Effect of acute moderate exercise on cognitive event-related potentials n100, p200, n200, and interpeak latencies

Comparison of P300 Cognitive-evoked Potentials and Visual and Auditory Reaction Time in Stage 5 Chronic Kidney Disease Patients on Different Treatment Modalities

Patients with chronic kidney disease (CKD) are at a higher risk of cognitive impairment. Poor quality of life and decreased compliance are frequently observed with cognitive decline among CKD patients. Cognitive impairment among Stage 5 CKD patients varies with different modalities of treatment, and contradicting results have been reported. Fifty-four medically stable Stage 5 CKD patients undergoing different modalities of treatment were recruited: Patients with Stage 5 CKD on maintenance hemodialysis (HD) (n = 18), continuous ambulatory peritoneal dialysis (CAPD) (n = 18), and conservative management (CM) (n = 18). Eighteen apparently healthy participants were recruited as a control group. The cognitive functions assessed were P300 event- related potential, auditory and visual reaction times (VRTs). Kidney function was assessed by serum creatinine and estimated glomerular filtration rate. Creatinine levels were significantly higher in all three treatment groups compared with the control group. Multivariate analysis revealed a significant association between the CKD groups (n = 54) and the parameters of cognitive function. P300 latency was prolonged in all treatment groups compared with the control group and was significantly prolonged in patients on CM compared with HD and CAPD patients. The VRT of CM patients was found to be significantly higher compared with the control group. The auditory reaction time was significantly prolonged in all treatment groups compared with the control group and in the CM group compared with the CAPD group. Cognitive function was more affected in Stage 5 CKD patients on CM compared with patients undergoing HD or CAPD.

Link of neurocognitive deficit to impaired cardiovagal modulation in prehypertensives is comparable to newly diagnosed hypertensives in young Indian population

BACKGROUND

Hypertension has been reported to cause impaired cardiovagal modulation and a wide variety of cognitive loss. However, the link cardiovagal modulation to neurocognitive impairment has not been studied yet. The present study has compared the link cardiovagal modulation to neurocognitive impairment between prehypertension and newly diagnosed hypertension in young adults.

METHODS

One hundred forty-seven subjects (42 normotensives, 54 prehypertensives and 51 newly diagnosed hypertensives) aged between 18-44 years were included in this case-control study. The demographic, anthropometric, basal parameters, heart rate variability (HRV), cardiovascular autonomic function tests (CAFTs), event-related potential P300 and biochemical parameters were recorded in all the groups. Association of various parameters with neurocognitive deficit was studied by Pearson correlation analysis and independent contribution of various factors to cognitive deficit was assessed by multiple regression analysis in the study groups.

RESULTS

Total power (TP) of HRV, the marker of cardiovagal modulation was reduced in both prehypertensives and hypertensives compared to controls. Among CAFTs, the ΔDBP_IHG was increased, and 30:15 ratio and E:I ratio were decreased in both study groups. The latency of P300 (the marker of neurocognition) was significantly prolonged in prehypertensives and hypertensives and P300 latency was significantly associated with reduction in TP in both the groups. HOMA-IR was increased, and total oxidant capacity was decreased in prehypertensives and hypertensives, and both these parameters had independent contribution to P300.

CONCLUSION

Prehypertensives had considerable autonomic imbalance, reduced cardiovagal modulation and neurocognitive deficit that were comparable to newly diagnosed hypertensives. Though the causal relationship between cardiovagal modulation and neurocognitive impairment can't be established from the findings of the present study, it appears that neurocognitive deficit might have some possible link to the decreased cardiovagal modulation and metabolic derangements in young prehypertensives and hypertensives.

Association of Circulating Brain-Derived Neurotrophic Factor with Cognition among Adult Obese Population

Background

Obesity has a strong association with the risk of developing cognitive impairment and dementia at a later age. Brain-derived neurotrophic factor (BDNF) and its receptor appear to be important components in cognitive function and are also involved in energy homeostasis. The level of circulating BDNF and its association with cognition has yet to be delineated clearly. In this work we studied the association of circulating BDNF with cognition among the adult obese population.

Methods

The study involved 132 healthy participants between 18 and 40 years of age and of both sexes. The participants were categorized into an obesity group (n=66) and a non-obese group (n=66) based on their body mass index (Asian criteria). The level of cognitive performance was assessed by the event-related potentials P300 (ERPs-P300), mini-mental state examination (MMSE), both visual and auditory reaction times (VRT and ART, respectively), and other pen and paper tests related to memory and executive function. Serum BDNF, glycemic and lipid profiles were estimated.

Results

We found significant differences in the ERPs-P300 latency (P<0.001) and amplitude (P=0.002) between the non-obese and obese group. The MMSE score was significantly reduced while VRT (P=0.005) and ART (P=0.001) were larger in the obese group. BDNF levels (P<0.001) were significantly reduced and negatively associated with the obese group. ERPs-P300 latency was negatively associated (r=–0.674, P=0.001) whereas amplitude (r=0.507, P<0.001) was positively associated with the BDNF levels in the adult obese population.

Conclusion

We found reduced circulating BDNF levels in obese adults and that lower BDNF levels were strongly associated with cognitive decline in the obese adult population.

Effects of Acute Visual Stimulation Exercise on Attention Processes: An ERP Study

BACKGROUNDS

It remains to be determined whether visual stimuli during exercise differentially influence the attention process. The purpose of the present study was to examine if different color stimuli during aerobic exercise are associated with different attention processes.

METHODS

22 college students completed a four 30-min running session during the presentation of different color stimuli (blue, green, red, and yellow) and without color stimulus on separate visits. The Kanizsa triangle task was administrated before and immediately after exercise to assess the attention process. Behavioral performance (accuracy and response time (RT)) and event-related potential (P2, N2b and P3a) were recorded during the test.

RESULTS

Valid/invalid cue RT during the Kaniza test performance was significantly faster following the presentation of color stimuli during treadmill exercise compared to the seated rest. During exercise, these changes were larger after green and yellow stimuli than red in invalid cue RT. P2, N2b and P3a amplitudes of green were significantly larger than the other colors for both valid and invalid cues. Red color showed the lowest P2 and P3a amplitudes for both valid and invalid cues among colors.

CONCLUSION

The distinctive neurocognitive changes during aerobic exercise suggest different effects of color stimuli on visual search attention, attention capture, attentional orienting and processing speed. This study will be a first step to understand the optimal environmental setting during exercise for subsequent improvements in the attention process.

Constitutive and Stress-Induced Psychomotor Cortical Responses to Compound K Supplementation

Isolated ginsenoside metabolites such as Compound K (CK) are of increasing interest to consumer and clinical populations as safe and non-pharmacological means to enhance psychomotor performance constitutively and in response to physical or cognitive stress. Nevertheless, the influence of CK on behavioral performance and EEG measures of cortical activity in humans is undetermined. In this double-blinded, placebo-controlled, counterbalanced within-group study, dose-dependent responses to CK (placebo, 160 and 960 mg) were assessed after 2 weeks of supplementation in nineteen healthy men and women (age: 39.9 ± 7.9 year, height 170.2 ± 8.6 cm, weight 79.7 ± 11.9 kg). Performance on upper- and lower-body choice reaction tests (CRTs) was tested before and after intense lower-body anaerobic exercise. Treatment- and stress-related changes in brain activity were measured with high-density EEG based on event-related potentials, oscillations, and source activity. Upper- (−12.3 ± 3.5 ms, p = 0.002) and lower-body (−12.3 ± 4.9 ms, p = 0.021) response times improved after exercise, with no difference between treatments (upper: p = 0.354; lower: p = 0.926). Analysis of cortical activity in sensor and source space revealed global increases in cortical arousal after exercise. CK increased activity in cortical regions responsible for sustained attention and mitigated exercise-induced increases in arousal. Responses to exercise varied depending on task, but CK appeared to reduce sensory interference from lower-body exercise during an upper-body CRT and improve the general maintenance of task-relevant sensory processes.

Comparison of cognitive auditory event related potentials and executive functions in adolescent athletes and non-athletes - A cross sectional study

There is strong evidence for the positive physical health outcomes of physical conditioning (athletic training. But there is a dearth of data on the impact of exercise on cognition, particularly in the adolescent age group. Further, most of the studies done on this topic are mainly acute in nature, and few that have seen long term effect of exercise have very rarely used objective measures such as event-related potentials. Hence, the present study was conceived to compare cognition in athletes (individual who have undergone long term physical activity) and non-athletes. We designed a cross-sectional comparative study involving apparently healthy volunteer boys in the age group of 10-19 years-non-athletes (n = 30) and athletes (n = 30). Paper pencil tests such as letter cancellation test, auditory and visual recognition reaction time, trail making test (A and B) were recorded along with auditory event-related potentials (N100, P200, N200, and P300). Data were analyzed using an unpaired t-test and Mann-Whitney U test according to the data distribution. Athletes completed letter cancellation task and trail making test faster than non-athletes. Athletes visual and auditory reaction time were lesser. Athletes had reduced latency and higher amplitude of auditory event-related potentials (N100, P200, N200, and P300) as compared to non-athletes. Hence, we conclude that athletic level physical training has a beneficial role in the executive cognitive domain among adolescents.

Acute Moderate-Intensity Exercise Generally Enhances Attentional Resources Related to Perceptual Processing

The present study aimed to investigate whether acute moderate-intensity exercise led to a selective effect on executive function tasks or general effect on cognitive tasks that involve executive function and basic information processing in young adults. Besides, we also aimed to examine acute exercise's effect on multiple ERP components (e.g., P2, N2, P3b, and N450) to expand previous research. Seventy-two young adults were randomly assigned to the exercise or control groups. The Stroop task was administrated before and after treatments (exercise or reading), and the P2, N2, P3b, and N450 components of the Event-Related Potential (ERP) waveform were recorded and analyzed. Larger P2 amplitudes on both congruent and incongruent tasks were observed following acute exercise. Acute exercise did not influence accuracy or response time, and no effects on N2, P3b, and N450 components were found. These findings suggest that acute moderate-intensity exercise may have a generally beneficial effect on mobilization of attentional resources related to perceptual processing and exercise-related physiological arousal.

Physical Exhaustion Induced Variations in Event-Related Potentials and Cognitive Task Performance in Young Adults

Background/Aims

Physical exhaustion is not always peripheral, and it is the brain that causes the sensation of fatigue either due to decrease of metabolic resources or due to central activation process that regulates attention and performance. This study was undertaken to observe the variations in event-related potentials (ERPs) and cognitive performance after an exhausting physical exercise.

Methods

A total of 60 healthy young adult subjects were included in the study. The study was conducted in 2 phases with at least a week gap between the phases. The participants answered a Multidimensional Fatigue Inventory (MFI-20) questionnaire before and after trials in each phase to measure the induced physical exhaustion. In phase I (control trial), the ERP data were processed using P300, Standard auditory "oddball paradigm," on computerized evoked potential recorder (RMS EMG MK-2) using 10/20 system to know the engagement of attention after which participants were given to perform cognitive tasks such as "Stroop Test, Trial Making Test and Mini Mental State Examination." In Phase II (exercise trial), the participants were instructed to cycle as hard as they could, till they could not continue anymore, which was followed by recording of P300-evoked potentials and performance of cognitive tasks as in Phase I. Paired t test was used to compare between any dependent variables.

Results

Fatigue-related subjective measures (MFI-20) showed that both mental and physical exhaustion were significantly greater in the exercise-involved cognitive trial than in the control trial. Lower P300 latencies reflect faster reaction time; however, their response accuracies were poorer resulting in poorer cognitive performances. Participants subjected to control trial performed better in terms of higher percentage accuracy but with slow reaction time.

Conclusion

The participants experienced more fatigue physically and mentally during the exercise that involved cognitive tasks. An apparent decrease in attention based on decreased percentage accuracy of response was evident, implying that fatigue, performance, and attention are interdependent.

Association of Sympathovagal Imbalance With Cognitive Impairment in Type 2 Diabetes in Adults

OBJECTIVE

Sympathovagal imbalance (SVI) has been reported to be associated with metabolic derangements in type 2 diabetes. We investigated the association of SVI with cognitive impairment in patients with type 2 diabetes.

METHODS

Patients with a new diagnosis of type 2 diabetes (n=43) and age-matched healthy control subjects (n=43) were recruited for the study. Body mass index and blood pressure measurements were recorded. SVI was assessed by spectral analysis of heart rate variability (HRV), and cognitive function was assessed by recording the positive wave that appears in 300 milliseconds from application of stimulus in event-related potential tracing (P300). Insulin resistance was determined by the homeostatic model assessment of insulin resistance (HOMA-IR) formula using blood glucose and insulin data, and oxidative stress was assessed by estimation of malondialdehyde. Association of various factors with cognitive impairment was evaluated by Pearson correlation analysis, and independent contributions of these factors to cognitive impairment were assessed by multiple regression analysis.

RESULTS

P300 latency was significantly prolonged in the diabetes group compared with the control group. Ratio of low-frequency to high-frequency power (LF-HF ratio) of HRV, the marker of SVI was found to be significantly correlated and linked with P300. Malondialdehyde and HOMA-IR were correlated with LF-HF ratio.

CONCLUSION

Treatment-naïve patients with type 2 diabetes have SVI and considerable cognitive impairment. Insulin resistance and oxidative stress contribute to cognitive impairment, and SVI could be the physiologic link to cognitive impairment in treatment-naïve patients with type 2 diabetes.

Neuroelectric adaptations to cognitive processing in virtual environments: an exercise-related approach

Recently, virtual environments (VEs) are suggested to encourage users to exercise regularly. The benefits of chronic exercise on cognitive performance are well documented in non-VE neurophysiological and behavioural studies. Based on event-related potentials (ERP) such as the N200 and P300, cognitive processing may be interpreted on a neuronal level. However, exercise-related neuroelectric adaptation in VE remains widely unclear and thus characterizes the primary aim of the present study. Twenty-two healthy participants performed active (moderate cycling exercise) and passive (no exercise) sessions in three VEs (control, front, surround), each generating a different sense of presence. Within sessions, conditions were randomly assigned, each lasting 5 min and including a choice reaction-time task to assess cognitive performance. According to the international 10:20 system, EEG with real-time triggered stimulus onset was recorded, and peaks of N200 and P300 components (amplitude, latency) were exported for analysis. Heart rate was recorded, and sense of presence assessed prior to and following each session and condition. Results revealed an increase in ERP amplitudes (N200: p < 0.001; P300: p < 0.001) and latencies (N200: p < 0.001) that were most pronounced over fronto-central and occipital electrode sites relative to an increased sense of presence (p < 0.001); however, ERP were not modulated by exercise (each p > 0.05). Hypothesized to mirror cognitive processing, decreases of cognitive performance's accuracy and reaction time failed significance. With respect to previous research, the present neuroelectric adaptation gives reason to believe in compensative neuronal resources that balance demanding cognitive processing in VE to avoid behavioural inefficiency.