Between 40% and 80% of the variation in human intelligence (IQ) is attributable to genetic factors. Except for many rare mutations resulting in severe cognitive dysfunction, attempts to identify these factors have not been successful. We report a genomewide linkage scan involving 634 sibling pairs designed to identify chromosomal regions that explain variation in IQ. Model-free multipoint linka...

Language Development and Intelligence in Preschoolers A.Razavi, Ph.D. S. Haghighat, Ph.D. T. Vaa’ezi Although almost all theoretical perspectives on language development maintain that a relationship of sorts exists between language and general concept of intelligence, the present research looked at this relationship among a random sample of Neyshaaboori preschoolers (4...

Results 44 subjects from 42 families (22 men), mean age of 42 years were included. KBIT-2 Composite IQ score was 98.4 ± 12.4, (95% CI (confidence interval) 94.5-102.3) which is within the average range of 90-109. 27 % of patients scored below average (less than 90) and 15% scored above average (greater than 109), not a significant imbalance (sign test p=0.33). Nonverbal IQ scores show no differ...

We administered a semantic verbal fluency (SVF) task to two groups of children (age range from 5 to 8): 47 diagnosed with Autism Spectrum Disorder (ASD Group) and 53 with typical development (Comparison Group), matched on gender, chronological age, and non-verbal IQ. Four specific indexes were calculated from the SVF task, reflecting the different underlying cognitive strategies used: clusterin...

Individual differences in inspection time explain about 20% of IQ test variance. To determine whether the association between inspection time and IQ is mediated by common genes or by a common environmental factor, inspection time and IQ were assessed in an extended twin design. Data from 688 participants from 271 families were collected as part of a large ongoing project on the genetics of adul...

OBJECTIVE Attention-deficit/hyperactivity disorder (ADHD) is often associated with reduced IQ and high levels of externalizing behavior (EB). This study tested if DRD4 7-repeat allele and DAT1 10-repeat allele homozygosity interact in modulating correlations between IQ and EB in affected boys. METHODS Boys (n=130) between 6 and 12 years of age diagnosed with ADHD were included in the study. I...

G A A b st ra ct s association of anxiety and gastrointestinal disorders in these children. Increased severity of anxiety symptoms is associated with the diagnosis of Asperger's and with higher IQ in children with ASD. Whether or not there is any relationship between anxiety and GI symptoms in children with ASD is not known Objectives: To characterize chronic GI symptoms in children with ASDs a...

Now, in its third revision, the Wechsler Adult Intelligence Scale-III has a new factor structure. The theoretical structure of the new instrument is hierarchical in nature and contains four firstorder factors with a second-order g factor at the apex. In addition to the theoretical hierarchical factor structure of the new instrument, there is an implied factor structure that is used for scoring....

The Wechsler Adult Intelligence Scale was administered serially to 40 severely head-injured adults, and the results compared with a matched group of 40 non-injured men. The scores on the verbal subtests showed less initial impairment and were faster to recover to the level of the comparison group than were the non-verbal subtest scores. Verbal IQ of the head-injury group approached that of the ...