Certified Registered Nurse Anesthetist Performance and Perceptions: Use of a Handheld, Computerized, Decision Making Aid During Critical Events in a High-fidelity Human Simulation Environment

With the increasing focus on patient safety and human error, understanding how practitioners make decisions during critical incidents is important. Despite the move towards evidence-based practice, research shows that much decision making is based on intuition and heuristics (“rules of thumb”). The purpose of this study was to examine and evaluate the methodologic feasibility of a strategy for comparing traditional cognition versus the use of algorithms programmed on a personal digital assistant (FDA) in the management of unanticipated critical events by certified registered nurse anesthetists (CRNAs). A combined qualitative-quantitative methodology was utilized. The quantitative element consists of a pilot study using a cross-over trial design. Two case scenarios were carried out in a full-scale, high fidelity, simulated anesthesia care delivery environment. Four subjects participated in both scenarios, one without and one with a PDA containing a catalog of approximately 30 events with diagnostic and treatment related information in second scenario. Audio—videotaping of the scenarios allowed for definitive descriptive analysis of items of interest, including time to correct diagnosis and definitive intervention. The qualitative approach consisted of a phenomenological investigation of problem solving and perceptions of FDA use and the simulation experience by the participants using “think aloud” and retrospective verbal reports, semi-structured group interviews, and written evaluations. Qualitative results revealed that participants found the PDA algorithms useful despite some minor technical difficulties and the simulated environment and case scenarios realistic, but also described feelings of expectation, anxiety, and pressure. Problem solving occurred in a hypothetico-deductive manner. More hypotheses were considered when using the PDA. Time to correct diagnosis and treatment varied by scenario, taking less time with the PDA for one but taking longer with the PDA for the other, likely due to differences in pace and intensity of the two scenarios. The methodologic investigation revealed several areas for improvement including more precise control of case scenarios. All participants agreed with the value of using high fidelity simulation, particularly for problem solving of critical events, and provided useful information for more effective utilization of this tool for education and research

Incremental structure building of preverbal PPs in Dutch

Incremental comprehension of head-final constructions can reveal structural attachment preferences for ambiguous phrases. This study investigates how temporarily ambiguous PPs are processed in Dutch verb-final constructions. In De aannemer heeft op het dakterras bespaard/gewerkt ‘The contractor has on the roof terrace saved/worked’, the PP is locally ambiguous between attachment as argument and as adjunct. This ambiguity is resolved by the sentence-final verb. In a self-paced reading task, we manipulated the argument/adjunct status of the PP, and its position relative to the verb. While we found no reading-time differences between argument and adjunct PPs, we did find that transitive verbs, for which the PP is an argument, were read more slowly than intransitive verbs, for which the PP is an adjunct. We suggest that Dutch parsers have a preference for adjunct attachment of preverbal PPs, and discuss our findings in terms of incremental parsing models that aim to minimize costly reanalysis

An electrophysiological investigation of co-referential processes in visual narrative comprehension

Visual narratives make use of various means to convey referential and co-referential meaning, so comprehenders must recognize that different depictions across sequential images represent the same character(s). In this study, we investigated how the order in which different types of panels in visual sequences are presented affects how the unfolding narrative is comprehended. Participants viewed short comic strips while their electroencephalo- gram (EEG) was recorded. We analyzed evoked and induced EEG activity elicited by both full panels (showing a full character) and refiner panels (showing only a zoom of that full panel), and took into account whether they preceded or followed the panel to which they were co-referentially related (i.e., were cataphoric or anaphoric). We found that full panels elicited both larger N300 amplitude and increased gamma-band power compared to refiner panels. Anaphoric panels elicited a sustained negativity compared to cataphoric panels, which appeared to be sensitive to the referential status of the anaphoric panel. In the time-frequency domain, anaphoric panels elicited reduced 8–12 Hz alpha power and increased 45–65 Hz gamma-band power compared to cataphoric panels. These findings are consistent with models in which the processes involved in visual narrative compre- hension partially overlap with those in language comprehension

Effects of structure and meaning on cortical tracking of linguistic units in naturalistic speech

Recent research has established that cortical activity “tracks” the presentation rate of syntactic phrases in continuous speech, even though phrases are abstract units that do not have direct correlates in the acoustic signal. We investigated whether cortical tracking of phrase structures is modulated by the extent to which these structures compositionally determine meaning. To this end, we recorded electroencephalography (EEG) of 38 native speakers who listened to naturally spoken Dutch stimuli in different conditions, which parametrically modulated the degree to which syntactic structure and lexical semantics determine sentence meaning. Tracking was quantified through mutual information between the EEG data and either the speech envelopes or abstract annotations of syntax, all of which were filtered in the frequency band corresponding to the presentation rate of phrases (1.1–2.1 Hz). Overall, these mutual information analyses showed stronger tracking of phrases in regular sentences than in stimuli whose lexical-syntactic content is reduced, but no consistent differences in tracking between sentences and stimuli that contain a combination of syntactic structure and lexical content. While there were no effects of compositional meaning on the degree of phrase-structure tracking, analyses of event-related potentials elicited by sentence-final words did reveal meaning-induced differences between conditions. Our findings suggest that cortical tracking of structure in sentences indexes the internal generation of this structure, a process that is modulated by the properties of its input, but not by the compositional interpretation of its output

Structure-(in)dependent interpretation of phrases in humans and LSTMs

In this study, we compared the performance of a long short-term memory (LSTM) neural network to the behavior of human participants on a language task that requires hierarchically structured knowledge. We show that humans interpret ambiguous noun phrases, such as second blue ball, in line with their hierarchical constituent structure. LSTMs, instead, only do so after unambiguous training, and they do not systematically generalize to novel items. Overall, the results of our simulations indicate that a model can behave hierarchically without relying on hierarchical constituent structure

Hierarchy in language interpretation: Evidence from behavioural experiments and computational modelling

It has long been recognised that phrases and sentences are organised hierarchically, but many computational models of language treat them as sequences of words without computing constituent structure. Against this background, we conducted two experiments which showed that participants interpret ambiguous noun phrases, such as second blue ball, in terms of their abstract hierarchical structure rather than their linear surface order. When a neural network model was tested on this task, it could simulate such “hierarchical” behaviour. However, when we changed the training data such that they were not entirely unambiguous anymore, the model stopped generalising in a human-like way. It did not systematically generalise to novel items, and when it was trained on ambiguous trials, it strongly favoured the linear interpretation. We argue that these models should be endowed with a bias to make generalisations over hierarchical structure in order to be cognitively adequate models of human language

The position of combined medical treatment in acromegaly

Advances in combination medical treatment have offer new perspectives for acromegaly patients with persistent disease activity despite receiving the available medical monotherapies. The outcomes of combination medical treatment may reflect both additive and synergistic effects. This review focuses on combination medical treatment and its current position in acromegaly, based on clinical studies evaluating the efficacy and safety of combined medical treatment(s) and our own experiences with combination therapy. Arch Endocrinol Metab. 2019;63(6):646-52

Soluble Klotho: a possible predictor of quality of life in acromegaly patients

Purpose: Although quality of life (QoL) is improved in patients with acromegaly after disease control, QoL correlates only weakly with traditional biomarkers. Our objective is to investigate a potential relation between the new serum biomarker soluble Klotho (sKlotho), GH and insulin-like growth factor 1 (IGF-