Time sharing in working memory processing.

Although working memory (WM) is usually defined as a cognitive system coordinating processing and storage in the short term, in most WM models, memory aspects have been developed more fully than processing systems, and many studies of WM tasks have tended to focus on memory performance. The present study investigated WM functioning without focusing exclusively on short-term memory performance by presenting participants with an n-back task on letters, n varying from 0 to 2, each letter being followed by a tone discrimination task involving from one to three tones. Predictions regarding the reciprocal effects of these tasks on each other were motivated by the time-based resource-sharing (TBRS) theoretical framework for WM that assumes the temporal sharing of attention between processing and memory. Although, as predicted, increasing the n value had a detrimental effect on tone discrimination in terms of accuracy and response times, and increasing the number of tones disrupted speed and accuracy on n-back performance, the overall pattern of results did not perfectly fit the TBRS predictions. Nonetheless, the main alternative models of WM do not seem to offer a complete account. The present findings point toward the need to use a larger range of tasks and situations in designing and testing models of WM. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Bizarreness and Typicality Effects of Color on Object Recognition Memory.

The bizarreness effect on object recognition is a strong phenomenon, but its influence has been inconsistent for bizarre object color. In this study, we manipulated three factors in separate experiments to determine whether a color bizarreness effect on object recognition memory would occur and, if not, why. Participants first saw (i.e., learned) object pictures that were either bizarrely or typically colored; they then completed a recognition memory test. In three experiments, we then manipulated (a) degree of color bizarreness (Experiment 1), (b) the orientation task (Experiment 2), and (c) additional demands for object identification (Experiment 3). In Experiment 1, we provided 49 undergraduate participants with object pictures whose colors were typical, moderately atypical, or bizarre and found no color bizarreness effect on recognition memory even for extremely bizarre colors. In Experiment 2, we manipulated the orientation task in that 28 young adult participants expressed their preferences for the pictures on a three-point scale while another 28 participants judged how natural the pictures were. Each orientation task group better recognized typically-colored rather than bizarrely-colored objects (typicality effect). In Experiment 3, we asked 27 young adults to identify the objects during the learning phase to ensure that they paid attention to the objects' bizarre colors; recognition memory was then unaffected by either color bizarreness or typicality. Thus, despite a general bizarreness effect in recognition memory, bizarre colors are less likely to influence object recognition memory.

Homophone Advantage in Sentence Acceptability Judgment: An Experiment with Japanese Kanji Words and Articulatory Suppression Technique.

The purpose of this study was to examine the role and nature of phonology in silent reading of Japanese sentences. An experiment was conducted using a Japanese sentence acceptability judgment task. One important finding was that participants more rapidly rejected homophonic sentences in which one two-kanji compound word was replaced by its homophone word than non-homophonic sentences. In the latter, the word was replaced by a non-homophone spelling control; that is, we observed a homophone advantage. Participants were able to identify the correct word easily through foil's homophonic mate. This indicated that activated phonology played a role in the Japanese sentence acceptability judgment task and it contributed to the error detection/recovery process. Another important finding was that the homophone facilitation effect remained under articulatory suppression. It confirmed that phonology was activated at an early stage as abstract, non-articulatory phonology.

Recalling visual serial order for verbal sequences.

We report three experiments in which participants performed written serial recall of visually presented verbal sequences with items varying in visual similarity. In Experiments 1 and 2 native speakers of Japanese recalled visually presented Japanese Kanji characters. In Experiment 3, native speakers of English recalled visually presented words. In all experiments, items varied in visual similarity and were controlled for phonological similarity. For Kanji and for English, performance on lists comprising visually similar items was overall poorer than for lists of visually distinct items across all serial positions. For mixed lists in which visually similar and visually distinct items alternated through the list, a clear "zig-zag" pattern appeared with better recall of the visually distinct items than for visually similar items. This is the first time that this zig-zag pattern has been shown for manipulations of visual similarity in serial-ordered recall. These data provide new evidence that retaining a sequence of visual codes relies on similar principles to those that govern the retention of a sequence of phonological codes. We further illustrate this by demonstrating that the data patterns can be readily simulated by at least one computational model of serial-ordered recall, the Primacy model (Page and Norris, Psychological Review, 105(4), 761-81, 1998). Together with previous evidence from neuropsychological studies and experimental studies with healthy adults, these results are interpreted as consistent with two domain-specific, limited-capacity, temporary memory systems for phonological material and for visual material, respectively, each of which uses similar processes that have evolved to be optimal for retention of serial order.

The homophone effect in semantic access tasks using kanji words: its relation to the articulatory suppression effect.

The present study examined whether articulatory suppression influences homophone effects in semantic access tasks using Japanese kanji words. In Experiment 1, participants were required to decide whether visually presented word pairs were synonyms. This experiment replicated the homophone effect observed in previous research that showed more false positive errors in response to nonsynonym homophone pairs than to controls. The present study found that this homophone effect was also obtained under an articulatory suppression condition. In Experiment 2, participants performed a semantic decision task, in which they had to judge whether a visually presented target word was an exemplar of a definition that was shown immediately before presentation of the target word. The homophone effect observed in previous studies was replicated--that is, longer response times and more false positive errors were associated with homophones of correct exemplars than with nonhomophone control words. This homophone effect was also obtained under an articulatory suppression conditions. These results suggest that the phonological processing that produces the homophone effects in semantic access tasks using Japanese kanji words does not include articulatory mechanisms.

Semantic involvement in the lexical and sentence processing of Japanese kanji.

This study examined how skilled Japanese readers activate semantic information when reading kanji compound words at both the lexical and sentence levels. Experiment 1 used a lexical decision task for two-kanji compound words and nonwords. When nonwords were composed of kanji that were semantically similar to the kanji of real words, reaction times were longer and error rates were higher than when nonwords had kanji that were not semantically similar. Experiment 2 used a proofreading task (detection of kanji miscombinations) for the same two-kanji compound words and nonwords at the sentence level. In this task, semantically similar nonwords were detected faster than dissimilar nonwords, but error rates were much higher for the semantically similar nonwords. Experiment 3 used a semantic decision task for sentences with the same two-kanji compound words and nonwords. It took longer to detect semantically similar nonwords than dissimilar nonwords. This indicates that semantic involvement in the processing of Japanese kanji produces different effects, depending on whether this processing is done at the lexical or sentence level, which in turn is related to where the reader's attention lies.