[Effect of diazepam on visual potentials evoked by reversible checkerboard pattern]

Area of Science:

• Neuroscience
• Clinical Electrophysiology
• Pharmacology

Background:

• Visual evoked potentials (VEPs) are crucial for assessing visual pathway function.
• Diazepam (Valium) is a commonly used anxiolytic with potential effects on neural conduction.

Purpose of the Study:

• To investigate the effects of intravenous diazepam on VEPs in healthy individuals and patients with multiple sclerosis and photosensitive epilepsy.
• To compare diazepam's impact on VEP parameters across different subject groups.

Main Methods:

• Administered 10 mg of intravenous diazepam to 12 healthy subjects, 5 patients with probable multiple sclerosis, and 3 patients with photosensitive epilepsy.
• Recorded VEPs using a reversible checkerboard pattern before and after diazepam injection.
• Analyzed changes in VEP amplitude and Pmax latency.

Main Results:

• A significant decrease in VEP amplitude was observed in 75% of subjects, typically within 30 seconds to 4 minutes post-injection.
• Pmax latency prolongation occurred less frequently (65%) and was generally of low grade.
• Synchronization and late multiphasic components appeared in nearly half of the cases.
• No significant differences in diazepam's effects on VEP latency and amplitude were found between healthy subjects and patients.

Conclusions:

• Diazepam administration primarily attenuates VEP amplitude, suggesting an effect on visual pathway excitability.
• The observed changes in VEPs were consistent across healthy individuals and patients with multiple sclerosis or photosensitive epilepsy.
• Further research is warranted to elucidate the precise mechanisms of diazepam's action on visual pathway conduction.