Word learning does not end at fast-mapping: evolution of verb meanings through reorganization of an entire semantic domain

This paper explores the process through which children sort out the relations among verbs belonging to the same semantic domain. Using a set of Chinese verbs denoting a range of action events that are labeled by carrying or holding in English as a test case, we looked at how Chinese-speaking 3-, 5-, and 7-year-olds and adults apply 13 different verbs to a range of carrying/holding events. We asked how children learning Chinese originally divide and label the semantic space in this domain, how they discover the boundaries between different words, and how the meanings of verbs in the domain as a whole evolve toward the representations of adults. We also addressed the question of what factors make verb meaning acquisition easy or hard. Results showed that the pattern of children’s verb use is largely different from that of adults and that it takes a long time for children to be able to use all verbs in this domain in the way adults do. We also found that children start to use broad-covering and frequent verbs the earliest, but use of these verbs tends to converge on adult use more slowly because children could not use these verbs as adults did until they had identified boundaries between these verbs and other near-synonyms with more specific meanings. This research highlights the importance of systematic investigation of words that belong to the same domain as a whole, examining how word meanings in a domain develop as parts of a connected system, instead of examining each word on its own: learning the meaning of a verb invites restructuring of the meanings of related, neighboring verbs.     

Effects of temporal shapes of sound markers on the perception of interonset time intervals

This study investigated how the temporal characteristics, particularly durations, of sounds affect the perceived duration of very short interonset time intervals (120-360?ms), which is important for rhythm perception in speech and music. In four experiments, the subjective duration of single time intervals marked by two sounds was measured utilizing the method of adjustment, while the markers' durations, amplitude difference (which accompanied the duration change), and sound energy distribution in time were varied. Lengthening the duration of the second marker in the range of 20-100?ms increased the subjective duration of the time interval in a stable manner. Lengthening the first marker tended to increase the subjective duration, but unstably; an opposite effect sometimes appeared for the shortest time interval of 120?ms. The effects of varying the amplitude and the sound energy distribution in time of either marker were very small in the present experimental conditions, thus proving the effects of marker durations per se.     

Serum levels of brain-derived neurotrophic factor (BDNF), BDNF gene Val66Met polymorphism, or plasma catecholamine metabolites, and response to mirtazapine in Japanese patients with major depressive disorder (MDD)

Object We investigated an association between the polymorphism of brain-derived neurotrophic factor (BDNF) gene Val66Met and the response to mirtazapine in Japanese patients with major depressive disorder (MDD). We also examined mirtazapine's effects on the serum BDNF and plasma levels of catecholamine metabolites in these patients. METHODS: Eighty-four patients who met the DSM-IV-TR criteria for MDD were treated with only mirtazapine for 4 weeks. The BDNF Val66Met polymorphism was detected by direct sequencing in the region, and serum BDNF levels and plasma levels of catecholamine metabolites were measured by ELISA and HPLC-ECD, respectively. RESULTS: Mirtazapine treatment for 4 weeks significantly increased serum BDNF levels in the responders, whereas nonresponders showed significant decreases. No association was found between either of the two genotypes (Val/Val vs. Met-carriers) and the response to mirtazapine at T4 or the serum BDNF levels at T0. Mirtazapine did not alter the plasma levels of homovanillic acid (HVA) or 3-methoxy-4-hydroxyphenylglycol (MHPG). Discussion The dynamics of serum BDNF levels, but not plasma levels of HVA and MHPG, reflect the response to mirtazapine treatment; the BDNF Val66Met polymorphism in patients with depression is, however, associated with neither a particular response to mirtazapine treatment nor baseline serum BDNF levels. Conclusion Serum BDNF levels, but not plasma levels of HVA or MHPG, and BDNF Val66Met polymorphism are related to the mirtazapine response in MDD.     

Mental rotation of cubes with a snake face: The role of the human-body analogy revisited

ABSTRACT

Previous research has demonstrated repeatedly that the mental rotation of human-like objects can be performed more quickly than the mental rotation of abstract objects (a body analogy effect). According to existing accounts, the body analogy effect is mediated by projections of one’s own body axes onto objects (spatial embodiment), and the mental emulation of the observed body posture (motoric embodiment). To test whether motoric embodiment facilitates the mental rotation of human-like objects, we conducted an experiment using a snake-like object that had its own body axes but would be difficult to emulate. Twenty-four participants performed the mental rotation of snake-shaped cubes with or without a snake face as well as human-shaped cubes with or without a human face. Results showed that the presence of a face increased mental rotation speeds for both human-shaped and snake-shaped cubes, confirming both the human-body and snake analogy effects. More importantly, the snake analogy effect was equal to the human-body analogy effect. These findings contradict the motoric embodiment account and suggest that any object that can be regarded as a unit facilitates holistic mental rotation, which in turn leads to improved performance.