You will now read a short passage and listen to a lecture on the same topic. You will then

be asked a question about them. After you hear the question, give yourself 30 seconds to prepare your response. Then record yourself speaking for 60 seconds. Critical Period It is generally believed that for many organisms, there is a specific time period, a so-called "window of opportunity," during which the organism must receive crucial input from its environment in order for normal development to occur. This period is called the critical period. If the needed environmental input is not received during this period, the normal development of certain physical attributes or behaviors may never occur. In other words, if the organism is not provided with the needed stimulus or influence during the critical period, it may permanently lose the capacity to ever obtain a particular physical attribute or behavior. Listen to Track 81.

Using the examples of kittens and geese, explain the idea of a critical period.