Gami-Chunghyuldan ameliorates memory impairment and neurodegeneration induced by intrahippocampal Aβ 1-42 oligomer injection

Soluble oligomeric forms of amyloid beta (AβO) are regarded as a main cause of synaptic and cognitive dysfunction in Alzheimer’s disease (AD) and have been a primary target in the development of drug treatments for AD. The present study utilized a mouse model of AD induced by intrahippocampal injection of AβO (10 μM) to investigate the effects of Gami-Chunghyuldan (GCD), a standardized multi-herbal medicinal formula, on the presentation of memory deficits and neurohistological pathogenesis. GCD (10 and 50 mg/kg/day, 5 days, p.o.) improved AβO-induced memory impairment as well as reduced neuronal cell death, astrogliosis, and microgliosis in the hippocampus. In addition, GCD prevented AβO-triggered synaptic disruption and cholinergic fiber loss. These results suggest that GCD may be useful in the prevention and treatment of AD.     

Un regard structural sur l’inégalité des genres au travail : La causalité des différences « genrées » dans les caractéristiques de réseau de l’employé

This study aims at identifying gender differences in network structure and, hence, at understanding the underlying nature of gender inequalities in organisations. The hypotheses address four ego-network characteristics: network size and density, and ego’s centrality and brokerage. Contrary to the existing body of literature, none significant isolated gender difference in network structure is identified. Instead, those gender differences are triggered exclusively by organisational status, that is to say, they are due to the increased level of power. Thus, organisational status is considered as moderating the relationship between gender and network structure’s characteristics. Some further perspectives are suggested to clarify and generalise the phenomena observed.     

Association between objects and body parts mediated by function

Recent accounts of conceptual knowledge suggest that the specific gestures/actions that should be performed in order to use an object for its intended function are an integral part of its mental representation. If this is true, then the information regarding which body part needs activating to interact with the object should also be part of such representation. Starting from the assumption that not only artefacts (i.e., tools), but also natural objects (i.e., fruits and vegetables) have a function, the present study investigates the existence of a link between a specific object and the effector involved in its use. The Implicit Association Test (IAT) paradigm was adopted to test for an association between natural objects and mouth, and between artefacts and hand (Experiment 1) or foot (Experiment 2). Results showed selective links between objects and effectors, based on which body part is needed to carry out the object's function.     

Posture recognition in Alzheimer's disease

BACKGROUND: Apraxia is neurologically induced deficit in the ability perform purposeful skilled movements. One of the most common forms is ideomotor apraxia (IMA) where spatial and temporal production errors are most prevalent. IMA can be associated Alzheimer's disease (AD), even early in its course, but is often not identified possibly because the evaluation of IMA by inexperienced judges using performance tests is unreliable. The purpose of this study, therefore, is to learn if the Postural Knowledge Test (PKT), a praxis discrimination test that assesses knowledge of transitive (PKT-T subtest) and intransitive (PKT-I subtest) postures and does not require extensive training, is as sensitive and specific as the praxis performance tests. METHODS: We studied 15 subjects with probable AD as well as 18 age-matched controls by having them perform transitive and intransitive gestures to command and imitation, as well as having them discriminate between correct and incorrect transitive and intransitive postures. RESULTS: Overall on all tests, the control subjects performed better than those with AD. In addition all subjects had more trouble with transitive than intransitive gestures. Using a stepwise discriminative analysis, 81.8% of the subjects could be classified according to Group (94.4% of Controls, 66.7% of AD subjects). In this analysis, the PKT-T (transitive posture subtest) was the only measure that contributed to the discrimination of subjects. CONCLUSION: We found that having subjects select the correct transitive hand postures in this "booklet test" was more sensitive than grading their praxis performances even when using judges with extensive training. This suggests that this discrimination test might be an excellent means for diagnosing and screening patients for AD. The reason why recognition of transitive postures is relatively more difficult for our AD subjects is not known. Two possibilities are that the representations for intransitive movements are stronger than those for transitive movements, and hence, more resistant to degradation, or that intransitive acts are stored in parts of the brain not affected by AD.     

Ideational action impairments in Alzheimer's disease

We report data from a group of patients with mild Alzheimer's disease on a range of tasks requiring either stored semantic knowledge about objects (e.g., naming object use) or the execution of action to objects (e.g., miming and using objects). We found that the patients were impaired at miming in response to objects, even when they could describe the object's function. On the other hand, copying gestures was not impaired relative to naming gestures, indicating that an ideomotor deficit in action execution, per se, was unlikely to explain the impairments in object use. We suggest instead that the patients had an impairment in stored motor programmes for action, over and above their deficits in semantic knowledge. Despite this, the patients were better at using than at miming to objects, consistent with the view that proprioceptive input (when using objects) can directly constrain selection of the appropriate motor programme for action.     

Preembryo Personhood: An Assessment of the President’s Council Arguments

The President’s Council on Bioethics has addressed the moral status of human preembryos in its reports on stem cell research and human therapeutic cloning. Although the Council has been criticized for being hand-picked to favor the right-to-life viewpoint concerning human preembryos, it has embraced the idea that the right-to-life position should be defended in secular terms. This is an important feature of the Council’s work, and it demonstrates a recognition of the need for genuine engagement between opposing sides in the debate over stem cell research. To promote this engagement, the Council has stated in secular terms several arguments for the personhood of human preembryos. This essay presents and critiques those arguments, and it concludes that they are unsuccessful. If the best arguments in support of the personhood of human preembryos have been presented by the Council, then there are no reasonable secular arguments in support of that view.     

A stress management programme for Crohn's disease

The present study was designed to assess the effectiveness of techniques of behavioural assessment and treatment of Crohn's disease (CD). On the assumption that stress events have a pronounced influence on the life of Crohn's patients, we proposed stress management treatment. This is intended to control stress and improve patients' personal and social competence. Forty-five patients with Crohn's disease were randomly assigned to one of three treatment groups, two experimental groups: stress management and self-directed stress management, and a control group: conventional medical treatment. The subjects underwent eight individual sessions which were specific to each condition. All subjects completed symptom monitoring diaries. The subjects who received training in stress management experienced a significant post-treatment reduction of tiredness (P < 0.1), constipation (P < 0.1), abdominal pain (P < 0.5) and distended abdomen (P < 0.5). The subjects who received training in self-directed stress management experienced a significant reduction in tiredness (P < 0.1) and abdominal pain (P < 0.5). No significant changes were observed in symptomatology in the conventional medical treatment group. Similar results were obtained in the 12 month follow-up.     

"It's magic!" The effects of presentation modality on children's event memory, suggestibility, and confidence judgments

The current study investigated the influence of presentation modality (live, video, and slide show) on children's memory, suggestibility, recognition, and metamemorial monitoring processes. A total of 270 children in three age groups (5- and 6-year-olds, 7- and 8-year-olds, and 9- and 10-year-olds) watched a magic show and were questioned about it 1 week later. The live show yielded more correct answers to nonleading questions, higher resistance to misleading questions, and better recognition memory than did the video condition, which in turn resulted in better performance than did the slide show. Although presentation modality raised the general level of memory performance, the effects were equally strong in all age groups and did not affect memory phenomena such as the size of the misinformation effect and confidence judgments.     

Inviting witnesses to speculate: effects of age and interaction on children's recall

Inviting speculation has been found to increase children's false recall. In this study, kindergartners and third graders saw a clown perform actions alone or in interaction with a child. Two weeks later, the speculation group recalled all actions and was asked to speculate on half the actions. The control group recalled all actions without speculating. Four weeks after the show, all children recalled all actions again. The speculation group gave more false answers to the speculated items than the control group. Surprisingly, older children tended to report as many if not more false responses than younger children, regardless of speculation. In the speculation group, there were fewer false answers for interactions than actions, but false answers did not differ across observation types in the control group. Finally, speculation did not affect free and cued recall differentially.     

Effects of adding a second reinforcement alternative: implications for Herrnstein's interpretation of r(e)

Herrnstein's hyperbola describes the relation between response rate and reinforcer rate on variable-interval (VI) schedules. According to Herrnstein's (1970) interpretation, the parameter r(e) represents the reinforcer rate extraneous to the alternative to which the equation is fitted (the target alternative). The hyperbola is based on an assumption that extraneous reinforcer rate remains constant with changes in reinforcer rate on the target alternative (the constant-r(e) assumption) and that matching with no bias and perfect sensitivity occurs between response and reinforcer ratios. In the present experiment, 12 rats pressed levers for food on a series of 10 VI schedules arranged on the target alternative. Across conditions, six VI values and extinction were arranged on a second alternative. Reinforcer rate on the second alternative, r2, negatively covaried with reinforcer rate on the target alternative for five of the six VI values on the second alternative, and significant degrees of bias and undermatching occurred in response ratios. Given covariation of reinforcer rate on the second and target alternatives, the constant-r(e) assumption can be maintained only by assuming that reinforcer rate from unmeasured background sources, rb, covaries with reinforcer rate on the second alternative such that their sum, r(e), remains constant. In a single-schedule arrangement, however, r(e) equals rb and thus rb is assumed to remain constant, forcing a conceptual inconsistency between single- and concurrent-schedule arrangements. Furthermore, although an alternative formulation of the hyperbola can account for variations in bias and sensitivity, the modified equation also is based on the constant-r(e) assumption and therefore suffers from the same logical problem as the hyperbola when reinforcer rate on the second alternative covaries with reinforcer rate on the target alternative.