Time-place learning by pigeons, Columba livia

In each of two experiments, 2 pigeons received discrimination training in which food reinforcement for key pecking was conditional upon both spatial and temporal cues. In Experiment 1, food was available for periods of 30 s at each of three locations (pecking keys) during trials that lasted 90 s. In Experiment 2, food was available for periods of 15 min at each of four locations (pecking keys) during a 60-min trial. In both experiments, pigeons' key pecking was jointly controlled by the spatial and temporal cues. These data, and other recent experiments, suggest that animals learn relationships between temporal and spatial cues that predict stable patterns of food availability.     

The stages of acquisition in stimulus fading

Pigeons were exposed to a stimulus fading procedure in which control of responding was transferred from red and black stimuli to lines of different angular orientation. After superimposing one line on the red stimulus and the other line on the black stimulus, the intensity of the lines was gradually increased and that of the red stimulus was gradually reduced. Probes consisting of red and line stimuli presented separately were used during the course of fading to assess control exerted by each element of the compound. As the lines were faded in, they did not acquire control of responding. As red was faded out, control of responding was acquired first by the lower intensity red stimuli in combination with the line stimulus, and finally by the angular orientation of the lines. Probes also determined the point at which the line stimuli, presented alone, would maintain a high degree of stimulus control. The results demonstrated that new stimuli in fading acquire dimensional control of responding in two sequential stages. Acquisition of stimulus control in fading was explained in terms of attenuation of stimulus blocking.     

Fetal androgens in the early treated adrenogenital syndrome of 46 XX hermaphroditism: Influence on assertive and aggressive types of behavior

Fifteen hermaphroditic females with the adrenogenital syndrome received corrective, androgen-suppressing therapy with cortisone from birth onward. They were studied psychologically in late adolescence and adulthood, with particular attention to a possible long-term effect of fetal androgenization on aggressive manifestations. No such effect was evident. The girls were tomboyish in the manner previously reported for the adrenogenital syndrome.     

Novel labels support 10-month-olds’ attention to novel objects

What is the source of the mutual exclusivity bias whereby infants map novel labels onto novel objects? In an intermodal preferential looking task, we found that novel labels support 10-month-olds’ attention to a novel object over a familiar object. In contrast, familiar labels and a neutral phrase gradually reduced attention to a novel object. Markman (1989, 1990) argued that infants must recall the name of a familiar object to exclude it as the referent of a novel label. We argue that 10-month-olds’ attention is guided by the novelty of objects and labels rather than knowledge of the names for familiar objects. Mutual exclusivity, as a language-specific bias, might emerge from a more general constraint on attention and learning.     

Bayesian parameter estimation in the Expectancy Valence model of the Iowa gambling task

The purpose of the popular Iowa gambling task is to study decision making deficits in clinical populations by mimicking real-life decision making in an experimental context. Busemeyer and Stout [Busemeyer, J. R., & Stout, J. C. (2002). A contribution of cognitive decision models to clinical assessment: Decomposing performance on the Bechara gambling task. Psychological Assessment, 14, 253-262] proposed an “Expectancy Valence” reinforcement learning model that estimates three latent components which are assumed to jointly determine choice behavior in the Iowa gambling task: weighing of wins versus losses, memory for past payoffs, and response consistency. In this article we explore the statistical properties of the Expectancy Valence model. We first demonstrate the difficulty of applying the model on the level of a single participant, we then propose and implement a Bayesian hierarchical estimation procedure to coherently combine information from different participants, and we finally apply the Bayesian estimation procedure to data from an experiment designed to provide a test of specific influence.     

Learned preference for a hedonically negative flavor is observed after pairings with positive post-ingestion consequences rather than with a palatable flavor

In two experiments, thirsty rats consumed a compound of sucrose and a non-preferred flavor. In Experiment 1, a conditioned preference was observed in the experimental group when animals were tested both thirsty and hungry, but not when they were tested just thirsty. Animals in the control group, which experienced the flavor and the sucrose unpaired, never showed a preference. Experiment 2 replicated the absence of a preference in the experimental group when rats were tested thirsty, but provided evidence that a flavor-taste association had been formed during training. After conditioning, sucrose was paired with LiCl in group Dev whereas it was unpaired in group NonDev. The sucrose devaluation produced a decrease in CS preference in group Dev, and an increment in group NonDev. Taken together, these results show that preference for a non-preferred flavor can be readily observed after pairings with the positive consequences of the US (calories or absence of an expected illness) rather than with a palatable flavor.     

CBL、PBL及Seminar结合的立体教学模式的应用和思考——临床医学八年制呼吸科床旁教学实践中的应用

临床医学八年制内科学床旁教学应用传统的教学模式及基于案例的学习（CBL）单一教学方法难以满足教学要求.将CBL与基于问题的学习（PBL）及研讨会（Seminar）结合的立体教学模式应用于呼吸科的床旁教学实践中,激发了学生学习的积极性、创新性,培养了学生良好的团队合作精神和临床思维模式,提高了学生们解决临床问题的能力,并能加深师生互动交流,达到教学相长的目的.     

Learning new vocabulary during childhood: Effects of semantic training on lexical consolidation and integration

Research suggests that word learning is an extended process, with offline consolidation crucial for the strengthening of new lexical representations and their integration with existing lexical knowledge (as measured by engagement in lexical competition). This supports a dual memory systems account, in which new information is initially sparsely encoded separately from existing knowledge and integrated with long-term memory over time. However, previous studies of this type exploited unnatural learning contexts, involving fictitious words in the absence of word meaning. In this study, 5- to 9-year-old children learned real science words (e.g., hippocampus) with or without semantic information. Children in both groups were slower to detect pauses in familiar competitor words (e.g., hippopotamus) relative to control words 24 h after training but not immediately, confirming that offline consolidation is required before new words are integrated with the lexicon and engage in lexical competition. Children recalled more new words 24 h after training than immediately (with similar improvements shown for the recall and recognition of new word meanings); however, children who were exposed to the meanings during training showed further improvements in recall after 1 week and outperformed children who were not exposed to meanings. These findings support the dual memory systems account of vocabulary acquisition and suggest that the association of a new phonological form with semantic information is critical for the development of stable lexical representations.     

Short-term memory for serial order supports vocabulary development: New evidence from a novel word learning paradigm

Although recent studies suggest a strong association between short-term memory (STM) for serial order and lexical development, the precise mechanisms linking the two domains remain to be determined. This study explored the nature of these mechanisms via a microanalysis of performance on serial order STM and novel word learning tasks. In the experiment, 6- and 7-year-old children were administered tasks maximizing STM for either item or serial order information as well as paired-associate learning tasks involving the learning of novel words, visual symbols, or familiar word pair associations. Learning abilities for novel words were specifically predicted by serial order STM abilities. A measure estimating the precision of serial order coding predicted the rate of correct repetitions and the rate of phoneme migration errors during the novel word learning process. In line with recent theoretical accounts, these results suggest that serial order STM supports vocabulary development via ordered and detailed reactivation of the novel phonological sequences that characterize new words.     

Whom do children copy? Model-based biases in social learning

This review investigates the presence of young children’s model-based cultural transmission biases in social learning, arguing that such biases are adaptive and flexible. Section 1 offers five propositions regarding the presence and direction of model-based transmission biases in young children’s copying of a model. Section 2 discusses the cognitive abilities required for differing model-based biases and tracks their development in early childhood. Section 3 suggests future areas of research including considering the social aspect of model-based biases and understanding their use within a comparative perspective.