William J. Gavin

Development of Error‐Monitoring Event‐Related Potentials in Adolescents

Abstract: In order to study the maturation of neurobehavioral systems involved in affect regulation and behavioral choices during adolescence, we examined brain activity associated with response monitoring and error detection using event‐related potentials (ERPs). In a visual flanker test, trials with incorrect responses elicit ERP components including an error‐related negativity (ERN) and a later error‐positivity (Pe). We examined the amplitude and latency of the ERN and Pe of incorrect responses in 124 children from 7 to 18 years of age. The ERN amplitude in error trials increased with age although this was qualified by a nonlinear change. The quadratic distribution of the ERN indicated an initial drop in amplitude (lowest at age 10 for girls; age 13 for boys) with a subsequent rise through adolescence. The Pe amplitude did not change with age. Results are discussed with respect to continued maturation of the anterior cingulate cortex and possible influences on adolescent behaviors.

Differentiating specific language impairment from normal language development using grammatical analysis

The present investigation sought to determine whether preschool children with specific language impairment (SLI) could be differentiated from an age-matched sample of typically developing children on the basis of grammatical features displayed within a 20-min sample of conversational language. Language samples from 47 children, 24–50 months of age, described in a previous study (Klee, Schaffer, May, Membrino and Mougey (1989) were analysed using the LARSP framework (Crystal, Fletcher and Garman, 1989). Composite variables were created from the original LARSP categories and transformed into ratios to adjust for the differing number of utterances in each transcript. A discriminant function which optimized the differences between the two groups was then derived from the grammatical analysis. In addition to age and a constant, the function contained three linguistic variables: stage I-major utterances, three-element NPs and VP errors. The outcomes of the discriminant function and the clinical diagnosis were i...