Research on sources of individual difference in parental Infant-Directed Speech (IDS) is limited and there is a particular lack of research on fathers' compared to mothers' speech. This study examined the predictive relations between infant characteristics and variability in paternal lexical diversity (LD) in dyadic free play with two-year-olds (M…

Labels for scores stemming from intelligence tests have been employed since their inception in the United States. The purpose of this study was to systematically identify and document score labels for IQs used during the past 102 years. Using pairs of reviewers, score labels from 40 tests were reviewed, and 61 unique labels were identified.…

Lexical access is a core component of word processing. In order to produce or comprehend a word, language users must access word forms in their mental lexicon. However, despite its involvement in both tasks, previous research has often studied lexical access in either production or comprehension alone. Therefore, it is unknown to which extent…

The home literacy environment is a well-established predictor of children's language and literacy development. We investigated whether formal, informal, and indirect measures of the home literacy environment predict children's reading and language skills once maternal language abilities are taken into account. Data come from a longitudinal study…

Research on secular trends in mean intelligence test scores shows smaller gains in vocabulary skills than in nonverbal reasoning. One possible explanation is that vocabulary test items become outdated faster compared to nonverbal tasks. The history of the usage frequency of the words on five popular vocabulary tests, the GSS Wordsum, Wechsler…