The first<unk>  technique ever is the so-called 'human circulation balance' invented by Angelo Mosso in the 1880s and able to non-invasively measure the redistribution of blood during emotional and intellectual activity. Then, in the early 1900s, a technique called pneumoencephalography was set. This process involved draining the cerebrospinal fluid from around the brain and replacing it with air, altering the relative density of the brain and its surroundings, to cause it to show up better on an x-ray, and it was considered to be incredibly unsafe for patients (Beaumont 8). A form of magnetic resonance imaging (MRI) and computed tomography (CT) were developed in the 1970s and 1980s. The new MRI and CT technologies were considerably less harmful and are explained in greater detail below. Next came SPECT and PET scans, which allowed scientists to map brain function because, unlike MRI and CT, these scans could create more than just static images of the brain's structure. Learning from MRI, PET and SPECT scanning, scientists were able to develop functional MRI (fMRI) with abilities that opened the door to direct observation of cognitive activities.
History of neuroimaging
History of neurology and neurosurgery
History of psychotherapy
History of psychosurgery
History of pathology
History of neuroscience
History of dermatology
History of cardiopulmonary resuscitation