The current study investigates whether younger adults process distraction semantically and how age influences the level of distraction processing. In a first experiment, younger adults’ processing of distraction was examined by comparing implicit and explicit memory for that distraction. Then, in a second experiment, younger and older adults’ semantic processing of distractors was directly tested by examining memory for distractors on a conceptually based category-generation task. Younger adults showed equivalent implicit and explicit distractor memory in the first experiment and no conceptual priming for distractors on the category-generation task of the second experiment. Older adults, on the other hand, showed reliable conceptual priming for distractors, and the effect was significantly correlated with age in that group. The results collectively suggest that older, but not younger, adults engage in elaborate processing of irrelevant information, and that this effect is possibly tied to inhibitory control abilities that tend to decrease with age.

The development of category knowledge is in part a function of one's experiences with the world. The types of errors produced during category generation tasks may reveal the boundaries of these experiences and the ways in which they are organized into lexical networks. Examining the errors made by bilingual children with and without language impairment (LI) and bilingual adults may help to distinguish the effects of ability versus experience on the development and organization of lexical-semantic categories. The purpose of this study was to examine the types of errors made by bilingual (Spanish-English) children with (n=37) and without (n=35) LI and bilingual adults (n=26) on category generation tasks in both their languages and at two category levels: taxonomic and slot-filler. Results revealed a main effect for level (taxonomic vs. slot-filler) and error type (semantic vs. other) and suggest that bilingual seven to nine-year-old children's and adults' proportions and types of errors produced on category generation tasks differ significantly based on ability (i.e., TD or LI) but not on experience (i.e., TD or Adults). / text

The research on bilingual language processing explores two main avenues of relevance to the present study: lexico-semantic access and cognitive control. Lexico-semantic access research investigates the manner in which bilingual individuals retrieve single words from their lexical system. Healthy bilingual individuals can manipulate their lexico-semantic access to accommodate settings in which code- or language-switching is expected. Alternatively, they can manipulate their lexico-semantic access to speak only their first (L1) or second (L2) languages. Cognitive control, also known as executive functioning, is closely related to lexico-semantic access. Specifically, bilingual individuals maintain and switch between their languages through a mechanism known as cognitive control. Both cognitive control and lexico-semantic access are important for language processing in healthy bilingual individuals as well as bilingual persons with aphasia (BPWA). However, the extent to which BPWA utilize each of these processes in the production of single words is still unknown. The present study used a method of verbal fluency in the form of a novel modified category generation task to assess the relative contributions of lexico-semantic access and cognitive control in bilingual healthy controls and BPWA.