Formation of the sameness-difference concept by Japanese monkeys from a small number of color stimuli

Japanese monkeys were trained to form the sameness-difference concept. In Experiment 1, four monkeys were trained with two colors to discriminate matching stimulus pairs from nonmatching pairs by reinforcing only lever-pressing responses to matching pairs with a variable-interval schedule. Three monkeys showed successful transfer of this discrimination to two new colors, thus demonstrating that some Japanese monkeys are able to form this relational concept from a minimum number of stimuli. In Experiment 2, two monkeys were trained, in a Yes/No procedure with three colors, to press one lever under matching pairs and another lever under nonmatching pairs. Poor transfer performances to three new colors suggest that simultaneously establishing two different response patterns to matching and nonmatching pairs is ineffective in forming the concept. In Experiment 3, the amount of transfer to three new colors after mastering a standard three-color matching-to-sample task was compared with that of a modified task in which correct responses were reinforced with a within-trial variable-interval schedule. All three monkeys showed greater transfer with the modified procedure. The results suggest that the variable-interval schedule adopted within trials is effective in forming the sameness-difference concept.     

Observational learning in capuchin monkeys: a video deficit effect

Young human children have been shown to learn less effectively from video or televised images than from real-life demonstrations. Although nonhuman primates respond to and can learn from video images, there is a lack of direct comparisons of task acquisition from video and live demonstrations. To address this gap in knowledge, we presented capuchin monkeys with video clips of a human demonstrator explicitly hiding food under one of two containers. The clips were presented at normal, faster than normal, or slower than normal speed, and then the monkeys were allowed to choose between the real containers. Even after 55 sessions and hundreds of video demonstration trials the monkeys’ performances indicated no mastery of the task, and there was no effect of video speed. When given live demonstrations of the hiding act, the monkeys’ performances were vastly improved. Upon subsequent return to video demonstrations, performances declined to pre-live-demonstration levels, but this time with evidence for an advantage of fast video demonstrations. Demonstration action speed may be one aspect of images that influence nonhuman primates’ ability to learn from video images, an ability that in monkeys, as in young children, appears limited compared to learning from live models.     

Note on aversion learning to the shape of food by monkeys

Vervet and grivet monkeys were repeatedly tested eating bar- and circle-shaped cookies. One subject was always injected with lithium immediately after eating cookies with the circle shape and learned to avoid the circular cookies while continuing to eat the bar-shaped cookies. Another subject received similar treatment except that lithium injections were always delayed 30 minutes after access to the circle-shaped cookies. She also acquired a discriminative aversion. Aversion learning was not observed with 60-minute delayed toxicosis or with lithium injections administered unpaired with access to the cookies. The two types of cookies differed only in shape, and conditioning and test sessions were conducted in total darkness to preclude the use of visual cues. Therefore, the avoidance observed in subjects conditioned with immediate and 30-minute delayed toxicosis represents a conditioned aversion to the shape of the cookies as revealed by tactile cues. These findings illustrate that monkeys can learn to select food on the basis of tactile stimuli when such stimuli are conditioned with delayed aversive stimulation.     

Effects of ratio reinforcement schedules on discrimination performance by Japanese monkeys

In Experiment 1, Japanese monkeys were trained on three conditional position-discrimination problems with colors as the conditional cues. Within each session, each problem was presented for two blocks of ten reinforcements; correct responses were reinforced under continuous-reinforcement, fixed-ratio 5, and variable-ratio 5 schedules, each assigned to one of the three problems. The assignment of schedules to problems was rotated a total of three times (15 sessions per assignment) after 30 sessions of acquisition training. Accuracy of discrimination increased to a moderate level with fewer trials under CRF than under ratio schedules. In contrast, the two ratio schedules, fixed and variable, were more effective in maintaining accurate discrimination than was CRF. With further training, as asymptotes were reached, accuracy was less affected by the schedule differences. These results demonstrated an interaction between the effects of reinforcement schedules and the level of acquisition. In Experiment 2, ratio sizes were gradually increased to 30. Discrimination accuracy was maintained until the ratio reached 20; ratio 30 strained the performance. Under FR conditions, accuracy increased as correct choice responses cumulated after reinforcement.     

Complex learning and information processing by pigeons: a critical analysis

Three models of conditional discrimination learning by pigeons are described: stimulus configuration learning, the multiple-rule model, and concept learning. A review of the literature reveals that true concept learning is not characteristic of the behavior of pigeons in matching-to-sample, oddity-from-sample, or symbolic matching studies. Instead, pigeons learn a set of sample-specific S^D rules. Transfer of the discrimination to novel stimuli, at least along the hue dimension, is predicted by a “coding hypothesis”, which holds that pigeons make a unique, but usually unobserved response, R₁, to each sample, and that the comparison stimulus chosen depends on which R₁ was emitted in the presence of the sample. Convincing evidence is found that pigeons do code sample hues, but there is little evidence that allows one to infer that the “coding event” must have behavioral properties. Parameters of the conditional discrimination paradigm are identified, and it is shown that by appropriate parametric manipulation, a variety of analogous tasks may be generated for both human and animal subjects. The tasks make possible the comparative study of complex learning, attention, memory, and information processing, with the added advantage that behavior processes may be compared systematically across tasks.     

Relational and absolute stimulus learning by monkeys in a memory task.

Three experiments showed stimulus control by either the absolute properties of probe stimuli, relational properties of the probe-list relationship, or both in a serial probe recognition memory task in which a four-item memory list was followed by a single probe (test) item. In Experiment 1, 3 rhesus monkeys received 39 to 75 repetitions of the same 24-trial stimulus sequence. Special tests showed stimulus control by the absolute properties of the probe stimuli. Retention of previous relational control was demonstrated by the good transfer (83%) to novel list and probe stimuli at the beginning of Experiment 2. During Experiment 2, control by absolute properties of the probe stimuli gradually reoccurred. Only a small measure of control by list stimuli could be detected or promoted. In Experiment 3, 4 monkeys were shown to have largely lost their ability to perform on the basis of the list-probe relationship, and were performing primarily on the basis of the absolute properties of the probe stimuli. Over the next 15 weeks, these monkeys were transferred to new stimuli at the beginning of each week. Control by the relational aspects of the task gradually returned. As transfer performance increased, control by the absolute properties of the probe stimuli was eliminated. The results are discussed in terms of stimulus control and performance strategies used by the monkeys.     

Asymmetry of attentional set in rhesus monkeys learning colour and shape discriminations

We trained rhesus monkeys on six visual discrimination problems using stimuli that varied in both shape and colour. For one group of animals shape was always relevant in these six problems, and colour always irrelevant, and for the other animals vice versa. During these “intradimensional shifts” (ID) the problems were learned at equal rates by the two groups, shape-relevant and colour-relevant. We then trained three further problems in which the other dimension was now relevant (“extradimensional shifts”, ED). The animals showed slower learning when shifting from colour-relevant to shape-relevant, but not when shifting from shape-relevant to colour-relevant. These results show that monkeys' ability to selectively attend to a relevant stimulus dimension and to ignore an irrelevant dimension depends on the experimenter's choice of relevant and irrelevant dimensions.     

选择性注意对听觉内隐学习的影响

内隐学习被认为是人类无意识、无目的获得复杂规则的自动化过程。已有研究表明, 在人工语法学习范式下, 视觉内隐学习的发生需要选择性注意。为了考察选择性注意对内隐学习的影响是否具有通道特异性, 本研究以90名大学生为被试, 以人工语法为学习任务, 采用双耳分听技术, 在听觉通道同时呈现具有不同规则的字母序列和数字序列, 考查被试在听觉刺激下对注意序列和未注意序列构成规则的习得情况。结果发现：只有选择注意的序列规则被习得, 未选择注意的序列规则未能被习得。研究表明：在人工语法学习范式下, 只有选择注意的刺激维度能够发生内隐学习。选择性注意对内隐学习的影响具有跨通道的适用性, 不仅适用于视觉刺激, 也同样适用于听觉刺激。     

Effects of GABA modulators on the repeated acquisition of response sequences in squirrel monkeys

The present study investigated the effects of positive and negative GABA(A) modulators under three different baselines of repeated acquisition in squirrel monkeys in which the monkeys acquired a three-response sequence on three keys under a second-order fixed-ratio (FR) schedule of food reinforcement. In two of these baselines, the second-order FR schedule and the discriminative stimuli for the response sequence were manipulated ("chain-strained" and "tandem-strained"). In the third baseline condition, response-independent tail shock was presented during acquisition of the response sequence. All of these baselines maintained high error levels and produced slow rates of acquisition. Under both the chain-strained and tandem-strained conditions, the positive GABA(A) modulator triazolam (0.0032-0.1 mg/kg) and the negative GABA(A) modulators beta-CCE (ethyl-beta-carboline-3-carboxylate; 0.01-1 mg/kg), beta-CCM (methyl-beta-carboline-3-carboxylate; 0.0032-0.1 mg/kg), and FG-7142 (methyl-beta-carboline-3-carboxamide; 0.18-10 mg/kg) dose-dependently decreased overall response rate compared to administration of saline (control). Under the same two conditions, triazolam and the negative GABA(A) modulators also increased the percentage of errors; however, the effects on accuracy frequently depended on the baseline condition and the particular modulator. In contrast, triazolam only decreased errors and enhanced acquisition in the presence of concurrent response-independent tail shock when compared to saline administration under this condition. The neutral GABA(A) modulator, flumazenil (1 mg/kg), had no effect on rate or accuracy of responding when administered alone, but antagonized the rate-decreasing and error-increasing effects produced by the negative GABA(A) modulators. Together, these data suggest that the effects of both the positive and negative GABAA modulators on acquisition can be similar in squirrel monkeys (i.e., both types of modulator may produce rate-decreasing and error-increasing effects) and that their effects on acquisition depend, in part, on the environmental conditions maintaining acquisition.     

Influence of cue word perceptual information on metamemory accuracy in judgement of learning

Previous studies have suggested that perceptual information regarding to-be-remembered words in the study phase affects the accuracy of judgement of learning (JOL). However, few have investigated whether the perceptual information in the JOL phase influences JOL accuracy. This study examined the influence of cue word perceptual information in the JOL phase on immediate and delayed JOL accuracy through changes in cue word font size. In Experiment 1, large-cue word pairs had significantly higher mean JOL magnitude than small-cue word pairs in immediate JOLs and higher relative accuracy than small-cue pairs in delayed JOLs, but font size had no influence on recall performance. Experiment 2 increased the JOL time, and mean JOL magnitude did not reliably differ for large-cue compared with small-cue pairs in immediate JOLs. However, the influence on relative accuracy still existed in delayed JOLs. Experiment 3 increased the familiarity of small-cue words in the delayed JOL phase by adding a lexical decision task. The results indicated that cue word font size no longer affected relative accuracy in delayed JOLs. The three experiments in our study indicated that the perceptual information regarding cue words in the JOL phase affects immediate and delayed JOLs in different ways.     

Auditory statistical learning: predictive frequency information affects the deployment of contextually mediated attentional resources on perceptual tasks

Statistical learning is a general phenomenon in which environmental regularities are implicitly acquired through repeated exposure to those environments. Sometimes, that information can be utilised to affect various aspects of cognitive performance (e.g. reaction time) on tasks that utilise selective attention (e.g. visual search). In the current study, we examined the effect of passively listening to predictive auditory contexts in facilitating attention to a certain frequency or frequency range. In doing so, we found that there is a general tendency for attentional resources to be negatively affected when the context sequences are made novel after context–target associations have been formed (Experiment 1), and when the context no longer reliably cues the previous target (Experiment 2). The experiments are framed to contrast Associative Learning and Memory Hypothesis perspectives.     

Effective use of the blank comparison procedure in simple discrimination by infant capuchin monkeys: A methodological note

In studies of simple and conditional discrimination, procedures are needed to measure those aspects of stimuli that control behavior. The blank comparison procedure is one such procedure. It was designed explicitly for assessing S+ and S- functions when discriminative stimuli are presented simultaneously. In this procedure, a neutral stimulus serves sometimes as S+ and sometimes as S-. Its discriminative function is defined in relation to other stimuli in the display. The present study aimed to prepare 2 infant female capuchin monkeys for the effective use of the blank comparison procedure in a simple discrimination task. First, simple discrimination training was applied up to a stable accuracy criterion of ≥90%. This training was followed by the replacement of S+ and then of S- stimuli with new stimuli. Ultimately, trials with the blank comparison were introduced. Following this sequence, both monkeys immediately displayed highly accurate blank-comparison performances without the need for stimulus control shaping or other preparatory discrimination training. Thus, this procedure sequence may be an efficient, effective method for establishing blank-comparison baselines for experimental analyses of S+/S- discriminative functions and perhaps for other applications in teaching simple and conditional discrimination performances to this species and others.     

Relational learning in a context of transposition: a review

In a typical transposition task, an animal is presented with a single pair of stimuli (for example, S3+ S4−, where plus and minus denote reward and nonreward and digits denote stimulus location on a sensory dimension such as size). Subsequently, an animal is presented with a testing pair that contains a previously reinforced or nonreinforced stimulus and a novel stimulus (for example, S2–S3 and S4–S5). Does the choice of a novel S2 instead of previously reinforced S3 in a testing pair S2–S3 indicate that the animal has learned a relation (i.e., “select smaller”)? This review of empirical evidence and theoretical accounts shows that an organism''s behavior in a transposition task is undoubtedly influenced by prior reinforcement history of the training stimuli (Spence, 1937). However, it is also affected by two other factors that are relational in nature—a similarity of two testing stimuli to each other and an overall similarity of the testing pair as a whole to the training pair as a whole. The influence of the two latter factors is especially evident in studies that use multiple pairs of training stimuli and a wide range of testing pairs comprising nonadjacent stimuli (Lazareva, Miner, Young, & Wasserman, 2008; Lazareva, Wasserman, & Young, 2005). In sum, the evidence suggests that both prior reinforcement history and relational information affect an animal''s behavior in a typical transposition task.     

The exponential learning equation as a function of successful trials results in sigmoid performance

While the exponential learning equation, indicating a gradually diminishing improvement, is one of the standard equations to describe learning, a sigmoid behavior with initially increasing then decreasing improvement has also been suggested. Here we show that the sigmoid behavior is mathematically derived from the standard exponential equation when the independent variable of the equation is restricted to the successful trials alone. It is suggested that for tasks promoting success-based learning, performance is better described by the derived sigmoid curve.     

A search for symmetry in the conditional discriminations of rhesus monkeys, baboons, and children.

Procedures for generating arbitrary matching-to-sample performances may generate only conditional discriminations. Rational grounds for this distinction are proposed, based on the properties that any equivalence relation must possess. Empirical tests are described for determining whether subjects trained on conditional discriminations are also engaged in true matching to sample. A series of studies than leads to the conclusion that proof of true matching to sample by monkeys, pigeons, or baboons is yet to be provided. Whether the absence of such proof reflects experiential factors or species-defined limitations is not presently clear.     

Influence of body-centered information on the transfer of spatial learning from a virtual to a real environment

This study investigated the effects of body-centred information on the transfer of spatial learning using a wayfinding task and tasks that specifically probe the route and survey strategies of navigation. The subject learned a route in either a real or a virtual environment (VE; 3D scale model of a Bordeaux neighbourhood) and then reproduced it in the real environment. The involvement of body-based information was manipulated across the spatial learning conditions in the VE: participants learned with full body-based information (treadmill with rotation), with the translational component only (treadmill without rotation) or without body-based information (joystick). In the wayfinding task, the results showed a significant effect of the learning environment with the best scores obtained in the real and treadmill with rotation conditions. There was no significant difference between these two conditions, but the real condition was significantly different from the treadmill without rotation and joystick conditions. Also, the visual flow was sufficient to successfully perform the two egocentric tasks used as well as a direction estimation task (a survey task), in so far as there is no significant difference between the joystick and the treadmill conditions. By contrast, the distance estimates were improved by the treadmill condition including the translational component (but not the rotational component). Finally, our results show that treadmill with rotation promotes the transfer of spatial learning from a virtual to a real environment (compared to joystick and treadmill without rotation). Moreover, body-centred informations are more involved in allocentric (distance estimates) than egocentric navigational strategies.     

高效率学习的选择性注意研究

本文回顾了视觉加工、双语学习、内隐认知、学习不能与专注力训练等领域的研究成果,从不同层面阐述了选择性注意对高效学习的贡献及其影响因素,为深入研究高效率学习的心理机制提供支持。     

An account of the relationship between fluid intelligence and complex learning in considering storage capacity and executive attention

Although fluid intelligence and complex learning are conceptualized differently and assessed by apparently different measures, both theoretical accounts and empirical evidence suggest a relationship between the two constructs. In this study, major working memory aspects including the storage capacity and executive attention were proposed to account for the relationship between fluid intelligence and complex learning. A sample of 184 participants completed fluid intelligence and complex learning scales, as well as working memory measures that each included two or three treatment levels differing in the demands on capacity or executive control. The differences among the treatment levels provided a favorable precondition for employing fixed-links models to separate the core processes of storage capacity or executive attention from the auxiliary processes. Results indicated that both storage capacity and executive attention contributed significantly to fluid intelligence and complex learning. A further analysis showed that the two working memory aspects, particularly the storage capacity, accounted for most of the shared variance between fluid intelligence and complex learning.     

共享因素对参照性交流双方学习的影响

采用参照性交流学习范式,探查共享因素对双方学习的影响。结果显示:从学习阶段6开始"共享语言+对象+表情"方式的成绩显著高于"共享语言+对象"方式,低分组条件下该方式成绩显著最高,且该方式高、低分组间无显著差异;"共享语言+对象"方式下揭开的维度数量显著最少。表明:"共享语言+对象+表情"方式下学习效率最高,集中表现于低分组学习效率更高且双方协调水平最高;"共享语言+对象"方式的选择性注意水平最低。