Cooperative responding in rats: II. Performance on fixed-ratio schedules of mutual reinforcement.

Coordinated responses of 5 dyads of rats were investigated under fixed-ratio (FR) schedules of mutual water reinforcement. Coordinated responding was defined as 2 consecutive lever-presses, 1 from each of 2 rats, occurring <.5 s apart. In the FR schedules, each coordinated episode was defined as 1 response in the FR sequence. The size of FR schedules was parametrically manipulated assuming the values of FR 1, 6, 12, 18, 24, 30, 50, and 9, in this order. Each FR remained in effect until responding reached stability. Under all conditions, pairs of rats received access to water simultaneously (mutual reinforcement). Rates and proportions of coordinated responding showed a bitonic inverted U-shaped function of ratio size. Postreinforcement pauses increased systematically as the interreinforcement interval increased. Local rates and proportions increased as a function of response location within ratios. Results of a control condition with relaxed temporal constraints for mutual reinforcement showed decreases in rates and proportion of coordinated responses, suggesting that the coordinated responses were controlled by the mutual reinforcement contingencies. The present experiment showed that coordinated responding is quantitatively affected by 3 properties of FR schedules: response requirement, reinforcement rates, and proximity to reinforcement.

Simple discrimination in stingless bees (Melipona quadrifasciata): Probing for select- and reject-stimulus control.

Simple and conditional discrimination training may produce various types of controlling relations. Responses may be controlled primarily by the positive stimulus (select-control relation) or by the negative stimulus (reject-control relation; the subject excludes the negative stimulus and chooses the positive). Bees learn to respond in simple and conditional discriminations. However, no study has searched for reject-control responding in Melipona bees. We trained Melipona quadrifasciata on a simple discrimination task (S+ vs. S-; e.g., blue vs. yellow) and then probed for stimulus control with two types of probe trials, S+ versus a new stimulus (Select-control probes) and S- versus a new stimulus (Reject-control probes). For Group Different, a new-stimulus color (e.g., white) was used in one type of probe and another color (e.g., black) was used in the other type. For Group Same, a single new-stimulus color was used in both types of probes. On Select probes, the bees always preferred S+ to the new stimulus. On Reject probes, results were mixed. Depending on the colors used in training and probing, bees responded to both stimuli, and even preferred the S-. The data suggest no control by the negative function of the S- and support the select-stimulus control hypothesis of responding.

Cooperative responding in rats maintained by fixed- and variable-ratio schedules.

The present study investigated the effects of fixed-ratio (FR) and variable-ratio (VR) reinforcement schedules on patterns of cooperative responding in pairs of rats. Experiment 1 arranged FR 1, FR 10, and VR 10 schedules to establish cooperative responding (water delivery depended on the joint responding of two rats). Cooperative response rates and proportions were higher under intermittent schedules than under continuous reinforcement. The FR 10 schedule generated a break-and-run pattern, whereas the VR 10 schedule generated a relatively high and constant rate pattern. Experiment 2 evaluated the effects of parametric manipulations of FR and VR schedules on cooperative responding. Rates and proportions of cooperative responding generally increased between ratio sizes of 1 and 5 but showed no consistent trend as the ratio increased from 5 to 10. Experiment 3 contrasted cooperative responding between an FR6 schedule and a yoked control schedule. Coordinated behavior occurred at a higher rate under the former schedule. The present study showed that external consequences and the schedules under which the delivery of these consequences are based, select patterns of coordinated behavior.

Análise dos erros apresentados por adultos iletrados ao longo de um programa informatizado de ensino de leitura e escrita / Analysis of errors presented by illiterate adults throughout a computerized program to teach reading and writing skills / Análisis de errores presentados por adultos iletrados a lo largo de un programa computarizado de enseñanza de lectura y escritura

A tipologia de erros apresentados por crianças na aquisição de leitura e escrita tem sido amplamente explorada. A análise de erros permite inferir fontes de controle do comportamento ao longo da aprendizagem, sendo por isso um importante instrumento para o aperfeiçoamento de programas de ensino. No entanto, poucos estudos têm explorado a tipologia de erros apresentados por adultos iletrados. Este é um estudo descritivo que teve como objetivo identificar/analisar os erros cometidos por participantes adultos durante o processo de aprendizagem da leitura e escrita, submetidos a um programa informatizado de ensino, visando verificar a adequação do programa ou a necessidade de procedimentos específicos para esta população. Quinze adultos passaram individualmente pelo programa, constituído por uma sequência de passos de ensino e avaliação (pré e póstestes e testes intermediários). Os erros foram categorizados e analisados com base nas categorias descritas na literatura e categorias novas, criadas especificamente para este trabalho. Os dados mostraram grande concentração de erros em algumas categorias, principalmente para o primeiro módulo de ensino, com indicação parcial de especificidade de tipologia de erros para a população em foco. Os participantes também mostraram dificuldade na escrita (ditado por construção), indicando a necessidade de aperfeiçoamento do programa quando utilizado na alfabetização de adultos.

La tipología de los errores presentados por los niños en la adquisición de la lectura y la escritura ha sido ampliamente examinada. El análisis de errores permite inferir fuentes de control del comportamiento durante el aprendizaje, siendo así una herramienta importante para perfeccionar los programas de enseñanza. Sin embargo, pocos estudios han explorado los tipos de errores cometidos por adultos iletrados. Este es un estudio descriptivo que tuvo como objetivo identificar y analizar los errores cometidos por adultos que están aprendiendo a leer y escribir, a partir de un programa de enseñanza computarizado, con el fin de verificar la adecuación del programa a la necesidad de desarrollar procedimientos específicos para esta población. Quince adultos se sometieron individualmente al programa, el cual se compone de una secuencia de pasos de enseñanza y evaluación (pre y postpruebas y exámenes intermedios). Los errores fueron clasificados y analizados con referencia a las categorías descritas en la literatura y algunas nuevas creadas específicamente para este trabajo. Los datos muestran alta concentración de errores en algunas categorías, especialmente para el primer módulo de enseñanza, con indicación parcial de especificidad de los tipos de errores para la población objeto de estudio. Los participantes también presentaron dificultades en la tarea de dictado por construcción, lo cual indica la necesidad de perfeccionamiento del programa cuando es utilizado en la alfabetización de adultos.

The typology of errors presented by children in the acquisition of reading and writing has been widely explored. Error analyses allow inferring sources of behavior control throughout the learning process and are an important tool for improving programs that teach reading and writing. Nevertheless, few studies have explored the types of errors made by illiterate adults. This is a descriptive study aiming to identify and analyze the errors made by adults participating in the process of learning to read and write using a computerized teaching program. The purpose was to evaluate the adequacy of the program and to point out whether there is a need to develop specific procedures for this population. Fifteen adults were individually submitted to the program, which comprises a sequence of teaching steps and assessments (pre and post-tests and intermediate tests). Errors made by the students were categorized and analyzed according to categories described in the literature as well as new ones created specifically for this study. The data show a high concentration of errors in some categories, particularly for the first teaching module, with partial indication of error type specificity for the population in focus. This study also shows the participants' difficulties in writing (construction spelling task), requiring improvement of the computerized program when applied to adult literacy.

A comparative study of relational learning capacity in honeybees (Apis mellifera) and stingless bees (Melipona rufiventris).

BACKGROUND: Learning of arbitrary relations is the capacity to acquire knowledge about associations between events or stimuli that do not share any similarities, and use this knowledge to make behavioural choices. This capacity is well documented in humans and vertebrates, and there is some evidence it exists in the honeybee (Apis mellifera). However, little is known about whether the ability for relational learning extends to other invertebrates, although many insects have been shown to possess excellent learning capacities in spite of their small brains. METHODOLOGY/PRINCIPAL FINDINGS: Using a symbolic matching-to-sample procedure, we show that the honeybee Apis mellifera rapidly learns arbitrary relations between colours and patterns, reaching 68.2% correct choice for pattern-colour relations and 73.3% for colour-pattern relations. However, Apis mellifera does not transfer this knowledge to the symmetrical relations when the stimulus order is reversed. A second bee species, the stingless bee Melipona rufiventris from Brazil, seems unable to learn the same arbitrary relations between colours and patterns, although it exhibits excellent discrimination learning. CONCLUSIONS/SIGNIFICANCE: Our results confirm that the capacity for learning arbitrary relations is not limited to vertebrates, but even insects with small brains can perform this learning task. Interestingly, it seems to be a species-specific ability. The disparity in relational learning performance between the two bee species we tested may be linked to their specific foraging and recruitment strategies, which evolved in adaptation to different environments.

Recombinative reading derived from pseudoword instruction in a miniature linguistic system.

A miniature linguistic system was used to study acquisition of recombinative symbolic behavior. Three studies evaluated the teaching conditions of conditional discriminations with printed and spoken pseudowords that could potentially generate recombinative reading. Fifty-four college students across all studies learned to match 12 printed pseudowords to 12 spoken pseudowords. Some also matched pictures to the same spoken words. Each two-syllable pseudoword was formed by symbols from an arbitrarily created alphabet composed of four vowels and four consonants. Letters had univocal correspondence with phonemes. Recombinative receptive reading, comprehensive reading, and textual responding to pseudowords were periodically assessed. Experiment 1 (n  =  20) showed that recombinative reading increased as the number of trained words composed of the same symbols increased. Experiment 2 (n  =  14) showed that overtraining the same two words did not produce recombinative reading for most participants. Experiment 3 (n  =  20), in which training with pictures was omitted, showed that elemental control by within-syllable units can develop even when the trained pseudowords are meaningless (not related to pictures). The present results support the utility of the miniature linguistic system methodology for identifying and controlling environmental determinants of rudimentary reading skills.