The relationship between cognitive and brain changes in posttraumatic stress disorder.

Area of Science:

• Neuroscience
• Psychiatry
• Pharmacology

Background:

• Stress impacts hippocampal structure, neurogenesis, and memory.
• Hippocampal volume reduction and memory deficits are observed in posttraumatic stress disorder (PTSD).
• Animal studies indicate serotonin reuptake inhibitors (SSRIs) and phenytoin can mitigate stress effects on the hippocampus.

Purpose of the Study:

• To investigate the effects of paroxetine and phenytoin on hippocampal volume and memory in PTSD patients.
• To assess the potential of medications to counteract stress-related brain changes in PTSD.

Main Methods:

• Two studies were conducted: one involving a year of paroxetine treatment, the other involving phenytoin treatment.
• Magnetic resonance imaging (MRI) was used to measure hippocampal volume.
• Neuropsychological testing assessed memory function.
• Positron emission tomography (PET) was used for functional imaging.

Main Results:

• Paroxetine treatment increased hippocampal volume by 5% and memory function by 35%.
• Phenytoin treatment increased right hippocampal and whole brain volume by 6% but did not significantly improve memory.
• Phenytoin was efficacious for PTSD symptoms.

Conclusions:

• Medications, including paroxetine and phenytoin, show potential in counteracting stress-induced structural changes in the hippocampus in PTSD.
• Paroxetine may improve both hippocampal volume and memory function.
• Phenytoin may be effective for PTSD symptoms and brain volume restoration, though not memory enhancement.