Biomedical subjects

Jun-ichiro Kawahara

Publications and source records attributed to Jun-ichiro Kawahara.

10 recordsLinked to original sources

PubMed2006

The effect of false memory on temporal perception.

This study examined the effect of false memory on temporal perception. The Deese-Roediger-McDermott (DRM) paradigm, which elicits false recognition of a nonpresented word, was used to determine whether the perceived duration of falsely remembered words was longer than that for control words. The study results revealed that the perceived duration for falsely recognized words was longer than that for correctly rejected words. This is the first study to show the effect of false memory on temporal perception and suggests that temporal perception can be affected by conceptual fluency without any perceptual repetition.

Humans↗

PubMed2006

Congruency effect of presentation modality on false recognition of haptic and visual objects.

Studying a list of items related to an item that is not presented (lure item) produces a false memory. We investigated whether a haptic study/test results in false recognition and, if so, whether congruency of presentation modality between study and test reduces the false recognition. After haptic or visual study of lists of real objects that are related to a lure object, participants were asked to recognise whether the objects were presented haptically or visually. We obtained false recognition results with haptic study and/or test. False recognition was reduced when presentation and study modalities were congruent. After haptic study, false recognition was reduced in the haptic test, as compared to the visual test. In contrast, visual study always reduced visual false recognition. These results indicate that there is a general effect of retrieval cues that will reduce false recognition.

Adolescent↗

PubMed2005

The attentional blink is not a unitary phenomenon.

Identification of the second of two targets is impaired if it is presented less than about 500 ms after the first. Three models of this second-target deficit, known as attentional blink (AB), were compared: resource-depletion, bottleneck, and temporary loss of control (TLC). Five experiments, in which three sequential targets were inserted in a stream of distractors, showed that identification accuracy for the leading target depended on an attentional switch whose magnitude varied with distractor-target similarity. In contrast, accuracy for the trailing target depended on similarity between the target and the trailing mask. These results strongly suggest that the AB is not a unitary phenomenon. Resource-depletion was ruled out as a viable account. The effect of attentional switching was handled naturally by the TLC model, while bottleneck models offered the best account of the effect of backward masking.

Attention↗

PubMed2005

Priority information used for the processing of Japanese sentences: thematic roles, case particles or grammatical functions?

The present study investigated scrambling effects on the processing of Japanese sentences and priority information used among thematic roles, case particles and grammatical functions. Reaction times for correct sentence decisions were significantly prolonged for scrambled active sentences with transitive verbs in the first experiment and with ditransitive verbs in the second experiment. Errors were made with scrambled sentences more than canonical sentences in both experiments, which suggested that scrambling effects were apparent in active sentences. Passive sentences in the third experiment indicated that canonical order defined based on case particles, not thematic roles, was more quickly and accurately identified than scrambled order. Potential sentences in the fourth experiment and causative sentences in the fifth experiment indicated that the processing of scrambled sentences based on grammatical functions, but not on case particles, required longer reaction times and resulted in higher error rates than canonical sentences. Consequently, scrambling effects in the present study indicated that neither thematic roles nor case particles can provide fully-satisfactory information for canonical phrase order, and that only grammatical functions offer satisfactory information in all types of sentences.

Cognition↗

PubMed2004

The perceptual and cognitive distractor-previewing effect.

The time it takes to respond to an odd-colored target (e.g., a red diamond among green diamonds) is reduced when distractor-colored items in an appropriate geometric configuration (e.g., multiple red diamonds) are previewed in a preceding trial. B. A. Goolsby and S. Suzuki (2002) suggested that this phenomenon, the distractor-previewing effect, occurs because target saliency is increased by global adaptation to the previewed distractors. The present study tested and extended this idea with visual search experiments using color, face, motion, and word stimuli. We found that the distractor-previewing effect can be obtained with all of these stimuli. In particular, we found that the distractor-previewing effect was elicited by prior activation of distractors by word labels, suggesting a high-level locus for the effect.

Adaptation, Ocular↗

PubMed2004

The attentional blink: resource depletion or temporary loss of control?

Identification of the second of two targets is impaired if it is presented less than about 500 ms after the first. Theoretical accounts of this second-target deficit, known as attentional blink (AB), have relied on some form of limited attentional resource that is allocated to the leading target at the expense of the trailing target. Three experiments in the present study reveal a failure of resource-limitation accounts to explain why the AB is absent when the targets consist of a stream of three items belonging to the same category (e.g., letters or digits). The AB is reinstated, however, if an item from a different category is inserted in the target string. This result, and all major results in the AB literature, is explained by the hypothesis that the AB arises from a temporary loss of control over the prevailing attentional set. This lapse in control renders the observer vulnerable to an exogenously-triggered switch in attentional set.

Analysis of Variance↗

PubMed2004

[Are the visually marked items encoded as a context?].

We examined the attentional constraints of the contextual cueing effect known to occur only for attended items. We focused on whether the items not only attended to but also inhibited afterwards yield the effect or not. We adopted a hybrid paradigm of visual marking and contextual cueing procedures. In the experiment, half the distractors preceded the others and a target for one second. The results showed the contextual cueing effect even with visually marked items. These results suggest that spatial configurations previously attended to and inhibited afterwards can be encoded as visual context.

Attention↗

PubMed2003

The effects of phrase-length order and scrambling in the processing of visually presented Japanese sentences.

The present study investigated the effects of phrase length and scrambling in the processing of Japanese sentences. Reading times of short phrases, long phrases, verbs, and whole sentences, measured by the method of self-paced reading, did not differ in terms of phrase-length order and scrambling. In addition, four types of sentences constructed on the basis of phrase-length order and scrambling did not affect duration times of correctness decision-making for sentences. However, error rates differed between canonical and scrambled sentences regardless of phrase-length order. This result implies that scrambled sentences were harder to judge as correct sentences than canonical sentences. Thus, scrambling affects the appropriate integration of information, whereas phrase-length order is simply an indication of preference and not of cognitive processing. To explain the present result, the authors propose the "configurational structure without movement," which predicts no difference in speed between the processing of canonical and scrambled sentences, apart from error rates.

Adult↗

PubMed2003

Transfer of spatial context from visual to haptic search.

Under incidental learning conditions, spatial layouts can be acquired implicitly and facilitate visual search (contextual-cueing effect). We examined whether the contextual-cueing effect is specific to the visual modality or transfers to the haptic modality. The participants performed 320 (experiment 1) or 192 (experiment 2) visual search trials based on a typical contextual-cueing paradigm, followed by haptic search trials in which half of the trials had layouts used in the previous visual search trials. The visual contextual-cueing effect was obtained in the learning phase. More importantly, the effect was transferred from visual to haptic searches; there was greater facilitation of haptic search trials when the spatial layout was the same as in the previous visual search trials, compared with trials in which the spatial layout differed from those in the visual search. This suggests the commonality of spatial memory to allocate focused attention in both visual and haptic modalities.

Adult↗

PubMed2002

Facilitation of local information processing in the attentional blink as indexed by the shooting line illusion.

Perception of the second of two rapidly sequential targets is impaired if the temporal lag between them is relatively short. This attentional blink (AB) is said to occur because the first target preoccupies attentional resources, leading to a shortage of attention for, and subsequent failure of judgement of, the second target. In the present study, we examined whether the attention which is preoccupied by the first target carries the common characteristic of spatial attention, that is local facilitation of information processing. To index the facilitation, we presented an attention-sensitive probe known as the shooting line illusion in which observers see a progressively drawn line from the attended end to the other. We found that illusory motion was perceived to emanate from the end where the first target was presented. This result demonstrates the inherently spatial nature of attention, even when it is defined by temporal and symbolic variables.

Adult↗