title: False positives in recognition memory produced by cohort activation.
abstract: Cohort theory in spoken-word recognition assumes that a cohort of word candidates consistent with incoming sensory information is activated implicitly as a spoken sound stimulus unfolds over time. Five experiments examined implications of this internal-generation-of-words mechanism. In Experiments 1 and 2, a "base" word was disqualified (the sensory information was no longer consistent with the word) either early or late in the presentation of a spoken stimulus. On a later recognition-memory test, significantly more false-positive errors occurred to base words following presentations of study items that had late, compared to early, disqualification points. Experiments 3-5 tested whether this phenomenon could be accounted for in terms of overlapping features between non-word stimuli and their base words or in terms of a post-identification processing mechanism. Experiment 3 replicated Experiments 1 and 2, and demonstrated that differences in early and late disqualification points for non-word targets, unlike word targets, were not related to false-positive recognition memory errors. The study inter-item interval in Experiment 4 was reduced to 1 s to minimize the role of post-identification processing activities, and the results for both word and non-word targets were consistent with Experiment 3. A word-association task in Experiment 5 revealed that the late non-word derivations used in this research were on the average more effective stimuli than the early non-word derivations in eliciting their base words. However, even when comparisons were restricted to item sets with early and late non-words that were equally effective in eliciting base words, false-positive recognition memory errors to target words were higher following prior presentations of their late derived non-words than following prior presentations of their early derived non-words.
authors.affiliation: Department of Psychology, University of Nevada, Reno 89557, USA.
authors.forename: W P
authors.initials: WP
authors.lastname: Wallace
authors.forename: M T
authors.initials: MT
authors.lastname: Stewart
authors.forename: H L
authors.initials: HL
authors.lastname: Sherman
authors.forename: M D
authors.initials: MD
authors.lastname: Mellor
mesh_terms: D000328:Adult; D001288:Attention; D005260:Female; D006801:Humans; D008297:Male; D011939:Mental Recall; D010153:Paired-Associate Learning; D012153:Retention, Psychology; D013018:Sound Spectrography; D013061:Speech Acoustics; D013067:Speech Perception; D014706:Verbal Learning