Related Experiment Video
Updated: Jun 23, 2026
11:13
Ex Vivo Optogenetic Dissection of Fear Circuits in Brain Slices
Published on: April 5, 2016
Extinction circuits for fear and addiction overlap in prefrontal cortex
Jamie Peters1, Peter W Kalivas, Gregory J Quirk
1Department of Psychiatry, University of Puerto Rico School of Medicine, San Juan, Puerto Rico 00936. petersjl.upr@gmail.com
Learning & Memory (Cold Spring Harbor, N.Y.)
|April 22, 2009
Summary
Extinction learning suppresses conditioned responses like fear and drug seeking. The medial prefrontal cortex (mPFC) is key, with distinct pathways controlling behavior expression and suppression, offering therapeutic targets.
Area of Science:
- Neuroscience
- Behavioral Science
- Psychology
Background:
- Extinction is inhibitory learning that suppresses conditioned responses.
- Maladaptive fear and drug seeking manifest as anxiety disorders and addiction.
- The medial prefrontal cortex (mPFC) is crucial for extinction of fear and drug seeking.
Purpose of the Study:
- To investigate the role of the medial prefrontal cortex (mPFC) in the extinction of fear and drug-seeking behaviors.
- To explore the dorsal-ventral distinction within the mPFC and its projections in regulating these behaviors.
Main Methods:
- Review of recent evidence on mPFC function in inhibitory learning.
- Analysis of divergent projections from mPFC subregions (PL-mPFC and IL-mPFC) to amygdala and nucleus accumbens.
Main Results:
- A dorsal-ventral distinction exists in the mPFC: prelimbic cortex (PL-mPFC) drives expression, while infralimbic cortex (IL-mPFC) mediates suppression.
- Divergent projections to amygdala (fear) and nucleus accumbens (drug seeking) underlie this mPFC dichotomy.
- The mPFC acts as a common node in extinction circuits for both fear and drug seeking.
Conclusions:
- The mPFC's distinct subregions and projections are critical for suppressing conditioned fear and drug seeking.
- Targeting the mPFC may offer a unified therapeutic strategy for anxiety and addiction disorders by enhancing extinction memory.
Related Concept Videos
01:24Generalization, Discrimination, and Extinction
Generalization, discrimination, and extinction are key concepts in operant conditioning that influence how behaviors are learned and maintained.
Generalization occurs when a behavior reinforced in one context is performed in similar situations. For instance, a student who studies diligently for calculus and receives excellent grades might apply the same study habits to psychology and history, expecting similar results. Generalization shows how learning in one setting can influence behavior in...
Generalization occurs when a behavior reinforced in one context is performed in similar situations. For instance, a student who studies diligently for calculus and receives excellent grades might apply the same study habits to psychology and history, expecting similar results. Generalization shows how learning in one setting can influence behavior in...
01:15Drug Abuse and Addiction: Pharmacological Phenomena
Drug dependence, abuse, and addiction are complex phenomena that can precipitate various abnormal states. Physical dependence refers to a state of pharmacological adaptation to a drug. This adaptation often results in tolerance—a reduced response to the drug after repeated administrations. When the drug use is abruptly stopped, withdrawal symptoms occur due to the body's need to readjust from the pharmacologically induced imbalance. However, tolerance and withdrawal symptoms do not necessarily...
01:15Real-World Application of Classical Conditioning
Classical conditioning not only includes the initial pairing of stimuli but also extends to more complex forms, such as higher-order conditioning. Higher-order conditioning involves creating associations beyond the primary conditioned stimulus, resulting in a chain of conditioned responses.
Higher-order, or second-order, conditioning occurs when a neutral stimulus becomes associated with an already established conditioned stimulus through repeated pairings. For instance, if a dog has been...
Higher-order, or second-order, conditioning occurs when a neutral stimulus becomes associated with an already established conditioned stimulus through repeated pairings. For instance, if a dog has been...
01:15Functional Brain Systems: Limbic System
The limbic system, often called the "emotional brain," is a complex set of structures located deep within the brain. The intricate network of the limbic system supports a wide range of psychological functions, from emotional regulation to memory formation and sensory processing. This functional brain region encompasses specific parts of the diencephalon and the cerebrum, integrating the higher mental functions of the cerebral cortex with the primitive emotional responses of the deep brain...
01:05Instinctive Drift
Instinctive drift refers to the tendency of animals to revert to their innate behaviors despite repeated reinforcement. Breland and Breland demonstrated this concept in an experiment with a raccoon. The raccoon was trained to pick up two coins and place them in a container in exchange for food. Initially, the raccoon learned to associate the coins with food, making them a conditioned stimulus or a substitute for food. However, over time, the raccoon became less willing to put the coins into the...
01:14Avoidance Learning and Learned Helplessness
Avoidance learning and learned helplessness are critical concepts in understanding behavioral responses to negative stimuli.
Avoidance learning occurs when an organism learns that a specific behavior can prevent an unpleasant outcome. For example, a student who receives a bad grade may start studying harder to avoid future poor grades. This behavior persists even when the negative outcome is no longer present. Avoidance learning is powerful because it maintains behavior in the absence of the...
Avoidance learning occurs when an organism learns that a specific behavior can prevent an unpleasant outcome. For example, a student who receives a bad grade may start studying harder to avoid future poor grades. This behavior persists even when the negative outcome is no longer present. Avoidance learning is powerful because it maintains behavior in the absence of the...