Watch what you type: The role of visual feedback from the screen and hands in skilled typewriting

Attention, Perception, & Psychophysics - Skilled typing is controlled by two hierarchically structured processing loops (Logan & Crump, 2011): The outer loop, which produces words,...     

Perceptual transparency in 3- to 4-month-old infants

We examined perceptual transparency in infants. In a previous study, Johnson and Aslin (2000 Developmental Psychology 36 808 - 816) found that 4-month-olds could perceive transparency in a moving chromatic display, but not in an achromatic display. In this study, we further examined perceptual transparency in infants using a static achromatic display. Considering the development of figural organisation and contrast sensitivity, we assumed that 3- to 4-month-olds would perceive transparency even in a static achromatic display. We created a transparency and a non-transparent display composed of a partially overlapping circle and square, by switching the colours. Infants aged 3 to 4 months (n = 24) were familiarised with the transparency display (experiment 1) or with the non-transparent display (experiment 2). Then, they were confronted with a uniform colour and a two-colour figure. Infants showed novelty preference for the two-colour figure after they had been familiarised with the transparency display (experiment 1), but not after they had been familiarised with the non-transparent display (experiment 2). These results suggest that 3- to 4-month-old infants can perceive transparency in a static achromatic display.     

Anisotropic motion coherence sensitivities to expansion/contraction motion in early infancy

We investigated 2- and 3-month-olds' motion coherence sensitivities to radial expansion/contraction by using the preferential looking method. The infants were tested with a stimulus composed of two dynamic random dot patterns placed side by side: an expansion (or a contraction) pattern and a random directional pattern. The results showed that the 3-month-old infants tested with both a contraction and random directional pattern could discriminate between those two motions significantly, even when the contraction motion coherence was relatively low (50%). On the other hand, the 3-month-old infants who were tested with both expansion and random directional pattern could not discriminate between those two motions. None of the 2-month-old infants showed significant discrimination between the expansion/contraction and random motion patterns. Results of the present study suggest that anisotropic motion coherence sensitivities to radial expansion/contraction emerge at around 3 months of age.     

Orthogonality is not a panacea: backpropagation and "catastrophic interference"

Connectionist models with the backpropagation learning rule are said to exhibit catastrophic interference (or forgetting) with sequential training. Subsequent works showed that interference can be reduced by using orthogonal inputs. This study investigated, with a more rigorous assessment method, whether all orthogonal inputs lead to comparable extent of interference using three coding schemes. The results revealed large differences between the coding schemes. With larger networks, dense inputs led to severer interference compared with sparse inputs. With smaller networks, all the three schemes led to comparable extent of interference. Therefore, this study proved that not all the orthogonal inputs cause the same extent of interference, and that severity of interference depends on the interaction of the input coding scheme and the network size.     

Children's Other-Oriented Behaviors in Distress Situations

Children’s other-oriented behaviors in distress situations, when observed, appear to be different depending on the kind of distress situations. The authors investigated developmental differences in children’s other-oriented behaviors by comparing two distress situations: participant-caused/other-victim and other-caused/participant-victim situations. The kinds of other-oriented behaviors younger and older children engaged in were observed under an experimental setting—two tasks that involved accidentally collapsing the object the other constructed. The results showed that other-oriented behaviors were observed irrespective of age and situations. However, the developmental changes of these behaviors were different between the two situations: Older children showed more kinds of other-oriented behaviors than younger children did in the participant-caused situation, whereas no differences between ages were observed in the participant-victim situation. Other-oriented behaviors toward the victim when the participants were at fault appeared to develop during the preschool years, whereas other-oriented behaviors toward those responsible for participants’ distress appeared to be difficult for preschoolers. The developmental origin of and changes in other-oriented behaviors in cases when children are victims should be further investigated, in additional age groups, as should the influence of cultural context.     

Discordance in Recovery Between Altered Locomotion and Muscle Atrophy Induced by Simulated Microgravity in Rats

Exposure to a microgravity environment leads to adverse effects in motion and musculoskeletal properties. However, few studies have investigated the recovery of altered locomotion and muscle atrophy simultaneously. The authors investigated altered locomotion in rats submitted to simulated microgravity by hindlimb unloading for 2 weeks. Motion deficits were characterized by hyperextension of the knees and ankle joints and forward-shifted limb motion. Furthermore, these locomotor deficits did not revert to their original form after a 2-week recovery period, although muscle atrophy in the hindlimbs had recovered, implying discordance in recovery between altered locomotion and muscle atrophy, and that other factors such as neural drives might control behavioral adaptations to microgravity.     

Infants’ perception of curved illusory contour with motion

Recently, Masuda et al. (submitted for publication) showed that adults perceive moving rigid or nonrigid motion from illusory contour with neon color spreading in which the inducer has pendular motion with or without phase difference. In Experiment 1, we used the preferential looking method to investigate whether 3–8-month-old infants can discriminate illusory and non-illusory contour figures, and found that the 7–8-month-old, but not the 3–6-month-old, infants showed significant preference for illusory contour with phase difference. In Experiment 2, we tested the validity of the visual stimuli in the present study, and whether infants could detect illusory contour from the current neon color spreading figures. The results showed that all infants might detect illusory contour figure with neon color spreading figures. The results of Experiments 1 and 2 suggest that 7–8-month-old infants potentially perceive illusory contour from the visual stimulus with phase-different movement of inducers, which elicits the perception of nonrigid dynamic subjective contour in adults.     

Intergroup retaliation and intra‐group praise gain: The effect of expected cooperation from the in‐group on intergroup vicarious retribution

Intergroup vicarious retribution is the phenomenon whereby, after an out‐group member attacks an in‐group member, a member of the victim's group retaliates against a member of the perpetrator's group. This study examined the effect of expected cooperation from the in‐group on intergroup vicarious retribution through intra‐group reputation based on praise gain and exclusion avoidance. In the experiment, we conducted a one‐on‐one match in which, after participants learned that an out‐group member (as the winner) had imposed a fine on an in‐group member (as the loser) in a previous round, winning participants were allowed to impose an arbitrary fine on the other losing out‐group member. As a result, participants imposed a larger fine on their out‐group member opponent in retaliation when they were expected by in‐group members to cooperate than when such cooperation was not expected. Furthermore, participants regarded a fine as intra‐group cooperation. Since a path analysis revealed a mediating effect of praise gain, but no mediating effect of exclusion avoidance, expected cooperation from in‐group members facilitated vicarious retribution because those involved in retribution sought praise from other in‐group members. These findings suggest that the intra‐group reputation dynamics of expected cooperation and praise gain escalate intergroup conflict.     

The Simon task with multi-component responses: two loci of response–effect compatibility

The stimulus–response compatibility (SRC) effect refers to the phenomenon that responses are faster and more accurate when stimulus and response correspond than when they do not. The phenomenon is robust in that it is observed even when SRC is irrelevant to performing the task, a variant known as the Simon effect. Recent studies also demonstrated that responses are faster when they are spatially compatible with their effects in the environment (action effects) than when they are incompatible. This response–effect (R–E) compatibility effect is thought to stem from the fact that stimuli first activate anticipated effect codes, which then activate corresponding action codes. In the present study, the Simon task was used to examine influences of multiple response components on performance. Three response components were orthogonally manipulated. The results of three experiments indicated that there are two separate processes that are influenced by R–E compatibility; one that is responsible for the SRC effect (S–R translation) and the other that is independent of SRC (action programming). The influence of R–E compatibility on the former process depended on manipulations that varied attentional demands of the task.     

Influences of response position and hand posture on the orthogonal Simon effect

When lateralized responses are made to the locations of vertically arrayed stimuli, two types of mapping effect have been reported: an overall up-right/down-left advantage and mapping preferences that vary with response position. According to Cho and Proctor's (2003) multiple asymmetric codes account, these orthogonal stimulus-response compatibility effects are due to the correspondence of stimulus polarity and response polarity, as determined by the positions relative to multiple frames of reference. The present study examined these two types of orthogonal compatibility for situations in which participants made left-right responses to the colours of a vertically arrayed stimulus set, and stimulus location was irrelevant. Although a significant orthogonal Simon effect was not evident when responding at a centred, neutral response position, the effect was modulated by response eccentricity (Experiment 2) and hand posture (Experiment 3). These effects are qualitatively similar to those obtained when stimulus location is task relevant. The results imply that, as Proctor and Cho's (2006) polarity correspondence principle suggests, the stimulus polarity code activates the response code of corresponding polarity even when stimulus location is irrelevant to the task.