Neuroscience Seminar Series: Jacob Nordman, PhD (SIU School of Medicine)

Title: Violence is Learned: How Synaptic Plasticity in a Medial Amygdala Circuit Drives Experience-Dependent Aggression

Violent aggression poses a significant societal concern and is a prevalent symptom across various psychiatric disorders, including PTSD. In the United States alone, over one million violent crimes are reported each year, culminating in an economic burden estimated at $2.2 billion. Notably, early life stress and a background of violent abuse are strong predictors of future aggression, with statistics revealing that 38% of physically abused children are later arrested for violent crimes, and 28% face re-arrest.

Despite the grave implications of these findings, current clinical interventions for managing aggression linked to traumatic stress fall short of efficacy. Our research endeavors to bridge this gap by exploring the neurocircuitry that mediates aggression following traumatic stress. Utilizing a mouse model, we have discovered that traumatic stress prompts neuroplastic changes within a specific amygdala circuit, which in turn facilitates sustained aggressive behaviors. Remarkably, mitigating these neuroplastic alterations effectively diminishes the prolonged aggressive tendencies without influencing related fear, anxiety, or depression-like behaviors. This suggests that the identified amygdala circuit functions primarily to regulate aggression.

Further, our studies highlight the potential of NMDA receptor antagonists—key modulators of synaptic plasticity in the brain—as promising candidates for tempering traumatic stress-induced aggression. This finding opens new avenues for developing therapeutic strategies aimed at reducing anger and violence, thereby interrupting the perpetuation of violence that endangers societal well-being.

Jacob Nordman is a Mason Neuroscience PhD Alum now an Assistant Professor at Southern Illinois University School of Medicine.