Blocks Of Task Research Articles

Amygdala and nucleus accumbens activation during reward anticipation moderates the association between life stressor frequency and depressive symptoms

BackgroundLife stressors confer risk for depressive symptoms, but individuals vary in the extent of their sensitivity to life stressors. One protective factor may be an individual's level of reward sensitivity, e.g., a stronger neurobiological response to environmental rewards may mitigate emotional responses to stressors. However, the nature of neurobiological reward sensitivity that corresponds with stress resilience is unknown. Further, this model is untested in adolescence, when life stressor frequency and depression increase. MethodsWe tested the hypothesis that stronger reward-related activation in the left and right nucleus accumbens (NAc), amygdala, and medial prefrontal cortex (mPFC) attenuates the strength of the stress-depression relation. We measured BOLD activation throughout Win and Lose blocks of a monetary reward task, as well as during anticipation and outcome phases of the task. Participants (N = 151, ages 13–19) were recruited to be stratified on risk for mood disorders to enhance variance in depressive symptoms. ResultsActivation during anticipation of rewards in the bilateral amygdala and NAc, but not mPFC, buffered the association between life stressors and depressive symptoms. This buffering effect was not found for reward outcome activation or activation across Win blocks. ConclusionsResults highlight the importance of reward anticipation activation of subcortical structures in attenuating the stress-depression link, suggesting that reward motivation may be a cognitive mechanism through which this stress buffering occurs.

Behavioral and electrophysiological evidence for the flexible recruitment of feature- and object-based processing in visual working memory comparison

Previous research is inconclusive on when visual working memory (VWM) can be object-based or feature-based. Prior event-related potential (ERP) studies using change detection tasks have found that amplitudes of the N200—an ERP index of VWM comparison— are sensitive to changes in both relevant and irrelevant features, suggesting a bias toward object-based processing. To test whether VWM comparison processing can operate in a feature-based manner, we aimed to create circumstances that would support feature-based processing by: 1) using a strong task-relevance manipulation, and 2) repeating features within a display. Participants completed two blocks of a change detection task for four-item displays in which they were told to respond to color changes (task relevant) but not shape changes (task irrelevant). The first block contained only task-relevant changes to create a strong task-relevance manipulation. In the second block, both relevant and irrelevant changes were present. In both blocks, half of the arrays contained within-display feature repetitions (e.g. two items of the same color or shape). We found that during the second block, N200 amplitudes were sensitive to task-relevant but not irrelevant features regardless of repetition status, consistent with feature-based processing. However, analyses of behavioral data and N200 latencies suggested that object-based processing was occurring at some stages of VWM processing on task-irrelevant feature change trials. In particular, task-irrelevant changes may be processed after no task-relevant feature change is revealed. Overall, the results from the current study suggest that the VWM processing is flexible and can be either object- or feature-based.

Little fast, little slow, should I stay or should I go? Adapting cognitive control to local-global temporal prediction across typical development.

Adaptive cognitive control (CC), the ability to adjust goal-directed behavior according to changing environmental demand, can be instantiated bottom-up by implicit knowledge, including temporal predictability of task-relevant events. In S1-S2 tasks, either local (trial-by-trial hazard expectation) or global (block-by-block expectation) temporal information can induce prediction, allowing for proactive action control. Recent developmental evidence showed that adaptive CC based on global temporal prediction emerges earlier than when it is based on the local one only. However, very little is known about how children learn to dynamically adjust behavior on the fly according to changing global predictive information. Addressing this issue is nevertheless crucial to unravel the mechanisms underlying adaptive CC flexibility. Here we used a modified version of the Dynamic Temporal Prediction task to investigate how typically developing younger (6-8 years) and older children (9-11 years), adolescents (12-15 years) and adults (21-31 years) use global prediction to shape adaptive CC over time. Specifically, the short-long percentage of S2 preparatory intervals was manipulated list-wide to create a slow-fast-slow-fast fixed block sequence and test how efficiently the response speed adapted accordingly. Overall, results revealed that in all groups behavioral performance is successfully adjusted as a function of global prediction in the late phase of the task (block 3 to 4). Remarkably, only adolescents and adults exhibit an early adaptation of adaptive CC (block 1 to 2), while children younger than 11 show sluggish ability in inferring implicit changes in global predictive rules. This age-related dissociation suggests that, although being present from an early age, adaptive CC based on global predictive information needs more developmental space to become flexible in an efficient way. In the light of a neuroconstructivist approach, we suggest that bottom-up driven implicit flexibility may represent a key prerequisite for the development of efficient explicit cognitive control.

Virtual Rejection and Overinclusion in Eating Disorders: An Experimental Investigation of the Impact on Emotions, Stress Perception, and Food Attitudes

(1) Background: the investigation of how interpersonal functioning affects eating psychopathology has been receiving increasing attention in the last decade. This study evaluates the impact of virtual social inclusion or ostracism on emotions, perceived stress, eating psychopathology, and the drive to binge or restrict in patients across the eating disorder spectrum. (2) Methods: a group of 122 adolescent and adult females with different eating disorder diagnoses were compared to 50 healthy peers with regards to their performance on, and responses to the Cyberball task, a virtual ball-tossing game. Each participant was randomly assigned to playing a social inclusion or a social exclusion block of the Cyberball task and completed self-report assessments of emotions, perceived stress and urge to restrict/binge before and after the task. (3) Results: patients with anorexia nervosa showed a more negative impact on psychological well-being evaluated with the need threat scale after the excluding block, while patients with bulimia nervosa reported more negative effects after the overincluding condition. Patients with binge eating disorder showed a reduction in specific negative emotions after the overincluding block, unlike all other participants. (4) Conclusions: findings show significant correlations between restraint thoughts in patients with bulimia nervosa and binge thoughts in patients with binge eating disorder after being exposed to the inclusion condition. Different reactions in cognitive and emotional states of patients with eating disorders after different interpersonal scenarios confirm the impact of inclusive or exclusive relationships on eating psychopathology, with specific and different responses across the eating disorder spectrum, that have been discussed, linked to their eating behavioral cognition.

Reliability of attention bias and attention bias variability to climate change images in the dot-probe task.

Climate change is one of the most pressing issues of the 21st century, which is perhaps why information about climate change has been found to capture observers' attention. One of the most common ways of assessing individual differences in attentional processing of climate change information is through the use of reaction time difference scores. However, reaction time-based difference scores have come under scrutiny for their low reliability. Given that a primary goal of the field is to link individual differences in attention processing to participant variables (e.g., environmental attitudes), we assessed the reliability of reaction time-based measures of attention processing of climate change information utilizing an existing dataset with three variations of the dot-probe task. Across all three samples, difference score-based measures of attentional bias were generally uncorrelated across task blocks (r = -0.25 to 0.31). We also assessed the reliability of newer attention bias variability measures that are thought to capture dynamic shifts in attention toward and away from salient information. Although these measures were initially found to be correlated across task blocks (r = 0.17-0.67), they also tended to be highly correlated with general reaction time variability (r = 0.49-0.83). When controlling for general reaction time variability, the correlations across task blocks for attention bias variability were much weaker and generally nonsignificant (r = -0.25 to 0.33). Furthermore, these measures were unrelated to pro-environmental disposition indicating poor predictive validity. In short, reaction time-based measures of attentional processing (including difference score and variability-based approaches) have unacceptably low levels of reliability and are therefore unsuitable for capturing individual differences in attentional bias to climate change information.

Attempting to counteract vigilance decrement in older adults with brain stimulation.

Against the background of demographic change and the need for enhancement techniques for an aging society, we set out to repeat a study that utilized 40-Hz transcranial alternating current stimulation (tACS) to counteract the slowdown of reaction times in a vigilance experiment but with participants aged 65 years and older. On an oscillatory level, vigilance decrement is linked to rising occipital alpha power, which has been shown to be downregulated using gamma-tACS. We applied tACS on the visual cortex and compared reaction times, error rates, and alpha power of a group stimulated with 40 Hz to a sham and a 5-Hz-stimulated control group. All groups executed two 30-min-long blocks of a visual task and were stimulated according to group in the second block. We hypothesized that the expected increase in reaction times and alpha power would be reduced in the 40-Hz group compared to the control groups in the second block (INTERVENTION). Statistical analysis with linear mixed models showed that reaction times increased significantly over time in the first block (BASELINE) with approximately 3 ms/min for the SHAM and 2 ms/min for the 5-Hz and 40-Hz groups, with no difference between the groups. The increase was less pronounced in the INTERVENTION block (1 ms/min for SHAM and 5-Hz groups, 3 ms/min for the 40-Hz group). Differences among groups in the INTERVENTION block were not significant if the 5-Hz or the 40-Hz group was used as the base group for the linear mixed model. Statistical analysis with a generalized linear mixed model showed that alpha power was significantly higher after the experiment (1.37 μV2) compared to before (1 μV2). No influence of stimulation (40 Hz, 5 Hz, or sham) could be detected. Although the literature has shown that tACS offers potential for older adults, our results indicate that findings from general studies cannot simply be transferred to an old-aged group. We suggest adjusting stimulation parameters to the neurophysiological features expected in this group. Next to heterogeneity and cognitive fitness, the influence of motivation and medication should be considered.

Role of frame structure in the development of KRS for learning dialogues.

Dialogues are building blocks of tasks and non-tasks of communication, which happen between objects in the universe. Each dialogue is a source of linguistic knowledge within a natural language that explains and elaborates with frame structure in general. In this paper, it is noticed that various forms like (nouns, pronouns, yes-no questions and deletion) are essential part of each dialogue structure (DSS) in Chandan’s work ਜੜਾਂ/Roots. With the help of frames, knowledge representation system (KRS) is prepared for such dialogues in Punjabi. On the other hand, it is argued that highest numbers of nouns are total 45 in DS2 and only 1 deletion case finds in DS3. While DS1 and DS2 both have similar number of 2-2 cases of yes-no questions. The overall evaluation is successfully matched with proposed an algorithm based on frames.

Slow tempo music preserves attentional efficiency in young children.

Past research has shown that listening to slow- or fast-tempo music can affect adults' executive attention (EA) performance. This study examined the immediate impact of brief exposure to slow- or fast-tempo music on EA performance in 4- to 6-year-old children. A within-subject design was used, where each child completed three blocks of theEA task after listening to fast-tempo music (fast-tempo block), slow-tempo music (slow-tempo block), and ocean waves (control block), with block-order counterbalanced. In each block, children were also asked to report their pre-task subjective emotional status (experienced arousal and valence) before listening to music and their post-task emotional status after the EA task. Three major results emerged. First, reaction time (RT) was significantly faster in the slow-tempo block than in the fast-tempo, suggesting that listening to slow-tempo music preserves processing efficiency, relative to fast-tempo music. Second, children's accuracy rate in the EA task did not differ across blocks. Third, children's subjective emotional status did not differ across blocks and did not change across the pre- and post-task phases in any block, suggesting the faster RT observed in the slow-tempo block cannot be explained by changes in arousal or mood.

Interaction Between Memory Load and Experimental Design on Brain Connectivity and Network Topology.

The conventional approach to investigating functional connectivity in the block-designed study usually concatenates task blocks or employs residuals of task activation. While providing many insights into brain functions, the block design adds more manipulation in functional network analysis that may reduce the purity of the blood oxygenation level-dependent signal. Recent studies utilized one single long run for task trials of the same condition, the so-called continuous design, to investigate functional connectivity based on task functional magnetic resonance imaging. Continuous brain activities associated with the single-task condition can be directly utilized for task-related functional connectivity assessment, which has been examined for working memory, sensory, motor, and semantic task experiments in previous research. But it remains unclear how the block and continuous design influence the assessment of task-related functional connectivity networks. This study aimed to disentangle the separable effects of block/continuous design and working memory load on task-related functional connectivity networks, by using repeated-measures analysis of variance. Across 50 young healthy adults, behavioral results of accuracy and reaction time showed a significant main effect of design as well as interaction between design and load. Imaging results revealed that the cingulo-opercular, fronto-parietal, and default model networks were associated with not only task activation, but significant main effects of design and load as well as their interaction on intra- and inter-network functional connectivity and global network topology. Moreover, a significant behavior-brain association was identified for the continuous design. This work has extended the evidence that continuous design can be used to study task-related functional connectivity and subtle brain-behavioral relationships.

Reinforcement learning profiles and negative symptoms across chronic and clinical high-risk phases of psychotic illness.

Negative symptoms are prominent in individuals with schizophrenia (SZ) and youth at clinical high-risk for psychosis (CHR). In SZ, negative symptoms are linked to reinforcement learning (RL) dysfunction; however, previous research suggests implicit RL remains intact. It is unknown whether implicit RL is preserved in the CHR phase where negative symptom mechanisms are unclear, knowledge of which may assist in developing early identification and prevention methods. Participants from two studies completed an implicit RL task: Study 1 included 53 SZ individuals and 54 healthy controls (HC); Study 2 included 26 CHR youth and 23 HCs. Bias trajectories reflecting implicit RL were compared between groups and correlations with negative symptoms were examined. Cluster analysis investigated RL profiles across the combined samples. Implicit RL was comparable between HC and their corresponding SZ and CHR groups. However, cluster analysis was able to parse performance heterogeneity across diagnostic boundaries into two distinct RL profiles: a Positive/Early Learning cluster (65% of participants) with positive bias scores increasing from the first to second task block, and a Negative/Late Learning cluster (35% of participants) with negative bias scores increasing from the second to third block. Clusters did not differ in the proportion of CHR vs. SZ cases; however, the Negative/Late Learning cluster had more severe negative symptoms. Although implicit RL is intact in CHR similar to SZ, distinct implicit RL phenotypic profiles with elevated negative symptoms were identified trans-phasically, suggesting distinct reward-processing mechanisms can contribute to negative symptoms independent of phases of illness.

Removal of reinforcement improves instrumental performance in humans by decreasing a general action bias rather than unmasking learnt associations.

Performance during instrumental learning is commonly believed to reflect the knowledge that has been acquired up to that point. However, recent work in rodents found that instrumental performance was enhanced during periods when reinforcement was withheld, relative to periods when reinforcement was provided. This suggests that reinforcement may mask acquired knowledge and lead to impaired performance. In the present study, we investigated whether such a beneficial effect of removing reinforcement translates to humans. Specifically, we tested whether performance during learning was improved during non-reinforced relative to reinforced task periods using signal detection theory and a computational modelling approach. To this end, 60 healthy volunteers performed a novel visual go/no-go learning task with deterministic reinforcement. To probe acquired knowledge in the absence of reinforcement, we interspersed blocks without feedback. In these non-reinforced task blocks, we found an increased d', indicative of enhanced instrumental performance. However, computational modelling showed that this improvement in performance was not due to an increased sensitivity of decision making to learnt values, but to a more cautious mode of responding, as evidenced by a reduction of a general response bias. Together with an initial tendency to act, this is sufficient to drive differential changes in hit and false alarm rates that jointly lead to an increased d'. To conclude, the improved instrumental performance in the absence of reinforcement observed in studies using asymmetrically reinforced go/no-go tasks may reflect a change in response bias rather than unmasking latent knowledge.

Complex response inhibition and cognitive flexibility in school-aged Cypriot-Greek-speaking children who stutter.

Over the last few years, research findings have suggested limitations in executive function (EF) of children who stutter (CWS) with the evidence being more consistent in studies with preschoolers (3-6 years old) than in studies with school-aged children (6-12 years old). The purpose of the current study was to assess complex response inhibition and cognitive flexibility in school-aged CWS and their non-stuttering peers. Participants, 19 CWS (mean age = 7.58 years, range 6.08-9.17) and 19 age-and gender-matched children who do not stutter (CWNS; mean age = 7.58 years, range 6.08-9.33), completed a visual task consisting of three task blocks. Analyses were based on response times and error percentages during the different task blocks. All participants showed expected performance-costs in task block comparisons targeting complex response inhibition and cognitive flexibility. Significant group differences were found in measures of cognitive flexibility with CWS performing slower compared to CWNS (p = 0.02). Additionally, significant block × group interactions demonstrated that CWS, compared to CWNS, slowed down more (i.e., higher performance-cost) under both complex response inhibition (p = 0.049) and cognitive flexibility task conditions (p = 0.04 for no-set-shifting and p = 0.02 for set-shifting). These results are in line with some of the previous findings in school-aged CWS and suggest that CWS present lower performance in complex response inhibition and cognitive flexibility task conditions when compared to their non-stuttering peers.

Late dominance of the right hemisphere during narrative comprehension

PET and fMRI studies suggest that auditory narrative comprehension is supported by a bilateral multilobar cortical network. The superior temporal resolution of magnetoencephalography (MEG) makes it an attractive tool to investigate the dynamics of how different neuroanatomic substrates engage during narrative comprehension. Using beta-band power changes as a marker of cortical engagement, we studied MEG responses during an auditory story comprehension task in 31 healthy adults. The protocol consisted of two runs, each interleaving 7 blocks of the story comprehension task with 15 blocks of an auditorily presented math task as a control for phonological processing, working memory, and attention processes. Sources at the cortical surface were estimated with a frequency-resolved beamformer. Beta-band power was estimated in the frequency range of 16–24 Hz over 1-sec epochs starting from 400 msec after stimulus onset until the end of a story or math problem presentation. These power estimates were compared to 1-second epochs of data before the stimulus block onset. The task-related cortical engagement was inferred from beta-band power decrements. Group-level source activations were statistically compared using non-parametric permutation testing. A story-math contrast of beta-band power changes showed greater bilateral cortical engagement within the fusiform gyrus, inferior and middle temporal gyri, parahippocampal gyrus, and left inferior frontal gyrus (IFG) during story comprehension. A math-story contrast of beta power decrements showed greater bilateral but left-lateralized engagement of the middle frontal gyrus and superior parietal lobule. The evolution of cortical engagement during five temporal windows across the presentation of stories showed significant involvement during the first interval of the narrative of bilateral opercular and insular regions as well as the ventral and lateral temporal cortex, extending more posteriorly on the left and medially on the right. Over time, there continued to be sustained right anterior ventral temporal engagement, with increasing involvement of the right anterior parahippocampal gyrus, STG, MTG, posterior superior temporal sulcus, inferior parietal lobule, frontal operculum, and insula, while left hemisphere engagement decreased. Our findings are consistent with prior imaging studies of narrative comprehension, but in addition, they demonstrate increasing right-lateralized engagement over the course of narratives, suggesting an important role for these right-hemispheric regions in semantic integration as well as social and pragmatic inference processing.

Using visual speech at the cocktail-party: CNV evidence for early speech extraction in younger and older adults

The comprehension of spoken language benefits from visual speech information. One reason for this is the temporal lead of mouth and lip movements over the onset of acoustic speech utterance. Here, we investigated EEG event-related potentials preceding acoustic speech, focusing on a fronto-central contingent negative variation (CNV) prior to the onset of acoustic speech. We explored influences of expectation and visual speech content as well as age-related differences. In a multi-talker two-alternative speech discrimination task, younger and older subjects responded to short words presented simultaneously to competing speech under free-field conditions. Subjects were always presented with audiovisual speech stimuli, while the modality containing the task-relevant information was modulated in a block-wise fashion. Thus, task-relevant speech information was either available as audio-visually congruent stimuli or only in the visual (visual-valid) or the auditory (auditory-valid) modality. Subjects were instructed to fixate a pre-specified position in the left or right hemispace. In each task block, task-relevant stimuli appeared either at the pre-specified position (standard trials, 80%) or at a rare deviant position (20%). Target words were recognized faster and more accurately when visual speech information was available. The CNV prior to the acoustic speech onset was more pronounced with visual-informative than with visually non-informative speech. Especially in the younger group, a less pronounced CNV occurred with purely visual speech in deviant trials, that is, when a task-irrelevant speech stimulus appeared instead of the expected target stimulus. The results indicate that processes preceding the onset of acoustic speech are modulated by expectations and visual speech content, while age differences are rather small.

Становление учебного действия сравнения на уроках литературного чтения в третьем-четвёртом классах

The article presents a practice-oriented methodological material on the formation of a universal cognitive learning action of comparison by means of literary reading in junior schoolchildren of the third and fourth grades. Three blocks of tasks aimed at developing students' skills to compare literary texts are described. The author pays special attention to the characteristics of creative tasks that contribute to the formation of positive motivation in younger students to master the content of the subject "Literary reading".

Two-point discrimination responses in children with idiopathic toe walking: A feasibility fMRI study.

Idiopathic toe walking (ITW) is a diagnosis given to children who walk with an absence or limitation of heel strike in the contact phase of the gait cycle, that are otherwise typically developing. There is emerging evidence that this gait pattern may occur in children who experience tactile sensory processing challenges. This feasibility study aimed to determine if children were able to respond to a sensory stimulus during a fMRI. Children aged between 8-16 years of age, with and without idiopathic toe walking were recruited from general public advertising. Participants were required to perform a two-point discrimination test (task block) and press a button without being tested (control block) during an fMRI using a standard block design. Activation differences were examined in the left frontal pole, left supramarginal gyrus, left parahippocampal gyrus, left paracingulate gyrus and the right superior temporal. Five children were in the typically developing (TD) group and three were in the ITW group. There were between-group activation differences in the decision-making block compared to the control block in the left frontal lobe, parahippocampal gyrus and the right superior temporal gyrus. There was greater variation in activation in the left supramarginal gyrus and the left paracingulate gyrus in the ITW group compared to the typically developing group. Based on this study a future sample size of 15 children per group will be required to detect an adequate effect across chosen regions of interest Conducting fMRI using two-point discrimination testing on this population is feasible. Further research is required with larger population sizes to determine if brain activation patterns during the sensory input decision-making process are different in this population.

Analysis of Human Whole-Body Joint Torques During Overhead Work With a Passive Exoskeleton

Overheadwork is classifiedas one of the major risk factors for the onset of shoulder work-related musculoskeletal disorders and muscle fatigue. Upper-limb exoskeletons can be used to assist workers during the execution of industrial overhead tasks to prevent such disorders. Twelve novice participants have been equipped with inertial and force/torque sensors to simultaneously estimate the whole-body kinematics and the joint torques (i.e., internal articular stress) by means of a probabilistic estimator, while performing an overhead task with a pointing tool. An evaluation has been performed to analyze the effect at the whole-body level by considering the conditions of wearing and not-wearing PAEXO, a passive exoskeleton for upper-limb support during overhead work. Results point out that PAEXO provides a reduction of the whole-body joint effort across the experimental task blocks (from 66% to 86%). Moreover, the analysis along with five different body areas shows that 1) the exoskeleton provides support at the human shoulders by reducing the joint effort at the targeted limbs, and 2) that part of the internal wrenches is intuitively transferred from the upper body to the thighs and legs, which is shown with an increment of the torques at the legs joints. The promising outcomes show that the probabilistic estimation algorithm can be used as a validation metric to quantitatively assess PAEXO performances, paving thus the way for the next challenging milestone, such as the optimization of the human joint torques via adaptive exoskeleton control.

Удосконалення спеціальних якостей військовослужбовців засобами фізичного виховання

At the stage of development and reform of the Armed Forces of Ukraine, physical training is an important and integral part of military training and education of personnel. It is aimed at ensuring the physical readiness of military personnel for military activities and is designed to contribute to solving other tasks of training and education.The current state and conduct of hostilities in the state requires professionally trained specialists in the Armed Forces, capable of productively solving tasks in various issues. The solution of these tasks involves the inclusion in various forms of physical training of special complexes invested in increasing the functional capacity of cadets. The purpose of the work is to practically justify the effectiveness of the application of complex military-applied tasks at the professional-applied stage of the development of the physical qualities of cadets on the example of training of military specialists at the Military Academy. Research material and methods. To achieve this goal, a complex of scientific research methods was applied, namely: general scientific (analysis of scientific and methodical literature), pedagogical (testing, experiment), sociological (written survey using a questionnaire), mathematical statistics methods. 32 cadets of the National Academy of Land Forces named after Hetman Pyotr Sahaidachny, ages 19-20, took part in the study. The results. The conducted studies objectively show that classes held twice a week for 90 minutes with the use in the educational and training process of developed blocks of complex military-applied tasks on various topics of physical training, aimed at the manifestation of general and special endurance and special qualities, have a positive effect on the physical. Conclusions. It was established that the complex tasks of the military-applied direction are the starting element of the microstructure of the educational session. It can be argued that the quality and effectiveness of the educational and training process largely depend on the selection and construction of the most optimal blocks of complex tasks, appropriate workloads, task performance modes, a promising model of professional activity that takes into account other training factors. The identification of the main influential components of complex tasks leads to the implementation of purposeful and effective management of the current state of cadets, and in the complex both physical and professional-applied preparedness

Influence of Heat Exposure on Motor Control Performance and Learning as Well as Physiological Responses to Visuomotor Accuracy Tracking Task.

This study aimed to determine whether heat exposure attenuates motor control performance and learning, and blunts cardiovascular and thermoregulatory responses to visuomotor accuracy tracking (VAT) tasks. Twenty-nine healthy young adults (22 males) were divided into two groups performing VAT tasks (5 trials × 10 blocks) in thermoneutral (NEUT: 25 °C, 45% RH, n = 14) and hot (HOT: 35 °C, 45% RH, n = 15) environments (acquisition phase). One block of the VAT task was repeated at 1, 2, and 4 h after the acquisition phase (retention phase). Heat exposure elevated skin temperature to ~3 °C with a marginally increased core body temperature. VAT performance (error distance of curve tracking) was more attenuated overall in HOT than in NEUT in the acquisition phase without improvement in magnitude alteration. Heat exposure did not affect VAT performance in the retention phase. The mean arterial blood pressure and heart rate, but not for sweating and cutaneous vascular responses to VAT acquisition trials, were more attenuated in HOT than in NEUT without any retention phase alternations. We conclude that skin temperature elevation exacerbates motor control performance and blunts cardiovascular response during the motor skill acquisition period. However, these alternations are not sustainable thereafter.

Resting state electroencephalographic rhythms are affected by immediately preceding memory demands in cognitively unimpaired elderly and patients with mild cognitive impairment.

Experiments on event-related electroencephalographic oscillations in aged people typically include blocks of cognitive tasks with a few minutes of interval between them. The present exploratory study tested the effect of being engaged on cognitive tasks over the resting state cortical arousal after task completion, and whether it differs according to the level of the participant's cognitive decline. To investigate this issue, we used a local database including data in 30 healthy cognitively unimpaired (CU) persons and 40 matched patients with amnestic mild cognitive impairment (aMCI). They had been involved in 2 memory tasks for about 40 min and underwent resting-state electroencephalographic (rsEEG) recording after 5 min from the task end. eLORETA freeware estimated rsEEG alpha source activity as an index of general cortical arousal. In the CU but not aMCI group, there was a negative correlation between memory tasks performance and posterior rsEEG alpha source activity. The better the memory tasks performance, the lower the posterior alpha activity (i.e., higher cortical arousal). There was also a negative correlation between neuropsychological test scores of global cognitive status and alpha source activity. These results suggest that engagement in memory tasks may perturb background brain arousal for more than 5 min after the tasks end, and that this effect are dependent on participants global cognitive status. Future studies in CU and aMCI groups may cross-validate and extend these results with experiments including (1) rsEEG recordings before memory tasks and (2) post-tasks rsEEG recordings after 5, 15, and 30 min.