001 (S) S: Significant, SD: Standard deviation, AVLT: Auditory verbal learning test, VFT: Verbal fluency test, VRT: Visual reproduction test, WDST: Working
digit span test, VST: Validation span test, IQR: Interquartile range
The
Digit Span subtest is a two-part instrument designed to assess working memory capacity (Wechsler, 2005).
The Ascending Series Method is the simplest method and a variation of it is used for the
Digit Span subtests of the Wechsler intelligence scales.
There are two subsets of
digit span of WAIS-R, digits forward (DSF) and digits backward (DSB).
The
digit span was taken as the maximum length at which the participants could recall at least two out of three series with no errors (see Sebastian & Hernandez-Gil, 2012).
Stroop test score and P300 amplitude in the right parietal location,
digit span forward score and P300 amplitude in the left central and middle parietal locations, and
digit span backward score and P300 amplitude in the left occipital area were found to be positively correlated.
Neuropsychological assessments used in this study included the
digit span forward test (25) and the Trail Making Test part A (26) for testing attention and concentration; Trail Making Test part B, (26) the
digit span backward test (25) and the Stroop Colour Test (27) for executive function; and verbal learning and memory test in Hindi.
The
digit span has two parts: forwards digit recall, where participants are asked to recall digits in order of presentation; and, backwards digit recall, where participants are asked to recall digits in reverse order of presentation.
All the elderly, from the EG and the CG, submitted to the application of the instruments to evaluate executive functions, in the following order:
Digit Span (DDO and DIO); Vocabulary (V); Block Design (BD); Coding (Cd); Symbol Search (SS); Letter-Number Sequencing (LNS); Rey Complex Figures (RCF); Sternberg Paradigm; Verbal Fluency (animal category); F-A-S; Rey Auditory-Verbal Learning Test (RAVLT); Stroop Test--Colors and Words; Go-No-Go Tasks; Wisconsin Card Sorting Test (WCST).
Two of the most reliable measures of the phonological loop and verbal working memory capacity that are widely used in studies are forward
digit span and non-word repetition tasks.
Forward and reverse
digit span was used to measure working memory.
The neuropsychological battery consisted of the
digit span forward and backward tasks, the Stroop Color Word Test, the Trail Making Test (TMT), and the Controlled Oral Word Association Test (COWAT).