Complex sentence: However, in recent years some researchers have included injuries in which structural damage has occurred under the rubric of concussion and according to the National Institute for Health and Clinical Excellence definition, concussion may involve a physiological or physical disruption in the brain's synapses.
Split into simpler sentences: However, in recent years researchers have included injuries in which structural damage does occur under the rubric of concussion. According to the National Institute for Health and Clinical Excellence definition, concussion may involve a physiological or physical disruption in the brain's synapses.