Implicit word learning benefits from semantic richness: electrophysiological and behavioral evidence

Words differ considerably in the amount of associated semantic information. Despite the crucial role of meaning in language, it is still unclear whether and how this variability modulates language learning. Here, we provide initial evidence demonstrating that implicit learning in repetition priming is influenced by the amount of semantic features associated with a given word. Electroencephalographic recordings were obtained while participants performed a visual lexical decision task; the complete stimulus set was repeated once. Repetition priming effects on performance accuracy and the N400 component of the event-related brain potential were enhanced for words with many semantic features. These findings suggest a novel and important impact of the richness of semantic representations on learning and plasticity within the lexical-conceptual system; they are discussed in their relevance for assumptions concerning basic mechanisms underlying word learning.     

Landmark use by Clark’s nutcrackers (Nucifraga columbiana): influence of disorientation and cue rotation on distance and direction estimates

Many species have been shown to encode multiple sources of information to orient. To examine what kinds of information animals use to locate a goal we manipulated cue rotation, cue availability, and inertial orientation when the food-storing Clark’s nutcracker (Nucifraga columbiana) was searching for a hidden goal in a circular arena. Three groups of birds were used, each with a different goal–landmark distance. As the distance between the goal and the landmark increased, nutcrackers were less accurate in finding the correct direction to the goal than they were at estimating the distance (Experiment 1). To further examine what cues the birds were using to calculate direction, the featural cues within the environment were rotated by 90° and the birds were either oriented when searching (Experiments 2 and 3) or disoriented (Experiment 3). In Experiment 4, all distinctive visual cues were removed (both internal and external to the environment), a novel point of entry was used and the birds were either oriented or disoriented. We found that disorienting the nutcrackers so that they could not use inertial cues did not influence the birds’ total search error. The birds relied heavily but not completely on cues within the environment, as rotating available cues caused them to systematically shift their search behavior. In addition, the birds also relied to some extent on Earth-based cues. These results show the flexible nature of cue use by the Clark’s nutcracker. Our study shows how multiple sources of spatial information may be important for extracting multiple bearings for navigation.     

Chronic sildenafil (Viagra) administration reduces anxiety in intact and castrated male rats

Epidemiological research indicates that sildenafil (Viagra) abuse is associated with increased risk behaviors. The present study employs the open field, a standard animal model used in the field of anxiety research, to examine whether chronic exposure to sildenafil affects anxiety and risk-taking behaviors in gonadally intact and castrated male Wistar rats. Sildenafil (10 mg/kg) or saline were administered three times a week for three weeks. Animals were tested once a week in the open field during and after drug treatment. Sildenafil treatment increased the number of center entries and time spent in the center in intact and castrated animals during and after treatment, suggesting that repeated drug use decreases anxiety. Sildenafil also restored the deficits in exploration and locomotion produced by castration, indicating that sildenafil effects on open field behaviors are independent of endogenous androgens. We caution against generalizing from this study to human behaviors, but propose that the behavioral effects produced by a chronic high dose of sildenafil warrant further studies into its abuse potential.     

The political economy of poverty in Egypt (1975-2000): A sociological perspective

Studies of poverty in the 1990s have been very successful--more successful than the fight against the phenomenon itself. Had the efforts exerted to combat poverty equalled the concern given to the study of the problem, the poor would have enjoyed better conditions and the level of poverty would have diminished locally and worldwide. The current study identifies the relation between impoverishment, marginalization of particular groups in society and the nature of the political, economic and social policies adopted by the state in Egypt, in one of the important stages of social structure formation in the country--1975-2000. These policies play a direct role in creating the mechanisms of impoverishment and marginalization in Egyptian society, leading naturally to producing and reproducing poverty.     

I recognize your face, but I can't remember your name: A question of expertise?

In four experiments on the identification of familiar faces we reassessed a robust performance pattern—namely, the temporal advantage for retrieving biographical facts as compared to recalling proper names, which has been interpreted as reflecting a serial ordering of the access to semantic and name information. Evidence for recent parallel accounts had been provided by Scanlan and Johnston (1997) who reported an advantage for name retrieval in children. Here we replicated the findings of Scanlan and Johnston but also showed that the naming advantage disappears, and performance is very similar to that of adults when stimuli and tasks are used that are familiar to children. Conversely, we also demonstrated an advantage for name retrieval in adults when highly unfamiliar semantic facts were associated with the faces. Together these findings suggest that there is no fundamental difference in the cognitive architectures of children and adults. The experiments indicate that the relative speed of naming and semantic fact retrieval depends on the expertise with the semantic facts to be retrieved. Implications for models of face identification and naming are discussed.     

Three-configuration matching-to-sample in the pigeon

Pigeons were trained on a zero-delay matching-to-sample procedure during which only three of the four possible stimulus configurations were presented. Subsequently, all birds were exposed to all four configurations as a transfer test. A high degree of negative transfer from the three training configurations was obtained in Experiment 1. The results of Experiment 2 indicated that three-configuration training produced differential position-preference effects. During the transfer test, responding after one sample stimulus was apparently based on position, while responding after the other sample was based on color.     

Do Clark’s nutcrackers demonstrate what-where-when memory on a cache-recovery task?

What-where-when (WWW) memory during cache recovery was investigated in six Clark’s nutcrackers. During caching, both red- and blue-colored pine seeds were cached by the birds in holes filled with sand. Either a short (3 day) retention interval (RI) or a long (9 day) RI was followed by a recovery session during which caches were replaced with either a single seed or wooden bead depending upon the color of the cache and length of the retention interval. Knowledge of what was in the cache (seed or bead), where it was located, and when the cache had been made (3 or 9 days ago) were the three WWW memory components under investigation. Birds recovered items (bead or seed) at above chance levels, demonstrating accurate spatial memory. They also recovered seeds more than beads after the long RI, but not after the short RI, when they recovered seeds and beads equally often. The differential recovery after the long RI demonstrates that nutcrackers may have the capacity for WWW memory during this task, but it is not clear why it was influenced by RI duration.     

Parental Perceptions of Services Provided for Children with Autism in Jordan

Providing formal support for children with autism and their parents is important and mandatory to improve children’s abilities and enhance the capabilities of parents. The present study attempted to investigate the perceptions of parents of children with autism regarding the services provided in Jordan. A questionnaire consisting of five sections was designed and distributed to a sample of 60 parents of children with autism (5–18 years old) among four special education institutions in Jordan. The questionnaire addressed five domains: demographics, type and number of received services, methods and difficulties of obtaining services, parents’ satisfaction, and parents’ perceived needed services. The results revealed that the service delivery system with which parents interacted was composed of multiple places and providers, but had several difficulties. Parents participating in this study expressed an average satisfaction with the received services. Issues pertaining to the cost of services, parents-professional partnerships, and overall quality of services were seen by parents as sources of low satisfaction. On the other hand, parents expressed the need for early intervention, family counseling, and community awareness services. Further suggestions and implications are presented in the study.