Motor systems must adapt to perturbations and changing conditions both within outside the body. We refer ability of a system maintain performance despite as "robustness," deploy alternative strategies that improve fitness "flexibility." Different classes pattern-generating circuits yield dynamics with differential sensitivities parameter variation. Depending on task type perturbation, high sensitivity can either facilitate or hinder robustness flexibility. Here we explore role multiple...

Abstract Objective. To understand neural circuit dynamics, it is critical to manipulate and record many individual neurons. Traditional recording methods, such as glass microelectrodes, can only control a small number of More recently, devices with high electrode density have been developed, but few them be used for intracellular or stimulation in intact nervous systems. Carbon fiber electrodes (CFEs) are 8 µ m-diameter that assembled into dense arrays (pitches ⩾ 80 m). They good...

<title>Abstract</title> Water waves help aquatic animals locate environmental stimuli. While previous studies suggest that leech mechanoreceptors have evolved to respond relevant wave frequencies, the underlying neural processing remains unclear. This work presents a simplified computational model mimics goal seeking behavior in an agent-based simulation. A simulated was tasked with finding source of artificial water stimulus. The agent's distributed mechanoreceptor array detected motion,...

Adaptive behavior is critical for animals’ survival. A multifunctional nervous system crucial to generate behaviors that respond effectively the changing environment. Multiple mechanisms behind a neural circuit have been found in vertebrate and invertebrate systems: change can occur at cellular level, synaptic level as well circuitry level. Aplysia’s feeding capable of producing different modes behavior. In Aplysia, B4/B5 are two electrically coupled multi-action neurons wide inhibitory...

Many behaviors require reliably generating sequences of motor activity while adapting the to incoming sensory information. This process has often been conceptually explained as either fully dependent on input (a chain reflex) or independent (an idealized central pattern generator, CPG), although consensus field is that most neural generators lie somewhere between these two extremes. mathematical models use limit cycles generate sequence behaviors, but other models, such a heteroclinic...

How does motor neuronal variability affect behavior? To explore this question, we quantified activity of multiple individual identified neurons mediating biting and swallowing in intact, behaving Aplysia californica by recording from the protractor muscle three nerves containing majority controlling feeding musculature. We measured components: duration as well their relative timing. At same time, behavioral efficacy: amplitude grasping movement during net inward food swallowing. observed...

Abstract As they interact with their environment and encounter challenges, animals adjust behavior on a moment-to-moment basis to maintain task fitness. This dynamic process of adaptive motor control occurs in the nervous system, but an understanding biomechanics body is essential properly interpret behavioral outcomes. To study how respond changing conditions, we used model system which functional roles identified neurons relevant are well understood can be studied intact behaving animals:...

Certain animal species use the Earth's magnetic field (i.e. magnetoreception) alongside their other sensory modalities to navigate long distances that include continents and oceans. It is hypothesized several animals geomagnetic parameters, such as intensity inclination, recognize specific locations or regions, potentially enabling migration without a pre-surveyed map. However, it unknown how information generate guidance commands, where in world this type of strategy would maximize an...

Changes caused by learning that a food is inedible in Aplysia were examined for fast and slow synaptic connections from the buccal ganglia S1 cluster of mechanoafferents to five followers, response repeated stimulus trains. Learning affected only connections. For these, unique patterns change present each follower, indicating differentially affects different branches their followers. In some there increases either excitatory or inhibitory connections, others, decreases. connectivity resulted...

Shape versus Timing: Linear Responses of a Limit Cycle with Hard Boundaries under Instantaneous and Static Perturbation

The Synthetic Nervous System (SNS) is a biologically inspired neural network (NN). Due to its capability of capturing complex mechanisms underlying computation, an SNS model candidate for building compact and interpretable NN controllers robots. Previous work on SNSs has focused applying the control legged robots design functional subnetworks (FSNs) realize dynamical systems. However, FSN approach previously relied analytical solution governing equations, which difficult designing more...

The mechanical forces experienced during movement and the time constants of muscle activation are important determinants durations behaviors, which may both be affected by size-dependent scaling. mechanics slow movements in small animals dominated elastic thus quasistatic (i.e., always near equilibrium). Muscular producing resisting should scale identically (proportional to mass⅔), leaving scaling constant play a critical role determining behavioral duration. We tested this hypothesis...

Motor systems show an overall robustness, but because they are highly nonlinear, understanding how achieve robustness is difficult. In many rhythmic systems, against perturbations involves response of both the shape and timing trajectory. This makes study even more challenging. To understand a motor system produces robust behaviors in variable environment, we consider neuromechanical model patterns feeding apparatus marine mollusk Aplysia californica (Shaw et al. J Comput Neurosci...

Abstract A software tool for synchronization of video with signals would be broad general use to behavioral neuroscientists. new program, called neurotic (NEUROscience Tool Interactive Characterization), allows users review and annotate signal data synchronized video, performs simple initial analyses including filtering spike detection, is easy use, supports a variety file formats. The program also facilitates collaborations by using portable specification loading processing retrieving files...

Dynamics of Biological Systems, the IBI Prize–winning module, brings mathematics into biology laboratory.

Abstract Studying the nervous system underlying animal motor control can shed light on how animals adapt flexibly to a changing environment. We focus neural basis of feeding in Aplysia californica . Using Synthetic Nervous System framework, we developed model circuitry that balances neurophysiological plausibility and computational complexity. The includes neurons, synapses, feedback pathways identified existing literature. organized neurons into three layers five subnetworks according their...

Abstract The coordination of complex behavior requires knowledge both neural dynamics and the mechanics periphery. feeding system Aplysia californica is an excellent model for investigating questions in soft body systems’ neuromechanics because its experimental tractability. Prior work has attempted to elucidate mechanical properties periphery by using a Hill-type muscle characterize force generation capabilities key protractor responsible moving ’s grasper anteriorly, I2 muscle. However,...

To understand how behaviors arise in animals, it is necessary to investigate both the neural circuits and biomechanics of periphery. A tractable model system for studying multifunctional control feeding apparatus marine mollusk Aplysia californica. Previous silico roboto models have investigated nervous muscular systems interact this system. However, these are still limited their ability match vivo data qualitatively quantitatively. We introduce a new neuromechanical that combines modified...