In: Psychology
Maze navigation ability is an indicator of cognitive performance in rats. Consider an experiment where some mice from a maze-bright strain are reared in a restricted environment (Group A) whereas others are reared in their normal environment (Group B) and answer the following questions.
1. If maze-navigation ability is only influenced by genetics, how would you expect the maze navigation performance of rats from Group A to compare with those from Group B?
2. If maze-navigation ability is affected by a genotype-environment interaction, how would you expect the maze navigation performance of rats from Group A to compare with those from Group B?
The question at hand harks back to Tryon's 1940 rat experiment where he challenged the then-existing notion that environment is the determining factor of intelligence and behaviour as opposed to genes. The underlying principle of this question is the classic nature-versus-nurture debate that essentially asks the following question:
Is behaviour/intelligence inherited from our genes or learned from our environment?
"Consider an experiment where some mice from a maze-bright strain are reared in a restricted environment (Group A) whereas others are reared in their normal environment (Group B)."
Before moving to the answer to questions that follow, here are a few terms to understand:
1. If maze-navigation ability is only influenced by genetics, the maze navigation performance of rats from Group A will be equal as compared with those from Group B, because the environment should logically play no role in how the mice performed if it is only influenced by genetics. Since both mice from Group A and Group B are from the same maze--bright strain (genetic factor), there should be no difference in their performance despite their differing environments.
2. If maze-navigation ability is affected by a genotype-environment interaction, the maze navigation performance of rats from Group A will be different compared with those from Group B. This is because, while genetically, mice from Group A and Group B may be identical, their environments are different. Mice from Group A can be expected to perform more poorly than mice from Group B; the former (Group A) were in a restricted environment that was unstimulating and is likely to negatively impact cognitive performance even though genetically gifted (maze-bright) as opposed to mice from Group B who got both the environmental advantage (normal environment) and genetic advantage (maze-bright).