Low-Intensity Blast Exposure Induces Multifaceted Long-Lasting Anxiety-Related Behaviors in Mice

Area of Science:

• Neuroscience
• Behavioral Science
• Military Medicine

Background:

• Primary blast exposure is a leading cause of mild traumatic brain injury (mTBI) in military personnel.
• mTBI can result in persistent behavioral disturbances affecting quality of life.
• Previous research using the "Missouri Blast" model indicated cognitive and affective deficits after low-intensity blast (LIB) exposure.

Purpose of the Study:

• To investigate long-term behavioral changes following LIB-induced mTBI.
• To evaluate anxiety-related behaviors and sociability in mice three months post-injury.
• To utilize multifaceted conventional and advanced behavioral paradigms for comprehensive assessment.

Main Methods:

• C57BL/6J male mice (2 months old) were exposed to a non-inertial primary LIB-induced mTBI.
• Behavioral evaluations were conducted three months post-injury.
• Tests included the open-field test (OFT), social interaction test, and the Erasmus Ladder paradigm.

Main Results:

• The open-field test (OFT) showed no significant anxiety-like changes or differences in center-zone activity between LIB-exposed mice and controls.
• While not reaching statistical significance, LIB-exposed mice initiated fewer social interactions, suggesting decreased sociability.
• The Erasmus Ladder test revealed increased instances of "escape behavior" in LIB-exposed mice, indicative of anxiety-related activity not detected by the OFT.

Conclusions:

• Low-intensity blast (LIB) exposure induces subtle, multifaceted, and long-lasting anxiety-relevant behavioral effects.
• The observed behaviors suggest a complex interplay of anxiety and sociability deficits post-mTBI.
• The "Missouri Blast" model provides a foundation for future research into the biological mechanisms underlying blast-induced behavioral changes.