Plasticity of ability to form cross‐modal representations in infant Japanese macaques

In a previous study, Adachi, Kuwahata, Fujita, Tomonaga & Matsuzawa demonstrated that infant Japanese macaques (Macaca fuscata) form cross‐modal representations of conspecifics but not of humans. However, because the subjects in the experiment were raised in a large social group and had considerably less exposure to humans than to conspecifics, it was an open question whether their lack of cross‐modal representation of humans simply reflected their lower levels of exposure to humans or was caused by some innate restrictions on the ability. To answer the question, we used the same procedure but tested infant Japanese macaques with more extensive experience of humans in daily life. Briefly, we presented monkeys with a photograph of either a monkey or a human face on an LCD monitor after playing a vocalization of one of these two species. The subjects looked at the monitor longer when a voice and a face were mismatched than when they were matched, irrespective of whether the preceding vocalization was a monkey's or a human's. This suggests that once monkeys have extensive experience with humans, they will form a cross‐modal representation of humans as well as of conspecifics.     

Relationship of IQ to suicide and homicide rate: an international perspective

IQs were correlated with the z score of suicide rate minus z score of homicide rate using nine regions of the world--established market economies, formerly socialized Europe, India, China, other Asian nations, Sub-Saharan Africa, Latin America/Caribbean, Middle East Crescent, and the USA. Correlations were .85 and .83 with crude rates and age-adjusted rates, respectively. The homicide findings are consistent with previous research in individual countries showing that less intelligent persons commit homicide more often. However, the present findings of a positive correlation between IQ and suicide rates are the opposite of what has been found in the more definitive studies within countries. Explanations for the apparent paradox and for the findings more generally were offered.     

Enhanced recovery of NK cell activity in mice under restraint stress by the administration of a biological response modifier derived from the mycelia of the basidiomycete Tricholoma matsutake

Some types of stressor act on the immune system via the network comprising the endocrine-immune-nervous systems, and are reportedly responsible for the onset of diseases as well as giving impetus to their advance. It is important for the maintenance and promotion of health to cope with stress-induced changes in immunocompetence. Therefore, we studied the effects of administration of a novel biological response modifier (CM6271) derived from the mycelia of the basidiomycete Tricholoma matsutake on the NK cell activity in mice under restraint stress, in order to evaluate its potential to modulate immune responsiveness in stress-loaded individuals. (1) When C57BL/6 mice were restrained in 50-ml tubes for more than 6 h, splenic NK cell activity decreased significantly, but recovered gradually after the mice were released. The extent of the reduction of activity and the degree of recovery depended on the duration of the restraint. (2) The oral administration of CM6271 caused a significant acceleration of the recovery of the activity. This effect was dependent on the timing of administration and the dose given. (3) The administration of CM6271 had no clear effect on the blood levels of ACTH, corticosterone or lipid peroxide levels in the liver. These findings suggest that CM6271 promotes recovery from the decrease in NK cell activity induced by restraint stress.     

Genetic and environmental structure of Cloninger's temperament and character dimensions

The multivariate genetic and environmental structure of Cloninger's Temperament and Character Inventory (TCI) was investigated in a sample of 617 pairs of adolescent and young adult twins from Japan. Additive genetic factors accounted for 22% to 49% of the variability on all TCI temperament scales. Although the theory predicts lower heritability for the character scales, all character subscales had a substantial genetic contribution, and nonshared environmental influences accounted for the remainder. Multivariate genetic analyses showed that several subscales used to define one dimension shared a common genetic basis with subscales defining others. Using the degree of shared genetic influence as the basis to rearrange the TCI subscales into new dimensions, it was possible to create genetically independent scales. The implications for personality measurement, theory, and molecular genetic research are discussed.     

Verb argument information used in a prodrop language: An experimental study in Japanese

Japanese is an SOV, head-final language with phonologically null arguments. Due to these characteristics, any (or all) of the arguments classified by a verb may be null. Consequently, verb argument information which Japanese readers/listeners receive overtly is sometimes incomplete. Furthermore, the arguments in a string may or may not belong to the same clause, and the disambiguating verb argument information does not become available until the end of a clause. These characteristics pose a question of whether or not verb argument information is a useful source of information for on-line syntactic processing in Japanese. An experiment using three types of complex NPs was designed specifically to examine whether Japanese readers use the argument structure information, or alternatively, they simply use minimal attachment in on-line processing of syntactically ambiguous structures. The reading times of three types of complex NPs suggest that native speakers of Japanese indeed utilize verb argument information, and they do so immediately. This finding supports the hypothesis that the Japanese language is processed in the similar way to English in that verb argument information functions as an important source of information in on-line processing. The difference between processing English and processing Japanese is that the former has a mechanism which keeps track of null arguments as well as overt ones.This research was supported in part by a grant to Mineharu Nakayama by the College of Humanitiesm The Ohio State University. A portion of this paper was presented at the CUNY Sentence Processing Conference (1992). I would like to thank Paul G. Gorrell, Julie E. Boland, Laurie A. Stowe, Mineharu Nakayama, and Jerry Packard for their useful comments and discussions.