The Spinal Cord

The caudal part of the CNS is the spinal cord (Fig. 1). Sensory impulses enter through its 31 paired spinal nerves, and sensory data processing begins. Messages flow up over modality-specific tracts, fast and direct or slow and indirect, to higher cord regions and the brain: to the medulla, pons, cerebellum, midbrain, and thalamus. The thalamus integrates this information with other input and in reciprocal association with the cerebral cortex. In due course, or on its own, commands from the cerebral cortex and certain brain stem regions flash down to spinal motor neurons and nearby local-circuit neurons. These small cells regulate the motor neurons and integrate their activity from one level to another and across the midline. Although its intrinsic spinal activity is monitored by higher centers, the spinal cord draws up swift and complex reflexes on its own, playing out movement programs (like walking or running) as if from a computer-numeric-control tape.

Breaking Bulimia

Breaking Bulimia

We have all been there: turning to the refrigerator if feeling lonely or bored or indulging in seconds or thirds if strained. But if you suffer from bulimia, the from time to time urge to overeat is more like an obsession.

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