Crazy day at the salon? Nope, just one of the first circular detectors for brain imaging - known today as positron emission tomography (PET) scanners.
The Instrumentation Division at Brookhaven built this detector array in the 1960s to identify small brain tumors by analyzing the decay of radioactive material injected into the bloodstream and absorbed by the tumor. In the 1970s, Brookhaven researchers found a way to reconstruct the detector data into an image of the working brain. Today, all PET machines use circular detector arrays, though they tend not to look as cool as the one in this photo.