Stochastic parabolic growth promotes coexistence and a relaxed error threshold in RNA-like replicator populations

The RNA world hypothesis proposes that during the early evolution of life, primordial genomes of the first self-propagating evolutionary units existed in the form of RNA-like polymers. Autonomous, non-enzymatic, and sustained replication of such information carriers presents a problem, because product formation and hybridization between template and copy strands reduces replication speed. Kinetics of growth is then parabolic with the benefit of entailing competitive coexistence, thereby maintaining diversity. Here, we test the information-maintaining ability of parabolic growth in stochastic multispecies population models under the constraints of constant total population size and chemostat conditions. We find that large population sizes and small differences in the replication rates favor the stable coexistence of the vast majority of replicator species ('genes'), while the error threshold problem is alleviated relative to exponential amplification. In addition, sequence properties (GC content) and the strength of resource competition mediated by the rate of resource inflow determine the number of coexisting variants, suggesting that fluctuations in building block availability favored repeated cycles of exploration and exploitation. Stochastic parabolic growth could thus have played a pivotal role in preserving viable sequences generated by random abiotic synthesis and providing diverse genetic raw material to the early evolution of functional ribozymes.

Comparing cognition across major transitions using the hierarchy of formal automata

The evolution of cognition can be understood in terms of a few major transitions-changes in the computational architecture of nervous systems that changed what cognitive capacities could be evolved by downstream lineages. We demonstrate how the idea of a major cognitive transition can be modeled in terms of where a system's effective computational architecture falls on the well-studied hierarchy of formal automata (HFA). We then use recent work connecting artificial neural networks to the HFA, which provides a way to make the structure-architecture link in natural systems. We conclude with reflections on the power and the challenges of traditional thinking when applied to neural architectures. This article is categorized under: Cognitive Biology > Evolutionary Roots of Cognition Psychology > Comparative Philosophy > Foundations of Cognitive Science.

Identifying resource-rational heuristics for risky choice

Perfectly rational decision making is almost always out of reach for people because their computational resources are limited. Instead, people may rely on computationally frugal heuristics that usually yield good outcomes. Although previous research has identified many such heuristics, discovering good heuristics and predicting when they will be used remains challenging. Here, we present a theoretical framework that allows us to use methods from machine learning to automatically derive the best heuristic to use in any given situation by considering how to make the best use of limited cognitive resources. To demonstrate the generalizability and accuracy of our method, we compare the heuristics it discovers against those used by people across a wide range of multi-attribute risky choice environments in a behavioral experiment that is an order of magnitude larger than any previous experiments of its type. Our method rediscovered known heuristics, identifying them as rational strategies for specific environments, and discovered novel heuristics that had been previously overlooked. Our results show that people adapt their decision strategies to the structure of the environment and generally make good use of their limited cognitive resources, although their strategy choices do not always fully exploit the structure of the environment. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Complexity-calibrated benchmarks for machine learning reveal when prediction algorithms succeed and mislead

Recurrent neural networks are used to forecast time series in finance, climate, language, and from many other domains. Reservoir computers are a particularly easily trainable form of recurrent neural network. Recently, a "next-generation" reservoir computer was introduced in which the memory trace involves only a finite number of previous symbols. We explore the inherent limitations of finite-past memory traces in this intriguing proposal. A lower bound from Fano's inequality shows that, on highly non-Markovian processes generated by large probabilistic state machines, next-generation reservoir computers with reasonably long memory traces have an error probability that is at least ∼ 60 % higher than the minimal attainable error probability in predicting the next observation. More generally, it appears that popular recurrent neural networks fall far short of optimally predicting such complex processes. These results highlight the need for a new generation of optimized recurrent neural network architectures. Alongside this finding, we present concentration-of-measure results for randomly-generated but complex processes. One conclusion is that large probabilistic state machines-specifically, large ϵ -machines-are key to generating challenging and structurally-unbiased stimuli for ground-truthing recurrent neural network architectures.

The expression of empathy in human's closest relatives, bonobos and chimpanzees: current and future directions

Empathy is a complex, multi-dimensional capacity that facilitates the sharing and understanding of others' emotions. As our closest living relatives, bonobos (Pan paniscus) and chimpanzees (P. troglodytes) provide an opportunity to explore the origins of hominin social cognition, including empathy. Despite certain assumptions that bonobos and chimpanzees may differ empathically, these species appear to overlap considerably in certain socio-emotional responses related to empathy. However, few studies have systematically tested for species variation in Pan empathic or socio-emotional tendencies. To address this, we synthesise the growing literature on Pan empathy to inform our understanding of the selection pressures that may underlie the evolution of hominin empathy, and its expression in our last common ancestor. As bonobos and chimpanzees show overlaps in their expression of complex socio-emotional phenomena such as empathy, we propose that group comparisons may be as or more meaningful than species comparisons when it comes to understanding the evolutionary pressures for such behaviour. Furthermore, key differences, such as how humans and Pan communicate, appear to distinguish how we experience empathy compared to our closest living relatives.

Interdependent behavior only benefits employees from working-class backgrounds when it is both enacted and valued

Social class disparities are pervasive in American society. In higher education, one critical driver of these disparities is the cultural mismatch between the interdependent norms of people from working-class backgrounds and the independent norms that pervade higher education. However, after graduating from college and entering white-collar workplaces, people from working-class backgrounds have frequent opportunities to collaborate in teams-that is, to enact interdependent behavior. Do these opportunities reduce cultural mismatch for people from working-class backgrounds? Across two survey studies and two experiments with college-educated U.S. employees (total N = 2,566), we find that they do not. We theorize and document that this is because there is often a decoupling between enacting interdependent behavior and whether such behavior is valued as part of being a "good" employee. We find that employees from working-class backgrounds only experience a cultural match and its benefits (e.g., sense of fit, high retention intentions) when interdependent behaviors are both enacted and valued. In contrast, when interdependent behaviors are enacted but not valued, employees from working-class backgrounds experience a cultural mismatch. Furthermore, we find that this pattern is unique to employees from working-class backgrounds: Employees from middle-class backgrounds report similar fit and retention regardless of whether there is a coupling of enacted and valued interdependent behavior. Taken together, our results suggest that it is critical to examine multiple elements of culture simultaneously (e.g., both enacted and valued behavior) to fully understand and predict the consequences of cultural (mis)match. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Psychological freedom, rationality, and the naive theory of reasoning

To make sense of the social world, people reason about others' mental states, including whether and in what ways others can form new mental states. We propose that people's judgments concerning the dynamics of mental state change invoke a "naive theory of reasoning." On this theory, people conceptualize reasoning as a rational, semi-autonomous process that individuals can leverage, but not override, to form new rational mental states. Across six experiments, we show that this account of people's naive theory of reasoning predicts judgments about others' ability to form rational and irrational beliefs, desires, and intentions, as well as others' ability to act rationally and irrationally. This account predicts when, and explains why, people judge others as psychologically constrained by coercion and other forms of situational pressure. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Mother of all bonds: Influences on spatial association across the lifespan in capuchins

In humans, being more socially integrated is associated with better physical and mental health and/or with lower mortality. This link between sociality and health may have ancient roots: sociality also predicts survival or reproduction in other mammals, such as rats, dolphins, and non-human primates. A key question, therefore, is which factors influence the degree of sociality over the life course. Longitudinal data can provide valuable insight into how environmental variability drives individual differences in sociality and associated outcomes. The first year of life-when long-lived mammals are the most reliant on others for nourishment and protection-is likely to play an important role in how individuals learn to integrate into groups. Using behavioral, demographic, and pedigree information on 376 wild capuchin monkeys (Cebus imitator) across 20 years, we address how changes in group composition influence spatial association. We further try to determine the extent to which early maternal social environments have downstream effects on sociality across the juvenile and (sub)adult stages. We find a positive effect of early maternal spatial association, where female infants whose mothers spent more time around others also later spent more time around others as juveniles and subadults. Our results also highlight the importance of kin availability and other aspects of group composition (e.g., group size) in dynamically influencing spatial association across developmental stages. We bring attention to the importance of-and difficulty in-determining the social versus genetic influences that parents have on offspring phenotypes. RESEARCH HIGHLIGHTS: Having more maternal kin (mother and siblings) is associated with spending more time near others across developmental stages in both male and female capuchins. Having more offspring as a subadult or adult female is additionally associated with spending more time near others. A mother's average sociality (time near others) is predictive of how social her daughters (but not sons) become as juveniles and subadults (a between-mother effect). Additional variation within sibling sets in this same maternal phenotype is not predictive of how social they become later relative to each other (no within-mother effect).

Listening to understand: The role of high-quality listening on speakers' attitude depolarization during disagreements

Disagreements can polarize attitudes when they evoke defensiveness from the conversation partners. When a speaker talks, listeners often think about ways to counterargue. This process often fails to depolarize attitudes and might even backfire (i.e., the Boomerang effect). However, what happens in disagreements if one conversation partner genuinely listens to the other's perspective? We hypothesized that when conversation partners convey high-quality listening-characterized by attention, understanding, and positive intentions-speakers will feel more socially comfortable and connected to them (i.e., positivity resonance) and reflect on their attitudes in a less defensive manner (i.e., have self-insight). We further hypothesized that this process reduces perceived polarization (perceived attitude change, perceived attitude similarity with the listener) and actual polarization (reduced attitude extremity). Four experiments manipulated poor, moderate, and high-quality listening using a video vignette (Study 1) and live interactions (Studies 2-4). The results consistently supported the research hypotheses and a serial mediation model in which listening influences depolarization through positivity resonance and nondefensive self-reflection. Most of the effects of the listening manipulation on perceived and actual depolarization generalized across indicators of attitude strength, specifically attitude certainty and attitude morality. These findings suggest that high-quality listening can be a valuable tool for bridging attitudinal and ideological divides. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

In search of animal normativity: a framework for studying social norms in non-human animals

Social norms - rules governing which behaviours are deemed appropriate or inappropriate within a given community - are typically taken to be uniquely human. Recently, this position has been challenged by a number of philosophers, cognitive scientists, and ethologists, who have suggested that social norms may also be found in certain non-human animal communities. Such claims have elicited considerable scepticism from norm cognition researchers, who doubt that any non-human animals possess the psychological capacities necessary for normative cognition. However, there is little agreement among these researchers about what these psychological prerequisites are. This makes empirical study of animal social norms difficult, since it is not clear what we are looking for and thus what should count as behavioural evidence for the presence (or absence) of social norms in animals. To break this impasse, we offer an approach that moves beyond contested psychological criteria for social norms. This approach is inspired by the animal culture research program, which has made a similar shift away from heavily psychological definitions of 'culture' to become organised around a cluster of more empirically tractable concepts of culture. Here, we propose an analogous set of constructs built around the core notion of a normative regularity, which we define as a socially maintained pattern of behavioural conformity within a community. We suggest methods for studying potential normative regularities in wild and captive primates. We also discuss the broader scientific and philosophical implications of this research program with respect to questions of human uniqueness, animal welfare and conservation.

Research Review: The internalizing paradox - youth anxiety and depression symptoms, psychotherapy outcomes, and implications for research and practice

BACKGROUND

Youth anxiety and depression have long been combined within the empirically derived internalizing syndrome. The two conditions show substantial comorbidity, symptom co-occurrence, and overlap in treatment procedures, but paradoxically diverge in psychotherapy outcomes: strong, positive effects for anxiety and weak effects for depression.

METHODS

Drawing on recent research, we examine candidate explanations for this paradox to help identify strategies for addressing it by improving outcomes for youth depression.

RESULTS

Candidate explanations include that youth depression, compared with youth anxiety, has more varied comorbidities and more heterogeneous symptom combinations, has greater uncertainty regarding mediators and mechanisms of change, is treated with more complex and potentially confusing protocols, and has characteristics that may impede client engagement. Candidate strategies for shrinking the psychotherapy effectiveness gap include personalizing through transdiagnostic modular treatment, simplifying therapy by focusing on empirically supported principles of change, developing effective strategies for engaging family members as intervention allies, using shared decision-making to inform clinical decisions and boost client engagement, capitalizing on youth-friendly technological advances, and shortening and digitizing treatments to enhance their accessibility and appeal.

CONCLUSIONS

Recent advances suggest explanations for the internalizing paradox, which in turn suggest strategies for shrinking the youth anxiety-depression psychotherapy outcome gap; these form an agenda for a promising new era of research.

Reply to Rourk, C. Comment on "Albantakis et al. Computing the Integrated Information of a Quantum Mechanism. Entropy 2023, 25, 449"

In response to a comment by Chris Rourk on our article Computing the Integrated Information of a Quantum Mechanism, we briefly (1) consider the role of potential hybrid/classical mechanisms from the perspective of integrated information theory (IIT), (2) discuss whether the (Q)IIT formalism needs to be extended to capture the hypothesized hybrid mechanism, and (3) clarify our motivation for developing a QIIT formalism and its scope of applicability.

Bioelectrical State of Bacteria Is Linked to Growth Dynamics and Response to Neurotransmitters: Perspectives for the Investigation of the Microbiota-Brain Axis

Inter-cellular communication is mediated by a sum of biochemical, biophysical, and bioelectrical signals. This might occur not only between cells belonging to the same tissue and/or animal species but also between cells that are, from an evolutionary point of view, far away. The possibility that bioelectrical communication takes place between bacteria and nerve cells has opened exciting perspectives in the study of the gut microbiota-brain axis. The aim of this paper is (i) to establish a reliable method for the assessment of the bioelectrical state of two bacterial strains: Bacillus subtilis (B. subtilis) and Limosilactobacillus reuteri (L. reuteri); (ii) to monitor the bacterial bioelectrical profile throughout its growth dynamics; and (iii) to evaluate the effects of two neurotransmitters (glutamate and γ-aminobutyric acid-GABA) on the bioelectrical signature of bacteria. Our results show that membrane potential (Vmem) and the proliferative capacity of the population are functionally linked in B. subtilis in each phase of the cell cycle. Remarkably, we demonstrate that bacteria respond to neural signals by changing Vmem properties. Finally, we show that Vmem changes in response to neural stimuli are present also in a microbiota-related strain L. reuteri. Our proof-of-principle data reveal a new methodological approach for the better understanding of the relation between bacteria and the brain, with a special focus on gut microbiota. Likewise, this approach will open exciting perspectives in the study of the inter-cellular mechanisms which regulate the bi-directional communication between bacteria and neurons and, ultimately, for designing gut microbiota-brain axis-targeted treatments for neuropsychiatric diseases.