Activity Patterns Research Articles

Nonfrontal Control of Working Memory.

Items held in visual working memory can be quickly updated, replaced, removed, and even manipulated in accordance with current behavioral goals. Here, we use multivariate pattern analyses to identify the patterns of neuronal activity that realize the executive control processes supervising these flexible stores. We find that portions of the middle temporal gyrus and the intraparietal sulcus represent what item is cued for continued memorization independently of representations of the item itself. Importantly, this selection-specific activity could not be explained by sensory representations of the cue and is only present when control is exerted. Our results suggest that the selection of memorized items might be controlled in a distributed and decentralized fashion. This evidence provides an alternative perspective to the notion of "domain general" central executive control over memory function.

Estimating financial integration in Europe: How to separate structural trends from cyclical fluctuations

We construct a new indicator of de facto financial integration for the EU. The resulting indicator is pro-cyclical as it evolves along the cyclical pattern of economic activity in the European Union. It is then appended to a set of relevant financial and macroeconomic variables, within a FAVAR framework, to allow us to separate the impact of cyclical boom-bust shocks from structural integration shocks. Increasing structural financial integration tends to improve risk absorption and reduce income disparities among European countries. However, our analysis suggests that most of the movements in the indicator reflect business cycle dynamics, not proper integration. Given the estimated beneficial effects of stronger structural financial integration, these results highlight the need to develop further policies to foster it in the EU.

Physical activity, problematic gaming behavior, and quality of life prior and during the first 9 months of the COVID-19 pandemic: Findings from a longitudinal study among university students.

Generally, there is limited information on longitudinal trends and the interrelations between physical activity (PA), problematic gaming behavior (PGB), described as a dysfunctional pattern of videogame activities, and quality of life (QoL) based on data that include measurements from both pre- and postpandemic onset. This is also the case for university students. As society faced unprecedented restrictions during this period, these aspects may have developed unfavorably. To examine PA, PGB, and QoL among Norwegian University students prior to and during the initial stages of the pandemic and assess their temporal interrelations. The data are derived from the "Students' Psychological Health Over Time" study (SPOT). Linear mixed models were used to examine the development from January 2020 to November 2020 over three time points for the total sample and across gender. A traditional cross-lagged panel model analysis was used to estimate temporal associations. Age, gender, socioeconomic status, and partner status were included as covariates. PA and QoL decreased linearly over time (Cohen's d = 0.12 and 0.35, respectively), while only male students reported a small reduction in PGB (Cohen's d = 0.03). PA levels decreased considerably more for male students than female students (Cohen's d = 0.17 and 0.09, respectively). There was a small reciprocal negative temporal association between PA and PGB (standardized β = -0.04 and -0.05, respectively). All other temporal associations were not statistically significant in the adjusted analysis. The findings highlight gender-variant negative developments in PA and QoL and suggest a negative reciprocal interrelation between PA and PGB. The findings point to potential adverse health effects that should be taken into account when restrictive pandemic measures are considered.

Pan-cortical 2-photon mesoscopic imaging and neurobehavioral alignment in awake, behaving mice.

The flow of neural activity across the neocortex during active sensory discrimination is constrained by task-specific cognitive demands, movements, and internal states. During behavior, the brain appears to sample from a broad repertoire of activation motifs. Understanding how these patterns of local and global activity are selected in relation to both spontaneous and task-dependent behavior requires in-depth study of densely sampled activity at single neuron resolution across large regions of cortex. In a significant advance toward this goal, we developed procedures to record mesoscale 2-photon Ca2+ imaging data from two novel in vivo preparations that, between them, allow for simultaneous access to nearly all 0f the mouse dorsal and lateral neocortex. As a proof of principle, we aligned neural activity with both behavioral primitives and high-level motifs to reveal the existence of large populations of neurons that coordinated their activity across cortical areas with spontaneous changes in movement and/or arousal. The methods we detail here facilitate the identification and exploration of widespread, spatially heterogeneous neural ensembles whose activity is related to diverse aspects of behavior.

Unimodal activity pattern of stone marten in a Mediterranean island habitat

Unimodal activity pattern of stone marten in a Mediterranean island habitat

Pariah Dog at the Chittagong University Campus: Home Range, Activity Pattern and Breeding

Home range, activity pattern and breeding aspects of the pariah dog (Canis lupus familiaris Linnaeus, 1786) were studied at the Chittagong University Campus in Chittagong of Bangladesh during September 2012 to January 2013. The average home range encircled during daytime by a pack was 10,120 m2. The activity pattern of two dog packs was monitored through scan sampling methods at 15 minutes intervals. The dogs spent their diurnal time in resting (24.5%), sitting and basking (17.1%), standing (2.4%), moving and walking (16.2%), running (17.5%), sleeping (5.3%), feeding, foraging and drinking (6.3%), social behavior (2.9%) and territorial behavior (7.8%). Parturition occurred from September to January and the peak period was in November. The average litter size was 4.7 (range 1-12, n=10). and the overall survival rate of puppies was 2.6 per litter (i.e., 55.32%) up to January. The Chittagong Univ. J. B. Sci. 8(1&2): 21-32, 2013

TAD border deletion at the Kit locus causes tissue-specific ectopic activation of a neighboring gene

Topologically associated domains (TADs) restrict promoter-enhancer interactions, thereby maintaining the spatiotemporal pattern of gene activity. However, rearrangements of the TADs boundaries do not always lead to significant changes in the activity pattern. Here, we investigated the consequences of the TAD boundaries deletion on the expression of developmentally important genes encoding tyrosine kinase receptors: Kit, Kdr, Pdgfra. We used genome editing in mice to delete the TADs boundaries at the Kit locus and characterized chromatin folding and gene expression in pure cultures of fibroblasts, mast cells, and melanocytes. We found that although Kit is highly active in both mast cells and melanocytes, deletion of the TAD boundary between the Kit and Kdr genes results in ectopic activation only in melanocytes. Thus, the epigenetic landscape, namely the mutual arrangement of enhancers and actively transcribing genes, is important for predicting the consequences of the TAD boundaries removal. We also found that mice without a TAD border between the Kit and Kdr genes have a phenotypic manifestation of the mutation — a lighter coloration. Thus, the data obtained shed light on the principles of interaction between the 3D chromatin organization and epigenetic marks in the regulation of gene activity.

Topology of surface electromyogram signals: hand gesture decoding on Riemannian manifolds.

Decoding gestures from the upper limb using noninvasive surface electromyogram (sEMG) signals is of keen interest for the rehabilitation of amputees, artificial supernumerary limb augmentation, gestural control of computers, and virtual/augmented realities. We show that sEMG signals recorded across an array of sensor electrodes in multiple spatial locations around the forearm evince a rich geometric pattern of global motor unit (MU) activity that can be leveraged to distinguish different hand gestures. We demonstrate a simple technique to analyze spatial patterns of muscle MU activity within a temporal window and show that distinct gestures can be classified in both supervised and unsupervised manners. Specifically, we construct symmetric positive definite (SPD) covariance matrices to represent the spatial distribution of MU activity in a time window of interest, calculated as pairwise covariance of electrical signals measured across different electrodes. This allows us to understand and manipulate multivariate sEMG timeseries on a more natural subspace - the Riemannian manifold. Furthermore, it directly addresses signal variability across individuals and sessions, which remains a major challenge in the field. sEMG signals measured at a single electrode lack contextual information such as how various anatomical and physiological factors influence the signals and how their combined effect alters the evident interaction among neighboring muscles. As we show here, analyzing spatial patterns using covariance matrices on Riemannian manifolds allows us to robustly model complex interactions across spatially distributed MUs and provides a flexible and transparent framework to quantify differences in sEMG signals across individuals. The proposed method is novel in the study of sEMG signals and its performance exceeds the current benchmarks while maintaining exceptional computational efficiency.

Brain wide representation of social knowledge.

Understanding how the human brain maps different dimensions of social conceptualizations remains a key unresolved issue. We performed a functional MRI study in which participants were exposed to audio definitions of personality traits and asked to simulate experiences associated with the concepts. Half of the concepts were affective (e.g. empathetic) and the other half were non-affective (e.g. intelligent). Orthogonally, half of the concepts were highly likable (e.g. sincere) and half were socially undesirable (e.g. liar). Behaviourally, we observed that the dimension of social desirability reflected the participant's subjective ratings better than affect. FMRI decoding results showed that both social desirability and affect could be decoded in local patterns of activity through distributed brain regions including the superior temporal, inferior frontal, precuneus and key nodes of the default mode network in posterior/anterior cingulate and ventromedial prefrontal cortex. Decoding accuracy was better for social desirability than affect. A representational similarity analysis further demonstrated that a deep language model significantly predicted brain activity associated with the concepts in bilateral regions of superior and anterior temporal lobe. The results demonstrate a brain wide representation of social knowledge, involving default model network systems that support the multimodal simulation of social experience, with a further reliance on language related preprocessing.

Correlation Between Lifestyle Patterns and Cognitive Function Among Community-Dwelling Older Chinese Adults in the Pre-Dementia Stages: A Latent Class Analysis.

Lifestyle activity engagement is a modifiable factor for cognitive decline. We aimed to identify lifestyle patterns (LPs) among community-dwelling older adults in the pre-dementia stages and to explore the links between LPs, cognitive function, and individual characteristics. 702 older Chinese adults were recruited. Three LPs were identified by latent class analysis: active aging lifestyle pattern (AALP), leisure lifestyle pattern (LLP), and work-centered lifestyle pattern (WLP). AALP refers to participation in various activities that are meaningful to individuals and benefit their well-being. LLP is the pattern of activities aimed at recreation. WLP refers to the LP where individuals are most likely to engage in work-related activities. However, only AALP is protected against mild cognitive impairment (MCI). Multinomial logistic regression models revealed the differences in individual characteristics among participants with different LPs, indicating the importance of tailored intervention strategies. As a protective factor against MCI, AALP should be highlighted in community-based care.

Unravelling epigenetic mechanisms in Cerastoderma edule genome: a comparison of healthy and neoplastic cockles

Cancer is a multifaceted genetic disease characterized by the acquisition of several essential hallmarks. Notably, certain cancers exhibit horizontal transmissibility, observed across mammalian species and diverse bivalves, the latter referred to as hemic neoplasia. Within this complex landscape, epigenetic mechanisms such as histone modifications and cytosine methylation emerge as fundamental contributors to the pathogenesis of these transmissible cancers. Our study delves into the epigenetic landscape of Cerastoderma edule, focusing on whole-genome methylation and hydroxymethylation profiles in heathy specimens and transmissible neoplasias by means of Nanopore long-read sequencing. Our results unveiled a global hypomethylation in the neoplastic specimens compared to their healthy counterparts, emphasizing the role of DNA methylation in these tumorigenic processes. Furthermore, we verified that intragenic CpG methylation positively correlated with gene expression, emphasizing its role in modulating transcription in healthy and neoplastic cockles, as also highlighted by some up-methylated oncogenic genes. Hydroxymethylation levels were significantly more elevated in the neoplastic samples, particularly within satellites and complex repeats, likely related to structural functions. Additionally, our analysis also revealed distinct methylation and activity patterns in retrotransposons, providing additional insights into bivalve neoplastic processes. Altogether, these findings contribute to understanding the epigenetic dynamics of bivalve neoplasias and shed light on the roles of DNA methylation and hydroxymethylation in tumorigenesis. Understanding these epigenetic alterations holds promise for advancing our broader understanding of cancer epigenetics.

Excitable dynamics driven by mechanical feedback in biological tissues

Pulsatory activity patterns, driven by mechanochemical feedback, are prevalent in many biological systems. However, the role of cellular mechanics and geometry in the propagation of pulsatory signals remains poorly understood. Here we present a theoretical framework to elucidate the mechanical origin and regulation of pulsatile activity patterns within excitable multicellular tissues. We show that a simple mechanical feedback at the level of individual cells – activation of contractility upon stretch and subsequent inactivation upon turnover of active elements – is sufficient to explain the emergence of quiescent states, long-range wave propagation, and traveling activity pulse at the tissue-level. We find that the transition between a propagating pulse and a wave is driven by the competition between timescales associated with cellular mechanical response and geometrical disorder in the tissue. This sheds light on the fundamental role of cell packing geometry on tissue excitability and spatial propagation of activity patterns.

Study Roadmap Selection Based on the Thermal Comfort of Street Trees in Summer: A Case Study from a University Campus in China

The intensification of the urban heat island effect, characterized by persistent high temperatures in Chinese cities during summer, has led to notable shifts in urban residents’ activity patterns and travel preferences. Given that street trees, as fundamental components of urban road networks, have significant interaction with residents, it is imperative to investigate their thermal comfort impact. This study aims to enhance the comfortable summer travel experience for urban dwellers. Fujian Agriculture and Forestry University (FAFU) was selected as the case study site, with eight street tree species identified as measurement points. The summer solstice (21 June 2023) served as the representative weather condition. Through monitoring temperature and humidity, the study explored the correlation between street tree species, their characteristic factors, and thermal comfort. Utilizing ENVI-met and ArcGIS, the thermal comfort of campus travel routes was assessed, leading to the development of a summer travel guide based on thermal comfort considerations. The research novelty lies in applying a combined ENVI-met 5.0.2 and ArcGIS 10.8 software approach for modelling and visualizing the microclimate, which enables a more precise analysis of the thermal comfort variations of different campus paths, thus improving the accuracy and applicability of the results in urban planning. The findings reveal several points. (1) Different street trees possess varying capacities to enhance human comfort, with Falcataria falcata and Mangifera indica exhibiting the strongest cooling and humidifying effects, whereas Bauhinia purpurea and Amygdalus persica perform the poorest. Additionally, the research confirms ENVI-met’s scientific accuracy and practicality for microclimate studies. (2) The contribution of street trees to the comfort of campus road travel is primarily determined by the Sky View Factor (SVF), which negatively correlates with cooling and humidifying intensity and positively with thermal comfort. (3) During midday, travel comfort conditions on campus roads are better. Based on the thermal comfort assessment, a summer roadmap was created for the campus. In this case, the campus roads indicated by road A are considered the best travel routes in summer, and the roads indicated by roads B and C are considered alternatives for travelling. This practical application demonstrates how theoretical research results can be translated into practical tools for daily commuting and urban planning. It provides data references and empirical cases for the scientific optimization and enhancement of urban roads.

Association of physical activity pattern and risk of Parkinson’s disease

Increasing evidence suggests an association between exercise duration and Parkinson’s disease. However, no high-quality prospective evidence exists confirming whether differences exist between the two modes of exercise, weekend warrior and equal distribution of exercise duration, and Parkinson’s risk. Hence, this study aimed to explore the association between different exercise patterns and Parkinson’s risk using exercise data from the UK Biobank. The study analyzed data from 89,400 UK Biobank participants without Parkinson’s disease. Exercise data were collected using the Axivity AX3 wrist-worn triaxial accelerometer. Participants were categorized into three groups: inactive, regularly active, and engaged in the weekend warrior (WW) pattern. The relationship between these exercise patterns and Parkinson’s risk was assessed using a multifactorial Cox model. During a mean follow-up of 12.32 years, 329 individuals developed Parkinson’s disease. In a multifactorial Cox model, using the World Health Organization–recommended threshold of 150 min of moderate-to-vigorous physical activity per week, both the active WW group [hazard ratio (HR) = 0.58; 95% confidence interval (CI) = 0.43–0.78; P < 0.001] and the active regular group (HR = 0.44; 95% CI = 0.34–0.57; P < 0.001) exhibited a lower risk of developing Parkinson’s disease compared with the inactive group. Further, no statistically significant difference was observed between the active WW and the active regular groups (HR = 0.77; 95% CI = 0.56–1.05; P = 0.099). In conclusion, in this cohort study, both the WW exercise pattern and an equal distribution of exercise hours were equally effective in reducing Parkinson’s risk.

Supplementation with autologous adipose stem cell-derived mitochondria can be a safe and promising strategy for improving oocyte quality.

In our previous study, we confirmed that the supplementation of vitrified-warmed murine oocytes with autologous adipose stem cell (ASC)-derived mitochondria during intracytoplasmic sperm injection enhances post-fertilization developmental competence in mice. To ensure the safety of this technology, we conducted a thorough study in mice to investigate the potential presence of specific malformations in offspring developed from this approach. A transgenerational comparative analysis was conducted on founder mice from embryos that developed after mitochondrial supplementation, and two subsequent generations. Reproductive performance, body growth rate, histopathological parameters, hematological parameters, daily activity patterns, and daily body temperature changes in male and female mice across these three generations were assessed in comparison to wild-type mice of the same age. Both male and female animals in all three generations showed comparable reproductive performance to the control group. Additionally, body growth rate by the age of 8weeks were found to be comparable to controls across all three generations. Notably, no significant histopathological abnormalities were detected in vital organs, including the brain, heart, liver, kidneys, lungs, ovaries, and testes, in any individuals from the studied cohorts. The blood parameters were consistent with the control data. The continuous monitoring of activity and body temperature changes (both day and night) over a 1-week period revealed a pattern closely resembling that observed in the control animals. Injection of ASC-mitochondria into oocytes may be a promising technique to support developmental potential without causing adverse epigenetic events in the offspring in mice. However, before considering clinical application, additional safety screening using larger animals or non-human primates is essential.

Photostability and photodynamic antimicrobial profile of dye extracts from four (4) plants: prospects for eco-friendly low-cost food disinfection and topical biomedical applications.

In this study, photostability and photodynamic antimicrobial performance of dye extracts from Hibiscus sabdariffa (HS) calyces, Sorghum bicolor (SB) leaf sheaths, Lawsonia inermis (LI) leaves and Curcuma longa (CL) roots were investigated in Acetate-HCl (AH) Buffer (pH 4.6), Tris Base-HCl (TBH) Buffer (pH 8.6), distilled water (dH2O), and Phosphate Buffer Saline (PBS, pH 7.2) using Bacillus subtilis as model for gram positive bacteria, Escherichia coli as model for gram negative bacteria, phage MS2 as model for non-envelope viruses and phage phi6 as model for envelope viruses including SARS CoV-2 which is the causative agent of COVID-19. Our results showed that the photostability of the dye extracts is in the decreasing order of LI > CL > SB > HS. The dye extract-HS is photostable in dH2O but bleaches in buffers-AH, TBH and PBS. The rate of bleaching is higher in AH compared to in TBH and PBS. The bleaching and buffers affected the photodynamic and non-photodynamic antimicrobial activity of the dye extracts. The photodynamic antibacterial activity of the dye extracts is in the decreasing order of CL > HS > LI > SB while the non-photodynamic antibacterial activity is in the decreasing order of LI > CL > HS > SB. The non-photodynamic antiviral activity pattern observed is the same as that of non-photodynamic antibacterial activity observed. However, the photodynamic antiviral activity of the dye extracts is in the decreasing order of CL > LI > HS > SB. Given their performance, the dye extracts maybe mostly suitable for environmental applications including fresh produce and food disinfection, sanitation of hands and contact surfaces where water can serve as diluent for the extracts and the microenvironment is free of salts.

Single trial Bayesian inference by population vector readout in the barn owl's sound localization system.

Bayesian models have proven effective in characterizing perception, behavior, and neural encoding across diverse species and systems. The neural implementation of Bayesian inference in the barn owl's sound localization system and behavior has been previously explained by a non-uniform population code model. This model specifies the neural population activity pattern required for a population vector readout to match the optimal Bayesian estimate. While prior analyses focused on trial-averaged comparisons of model predictions with behavior and single-neuron responses, it remains unknown whether this model can accurately approximate Bayesian inference on single trials under varying sensory reliability, a fundamental condition for natural perception and behavior. In this study, we utilized mathematical analysis and simulations to demonstrate that decoding a non-uniform population code via a population vector readout approximates the Bayesian estimate on single trials for varying sensory reliabilities. Our findings provide additional support for the non-uniform population code model as a viable explanation for the barn owl's sound localization pathway and behavior.

Self-organization of modular activity in immature cortical networks

During development, cortical activity is organized into distributed modular patterns that are a precursor of the mature columnar functional architecture. Theoretically, such structured neural activity can emerge dynamically from local synaptic interactions through a recurrent network with effective local excitation with lateral inhibition (LE/LI) connectivity. Utilizing simultaneous widefield calcium imaging and optogenetics in juvenile ferret cortex prior to eye opening, we directly test several critical predictions of an LE/LI mechanism. We show that cortical networks transform uniform stimulations into diverse modular patterns exhibiting a characteristic spatial wavelength. Moreover, patterned optogenetic stimulation matching this wavelength selectively biases evoked activity patterns, while stimulation with varying wavelengths transforms activity towards this characteristic wavelength, revealing a dynamic compromise between input drive and the network’s intrinsic tendency to organize activity. Furthermore, the structure of early spontaneous cortical activity – which is reflected in the developing representations of visual orientation – strongly overlaps that of uniform opto-evoked activity, suggesting a common underlying mechanism as a basis for the formation of orderly columnar maps underlying sensory representations in the brain.

A step in time: A sequence analysis and choice modelling approach to examine time allocation in individual activities and the role of neighbourhood crime

The Space-Time Budget (STB) method is used to collect spatial and temporal features of an individual’s activities and is an important technique to explore relationships between the environment and crime. This spatial and temporal approach to the study of everyday activity spaces reveals much about victimisation experiences, the relationship between place, time, and perceptions of safety, and where and when offending may occur. Few studies, however, consider the relationship between living in a criminogenic place (neighbourhood crime) and people’s daily activity patterns. Drawing on disaggregate app-based data for 50 participants tracked over a 7-day period, we use sequence analysis to first delineate time allocation to each activity on a minute-by-minute basis. Next, using result from the sequence analysis we introduce the multiple discrete-continuous extreme value (MDCEV) model to understand how neighbourhood crime and socio-demographic characteristics influence individuals’ time allocation to discrete daily activities. Results reveal that neighbourhood drug and violent incidents exert restrictions on an individual’s propensity to spend time outside the home. Females and older people appear more likely to be constrained by the presence of neighbourhood crime (in particular drug and property incidents) as they allocate less time to outdoor activities. The principal utility of the current study is its methodological advancement and the practical insights for urban planning regarding the design of crime prevention strategies to increase guardianship in public places.

Trying harder: how cognitive effort sculpts neural representations during working memory.

While the exertion of mental effort improves performance on cognitive tasks, the neural mechanisms by which motivational factors impact cognition remain unknown. Here, we used fMRI to test how changes in cognitive effort, induced by changes in task difficulty, impacts neural representations of working memory. Participants (both sexes) were precued whether working memory difficulty would be hard or easy. We hypothesized that hard trials demanded more effort as a later decision required finer mnemonic precision. Behaviorally, pupil size was larger and response times were slower on hard compared to easy trials suggesting our manipulation of effort succeeded. Neurally, we observed robust persistent activity during delay periods in prefrontal cortex, especially during hard trials. Yet, details of the memoranda could not be decoded from patterns in prefrontal activity. In the patterns of activity in visual cortex, however, we found strong decoding of memorized targets, where accuracy was higher on hard trials. To potentially link these across-region effects, we hypothesized that effort, carried by persistent activity in prefrontal cortex, impacts the quality of working memory representations encoded in visual cortex. Indeed, we found that the amplitude of delay period activity in frontal cortex predicted decoded accuracy in visual cortex on a trial-wise basis. These results indicate that effort-related feedback signals sculpt population activity in visual cortex, improving mnemonic fidelity.Significance Statement A full understanding of the neural mechanisms underlying our cognitive abilities depends on understanding their interplay with factors such as cognitive effort. Here, we relied on the simple intuition that some tasks require more effort than others and success depends on how hard we try. We show how the exertion of cognitive effort - trying harder - improves the quality of working memory representations in visual cortex mediated by feedback from prefrontal cortex. Such a mechanism describes how the limited resources that support working memory are allocated and strategically controlled. These results have implications for psychiatric disorders, like schizophrenia, where motivational deficits may masquerade as cognitive dysfunction.