Recent studies using working memory (WM) span tests have reported that processing activities negatively affected memory performance on the one hand and storage activities adversely affected processing efficiency on the other hand. We examined this processing-storage relationship in two WM span tests that required participants to maintain spatial or verbal memory items while engaging in mental letter rotation, focusing on an interference effect derived from this visuospatial processing task. Results showed that the mental letter rotation task interfered with memory of verbal as well as spatial items, indicating the similarity of these two span tests. Furthermore, the two span tests produced a proportional slowdown in processing speed toward the end of each span list. We discussed possible mechanisms in which the processing and maintenance activities disturb each other from the perspectives of domain-specific representation-based interference and domain-general attentional switching in working memory.

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The purpose of this study was to examine the effect of task experience, long-term dietary restriction and aging on spatial cognition. In experiment 1, nineteen rats were divided into restricted (n = 10) or ad libitum feeding (n = 9) groups at 2.5 months of age, then repeatedly trained in Morris water maze task (reference memory task) and delayed-matching-to-place (DMTP) task (working memory task). Dietary conditions did not affect in performing both tasks. However, deteriorated effect of aging was found in performing DMTP task. These results suggest that repeated task experiences protect rats from age-related reference memory deficits, but not from working memory deficits. Experiment 2 compared the performance of young (n = 8) and aged (n = 4) rats in object exploration task. Young rats reacted to both spatial and nonspatial changes in objects, whereas aged rats reacted only to nonspatial change. Thus, it is suggested that the ability to recognize spatial changes is impaired in aged rats.

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The aim of this study was to determine if flash suppression for contour rivalry consisted of two subsequent stages that might be influenced by the observer's perceptual experience. Participant exposure to primes involved either simultaneous delivery of a grating among orthogonal gratings to both eyes (binocular priming) or to one eye alone (monocular priming) for 1 s. Interstimulus intervals (ISIs) of 0-2000 ms followed the prime, with rival target gratings then simultaneously presented to both eyes for 10-200 ms. When a stimulus-offset asynchrony (SOFFA) of <50 ms was used, the dominant percept to binocular priming was a fusion of the targets. The transfer of the monocular priming suppression to the other eye was found to be difficult. For a SOFFA >50 ms, observers dominantly perceived the unprimed target. With this selective effect, interocular transfer was noted for the monocular priming. When brief targets (10 ms) were employed, two temporal stages with less individuality were detected. When longer targets (200 ms) were used during the monocular priming, the experienced observers were better at preserving the visibility as compared to the naïve observers.

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Recent studies indicate that intentionally suppressing the retrieval of an unwanted memory can impair its later recall. However, it is not clear how long this intentional suppression effect persists. The aim of the current study was to investigate this question using a Think/No-Think paradigm. After participants studied pairs of unrelated words, the cue words from each pair were presented either 0, 4, or 12 times during the Think/No-Think phase of the experiment. Participants were asked to either avoid thinking of the word associated with the cue (Supression condition) or to recall it (Response condition). Participants were then asked to recall the cued words immediately and after a delay of 24 hours. Recall performance in the 12-cue No-Think condition was worse than in the baseline (0) condition, both immediately and 24 hours later. Moreover, the participants who thought about something other than the target during the No-Think trials showed poorer recall than those who did not do so. These results suggest that the effect of intentional suppression that occurs under conditions of self-initiated thought substitution can last for over 24 hours.

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Assuming that the framework in linguistic conceptual combination, such as the head and the modifier of a compound guide the creative process in visual image combination, we focused on the relationship between the constraints of the head or modifier and the emergence of forms and functions of the products. In the experiment, examples of artificial objects and living things were selected as the head and modifier categories that reflect differences in functional constraints. It was treated as artificial object having strong constraints and living things having loose constraints. In this experiment 72 university students were instructed to draw a combination from the two materials presented. The complexity of the form, the novelty of the function and the creativity of the product were assessed. As a result, when artificial objects as heads were combined with living things as modifier, the products displayed a complicated form with a novel function; this combination, therefore, facilitates original and innovative inventions. These findings suggest that the modification of an object with loosed constraints, after establishing the functional significance of the head with strong constraints, is effective and produces inventions.

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Two studies are reported which describe the development and validation of a 20-item measure of self-concept clarity for Hong Kong Chinese adolescents. The ensuing scale is shown to be internally consistent, unidimensional, and relatively free of social desirability bias. As expected, scores of the developed scale varied directly with scores of an indigenous measure of self-esteem and inversely with scores of a measure of social anxiety.

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Two experiments were conducted to investigate the role of the working memory systems in associative learning. Although many previous studies have suggested that the central executive and the visuospatial sketchpad play a crucial role in learning, dual-task methodology was rarely conducted. Experiment 1 demonstrated that spatial tapping was more disruptive than articulatory suppression during an associative learning task. Experiment 2 demonstrated that random letter generation was more disruptive than spatial tapping task and visual noise even though effects of spatial tapping and visual noise were significant. These results suggest that the central executive plays a crucial role in associative learning. Theoretical issues stemming from the findings are discussed in terms of the role of working memory systems in associative process and imagery.

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