The pursuit of happiness is the engine that moves humankind, that motivates us to study, to work, to marry and have children, to make friends, to pursue all sorts of worldly pleasures, to dream of the future, and sometimes to fight for social and financial status. Of all the goals we may pursue in life, happiness is the only one to have worth in itself; all the others—health, power, money, beauty, success—make sense only as means of achieving it. To many people, life would be unbearable without the belief that they can be happy.

Are our brains “hardwired” for happiness? That is, does happiness have a biological basis, rooted in the evolution of the nervous system? If so, understanding how our brain machinery works to make us happy could suggest ways to transform our behavior and our relationships with others, as well as to set up a better society.

Of course, to define happiness objectively is difficult.  Joseph Ledoux, Ph.D., the well-known researcher and author on the physiology of emotions, expressed the scientist’s frustrations with this elusive entity well when he wrote: “There are many answers for what are emotions/happiness. Many of them are surprisingly unclear and ill-defined.”  Neuroscientist Richard J. Davidson, Ph.D., observed that the word happiness “is a kind of a placeholder for a constellation of positive emotional states. Of all the emotions, happiness is the one scientists least understand.”

Studying the many enemies of happiness, such as stress, depression, anxiety, and phobias, is essential, of course, but recently researchers have turned their attention to the brains of happy people as well. Even though scientists still do not agree on the precise definition of happiness, they are beginning to discover a vast array of biological counterparts to what we associate with the idea of happiness. Functional imaging methods and the study of key neurotransmitters in the mechanisms of emotion in the brain and body have led not only to a deeper understanding of the biological components of happiness but also to practical applications for achieving it, such as antidepressant drugs. 

Searching for Happiness in the Brain

Neuroscience, biology, and psychology all have important roles in deciphering and elucidating the mechanisms and purpose of positive emotions. Great scientists, from Charles Darwin to William James to Sigmund Freud, have studied in detail our most basic negative emotional processes, such as fear, stress, anxiety, anger, and aggression, and how they relate to the brain, nervous system, hormones, and internal organs. Their findings provided most of the knowledge we have today about the neural correlates of emotion in general, particularly the role of subcortical structures such as the limbic system, hypothalamus, thalamus, basal ganglia, and midbrain.

Positive emotions, however, used to be considered too subjective and difficult to study, so for a long time neuroscientists neglected them. Unhappiness was considered to arrive on its own, since fear, anger, and defense are responses to danger from the external world and are vital for our survival (“fight or flight”). But our feelings of pleasure and happiness were thought to be largely cultural and were regarded only as guiding our behavior toward desirable situations. 

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