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Monitoring for errors and behavioral adjustments after errors are essential for daily life. A question that has not been addressed systematically yet, is whether consciously perceived errors lead to different behavioral adjustments compared to unperceived errors. Our goal was to develop a task that would enable us to study different commonly observed neural correlates of error processing and post-error adjustments in their relation to error awareness and accuracy confidence in a single experiment. We assessed performance in a new number judgement error awareness task in 70 participants. We used multiple, robust, single-trial EEG regressions to investigate the link between neural correlates of error processing (e.g., error-related negativity (ERN) and error positivity (Pe)) and error awareness. We found that only aware errors had a slowing effect on reaction times in consecutive trials, but this slowing was not accompanied by post-error increases in accuracy. On a neural level, error awareness and confidence had a modulating effect on both the ERN and Pe, whereby the Pe was most predictive of participants’ error awareness. Additionally, we found partial support for a mediating role of error awareness on the coupling between the ERN and behavioral adjustments in the following trial. Our results corroborate previous findings that show both an ERN/Pe and a post-error behavioral adaptation modulation by error awareness. This suggests that conscious error perception can support meta-control processes balancing the recruitment of proactive and reactive control. Furthermore, this study strengthens the role of the Pe as a robust neural index of error awareness.

•We examined how task-irrelevant information biases our decisions.•Task-irrelevant information biases learning and behaviour despite explicit knowledge of its irrelevance.•These biases are represented in a dynamic and spatiotemporally dissociable sequence of feedback-related EEG activity.•A common centroparietal positivity reflects a signal that is interpreted by downstream learning processes that adjust future behaviour. Optimal decision making in complex environments requires dynamic learning from unexpected events. To speed up learning, we should heavily weight information that indicates state-action-outcome contingency changes and ignore uninformative fluctuations in the environment. Often, however, unrelated information is hard to ignore and can potentially bias our learning. Here we used computational modelling and EEG to investigate learning behaviour in a modified probabilistic choice task that introduced two task-irrelevant factors that were uninformative for optimal task performance, but nevertheless could potentially bias learning: pay-out magnitudes were varied randomly and, occasionally, feedback presentation was enhanced by visual surprise. We found that participants’ overall good learning performance was biased by distinct effects of these non-normative factors. On the neural level, these parameters are represented in a dynamic and spatiotemporally dissociable sequence of EEG activity. Later in feedback processing the different streams converged on a central to centroparietal positivity reflecting a signal that is interpreted by downstream learning processes that adjust future behaviour.

•Multiple regression reveals independent contributions to feedback-locked EEG signal.•Factors influencing FRN and P3a/b revealed in a large sample.•Prediction error, valence & surprise are multiplexed across latency and topography.•Particularly stronger coding of expectancy in positive compared to negative outcome.•P3 driven by expectancy, outcomes, their interaction predicts behavioral adjustments. The feedback-related negativity (FRN) is a well-established electrophysiological correlate of feedback-processing. However, there is still an ongoing debate whether the FRN is driven by negative or positive reward prediction errors (RPE), valence of feedback, or mere surprise. Our study disentangles independent contributions of valence, surprise, and RPE on the feedback-related neuronal signal including the FRN and P3 components using the statistical power of a sample of N = 992 healthy individuals. The participants performed a modified time-estimation task, while EEG from 64 scalp electrodes was recorded. Our results show that valence coding is present during the FRN with larger amplitudes for negative feedback. The FRN is further modulated by surprise in a valence-dependent way being more positive-going for surprising positive outcomes. The P3 was strongly driven by both global and local surprise, with larger amplitudes for unexpected feedback and local deviants. Behavioral adaptations after feedback and FRN just show small associations. Results support the theory of the FRN as a representation of a signed RPE. Additionally, our data indicates that surprising positive feedback enhances the EEG response in the time window of the P3. These results corroborate previous findings linking the P3 to the evaluation of PEs in decision making and learning tasks.

Performance monitoring (PM) is a vital component of adaptive behavior and known to be influenced by motivation. We examined effects of potential gain (PG) and loss avoidance (LA) on neural correlates of PM at different processing stages, using a task with trial-based changes in these motivational contexts. Findings suggest more attention is allocated to the PG context, with higher amplitudes for respective correlates of stimulus and feedback processing. The PG context favored rapid responses, while the LA context emphasized accurate responses. Lower response thresholds in the PG context after correct responses derived from a drift–diffusion model also indicate a more approach-oriented response style in the PG context. This cognitive shift is mirrored in neural correlates: negative feedback in the PG context elicited a higher feedback-related negativity (FRN) and higher theta power, whereas positive feedback in the LA context elicited higher P3a and P3b amplitudes, as well as higher theta power. There was no effect of motivational context on response-locked brain activity. Given the similar frequency of negative feedback in both contexts, the elevated FRN and theta power in PG trials cannot be attributed to variations in reward prediction error. The observed variations in the FRN indicate that the effect of outcome valence is modulated by motivational salience.

IntroductionPediatric radial neck and head fractures are rare, accounting for only 1% of all fractures in children. The aim of this study is to describe the management and results of the respective fracture types and different injury characteristics.Materials and methodsThis study performs a retrospective data analysis of 100 consecutive patients with a fracture of the proximal radius treated in a single high-volume pediatric trauma center.ResultsOne hundred patients [mean age 7.5 years (1–15)] were documented with a fracture of the proximal radius between 3/2011 and 12/2019. The gender distribution was 62 girls and 38 boys. Twenty-seven patients had concomitant injuries. Conservative treatment was performed in 63 patients (Judet I = 27; II = 30; III = 6; Mason I = 2) using an above-the-elbow cast for 21 days (6–35). Surgical treatment was performed in 37 patients (Judet II = 3; III = 22; IV = 5; V = 7) using elastic stable intramedullary nailing (ESIN). Open reduction was necessary in five cases, and additional immobilization was performed in 32 cases. Six complications occurred: loss of implant stability (n = 2), healing in malalignment, pseudarthrosis, radioulnar synostosis, and a persisting hypoesthesia at the thumb. As a result, two ESIN osteosynthesis were revised, and one radial head resection was performed. Loss of movement was seen in 11% of cases, overall Mayo elbow performance index (MEPI) was 99.8 (90–100), and none of the patients experienced negative impacts on activities of daily life.ConclusionsProximal radial fractures occur predominately without dislocation. Good results are obtained with conservative treatment throughout. In cases with displacement exceeding growth-related correction, ESIN is the undisputed treatment of choice. Open surgery and long immobilization periods should be avoided whenever possible.

Learning an association does not always succeed on the first attempt. Previous studies associated increased error signals in posterior medial frontal cortex with improved memory formation. However, the neurophysiological mechanisms that facilitate post-error learning remain poorly understood. To address this gap, participants performed a feedback-based association learning task and a 1-back localizer task. Increased hemodynamic responses in posterior medial frontal cortex were found for internal and external origins of memory error evidence, and during post-error encoding success as quantified by subsequent recall of face-associated memories. A localizer-based machine learning model displayed a network of cognitive control regions, including posterior medial frontal and dorsolateral prefrontal cortices, whose activity was related to face-processing evidence in the fusiform face area. Representation strength was higher during failed recall and increased during encoding when subsequent recall succeeded. These data enhance our understanding of the neurophysiological mechanisms of adaptive learning by linking the need for learning with increased processing of the relevant stimulus category. Using single-trial analysis in fMRI, this study shows that activity in brain areas associated with error monitoring and cognitive control differentiates between items that are later remembered correctly vs those where mistakes persist.

The ability to calibrate learning according to new information is a fundamental component of an organism’s ability to adapt to changing conditions. Yet, the exact neural mechanisms guiding dynamic learning rate adjustments remain unclear. Catecholamines appear to play a critical role in adjusting the degree to which we use new information over time, but individuals vary widely in the manner in which they adjust to changes. Here, we studied the effects of a low dose of methamphetamine (MA), and individual differences in these effects, on probabilistic reversal learning dynamics in a within-subject, double-blind, randomized design. Participants first completed a reversal learning task during a drug-free baseline session to provide a measure of baseline performance. Then they completed the task during two sessions, one with MA (20 mg oral) and one with placebo (PL). First, we showed that, relative to PL, MA modulates the ability to dynamically adjust learning from prediction errors. Second, this effect was more pronounced in participants who performed moderately low at baseline. These results present novel evidence for the involvement of catecholaminergic transmission on learning flexibility and highlights that baseline performance modulates the effect of the drug.

PurposeESIN (elastic stable intramedullary nailing) is considered the gold standard for various pediatric fractures. The aim of this study was to analyze the incidence and type of complications during or after TEN (titanium elastic nail) removal.MethodsA retrospective data analysis was performed. Metal removal associated complications and preoperative extraosseous length/outlet angle of TENs as possible causes of complications were assessed.ResultsThe complication rate in 384 TEN removals was 3.1% (n = 12). One major complication (rupture of M. extensor pollicis brevis) was documented. One refracture at the forearm occurred, however, remodeling prior TEN removal was completed. Ten minor complications were temporary or without irreversible restrictions (3 infections, 5 scaring/granuloma, 2 temporary paraesthesia).In 38 cases (16 forearms, 10 femora, 9 humeri, 3 lower legs), intra-operative fluoroscopy had to be used to locate the implants. In patients with forearm fractures, extraosseous implant length was relatively shorter than in cases without fluoroscopy (p = 0.01), but outlet angle of TENs was not significantly different in these two groups (28.5° vs 25.6°). In patients with femur fractures, extraosseous implant length and outlet angle were tendentially shorter, respectively, lower, but this did not reach statistical significance.ConclusionRemoval of TENs after ESIN is a safe procedure with a low complication rate. Technically inaccurate TEN implantation makes removal more difficult and complicated. To prevent an untimely removal and patient discomfort, nail ends must be exactly positioned and cut. Intraoperative complications may be minimized with removal of TENs before signs of overgrowth.EvidenceLevel III, retrospective.

BackgroundWe conducted a monthly epidemiological survey in Germany to detect the prevalence of volvulus without malrotation (VWM) in very low birthweight (VLBW) infants and to identify factors for a better distinction between this rare and life-threatening event and other acute abdominal diseases in preterm infants.MethodsThroughout 2014 and 2015, every paediatric department in Germany was asked to report cases of VWM in infants with birth weights <1500 g to the Surveillance Unit for Rare Paediatric Conditions in Germany. Hospitals reporting a case were asked to return an anonymised questionnaire and discharge letter.ResultsOf 36 cases reported, detailed information was submitted on 29, with 26 meeting entry criteria. With 9896 and 10 140 VLBW infants born in Germany in 2014 and 2015, respectively, we estimated a prevalence of 1.52/1000 VLBW infants for 2014 and 1.08/1000 in 2015. No specific early symptom could be determined. 10% died, and 21% of infants developed short bowel syndrome. Calculated from all verified VWM arise death in 8% and a short bowel syndrome in 15%.ConclusionVWM is a rare source of acute abdomen in VLBW infants. No specific signs and symptoms potentially facilitating an early recognition of VWM could be found from this survey. Because the rates of death and short bowel syndrome are high, VWM should always be considered early in an acute abdomen in a VLBW infant.

Background Total colonic aganglionosis (TCA) is a rare variant of Hirschsprung’s disease occurring in 3–10% of the cases. Only few studies reported the long-term clinical and metabolic outcomes of patients with TCA. The aim of this study was to evaluate the functional and metabolic long-term outcomes of children undergoing surgical treatment for TCA. Methods A 15-year retrospective study was performed. Blood chemistry tests and stool analysis performed at the last follow-up visit were recorded. Height and weight development were assessed using the corresponding percentiles for age. Faecal continence and quality of life were evaluated using a detailed questionnaire. Results Eleven patients were included in the study. The median age at surgery was 6 months (range: 3–72 months). After histological confirmation, all patients underwent a total colectomy. Ileoanal anastomosis ( n  = 6), ileorectal anastomosis ( n  = 1), J-pouch ( n  = 1) and Duhamel procedure ( n  = 3) were performed. Temporary ileostomy was closed after a median of 8 weeks in 10/11 patients. After a median follow-up of 78 months (range: 27–199 months), all evaluated patients were continent. Height and weight were appropriate for age in only 5 patients. Vitamin B12 and folic acid serum levels were normal in all examined patients. Ten patients had normal hemoglobin serum levels. Seven patients had low transferrin saturation in serum. Hemoccult tests were negative in all examined patients. Despite complex postoperative courses in some cases, patients and parents showed good overall satisfaction in terms of quality of life. Conclusion The majority of patients reported a good quality of life. This can result from the adaptation of the patients to certain disease states. The failure to thrive seems to be related with the extent of aganglionosis. The inclusion of these patients in interdisciplinary long-term follow-up care, in which pediatric surgeons, gastroenterologists, and dieticians are involved, is essential.