Speed and Accuracy of Static Image Discrimination by Rats

When discriminating dynamic noisy sensory signals, human and primate subjects achieve higher accuracy when they take more time to decide, an effect attributed to accumulation of evidence over time to overcome neural noise. We measured the speed and accuracy of twelve freely behaving rats discriminating static, high contrast photographs of real-world objects for water reward in a self-paced task. Response latency was longer in correct trials compared to error trials. Discrimination accuracy increased with response latency over the range of 500-1200ms. We used morphs between previously learned images to vary the image similarity parametrically, and thereby modulate task difficulty from ceiling to chance. Over this range we find that rats take more time before responding in trials with more similar stimuli. We conclude that rats' perceptual decisions improve with time even in the absence of temporal information in the stimulus, and that rats modulate speed in response to discrimination difficulty to balance speed and accuracy

Sound-Induced Flash Illusion is Resistant to Feedback Training

A single flash accompanied by two auditory beeps tends to be perceived as two flashes (Shams et al. Nature 408:788, 2000, Cogn Brain Res 14:147–152, 2002). This phenomenon is known as ‘sound-induced flash illusion.’ Previous neuroimaging studies have shown that this illusion is correlated with modulation of activity in early visual cortical areas (Arden et al. Vision Res 43(23):2469–2478, 2003; Bhattacharya et al. NeuroReport 13:1727–1730, 2002; Shams et al. NeuroReport 12(17):3849–3852, 2001, Neurosci Lett 378(2):76–81, 2005; Watkins et al. Neuroimage 31:1247–1256, 2006, Neuroimage 37:572–578, 2007; Mishra et al. J Neurosci 27(15):4120–4131, 2007). We examined how robust the illusion is by testing whether the frequency of the illusion can be reduced by providing feedback. We found that the sound-induced flash illusion was resistant to feedback training, except when the amount of monetary reward was made dependent on accuracy in performance. However, even in the latter case the participants reported that they still perceived illusory two flashes even though they correctly reported single flash. Moreover, the feedback training effect seemed to disappear once the participants were no longer provided with feedback suggesting a short-lived refinement of discrimination between illusory and physical double flashes rather than vanishing of the illusory percept. These findings indicate that the effect of sound on the perceptual representation of visual stimuli is strong and robust to feedback training, and provide further evidence against decision factors accounting for the sound-induced flash illusion

Adaptive Sampling of Information in Perceptual Decision-Making

In many perceptual and cognitive decision-making problems, humans sample multiple noisy information sources serially, and integrate the sampled information to make an overall decision. We derive the optimal decision procedure for two-alternative choice tasks in which the different options are sampled one at a time, sources vary in the quality of the information they provide, and the available time is fixed. To maximize accuracy, the optimal observer allocates time to sampling different information sources in proportion to their noise levels. We tested human observers in a corresponding perceptual decision-making task. Observers compared the direction of two random dot motion patterns that were triggered only when fixated. Observers allocated more time to the noisier pattern, in a manner that correlated with their sensory uncertainty about the direction of the patterns. There were several differences between the optimal observer predictions and human behaviour. These differences point to a number of other factors, beyond the quality of the currently available sources of information, that influences the sampling strategy

Collective Animal Behavior from Bayesian Estimation and Probability Matching

Animals living in groups make movement decisions that depend, among other factors, on social interactions with other group members. Our present understanding of social rules in animal collectives is based on empirical fits to observations and we lack first-principles approaches that allow their derivation. Here we show that patterns of collective decisions can be derived from the basic ability of animals to make probabilistic estimations in the presence of uncertainty. We build a decision-making model with two stages: Bayesian estimation and probabilistic matching.
In the first stage, each animal makes a Bayesian estimation of which behavior is best to perform taking into account personal information about the environment and social information collected by observing the behaviors of other animals. In the probability matching stage, each animal chooses a behavior with a probability given by the Bayesian estimation that this behavior is the most appropriate one. This model derives very simple rules of interaction in animal collectives that depend only on two types of reliability parameters, one that each animal assigns to the other animals and another given by the quality of the non-social information. We test our model by obtaining theoretically a rich set of observed collective patterns of decisions in three-spined sticklebacks, Gasterosteus aculeatus, a shoaling fish species. The quantitative link shown between probabilistic estimation and collective rules of behavior allows a better contact with other fields such as foraging, mate selection, neurobiology and psychology, and gives predictions for experiments directly testing the relationship between estimation and collective behavior

Menopausal symptoms assessment among middle age women in Kushtia, Bangladesh

<p>Abstract</p> <p>Background</p> <p>There are few menopausal study data available in South East Asia especially in Bangladesh. This study was conducted in a well populated town named Kushtia, which is located in the western part of Bangladesh.</p> <p>Objectives</p> <p>This study was aimed to document the menopausal-related symptoms among middle age women of Kushtia region of Bangladesh.</p> <p>Methods</p> <p>By using modified MRS (Menopause Rating Scale) questionnaire, 509 women aged 40-70 years were interviewed to document symptoms commonly associated with menopause.</p> <p>Findings</p> <p>The mean age of menopause was 51.14 years. The most prevalent symptoms reported include, feeling tired (92.90%); headache (88.80%); joint and muscular discomfort (76.20%); physical and mental exhaustion (60.90%) and sleeplessness (54.40%) which are followed by depressive mood (37.30%); irritability (36%); dryness of vagina (36%); hot flushes and sweating (35.80%); anxiety (34.20%). However, noted less frequent symptoms were sexual problem (31.20%); cardiac discomfort (19.10%) and bladder problem (12.80%).</p> <p>Conclusions</p> <p>The prevalence of menopausal symptoms found in this study correspond to other studies on Asian women however the prevalence of classical menopausal symptoms of hot flushes and sweating were lower compared to studies on Caucasian women.</p

Team reasoning and the rational choice of payoff-dominant outcomes in games

Standard game theory cannot explain the selection of payoff-dominant outcomes that are best for all players in common-interest games. Theories of team reasoning can explain why such mutualistic cooperation is rational. They propose that teams can be agents and that individuals in teams can adopt a distinctive mode of reasoning that enables them to do their part in achieving Pareto-dominant outcomes. We show that it can be rational to play payoff-dominant outcomes, given that an agent group identifies. We compare team reasoning to other theories that have been proposed to explain how people can achieve payoff-dominant outcomes, especially with respect to rationality. Some authors have hoped that it would be possible to develop an argument that it is rational to group identify. We identify some large—probably insuperable—problems with this project and sketch some more promising approaches, whereby the normativity of group identification rests on morality

Early and Sustained Improvements in Symptoms and Quality of Life with Upadacitinib in Adults and Adolescents with Moderate-to-Severe Atopic Dermatitis:52-Week Results from Two Phase III Randomized Clinical Trials (Measure Up 1 and Measure Up 2)

Background: Atopic dermatitis is a chronic inflammatory disease characterized by increased itch, skin pain, poor sleep quality, and other symptoms that negatively affect patient quality of life. Upadacitinib, an oral selective Janus kinase (JAK) inhibitor with greater inhibitory potency for JAK1 than JAK2, JAK3, or tyrosine kinase 2, is approved to treat moderate-to-severe atopic dermatitis. Objective: We aimed to evaluate the effect of upadacitinib on patient-reported outcomes over 52 weeks in adults and adolescents with moderate-to-severe atopic dermatitis. Methods: Data from two phase III monotherapy trials of upadacitinib (Measure Up 1, NCT03569293; Measure Up 2, NCT03607422) were integrated. Changes in pruritus, pain, other skin symptoms, sleep, quality of life, mental health, and patient impression were evaluated. Patient-reported outcome assessments included the Worst Pruritus Numerical Rating Scale, Patient-Oriented Eczema Measure, Dermatology Life Quality Index, Atopic Dermatitis Symptom Scale, Atopic Dermatitis Impact Scale, Hospital Anxiety and Depression Scale, SCORing Atopic Dermatitis index, Patient Global Impression of Severity, Patient Global Impression of Change, and Patient Global Impression of Treatment. Minimal clinically important differences, achievement of scores representing minimal disease burden, and the change from baseline were evaluated in patients who received upadacitinib through week 52 and in patients who received placebo through week 16. Results: This analysis included 1609 patients (upadacitinib 15 mg, N = 557; upadacitinib 30 mg, N = 567; placebo, N = 485). Baseline demographics and disease characteristics were generally similar across all arms. The proportion of patients treated with upadacitinib reporting improvements in itch increased rapidly by week 1, increased steadily through week 8, and was sustained through week 52. Patients receiving upadacitinib also experienced improvements in pain and other skin symptoms by week 1, which continued through week 16; improvements were maintained through week 52. Patient reports of improved sleep increased rapidly from baseline to week 1, increased steadily through week 32, and were sustained through week 52. Patients experienced quality-of-life improvements through week 8, which were maintained through week 52. By week 1, patients in both upadacitinib groups experienced rapid improvements in emotional state, and by week 12, patients also achieved meaningful improvements in anxiety and depression. Improvements in mental health continued steadily through week 32 and were maintained through week 52. Patients treated with upadacitinib 30 mg generally experienced improvements in patient-reported outcomes earlier than those treated with upadacitinib 15 mg. Through week 16, patients receiving upadacitinib experienced greater improvements versus those receiving placebo in all assessed patient-reported outcomes. Conclusions: Adults and adolescents with moderate-to-severe atopic dermatitis treated with once-daily upadacitinib 15 or 30 mg experienced early improvements in itch, pain, other skin symptoms, sleep, quality of life, and mental health that were sustained through week 52. Clinical Trial Registration: ClinicalTrials.gov identifiers NCT03569293 (13 August 2018) and NCT03607422 (27 July 2018).</p

Playing your pain away: designing a virtual reality physical therapy for children with upper limb motor impairment

Children with upper limb motor impairment often undergo repetitive therapeutic physiotherapy sessions to minimize functional disabilities of the affected area. Even though therapeutic processes can improve functional outcomes and minimize persistent disabilities, patients often neglect to participate fully in physical therapies due to the associated procedural pain. Over recent decades, there has been a growing interest in designing non-pharmacological interventions which aim to minimize pain during physical therapies and improve functional outcomes. Via two interrelated studies, we explored the use of virtual reality (VR) as a tool to provide therapeutic physiotherapy for child patients in an out-patient hospital department. We found that VR is an effective solution for children with upper limb motor impairment undergoing painful therapeutic process within a hospital environment. VR can improve functional disabilities, alleviate perceived pain, reduce the perceived difficulty of rehabilitation exercises, increase exercise duration and produce positive emotions towards the therapy

Karyotype and genome size of Iberochondrostoma almacai (Teleostei, Cyprinidae) and comparison with the sister-species I.lusitanicum

This study aimed to define the karyotype of the recently described Iberian endemic Iberochondrostoma almacai, to revisit the previously documented chromosome polymorphisms of its sister species I.lusitanicum using C-, Ag-/CMA3 and RE-banding, and to compare the two species genome sizes. A 2n = 50 karyotype (with the exception of a triploid I.lusitanicum specimen) and a corresponding haploid chromosome formula of 7M:15SM:3A (FN = 94) were found. Multiple NORs were observed in both species (in two submetacentric chromosome pairs, one of them clearly homologous) and a higher intra and interpopulational variability was evidenced in I.lusitanicum. Flow cytometry measurements of nuclear DNA content showed some significant differences in genome size both between and within species: the genome of I. almacai was smaller than that of I.lusitanicum (mean values 2.61 and 2.93 pg, respectively), which presented a clear interpopulational variability (mean values ranging from 2.72 to 3.00 pg). These data allowed the distinction of both taxa and confirmed the existence of two well differentiated groups within I. lusitanicum: one that includes the populations from the right bank of the Tejo and Samarra drainages, and another that reunites the southern populations. The peculiar differences between the two species, presently listed as “Critically Endangered”, reinforced the importance of this study for future conservation plans