Familial epilepsy and developmental dysphasia: description of an Italian pedigree with autosomal dominant inheritance and screening of candidate loci.

PURPOSE: To describe a familial epileptic condition combining a peculiar electro-clinical pattern with developmental language dysfunction in a large Italian kindred. METHODS: We studied the clinical and neurophysiological features of a 4-generation family with 10 affected members (3 deceased). We also analysed in 7 affected and 7 healthy members microsatellite markers for 51 candidate loci for epilepsy, including 42 loci containing ion channel genes expressed in the brain, as well as the SPCH1 and SRPX2 loci. RESULTS: Five of the seven living affected members (aged 20-58 years) had the full phenotype (seizures, EEG epileptiform abnormalities and dysphasia). The language dysfunction was the first symptom, becoming evident since the period of language development and mainly consisting of phonemic and syntactic paraphasias, difficulty of expression and reduced verbal fluency. The seizures had their onset between 2 and 23 years and were reported as epileptic falls (4) associated or not with myoclonic features, absences (3), tonic-clonic (1) and complex partial seizures (1). The seizures were easily controlled by antiepileptic treatment in all patients except one. In the five patients with a good response of seizures to treatment, the EEG tracings showed the coexistence of focal and generalized epileptiform abnormalities; in the refractory patient the interictal EEG demonstrated bilateral asynchronous fronto-temporal paroxysms with left predominance and ictal SEEG recording suggested a multifocal origin of the discharges. MRI of the brain was normal in all patients. Linkage analysis provided negative LOD scores for all the investigated loci. CONCLUSION: We have described a novel familial pattern of epilepsy and developmental dysphasia which is not genetically linked to epilepsy or speech disorder loci, as documented by a candidate-gene linkage approach.

A comparison of the reach-to-grasp movement between children and adults: a kinematic study.

In this study, the reach-to-grasp movement of 5-year-old children was compared to that of adults. Participants were required to reach out and grasp objects, with and without on-line visual feedback. Object size and distance were covaried in a within-subjects design and it was found that for both groups, grip formation and reach kinematics were affected by the manipulation of either variable. Although there are a large number of similarities, a few differences between the two groups emerge. For the reaching component, the children revealed a longer movement duration and deceleration time and a lower maximum height of wrist trajectory than in adults. For the grasp component, the children, in both the vision and no-vision condition, show a maximal finger aperture larger than the adults. Further, the children of this study were able to scale their grip aperture according to object size when visual feedback during the movement was lacking. These findings suggest that children adopt different strategies than adults when planning a reach-to-grasp movement on the basis of object size, distance, and the predictability of visual feedback. The results are discussed in terms of the neural mechanisms underlying hand action and how these mechanisms may not be fully developed by the age of 5.

Reaching in children with and without developmental coordination disorder under normal and perturbed vision.

The aim of this study is to describe the reaching action of children with developmental coordination disorder (DCD) and to investigate whether their use of visual feedback during the time course of this action differs from that of normally developing children. Fifty-two children subdivided into 2 age bands (7-8 and 9-10 years) within 2 groups (with and without DCD) participated in this experiment. They were asked to reach for a target positioned either ipsilaterally or contralaterally to the reaching hand in 2 visual conditions: a condition where vision was unrestrained (normal vision) and a condition where they wore glasses with prismatic lenses (perturbed vision). An analysis of the experimental data indicates that the trajectories followed by the DCD group were longer and more curved than those of the control group. Further, the deceleration times were longer for the DCD group than for the normally developing children. The introduction of the prismatic lenses supports the idea that the use of visual feedback by children with DCD may be different from that in children without DCD.

Evidence of early development of action planning in the human foetus: a kinematic study.

The aim of the present study was to investigate whether foetal hand movements are planned and how they are executed. We performed a kinematic analysis of hand movements directed towards the mouth and the eyes in the foetuses of eight women with normally evolving pregnancies. At 14, 18 and 22 weeks of gestation, eight foetuses underwent a 20-min four-dimensional-ultrasound session. The video recordings for these movements were then imported into in-house software developed to perform kinematic analysis. We found that spatial and temporal characteristics of foetal movements are by no means uncoordinated or unpatterned. By 22 weeks of gestation the movements seem to show the recognizable form of intentional actions, with kinematic patterns that depend on the goal of the action, suggesting a surprisingly advanced level of motor planning.

Performance of gesture in children with and without DCD: effects of sensory input modalities.

This study aimed to investigate the extent to which gesture performance depends on input modality and whether gestural development patterns differ in children with and without developmental coordination disorder (DCD). Therefore, development of limb gesture was studied in 140 children--105 control children (94 males, 11 females) and in 35 children with DCD (29 males, six females) divided into three age bands: 5 to 6 years, 7 to 8 years, and 9 to 10 years. Transitive gestural skills were investigated through four input modalities: Imitation, Visual plus Tactile, Visual, and Verbal. Results indicate that limb gestural skills in normally developing children follow a progressive maturation pattern: Imitation, Visual plus Tactile, and visual routes appear to mature before the verbal route and appear to be available earlier to enable the child to perform a correct gesture. The performance of children with DCD throughout the four modalities suggested a general maturational delay. When gestures were required through the Verbal modality, there was a specific deficit in using sensory-motor information and in integrating it into a motor representation. In the Verbal modality, children with DCD performed consistently worse than their control peers and the difference in performance tended to increase rather than improve with age.