Biomedical subjects

Hiroshi Toyota

Publications and source records attributed to Hiroshi Toyota.

10 recordsLinked to original sources

PubMed2004

Changes across age groups in self-choice elaboration effects on incidental memory.

The present study investigated age differences in the effects of a self-choice elaboration and an experimenter-provided elaboration on incidental memory. Adults, sixth grade, and second grade subjects chose which of two sentence frames the target fit better in a self-choice elaboration condition. They then judged whether each target made sense in its sentence frame in the experimenter-provided elaboration, then did free recall tests. Only adults recalled better the targets with an image sentence with self-choice elaboration, rather than experimenter-provided elaboration. However, self-choice elaboration was far superior for the recall of targets with nonimage sentences only for second graders. Thus, the effects of self-choice elaboration were determined both by age and by type of sentence frame.

Adult↗

PubMed2004

Self-corrected elaboration effects on incidental memory.

Subjects performed an orienting task involving 3 conditions followed by an unexpected free recall test. The conditions were designed to force 3 types of corrected elaborations: Generated Correction, Chosen Correction, and No Correction. In the Generated Correction condition the subjects were presented with a target word (e.g., Baby) and a bizarre sentence frame (e.g., "____drinks beer.") and asked to correct the target to a congruous word (e.g., Uncle) to make a common sentence. In the Chosen Correction condition, the subjects were presented with a target and its bizarre sentence frame and asked to choose one of the alternative congruous words (e.g., Uncle, Aunt) to make a common sentence. In the No Correction condition, the subjects were presented with a target and its bizarre sentence frame and asked to rate the congruity of each target to its sentence frame. Generated Correction led to a better performance than Chosen Correction and No Correction, but a difference between the last two correction types was not found. These results were interpreted as showing that, by generating correct information, self-corrected elaboration led to facilitation of incidental memory.

Adolescent↗

PubMed2004

Self-generated elaboration and spacing effects on incidental memory.

The purpose of the present study was to investigate the effect of self-generated elaboration on incidental memory as a function of type of presentation (massed vs spacing). Subjects generated answers to "why" questions for target sentences in a self-generated elaboration condition. They then rated the appropriateness of the answers to the questions presented by the experimenter in an experimenter-provided elaboration condition. This procedure was followed by free recall tests. The target sentences were presented twice, in either a massed presentation without intervening items between the first and the second presentation or spaced presentation in which 5 items appeared between the two presentations. The self-generated elaboration effect, namely, higher recall, of self-generated elaboration over experimenter-provided elaboration, occurred with spaced but not with massed presentation. So, self-generated elaboration was facilitated in the spaced presentation because the time between the first and the second presentations led to richer encoding of each target.

Adolescent↗

PubMed2004

Effects of types of elaboration on children's memories of a story: interaction with academic performance.

Two experiments compared the effectiveness of three types of elaboration on incidental and intentional memory for a story: self-generated, self-choice, and experimenter-provided elaboration. In Exp. 1, using the incidental memory paradigm, second graders listened to a fantastic story and then, in the self-generated condition, answered a "why" question about a particular topic in the story. In the self-choice condition, they chose one of the alternative answers to the question and in the experimenter-provided condition, judged the appropriateness of each of two provided answers. This was followed by free-recall and cued-recall tests. Subjects were categorized into two groups, good and poor academic achievers in terms of academic scores in four subject matter areas. For good academic achievers, self-choice elaboration led to a better cued recall than the other two elaboration types. The cued-recall performance of poor achievers was not different with the three conditions. In Exp. 2, using the intentional memory paradigm, the subjects intended to learn a different story and then performed the same procedure as Exp. 1. For poor achievers, self-choice elaboration led to a worse free recall than the other elaboration types, but the free recall of good achievers was not significantly different for the three types of elaboration. The results were interpreted as showing that the effects of self-choice elaboration on incidental and intentional memory were correlated with subjects' academic performance.

Attention↗

PubMed2004

[Paclitaxel, ifosfamide, nedaplatin (TIN) for patients with metastatic urothelial cancer].

TIN (ifosfamide 1.5 g/m2 daily for 3 days, paclitaxel 175 mg/m2, and nedaplatin 70 mg/m2 on day 1) was administered to patients with metastatic urothelial cancer previously treated by platinum-based chemotherapy and repeated every 4 weeks. Four patients received maintenance therapy, which consisted of 5'-DFUR 800 mg/day orally for 12 weeks and 1 subsequent course of TIN. This therapy regimen was repeated for 2 years from initiation of TIN. Eleven of 12 patients (91.6%) demonstrated a major response (3 complete responses, 8 partial responses), with durations of response ranging from 3 to 20 months. Progression-free survival time was from 0 to 20 months (median 8 months). One-year progression-free survival rate was 45.8%. Overall survival time was from 2 to 20 months (median 10.5 months). One-year overall survival rate was 53.5%. Grade 3/4 hematologic toxicity involved neutropenia in 100% and thrombocytopenia in 33.3%. Febrile neutropenia was observed in 5 patients (41.6%). Grade 3 nonhematologic toxicity involved malaise in 15.3%. No patient discontinued this therapy because of complications. TIN is a potent, well-tolerated regimen for previously treated patients with urothelial cancer.

Aged↗

PubMed2003

Changes across age groups in self-choice elaboration and incidental memory.

This study investigated differences in the self-choice elaboration and an experimenter-provided elaboration on incidental memory of 7- to 12-yr.-olds. In a self-choice elaboration condition 34 second and 25 sixth graders were asked to choose one of the two sentence frames into which each target could fit more congruously, whereas in an experimenter-provided elaboration they were asked to judge the congruity of each target to each frame. In free recall, sixth graders recalled targets in bizarre sentence frames better than second graders for self-choice elaboration condition. An age difference was not found for the experimenter-provided elaboration. In cued recall self-choice elaboration led to better performance of sixth graders for recalling targets than an experimenter-provided elaboration in both bizarre and common sentence frames. However, the different types of elaboration did not alter the recall of second graders. These results were interpreted as showing that the effectiveness of a self-choice elaboration depends on the subjects' age and the type of sentence.

Age Factors↗

PubMed2002

Polarization-multiplexed diffractive optical elements fabricated by subwavelength structures.

Polarization-multiplexed phase-only diffractive optical elements with subwavelength structures are proposed and fabricated. The differences among the phase modulations result from the differences among the effective indices exhibited in the subwavelength structures with various filling factors and surface profiles, and the phase retardations are obtained by the relief depth of the structures. The polarization-selective property is achieved by the polarization dependence of the effective indices exhibited in the one-dimensional subwavelength structures and the polarization independence exhibited in the two-dimensional structures. Additionally, the polarization contrast of our polarization-multiplexed elements, defined as the cross talk between the two polarization incidences, is independent of the relief depth. The principle of the polarization multiplexing by use of the subwavelength structures is described, and the fabrication results for the polarization-multiplexed computer-generated holograms are demonstrated.

Journal Article↗

PubMed2002

Behavioral characterization of mice lacking histamine H(3) receptors.

Brain histamine H(3) receptors are predominantly presynaptic and serve an important autoregulatory function for the release of histamine and other neurotransmitters. They have been implicated in a variety of brain functions, including arousal, locomotor activity, thermoregulation, food intake, and memory. The recent cloning of the H(3) receptor in our laboratory has made it possible to create a transgenic line of mice devoid of H(3) receptors. This paper provides the first description of the H(3) receptor-deficient mouse (H(3)(-/-)), including molecular and pharmacologic verification of the receptor deletion as well as phenotypic screens. The H(3)(-/-) mice showed a decrease in overall locomotion, wheel-running behavior, and body temperature during the dark phase but maintained normal circadian rhythmicity. H(3)(-/-) mice were insensitive to the wake-promoting effects of the H(3) receptor antagonist thioperamide. We also observed a slightly decreased stereotypic response to the dopamine releaser, methamphetamine, and an insensitivity to the amnesic effects of the cholinergic receptor antagonist, scopolamine. These data indicate that the H(3) receptor-deficient mouse represents a valuable model for studying histaminergic regulation of a variety of behaviors and neurotransmitter systems, including dopamine and acetylcholine.

Adjuvants, Anesthesia↗

PubMed2002

Guided-mode resonant grating filter with an antireflection structured surface.

We describe a new structure of guided-mode resonant grating (GMRG) filters with low sideband reflectance. This GMRG filter consists of a high-index thin film on an antireflective structured surface called "moth-eye structure." Since the high-index film undulates along the surface structure, the film acts as a modulated optical waveguide. An incident light wave satisfying a resonant condition is reflected by the GMRG filter, and nonresonant light waves pass through the filter. This GMRG filter is valid for reducing reflection of nonresonant light waves in a wide spectral range. The resonant reflection of this new filter was investigated by numerical calculation based on an electromagnetic grating analysis. In the case of a triangular antireflective surface structure whose thickness is 2x greater than its period, the sideband reflectance for nonresonant light waves was lower than 0.5% for TM-polarized light in a wide range of wavelengths.

Journal Article↗

PubMed2002

The bizarreness effect and individual differences in imaging ability.

The bizarreness effect refers to the superior performance in recall of bizarre sentences as compared to common sentences. The subjects studied each target word and in Exp. 1 rated its congruity with its sentence frame. In Exp. 2 they rated the vividness of the image for each sentence frame in which it was included. Four types of sentence frames were provided: bizarre image sentences, bizarre nonimage sentences, common image sentences, and common nonimage sentences. Good imagers and poor imagers were assessed on the Questionnaire Upon Mental Imagery. Both experiments showed that good imagers recalled target words in bizarre image sentences better than target words in common image sentences. A difference between the two sentence types was not observed for poor imagers. The differences between bizarre nonimage sentences and common nonimage sentences were not found for both type of imagers. The results were interpreted as showing that a difference in imaging ability was critical for the occurrence of a bizarreness effect.

Adolescent↗