Sunday, March 8, 2009
Science of time: What makes our internal clock tick
Says UCLA neuroscientist Dean Buonomano: "In order to understand the nature of the human mind, we must unravel the mystery of how the brain tells time, in both normal and pathological states." Against that backdrop, the temporally challenged have become more scientifically relevant than ever. Neuroscientists have come to recognize that patients with devastating brain disorders such as Parkinson's and Huntington's diseases greatly underestimate the passage of time. Poor timing is a hallmark in several psychiatric conditions, including schizophrenia, autism and attention deficit disorder.
Many of about 5,500 soldiers returning from Iraq and Afghanistan with traumatic brain injury will find that faulty timing is one of the invisible wounds that follow them into civilian life. And researchers have confirmed that as we reach senior status, our internal clock grows increasingly unreliable. But to treat these disorders and to understand how we sense time's passage, researchers say they must stand back and see the brain as a complex network of circuits, some interlocking, some whirring away independently. This "network" approach to brain science "is a much more complicated problem" than asking what tasks are performed in individual regions of the brain, says Catalin Buhusi, a computer scientist-turned-brain scientist who now researches time perception at the Medical University of South Carolina.