Patient-Reported Postoperative Neuropsychological Deterioration After Heart Valve Replacement and Coronary Artery Bypass Grafting.

Background: Postoperative cognitive decline (POCD) after cardiosurgical interventions are well described through objective psychometric tests. However, a patient's subjective perception is essential to clinical assessment and quality of life. This study systematically evaluated patient-reported POCD between subjects undergoing coronary artery bypass grafting and heart valve replacement. Methods: This study was a multicentre, prospective questionnaire survey conducted at the cardiac surgery departments at the Kerckhoff Clinic in Bad Nauheim and the University Hospital in Giessen, Germany. We included patients undergoing elective coronary artery bypass grafting (CABG), aortic valve replacement (AVR), mitral valve replacement or reconstruction (MVR), and combined surgery (CABG + valve replacement [VR]) with extracorporeal circulation. The Hospital Anxiety and Depression Scale, the Cognitive Failures Questionnaire (CFQ) for Self-assessment (CFQ-S), and the external assessment (CFQ-foreign [F]) were completed preoperatively, as well as at 3 and 12 months postoperatively. Results: A total of 491 patients were available for analyses (CABG = 182, AVR = 134, MVR = 93, CABG + VR = 82). POCD and postoperative depression increase (PODI) were observed for each surgical procedure. (At the 3-month follow-up: CFQ-S [CABG = 7.1%, AVR = 3.7%, MVR = 9.7%, CABG + VR = 9.8%]; CFQ-F [CABG = 9.9%, AVR = 9.7%, MVR = 9.7%, CABG + VR = 15.9%]; PODI [CABG = 7.7%, AVR = 9.7%, MVR = 6.5%, CABG + VR = 8.5%]. At the 12-month follow-up: CFQ-S [CABG = 6.6%, AVR = 7.5%, MVR = 15.1%, CABG + VR = 7.3%]; CFQ-F [CABG = 7.1%, AVR = 14.9%, MVR = 10.8%, CABG + VR = 9.8%]; PODI [CABG = 10.4%, AVR = 11.2%, MVR = 6.5%, CABG + VR = 4.9%]). No significant between-group effects were observed for the CFQ-S, CFQ-F, or the Hospital Anxiety and Depression Scale. Conclusions: For clinicians, paying attention to patients' self-reported experiences of reduced cognitive function and symptoms of depression following cardiac surgery is important. Such reporting is an indication that interventions such as cognitive training or psychotherapy should be considered.

Contexte: Le déclin cognitif postopératoire (DCPO) à la suite d'interventions de chirurgie cardiaque est bien décrit par des évaluations psychométriques objectives. Cependant, la perception subjective du patient est essentielle à l'évaluation clinique et à la qualité de vie. Cette étude visait à évaluer de façon systématique le DCPO déclaré par le patient chez des sujets ayant subi un pontage aortocoronarien ou une chirurgie valvulaire. Méthodologie: Cette étude prospective multicentrique par questionnaire a été menée aux services de chirurgie cardiaque de la clinique Kerckhoff de Bad Nauheim et de l'hôpital universitaire de Giessen, en Allemagne. Elle a porté sur des patients ayant subi un pontage aortocoronarien (PAC), un remplacement valvulaire aortique (RVA), un remplacement ou une reconstruction de la valvule mitrale (RVM) ou une chirurgie combinée (PAC et remplacement valvulaire [RV]) avec circulation extracorporelle, en situation non urgente. L'échelle d'évaluation de l'anxiété et de la dépression à l'hôpital (HADS), le questionnaire d'auto-évaluation des déficits cognitifs (CFQ-S) et le questionnaire d'évaluation externe des déficits cognitifs (CFQ-F) ont été remplis avant l'intervention chirurgicale, ainsi que 3 et 12 mois après la chirurgie. Résultats: Au total, les résultats de 491 patients étaient disponibles aux fins d'analyses (PAC = 182, RVA = 134, RVM = 93, PAC et RV = 82). Des cas de DCPO et une augmentation postopératoire des symptômes de dépression (APOD) ont été observés après chacune des interventions chirurgicales. (Lors du suivi après 3 mois : DCPO selon le CFQ-S [PAC = 7,1 %, RVA = 3,7 %, RVM = 9,7 %, PAC + RV = 9,8 %]; DCPO selon le CFQ-F [PAC = 9,9 %, RVA = 9,7 %, RVM = 9,7 %, PAC + RV = 15,9 %]; APOD [PAC = 7,7 %, RVA = 9,7 %, RVM = 6,5 %, PAC + RV = 8,5 %]. Lors du suivi après 12 mois : DCPO selon le CFQ-S [PAC = 6,6 %, RVA = 7,5 %, RVM = 15,1 %, PAC + RV = 7,3 %]; DCPO selon le CFQ-F [PAC= 7,1 %, RVA = 14,9 %, RVM = 10,8 %, PAC+ RV = 9,8 %]; APOD [PAC = 10,4 %, RVA = 11,2 %, RVM = 6,5 %, PAC + RV = 4,9 %]). Aucun effet intergroupe significatif n'a été observé relativement aux questionnaires CFQ-S et CFQ-F ou à l'échelle HADS. Conclusions: Il est important que les cliniciens portent attention aux déclarations des patients en ce qui concerne la diminution des fonctions cognitives et les symptômes de dépression à la suite d'une chirurgie cardiaque. De telles déclarations sont une indication que des interventions comme l'entraînement cognitif ou la psychothérapie doivent être envisagées.

Twelve-month follow-up effects of cognitive training after heart valve surgery on cognitive functions and health-related quality of life: a randomised clinical trial.

OBJECTIVES: Postoperative cognitive decline (POCD) or decreased health-related quality of life (HQL) have been reported after cardiac surgery. A previous investigation showed beneficial effects of postoperative cognitive training on POCD and HQL 3 months after heart surgery. Here, we present the 12-month follow-up results. METHODS: This bicentric, 1:1 randomised and treatment-as-usual controlled trial included elderly patients scheduled for elective heart valve surgery. The training consisted of paper-and-pencil-based exercises practising multiple cognitive functions for 36 min/day 6 days/week over a period of 3 weeks. Neuropsychological tests and questionnaires assessing HQL (36-Item Short Form Health Survey (SF-36)) and cognitive failures in daily living (Cognitive Failures Questionnaire) were performed presurgery and 12 months after training. RESULTS: Twelve months post training, the training group (n=30) showed improvements in HQL compared with the control group (n=28), especially in role limitations due to physical health (U=-2.447, p=0.015, η2=0.109), role limitations due to emotional problems (U=-2.245, p=0.025, η2=0.092), pain (U=-1.979, p=0.049, η2=0.068), average of all SF-36 factors (U=-3.237, p<0.001, η2=0.181), health change from the past year to the present time (U=-2.091, p=0.037, η2=0.075), physical component summary (U=-2.803, p=0.005, η2=0.138), and mental component summary (U=-2.350, p=0.018, η2=0.095). Furthermore, the training group (n=19) showed an improvement compared with the control group (n=27) in visual recognition memory (U=-2.137, p=0.034, η2=0.099). POCD frequency was 22% (n=6) in the control group and 11% (n=2) in the training group (χ²(1) =1.06, p=0.440; OR=2.43, 95% CI 0.43 to 13.61). CONCLUSION: In conclusion, postoperative cognitive training shows enhancing effects on HQL in cardiac surgery patients after 12 months.

The impact of postoperative cognitive training on health-related quality of life and cognitive failures in daily living after heart valve surgery: A randomized clinical trial.

BACKGROUND: Heart surgery is a risk factor for objectively and subjectively assessable postoperative cognitive decline (POCD), which is relevant for everyday life. The aim of this study was to investigate whether early postoperative cognitive training has an impact on health-related quality of life and cognitive failures in daily living after cardiac surgery. METHODS: The study was a two-arm, randomized, controlled, outcome-blinded trial involving older patients undergoing elective heart valve surgery with extracorporeal circulation (ECC). Recruitment took place at the Departments of Cardiac Surgery of the Kerckhoff Clinic in Bad Nauheim (Germany) and the University Hospital in Giessen (Germany). The patients were randomized (1:1 ratio) to either a paper-and-pencil-based cognitive training group or a control group. We applied the Short Form Health Survey (SF-36) and the Cognitive Failures Questionnaire (CFQ) prior to surgery and 3 months after the cognitive training. Data were analyzed in a per-protocol fashion. RESULTS: Three months after discharge from rehabilitation, the training group (n = 31) showed improvement in health-related quality of life compared to the control group (n = 29), especially in role limitations due to emotional problems (U = -2.649, p = .008, η2  = 0.121), energy and fatigue (F[2.55] = 5.72, p = .020, η2  = 0.062), social functioning (U = -2.137, p = .033, η2  = 0.076), the average of all SF-36 factors (U = -2.374, p = .018, η2  = 0.094), health change from the past year to the present time (U = -2.378, p = .017, η2  = 0.094), and the mental component summary (U = -2.470, p = .013, η2  = 0.102). CONCLUSION: As our cognitive training has shown beneficial effects, this intervention could be a promising method to enhance health-related quality of life after cardiac surgery.

Increasing preoperative cognitive reserve to prevent postoperative delirium and postoperative cognitive decline in cardiac surgical patients (INCORE): Study protocol for a randomized clinical trial on cognitive training.

Introduction: Postoperative delirium (POD) and postoperative cognitive decline (POCD) can be observed after cardiosurgical interventions. Taken together, these postoperative neurocognitive disorders (PNCDs) contribute to increased morbidity and mortality. Preoperative risk factors of PNCD, such as decreased neuropsychometric performance or decreased cognitive daily activities, can be interpreted as reduced cognitive reserve. This study aims to build up cognitive reserves to protect against the development of PNCD through preoperative, home-based, cognitive training. Methods: The planned research project is a monocentric, two-arm randomized controlled intervention study involving 100 patients undergoing elective cardiac surgery with extracorporeal circulation. Patients will be assigned to a training group or control group. The intervention involves a standardized, paper-and-pencil-based cognitive training that will be performed by the patients at home for ~40 min per day over a preoperative period of 2-3 weeks. The control group will receive neither cognitive training nor a placebo intervention. A detailed assessment of psychological functions will be performed ~2-3 weeks before the start of training, at the end of the training, during hospitalization, at discharge from the acute clinic, and 3 months after surgery. The primary objective of this study is to investigate the interventional effect of preoperative cognitive training on the incidence of POD during the stay in the acute clinic, the incidence of POCD at the time of discharge from the acute clinic, and 3 months after surgery. Secondary objectives are to determine the training effect on objective cognitive functions before the surgery and subjective cognitive functions, as well as health-related quality of life 3 months after surgery. Discussion: Should it become evident that the use of our cognitive training can both reduce the incidence of POCD and POD and improve health-related quality of life, this intervention may be integrated into a standardized prehabilitation program.

Visual Hallucinations following Coronary Artery Bypass Grafting: A Prospective Study.

Background and Objectives: After major heart surgery, some patients report visual hallucinations that cannot be attributed to psychosis or delirium. This study aimed to investigate the hallucination incidence in patients after coronary artery bypass grafting with (on-pump) and without (off-pump) extracorporeal circulation. Materials and Methods: A total of 184 consecutive patients listed for elective on- or off-pump coronary artery bypass grafting were prospectively enrolled into the study. Preoperative baseline investigations 24-48 h before surgery (t0) and postoperative follow-up 24-48 h (t1) and 5-6 days (t2) after surgery included cognitive testing and a clinical visual acuity test (Landolt rings). Patients reporting visual hallucinations were interviewed using a structured survey to record the type, timing, duration, and frequency of their hallucinations. All the patients received a neurological examination and cranial magnetic resonance imaging if indicated. Results: Of the patients in the sample, 155 patients underwent on-pump bypass surgery, and 29 patients received off-pump surgery. Of these, 25 patients in the on-pump group, but none in the off-pump group, reported transient visual hallucinations (p = 0.020), which could not be attributed to stroke, delirium, psychosis, migraine, or severely impaired vision. Significant correlations were observed for the occurrence of visual hallucinations and the amount of nicotine consumption and aortic clamp/extracorporeal circulation time. Conclusions: Transient visual hallucinations occur in a noticeable proportion of patients after on-pump heart surgery. Knowledge of the phenomenon's benignity is important for patients to prevent anxiety and uncertainty and for treating physicians to avoid unnecessary medication and drug-induced delirium.

Effects of postoperative cognitive training on neurocognitive decline after heart surgery: a randomized clinical trial.

OBJECTIVES: Following cardiac surgery, postoperative cognitive decline (POCD) is a common complication that can impair the quality of life and increase mortality. The aim of this study was to investigate whether early postoperative cognitive training can decrease POCD after cardiac surgery. METHODS: The study was a multi-centred, two-arm, randomized (1:1 ratio), controlled trial involving older patients undergoing elective heart valve surgery with extracorporeal circulation. Recruitment took place at the Department of Cardiac Surgery of the Kerckhoff-Clinic in Bad Nauheim (Germany) and the University-Hospital in Giessen (Germany). The patients were randomized to either a paper-and-pencil-based cognitive training group or a standard rehabilitation care control group. The cognitive training started 1 week after surgery and lasted about 3 weeks until discharge from rehabilitation. To detect POCD, neuropsychological functions were assessed prior to surgery, upon discharge from rehabilitation (primary outcome), and 3 months after discharge (secondary outcome). Data were primarily analysed in a per-protocol fashion. RESULTS: The frequency of POCD at discharge from rehabilitation (training group, n = 37; control group, n = 44) was 50% in the control group and 19% in the training group (χ2[1] = 8.45, P = 0.004; odds ratio = 4.29, 95% confidence interval [1.56-11.80]). Three months after the cognitive training (training group, n = 33; control group, n = 34), POCD frequency was 29% in the control group and 6% in the training group (χ2[1] = 6.21, P = 0.013; odds ratio = 6.46, 95% confidence interval [1.29-32.28]). CONCLUSIONS: Since our cognitive training showed beneficial effects, it could be a promising method to prevent POCD.

Neuroprotective effects of dynamic bubble trap use in patients undergoing pulmonary endarterectomy: a two-arm randomized controlled trial.

BACKGROUND: During cardiosurgical procedures that use extracorporeal circulation (ECC), a variety of neurological complications can occur, and postoperative cognitive deficits remain an unsolved problem. Among the sources of these complications are intraoperatively detectable cerebral microemboli, which mainly consist of air. This study's purpose was to assess neuroprotective effects of reducing these gaseous microemboli using a dynamic bubble trap (DBT) in patients undergoing pulmonary endarterectomy (PEA) for the treatment of chronic thromboembolic pulmonary hypertension (CTEPH). METHODS: Patients undergoing PEA were randomly assigned to receive either a DBT (n=47) or no additional device (controls, n=46) during ECC. Neuropsychological testing was performed before and 3 months after PEA. The primary endpoint was cognitive improvement in the DBT group (n=29) compared with the control group (n=42). As secondary endpoint, ischemic brain micro-lesions were analyzed on postoperative days 6 through 10 using diffusion-weighted magnetic resonance imaging (MRI). RESULTS: Analysis of interaction effects revealed improved performance in visual long-term memory (P=0.008, η2=0.099), verbal long-term memory (P=0.030, η2=0.067), verbal short-term memory (P=0.014, η2=0.083), and attention and processing speed (P=0.043, η2=0.056) from pre- to post-testing in the DBT group compared to control group. In MRI, postoperative ischemic micro-lesions could only be detected in one patient; another patient suffered a severe bihemispheric embolic stroke. CONCLUSIONS: DBT positively influences memory function after PEA. This effect is most likely caused by the reduction of gaseous microemboli. TRIAL REGISTRATION: This study is registered in the German Clinical Trials Register, ID: DRKS00021499.

Case Report: Neuropsychological Findings in IgLON5 Antibody Disorder.

IgLON5 antibody encephalopathy is a rare but increasingly recognized disorder with a variety of clinical signs. Typical symptoms are sleep disorder, gait disturbances, signs of bulbar dysfunction and a variety of neurological symptoms like oculomotor abnormalities and movement disorders. In addition, cognitive decline can be a prominent symptom. So far, there are only a few studies that have dealt with the course and possible treatment options of IgLON5 antibody encephalopathy. In this study the clinical case of a female patient with IgLON5 antibody disease and the response to treatment is described. Here we report on the case of a 67-year-old female patient who showed cognitive deterioration, gait difficulties, and chronic obstructive sleep disorder. The diagnostic course showed a positive anti-IgLON5 serum and anti-IgLON5 IgG antibodies in cerebrospinal fluid. The patient was subsequently treated with high dosage i.v. methylprednisolone, i.v. immunoglobulins and plasmapheresis. Neuropsychological tests showed cognitive deficits in different domains, including verbal and visual memory. Both, neuropsychological deficits and antibody titer, showed an improvement after plasmapheresis. The presented case shows that IgLON5 disease can present with rapidly progressing cognitive deterioration as the prominent symptom, adding to the variety of clinical signs in this disorder. Testing for IgLON5-antibodies should be considered in patients with progressing cognitive decline, especially if accompanied by sleep disorders or neurological symptoms like oculomotor abnormalities, dysautonomia or bulbar signs.

BAFF serum and CSF levels in patients with multiple sclerosis and infectious nervous system diseases.

PURPOSE: Multiple sclerosis (MS) is the most common immune-mediated CNS disease, characterised by demyelination and progressive neurological disability. The B-cell activating factor BAFF has been described as one important factor in the pathophysiology of different autoimmune diseases. METHODS: We measured BAFF levels in the serum and cerebrospinal fluid (CSF) in 50 consecutive patients with MS and 35 patients with infectious CNS disease (ID). 52 patients with other, non-inflammatory disorders (OND), served as controls. RESULTS: BAFF-serum levels in ID patients were higher than in patients diagnosed with MS (ID 0.55 ± 0.24 ng/ml, MS 0.43 ± 0.14 ng/ml, OND 0.45 ± 0.24 ng/ml; p = 0.09). Interestingly, MS patients had lower BAFF CSF levels compared to the controls and ID patients, and the CSF levels in the latter were elevated compared to those of the controls (MS 0.17 ± 0.11 ng/ml, OND 0.25 ± 0.14 ng/ml, ID 0.97 ± 0.78 ng/ml; p < 0.001). CONCLUSIONS: The ID patients' having higher absolute BAFF levels in the CSF than in the serum indicates that the increased BAFF CSF levels were caused by intrathecal synthesis rather than passive transfer via a disturbed blood-brain-barrier. The significantly decreased BAFF CSF levels in MS patients were a surprising result of our study. Although it has been reported that astrocytes in active MS lesions can express BAFF, the soluble form was not increased in the CSF of MS patients. It remains unclear whether the inflammatory features of active MS plaques are truly represented by the CSF compartment.

Epileptic seizure discharges in patients after open chamber cardiac surgery-a prospective prevalence pilot study using continuous electroencephalography.

PURPOSE: Patients undergoing cardiac surgery often develop delirium which increases the risk of postoperative morbidity and leads to a reduced quality of life. Retrospective studies show a higher incidence of delirium in patients with seizures. However, these studies do not systematically detect subclinical seizures, so the incidence of seizures after cardiac surgery remains speculative. The objective of this study is to determine the prevalence of electrographic seizures after elective open-chamber cardiac surgery. METHODS: This prospective, blinded, monocentric, observational study investigated patients scheduled for elective open-chamber valve reconstruction or replacement. Anaesthesia, surgery and postoperative treatment were standardized and not influenced by the presented observation. After surgery, all patients arrived at the ICU, and EEG monitoring started within the first hour. EEG recording was continuously performed for up to 24 h, and the results were independently analysed by two blinded EEG board-certified neurologists. RESULTS: 100 patients were included. Abnormal EEG patterns were present in 33% of patients, and 9% of all patients showed electrographic seizures. The main EEG activity at the beginning of each recording was suppressed or showed a burst-suppression pattern, and at the end of recording, all patients had an alpha/theta rhythm. An association between electrographic seizures and delirium was found (pχ2 < 0.01). CONCLUSION: This study reveals a surprisingly high incidence of abnormal EEG patterns and electrographic seizures in patients undergoing open-chamber cardiac surgery. As electrographic seizures are associated with the incidence of delirium, this finding is a relevant phenomenon in the post-cardiac surgery ICU population.

Decreasing postoperative cognitive deficits after heart surgery: protocol for a randomized controlled trial on cognitive training.

BACKGROUND: The occurrence of postoperative cognitive deficits, especially after heart surgery, has been demonstrated in several studies. These deficits can clearly be noticed by the patients and by their close relatives in daily life. Furthermore, postoperative cognitive deficits can decrease quality of life in social functioning and earning capacity. The aim of this study is to investigate whether early postoperative cognitive training can reduce subjective and objective postoperative cognitive deficits. METHODS: The proposed study is a multicenter, two-arm, randomized controlled trial involving 144 elderly patients undergoing elective heart-valve surgery with extracorporeal circulation. Patients will be assigned to either a training group or a control group. The intervention involves paper-and-pencil-based cognitive training, which is conducted for 36 min over a period of 18 days. The training starts about 1 week after surgery and is carried out during the hospitalized rehabilitation phase. The control group will not receive cognitive training or a placebo intervention. A detailed assessment of psychological functions and health-related quality of life prior to surgery at discharge from rehabilitation and 3 and 12 months after discharge will be performed. The primary outcome of this trial is the training effect on objective cognitive functions at discharge from rehabilitation. Secondary outcomes are the training effect on objective and subjective cognitive functions (3 and 12 months after discharge), depression, health-related quality of life, and the impact of perioperative cerebral ischemia on the training effect. Perioperative cerebral ischemia will be measured with postoperative magnetic resonance imaging including diffusion-weighted sequences. DISCUSSION: Should it be shown that our cognitive training can improve postoperative cognitive deficits and quality of life, one possibility could be to integrate this intervention into early rehabilitation. Furthermore, we hope that the investigation of perioperative ischemia by diffusion-weighted magnetic resonance imaging will improve our understanding of neurobiological factors influencing the course of postoperative cognitive plasticity. TRIAL REGISTRATION: German Clinical Trials Register (DRKS), DRKS00015512. Retrospectively registered on 21 September 2018.

Inter- and intra-rater reliability of computer-assisted planimetry in experimental stroke research.

BACKGROUND: Computer-assisted planimetry is widely used in experimental stroke research to assess the size of the ischemic lesion or hemispheric volume. NEW METHOD: Only insufficient data exist on the training required to achieve sufficient reliability in planimetry. Therefore, planimetry was performed over 15 months by two blinded raters who were initially inexperienced in the method. For inter-rater reliability, the hemispheric and lesional volume of 227 male Wistar Unilever rats subjected to middle cerebral artery occlusion were determined in diffusion- and T2-weighted sequences. For the intra-rater agreement, one investigator assessed the hemispheric and lesional volume in 87 T2-weighted sequences twice within a six-week interval. The correlation was calculated using Krippendorff's alpha and Bland-Altman plots illustrated the agreement. RESULTS: Inter-rater agreement increased during the first seven weeks and remained at high values (Krippendorff's alpha > 0.88). For intra-rater agreement, Krippendorff's alpha was 0.84 for hemispheric and 0.85 for lesional volume. The Bland-Altman plot indicated solid agreement between raters in the absence of systematic errors. COMPARISON WITH EXISTING METHODS: Simplified geometrical models or automated methods for planimetry can be used to determine lesional volume, but both approaches are inappropriate to assess hemispheric volume. CONCLUSION: Computer-assisted planimetry can be an appropriate method to determine hemispheric or ischemic lesion volume in rodents but requires a sufficiently long learning period of approximately two months. Even an experienced investigator can generate data with serious variation. Inter- and intra-rater-dependent bias should be considered during the design and performance of respective studies.

Continuous electroencephalography in a mixed non-neurological intensive care population, an observational study.

PURPOSE: Continuous electroencephalography (cEEG) improves monitoring of the brain in unconscious patients, but implementation at ICU is difficult. The present investigation shows a way to introduce cEEG at an anesthesiological ICU and discusses the first experiences. MATERIALS AND METHODS: The study analyzed the feasibility of cEEG, assessed the interpretable cEEG time, importance of automatic seizure detection, the incidence of seizures, the predominant background EEG activity, incidence of delirium and mortality. RESULTS: Fifty-three cEEGs of 50 patients with a median interpretable length of 24 hours [IQR 20 to 42 hours] were recorded. One patient had status epilepticus, while 5 patients had non-convulsive seizures. Automated seizure detection recognized the status epilepticus and 3 of 10 non-convulsive seizures, however, detected 42 false positive seizures. Predominant background EEG activity was alpha (9%), theta (17%), delta (26%), burst-suppression (17%), and suppressed background activity (30%). EEG activity correlated neither with dosage of analgo-sedative drugs nor with incidence of delirium or mortality. CONCLUSION: Continuous electroencephalography recording is feasible and manageable. Automatic seizure detection was often false negative/positive; therefore, the interpretation of the cEEG should be supported by EEG-trained neurologists. Background EEG activity was not associated with outcome parameters, which suggests that background activity is a poor outcome predictor.

The Idea Is Good, but : Failure to Replicate Associations of Oxytocinergic Polymorphisms with Face-Inversion in the N170.

BACKGROUND: In event-related potentials, the N170 manifests itself especially in reaction to faces. In the healthy population, face-inversion leads to stronger negative amplitudes and prolonged latencies of the N170, effects not being present in patients with autism-spectrum-disorder (ASD). ASD has frequently been associated with differences in oxytocinergic neurotransmission. This ERP-study aimed to investigate the face-inversion effect in association with oxytocinergic candidate genes. It was expected that risk-allele-carriers of the oxytocin-receptor-gene-polymorphism (rs53576) and of CD38 (rs379863) responded similar to upright and inverted faces as persons with ASD. Additionally, reactions to different facial emotional expressions were studied. As there have been difficulties with replications of those molecular genetic association studies, we aimed to replicate our findings in a second study. METHOD: Seventy-two male subjects in the first-, and seventy-eight young male subjects in the replication-study conducted a face-inversion-paradigm, while recording EEG. DNA was extracted from buccal cells. RESULTS: Results revealed stronger N170-amplitudes and longer latencies in reaction to inverted faces in comparison to upright ones. Furthermore, effects of emotion on N170 were evident. Those effects were present in the first and in the second study. Whereas we found molecular-genetic associations of oxytocinergic polymorphisms with the N170 in the first study, we failed to do so in the replication sample. CONCLUSION: Results indicate that a deeper theoretical understanding of this research-field is needed, in order to generate possible explanations for these findings. Results, furthermore, support the hypotheses that success of reproducibility is correlated with strength of lower original p-values and larger effect sizes in the original study.