Resistance To Change As A Function Of Stimulus-reinforcer And Location-reinforcer Contingencies

Pigeons responded on two keys in each component of a multiple concurrent schedule. In one series of conditions the distribution of reinforcers between keys within one component was varied so as to produce changes in ratios of reinforcer totals for key locations when summed across components. In a second series, reinforcer allocation between components was varied so as to produce changes in ratios of reinforcer totals for components, summed across key locations. In each condition, resistance to change was assessed by presenting response-independent reinforcers during intercomponent blackouts and (for the first series) by extinction of responding on both keys in both components. Resistance to change for response totals within a component was always greater for the component with the larger total reinforcer rate. However, resistance to change for response totals at a key location was not a positive function of total reinforcement for pecking that key; indeed, relative resistance to extinction for the two locations showed a weak negative relation to ratios of reinforcer totals for key location. These results confirm the determination of resistance to change by stimulus—reinforcer contingencies.     

Within-session Changes In Responding During Concurrent Variable-interval Schedules

Five rats and 4 pigeons responded for food delivered by several concurrent variable-interval schedules. The sum of the rates of reinforcement programmed for the two components varied from 15 to 480 reinforcers per hour in different conditions. Rates of responding usually changed within the experimental session in a similar manner for the two components of each concurrent schedule. The within-session changes were similar to previously reported changes during simple schedules that provided rates of reinforcement equal to the sum of all reinforcers obtained from the concurrent schedules. The number of changeovers also changed within sessions in a manner similar to the changes in instrumental responding. These results suggest that changeovers are governed by the same variables that govern instrumental responding. They also suggest that the within-session change in responding during each component of a concurrent schedule is determined by approximately the sum of the reinforcers obtained from both components when both components provide the same type of reinforcer.     

Influence of the initial projection of the centre of gravity on posturo-kinetic coordination in humans. Application from a horizontal quadrupedal stance during voluntary limb raising

The purpose of the study is to investigate the influence of initial projection of the centre of gravity (CG) on the spatial and temporal organization of the dynamic phenomena accompanying a voluntary movement in humans. From a horizontal quadrupedal stance, ten normal subjects were instructed to raise the right forelimb towards a support target in self paced velocity conditions. Three experimental conditions were tested for which the initial CG projection was either within (C1), at the limits of (C2) or outside the supporting triangle (C3). The results showed that vertical force variations on the four supports always preceded the first vertical displacement of the right wrist (onset of the movement). From C1 to C3, the duration of these anticipatory dynamic phenomena increased enabling an adjustment of the CG position such that equilibrium constraints were fulfilled. For all conditions, the acceleration peak of the CG occurred prior to the onset of movement and from C1 to C3, its magnitude increased in a single direction of the horizontal plane. For each condition, the load transfer was directed to the left forelimb and the right hindlimb (diagonal strategy) and reached a maximal value at the time of lift-off. With respect to this moment, the onset of the movement occurred increasingly early from C1 to C3. These results suggest that contribution of peripheral cues to postural control is more important, when the requirements of horizontal CG displacement increase.     

思维定势浅议

思维定势是指人们在思维过程中自觉或不自觉地形成的一种比较稳定的思维趋向．由于思维的惯性作用,人们往往频向于以原有的知识和经验去对待和衡量新的信息．思维定势的形成,主要是由一子思维的参照系数大小,思维主体长期接受同一信息的频繁刺激而造成的．思维定势在思维过程中有积极的一面,当思维主体原有的知识和经验与新信息相一致时,主体凭经验即可对事物作出正确的判断．但是当思维主体原有的知识和经验与新信息发生矛盾时,思维定势便呈现出消极影响。在这种情况下,由于思维主体总是趋向于用老经验老方法去解释新信息,而不愿意…     

创意就是财富

进入九十年代以来,美国一些著名的报刊,如《时代周刊》、《美国新闻与世界导报》、《成功）、《商业周刊》、《新闻周刊）等纷纷报道了在美国企业中悄然兴起的一项新的运动──创意训练,称这是美国企业在日趋复杂的竞争中寻求生存和发展的新手段．有人甚至断言,这将带来美国企业发展的一场革命,一个创意的时代即将来临。所谓创意,就是创新．任何一个管理者都清楚地知道：没有创新,就没有发展。现代企业掌握竞争优势的秘诀,不再仅是埋头苦干,抱守以往牵行的成功经典模式而已,而应当是求新求变,不断创新,企业需要新的创意以保持创…     

爱的逻辑

爱的逻辑常常不合逻辑,它总是拿规范意义上的逻辑开涮。例如,规范意义上的“打”与“骂”总是恶煞煞的．可民间却偏偏有一句描写爱情的话叫“打是亲骂是爱”,自然,仅此一句,也就道出了爱的逻辑的博大精深．那么．爱的逻辑何样？爱的逻辑玄奥无比：冬天和心爱的人在一起,你会不觉得冷！夏天和心爱的人在一起。你会不觉得热！“把你架在火上烤三分钟,您会觉得象烤了三年,可让你在心上人旁边坐三年,你会觉得才坐了三分钟！”爱的逻辑喜欢“自相矛盾”：陪你逛街的那个女孩子其实早就累了,可她却偏偏笑眯眯地问：“你累了吗？”爱你的…     

辩证思维

辩证思维区分为朴素辩证思维与理性辩证思维。朴素辩证思维是人们按照世界运动、发展和变化的本来面貌如实地反映世界,是自发地对自然界中到处存在的对立统一运动的反映,即人们未自觉掌提辩证法之前所进行的辩证思维,正像人们远在散文这一名词出现以前,就已经在用散文说话一样．理性辩证思维是人们自觉运用辩证法观点,接照辩证法的基本要求所进行的思维。这种思维是一种主观辩证法,是对客观辩证法的自觉运用．因此,只有精通并自觉运用辩证法的人,才能有理性辩证思维．同形而上学思维相比,理性辩证思维有下述四个特征：（1）全面性…     

能力──竞争实力的核心

现代社会是市场经济的社会。经济、政治、文化等各个领域,都充满着竞争的搏击。任何人参加竞争,既要靠客观条件,如拥有资本、历史机遇等等;又要靠主观条件,如知识丰富、聪明睿等等．靠什么具备这些条件？人的能力．拥有资本靠人的能力创造,历史机遇靠人的能力抓住,知识丰富靠人的能力获得,聪明睿智靠人的能力炼成。竞争实力来自竞争能力．人们总是度稳量力,凭借能力,参加竞争。竞争关系就是能力关系：能力强,竞争胜;能力弱,竞争败。竞争的能力从哪里来？我们自然会想到“知识就是力量”的名言。然而,知识并不等于能力。有的人…     

见微知著与全息方法

聪明来源于丰富的知识储备,更来源于高超的思维能力─—一见微知著。世间最可贵和神奇的聪明是“一叶知秋”,即在受客观条件多方限定而所获很少信息的条件下,了解了事物的内在规律或发展趋向。在人们的日常生活中,更多的遇到的是这般信息量不足而时间又不允许决策滞延的情景。在这种情况下,人们决策的英明和远识．来源于反映客观事物内在规律性的全息认识方法的运用水平。所谓全息方法,是人们依据客观事物的普遍联系和因果制的唐钢．涌村了历事物的部分信息去认识事物整体的方法。现代科学证明,一粒沙子,包含无限宇宙的奥秘;一枚古…