Octopuses (Octopus bimaculoides) and cuttlefishes (Sepia pharaonis, S. officinalis) can conditionally discriminate

In complex navigation using landmarks, an animal must discriminate between potential cues and show context (condition) sensitivity. Such conditional discrimination is considered a form of complex learning and has been associated primarily with vertebrates. We tested the hypothesis that octopuses and cuttlefish are capable of conditional discrimination. Subjects were trained in two maze configurations (the conditions) in which they were required to select one of two particular escape routes within each maze (the discrimination). Conditional discrimination could be demonstrated by selecting the correct escape route in each maze. Six of ten mud-flat octopuses (Octopus bimaculoides), 6 of 13 pharaoh cuttlefish (Sepia pharaonis), and one of four common cuttlefish (S. officinalis) demonstrated conditional discrimination by successfully solving both mazes. These experiments demonstrate that cephalopods are capable of conditional discrimination and extend the limits of invertebrate complex learning.     

Mangabeys (<Emphasis Type="Italic">Cercocebus torquatus lunulatus</Emphasis>) solve the reverse contingency task without a modified procedure

Problem solving often relies on generating new responses while inhibiting others, particularly prepotent ones. A paradigm to study inhibitory abilities is the reverse contingency task (Boysen and Berntson in J Exp Psychol Anim Behav Process 21:82–86, 1995), in which two different quantities of food are offered to an individual who receives the array he did not choose. Therefore, mastery of the task demands selecting the smaller quantity to obtain the larger one. Several non-human primates have been tested in the reverse contingency task. To date, only great apes and rhesus monkeys (Macaca mulatta) have succeeded in the original task, with no need of procedural modifications as the large-or-none contingency, correction trials or symbolic stimuli substituting for actual food quantities. Here, four mangabeys were presented with two stimulus arrays of one and four raisins in the context of the reverse contingency task. Three of them learned to perform the task well above chance without a modified procedure. They also reached above-chance performance when presented with two stimulus arrays of zero and four raisins, despite the initial difficulty of choosing a null quantity. After a period of 7–10 months, in which the animals were not tested on any task, all three subjects continued to perform well, even when presented with novel quantity pairs.     

Manipulating establishing operations to verify and establish stimulus control during mand training

Acquisition of verbal behavior is a major goal of interventions for children with developmental disabilities. We evaluated the effectiveness of manipulation of an establishing operation for functional discriminated mands. Four individuals with developmental disabilities participated in a training procedure designed to teach two separate mands for two separate preferred items. Participants were taught to mand using picture cards. Following training, the manipulation of the establishing operation was used to assess and establish discriminated manding. This manipulation involved providing free access to one of the preferred items, such that there should be no motivation to ask for it, while motivation to ask for the other item remained in place. Three of the 4 participants acquired discriminated manding using topographically similar responses (picture cards). One participant did not acquire a discriminated mand until topographically distinct mands were taught (vocal and picture card). Results suggest that discrimination training is not necessarily sufficient to teach discriminated manding when more than one picture card showing preferred items is used. In addition, manipulation of the establishing operation served as an appropriate assessment tool for the verification of discriminated manding as well as a possible training tool to establish discriminated manding.     

类别表征与策略的脑科学研究及对思维教学的启示

脑科学研究表明,分类中对物体的知觉表征激活颞下叶皮层和颞中区等区域;语义表征激活前额皮层等。语义加工和知觉表征相互作用的脑机制表现为额区与视觉区域间信息的传递、提取。分类策略主要有规则策略和相似性策略两种。规则策略激活额区等广泛区域;相似性策略与视觉区域相关,包含着对个别样例的记忆过程。基于以上研究结果,本文从学习材料的表征和对材料进行表征时的策略两个方面为思维教学提出了一些建议。     

An analysis of instructor- and tablet-presented conditional discriminations: Fidelity and rapidity

Matching-to-sample arrangements are commonly used to teach conditional discriminations. In these arrangements, instructors must systematically arrange instruction to ensure that a learner's response comes under the intended sources of stimulus control. Given the multitude of instructional considerations, the instructors' procedural fidelity has been a significant concern. Recently, LeBlanc et al. found that brief training and access to enhanced data sheets produced high levels of fidelity with experienced service providers. The current study extended LeBlanc et al. by examining the effects of a similar training on the fidelity and instructional pacing by participants with and without previous experience. The participants' performance was also compared when using a flashcard or binder (i.e., printed) arrays and relative to a tablet-delivered instructional program. High levels of fidelity were observed following training, although pacing was slow. Slight differences in performance were observed across comparison arrays; nevertheless, the tablet-based program outperformed instructors.     

Perceptual and positional saliencies influence children’s sequence learning differently with age and instructions at test

There is growing evidence that, faced with a complex environment, participants subdivide the incoming information into small perceptual units, called chunks. Although statistical properties have been identified as playing a key role in chunking, we wanted to determine whether perceptual (repetitions) and positional (initial units) features might provide immediate guidance for the parsing of information into chunks. Children aged 5 and 8 years were exposed to sequences of 3, 4, or 5 colours. Sequence learning was assessed either through an explicit generation test (Experiment 1) or through a recognition test (Experiment 2). Experiment 1 showed that perceptual and positional saliencies benefited learning and that sensitivity to repetitions was age dependent and permitted the formation of longer chunks (trigrams) in the oldest children. Experiment 2 suggested that children became sensitive to perceptual and positional saliencies regardless of age and that the both types of saliencies supported the formation of longer chunks in the oldest children. The discussion focuses on the multiple factors intervening in sequence learning and their differential effects as a function of the instructions used at test to assess sequence learning.     

社会支持和歧视知觉对流动儿童孤独感的影响:一项追踪研究

为了探讨流动儿童孤独感、歧视知觉、社会支持随时间变化的特点,以及社会支持、歧视知觉对孤独感的影响作用及机制,本研究从北京市公立学校和打工子弟学校选取1164名流动儿童,采用问卷调查的形式对流动儿童的孤独感、歧视知觉和社会支持进行了为期一年的追踪测查,回收有效追踪数据680份。对前、后测均参加的680名被试数据进行分析发现:(1)随着进入城市时间的增长,流动儿童的孤独感和歧视知觉显著减少,报告的社会支持显著增加;(2)流动儿童报告的社会支持、歧视知觉与孤独感之间是相互作用的动态过程。前测的歧视知觉和报告的社会支持共同影响前测孤独感;同时,前测孤独感又会影响后测歧视知觉和报告的社会支持,进而影响后测孤独感。并且在这个动态作用过程中,前、后测社会支持既能分别直接影响前、后测孤独感,前测社会支持还能通过后测社会支持和歧视知觉间接影响后测孤独感;而前、后测歧视知觉则只能分别直接影响前、后测孤独感;(3)前测歧视知觉和社会支持都不能直接影响后测的孤独感,而是需要通过影响后测歧视知觉和社会支持才能对后测的孤独感产生作用。     

Psychophysics of Remembering: The Discrimination Hypothesis

In a psychophysical approach to remembering, the events to be remembered are discriminated from other possibilities at the time of remembering, and not at the time of encoding or learning. The discrimination is specific to the retention interval at which remembering occurs, as shown by experiments demonstrating that discriminability and response bias are delay–specific. This article discusses a discrimination model for remembering that emphasizes the individual's history of learning about reward payoffs in similar experiences in the past. This model predicts the two characteristics of forgetting functions, initial discriminability and rate of forgetting.     

Searching for Evidence of Transfer between Drug Facilitators

Four autoshaping experiments with pigeons examined the transfer of facilitation between drug stimuli. In Experiment 1 the presence and absence of methadone or phencyclidine signaled which of two keylight CSs were followed by grain (US). A different keylight CS was reinforced in the absence of the drugs. The drugs facilitated responding to the CS with which they were trained but did not facilitate responding to the CS reinforced in the presence of the other drug. Thus, transfer of facilitation across drug stimuli was not obtained. In Experiment 2 one of the drug facilitators was replaced by a tone. No evidence of transfer of facilitative function was obtained between the tone and the remaining drug facilitator. In Experiment 3 transfer was again not found using a design similar to that used in Experiment 1 except that the drugs did not simultaneously signal nonreinforcement of a keylight CS. In Experiment 4 the procedures of Experiment 1 were employed except that drug facilitators were replaced by distinct visual stimuli surrounding the response key. Clear evidence of transfer between the visual facilitators was obtained. The lack of transfer of modulatory control by drug stimuli in Experiments 1-3, coupled with its occurrence in Experiment 4 and previous studies, suggests that stimulus control by drugs may differ in important ways from stimulus control by conventional stimuli.