Effect of lecithin on memory in normal adults.

In a double-blind, placebo-controlled, crossover study of the effect of lecithin on memory test performance, nine normal paid volunteers (age range = 22-55 years) took single oral doses of placebo and lecithin (20 g) 5 hours before cognitive testing. Lecithin raised plasma choline levels during the test session to nearly double the placebo levels, but a categorized serial learning task, a word recognition task, a paired associates learning task, and a test of retrieval by category demonstrated no significant change in memory performance. Lecithin did not selectively enhance memory for low-imagery words. Lecithin also had no effect on psychomotor speed.