Honeybees generalize among pollen scents from plants flowering in the same seasonal period.

When honey bees (Apis mellifera) feed on flowers, they extend their proboscis to absorb the nectar, i.e. they perform the proboscis extension response (PER). The presence of pollen and/or nectar can be associated with odors, colors or visual patterns, which allows honey bees to recognize food sources in the environment. Honey bees can associate similar, though different, stimuli with the presence of food; i.e. honey bees discriminate and generalize among stimuli. Here, we evaluated generalization among pollen scents from six different plant species. Experiments were based on the PER conditioning protocol over two phases: (1) conditioning, in which honey bees associated the scent of each pollen type with sucrose, and (2) test, in which honey bees were presented with a novel scent, to evaluate generalization. Generalization was evinced by honey bees extending their proboscis to a novel scent. The level of PER increased over the course of the conditioning phase for all pollen scents. Honey bees generalized pollen from Pyracantha coccinea and from Hypochaeris radicata These two plants have different amounts of protein and are not taxonomically related. We observed that the flowering period influences the olfactory perceptual similarity and we suggest that both pollen types may share volatile compounds that play key roles in perception. Our results highlight the importance of analyzing the implications of the generalization between pollen types of different nutritional quality. Such studies could provide valuable information for beekeepers and agricultural producers, as the generalization of a higher quality pollen can benefit hive development, and increase pollination and honey production.

Generalização estrutural a partir do tratamento por diferentes modelos de oposições / Structural generalization after treatment based on different oppositions approaches

Este trabalho teve como objetivo analisar a generalização estrutural (a itens não utilizados no tratamento, para outras posições na palavra, dentro de uma classe de sons e para outras classes de sons) em três diferentes modelos de abordagem contrastiva, considerando-se a gravidade do desvio fonológico. A amostra constituiu-se de nove sujeitos com desvio fonológico, com idades entre 4 anos e 2 meses e 6 anos e 6 meses. Todos foram avaliados, antes e após a terapia fonológica. Foram estabelecidos três grupos para o tratamento, todos constituídos por três sujeitos; em cada um havia um representante com desvio grave, moderado-grave e médio-moderado. Cada grupo foi tratado por um modelo diferente - Oposições Mínimas, Oposições Máximas/Empty Set e Oposições Múltiplas. A análise estatística dos resultados foi feita mediante comparação entre os modelos terapêuticos e a gravidade do desvio fonológico, utilizando-se os tipos de generalização. Verificou-se a ocorrência dos diferentes tipos de generalização em todos os grupos estudados, entretanto não houve diferença entre eles. Os três modelos de terapia aplicados favoreceram a ocorrência de generalização estrutural nas três diferentes gravidades do desvio, demonstrando que os modelos de abordagem contrastiva são eficazes no tratamento do desvio fonológico.

This study had the aim to analyze structural generalization (to untreated words, to other word positions, across and within sound classes) in three different models of contrastive approach, based on the severity of phonological disorder. The sample comprised nine subjects with phonological disorders with ages between 4 years and 2 months and 6 years and 6 months. All subjects were assessed before and after phonological therapy. Three groups with three subjects each were established for treatment; each group had one subject with severe, moderate-severe and mild-moderate disorder, and each was treated by a different model - Minimal Oppositions, Maximal Oppositions/Empty Set, and Multiple Oppositions. Statistical analysis compared therapeutic models and the severity of phonological disorders, using the types of generalization. It was verified the occurrence of different types of generalization across all groups, however, there was no statistical difference between them. All three models of intervention favored the occurrence of structural generalization in the three different severities of disorders, demonstrating that contrastive approach models are effective in the treatment of phonological disorders.

Rapid eye-fixation training without eyetracking.

Maintenance of stable central eye fixation is crucial for a variety of behavioral, electrophysiological, and neuroimaging experiments. Naive observers in these experiments are not typically accustomed to fixating, either requiring the use of cumbersome and costly eyetracking or producing confounds in results. We devised a flicker display that produced an easily detectable visual phenomenon whenever the eyes moved. A few minutes of training using this display dramatically improved the accuracy of eye fixation while observers performed a demanding spatial attention cuing task. The same amount of training using control displays did not produce significant fixation improvements, and some observers consistently made eye movements to the peripheral attention cue, contaminating the cuing effect. Our results indicate that (1) eye fixation can be rapidly improved in naive observers by providing real-time feedback about eye movements, and (2) our simple flicker technique provides an easy and effective method for providing this feedback.

Terapia fonológica: a generalização a itens não utilizados no tratamento (outras palavras) / Phonological therapy: the generalization to non used items during treatment (other words)

OBJETIVO: verificar a generalização a itens não utilizados no tratamento (outras palavras) obtida em três modelos de terapia em sujeitos com diferentes graus de gravidade do desvio fonológico. MÉTODOS: o grupo pesquisado foi constituído por 21 sujeitos com desvio fonológico, 11 do sexo masculino e 10 do feminino, com média de idade no início do tratamento de 5:7 anos. Os dados da fala foram analisados por meio da avaliação fonológica. Após a realização da análise contrastiva, foi calculado o Percentual de Consoantes Correta (Shriberg e Kwiatkowski, 1982) e os sujeitos foram classificados nos diferentes graus de gravidade do desvio fonológico em: grave; moderado-grave; médio-moderado; e médio. Seis sujeitos foram submetidos ao Modelo de Ciclos Modificado, oito ao Modelo ABAB-Retirada e Provas Múltiplas, e sete ao Modelo Oposições Máximas Modificado. Fez-se uma comparação da generalização a itens não utilizados no tratamento (outras palavras) entre os três modelos de terapia para cada grau de gravidade do desvio fonológico. RESULTADOS: dos sujeitos com desvio grave, moderado-grave e médio, três apresentaram maiores generalizações a outras palavras, todos submetidos ao Modelo ABAB-Retirada e Provas Múltiplas. Dos sujeitos com desvio médio-moderado, foram os tratados pelo Modelo de Oposições Máximas Modificado que mais generalizaram. CONCLUSÃO: todos os sujeitos apresentaram evoluções no sistema fonológico e, quanto à generalização a itens utilizados no tratamento (outras palavras) observou-se maior percentual de generalização nos modelos ABAB-Retirada e Provas Múltiplas e Oposições Máximas Modificado.

PURPOSE: to check the generalization to non used items during treatment (other words) obtained in the three different models of therapy in subjects with different degrees of phonological disorder severity. METHODS: the studied group was composed by twenty-one subjects, eleven males and ten females, with average age when of the beginning of treatment 5:7. Speech data were analyzed through the performance of the phonological assessment. After the phonological assessment, the percentage of correct consonants proposed by Shriberg & Kwiatkowski (1982) was calculated and the subjects were then classified in the degrees of phonological disorder severity: severe, moderate-severe, mild-moderate and mild disorder. Six subjects were submitted to the Modified Cycles Model, eight to the ABAB-Withdrawal and Multiple Probes Model and seven to the Modified Maximum Opposition Model. A comparison was made on the generalization to non used items during treatment (other words) among three models of therapy within each degree of phonological disorder severity. RESULTS: Among the subjects with severe, moderate-severe and mild disorder, three subjects that presented the major generalization to non used items during treatment, all treated with ABAB-Withdrawal and Multiple Probes Model. Of the subjects with mild-moderate disorder, were treated with the Modified Maximum Opposition Model those that showed the major generalization. CONCLUSION: all the subjects showed gains in the phonological system and as for the generalization to non used items during treatment (other words), but ABAB-Withdrawal and Multiple Probes and Modified Maximum Opposition Models were more effective.

Memoria operativa y circuitos corticales / Working memory and cortical pathways

En el presente artículo se expone una revisión del concepto “memoria operativa”, teniendo en cuenta dos aproximaciones principales. Por una parte la psicología cognitiva, particularmente en el campo de la memoria y el aprendizaje; mientras que por otra parte, se presentan algunos aspectos del aporte de las neurociencias, tanto en lo relacionado con fenómenos clínicos como experimentales. Se hace referencia al síndrome prefrontal desde una perspectiva histórica, se consideran igualmente algunos estudios electrofisiológicos, de imagen funcional, así como los relacionados con ablaciones corticales. Se presenta al final, un modelo de “circuitería” asociada con el proceso de la memoria operativa, en el cual se consideran cinco circuitos básicos: tanto los que se establecen entre regiones corticales, como entre estas y estructuras subcorticales

Inundaciones: El gobierno de Bolivia solicitó ayuda internacional / The government of Bolivia requests international assistance

Luego de las inundaciones y deslizamientos de tierras de Marzo de 2000 que afectaron a 1.200 familias y dañaron cientos de kilómetros cuadrados de cultivos en los departamentos al este de Bolivia, este año las fuertes lluvias causaron inundaciones y deslizamientos en las regiones al occidente y norte del país.

El estrés psicosocial y su relación con las respuestas de enfrentamiento y el malestar emocional en una muestra representativa de adolescentes al sur de la ciudad de México: análisis según su nivel socioeconómico / Psychosocial stress and its relation with coping responses and emotional destress in a representative sample of adolescents of Mexico City. An analysis according to their socioeconomic level

Entendido como un proceso dinámico y multifactorial, la inter-relación del estrés psicosocial-respuestas de enfrentamiento-malestar emocional se ha configurado para delimitar modelos conceptuales ampliamente reconocidos (Cervantes y Castro, 1985; Moos, 1984, Lazarus, 1990). A partir de tales planteamientos, se llevó a cabo una investigación para indagar la educación de tal inter-relación en adolescentes mexicanos. Es así que el objetivo de este trabajo es presentar la configuración resultante del interjuego del estrés psicosocial- respuestas de enfrentamiento-malestar emocional, a fin de identificar las diferencias según el nivel socioeconómico (NSE): bajo y medio. Las áreas evaluadas potencialmente estresantes para la población abordada fueron: familiar, social (mejor amigo) y sexualidad. Las escalas de Estrés Psicosocial y de Respuestas de Enfrentamiento se construyeron a partir de experiencias anteriores y de un estudio piloto (N = 100) para esta investigación en particular. El malestar emocional evaluado se refirió a la sintomatología depresiva (CES_D, Radloff, 1977) y a la ideación suicida (Roberts, 1980). Todas las escalas aplicadas mostraron su adecuación (Consistencia interna y estructura factorial) en la población estudiada, que fue una muestra representativa de adolescentes que residían en la Delegación política de Coyoacán, al sur de la ciudad de México, en 1995. El procedimiento de muestreo fue riguroso para representar por igual a los hombres y mujeres de NSE bajo y medio de 13 a 18 años de edad. Se utilizó diseño de muestreo estratificado, con un esquema de selección de conglomerados en tres etapas: 1) las áreas geoestadísticas básicas (AGEB), clasificadas según el NSE bajo y medio; 2) las manzanas o grupos de ellas en cada AGEB; y 3) las viviendas en que habitaban los adolescentes. El diseño del estudio fue ex-post-facto y transversal. Los datos se obtuvieron en los hogares o en sus cercanías, previo consentimiento informado de los padres y de los adolescentes. La muestra total quedó integrada por 800 adolescentes. Se decidió probar los planteamientos teóricos por medio de modelos FASEM (Factor Analysis Structural Equation Models) para evaluar el ajuste del modelo conceptual a los datos obtenidos e indagar cuáles aspectos del comportamiento de las variables y relaciones planteadas en el modelo serían diferentes entre los adolescentes de NSE bajo medio. El análisis se hizo con el Programa EQS, versión 5.4 (Bentler, 1995)...

Facilitation of memory by peripheral administration of substance P.

This report summarizes a recent series of experiments dealing with the effect of peripheral (i.p.) administration of SP on the learning of avoidance and habituation tasks. In summary, the results from these studies show that peripheral post-training SP administration in rats enhances memory in a dose- and time-dependent way. The effect of substance P on retention was observed across tasks with different response requirements and in the absence of explicit punishment. The memory-enhancing effects are long-lasting, until 21 days post-training, and are mediated, at least in part, via interactions with the endogenous opioid system. The mnemotropic effects of peripherally administered SP are sensitive to the functional integrity of the vagus, suggesting that the vagus nerve may be one pathway by which systemic SP influences memory storage processes in the brain. Furthermore, the data indicated that these effects seemed to be encoded by different SP sequences, the N-terminal SP1-7, but not the C-terminal hepta- and hexapeptide sequences being responsible for the memory-promoting effects. Taken together, these studies strongly suggest that SP may be considered to have memory-promoting effects.