Effect of Short-term Theta Frequency Stimulation of the Vagus Nerve on Cognition in Patients With Refractory Epilepsy

Effect of Short-term Theta Frequency Stimulation of the Vagus Nerve on Cognition : a Pilot Study

The purpose of this investigation is data pilot study of the effect of theta frequency stimulation of the vagus nerve on cognitive performance in patients with refractory epilepsy. We will compare the effects of no stimulation, theta frequency (5 Hz), and 'standard' beta frequency stimulation (25-30 Hz) on cognitive measures. We hypothesize that theta frequency VNS will have a positive effect on memory retention. The goal of this study to provide initial data to inform the design of a larger clinical trial to examine the efficacy of theta VNS.

Inclusion Criteria:

1. Diagnosis of Refractory Epilepsy
2. Previously implanted vagal nerve stimulator
3. Willingness and ability to undergo temporary changes to their VNS device settings

Exclusion Criteria:

1. <18 years of age
2. Adults unable to consent
3. Pregnant women
4. Prisoners
5. >20 on the Beck Depression Inventory (BDI)
6. <24 on the Montreal Cognitive Assessment (MOCA)
7. Adults with diagnosis of developmental delay, intellectual disability, or traumatic brain injury (TBI).
8. Adults with reported history of learning disability.
9. Adults unable to use a computer with their dominant hand.
10. Status Epilepticus within the past 6 months