title: Fan effects reveal position-specific numerical concepts.
abstract: We examined associative interference (i.e., fan) effects to determine if the numerical concepts mediating numerical fact retrieval can be position specific. Participants memorized 15 "diamond arithmetic" facts (e.g., 3 [symbol: see text] 5 = 97; Whalen, 1997) involving five different operands. Ignoring operand position (i.e., left vs. right), each operand appeared equally often across items (i.e., position-independent fan was constant). In contrast, position-specific fan values varied across items (e.g., 2 appeared five times as the left operand, but once in the right position; 3 appeared four times as the left operand, and twice as the right operand, etc). Thus, we expect a fan effect only if the concepts activated by arithmetic operands are position specific. Results indicated that position-specific fan was an excellent predictor of trials to criterion, error rate, and latency. The concepts mediating number fact retrieval can be position specific.
authors.affiliation: Department of Psychology, University of Saskatchewan, 9 Campus Drive, Saskatoon, Saskatchewan, S7N 5A5. thp849@duke.usask.ca
authors.forename: T L
authors.initials: TL
authors.lastname: Phenix
authors.forename: J I
authors.initials: JI
authors.lastname: Campbell
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention; D003210:Concept Formation; D005260:Female; D006801:Humans; D008297:Male; D008433:Mathematics; D011939:Mental Recall; D011340:Problem Solving