Deficits of spatial and non-spatial memory and of auditory fear conditioning following anterior thalamic lesions in mice: comparison with chronic alcohol consumption

This study was aimed at determining (i) whether or not bilateral subtotal lesions of the anterior thalamic nuclei (ATH) in rodents produced memory deficits for spatial and/or non-spatial information and of auditory fear conditioning, and (ii) if these eventual deficits resemble those produced by chronic alcohol consumption (CAC). Working memory was assessed using both spatial (spontaneous alternation) and non-spatial (temporal alternation) delayed response tasks. Results showed that ATH lesions induced delay-dependent memory impairments in both spatial and non-spatial alternation tasks, as well as a decreased level of auditory and background contextual fear conditioning compared with respective controls. CAC did not induce accelerated rate of forgetting in the spatial and non-spatial tasks, but increased the vulnerability to interference in the spatial task. CAC impaired only background contextual fear conditioning. We conclude that ATH nuclei are involved in the maintenance of information over time, regardless of the nature (spatial vs. non-spatial) of the information, and play a role in associative processes for both unimodal (the tone) and polymodal (contextual) information. In contrast, ATH dysfunction does not account for the memory disorders induced by the CAC treatment. Our results contribute to showing that the functional overlap between the structures comprising the hippocampo-mamillo-thalamic pathway is only partial.     

Oxytocin induces preservation of social recognition in male rats by activating alpha-adrenoceptors of the olfactory bulb

In this report, a series of four experiments was performed to evaluate the relationship between the olfactory bulb norepinephrine system and intra-olfactory bulb infusion of oxytocin in the preservation of social memory responses. The present data indicate that oxytocin exerts this preservation of social recognition through a specific, receptor-mediated mechanism within the olfactory bulb (experiment 1). The involvement of the olfactory bulb norepinephrine system is revealed by the demonstration that retrodialysis of oxytocin into the olfactory bulb increases norepinephrine release (experiment 4). Our data suggest that the increased output of olfactory bulb norepinephrine resulting from oxytocin appears to activate alpha-adrenoceptors to produce this preservation in recognition because infusions of clonidine into the olfactory bulb preserve recognition responses in a manner similar to that observed with oxytocin (experiment 2). In addition, a co-infusion of oxytocin with phentolamine abolishes recognition responses (experiment 3). Accordingly, this model affords the opportunity to study neuropeptide-catecholamine interactions, link these interactions with a specific behavioural outcome and identify a novel function/site of action for oxytocin in the male.     

Combined lesions of cholinergic and serotonergic neurons in the rat brain using 192 IgG-saporin and 5,7-dihydroxytryptamine: neurochemical and behavioural characterization

This study assessed behavioural and neurochemical effects of i.c.v. injections of both the cholinergic toxin 192 IgG-saporin (2 microgram) and the serotonergic toxin 5,7-dihydroxytryptamine (5,7-DHT; 150 microgram) in Long-Evans female rats. Dependent behavioural variables were locomotor activity, forced T-maze alternation, beam walking, Morris water-maze (working and reference memory) and radial-maze performances. After killing by microwave irradiation, the concentrations of acetylcholine, monoamines and 5-hydroxyindoleacetic acid (5-HIAA) were measured in the hippocampus, frontoparietal cortex and striatum. 192 IgG-saporin reduced the concentration of acetylcholine by approximately 40% in the frontoparietal cortex and hippocampus, but had no effect in the striatum. 5,7-DHT lesions reduced the concentration of serotonin by 60% in the frontoparietal cortex and 80% in the hippocampus and striatum. Noradrenaline was unchanged in all structures except the ventral hippocampus where it was slightly increased in rats given 192 IgG-saporin. Cholinergic lesions induced severe motor deficits but had no other effect. Serotonergic lesions produced diurnal and nocturnal hyperactivity but had no other effect. Rats with combined lesions were more active than those with only serotonergic lesions, showed motor dysfunctions similar to those found in rats with cholinergic lesions alone, and exhibited impaired performances in the T-maze alternation test, the water-maze working memory test and the radial-maze. Taken together and although cholinergic lesions were not maximal, these data show that 192 IgG-saporin and 5,7-DHT lesions can be combined to selectively damage cholinergic and serotonergic neurons, and confirm that cholinergic-serotonergic interactions play an important role in some aspects of memory, particularly in spatial working memory.     

Cortical activation during retrieval of arithmetical facts and actual calculation: a functional magnetic resonance imaging study

By using functional magnetic resonance imaging (fMRI), the neural substrates involved in mental recitation of the single-digit multiplication table and serial subtraction were studied. The former depends mostly on well-learned arithmetical facts, while the latter requires arithmetic processing. Activation during each task was compared with that in a number counting control. During the recitation of single-digit multiplication, the activated regions included the area lying along the left intraparietal sulcus, the premotor and supplementary motor areas, and the posterior portion of the left inferior frontal gyrus. The areas activated during serial subtraction included these areas as well as the bilateral prefrontal and right parietal areas. From the results obtained during retrieval of the multiplication table in this study and previous studies, it was concluded that semantic memory of the multiplication table is stored in the area lying along the intraparietal sulcus and that the frontal areas play an executive role in utilizing the semantic memory of arithmetical facts. It was assumed that the arithmetical facts requiring actual calculation are also stored in the same region. The additional activation during serial subtraction compared with the activation during retrieval of the multiplication table is probably due to the processes of actual calculation. These processes include proper alignment of digits, which may have caused the right parietal activation, and maintaining digits needed for the mental serial subtractions, which may have caused the bilateral prefrontal activation.     

Facilitating effect of histamine on spatial memory deficits induced by dizocilpine as evaluated by 8-arm radial maze in SD rats

AIM: To investigate whether or not histamine is involved in spatial memory deficits induced by dizocilpine (MK-801) as evaluated by 8-arm radial maze of rats. METHODS: 8-Arm (4-arm baited) radial maze was used to measure spatial memory in rats. RESULTS: Bilaterally intrahippocampal (ih) injection of MK-801 (0.3 μg/site) impaired working memory and reference memory in rats. Both histamine (50, 100 ng/site, ih) and intraperitoneal (ip) injection of histidine (100, 200 mg/kg) markedly improved the spatial memory deficits induced by MK-801. On the other hand, the ameliorating effect of histidine (100 mg/kg, ip) was completely antagonized by α-fluoromethylhistidine (α-FMH, 5 μg/site, ih), a potent and selective histidine decarboxylase (HDC) inhibitor, and H_1-antagonist pyrilamine (1 μg/site, ih), but not by H_2-antagonist cimetidine, even at a high dose (2.5 μg/site, ih). CONCLUSION: The hippocampal histamine plays an important role in the ameliorating effect on MK-801-induced spatial memory deficits,     

生命1号健脑强身及促骨生长的实验研究

采用水迷宫法、穿梭箱法、避暗法、跳台法观察了生命1号对小鼠学习、记忆、巩固的影响。灌胃给生命1号可改善东莨菪碱、樟柳碱致小鼠记忆获得障碍。生命1号能明显提高单核细胞吞噬功能，显著增加小鼠血清溶血素的含量，促进T淋巴细胞的转化。除此之外，还能明显地增加阳虚大鼠股骨的重量、长度、直径及皮质厚度；提高血清钙、磷水平；降低血清碱性磷酸酶的含量，具有促进骨骼生长的作用。     

Familiar Face and Voice Matching and Recognition in Children with Autism

Relatively able children with autism were compared with age- and language-matched controls on assessments of (1) familiar voice-face identity matching, (2) familiar face recognition, and (3) familiar voice recognition. The faces and voices of individuals at the children's schools were used as stimuli. The experimental group were impaired relative to the controls on all three tasks. Face recognition and voice recognition correlated significantly with voice-face identity matching, but not with each other, suggesting that the recognition impairments jointly cause the matching impairment. Neither chronological age nor verbal mental age were consistently related to the recognition and matching impairments.     

Remote memory in epilepsy

PURPOSE: There is now a considerable amount of research relating to memory functioning in epilepsy. The majority of studies have focused on the retention of new information, and few reports have measured memory for past events. This study aims to redress this and measure the efficiency of remote memory in epilepsy. METHODS: A remote memory questionnaire was prepared and administered to three groups of patients with epilepsy and a control group without epilepsy. The questionnaire assessed knowledge of public events that occurred between 1980 and 1991, inclusive. The epilepsy groups comprised 33 patients with temporal lobe epilepsy (TLE), 33 with extratemporal epilepsy (ExTE), and 10 with primary generalized epilepsy (PGE). Thirty control subjects were tested. RESULTS: Patients with TLE performed significantly less well on the questionnaire than all other groups (p = 0.001), but no effect of laterality was recorded; patients with extratemporal or primary generalised epilepsy did not differ from controls. Performance on the questionnaire was not determined by verbal IQ, educational achievement, social class, or drug treatment, but was related to the number of generalised convulsions that had occurred since 1980. The strongest neuropsychological predictors of performance on this questionnaire were measures of verbal memory. CONCLUSIONS: The study demonstrated weak memory for past events in patients with TLE, thereby providing evidence of a broader memory disturbance in this group than has been previously highlighted. A test of remote memory, such as the one designed for this study, is easy to administer and provides clinically important information not available from conventional neuropsychological tests.     

用金属磁记忆方法进行缺陷检测

介绍了金属磁记忆检测的原理及其应用方法。铁磁性工件在载荷的作用下,应力和变形集中区会产生最大的漏磁场变化,对漏磁场法向分量的测定可以准确地推断工件的应力集中区。通过对14块对接焊缝钢板分别用磁记忆、超声波方法进行实际检测,验证了磁记忆检测方法的有效性,取得了一些有益的经验。     

多种工作模式的踝关节活动器的研制

各种原因导致患者长期卧床后将引起严重的并发症:踝关节跖屈畸形。新型踝关节活动器以大扭矩、超低速电机为动力,结合定时控制电路,具有多种工作模式,能使踝关节在被动的情况下背伸20～30°,跖屈40～50°,并能根据患者的个体情况设置不同的运用角度与时间,且能根据需要进行缓慢、连续、往返式运动,这对那些踝关节不能或较难进行主动活动的病人防止踝关节跖屈畸形、踝关节僵硬的及下肢肌肉萎缩有良好的作用。