digitspan

Digit span is a common cognitive task used in neuropsychological assessment to evaluate working memory and attention. In its standard form, an examiner orally presents sequences of digits, and the participant repeats them either in the same order (digit span forward) or in reverse order (digit span backward).

Sequences begin with two digits and increase by one digit after each correct trial, with the test typically ending after two consecutive errors at a given length. The longest sequence accurately recalled or the total number of digits recalled is recorded as the raw score. Many standardized batteries, notably the Wechsler scales, include Digit Span as a subtest, and its scores are often age-adjusted with scaled scores or index scores to facilitate interpretation across populations.

Forward span primarily measures attention and short-term memory for auditory-verbal information, while backward span places greater demands on working memory and mental manipulation. The two tasks are commonly administered together to provide a broader assessment of verbal working memory.

Interpretation of results requires consideration of factors such as education, language background, and hearing ability, as these can influence performance. Digit span is a component of broader cognitive assessment and does not, on its own, diagnose a medical or neurological condition. Variants and norms exist across different tests and populations to support interpretation in clinical and research contexts.