EEG Changes Research Articles

The Effect of Therapeutic Hypothermia on Serum Carboxy-Terminal Hydrolase L1 and Amplitude EEG Changes in Hypoxic-Ischemic Neonates

Abstract Background Hypoxia-ischemic encephalopathy (HIE) is one of the most important complications of the newborn period. It is the result of depriving nerve tissue of oxygen and glucose, which may be the result of either hypoxia or ischemia. Objective To assess effect of therapeutic hypothermia (TH) on EEG changes and Carboxy-terminal hydrolase L1level in neonatal HIE at Al-Zahraa university and El Haram hospitals. Patients and Methods This was a prospective comparative study that was conducted at the NICU unit Al ZahraaUniversity and El Haram hospitals for a period from (May 2020 till June 2022). This study included 50 full term newborns (37 to 40 weeks of gestational age) with clinical and laboratory evidence of HIE II–III, They were divided into two groups: Group 1: 25 HIE neonates who were treated with therapeutic hypothermia and group 2: 25 HIE neonates who weren’t received therapeutic hypothermia. Newborns with congenital anomalies, intracranial lesion, epileptic seizure, spinal cord injury or cardiac arrest were excluded from the study. We record EEG changes during 72 hrs by an electroencephalogram with a bioelectric amplifier (Deltamed, Bourgogne), (Philips) Screen. Blood samples were analyzed for UCH-L1 levels by (SEG945Mi). The neonates involved in cooling group were placed over a cooling blanket (Blanketrol III), for 72 hours. Results The results showed there was statistically significant relation between high UCH-L1 level and higher grades of the Sarnat score and primitive reflexes of both the cooling group and non cooling group. The results also showed that there were lower levels of UCH-L1 in cooling group compared to non cooling group of the studied neonates Also there was significant negative correlation found between UCH-L1 level and PH, and HCO3 values. This study showed that there was statistically significant relation found between UCH-L1 level and EEG recording on the 3rd day of both the studied groups. This study showed that (84%) of the non cooling group had EEG abnormalities compared to (68%) of the cooling group. Among both groups of the studied neonates, 76% had EEG abnormalities in form of (34%) had suppression EEG, (16%) were occipito-temporal, (20%) fronto-temporal and (6%) centro-parital. Regarding the site of EEG abnormality (18%) were right sided, (24%) were left sided. The study showed that 72% of cooling group were discharged compared to 48% of non cooling group. Conclusion From our study we concluded significant improvement in EEG records in ischemic neonates who were treated with therapeutic hypothermia. UCH- L1 is a good early neuronal injury biomarker for detecting severity of HIE P value < 0.001 and is a good predictor of hypoxia with specificity 92% and ppv 86.7% and NPV 65.7%. Therapeutic hypothermia has been noted to reduce severe disability among survivors.

The Surgical Method of Craniectomy Differentially Affects Acute Seizures, Brain Deformation and Behavior in a TBI Animal Model.

Traumatic brain injury (TBI) is the leading cause of morbidity and mortality worldwide. Multiple injury models have been developed to study this neurological disorder. One such model is the lateral fluid-percussion injury (LFPI) rodent model. The LFPI model can be generated with different surgical procedures that could affect the injury and be reflected in neurobehavioral dysfunction and acute EEG changes. A craniectomy was performed either with a trephine hand drill or with a trephine electric drill that was centered over the left hemisphere of adult, male Sprague Dawley rats. Sham craniectomy groups were assessed by hand-drilled (ShamHMRI) and electric-drilled (ShamEMRI) to evaluate by MRI. Then, TBI was induced in separate groups (TBIH) and (TBIE) using a fluid-percussion device. Sham-injured rats (ShamH/ShamE) underwent the same surgical procedures as the TBI rats. During the same surgery session, rats were implanted with screw and microwire electrodes positioned in the neocortex and hippocampus and the EEG activity was recorded 24 hours for the first 7 days after TBI for assessing the acute EEG seizure and Gamma Event Coupling (GEC). The electric drilling craniectomy induced greater tissue damage and sensorimotor deficits compared to the hand drill. Analysis of the EEG revealed acute seizures in at least one animal from each group after the procedure. Both TBI and Sham rats from the electric drill groups had a significant greater total number of seizures than the animals that were craniectomized manually (p<0.05). Similarly, EEG functional connectivity was lower in ShamE compared to ShamH rats. These results suggest that electrical versus hand drilling craniectomies produce cortical injury in addition to the LFPI which increases the likelihood for acute post-traumatic seizures. Differences in the surgical approach could be one reason for the variability in the injury that makes it difficult to replicate results between preclinical TBI studies.

Application of Mozart's Sonata for Two Pianos in D Major in Children with Epilepsy and Effect of Acoustic Quality on Epileptic Discharges.

Mozart's Sonata for Two Pianos in D Major (K448) is a classic double piano work. This study investigated its effect on children with epilepsy (EP) and analyzed the changes in electroencephalography (EEG) among children on the basis of acoustic quality. The clinical data of 150 children with EP in the Affiliated Hospital (Group) of Putian University from March 2020 to March 2023 were retrospectively analyzed. They were divided into group A (n = 73, antiepileptic drug therapy) and group B (n = 77, antiepileptic drug therapy + Mozart K448) in accordance with the treatment methods. The seizure frequency, frequency of epileptic discharges (EDs), and Quality of Life in Childhood Epilepsy Questionnaire-16 in both groups were compared before and after treatment. The changes in EEG before, during, and after music appreciation were observed. The effects of the acoustic characteristics (rhythm, root mean square value, roughness, and spectral flux) of Mozart K448 on EDs in children were explored. After treatment, group A had a higher seizure frequency (P < 0.001), a higher frequency of EDs (P < 0.05), and significantly lower scores of cognition and emotion than group B (P < 0.001), without significant difference in the scores of social function and physical function (P > 0.05). The frequency of EDs before music appreciation was significantly higher than that during music appreciation (P < 0.01). Spearman correlation analysis showed that the rhythm, spectral flux, and roughness in Mozart K488 were related to the decrease in EDs among children with EP (P < 0.001). This study confirmed the application effect of Mozart K448 in children with EP. Mozart K448 can decrease the seizure frequency, reduce the ED occurrence, and improve the quality of life. The acoustic characteristics of K448 may be the reason for improving EP in children.

Refraining from spontaneous face touch is linked to personality traits, reduced memory performance and EEG changes

Spontaneous touches of one’s face (sFST) were suggested to serve cognitive-emotional regulation processes. During the pandemic, refraining from face-touching was recommended, yet, accompanying effects and the influence of personal attributes remain unclear. Ninety participants (45 female, 45 male) filled out a questionnaire concerning personality, anxiety screening and ADHD screening. Subsequently, they performed a delayed verbal memory recall task four times. After two times, sixty participants were instructed to refrain from face-touching (experimental group). Thirty participants did not receive behavioral instructions (control group). To identify face-touches and conduct further analysis, Video, EMG, and EEG data were recorded. Two samples were formed, depending on the adherence to completely refrain from face-touching (adherent, non-adherent sample) and compared to each other and the control group. EEG analyses uncovered that refraining from face-touching is accompanied by increased beta-power at sensorimotor sites and, exclusively in the non-adherent sample, at frontal sites. Decreased memory performance was found exclusively in subsamples, who non-adherently touched their face while retaining words. In terms of questionnaire results, lower Conscientiousness and higher ADHD screening scores were revealed by the non-adherent compared to the adherent sample. No differences were found among the subsamples. The presented results indicate that refraining from face-touching is related to personal attributes, accompanied by neurophysiological shifts and for a portion of humans by lower memory performance, supporting the notion that sFST serve processes beyond sensorimotor.

Interictal Electroencephalography and Functional Magnetic Resonance Imaging Reveals Involvement of Mesial Anterior Frontal Structures in Patients With Hyperkinetic Semiology Type I.

This work investigates the presence of common anatomic regions associated with interictal activity in patients with hyperkinetic seizures type I by means of concurrent electroencephalography and functional magnetic resonance imaging. Six patients with hyperkinetic seizures type I were evaluated with video-EEG and electroencephalography and functional magnetic resonance imaging in the context of their presurgical evaluation. Statistical Parametric Mapping was used to perform a correlation study between the occurrence of interictal spikes on EEG and suprathreshold blood oxygen level-dependent changes in the whole-brain volume. In all patients, Statistical Parametric Mapping revealed suprathreshold blood oxygen level-dependent clusters in the mesial anterior frontal areas, including the rostral mesial superior frontal gyrus and the anterior cingulate, associated with the patients' typical interictal activity. The electroencephalography and functional magnetic resonance imaging findings contribute to our understanding of hyperkinetic seizures type I semiology generation and can inform stereo-EEG targeting for surgical planning in refractory cases.

EEG signatures of cognitive decline after mild SARS-CoV-2 infection: an age-dependent study

BackgroundCurrent research on the neurological impact of SARS-CoV-2 primarily focuses on the elderly or severely ill individuals. This study aims to explore the diverse neurological consequences of SARS-CoV-2 infection, with a particular focus on mildly affected children and adolescents.MethodsA cohort study was conducted to collect pre- and post-infection resting-state electroencephalogram (EEG) data from 185 participants and 181 structured questionnaires of long-term symptoms across four distinct age groups. The goal was to comprehensively evaluate the impact of SARS-CoV-2 infection on these different age demographics. The study analyzed EEG changes of SARS-CoV-2 by potential biomarkers across age groups using both spatial and temporal approaches.ResultsSpatial analysis indicated that children and adolescents exhibit smaller changes in brain network and microstate patterns post-infection, implying a milder cognitive impact. Sequential linear analyses showed that SARS-CoV-2 infection is associated with a marked rise in low-complexity, synchronized neural activity within low-frequency EEG bands. This is evidenced by a significant increase in Hjorth activity within the theta band and Hjorth mobility in the delta band. Sequential nonlinear analysis indicated a significant reduction in the Hurst exponent across all age groups, pointing to increased chaos and complexity within the cognitive system following infection. Furthermore, linear regression analysis based on questionnaires established a significant positive relationship between the magnitude of changes in these neural indicators and the persistence of long-term symptoms post-infection.ConclusionsThe findings underscore the enduring neurological impacts of SARS-CoV-2 infection, marked by cognitive decline and increased EEG disarray. Although children and adolescents experienced milder effects, cognitive decline and heightened low-frequency electrical activity were evident. These observations might contribute to understanding potential anxiety, insomnia, and neurodevelopmental implications.

Effect of aromatic massage on brain waves and physiological indices of older adults.

Massage and aromatherapy are frequently used by older adults as alternative interventions to enhance immunity and induce relaxation. This pilot study evaluated the effect of massage therapy with oil and aromatherapy alone and in combination using objective biological indices. Twenty-eight participants recruited by convenience sampling included adults aged between 25 and 65 years (Group 1), elderly individuals over 65 years without nursing care (Group 2), and older adults over 65 needing long-term nursing support (Group 3). A multiple-group pretest-post-test design was employed, and the effect among the three groups was compared. Interventions included: (i) oil massage therapy; (ii) aromatherapy; and (iii) aroma oil massage therapy. Each therapy session lasted 5 min, with 3 min of observation before and after the session and 10 min interval between sessions. Group 3 omitted one therapy (2: aromatherapy) to reduce their physical burden. An electroencephalogram (EEG) was recorded for α, β, and θ activities of brain waves. EEG data were collected at three points: before, during, and after each treatment. Salivary secretory immunoglobulin A (s-IgA) concentration, oxygen saturation (SPO2), and pulse rate were measured before and after each session. Across all therapy modalities, there was a noticeable increase in the α wave, indicative of relaxation, during the treatment. Significant differences were observed before and during the oil massage in both Group 1 and Group 2. Aromatherapy demonstrated a significant difference before and during treatment in Group 1. Among the biological parameters, s-IgA levels indicated no significant changes. The pulse rate decreased with oil massage. Significant differences were noted before and after therapy in all cases for SPO2 and in Group 2 for pulse rate. Three therapies induced EEG and physiological changes in the adult group and older adults without nursing care. However, these effects are limited in older adults requiring nursing care.

Diffuse microglial responses and persistent EEG changes correlate with poor neurological outcome in a model of subarachnoid hemorrhage

The mechanism by which subarachnoid hemorrhage (SAH) leads to chronic neurologic deficits is unclear. One possibility is that blood activates microglia to drive inflammation that leads to synaptic loss and impaired brain function. Using the endovascular perforation model of SAH in rats, we investigated short-term effects on microglia together with long-term effects on EEG and neurologic function for up to 3 months. Within the first week, microglia were increased both at the site of injury and diffusely across the cortex (2.5-fold increase in SAH compared to controls, p = 0.012). Concomitantly, EEGs from SAH animals showed focal increases in slow wave activity and diffuse reduction in fast activity. When expressed as a fast-slow spectral ratio, there were significant interactions between group and time (p < 0.001) with less ipsilateral recovery over time. EEG changes were most pronounced during the first week and correlated with neurobehavioral impairment. In vitro, the blood product hemin was sufficient to increase microglia phagocytosis nearly six-fold (p = 0.032). Immunomodulatory treatment with fingolimod after SAH reduced microglia, improved neurological function, and increased survival. These findings, which parallel many of the EEG changes seen in patients, suggest that targeting neuroinflammation could reduce long-term neurologic dysfunction following SAH.

How taking pictures of landscapes affects the mental stress of young adults

AbstractIn today's fast‐paced society, escalating work and academic pressures have led to rising stress levels. While numerous studies have explored adolescent mental health, there has been a lack of focus on “educational stress” among Chinese students. This study sought to understand the psychological and physiological effects of educational stress in Chinese university students. We studied the impact of a 5‐min nature photography session on campus compared with a control activity of photographing urban settings near campus. Data were collected using blood pressure measurements, electroencephalography (EEG), the Semantic Differential Method (SDM), and the State–Trait Anxiety Inventory (STAI) in order to understand psychophysiological reactions. The findings from the SDM and STAI assessments indicated that students felt slightly more at ease and considerably more relaxed, had a heightened sense of naturalness, and experienced reduced anxiety after engaging in nature photography compared with urban photography. Notably, we observed that both systolic and diastolic blood pressure dropped by many values and there were noticeable EEG changes among participants. The results suggest that a brief 5‐min nature photography activity can effectively reduce mental stress in Chinese university students.

EEG를 활용한 사람중심 커뮤니케이션 중재 효과성 연구

Person-Centered care and communication intervention have been widely utilized in emotional care for people with dementia overseas. However, the use of non-pharmacological interventions, including person-centered care, has been lacking in Korea primarily due to a shortageof scientific evidence proving their efficacy. This study aimed to present Person-Centered communication as a method of intervention andto quantitatively assess its impact on the emotional state and agitation of people with dementia. The subjects of the study, people withmild dementia who commute day care centers, were divided into experimental and control groups for the purpose of comparison. Measurementson brainwaves and observations on changes in emotion and behavior were taken before and after the interventions. Brainwaves were examined by measuring signals from two electrodes of EEG on the prefrontal cortex, and observation were taken with the Observed Emotion RateScale (OERS) and the Agitation Behavior Scale (ABS). As a result of the communication intervention, it was found that emotions such as happiness and attentiveness increased, while anger, anxiety·agitation, and sadness decreased, along with a reduction in agitated behavior. EEG measurements showed a decrease in theta waves which are related to emotions, and significant changes in alpha and beta waves whichare related to attentiveness. This study is meaningful in that it quantitatively confirmed the effectiveness of Person-Centered communicationon the emotions and agitated behavior, as well as EEG changes in people with mild dementia. This study suggests using Person-Centered Care and communication intervention for the emotional support of people with dementia.

Analysis and recognition of a novel experimental paradigm for musical emotion brain-computer interface

Musical emotions have received increasing attention over the years. To better recognize the emotions by brain-computer interface (BCI), the random music-playing and sequential music-playing experimental paradigms are proposed and compared in this paper. Two experimental paradigms consist of three positive pieces, three neutral pieces and three negative pieces of music. Ten subjects participate in two experimental paradigms. The features of electroencephalography (EEG) signals are firstly analyzed in the time, frequency and spatial domains. To improve the effect of emotion recognition, a recognition model is proposed with the optimal channels selecting by Pearson’s correlation coefficient, and the feature fusion combining differential entropy and wavelet packet energy. According to the analysis results, the features of sequential music-playing experimental paradigm are more different among three emotions. The classification results of sequential music-playing experimental paradigm are also better, and its average results of positive, neutral and negative emotions are 78.53%, 72.81% and 77.35%, respectively. The more obvious the changes of EEG induced by the emotions, the higher the classification accuracy will be. After analyzing two experimental paradigms, a better way for music to induce the emotions can be explored. Therefore, our research offers a novel perspective on affective BCIs.

Role of Intraoperative Electroencephalography in Predicting Postoperative Delirium in Patients Undergoing Cardiovascular Surgeries

ObjectiveTo determine the utility of electroencephalography (EEG) in predicting postoperative delirium (POD) in patients who underwent cardiovascular surgeries with EEG monitoring. MethodsA total of 1161 patients who underwent cardiovascular surgeries with EEG monitoring were included in the study, and their data were retrospectively reviewed. POD assessment was done utilizing Intensive Care Delirium Screening Checklist (ICDSC). Patients with a score of > 4 on ICDSC were diagnosed with POD. ResultsOf 1161 patients, 131 patients had EEG changes and 56 (42.74%) of 131 patients experienced POD. Of 1030 patients without EEG changes, 219 (21.26%) experienced POD. EEG showed specificity of 91.5% and negative predictive value of 78.7% in detecting POD. On multivariable analysis, EEG changes showed a strong association with POD (ORadj 1.97 CI (1.30–2.99), p = 0.001) with persistent EEG changes showing even a higher risk of developing POD (ORadj 2.65 (1.43–4.92), p = 0.002). ConclusionEEG change has specificity of 91.5% emphasizing the need for its implementation as a diagnostic tool for predicting POD. Patients with POD are two times more likely to experience significant EEG changes, especially persistent EEG changes when undergoing cardiovascular surgeries. SignificanceIntraoperative EEG can detect POD, and EEG changes based therapeutic interventions can mitigate POD.

Abnormal resting-state EEG phase dynamics distinguishes major depressive disorder and bipolar disorder

Changes in EEG have been reported in both major depressive disorder (MDD) and bipolar disorder (BD). Specifically, power changes in EEG alpha and theta frequency bands during rest and task are known in both disorders. This leaves open whether there are changes in yet another component of the electrophysiological EEG signal, namely phase-related processes that may allow for distinguishing MDD and BD. For that purpose, we investigate EEG-based spontaneous phase in the resting state of MDD, BD and healthy controls. Our main findings show: (i) decreased spontaneous phase variability in frontal theta of both MDD and BD compared to HC; (ii) decreased spontaneous phase variability in central-parietal alpha in MDD compared to both BD and HC; (iii) increased delays or lags of alpha phase cycles in MDD (but not in BD), which (iv) correlate with the decreased phase variability in MDD. Together, we show similar (decreased frontal theta variability) and distinct (decreased central-parietal alpha variability with increased lags or delays) findings in the spontaneous phase dynamics of MDD and BD. This suggests potential relevance of theta and alpha phase dynamics in distinguishing MDD and BD in clinical differential-diagnosis.

EEG Changes in Migraine—Can EEG Help to Monitor Attack Susceptibility?

Migraine is a highly prevalent brain condition with paroxysmal changes in brain excitability believed to contribute to the initiation of an attack. The attacks and their unpredictability have a major impact on the lives of patients. Clinical management is hampered by a lack of reliable predictors for upcoming attacks, which may help in understanding pathophysiological mechanisms to identify new treatment targets that may be positioned between the acute and preventive possibilities that are currently available. So far, a large range of studies using conventional hospital-based EEG recordings have provided contradictory results, with indications of both cortical hyper- as well as hypo-excitability. These heterogeneous findings may largely be because most studies were cross-sectional in design, providing only a snapshot in time of a patient’s brain state without capturing day-to-day fluctuations. The scope of this narrative review is to (i) reflect on current knowledge on EEG changes in the context of migraine, the attack cycle, and underlying pathophysiology; (ii) consider the effects of migraine treatment on EEG features; (iii) outline challenges and opportunities in using EEG for monitoring attack susceptibility; and (iv) discuss future applications of EEG in home-based settings.

Quantitative EEG analysis of brivaracetam in drug-resistant epilepsy: A pharmaco-EEG study

ObjectiveBrivaracetam (BRV) is a recent antiseizure medication (ASM) approved as an add-on therapy for people with focal epilepsy. BRV has a good efficacy and safety profile compared to other ASMs. However, its specific effects on resting-state EEG activity and connectivity are unknown. The aim of this study is to evaluate quantitative EEG changes induced by BRV therapy in a population of adult people with drug-resistant epilepsy (PwE) compared to healthy controls (HC). MethodsWe performed a longitudinal, retrospective, pharmaco-EEG study on a population of 23 PwE and a group of 25 HC. Clinical outcome was dichotomized into drug-responders (i.e., >50% reduction in seizures’ frequency; RES) and non-responders (N-RES) after two years of BRV. EEG parameters were compared between PwE and HC at baseline (pre-BRV) and after three months of BRV therapy (post-BRV). We investigated BRV-related variations in EEG connectivity using the phase locking value (PLV). ResultsBRV therapy did not induce modifications in power spectrum density across different frequency bands. PwE presented lower PLV connectivity values compared to HC in all frequency bands. RES exhibited lower theta PLV connectivity compared to HC before initiating BRV and experienced an increase after BRV, eliminating the significant difference from HC. ConclusionsThis study shows that BRV does not alter the EEG power spectrum in PwE, supporting its favourable neuropsychiatric side-effect profile, and induces the disappearance of EEG connectivity differences between PwE and HC. SignificanceThe integration of EEG quantitative analysis in epilepsy can provide insights into the efficacy, mechanism of action, and side effects of ASMs.

Unilateral cortical autoimmune encephalitis: A case series and comparison to late-onset Rasmussen's encephalitis

ObjectiveTo report a novel anatomical pattern of autoimmune encephalitis characterized by strictly unilateral cortical inflammation and a clinical picture overlapping with late-onset Rasmussen's encephalitis. MethodsWe retrospectively gathered data of patients identified at two tertiary referral academic centers who met inclusion criteria. ResultsWe identified twelve cases (average age 65, +/− 19.8 years, 58% female). All patients had unilateral cortical inflammation manifesting with focal seizures, cognitive decline, hemicortical deficits, and unilateral MRI and/or EEG changes. Six cases were idiopathic, two paraneoplastic, two iatrogenic (in the setting of immune checkpoint inhibitors), and two post-COVID-19. Serologically, ten patients were seronegative, one had high titer anti-GAD65, and one had anti-NMDAR. Five patients met Rasmussen's encephalitis criteria, and six did not fully meet the criteria but had symptoms significantly overlapping with the condition. Most patients had significant improvement with immunotherapy. DiscussionUnilateral cortical AE seems to be more prevalent in the elderly and more frequently idiopathic and seronegative. Patients with this anatomical variant of autoimmune encephalitis have overlapping features with late-onset Rasmussen's encephalitis but are more responsive to immunotherapy. In cases refractory to immunotherapy, interventions used in refractory Rasmussen's encephalitis may be considered, such as functional hemispherectomy.

Late-Onset Findings During Extended EEG Monitoring Are Rare in Critically Ill Children.

Electrographic seizures (ES) are common in critically ill children undergoing continuous EEG (CEEG) monitoring, and previous studies have aimed to target limited CEEG resources to children at highest risk of ES. However, previous studies have relied on observational data in which the duration of CEEG was clinically determined. Thus, the incidence of late occurring ES is unknown. The authors aimed to assess the incidence of ES for 24 hours after discontinuation of clinically indicated CEEG. This was a single-center prospective study of nonconsecutive children with acute encephalopathy in the pediatric intensive care unit who underwent 24 hours of extended research EEG after the end of clinical CEEG. The authors assessed whether there were new findings that affected clinical management during the extended research EEG, including new-onset ES. Sixty-three subjects underwent extended research EEG. The median duration of the extended research EEG was 24.3 hours (interquartile range 24.0-25.3). Three subjects (5%) had an EEG change during the extended research EEG that resulted in a change in clinical management, including an increase in ES frequency, differential diagnosis of an event, and new interictal epileptiform discharges. No subjects had new-onset ES during the extended research EEG. No subjects experienced new-onset ES during the 24-hour extended research EEG period. This finding supports observational data that patients with late-onset ES are rare and suggests that ES prediction models derived from observational data are likely not substantially underrepresenting the incidence of late-onset ES after discontinuation of clinically indicated CEEG.

Information-based rhythmic transcranial magnetic stimulation to accelerate learning during auditory working memory training: a proof-of-concept study.

Rhythmic transcranial magnetic stimulation (rhTMS) has been shown to enhance auditory working memory manipulation, specifically by boosting theta oscillatory power in the dorsal auditory pathway during task performance. It remains unclear whether these enhancements (i) persist beyond the period of stimulation, (ii) if they can accelerate learning and (iii) if they would accumulate over several days of stimulation. In the present study, we investigated the lasting behavioral and electrophysiological effects of applying rhTMS over the left intraparietal sulcus (IPS) throughout the course of seven sessions of cognitive training on an auditory working memory task. A limited sample of 14 neurologically healthy participants took part in the training protocol with an auditory working memory task while being stimulated with either theta (5 Hz) rhTMS or sham TMS. Electroencephalography (EEG) was recorded before, throughout five training sessions and after the end of training to assess to effects of rhTMS on behavioral performance and on oscillatory entrainment of the dorsal auditory network. We show that this combined approach enhances theta oscillatory activity within the fronto-parietal network and causes improvements in auditoryworking memory performance. We show that compared to individuals who received sham stimulation, cognitive training can be accelerated when combined with optimized rhTMS, and that task performance benefits can outlast the training period by ∼ 3 days. Furthermore, we show that there is increased theta oscillatory power within the recruited dorsal auditory network during training, and that sustained EEG changes can be observed ∼ 3 days following stimulation. The present study, while underpowered for definitive statistical analyses, serves to improve our understanding of the causal dynamic interactions supporting auditory working memory. Our results constitute an important proof of concept for the potential translational impact of non-invasive brain stimulation protocols and provide preliminary data for developing optimized rhTMS and training protocols that could be implemented in clinical populations.

Pharmaco-EEG of antipsychotics’ response: a systematic review

IntroductionResponse to antipsychotic medications (AP) is subjected to a wide and unpredictable variability and efforts were directed to discover predictive biomarkers to personalize treatment. Electroencephalography abnormalities in subjects with schizophrenia were reported, as well as a pattern of EEG changes induced by APsObjectivesThe aim of this review is to provide a synthesis of the EEG features that are related to APs efficacy, including both pre-treatment signatures and changes induced by APs during treatment.MethodsA systematic review of English articles using PubMed, PsychINFO and the Cochrane database of systematic reviews was undertaken in april 2023. Additional studies were added by hand-search. Studies having as an endpoint the relationship between AP-related clinical improvement and electroencephalographic features were included. Heterogeneity prevented a quantitative synthesis.ResultsOut of 1232 records screened, 22 studies were included in a final qualitative synthesis. Included studies evaluated resting-state and task-related power spectra, functional connectivity, microstates and epileptic abnormalities. At pre-treatment EEG, the most relevant predictors of a poor response were a change in theta power compared to healthy control, a high alpha power and connectivity, a diminished beta power in resting-state. Considering EEG during treatment, an increased theta power, a reduced beta-band activity, an increased alpha activity, a decreased coherence in theta, alpha and beta-band were related to a favorable outcome.Conclusions EEG is promising as a method to create a predictive biomarker for response to APs; further investigations are warranted to harmonize and generalize the contradictory results of reviewed studies.Disclosure of InterestNone Declared

Gastric myoelectrical associations with autonomic and central nervous system activity during state negative emotionality and perseverative negative thinking: A two-study investigation

BackgroundDistress is known to set off a variety of physiological dysfunctions. There have been previous investigations of central and peripheral (e.g., cardiac) correlates of distress and a burgeoning field examining immunological and inflammatory relationships to distress. However, despite a connection between gastrointestinal symptoms and distress at the clinical level, little research has connected this activity to other biological correlates of distress. Heightened negative emotions and dysregulation of emotions in the form of perseverative negative thinking (PNT, e.g., worry, rumination) are two components that underlie distress. Investigating the effect that these components have on gastric and related biological measures is crucial to better understanding the relationship between distress and health outcomes. We present results from two studies, which examined the impact of experimentally induced negative emotionality and PNT on gastric, autonomic nervous system, central nervous system, and inflammatory processes. MethodIn Study 1 (N = 95), we examined changes in electrogastrogram (EGG), respiratory sinus arrythmia (RSA), and alpha- and beta-band electroencephalogram (EEG) power at baseline and during experimental inductions of fear and sadness in a diverse sample of undergraduate students. In Study 2 (N = 30), we examined changes in EGG, RSA, and EEG at baseline and during worry and rumination inductions. We also collected inflammatory markers post-inductions in Study 2. ResultsIn Study 1, normal gastric activity, vagal tone, and alpha- and beta-band power decreased, whereas EGG cycle length and variability increased during fear and sadness compared to baseline. We also observed significant relationships among EGG, RSA, and EEG during fear and sadness. In Study 2, normal gastric activity and RSA decreased, whereas EGG cycle length and variability increased during rumination compared to baseline. We also observed increases in frontal alpha-band power during worry and rumination compared to baseline. Regarding relationships among EGG, RSA, EEG, and inflammation, greater EGG cycle variability was associated with higher vagal tone during worry; additionally, EGG cycle length and variability during rumination were positively related to CRP and TNF-α inflammation composite scores post-inductions. ConclusionsThese findings offer insight into how negative emotionality and PNT might relate to gastric, ANS, CNS, and inflammatory processes.