This is an experimental study conducted at the SGT Medical College Hospital & Research Institute, Gurugram Haryana, India. After receiving Institutional Ethical Clearance the study was initiated. Thirty subjects who have mild cognitive impairment having MoCA scores between 22 and 26 [13] of either gender ranging from 60 to 70 years of age group [18] with a minimum education of 12th class who can understand simple English words and follow verbal instruction were included in the study. Those who were having any neurological disorders in the brain and spinal cord such as Alzheimer’s disease (AD), Lewy body disease, stroke (CVA), Huntington’s disease, MS, ALS, frontotemporal dementia, and vascular dementia; use of medication known to have a negative impact on cognition (benzodiazepines); use of antipsychotics and cholinesterase inhibitors (CHEIs); current or recent (past 6 months) alcohol or substance use disorder; any behavioral changes like depression, anxiety, stress, other systemic diseases likely to impair cognition, such as hypothyroidism, deficiency of folic acid or vitamin B12, or viral infection (syphilis, HIV); vision and speech impairment (aphasia); any sort of musculoskeletal pain; lack of sleep less than 8 h; and nutritional deficiency like-thiamine were excluded [19, 20]. The sample size was calculated using the G- power software with a 10% power and 95% confidence interval.
The samples of 42 subjects were selected from the population on the basis of inclusion and exclusion criteria. Twelve subjects were excluded (not meeting the inclusion criteria) and 4 subjects lost follow-up out of 30 subjects. Twenty-six subjects fulfilled the protocol and were equally divided into two groups (Fig. 1). Pre readings of Montreal Cognitive Assessment (MoCA) were taken for both the groups at baseline, i.e., before starting the intervention. Both the groups received different cognitive strategies and aerobic exercise. Cognitive treatment protocol of 40 min per day, at a frequency of 2 sessions per week, for a period of 4 weeks [21], was given by the researcher in her supervision for both groups, and aerobic exercise was also performed for 15 min per day, for a period of 4 weeks. At the end of the 4th week, post readings were taken through Montreal Cognitive Assessment (MoCA).
Outcome measures
Montreal Cognitive Assessment (MoCA). This scale has been used in the population of normal individuals, mild cognitive impairment, stroke, multiple sclerosis, Parkinson’s disease, traumatic brain injury, and those who have cognitive decline. The scale consists of 8 items that are scores range between 0 and 30. A score of 26 or over is considered to be normal. MoCA scale is a valid scale in detecting cognitive impairment. It has high sensitivity and specificity, i.e., 100% and 87% respectively [21].
Interventions
Group A (internal cognitive training+ aerobic exercise)
The internal cognitive training (ICT) included mnemonics, chunking, method of loci, story recall, and list/object recall. In mnemonics, participants are asked to recognize the photo and remember the name of that person by self-generating mnemonics; chunking is a process of taking individual pieces of information (chunks) and grouping them into large units; method of memory enhancement uses visualizations with the use of spatial memory; story recall is when reading or listening to a story; it might be helpful to focus on only the key points of the story, this way irrelevant information can be forgotten and the story may simplify and be easier to recall and in last recall the list of things or list of items needed for cooking or shopping, etc. It combines with chunking and method of loci.
Group B (external cognitive training+ aerobic exercise)
The external cognitive training (ECT) included cueing, spaced retrieval, face-name recall, and number recall. Cueing by providing relevant cues at recall can aid retrieval and can be useful when teaching information particularly face-name recall or number recall. Two types of cueing are vanishing cues (cueing with decreasing assistance) or forward cues (cueing with increasing assistance); spaced retrieval helps to aid increase retention of information. This strategy is beneficial for face-name associations, object naming, and memory of object location, face-name recall, present a photograph of the to-be-remembered person. Discuss the photograph and name. Generate mnemonics (or association) that can be used to assist recall. It combines with cueing and spaced retrieval, number recall, and present the to-be-remembered numbers in verbal and written formats. Discuss the number, what it is for, how often it is used, etc., and generate mnemonics (or associations) that can be used to assist recall. It also combines with cueing and spaced retrieval [22, 23].
Aerobic exercise
It includes brisk walking, cycling, jogging, and running for 15 min per day for 4 weeks which is not done under supervision [24].
Statistical analysis
Statistical Analysis was done using the software package SPSS 20.00 for Windows 7 version. The mean and standard deviation of all the variables was calculated. Wilcoxon test was used to compare the mean of data of pre and post-intervention within the group. Mann-Whitney test was used to compare the mean of data of pre and post-intervention between groups A and B. The p-value<0.05 was considered to be statistically significant.
