Bilateral lesions of the insular cortex or of the prefrontal cortex block the association between taste and odor in the rat

The neural basis for the association between taste and odor was investigated in the rat. First, behavioral procedures to study the mechanisms underlying the association between qualitative aspects of the odor and taste in rats were developed. Rats were presented with several pairings of the 0.3 mol/L NaCl solution and a flavor, and pairings of distilled water and another flavor. Then the rats received an IP injection of a furosemide to develop sodium deficiency. On the next day, the rats were presented with either of two types of odor-flavored water: water in which the flavor had been paired with NaCl, or water in which the flavor (grape or coffee) had been paired with distilled water. Normal rats avoided ingesting the water flavored with the odor previously paired with NaCl. Sodium-deprived rats, however, ingested the water flavored with that odor. Rats with lesions in either the insular cortex or in the prefrontal cortex neither preferred nor avoided the water flavored with the odor paired with NaCl. It was concluded that rats acquire association between taste and odor, and that the insular and the prefrontal cortices of the rats were involved in this association.     

The effects of phrase-length order and scrambling in the processing of visually presented Japanese sentences

The present study investigated the effects of phrase length and scrambling in the processing of Japanese sentences. Reading times of short phrases, long phrases, verbs, and whole sentences, measured by the method of self-paced reading, did not differ in terms of phrase-length order and scrambling. In addition, four types of sentences constructed on the basis of phrase-length order and scrambling did not affect duration times of correctness decision-making for sentences. However, error rates differed between canonical and scrambled sentences regardless of phrase-length order. This result implies that scrambled sentences were harder to judge as correct sentences than canonical sentences. Thus, scrambling affects the appropriate integration of information, whereas phrase-length order is simply an indication of preference and not of cognitive processing. To explain the present result, the authors propose the configurational structure without movement, which predicts no difference in speed between the processing of canonical and scrambled sentences, apart from error rates.     

Intracerebroventricular Administration of Mineralocorticoid Receptor Antisense Oligonucleotides Attenuates Salt Appetite in the Rat

The anterior ventral third ventricle (AV3V) region of the brain contains high concentrations of mineralocorticoid receptors (MR) and glucocorticoid receptors (GR) that are important in the maintenance of body fluid and electrolyte balance as well as other physiological processes. Daily intracerebroventricular pulse injections of MR antisense oligonucleotides significantly suppressed deoxycorticosterone acetate (DOCA) induced salt appetite in a dose-related manner. Similar administration of GR antisense or scrambled/sense oligonucleotide into the third ventricle failed to inhibit salt appetite. Salt appetite aroused after adrenalectomy was not suppressed by MR antisense oligonucleotide treatments but was suppressed by an antisense oligonucleotide directed against the angiotensin II AT1 receptor subtype. Receptor binding analysis demonstrated that MR and GR oligonucleotide treatments each reduced their respective receptor subtypes. Finally, although GR antisense oligonucleotide treatment was ineffective in suppressing DOCA-induced salt appetite, this treatment did increase stress induced corticosterone release as well as delayed the recovery of corticosterone to basal levels after stress.     

After-effects induced by interactions between hydrogen and the martensite transformation in Ni–Ti superelastic alloy

The effects of dynamic interactions between hydrogen and a stress-induced martensite transformation on the recovery of deteriorated tensile properties by ageing in air at room temperature have been investigated for a Ni–Ti superelastic alloy. A specimen is subjected to single stress-induced martensite and reverse transformations immediately after hydrogen charging. Upon tensile testing, brittle fracture occurs in the latter half of the elastic deformation region of the martensite phase after the stress-induced martensite transformation. Upon ageing before the tensile test, fracture occurs during the stress-induced martensite transformation. In addition, the nano- and micro-morphologies of the brittle outer part of the fracture surface of the specimen are changed by ageing. Thus, the tensile properties markedly deteriorate, rather than recover, by ageing. The present results clearly indicate that dynamic interactions between hydrogen and the stress-induced martensite transformation have serious after-effects on hydrogen embrittlement of Ni–Ti superelastic alloy.     

Syntax in a native language still continues to develop in adults: honorification judgment in Japanese

Native languages (L1s) are tacitly assumed to be complete and stable in adults. Here we report an unexpected individual variation in judgment of L1 regarding Japanese sentences including honorification, and further clarify its neural basis with functional magnetic resonance imaging (fMRI). By contrasting an honorification judgment task with a spelling judgment task, the lower performance group showed more extensive activation in the left inferior frontal gyrus than did the higher performance group. Moreover, activation in the left dorsal and ventral triangular parts negatively correlated with the performance of the honorification judgment task. This modulation pattern demonstrates that cortical activations recruited for sentence processing depend on individual performances even in L1.     

The relationship between three types of aggression and peer relations in elementary school children

Previous studies have repeatedly found that aggression causes various internalizing and externalizing problems. Despite the robust relationship, exactly how aggression causes these problems remains unclear, although it is plausible to postulate that this occurs both directly and indirectly (via other behavioural factors). One possible indirect factor might be the aggravation of peer relations. The poor peer relations of aggressive children could make them isolated psychologically or physically from peers, which in turn might result in depressive or disruptive problems. This study examined the relationships between three types of aggression and peer relations in Japanese elementary school children. The three aggression types comprised reactive-expressive (i.e., verbal and physical aggression), reactive-inexpressive (e.g., hostility), and proactive-relational aggression (i.e., aggression that can break human relationships, for instance, by circulating malicious rumours). Participants were 1581 children in grades 4 to 6 (752 boys and 829 girls), all of whom completed the Proactive-Reactive Aggression Questionnaire for Children to measure three types of aggression and the Peer Relation Questionnaire to measure peer relations (mutual understanding, self-disclosure, and similarity of taste) and number of friends. Hierarchical regression analyses of the data showed that higher scores of relational aggression were significantly associated with higher scores of all of the peer relations and the number of friends, and that higher scores of inexpressive aggression were significantly associated with lower scores of all except for self-disclosure in the peer relations. These findings suggest that among the three types of aggression, relational aggression leads to the best friendship in both dyadic relations and the number of friends, whereas inexpressive aggression to the poorest friendship. The implications of these findings with respect to internalizing and externalizing problem behaviours for aggressive children are discussed.     

Temporal cortex activation during speech recognition: an optical topography study

Cortical activity during speech recognition was examined using optical topography (OT), a recently developed non-invasive technique. To assess relative changes in hemoglobin oxygenation, local changes in near-infrared light absorption were measured simultaneously from 44 points in both hemispheres. A dichotic listening paradigm was used in this experiment, in which target stimuli and non-target stimuli were presented to different ears. Subjects were asked to track targets and to press a button when targets shifted from one ear to the other. We compared three tasks: (i) a control task, in which a tone was used as the target; (ii) a repeat task, in which the target was one repeated sentence; (iii) a story task, in which the targets were continuous sentences of a story. The activity for the story task, compared with the repeat task, was localized in the left superior temporal cortex. Relative to the control task, we observed in this region a larger increase in oxyhemoglobin concentration and a decrease in deoxyhemoglobin concentration in the story task than those in the repeat task. These results suggest that the activity in the left temporal association area reflects the load of auditory, memory, and language information processing.     

First interactions between hydrogen and stress-induced reverse transformation of Ni–Ti superelastic alloy

The first dynamic interactions between hydrogen and the stress-induced reverse transformation have been investigated by performing an unloading test on a Ni–Ti superelastic alloy subjected to hydrogen charging under a constant applied strain in the elastic deformation region of the martensite phase. Upon unloading the specimen, charged with a small amount of hydrogen, no change in the behaviour of the stress-induced reverse transformation is observed in the stress-strain curve, although the behaviour of the stress-induced martensite transformation changes. With increasing amount of hydrogen charging, the critical stress for the reverse transformation markedly decreases. Eventually, for a larger amount of hydrogen charging, the reverse transformation does not occur, i.e. there is no recovery of the superelastic strain. The residual martensite phase on the side surface of the unloaded specimen is confirmed by X-ray diffraction. Upon training before the unloading test, the properties of the reverse transformation slightly recover after ageing in air at room temperature. The present study indicates that to change the behaviour of the reverse transformation a larger amount of hydrogen than that for the martensite transformation is necessary. In addition, it is likely that a substantial amount of hydrogen in solid solution more strongly suppresses the reverse transformation than hydrogen trapped at defects, thereby stabilising the martensite phase.     

An intervention study of the effects of the coping strategy of "finding positive meaning" on positive affect and health

Previous research has shown that positive affect (PA) is associated with the coping strategies of "searching for and finding positive meaning." The purpose of this study was to investigate the relationship between the coping strategy of "finding positive meaning" and PA using an intervention method. Additionally, inasmuch as previous research has revealed that PA is associated with physical and mental health status, the current study measured health status in order to carry out a preliminary test as to whether PA increased by the intervention can also improve health. Participants in the intervention group (Japanese graduate students; 13 men and 16 women) reported the most stressful event during the past 3 days and its positive meaning, while those in the control group (13 men and 15 women) reported the most stressful event alone. Both groups reported twice a week for 5 successive weeks using e-mails. Three questionnaires, the Japanese version of the Positive and Negative Affect Schedule scales for measuring positive and negative affects (NA), the situational version of the General Coping Questionnaire for coping strategies, and the Japanese version of the General Health Questionnaire for health status, were administered to all participants just before the start of the intervention, after the conclusion of the intervention, and at the 5-week follow-up session. Results revealed that the "finding positive meaning" coping strategy and PA were enhanced by the intervention in the follow-up for men and women with no changes in NA. For the health scales of the General Health Questionnaire, no significant group-related effects were observed. Thus, the intervention had no significant influence on NA or health status. Implications of these findings for future research are discussed along with a few limitations in this study.