Short-term recognition memory for single letters and phonemic similarity of retroactive interference

Copying 12 letters produces more retroactive interference in recognition memory for a single letter when the interference letters possess a vowel sound in common with the letter to be remembered than when they do not. Compared to interference lists that do not include the presented letter, inclusion in the interference list of the letter to be remembered improves recognition memory when the other interference letters have no vowel sound in common with the letter to be remembered, but not otherwise. False recognition rates are greater when the test letter contains a vowel sound in common with the presented letter than when the vowel sounds of these two letters are different. The findings are in complete accord with analogous findings for short-term recall and indicate that short-term recognition memory uses the same phonemic-associative memory system as short-term recall.     

Negative recency and event-dependence

In a two-choice situation with event-probabilities of 0.67 and 0.33, recency effects were studied as a function of (a) event-dependence and (b) fore-knowledge of event-probabilities. The following conclusions are drawn: (1) Belief in some kind of event-dependence is a necessary condition for the occurrence of negative recency; (2) Foreknowledge of the event-probabilities does not affect recency phenomena; (3) The behaviour of subjects in the two-choice situation, is less irrational than some writers have claimed.     

Memory for the pitch of a tone

Observers attempted to detect the presence of a pitch difference between two successive tones. The percentage of correct judgments was equivalent for tones separated by .95, 4.5, and 8.9 sec. There was a general increase in reports of a pitch difference with increased intertone interval, which is interpreted as arising from hypothesized shifts in the neural locus of the first stimulus during the intertone interval.     

Classification and identification thresholds for three types of verbal materials

The first two experiments found thresholds for classification into one of three categories of English words, Turkish words, and letter alternations to be significantly lower than thresholds for the identification of the specific items; parallel results were found with the two methods of measurement employed. Both thresholds were lowest for English words, and classification thresholds were lower for Turkish words than for letter alternations, but the identification thresholds of these two kinds of materials showed a reversal. The third experiment found classification thresholds for the same three types of materials to be higher than either of two three-choice identification thresholds, one a choice among three sametype items and the other, a choice among one English word, one Turkish word, and one letter alternation.     

Visual and acoustic confusability a visual search task

Visual and acoustic confusability between a target item and background items was varied in a visual search task. Visual confusability was a highly significant source of difficulty while acoustic confusability had no effect. The results do not seem to be interpretable within a theory which assumes compulsory auditory encoding of visual information.