Emotion, directed forgetting, and source memory

We investigated the role of emotion on item and source memory using the item method of directed forgetting (DF) paradigm. We predicted that emotion would produce source memory impairment because emotion would make it more difficult to distinguish between to-be-remembered (R items) and to-be-forgotten items (F items) by making memory strength of R and F items similar to each other. Participants were presented with negatively arousing, positively arousing, and neutral pictures. After each picture, they received an instruction to remember or forget the picture. At retrieval, participants were asked to recall both R and F items and indicate whether each item was an R or F item. Recall was higher for the negatively arousing than for the positively arousing or neutral pictures. Further, DF occurred for the positively arousing and neutral pictures, whereas DF was not significant for the negatively arousing pictures. More importantly, the negatively arousing pictures, particularly the ones with violent content, showed a higher tendency of producing misattribution errors than the other picture types, supporting the notion that negative emotion may produce source memory impairment, even though it is still not clear whether the impairment occurs at encoding or retrieval.     

State-Supported Science and Imaginary Lock-in: The Case of Regenerative Medicine in Japan

Abstract

Regenerative medicine (RM) in Japan lays strong emphasis on a specific trajectory of its development, which deploys human induced pluripotent stem (iPS) cells as the primary sources for the technology. The technique to create these stem cells was developed in 2006 by a Japanese stem cell scientist, Shinya Yamanaka, and since its applicability to human cells was established about a year later, this new type of cells has become to be considered as a potential substitute for human embryonic stem cells. While the clinical value of these cells are yet to be confirmed, the Japanese Ministry of Education, Culture, Sports, Science and Technology decided to concentrate its support on iPS cells research and turned it into a national project. This decision reflected the state's vision of initiating the transition to a knowledge-based society, which was adopted in the 1990s to tackle the prolonged deflation in the country. As the research became intertwined with this policy vision, however, the Ministry came to see bringing its success as more important than ever, while other trajectories of RM were left underrated and largely unsupported. Industrial actors counteracted this situation and developed an initiative to recognize existing technical capability in the country, but its impact has been so far negligible. This indicates that the nation is locked in the particular trajectory of RM. Hence, this Japanese RM research enterprise presents an interesting case to understand how states' commitment may not only shape the course of scientific research but also reduce flexibility in technological development.     

Age-related trends of interference control in school-age children and young adults in the Stroop color-word test

In this cross-sectional study, differences in interference control, one component of executive function, were investigated among three age groups, 15 early childhood (7- to 8-yr.-olds), 25 middle childhood (9- to 12-yr.-olds), and 20 young adults (21- to 30-yr.-olds). Participants were administered a computer version of the Stroop color-word test with an oral response; correct responses, response time (RT), and the interference ratio were examined. The data indicated that (1) most of the participants showed no errors in word reading, color-naming, and incongruent color-naming tasks; (2) in word-reading and color-naming tasks, RT for 7- to 8-yr.-olds was longer than that for 9- to 12-yr.-olds, while RT of 9- to 12-yr.-olds and young adults were comparable; (3) in an incongruent color-naming task, RT for 7- to 8-yr.-olds was longer than RT for 9- to 12-yr.-olds, which was longer than RT for young adults; and (4) the interference ratio was higher in 7- to 8-yr.-olds than in 9- to 12-yr.-olds, which was higher than in young adults. These results suggested the difference in interference control between early and middle childhood reported on the go/no-go task and the stop-signal procedure would be observed in the Stroop color-word paradigm as well. The utility of this modified Stroop color-word test for those with intellectual and developmental disabilities was discussed.     

Dual-egocentre hypothesis on angular errors in visually directed pointing

We examined the hypothesis that angular errors in visually directed pointing, in which an unseen target is pointed to after its direction has been seen, are attributed to the difference between the locations of the visual and kinesthetic egocentres. Experiment 1 showed that in three of four cases, angular errors in visually directed pointing equaled those in kinesthetically directed pointing, in which a visual target was pointed to after its direction had been felt. Experiment 2 confirmed the results of experiment 1 for the targets at two different egocentric distances. Experiment 3 showed that when the kinesthetic egocentre was used as the reference of direction, angular errors in visually directed pointing equaled those in visually directed reaching, in which an unseen target is reached after its location has been seen. These results suggest that in the visually and the kinesthetically directed pointing, the egocentric directions represented in the visual space are transferred to the kinesthetic space and vice versa.     

Occlusion as a depth cue in the Wheatstone-Panum limiting case

We examined the hypothesis (Ono & Wade, 1985) that occlusion of far stimuli by a near one on the same visual line can operate as a depth cue in stereograms containing different numbers of targets in the two eyes. By controlling eye positions, we created conditions in which the visual system could interpret the retinal images as originating from stimuli on the visual axis of one eye and also created other conditions in which the origin of the retinal images was ambiguous. In Experiment 1, we presented two lines to one eye and a single line to the other eye. When the image of the line on the temporal side of the line pair on one retina fused with the image of the single line on the other retina, the nonfused line appeared farther away more often than it did when the image on the nasal side fused. In Experiment 2, we used two differently shaped stimuli. In the condition in which the nonfused stimulus represented an object being occluded, it appeared farther away more often than in the four conditions in which it did not. In Experiment 3, we extended the idea to three different objects. When the middle of the three images fused with the single image, the nonfused stimulus appeared farther when it could be interpreted as being occluded than when it could not. In the condition in which the most temporal image fused with the single image, the nonfused stimuli appeared farther than in the condition in which the most nasal one fused. The results supported the hypothesis that occlusion plays a role in depth perception in the Wheatstone-Panum limiting case.     

The interaction of perceived distance with the perceived direction of visual motion during movements of the eyes and the head

A horizontally moving target was followed by rotation of the eyes alone or by a lateral movement of the head. These movements resulted in the retinal displacement of a vertically moving target from its perceived path, the amplitude of which was determined by the phase and amplitude of the object motion and of the eye or head movements. In two experiments, we tested the prediction from our model of spatial motion (Swanston, Wade, & Day, 1987) that perceived distance interacts with compensation for head movements, but not with compensation-for eye movements with respect to a stationary head. In both experiments, when the vertically moving target was seen at a distance different from its physical distance, its perceived path was displaced relative to that seen when there was no error in pereived distance, or when it was pursued by eye movements alone. In a third experiment, simultaneous measurements of eye and head position during lateral head movements showed that errors in fixation were not sufficient to require modification of the retinal paths determined by the geometry of the observation conditions in Experiments 1 and 2.     

A quantitative near-infrared spectroscopy study: a decrease in cerebral hemoglobin oxygenation in Alzheimer's disease and mild cognitive impairment

A newly developed quantitative near-infrared spectroscopy (NIRS) system was used to measure changes in cortical hemoglobin oxygenation during the Verbal Fluency Task in 32 healthy controls, 15 subjects with mild cognitive impairment (MCI), and 15 patients with Alzheimer's disease (AD). The amplitude of changes in the waveform, which was quantitatively calculated by a signal processing method, was significantly lower in the frontal, and the bilateral parietal areas in the AD group, whereas that in the MCI group was significantly lower only in the right parietal area. The NIRS system may be a potential tool for the primary screening of AD.     

Remembering a nuclear accident in Japan: did it trigger flashbulb memories?

Flashbulb memories are vivid memories of the details surrounding the discovery of an emotional event. We investigated whether the nuclear accident that occurred in Japan in 1999 produced flashbulb memories among people who lived near the accident site. A questionnaire was distributed twice (approximately 3 weeks after the accident and 1 year later) to (1) the residents of the communities surrounding the accident site, (2) the students at a university near the accident site, and (3) the students at two universities far away from the accident site. Flashbulb memory holders were defined as those individuals who showed consistent memories between test and retest. The results indicated that only a small percentage of participants formed flashbulb memories. Further, no age-related decline was found. Flashbulb memories were distinguished by perfect or near perfect scores on four attributes: source, place, activity, and people. The results also indicated that the ratings on emotional reactions, personal consequentiality, and surprise did not differentiate between the flashbulb and non-flashbulb memory holders. In contrast, the flashbulb memory holders reported rehearsing more than the non-flashbulb memory holders. These results supported the notion that flashbulb memories are formed through rehearsal rather than at encoding. However, it is also possible that rehearsal was a result of the flashbulb memory.     

Weaning in Japan: A longitudinal study of mother and child behaviours during milk- and solid-feeding

Behaviours of seven Japanese mother-infant dyads during daytime feeding of both milk and solids were observed longitudinally to the middle of the second year. The first 3 months were a period of exclusive milk-feeding largely uninterrupted by mother-infant social interaction. In the following 6 months there was increasing mother-infant communicative interaction during milk-feeding and the mother began attempts to feed solids. After 8 months, weaning was promoted by reduction in some types of interaction during milk-feeding, and increased rejection by the infant of passive feeding as self-feeding of solids increased. Self-feeding was at first mainly by hand, and later with tools. A positive correlation was found between hand-feeding at 12-14 months and active physical stimulation of the infant by the mother during milk-feeding in the first year. Self-feeding of solids with tools increased significantly after 1 1/2 years, and the mother supported this development. The mother showed non-intentional eating-like mouth movement at the moment infants ate (empathetic behaviour), and this behaviour peaked in the latter half of the first year and decreased thereafter. The development of independence or autonomy in feeding was a mutual or cooperative process between mother and infant, and was initiated by the infant rather than imposed by the mother.