Electrical Stimulation of the Midbrain to Promote Recovery from Traumatic Forebrain Injury
Abstract
This was a first attempt to improve recovery from traumatic brain injury by prolonged electrical stimulation of rat's midbrain. A fluid percussion injury was created over the right motor cortex. After 4-6 hours, we implanted a stimulating microelectrode protruding from a small, epoxy-encapsulated electronic stimulator, which was attached to the skull, and began delivering 30- microampere negative current pulses to one of two midbrain areas: the dorsal raphe or the median raphe. Stimulation was given 12 hours per day for 1 week, in 5-minute alternating on and off periods at 7-8 Hz. Comparisons were made with injured, non-stimulated rats and with uninjured rats (stimulated and non-stimulated). Behavioral testing at 6 weeks showed that learning in a hidden-platform water maze test was speeded by both dorsal and median raphe stimulation. Rearing movements in a transparent cylinder (sensorimotor performance) were normalized by the median but not the dorsal raphe. One adverse effect was seen: the dorsal but not the median raphe reduced working memory in the water maze. Initial histological inspection suggested that the dorsal raphe stimulation enlarged the hippocampus. We conclude that early median raphe stimulation with a temporary implant give permanent benefits in some types of traumatic brain injury.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2009
- Accession Number
- ADA501274
Entities
People
- Helen Bramlett
- Ian D. Hentall
Organizations
- University of Miami