Differential cognitive effects of Ginkgo biloba after acute and chronic treatment in healthy young volunteers

Psychopharmacology (Berl). 2005 May;179(2):437-46. doi: 10.1007/s00213-005-2206-6. Epub 2005 Mar 1.


Rationale: Acute doses of Ginkgo biloba have been shown to improve attention and memory in young, healthy participants, but there has been a lack of investigation into possible effects on executive function. In addition, only one study has investigated the effects of chronic treatment in young volunteers.

Objectives: This study was conducted to compare the effects of ginkgo after acute and chronic treatment on tests of attention, memory and executive function in healthy university students.

Methods: Using a placebo-controlled double-blind design, in experiment 1, 52 students were randomly allocated to receive a single dose of ginkgo (120 mg, n=26) or placebo (n=26), and were tested 4 h later. In experiment 2, 40 students were randomly allocated to receive ginkgo (120 mg/day; n=20) or placebo (n=20) for a 6-week period and were tested at baseline and after 6 weeks of treatment. In both experiments, participants underwent tests of sustained attention, episodic and working memory, mental flexibility and planning, and completed mood rating scales.

Results: The acute dose of ginkgo significantly improved performance on the sustained-attention task and pattern-recognition memory task; however, there were no effects on working memory, planning, mental flexibility or mood. After 6 weeks of treatment, there were no significant effects of ginkgo on mood or any of the cognitive tests.

Conclusions: In line with the literature, after acute administration ginkgo improved performance in tests of attention and memory. However, there were no effects after 6 weeks, suggesting that tolerance develops to the effects in young, healthy participants.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Affect / drug effects
  • Attention / drug effects
  • Cognition / drug effects*
  • Female
  • Ginkgo biloba*
  • Humans
  • Male
  • Memory / drug effects
  • Memory, Short-Term / drug effects
  • Neuropsychological Tests
  • Pattern Recognition, Visual / drug effects
  • Plant Extracts / pharmacology
  • Psychiatric Status Rating Scales
  • Psychomotor Performance / drug effects
  • Reading
  • Space Perception / drug effects
  • Time Factors


  • Plant Extracts