INAUGURAL ARTICLE by a Recently Elected Academy Member:Coming to terms with fear

The brain mechanisms of fear have been studied extensively using Pavlovian fear conditioning, a procedure that allows exploration of how the brain learns about and later detects and responds to threats. However, mechanisms that detect and respond to threats are not the same as those that give rise to conscious fear. This is an important distinction because symptoms based on conscious and nonconscious processes may be vulnerable to different predisposing factors and may also be treatable with different approaches in people who suffer from uncontrolled fear or anxiety. A conception of so-called fear conditioning in terms of circuits that operate nonconsciously, but that indirectly contribute to conscious fear, is proposed as way forward.

Hunger, like, anger, fear, and so forth, is a phenomenon that can be known only by introspection. When applied to another…species, it is merely a guess about the possible nature of the animal’s subjective state.Nico Tinbergen (1)Neuroscientists use “fear” to explain the empirical relation between two events: for example, rats freeze when they see a light previously associated with electric shock. Psychiatrists, psychologists, and most citizens, on the other hand, use…“fear” to name a conscious experience of those who dislike driving over high bridges or encountering large spiders. These two uses suggest…several fear states, each with its own genetics, incentives, physiological patterns, and behavioral profiles.Jerome Kagan (2)

My research focuses on how the brain detects and responds to threats, and I have long argued that these mechanisms are distinct from those that make possible the conscious feeling of fear that can occur when one is in danger (3–6). However, I, and others, have called the brain system that detects and responds to threats the fear system. This was a mistake that has led to much confusion. Most people who are not in the field naturally assume that the job of a fear system is to make conscious feelings of fear, because the common meaning of fear is the feeling of being afraid. Although research on the brain mechanisms that detect and respond to threats in animals has important implications for understanding how the human brain feels fear, it is not because the threat detection and defense responses mechanisms are fear mechanisms. It is instead because these nonconscious mechanisms initiate responses in the brain and body that indirectly contribute to conscious fear.In this article, I focus on Pavlovian fear conditioning, a procedure that has been used extensively to study the so-called fear system. I will propose and defend a different way of talking about this research, one that focuses on the actual subject matter and data (threat detection and defense responses) and that is less likely to compel the interpretation that conscious states of fear underlie defense responses elicited by conditioned threats. It will not be easy to give up the term fear conditioning, but I think we should.