Berridge has proposed that in some addictions the brain becomes sensitized to the wanting cycle of a particular reward. So addicts become obsessively driven to seek the reward, even as the reward itself becomes progressively less rewarding once obtained. “The dopamine system does not have satiety built into it,” Berridge explains. “And under certain conditions it can lead us to irrational wants, excessive wants wedd be better off without.” So we find ourselves letting one Google search lead to another, while often feeling the information is not vital and knowing we should stop. “As long as you sit there, the consumption renews the appetite,” he explains.
Actually all our electronic communication devices—e-mail, Facebook feeds, texts, Twitter—are feeding the same drive as our searches. Since we're restless, easily bored creatures, our gadgets give us in abundance qualities the seeking/wanting system finds particularly exciting. Novelty is one. Panksepp says the dopamine system is activated by finding something unexpected or by the anticipation of something new. If the rewards come unpredictably—as e-mail, texts, updates do—we get even more carried away. No wonder we call it a ‘CrackBerry.’
The system is also activated by particular types of cues that a reward is coming. In order to have the maximum effect, the cues should be small, discrete, specific—like the bell Pavlov rang for his dogs. Panksepp says a way to drive animals into a frenzy is to give them only tiny bits of food: This simultaneously stimulating and unsatisfying tease sends the seeking system into hyperactivity. Berridge says the “ding” announcing a new e-mail or the vibration that signals the arrival of a text message serves as a reward cue for us.
And how about this?
The juice that fuels the seeking system is the neurotransmitter dopamine. The dopamine circuits “promote states of eagerness and directed purpose,” Panksepp writes. It’s a state humans love to be in. So good does it feel that we seek out activities, or substances, that keep this system aroused—cocaine and amphetamines, drugs of stimulation, are particularly effective at stirring it.
Ever find yourself sitting down at the computer just for a second to find out what other movie you saw that actress in, only to look up and realize the search has led to an hour of Googling? Thank dopamine. Our internal sense of time is believed to be controlled by the dopamine system. People with hyperactivity disorder have a shortage of dopamine in their brains, which a recent study suggests may be at the root of the problem.