The neural splicer is a device used to combat psychic abilities in their effect on brainwaves.
History[]
When a horde of psychic starfish attempted to invade Earth-26, Harrison Nash Wells used the neural splicer to prevent it.
Sometime later, after all of the multiverse's Harrison Wells were crammed into his brain, Team Flash attempted to use it to get all but Nash out, on Nash's apparent instruction. However, it turned out to be a trick by Eobard Thawne, causing them to be momentarily knocked out so that Thawne could escape.[1]