Prefrontal Cortical Opioids and Dysregulated Motivation: A Network Hypothesis

Area of Science:

• Neuroscience
• Psychiatry
• Behavioral Science

Background:

• Loss of inhibitory control over appetitive behaviors is a hallmark of psychiatric disorders like addiction and eating disorders.
• The prefrontal cortex (PFC) plays a critical role in regulating motivated behaviors and executive functions.

Purpose of the Study:

• To discuss novel actions of μ-opioid peptides within the PFC contributing to inhibitory control deficits.
• To explore how excessive μ-opioid receptor (μ-OR) signaling in the PFC perturbs neural networks and leads to disorganized appetitive responses.

Main Methods:

• Review and synthesis of existing evidence from human neuroimaging and animal studies.
• Discussion of the functional roles of PFC output pathways, including PFC→hypothalamus and PFC→striatum projections.

Main Results:

• Excessive intra-PFC μ-opioid receptor (μ-OR) signaling alters the PFC's response to excitatory input.
• This leads to aberrant recruitment of PFC output pathways, disrupting the balance between appetitive drive and limitation.
• Network perturbation results in disorganized, impulsive appetitive behaviors.

Conclusions:

• Dysregulated μ-opioid signaling in the PFC is a potential mechanism underlying inhibitory control deficits in psychiatric disorders.
• Combinatorial drug treatments targeting μ-ORs and specific PFC subcortical targets warrant exploration for therapeutic interventions.