Neurologist Francis Jensen examining a teenage patient. Jensen decided to study the teenage brain when her own sons became teenagers. Now Jensen lectures to teens and parents about how teenagers' brains are different.
As we age, our muscles deteriorate, and they don't repair as quickly as they used to. But the good news is that exercise and weightlifting can still make muscles stronger.
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In order to officially diagnose a patient with a disorder, doctors use the criteria checklists established in the DSM. The DSM 5 is pushing to use scales of severity instead of a present/absent checklist of symptoms.