Figure 3. Schematic drawing of the animal-holding device containing an anesthetized sockeye salmon.

A: frontal view; B: side view; C: water flow-through system mounted in the bore of the magnet during the magnetic resonance imaging experiment and the olfactory stimulus delivery system. The gill perfusion tube was fixed in the mouth of the fish. Odor stimulant water and AFW (artificial fresh water) water perfusion tubes were fixed in the right nasal cavity. coil, ¹H transmit/receive surface-coil (diameter: 5 mm); OSW, odor stimulant water; GPW, gill perfusion water; P, peristaltic pump.