Memory for Relevant and Irrelevant Information: Evidence for Deficient Inhibitory Processes in Language/ Learning Disabled Children

The present study examined whether language/learning disabled children have greater difficulty than nondisabled children suppressing information that becomes irrelevant during a sentence processing and memory task. During study trials, children were asked to predict and remember the terminal nouns for a series of sentences that highly constrained a terminal noun. For half of the study trials (fillers) the child's prediction was confirmed by presenting the child with the expected ending (e.g., “Butterflies fly by flapping their . . .wings.”). For the remaining study trials (critical trials), however, the sentence ending expected by the child was disconfirmed with a low-probability ending (target noun). Thus, when presented with the sentence, “We made a sandwich with peanut butter and . . . ,” the child's prediction (“jelly”) was disconfirmed with a different ending (“bananas”). Memory for the disconfirmed and target nouns of critical study trials were subsequently tested implicitly with a new sentence-completion task. In this case, memory for disconfirmed and target nouns that had been associated with individual study sentences were measured in terms of priming effects. The analysis of priming effects indicated that language/learning disabled children experienced greater difficulty than nondisabled children inhibiting the activation of irrelevant information (disconfirmed nouns) and sustaining the activation of relevant information (target nouns) during a verbal memory task. These results were discussed in terms of their implications for some of the memory and language difficulties of language/learning disabled children.     

Assessing students' ability to trace matter in dynamic systems in cell biology

College-level biology courses contain many complex processes that are often taught and learned as detailed narratives. These processes can be better understood by perceiving them as dynamic systems that are governed by common fundamental principles. Conservation of matter is such a principle, and thus tracing matter is an essential step in learning to reason about biological processes. We present here multiple-choice questions that measure students' ability and inclination to trace matter through photosynthesis and cellular respiration. Data associated with each question come from students in a large undergraduate biology course that was undergoing a shift in instructional strategy toward making fundamental principles (such as tracing matter) a central theme. We also present findings from interviews with students in the course. Our data indicate that 1) many students are not using tracing matter as a tool to reason about biological processes, 2) students have particular difficulties tracing matter between systems and have a persistent tendency to interconvert matter and energy, and 3) instructional changes seem to be effective in promoting application of the tracing matter principle. Using these items as diagnostic tools allows instructors to be proactive in addressing students' misconceptions and ineffective reasoning.