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1.
We studied the correlations among sunspot numbers, business cycles, and suicide mortalitites. Based on data from Japan between 1971 and 2001, a significant negative correlation between sunspot numbers and unemployment rate was found, R= -.17. The correlation between suicide mortality and unemployment rate was positive for males (R=.46) and negative for females (R =-.69). Both are statistically significant. The hypothesis that variation of sun activity may affect the economy and the unemployment rate and hence increase the male suicide mortality is raised.  相似文献   
2.
This study investigated the influences of task constraint on motor learning for a trajectory-based movement considering the speed–accuracy relationship. In the experiment, participants practiced trajectory-based movements for five consecutive days. The participants were engaged in training with time-minimization or time-matching constraints. The results demonstrated that the speed–accuracy tradeoff was not apparent or was weak in the training situation. When the participants practiced the movement with a time-minimization constraint, movement errors did not vary, whereas the movement time decreased. With the time-matching constraint, the errors decreased as a session proceeded. These results were discussed in terms of the combination of signal-dependent noises and exploratory search noises. It is suggested that updating spatial and temporal factors does not appear to occur simultaneously in motor learning.  相似文献   
3.
This study investigated the knowledge and strategies used by senior high school students to compare durations of movement by two objects. The developmental process during adolescence was also examined by comparing the results with those published for Grade 7 to Grade 9 students and university undergraduates. A cathode-ray tube monitor was used to present images of two cars traveling in the same direction for various durations and distances. 30 Grade 12 students were asked to identify which of the cars had traveled for a longer duration and why. Analysis suggested that the strategies develop during adolescence in a sequence. Initially, comparison of durations was based on the relative distance traveled by the two cars. Then the comparison was based exclusively on knowledge that "duration = temporal starting point- temporal stopping point." Finally, the two types of knowledge were used appropriately according to the characteristics of the specific task.  相似文献   
4.
present study investigated the effects of two-dimensional arm stiffness and muscle effort required to maintain horizontal arm posture on position-reproduction errors. 12 participants performed a multi-joint position-reproduction task without visual feedback. They were required to indicate a proprioceptively remembered target position with the fingertip of the ipsilateral arm. The results showed that both constant and variable errors were larger in the direction of lower stiffness rather than in the direction of higher stiffness in the stiffness ellipse. In the condition where participants' arm was supported during position perception, variable error was larger than when it was vertically unsupported. These results suggested that proprioceptive accuracy and precision are positively related to the axis length of elliptically represented arm stiffness, and that exerting muscle effort to maintain the arm against the force of gravity may be supportive of human proprioceptive mechanisms.  相似文献   
5.
In appetitive Pavlovian learning, animals learn to associate discrete cues or environmental contexts with rewarding outcomes, and these cues and/or contexts can potentiate an ongoing instrumental response for reward. Although anatomical substrates underlying cued and contextual learning have been proposed, it remains unknown whether specific molecular signaling pathways within the striatum underlie one form of learning or the other. Here, we show that while the striatum-enriched isoform of adenylyl cyclase (AC5) is required for cued appetitive Pavlovian learning, it is not required for contextual appetitive learning. Mice lacking AC5 (AC5KO) could not learn an appetitive Pavlovian learning task in which a discrete signal light predicted reward delivery, yet they could form associations between context and either natural or drug reward, which could in turn elicit Pavlovian approach behavior. However, unlike wild-type (WT) mice, AC5KO mice could not use these Pavlovian conditioned stimuli to potentiate ongoing instrumental behavior in a Pavlovian-to-instrumental transfer paradigm. These data suggest that AC5 is specifically required for learning associations between discrete cues and outcomes in which the temporal relationship between conditioned stimulus (CS) and unconditioned stimulus (US) is essential, while alternative signaling mechanisms may underlie the formation of associations between context and reward. In addition, loss of AC5 compromises the ability of both contextual and discrete cues to modulate instrumental behavior.In Pavlovian learning, animals form associations between discrete or contextual stimuli in their environment to shape their behavior and make appropriate responses. In discrete cue appetitive Pavlovian conditioning, a single cue with a defined onset and offset that typically activates one sensory modality is provided, immediately followed by reward delivery (Hall 2002; Domjan 2006; Ito et al. 2006). Alternatively, behavior can be driven by context, an assortment of stimuli activating a number of sensory modalities that contribute to the representation of environmental space (Balsam 1985; Rudy and Sutherland 1995; Smith and Mizumori 2006). Collectively, these stimuli make up a context that is paired with reward delivery in contextual appetitive learning. One important distinction between these two forms of learning is that in cued conditioning, there is a discrete temporal relationship between conditioned stimulus (CS) and unconditioned stimulus (US). Thus, an animal can effectively anticipate timing of reward delivery from onset and offset of CS. In vivo studies of dopamine (DA) neuron activity have suggested this discrete temporal relationship can be encoded by DA neurons (Schultz et al. 1997; Schultz 1998a). In contrast, in many contextual Pavlovian conditioning tasks, US delivery is not predicted, it is delivered as the animal explores the environment; thus, the temporal relationship between contextual stimuli and reinforcement is not an essential component of the learned associations (Fanselow 2000). These two types of environmental stimuli may be encoded differently and mediated by different neural substrates.Lesion studies have elucidated the anatomical dissociations between cued and contextual appetitive learning. Using a modified Y-maze procedure, it has been suggested that contextual appetitive learning is hippocampus- and nucleus-accumbens (NAc) dependent, while cued learning is dependent on the basolateral nucleus of the amygdala (BLA) and the NAc (Ito et al. 2005, 2006). In addition, as the NAc processes glutamatergic inputs from the amygdala and the hippocampus (Groenewegen et al. 1999; Goto and Grace 2008), recent studies have indicated that disconnecting the hippocampus from the NAc shell can disrupt contextual appetitive conditioning (Ito et al. 2008). In addition to glutamatergic inputs, the NAc, as part of the ventral striatum, receives dense dopaminergic input from midbrain nuclei (Groenewegen et al. 1999). Temporal shifts in phasic DA release in striatal regions has been correlated with appetitive Pavlovian learning (Day et al. 2007), and models of striatal function suggest that DA-dependent modification of glutamatergic transmission in the striatum may underlie reinforcement learning (Reynolds et al. 2001; Reynolds and Wickens 2002).The cAMP pathway has been implicated in plasticity and learning in a number of neuronal structures (Abel et al. 1997; Ferguson and Storm 2004; Pittenger et al. 2006). Adenylyl cyclase (AC), the enzyme that makes cAMP, has nine membrane-bound isoforms, each with different expression patterns and regulatory properties (Hanoune and Defer 2001). AC5 is highly enriched in the striatum, with very low levels of expression in other regions of the brain (Mons et al. 1998; Iwamoto et al. 2003; Kheirbek et al. 2008, 2009), and genetic deletion of AC5 (AC5KO) severely compromises DA''s ability to modulate cAMP levels in the striatum (Iwamoto et al. 2003). Previous studies have shown that AC5KO mice were severely impaired in acquisition of a cued appetitive Pavlovian learning task, while formation of action–outcome contingencies in instrumental learning was intact (Kheirbek et al. 2008). Yet, it remains unknown whether the cAMP pathway in the striatum underlies all forms of appetitive Pavlovian learning, or how it contributes to the ability of Pavlovian cues to modulate instrumental behavior.In this study, we asked if genetic deletion of AC5 selectively impairs cued or contextual appetitive learning. In addition, we tested whether loss of AC5 affects the ability of conditioned cues or contexts to modulate instrumental behavior. Our data indicate that although loss of AC5 abolishes cued appetitive learning, contextual learning is spared. Although contextual stimuli could elicit approach behavior in AC5KO mice, they could not potentiate an ongoing instrumental response, highlighting the importance of this isoform of AC in Pavlovian–instrumental interactions.  相似文献   
6.
A community-based intervention study for suicide prevention was conducted in six towns (total population 43,964) in Akita Prefecture of Japan according to a quasi-experimental design to reduce suicide rates in rural towns. Public awareness raising activities using a health promotion approach emphasizing the empowerment of residents and civic participation were conducted. The welfare measures of promoting a sense of purpose among senior citizens and creating a community network were also taken. As a result, the suicide rate per 100,000 in the intervention towns decreased from 70.8 before intervention (1999) to 34.1 after intervention (2004). The suicide rate per 100,000 in the control towns was 47.8 before intervention and 49.1 after intervention.  相似文献   
7.
The effects of video feedback and nonnegative feedback from other people were examined as possibly ameliorating distorted appraisals of bodily sensations, as well as subjective and physiological anxiety in socially anxious individuals. Nonnegative feedback from a confederate emphasized the absence of negative outcomes (e.g., did not seem to tremble) rather than the presence of positive outcomes (e.g., looked calm). Socially anxious students were randomly assigned to either the experimental group, which received video and social feedback (n=12), or the control group (n 13). Participants were asked to give a videotaped speech twice. After the first speech, the experimental group watched the videotape of their speech and received feedback from a confederate, whereas the control group watched the video of another person's speech. The intervention improved distorted appraisal of bodily sensations and anticipatory anxiety for the experimental group. However, there were no differential effects on anxiety between the groups during speeches.  相似文献   
8.
Relations between duration judgments and verbal or visual working memory, between duration judgments and effect of learning to plan the processing of information about such judgments were investigated. A computer monitor was used to present images of two cars traveling in the same direction for various durations and distances. Participants (N=30) were asked to identify the car that had traveled for the longer duration. Then, participants learned how to solve Piagetian tasks logically. After the learning, they tried to solve the duration judgments task again. Finally, their verbal and visual working memory capacities were assessed. Results indicated the following: (a) numbers of correct answers on the Piagetian tasks were correlated with verbal and visual working memory capacity; (b) the correlations did not significantly decrease after the participants learned how to solve the Piagetian tasks.  相似文献   
9.
Monthly suicide rates in Japan were analyzed for the period from 1976 to 1994 to clarify trends and recurring effects. The data were separated by sex, and the least-squares method was used. The major findings were (1) a significant positive correlation between unemployment rate and suicide rate for both sexes, (2) the suicide rate was highest in April for both sexes, and (3) an upsurge in male suicide mortality was noted from 1983 to 1990. These findings may well be associated with socioeconomic factors as well as neurobehavioral variables.  相似文献   
10.
Long-term recording of activity of the zygomatic muscle, the most important mimic muscle involved in smiling, was performed in 22 disorganized type schizophrenic patients with inappropriate smiles and 15 normal subjects in two separate experiments. During inappropriate smiles, the zygomatic muscle exhibited waxing and waning bursts of activity with an amplitude of 75 to 120 microV, which could not be distinguished from the activity observed during usual smiling in normal subjects. However, the duration of such activity tended to be longer when compared to that in usual smiling by normal subjects as well as by schizophrenic patients. In contrast to usual smiles, inappropriate smiles decreased with personal contact. When asked about their thoughts during smiling shortly after inappropriate smiles, more patients reported that they thought of nothing at all or something not necessarily pleasant rather than something pleasant that would be expected to induce smiling.  相似文献   
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