The human brain responds to recognizable signals for sex and for rewarding drugs of abuse by activation of limbic reward circuitry. Two days after scanning, the affective valence for visible versions of each cue type was determined using an affective bias priming task.
These findings represent the first evidence that brain reward circuitry responds to drug and sexual cues presented outside awareness. The limbic brain response to reward cues outside awareness may represent a potential vulnerability in disorders e.
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At the end of the nineteenth century, Freud [1] proposed that much of human motivation β both fears and desires β occurs outside awareness. This notion had a profound impact on the culture of the past century, without being easily testable. Functional brain imaging can now be used to test whether the brain responds to cues of motivational significance, even when presented outside awareness. Neuroimaging studies have shown that the brain e.
Some reward signals e. Whether the brain responds to reward signals of either type β when presented outside awareness β is not yet known; we tested both types in the current study. Extended β seconds or minutes-long β exposures to relevant cocaine [9] and sexual [10] , [11] stimuli can trigger conscious desire and activation of interconnected limbic e.
