Detección de novedad y codificación predictiva en el sistema auditivo: Impacto clínico en disfunciones auditivas y vestibulares. Revisión de la literatura / Deviance detection and predictive coding in the auditory system: Clinical impact in auditory and vestibular dysfunctions

Una propiedad fundamental de los sistemas sensoriales es su capacidad para detectar estímulos novedosos en el entorno. El sistema nervioso posee neuronas que disminuyen su respuesta a los estímulos sonoros que se repiten a lo largo del tiempo y otras neuronas que aumentan su frecuencia de disparo ante estímulos novedosos, siendo la diferencia entre ambas respuestas conocida como adaptación-específica a estímulos. En las últimas décadas, se ha propuesto que el cerebro establece, continuamente, predicciones de los estímulos novedosos y del entorno basándose en sus experiencias previas y en modelos de representación internos, teoría denominada codificación predictiva. En esta revisión, abordaremos algunos conceptos de la adaptación-específica a estímulos y codificación predictiva, centrándonos principalmente en el sistema auditivo. Por último, propondremos una explicación teórica basada en el marco de la codificación predictiva para algunas disfunciones neuropsiquiátricas, auditivas y vestibulares.

A fundamental property of sensory systems is their ability to detect novel stimuli in the environment. The nervous system possesses neurons that decrease their response to sound stimuli that are repeated over time and other neurons that increase their firing rate to novel stimuli, the difference between the two responses being known as stimulus-specific adaptation. In recent decades, it has been proposed that the brain continuously makes predictions of novel stimuli and the environment based on its previous experiences and internal representational models, a theory called predictive coding. In this review, we will address some concepts of stimulus-specific adaptation and predictive coding, focusing mainly on the auditory system. Finally, we will propose a theoretical explanation based on the predictive coding framework for some neuropsychiatric, auditory, and vestibular dysfunctions.

Auditory mismatch negativity in attention deficit hyperactivity disorder in children： a Meta-analysis / 四川精神卫生

ObjectiveTo explore the differences existing in the auditory mismatch negativity （MMN） amplitude and latency between children with attention deficit hyperactivity disorder （ADHD） and normal children， and to probe into the significance of MMN latency and amplitude for assessing the auditory perception and attention level in ADHD children and normal children. MethodsOn December 1， 2022， a systematic search was performed in PubMed， Embase， Cochrane Library， China National knowledge Infrastructure （CNKI）， Wanfang Data Knowledge Service Platform and VIP databases to identify all well qualified literature focusing on MMN of ADHD children， then the valid data relevant to MMN amplitude and latency were extracted. The Newcastle-Ottawa Scale （NOS） was used to assess the quality of the included studies， and Stata 20.0 was employed for Meta-analysis. ResultsA total of 9 qualified studies comparing ADHD children （n=170） against healthy controls （n=159） were finally included. Among the included literature， there were 18 matched pairs of MMN amplitude data and 10 matched pairs of MMN latency data at different recording sites. Meta-analysis denoted that ADHD group resulted in potentials of slightly lower MMN amplitude （WMD=-0.334， 95% CI： -1.426~0.758， P=0.549） and notably longer MMN latency （WMD=14.768， 95% CI： 4.660~24.876， P=0.004） compared to control group， and the Bgger's funnel plot did not reveal any publication bias. ConclusionCompared with healthy controls， ADHD children have longer MMN latency， suggesting that the auditory perception and attention level of ADHD children may be reduced.

Potencial de disparidad o Mismatch negativity y P3a en pacientes con esquizofrenia / Mismatch negativity and P3a in patients with Schizophrenia

Resumen Antecedentes: la esquizofrenia es una enfermedad crónica que genera gran discapacidad, para la cual se han reportado biomarcadores potenciales, pero sin suficiente validez clínica. El mismatch negativity (MMN) y el P3a son potenciales relacionados con eventos que han demostrado ser indicadores neurofisiológicos del procesamiento auditivo pre-atencional y potenciales biomarcadores. Objetivo: evaluar el MMN y P3a en pacientes con diagnóstico de esquizofrenia y su relación con variables sociodemográficas y clínicas. Método: estudio cuantitativo transversal de 23 sujetos con esquizofrenia (ESQ) y 22 controles sanos (SN). Las amplitudes promedio y latencias del MMN/P3a para la condición infrecuente en duración y frecuencia fueron obtenidas mediante un paradigma oddball auditivo en un EEG de 32 canales. Resultados: se encontraron diferencias para la condición frecuencia en la amplitud del MMN (p=0.046; CI 95% 0.009; 0.87) y la amplitud del P3a (p=0.042; CI 95% 0.025; 1.24) entre los grupos; la amplitud del MMN fue menor en el grupo ESQ (-0.36 DE 0.51 µV) en comparación con los participantes del grupo de SN (-0.81 DE 0.89 µV), mientras que la amplitud del P3a fue menor en el grupo SN (0.18 DE 0.97 µV) versus el grupo ESQ (0.82 DE 1.05 µV). En relación con las variables sociodemográficas y clínicas, las asociaciones con el P3a fueron moderadas y con el MMN débiles. Conclusiones: la reducción de la amplitud del MMN a la condición frecuencia exhibe mayor utilidad que el P3a como medida de alta estabilidad en pacientes con esquizofrenia, lo que reitera su posible uso como biomarcador.

Abstract Background: schizophrenia is a chronic disease that generates great disability, which currently has potential biomarkers but without sufficient clinical validity. Mismatch negativity (MMN) and P3a are event-related potentials that have been shown to be neurophysiological indicators of pre-attentional auditory processing and potential biomarkers. Objective: to evaluate MMN and P3a in patients with a diagnosis of schizophrenia and their relationship with sociodemographic and clinical variables. Method: a quantitative cross-sectional study of 23 subjects with schizophrenia and 22 healthy controls was performed. The average amplitudes and latencies of the MMN/P3a for the condition infrequent in duration and infrequent in frequency were obtained using an auditory oddball paradigm on a 32-channel EEG. Results: differences were found for the frequency condition in the amplitude of the MMN (p=0.046; 95% CI 0.009; 0.87) and the amplitude of the P3a (p=0.042; 95% CI 0.025; 1.24) between the groups; MMN amplitude was lower in schizophrenia (-0.36 SD 0.51 µV) compared to healthy controls (-0.81 SD 0.89 µV), while P3a amplitude was lower in healthy controls (0.18 SD 0.97 µV) versus the group with schizophrenia (0.82 SD 1.05 µV). In regard to sociodemographic and clinical variables, the associations with P3a were moderate, and showed weak MMN. Conclusions: MMN amplitude reduction to the frequency condition exhibits greater utility than P3a as a measure of high stability in schizophrenia, restating its potential use as a biomarker.

Does mismatch negativity have utility for NMDA receptor drug development in depression?

Rapid antidepressant effects associated with ketamine have shifted the landscape for the development of therapeutics to treat major depressive disorder (MDD) from a monoaminergic to glutamatergic model. Treatment with ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, may be effective, but has many non-glutamatergic targets, and clinical and logistical problems are potential challenges. These factors underscore the importance of manipulations of binding mechanics to produce antidepressant effects without concomitant clinical side effects. This will require identification of efficient biomarkers to monitor target engagement. The mismatch negativity (MMN) is a widely used electrophysiological signature linked to the activity of NMDA receptors (NMDAR) in humans and animals and validated in pre-clinical and clinical studies of ketamine. In this review, we explore the flexibility of the MMN and its capabilities for reliable use in drug development for NMDAR antagonists in MDD. We supplement this with findings from our own research with three distinct NMDAR antagonists. The research described illustrates that there are important distinctions between the mechanisms of NMDAR antagonism, which are further crystallized when considering the paradigm used to study the MMN. We conclude that the lack of standardized methodology currently prevents MMN from being ready for common use in drug discovery. Clinical trial registration: This manuscript describes data collected from the following National Institutes of Health (NIH) and Veterans Affairs (VA) studies: AV-101, NCT03583554; lanicemine, NCT03166501; ketamine, NCT02556606.

Research and Prospect of Visual Event-Related Potential in Traumatic Brain Injury and Visual Function Evaluation / 法医学杂志

Visual event-related potential (ERP) is an electrophysiological technique that objectively reflects the cognitive processing of stimulus from the perspective of detecting and recording neural electrophysiology responses using different paradigms of visual stimuli. Its endogenous components are closely related to advanced psychological activities. This article introduces the characteristics of main endogenous components including visual mismatch negativity (vMMN), N200 and P300, reviews the research progress of visual ERP in the sequelae of brain injury and objective evaluation of visual function, and prospects the application prospect of visual ERP in the field of forensic medicine.

Pre-attentive processing in autism spectrum disorder / 中华行为医学与脑科学杂志

Autism spectrum disorder (ASD) is a neurodevelopmental disorder.Its typical symptoms include social disorder, stereotyped behavior and restrictive interest.In addition, sensory abnormality is also a common symptom of ASD individuals.Pre-attentive processing is an automatic cognitive process that takes place before attention and is independent of consciousness, which reflects the ability to automatically detect changes in the environment of brain.Many researches show that the sensory abnormality and social ability disorder in ASD patients may be related to the defects in the pre-attentive processing stage.Mismatch negativity (MMN) is the most commonly used indicator of pre-attentive processing.ASD individuals show abnormal MMN in response to both social and non-social stimulus.Among them, the pre-attentive processing defect of non-social stimuli in ASD individuals is manifested as the amplitude or latency of MMN induced by single tones, voice or visual stimuli, which is different from that of normal people.The pre-attentive processing defect of social stimuli in ASD individuals is manifested as the amplitude or latency of MMN induced by emotional voice and emotional face, which is different from that of normal people.This result not only helps to find the physiological mechanism of sensory and social disorders in ASD individuals, but also provides theoretical support for MMN as an auxiliary diagnostic index of ASD.Future research on the pre-attentive processing of ASD individuals should pay more attention to enriching the research paradigms of MMN and adopting more kinds of social stimuli.At the same time, the influence of ASD genetic factors on MMN can also be one of the concerns of future research.

Effects of Electroacupuncture on Consciousness Disorders Based on Transcranial Magnetic Stimulation: Study with Mismatch Negativity / 中国康复理论与实践

Objective:To observe the effect of electroacupuncture based on transcranial magnetic stimulation (TMS) on wakefulness for consciousness disorder. Methods:From January, 2015 to October, 2019, 30 inpatients with consciousness disorder from the General Hospital of Western Theater Command were randomly divided into control group (n = 15) and observetion group (n = 15), Both groups received TMS, and the observetion group received electroacupuncture at Baihui (GV20), Shenting (GV24), bilateral Neiguan (PC6) bilateral Hegu (LI4) and bilateral Yongquan (KI1) in addition, for three months. They were tested the latency of the mismatch negativity (MMN), and assessed with Glasgow Coma Scale (GCS) and persistent vegetative state (PVS) score before, and one month and three months after treatment. Results:The latency of MMN decreased more in the observetion group than in the control group three months after treatment (t = 2.159, P < 0.05). Conclusion:Combination of electroacupuncture on TMS is more effective on wakefulness for consciousness disorder.

The clinical efficacy of treating autistic children using transcranial direct current stimulation / 中华物理医学与康复杂志

Objective:To investigate the effect of transcranial direct current stimulation (tDCS) on the behavior and the mismatch negativity (MMN) component of the auditory evoked potential of autistic children.Methods:Thirty-four autistic children were randomly divided into an anode stimulation group ( n=19) and a pseudo-stimulation group ( n=16). Both groups were given one hour of routine rehabilitation five times a week for 4 weeks, while the anode stimulation group was additionally provided with 20 minutes of tDCS 3 times a week. Before and after the treatment, both groups′ behavior was evaluated by using autism behavior checklist (ABC) as well as any changes in MMN of the auditory evoked EEG signals. Results:There were no significant differences between the two groups in any of the measurements before the treatment. Afterwards behavior had improved significantly in both groups, with significantly greater improvement in the stimulated group. In the stimulated group the average MMN amplitude had increased significantly and the average latency had decreased significantly. However, no such significant changes were observed in the pseudo-stimulation group. There was a significant linear correlation between the changes in the incubation period of MMN components and the improvements in ABC, vestibular functioning, tactile defense and proprioception.Conclusion:Anodal tDCS combined with conventional rehabilitation therapy can effectively increase the MMN amplitude and shorten the latency in autistic children, improving their brain function.

Hepatitis B virus infection confirmation and infection status identification in blood donors without serological markers / 中国输血杂志

【Objective】 To confirm Hepatitis B virus (HBV) infections and identify infection status by excluding false positive in blood donors reactive to nucleic acid testing (NAT) but without serological markers (Seroneg-NAT). 【Methods】 Seroneg-NAT yields were selected among blood donors in Dalian Blood Center from November 1, 2010 to February 28, 2021, and their HBV DNA was further confirmed with TaqMan HBV DNA quantification or virions concentration by polyethylene glycol (PEG) precipitation combined with in-house nested PCR targeting the S, BCP, PreS/S and Precore/core regions of the viral genome, and follow-up test was carried out, including blood routine screening and HBsAg, anti-HBs and anti-HBc testing. HBV infection was confirmed by HBV DNA yielding and anti-HBs/anti-HBc seroconversion in follow-up testing, and HBV DNA was further sequenced if necessary. 【Results】 During the period of 10 years and 4 months, 0.03% (126/466 911) Seroneg-NAT yields were selected, of which 46.8% (59/126) were HBV DNA+ and 53.2% (67/126) were unconfirmed. Among 126 Seroneg-NAT yields, 40.5% (51/126) were involved in follow-up test, of which 28 were HBV DNA+ and 23 were unconfirmed. HBV infections were confirmed in 48% (60/126) of Seroneg-NAT yields. Of follow-up donors, 54.9% (28/51) were identified as early infection before seroconversion, 2.0% (1/51) seronegative occult HBV infection (OBI), and 37.3% (19/51) NAT false positive. There were still 5.9% (3/51) classified as the indetermination. 【Conclusion】 Nearly half Seroneg-NAT yields in Dalian blood donors were infected with HBV and more than 50% were early infections before seroconversion. The majority of HBV DNA unconfirmed without serological markers were false positives.

Pontes sobre o nada: narrativas do sofrimento e transformação existencial / Bridges over nothingness: narratives of suffering and existential transformation

O principal intuito do presente artigo é questionar uma tendência estrutural de nosso modo tradicional de compreensão do problema da negatividade. Se considerarmos a reação imediata à afirmação de que a existência se caracteriza exatamente como uma indeterminação ontológica radical, não é incomum perceber a dificuldade de assumir essa afirmação sem uma certa sensação de que inviabiliza por completo a própria existência, caso não seja contrabalanceada por alguma dimensão de soterramento da nadidade, de pavimentação da negatividade. Tal dificuldade repercute sobre os modos mais imediatos de lidar com o sofrimento existencial e mesmo de pensar o foco mais essencial das terapias em geral. Na medida em que questionamos esses modos e seus pressupostos mais imediatos, o que buscamos aqui é antes de tudo investigar até que ponto o problema mais intrínseco do sofrimento reside precisamente na carga imensa que provém justamente da tentativa de fugir dele. Heidegger é, nesse contexto, nosso parceiro mais próximo de diálogo, assim como a metáfora da ponte e do farol que nos guia incessantemente em nosso caminho.

The central aim of the present article is to put in question a structural tendency of our tradition of understanding the problem of negativity. If we consider the immediate reaction to the assertion that existence characterizes itself exactly through a very ontological indeterminacy, it is not uncommon to perceive how hard is to embrace this assertion without a sensation that it makes impossible the own existence, if it is not counterbalanced by any kind of attenuation to such a nothingness, of paving negativity. Such difficulty resonates over the main ways to cope with existential suffering and even of thinking the most essential focus of therapies in general. Putting in question these ways of thinking and their presupposes, we are trying over all to investigate if suffering itself has its basis in the extraordinary weight arousing from the proper attempt to avoid suffering. Heidegger is, in this context, our closer partner of dialog, such as the metaphors of the bridge and the lighthouse which guide us in our path.

Sartre por Barbaras: movimentos de uma leitura crítica / Sartre by Barbaras: movements of a critical reading / Sartre por Barbaras: movimientos de una lectura crítica

Neste trabalho nos propomos a apresentar alguns movimentos da leitura crítica que Renaud Barbaras realiza da filosofia de Sartre. Para tal, escolhemos como fio condutor a retomada que este autor faz do dualismo de base da filosofia sartriana, em continuidade com a crítica de Merleau-Ponty, porém de modo a abrir outros caminhos de reflexão. Gostaríamos de evidenciar nestes caminhos o quanto Barbaras não somente potencializa a crítica precedente, mas realiza aproximações e problematizações originais que, ao mesmo tempo em que tornam mais evidentes os impasses da filosofia sartriana, não deixam de abrir novas possibilidades de investigação. Estas últimas nuances serão apontadas através da crítica propriamente barbarasiana da questão do outro e do desejo em Sartre.

In this work we propose to present some movements of the critical reading that Renaud Barbaras performs of Sartre's philosophy. For this, we have chosen as the guiding thread the author's reiteration of the basic dualism of Sartre's philosophy, in alignment with Merleau-Ponty's critique, but seeking to open other paths of reflection. We would like to point out in these paths that not only does Barbaras enhance the preceding critiques, but makes original approaches and problematizations, which makes the impasses of Sartre's philosophy more evident while also opening new possibilities for investigation. These later nuances will be pointed out through a properly Barbarasian critique of the question of the other and the of the desire in Sartre.

En este trabajo nos proponemos presentar algunos movimientos de la lectura crítica que Renaud Barbaras realiza de la filosofía de Sartre. Para eso escogimos, como hilo conductor, la recuperación que este autor hace del dualismo de base de la filosofía sartriana, en continuidad con la crítica de Merleau-Ponty, como modo de abrir otros caminos de reflexión. En estos caminos nos gustaría evidenciar la manera en que Barbaras no solo potencializa la crítica precedente sino el modo en que realiza aproximaciones y problematizaciones originales, que al mismo tiempo en que tornan más evidentes los impases de la filosofía sartriana, no dejan de abrir nuevas posibilidades de investigación. Estos últimos matices son puntuados a través de la crítica propiamente barbarasiana de la cuestión del otro y el deseo en Sartre.

Event-Related Potentials in Major Depressive Disorder / 신경정신의학

Many event-related potentials (ERPs) studies have been performed in major depressive disorder. ERPs include P50, N170, loudness dependence of auditory evoked potentials (LDAEP), P300, and mismatch negativity (MMN). These ERPs have good time-resolution as noninvasive methods, so they can be used easily in clinical practice and research. For example, ERPs can be used to differentiate patients from healthy people, as well as for assessing the subtype and severity, investigating the psychopathology, and predicting the treatment response in mental disorders. This review focuses on P50, N170, LDAEP, P300, and MMN in major depressive disorders.

Neurophysiological and Psychological Predictors of Social Functioning in Patients with Schizophrenia and Bipolar Disorder

OBJECTIVE: The aim of this study is to examine social functioning in patients with schizophrenia and bipolar disorder and explore the psychological and neurophysiological predictors of social functioning. METHODS: Twenty-seven patients with schizophrenia and thirty patients with bipolar disorder, as well as twenty-five healthy controls, completed measures of social functioning (questionnaire of social functioning), neurocognition (Verbal fluency, Korean-Auditory Verbal Learning Test), and social cognition (basic empathy scale and Social Attribution Task-Multiple Choice), and the childhood trauma questionnaire (CTQ). For neurophysiological measurements, mismatch negativity and heart rate variability (HRV) were recorded from all participants. Multiple hierarchical regression was performed to explore the impact of factors on social functioning. RESULTS: The results showed that CTQ-emotional neglect significantly predicted social functioning in schizophrenia group, while HRV-high frequency significantly predicted social functioning in bipolar disorder patients. Furthermore, emotional neglect and HRV-HF still predicted social functioning in all of the subjects after controlling for the diagnostic criteria. CONCLUSION: Our results implicated that even though each group has different predictors of social functioning, early traumatic events and HRV could be important indicators of functional outcome irrespective of what group they are.

Neurophysiological predictors of aphasia recovery in patients with large left-hemispheric infarction: a mismatch negativity study / 中华医学杂志(英文版)

Background@#Although the rehabilitation of aphasia has been extensively studied, the prediction of language outcome still has not received sufficient attention. The aim of this study was to predict the language outcome using mismatch negativity (MMN) in patients with large left-hemispheric infarction.@*Methods@#MMN was elicited by an oddball paradigm in which a standard tone (1000 Hz) and deviant tone (1500 Hz) were presented at 90% and 10% of the number of tones, respectively. The mean amplitudes and laterality indexes (LIs) of MMN were measured over the prefrontal, frontal, central, parietal, temporal, and perisylvian electrodes and both hemispheres during the first 7 days (session 1) and 10 to 20 days (session 2) post-onset. Mixed three-way analysis of variance (ANOVA) was used to investigate differences in these factors between two aphasia groups (the good recovery group and poor recovery group). The predictive value of the most significant LI was also compared with the score of National Institutes of Health Stroke Scale score and low-density volume on computed tomography.@*Results@#A total of 18 patients were enrolled in this study. Mixed three-way ANOVA showed no interaction effect of session × region of interest (ROI) × group (F [3.59, 57.38] = 1.301, P = 0.282) and no interaction effect of ROI × group (F [1.81, 29.01] = 0.71, P= 0.487) and session × group (F [1.00, 16.00]= 0.084, P= 0.776) for MMN amplitude. No interaction effect of session × ROI × group (F [1.79, 28.58] = 0.62, P = 0.530), but an interaction effect of session × group (F [1.00, 16.00] = 5.21, P = 0.036) was found for LIs. In the poor recovery group, the LIs of MMN over all the ROIs, except the parietal area, became more negative at session 2 than those at session 1 (P < 0.05), but this effect was not observed in the good recovery group. Additionally, significant differences were observed in the LIs at session 2 between the two groups (P < 0.05). The LI over the perisylvian area at session 2 had the highest predictive value with an area under the curve of 0.963 (95% confidence interval: 0.884–1.000). An LI score >-0.36 over the perisylvian area suggested good recovery, but a score <-0.36 suggested poor recovery. The LI cut-off value of-0.36 had the highest sensitivity (90.0%) and specificity (87.5%) for predicting a good language outcome at 3 months post-stroke.@*Conclusion@#LIs of MMN amplitudes at approximately 2 weeks post left-hemisphere stroke serve as more sensitive predictors of language outcome, among which the LI over the perisylvian area exhibits the best predictive value.

An Event-related Potential Study of Error-monitoring Deficits in Female College Students Who Participate in Binge Drinking

OBJECTIVE: This study investigated error-monitoring deficits in female college students with binge drinking (BD) using event-related potentials (ERPs) and the modified Flanker task. METHODS: Participants were categorized into BD (n=25) and non-BD (n=25) groups based on the scores of the Korean-version of the Alcohol Use Disorder Identification Test (AUDIT-K) and the Alcohol Use Questionnaire (AUQ). The modified Flanker task, consisting of congruent (target and flanker stimuli are the same) and incongruent (target and flanker stimuli are different) conditions, was used to evaluate error-monitoring abilities. RESULTS: The BD group exhibited significantly shorter response times and more error rates on the Flanker task, as well as reduced error-related negativity (ERN) amplitudes compared with the non-BD group. Additionally, ERN amplitudes measured at FCz and Cz were significantly correlated with scores on the AUDIT-K and AUQ in the whole participants. The BD and non-BD groups did not show any significant differences in error positivity amplitudes. CONCLUSION: The present results indicate that college students with BD have deficits in error-monitoring, and that reduced ERN amplitudes may serve as a biological marker or risk factor of alcohol use disorder.

A dupla potencialidade do irrepresentável e a negatividade necessária: trauma e pulsão de morte / The double potentiality of the irrepresentable and the necessary negativity: trauma and death instinct / La doble potencialidad del irrepresentable y la negatividad necesaria: trauma y pulsión de muerte

Este artigo analisa, a partir de revisão da literatura e articulações teóricas, a dupla potencialidade do não representado, da negatividade e do vazio psíquico, os quais, ao mesmo tempo que apontam para um limite do aparelho psíquico, o lançam para o trabalho, contribuindo para a constituição e diferenciação da subjetividade. Entendemos que o que é tomado pelo psiquismo, em um primeiro momento, como um obstáculo, impassível de digestão mental, em um segundo momento, pode se tornar motor de criação que gerará um novo limite. Essa concepção pode ser deduzida do próprio modo de funcionamento do psiquismo: se, de um lado, pode haver um limite circunstancial de processamento da estimulação endógena e exógena que alcança o aparelho psíquico, de outro lado, através do mecanismo de compulsão à repetição, por exemplo, o esforço do processamento psíquico opera de forma interminável. Os diferentes modelos a partir dos quais o conceito de trauma pode ser pensado servirão de fio condutor para analisar os efeitos e os destinos psíquicos do irrepresentado, bem como para articular essas ideias com os conceitos de repetição e pulsão de morte.

This article analyses, from a literature review and theoretical articulations, the double potentiality of the unrepresented, of negativity and of emptiness over the psyche, that at the same time points out a limit of the psychic apparatus, lances it for work, contributing for subjective constitution and differentiation. The direction chosen here favors the idea that what is taken in the first place by the psyche as an obstacle, impassible of mental digestion, at a second moment can turn out to be a motor of surpassingness that will engender a new limit. This conception can be deducted from the own way that psyche functions, because if in one hand there can be a circumstantial limit of processing endogenous and exogenous stimulation that reaches the psychic apparatus, in the other hand, through compulsion repetition mechanism, for example, the effort of psychic processing operates in an interminable way. The different models that the concept of trauma can be thought through will serve as a conducting wire to analyze the effects and psychic destinies of the unrepresented, as well as to articulate these ideas with the concepts of repetition and death instinct.

Este artículo analiza, a partir de revisión de la literatura y articulaciones teóricas, la doble potencialidad del irrepresentado, de la negatividad y del vacío psíquico, los cuales, al mismo tiempo que apuntan hacia un límite del aparato psíquico, lo lanzan para el trabajo, contribuyendo a la constitución y diferenciación de la subjetividad. Entendemos que lo que es tomado por el psiquismo, en un primer momento, como un obstáculo, impasible de digestión mental, en un segundo momento, puede convertirse en motor de creación que generará un nuevo límite. Esta concepción puede ser deducida del propio modo de funcionamiento del psiquismo: si, por un lado, puede haber un límite circunstancial de procesamiento de la estimulación endógena y exógena que alcanza el aparato psíquico, por otro lado, a través del mecanismo de compulsión a la repetición, por ejemplo, el esfuerzo del procesamiento psíquico opera de forma interminable. Los diferentes modelos a partir de los cuales el concepto de trauma puede ser pensado servirán de hilo conductor para analizar los efectos y los destinos psíquicos del irrepresentado, así como para articular esas ideas con los conceptos de repetición y pulsión de muerte.

Effect of the Standardization of Diagnostic Tests on the Prevalence of Diabetes Mellitus and Impaired Fasting Glucose

BACKGROUND: Without standardization of medical laboratory's testing practices, there is an increase in false diagnoses when relying on test results. However, the effect of test standardization is difficult to assess numerically. This study's purpose is to quantify the effect of the standardization level of a laboratory on the prevalence of diabetes mellitus (DM) and impaired fasting glucose (IFG). METHODS: Laboratories were classified into three levels: ‘highly-standardized laboratory,’‘basically-standardized laboratory,’ and ‘non-standardized laboratory.’ Based on the results of Korean External Quality Assessment Scheme (KEQAS), the cutoff values for diagnosis of DM and IFG were recalculated, given false positive and false negative rates. RESULTS: The prevalence of DM and IFG in the population as a whole was estimated using the 2013 Korea National Health and Nutrition Examination Survey (KNHANES) database. When the prevalence of DM from KNHANES was 11.88% (95% confidence interval [CI], 10.59%–13.17%), the proportion with a systematic false error ranged from 10.91% (95% CI, 9.65%–12.17%) to 13.09% (95% CI, 11.74%–14.45%). The prevalence of IFG varied from 13.59% (95% CI, 12.25%–14.91%) to 40.49% (95% CI, 38.54%–42.43%), in contrast to 24.58% (95% CI, 22.85%–26.31%) of the reference value. The prevalence of DM and IFG tended to be over- and under-estimated more as the laboratory standardization level became lower, respectively. CONCLUSION: Our study proved that standardization of clinical laboratory tests is an important factor affecting the prevalence estimation of national disease statistics based on the simulation using KNHANES data.

An event-related potential objective evaluation study of mental fatigue based on 2-back task / 生物医学工程学杂志

The electroencephalographic characteristics of mental fatigue, which was induced by long-term working memory task of 2-back, were studied by event-related potential (ERP) technology in order to obtain objective evaluation indicators for mental fatigue. Thirty-two healthy male subjects, 22-28 years old, were divided into two groups evenly, one is un-fatigue group and the other is fatigue group. The fatigue group performed a 2-back task for 100 min continuously, while the un-fatigue group just performed a 2-back task at the first and last 10 min respectively, and rested during the middle 80 min. The subjective levels of fatigue, task performance and electroencephalogram were recorded. The impaired thought and attention states, enhanced sleepy and fatigue feeling were found in the fatigue group, meanwhile their reaction time to 2-back task extended, and the accuracy decreased significantly. These results verified the validity of mental fatigue model induced by 2-back task, and then the ERP characteristic parameters were compared and analyzed between fatigue group and un-fatigue group. The results showed that the fatigue group's amplitudes of P300 ( = 2.539, 0.05). These results demonstrate that P300 and ERN can be considered as potential evaluation indictors for mental fatigue induced by long-term working memory task, which will provide basis for the future exploring of countermeasure for mental fatigue.

A research for single trial detection of error related negativity / 生物医学工程学杂志

Error related negativity (ERN) is generated in frontal and central cortical regions when individuals perceive errors. Because ERN has low signal-to-noise ratio and large individual difference, it is difficult for single trial ERN recognition. In current study, the optimized electroencephalograph (EEG) channels were selected based on the brain topography of ERN activity and ERN offline recognition rate, and the optimized EEG time segments were selected based on the ERN offline recognition rate, then the low frequency time domain and high frequency time-frequency domain features were analyzed based on wavelet transform, after which the ERN single detection algorithm was proposed based on the above procedures. Finally, we achieved average recognition rate of 72.0% ± 9.6% in 10 subjects by using the sample points feature in 0~3.9 Hz and the power and variance features in 3.9~15.6 Hz from the EEG segments of 200~600 ms on the selected 6 channels. Our work has the potential to help the error command real-time correction technique in the application of online brain-computer interface system.

Spatial Properties of Mismatch Negativity in Patients with Disorders of Consciousness / 神经科学通报·英文版

In recent decades, event-related potentials have been used for the clinical electrophysiological assessment of patients with disorders of consciousness (DOCs). In this paper, an oddball paradigm with two types of frequency-deviant stimulus (standard stimuli were pure tones of 1000 Hz; small deviant stimuli were pure tones of 1050 Hz; large deviant stimuli were pure tones of 1200 Hz) was applied to elicit mismatch negativity (MMN) in 30 patients with DOCs diagnosed using the JFK Coma Recovery Scale-Revised (CRS-R). The results showed that the peak amplitudes of MMN elicited by both large and small deviant stimuli were significantly different from baseline. In terms of the spatial properties of MMN, a significant interaction effect between conditions (small and large deviant stimuli) and electrode nodes was centered at the frontocentral area. Furthermore, correlation coefficients were calculated between MMN amplitudes and CRS-R scores for each electrode among all participants to generate topographic maps. Meanwhile, a significant negative correlation between the MMN amplitudes elicited by large deviant stimuli and the CRS-R scores was also found at the frontocentral area. In consequence, our results combine the above spatial properties of MMN in patients with DOCs, and provide a more precise location (frontocentral area) at which to evaluate the correlation between clinical electrophysiological assessment and the level of consciousness.