After reading this chapter, you will be able to:

• Describe how scientists have defined intelligence.
• Critique the scientific methods for measuring intelligence.
• Identify how the structure of the nervous system relates to intelligence.
• Appraise the relative contributions of heredity and environment to intelligence.
• Assess the impact of the typical aging process on cognitive functioning.
• Compare the impacts of intellectual disability, autism, and attention-deficit/hyperactivity disorder on intelligence.