Isoflurane Causes Anterograde but Not Retrograde Amnesia for Pavlovian Fear Conditioning

2002 ◽  
Vol 96 (5) ◽  
pp. 1223-1229 ◽  
Author(s):  
Robert C. Dutton ◽  
Anya J. Maurer ◽  
James M. Sonner ◽  
Michael S. Fanselow ◽  
Michael J. Laster ◽  
...  
Keyword(s):  
Fear Conditioning ◽  
Retrograde Amnesia ◽  
Minimum Alveolar Concentration ◽  
Conditioned Fear ◽  
Pavlovian Fear Conditioning ◽  
Conditioning Procedure ◽  
Trial Procedure ◽  
Learning Procedure ◽  
The One ◽  
Dose Dependent

Background Production of retrograde amnesia by anesthetics would indicate that these drugs can disrupt mechanisms that stabilize memory. Such disruption would allow suppression of memory of previous untoward events. The authors examined whether isoflurane provides retrograde amnesia for classic (Pavlovian) fear conditioning. Methods Rats were trained to fear tone by applying three (three-trial) or one (one-trial) tone-shock pairs while breathing various constant concentrations of isoflurane. Immediately after training, isoflurane administration was either discontinued, maintained unchanged, or rapidly increased to 1.0 minimum alveolar concentration for 1 h longer. Groups of rats were similarly trained to fear context while breathing isoflurane by applying shocks (without tones) in a distinctive environment. The next day, memory for the conditioned stimuli was determined by presenting the tone or context (without shock) and measuring the proportion of time each rat froze (appeared immobile). For each conditioning procedure, the effects of the three posttraining isoflurane treatments were compared. Results Rapid increases in posttraining isoflurane administration did not suppress conditioned fear for any of the training procedures. In contrast, isoflurane administration during conditioning dose-dependently suppressed conditioning (P < 0.05). Training to tone was more resistant to the effects of isoflurane than training to context (P < 0.05), and the three-trial learning procedure was more was more resistant than the one-trial procedure (P < 0.05). Conclusions Isoflurane provided intense dose-dependent anterograde but not retrograde amnesia for classic fear conditioning. Isoflurane appears to disrupt memory processes that occur at or within a few minutes of the conditioning procedure.

scholarly journals Slow Late Component in Conditioned Stimulus-Evoked Potentials From the Amygdala After Fear Conditioning in the Rat

2002 ◽  
Vol 9 (4) ◽  
pp. 261-272 ◽  
Author(s):  
J. M. J. Knippenberg ◽  
E. L. J. M. van Luijtelaar ◽  
J. H. R. Maes
Keyword(s):  
Evoked Potentials ◽  
Fear Conditioning ◽  
Slow Component ◽  
Pavlovian Fear Conditioning ◽  
Late Component ◽  
Conditioning Procedure ◽  
Experimental Conditions ◽  
Before And After ◽  
Male Wistar Rats ◽  
Lateral Nucleus

Male Wistar rats were subjected to a differential Pavlovian fear conditioning procedure in which one of two tones (6 or 10 kHz) was followed by an electric shock (CS+) and the other was not (CS-). Before and after fear conditioning, we recorded the evoked potentials elicited byCS+andCS-from electrodes aimed at the lateral nucleus of the amygdala. Before conditioning, a slow, negative component with peak amplitude around 150 ms was present in the evoked potentials. This component was sensitive to habituation. After fear conditioning, bothCS+andCS-elicited the same late component, albeit with a larger amplitude. This enhancement was temporary: decreasing amplitude was observed in the course of CS test presentations under extinction. Prior research revealed a comparable slow component in the amygdala of the cat under similar experimental conditions. The collective results indicate that the large late component in the amygdala is enhanced by fear conditioning, suggesting that such enhancement reflects the anticipation of a biologically significant event.

scholarly journals Medial Orbitofrontal Cortex Regulates Instrumental Conditioned Punishment, but not Pavlovian Conditioned Fear

2020 ◽  
Author(s):  
Cassandra Ma ◽  
Philip Jean-Richard-dit-Bressel ◽  
Stephanie Roughley ◽  
Bryce Vissel ◽  
Bernard W Balleine ◽  
...  
Keyword(s):  
Fear Conditioning ◽  
Orbitofrontal Cortex ◽  
Conditioned Fear ◽  
Causal Link ◽  
Pavlovian Fear Conditioning ◽  
Compulsive Disorders ◽  
Sensitivity To Punishment

Abstract Bidirectionally aberrant medial orbitofrontal cortical (mOFC) activity has been consistently linked with compulsive disorders and related behaviors. Although rodent studies have established a causal link between mOFC excitation and compulsive-like actions, no such link has been made with mOFC inhibition. Here we use excitotoxic lesions of mOFC to investigate its role in sensitivity to punishment; a core characteristic of many compulsive disorders. In our first experiment, we demonstrated that mOFC lesions prevented rats from learning to avoid a lever that was punished with a stimulus that co-terminated with footshock. Our second experiment demonstrated that retrieval of punishment learning is also somewhat mOFC-dependent, as lesions prevented the extended retrieval of punishment contingencies relative to shams. In contrast, mOFC lesions did not prevent rats from re-acquiring the ability to avoid a punished lever when it was learned prior to lesions being administered. In both experiments, Pavlovian fear conditioning to the stimulus was intact for all animals. Together, these results reveal that the mOFC regulates punishment learning and retrieval in a manner that is separate from any role in Pavlovian fear conditioning. These results imply that aberrant mOFC activity may contribute to the punishment insensitivity that is observed across multiple compulsive disorders.

scholarly journals Impairment in acquisition of conditioned fear in schizophrenia: a pooled analysis of four studies

2021 ◽  
Author(s):  
Lauri Tuominen ◽  
Liana Romaniuk ◽  
Mohammed R Milad ◽  
Donald C Goff ◽  
Jeremy Hall ◽  
...  
Keyword(s):  
Associative Learning ◽  
Fear Conditioning ◽  
Conditioned Fear ◽  
Pooled Analysis ◽  
Control Group ◽  
Pavlovian Fear Conditioning ◽  
Schizophrenia Group ◽  
Skin Conductance Responses ◽  
Sufficient Power ◽  
Prior Models

Background: Individuals with schizophrenia show impairments in associative learning. One well-studied, quantifiable form of associative learning is Pavlovian fear conditioning. However, to date, studies of fear conditioning in schizophrenia have been inconclusive, possibly because they lacked sufficient power. Methods: To address this issue, data were pooled from 4 independent fear conditioning studies that included a total of 77 individuals with schizophrenia and 74 control subjects. Skin conductance responses (SCRs) during fear conditioning to stimuli that were paired (the CS+) and not paired (CS-) with an aversive, unconditioned stimulus were measured, and the success of acquisition of differential conditioning (the magnitude of CS+ vs CS- SCRs) and responses to CS+ and CS- separately were assessed. Results: Acquisition of differential conditioned fear responses was significantly lower in individuals with schizophreania than in healthy controls (Cohen's d = 0.53). This effect was primarily related to a significantly higher response to the CS- stimulus in the schizophrenia compared to the control group. The magnitude of this response to the CS- in the schizophrenia group was correlated with the severity of delusional ideation. Other symptoms or antipsychotic dose were not associated with fear conditioning measures. Conclusions: Individuals with schizophrenia who endorse delusional beliefs are over-responsive to neutral stimuli during fear conditioning. This finding is consistent with prior models of aberrant learning in psychosis.

scholarly journals Vicarious conditioned fear acquisition and extinction in child–parent dyads

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Marie-France Marin ◽  
Alexe Bilodeau-Houle ◽  
Simon Morand-Beaulieu ◽  
Alexandra Brouillard ◽  
Ryan J. Herringa ◽  
...  
Keyword(s):  
Fear Conditioning ◽  
Conditioned Fear ◽  
Fear Learning ◽  
Actual Process ◽  
Conditioning Procedure ◽  
Learning Mechanisms ◽  
Conditioning Paradigm ◽  
Extinction Process ◽  
Skin Conductance Responses ◽  
Fear And Anxiety

Abstract The biological mechanisms involved in fear transmission within families have been scarcely investigated in humans. Here we studied (1) how children acquired conditioned fear from observing their parent, or a stranger, being exposed to a fear conditioning paradigm, and (2) the subsequent fear extinction process in these children. Eighty-three child-parent dyads were recruited. The parent was filmed while undergoing a conditioning procedure where one cue was paired with a shock (CS + Parent) and one was not (CS −). Children (8 to 12 years old) watched this video and a video of an adult stranger who underwent conditioning with a different cue reinforced (CS + Stranger). Children were then exposed to all cues (no shocks were delivered) while skin conductance responses (SCR) were recorded. Children exhibited higher SCR to the CS + Parent and CS + Stranger relative to the CS −. Physiological synchronization between the child’s SCR during observational learning and the parent’s SCR during the actual process of fear conditioning predicted higher SCR for the child to the CS + Parent. Our data suggest that children acquire fear vicariously and this can be measured physiologically. These data lay the foundation to examine observational fear learning mechanisms that might contribute to fear and anxiety disorders transmission in clinically affected families.

Strain Differences in Acquisition and Extinction of Fear Responses in Rats

1976 ◽  
Vol 38 (1) ◽  
pp. 163-187 ◽  
Author(s):  
Gudrun Sartory ◽  
Hans J. Eysenck
Keyword(s):  
Fear Conditioning ◽  
Retention Test ◽  
Conditioned Fear ◽  
Strain Differences ◽  
Pavlovian Fear Conditioning ◽  
Test Results ◽  
Fear Response ◽  
Maudsley Strains ◽  
Step Down ◽  
Different Strains

5 different strains of rats (Roman high and low avoiders, Maudsley reactive and non-reactive and random-bred animals) were subjected repeatedly to extinction trials following Pavlovian fear conditioning. The duration of the extinction trials was varied for different groups of animals. Fear was measured by latency of escape into the “safe” compartment in Exp. I and by step-down latency in Exp. II during a final fear-retention test. Results showed no differences between Roman high and low avoiders; for the Maudsley strains, however, results suggested that the higher the basal fear level the stronger is the acquired fear response and the more time is required for its extinction. Fearfulness in the animal and duration of extinction trials were jointly and severally causal in determining degree of extinction of the conditioned fear response.

The evaluation of Teucrium persicum methanolic extract and its fractions in Pavlovian Fear Conditioning

Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
H Monsef Esfahani ◽  
M Sharifzadeh ◽  
M Moattari ◽  
A Miri ◽  
E Nasireslami
Keyword(s):  
Fear Conditioning ◽  
Methanolic Extract ◽  
Pavlovian Fear Conditioning

scholarly journals Fear-induced brain activations distinguish anxious and trauma-exposed brains

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zhenfu Wen ◽  
Marie-France Marin ◽  
Jennifer Urbano Blackford ◽  
Zhe Sage Chen ◽  
Mohammed R. Milad
Keyword(s):  
Neural Network ◽  
Fear Conditioning ◽  
Psychiatric Diagnosis ◽  
Data Analytics ◽  
Conditioned Fear ◽  
Brain Regions ◽  
Brain Network ◽  
Neuroimaging Data ◽  
Task Irrelevant ◽  
Translational Models

AbstractTranslational models of fear conditioning and extinction have elucidated a core neural network involved in the learning, consolidation, and expression of conditioned fear and its extinction. Anxious or trauma-exposed brains are characterized by dysregulated neural activations within regions of this fear network. In this study, we examined how the functional MRI activations of 10 brain regions commonly activated during fear conditioning and extinction might distinguish anxious or trauma-exposed brains from controls. To achieve this, activations during four phases of a fear conditioning and extinction paradigm in 304 participants with or without a psychiatric diagnosis were studied. By training convolutional neural networks (CNNs) using task-specific brain activations, we reliably distinguished the anxious and trauma-exposed brains from controls. The performance of models decreased significantly when we trained our CNN using activations from task-irrelevant brain regions or from a brain network that is irrelevant to fear. Our results suggest that neuroimaging data analytics of task-induced brain activations within the fear network might provide novel prospects for development of brain-based psychiatric diagnosis.

scholarly journals Observational Fear Learning in Rats: Role of Trait Anxiety and Ultrasonic Vocalization

2021 ◽  
Vol 11 (4) ◽  
pp. 423
Author(s):  
Markus Fendt ◽  
Claudia Paulina Gonzalez-Guerrero ◽  
Evelyn Kahl
Keyword(s):  
Trait Anxiety ◽  
Conditioned Fear ◽  
Ultrasonic Vocalization ◽  
Fear Learning ◽  
Anxiety State ◽  
Learning Procedure ◽  
The Social ◽  
Medium Level ◽  
Male Wistar Rats

Rats can acquire fear by observing conspecifics that express fear in the presence of conditioned fear stimuli. This process is called observational fear learning and is based on the social transmission of the demonstrator rat’s emotion and the induction of an empathy-like or anxiety state in the observer. The aim of the present study was to investigate the role of trait anxiety and ultrasonic vocalization in observational fear learning. Two experiments with male Wistar rats were performed. In the first experiment, trait anxiety was assessed in a light–dark box test before the rats were submitted to the observational fear learning procedure. In the second experiment, ultrasonic vocalization was recorded throughout the whole observational fear learning procedure, and 22 kHz and 50 kHz calls were analyzed. The results of our study show that trait anxiety differently affects direct fear learning and observational fear learning. Direct fear learning was more pronounced with higher trait anxiety, while observational fear learning was the best with a medium-level of trait anxiety. There were no indications in the present study that ultrasonic vocalization, especially emission of 22 kHz calls, but also 50 kHz calls, are critical for observational fear learning.

Sign in / Sign up

Export Citation Format

Share Document