[01] Nadia Begum binti Ejaz Ahmad, Faculty of Medicine, Melaka-Manipal Medical College, Manipal Academy of Higher Education (MAHE), Melaka, Malaysia. [02] Nursyameem Safra binti Abdul Khalim, Faculty of Medicine, Melaka-Manipal Medical College, Manipal Academy of Higher Education (MAHE), Melaka, Malaysia. [03] Gur Raj Singh Koushal, Faculty of Medicine, Melaka-Manipal Medical College, Manipal Academy of Higher Education (MAHE), Melaka, Malaysia. [04] Ajanthan Umeshan, Faculty of Medicine, Melaka-Manipal Medical College, Manipal Academy of Higher Education (MAHE), Melaka, Malaysia.

Probiotics have been used in medicine for the treatment of many disorders, such as IBS, type 2 diabetes and severe burns. Probiotics are now also being studied for their effect on the brain, through the ‘gut-brain axis’, and have been studied in many psychiatric disorders and neurodegenerative disorders. They are generally considered safe, but their adverse effects in human subjects is still being studied. Our objective is to compare the effect of food probiotics versus probiotics tablets on short term memory and concentration, and also to identify and document any adverse effect due to probiotics consumption, among undergraduate students in Malaysia. A randomized controlled trial (RCT), parallel design was conducted from September 2019 to October 2019. Purposive sampling was used to select 40 students based on inclusion and exclusion criteria, who were then randomized into two groups of 20 students each. Baseline testing was done with the Human Benchmark Test and TestMyBrain continuous concentration. Each group was then given either the food probiotic or tablet probiotic for 5 days, and the tests were repeated after the 5^th day. The mean difference between the two groups, as well as before and after the intervention was calculated. Chi square test, unpaired and paired t tests were used. Level of significance was set at P < 0.05. Based on the results from our study, there were no significant differences in visual memory, verbal memory, number memory and continuous concentration between intervention and control groups. We found that after 5 days of consuming probiotics, there was an increase in verbal, visual, number memory test scores, as well as continuous concentration scores in both food as well as tablet probiotics. When comparing the scores before and after food probiotics consumption, there were increases in verbal memory, visual memory and number memory, as well as continuous concentration but these were not statistically significant. Additionally, when comparing the scores before and after tablet probiotics, visual memory and continuous concentration had decreased; however, the participants who consumed probiotics for 5 days had higher visual memory and number memory scores than participants in the control group. Based on out study, probiotics can improve short term memory such as verbal, visual and number memory, and continuous concentration, with no significant differences between food and tablet probiotics. The authors recommend food probiotics, due to their improved safety profile and relative economic value, to aid the improvement of short term memory and continuous concentration.

Probiotics, Short-Term Memory, Continuous Concentration, RCT

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