<span>Dennis' behavior can be best characterized as "social loafing".
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Social loafing depicts the propensity of people to advance less exertion when they are a piece of a gathering. Since all individuals from the gathering are pooling their push to accomplish a shared objective, every individual from the gathering contributes short of what they would on the off chance that they were exclusively mindful.
Answer: Amygdala
Explanation: Amygdala is a major composition of the brains of complex animals including Man, Squirrel etc. It is the composition of the Brain that helps to react during fear condition. If the Amygdala is damaged it will be difficult or impossible for the Animal to react to fear,like the case of the Squirrel to signals from an impending shock after the damage of its Amygdala.
Answer: Gestalt psychology.
Originator of gestalt psychology is Fritz Perls.