I believe chills/goosebumps are more mystical than what can be proven by 'science'. I believe that the connection that creates this stimulation is from soul to soul - it's pure truth and the brain merely makes one aware of the spiritual connection that is happening.
I got this sensation when I was recording Josephine's vocals for Be Love, the opening piece of music for Perfect Freq journey/album. In that moment, I realised that Josephine was the most perfect vocalist to feature on the project.
Close your eyes, and listen to the whole song, and see if you get goosebumps at any time throughout the music. If you do, note the moments and respond to this blog post with your experiences.