Unusual modality effects in less-skilled readers.

University students who were skilled or less-skilled readers were compared on tests of auditory information processing and immediate serial recall of auditory and visual digits. Reading skill was defined by performance on a pseudoword reading task. The good readers exhibited typical modality effects with higher recall of auditory than visual items from the last 3 serial positions. On the terminal list item, the less-skilled readers showed a modality effect comparable with that of the skilled readers, but on other list items the modality effect reversed and a visual superiority was obtained. Results were discussed in terms of C. G. Penney's (1989) separate-streams model of short-term verbal memory.

Modality effects in delayed free recall and recognition: visual is better than auditory.

During presentation of auditory and visual lists of words, different groups of subjects generated words that either rhymed with the presented words or that were associates. Immediately after list presentation, subjects recalled either the presented or the generated words. After presentation and test of all lists, a final free recall test and a recognition test were given. Visual presentation generally produced higher recall and recognition than did auditory presentation for both encoding conditions. The results are not consistent with explanations of modality effects in terms of echoic memory or greater temporal distinctiveness of auditory items. The results are more in line with the separate-streams hypothesis, which argues for different kinds of input processing for auditory and visual items.

Modality effects and the structure of short-term verbal memory.

The effects of auditory and visual presentation upon short-term retention of verbal stimuli are reviewed, and a model of the structure of short-term memory is presented. The main assumption of the model is that verbal information presented to the auditory and visual modalities is processed in separate streams that have different properties and capabilities. Auditory items are automatically encoded in both the A (acoustic) code, which, in the absence of subsequent input, can be maintained for some time without deliberate allocation of attention, and a P (phonological) code. Visual items are retained in both the P code and a visual code. Within the auditory stream, successive items are strongly associated; in contrast, in the visual modality, it is simultaneously presented items that are strongly associated. These assumptions about the structure of short-term verbal memory are shown to account for many of the observed effect of presentation modality.

Order information in dichotic memory.

Three experiments were performed using a recognition probe procedure to test the subject's recognition of the order of two items from a dichotically presented list. In all three experiments subjects were unable to recognize simultaneous items as having been simultaneous unless the critical pair was the last pair in the list. In contrast, they were able to identify the order of items not originally presented simultaneously at better than a chance level. Performance did not differ as a function of whether the two critical items were presented to the same or different ears. The data were interpreted as indicating that subjects divide attention between competing inputs in the dichotic memory task and that the eary-by-ear order of report is a result of the format in which the items are stored.

Paired associate and sequential probes in dichotic memory.

Paired associate (PA) and sequential (SQ) probes were compared in two experiments in which lists of four (Experiment I) or five (Experiment II) pairs were presented dichotically. The SQ probe gave higher recall for early list items while the PA probe was superior for the last serial position. The effects of presentation rate and a nonredundant suffix were typical in the PA probe conditions but were not systematic in the SQ conditions. The data were discussed in terms of the sequential association hypothesis and the importance of considering the subject's processing strategies in interpreting rate and interference effects in memory.