Predictive information and error processing : the role of medial-frontal cortex during motor control

We have recently provided evidence that an error-related negativity (ERN), an ERP component generated within medial-frontal cortex, is elicited by errors made during the performance of a continuous tracking task (O.E. Krigolson & C.B. Holroyd, 2006). In the present study we conducted two experiments to investigate the ability of the medial-frontal error system to evaluate predictive error information. In two experiments participants used a joystick to perform a computer-based continuous tracking task in which some tracking errors were inevitable. In both experiments, half of these errors were preceded by a predictive cue. The results of both experiments indicated that an ERN-like waveform was elicited by tracking errors. Furthermore, in both experiments the predicted error waveforms had an earlier peak latency than the unpredicted error waveforms. These results demonstrate that the medial-frontal error system can evaluate predictive error information

Reward positivity elicited by predictive cues

A recent theory holds that a component of the human event-related brain potential called the reward positivity reflects a reward prediction error signal. We investigated this idea in gambling-like task in which, on each trial, a visual stimulus predicted a subsequent rewarding or nonrewarding outcome with 80% probability. Consistent with earlier results, we found that the reward positivity was larger to unexpected than to expected outcomes. In addition, we found that the predictive cues also elicited a reward positivity, as proposed by the theory. These results indicate that the reward positivity reflects the initial assessment of whether a trial will end in success or failure and the reappraisal of that information once the outcome actually occurs. NeuroReport 22:249-252 (C) 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins

Electroencephalographic evidence of vector inversion in antipointing

Mirror-symmetrical reaching movements (i.e., antipointing) produce a visual-field-specific pattern of endpoint bias consistent with a perceptual representation of visual space (Heath et al. in Exp Brain Res 192:275-286, 2009a; J Mot Behav 41:383-392 2009b). The goal of the present investigation was to examine the concurrent behavioural and event-related brain potentials (ERP) of pro- and antipointing to determine whether endpoint bias in the latter task is related to a remapping of the environmental parameters of a target (i.e., vector inversion hypothesis) or a shift of visual attention from a veridical to a cognitively represented target location (i.e., reallocation of attention hypothesis). As expected, results for antipointing-but not propointing-yielded a visual-field-specific pattern of endpoint bias. In terms of the ERP findings, an early component (i.e., the N100) related to the orienting of visuospatial attention was comparable across pro- and antipointing. In contrast, a later occurring component (i.e., the P300) demonstrated a reliable between-task difference in amplitude. Notably, the P300 has been linked to the revision of a 'mental model' when a mismatch is noted between a stimulus and a required task goal (so-called context-updating). Thus, we propose that the between-task difference in the P300 indicates that antipointing is associated with a remapping of a target's veridical location in mirror-symmetrical space (i.e., vector inversion). Moreover, our combined behavioural and ERP findings provide evidence that vector inversion is mediated via perception-based visual networks

When is an error not a prediction error? An electrophysiological investigation

A recent theory holds that the anterior cingulate cortex (ACC) uses reinforcement learning signals conveyed by the midbrain dopamine system to facilitate flexible action selection. According to this position, the impact of reward prediction error signals on ACC modulates the amplitude of a component of the event-related brain potential called the error-related negativity (ERN). The theory predicts that ERN amplitude is monotonically related to the expectedness of the event: It is larger for unexpected outcomes than for expected outcomes. However, a recent failure to confirm this prediction has called the theory into question. In the present article, we investigated this discrepancy in three trial-and-error learning experiments. All three experiments provided support for the theory, but the effect sizes were largest when an optimal response strategy could actually be learned. This observation suggests that ACC utilizes dopamine reward prediction error signals for adaptive decision making when the optimal behavior is, in fact, learnable

Learning to become an expert : reinforcement learning and the acquisition of perceptual expertise

To elucidate the neural mechanisms underlying the development of perceptual expertise, we recorded ERPs while participants performed a categorization task. We found that as participants learned to discriminate computer-generated "blob'' stimuli, feedback modulated the amplitude of the errorrelated negativity (ERN)-an ERP component thought to reflect error evaluation within medial-frontal cortex. As participants improved at the categorization task, we also observed an increase in amplitude of an ERP component associated with object recognition (the N250). The increase in N250 amplitude preceded an increase in amplitude of an ERN component associated with internal error evaluation (the response ERN). Importantly, these electroencephalographic changes were not observed for participants who failed to improve on the categorization task. Our results suggest that the acquisition of perceptual expertise relies on interactions between the posterior perceptual system and the reinforcement learning system involving medial-frontal cortex

Can an Evaluation of Students’ Stress Levels Help us Manage Anxiety During OSCEs and Other Assessment Modalities?

With an increased awareness of mental health issues, in both the student population and the veterinary profession in general, it is important that we obtain a greater understating of the stress experienced by students so as to better prepare them to deal with stress and ameliorate any negative effects it may have on performance. This study aims to characterise various measurements of stress (e.g. HRV, EEG, cortisol, self-report questionnaire) in students within the School of Veterinary Medicine in familiar test modalities, focussing on OSCE assessment. We would also investigate how performance is impacted and what potential factors may influence stress levels. Ultimately, our aim would be to evaluate intervention strategies to assess if students stress levels and performance can be improved

When "It" becomes "Mine": attentional biases triggered by object ownership.

Abstract Previous research has demonstrated that higher-order cognitive processes associated with the allocation of selective attention are engaged when highly familiar self-relevant items are encountered, such as one's name, face, personal possessions and the like. The goal of our study was to determine whether these effects on attentional processing are triggered on-line at the moment self-relevance is established. In a pair of experiments, we recorded ERPs as participants viewed common objects (e.g., apple, socks, and ketchup) in the context of an “ownership” paradigm, where the presentation of each object was followed by a cue indicating whether the object nominally belonged either to the participant (a “self” cue) or the experimenter (an “other” cue). In Experiment 1, we found that “self” ownership cues were associated with increased attentional processing, as measured via the P300 component. In Experiment 2, we replicated this effect while demonstrating that at a visual–perceptual level, spatial attention became more narrowly focused on objects owned by self, as measured via the lateral occipital P1 ERP component. Taken together, our findings indicate that self-relevant attention effects are triggered by the act of taking ownership of objects associated with both perceptual and postperceptual processing in cortex.</jats:p

We are more selfish than we think:The endowment effect and reward processing within the human medial-frontal cortex

Perceived ownership has been shown to impact a variety of cognitive processes: attention, memory, and—more recently—reward processing. In the present experiment we examined whether or not perceived ownership would interact with the construct of value—the relative worth of an object. Participants completed a simple gambling game in which they gambled either for themselves or for another while electroencephalographic data were recorded. In a key manipulation, gambles for oneself or for another were for either small or large rewards. We tested the hypothesis that value affects the neural response to self-gamble outcomes, but not other-gamble outcomes. Our experimental data revealed that while participants learned the correct response option for both self and other gambles, the reward positivity evoked by wins was impacted by value only when gambling for oneself. Importantly, our findings provide additional evidence for a self-ownership bias in cognitive processing and further demonstrate the insensitivity of the medial-frontal reward system to gambles for another. </jats:p

Changes in Cognitive Control Following a Novel Resilience-Focused Nursing Educational Program: An Exploratory Study

Patient care is currently challenged by various factors including stress and nurse fatigue that can negatively impact nurses’ health and patient safety. Emotional exhaustion and burnout among nurses are at an all-time high. Canadian nurses are reporting clinical rates of depression, anxiety, and panic at disproportionately higher rates than other public safety personnel. Innovative educational programs are desperately needed to mitigate stress and relieve distress, which will ultimately promote a healthier and more productive workforce. Little is known about the effectiveness of research informed cognitive control education within a community of practice (COP) to help nurses and nursing students process difficult experiences in order to thrive in stressful work environments. The purpose of this exploratory mixed methods study is to determine if a novel nursing educational program that was embedded in a COP framework leads to changes in cognitive control in a combined group of 16 nurses and nursing students. It included the delivery of 20 hours of community interaction over a 5-week period. Changes in cognitive control were evaluated through electroencephalographic (EEG) measurements before and after completing the course. Participants’ perceived values and priorities for improvement were captured through a focus group. Data demonstrated an increase in cognitive control before and after the COP intervention. The focus group identified nine themes that centered on promoting connection, self-efficacy, non-attachment, accountability, and trauma-informed support, and culture change. Addressing emotional pain through structured relational practice and resilience development provides a larger context for understanding workplace stress, overload, and degraded function. Connecting these disparate stressors clarifies the supporting relationships between cognitive control, personal value, social identity, and spiritual purpose. Resilience development education within a COP improved cognitive control, promoted an alignment with personal values, buffered participants from workplace stress, and empowered them to carry their learnings as change agents in healthcare. The study was limited by a small sample size and a relatively homogenous population. Further research is needed to examine the impact of evidence-informed and resilience-focused COP on patient care, safety, and costs. Résumé Les soins aux patients sont touchés par divers facteurs, dont le stress et la fatigue des infirmières, qui pourraient avoir un impact négatif sur la santé des infirmières et la sécurité des patients. La prévalence de l’épuisement émotionnel et professionnel chez les infirmières n’a jamais été aussi élevée. Les infirmières canadiennes présentent des taux cliniques de dépression, de troubles d’anxiété et de panique disproportionnellement plus élevés que les autres employés de la sécurité publique. Des programmes éducatifs novateurs sont indispensables pour atténuer le stress et soulager la détresse; ils favoriseront, à terme, une main‑d’œuvre en meilleure santé et plus productive. Nous savons peu de choses sur l’efficacité de l’enseignement du contrôle cognitif fondé sur la recherche au sein d’une communauté de pratique (CDP) afin d’aider les infirmières et les étudiantes en sciences infirmières à surmonter les expériences difficiles et à s’épanouir dans un environnement de travail stressant. L’objectif de cette étude exploratoire à méthodologie mixte était de déterminer si un nouveau programme éducatif en sciences infirmières intégré dans un cadre de communauté de pratique pouvait améliorer le contrôle cognitif d’un groupe combiné de 16 infirmières et étudiantes en sciences infirmières. Le programme comprenait 20 heures d’interactions en communauté de pratique sur une période de 5 semaines. Les changements du contrôle cognitif ont été évalués par des mesures électroencéphalographiques (EEG) avant et après la formation. Les valeurs perçues par les participantes ainsi que les principales améliorations ont été recensées lors d’un groupe de discussion. Les résultats ont montré une augmentation du contrôle cognitif avant et après l’intervention en communauté de pratique. Le groupe de discussion a fait ressortir neuf thèmes axés sur la promotion des relations, de l’auto-efficacité, du non-attachement, de la responsabilité, du soutien adapté aux traumatismes vécus et du changement de culture. Le traitement de la souffrance émotionnelle par une pratique relationnelle structurée et le renforcement de la résilience offrent une perspective élargie qui permet de comprendre le stress au travail, la surcharge et la détérioration des rôles. La mise en relation de ces facteurs de stress variés permet de mieux comprendre les liens de soutien entre le contrôle cognitif, les valeurs personnelles, l’identité sociale et le but spirituel. L’enseignement du renforcement de la résilience dans le cadre d’une communauté de pratique a permis d’améliorer le contrôle cognitif, de favoriser l’adéquation avec les valeurs personnelles, de protéger les participantes du stress professionnel et de leur donner les moyens de transmettre leurs connaissances en tant qu’agentes de changement dans le domaine des soins de santé. Les limites de l’étude sont tracées par un échantillon de petite taille et une population relativement homogène. D’autres recherches seront nécessaires pour examiner les retombées de la communauté de pratique fondée sur des données probantes et axée sur la résilience sur le plan des soins aux patients, de la sécurité et des coûts