Cocaine self-administration: pharmacology and behavior

Area of Science:

• Neuroscience
• Behavioral Pharmacology
• Addiction Science

Background:

• Central nervous system (CNS) pharmacology plays a crucial role in drug self-administration.
• Understanding the neurobiological underpinnings of drug-maintained behavior is essential for addiction research.

Purpose of the Study:

• To investigate the interplay between pharmacological properties of drugs and behavioral variables in drug self-administration.
• To challenge simplistic neurobiological assumptions about drug-maintained behavior.

Main Methods:

• Examined the role of dopamine (DA) reuptake blockade and D2 receptor action in cocaine self-administration.
• Utilized drug-choice studies to assess the influence of reinforcement schedules and alternative reinforcer magnitude on drug preference.

Main Results:

• Dopamine (DA) reuptake blockade is critical for cocaine self-administration, with D2 receptor action playing a significant role.
• The schedule of reinforcement and behavioral history profoundly impact drug-maintained behavior rates and patterns.
• Drug choice dynamically interacts with both pharmacological (drug dose) and behavioral (alternative reinforcer) variables.

Conclusions:

• Increased synaptic dopamine (DA) in the CNS is insufficient to explain drug-maintained behavior.
• Drug self-administration is subject to the same behavioral laws as other behaviors, challenging the notion of it being a unique class of behavior.
• A comprehensive neurobiological model of drug abuse must integrate both pharmacological and behavioral determinants of drug reinforcing effects.