For decades scientists have been interested in the migration patterns of salmon. Recently scientists have discovered that alterations in salmon swimming patterns from the re-direction of streams and rivers has led to an increase in bruising on the fish. In fact, these salmon are found to have signs of brain injury.
The symptoms of brain injury were discovered when scientists began monitoring the effects of dams along salmon runs to detect the amount of force it put on the migrating fish. Scientists used everything from dummy fish containing accelerometers to even embedding sensors in live fish. These methods allowed scientists to detect brain injury in salmon.
This is important for the medical community because it mirrors the way that traumatic brain injury is detected in humans. Several years ago a researcher at the University of Florida experimented with testing for evidence of the breakdown of proteins found in cell membranes in order to assess traumatic brain injury in soldiers. The theory behind this method is that cell damage releases enzymes that break this specific protein into small compounds.
So when testing for traumatic brain injury in salmon the researchers applied a similar nonlethal test to the one used in humans that would examine spinal fluid for evidence of the breakdown products. Although more challenging in fish, the results are positive in the medical detection of traumatic brain injuries in both humans and salmon.