COMPARISON OF STAFF TRAINING STRATEGIES TO PROMOTE GENERALIZED TEACHING SKILLS

Two studies compared the effectiveness of different strategies for promoting generalization of staff skills in teaching self-care routines to clients with developmental disabilities. In Study 1, 9 direct-care staff members of group homes were trained sequentially through four conditions: (a) the provision of written instructions, (b) performance-based training using a single client program exemplar and simulated clients (single case training), (c) performance-based training using actual developmentally delayed clients as trainees (common stimuli training), and (d) performance-based training using multiple client program exemplars with simulated clients (general case training). The results indicated that staff members did not reach all generalization criteria until general case training was provided. Because staff members had been trained sequentially through several conditions in Study 1, a second study controlled for potential sequence effects. In Study 2, 7 staff members were trained using only the general case strategy after baseline. All staff members reached generalization criteria with only general case training, replicating the findings of Study 1. Together, the two studies demonstrated that the general case training strategy was more effective at promoting generalized training effects across clients, settings, and client programs than other commonly used staff training approaches.     

Generalization of equivalence relations from photos to objects by preschool children

Generalized equivalence classes are stimulus classes that consist of equivalent stimuli and other physically similar class‐member stimuli. The present study evaluated whether preschool children would form equivalence classes among photos of abstract objects (2D) and show equivalence generalization to the corresponding objects (3D), printed photos (2D stimuli), and to black‐and‐white drawn pictures (2D stimuli). Six typically developing children were taught arbitrary relations to establish three 3‐member equivalence classes with 2D stimuli presented on a computer screen. AB‐AC baseline relations (for half of the participants) and AB‐BC relations (for the other half) were taught using a multiple‐probe design to assess taught and tested relations. After class formation, three types of generalization probes were conducted: generalization to 3D stimuli, generalization between 2D (printed photos) and 3D stimuli, and generalization to drawn pictures (2D). All of the participants formed the equivalence classes. Two participants met the criterion for all three generalization probe types. Two participants presented mixed results across tests, and two participants did not exhibit equivalence generalization. The results demonstrated equivalence generalization from 2D to 3D stimuli in preschool children, although the variability across participants suggests that such generalization cannot be assumed a priori.     

Superordinate categorization via learned stimulus equivalence: quantity of reinforcement, hedonic value, and the nature of the mediator

Three experiments examined superordinate categorization via stimulus equivalence training in pigeons. Experiment 1 established superordinate categories by association with a common number of food pellet reinforcers, plus it established generalization to novel photographic stimuli. Experiment 2 documented generalization of choice responding from stimuli signaling different numbers of food pellets to stimuli signaling different delays to food reinforcement. Experiment 3 indicated that different numbers of food pellets did not substitute as discriminative stimuli for the photographic stimuli with which the food pellets had been paired. The collective results suggest that the effective mediator of superordinate categories that are established via learned stimulus equivalence is not likely to be an accurate representation of the reinforcer, neither is it likely to be a distinctive response that is made to the discriminative stimulus. Motivational or emotional mediation is a more likely account.     

Using Brief Academic Assessments to Determine Generalization Strategies

This study examined the utility of brief academic assessments to identify effective generalization procedures for individual students. Specifically, the study built on the proposal that brief assessments of antecedent and consequence manipulations can identify the most effective generalization strategy for individual students. The design was an alternating treatments design nested within a multiple baseline across six students. Students learned how to solve a set of multiplication facts using a common strategy while spontaneous generalization to other sets of facts was measured. Next, researchers determined whether an antecedent- or consequent-based generalization strategy would be more effective for increasing generalization across multiplication skills and conducted an extended analysis with an alternating treatment phase to confirm results of the brief assessment. Results indicated that the assessment correctly identified the most effective generalization strategy for five of the six students.     

Stimulus hierarchy generalization in systematic desensitization

A group of snake phobic Ss were desensitized to the first 5 items of a standard 7 item snake fear hierarchy in which the items were ordered on the basis of distance from a snake. This group and a no-treatment control group (which did not receive the desensitization) were treated for fear of all the hierarchy stimuli in terms of ratings both before and after the desensitization. The Ss rated their fear responses to all the stimuli as presented to them in (1) real form (2) by slide, and (3) in imaginal form. The results verified all four experimental hypotheses: (1) The experimental Ss showed greater fear reduction than the control Ss to both the training stimuli (the stimuli on which desensitization done) and the generalization stimuli (the other two stimuli), (2) The systematic desensitization (SD) group showed (a) more fear reduction to the last training stimuli than to the lower generalization stimulus and (b) more to the latter than to the higher generalization stimulus, (3) The SD group showed less fear reduction to the generalization stimuli in their real form than in both the slide and imaginai modalities (in the desensitization each stimulus presentation was done first in slide form and then in imaginal form), and (4) There were significant overall individual differences in generalization of fear reduction to the generalization stimuli.     

基于知觉的恐惧泛化的认知神经机制

恐惧泛化是条件性恐惧反应转移到另一个相似但安全的刺激的现象。适当的恐惧泛化对人类有积极意义, 而过度的恐惧泛化则不利于个体有效地适应环境。基于知觉的恐惧泛化研究揭示了恐惧泛化的规律, 因而被广泛应用。本文首先梳理了对知觉恐惧泛化的相关研究, 介绍恐惧泛化的经典理论基础—巴普洛夫条件反射以及恐惧泛化梯度; 其次简要回顾基于多个感觉通道(即视觉、听觉、情景)的知觉恐惧泛化研究现状; 再次, 分别对海马、杏仁核、脑岛和前额叶等脑区在恐惧泛化中的作用进行回顾, 进一步总结出恐惧泛化的神经环路结构模型。最后, 简要区分了基于知觉的恐惧泛化和正在兴起的基于概念的恐惧泛化, 进而指出未来研究需要结合基于概念的恐惧泛化、区分被试对刺激的辨别力、增加恐惧刺激材料的准确性及多样化、结合激素等个体差异和多模态脑成像数据来展开。     

Infants use rational decision criteria for choosing among models of their input

Previous work demonstrated that 9-month-olds who were familiarized with 3-syllable strings consistent with both a broader (AAB or ABA) and narrower (AAdi or AdiA) generalization made only the latter. Because the narrower generalization is a subset of the broader one, any example that is consistent with the broader generalization but not the narrower one should allow a rational learner to select the broader generalization. The current experiment asked whether infants show evidence of being such learners. Infants who heard the stimuli that previously led to the narrower generalization plus three counterexamples mixed into the last five stimuli made the broader generalization at test. A control condition ruled out the possibility that infants based their generalization on the last five familiarization stimuli. The new findings suggest that infants effectively consider multiple competing models for their input and use rational decision criteria for selecting among these models.     

分类和概念对恐惧泛化的影响机制

恐惧泛化与多种焦虑障碍的病理基础密切相关。例如创伤后应激障碍个体往往持续地逃避与创伤事件有关的刺激,遭受着创伤痛苦折磨。本文在厘清知觉辨别与恐惧泛化关系的基础上,着力于高级认知过程(分类与概念相似性、典型性和人工概念)对恐惧泛化的影响,回顾了恐惧泛化的相关神经机制,并揭示恐惧泛化对焦虑障碍患者的临床治疗启示。未来研究应将知觉和高级认知维度的恐惧泛化进行整合研究,同时扩充恐惧习得和泛化的神经回路,以促进人类恐惧泛化更深入的研究。     

The influence of correlations between noncritical features and reinforcement on stimulus generalization

One strategy to program for generalization is to vary noncritical features in teaching exemplars, thereby avoiding noncritical features from being highly correlated with reinforcement and thus gaining faulty stimulus control. In the current translational evaluation, 2 groups of adults of typical development were taught to respond to arbitrary stimuli with experimenter‐defined critical and noncritical features in a matching‐to‐sample task. The teaching arrangement used for 1 group programmed for low correlation between noncritical features and reinforcement; the teaching arrangement used for the other group programmed for high correlation between noncritical features and reinforcement. Participants in the former group displayed (a) faster acquisition of matching, (b) less variability in correct responding, and (c) a decreased likelihood of faulty stimulus control developing during training. The results contribute towards advancing the study of stimulus control and developing an explicit technology of generalization to better serve consumers of the application of our science.     

Treatment of bisexual pedophilia by a biofeedback-assisted self-control procedure

A bisexual pedophile was treated for 88 days using a biofeedback procedure which displayed his erection response to sexually deviant stimuli on a closed-circuit television monitor. Told to develop a strategy of self-control using the biofeedback, his response to young boys and girls was treated sequentially in a multiple baseline design. His concurrent response to boys, girls and adult males was evaluated in separate generalization sessions. The treatment was successful in suppressing deviant response while maintaining nondeviant response in strength. Debriefing of the client following treatment revealed that he had used a self-developed technique of covert sensitization to suppress deviant response and had used the biofeedback to confirm and validate this self-control strategy.     

Modality effects in memory for basic stimulus attributes: a temporal and nontemporal comparison

Previous research suggests that there are significant differences in the operation of reference memory for stimuli of different modalities, with visual temporal entries appearing to be more durable than auditory entries (Ogden, Wearden, & Jones, 2008 , 2010). Ogden et al. ( 2008 , 2010 ) demonstrated that when participants were required to store multiple auditory temporal standards over a period of delay there was significant systematic interference to the representation of the standard characterized by shifts in the location of peak responding. No such performance deterioration was observed when multiple visually presented durations were encoded and maintained. The current article explored whether this apparent modality-based difference in reference memory operation is unique to temporal stimuli or whether similar characteristics are also apparent when nontemporal stimuli are encoded and maintained. The modified temporal generalization method developed in Ogden et al. (2008) was employed; however, standards and comparisons varied by pitch (auditory) and physical line length (visual) rather than duration. Pitch and line length generalization results indicated that increasing memory load led to more variable responding and reduced recognition of the standard; however, there was no systematic shift in the location of peak responding. Comparison of the results of this study with those of Ogden et al. (2008, 2010) suggests that although performance deterioration as a consequence of increases in memory load is common to auditory temporal and nontemporal stimuli and visual nontemporal stimuli, systematic interference is unique to auditory temporal processing.     

Secondary generalization and categorization in pigeons

In Experiment 1, one group of pigeons learned to classify a set of stimuli into the human language classes cat, flower, car, and chair (categorization); another group learned to classify the same set into arbitrary classes (pseudocategorization). Then, both groups were trained on a new categorization task and their performance compared to that of a control group that had no initial classification training. Hull's (1943) notion of secondary generalization (generalization that is not based on physical similarity but on mediating associations) predicts that categorization experience will facilitate the learning of a new categorization task, whereas pseudocategorization experience will impair it. However, in Experiment 1, performance on the new categorization task was not differently affected by prior experience. In Experiment 2, pigeons initially trained to classify a set of 48 stimuli (original training) were later trained to classify a subset of four of these stimuli using new responses (reassignment training). Then, they were tested on the 44 remaining stimuli. Performance better accorded with original than with reassignment training, indicating that categorization training did not lead to the formation of equivalence classes of stimuli, in which the equivalence relationship is mediated by secondary generalization. The lack of evidence of secondary generalization implies that our pigeons failed to meet Lea's (1984) criterion for conceptual behavior.     

状态焦虑对条件性恐惧泛化的影响

恐惧的过度泛化是焦虑障碍患者重要的潜在病因,探索焦虑对恐惧泛化的影响具有重要意义。本研究在恐惧习得后,通过恐惧创伤电影范式诱发状态焦虑组被试的焦虑水平,采用主观预期值和皮电反应值作为指标,考察状态焦虑对条件性恐惧泛化的影响。结果表明,恐惧创伤电影范式显著提高了状态焦虑组被试的焦虑水平。在泛化阶段,状态焦虑组被试表现出更强的恐惧泛化,对与条件刺激相似的泛化刺激表现出更强烈的恐惧以及更高的预期。状态焦虑使得被试恐惧泛化的消退更慢,持续时间更长。研究同时发现,在状态焦虑下,被试对条件刺激的辨识出现增强趋势。研究结果提示在对经历负性事件个体进行临床干预时,可通过降低其焦虑水平来减少过度泛化。     

Matching- and nonmatching-to-sample concept learning in rats using olfactory stimuli

Previous research has shown that rats can learn matching-to-sample relations with olfactory stimuli; however, the specific characteristics of this relational control are unclear. In Experiment 1, 6 rats were trained to either match or nonmatch to sample in a modified operant chamber using common household spices as olfactory stimuli. After matching or nonmatching training with 10 exemplars, the contingencies were reversed with five new stimuli such that subjects trained on matching were shifted to nonmatching and vice versa. Following these reversed contingencies, the effects of the original training persisted for many trials with new exemplars. In Experiment 2, 9 rats were trained with matching procedures in an arena that provided for 18 different spatial locations for comparison stimuli. Five subjects were trained with differential reinforcement outcomes and 4 with only one type of reinforcer. Differential outcomes and multiple exemplars facilitated learning, and there was strong evidence for generalization to new stimuli for most rats that acquired several conditional discriminations. Performances with novel samples were generally above chance, but rarely reached the high levels obtained during baseline with well-trained stimulus relations. However, taken together, the data from the two experiments extend previous work, show that rats can learn both match and nonmatch relations with different experimental protocols, and demonstrate generalization to novel sample stimuli.     

Stimulus generalization in two associative learning processes

Recent studies involving nonlinear discrimination problems suggest that stimuli in human associative learning are represented configurally with narrow generalization, such that presentation of stimuli that are even slightly dissimilar to stored configurations weakly activate these configurations. The authors note that another well-known set of findings in human associative learning, cue-interaction phenomena, suggest relatively broad generalization. Three experiments show that current models of human associative learning, which try to model both nonlinear discrimination and cue interaction as the result of 1 process, fail because they cannot simultaneously account for narrow and broad generalization. Results suggest that human associative learning involves (a) an exemplar-based process with configural stimulus representation and narrow generalization and (b) an adaptive learning process characterized by broad generalization and cue interaction.     

Stimulus generalization of behavioral history

Undergraduates responded under a variable-ratio 30 schedule in the presence of a 25-mm long line and on a differential-reinforcement-of-low-rate 6-s schedule when a 13-mm long line was present. Following this, a line-length continuum generalization test was administered under a fixed-interval 6-s schedule (Experiment 1) or extinction (Experiment 2). In both experiments, obtained generalization gradients conformed to typical postdiscrimination gradients. Responses were frequent under stimuli physically similar to the 25-mm line and infrequent under stimuli physically similar to the 13-mm line. The generalization gradients were generally asymmetric with peak response rates occurring at line lengths greater than 25 mm.     

Predicting reasoning from memory

In an effort to assess the relations between reasoning and memory, in 8 experiments, the authors examined how well responses on an inductive reasoning task are predicted from responses on a recognition memory task for the same picture stimuli. Across several experimental manipulations, such as varying study time, presentation frequency, and the presence of stimuli from other categories, there was a high correlation between reasoning and memory responses (average r = .87), and these manipulations showed similar effects on the 2 tasks. The results point to common mechanisms underlying inductive reasoning and recognition memory abilities. A mathematical model, GEN-EX (generalization from examples), derived from exemplar models of categorization, is presented, which predicts both reasoning and memory responses from pairwise similarities among the stimuli, allowing for additional influences of subtyping and deterministic responding.     

Generalizing Teaching Techniques from University to K-12 Classrooms: Teaching Preservice Teachers to Use What They Learn

Preservice teachers learn evidence-based practices in university classrooms but often fail to use them later on in their own K-12 classrooms. The problem may be a missing link in teacher preparation, i.e., failure to teach preservice teachers to generalize newly acquired techniques. Two experiments using multiple baseline designs across participants assessed effectiveness of a model to promote generalization and maintenance of a specific teaching skill. In Experiment 1, preservice teachers’ maintenance of behavior deteriorated from practicum to student teaching when intervention consisted of training to criteria alone. When a programming for generalization component (program common stimuli) was added to the intervention, teachers in Experiment 2 generalized and maintained behavior across settings (student teaching to own classrooms) at a higher average than occurred during intervention.     

Analysis of individual differences in multidimensional scaling via an n-way generalization of “Eckart-Young” decomposition

An individual differences model for multidimensional scaling is outlined in which individuals are assumed differentially to weight the several dimensions of a common “psychological space”. A corresponding method of analyzing similarities data is proposed, involving a generalization of “Eckart-Young analysis” to decomposition of three-way (or higher-way) tables. In the present case this decomposition is applied to a derived three-way table of scalar products between stimuli for individuals. This analysis yields a stimulus by dimensions coordinate matrix and a subjects by dimensions matrix of weights. This method is illustrated with data on auditory stimuli and on perception of nations.     

Spatial variables and the feature-positive effect

Pigeons were trained in discriminations where S+ and S? shared common visual elements but were distinguished by the presence or absence of a visual feature. When S+ contained the distinctive feature (the feature-positive condition), the pigeons rapidly learned to withold responses to S?: The learning rate was not markedly affected by changes in the relative size of the feature and the common element. When S? contained the distinctive feature (the feature-negative condition), the pigeons learned to withhold responses to S? more rapidly when the feature was large relative to the common element than when the feature was small relative to the common element. This effect was observed when the stimuli were present at the locus of response and when the stimuli were remote from the locus of response. To explain these results, and the results of generalization tests, it was proposed that the effectiveness of the feature in suppressing responding to the common element during feature-negative training depended on the relative size of the feature and the common element.