off the forward roadway. No difference in cognitive workload was found between driving modes. However, drivers spent less time glancing at the forward roadway, and more time glancing at the vehicle's touchscreen. These data add to our knowledge of how vehicle automation affects cognitive workload and attention allocation, and show potential safety risks associated with the adoption of partially-automated driving.