Final answer:
Arthur Jensen posited that genetics played a significant role in determining intelligence, which was later disputed by research emphasizing environmental influences and the negative impact of socioeconomic status on cognitive development.
Step-by-step explanation:
Arthur Jensen, an educational psychologist, believed that intelligence was largely determined by genetics. His controversial work supported the notion that Level II types of intelligence, which are responsible for conceptual and analytical abilities, varied among ethnic groups. Jensen's views were challenged by substantial research refuting a biological-racial basis for intelligence and highlighting the significant role of environmental factors.
Furthermore, twin studies, like the Minnesota Study of Twins Reared Apart, suggest that there is a genetic component to intelligence, showing higher correlations of IQ scores between identical twins, regardless of whether they were raised together or apart. However, other psychologists emphasize that a child's developmental environment greatly shapes intelligence, where intellectual stimuli play a crucial role. The impact of socioeconomic status on intelligence is also significant, with factors such as poverty affecting brain function and development, potentially lowering IQ scores.