Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study

The effects of an extract from saffron (Crocus sativus L.) on visual short-term memory (STM) were examined in 20 volunteers. The extract was obtained from saffron petals using 100% ethylic alcohol, concentrated by vacuum evaporation, dried, and encapsulated (30 mg per capsula). Ten participants received the extract each day for three weeks, while other 10 subjects received encapsulated placebo. Then, the contrast sensitivity of a subject was estimated; sinusoidal grating patches with different contrast levels (0 – 100%) were used (experiment 1). In experiment 2, the retention of STM was assessed in two-force choice tests, using a delayed match to sample paradigm. In experiment 3, the n-back memory test with different interstimulus intervals (up to 14 sec) was used. It was found that subjects after medication with the saffron extract demonstrated better correct memorizing of the preceding visual stimuli (from two to five). At the same time, extract medication somewhat improved retention of visual STM, but only for several intermediate interstimulus intervals, and the effect was not very remarkable. Our findings emphasize the expedience to research the effects of physiologically active dietary constituents in humans.

This is a preview of subscription content, log in to check access.


  1. 1.

    J. Xu, V. D. Calhoun, G. D. Pearlson, and M. N. Potenza, “Opposite modulation of brain functional networks implicated at low vs. high demand of attention and working memory,” PLoS One, 31, No. 9 (1) (2014).

  2. 2.

    A. K. Barbey, M. Koenigs, and J. Grafman, “Orbitofrontal contribution to human working memory,” Cerebr. Cortex, 21, 789-795 (2011).

    Article  Google Scholar 

  3. 3.

    R. Sala-Llonch, C. Pena-Gomez, E. M. Arenaza-Urquijo, et al., “Brain connectivity during resting state and subsequent working memory task predicts behavioural performance,” Cortex, 48, 1187-1196 (2012).

    PubMed  Article  Google Scholar 

  4. 4.

    J. R. Jonides, D. E. Lewis, C. A. Nee, et al., “The mind and brain of short-term memory,” Annu. Rev. Psychol., 59, 193-224 (2008).

    PubMed Central  PubMed  Article  Google Scholar 

  5. 5.

    Y. Yang and N. Calakos, “Presynaptic long-term plasticity,” Front. Synapt. Neurosci., 17, No. 5, 8 (2013).

    Google Scholar 

  6. 6.

    K. Oberauer and R. A. Kliegl, “Formal model of capacity limits in working memory,” J. Mem. Lang., 55, No. 4, 601-626 (2006).

    Article  Google Scholar 

  7. 7.

    C. Berr, F. Portet, I. Carriere, et al., “Olive oil and cognition: results from the three-city study,” Dement. Geriat. Cogn. Disord., 28, No. 4, 357-364 (2009).

    CAS  Article  Google Scholar 

  8. 8.

    A. Nilsson, J. Tovar, M. Johansson, et al., “A diet based on multiple functional concepts improves cognitive performance in healthy subjects,” Nutr. Metab., 15, No. 10 (1), 49 (2013).

    Article  Google Scholar 

  9. 9.

    L. Deng, Z. N. Wu, and P. Z. Han, “Effects of different levels of food restriction on passive-avoidance memory and the expression of synapsin I in young mice,” Int. J. Neurosci., 119, No. 2, 291-304 (2009).

    CAS  PubMed  Article  Google Scholar 

  10. 10.

    T. Hashimoto and S. Watanabe, “Chronic food restriction enhances memory in mice – analysis with matched drive levels,” NeuroReport, 16, No. 10, 1129-1133 (2005).

    PubMed  Article  Google Scholar 

  11. 11.

    I. G. Newton, M. E. Forbes, C. Legault, et al., “Caloric restriction does not reverse aging-related changes in hippocampal BDNF,” Neurobiol. Aging, 26, No. 5, 683-688 (2005).

    CAS  PubMed  Article  Google Scholar 

  12. 12.

    M. C. Roberge, J. Hotte-Bernard, C. Messier, and H. Plamondon, “Food restriction attenuates ischemiainduced spatial learning and memory deficits despite extensive CA1 ischemic injury,” Behav. Brain Res., 187, No. 1, 123-132 (2008).

    CAS  PubMed  Article  Google Scholar 

  13. 13.

    S. Akhondzadeh, N. A. Tahmacebi-Pour, H. Noorbala, et al., “Crocus sativus L. in the treatment of mild to moderate depression: a double-blind, randomized and placebo-controlled trial,” Phytother. Res., 19, No. 2, 148-151 (2005).

    PubMed  Article  Google Scholar 

  14. 14.

    S. Kianbakht and A. Ghazavi, “Evaluation of immunological and hematological effects of saffron in men,” Ethnopharmacologia, 36, 78 (2005).

    Google Scholar 

  15. 15.

    M. Liakopoulou-Kyriakides and D. A. Kyriakidis, “Croscus sativus – biological active constitutents,” Stud. Nat. Prod. Chem., 26, 293-312 (2002).

    CAS  Article  Google Scholar 

  16. 16.

    D. H. Brainard, “The psychophysics toolbox,” Spat. Vis., 10, No. 4, 433-436.

  17. 17.

    M. Kleiner, D. Brainard, A. Pelli, et al., “What’s new in Psychtoolbox-3,” Perception, 36, (2007).

  18. 18.

    P. Harnett, D. McCarthy, and M. Davison, “Delayed signal detection, differential reinforcement and short term memory in the pigeon,” J. Exp. Anal. Behav., 42, 87-111 (1984).

    CAS  PubMed Central  PubMed  Article  Google Scholar 

  19. 19.

    D. McCarthy and P. Voss, “Delayed matching to sample performance: effects of relative reinforce frequency and of signal adverse unsigned reinforces magnitudes,” J. Exp. Anal. Behav., 63, 33-51 (1995).

    CAS  PubMed Central  PubMed  Article  Google Scholar 

  20. 20.

    W. K. Kirchner, “Age differences in short-term retention of rapidly changing information,” J. Exp. Psychol., 55, 352-358 (1958).

    CAS  PubMed  Article  Google Scholar 

  21. 21.

    M. S. Gazzaniga, “Cognitive neuroscience,” Concise Introd., 2 (2010).

  22. 22.

    F. J. Massey, “The Kolmogorov-Smirnov test for goodness of fit,” J. Am. Stat. Assoc., 46, No. 253, 68-78 (1951).

    Article  Google Scholar 

Download references

Author information



Corresponding author

Correspondence to G. H. Meftahi.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Ghodrat, M., Sahraei, H., Razjouyan, J. et al. Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study. Neurophysiology 46, 247–253 (2014). https://doi.org/10.1007/s11062-014-9436-3

Download citation


  • saffron
  • short-term memory
  • visual memory
  • contrast sensitivity test
  • delayed match to a sample paradigm
  • n-back memory test