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Nature Communications Mar 2019The ventral tegmental area (VTA) is a heterogeneous midbrain structure, containing neurons and astrocytes, that coordinates behaviors by integrating activity from...
The ventral tegmental area (VTA) is a heterogeneous midbrain structure, containing neurons and astrocytes, that coordinates behaviors by integrating activity from numerous afferents. Within neuron-astrocyte networks, astrocytes control signals from distinct afferents in a circuit-specific manner, but whether this capacity scales up to drive motivated behavior has been undetermined. Using genetic and optical dissection strategies we report that VTA astrocytes tune glutamatergic signaling selectively on local inhibitory neurons to drive a functional circuit for learned avoidance. In this circuit, astrocytes facilitate excitation of VTA GABA neurons to increase inhibition of dopamine neurons, eliciting real-time and learned avoidance behavior that is sufficient to impede expression of preference for reward. Loss of one glutamate transporter (GLT-1) from VTA astrocytes selectively blocks these avoidance behaviors and spares preference for reward. Thus, VTA astrocytes selectively regulate excitation of local GABA neurons to drive a distinct avoidance circuit that opposes approach behavior.
Topics: Amino Acid Transport System X-AG; Animals; Astrocytes; Avoidance Learning; Choice Behavior; Dopaminergic Neurons; Female; GABAergic Neurons; Glutamic Acid; Male; Mice, Inbred C57BL; Models, Biological; Neural Inhibition; Ventral Tegmental Area
PubMed: 30926783
DOI: 10.1038/s41467-019-09131-y -
International Journal of Environmental... Mar 2021This study explored the relationships between media exposure, cancer beliefs, and cancer information-seeking or information-avoidance behaviors. Based on the planned...
This study explored the relationships between media exposure, cancer beliefs, and cancer information-seeking or information-avoidance behaviors. Based on the planned risk information-seeking model and its extended framework, two predictive models were constructed: one for cancer information seeking and the other for cancer information avoidance. A structural equation modeling strategy was applied to survey data from China HINTS 2017 ( = 3090) to compare the impact of traditional mass media and social media exposure to cancer-related information on cancer information-seeking and information-avoidance behaviors. The study findings suggest that health-related information exposure through different media channels may generate distinctive information-seeking or information-avoidance behaviors based on various cancer beliefs. Additionally, the findings indicate that social media exposure to health-related and cancer curability beliefs does not lead to cancer information avoidance; both mass media and social media exposure encourage people to seek cancer-related information. Cancer fatalism is positively associated with cancer information-seeking and avoiding intentions, suggesting that negative cancer beliefs predict seemingly contradictory yet psychologically coherent information intentions and behaviors.
Topics: Avoidance Learning; China; Humans; Information Seeking Behavior; Mass Media; Neoplasms; Surveys and Questionnaires
PubMed: 33803594
DOI: 10.3390/ijerph18063130 -
The Journal of Pain 2020Avoidance is considered key in the development of chronic pain. However, little is known about how avoidance behavior subsequently affects pain-related fear and pain. We...
Avoidance is considered key in the development of chronic pain. However, little is known about how avoidance behavior subsequently affects pain-related fear and pain. We investigated this using a robotic arm reaching avoidance task. In a between-subjects design both Experimental Group (n = 30) and Yoked Control Group (n = 30) participants perform either of 3 movement trajectories (T1-T3) to reach a target location. During acquisition, only participants of the Experimental Group could partially or fully avoid a painful electrocutaneous stimulus by choosing the intermediate trajectory (T2; 50% reinforcement) or the longest trajectory (T3; 0% reinforcement) versus the shortest trajectory (T1: 100% reinforcement). After acquisition, contingencies changed (all trajectories 50% reinforced), and the acquired avoidance behavior no longer effectively prevented pain from occurring. The Yoked Control Group received the same reinforcement schedule as the Experimental Group irrespective of their behavior. When avoidance behavior became ineffective for the Experimental Group, pain-related fear increased for the previously safe(r) trajectories (T2 and T3) and remained the same for T1, whereas pain threshold and tolerance declined. For the Yoked Group, pain-related fear increased for all trajectories. The Experimental Group persisted in emitting avoidance behavior following the contingency change, albeit at a lower frequency than during acquisition. PERSPECTIVE: Results indicate participants become more afraid of and sensitive to pain, when previously acquired avoidance is no longer effective. Also, participants continue to show avoidance behavior despite it being not adaptive anymore. These findings suggest that ineffective avoidance may play role in the maintenance and development of chronic pain.
Topics: Adolescent; Adult; Arm; Avoidance Learning; Electric Stimulation; Fear; Female; Humans; Male; Middle Aged; Motor Activity; Nociceptive Pain; Pain Perception; Pain Threshold; Touch Perception; Young Adult
PubMed: 31541718
DOI: 10.1016/j.jpain.2019.09.002 -
Journal of Biological Physics Mar 2020In any ecosystem, chaotic situations may arise from equilibrium state for different reasons. To overcome these chaotic situations, sometimes the system itself exhibits...
In any ecosystem, chaotic situations may arise from equilibrium state for different reasons. To overcome these chaotic situations, sometimes the system itself exhibits some mechanisms of self-adaptability. In this paper, we explore an eco-epidemiological model consisting of three aquatic groups: phytoplankton, zooplankton, and marine free viruses. We assume that the phytoplankton population is infected by external free viruses and zooplankton get affected on consumption of infected phytoplankton; also, the infected phytoplankton do not compete for resources with the susceptible one. In addition, we model a mechanism by which zooplankton recognize and avoid infected phytoplankton, at least when susceptible phytoplankton are present. The zooplankton extinction chance increases on increasing the force of infection or decreasing the intensity of avoidance. Further, when the viral infection triggers chaotic dynamics, high zooplankton avoidance intensity can stabilize again the system. Interestingly, for high avoidance intensity, nutrient enrichment has a destabilizing effect on the system dynamics, which is in line with the paradox of enrichment. Global sensitivity analysis helps to identify the most significant parameters that reduce the infected phytoplankton in the system. Finally, we compare the dynamics of the system by allowing the infected phytoplankton also to share resources with the susceptible phytoplankton. A gradual increase of the virus replication factor turns the system dynamics from chaos to doubling state to limit cycle to stable state and the system finally settles down to the zooplankton-free equilibrium point. Moreover, on increasing the intensity of avoidance, the system shows a transcritical bifurcation from the zooplankton-free equilibrium to the coexistence steady state and remains stable thereafter.
Topics: Animals; Avoidance Learning; Models, Biological; Phytoplankton; Zooplankton
PubMed: 32180076
DOI: 10.1007/s10867-020-09538-5 -
Cell Reports Oct 2023Animals rapidly acquire surrounding information to perform the appropriate behavior. Although social learning is more efficient and accessible than self-learning for...
Animals rapidly acquire surrounding information to perform the appropriate behavior. Although social learning is more efficient and accessible than self-learning for animals, the detailed regulatory mechanism of social learning remains unknown, mainly because of the complicated information transfer between animals, especially for aversive conditioning information transmission. The current study revealed that, during social learning, the neural circuit in observer flies used to process acquired aversive conditioning information from demonstrator flies differs from the circuit used for self-learned classic aversive conditioning. This aversive information transfer is species dependent. Solitary flies cannot learn this information through social learning, suggesting that this ability is not an innate behavior. Neurons used to process and execute avoidance behavior to escape from electrically shocked flies are all in the same brain region, indicating that the fly brain has a common center for integrating external stimuli with internal states to generate flight behavior.
Topics: Animals; Drosophila; Drosophila melanogaster; Conditioning, Psychological; Avoidance Learning; Neurons
PubMed: 37782557
DOI: 10.1016/j.celrep.2023.113207 -
Behaviour Research and Therapy Mar 2020Fear motivates different types of defensive behaviors. These behaviors are, however, not mere byproducts of fear. In this review, we highlight a bi-directional... (Review)
Review
Fear motivates different types of defensive behaviors. These behaviors are, however, not mere byproducts of fear. In this review, we highlight a bi-directional relationship between conditioned fear and instrumental defensive behavior in humans. We discuss mechanisms involved in the link from fear to goal-directed avoidance (e.g., relief, generalization), that may become habitual. These defensive behaviors may in turn reduce, preserve, or amplify fear responding (e.g., protection-from-extinction, behavior-as-information). Multiple factors moderate the bi-directional relationship. Evidence for amplifying and dampening effects of inter-individual differences (e.g., trait anxiety, distress tolerance), intra-individual states (e.g., stress), and external factors (e.g., incentives for competing behavior) on goal-directed and/or habitual defensive behavior is reviewed. However, the exact mechanisms by which these factors moderate the bi-directional relationship are still largely unknown (e.g., modulating avoidance directly vs. indirectly via conditioned fear). Finally, we discuss major implications: First, understanding factors moderating the bi-directional relationship provides insights into risk and resilience factors for anxious psychopathology. Second, specific experimental models and clinical interventions can be mapped onto distinct defensive behaviors (e.g., goal-directed vs. habitual avoidance). More precise matching will help to develop nuanced models and interventions to reduce pathological behaviors and individualize treatments.
Topics: Anxiety; Avoidance Learning; Conditioning, Psychological; Extinction, Psychological; Fear; Generalization, Psychological; Humans
PubMed: 31981801
DOI: 10.1016/j.brat.2020.103550 -
Zoological Research May 2020Adult male tree shrews vigorously defend against intruding male conspecifics. However, the characteristics of social behavior have not been entirely explored in these...
Adult male tree shrews vigorously defend against intruding male conspecifics. However, the characteristics of social behavior have not been entirely explored in these males. In this study, male wild-type tree shrews ( ) and C57BL/6J mice were first allowed to familiarize themselves with an open-field apparatus. The tree shrews exhibited a short duration of movement (moving) in the novel environment, whereas the mice exhibited a long duration of movement. In the 30 min social preference-avoidance test, target animals significantly decreased the time spent by the experimental tree shrews in the social interaction (SI) zone, whereas experimental male mice exhibited the opposite. In addition, experimental tree shrews displayed a significantly longer latency to enter the SI zone in the second 15 min session (target-present) than in the first 15 min session (target-absent), which was different from that found in mice. Distinct behavioral patterns in response to a conspecific male were also observed in male tree shrews and mice in the first, second, and third 5 min periods. Thus, social behaviors in tree shrews and mice appeared to be time dependent. In summary, our study provides results of a modified social preference-avoidance test designed for the assessment of social behavior in tree shrews. Our findings demonstrate the existence of social avoidance behavior in male tree shrews and prosocial behavior in male mice toward unfamiliar conspecifics. The tree shrew may be a new animal model, which differs from mice, for the study of social avoidance and prosocial behaviors.
Topics: Animals; Avoidance Learning; Behavior, Animal; Male; Mice; Mice, Inbred C57BL; Social Behavior; Tupaiidae
PubMed: 32212430
DOI: 10.24272/j.issn.2095-8137.2020.034 -
Cell Reports May 2017Although optimizing decisions between drives to avoid pain and to obtain reward are critical for survival, understanding the neuronal circuit activity that regulates...
Although optimizing decisions between drives to avoid pain and to obtain reward are critical for survival, understanding the neuronal circuit activity that regulates choice during approach-avoidance conflicts is limited. Here, we recorded neuronal activity in the infralimbic (IL) cortex and nucleus accumbens (NAc) during an approach-avoidance task. In this task, disruption of approach by a pain-predictive cue (PPC-avoidance) is extinguished by experience and reinstated in a model of chronic pain. In the IL-NAc circuit, the activity of distinct subpopulations of neurons predicts the extent of PPC-avoidance observed. Furthermore, chemogenetic and optogenetic manipulations establish that IL-NAc circuitry regulates PPC-avoidance behavior. Our results indicate that IL-NAc circuitry is engaged during approach-avoidance conflicts, and modifications of this circuit by experience and chronic pain determine whether approach or avoidance occurs.
Topics: Animals; Avoidance Learning; Behavior, Animal; Cerebral Cortex; Chronic Pain; Cues; Nucleus Accumbens; Reward
PubMed: 28538173
DOI: 10.1016/j.celrep.2017.04.073 -
Neuron Nov 2019Long-range synchronization of neural oscillations correlates with distinct behaviors, yet its causal role remains unproven. In mice, tests of avoidance behavior evoke...
Long-range synchronization of neural oscillations correlates with distinct behaviors, yet its causal role remains unproven. In mice, tests of avoidance behavior evoke increases in theta-frequency (∼8 Hz) oscillatory synchrony between the ventral hippocampus (vHPC) and medial prefrontal cortex (mPFC). To test the causal role of this synchrony, we dynamically modulated vHPC-mPFC terminal activity using optogenetic stimulation. Oscillatory stimulation at 8 Hz maximally increased avoidance behavior compared to 2, 4, and 20 Hz. Moreover, avoidance behavior was selectively increased when 8-Hz stimulation was delivered in an oscillatory, but not pulsatile, manner. Furthermore, 8-Hz oscillatory stimulation enhanced vHPC-mPFC neurotransmission and entrained neural activity in the vHPC-mPFC network, resulting in increased synchrony between vHPC theta activity and mPFC spiking. These data suggest a privileged role for vHPC-mPFC theta-frequency communication in generating avoidance behavior and provide direct evidence that synchronized oscillations play a role in facilitating neural transmission and behavior.
Topics: Animals; Avoidance Learning; Electrophysiological Phenomena; Hippocampus; Maze Learning; Mice; Optogenetics; Prefrontal Cortex; Synaptic Transmission; Theta Rhythm
PubMed: 31521441
DOI: 10.1016/j.neuron.2019.08.006 -
Reviews in the Neurosciences 2011This review provides an overview of the assays that are used for measuring escape and avoidance behavior in zebrafish, with a specific focus on zebrafish larvae during...
This review provides an overview of the assays that are used for measuring escape and avoidance behavior in zebrafish, with a specific focus on zebrafish larvae during the first week of development. Zebrafish larvae display a startle response when exposed to tactile, acoustic, or visual stimuli and will avoid dark areas, moving objects, conspecifics, and open spaces. Emotional states such as fear and anxiety might be induced when larvae are exposed to stimuli that they would normally escape from or avoid. Although these emotional states probably differ between species and change during development, much can be learned about human fear and anxiety using zebrafish as a model system. The molecular mechanisms of fear and anxiety are highly conserved in vertebrates and are present during early zebrafish development. Larvae during the first week of development display elevated cortisol levels in response to stress and are sensitive to the same anxiolytics that are used for the management of anxiety in humans. Zebrafish larvae are well suited for high-throughput analyses of behavior, and automated systems have been developed for imaging and analyzing the behavior of zebrafish larvae in multiwell plates. These high-throughput analyses will not only provide a wealth of information on the genes and environmental factors that influence escape and avoidance behaviors and the emotional states that might accompany them but will also facilitate the discovery of novel pharmaceuticals that could be used in the management of anxiety disorders in humans.
Topics: Adaptation, Physiological; Animals; Anxiety; Avoidance Learning; Behavior, Animal; Disease Models, Animal; Environment; Escape Reaction; Heart Rate; Humans; Larva; Zebrafish
PubMed: 21572576
DOI: 10.1515/RNS.2011.008