Electrophysiological and behavioral indicators of musical knowledge about unfamiliar music

Most listeners possess sophisticated knowledge about the music around them without being aware of it or its intricacies. Previous research shows that we develop such knowledge through exposure. This knowledge can then be assessed using behavioral and neurophysiological measures. It remains unknown however, which neurophysiological measures accompany the development of musical long-term knowledge. In this series of experiments, we first identified a potential ERP marker of musical long-term knowledge by comparing EEG activity following musically unexpected and expected tones within the context of known music (n = 30). We then validated the marker by showing that it does not differentiate between such tones within the context of unknown music (n = 34). In a third experiment, we exposed participants to unknown music (n = 40) and compared EEG data before and after exposure to explore effects of time. Although listeners’ behavior indicated musical long-term knowledge, we did not find any effects of time on the ERP marker. Instead, the relationship between behavioral and EEG data suggests musical long-term knowledge may have formed before we could confirm its presence through behavioral measures. Listeners are thus not only knowledgeable about music but seem to also be incredibly fast music learners.

Effects of the Essential Oils of Sweet Orange, Lavender and Amyris on EEG Activity

Purpose: This study evaluated the effects of the mixed essential oils containing sweet orange, lavender, and amyris (MEO) on human electroencephalogram (EEG) activity.Methods: EEG activity was recorded by examining the sequence of brain waves of 20 adults, aged from 20 to 30, before and during inhaling the mixed essential oils.Results: MEO showed activity centered on the frontal lobe, which is responsible for higher-order functions against external stimuli, and this result indicated that the oils acted as an intellectual effect. Additional experiments showed that the brain was relaxed and stabilized through a decrease in the absolute slow alpha (ASA) and the relative slow alpha (RSA), a decrease in the absolute beta (AB) and the absolute high beta (AHB), and an increase in the spectral edge frequency 50% of alpha (ASEF), respectively. Also, the oils induced the awakening states of the brain with a decrease in the absolute alpha (AA) and the absolute theta (AT), and increase of the spectral edge frequency 50% (SEF50). Furthermore, it was possible to confirm the state of brain immersion through the increase in the absolute fast alpha (AFA), relative fast alpha (RFA), relative mid beta (RMB), ratio of mid beta to theta (RMT), ratio of SMR to theta (RSMT), relative gamma (RG) and the spectral edge frequency 90% (SEF90).Conclusion: Taken together, these results suggest that the inhaling of MEO affect the brain to be a good condition and improves its concentration ability.

Analysis of Clinical Characteristics, Background, and Paroxysmal Activity in EEG of Patients with Juvenile Myoclonic Epilepsy

Juvenile myoclonic epilepsy (JME) appears in adolescence with myoclonic, absence, and generalized tonic clonic (GTC) seizures with paroxysmal activity of polyspike and slow wave (PSW), or spike and wave (SW) complexes in EEG. Our aim was to analyze the clinical characteristics, background EEG activity, and paroxysmal events in 41 patients with JME. Background EEG activity was analyzed with visual, quantitative (QEEG), and neurometric parameters. Our JME patients started with absence seizures at 11.4 ± 1.5 years old, myoclonic seizures at 13.6 ± 2.5 years, and GTC seizures at 15.1 ± 0.8 years. The seizures presented in awakening at 7:39 h with sleep deprivation, alcoholic beverage intake, and stress as the most frequent precipitant factors. Paroxysmal activity was of PSW and fast SW complexes with 40.5 ± 62.6 events/hour and a duration of 1.7 s. Right asymmetric paroxysmal activity was present in 68.3% of patients. Background EEG activity was abnormal in 31.7% of patients with visual analysis. With QEEG beta AP (absolute power) increase and AP delta decrease were the most frequent abnormalities found. Spectral analysis showed that 48.7% of patients had normal results, and 26.83% and 24.4% had higher and lower frequencies than 10.156 Hz, respectively. We concluded that, with visual analysis, background EEG activity was abnormal in a few patients and the abnormalities increased when QEEG was used.

Confirmatory Efficacy and Safety Trial of Magnetic Seizure Therapy for Depression (CREST-MST): protocol for identification of novel biomarkers via neurophysiology

Background Electroconvulsive therapy (ECT) is the most effective treatment for treatment-resistant depression (TRD), especially for acute suicidal ideation, but the associated cognitive adverse effects and negative stigma limit its use. Another seizure therapy under development is magnetic seizure therapy (MST), which could potentially overcome the restrictions associated with ECT with similar efficacy. The neurophysiological targets and mechanisms of seizure therapy, however, remain poorly understood. Methods/design This neurophysiological study protocol is published as a companion to the overall Confirmatory Efficacy and Safety Trial of Magnetic Seizure Therapy for Depression (CREST-MST) protocol that describes our two-site, double-blind, randomized, non-inferiority clinical trial to develop MST as an effective and safe treatment for TRD. Our aim for the neurophysiological component of the study is to evaluate two biomarkers, one to predict remission of suicidal ideation (primary outcome) and the other to predict cognitive impairment (secondary outcome). Suicidal ideation will be assessed through cortical inhibition, which according to our preliminary studies, correlates with remission of suicidal ideation. Cortical inhibition will be measured with simultaneous transcranial magnetic stimulation (TMS) and electroencephalography (EEG), TMS-EEG, which measures TMS-evoked EEG activity. Cognitive adverse effects associated with seizure therapy, on the contrary, will be evaluated via multiscale entropy analysis reflecting the complexity of ongoing resting-state EEG activity. Discussion ECT and MST are known to influence cortical inhibition associated with depression, suicidal ideation severity, and clinical outcome. Therefore, evaluating cortical inhibition and brain temporal dynamics will help understand the pathophysiology of depression and suicidal ideation and define new biological targets that could aid clinicians in diagnosing and selecting treatments. Resting-state EEG complexity was previously associated with the degree of cognitive side effects after a seizure therapy. This neurophysiological metric may help clinicians assess the risk for adverse effects caused by these useful and effective treatments. Trial registration ClinicalTrials.govNCT03191058. Registered on June 19, 2017.

Oscillatory electroencephalographic patterns of arithmetic problem solving in fourth graders

Numerous studies have identified neurophysiological correlates of performing arithmetic in adults. For example, oscillatory electroencephalographic (EEG) patterns associated with retrieval and procedural strategies are well established. Whereas fact retrieval has been linked to enhanced left-hemispheric theta ERS (event-related synchronization), procedural strategies are accompanied by increased bilateral alpha ERD (event-related desynchronization). It is currently not clear if these findings generalize to children. Our study is the first to investigate oscillatory EEG activity related to strategy use and arithmetic operations in children. We assessed ERD/ERS correlates of 31 children in fourth grade (aged between nine and ten years) during arithmetic problem solving. We presented multiplication and subtraction problems, which children solved with fact retrieval or a procedure. We analyzed these four problem categories (retrieved multiplications, retrieved subtractions, procedural multiplications, and procedural subtractions) in our study. In summary, we found similar strategy-related patterns to those reported in previous studies with adults. That is, retrieval problems elicited stronger left-hemispheric theta ERS and weaker alpha ERD as compared to procedural problems. Interestingly, we observed neurophysiological differences between multiplications and subtractions within retrieval problems. Although there were no response time or accuracy differences, retrieved multiplications were accompanied by larger theta ERS than retrieved subtractions. This finding could indicate that retrieval of multiplication and subtraction facts are distinct processes, and/or that multiplications are more frequently retrieved than subtractions in this age group.

Spectral Characteristics of EEG during Active Emotional Musical Performance

The research on neural correlates of intentional emotion communication by the music performer is still limited. In this study, we attempted to evaluate EEG patterns recorded from musicians who were instructed to perform a simple piano score while manipulating their manner of play to express specific contrasting emotions and self-rate the emotion they reflected on the scales of arousal and valence. In the emotional playing task, participants were instructed to improvise variations in a manner by which the targeted emotion is communicated. In contrast, in the neutral playing task, participants were asked to play the same piece precisely as written to obtain data for control over general patterns of motor and sensory activation during playing. The spectral analysis of the signal was applied as an initial step to be able to connect findings to the wider field of music-emotion research. The experimental contrast of emotional playing vs. neutral playing was employed to probe brain activity patterns differentially involved in distinct emotional states. The tasks of emotional and neutral playing differed considerably with respect to the state of intended-to-transfer emotion arousal and valence levels. The EEG activity differences were observed between distressed/excited and neutral/depressed/relaxed playing.