267 results match your criteria: "Center for Complex Systems and Brain Sciences[Affiliation]"

Using space-filling curves and fractals to reveal spatial and temporal patterns in neuroimaging data.

J Neural Eng

January 2025

Center for Complex Systems and Brain Sciences, Universidad Nacional de San Martin Escuela de Ciencia Y Tecnologia, 25 de Mayo y Francia, San Martín, Buenos Aires, 1650, ARGENTINA.

Objective Magnetic resonance imaging (MRI), functional MRI (fMRI) and other neuroimaging techniques are routinely used in medical diagnosis, cognitive neuroscience or recently in brain decoding. They produce three- or four-dimensional scans reflecting the geometry of brain tissue or activity, which is highly correlated temporally and spatially. While there exist numerous theoretically guided methods for analyzing correlations in one-dimensional data, they often cannot be readily generalized to the multidimensional geometrically embedded setting.

View Article and Find Full Text PDF

Metastability demystified - the foundational past, the pragmatic present and the promising future.

Nat Rev Neurosci

December 2024

Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.

Healthy brain function depends on balancing stable integration between brain areas for effective coordinated functioning, with coexisting segregation that allows subsystems to express their functional specialization. Metastability, a concept from the dynamical systems literature, has been proposed as a key signature that characterizes this balance. Building on this principle, the neuroscience literature has leveraged the phenomenon of metastability to investigate various aspects of brain function in health and disease.

View Article and Find Full Text PDF

Cognitive impact and brain structural changes in long COVID patients: a cross-sectional MRI study two years post infection in a cohort from Argentina.

BMC Neurol

November 2024

Centro Universitario de Imágenes Médicas (CEUNIM), Escuela de Ciencia y Tecnología, Universidad Nacional de Gral. San Martín, Campus Miguelete, 25 de Mayo 901, San Martín, Buenos Aires, 1650, Argentina.

Objective: Long COVID is a condition characterised by persistent symptoms after a SARS-CoV-2 infection, with neurological manifestations being particularly frequent. Existing research suggests that long COVID patients not only report cognitive symptoms but also exhibit measurable cognitive impairment. Neuroimaging studies have identified structural alterations in brain regions linked to cognitive functions.

View Article and Find Full Text PDF

Mean-field solution of the neural dynamics in a Greenberg-Hastings model with excitatory and inhibitory units.

Phys Rev E

July 2024

Instituto de Física Enrique Gaviola (IFEG-CONICET), Facultad de Matemática Astronomía Física y Computación, Universidad Nacional de Córdoba, 5000 Córdoba, Argentina.

We present a mean-field solution of the dynamics of a Greenberg-Hastings neural network with both excitatory and inhibitory units. We analyze the dynamical phase transitions that appear in the stationary state as the model parameters are varied. Analytical solutions are compared with numerical simulations of the microscopic model defined on a fully connected network.

View Article and Find Full Text PDF

Minds and markets as complex systems: an emerging approach to cognitive economics.

Trends Cogn Sci

November 2024

Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL, USA; Intelligent Systems Research Centre, Ulster University, Derry ~ Londonderry, UK; Bath Institute for the Augmented Human, University of Bath, Bath, UK.

Cognitive economics is an emerging interdisciplinary field that uses the tools of cognitive science to study economic and social decision-making. Although most strains of cognitive economics share commitments to bridging levels of analysis (cognitive, behavioral, and systems) and embracing interdisciplinary approaches, we review a newer strand of cognitive economic thinking with a further commitment: conceptualizing minds and markets each as complex adaptive systems. We describe three ongoing research programs that strive toward these goals: (i) studying narratives as a cognitive and social representation used to guide decision-making; (ii) building cognitively informed agent-based models; and (iii) understanding markets as an extended mind - the Market Mind Hypothesis - analyzed using the concepts, methods, and tools of Coordination Dynamics.

View Article and Find Full Text PDF

Autism Spectrum Disorder (ASD) is defined by distinctive socio-cognitive behaviors that deviate from typical patterns. Notably, social imitation skills appear to be particularly impacted, manifesting early on in development. This paper compared the behavior and inter-brain dynamics of dyads made up of two typically developing (TD) participants with mixed dyads made up of ASD and TD participants during social imitation tasks.

View Article and Find Full Text PDF

A recent experiment probed how purposeful action emerges in early life by manipulating infants' functional connection to an object in the environment (i.e., tethering an infant's foot to a colorful mobile).

View Article and Find Full Text PDF

Interspecific dispersal constraints suppress pattern formation in metacommunities.

Philos Trans R Soc Lond B Biol Sci

July 2024

Department of Evolution, Ecology, & Organismal Biology, University of California, Riverside, CA, USA.

Decisions to disperse from a habitat stand out among organismal behaviours as pivotal drivers of ecosystem dynamics across scales. Encounters with other species are an important component of adaptive decision-making in dispersal, resulting in widespread behaviours like tracking resources or avoiding consumers in space. Despite this, metacommunity models often treat dispersal as a function of intraspecific density alone.

View Article and Find Full Text PDF

Beehive scale-free emergent dynamics.

Sci Rep

June 2024

Instituto de Ciencias Físicas (ICIFI-CONICET), Center for Complex Systems and Brain Sciences (CEMSC3), Escuela de Ciencia y Tecnología, Universidad Nacional de Gral. San Martín, Campus Miguelete, San Martín, Buenos Aires, Argentina.

It has been repeatedly reported that the collective dynamics of social insects exhibit universal emergent properties similar to other complex systems. In this note, we study a previously published data set in which the positions of thousands of honeybees in a hive are individually tracked over multiple days. The results show that the hive dynamics exhibit long-range spatial and temporal correlations in the occupancy density fluctuations, despite the characteristic short-range bees' mutual interactions.

View Article and Find Full Text PDF

The nucleus reuniens (RE) of the ventral midline thalamus is a critical node in the communication between the orbitomedial prefrontal cortex (OFC) and the hippocampus (HF). While RE has been shown to directly participate in memory-associated functions through its connections with the medial prefrontal cortex and HF, less is known regarding the role of RE in executive functioning. Here, we examined the involvement of RE and its projections to the orbital cortex (ORB) in attention and behavioral flexibility in male rats using the attentional set shifting task (AST).

View Article and Find Full Text PDF

Visual short-term memory (VSTM), the ability to store information no longer visible, is essential for human behavior. VSTM limits vary across the population and are correlated with overall cognitive ability. It has been proposed that low-memory individuals are unable to select only relevant items for storage and that these limitations are greatest when memory demands are high.

View Article and Find Full Text PDF

For people who have experienced a spinal cord injury or an amputation, the recovery of sensation and motor control could be incomplete despite noteworthy advances with invasive neural interfaces. Our objective is to explore the feasibility of a novel biohybrid robotic hand model to investigate aspects of tactile sensation and sensorimotor integration with a pre-clinical research platform. Our new biohybrid model couples an artificial hand with biological neural networks (BNN) cultured in a multichannel microelectrode array (MEA).

View Article and Find Full Text PDF

Visual fixations during processing of time-compressed audiovisual presentations.

Atten Percept Psychophys

February 2024

Department of Psychology, Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL, USA.

Time-compression is a technique that allows users to adjust the playback speed of audio recordings, but comprehension declines at higher speeds. Previous research has shown that under challenging auditory conditions people have a greater tendency to fixate regions closer to a speaker's mouth. In the current study, we investigated whether there is a similar tendency to fixate the mouth region for time-compressed stimuli.

View Article and Find Full Text PDF

Beehive scale-free emergent dynamics.

ArXiv

November 2023

Instituto de Ciencias Físicas (ICIFI-CONICET), Center for Complex Systems and Brain Sciences (CEMSC3), Escuela de Ciencia y Tecnología, Universidad Nacional de Gral. San Martín, Campus Miguelete, San Martín, Buenos Aires, Argentina.

It has been repeatedly reported that the collective dynamics of social insects exhibit universal emergent properties similar to other complex systems. In this note, we study a previously published data set in which the positions of thousands of honeybees in a hive are individually tracked over multiple days. The results show that the hive dynamics exhibit long-range spatial and temporal correlations in the occupancy density fluctuations, despite the characteristic short-range bees' mutual interactions.

View Article and Find Full Text PDF

Scale-free correlations in the dynamics of a small (N∼10000) cortical network.

Phys Rev E

September 2023

Instituto de Ciencias Físicas (ICIFI-CONICET), Center for Complex Systems and Brain Sciences (CEMSC3), Escuela de Ciencia y Tecnología, Universidad Nacional de Gral. San Martín, Campus Miguelete, 25 de Mayo y Francia, 1650 San Martín, Buenos Aires, Argentina.

The advent of novel optogenetics technology allows the recording of brain activity with a resolution never seen before. The characterization of these very large data sets offers new challenges as well as unique theory-testing opportunities. Here we discuss whether the spatial and temporal correlations of the collective activity of thousands of neurons are tangled as predicted by the theory of critical phenomena.

View Article and Find Full Text PDF

Objectives: This study aims to quantitatively evaluate whether there are muscle mass differences between male and female recreational cyclists and compare muscle quality and body composition in the pelvis region between two well-matched groups of fit and healthy male and female adults.

Methods: This cross-sectional study involved 45 female and 42 male recreational cyclists. The inclusion criteria for both groups were to have cycled more than 7000 km in the last year, have an absence of injuries and other health problems, have no contraindication to MRI, and be 30-65 years old.

View Article and Find Full Text PDF

In any environment, events transpire in temporal sequences. The general principle governing such sequences is that each instance of the event is influenced by its predecessors. It is shown here that this principle is true for a fundamental aspect of visual perception: visibility.

View Article and Find Full Text PDF

Can infant exploration and causal discovery be detected using Artificial Intelligence (AI)? A recent experiment probed how purposeful action emerges in early life by manipulating infants' functional connection to an object in the environment (., tethering one foot to a colorful mobile). Vicon motion capture data from multiple infant joints were used here to create Histograms of Joint Displacements (HJDs) to generate pose-based descriptors for 3D infant spatial trajectories.

View Article and Find Full Text PDF

Episodic memory-based decision-making requires top-down medial prefrontal cortex and hippocampal interactions. This integrated prefrontal-hippocampal memory state is thought to be organized by synchronized network oscillations and mediated by connectivity with the thalamic nucleus reuniens (RE). Whether and how the RE synchronizes prefrontal-hippocampal networks in memory, however, remains unknown.

View Article and Find Full Text PDF

Self-tuned criticality: Controlling a neuron near its bifurcation point via temporal correlations.

Phys Rev E

March 2023

Center for Complex Systems and Brain Sciences (CEMSC3), Instituto de Ciencias Físicas (ICIFI), Universidad Nacional de San Martín, Campus Miguelete, 1650 San Martín, Buenos Aires, Argentina.

Previous work showed that the collective activity of large neuronal networks can be tamed to remain near its critical point by a feedback control that maximizes the temporal correlations of the mean-field fluctuations. Since such correlations behave similarly near instabilities across nonlinear dynamical systems, it is expected that the principle should control also low-dimensional dynamical systems exhibiting continuous or discontinuous bifurcations from fixed points to limit cycles. Here we present numerical evidence that the dynamics of a single neuron can be controlled in the vicinity of its bifurcation point.

View Article and Find Full Text PDF

An Imagination - Procrastination Link? The Role of Efficacy Beliefs, Visual Imagery, and Affect in Academic Procrastination.

Psychol Rep

April 2023

Department of Psychology/Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL, USA.

Previous studies have established that there is a relationship between efficacy beliefs and procrastination. Theory and research on motivation suggest that visual imagery (the capacity to create vivid mental images) may be implicated in this relationship and in the general tendency to procrastinate. This study's aim was to build on prior work by examining the role of visual imagery, as well as roles of other specific personal and affective factors, in predicting academic procrastination.

View Article and Find Full Text PDF

Multichannel Sensorimotor Integration with a Dexterous Artificial Hand.

Res Sq

March 2023

Ocean and Mechanical Engineering Department, Florida Atlantic University, Boca Raton, Florida, FL, USA.

Background: People use their hands to perform sophisticated tasks like playing a musical instrument by integrating manifold and diverse sensations of touch with motor control strategies. In contrast, prosthetic hands lack the capacity for multichannel haptic feedback and multitasking functionality remains rudimentary. There is a dearth of research exploring the potential of upper limb absent (ULA) people to integrate multiple channels of haptic feedback into dexterous prosthetic hand control strategies.

View Article and Find Full Text PDF

Physical activity and a healthy lifestyle are crucial factors for delaying and reducing the effects of sarcopenia. Cycling has gained popularity in the last decades among midlife men. While the cardiovascular benefits of cycling and other endurance exercises have been extensively proved, the potential benefits of lifelong aerobic exercise on muscle health have not been adequately studied.

View Article and Find Full Text PDF

Identifying the midline thalamus in humans in vivo.

Brain Struct Funct

November 2023

Cognitive Neuroscience Program, Department of Psychology, Florida International University, 11200 SW 8th Street, Miami, FL, 33199, USA.

The midline thalamus is critical for flexible cognition, memory, and stress regulation in humans and its dysfunction is associated with several neurological and psychiatric disorders, including Alzheimer's disease, schizophrenia, and depression. Despite the pervasive role of the midline thalamus in cognition and disease, there is a limited understanding of its function in humans, likely due to the absence of a rigorous noninvasive neuroimaging methodology to identify its location. Here, we introduce a new method for identifying the midline thalamus in vivo using probabilistic tractography and k-means clustering with diffusion weighted imaging data.

View Article and Find Full Text PDF