Single-trial extraction of event-related potentials (ERPs) and classification of visual stimuli by ensemble use of discrete wavelet transform with Huffman coding and machine learning techniques.

BACKGROUND: Presentation of visual stimuli can induce changes in EEG signals that are typically detectable by averaging together data from multiple trials for individual participant analysis as well as for groups or conditions analysis of multiple participants. This study proposes a new method based on the discrete wavelet transform with Huffman coding and machine learning for single-trial analysis of evenal (ERPs) and classification of different visual events in the visual object detection task. METHODS: EEG single trials are decomposed with discrete wavelet transform (DWT) up to the [Formula: see text] level of decomposition using a biorthogonal B-spline wavelet. The coefficients of DWT in each trial are thresholded to discard sparse wavelet coefficients, while the quality of the signal is well maintained. The remaining optimum coefficients in each trial are encoded into bitstreams using Huffman coding, and the codewords are represented as a feature of the ERP signal. The performance of this method is tested with real visual ERPs of sixty-eight subjects. RESULTS: The proposed method significantly discards the spontaneous EEG activity, extracts the single-trial visual ERPs, represents the ERP waveform into a compact bitstream as a feature, and achieves promising results in classifying the visual objects with classification performance metrics: accuracies 93.60[Formula: see text], sensitivities 93.55[Formula: see text], specificities 94.85[Formula: see text], precisions 92.50[Formula: see text], and area under the curve (AUC) 0.93[Formula: see text] using SVM and k-NN machine learning classifiers. CONCLUSION: The proposed method suggests that the joint use of discrete wavelet transform (DWT) with Huffman coding has the potential to efficiently extract ERPs from background EEG for studying evoked responses in single-trial ERPs and classifying visual stimuli. The proposed approach has O(N) time complexity and could be implemented in real-time systems, such as the brain-computer interface (BCI), where fast detection of mental events is desired to smoothly operate a machine with minds.

Transplantation of IGF-1-induced BMSC-derived NPCs promotes tissue repair and motor recovery in a rat spinal cord injury model.

Bone marrow-derived mesenchymal stem cells (BMSCs) have therapeutic potential for spinal cord injury (SCI). We have shown that insulin-like growth factor 1 (IGF-1) enhances the cellular proliferation and survivability of BMSCs-derived neural progenitor cells (NPCs) by downregulating miR-22-3p. However, the functional application of BMSCs-derived NPCs has not been investigated fully. In this study, we demonstrate that knockdown of endogenous miR-22-3p in BMSCs-derived NPCs upregulates Akt1 expression, leading to enhanced cellular proliferation. RNASeq analysis reveals 3,513 differentially expressed genes in NPCs. The upregulated genes in NPCs enrich the gene ontology term associated with nervous system development. Terminally differentiated NPCs generate cells with neuronal-like morphology and phenotypes. Transplantation of NPCs in the SCI rat model results in better recovery in locomotor and sensory functions 4 weeks after transplantation. Altogether, the result of this study demonstrate that NPCs derived with IGF-1 supplementation could be differentiated into functional neural lineage cells and are optimal for stem cell therapy in SCI.

A Comparative Study Across Methods to Identify Adolescents with Syntactic Specific Language Impairment.

Background: Specific language impairment (SLI) is described as a heterogeneous deficit that causes difficulties in various aspects of language. We performed a comparative study of two methods of language assessment with the primary objective of determining the most effective approach for identifying adolescents with syntactic SLI and typical development (TD) in use. Methods: A software-assisted method using E-Prime 2.0 was used to create an experiment. The participants were Malay adolescents aged 13 years old-15 years old. The conventional method was compared with the software-assisted method to assess the participants' comprehension and production performance. Data on reaction time (RT), scoring and no response (NR) were obtained from the adolescents. Results: Based on the two methods, the findings on the selection of participants for the SLI and TD groups was different. The two methods produced similar results in terms of the selection of TD group and most participants in the syntactic SLI group except for two participants who failed in the conventional method but passed the test in the software-assisted method. Conclusion: The descriptive evaluation of the findings suggested selecting software-assisted method as the alternative source because the provided information was detailed and this information enabled the researcher to identify the SLI group.

Post-Attentive Integration and Topographic Map Distribution During Audiovisual Processing in Dyslexia: A P300 Event-Related Component Analysis.

BACKGROUND: Research on audiovisual post-attentive integration has been carried out using a variety of experimental paradigms and experimental groups but not yet studied in dyslexia. We investigated post-attentive integration and topographic voltage distribution in children with dyslexia by analysing the P300 event-related potential (ERP) component. METHODS: We used a 128-child ERP net for the ERP experiment. Two types of stimuli were presented as either congruent or incongruent stimuli. Congruent stimuli included a matching auditory sound with an animal image, whereas incongruent stimuli included unmatched animal sounds. A total of 24 age-matched children were recruited in the control (n = 12) and dyslexia (n = 12) groups. Children pressed button '1' or '2' when presented with congruent or incongruent stimuli, respectively. The P300 amplitudes and latencies with topographic voltage distribution were analysed for both groups. RESULTS: The dyslexia group evoked significantly higher P300 amplitudes at the T4 area than the control group. No significant differences were found in cases of P300 latency. Moreover, the dyslexia group demonstrated a higher intensity of P300 voltage distribution in the right parietal and left occipital areas than the control group. CONCLUSION: Post-attentive integration for children with dyslexia is higher and that this integration process implicated the parietal and occipital areas.

Brain Tumours and Their Metabolic Profiles by Magnetic Resonance Spectroscopy

@#Introduction: Intracranial brain tumour like meningiomas and glioblastomas are most prevalent tumour. The metastasis to the brain is one of the major issues in the tumours of the central nervous system. The diagnosis of metastatic and primary brain tumour is incomprehensible with standard magnetic resonance imaging (MRI). The magnetic resonance spectroscopy (MRS) is basically performed in standard clinical setting for diagnosing and tracking the brain tumour. Method: It is a retrospective study containing 53 patients with MRS. The patients with metastatic tumour (n=10), glioblastomas (n=8) and meningiomas (n=20) are included in the study. Single voxel technique is applied in the tumour core to determine the metabolites. The tumour N-acetyl aspartate (NAA), Choline (Cho), Creatine (Cr), Lactate, Alanine and lipids were analysed. The ratios of NAA/Cr, Cho/NAA and Cho/Cr were recorded and compared between the three tumours. The metabolites were detected between short echo time (TE) to long echo time (TE) during MRS. Results: There is a sharp fall of NAA peak in metastatic tumour. The resonance of creatine, lactate and alanine is higher in glioblastomas. A high lipid mean value of 3.13(0.17) is seen in metastatic tumour. The ROC curve shows a low NAA/Cr specificity of 46.7%, high sensitivity of 83.3% in Cho/NAA and Cho/Cr ratio. Conclusion: The metabolic profiles of metastatic brain tumour, glioblastomas and meningioma illustrate a divergence in their description that will assist in planning therapeutic and surgical intervention of these tumours.

Euthymia in Diabetes: Clinical Evidence and Practice-Based Opinion from an International Expert Group.

AIM: To develop an evidence-based expert group opinion on various types of euthymia associated with diabetes mellitus (DM) and its management. BACKGROUND: Diabetes mellitus is a metabolic syndrome characterized by diverse biomedical and psychosocial features. Emotional health disturbances may lead to psychological and psychiatric dysfunction and may negatively influence glycemic control. Patients with DM may experience diabetes distress (DD) associated with burden of self-care, interpersonal issues, and emotional worries regarding the ability to cope with the illness. Euthymia or a state of positive mental health and psychological well-being should be considered a key outcome of diabetes care. Therefore, to achieve optimal outcomes, the consideration and measurement of psychological and psychiatric aspects along with glycemic levels are very important. A group of multidisciplinary clinical experts came together in an international meeting held in India to develop a workable concept for euthymia in diabetes care. A multidisciplinary approach was suggested to enhance the clinical outcomes and facilitate patient-centered care. During the meeting emphasis was given to the concept of a euthymia model in diabetes care. This model focuses on enhancement of self-care skills in diabetic patients and preventative health awareness among diabetes care providers. Euthymia also encompasses patient-provider communication to aid enhancement of coping skills. RESULTS: After due discussions and extensive deliberations, the expert group provided several recommendations on implementing the concept of euthymia in DM care. CONCLUSIONS: Introduction of the concept of euthymia in routine clinical practice is important to improve the quality of life and coping skills in patients with DM. A timely clinical assessment of psychological and psychiatric aspects along with patient-reported outcomes of diabetes contributes to overall health and well-being of affected individuals. FUNDING: Sanofi India.

Hippocampal amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid GluA1 (AMPA GluA1) receptor subunit involves in learning and memory improvement following treatment with Centella asiatica extract in adolescent rats.

INTRODUCTION: Centella asiatica is an herbal plant that contains phytochemicals that are widely believed to have positive effects on cognitive function. The adolescent stage is a critical development period for the maturation of brain processes that encompass changes in physical and psychological systems. However, the effect of C. asiatica has not been extensively studied in adolescents. The aim of this study was therefore to investigate the effects of a C. asiatica extract on the enhancement of learning and memory in adolescent rats. METHODS: The locomotor activity, learning, and memory were assessed by using open field test and water T-maze test. This study also examined changes in neuronal cell morphology using cresyl violet and apoptosis staining. We also performed immunohistochemical study to analyse the expression of the glutamate AMPA receptor (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) GluA1 subunit and the GABA receptor (γ-Aminobutyric Acid) subtype GABAA α1 subunit in the hippocampus of the same animals. RESULTS: We found no significant changes in locomotor activity (p > 0.05). The water T-maze data showed that 30 mg/kg dose significantly (p < 0.05) improved learning, memory, and the memory consolidation phase but had no effect on reversal learning (p > 0.05). Histological data revealed no neuronal morphological changes. Immunohistochemical analysis revealed increased expression of the AMPA GluA1 receptor subunit but there was no effect on GABAA receptor α1 subunit expression in the CA1 and CA2 subregions of the hippocampus. CONCLUSIONS: The C. asiatica extract therefore improved hippocampus-dependent spatial learning and memory in a dose-dependent manner in rats through the GluA1-containing AMPA receptor in the CA1 and CA2 sub regions of the hippocampus.

The Effect of Sex on the Electropsychological Process of Emotional Arousal Intensity.

BACKGROUND: Sex is a psychobiological factor that is important in the process of emotion. This study determines the effect of sex on the electropsychological process of various intensities of emotional arousal. METHODS: In the Event-related Potential (ERP) session, electroencephalographic (EEG) data was recorded for 90 participants, 60% of whom were females. The participants responded to 30 universal emotional pictures, randomly chosen from the International Affective Picture System (IAPS), which were classified as invoking high, moderate, and low intensity of emotional arousal. RESULTS: From the analysis of variance of two-way mixed design, the interaction between sex and emotional intensity was observed in the occipital regions (O2), indexed by the amplitude of P300 and N200 components. Males exhibited higher amplitude of P300 and N200 components (in the occipital region) as responded to high and low emotional arousal stimuli than females. CONCLUSION: Sex is a fundamental factor that modulates psychological states in reaction to emotional stimuli.

The Effect of Sex on the Electropsychological Process of Emotional Arousal Intensity

Background: Sex is a psychobiological factor that is important in the process of emotion.This study determines the effect of sex on the electropsychological process of various intensities ofemotional arousal.Methods: In the Event-related Potential (ERP) session, electroencephalographic (EEG)data was recorded for 90 participants, 60% of whom were females. The participants responded to30 universal emotional pictures, randomly chosen from the International Affective Picture System(IAPS), which were classified as invoking high, moderate, and low intensity of emotional arousal.Results: From the analysis of variance of two-way mixed design, the interaction betweensex and emotional intensity was observed in the occipital regions (O2), indexed by the amplitudeof P300 and N200 components. Males exhibited higher amplitude of P300 and N200 components(in the occipital region) as responded to high and low emotional arousal stimuli than females.Conclusion: Sex is a fundamental factor that modulates psychological states in reaction toemotional stimuli.

Observation of Auditory Perceptual and Visuo-Spatial Characteristic of a Patient with Hemangiopericytoma in Occipital Lobe: A Magnetoencephalography (MEG) Study / Jurnal Sains Kesihatan Malaysia

@#The present study discussed functional reorganization and alteration in respond to the slow-growing tumour,hemangiopericytoma in the occipital cortex. Visual evoked field (VEF) and auditory evoked field (AEF) usingmagnetoencephalography (MEG) was used to evaluate the source localization and brain activity. Results of VEF sourcelocalization show a typical brain waves. Brain activity of the occipital lobe demonstrate low activation in the ipsilateralto the tumour. However, result shows the activation on the contralateral hemisphere was high and bigger in activationvolume. AEF result shows an identical source localization and both side of the temporal lobe are activated. This resultsuggests that there is a positive plasticity in auditory cortex and slow-growing tumour can induce functional reorganizationand alteration to the brain.

Assessing Neuroplasticity Using Magnetoencephalography (MEG) in Patient with Left-Temporo-Parietal Pilocytic Astrocytomas Treated with Endoscopic Surgery / Jurnal Sains Kesihatan Malaysia

@#Neuroplasticity has been subjected to a great deal of research in the last century. Recently, significant emphasis has beenplaced on the global effect of localized plastic changes throughout the central nervous system, and on how these changesintegrate in a pathological context. The present study aimed to demonstrate the functional cortical reorganization beforeand after surgery using magnetoencephalography (MEG) in a participant with brain tumor. Results of Visual EvokedMagnetic Field (VEF) based on functional MEG study revealed significantly different of MEG N100 waveforms before andafter surgery. Larger and additional new locations for visual activation areas after the surgery were found suggestingneuroplasticity. The present study highlight a physiological plasticity in a teenage brain and the alterations regardingneural plasticity and network remodeling described in pathological contexts in higher-order visual association areas.

How Much We Think of Ourselves and How Little We Think of Others: An Investigation of the Neuronal Signature of Self-Consciousness between Different Personality Traits through an Event-Related Potential Study.

BACKGROUND: Previous studies have revealed that self-related tasks (items) receive more attention than non-self-related, and that they elicit event-related potential (ERP) components with larger amplitudes. Since personality has been reported as one of the biological correlates influencing these components, as well as our behavioural differences, it is important to examine how it affects our self-consciousness in relation to tasks of varied relevance and the neurological basis. METHODS: A total of 33 male and female undergraduate Malaysian medical students of Universiti Sains Malaysia (USM) participated in the study. The participants were divided into two groups, Ambivert (n = 18) and Extravert (n = 15) groups, using the USM personality inventory questionnaire. In the ERP experiment, squares containing standard stimuli of any word other than self and non-self-related nouns (e.g., Bola, Gigi, Anak, etc.; in English: Ball, Teeth, Kids, etc., respectively), those containing self-related pronouns (Saya, Kami or Kita; in English: I, Us or We, respectively), and non-self-related pronouns (Dia, Anda or Mereka; in English: He/She, You or They, respectively), were shown 58%, 21% and 21% of the time, respectively, in a three-stimulus visual oddball paradigm. All words were presented in Bahasa Melayu. The participants were instructed to press 1 for self and 2 for non-self, and ignore standard stimuli. RESULTS: Comparison of both N200 and P300 amplitudes for self-related and non-self-related pronouns in the Extravert group revealed significant differences at seven electrode sites, with self-related having larger amplitude at anterior electrodes and less at posterior. This was not seen in the Ambivert group. CONCLUSION: The present study suggests that self-relevant pronouns are psychologically more important to extraverts than to ambiverts; hence, they have more self-awareness. This may be due to large amount of dopamine in the brains of extraverts, which is more concentrated in the frontal lobe.

How Much We Think of Ourselves and How Little We Think of Others: An Investigation of the Neuronal Signature of Self-Consciousness between Different Personality Traits through an Event-Related Potential Study

Background: Previous studies have revealed that self-related tasks (items) receive more attention than non-self-related, and that they elicit event-related potential (ERP) components with larger amplitudes. Since personality has been reported as one of the biological correlates influencing these components, as well as our behavioural differences, it is important to examine how it affects our self-consciousness in relation to tasks of varied relevance and the neurological basis. Methods: A total of 33 male and female undergraduate Malaysian medical students of Universiti Sains Malaysia (USM) participated in the study. The participants were divided into two groups, Ambivert (n = 18) and Extravert (n = 15) groups, using the USM personality inventory questionnaire. In the ERP experiment, squares containing standard stimuli of any word other than self and non-self-related nouns (e.g., Bola, Gigi, Anak, etc.; in English: Ball, Teeth, Kids, etc., respectively), those containing self-related pronouns (Saya, Kami or Kita; in English: I, Us or We, respectively), and non-self-related pronouns (Dia, Anda or Mereka; in English: He/She, You or They, respectively), were shown 58%, 21% and 21% of the time, respectively, in a three-stimulus visual oddball paradigm. All words were presented in Bahasa Melayu. The participants were instructed to press 1 for self and 2 for non-self, and ignore standard stimuli. Results: Comparison of both N200 and P300 amplitudes for self-related and non-selfrelated pronouns in the Extravert group revealed significant differences at seven electrode sites, with self-related having larger amplitude at anterior electrodes and less at posterior. This was not seen in the Ambivert group. Conclusion: The present study suggests that self-relevant pronouns are psychologically more important to extraverts than to ambiverts; hence, they have more self-awareness. This may be due to large amount of dopamine in the brains of extraverts, which is more concentrated in the frontal lobe.

Candidate gene approach for parasite resistance in sheep--variation in immune pathway genes and association with fecal egg count.

Sheep chromosome 3 (Oar3) has the largest number of QTLs reported to be significantly associated with resistance to gastro-intestinal nematodes. This study aimed to identify single nucleotide polymorphisms (SNPs) within candidate genes located in sheep chromosome 3 as well as genes involved in major immune pathways. A total of 41 SNPs were identified across 38 candidate genes in a panel of unrelated sheep and genotyped in 713 animals belonging to 22 breeds across Asia, Europe and South America. The variations and evolution of immune pathway genes were assessed in sheep populations across these macro-environmental regions that significantly differ in the diversity and load of pathogens. The mean minor allele frequency (MAF) did not vary between Asian and European sheep reflecting the absence of ascertainment bias. Phylogenetic analysis revealed two major clusters with most of South Asian, South East Asian and South West Asian breeds clustering together while European and South American sheep breeds clustered together distinctly. Analysis of molecular variance revealed strong phylogeographic structure at loci located in immune pathway genes, unlike microsatellite and genome wide SNP markers. To understand the influence of natural selection processes, SNP loci located in chromosome 3 were utilized to reconstruct haplotypes, the diversity of which showed significant deviations from selective neutrality. Reduced Median network of reconstructed haplotypes showed balancing selection in force at these loci. Preliminary association of SNP genotypes with phenotypes recorded 42 days post challenge revealed significant differences (P<0.05) in fecal egg count, body weight change and packed cell volume at two, four and six SNP loci respectively. In conclusion, the present study reports strong phylogeographic structure and balancing selection operating at SNP loci located within immune pathway genes. Further, SNP loci identified in the study were found to have potential for future large scale association studies in naturally exposed sheep populations.

N200 latency and P300 amplitude in depressed mood post-traumatic brain injury patients.

In order to examine the independent and combined effects of depressive symptoms and traumatic brain injury on event-related potential (ERP) components, we classified traumatic brain injury (TBI) patients as depressed and non-depressed mood according to their scores on the Zung Self-rating Depression Scale (SDS). Non-depressed mood post-traumatic brain injury patients (NondepTBI, n=9), depressed mood post-traumatic brain injury patients (DepTBI, n=26), and normal healthy control subjects (HC, n=10) were assessed for N100, N200, and P300 latencies and amplitudes by the auditory "oddball paradigm". DepTBI subjects had significantly prolonged N200 latency and low P300 amplitude compared with the NondepTBI and HC groups. A longer P300 latency in the NondepTBI and DepTBI than in the HC groups was found. A prolongation of N200 latency accompanied by low P300 amplitude may be a characteristic of post-traumatic brain injury patients with depressed mood. Prolonged P300 latency may be more closely associated with TBI than with depression, as it was significantly greater in both the DepTBI and NondepTBI, than in the HC group.

Mechanomyographic response to transcranial magnetic stimulation from biceps brachii and during transcutaneous electrical nerve stimulation on extensor carpi radialis.

Transcranial magnetic stimulation (TMS) elicits short latency excitatory responses in the target muscles, termed motor evoked potential (MEP). When TMS is delivered during a voluntary contraction, the MEP is followed by a period of silence called silent period (SP). These MEP parameters are in general recordable by electromyography (EMG). Mechanomyography (MMG) on the other hand is the mechanical counterpart of EMG. Thus, this study has been conducted to observe whether the MEP parameters from MMG signals showed similar trait of EMG recordings. Five normal healthy male subjects were included in this study. The subjects were required to perform right biceps brachii muscles contraction at diverse graded of load level at 5, 10, 20, 30, 40, 60, and 100% maximum voluntary contraction (MVC). MEPs by single pulse TMS on left hemisphere were obtained from both EMG electrode and MMG accelerometer at rest and at different levels of predetermined load level. MEP amplitude and area obtained both from EMG and MMG record were increased with the increase of muscle contraction with a maximum of 60% MVC. With increasing the level of contraction there was a shortening of onset latency and decreasing in the length of silent period in both EMG and MMG signals. We also recorded the EMG- and MMG-MEP from the right extensor carpi radialis muscle during transcutaneous electric nerve stimulation in order to observe neural changes in sensory stimulation from both EMG and MMG responses. The EMG-MEP was not visible in electrical artifact whereas it was obvious in MMG responses. In accordance with other study, this study showed that the voluntary contraction of biceps brachii muscle influenced the MEP parameter which are moreover obtainable by MMG even in electrical noise may provide insight for future study.

Evaluation of a new physical exercise taken from salat (prayer) as a short-duration and frequent physical activity in the rehabilitation of geriatric and disabled patients.

BACKGROUND: The major function of rehabilitation and physical medicine specialists is to provide the proper therapy that helps in improving the physical activities of impaired, disabled and handicapped persons through improvement in their muscle strength. In performing their function, the rehabilitation team should always take heed of the social and mental well-being of such patients. Having observed millions of Muslims perform the salat (prayer) regularly at specified times throughout the world, we postulated that salat, along with its various postures, can play a role in increasing psychological well-being including self-reliance and self-esteem, improving musculo-skeletal fitness, motor behavior and cerebral blood flow that may be beneficial in the rehabilitation of geriatric and disabled persons. SUBJECTS AND METHODS: The various postures of salat were studied and a range of joint motions were measured by goniometer, an instrument for measuring angles. Brain blood pressure was calculated from the effect of gravity on blood pressure at different positions. RESULTS: We found that during the offering of salat, most of the joints and muscles of the body were involved in physical activities with little effort, which probably play a vital role in cerebral blood flow and postural reflexes. CONCLUSION: The physical activities involved in the performance of salat helps in the rehabilitation process in disabled geriatric patients by improving blood flow and increasing musculoskeletal fitness. The salat prayer involves little effort (standing, bowing, prostration and sitting), has a short duration and is beneficial for mental and physical health. More studies are needed in future to determine the full beneficial effects of the salat prayer on the rehabilitative process of disabled persons.