Scientific Research
Founded In Science, Embracing Tradition
At Dilston Physic Garden, our roots are deeply embedded in scientific research. Our mission is to educate and inspire, bridging the gap between the wisdom of traditional plant medicine and the rigor of modern mainstream medicine. While we honour and incorporate alternative approaches, it is science that forms the foundation of our teachings and guides our, and the medical profession’s, exploration of plant medicine.
Our educational programs are designed to empower individuals with evidence-based knowledge, ensuring that every step taken in the garden is one supported by research. We believe that by merging the time-tested practices of the past with the discoveries of today, we can offer a holistic understanding of plant medicine—one that is both respected by tradition and validated by science.
Mind Research
Studies to improve the Mind
Our research focuses on plant medicines traditionally used to support mental well-being, with a particular emphasis on plants that benefit the mind and brain improving memory and sleep. Given that so much of our overall well-being is tied to an optimal mental state, our studies prioritise these areas.
If you’re interested in funding, organising or participating in a study, feel free to reach out and get involved. And don’t forget to check out our What’s On and Resources pages for the latest workshops and for information on ways to make mind-improving medicinal plants part of your daily routine.
Memory
Tincture Studies
Our Research and Trials on Memory
Based on our previous research, our first pilot trial focused on memory enhancement by testing a combination of three European plant medicines on word recall in healthy individuals. Remarkably in line with the traditional use of these plants, results showed that participants, aged 63 years and under, who took the memory tincture improved their ability to recall words correctly by over 50%, compared to those in the same age group who did not take the tincture. This study was published in Phytomedicine: A randomised double-blind placebo-controlled pilot trial of a combined extract of sage, rosemary and melissa, traditional herbal medicines, on the enhancement of memory in normal healthy subjects, including influence of age.
We are eagerly awaiting results from our next memory tincture trial, testing the same plant medicine at a higher medicinal dose and for a longer duration, in participants from West and South-East Northumberland. This study was devised by scientists at Dilston Physic Garden with the support of NIMH medical herbalists, The Royal Botanic Gardens, Kew & Make My Day Better Charity, the Ridley Family Charity and COGPro analysis.
Scroll down to see other memory enhancing plant medicine studies we have led or were involved with.
Tea Study 2025
Participate in Our Latest Research Study
Can tea boost your memory? Join our natural Memory Tea Study in Northumberland. Scientists at Dilston Physic Garden are offering an exciting opportunity in 2025 to participate in a study investigating the effects of our science-based Memory Tea on memory.
Do you feel your memory isn’t as sharp as it used to be? Are you concerned about the rising cases of dementia? Would you consider the possibility that medicinal plants could help, given that humans have used medicinal plants to support and enhance memory in the past, and that many modern drugs, like aspirin, originate from plants?
Dream Club
Self Assessed Sleep & Dream Pilot Study
‘Dilston Dream Club’ undertakes studies to explore and enjoy plants that enhance conscious experiences, sleep and dreaming. This pilot study tested the effects of plant tinctures on sleep and dreaming (2019-2020).
Participants took plant tinctures, without knowing the plant identity, and compared them to a placebo. While the study revealed interesting trends, several challenges impacted the results: participant compliance was low, the procedure was complex, and the alcohol in the tinctures may have influenced outcomes.
Key Findings Compared to Placebo. Catnip increased the number of dreams and reduced neutral dreams. Hemp improved sleep quality, reduced jumbled dreams, and increased long dreams. Mugwort enhanced sleep quality, increased the number of dreams, and led to more short-duration dreams. Passionflower Improved sleep quality, increased the number of dreams, and promoted long dreams. Wild Asparagus increased the number of dreams and reduced jumbled dreams. Wild Lettuce promoted long dreams.
These trends did not reach statistical significance, largely due to the small number of participants who completed the study (17 out of 28). The high dropout rate (11 out of 28) was likely due to the complexity of the procedure, which required each participant to take seven tinctures over five days, complete a 25-question feedback form, and commit to a minimum of three months. Additionally, the placebo (alcohol alone) was found to reduce both the quality and number of dreams, further complicating the results.
Enhancing Mind
Mild Psychedelic Experience Pilot Study
Dream Club also conducted a preliminary survey, where six volunteers tested tinctures from a selection of 20 plants, all of which have a historical and contemporary reputation for inducing altered states of consciousness. Participants were unaware of the plant identities. Altered states were reported with some plants, though responses varied across participants.
Positive Experiences Reported: Passionflower stimulated imagination and a sense of connectivity. Skullcap sharpened perception. Hop induced mildly euphoric, dream-like, ‘spaced out’ states. Lemon Balm promoted mild euphoria. Mugwort increased dream intensity. Wild Lettuce heightened sensory perceptions. Blue Lotus altered self-perception. Vervain and Bay induced visions.
We are open to discussions with anyone interested in further exploring the effects of safe plants that enhance conscious states, such as dreaming, creativity, perception, mood, and spirituality. Based on our Dream Club results so far, future studies should consider alternative methods of administration (e.g., inhalation or teas), simplify protocols, ensure sufficient participant numbers for statistical significance (with publication potential), or even conduct group sessions.
In the meantime, we welcome any comments or suggestions and encourage you to share this information with others who might be interested. Please feel free to reach out to us at elaine.perry@ncl.ac.uk.
Mini Experiment
Scientific Research in Junior Herbalist Club!
Dilston Physic Garden mini-experiment in Junior Herbalist Club
In March 2023 we conducted a mini-experiment during Junior Herbalist Club at Dilston Physic Garden, under the direction of Professor Elaine Perry. Its aim was to discover if Lemon Balm / Melissa (Melissa officinalis) essential oil enhances memory.
Participants. 10 members of Davina Hopkinson’s Junior Herbalist’s Club agreed to take part in a 20 minute experiment. Intervention. Participants were divided into two groups, A and B. Group A was asked to rub 1-2 ml of almond oil, and Group B 3% melissa essential oil diluted in almond oil, on their hands and lower arms.
Assessment. After 15 mins a sequence of 8 digits was read out and both groups were then asked to write down what they remembered. Outcome. All were assessed for the number of correct answers, and if the answers were in correct order. Results: Correct digits: A–5,6,6,6,8 and B–6,7,7,8,8. Order correct: A-1 and B-5.
Conclusion. While numbers don’t support statistics, there were more correct digits in Group B, and all in B got the correct digit order, compared to 1 in A. So the trend was towards better recall in Group B, i.e. those who were using melissa essential oil compared to just almond oil.
Comments. No adverse or side-effects reported, except one in B complained of a headache. Aroma from B permeated the room, so A were also exposed to Melissa and could have absorbed it via inhalation, though the dose would have been minimal compared to direct application on skin. Future studies would benefit from separate rooms and increasing the numbers for statistical analysis. The experiment was considered fun and there could be other experiments like this for the young on effects of medicinal plants to help them see how the scientific method can back up plant medicine today.
Our Research
Our Clinical Research Approach
At the Dilston Physic Garden charity, we are dedicated to exploring safe, science-backed plant medicines that have demonstrated evidence of enhancing cognitive functions, such as memory and sleep.
All volunteers participating in our trials are under the supervision of a medical herbalist registered with the National Institute of Medical Herbalists, and each study is reviewed by our Ethics Board. Rather than conducting large-scale, multi-centre trials, we focus on small but statistically valid pilot trials. These trials incorporate both objective measures and self-assessment tools, allowing participants to reflect on their personal experiences. For instance, our 2019 Dream Club pilot study, utilised self-assessment as a key component.
Our studies are open to adults (over 18) with normal mental health. Participants voluntarily take a safe medicinal plant preparation once or twice a day for a set period (weeks or months). Throughout the trial, they complete self-assessment forms or online evaluations before, during, and after the trial period. To ensure unbiased results, volunteers can be randomly divided into two groups—one taking the plant medicine and the other a placebo or plant medicine with opposing effect. Some may participate in a crossover study where all volunteers take both the plant medicine and placebo/opposing plant medicine at different times, sometimes without knowing which they are taking (‘blind’). We aim to publish all our findings in peer-reviewed scientific journals.
If you’re interested in participating in one of our studies, donating to support our research, or volunteering to help design and conduct meaningful studies, please contact us at info@dilstonphysicgarden.com.
Medicinal Plants for Memory
Why Medicinal Plants for Memory?
There are prescription drugs derived from plants that are used to treat cognitive decline in Alzheimer’s disease. For example, galantamine is derived from compounds found in the bulbs of snowdrops and daffodils (though caution is advised as snowdrop bulbs are poisonous if ingested!). However, for those experiencing normal, mild memory impairments—some of which may be early indicators of more serious issues—no approved medications or preventive treatments currently exist.
Individuals concerned about memory loss may want to explore alternative options, including physical and psychological strategies, as well as the regular use of brain boosting medicinal plants. Several plants that grow in the UK have demonstrated memory enhancing properties. These medicinal plants are supported by both traditional evidence, based on centuries if not thousands of years of use by humans, and cutting-edge scientific evidence, grounded in modern laboratory research and controlled clinical trials.
While no single plant extract has yet been universally accepted in mainstream medical practice for memory, ongoing research, standardised extracts, accurate dosing, and long-term studies are paving the way. Our trials, conducted in collaboration with practicing medical herbalists, the Royal Botanic Gardens Kew, North East Universities, and other organisations in the UK, focus on bringing this research into the community. For instance, the results of our first trial, conducted in collaboration with medical herbalists and the BodyWorks Centre in Hexham, Northumberland, and showed that the plant medicine improved word recall by over 50% in participants aged under 63.
Our Memory Research – below is some of the memory plant medicine research we have led or were involved with:
Howes MR, Perry NSL, Vásquez-Londoño C, Perry EK. Role of phytochemicals as nutraceuticals for cognitive functions affected in ageing. Br J Pharmacol. 2020 Mar;177(6):1294-1315. doi: 10.1111/bph.14898. Epub 2020 Feb 3. PMID: 31650528; PMCID: PMC7056459.
Perry NSL, Menzies R, Hodgson F, Wedgewood P, Howes MR, Brooker HJ, Wesnes KA, Perry EK. A randomised double-blind placebo-controlled pilot trial of a combined extract of sage, rosemary and melissa, traditional herbal medicines, on the enhancement of memory in normal healthy subjects, including influence of age. Phytomedicine. 2018 Jan 15;39:42-48. doi: 10.1016/j.phymed.2017.08.015. Epub 2017 Aug 18. PMID: 29433682.
Perry E, Howes MJ. Medicinal plants and dementia therapy: herbal hopes for brain aging? CNS Neurosci Ther. 2011 Dec;17(6):683-98. doi: 10.1111/j.1755-5949.2010.00202.x. Epub 2010 Oct 18. PMID: 22070157; PMCID: PMC6493900.
Scholey AB, Tildesley NT, Ballard CG, Wesnes KA, Tasker A, Perry EK, Kennedy DO. An extract of Salvia (sage) with anticholinesterase properties improves memory and attention in healthy older volunteers. Psychopharmacology (Berl). 2008 May;198(1):127-39. doi: 10.1007/s00213-008-1101-3. Epub 2008 Mar 19. PMID: 18350281.
Tildesley NT, Kennedy DO, Perry EK, Ballard CG, Wesnes KA, Scholey AB. Positive modulation of mood and cognitive performance following administration of acute doses of Salvia lavandulaefolia essential oil to healthy young volunteers. Physiol Behav. 2005 Jan 17;83(5):699-709. doi: 10.1016/j.physbeh.2004.09.010. PMID: 15639154.
Tildesley NT, Kennedy DO, Perry EK, Ballard CG, Savelev S, Wesnes KA, Scholey AB. Salvia lavandulaefolia (Spanish sage) enhances memory in healthy young volunteers. Pharmacol Biochem Behav. 2003 Jun;75(3):669-74. doi: 10.1016/s0091-3057(03)00122-9. PMID: 12895685.
Perry NS, Bollen C, Perry EK, Ballard C. Salvia for dementia therapy: review of pharmacological activity and pilot tolerability clinical trial. Pharmacol Biochem Behav. 2003 Jun;75(3):651-9. doi: 10.1016/s0091-3057(03)00108-4. PMID: 12895683.
Perry NS, Houghton PJ, Jenner P, Keith A, Perry EK. Salvia lavandulaefolia essential oil inhibits cholinesterase in vivo. Phytomedicine. 2002 Jan;9(1):48-51. doi: 10.1078/0944-7113-00082. PMID: 11926204.
Perry NS, Houghton PJ, Sampson J, Theobald AE, Hart S, Lis-Balchin M, Hoult JR, Evans P, Jenner P, Milligan S, Perry EK. In-vitro activity of S. lavandulaefolia (Spanish sage) relevant to treatment of Alzheimer’s disease. J Pharm Pharmacol. 2001 Oct;53(10):1347-56. doi: 10.1211/0022357011777846. PMID: 11697542.
Perry NS, Houghton PJ, Theobald A, Jenner P, Perry EK. In-vitro inhibition of human erythrocyte acetylcholinesterase by Salvia lavandulaefolia essential oil and constituent terpenes. J Pharm Pharmacol. 2000 Jul;52(7):895-902. doi: 10.1211/0022357001774598. Erratum in: J Pharm Pharmacol 2000 Dec;52(12):203. PMID: 10933142.
Perry EK, Pickering AT, Wang WW, Houghton PJ, Perry NS. Medicinal plants and Alzheimer’s disease: from ethnobotany to phytotherapy. J Pharm Pharmacol. 1999 May;51(5):527-34. doi: 10.1211/0022357991772808. PMID: 10411211.
Perry EK, Pickering AT, Wang WW, Houghton P, Perry NS. Medicinal plants and Alzheimer’s disease: Integrating ethnobotanical and contemporary scientific evidence. J Altern Complement Med. 1998 Winter;4(4):419-28. doi: 10.1089/acm.1998.4.419. PMID: 9884179.
Wake G, Court J, Pickering A, Lewis R, Wilkins R, Perry E. CNS acetylcholine receptor activity in European medicinal plants traditionally used to improve failing memory. J Ethnopharmacol. 2000 Feb;69(2):105-14. doi: 10.1016/s0378-8741(99)00113-0. PMID: 10687867.
