Empathy and error processing

Recent research suggests a relationship between empathy and error processing. Error processing is an evaluative control function that can be measured using post‐error response time slowing and the error‐related negativity (ERN) and post‐error positivity (Pe) components of the event‐related potential (ERP). Thirty healthy participants completed two measures of empathy, the Interpersonal Reactivity Index (IRI) and the Empathy Quotient (EQ), and a modified Stroop task. Post‐error slowing was associated with increased empathic personal distress on the IRI. ERN amplitude was related to overall empathy score on the EQ and the fantasy subscale of the IRI. The Pe and measures of empathy were not related. Results remained consistent when negative affect was controlled via partial correlation, with an additional relationship between ERN amplitude and empathic concern on the IRI. Findings support a connection between empathy and error processing mechanisms.     

Motor and non-motor error and the influence of error magnitude on brain activity

It has been shown that frontal cortical areas increase their activity during error perception and error processing. However, it is not yet clear whether perception of motor errors is processed in the same frontal areas as perception of errors in cognitive tasks. It is also unclear whether brain activity level is influenced by the magnitude of error. For this purpose, we conducted a study in which subjects were confronted with motor and non-motor errors, and had them perform a sensorimotor transformation task in which they were likely to commit motor errors of different magnitudes (internal errors). In addition to the internally committed motor errors, non-motor errors (external errors) were added to the feedback in some trials. We found that activity in the anterior insula, inferior frontal gyrus (IFG), cerebellum, precuneus, and posterior medial frontal cortex (pMFC) correlated positively with the magnitude of external errors. The middle frontal gyrus (MFG) and the pMFC cortex correlated positively with the magnitude of the total error fed back to subjects (internal plus external). No significant positive correlation between internal error and brain activity could be detected. These results indicate that motor errors have a differential effect on brain activity compared with non-motor errors.     

Sensation seeking and error processing

Sensation seeking is defined by a strong need for varied, novel, complex, and intense stimulation, and a willingness to take risks for such experience. Several theories propose that the insensitivity to negative consequences incurred by risks is one of the hallmarks of sensation‐seeking behaviors. In this study, we investigated the time course of error processing in sensation seeking by recording event‐related potentials (ERPs) while high and low sensation seekers performed an Eriksen flanker task. Whereas there were no group differences in ERPs to correct trials, sensation seeking was associated with a blunted error‐related negativity (ERN), which was female‐specific. Further, different subdimensions of sensation seeking were related to ERN amplitude differently. These findings indicate that the relationship between sensation seeking and error processing is sex‐specific.     

Different error types and error processing in spatial stimulus-response-compatibility tasks: behavioural and electrophysiological data

We tested the hypothesis that in spatial stimulus-response-compatibility (SRC) tasks two different error types occur: A noise-induced 'general error' independent of SRC and reaction time and a 'position driven error' in incompatible trials with short RT being driven by the irrelevant stimulus position. A second issue was whether error detection is different for these two types of errors, which should be reflected by differences in the error negativity (Ne), since the Ne is seen as a neural correlate of error detection. To study these issues, we used a Simon- and a spatial Stroop-task. In incompatible (vs. compatible) trials we found more errors and a below chance accuracy in fast responses. Neither the amplitude nor the latency of the Ne were significantly affected by the experimental factors. This pattern of behavioural results supports the above hypothesis of two error types in such tasks. The Ne results indicate that error detection is similar for both types of errors.     

The error threshold

Basic principles underlying the population dynamics of bacteria and viruses are presented, with emphasis on RNA viruses. Concepts reviewed here include fitness, mutant generation, competition, selection, sequence space and the theoretical origins of quasispecies. A "wild-type" virus is no longer viewed as the fittest type, but as the center of gravity of a population landscape. A consequence of quasispecies is the existence of an error threshold for selective competence. The error threshold has a justification in quasispecies theory and lends itself to exploration of strategies to drive viral populations over the error threshold, the central theme of this volume.     

Real-time error detection but not error correction drives automatic visuomotor adaptation

We investigated the role of visual feedback of task performance in visuomotor adaptation. Participants produced novel two degrees of freedom movements (elbow flexion–extension, forearm pronation–supination) to move a cursor towards visual targets. Following trials with no rotation, participants were exposed to a 60° visuomotor rotation, before returning to the non-rotated condition. A colour cue on each trial permitted identification of the rotated/non-rotated contexts. Participants could not see their arm but received continuous and concurrent visual feedback (CF) of a cursor representing limb position or post-trial visual feedback (PF) representing the movement trajectory. Separate groups of participants who received CF were instructed that online modifications of their movements either were, or were not, permissible as a means of improving performance. Feedforward-mediated performance improvements occurred for both CF and PF groups in the rotated environment. Furthermore, for CF participants this adaptation occurred regardless of whether feedback modifications of motor commands were permissible. Upon re-exposure to the non-rotated environment participants in the CF, but not PF, groups exhibited post-training aftereffects, manifested as greater angular deviations from a straight initial trajectory, with respect to the pre-rotation trials. Accordingly, the nature of the performance improvements that occurred was dependent upon the timing of the visual feedback of task performance. Continuous visual feedback of task performance during task execution appears critical in realising automatic visuomotor adaptation through a recalibration of the visuomotor mapping that transforms visual inputs into appropriate motor commands.     

Trial of polyguacyl safety and tolerance

The results of studies of the antiviral and interferon-inducing activity of the synthetic interferon inducer polyguacyl in white mice as well as the results of the study of safety and tolerance of this drug given to human subjects as aerosol and intranasally are presented. Both modes of administration to mice induced production of endogenous interferon, although after intranasal inoculation high interferon titres in the blood serum of the animals were observed for longer periods of time, whereas after aerosol administration interferon disappeared more rapidly. Significant antiviral protection was achieved only by the intranasal administration of the inducer resulting in 84.0% survival of the animals challenged with the mouse-adapted influenza A/Aichi virus. Clinical trials of polyguacyl in human volunteers demonstrated the safety and good tolerance of this drug given both as aerosol and intranasally.     

Race and HIV Clinical Trial Participation

PurposeThis study was designed to examine at the role race/ethnicity plays in human immunodeficiency virus (HIV) clinical trial enrollment.BackgroundHIV clinical trials are vitally important for improving knowledge about medications and their impact on the pathogenesis of HIV/AIDS. African Americans are disproportionately underrepresented in HIV clinical trials.MethodsA 49-item survey was administered to 145 patients at an urban HIV clinic to explore race and HIV clinical trial participation.ResultsStudy participants were 56% Caucasian, 19% other, 16% African American, and 13% Hispanic. Fewer African Americans had been asked to participate in a trial compared to other groups (8% vs 24%) (p < .05). African Americans were less likely to volunteer for a trial compared to Hispanics and Caucasians, but African Americans did not differ significantly in their willingness participate in clinical trials vs other racial groups. In a regression model age, past trial participation, monetary gain, and comfort with the clinical setting predicted willingness to participate in a trial across racial groups (p < .05).DiscussionThere is a strong need to identify strategies to increase African American enrollment in trials. Such strategies need to begin with trial recruiters actively seeking out African Americans for clinical trial enrollment.     

Delusions and prediction error: re-examining the behavioural evidence for disrupted error signalling in delusion formation

Introduction. There is now significant evidence that prediction error signalling is mediated by dopamine in the midbrain, and that dopamine dysfunction is implicated in people experiencing psychotic symptoms, including delusions. There has also been significant theorizing and experimentation concerning the remaining link in this triad, namely that deviant prediction error signalling produces or maintains psychotic symptoms.

Methods. The research supporting the link between prediction error signalling and delusional symptoms was reviewed. Numerous studies indirectly support this link, but only one set of studies claim to directly test this hypothesis by combining three crucial elements: a patient sample, a manipulation of prediction error and neuroimaging. This particular set of studies were examined in detail.

Results. Important methodological limitations in these studies were observed, and a reinterpretation of their data was offered.

Conclusions. Methodological inconsistencies significantly weaken the claims made by these studies, but their data are consistent with current theorizing and they are instructive for future lines of inquiry in this field.     

Genetic susceptibility and mechanisms for refractive error

Refractive errors, myopia and hyperopia, are the most common causes of visual impairment worldwide. Recent advances in genetics have been utilized to identify a wealth of genetic loci believed to contain susceptibility genes for refractive error (RE). The current genetic evidence confirms that RE is influenced by both common and rare variants with a significant environmental component. These studies argue that only by combining genetic and environmental knowledge with in vivo measurements of biological states will it be possible to understand the underlying biology of RE that will lead to novel therapeutic targets and accurate genetic predictions.     

抑郁症诊疗误区与规范化诊治

<正>抑郁症是一种常见的心境障碍,以显著而持久的心境低落为主要临床特征,可伴有相应的思维和行为异常。抑郁症不仅仅是某些读者认为的遇到不良生活事件"想不开"的普通心理问题,它是具有高