What Did the Researcher Nathaniel Kleitman Do to Determine Whether

question 58

Multiple Choice

What did the researcher Nathaniel Kleitman do to determine whether sleep-wake rhythms persisted without external cues of light?

• A) Taped his eyes shut.
• B) Lesioned the retinohypothalamic tract in his cat.
• C) Placed rats in complete darkness.
• D) Lived in an underground chamber for a month.

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