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Culture – the totality of traditions acquired in a community by social learning from others – has increasingly been found to be pervasive not only in humans but in many animals’ lives, with profound implications for comparative cognitive science as well as evolutionary biology, anthropology and conservation (Aplin, 2019; Brakes et al., 2019; Whiten, 2011; Whiten, 2017a; Whiten et al., 2017). Compared to individual learning, learning from experienced others can more safely and efficiently assimilate the wisdom already accumulated in those individuals.

Abstract The scale of cumulative cultural evolution (CCE) is a defining characteristic of humans. Despite marked scientific interest in CCE, the cognitive underpinnings supporting its development remain understudied. We examined the role cognitive flexibility plays in CCE by studying U.S. children’s (N = 167, 3–5-year-olds) propensity to relinquish an inefficient solution to a problem in favor of a more efficient alternative, and whether they would resist reverting to earlier versions. In contrast to previous work with chimpanzees, most children who first learned to solve a puzzlebox in an inefficient way switched to an observed, more efficient alternative. However, over multiple task interactions, 85% of children who switched reverted to the inefficient method. Moreover, almost all children in a control condition (who first learned the efficient method) switched to the inefficient method. Thus, children were keen to explore an alternative solution but, like chimpanzees, are overall conservative in reverting to their first-learned one.

Abstract A central need for neurodegenerative diseases is to find curative drugs for the many clinical subtypes, the causative gene for most cases being unknown. This requires the classification of disease cases at the genetic and cellular level, an understanding of disease aetiology in the subtypes and the development of phenotypic assays for high throughput screening of large compound libraries. Herein we describe a method that facilitates these requirements based on cell morphology that is being increasingly used as a readout defining cell state. In patient-derived fibroblasts we quantified 124 morphological features in 100,000 cells from 15 people with two genotypes (SPAST and SPG7) of Hereditary Spastic Paraplegia (HSP) and matched controls. Using machine learning analysis, we distinguished between each genotype and separated them from controls. Cell morphologies changed with treatment with noscapine, a tubulin-binding drug, in a genotype-dependent manner, revealing a novel effect on one of the genotypes (SPG7). These findings demonstrate a method for morphological profiling in fibroblasts, an accessible non-neural cell, to classify and distinguish between clinical subtypes of neurodegenerative diseases, for drug discovery, and potentially for biomarkers of disease severity and progression.

Background: Swallowing impairment (dysphagia) and tracheostomy coexist. Research in this area has often provided an overview of dysphagia management as a whole, but there is limited information pertaining to specific dysphagia therapy in the tracheostomy population. The aim of this scoping review is to provide a detailed exploration of the literature with regard to dysphagia therapeutic interventions in adults with a tracheostomy. The scoping review will describe current evidence and thus facilitate future discussions to guide clinical practice. Methods: A scoping review using the Joanna Briggs Institute and Preferred Reporting Items for Systematic Reviews guideline will be used. Ten electronic databases from inception to December 2023 and grey literature will be searched. From identified texts forward and backward citation chasing will be completed. Data extraction will compose of population demographics, aetiology and dysphagia therapy (type, design, dose and intensity). A number of citations and papers included in the scoping review will be presented visually. Discussion: The scoping review aims to expand upon the existing literature in this field. A detailed description of the evidence is required to facilitate clinical discussions and develop therapeutic protocols in a tracheostomised population. The results of this scoping review will support future research in dysphagia therapy and provide the basis for the development of best practice guidelines. What this paper adds: What is already known on this subject: There is an abundance of evidence available regarding dysphagia therapy targeting impairments of the swallowing sequence in a variety of populations including stroke, head and neck cancer, progressive neurological conditions and critical illness. However, there is a paucity in the literature with regard to identifying dysphagia therapy for adults with a tracheostomy. What this study adds: The study protocol aims to describe the methodological features that need to be extracted from existing studies to outline dysphagia therapy for adults with a tracheostomy. To the researchers' knowledge, this is the first study protocol to describe the methodological features of dysphagia therapy for people with a tracheostomy from the literature using a standardised approach (Joanna Briggs Institute and Preferred Reporting Items for Systematic Reviews and Meta‐Analyses [PRISMA] guideline). This will ensure that the protocol is replicable for other researchers to use and demonstrates transparency in research methods. What are the clinical implications of this work?: The development of a robust protocol is necessary in order to facilitate the scoping review to describe the current evidence and thus facilitate future discussions to guide clinical practice for speech and language therapists working with adults who have a tracheostomy and dysphagia. The publication of the scoping review protocol allows future clinical researchers in the area of tracheostomy and dysphagia management a blueprint with which to narrow their own research questions and it also enables replicability as the principles of good research practice dictate. [ABSTRACT FROM AUTHOR]

Costly rituals are ubiquitous and adaptive. Yet, little is known about how children develop to acquire them. The current study examined children's imitation of costly rituals. Ninety‐three 4–6 year olds (47 girls, 45% Oceanians, tested in 2022) were shown how to place tokens into a tube to earn stickers, using either a ritualistic or non‐ritualistic costly action sequence. Children shown the ritualistic actions imitated faithfully at the expense of gaining stickers; conversely, those shown the non‐ritualistic actions ignored them and obtained maximum reward. This highlights how preschool children are adept at and motivated to learn rituals, despite significant material cost. This study provides insights into the early development of cultural learning and the adaptive value of rituals in group cognition. [ABSTRACT FROM AUTHOR]

Network optimality has been described in genes, proteins and human communicative networks. In the latter, optimality leads to the efficient transmission of information with a minimum number of connections. Whilst studies show that differences in centrality exist in animal networks with central individuals having higher fitness, network efficiency has never been studied in animal groups. Here we studied 78 groups of primates (24 species). We found that group size and neocortex ratio were correlated with network efficiency. Centralisation (whether several individuals are central in the group) and modularity (how a group is clustered) had opposing effects on network efficiency, showing that tolerant species have more efficient networks. Such network properties affecting individual fitness could be shaped by natural selection. Our results are in accordance with the social brain and cultural intelligence hypotheses, which suggest that the importance of network efficiency and information flow through social learning relates to cognitive abilities.

Abstract Soluble aggregates of amyloid-β (Aβ) have been associated with neuronal and synaptic loss in Alzheimer’s disease (AD). However, despite significant recent progress, the mechanisms by which these aggregated species contribute to disease progression are not fully determined. As the analysis of human cerebrospinal fluid (CSF) provides an accessible window into the molecular changes associated with the disease progression, we characterised soluble aggregates present in CSF samples from individuals with AD, mild cognitive impairment (MCI) and healthy controls using a range of sensitive biophysical methods. We used super-resolution imaging and atomic force microscopy to characterise the size and structure of the aggregates present in CSF and correlate this with their ability to permeabilise lipid membranes and induce an inflammatory response. We found that these aggregates are extremely heterogeneous and exist in a range of sizes, varying both structurally and in their mechanisms of toxicity during the disease progression. A higher proportion of small aggregates of Aβ that can cause membrane permeabilization are found in MCI CSF; in established AD, a higher proportion of the aggregates were larger and more prone to elicit a pro-inflammatory response in glial cells, while there was no detectable change in aggregate concentration. These results show that large aggregates, some longer than 100 nm, are present in the CSF of AD patients and suggest that different neurotoxic mechanisms are prevalent at different stages of AD.

The reciprocal interaction between genetic and cultural evolution is well recognised in humans. Here, Whitehead and colleagues review the growing body of evidence that culture is also a major driver of both neutral and adaptive genetic evolution in non-human animals.

Amyloid beta (Aβ42) peptides form heterogeneous mixtures of aggregates, which are closely linked to Alzheimer’s disease. This study shows how different types of Aβ42 aggregates are associated with distinct mechanisms of toxicity

Summary: Behavioral flexibility is a critical ability allowing animals to respond to changes in their environment. Previous studies have found evidence of inflexibility when captive chimpanzees are faced with changing task parameters. We provided two groups of sanctuary-housed chimpanzees with a foraging task in which solutions were restricted over time. Initially, juice could be retrieved from within a tube by hand or by using tool materials, but effective solutions were then restricted by narrowing the tube, necessitating the abandonment of previous solutions and adoption of new ones. Chimpanzees responded flexibly, but one group increased their use of effective techniques to a greater extent than the other. Tool-composite techniques emerged in both groups, but primarily in the more flexible group. The more flexible group also showed higher rates of socio-positive behaviors at the task. In conjunction, these findings support the hypothesis that social tolerance may facilitate the emergence and spread of novel behaviors.

This study tested the prediction that, with age, children should rely less on familiarity and more on expertise in their selective social learning. Experiment 1 (N = 50) found that 5- to 6-year-olds copied the technique their mother used to extract a prize from a novel puzzle box, in preference to both a stranger and an established expert. This bias occurred despite children acknowledging the expert model's superior capability. Experiment 2 (N = 50) demonstrated a shift in 7- to 8-year-olds toward copying the expert. Children aged 9-10 years did not copy according to a model bias. The findings of a follow-up study (N = 30) confirmed that, instead, they prioritized their own--partially flawed--causal understanding of the puzzle box.

Various deficits in the cognitive functioning of people with autism have been documented in recent years but these provide only partial explanations for the condition. We focus instead on an imitative disturbance involving difficulties both in copying actions and in inhibiting more stereotyped mimicking, such as echolalia. A candidate for the neural basis of this disturbance may be found in a recently discovered class of neurons in frontal cortex, 'mirror neurons' (MNs). These neurons show activity in relation both to specific actions performed by self and matching actions performed by others, providing a potential bridge between minds. MN systems exist in primates without imitative and ‘theory of mind’ abilities and we suggest that in order for them to have become utilized to perform social cognitive functions, sophisticated cortical neuronal systems have evolved in which MNs function as key elements. Early developmental failures of MN systems are likely to result in a consequent cascade of developmental impairments characterised by the clinical syndrome of autism.

New evidence that neighboring communities of bonobos hunt different prey species, despite extensive overlaps in where they live and hunt, is difficult to explain without invoking cultural factors.

How toxic aggregated forms of α-synuclein lead to neurodegeneration is unclear. Here authors use biophysical and cellular imaging methods to show that specific oligomers of α-synuclein exert effects on mitochondria to induce opening of the permeability transition pore, leading to cell death in Parkinson’s disease.