Working memory, inhibitory control, and reading disability

Abstract

The relationships among working memory, inhibitory control, and reading skills were studied in 966 individuals, 6-49 years old. In addition to a standardized measure of word recognition, they received a working memory (listening span) task in the standard, blocked format (three sets containing two-, three-, or four-item trials) or in a mixed format (three sets each containing two-, three-, and four-item trials) to determine whether scores derived from the standard format are influenced by proactive interference. Intrusion errors were investigated in order to determine whether deficits in working memory were associated with the access, deletion, or restraint functions of inhibitory control. The results indicated that deficits in working memory were characteristic of individuals with reading disabilities at all ages. These deficits may be associated with the access and restraint functions of inhibition. Working memory skills increased until the age of 19. The blocked format showed a gradual decline in adulthood whereas the mixed format did not. The different patterns suggest that the decline in working memory skills associated with aging may result from growing inefficiencies in inhibitory control, and not diminished capacity.

Age, time of testing, and proactive interference.

“…Evaluating the recall measure alone may well be misleading, particularly when assessing group differences in PI when groups may vary in their ability to delete old items (as is the case in the present study; see Chiappe et al, 2000).…”

Control of information in working memory: Encoding and removal of distractors in the complex-span paradigm

“…For instance, in the classic reading-span task, in which participants read sentences and try to remember the last word of each sentence (Daneman & Carpenter, 1980), the non-final words of the sentences are distractors that arguably belong to the task vocabulary (i.e., words), and intrusions of such non-final words have been observed (Chiappe, Hasher, & Siegel, 2000;De Beni & Palladino, 2000;De Beni, Palladino, Pazzaglia, & Cornoldi, 1998). In contrast, more recent versions of complex span use clearly different stimulus categories as memoranda and distractors -for instance, people read sentences and remember lists of letters.…”

Behavioral inhibition in children with learning disabilities

“…For instance, children with RD have to inhibit inadequate grapheme-phoneme correspondences (for instance reading 'p' as 'b' or 'm' as 'n' or 'nam' as 'man'). Failures to inhibit improper (though more dominant) pronunciations might impair word recognition performance in a more profound manner (Chiappe, Hasher, & Siegel, 2000).…”