The arbitrator will consider the neutral physician’s findings conclusive with regard to the physical condition of the player and the extent of an injury at the time of his examination by the neutral physician. The arbitrator will decide the dispute in light of this finding and such other issues or defenses which may have been properly submitted to him. In cases in which the player is alleging that he suffered a closed head injury or concussion with resulting cognitive deficit, somatic symptoms and/or other concussion symptoms the report of the neutral neuropsychologist shall be considered conclusive with regard to the player’s cognitive functioning and other objective findings as well as the extent of the injury at the time of the examination.