Withania has a long history of traditional medicine use as a tonic for improving memory and mild anxiety This month we take a look at a recent trial investigating how effective it is at improving aspects of memory.
Mild cognitive impairment is frequently associated with the aging process and one of the herbs traditionally used in Ayurvedic medicine to enhance memory and concentration is Withania somnifera.
To measure effectively which parts of a memory are affected by cognitive decline researchers use the Weschler Memory Scale III. For measurement purposes, memory is commonly subdivided into the following types: immediate memory is the ability to retain information for a few seconds, whilst general memory relates to individually experienced events that can be assessed such as delayed recall of word lists, geometric patterns, faces or text and working memory refers to the ability to store information in the immediate term as it is being received from sensory inputs such as the eyes, ears, and other sense organs. This third memory sub type is needed for rapidly sorting, processing and assembling bits of information for better interpretation - making meaning out of small pieces of data.
Mild cognitive impairment can typically begin to occur around 45 years of age in prone individuals. It is normally managed with pharmaceutical drugs, however these can produce unwanted side effects, therefore the researchers sought to investigate whether complementary medicine treatments could offer a safer, yet still effective, alternative. They chose to investigate Withania somnifera, a commonly used herbal product traditionally utilised for improving aspects of memory.(1) The researchers conducted a randomised double-blind, placebo-controlled, pilot clinical trial to determine whether Withania somnifera (Ashawaganda), could be a safe and efficacious alternative for improving cognition function and memory in adults aged 35 years or older.
After baseline data was collected, 50 participants, were randomly assigned by computer-generated allocation, to receive either 300 mg of Withania somnifera root extract twice a day for eight weeks, or a placebo - matched control. Participants, staff and statisticians were all blinded as to treatment allocation and unblinding occurred only after the study was completed. Results were measured at one month and at study close.(1)
At study completion the intervention group had significant improvements in immediate recall general memory as reflected in their improvements in logical memory (P = 0.007), verbal paired associates (P = 0.042), face recognition (P = 0.020) and family pictures (P = 0.006) in subtest scores on the Wechsler Memory Scale III.(1) The treatment group also displayed significant improvements in executive function, sustained attention, and information-processing speed as indicated by their scores on the Eriksen Flanker task (P = 0.002), Wisconsin Card Sort test (P = 0.014), Trail-Making test part A (P = 0.006), and the Mackworth Clock test (P = 0.009) when compared to placebo. Side effects were uncommon, mostly mild, transient and reversible.(1)
This study provides promising initial evidence that doses of Withania somnifera equal to 600 mg daily may be effective in enhancing both immediate recall and general aspects of memory in people with mild cognitive impairment. This dose may also enhance executive functioning, increase attention span and improve information processing speed.(1)
References Choudhary D, Bhattacharyya S, Bose S. Efficacy and Safety of Ashwagandha (Withania somnifera (L.) Dunal) Root Extract in Improving Memory and Cognitive Functions. Journal of Dietary Supplements. 2017 Nov 2;14(6):599-612.