Firing rate

For more than 20 years, a growing body of evidence indicates that the brain functions near a critical point, where neural activity is balanced between damping and amplification. One of the appealing benefits of criticality is its optimal information processing [1, 2]. In addition, deviations from criticality are associated with age and disease [3] but also physiological state [4]. Yet the neural mechanisms involved in maintaining and/or altering this criticality remain unclear. To investigate how cellular mechanisms can influence criticality, we analyze a model of neuronal network [5] and quan

Brains are energy-hungry and evolution has driven them to work in an energy-efficient manner. In food restriction experiments, Padamsey et al. [1] have recently observed that individual neurons trade off energy consumption and information transmission. Specifically, neurons appear to reduce energy consumption by changing their integration properties through the adaptation of membrane resistance, resting potential, and synaptic efficacies, which comes at the cost of reduced information transmission. Furthermore, they found that individual neurons assume a broad range of values of these paramete

…have regular spiking activity, slow firing rate (FR), and long action potential duration (APD). The MRN has more diverse neurochemical and electrophysiological features. In the present study, we aimed to enrich the characterization of the raphe nuclei neurons by using non-linear measures. This was done by analysing the neuronal basal firing profile in both nuclei of urethane-anesthetized rats using Ordinal Patterns (OP) Entropy, Bins Entropy, and P

Aims: Dystonia is a neurological syndrome that alters voluntary muscle control and sustained posture. The most promising targets for deep brain stimulation (DBS) are the subthalamic nucleus or Globus Pallidus internus (GPi). DBS has shown compelling therapeutic advantages in many individuals with primary generalized/segmental dystonia. However, the mechanisms of DBS still need to be clarified. In this context, we were interested in the impact of pallidal DBS on cerebellar activity. Methods: We investigated this topic using a model of primary paroxysmal dystonia (dtsz hamster, 2 months old), im

Sociability is an extremely complex behavior that requires the involvement and coordination of different brain areas. The hypothalamic neuropeptide oxytocin (OT) plays a pivotal role in regulating various aspects of social behavior and can reach and modulate many regions of the central nervous system. However, the mechanisms through which it modulates neuronal activity are still unclear, also because this peptide can exert different effects depending on the brain area and on the neuronal type. In this work, we investigated and deepened the action of OT on a specific subpopulation of interneuro

It is well-established that neurodegenerative diseases lead to structural and functional reconfigurations in neural networks. However, it is less clear how altered network dynamics contribute to increased vulnerability of specific neuronal populations to disease onset and spread. Here, we aimed to identify how ALS pathology affects the structural and functional dynamics of motor neuron networks, and the underlying biological pathways that contribute to cause such dysfunction. Multielectrode arrays (MEAs) enable longitudinal assessment of electrophysiological activity in vitro, thus facilitatin

Human induced pluripotent stem cell (hiPSC)-derived neural models have emerged as invaluable tools for studying neurological disorders, such as epilepsy, Alzheimer’s, and Parkinson’s disease.Real-time, label-free measurement of electrical activity in self-organizing in vitro cellular models provides critical insight into the complexity of their neuronal networks. High-density microelectrode arrays (HD-MEAs) enable non-invasive electrophysiological recordings from various electrogenic samples, including iPSC-derived neurons, retinal explants, brain slices, and neural organoids.In this study, we

Objectives: We aim to investigate the impact of acute stroke on delta oscillation in STN and to explore the correlation between motor disability and the altered delta oscillation in STN following stroke. Methods: 10 Sprague-Dawley rat were included in this study. They were trained in single pellet reaching task before stroke induction and motor performance was determined as baseline. STN was recorded before and 30 mins within after stroke. A photothrombotic ischemic lesion ipsilateral to the STN recording site was induced in M1. 3 days after the stroke, we evaluated motor performance using t

Neural representations of time are central to our understanding of the world around us. I review cognitive, neurophysiological and theoretical work that converges on three simple ideas. First, the time of past events is remembered via populations of neurons with a continuum of functional time constants. Second, these time constants evenly tile the log time axis. This results in a neural Weber-Fechner scale for time which can support behavioral Weber-Fechner laws and characteristic behavioral effects in memory experiments. Third, these populations appear as dual pairs---one type of population c

…exhibit a pronounced reduction in firing rate (adaptation) and even cessation of firing during sustained depolarization. We included a five state Markov model of NaV1.6

The interaction between spontaneously and externally evoked neuronal activity is fundamental for a functional brain. Increasing evidence suggests that bursts of high-power oscillations in the 15-30 Hz beta-band represent activation of resting state networks and can mask perception of external cues. Yet demonstration of the effect of beta power modulation on perception in real-time is missing, and little is known about the underlying mechanism. In this talk I will present the methods we developed to fill this gap together with our recent results. We used a closed-loop stimulus-intensity adjustm

…We showed that firing rate of image selective neurons in Medial Temporal Lobe persists through maintenance periods of working memory task. This activity was behaviorally relevant and formed attractors in its state-space. Furthermore, we showed that firing rate of those n

…suggests that the distribution of firing rates amongst neurons in a brain circuit is the key variable that is maintained around a circuit-specific set-point value in a process called firing rate homeostasis. Here, I will discuss our recent findings that implic

…progressive monotonic changes in firing rate preceding behaviorally salient points in time. Here, we investigated how timing-related activity within striatal ensembles changes with experience. We leveraged a rodent-optimized interval timing task in which mice ‘switch’ response ports after an amount of time has passed

…spike timing conditioned on the firing rate of a neuron (i.e. a Poisson process), and the second is the trial-to-trial variability of the firing rate itself. Quenching of the variability of the overall response is assumed to be a reflection of a suppression of firing rate variability. Network models have