The herbal remedy, available in health food shops and some pharmacies in the UK, is used in China to aid memory and fight depression.
In a trial of 330 stroke patients over six months in China, the supplement was linked with better cognitive skill scores on tests.
Experts say the evidence for ginkgo is too weak to recommend it.
Those behind the small study - published in the online journal Stroke & Vascular Neurology - admit that larger, longer and more robust trials are needed.
