Relative Power Spectrum Research Articles

A study comparing brain wave patterns of fentanyl and ketamine in adult patients undergoing minimally invasive surgery.

This study aimed to investigate and compare the neurophysiological impacts of two widely used anesthetic agents, Fentanyl and Ketamine, on EEG power spectra during different stages of anesthesia in adult patients undergoing minimally invasive surgery. EEG data were collected from patients undergoing anesthesia with either Fentanyl or Ketamine. The data were analyzed for relative power spectrum and fast-to-slow wave power ratios, alongside Spectral Edge Frequency 95% (SEF95), at 3 key stages: pre-anesthesia, during stable anesthesia, and post-anesthesia. EEG Relative Power Spectrum: Initially, both groups exhibited similar EEG spectral profiles, establishing a uniform baseline (P > .05). Upon anesthesia induction, the Fentanyl group showed a substantial increase in delta band power (P < .05), suggesting deeper anesthesia, while the Ketamine group maintained higher alpha and beta band activity (P < .05), indicative of a lighter sedative effect. Fast and Slow Wave Power Ratios: The Fentanyl group exhibited a marked reduction in the fast-to-slow wave power ratio during anesthesia (P < .05), persisting post-anesthesia (P < .05) and indicating a lingering effect on brain activity. Conversely, the Ketamine group demonstrated a more stable ratio (P > .05), conducive to settings requiring rapid cognitive recovery. Spectral Edge Frequency 95% (SEF95): Analysis showed a significant decrease in SEF95 values for the Fentanyl group during anesthesia (P < .05), reflecting a shift towards lower frequency power. The Ketamine group experienced a less pronounced decrease (P > .05), maintaining a higher SEF95 value that suggested a lighter level of sedation. The study highlighted the distinct impacts of Fentanyl and Ketamine on EEG power spectra, with Fentanyl inducing deeper anesthesia as evidenced by shifts towards lower frequency activity and a significant decrease in SEF95 values. In contrast, Ketamine's preservation of higher frequency activity and more stable SEF95 values suggests a lighter, more dissociative anesthetic state. These findings emphasize the importance of EEG monitoring in anesthesia for tailoring anesthetic protocols to individual patient needs and optimizing postoperative outcomes.

Predictive modeling based on functional connectivity of interictal scalp EEG for infantile epileptic spasms syndrome

ObjectiveThis study aims to delineate the electrophysiological variances between patients with infantile epileptic spasms syndrome (IESS) and healthy controls and to devise a predictive model for long-term seizure outcomes. MethodsThe cohort consisted of 30 individuals in the seizure-free group, 23 in the seizure-residual group, and 20 in the control group. We conducted a comprehensive analysis of pretreatment electroencephalography, including the relative power spectrum (rPS), weighted phase-lag index (wPLI), and network metrics. Follow-up EEGs at 2 years of age were also analyzed to elucidate physiological changes among groups. ResultsInfants in the seizure-residual group exhibited increased rPS in theta and alpha bands at IESS onset compared to the other groups (all p < 0.0001). The control group showed higher rPS in fast frequency bands, indicating potentially enhanced cognitive function. The seizure-free group presented increased wPLI across all frequency bands (all p < 0.0001). Our predictive model utilizing wPLI anticipated long-term outcomes at IESS onset (area under the curve 0.75). ConclusionOur findings demonstrated an initial “hypersynchronous state” in the seizure-free group, which was ameliorated following successful treatment. SignificanceThis study provides a predictive model utilizing functional connectivity and insights into the diverse electrophysiology observed among outcome groups of IESS.

Influence of tissue-electrode distance on unipolar and bipolar voltage for large-tip, ring-, and mini-electrodes

Abstract Background The characteristics of intracardiac unipolar and bipolar voltage electrograms (EGM) acquired by electrophysiological catheters depend on the electrical source and on the electrode design and configuration. Purpose The aim of the study was to assess the impact of the electrode configuration and their distance from the myocardial tissue (electric source) on the unipolar and bipolar intracardiac electrograms recorded with a multi-electrode focal ablation catheter. Methods We retrospectively analyzed left atrial 3D electroanantomical maps (EAMs) of 25 patients performed in sinus rhythm using the IntellaNav Mifi OI catheter (Boston Scientific, USA) with a 4.5 mm tip-electrode, three mini-electrodes and three 2 mm ring electrodes. The unipolar and bipolar EGMs were characterized based on the peak-to-peak amplitude (amp), the signal duration (width), the maximal slope, and the relative high power spectrum (HF_rel) as ratio of the power spectrum of frequencies above and below 50Hz. Distances of the electrode from the tissue were calculated from the electroanatomic reconstruction. Except for the HF_rel with absolute values are reported, all characteristics are normalized using the tip-electrode for unipolar or tip-to-ring electrode values for bipolar measures. EGMs with bipolar voltage amplitude of &amp;gt;0.5 mV were included to focus on healthy tissue. Results We analyzed the EGMs of 5183 catheter positions with horizontal to perpendicular orientation. From horizontal catheter orientation with a similar distance from the tissue for all electrodes, the unipolar EGM of the ring electrodes showed an increased amplitude (140%), slope (150%) and HF_rel (16% vs 11%) compared to the tip- and mini-electrodes. For bipolar EGM, however, the tip- ring pair showed the largest amplitude, width, and slope. The HF_rel was larger for the ring electrode pairs compared to the tip-ring electrode (58% to 39%). The median amplitude (amp), slope, and HF_rel for the ring electrodes showed a strong power-law decay function with distance, whereas the width increases linearly with distance from the surface (Figure, blue dotted lines). The intersection (red circle) of the steep linear decline at close distance to the tissue (reflecting a strong influence on the EGM) with the flat line at larger distances (dash-dotted lines) was considered as nearfield boundary. A HF_rel cutoff of &amp;gt;10% for unipolar (Figure, red arrow) and &amp;gt;30% for bipolar EGMs might be used to identify this boundary. Conclusion We confirmed a higher amplitude for small ring-electrodes compared to larger tip electrodes in unipolar amplitude but not for bipolar electrograms. Furthermore, a strong decay of the amplitude, slope and HF_rel with distance could be observed. The decay functions are suggestive for a nearfield boundary distance below 4mm from the tissue. Further studies are warranted to confirm this observation.Summary of characteristics over distance

Assessing the Anxiolytic and Relaxation Effects of Cinnamomum camphora Essential Oil in University Students: A Comparative Study of EEG, Physiological Measures, and Psychological Responses.

Cinnamomum camphora is a commercially important tree species in China, and it's also a common native tree in the forests of southern China. However, literature on the impact of Cinnamomum camphora essential oil (CCEO) on human psychophysiological activity is scarce. Hence, the primary objective of this study was to examine the effect of exposure to CCEO on the functioning of the human autonomic nervous system, electroencephalographic (EEG) activity, and emotional state. Forty-three healthy university students participated. The data collected included heart rate (HR), blood pressure (BP), pulse rate, blood oxygen saturation (SpO2), electroencephalographic (EEG) activity, and the results of the Profile of Mood States (POMS) test. A drop in diastolic pressure (DBP) and pulse rate was also noticed after participants inhaled CCEO. Furthermore, EEG studies have demonstrated notable reductions in absolute beta (AB), absolute gamma (AG), absolute high beta (AHB), and relative gamma (RG) power spectra during exposure to CCEO. Conversely, the relative theta (RT) and power spectra values showed a significant increase. Additionally, the finding from POMS indicated that the fragrance evoked positive emotions and suppressed negative feelings. The results suggest that exposure to CCEO may promote mental and physical relaxation, facilitate cognitive processes such as memory and attention, and enhance mood states.

Effects of Cognitive Demand Levels for Various Horticultural Activities on Psychophysiological Responses in Adults

We compared the effects of horticultural activities according to cognitive demand levels on psychophysiological responses in adults. Thirty-two adults in their 20s were included. Participants performed 10 horticultural activities (raking, planting transplants, fertilizing, tying plants to stakes, harvesting, sowing, conducting cuttage, planting potted plants, cutting and washing, arranging flowers) for 150 seconds at two levels of cognitive demand. Electroencephalographic (EEG) and electrocardiographic measurements were acquired during the activity. After each activity, the participants’ emotional states were evaluated using the semantic differential method (SDM). The EEG results, according to comparison by activity, showed that for nine activities, excluding raking, relative theta decreased when performing tasks at a level of high cognitive difficulty (HCD) compared with those with a low cognitive difficulty (LCD), and relative beta, relative gamma, fast alpha, and relative low beta increased, indicating activation of the prefrontal cortex. In the relative theta power spectra, the cuttage activity was found to be the lowest when performing tasks at a high level high cognitive difficulty, and the working memory function was activated the most compared with other activities. When sowing at a low level of cognitive demand, participants’ heart rate decreased and stabilized. When potted plants were harvested at a high level of cognitive difficulty, the ratio of low frequency to high frequency increased, and the sympathetic nervous system was activated. In addition, when planting transplants, and cutting and washing were performed at a high level of cognitive difficulty, and the standard deviation of the RR interval was high, indicating a high ability of the autonomic nervous system to resist stress. As a result of the SDM, the emotional state according to task difficulty was found to be more stable and relaxed than high cognitive difficulty, but a significant increase in comfort, relaxation, and naturalness was achieved when nine gardening tasks with low cognitive difficulty were performed, with the exception of sowing. The results of this study show that tasks with high cognitive difficulty activate working memory, whereas those with low cognitive difficulty stabilize and relax brain activation. Therefore, this study confirmed that an intervention in horticultural activities with an appropriate level of cognitive difficulty could have a significant effect on psychophysiological changes in adults.

Regional Thermal Radiation Characteristics of FY Satellite Remote Sensing Based on Big Data Analysis.

It is of great significance to study the thermal radiation anomalies of earthquake swarms in the same area in terms of selecting abnormal characteristic determination parameters, optimizing and determining the processing model, and understanding the abnormal machine. In this paper, we investigated short-term and long-term thermal radiation anomalies induced by earthquake swarms in Iran and Pakistan between 2007 and 2016. The anomalies were extracted from infrared remote sensing black body temperature data from the China Geostationary Meteorological Satellites (FY-2C/2E/2F/2G) using the multiscale time-frequency relative power spectrum (MS T-FRPS) method. By analyzing and summarizing the thermal radiation anomalies of series earthquake groups with consistency law through a stable and reliable MS T-FRPS method, we first obtained the relationship between anomalies and ShakeMaps from USGS and proposed the anomaly regional indicator (ARI) to determine seismic anomalies and the magnitude decision factor (MDF) to determine seismic magnitude. In addition, we explored the following discussions: earthquake impact on regional thermal radiation background and the relationship between thermal anomalies and earthquake magnitude and the like. Future research directions using the MS T-FRPS method to characterize regional thermal radiation anomalies induced by strong earthquakes could help improve the accuracy of earthquake magnitude determination.

Resting-State EEG Microstates and Power Spectrum in Borderline Personality Disorder: A High-Density EEG Study

Borderline personality disorder (BPD) is a debilitating psychiatric condition characterized by emotional dysregulation, unstable sense of self, and impulsive, potentially self-harming behavior. In order to provide new neurophysiological insights on BPD, we complemented resting-state EEG frequency spectrum analysis with EEG microstates (MS) analysis to capture the spatiotemporal dynamics of large-scale neural networks. High-density EEG was recorded at rest in 16 BPD patients and 16 age-matched neurotypical controls. The relative power spectrum and broadband MS spatiotemporal parameters were compared between groups and their inter-correlations were examined. Compared to controls, BPD patients showed similar global spectral power, but exploratory univariate analyses on single channels indicated reduced relative alpha power and enhanced relative delta power at parietal electrodes. In terms of EEG MS, BPD patients displayed similar MS topographies as controls, indicating comparable neural generators. However, the MS temporal dynamics were significantly altered in BPD patients, who demonstrated opposite prevalence of MS C (lower than controls) and MS E (higher than controls). Interestingly, MS C prevalence correlated positively with global alpha power and negatively with global delta power, while MS E did not correlate with any measures of spectral power. Taken together, these observations suggest that BPD patients exhibit a state of cortical hyperactivation, represented by decreased posterior alpha power, together with an elevated presence of MS E, consistent with symptoms of elevated arousal and/or vigilance. This is the first study to investigate resting-state MS patterns in BPD, with findings of elevated MS E and the suggestion of reduced posterior alpha power indicating a disorder-specific neurophysiological signature previously unreported in a psychiatric population.

Quantitative Comparison of Brain Waves of Dyslexic Students With Perceptual and Linguistic Types With Normal Students in Reading.

The aim of this study was to compare the brain wave pattern of two groups of dyslexic students with perceptual and linguistic types with normal students in reading. In this study, 27 students (24 boys and 3 girls) from first to fifth grade with an Mean±SD of age 8.16±10.09 years participated. Eight students with perceptual type dyslexia, ten students with linguistic type dyslexia, and nine normal students with reading were selected by purposive sampling method. After removing noise and artifacts, the data were converted into quantitative digits using Neuroguide software and analyzed using multivariate analysis of variance (MANOVA) and univariate analysis of variance (ANOVA). Based on the results, the linguistic group and the normal group differed in the relative power of the alpha wave in the two channels Fp1 and Fp2, but there was no difference between the three linguistic, perceptual, and normal groups in the absolute power of the four waves of the delta, theta, alpha, and beta. The relative power spectrum of the alpha band in the forehead can be significantly related to dyslexia problems as seen in the linguistic type.

Research on thermal infrared anomaly characteristics of moderate strong earthquakes in northeast China

In this article, the daily brightness temperature data from January 2006 to May 2020 of China’s geostationary meteorological satellite FY-2E/G were used to identify the brightness temperature differences before deep and shallow earthquakes in the study area using wavelet transform and the relative wavelet power spectrum (RWPS) methods. The objective was to explore the characteristics of thermal infrared (TIR) radiation anomaly changes before deep and shallow earthquakes in Northeast China by carrying out anomaly extraction and data analysis. The research has shown that five significant earthquakes experienced TIR radiation anomalies in the vicinity of the epicenter approximately 1–2 months before the event. The amplitude of the anomaly ranged from seven to twenty times higher than average, and the anomaly lasted about 3 months. The infrared radiation anomaly characteristics before the earthquake were especially significant in the case of two earthquakes in the Songyuan area. From the research, it was concluded that the TIR radiation anomaly could act as a short-term precursor for earthquake prediction. The method employed in this study would provide great support for predicting deep and shallow earthquakes in Northeast China using satellite thermal infrared technology.

Training Interventions Change Relative Power Spectrum of Alpha After Anterior Cruciate Ligament Deficiency in Athletes

Introduction: In individuals with anterior cruciate ligament deficiency (ACLD), defective sensory and motor neuroplasticity occurs in the central nervous system (CNS) due to defects in sensory afferents. To successfully restore ACLD individuals to pre-injury conditions, it is necessary to modify the neuroplasticity created in the CNS by prescribing more appropriate training. For this aim, in this study, we used perturbation training differently.&#x0D; Materials and Methods: Thirty athletes with unilateral anterior cruciate ligament (ACL) rupture were randomly assigned to the perturbation and standard training groups. The training program of two groups was performed in three intermittent sessions per week for one month. The relative power spectrum of alpha of quantitative electroencephalography (QEEG) was measured in three tasks: (1) the single-leg jump-landing, (2) the single-leg stance with opened eyes, and (3) the single-leg stance with closed eyes.&#x0D; Results: The perturbation training group only showed significant symmetry in the relative power spectrum of alpha between the two limbs in the single-leg jump-landing test (P=0.92, ES=0.04) in comparison pre-post test. Also, this group showed high symmetry in the alpha band in the single-leg stance test with closed eyes (P=0.53, ES=0.16).&#x0D; Conclusion: The results of the present study showed that both mechanical perturbation and standard training are suitable for transporting ACLDs back to sports. It also seems that mechanical perturbation training had higher effectiveness in modifying the CNS alpha power.

Brain-Computer Interface Based on Steady-State Visual Evoked Potential Using Quick-Response Code Pattern for Wheelchair Control.

Brain-computer interfaces (BCIs) are widely utilized in control applications for people with severe physical disabilities. Several researchers have aimed to develop practical brain-controlled wheelchairs. An existing electroencephalogram (EEG)-based BCI based on steady-state visually evoked potential (SSVEP) was developed for device control. This study utilized a quick-response (QR) code visual stimulus pattern for a robust existing system. Four commands were generated using the proposed visual stimulation pattern with four flickering frequencies. Moreover, we employed a relative power spectrum density (PSD) method for the SSVEP feature extraction and compared it with an absolute PSD method. We designed experiments to verify the efficiency of the proposed system. The results revealed that the proposed SSVEP method and algorithm yielded an average classification accuracy of approximately 92% in real-time processing. For the wheelchair simulated via independent-based control, the proposed BCI control required approximately five-fold more time than the keyboard control for real-time control. The proposed SSVEP method using a QR code pattern can be used for BCI-based wheelchair control. However, it suffers from visual fatigue owing to long-time continuous control. We will verify and enhance the proposed system for wheelchair control in people with severe physical disabilities.

High-Frequency Local Field Potential Oscillations May Modulate Aggressive Behaviors in Mice.

Aggressive behavior is one of congenital social behaviors in many species, which could be promoted by social neglect or isolation in the early stages of life. Many brain regions including the medial prefrontal cortex (mPFC), medial amygdala (MeA) and ventromedial hypothalamus (VMH) are demonstrated to relate to aggressive behavior; however, the dynamic patterns of neural activities during the occurrence of this behavior remain unclear. In this study, 21-day-old male CD-1 mice were reared in social isolation conditions and cohousing conditions for two weeks. Aggressive behaviors of each subject were estimated by the resident-intruder test. Simultaneously, the local field potentials of mPFC, MeA and VMH were recorded for exploring differences in the relative power spectra of different oscillations when aggressive behaviors occurred. The results showed that the following: (1) Compared with the cohousing mice, the socially isolated mice exhibited more aggression. (2) Regardless of "time condition" (pre-, during- and post- attack), the relative power spectra of beta band in the cohousing mice were significantly greater than those in the socially isolated mice, and inversely, the relative power spectra of gamma band in the cohousing mice were significantly smaller than those in the socially isolated mice. (3) The bilateral mPFC exhibited significantly smaller beta power spectra but greater gamma power spectra compared with other brain areas regardless of rearing patterns. (4) For the right VMH of the socially isolated mice, the relative power spectra of the gamma band during attacks were significantly greater than those before attack. These results suggest that aggressive behaviors in mice could be shaped by rearing patterns and that high-frequency oscillations (beta and gamma bands) may engage in mediating aggressive behaviors in mice.

Quantitative pretreatment EEG predicts efficacy of ACTH therapy in infantile epileptic spasms syndrome

ObjectiveThis study aimed to determine the correlation between outcomes following adrenocorticotrophic hormone (ACTH) therapy and measurements of relative power spectrum (rPS), weighted phase lag index (wPLI), and graph theoretical analysis on pretreatment electroencephalography (EEG) in infants with non-lesional infantile epileptic spasms syndrome (IESS). MethodsTwenty-eight patients with non-lesional IESS were enrolled. Outcomes were classified based on seizure recurrence following ACTH therapy: seizure-free (F, n = 21) and seizure-recurrence (R, n = 7) groups. The rPS, wPLI, clustering coefficient, and betweenness centrality were calculated on pretreatment EEG and were statistically analyzed to determine the correlation with outcomes following ACTH therapy. ResultsThe rPS value was significantly higher in the delta frequency band in group R than in group F (p < 0.001). The wPLI values were significantly higher in the delta, theta, and alpha frequency bands in group R than in group F (p = 0.007, <0.001, and <0.001, respectively). The clustering coefficient in the delta frequency band was significantly lower in group R than in group F (p < 0.001). ConclusionsOur findings demonstrate the significant differences in power and functional connectivity between outcome groups. SignificanceThis study may contribute to an early prediction of ACTH therapy outcomes and thus help in the development of appropriate treatment strategies.

Developing Disposable EEG Cap for Infant Recordings at the Neonatal Intensive Care Unit.

Long-term EEG monitoring in neonatal intensive care units (NICU) is challenged with finding solutions for setting up and maintaining a sufficient recording quality with limited technical experience. The current study evaluates different solutions for the skin–electrode interface and develops a disposable EEG cap for newborn infants. Several alternative materials for the skin–electrode interface were compared to the conventional gel and paste: conductive textiles (textured and woven), conductive Velcro, sponge, super absorbent hydrogel (SAH), and hydro fiber sheets (HF). The comparisons included the assessment of dehydration and recordings of signal quality (skin interphase impedance and powerline (50 Hz) noise) for selected materials. The test recordings were performed using snap electrodes integrated into a forearm sleeve or a forehead band along with skin–electrode interfaces to mimic an EEG cap with the aim of long-term biosignal recording on unprepared skin. In the hydration test, conductive textiles and Velcro performed poorly. While the SAH and HF remained sufficiently hydrated for over 24 h in an incubator-mimicking environment, the sponge material was dehydrated during the first 12 h. Additionally, the SAH was found to have a fragile structure and was electrically prone to artifacts after 12 h. In the electrical impedance and recording comparisons of muscle activity, the results for thick-layer HF were comparable to the conventional gel on unprepared skin. Moreover, the mechanical instability measured by 1–2 Hz and 1–20 Hz normalized relative power spectrum density was comparable with clinical EEG recordings using subdermal electrodes. The results together suggest that thick-layer HF at the skin–electrode interface is an effective candidate for a preparation-free, long-term recording, with many advantages, such as long-lasting recording quality, easy use, and compatibility with sensitive infant skin contact.

TEC Anomalies Detection for Qinghai and Yunnan Earthquakes on 21 May 2021

Earthquake prediction by using total electron content is a commonly used seismic research method. The long short-term memory model is a kind of method to predict time series and has been used for the prediction of total electron content, and the relative power spectrum method is one of the pre-seismic infrared anomaly detection algorithms in the frequency domain. In this paper, a new method combining these two algorithms is used to extract abnormal signals; thus scientists can more easily detect anomalies of total electron content similar to those before the Qinghai and Yunnan earthquakes happened on 21 May 2021. There are pre-seismic anomalies with the high-value relative power spectrum near two epicenters. To validate the correlation between anomalies and earthquakes statistically, the spatiotemporal characteristics of TEC anomalies are analyzed based on connected region recognition. Then, the proportion of earthquake-related anomalies (the correlation rate), the proportion of earthquakes outside the predicted range (the miss rate), and the ratio of the proportion of earthquakes within the predicted range to the spatiotemporal occupancy of anomalies, which is called the probability gain, were used to assess the method. The appropriate parameters of the algorithm for the miss rate below 50% were searched. The highest probability gain is 1.91, which means anomalies of total electron content may decrease the uncertainty of earthquake prediction.

Statistical and Comparative Analysis of Multi-Channel Infrared Anomalies before Earthquakes in China and the Surrounding Area

Abundant infrared remote sensing images and advanced information processing technologies are used to predict earthquakes. However, most studies only use single long-wave infrared data or its products, and the accuracy of prediction is not high enough. To solve this problem, this paper proposes a statistical method based on connected domain recognition to analyze multi-channel anomalies. We extract pre-seismic anomalies from multi-channel infrared remote sensing images using the relative power spectrum, then calculate positive predictive values, true positive rates and probability gains in different channels. The results show that the probability gain of the single-channel prediction method is extremely low. The positive predictive value of four-channel anomalies is 41.94%, which is higher than that of single-channel anomalies with the same distance threshold of 200 km. The probability gain of the multi-channel method is 2.38, while that of the single-channel method using the data of any channel is no more than 1.26. This study shows the advantages of the multi-channel method to predict earthquakes and indicates that it is feasible to use multi-channel infrared remote sensing images to improve the accuracy of earthquake prediction.

Thermal Aging Evaluation of XLPE Power Cable by Using Multidimensional Characteristic Analysis of Leakage Current.

Thermal aging is a common form of cable deterioration. In this paper, the effect of thermal aging on cables is evaluated by analyzing the harmonic characteristics in cable leakage currents. Cable samples were first fabricated and subjected to accelerated thermal aging tests at 120 °C. The experimental circuits were built to test the dielectric loss factor and the AC leakage current of the cable at different aging times. Then, the improved variational modal decomposition (VMD) algorithm was used for the time–frequency analysis of the leakage current, and the relationship between thermal aging and leakage current harmonics was investigated. Thermal aging was discovered to increase the capacitance and dielectric loss factor of the cable as well as generate harmonics in the leakage current, with harmonics at 150, 450, and 650 Hz being particularly sensitive to thermal aging. The multidimensional characteristic parameters such as the time-domain, frequency-domain, and relative energy and the sample entropy of the leakage current harmonics were calculated. The results demonstrated thermal aging increased the relative energy and power spectrum energy of the harmonics and increased the disorder of the harmonic sequence.

Corticomuscular Adaptations in the SingleLeg Jump Task in Response to Progressive Mechanical Perturbation Training in Individuals With Anterior Cruciate Ligament Deficiency

Introduction: Studies have repeatedly discussed the importance of training with sufficient cognitive and sensory-motor challenges in successfully transferring Anterior Cruciate Ligament Deficiencies (ACLDs) from rehabilitation centers to sports facilities. For this purpose, this study investigated the effect of mechanical perturbation training and standard training on the brain and muscle activity of these individuals while jumping on one leg. Materials and Methods: A total of 30 athletes with unilateral Anterior Cruciate Ligament (ACL) rupture (in the coper classification) were randomly assigned to perturbation and standard training groups. To compare the effect of two types of intervention training methods, we examined the Similarity Index (SI) and Voluntary Response Index (VRI) in surface Electromyography (sEMG) tests of eight muscles in the lower extremities and relative power of alpha and beta spectra in Quantitative Electroencephalographic (QEEG) tests between two groups and between two limbs of each group members in the single-leg jump task. Results: Both training groups showed improved neuromuscular control and increased SI on sEMG tests between the two limbs. However, this improvement in the perturbation training group showed an excellent increase in Effect Size (ES) (intra-group comparison values of SI for perturbation training group P=0.0001, ES=3.6; and P=0.008, ES=1.24 in the standard training group; and P=0.04, ES=0.87 in the inter-group comparison). Regarding the post-test of QEEG tests, no significant difference was found between the two groups (alpha P-value: 0.13, beta P-value: 0.07). However, in the intra-group comparison, the perturbation training group achieved excellent symmetry for the relative power spectrum of alpha and beta signals (the similarity values between the two limbs in the perturbation training group for alpha were P=0.92, ES=0.04 and for beta were P=0.92, ES=0.02; and these values for standard training group for alpha were P=0.07, ES=0.86 and for beta as P=0.08, ES=0.87). Conclusion: The present study results showed that mechanical perturbation and standard training are suitable for transporting ACLDs to sports environments. Furthermore, in comparing these two training methods, mechanical perturbation training in the manner used in this study has higher adequacy to eliminate motor control and central nervous system defects.

Does Quantitative Electroencephalography Refine Preoperative Cognitive Assessment in Parkinson’s Disease Patients Treated with Deep Brain Stimulation? A Follow-Up Study

Objective: Deep brain stimulation (DBS) in Parkinson’s disease (PD) is associated with an increased risk of post-operative cognitive deterioration. Preoperative neuropsychological testing can be affected and limited by the patient’s collaboration in advanced disease. The purpose of this study was to determine whether preoperative quantitative electroencephalography (qEEG) may be a useful complementary examination technique during preoperative assessment to predict cognitive changes in PD patients treated with DBS. Methods: We compared the cognitive performance of 16 PD patients who underwent bilateral subthalamic nucleus DBS to the performance of 15 PD controls (matched for age, sex, and education) at baseline and at 24 months. Cognitive scores were calculated for all patients across 5 domains. A preoperative 256-channel resting EEG was recorded from each patient. We computed the global relative power spectra. Correlation and linear regression models were used to assess associations of preoperative EEG measures with post-operative cognitive scores. Results: Slow waves (relative delta and theta band power) were negatively correlated with post-operative cognitive performance, while faster waves (alpha 1) were strongly positively correlated with the same scores (the overall cognitive score, attention, and executive function). Linear models revealed an association of delta power with the overall cognitive score (p = 0.00409, adjusted R² = 0.6341). Verbal fluency (VF) showed a significant decline after DBS surgery, which was correlated with qEEG measures. Conclusions: To analyse the side effects after DBS in PD patients, the most important parameter is verbal fluency capacity. In addition, correlation with EEG frequency bands might be useful to detect particularly vulnerable patients for cognitive impairment and be supportive in the selection process of patients considered for DBS.

P 37. The cognitive course in Parkinson's disease patients treated with Deep Brain Stimulation of subthalamic nucleus – Correlations with qEEG

Objective. Deep brain stimulation of the subthalamic nucleus (STN-DBS) improve motor functioning in Parkinson“s disease patients– Additionally it can also influence cognitive functioning. In most patients, a decline of verbal fluency test performance after STN-DBS is often reported. The purpose of this study was to determine whether preoperative quantitative electroencephalography (qEEG) may be useful in the preoperative assessment predicting cognitive changes in PD patients treated with STN-DBS. Methods. We compared the cognitive performance of 16 PD patients who underwent bilateral STN-DBS and 15 PD controls (matched for age, sex and education) at baseline as well as after 24 months. Cognitive scores were calculated for all patients across 5 cognitive domains covered by different cognitive tests (attention, executive function, episodic & working memory, verbal fluency, visuo-construction). A preoperative 256-channels EEG was recorded of each patient at rest and global relative power spectra were computed. Correlation and linear regression models were used to assess the association of preoperative EEG measures with postoperative cognitive scores in stimulated PD patients compared to PD controls. Results. The decline of verbal fluency performance after two years in the PD group treated with STN-DBS was significant in comparison to the PD controls ( p < 0.001). All other cognitive domains declined in the same manner as in the PD controls or remained stable over the 24-months period. EEG frequency analyses revealed increased global theta power (4-8 Hz) at baseline to be associated with reduced postoperative verbal fluency performance ( r = 0.50, p < 0.05) at follow-up. Conclusion. Consistent with the results of former studies, STN stimulation deteriorates verbal fluency in the course of two years. Accordingly, we observed significant decline in tests measuring verbal fluency in the group of PD patients treated with STN-DBS compared to a control group of PD patients. The decline of verbal fluency performance could be predicted by a reduced theta power at baseline. No other significant differences in cognitive alterations between patients in the STN-DBS group and the PD control group occur over two years.