An fMRI study of temporal sequencing of motor regulation guided by an auditory cue—a comparison with visual guidance

The neuronal system to process and transfer auditory information to the higher motor areas was investigated using fMRI. Two different types of internal modulation of auditory pacing (1 Hz) were combined to design a 2×2 condition experiment, and the activation was compared with that under a visual guidance. The bilateral anterior portion of the BA22 (ant-BA22) and the left BA41/42 were more extensively activated by the combined modulation condition under the auditory cue than that under the visual cue. Among the four auditory conditions with or without the two types of internal modulation, the activation in the ant-BA22 was augmented only on the left side by the combined modulation condition. The left ant-BA22 may be especially involved in integrating the external auditory cue with internal modulation, while the activation on the right side did not depend on the complexity. The role of the left BA41/42 in motor regulation may be more specific to the processing of an auditory cue than that on the right side. These two areas in the left temporal lobe may be organized as a subsystem to handle the timing of complex movements under auditory cues, while the higher motor areas in the frontal lobe support both sensory modalities for the cue. This architecture may be considered as ‘audio-motor control’, which is similar to the visuo-motor control of the front-parietal network.     

Decreased activation in the primary motor cortex area during middle-intensity hand grip exercise to exhaustion in athlete and nonathlete participants

It remains unclear whether activation kinetics in the motor cortex area is affected by training. The purpose of the present study was to examine the effect of training on the motor cortex activation. To accomplish this, the correlation between maximal voluntary contraction and motor cortex (M1) activity was examined. Differences in the motor cortex activation between two groups during exercise were examined in 14 male volunteer participants (M age 25.2 yr., SD = 1.4): seven highly trained athletes (VO2max = 60 ml/kg/min.; maximal voluntary contraction > 55 kg, M MVC = 63.6 kg, SD = 4.2) and seven nonathletes (VO2max < 45 ml/ kg/min.; MVC < 50.0 kg, M MVC = 4 3.5 kg, SD = 5.2). Participants were familiarized with the study protocol during which they performed a maximal voluntary static handgrip test. Specifically, M1 activation was measured by near-infrared spectroscopy throughout a handgrip exercise in which participants performed a sustained middle-intensity handgrip exercise (50% of maximal voluntary contraction) until voluntary exhaustion. In the Athlete group, activation in the M1 at voluntary exhaustion fell below the resting value. In the Nonathlete group, activation in the M1 was elevated throughout the exercise. Results suggest that motor signals from the motor cortex area correlate with exercise training status, especially during fatiguing exercise.     

How does higher in‐group social value lead to positive mental health? An integrated model of in‐group identification and support

Previous research has indicated that the effects of in‐group social value on mental health are mediated by the extent to which individuals identify with their in‐group. Other research has shown that in‐group identification leads to positive mental health because it provides in‐group members with a psychological basis for social support. We examine how the individual's perception of the social value of the in‐group leads to positive mental health, integrating the effects of identification with and support from the in‐group. As predicted, the relationship between higher social value and decreased mental health (e.g. depression, perceived stressful events) is mediated by higher in‐group identification, which in turn leads the members to expect support from the in‐group but not the out‐group. An integrated model of the effects of perceived in‐group social value, identification, and support on mental health is proposed, and the implications are discussed.     

Long-lasting effects of inescapable-predator stress on brain tryptophan metabolism and the behavior of juvenile mice

The kynurenine (KYN) pathway, which is initiated by indoleamine 2,3-dioxygenase, is the main tryptophan (TRP) metabolic pathway. It shares TRP with the serotonin (5-HT) pathway. We investigated the influence of inescapable-predator (rat) stress on behavior and brain TRP metabolism in mice. Male ICR mice (4W) were exposed to 20-min inescapable-predator stress. Behavior on an elevated plus-maze, and TRP, KYN, and 5-HT levels in the prefrontal cortex, hippocampus, amygdala, and dorsal raphe nuclei were measured 1 and 4 weeks after stress exposure. Predator stress increased the number of open-arm entries (NOA) 4 weeks after stress exposure without altering the number of closed-arm entries (NCA). Thus, the open/closed-arm entry ratio (NOA/NCA) increased after stress exposure. Predator stress increased KYN levels in the prefrontal cortex (until 4 weeks after stress exposure) and dorsal raphe nuclei (for 1 week after stress exposure), decreased 5-HT levels in all brain regions (until 4 weeks after stress exposure). Thus, predator stress increased the KYN/5-HT ratio in all regions, in particular in the prefrontal cortex and hippocampus until 4 weeks after stress exposure. Predator stress shifted the balance between the KYN and 5-HT pathways to the KYN pathway, and induced behavioral disinhibition.     

D-cycloserine facilitates procedural learning but not declarative learning in healthy humans: a randomized controlled trial of the effect of D-cycloserine and valproic acid on overnight properties in the performance of non-emotional memory tasks

Although D-cycloserine (DCS), a partial agonist of the N-methyl-d-aspartate (NMDA) receptor, and valproic acid (VPA), a histone deacetylase inhibitor, have been investigated for their roles in the facilitation of emotional learning, the effects on non-emotional declarative and procedural learning have not been clarified. We performed a randomized, blind, placebo-controlled, 4-arm clinical trial to determine the effects of DCS and VPA on the overnight properties of declarative and procedural learning in 60 healthy adults. Subjects were orally administrated a placebo, 100 mg DCS, 400 mg VPA, or a combination of 100 mg DCS and 400 mg VPA before they performed declarative and procedural learning tasks. Subjects then had their performance retested the following day. We observed that DCS facilitated procedural but not declarative learning and that VPA did not contribute to learning. Surprisingly, however, VPA attenuated the enhancement effect of DCS when coadministered with it. These results suggest that DCS acts as an enhancer of hippocampus-independent learning and that VPA may have an extinguishing pharmacological effect on excitatory post-synaptic action potentials that NMDA receptors regulate within procedural learning.     

Effects of intergroup upward comparison, trait self-esteem, and identity shift on state self-esteem and affect in upward comparison with in-group members

The present study investigated factors that protect people low in trait self-esteem (Low-SEs), who may be less skilled at constructing information in self-enhancing manners, from threats after interpersonal upward comparison with in-group members. We hypothesized that even Low-SEs can maintain their state self-esteem under intergroup upward comparison. Furthermore, this study explored the possibility that individuals used identity-shift, a strategy to maintain their personal identity, even in an intergroup upward comparison condition. The results of a quasi-experiment supported these hypotheses. We further explored the possibility that individuals might use a twofold strategy to protect/enhance their self-esteem based on an interplay of personal and social identity.     

Task performance and metacognitive experiences in problem-solving

The effects of task performance on metacognitive experiences and relations between task performance and metacognitive experiences in problem-solving were examined with 69 Japanese undergraduate students. The task was a puzzle called the cross breaker, consisting of seven pieces, and several figures were constructed by using those seven pieces. Eight types of metacognitive experiences, before and after performing the task, were rated. Participants were classified into Success and Failure groups based on their task performance. Use of all but two metacognitive experiences differed between the groups. There were medium to high positive and negative correlations for metacognitive experiences with performance after the puzzle task, whereas metacognitive experiences before the task generally had no significant correlations with performance. Despite small N, participants' metacognitive experiences seemed to reflect their actual performance, suggesting that people obtain information from their performance and use it to revise their metacognitive experiences. Furthermore, metacognitive experiences may help people solve similar problems in the future.     

Perception of emotional tears with body postures,visual scenes,and written scenarios

Emotional tears tend to increase perceived sadness in facial expressions. However, it is unclear whether tears would still be seen as an indicator of sadness when a tearful face is observed in an emotional context (e.g., a touching moment during a wedding ceremony). We examine the influence of context on the sadness enhancement effect of tears in three studies. In Study 1, participants evaluated tearful or tearless expressions presented without body postures, with emotionally neutral postures, or with emotionally congruent postures (i.e., postures indicating the same emotion as the face). The results show that the presence of tears increases the perceived sadness of faces regardless of context. Similar results are found in Studies 2 and 3, which used visual scenes and written scenarios as contexts, respectively. Our findings demonstrate that tears on faces reliably indicate sadness, even in the presence of contextual information that suggests non-sadness emotions.     

Links between real and virtual networks: a comparative study of online communities in Japan and Korea.

The present study explores how online communities affect real-world personal relations based on a cross-cultural survey conducted in Japan and Korea. Findings indicate that the gratifications of online communities moderate the effects of online communities on social participation. Online communities are categorized into a real-group-based community and a virtual-network-based community. The membership of real-group-based online community is positively correlated with social bonding gratification and negatively correlated with information- seeking gratification. Japanese users prefer more virtual-network-based online communities, while their Korean counterparts prefer real-group-based online communities. Korean users are more active in online communities and seek a higher level of socializing gratifications, such as social bonding and making new friends, when compared with their Japanese counterparts. These results indicate that in Korea, personal relations via the online community are closely associated with the real-world personal relations, but this is not the case in Japan. This study suggests that the effects of the Internet are culture-specific and that the online community can serve a different function in different cultural environments.