scholarly journals Chewing and Cognitive Improvement: The Side Matters

2021 ◽  
Vol 15 ◽  
Author(s):  
Maria Paola Tramonti Fantozzi ◽  
Vincenzo De Cicco ◽  
Davide De Cicco ◽  
Paola d’Ascanio ◽  
Enrico Cataldo ◽  
...  
Keyword(s):  
Cognitive Performance ◽  
Pupil Size ◽  
Simultaneous Increase ◽  
Emg Activity ◽  
Simultaneous Presence ◽  
Cognitive Improvement ◽  
Trigeminal Stimulation ◽  
Ascending Reticular Activating System ◽  
Before And After ◽  
Reticular Activating System

Chewing improves cognitive performance, which is impaired in subjects showing an asymmetry in electromyographic (EMG) masseter activity during clenching. In these subjects, the simultaneous presence of an asymmetry in pupil size (anisocoria) at rest indicates an imbalance in Ascending Reticular Activating System (ARAS) influencing arousal and pupil size. The aim of the present study was to verify whether a trigeminal EMG asymmetry may bias the stimulating effect of chewing on cognition. Cognitive performance and pupil size at rest were recorded before and after 1 min of unilateral chewing in 20 subjects with anisocoria, showing an EMG asymmetry during clenching. Unilateral chewing stimulated performance mainly when it occurred on the side of lower EMG activity (and smaller pupil size). Following chewing on the hypotonic side, changes in cognitive performance were negatively and positively correlated with those in anisocoria and pupil size, respectively. We propose that, following chewing on the hypotonic side, the arousing effects of trigeminal stimulation on performance are enhanced by a rebalancing of ARAS structures. At variance, following chewing on the hypertonic side, the arousing effect of trigeminal stimulation could be partially or completely prevented by the simultaneous increase in ARAS imbalance.

scholarly journals The Relationship Between Cognitive Performance and Cardiorespiratory Fitness in Adolescents

2021 ◽  
Vol 1 (120) ◽  
pp. 56-60
Author(s):  
Justė Knatauskaitė ◽  
Kazimieras Pukėnas ◽  
Tomas Kentra
Keyword(s):  
Cognitive Performance ◽  
Cardiorespiratory Fitness ◽  
Repeated Measures ◽  
Exercise Intervention ◽  
Control Group ◽  
Cognitive Improvement ◽  
Before And After ◽  
Group 2 ◽  
The Relationship ◽  
Experimental Group

Background. Literature suggests cardiorespiratory fitness as a factor influencing cognitive improvement. The authors of the present study sought to investigate if cardiorespiratory fitness related to cognitive performance after an acute bout of game-based exercise of different intensities in adolescents. Methods.  As many as 37 adolescents (24 girls and 13 boys, 15–16 years of age) were assigned to three groups: experimental group 1 (EX 1), experimental group 2 (EX 2), and control (CON) group. The experimental groups experienced different levels of exercise intensity (EX 1 – light intensity, EX 2 – vigorous intensity). The Shuttle Run Test was performed a week before the intervention and VO2peak was calculated. Symbol Digit Modalities Test (SDMT) was evaluated before and after the acute intervention. A 2 x 3 repeated-measures ANOVA was used to analyze the SDMT and Pearson’s correlation coefficient was used to estimate the relationship between the cognitive performance (SDMT) and cardiorespiratory fitness (VO2peak). Results. Comparing the SDMT scores before and after the intervention, there were no differences found between the three groups. Neither in any of the experimental groups nor in the control group was a relationship between the SDMT score and VO2peak observed. Conclusion. Acute game-based exercise intervention did not prove to improve cognitive performance effectively. The authors of the present paper did not confirm the relationship between cardiorespiratory fitness and cognitive performance in adolescents. Keywords: exercise, cognitive performance, cardiorespiratory fitness.

scholarly journals Coupling between Trigeminal-Induced Asymmetries in Locus Coeruleus Activity and Cognitive Performance

Symmetry ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1676
Author(s):  
Maria Paola Tramonti Tramonti Fantozzi ◽  
Ottavia Marconi ◽  
Federica Simoni ◽  
Vincenzo De De Cicco ◽  
Davide De De Cicco ◽  
...  
Keyword(s):  
Locus Coeruleus ◽  
Cognitive Performance ◽  
Pupil Size ◽  
Cortical Excitability ◽  
Emg Activity ◽  
Performance Task ◽  
The Asymmetry ◽  
Spontaneous Fluctuations ◽  
Size Asymmetry ◽  
Average Pupil

In humans, the asymmetry in the masseter electromyographic (EMG) activity during clenching is positively correlated with the degree of pupil size asymmetry (anisocoria) at rest. Anisocoria reveals an asymmetry in LC activity, which may lead to an imbalance in cortical excitability, detrimental to performance. Hereby, we investigated, in individual subjects, the possibility that occlusal correction, which decreases EMG asymmetry, improves performance by balancing LC activity. Cognitive performance, task-related mydriasis, and pupil size at rest were modified by changing the occlusal condition. Occlusal-related changes in performance and mydriasis were negatively correlated with anisocoria changes in only 12/20 subjects. Within this population, spontaneous fluctuations in mydriasis and anisocoria also appeared negatively coupled. Occlusal-related changes in performance and mydriasis were negatively correlated with those in average pupil size (a proxy of average LC activity) in 19/20 subjects. The strongest association was observed for the pupil changes occurring on the side with higher EMG activity during clenching. These findings indicate that the effects of occlusal conditions on cognitive performance were coupled to changes in the asymmetry of LC activity in about half of the subjects, while they were related to changes in the average tonic LC activity in virtually all of them.

Cognitive functioning in patients with nonfunctioning pituitary adenoma before and after endoscopic endonasal transsphenoidal surgery

2020 ◽  
Vol 133 (3) ◽  
pp. 709-716
Author(s):  
Elke Butterbrod ◽  
Karin Gehring ◽  
Eduard H. Voormolen ◽  
Paul R. A. M. Depauw ◽  
Willy-Anne Nieuwlaat ◽  
...  
Keyword(s):  
Cognitive Functioning ◽  
Cognitive Performance ◽  
Transsphenoidal Surgery ◽  
Cognitive Status ◽  
Control Group ◽  
Endoscopic Endonasal ◽  
Cognitive Domains ◽  
Cognitive Improvement ◽  
Before And After ◽  
Endoscopic Endonasal Transsphenoidal Surgery

OBJECTIVEPatients with nonfunctioning pituitary adenomas (NFPAs) can suffer from cognitive dysfunction. However, the literature on longitudinal cognitive follow-up of patients undergoing endoscopic endonasal transsphenoidal surgery (EETS) is limited. This study was performed to investigate perioperative cognitive status and course in patients with NFPAs.METHODSPatients underwent computerized neuropsychological assessment 1 day before (n = 45) and 3 months after (n = 36) EETS. Performance in 7 domains was measured with a computerized test battery (CNS Vital Signs) and standardized using data from a healthy control group. The authors conducted analyses of cognitive performance at both time points and changes pre- to post-ETSS on a group and an individual level. Linear multiple regression analyses were employed to investigate predictors of cognitive performance.RESULTSOn average, patients scored significantly lower in 6 of 7 cognitive domains before and after surgery than controls. Impairment proportions were significantly higher among patients (56% before surgery, 63% after surgery) than among controls. Patients showed no change over time in group-level (mean) performance, but 28% of individual patients exhibited cognitive improvement and 28% exhibited cognitive decline after surgery. Hormonal deficiency showed a positive correlation with verbal memory before surgery. Postoperative performances in all cognitive domains were predicted by preoperative performances.CONCLUSIONSCognitive impairment was present before and after EETS in over half of NFPA patients. Individual patients showed diverse postoperative cognitive courses. Monitoring of cognitive functioning in clinical trajectories and further identification of disease-related and psychological predictors of cognition are warranted.

THE POSSIBILITY OF LINKING SPONTANEOUS AND INDUCED NEUROCOGNITIVE PLASTICITY: CAN COGNITIVE TRAINING INFLUENCE COMPENSATORY BRAIN ACTIVITY IN OLDER ADULTS? THEORETICAL AND EMPIRICAL PREMISES

2020 ◽  
Vol 18 (4) ◽  
pp. 507-523
Author(s):  
Ludmiła Zając-Lamparska
Keyword(s):  
Older Adults ◽  
Young Adults ◽  
Cognitive Performance ◽  
Cognitive Training ◽  
Study Design ◽  
Successful Aging ◽  
Reference Group ◽  
Brain Activity ◽  
Before And After ◽  
Theory Of Aging

One of the most important determinants of successful aging is cognitive ability. Although cognitive decline is a well-documented phenomenon characteristic of aging, it is acknowledged that aging can also be related to cognitive neuroplasticity that allows one to compensate the decline and adapt to it. Cognitive neuroplasticity may be spontaneous or induced by external influences. An example of the former is compensatory brain activity in older adults, and the latter – improvement in cognitive functioning under the influence of cognitive training. Both the compensatory brain activity of older adults and the effectiveness of cognitive training in this age group have already been extensively studied. However, it has not yet been examined whether they can be linked. The article indicates theoretical and empirical premises for the possibility of influencing compensatory brain activity in older adults by cognitive training. In the most comprehensive way the phenomenon of compensatory brain activity in older adults is addressed by the STAC model – the Scaffolding Theory of Aging and Cognition, which also provides the theoretical grounds for the possible impact of cognitive training on compensatory brain activity. There are also empirical arguments in favour of such an impact, but they are quite limited in nature. The reason for this is the lack of research directly addressing the problem of the consistency of brain activity changes resulting from cognitive training with the assumptions of compensatory brain activity models, such as STAC. The theoretical grounds for the linkage of compensatory brain activity in older adults with the influence of cognitive training are clear. However, the analysis of the studies discussed in the article suggests that failing to embed the study design within the theoretical framework of compensatory brain activity in older adults may lead to the exclusion of factors important in drawing conclusions about this phenomenon. The following elements of the study design were identified as necessary to include: participation of young adults in the study as a reference group, usage of tasks in different difficulty levels during the measurement of brain activity and consideration of the relation between brain activity and cognitive performance, and comparison of brain activity in relation to cognitive performance before and after training in both, older and young adults.

Wipe and flexion reflexes of the frog. II. Response to perturbations

1993 ◽  
Vol 69 (5) ◽  
pp. 1736-1748 ◽  
Author(s):  
J. L. Schotland ◽  
W. Z. Rymer
Keyword(s):  
External Load ◽  
Hind Limb ◽  
Joint Angle ◽  
Activity Level ◽  
Temporal Organization ◽  
Emg Activity ◽  
Relative Timing ◽  
Before And After ◽  
Movement Segment ◽  
Initial Movement

1. To evaluate the hypothesis that the neural control of sensorimotor transformations may be simplified by using a single control variable, we compared the movement kinematics and muscle activity patterns [electromyograms (EMGs)] of the frog during flexion withdrawal and the hind limb-hind limb wipe reflex before and after adding an external load. In addition, the flexibility of spinal cord circuitry underlying the hind limb-hind limb wipe reflex was evaluated by comparing wipes before and after removal of one of the contributing muscles by cutting a muscle nerve. 2. The kinematics of the movements were recorded using a WATSMART infrared emitter-detector system and quantified using principal-components analysis to provide a measure of the shape (eigenvalues) and orientation (eigenvector coefficients) of the movement trajectories. The neural pattern coordinating the movements was characterized by the latencies and magnitudes of EMGs of seven muscles acting at the hip, knee, and ankle. These variables were compared 1) during flexion withdrawal and the initial movement segment of the limb during the hind limb-hind limb wipe reflex in both unrestrained movements and in movements executed when a load equal to approximately 10% of the animal's body weight was attached to a distal limb segment and 2) during the initial movement segment of the wipe reflex before and after cutting the nerve to the knee flexor-hip extensor, iliofibularis. 3. Addition of the load had no discernible effect on the end-point position of the foot during either reflex. However, during the loaded flexion reflex, the ankle joint did not move until after the hip and knee joints had moved to their normal positions. This delayed flexion of the ankle was accompanied by large increases in the magnitude of EMG activity in two ankle muscles that exceeded the levels found during unrestrained movements. Significant changes in the temporal organization of the EMG pattern accompanied the change in joint angle relations during flexion withdrawal. 4. Despite the addition of an external load, all animals successfully and reliably removed the stimulus during the wipe reflex, and the relative timing of both the EMG pattern and joint angle motion was preserved. 5. Immediately after section of the nerve to a single muscle (iliofibularis), all animals successfully and reliably removed the stimulus during the wipe reflex. The relative timing of muscle activation was preserved, accompanied by a reduction in the activity level of gluteus magnus, a muscle with action reciprocal to iliofibularis.(ABSTRACT TRUNCATED AT 400 WORDS)

EMG Changes in Human Thenar Motor Units With Force Potentiation and Fatigue

2006 ◽  
Vol 95 (3) ◽  
pp. 1518-1526 ◽  
Author(s):  
C. K. Thomas ◽  
R. S. Johansson ◽  
B. Bigland-Ritchie
Keyword(s):  
Motor Unit ◽  
Motor Units ◽  
Emg Activity ◽  
Single Motor Unit ◽  
Tetanic Force ◽  
Twitch Force ◽  
Emg Amplitude ◽  
Before And After ◽  
Induced Changes ◽  
Motor Unit Emg

Few studies have analyzed activity-induced changes in EMG activity in individual human motor units. We studied the changes in human thenar motor unit EMG that accompany the potentiation of twitch force and fatigue of tetanic force. Single motor unit EMG and force were recorded in healthy subjects in response to selective stimulation of their motor axons within the median nerve just above the elbow. Twitches were recorded before and after a series of pulse trains delivered at frequencies that varied between 5 and 100 Hz. This stimulation induced significant increases in EMG amplitude, duration, and area. However, in relative terms, all of these EMG changes were substantially smaller than the potentiation of twitch force. Another 2 min of stimulation (13 pulses at 40 Hz each second) induced additional potentiation of EMG amplitude, duration, and area, but the tetanic force from every unit declined. Thus activity-induced changes in human thenar motor unit EMG do not indicate the alterations in force or vice versa. These data suggest that different processes underlie the changes in EMG and force that occur during human thenar motor unit activity.

Tubular Daylighting Devices and People: A comparison of the human responses to Tubular Daylighting Devices and fluorescent lighting

2021 ◽  
Author(s):  
◽  
James Sullivan
Keyword(s):  
Cognitive Performance ◽  
Well Being ◽  
Performance Change ◽  
Performance Effects ◽  
Before And After ◽  
And Performance ◽  
The University ◽  
Fluorescent Lighting ◽  
Larger Sample ◽  
Before And After Study

<p>Tubular Daylighting Devices are used to bring daylight into deep-plan spaces, and meet sustainability goals. However, they are expensive, and justification for their use lies in hypothesised benefits they can provide in areas such as well-being and productivity. Yet, there is very little research into the effects of Tubular Daylighting Devices. The broader daylighting literature suggests that benefits to satisfaction, mood, and performance are possible — though research into the benefits of daylight is still not conclusive.  Therefore, a before and after study was carried out in a windowless computer room in the university to compare how the students responded under TDDs versus typical electric lighting. Their cognitive performance, change in mood, average sleepiness, and perceptions of the room and lighting were measured.  TDDs significantly increased ratings of room attractiveness and brightness, and had no more perceived glare than the electric lighting. Ratings of lighting quality were on a par with both typical electric lighting and good modern lighting. They were also just as effective on overcast days as sunny. No effects were found on performance or sleepiness, and mood results were inconclusive.  Overall, it is suggested that TDDs can be considered to be on a par with good modern lighting, and superior to typical existing lighting. Note, however, that it is possible that effects in rooms with windows could differ from those found here. Further research should use longer exposures and larger sample sizes if they wish to find performance effects.</p>

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