LONDON — The effects of love on the brain are similar to those of cocaine, according to a team that has studied scans of love-struck people.

Romantic love could be an emotion as fundamental as hunger or thirst, according to the brain scans of young men and women who had fallen madly in love, or were lovelorn, by Arthur Aron, a social psychologist at the State University of New York at Stony Brook.

The finding is based on research he carried out with Lucy Brown, a neuroscientist at Albert Einstein College of Medicine in New York and Helen Fisher, an anthropologist at Rutgers University.

While participants felt many different emotions when thinking of the person they loved, they all had one thing in common — they all showed activation in the ventral tegmental area, the right posterodorsal body, and the medial caudate nucleus of the brain, according to the journal Monitor on Psychology.

These dopamine-rich regions “signal satiation of deep needs,” said Ms. Fisher. “All basic drives are associated with the dopamine system, and so is romantic love.”

Known as the motivation-and-reward system of the brain, the regions appear to be active whenever people get something they deeply desire — food, water, cocaine, or perhaps just a girlfriend’s phone call in the case of teenage boys.

Ms. Fisher said: “Addictions are very powerful, and cocaine addiction is strongly associated with dopamine systems.”

She also speculated that the increase in energy people newly in love experience may be due to a flush of dopamine.

“Dopamine system activation is also related to focused attention, underpinning the feeling that just one person is at the focus of your world — your absolute and total Valentine,” added Mr. Aron.

Some of the brain systems activated in people who are in love are similar to those active in people who have been recently rejected, according to an as-yet-unpublished study by the same team. This time they studied 15 lovelorn young people as they looked at pictures of their former partners.

As with the students in love, the bereft showed increased activation in the motivation and reward systems. Unlike them, the lovelorn showed activation in an area of the brain associated with taking risks.

The Gresham Professor for Public Understanding of Psychiatry, Raj Persaud, who organized a Telegraph online Valentine’s experiment, said, “What this important research is adding to is our understanding that love is one of the strongest of the basic drives — people when in love do extraordinary things.”