Normalized Power Variance: A New Field Orthogonal to Power in EEG Analysis

To date, electroencephalogram (EEG) has been used in the diagnosis of epilepsy, dementia, and disturbance of consciousness via the inspection of EEG waves. In addition, EEG power analysis combined with a source estimation method like exact-low-resolution-brain-electromagnetic-tomography (eLORETA), which calculates the power of cortical electrical activity from EEG data, has been widely used to investigate cortical electrical activity in both healthy individuals and neuropsychiatric patients. However, the recently developed field of mathematics “information geometry” indicates that EEG has another dimension orthogonal to power dimension — that of normalized power variance (NPV). By also introducing the idea of information geometry, a significantly faster convergent estimator of NPV was obtained. In this study, we applied this NPV analysis of eLORETA to idiopathic normal pressure hydrocephalus (iNPH) patients prior to a cerebrospinal fluid (CSF) shunt operation, where traditional power analysis could not detect any difference associated with CSF shunt operation outcome. NPV analysis detected significantly higher NPV values at the high convexity area in the beta frequency band between 17 shunt responders and 19 non-responders. Our findings demonstrated that EEG has another dimension — that of NPV, which contains a great deal of information about cortical electrical activity that can be useful in clinical practice.

‘Fifth Day Fits’ (FDF) – Biotinidase Deficiency is Probably the New Name

Neonatal Seizures, the most critical of neonatal neurologic dysfunction, has aetiology of varying prognoses. The diagnosis of underlying aetiology is most critical. With use of genetic studies, better imaging technologies, better cortical electrical activity mapping and biochemical advancement, every attempt in diagnosing a cause is made.

An Investigation on the Electrical Activity of the Brain during Fara-Darmani Connection in the Fara-Therapist Population

Mind-body interaction and its manifestations at the brain level has been studied extensively in the field of consciousness research. Fara-darmani Consciousness Field, as claimed by Mohammad Ali Taheri (the founder), is a method of connecting with the Cosmic Consciousness Network through human mind and his brain has a detective role in this process. As a result of this connection, the scanning process of the state of a being, e.g., the health status of the cells and consequently organs is performed. This study was conducted to evaluate the effects of the Fara-darmani Consciousness Field connection on electroencephalogram (EEG) features as an important biomarker of the brain functioning. The results showed that there was a significant increase in the gamma2 frequency band (35-40 Hz) power in the frontal lobe in medial frontal gyrus (BA6) and paracentral lobule (BA31) of the brain during the task condition compared to the rest condition in a Fara-therapist population. Considering the cortical electrical activity of Fara-therapist’s brain during Fara-darmani Consciousness Field connection, characterizing increase in the power of gamma wave and the activity of the areas affecting on memory, attention, perception and default mode network intrinsic activity. This manifestation distinguishes Fara-darmani Consciousness Field connection from other known methods dealing with the mind-body interaction criterion mainly different types of mediation.

Peculiarities of brain processes during the stop and switch of motor programs among women

The purpose of the study is to establish differences in the cortical electrical activity among women under conditions of complete inhibition of a running motor program of manual movement (Stop-Signal paradigm) and under conditions of its inhibition, with subsequent switching to an alternative motor task (Stop-Change paradigm). We used the “event-related desynchronization/synchronization” (ERD/ERS) method. Indicators ERD and ERS were evaluated in the frequency range of EEG (1-35 Hz) in the frontal, central, and parietal leads. It was established that women demonstrated greater precision in conducting the task in the set with the Stop-Change paradigm than men. In both sets of the experiment, the predominance of ERS events in the range of α- and partially β1-activity of EEG is distinguished as a common regularity. Meanwhile, in different sets of the experiment, cortical electrical activity acquired certain specific features of the frequency-spatial organization that could indicate different brain processes during the response to Stop and Stop-Change stimuli. In the set of the use of the Stop-Change paradigm, a higher level of activation processes in the frontal, central, and parietal cortex areas in the EEG α- and β-activity range is generally showed among women.

Correlation Between Bispectral Index and Electrocorticographic Features During Epilepsy Surgery

Surgical resection guided by intraoperative electrocorticography (iECoG) has been in clinical use for many decades. The use of the bispectral index (BIS) for monitoring depth of anesthesia during different types of surgery, including epilepsy surgery, is increasing nowadays. The BIS is an EEG-derived variable indicating cortical electrical activity. However, the correlation between the BIS score and the iECoG score, with the purpose of optimizing the quality and time of the iECoG recordings in epilepsy surgery is unknown. The goal of this study was to evaluate the correlation between BIS values and iECoG parameters during the epilepsy surgery under anesthesia with propofol and fentanyl. This is a prospective study that included patients with epilepsy who underwent epilepsy surgery guided by BIS and iECoG (September 2008 to October 2013). Clinical, physiological, and sociodemographic characteristics are shown. We correlated the iECoG parameters (presence of burst suppressions [BS], suppression time [seconds], background frequency [Hz], and type of iECoG score by Mathern et al) with BIS values. We included 28 patients, 15/28 (53.5%) female, general mean age of 30.5 years (range 13-56 years). Patients underwent epilepsy surgery: 22/28 (79%) temporal and 6/28 (21%) extratemporal. We found a nonlinear polynomial cubic relationship between the mentioned variables noting that a BIS range of 40 to 60 gave the following results: iECoG BS periods <5 seconds, background frequency 10 to 17 Hz, and iECoG score 2 characterized by lack of >20-Hz background frequencies. No BS were observed with a BIS > 60. In conclusion BIS values and iECoG parameters during the epilepsy surgery under anesthesia with propofol and fentanyl have a nonlinear correlation. BS patterns were not found with a BIS > 60. These findings show that BIS is a nonlinear multidimensional measure, which possesses high variability with the iECoG parameters. BS patterns are not found with BIS > 60.

Evaluation of Cognitive Function in Migraine Patients

Cognitive impairments are observed in a portion of patients with migraines, but the underlying mechanisms for this impairment are not known. Event-related potentials (ERPs) have been recorded to clarify the mechanism, and the ERPs suggest that migraineurs exhibit exacerbated attention, executive dysfunction, and lack of habituation. Many factors, such as migraine phase, subtype, illness severity and duration, and preventive medicine use, are directly and indirectly involved in the cognitive function of migraine patients. Few reports have systematically considered these factors during the evaluation of cognitive function in migraine patients. In addition, the neuroanatomical basis for these cognitive dysfunctions is not clear. Recently, spatiotemporal analyses of ERPs using multichannel EEG recording have been developed, which might aid in the clarification of the relationships between cognitive dysfunction and the underlying neuropathological mechanisms. The relationships between the cortical electrical activity distribution of ERP components using standardized low-resolution brain electromagnetic tomography (sLORETA) and pathogenic factors were clarified in this study.