The song was composed by Kyohei Tsutsumi（筒美京平）and written by Reiko Yukawa（湯川れい子）. It struck me as one of the quintessential aidoru songs for the early 80s as the melodies were slowly transitioning from the electric guitar to synthesizers. "Sentimental Journey"kinda shows that slow transfer to me.
Here is an older Matsumoto hoofing it with the zany comedic duo The Tunnels as she performs her signature tune. According to an anecdote from J-Wiki, the production staff discovered that her voice was relatively low for an aidoru although she was still groomed as such. One of them threw her a tape of the American female vocal group The Ronettes and told her to study their vocal style in preparation for her debut.
Since her aidoru days, Matsumoto has also gone the actress/TV personality (tarento) route, mostly in the latter category. But once in a while, she has popped up on stage to perform "Sentimental Journey". Several years ago, she teamed up with other former aidoru-turned-parents Yu Hayami（早見優）and Chiemi Hori（堀ちえみ）to form a "mamadoru (mama aidoru) unit"called Cutey Mommy.