Categorical Discrimination of Human Facial Expressions by Pigeons: A Test of the Linear Feature Model

Pigeons were trained to discriminate human facial expressions, happiness and anger, in a go/ no-go discrimination procedure. Five pigeons learned to discriminate photographs of the happy and angry faces of 25 different people and showed high levels of transfer to novel faces expressing the training emotions. The pigeons directed their pecks predominantly to the mouth, eyes, or the area between these features. The pigeons were then tested with familiar stimuli in which the upper and lower parts of the face were manipulated separately by substitution or removal of facial features ('eyes-and-eyebrows' and 'mouth'). It was shown that the salience of particular features differed considerably among the birds, but that a linear feature model adequately accounted for discriminative performance of the birds with these stimuli. Furthermore, the discrimination was maintained when these features were inverted. Thus, the so-called Thatcher illusion did not occur. It is suggested that the discrimination is based not on a feature configuration or perceptual gestalt but on an additive integration of individual features.     

Landmark Discrimination Learning in the Dog

Allocentric spatial memory was studied in dogs of varying ages and sources using a landmark discrimination task. The primary goal of this study was to develop a protocol to test landmark discrimination learning in the dog. Using a modified version of a landmark test developed for use in monkeys, we successfully trained dogs to make a spatial discrimination on the basis of the position of a visual landmark relative to two identical discriminanda. Task performance decreased, however, as the distance between the landmark and the “discriminandum” was increased. A subgroup of these dogs was also tested on a delayed nonmatching to position spatial memory task (DNMP), which relies on egocentric spatial cues. These findings suggest that dogs can acquire both allocentric and egocentric spatial tasks. These data provide a useful tool for evaluating the ability of canines to use allocentric cues in spatial learning.     

Observational Learning in Pigeons: The effects of Model Proficiency on Observer Performance

Observational learning of a successive visual discrimination problem by pigeons was studied using conspecifics as models performing at proficient or at nonproficient levels. During the observational period, observers were confined without response opportunity and were subsequently trained in the model's discriminative task. Significantly better performance in subsequent learning was found for observers of nonproficient models. In contrast, no significant differences in learning of the visual discrimination task were found between pigeons that observed proficient models and pigeons that had undergone only confinement in the observation apparatus or those trained without prior observation or confinement experience. The apparent paradox of less proficient models producing better learners may be related to the consequences of observing additional negative-stimulus responding per se or to observation of models' behavior changing from less proficient to more proficient with consequent improvement in reinforcement opportunity.     

Differential Reinforcement in Simple Discrimination Learning in 10- to 20-Month-Old Toddlers

The Psychological Record - The present study examined two procedures for teaching simple discrimination to six toddlers aged 10- to 20-months. A pair of toys was displayed in the windows of an...     

Observational Learning and the Role of Confinement in Pigeons: Suppression of Learning as a Function of Observing the Performance of a Conspecific

Observational learning of a successive discrimination problem by pigeons was studied using conspecifics as models responding for either contingent or noncontingent reinforcement. We found that observation of these models was associated with poorer performance on subsequent testing than was shown by a control group that learned without first observing conspecifics' performance. No significant difference was found between subjects without observational experience and another control group that was confined in the observation apparatus and observed an empty chamber only.     

The Effects of Hippocampal and Area Parahippocampalis Lesions in Pigeons: II. Concurrent Discrimination and Spatial Memory

Two experiments were conducted to examine the effects of bilateral hippocampus (Hp) and area parahippocampalis (APH) lesions in pigeons on the acquisition of a visual and spatial task. In Experiment 1, pigeons were trained on three successive six-pair concurrent discrimination tasks, each using a novel set of stimuli. There was no difference between control unoperated pigeons and Hp-APH pigeons in terms of the number of sessions required to learn either the first, second, or third concurrent discrimination task. In Experiment 2, the same pigeons were trained on an open-field spatial task similar in many ways to the radial-arm maze task used with rats. In contrast to the absence of impairments on the visual concurrent discrimination task, pigeons with Hp-APH lesions were severely impaired on the acquisition of the spatial task. These findings support the view that the Hp-APH in pigeons is important for the processing of spatial, rather than visual information.     

学业不良的相对性涵义及测定的实证研究

本文在介绍和分析了国内外关于学业不良概念以及在心理学限定方面差异的基础上,就学业不良的相对性涵义进行了探讨,并对我国相对性学业不良者的测定进行了实证研究。其主要涉及到关于学业不良的相对性涵义、美国与我国对相对性学业不良者实际心理限定方面的差异;研究了“智力-成绩差距”的测定问题,包括客观判定标准值、自我主观认知因素的测定和教师的观察判定。     

Net Amount of Food Affects Autoshaped Response Rate, Response Latency, and Gape Amplitude in Pigeons

The contribution of net amount of food to conditioned response strength and topography was assessed in four pigeons under autoshaping contingencies. In each session, under one baseline phase and three replication phases, three trial types were presented sequentially: One conditioned stimulus (keylight) signaled one small pellet, another signaled one large pellet, and a third signaled seven small pellets which were weight-matched to one large pellet. Five dependent variables were response rates and latencies based on the occurrence of both keyswitch closures and gapes (beak openings) and gape amplitudes. In result, net amount of food, not pellet diameter or number, affected all dependent variables. Notably, gape amplitudes elicited by the seven-small pellet keylights were larger than the gape amplutides elicited by the one-small pellet keylights even though the gape amplitudes elicited by both unconditioned stimuli (one or seven pellets) were equally small. This mismatch between conditioned and unconditioned responses is incompatible with stimulus substitution accounts but is compatible with an associative strength account. Furthermore, the changes in the dependent variables were most likely determined by Pavlovian and not by inadvertent operant contingencies. The findings demonstrate that an analysis of classical conditioning benefits from the inclusion of topographical measures.     

光栅朝向分辨学习中存在关于45°对角线对称的镜像迁

采用光栅朝向分辨任务来探讨视知觉学习中是否存在关于45°对角线对称的镜像迁移现象。训练被试分辨15°或75°朝向3或5天,每天约1小时,训练前后测量15°、75°、45°朝向的分辨阈值。通过训练,训练朝向（15°或75°）的阈值下降,该学习效应没有迁移至45°朝向,但基本迁移到关于45°对称的朝向（75°或15°）上。这提示,视知觉学习可能发生在中间视皮层,该皮层同时具有一定的朝向特异性和关于45°对角线对称的镜像迁移性     

光栅朝向分辨学习中存在关于45°对角线对称的镜像迁移

采用光栅朝向分辨任务来探讨视知觉学习中是否存在关于45°对角线对称的镜像迁移现象.训练被试分辨15°或75°朝向3或5d,每天约1h,训练前后测量15°、75°、45°朝向的分辨阈值.通过训练,训练朝向(15°或75°)的阈值下降,该学习效应没有迁移至45°朝向,但基本迁移到关于45°对称的朝向(75°或15°)上.这提示,视知觉学习可能发生在中间视皮层,该皮层同时具有一定的朝向特异性和关于45°对角线对称的镜像迁移性.     

Emergent Simple Discrimination via Transfer from Differentially Reinforced S+ Stimuli: A Further Test of the Stimulus-Response Interaction Model

This study examined emergent form discrimination through contiguity of the forms (B stimuli) with colours (A stimuli) associated with different magnitudes of reinforcement. In Experiment 1, children were trained on two colour discriminations. In both, the colour stimuli had the same form: A1B1/A2B1 and A3B1/A2B1. Responding to A1/B1 was followed by three units of reinforcement, to A3B1 by one unit of reinforcement, and to A2B1 by no reinforcement. There followed five tests in which stimuli were presented without programmed consequences. These assessed: (1) the maintenance of accurate performance on the training tasks; (2) S+ preference (A1B1/A3B1); (3) stimulus generalization (A1B2/A2B3, A3B4/A2B5); (4) S+ preference again (A1B6/A3B6); and (5) transfer from the S+ colours to the forms (A4B2/A4B4). On the final test, seven of the eight subjects selected A4B2. Experiment 2 demonstrated that a preference for A4B2 also occurred when the S+ preference tests were omitted. This preference was also found when the total amounts of reinforcement associated with the S+ colours (A1 and A3) were the same (Experiment 3). These findings: (a) indicate that children can acquire new discriminations under non-reinforced conditions through contiguity with differentially reinforced S+ stimuli; (b) support the Stimulus-Response Interaction model (Smeets, 1993) for specifying transfer.     

Long-Term Retention of Olfactory Discrimination Learning Set in Rats

The Psychological Record - Six male Sprague-Dawley rats were used to examine the long-term retention of an olfactory discrimination learning set. Rats were trained on 30 odor-unique, 5-trial...     

Learning Behavioral Repertoires with Different Consequences Hinders the Interconnection of These Repertoires in Pigeons in the Box Displacement Test

The Psychological Record - The interconnection of repertoires is a behavioral process related to problem solving and creativity. Experiments on this topic have mostly used a single reinforcer type...     

How Inspecting a Picture Affects Processing of Text in Multimedia Learning

We investigated how a picture fosters learning from text, both with self‐paced presentation and with short presentation before text. In an experiment, participants (N = 114) learned about the structure and functioning of a pulley system in one of six conditions: text only, picture presentation for 150 milliseconds, 600 milliseconds, or 2 seconds, or self‐paced before text, or self‐paced concurrent presentation of text and picture. Presenting the picture for self‐paced study time, both before and concurrently with text, fostered recall and comprehension and sped up text processing compared with presenting text only. Moreover, even inspecting the picture for only 600 milliseconds or 2 seconds improved comprehension and yielded faster reading of subsequent text about the spatial structure of the system compared with text only. These findings suggest that pictures, even if attended for a short time only, may yield a spatial mental scaffold that allows for the integration with verbal information, thereby fostering comprehension. Copyright © 2013 John Wiley & Sons, Ltd.     

Motivating Operations Affect Stimulus Control: A Largely Overlooked Phenomenon in Discrimination Learning

Several recent studies have explored what Michael (e.g., 1982) termed the value-altering effect and the behavior-altering effect of motivating operations. One aspect of the behavior-altering effect that has garnered no recent attention involves changes in stimulus control produced by motivating operations. To call attention to this aspect of the behavior-altering effect, we herein review 11 studies that are concerned with the influence of varying levels of food or water deprivation on stimulus generalization. These studies suggest that motivating operations influence stimulus control (a) by changing the evocative strength of not just an established discriminative stimulus, but also of stimuli that are physically similar to it; (b) by changing the range of stimuli that evoke the operant in question; and (c) by exerting these effects in a graded fashion. These findings are potentially of conceptual and applied significance, and it appears that further research examining how motivating operations alter stimulus control, including some studies suggested herein, is warranted.     

Pigeons play the percentages: computation of probability in a bird

The ability to compute probability, previously shown in nonverbal infants, apes, and monkeys, was examined in three experiments with pigeons. After responding to individually presented keys in an operant chamber that delivered reinforcement with varying probabilities, pigeons chose between these keys on probe trials. Pigeons strongly preferred a 75% reinforced key over a 25% reinforced key, even when the total number of reinforcers obtained on each key was equated. When both keys delivered 50% reinforcement, pigeons showed indifference between them, even though three times more reinforcers were obtained on one key than on the other. It is suggested that computation of probability may be common to many classes of animals and may be driven by the need to forage successfully for nutritional food items, mates, and areas with a low density of predators.     

The Seller's Sense: Buying–Selling Perspective Affects the Sensitivity to Expected Value Differences

Previous work comparing pricing decisions by buyers and sellers has primarily focused on the endowment effect, the phenomenon that selling prices exceed buying prices. Here, we examine whether pricing decisions by buyers and sellers also vary in sensitivity to differences between objects' expected values (EVs). Both a loss‐aversion account (which posits that losses are weighted more heavily than gains) and a loss‐attention account (which posits increased attention to a task when it involves possible losses) predict that pricing decisions by sellers should exhibit higher sensitivity. The latter, however, additionally predicts that this pattern should only emerge under certain conditions. In studies 1 and 2, we reanalyzed two published datasets in which participants priced monetary lotteries as sellers or buyers. It emerged that sellers showed greater EV sensitivity (defined as the rank correlation between the set price for each lottery and its EV) except in a condition with an extended deliberation time of 15 seconds. In study 3, the buyer–seller difference in EV sensitivity was replicated even when the pricing task was presented repeatedly, while in study 4, it was eliminated when buying and selling trials were randomly mixed. The reduction of the “seller's sense” in long deliberation and mixed trials settings supports an attentional resource‐based account of the differences between sellers and buyers in their EV sensitivity. Copyright © 2016 John Wiley & Sons, Ltd.     

Learning What is Essential: Relative and Absolute Changes in Children's Beliefs about the Heritability of Ethnicity

There are conflicting findings regarding the development of essentialist beliefs about social categories. The present studies address these findings by differentiating between the developments of the relative versus absolute essentialist status of categories. Participants were Israeli Secular Jewish and Muslim Arab kindergarteners, second graders, and sixth graders. Study 1 asked children which among alternative properties of a parent was most likely to transfer to a child. Findings showed that while kindergarteners did not systematically discriminate among properties, second and sixth graders privileged ethnicity. Study 2 asked children whether membership in various social categories was biologically or environmentally determined. Findings showed that kindergarteners and second graders, but not sixth graders, believed ethnicity to be biologically inherited. These results are discussed vis-à-vis different theories about the origins of social essentialism.