Repetitive Mild Traumatic Brain Injury in a Perinatal Nicotine Exposure Mouse Model of Attention Deficit...

Area of Science:

• Neuroscience
• Behavioral Science
• Developmental Pediatrics

Background:

• Attention deficit hyperactivity disorder (ADHD) is linked to increased concussion risk.
• Participation in sports, recommended for ADHD management, carries a risk of mild traumatic brain injury (mTBI).
• The impact of untreated ADHD on outcomes of repeated mTBIs is understudied.

Purpose of the Study:

• To investigate the effects of repeated mild traumatic brain injuries (mTBIs) on behavioral outcomes in a mouse model of Attention Deficit Hyperactivity Disorder (ADHD).
• To determine if ADHD exacerbates deficits following mTBI or if mTBI worsens ADHD-related behaviors.

Main Methods:

• Utilized a perinatal nicotine exposure (PNE) mouse model, a validated preclinical model for ADHD.
• Administered repetitive closed-head mTBI or sham procedures to PNE and control mice.
• Assessed object-based attention, novel object recognition memory, spatial working memory, and depression-like behavior.

Main Results:

• Mice with ADHD (PNE group) exhibited persistent attention and working memory deficits, which were not worsened by mTBI.
• Repetitive mTBI induced a transient attention deficit in control mice but did not exacerbate ADHD-related attention deficits.
• ADHD and mTBI showed a synergistic effect on transient depression-like behavior.

Conclusions:

• ADHD may serve as a risk factor for developing transient depression following repeated mTBI.
• Repeated mTBI may increase the risk for transient attention deficits.
• These findings underscore the complex relationship between ADHD and brain injury, suggesting bidirectional influences on behavioral outcomes.