Effects of Transcranial Direct Current Stimulation Associated With Cognitive Training in Alzheimer's Disease

The Trail Making Test (TMT) will be administered (Reitan, 1958). From a clinical point of view, TMT is widely used as an indicator of brain dysfunction. TMT is divided into two parts, TMT-A and TMT-B. In the first, circles numbered 1 to 25 following the randomly arranged numerical sequence should be connected, time taken and considered, ie the task should be performed as soon as possible. In the TMT-B task, the connection must alternate between numbers and letters. The TMT (AB) scores consist of the time taken to complete each part, other derived scores are used, such as the difference score (TMT-B - TMT-A) and the ratio score (TMT-A) / TMT- B) (Llinàs-Reglà et al, 2015).

The Tower of London (Shallice, 1982) has been used in studies to evaluate executive function in elderly with AD (Satler, Guimarães, Tomaz, 2016). Tower of London is made up of three vertical pins of different heights and three colored spheres, with a hole in the center to fit the pins. The goal is to move them to reproduce, in a given number of moves, the position of a presented target figure. There are 15 problems with increasing difficulty and reduced possibilities for moving parts. Three attempts to resolve the issue are allowed. Will be evaluated: total and average execution time, and total score, obtained by the sum of the points of each step, ranging from 0 to 3.

Disability Assessment for Dementia (DAD) (Gauthier, et al., 1997; Gélinas et al., 1999). The DAD comprises 17 items that assess ADLs and 23 items that assess instrumental ADL (iADL) and leisure activities. In the category related to ADLs are evaluated hygiene, dressing, undressing, continence and food. IADL assessment and leisure activities consist of tasks related to meal preparation, phoning, sightseeing, finances and correspondence, medication and leisure, and housework (Feldman et al. (2001; Suh et al., 2004). maximum score is 100, lower scores indicate higher level of impairment (Bahia et al., 2010).

This outcome will be assessed with the Neuropsychiatric Inventory Questionnaire (NPI-Q; Kaufer et al., 2000). This instrument consists of a self-administered caregiver scale and provides information on 12 characteristic behavioral and psychological symptoms in patients with dementia. The severity level will be identified (1 = mild, 2 = moderate, 3 = severe). The overall severity score ranges from 0 to 36, with zero indicating no neuropsychiatric symptoms. The reliability and validity of this modified NPI score have been previously established (NPI-Q; Kaufer et al., 2000).

The Canadian Occupational Performance Measure (COPM) (Law et al., 2009) will be used to assess occupational performance, ie engagement in daily activities. The COPM is can be applied with the patient or caregiver, following four steps, firstly it seeks to identify which areas of occupational performance are impaired, ie, which occupations are compromised, and then assign a value from 1 to 10 to measure the degree of importance that the activities listed have for the interviewee or caregiver. Next, five of these activities are organized by priority, and each of them should be assigned a value between 1 and 10 to describe the interviewee's performance and satisfaction respectively. In the end, the averages of performance and satisfaction are calculated.