title: Similarity effects in visual working memory.
abstract: Perceptual similarity is an important property of multiple stimuli. Its computation supports a wide range of cognitive functions, including reasoning, categorization, and memory recognition. It is important, therefore, to determine why previous research has found conflicting effects of inter-item similarity on visual working memory. Studies reporting a similarity advantage have used simple stimuli whose similarity varied along a featural continuum. Studies reporting a similarity disadvantage have used complex stimuli from either a single or multiple categories. To elucidate stimulus conditions for similarity effects in visual working memory, we tested memory for complex stimuli (faces) whose similarity varied along a morph continuum. Participants encoded 3 morphs generated from a single face identity in the similar condition, or 3 morphs generated from different face identities in the dissimilar condition. After a brief delay, a test face appeared at one of the encoding locations for participants to make a same/different judgment. Two experiments showed that similarity enhanced memory accuracy without changing the response criterion. These findings support previous computational models that incorporate featural variance as a component of working memory load. They delineate limitations of models that emphasize cortical resources or response decisions.
authors.affiliation: Department of Psychology, University of Minnesota, 75 East River Road, S251 Elliott Hall, Minneapolis, MN, 55455, USA. jiang166@umn.edu.
authors.forename: Yuhong V
authors.initials: YV
authors.lastname: Jiang
authors.affiliation: Department of Psychology, University of Minnesota, 75 East River Road, S251 Elliott Hall, Minneapolis, MN, 55455, USA.
authors.forename: Hyejin J
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Department of Psychology, University of Minnesota, 75 East River Road, S251 Elliott Hall, Minneapolis, MN, 55455, USA.
authors.forename: Anthony
authors.initials: A
authors.lastname: Asaad
authors.affiliation: Department of Psychology, University of Minnesota, 75 East River Road, S251 Elliott Hall, Minneapolis, MN, 55455, USA.
authors.forename: Roger
authors.initials: R
authors.lastname: Remington
mesh_terms: D000293:Adolescent; D000328:Adult; D000066499:Facial Recognition / Q000502:physiology*; D006801:Humans; D008570:Memory, Short-Term / Q000502:physiology*; D055815:Young Adult
keywords: Change detection; Face memory; Similarity; Visual working memory