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9.1.1: Learning Objectives and Introduction
Opening the book…
Learning Objectives
Identify the key properties of drive states
Describe biological goals accomplished by drive states
Give examples of drive states
Outline the neurobiological basis of drive states such as hunger and arousal
Discuss the main moderators and determinants of drive states such as hunger and arousal
Introduction
What is the longest you’ve ever gone without eating? A couple of hours? An entire day? How did it feel? Humans rely critically on food for nutrition and energy, and the absence of food can create drastic changes, not only in physical appearance, but in thoughts and behaviors. If you’ve ever fasted for a day, you probably noticed how hunger can take over your mind, directing your attention to foods you could be eating (a cheesy slice of pizza, or perhaps some sweet, cold ice cream), and motivating you to obtain and consume these foods. And once you have eaten and your hunger has been satisfied, your thoughts and behaviors return to normal.
Hunger is a drive state, an affective experience (something you feel, like the sensation of being tired or hungry) that motivates organisms to fulfill goals that are generally beneficial to their survival and reproduction. Like other drive states, such as thirst or sexual arousal, hunger has a profound impact on the functioning of the mind. It affects psychological processes, such as perception, attention, emotion, and motivation, and influences the behaviors that these processes generate.