Evaluating the neurophysiological evidence for predictive processing as a model of perception

For many years, the dominant theoretical framework guiding research into the neural origins of perceptual experience has been provided by hierarchical feedforward models, in which sensory inputs are passed through a series of increasingly complex feature detectors. However, the long‐standing orthodoxy of these accounts has recently been challenged by a radically different set of theories that contend that perception arises from a purely inferential process supported by two distinct classes of neurons: those that transmit predictions about sensory states and those that signal sensory information that deviates from those predictions. Although these predictive processing (PP) models have become increasingly influential in cognitive neuroscience, they are also criticized for lacking the empirical support to justify their status. This limited evidence base partly reflects the considerable methodological challenges that are presented when trying to test the unique predictions of these models. However, a confluence of technological and theoretical advances has prompted a recent surge in human and nonhuman neurophysiological research seeking to fill this empirical gap. Here, we will review this new research and evaluate the degree to which its findings support the key claims of PP

Intracystic papillary carcinoma in a male as a rare presentation of breast cancer: a case report and literature review

<p>Abstract</p> <p>Introduction</p> <p>The term "intracystic papillary ductal carcinoma <it>in situ</it>" has recently changed and is now more appropriately referred to "intracystic papillary carcinoma". Intracystic papillary carcinoma in men is an extremely rare disease with only a few case presentations published in the literature so far.</p> <p>Case presentation</p> <p>We discuss a case of a 44-year-old Caucasian man with an intracystic papillary carcinoma treated with simple mastectomy, sentinel lymph-node biopsy and contralateral risk-reducing mastectomy. These were followed by adjuvant radiotherapy of the breast.</p> <p>Conclusion</p> <p>Triple assessment (i.e. clinical examination and radiological and histological assessment) with a high level of clinical suspicion is necessary to diagnose intracystic papillary carcinoma in men due to its rarity. Furthermore, genetic testing and risk-reducing mastectomy should also be considered in cases of a strong family history for male breast cancer.</p

An electrophysiological signal that precisely tracks the emergence of error awareness

Recent electrophysiological research has sought to elucidate the neural mechanisms necessary for the conscious awareness of action errors. Much of this work has focused on the error positivity (Pe), a neural signal that is specifically elicited by errors that have been consciously perceived. While awareness appears to be an essential prerequisite for eliciting the Pe, the precise functional role of this component has not been identified. Twenty-nine participants performed a novel variant of the Go/No-go Error Awareness Task (EAT) in which awareness of commission errors was indicated via a separate speeded manual response. Independent component analysis (ICA) was used to isolate the Pe from other stimulus- and response-evoked signals. Single-trial analysis revealed that Pe peak latency was highly correlated with the latency at which awareness was indicated. Furthermore, the Pe was more closely related to the timing of awareness than it was to the initial erroneous response. This finding was confirmed in a separate study which derived IC weights from a control condition in which no indication of awareness was required, thus ruling out motor confounds. A receiver-operating-characteristic (ROC) curve analysis showed that the Pe could reliably predict whether an error would be consciously perceived up to 400 ms before the average awareness response. Finally, Pe latency and amplitude were found to be significantly correlated with overall error awareness levels between subjects. Our data show for the first time that the temporal dynamics of the Pe trace the emergence of error awareness. These findings have important implications for interpreting the results of clinical EEG studies of error processing

Uncovering the Neural Signature of Lapsing Attention: Electrophysiological Signals Predict Errors up to 20 s before They Occur

The extent to which changes in brain activity can foreshadow human error is uncertain yet has important theoretical and practical implications. The present study examined the temporal dynamics of electrocortical signals preceding a lapse of sustained attention. Twenty-one participants performed a continuous temporal expectancy task, which involved continuously monitoring a stream of regularly alternating patterned stimuli to detect a rarely occurring target stimulus whose duration was 40% longer. The stimulus stream flickered at a rate of 25 Hz to elicit a steady-state visual-evoked potential (SSVEP), which served as a continuous measure of basic visual processing. Increasing activity in the band (8 –14 Hz) was found beginning20 s before a missed target. This was followed by decreases in the amplitude of two event-related components over a short pretarget time frame: the frontal P3 (3– 4 s) and contingent-negative variation (during the target interval). In contrast, SSVEP amplitude before hits and misses was closely matched, suggesting that the efficacy of ongoing basic visual processing was unaffected. Our results show that the specific neural signatures of attentional lapses are registered in the EEG up to 20 s before an error

Neurochemical enhancement of conscious error awareness

How the brain monitors ongoing behavior for performance errors is a central question of cognitive neuroscience. Diminished awareness of performance errors limits the extent to which humans engage in corrective behavior and has been linked to loss of insight in a number of psychiatric syndromes (e.g., attention deficit hyperactivity disorder, drug addiction). These conditions share alterations in monoamine signaling that may influence the neural mechanisms underlying error processing, but our understanding of the neurochemical drivers of these processes is limited.Weconducted a randomized, double-blind, placebo-controlled, cross-over design of the influence of methylphenidate, atomoxetine, and citalopram on error awareness in 27 healthy participants. The error awareness task, a go/no-go response inhibition paradigm, was administered to assess the influence of monoaminergic agents on performance errors during fMRI data acquisition. A single dose of methylphenidate, but not atomoxetine or citalopram, significantly improved the ability of healthy volunteers to consciously detect performance errors. Furthermore, this behavioral effect was associated with a strengthening of activation differences in the dorsal anterior cingulate cortex and inferior parietal lobe during the methylphenidate condition for errors made with versus without awareness. Our results have implications for the understanding of the neurochemical underpinnings of performance monitoring and for the pharmacological treatment of a range of disparate clinical conditions that are marked by poor awareness of errors

CDC Botswana : sharing another partnership success

CDC Botswana, in partnership with the Ministry of Health since 1995--for a safer, healthier Botswana.Publication date from document properties.CDCBotswanaSharesSuccess_19_07_12.pd

RandomiSed clinical trial assessing Use of an anti-inflammatoRy aGent in attenUating peri-operatiVe inflAmmatioN in non-meTastatic colon cancer – the S.U.R.G.U.V.A.N.T. trial

Background: Peri-operative inflammation has been extensively highlighted in cancer patients as detrimental. Treatment strategies to improve survival for cancer patients through targeting peri-operative inflammation have yet to be devised. Methods: We conducted a multi-centre, randomised controlled clinical trial using Taurolidine in non-metastatic colon cancer patients. Patients were randomly assigned to receive Taurolidine or a placebo. The primary endpoint for the study was the mean difference in day 1 IL-6 levels. Secondary clinical endpoints included rates of post-operative infections and tumor recurrence. Results: A total of 293 patients were screened for trial inclusion. Sixty patients were randomised. Twenty-eight patients were randomised to placebo and 32 patients to Taurolidine. IL-6 levels were equivalent on day 1 post-operatively in both groups. However, IL-6 levels were significantly attenuated over the 7 day study period in the Taurolidine group compared to placebo (p = 0.04). In addition, IL-6 levels were significantly lower at day 7 in the Taurolidine group (p = 0.04). There were 2 recurrences in the placebo group at 2 years and 1 in the Taurolidine group. The median time to recurrence was 19 months in the Placebo group and 38 months in the Taurolidine group (p = 0.27). Surgical site infection was reduced in the Taurolidine treated group (p = 0.09). Conclusion: Peri-operative use of Taurolidine significantly attenuated circulating IL-6 levels in the initial 7 day post-operative period in a safe manner. Future studies are required to establish the impact of IL-6 attenuation on survival outcomes in colon cancer. Trial registration: The trial was registered with EudraCT (year = 2008, registration number = 005570–12) and ISRCTN (year = 2008, registration number = 77,829,558)

'I don't think I ever had food poisoning' : A practice-based approach to understanding foodborne disease that originates in the home

© 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).Food stored, prepared, cooked and eaten at home contributes to foodborne disease which, globally, presents a significant public health burden. The aim of the study reported here was to investigate, analyse and interpret domestic kitchen practices in order to provide fresh insight about how the domestic setting might influence food safety. Using current theories of practice meant the research, which drew on qualitative and ethnographic methods, could investigate people and material things in the domestic kitchen setting whilst taking account of people's actions, values, experiences and beliefs. Data from 20 UK households revealed the extent to which kitchens are used for a range of nonfood related activities and the ways that foodwork extends beyond the boundaries of the kitchen. The youngest children, the oldest adults and the family pets all had agency in the kitchen, which has implications for preventing foodborne disease. What was observed, filmed and photographed was not a single practice but a series of entangled encounters and actions embedded and repeated, often inconsistently, by the individuals involved. Households derived logics and principles about foodwork that represented rules of thumb about 'how things are done' that included using the senses and experiential knowledge when judging whether food is safe to eat. Overall, food safety was subsumed within the practice of 'being' a household and living everyday life in the kitchen. Current theories of practice are an effective way of understanding foodborne disease and offer a novel approach to exploring food safety in the home.Peer reviewedFinal Published versio