Simplicity in Complexity : Explaining Visual Complexity using Deep Segmentation Models

The complexity of visual stimuli plays an important role in many cognitive phenomena, including attention, engagement, memorability, time perception and aesthetic evaluation. Despite its importance, complexity is poorly understood and ironically, previous models of image complexity have been quite complex. There have been many attempts to find handcrafted features that explain complexity, but these features are usually dataset specific, and hence fail to generalise. On the other hand, more recent work has employed deep neural networks to predict complexity, but these models remain difficult to interpret, and do not guide a theoretical understanding of the problem. Here we propose to model complexity using segment-based representations of images. We use state-of-the-art segmentation models, SAM and FC-CLIP, to quantify the number of segments at multiple granularities, and the number of classes in an image respectively. We find that complexity is well-explained by a simple linear model with these two features across six diverse image-sets of naturalistic scene and art images. This suggests that the complexity of images can be surprisingly simple

Current state of antimicrobial stewardship in children’s hospital emergency departments

BACKGROUND Antimicrobial stewardship programs (ASPs) effectively optimize antibiotic use for inpatients; however, the extent of emergency department (ED) involvement in ASPs has not been described. OBJECTIVE To determine current ED involvement in children's hospital ASPs and to assess beliefs and preferred methods of implementation for ED-based ASPs. METHODS A cross-sectional survey of 37 children's hospitals participating in the Sharing Antimicrobial Resistance Practices collaboration was conducted. Surveys were distributed to ASP leaders and ED medical directors at each institution. Items assessed included beliefs regarding ED antibiotic prescribing, ED prescribing resources, ASP methods used in the ED such as clinical decision support and clinical care guidelines, ED participation in ASP activities, and preferred methods for ED-based ASP implementation. RESULTS A total of 36 ASP leaders (97.3%) and 32 ED directors (86.5%) responded; the overall response rate was 91.9%. Most ASP leaders (97.8%) and ED directors (93.7%) agreed that creation of ED-based ASPs was necessary. ED resources for antibiotic prescribing were obtained via the Internet or electronic health records (EHRs) for 29 hospitals (81.3%). The main ASP activities for the ED included production of antibiograms (77.8%) and creation of clinical care guidelines for pneumonia (83.3%). The ED was represented on 3 hospital ASP committees (8.3%). No hospital ASPs actively monitored outpatient ED prescribing. Most ASP leaders (77.8%) and ED directors (81.3%) preferred implementation of ED-based ASPs using clinical decision support integrated into the EHR. CONCLUSIONS Although ED involvement in ASPs is limited, both ASP and ED leaders believe that ED-based ASPs are necessary. Many children's hospitals have the capability to implement ED-based ASPs via the preferred method: EHR clinical decision support. Infect Control Hosp Epidemiol 2017;38:469-475

Detecting and Deterring Manipulation in a Cognitive Hierarchy

Social agents with finitely nested opponent models are vulnerable to manipulation by agents with deeper reasoning and more sophisticated opponent modelling. This imbalance, rooted in logic and the theory of recursive modelling frameworks, cannot be solved directly. We propose a computational framework, $\aleph$-IPOMDP, augmenting model-based RL agents' Bayesian inference with an anomaly detection algorithm and an out-of-belief policy. Our mechanism allows agents to realize they are being deceived, even if they cannot understand how, and to deter opponents via a credible threat. We test this framework in both a mixed-motive and zero-sum game. Our results show the $\aleph$ mechanism's effectiveness, leading to more equitable outcomes and less exploitation by more sophisticated agents. We discuss implications for AI safety, cybersecurity, cognitive science, and psychiatry.Comment: 11 pages, 5 figure

Using Primary Reinforcement to Enhance Translatability of a Human Affect and Decision-Making Judgment Bias Task

Good translatability of behavioral measures of affect (emotion) between human and nonhuman animals is core to comparative studies. The judgment bias (JB) task, which measures "optimistic" and "pessimistic" decision-making under ambiguity as indicators of positive and negative affective valence, has been used in both human and nonhuman animals. However, one key disparity between human and nonhuman studies is that the former typically use secondary reinforcers (e.g., money) whereas the latter typically use primary reinforcers (e.g., food). To address this deficiency and shed further light on JB as a measure of affect, we developed a novel version of a JB task for humans using primary reinforcers. Data on decision-making and reported affective state during the JB task were analyzed using computational modeling. Overall, participants grasped the task well, and as anticipated, their reported affective valence correlated with trial-by-trial variation in offered volume of juice. In addition, previous findings from monetary versions of the task were replicated: More positive prediction errors were associated with more positive affective valence, a higher lapse rate was associated with lower affective arousal, and affective arousal decreased as a function of number of trials completed. There was no evidence that more positive valence was associated with greater "optimism," but instead, there was evidence that affective valence influenced the participants' decision stochasticity, whereas affective arousal tended to influence their propensity for errors. This novel version of the JB task provides a useful tool for investigation of the links between primary reward and punisher experience, affect, and decision-making, especially from a comparative perspective

Reward and punisher experience alter rodent decision-making in a judgement bias task

The influence of affective states on decision-making is likely to be complex. Negative states resulting from experience of punishing events have been hypothesised to generate enhanced expectations of future punishment and 'pessimistic'/risk-averse decisions. However, they may also influence how decision-outcomes are valued. Such influences may further depend on whether decisions at hand are germane to the rewards or punishers that induced the affective state in the first place. Here we attempt to dissect these influences by presenting either many or few rewards or punishers of different types (sucrose vs air-puff; 50 kHz vs 22 kHz ultrasonic vocalisations) to rats, and investigating their subsequent decisions in a judgement bias task that employed sucrose and air-puff as decision outcomes. Rats that received many sucrose pellets prior to testing were more risk-averse than those receiving many air-puffs. Ultrasonic vocalisations did not alter decision-making. Computational analysis revealed a higher weighting of punishers relative to rewards (in agreement with findings from a separate behavioural task) and a bias towards the risk-averse response following pre-test sucrose compared to pre-test air-puff. Thus, in this study reward and punisher manipulation of affective state appeared to alter decision-making by influencing both expectation and valuation of decision-outcomes in a domain-specific way

Dissecting the links between reward and loss, decision-making, and self-reported affect using a computational approach

Links between affective states and risk-taking are often characterised using summary statistics from serial decision-making tasks. However, our understanding of these links, and the utility of decision-making as a marker of affect, needs to accommodate the fact that ongoing (e.g., within-task) experience of rewarding and punishing decision outcomes may alter future decisions and affective states. To date, the interplay between affect, ongoing reward and punisher experience, and decision-making has received little detailed investigation. Here, we examined the relationships between reward and loss experience, affect, and decision-making in humans using a novel judgement bias task analysed with a novel computational model. We demonstrated the influence of within-task favourability on decision-making, with more risk-averse/'pessimistic' decisions following more positive previous outcomes and a greater current average earning rate. Additionally, individuals reporting more negative affect tended to exhibit greater risk-seeking decision-making, and, based on our model, estimated time more poorly. We also found that individuals reported more positive affective valence during periods of the task when prediction errors and offered decision outcomes were more positive. Our results thus provide new evidence that (short-term) within-task rewarding and punishing experiences determine both future decision-making and subjectively experienced affective states

Playground equipment-related extremity fractures in children presenting to US emergency departments, 2006–2016

Background Despite updated playground equipment and improved industry standards, playgrounds remain a common source of childhood injury. Fractures account for 35% of all playground injuries presenting to emergency departments (EDs). We aimed to examine the time trends and epidemiologic patterns of playground equipment-related extremity fractures in children in the United States. Methods We analyzed data from the National Electronic Injury Surveillance System. Children ≤14 years presenting to US emergency departments from 2006 to 2016 with playground equipment-related injuries were included. We used weighted complex survey analysis to describe the epidemiologic patterns and severity of playground equipment-related extremity fractures and Joinpoint linear weighted regression analysis to determine trends in extremity fractures. Results An annual average of 72,889 children were treated in US EDs for playground equipment-related extremity fractures, yielding a national annual incidence rate of 119.2 per 100,000 children. Playground equipment-related extremity fractures accounted for 33.9% of ED presentations and 78.7% of hospitalizations for playground equipment-related injuries. Of patients with playground equipment-related extremity fractures, 11.2% had severe fractures requiring hospitalization. The annual rate of ED visits due to playground equipment-related extremity fractures remained stable (annual rate of change = 0.74, p = 0.14) from 2006 to 2016. Adjusted for age, injuries on monkey bars or climbing gyms were associated with significantly increased odds of extremity fractures in comparison to injuries from other playground equipment (adjusted odds ratio [aOR]: 2.0; 95% CI: 1.9–2.1). Overall, 49.8% of extremity fractures and 54.7% of severe extremity fractures (i.e. those requiring hospitalization) occurred on monkey bars or climbing gyms. Conclusions Despite enhanced playground safety standards, national rates of playground equipment-related extremity fractures have remained stable in the US. Extremity fractures remain the most common type of playground injury presenting to EDs and most commonly occur on monkey bars and climbing gyms

Patients' attitudes and perceptions towards treatment of hypothyroidism in general practice: an in-depth qualitative interview study

Background Suboptimal thyroid hormone replacement is common in patients with hypothyroidism and the behavioural factors underlying this are poorly understood. Aim To explore the attitudes and perceptions of patients to thyroid hormone replacement therapy. Design & setting An in-depth qualitative interview study with patients with hypothyroidism residing in Northumberland, and Tyne and Wear, UK. Method Twenty-seven patients participated, of which 15 patients had thyroid stimulating hormone (TSH) levels within the reference range (0.4–4.0 mU/L) and 12 patients had TSH levels outside the reference range. A grounded theory approach was used to explore and develop emerging themes, which were mapped to the health belief model (HBM). Results Patients generally had a low understanding of their condition or of the consequences of suboptimal thyroid hormone replacement. Patients that had experienced hypothyroid symptoms at initial diagnosis had a better perception of disease susceptibility, and this was reflected in excellent adherence to levothyroxine in this group of patients. The main benefits of optimal thyroid replacement were improved wellbeing and performance. However, patients who remained unwell despite a normal serum TSH level felt that their normal result presented a barrier to further evaluation of their symptoms by their GP

Adolescent Female Text Messaging Preferences to Prevent Pregnancy After an Emergency Department Visit: A Qualitative Analysis

Background: Over 15 million adolescents use the emergency department (ED) each year in the United States. Adolescent females who use the ED for medical care have been found to be at high risk for unintended pregnancy. Given that adolescents represent the largest users of text messaging and are receptive to receiving text messages related to their sexual health, the ED visit represents an opportunity for intervention. Objective: The aim of this qualitative study was to explore interest in and preferences for the content, frequency, and timing of an ED-based text message intervention to prevent pregnancy for adolescent females. Methods: We conducted semistructured, open-ended interviews in one urban ED in the United States with adolescent females aged 14-19 years. Eligible subjects were adolescents who were sexually active in the past 3 months, presented to the ED for a reproductive health complaint, owned a mobile phone, and did not use effective contraception. Using an interview guide, enrollment continued until saturation of key themes. The investigators designed sample text messages using the Health Beliefs Model and participants viewed these on a mobile phone. The team recorded, transcribed, and coded interviews based on thematic analysis using the qualitative analysis software NVivo and Excel. Results: Participants (n=14) were predominantly Hispanic (13/14; 93%), insured (13/14; 93%), ED users in the past year (12/14; 86%), and frequent text users (10/14; 71% had sent or received >30 texts per day). All were interested in receiving text messages from the ED about pregnancy prevention, favoring messages that were “brief,” “professional,” and “nonaccusatory.” Respondents favored texts with links to websites, repeated information regarding places to receive “confidential” care, and focused information on contraception options and misconceptions. Preferences for text message frequency varied from daily to monthly, with random hours of delivery to maintain “surprise.” No participant feared that text messages would violate her privacy. Conclusions: Adolescent female patients at high pregnancy risk are interested in ED-based pregnancy prevention provided by texting. Understanding preferences for the content, frequency, and timing of messages can guide in designing future interventions in the ED