Reading Ability and Semantic Processing: Isolating Speed of Access

Although much attention has focused on the efficiency of access to semantic information as a determinant of reading ability, previous research has confounded information access and decision processes. The authors used a matching task to study the time course of semantic access among college students. They studied the time course of processing by varying the stimulus onset between the two members of a stimulus pair. Semantic encoding functions obtained from this paradigm were used to isolate semantic access from the decision component of the matching task. Regression analyses indicated that the often-obtained correlation between speed of semantic processing and measures of reading ability is based on unique contributions from both semantic access and decision processes. The results undermine the hypothesis that the efficiency of access to semantic codes is a relatively age-invariant contributor to individual differences in reading.