title: Individual differences in rate of encoding predict estimates of visual short-term memory capacity (K).
abstract: The capacity of visual short-term memory (VSTM) is commonly estimated by K scores obtained with a change-detection task. Contrary to common belief, K may be influenced not only by capacity but also by the rate at which stimuli are encoded into VSTM. Experiment 1 showed that, contrary to earlier conclusions, estimates of VSTM capacity obtained with a change-detection task are constrained by temporal limitations. In Experiment 2, we used change-detection and backward-masking tasks to obtain separate within-subject estimates of K and of rate of encoding, respectively. A median split based on rate of encoding revealed significantly higher K estimates for fast encoders. Moreover, a significant correlation was found between K and the estimated rate of encoding. The present findings raise the prospect that the reported relationships between K and such cognitive concepts as fluid intelligence may be mediated not only by VSTM capacity but also by rate of encoding.
authors.affiliation: Department of Psychology, Simon Fraser University.
authors.forename: Ali
authors.initials: A
authors.lastname: Jannati
authors.affiliation: Department of Psychology, Simon Fraser University.
authors.forename: John J
authors.initials: JJ
authors.lastname: McDonald
authors.affiliation: Department of Psychology, Simon Fraser University.
authors.forename: Vincent
authors.initials: V
authors.lastname: Di Lollo
mesh_terms: D000704:Analysis of Variance; D001288:Attention; D005260:Female; D006801:Humans; D007206:Individuality; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010470:Perceptual Masking / Q000502:physiology; D010775:Photic Stimulation; D013334:Students; D014495:Universities; D014796:Visual Perception / Q000502:physiology*