Learning Disability Subtypes and the Role of Attention During the Naming of Pictures and Words: An Event-Related Potential Analysis

Abstract

The role of attention in the processing of pictures and words was investigated for a group of normally achieving children and for groups of learning disability sub-types that were defined by deficient performance on tests of reading and spelling (Group RS) and of arithmetic (Group A). An event-related potential (ERP) recording paradigm was employed in which the children were required to attend to and name either pictures or words that were presented individually or in superimposed picture-word arrays that varied in degree of semantic relation. For Group RS, the ERP waves to words, both presented individually or attended in the superimposed array, exhibited reduced N450 amplitude relative to controls, whereas their ERP waves to pictures were normal. This suggests that the word-naming deficiency for Group RS is not a selective attention deficit but rather a specific linguistic deficit that develops at a later stage of processing. In contrast to Group RS and controls, Group A did not exhibit reliable early frontal negative waves (N280) to the super-imposed pictures and words, an effect that may reflect a selective attention deficit for these children that develops at an early stage of visuo-spatial processing. These early processing differences were also evident in smaller amplitude N450 waves for Group A when naming either pictures or words in the superimposed arrays.

Event-Related Brain Potentials during a Semantic Priming Task in Children with Learning Disabilities Not Otherwise Specified

“…By contrast Ctrl group displayed larger P200 amplitudes in response to related than to unrelated word pairs, which was mainly observed over the frontal regions, as found previously in normal readers [34]. This group difference at P200 has been found in other studies using children with Specific LD i.e., reading disabled children [37]. Enhanced P200 responses have often been observed for words in constraining sentence contexts, perhaps reflecting a preparatory attentional response elicited by language contexts that generate a strong expectation for particular upcoming stimuli [28], [29], [51].…”

“…Although statistically significant differences have not been shown between groups and between experimental conditions regarding behavioral results, in general children with LD Not Otherwise Specified show a lower number of correct answers. One explanation that would account for the bare differences in the N400 effect in this study and even others [35], [36], [40] whose results are not consistent [37], [39], may be that the greater amplitude of P200 to unrelated stimuli makes it remain above the baseline that would be the beginning of N400. Therefore, by comparing both conditions (related vs. non-related), differences in amplitude would be reduced between the conditions of this latter component.…”

“…Distinct cognitive profiles were observed in LD reading- and arithmetic-disabled children in one ERP semantic priming study [37]. These subgroups were defined by deficient performance on tests of reading and spelling (Group RS) and arithmetic (Group A).…”

Electroencephalographic characterization of subgroups of children with learning disorders

“…Subtypes in a group of children with LD have been defined on the basis of the patterns of deficits in their cognitive abilities, and differences have been found between them in terms of their EEG activity in event related potentials [23,24,25]. Jäncke and Alahmadi [20] explored differences in the resting state EEG using an independent component analysis, between healthy control children, children with verbal disabilities, and children with LDNOS; they found differences in EEG oscillations in an eyes open condition in the left temporal cortex in delta, theta, alpha and beta-1 frequencies as well as in alpha in an eyes closed condition in the mesial paracentral cortex extending into the superior parietal lobe.…”

An event-related potential study of semantic style-match judgments of artistic furniture

“…This N400 waveform represents the semantic relationship between the current stimulus and the preceding context. Several studies of the N400 waveform were undertaken to index semantic integration processes, using the final word of a sentence as the stimulus (Andrews et al, 1993;Kutas and Hillyard, 1980;McCarley et al, 1991;Mitchell et al, 1991), picture-words (Greenham et al, 2003;Mathalon et al, 2002), pairs of words (Grillon et al, 1991;Koyama et al, 1994;Khateb et al, 2007;Núñez-Peña and Honrubia-Serrano, 2005;Pritchard et al, 1991;Weisbrod et al, 1998), pairs of pictures (Barrett and Rugg, 1990;Bobes et al, 1996;Ellis and Nelson, 1999;Guerra et al, 2009;Proverbio et al, 2007), and even incongruent human actions (Proverbio and Riva, 2009;Wu and Coulson, 2007) when the presented objects did not fit into any previously established semantic category.…”