Development and validation of the Interoceptive States Static Images (ISSI) database

Internal bodily signals provide an essential function for human survival. Accurate recognition of such signals in the self, known as interoception, supports the maintenance of homeostasis, and is closely related to emotional processing, learning and decision-making, and mental health. While numerous studies have investigated interoception in the self, the recognition of these states in others has not been examined despite its crucial importance for successful social relationships. This paper presents the development and validation of the Interoceptive States Static Images (ISSI), introducing a validated database of 423 visual stimuli for the study of non-affective internal state recognition in others, freely available to other researchers. Actors were photographed expressing various exemplars of both interoceptive states and control actions. The images went through a two-stage validation procedure, the first involving free-labelling and the second using multiple choice labelling and quality rating scales. Five scores were calculated for each stimulus, providing information about the quality and specificity of the depiction, as well as the extent to which labels matched the intended state/action. Results demonstrated that control action stimuli were more recognisable than internal state stimuli. Inter-category variability was found for the internal states, with some states being more recognisable than others. Recommendations for the utilisation of ISSI stimuli are discussed. The stimulus set is freely available to researchers, alongside data concerning recognisability.

Simulated nature walks improve psychological well-being along a natural to urban continuum

Compared to urban environments, interactions with natural environments have been associated with several health benefits including psychological restoration and improved emotional well-being. However, classifying environments dichotomously as either natural or urban may emphasize between-category differences and minimize potentially important within-category variation (e.g., forests versus fields of crops; neighborhoods versus city centers). Therefore, the current experiment assessed how viewing brief videos of different environments, ranging along a continuum from stereotypically natural to stereotypically urban, influenced subjective ratings of mood, restoration, and well-being. Participants were randomly assigned to one of four video conditions, which depicted a simulated walk through a pine forest, a farmed field, a tree-lined urban neighborhood, or a bustling city center essentially devoid of greenery. Immediately before and after the videos, participants rated their current emotional states. Participants additionally rated the perceived restorativeness of the video. The results supported the idea that the virtual walks differentially influenced affect and perceived restoration, even when belonging to the same nominal category of natural or urban. The pine forest walk significantly improved happiness relative to both urban walks, whereas the farmed field walk did not. The bustling city center walk decreased feelings of calmness compared to all other walks, including the tree-lined neighborhood walk. The walks also differed on two perceived restorativeness measures (daydreaming and being away) in a graded fashion; however, the farmed field walk was found to be less fascinating than all other walks, including both urban walks. Taken together, these results suggest that categorizing environments as “natural versus urban” may gloss over meaningful within-category variability regarding the restorative potential of different physical environments.

Cardiotocographic features in COVID-19 infected pregnant women

Objectives We aimed to evaluate the cardiotocograph (CTG) traces of 224 women infected with novel coronavirus 2019 (COVID-19) and analyze whether changes in the CTG traces are related to the severity of COVID-19. Methods We designed a prospective cohort study. Two-hundred and twenty-four women who had a single pregnancy of 32 weeks or more, and tested positive for SARS-CoV-2 were included. Clinical diagnosis and classifications were made according to the Chinese management guideline for COVID-19 (version 6.0). Patients were classified into categories as mild, moderate, severe and the CTG traces were observed comparing the hospital admission with the third day of positivity. Results There was no statistically significant relationship between COVID-19 severity and CTG category, variability, tachycardia, bradycardia, acceleration, deceleration, and uterine contractility, Apgar 1st and 5th min. Conclusions Maternal COVID-19 infection can cause changes that can be observed in CTG. Regardless of the severity of the disease, COVID-19 infection is associated with changes in CTG. The increase in the baseline is the most obvious change.

Neural Hierarchy of Color Categorization: From Prototype Encoding to Boundary Encoding

A long-standing debate exists on how our brain assigns the fine-grained perceptual representation of color into discrete color categories. Recent functional magnetic resonance imaging (fMRI) studies have identified several regions as the candidate loci of color categorization, including the visual cortex, language-related areas, and non-language-related frontal regions, but the evidence is mixed. Distinct from most studies that emphasized the representational differences between color categories, the current study focused on the variability among members within a category (e.g., category prototypes and boundaries) to reveal category encoding in the brain. We compared and modeled brain activities evoked by color stimuli with varying distances from the category boundary in an active categorization task. The frontal areas, including the inferior and middle frontal gyri, medial superior frontal cortices, and insular cortices, showed larger responses for colors near the category boundary than those far from the boundary. In addition, the visual cortex encodes both within-category variability and cross-category differences. The left V1 in the calcarine showed greater responses to colors at the category center than to those far from the boundary, and the bilateral V4 showed enhanced responses for colors at the category center as well as colors around the boundary. The additional representational similarity analyses (RSA) revealed that the bilateral insulae and V4a carried information about cross-category differences, as cross-category colors exhibited larger dissimilarities in brain patterns than within-category colors. Our study suggested a hierarchically organized network in the human brain during active color categorization, with frontal (both lateral and medial) areas supporting domain-general decisional processes and the visual cortex encoding category structure and differences, likely due to top-down modulation.

Experienced Category Variability Modulates the Impact of Context on Evaluative Judgments

Data from two experiments show that the experienced structure of a category (i.e., as having high vs. low variability) modulates the impact of context on evaluative judgments of individual exemplars. Target objects (unfamiliar in Experiment 1 and familiar in Experiment 2) were primed with positive and negative images while varying the number (Experiment 1) or typicity (Experiment 2) of exemplars known from a category prior to the judgment task. The results show that evaluations of object valence were more influenced by valenced context cues in high than in low variability category conditions. These results are taken as evidence that more varied exemplar-based category representations facilitate context effects on stimulus evaluation.

Testing the effectiveness of mouse tracking in speech perception

Listeners routinely perceive phonetic speech signals which are made up of acoustic detail belonging to multiple continuous physical dimensions (e.g. intensity, frequency, duration), and then discretely map them onto phonological units like phonemes with ease. Traditional accounts of speech perception suggest that listeners achieve this by discarding all non-distinctive (within-category) variability in the signal in favor of discrete phonological representations, resulting in a phenomenon known as categorical perception. However, more recent findings show that listeners do exhibit sensitivity to intra-categorical phonetic detail, for example by investigating on-line measurements from eye-tracking. It is yet unknown whether mouse tracking, a nascent experimental method capable of producing continuous multi-dimensional measurements from motor behavior, can similarly contribute meaningful evidence to research into categorical perception of speech sounds. The present exploratory studies indicate that the effectiveness of the mouse tracking paradigm may be severely limited for such purposes. Here, mouse tracking was unable to replicate previous findings on listener sensitivity to sub-phonemic variability, although a decidedly non-antagonistic replication attempt was made with regards to the design specifics of the paradigm. These findings undermine assumptions about the mapping between cognitive processes and manual response dynamics, questioning the utility of mouse tracking for speech perception research.

Within-trial variability improves rule-based, not information-integration, category learning

Categorization is a critical component of cognition and contributes to many complex processes, including speech perception. High variability within the environment is thought to initially slow learning while increasing the ability to generalize to novel exemplars. However, little is understood about the mechanisms driving this benefit of variability. The current study investigates the effect of pairing within-category variability with response and feedback within single category-learning trials. Participants who learned categories defined by boundaries orthogonal to the category dimensions—rule-based categories—had superior learning and were better able to generalize to novel exemplars when they were trained with within-trial variability compared to when only a single exemplar was presented on each trial. In contrast, participants who learned categories defined by boundaries involving reliance on both category input dimensions—information-integration categories—showed no enhancement of learning from within-category variability. This draws a distinction between overall variability in the acoustic environment and variability more tightly coupled with response and feedback. The influence of variability as experienced within a single trial differs substantially depending on the nature of the category learning challenge. The results have implications for learning speech categories and for further understanding the mechanisms that contribute to auditory category learning.

Bayes, Rationality, and Rashionality

This chapter reviews the main ideas of Bayesian approaches to learning, compared to associationist approaches. It reviews and discusses Bayesian criticisms of associationist learning theory. In particular, Bayesian theorists have argued that associative models fail to represent confidence in belief and update confidence with experience. The chapter discusses whether updating confidence is necessary to capture entrenchment, suspicious coincidence, and category variability effects. The evidence is argued to be somewhat inconclusive at present, as simulated annealing can often suffice. Furthermore, when confidence updating is suggested by the data, the updating suggested by the data may be non-normative, contrary to the Bayesian notion of the learner as an ideal observer. Following Kruschke, learned selective attention is argued to explain many ways in which human learning departs from that of the ideal observer, most crucially including the weakness of backward relative to forward blocking. Other departures from the ideal observer may be due to biological organisms taking into account factors other than belief accuracy. Finally, generative and discriminative learning models are compared. Generative models are argued to be particularly likely when active learning is a possibility and when reversing the observed mappings may be required.