Specific impairments in self-regulation in children exposed to alcohol prenatally.

The present study utilizes a conceptual framework derived from theories of cognition to explain the pattern of behavioral and learning problems observed in subjects with fetal alcohol syndrome (FAS) and fetal alcohol effects (FAE). Based on a modern interpretation of Luria's theory of self-regulation, this study used a neuropsychological test battery to compare 10 subjects (mean age = 13 years) having FAS/FAE with 10 control subjects (mean age = 12 years and 9 months). Subjects with FAS/FAE were relatively high functioning and did not significantly differ from controls with respect to receptive vocabulary. However, those with FAS/FAE exhibited greater difficulty than controls on tasks that involved the manipulation of information and goal management in working memory (e.g., Planning, Controlled Oral Word Association, etc). Both groups performed equally well on some tasks that demanded rule learning (Delayed Response) and response inhibition (Go-No-Go). The above impairments were interpreted to be reflective of selective rather than generalized disruptions of neural networks that subserve working memory.

Event-related potentials in cross-modal divided attention in autism.

The behavior and event-related potentials (ERPs) of high functioning subjects with autism (Autism group) were contrasted with the results of normal controls (Control group) during a focused visual attention, a focused auditory attention and a visual/auditory divided attention task. Detecting targets by the Autism group in the cross-modal divided attention condition was more difficult (longer RTs, lower % of correct detections) than attending to one modality. However, both the Autism and Control groups performed all tasks above chance level. The slow negative wave (SNW) was the only negative component which reflected Focused vs Divided task effect in Controls, being largest to stimuli in single channel-focused attention, intermediate when attention was divided between targets of two modalities and smallest to unattended stimuli. Task effects were more evident in the positive peaks for the Autism group. No significant divided attention task effect was noted for P3b, although it was larger for attended than ignored stimuli, of normal morphology and only slightly decreased in size in the Autism group as compared to the Control group. The failure of the Autism group to modulate the slow negative wave in response to Focused/Divided/Ignored conditions in a normal manner, the presence of relatively normal morphology despite the reduced amplitude of the P3b and other positive components, together with the high level of correct target detections are discussed in the context of a selective inhibition deficit and an alternative mechanism of selective attention in autism.

Cephalothoracopagus janiceps malformation. A contribution to the pathogenesis of cerebral malformation.

We report the first histologic findings of the CNS in cephalothoracopagus janiceps monosymmetros. The findings are compared with the other ten reported cases of this type of conjoined twin. The faces and CNSs showed asymmetry of development manifested chiefly in the prosencephalon, specifically the cortical gyri, corpus callosum, and subependymal mantle layer. It is difficult to explain discordance for congenital malformations in monovular or conjoined twins by either genetic or environmental mechanisms. It appears related to the vascular supply of the brain and a state of chronic ischemia rather than to a discrete insult and developmental arrest at a specific time during embryogenesis.

Dyssegmental dwarfism: a new syndrome of lethal dwarfism.

Dyssegmental dwarfism is an autosomal, recessively inherited, lethal, generalized chondrodysplasia characterized by micromelia, cleft palate, and variable limited mobility at the elbow, wrist, hip, knee, and ankle joints and, in some cases, by occipital encephalocele, inguinal hernia, hydronephrosis, hydrocephalus, and patent ductus arteriosus. Roentgenographically, there is a marked variation in the size of all vertebrae with some anterior wedging, coronal clefts, and lack of caudal interpediculate widening. In addition, there are short, broad tubular bones with metaphyseal widening, variable bowing of the tibia, fistula, femur, radius, and minimally the ulna. In the feet, the talus and calcaneus are poorly modeled, and the 1st metatarsal and 1st proximal phalanx are enlarged. The striking similarities among these cases, as well as the others in the literature, argue strongly for their being a common defect in embryogenesis. However, there is also evidence of heterogeneity. Our case reported here has distinct hypoplasia of the scapulae, absence of carpal ossification centers, and lack of flaring of the ilia, whereas the other cases show well-developed scapulas, accelerated carpal bone maturation, and a wide-flared ilia.

Heterogeneity in the campomelic syndromes. Long-and short-bone varieties.

Analysis of 9 cases of bilateral bent limbs (campomelia) and dwarfism, as well as a review of the literature, indicate that campomelic syndrome appears to be a well-defined distinct disorder which the authors call long-limbed campomelic syndrome. Other neonates with congenital bent-limbed dwarfism can be classified as having short-limbed campomelic syndrome, and among these at least two distinct forms have been delineated--the craniosynostotic and the normocephalic form. Congenital bent bones also occur in a variety of generalized disorders of ossification that must be distinguished from these well-defined types of campomelic dwarfism.

Heterogeneity in the campomelic syndromes: long and short bone varieties.

There appears to be definite heterogeneity within the campomelic syndromes. We are broadly classifying these into the classic or long bone campomelic syndromes and 2 distinct short bone varieties designated as the normocephalic short-boned and craniosynostotic short-boned types, respectively (Table 1).