Earlier this year, Malcolm Young was forced to leave AC/DC due to dementia. In a new interview, singer Brian Johnson said the guitarist's influence through the band runs incredibly deep.

"He was the man that started the band," he tells NewsChannel 9 of Chattanooga, TN. "He was the one that was behind AC/DC. He was our spiritual leader. He was our spitfire."

Johnson was in Chattanooga to raise funds for Highway to Help, a venture of his Fifty Plus Racing team that raises money for Alzheimer's disease research. He said that it's all part of "that desire to fix something that's unfixable," and he admits that his optimism is too often tempered by reality.

"You just expect that they are going to get better," he continued. "You think there's going to be a pill that's going to fix them. I don't know, you think there's going to be a miracle and of course, one day you wake up and realize there isn't and it hurts."

AC/DC are set to release 'Rock or Bust' on Dec. 2.

AC/DC Discuss Malcolm Young’s Absence