Related Experiment Videos
State-dependent fear extinction with two benzodiazepine tranquilizers.
M E Bouton1, F A Kenney, C Rosengard
1Department of Psychology, University of Vermont, Burlington 05405.
Behavioral Neuroscience
|February 1, 1990
Summary
Benzodiazepines like chlordiazepoxide interfere with fear extinction, preventing its transfer to the undrugged state. This effect persists even with repeated drug exposure and tolerance development.
Area of Science:
- Neuroscience
- Behavioral Pharmacology
Background:
- Fear conditioning and extinction are crucial for understanding anxiety disorders.
- Benzodiazepines are commonly used anxiolytics, but their effects on fear memory processes require further investigation.
Purpose of the Study:
- To investigate if fear extinction learned under benzodiazepine influence transfers to the non-drug state.
- To determine the dose-dependency and specificity of benzodiazepine interference with fear extinction.
Main Methods:
- Rats were conditioned to fear a chamber using footshock.
- Fear extinction was conducted under placebo or benzodiazepine (chlordiazepoxide, diazepam) conditions.
- Freezing behavior was measured as an index of fear during undrugged tests.
Main Results:
- Both chlordiazepoxide and diazepam dose-dependently interfered with fear extinction, leading to increased freezing in the undrugged state.
- This interference was specific to the combination of benzodiazepines and extinction, not affecting fear elimination itself.
- Repeated drug exposure and tolerance did not diminish the interference effect.
- Evidence suggests benzodiazepines may signal or retrieve extinction rather than disrupt learning or consolidation.
Conclusions:
- Fear extinction acquired under benzodiazepine influence does not readily transfer to the undrugged state.
- Benzodiazepine-induced interference with extinction is context-specific and may involve cue-related mechanisms.
- These findings have implications for understanding the long-term efficacy of anxiolytic treatments.