This is a guest post by Scott Miles, PhD, – Chief Visionary Officer and President at Secret Chord Laboratories, a music-tech company that uses insights from neuroscience and artificial intelligence to “help creators make stronger, more objective artistic and business decisions.” Here, he uses their dopr technology to identify the song’s shifts in rhythm and explains how that helped the song become a huge success.
When Olivia Rodrigo dropped her first single, ‘drivers license’, it immediately became a breakaway success. Millions of listeners streamed the song, helping it reach the top of many charts worldwide.
Why did this song become so popular?
Maybe people identified with the heartfelt sentiment of loss that the song expressed. Maybe people jibed with the coming-of-age theme, marking our shared experience with a rite of passage.
We couldn’t help but notice the sheer mastery in the song’s use of rhythmic surprise – specifically, the contrastive rhythmic surprise among the different sections of the song.
We have conducted extensive neuroscience research into how the structure of music leads to a dopamine pleasure response in the brain. One of the effects we have identified is called contrastive surprise. In our 2017 paper in Frontiers in Human Neuroscience, we reported this effect in harmony—successful popular songs tend to use contrasting levels of chord rarity in successive sections, such as in a verse and in the chorus that immediately follows it.
Harmony is just one feature, however, that uses contrastive surprise to lead to a dopamine pleasure response in the brain. We have found that what we call familiar surprise leads to optimal music enjoyment, which can be measured in terms of other aspects of music, such as melody, rhythm, timbre, texture, and dynamics.
Melody has rhythm too
When talking about the contrastive rhythmic surprise in ‘drivers license’, it is important to recognize the rhythm component of the melodic line in popular music.
When thinking about melody, it is common to focus on aspects having to do with pitch—such as register, contour, or range. An example of a surprise in pitch would be a minor third interval in a major song, or shifting up an entire octave in the third chorus of a song. Melodies also have rhythm, however, and the success of many popular songs has been attributed to very specific patterns of rhythm within melodies.
Contrastive Rhythmic Surprise and ‘Melodic Math’
The most famous conscious manipulation of rhythmic patterns within melodies of popular songs is known by the term ‘Melodic Math’, coined by prolific pop songwriter Max Martin.
In interviews, Martin has sometimes talked about ‘Melodic Math’ as if it is a precise science, but the exact nature of it is not widely known. One clear aspect is that it involves the juxtaposition of song sections featuring many short notes with sections featuring fewer, longer notes. This makes sense to us at SCL, because the result is an effect of contrastive rhythmic surprise, shown through our neuroscience research to lead to a dopamine pleasure response in the brain.
Contrastive Rhythmic Surprise at work in the melody of ‘drivers license’
Putting aside all the cultural aspects of the song, there is a lot happening musically in ‘drivers license’ that is consistent with what we have found to lead to enjoyment in popular music. As mentioned above, the song features contrastive rhythmic surprise, implemented through the use of several internally consistent melodic rhythm patterns that change with each successive song section.
Let’s take a look at how this happens in the song itself.
Section 1 Rhythm – about eight notes per bar, alternating short and long notes
‘drivers license’ opens with a melodic rhythm of about eight notes per bar, with alternating short and long notes. This pattern of accents is also known as iambic, as in the style of poetry used in Shakespearian plays. It somewhat mimics the accent pattern of natural speech and gives the opening section a conversational, matter-of-fact delivery that sets up the premise of the story in the song (“I got my driver’s license last week… just like we always talked about…”).
Section 2a Rhythm – lines starting with even eighth notes
As the tension builds with the introduction of the second section, the song moves to a more even rhythm of repeating eighth notes. This is in contrast to the iambic pattern of the previous section.
The shift away from the opening section’s iambic pattern provides contrastive Rhythmic Surprise. The use of more uniformly emphasized, spaced out notes also matches the tone of the pleading argument being made in the lyrics. It is a clear attempt to get across a nuanced and emotionally charged point (“I know we weren’t perfect but I’ve never felt this way for no one…”).
Section 2b Rhythm – Triplets
This section builds tension with the introduction of a new triplet rhythm in the melody. Just as the listener has gotten used to the regularity of the evenly distributed eighth notes of the first part of the section, the rhythm is once again changed, this time the most drastically, to feature triplets—three eighth notes counting as one quarter note.
The ‘triplet flow’ has famously been used increasingly throughout the past decade or so in hip-hop music to add rhythmic flavor to melodic lines, being traced back to artists such as Chuck D and the Migos.
In recent years, the ‘triplet flow’ has expanded far beyond hip-hop, however. Artists such as Ke$ha and Taylor Swift (both of whom, interestingly, have worked with Max Martin) have also started to introduce the ‘triplet flow’ into their pop songs. Here, ‘drivers license’ introduces triplets quite tastefully to build tension in the brief section leading up to, and ending with, the song’s refrain (“you-said-for / ev-er-now / I-drive-a / lone-past-your…”).
Bridge Rhythm – Alternating bars of four notes and seven notes each
In our research, we have found that the bridge section often features the most surprise—whether it is harmonic surprise or surprise in other features—of any section in a successful song. This is likely due to the fact that the listener has heard many of the repetitive aspects of the song several times, and is ready to hear something new. The bridge is used as a way to ‘clear the palette’ of the listener, before returning to a familiar chorus or refrain. The return of the familiar section is that much more satisfying after hearing such a distinct bridge.
In the bridge of ‘drivers license’, the melodic rhythm changes once again, this time to introduce a pattern of alternating bars of four, spaced out iambic notes (“Red lights, stop signs…”), and seven shorter notes (“I still see your face in the…”). This brand-new rhythmic pattern features its own internal contrastive rhythmic surprise. The result is a dramatic effect, and the relative simplicity in the melodic rhythm is counterbalanced with a gospel-like choir harmony added to the melody.
Return to Refrain Rhythm
In the wake of the bridge, the song returns to the relatively familiar section with triplet rhythm in the melody. The relative sparseness of the soundscape in this final refrain section counterbalances the more complex rhythmic pattern. The familiarity of this pattern helps to resolve, for the listener, the tension built up during the bridge section.
With this tension resolved, the song comes to a quiet end with a return to a more familiar section. The effect of this return on the listener, after the departure of the bridge, is like that of an auditory roller coaster gently pulling back into the gate after going through several rhythmic twists, turns, and drops.
– Secret Chord Laboratories’ dopr platform is now in beta – you can sign up here.