Passage Five 

Beyond the basic animal instincts to seek food and avoid pain, Freud identified two sources of psychic energy, which he called "drives": aggression and libido. The key to his theory is that these were unconscious drives, shaping our behavior without the mediation of our waking minds; they surface, heavily disguised, only in our dreams. The work of the past half-century in psychology and neuroscience has been to downplay the role of unconscious universal drives, focusing instead on rational processes in conscious life. But researchers have found evidence that Freud's drives really do exist, and they have their roots in the limbic system, a primitive part of the brain that operates - 10 - mostly below the horizon of consciousness. Now more commonly referred to as emotions, the modern suite of drives comprises five: rage, panic, separation distress, lust and a variation on libido sometimes called seeking. 

The seeking drive is proving a particularly fruitful subject for researchers. Although like the others it originates in the limbic system, it also involves parts of the forebrain; the seat of higher mental functions. In the 1980s, Jaak Panksepp, a neurobiologist at Bowling Green State University in Ohio, became interested in a place near the cortex known as the ventral tegmental area, which in humans lies just above the hairline.When Panksepp stimulated the corresponding region in a mouse, the animal would sniff the air and walk around, as though it were looking for something. Was it hungry? No. The mouse would walk right by a plate of food, or for that matter any other object Paksepp could think of. This brain tissue seemed to cause a general desire for something new."What I was seeing," he says,"was the urge to do stuff." Panksepp called this seeking. 

To neuropsychologist Mark Solms of University College in London, that sounds very much like libido."Freud needed some sort of general, appetitive desire to seek pleasure in the world of objects," says Solms. Panksepp discovered as a neuroscientist what Freud discovered psychologically." Solms studied the same region of the brain for his work on dreams. Since the 1970s, neurologists have known that dreaming takes place during a particular form of sleep known as REM—rapid eye movement—which is associated with a primitive part of the brain known as the pons. Accordingly,they regarded dreaming as a low-level phenomenon of no great psychological interest. When Solms looked into it, though, it turned out that the key structure involved in dreaming was actually the ventral tegmental, the same structure that Panksepp had identified as the seat of the "seeking" emotion. Dreams, it seemed, originate with the libido— which is just what Freud had believed.

Freud's psychological map may have been flawed in many ways, but it also happens to be the most coherent and, from the standpoint of individual experience, meaningful theory of the mind. "Freud should be placed in the same category as Darwin, who lived before the discovery of genes," says Panksepp. "Freud gave us a vision of a mental apparatus. We need to talk about it, develop it, test it." Perhaps it's not a matter of proving Freud wrong or right, but of finishing the job.