Static and dynamic balance skills of trainable children with Down's syndrome.

This study compared static and dynamic balance performance of 25 subjects with Down's Syndrome and 25 without Down's Syndrome; controls were placed on CA and IQ. No significant difference between the two samples' static balance performance was noted; subjects with the Down's Syndrome had significantly superior dynamic balance performance.     

Insertion of connectives by 9- to 11-year-old children in an argumentative text

The objective of the present study was to show that the use of adversative and conclusive connectives to mark off the prototypical schema of argumentative text begins to set in at approximately the age of 10 or 11. Based on Adam's (1992) proposals, we constituted an argumentative text with two blocks of arguments separated by an adversative instruction (the connective but or an equivalent) and followed by a conclusion introduced by a conclusive instruction (the connective thus or an equivalent). Four revising tasks (insertion or substitution with or without five connectives) have been used to asses children's knowledge of the argumentative schema and the use of connectives that punctuate them. The study of good and erroneous locations (concerning the placement of but and thus) showed that there was some regularity in the choices made by the children. The main result of this study shows that argumentative connectives are used differently by children aged 9 and children aged 10 or 11. The argumentative schema is used more consciously by 11-year-olds to guide revising tasks than by 10-year-olds.     

Language Development in Children with Simple-Partial Left-Hemisphere Epilepsy

The nature of cerebral involvement in the acquisition of language was addressed in this longitudinal study of children with an early diagnosis of epilepsy with simple-partial seizures (SPE) and with epileptogenic foci localized in the left frontal (LF) lobe. Yearly evaluations of six SPE-LF children on tests of linguistic comprehension (pointing, understanding of narrative, and understanding of prepositions) and production (repetition, lexical diversity, and grammatical production) were carried out between the ages of 3 and 8 years and compared to those of large samples of control children on the same tasks and at each age level. Linguistic production of all children were transcribed, coded, and analyzed using the Child Language Data Exchange System (MacWhinney & Snow, 1991). Individual evolution trajectories revealed that SPE-LF children showed a clear dissociation in linguistic performance between comprehension and production. Linguistic comprehension gradually improved to reach normal performance levels by age 7 while linguistic production, even at later stages, remained quite poor. This dissociation in the development of linguistic performance in SPE-LF children suggests a complex interplay between brain maturation dynamics and dysfunction modulating the succession of stages in language development. The observed persistent deficits in specific aspects of linguistic performance argue for an early involvement of the anterior areas of the left cerebral hemisphere in the production of language.     

Position of the Egocentric Reference and Directional Arm Movements in Right-Brain-Damaged Patients

We asked 12 right-brain-damaged patients (6 with left neglect signs and 6 without left neglect signs) to perform a straight ahead pointing task and a visual detection task with lateralized motor response, in order to investigate the relationship between the position of the egocentric reference and response time and accuracy in producing lateralized arm movements. Results showed that there was no correlation between the position of the egocentric reference and neglect signs, nor between the position of the egocentric reference and the latencies to direct a motor response toward either side of space. These findings were interpreted within the context of egocentric hypotheses of neglect. In particular, it was suggested that attentional or intentional neglect signs cannot be considered as a direct consequence of an ipsilesional deviation of the egocentric reference.     

Evidence for the Involvement of the Rat Prefrontal Cortex in Sustained Attention

Previous studies suggest that, in both humans and rats, the prefrontal cortex (PFC) is involved in both selective and divided attention. We have also shown that the PFC is involved in response selection and that its involvement is modulated by the cognitive effort required by the task. However, the role of the PFC is much less clear when no response selection is required. The purpose of the present experiments was to assess the role of the PFC in attentional functions with a low response-selection demand. We used two tasks in which information processing was effortful but where the demand on a response selection process is low. Moreover, we assessed two different types of visual attentional functions: selective attention (Experiment 1) and sustained attention (Experiment 2). The results showed a differential involvement of the PFC in the two tasks. Selective attention was not impaired by prefrontal lesions when the number of possible positions for the stimulus on which the subjects must focus was restricted to two (Experiment 1). In contrast, prefrontal rats were unable to sustain their attention long enough to detect, and react to, subtle variations in brightness (Experiment 2). This result suggests a dissociation between different types of attentional functions depending upon the integrity of the PFC. More specifically, results in Experiment 2 suggest an involvement of the PFC in sustained attention. Finally, the overall results show that even in tasks involving low demands on response selection the PFC is involved in attentional functions.     

A case of behavioral heterosis in mice: quantitative and qualitative aspects of performance in a water-escape task.

Fourteen hundred and four mice from two inbred strains (Balb/c and C57BL/6), F1, F2, and backcrosses were subjected to four trials in a water-escape task and to a swimming test. Detailed analysis of mice behavior in these situations showed that the "F1 hybrid vigor" affected behavioral characters not directly related to physical vigor but of potential adaptive value. Their superiority was mainly due to more frequent adoption of an efficient behavioral tactic (direct or edge escape paths toward the exit) and more rapid progress with experience in this respect than other generations exhibited. These results clearly show that heterosis is not limited to physical vigor but may extend to behavioral and even psychological characters.     

THE POST-METROPOLIS IS GOD: Notes for a Phenomenology of the Urban Spirit

Topoi - More akin to the Roman Empire’s concept of civitas mobilis augescens, the distinction between the twentieth-century metropolis and the Roman model of a city must be sought in the...