Lately, some neuroscientists have been struggling with an identity crisis: what do we believe, and what do we want to achieve? Is it enough to study the brain’s machinery, or are we missing its larger design?
Scholars have pondered the mind since Aristotle, and scientists have studied the nervous system since the mid-1800s, but neuroscience as we recognize it today did not coalesce as a distinct study until the early 1960s. In the first ever Annual Review of Neuroscience, the editors recalled that in the years immediately after World War II, scientists felt a “growing appreciation that few things are more important than understanding how the nervous system controls behavior.” This “growing appreciation” brought together researchers scattered across many well-established fields – anatomy, physiology, pharmacology, psychology, medicine, behavior – and united them in the newly coined discipline of neuroscience.
It was clear to those researchers that studying the nervous system needed knowledge and techniques from many other disciplines. The Neuroscience Research Program at MIT, established in 1962, brought together scientists from multiple universities in an attempt to bridge neuroscience with biology, immunology, genetics, molecular biology, chemistry, and physics. The first ever Department of Neurobiology was established at Harvard in 1966 under the direction of six professors: a physician, two neurophysiologists, two neuroanatomists, and a biochemist. The first meeting of the Society for Neuroscience was held the next year, where scientists from diverse fields met to discuss and debate nervous systems and behavior, using any method they thought relevant or optimal.
These pioneers of neuroscience sought to understand the relationship between the nervous system and behavior. But what exactly is behavior? Does the nervous system actually control behavior? And when can we say that we are really “understanding” anything?
It may sound pedantic or philosophical to worry about definitions of “behavior,” “control,” and “understanding.” But for a field as young and diverse as neuroscience, dismissing these foundational discussions can cause a great deal of confusion, which in turn can bog down progress for years, if not decades. Unfortunately for today’s neuroscientists, we rarely talk about the assumptions that underlie our research.
“Understanding,” for instance, means different things to different people. For an engineer, to understand something is to be able to build it; for a physicist, to understand something is to be able to create a mathematical model that can predict it. By these definitions, we don’t currently “understand” the brain – and it’s unclear what kind of detective work might solve that mystery.
Many neuroscientists believe that the detective work consists of two main parts: describing in great detail the molecular bits and pieces of the brain, and causing a reliable change in behavior by changing something about those bits and pieces. From this perspective, behavior is an easily observable phenomena – one that can be used as a measurement.
But since the beginning of neuroscience, a vocal and persistent minority has argued that detective work of this kind, no matter how detailed, cannot bring us closer to “understanding” the relationship between the nervous system and behavior. The dominant, granular view of neuroscience contains several problematic assumptions about behavior, the dissenters say, in an argument most recently made earlier this year by John Krakauer, Asif Ghazanfar, Alex Gomez-Marin, Malcolm MacIver, and David Poeppel in a paper called “Neuroscience Needs Behavior: Correcting a Reductionist Bias.”