Cognitive development during each of the major stages identified by Piaget is characterized by abilities to solve progressively more complex tasks (e.g., changes in the object concept during the sensori-motor stage, and in conservation of amount, weight, and volume during the concrete operational stage). Several theorists have suggested that these…

The two-level theory of mental abilities posits two broad classes of ability: level I (learning and memory) and level II (the "g" factor of intelligence tests, reasoning, abstraction, and problem solving). Levels I and II are hypothesized to interact with SES and/or race such that: (l) SES differences are greater for level II than for I,…

This paper examines the discriminative validity of the Learning Efficiency Test II (LET-II; Webster, 1998) in distinguishing among children diagnosed as having ADHD (Attention Deficit Hyperactivity Disorder) only, ADHD and an accompanying learning disability, ADHD-predominantly inactive type, and a control group. Children (N=132) between the ages…

Reveals a two-factor structure (general retentiveness and memory) in the Wechsler Memory Scale for total male and female samples and for both males and females aged 13 to 39 years and 40 to 59 years but not for males or females aged 60 to 88 years. (Author/RL)