Final answer:
Research on changes in cognitive functioning in later life is difficult to interpret due to the need to separate the effects of aging from genetic factors, socioeconomic status, and environmental influences.
Step-by-step explanation:
Research on changes in cognitive functioning in later life is difficult to interpret because it is challenging to separate the effects of aging from genetic factors, socioeconomic status, and environmental influences. Genetic factors can influence cognitive functioning as certain diseases like Alzheimer's have a genetic basis. Socioeconomic status can also impact cognitive functioning as individuals with higher socioeconomic status may have better access to resources that support cognitive health. Additionally, environmental influences, such as exposure to toxins or engaging in mentally stimulating activities, can affect cognitive functioning in later life.