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11.
Rats trained to reach for food pellets into a narrow tubular feeder consistently prefer to perform this stereotype instrumental movement with either the left or right forepaw. In 16 rats with established handedness electrodes were implanted into both lateral hypothalami. The animals were rewarded by intracranial self stimulation (ICSS, 300 msec, 50 Hz, 20-60 microA) for reaching into a modified feeder for a plastic ball operandum, the movement of which between the bottom and entrance of the feeder was monitored by mechanical contacts. The rats readily continued to reach when ICSS was delivered immediately after the photoelectrically detected reach or after the displacement of the operandum. Most rats learned in a single session to modify the movement when ICSS delivery was made contingent upon holding the operandum between the bottom and entrance of the feeder for 256 or 512 msec. The efficiency of reaching (ratio of successful reaches to all reaches) decreased with increasing holding time; only a few animals were able to master a 1024 msec delay. Reaching was supported by ICSS of either lateral hypothalamus. Whereas in 8 rats the strongly expressed forepaw preference was not changed by lateralized ICSS, in 8 latently ambidextrous animals stimulation of the lateral hypothalamus ipsilateral to the preferred forepaw increased reaching with the normally non-preferred forepaw from 15% to 60%. Stimulation of the lateral hypothalamus contralateral to the preferred forepaw did not change the preference. The preference shift was equally well expressed in simple and difficult versions of the task. It is concluded that lateralization of motivational influences can be reflected in the asymmetry of the neural mechanisms processing the lateralized sensory signals and/or elaborating the lateralized motor output. 相似文献
12.
Factors related to postmenopausal muscle performance: a cross-sectional population-based study 总被引:2,自引:0,他引:2
Sirola J Rikkonen T Kröger H Honkanen R Tuppurainen M Airaksinen O Saarikoski S 《European journal of applied physiology》2004,93(1-2):102-107
The aim of the present study was to investigate cross-sectionally the association of postmenopausal muscle strength with simple performance tests. A random sample of 1,166 naturally postmenopausal women (born 1932–1941) was selected from the Kuopio Osteoporosis Risk Factor and Prevention (OSTPRE) study cohort. Grip and quadriceps strength were measured with strain gauge dynamometers and reported in both absolute values (KPa and kg) and per kilogram of body mass (N cm–2 kg–1 and N kg–1). In addition, two performance tests, ability to stand on one foot and ability to squat down to touch the floor were carried out. A five-category self-assessment of overall health (very good, good, moderate, bad, and very bad) was obtained by postal questionnaire. The women that were able to stand on one foot and able to squat down to touch the floor had greater grip and quadriceps strength than their counterparts (P<0.001 and P<0.03 in ANOVA, respectively). In addition, self-assessed health had a strong positive association with muscle strength in the grip and leg extensor muscles in ANOVA (P<0.001 between very good and moderate or poorer state of health) and regression model (P<0.001). Adjustment for age, duration of menopause, body mass, height, physical activity level, use of HRT, and number of diseases and medications did not change any of the main effects. Also, there were no differences in results between absolute measurement values and values reported per kilogram of body mass. According to the present study, a simple performance test may be useful in the prediction of postmenopausal muscle strength. Furthermore, self-assessed state of health is strongly associated with muscle strength in postmenopausal women. 相似文献
13.
初三学生成就动机与学业成绩的关系研究 总被引:2,自引:1,他引:2
张娜 《中国健康心理学杂志》2003,11(6):464-468
编制中学生成就动机量表 ,考察 2 86名初三学生的成就动机状况。运用逐步回归分析探讨成就目标、归因方式、自我效能与学业成绩的关系 ,并对成就目标进行自我效能和归因方式的回归分析。结果表明 :影响初三学生学业成绩的主要成就动机因素是自我效能、表现目标、能力归因和掌握目标 ,努力归因、运气归因和自我效能是影响初三学生成就目标的主要因素 ,客观因素归因也会影响表现目标。对研究结果进行本土化思考 ,建构中学生成就动机的理想模型 相似文献
14.
The fact that electrical stimulation of the lateral hypothalamus (LH) can be substituted for the delivery of a food pellet in typical schedule induced polydipsia was established and demonstrated the role of this part of the brain in the mediation of adjunctive behavior. The assumption that Δ9-tetrahydrocannabinol (Δ9-THC) and ethyl alcohol affect behavior because of a differential effect on the same LH mechanism was supported by the following evidence. Relatively small doses of Δ9-THC, 0.25, 0.375, and 0.50 mg/kg, enhanced adjunctive drinking; whereas, larger quantities of 0.625 and 0.75 mg/kg had no appreciable effects. The effect is somewhat specific, as it did not occur with strychnine sulfate, and rate dependent within limits as it was most pronounced in animals with low rates of responding or in animals when responding at a low rate. The effect of rate dependency was also apparent with fixed interval schedules of 2 and 4 min and a multiple schedule of a fixed interval and a signalled timed out period of nonreinforcement. Low rates of responding were enhanced by all doses of Δ9-THC, 1.0, 1.5, 2.0, 2,5, and 3.0 mg/kg, and there was an obvious dose related decrease in high rates. A similar effect was observed with low and high rates of electrical self-stimulation through implanted LH electrodes. The hypothesis that some drugs such as Δ9-THC and ethyl alcohol can enhance the positive feedback in an LH mediated motor control system by the facilitation of the same mechanism which initially generated the behavior was confirmed. Oral self administration of ethyl alcohol in a saccharin sweetened fluid enhanced recovered adjunctive drinking of the solution in quantities which should be sufficient to produce physical dependence if continued for relatively long periods. Recovered adjunctive drinking occurs in animals without food or water deprivation and it is an intense and persistent phenomenon. 相似文献
15.
住院精神分裂症患者自测健康的对照研究 总被引:7,自引:2,他引:5
目的:比较住院精神分裂症患者和躯体疾病患者的健康状况,及了解影响精神分裂症患者健康的因素。方法:采用“自测健康评定量表”(SRHMS)对81例慢性精神分裂症康复期患者和82例躯体疾病病人作自我评定,进行对照研究,并对相关因素作多元逐步回归分析。结果:两组间SRHMS总分、心理健康子量表总分比较不存在显著性差异;(P=0.39);生理及健康子量表及总分,社会健康子量表总分两组间的差异均有非常显著性差异(P=0.00)。经多元逐步回归分析,精神分裂症组病程,IPROS总分、服药剂量影响SRHMS的评分。结论:自测健康评定量表是健康测定的一个有效工具,测试结果反映了两组人群实际健康状况。 相似文献
16.
强制戒毒期海洛因依赖者自测健康的对照分析 总被引:3,自引:1,他引:2
目的 探讨强制戒毒期海洛因依赖者自测健康状况。方法 对60名强制戒毒者及60名社区人员采用自测健康评定量表(SRHMS)进行评定。结果 强制戒毒患者的SRHMS总分、生理、心理和社会健康因子分均明显低于社区组,两者之间的差异具有非常显著性意义(P<0.01)。结论 吸毒严重损害人们的生理、心理及社会健康,提示要采取措施加强对该人群的心理行为干预及监督管理。 相似文献
17.
糖尿病患者饮食的自我调控单因素回归分析 总被引:3,自引:0,他引:3
目的 研究糖尿病患者饮食和自我调控的关系。方法 采用问卷法和访谈法。结果 经过对与饮食相关的诸因素进行Logistic单因素分析,每次喝酒量的多少,家人对饮食疗法执行的支持情况,性别等三项指标,其OR值均大于1,是正调控因素。说明自我调控越强喝酒越少;家人越支持饮食疗法执行情况越好;男性的自我调控力在执行饮食疗法时比女性高,测血糖的时间,OR值小于1,自我调控力越高的人测血糖越定时。结论 饮食疗法的控制和自我调控力并非正相关。 相似文献
18.
Shunsuke Ohji Yosuke Kimura Yuhei Otobe Naohito Nishio Daisuke Ito Ryota Taguchi Hideyuki Ogawa Minoru Yamada 《The journal of spinal cord medicine》2021,44(2):262
Objective: Although the propulsion distance of a wheelchair is measured by some devices, measuring self-propulsion distance, excluding assistance propulsion distance by the caregiver, is difficult. This is a pilot study conducted to verify whether the propulsion distance of wheelchair users, excluding the assistance propulsion distance, can be measured using a cycle computer by attaching the touch switch.Methods: The wheelchair propulsion distance was measured using a cycle computer. We connected the touch switch and the cycle computer to the wheelchair to exclude assistance propulsion distance. We set the cycle computer to stop recording while the caregiver was touching the sensor. To confirm the propulsion distance using the cycle computer, the volunteer propelled the wheelchair on a rectangular facility with a total distance of 181 m, and the examiner confirmed the propulsion distance. The validation test to confirm the accuracy of the touch switch attached to the cycle computer was performed on a 50-m straight runway. The volunteer and caregiver propelled the wheelchair alternately by 10 m and continued until 50 m. The examiner confirmed the distance after 50-m propulsion.Results: In the 181-m rectangular facility, the propulsion distance that the volunteer propelled the wheelchair with the cycle computer was 180 m. In the 50-m straight runway, the propulsion distance was 30 m with caregiver assistance for 20 m.Conclusion: The present study showed that our modified device could measure the self-propulsion distance, excluding assistance propulsion distance in wheelchair users. 相似文献
19.
B L Strehler 《Synapse (New York, N.Y.)》1991,7(1):44-91
The enigmatic nature of the experience of self-awareness is examined in the light of recent discoveries and, on this basis, combined with inferences derived introspectively from the experience of the phenomenon itself; a specific physical locus of this experience within the human brains is deduced-proposed. The fundamental premise in this work is that whereever conscious self-awareness is generated, the neuronal structure(s) involved must continually have access to an extremely precise representation of information derived from the sense of vision plus a great variety of other kinds of information so as to permit it to make decisions regarding actions (movements and their implementation) that promote the survival and perpetuation of the biological system in which the self is generated. First, a definitve set of criteria that define most of the inputs to and operations carried out by the self-awareness entity were assembled. This ensemble of functions was then compared with the connections and possible roles of specific neuroanatomical structures described in published literature, particularly the recent literature and particularly that concerned with the sense of vision. It was discovered that only one brain structure receives the prerequisite information from the sense of vision plus information derived from cortical memory stores plus a variety of other relevant sources needed to generate a coherent sense of selfness. This structure is the superior colliculus of the tectum. The superior colliculi not only receive a highly precise retinotopic representation of inputs to the eyes, but also receive inputs from a great variety of other structures, including many areas of the cerebral cortex, vestibular inputs, auditory inputs, "affective" inputs, and inputs that putatively define the positions of the eyes and of the head. This information, it is deduced, not only allows this structure to generate a continuing synthesis of representations of the self-vs.-environment, but also allows a part of it to assess the significance (probable meaning) of these integrated inputs with respect to the selection of an implementation of actions that serve the interests of the physical structure in which the self-experience is generated. The function of memory in this system not only involves the continually updated representation of where the self is with respect to items and objects in its environment, but also provides means through which the relevance of recorded experiences representing the past may be caused to affect the decision-making process.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
20.
目的 探讨膀胱全切术后尿流改道新方法即体外可控性回肠代膀胱术的可行性及疗效。方法 取一段回肠 ,将中间部分折叠成N形并缝制成贮尿囊 ;远端回肠从腹壁造瘘口穿出体外 ,于此处取腹壁皮瓣包绕外露肠管缝制成皮管 ,构建输出道 ;将尿液控制器置于皮管外 ,利用气囊控制排尿。结果 10只杂交狗顺利度过手术期 ,术后 3月时贮尿囊最大容量为 (15 0± 4 0 )ml,最大充盈压为 (2 4 .4± 5 .3)cmH2 O。临床应用 5例 ,随访 (3~ 14 )月 ,术后 3月时贮尿囊最大容量达 (2 90± 80 )ml,最大充盈压为 (36 .3± 8.2 )cmH2 O ,最大尿流率为 (2 0 .3± 4 .7)ml s,无残余尿。X线影像学检查 ,肾脏显影良好 ,输尿管通畅。尿液控制器的气囊充气后 ,无尿液流出 ;气囊消气后 ,尿液呈粗线条流出。结论 该尿流改道术式具有体外自主控制排尿的特点 ,不必佩戴集尿袋或自行导尿 ,且手术操作比较简单、并发症少、安全可靠。 相似文献