Cannon and washburn's classic experiment on hunger revealed that when subjects reported: thirst, their stomach muscles were relaxing. satiation, their stomachs were contracting. hunger, their stomachs were contracting. thirst, their stomachs were empty.

In this classic experiment, Cannon and Washburn report that when we are hungry, our stomach contracts. To test this theory, Washburn swallowed a ball with a tube, when the ball in his stomach was inflated, he did not feel hungry, on the contrary, when the ball was deflated and his stomach was empty, it contracted generating a feeling of hunger.

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