Getting to the heart of personality in early childhood: Cardiac electrophysiology and stability of temperament

Can detection of highly stable individual differences in temperament in early childhood be enhanced using measures of resting heart rate (HR) and respiratory sinus arrhythmia (RSA)? The current longitudinal study (N = 216, 50% female; two to four years old) tested the statistical moderating effects of longitudinal change in resting HR and RSA on stability of mother-rated temperament. Children with the smallest decreases in resting HR and smallest increases in resting RSA had the most stable individual differences in effortful control. In contrast, those with the largest increases in resting RSA had the most stable individual differences in surgency. Including information on HR and RSA can be useful, though the effects depend on the trait and physiological indicator in question.     

The role of perceived physiological activity in affective judgments

This study assessed the physiological and cognitive effects of Valins' (Valins, S. Journal of Personality and Social Psychology, 1966, 4, 400–408) false heart rate procedure. Twenty-two male subjects were exposed to two feedback conditions during which measures of actual heart rate and skin conductance were obtained. In each condition, eight slides of nude females were presented; some slides were associated with false heart rate increases, while for other slides the feedback remained stable. In one condition, subjects were told that the heart rate was that of another subject; in the other condition, subjects were told that the feedback was their own heart rate. In both conditions, subjects judged the attractiveness of the slides from their own point of view and from the point of view of the other subject. Slides associated with false heart rate increases were rated as more attractive than stable slides when subjects (1) heard their own heart rate and rated their own attraction; (2) heard the other subject's heart rate and rated their own attraction; and (3) heard the other subject's heart rate and rated the other subject's attraction. Skin conductance responses and actual cardiac decelerations were greater when subjects heard what was allegedly their own heart rate and when the slides were accompanied by apparent cardiac acceleration. However, these actual physiological responses did not play a causal role in relation to the affective judgments. Instead, the relationship between perceived physiological changes and feelings of attractiveness was mediated by cognitive processes associated with informational and directive influences of the feedback.     

Motivation towards closure and cognitive processes: An individual differences approach

Two studies (N = 212) examined the relationships between elementary cognitive processes and individual differences in the need for cognitive closure. The results indicated that the need for closure is linked with certain cognitive deficits, specifically a restricted pool of cognitive resources allocated to a current activity. It was also found that these cognitive limitations tend to be compensated for by a particularly efficient process of information-selection from the environment. However, the selection process is costly, thus in a situation of drainage of cognitive resources its effectiveness also drops and the selection advantage of high (vs. low) need for closure individuals is eliminated.     

Psychophysiological response to cognitive workload during symmetrical,asymmetrical and dual-task walking

Walking with a lower limb prosthesis comes at a high cognitive workload for amputees, possibly affecting their mobility, safety and independency. A biocooperative prosthesis which is able to reduce the cognitive workload of walking could offer a solution. Therefore, we wanted to investigate whether different levels of cognitive workload can be assessed during symmetrical, asymmetrical and dual-task walking and to identify which parameters are the most sensitive. Twenty-four healthy subjects participated in this study. Cognitive workload was assessed through psychophysiological responses, physical and cognitive performance and subjective ratings. The results showed that breathing frequency and heart rate significantly increased, and heart rate variability significantly decreased with increasing cognitive workload during walking (p < .05). Performance measures (e.g., cadence) only changed under high cognitive workload. As a result, psychophysiological measures are the most sensitive to identify changes in cognitive workload during walking. These parameters reflect the cognitive effort necessary to maintain performance during complex walking and can easily be assessed regardless of the task. This makes them excellent candidates to feed to the control loop of a biocooperative prosthesis in order to detect the cognitive workload. This information can then be used to adapt the robotic assistance to the patient’s cognitive abilities.     

Structural brain abnormalities in patients with Parkinson’s disease with visual hallucinations: A comparative voxel-based analysis

The objective is to evaluate clinical characteristics and cerebral alterations in Parkinson’s disease (PD) patients with diurnal visual hallucinations (VHs). Assessment was performed using magnetic resonance image (MRI) and voxel-based morphometry (VBM). Thirty-nine patients with PD (53.8%) and ten controls were studied. Voxel based morphology analysis was performed. Eleven patients presented diurnal VHs and among these, six had cognitive dysfunction. Patients with VHs performed worse in the mentation-related UPDRS I (p = 0.005) and motor-related UPDRS III (p = 0.02). Patients with VHs showed significant clusters of reduced grey matter volume compared to controls in the left opercula frontal gyrus and left superior frontal gyrus. PD without hallucinations demonstrated reduced grey matter volume in the left superior frontal gyrus compared to controls. Comparisons between patients with VHs regarding the presence of cognitive dysfunction showed that cases with cognitive dysfunction as compared to those without cognitive dysfunction showed significant clusters of reduced grey matter volume in the left opercular frontal gyrus. Cases without cognitive dysfunction had reduced grey matter substance in the left insula and left trigonal frontal gyrus. Judging from our findings, an abnormal frontal cortex, particularly left sided insula, frontal opercular, trigonal frontal gyrus and orbital frontal would make PD patients vulnerable to hallucinations. Compromise of the left operculum distinguished cases with VHs and cognitive dysfunction. Our findings reinforce the theoretical concept of a top-down visual processing in the genesis of VHs in PD.     

Perceiving red decreases motor performance over time: A pilot study

IntroductionColors may influence motor performance.ObjectiveThe present study aimed to compare the effects of perception of red and green environments on physical (performance and heart rate) and psychological (perceived effort, anxiety and enjoyment) parameters during cycling trials.MethodTen cyclists achieved two identical series of three randomized 7-minute trials on home trainers, during which they were continuously exposed to red, green, and gray environments. Covered distance and heart rate were recorded during each trial, after which participants answered items intended to assess perceived effort, anxiety, and enjoyment experienced during the trial.ResultsResults showed that covered distance (ps ≤ .02) and heart rate (ps ≤ .03) were lower in the red environment than in the gray and green environments. Enjoyment was higher in the green environment than in the red environment (p = .006). The colored environments did not influence perceived effort and anxiety (ps > .05).ConclusionThis study is the first to show that perceiving red is detrimental for motor performance over an extended period of time.     

Reaction time and established risk factors for total and cardiovascular disease mortality: Comparison of effect estimates in the follow-up of a large, UK-wide, general-population based survey

Higher cognitive function is associated with faster choice reaction time (CRT), and both are associated with a reduced risk of mortality from all-causes and cardiovascular disease (CVD). However, comparison of the predictive capacity of CRT, an emerging risk factor, with that for established ‘classic’ risk factors for mortality, such as smoking, hypertension or obesity, is lacking. The purpose of this study was to compare the relative impact of CRT with a range of established risk factors for all-cause and CVD mortality. The UK Health and Lifestyle Survey (HALS) is a national sample survey of adults in England, Scotland, and Wales. In 1984/85, data on lifestyle factors, socioeconomic status, and health were collected for 9003 individuals. CRT data were available for 7414 individuals. With different predictor variables having differing coding structures, we used the relative index of inequality (RII) to explore the relation of a range of risk factors with mortality by computing the risk in disadvantaged (high risk; e.g., smokers) relative to advantaged (low risk; e.g., non-smokers) persons. During an average of 20 years of follow-up, there were 1289 deaths (568 ascribed to CVD). In age- and sex-adjusted models in which all-cause mortality was the outcome of interest, CRT mean (RII = 2.57, 95% CI = 1.98, 3.33) was the second most important predictor of death after smoking (RII = 3.03, 95% CI = 2.45, 3.75). For death from CVD, CRT mean (RII = 2.31, 95% CI = 1.55, 3.43) was again the second most important risk factor for death, behind systolic blood pressure (RII = 4.37, 95% CI = 3.03, 6.29). These analyses suggest that CRT, a moderately high correlate of intelligence, is an important risk factor for death from all-causes and CVD.     

Investigating the acute effect of an aerobic dance exercise program on neuro-cognitive function in the elderly

ObjectiveThe present study investigated the types of aerobic dance programs that positively impact cognition, such as executive function, in elderly people.DesignRandomized controlled trial.MethodThe study compared the effects of acute aerobic dance exercise on cognitive performance using two 40-min aerobic dance programs. Thirty-four elderly participants, aged 65–75 years, were randomly assigned into either free (N = 17) or combination (N = 17) style workout groups. The free style (FR) workout consisted of several patterns of movement, while the combination style (CB) workout consisted of similar patterns of movement to FR, but the patterns were joined to form a long choreographic routine. Both dance programs were controlled to be the same in exercise intensity, approximately 40% heart rate reserve. Reaction time and correct rates were measured using a task-switching reaction time test to evaluate executive cognitive performance immediately before and after the 40-min dance exercise.ResultsA two-way (dance program × pre-post dance exercise) repeated-measures analysis of variance for switch reaction time increase (switch cost) demonstrated a significant interaction (p = .006), showing that the switch cost in the CB group became smaller after the dance exercise than before (p = .009).ConclusionThe results suggest that the executive cognitive network was facilitated in a CB dance workout that has a dual-task nature and induces movement (task) interference with unexpected movement changes.     

Assessing the impact of dual-task reactive step practice in people with Parkinson's disease: A feasibility study

Reactive stepping is impaired in people with Parkinson's Disease (PD) but can be improved with training. However, it is unclear if reactive steps can be improved when performing a concurrent cognitive task, a common and fall-relevant circumstance. We assessed the feasibility and preliminary effectiveness of dual-task reactive step training. Specifically, we measured whether stepping and cognitive reaction time are improved after one day of dual-task reactive step practice and if improvements are retained 24 h later. Sixteen people with PD and 13 age-matched healthy controls (HC) underwent repeated from-stance support surface perturbations that elicited a reactive step while performing an auditory Stroop task. Participants returned the following day to reassess dual-task reactive stepping performance. Cognitive, neuromuscular, and stepping outcomes were calculated. Increased step lengths were observed for both groups after practice (p < 0.001). Cognitive reaction times also improved through practice; however, this was more pronounced in the HC group (group by time interaction- p < 0.001). No changes were observed for step latency, margin of stability, or EMG onset through practice. Step length and cognitive reaction time improvements were retained 24 h after practice in both groups (step length: p < 0.001; cognitive reaction time: p = 0.05). This study provides preliminary evidence for the effectiveness of dual-task reactive step training to improve step length in people with PD. The improvements in step length without compromising cognitive reaction times suggest that participants improved reactive stepping without a robust attention shift toward the postural task. Future research is necessary to determine optimal training protocols and determine if such training protocols impact falls in PD patients.     

Influence of cognitive and motor tasks using smartphone during gait: EMG and gait performance analysis – Dual-task study

Previous studies reported changes in spatiotemporal gait parameters during dual-task performance while walking using a smartphone compared to walking without a smartphone. However, studies that assess muscle activity while walking and simultaneously performing smartphone tasks are scarce. So, this study aimed to assess the effects of motor and cognitive tasks using a smartphone while simultaneously performing gait on muscle activity and gait spatiotemporal parameters in healthy young adults. Thirty young adults (22.83 ± 3.92 years) performed five tasks: walking without a smartphone (single-task, ST); typing on a smartphone keyboard in a sitting position (secondary motor single-task); performing a cognitive task on a smartphone in a sitting position (cognitive single-task); walking while typing on a smartphone keyboard (motor dual-task, mot-DT) and walking while performing a cognitive task on a smartphone (cognitive dual-task, cog-DT). Gait speed, stride length, stride width and cycle time were collected using an optical motion capture system coupled with two force plates. Muscle activity was recorded using surface electromyographic signals from bilateral biceps femoris, rectus femoris, tibialis anterior, gastrocnemius medialis, gastrocnemius lateralis, gluteus maximus and lumbar erector spinae. Results showed a decrease in stride length and gait speed from the single-task to cog-DT and mot-DT (p < 0.05). On the other hand, muscle activity increased in most muscles analyzed from single- to dual-task conditions (p < 0.05). In conclusion, performing a cognitive or motor task using a smartphone while walking promote a decline in spatiotemporal gait parameters performance and change muscle activity pattern compared to normal walking.     

Action versus state orientation moderates the relation between executive function task performance and resting heart rate variability

Despite a considerable rationale for a relationship between executive functions (EFs) and resting heart rate variability based on the neurovisceral integration model, meta-analyses reveal relatively small effect sizes. This study aims to evaluate this relationship in three EF tasks by taking task characteristics and implicit affect and attention regulation measured by action-state orientation into account. Analyzing 154 participants (M = 23.56 years; SD = 3.14) indicated that the relationship was moderated by action-state orientation. However, the Johnson-Neyman test only found a relationship for state-oriented individuals, which also differed in the direction between demanding and low-demanding tasks. Therefore, this study cannot fully confirm the neurovisceral integration model. Implications for future research are discussed.     

Acute exercise and children’s cognitive functioning: What is the optimal dose of cognitive challenge?

Acute bouts of exercise have the potential to benefit children’s cognition. Inconsistent evidence on the role of qualitative exercise task characteristics calls for further investigation of the cognitive challenge level in exercise. Thus, the study aim was to investigate which “dose” of cognitive challenge in acute exercise benefits children’s cognition, also exploring the moderating role of individual characteristics. In a within-subject experimental design, 103 children (M_age = 11.1, SD = 0.9, 48% female) participated weekly in one of three 15-min exergames followed by an Attention Network task. Exergame sessions were designed to keep physical intensity constant (65% HR_max) and to have different cognitive challenge levels (low, mid, high; adapted to the ongoing individual performance). ANOVAs performed on variables that reflect the individual functioning of attention networks revealed a significant effect of cognitive challenge on executive control efficiency (reaction time performances; p = .014, ƞ²_p = .08), with better performances after the high-challenge condition compared to lower ones (ps < .015), whereas alerting and orienting were unaffected by cognitive challenge (ps > .05). ANOVAs performed on variables that reflect the interactive functioning of attention networks revealed that biological sex moderated cognitive challenge effects. For males only, the cognitive challenge level influenced the interactive functioning of executive control and orienting networks (p = .004; ƞ²_p = .07). Results suggest that an individualized and adaptive cognitively high-challenging bout of exercise is more beneficial to children’s executive control than less challenging ones. For males, the cognitive challenge in an acute bout seems beneficial to maintain executive control efficiency also when spatial attention resources cannot be validly allocated in advance. Results are interpreted referring to the cognitive stimulation hypothesis and arousal theory.     

Proneness for exercise,cognitive and psychophysiological consequences of action observation

ObjectivesPhysical exercise has benefits that go beyond health and well-being, namely in cognitive, motor and psychophysiological areas. The discovery of a shared neural network between action observation and execution (Action-Observation Network) led us to hypothesize that watching human motor action might improve cognitive and motor aspects of performance and proneness for exercise.Design/MethodsSixty participants viewed a Motor (M) (n = 30) or a Non-Motor (NM) (n = 30) movie with strong or weak content of motoric features of human action, respectively. Performance in d2 Attention test, Fitts' Motor task, and a Proneness for Exercise Visual Analog Scale was assessed before and after movie visualization, in a cross-sectional study. Psychophysiological measures were recorded throughout the experiment.ResultsOur results demonstrate an increase in proneness for exercise, and greater improvement in attention-related cognitive aspects in the M group. The aforementioned benefits of action observation did not modulate motor performance. A mental effort deployment was associated to the decrease in heart rate variability after visualization of the NM movie. This was not conducive to attention channeling on task performance. Conversely, M movie observation seemed to be associated to a cognitive load release, affording attention deployment for the resolution of the subsequent tasks.ConclusionsIt seems that some benefits associated to physical practice can result from the mere visualization of movies with human motor action content. These are the improvement in attention-related cognitive skills associated to psychophysiological changes that support a disengagement from mental effort. Crucially, the observation of exercise behavior seems to be a key factor for exercise adherence.     

Three consecutive nights of sleep loss: Effects of morning caffeine consumption on subjective sleepiness/alertness,reaction time and simulated driving performance

Caffeinated products are often consumed as a popular countermeasure to the effects of sleep loss. However, the efficacy of caffeine to exert these effects after consecutive nights of sleep loss is poorly understood. The aim of this study was to investigate the effects of three consecutive nights of restricted sleep and morning caffeine consumption on subjective ratings of sleepiness/alertness, reaction time, and simulated driving performance. Twenty healthy, habitual caffeine consumers (11 females; age: 23.3 ± 5.7 y; BMI: 22.3 ± 3.5 kg⋅m⁻²; caffeine intake: 204 ± 89 mg⋅day⁻¹; Mean ± SD) who had normal sleeping patterns (≥8 h⋅night⁻¹) participated in this double-blind, placebo-controlled, randomised study. Following one night of normal sleep (≥8 h time in bed (TIB)), participants underwent three consecutive nights of restricted sleep (5 h TIB). Participants received caffeine (200 mg; n = 10) or placebo (n = 10) capsules each morning and all participants received caffeine (100 mg) capsules each afternoon. Subjective ratings of alertness, concentration and tiredness were measured before and 1 h after morning capsule administration. Choice Reaction Time (CRT) was examined 1 h after morning capsule administration, with response speed and accuracy as outcome variables. Driving performance was assessed using a 30 min simulated driving task, with lateral (standard deviation of lane position [SDLP]; total number of line crossings [LC]) and longitudinal (standard deviation of speed [SDSP]) measures of vehicle control as outcome variables. Alertness and concentration significantly decreased, and tiredness increased across the three days of sleep loss. Caffeine only marginally alleviated these effects. No differences were observed between treatments or across trial days for response speed and accuracy on the CRT task. Likewise, no significant differences were observed between groups or across trial days for any measures of simulated driving performance. Overall, results from this study indicate that three consecutive days of sleep loss influence subjective ratings of alertness, concentration and tiredness, but does not alter CRT or simulated driving performance. Caffeine may alleviate some of the negative subjective effects imposed by restricted sleep, but the efficacy of caffeine to attenuate performance changes in CRT and driving performance were unable to be observed.     

Evaluation of cognitive behavior among deaf subjects with video game as intervention

Previous research on video gaming mainly focused on negative impact on users. In this study, the positive impact of action video gaming among congenitally deaf subjects is investigated. Subjects possessed high level of visual information processing capacity. A 96 h of action video game play resulted in the improvement of mean reaction time (mRT) (post = 413.21 ms, pre = 453.39 ms) and certain cognitive functions. Higher heart rate variability (HRV) subjects demonstrated faster and significant improvement in mRT (p < 0.0045) after intervention. The α and β EEG band powers were found increased in parietal (6.33%, 4.28%) and occipital (8.38%, 38%) lobes respectively. The θ band power increased in frontal (32%) and parietal (13%) lobes. These results can reflect enhancement in certain cognitive performances such as visual perception, attention, memory, and motor skills. The ratio index β/(α + θ) increased in frontal and occipital lobes while β/θ increased in frontal and temporal lobes. These results may also suggest improvements in attention processing capacity and neural activity. These results implies improvements in certain aspects of cognition among deaf subjects. However, to validate these results a further study on larger number of samples with advanced computerized cognitive battery testing can be employed.     

Effects of age simulation and age on motor sequence learning: Interaction of age-related cognitive and motor decline

Aging is known to lead to decrements in sensory and cognitive functioning and motor performance. The purpose of the present experiment was twofold: a) We assessed the influence of wearing an age simulation suit on motor sequence learning, cognitive speed tasks and far visual acuity in healthy, younger adults. b) We evaluated the interaction of cognitive aging and declining motor sequence learning in older adults. In a between-subjects design we tested 11 younger adults (M_age = 23.6 years) without the age suit, 12 younger adults wearing the age suit (M_age = 23.2 years), and 23 older adults (M_age = 72.6 years). All participants learned a simple, spatial-temporal movement sequence on two consecutive days, and we assessed perceptual processing speed (Digit Symbol Substitution test and Figural Speed test) and far visual acuity. Wearing an age simulation suit neither affected the learning of the simple motor sequence nor the performance at the cognitive speed tasks in younger adults. However, far visual acuity suffered from wearing the suit. Younger adults with and without the suit showed better motor sequence learning compared to older adults. The significant correlations between the cognitive speed tests and the motor learning performance in older adults indicated that cognitive aging partially explains some of the variance in age-related motor learning deficits.     

Higher chronic psychological stress is associated with blunted affective responses to strenuous resistance exercise: RPE,pleasure, pain

The aim of this study was to determine whether mental stress moderates perceptions of muscular pain, exertion, pleasure and arousal during a bout of strenuous resistance exercise. Two hundred and ten undergraduate students recruited from resistance exercise classes were screened with the Perceived Stress Scale (PSS). Fifty-seven individuals (age = 20.1 ± 1.2 y) were invited to complete the Undergraduate Stress Questionnaire (USQ), a measure of life event stress, and fitness testing. They later performed a two-phase, acute heavy-resistance exercise protocol: first phase: 10-repetition maximum (RM) leg press test; second phase: six sets at 80–100% of 10-RM. During exercise, participants responded to the Feeling Scale (pleasure), Felt Arousal Scale, Omni-RPE and the Pain Intensity Scale. Affective responses and heart rate were analyzed with a hierarchical linear modeling (HLM) growth curve analysis. USQ moderated the trajectories of affective responses and heart rate during exercise. Higher stress (USQ) levels were significantly related to lower rise in RPE (time², p = .002; time³, p < .001) and heart rate (time², p < .001; time³, p < .001). USQ had a main effect on pleasure and arousal (p values < .001), in which higher levels of stress were related to less affect. Models using the PSS scale produced similar results. PSS, but not USQ, interacted with time to predict pain (time², p = .048; time³, p = .024). Relationships held even after adjusting for covariates, such as depression. Future research should determine if differential responses to exercise by stress have implications for behavioral interventions and mental health outcomes.     

The impact of exercise environments on adolescents’ cognitive and psychological outcomes: A randomised controlled trial

Exercise in natural environments can improve cognition, positive affect, and reduce psychological stress. However, it remains unclear whether these benefits are subject to a gradient effect, whereby more natural features confer greater cognitive and psychological benefits. This study examined the influence of the exercise environment (i.e., the degree of nature) on cognition, and psychological outcomes in a sample of adolescents (n = 90; mean age = 14.3 ±.05 years). Four groups were randomised to one of the following experimental conditions: a non-exercise indoor control, indoor exercise, park exercise, and exercise in a nature reserve. Participants’ self-reported their stress, affect, and vitality and completed two measures of cognition (‘Rapid Visual Information Processing’ and ‘Spatial Working Memory’) immediately before and ~6 min after exercise. All exercise conditions participated in a group-based circuit lasting ~20 min, which included a mixture of aerobic and body-weight resistance activities. Linear mixed models were used to examine changes within and between groups. The indoor group increased sustained attention accuracy compared to the park group. There were no between-group differences in working memory. The indoor and nature groups increased cognitive arousal compared to control. The park group improved in state-level vitality compared to control. The mixed-results of this research do not support our ‘nature gradient’ hypothesis, whereby cognitive and psychological outcomes would improve in accordance with the degree of nature present in the exercise environment.     

Executive function during and after acute moderate aerobic exercise in adolescents

ObjectivesIn two experiments, we investigated the effects of acute moderate-intensity exercise on aspects of executive function in adolescents.DesignAn experimental design was used.MethodsFifty-five Japanese adolescents (Experiment 1: N = 28; Experiment 2: N = 27) performed a modified flanker task and a modified n-back task to assess inhibitory control and working memory before, during, and after walking on a treadmill at moderate intensity (Experiment 1: 60% maximal heart rate; Experiment 2: 70% maximal heart rate). In a separate session, the same testing sequence was administered while participants sat in a chair.ResultThe results revealed that reaction time for working memory increased during exercise in both experiments, while response accuracy decreased during exercise only at 70% maximal heart rate. Moderate intensity exercise had no substantial effect on inhibition control. Following cessation of the exercise, no effects were observed for either executive function assessment.ConclusionThese results indicate that moderate intensity exercise selectively affects executive function in adolescents. Further, during physical activity, adolescents maintain inhibitory control, but their working memory declines. Further research is required to reveal the mechanisms underlying this phenomenon and to expand beyond the laboratory setting to the areas of sports and physical activities of daily living.