Alzheimer’s disease is a progressive degenerative disease of the brain that gradually deteriorates memory, attention, thinking and reasoning, plaining and performing familiar tasks, decision-making, behavioural patterns, and personality. It also causes abnormal gait patterns and muscular weakness or imbalance. At first, Alzheimer’s disease could only be diagnosed as dementia, a clinical illness marked by significant progressive cognitive impairment across multiple domains or behavioural symptoms severe enough to have a noticeable functional impact on day-to-day functioning. The main characteristic that sets dementia apart from moderate cognitive impairment is the loss of independence experienced by a person who has dementia. Every three seconds, someone in the world gets dementia. In 2020, there will be more than 55 million dementia sufferers worldwide. Every 20 years, this number will nearly double, rising to 78 million in 2030 and 139 million in 2050. Most of the growth will occur in underdeveloped nations. By 2050, 71% of dementia patients would reside in low- and middle-income nations, up from 60% currently. Numerous illnesses and traumas to the brain can lead to dementia. The most prevalent type of dementia, accounting for 60–70% of cases, is Alzheimer disease. One of the main causes of disability and dependency among older adults worldwide, Alzheimer’s disease is currently the seventh greatest cause of death. Globally, there are more than 10 million new cases of dementia annually, or one new case every 3.2 seconds. The abnormal buildup of tau protein tangles inside brain cells and amyloid protein plaques surrounding brain cells is what causes Alzheimer’s disease. Even though the precise cause of this process is unknown, it starts years before any symptoms show up. The synthesis of chemical messengers, or neurotransmitters, is reduced in affected brain cells. involved the passage of neural signals between brain cells. Acetylcholine levels are consistently low in AD patients. The part of the brain that is typically in charge of memories begins to diminish as the brain ages. When the person reaches age 65, the symptoms worsen every five years. Around age 40, 1 in 20 people may have young or early-onset Alzheimer’s. When a large number of their generational family members have dementia at an early age, the individual is at extremely high risk.  A sedentary lifestyle, loneliness or social isolation, untreated depression (although depression can also be a sign of Alzheimer’s disease), and hearing loss are additional risk factors for the condition. Every stage of Alzheimer’s disease begins gradually, with some difficulty performing everyday tasks, and gets worse over time as the stages progress. A degenerative neurological condition, Alzheimer’s disease can lead to several problems, such as: Cognitive challenges: As Alzheimer’s progresses, patients may have memory loss, difficulty paying bills, and difficulty repeating questions. Changes in behaviour: Individuals with Alzheimer’s disease may exhibit pacing, wandering, agitation, and odd behaviours. Depression: Mood swings, sleep issues, and social disengagement are all symptoms of depression, which is prevalent in Alzheimer’s patients. Physical changes: As the illness worsens, bodily abilities including swallowing, balance, and bladder control may be impacted by brain changes. Other health issues including inhaling food or liquid into the lungs, infections like pneumonia, fractures and falls, bedsores, dehydration, and dental issues like mouth sores or tooth rot can result from this. Hallucinations: As Alzheimer’s disease progresses, delusions and hallucinations may manifest. There are various physiotherapy interventions such as strengthening, gait training, coordination training are given to the patient with AD. Currently TDCS (transcranial direct current stimulation) a non-invasive technique is used to improve the memory and cognition. Therefore, the current study is designed to compare the effect of TDCS combined with cognitive brain training exercises and tdcs only.