The Ways Rhythm Shapes Our Lives (2023)

My husband reads to me every night in bed before we go to sleep. With our special bear, Oatmeal, tucked in between us and listening too, this is a wonderful way to end the day and is a quotidian highlight. We deliberately choose books that are familiar — oft-read children’s classics by E. B. White and the Harry Potter series make frequent appearances — so I do not worry about missing something important when I drift off. I have noticed that after some time — it can be as little as a few minutes if I am especially tired — the meanings of the words are gradually eclipsed by the sounds. I begin to hear sounds and rhythms instead of words and story, and the waxing and waning of the accents and stress patterns become a calming, lulling, treasured experience that soothes and resets me after a long day.

Why do we care about rhythm? It connects us to the world. It plays a role in listening, in language, in understanding speech in noisy places, in walking, and even in our feelings toward one another.

Rhythm is much more than a component of music. Nevertheless, music is probably what first comes to mind when we hear the word rhythm: drumming, jazz, rock and roll, marching bands, street performers with wooden spoons and five-gallon buckets, drum circles, time signatures, stomp-stomp-clap — we will, we will rock you — adventures on the dance floor, beatboxing, incantations, mantras, and prayers. Beyond music, we experience the rhythmic changes of the seasons. Some of us have menstrual cycles. We have circadian rhythms — daily cycles of mental and physical peaks and troughs. Frogs croak rhythmically to attract mates and change their rhythm to signal aggression. Tides, 17-year cicadas, lunar phases, perigees, and apogees are other naturally occurring rhythms. Human-made rhythms include the built world — street grids, traffic lights, crop fields, mowed designs in baseball diamond outfields, the backsplash behind the kitchen counter, spatial patterns in geometric visual artforms.

Maintaining rhythm is almost a biological imperative for some of us. My musician husband can get infuriated if we are playing together and I stop in the middle of a song. He needs to keep the pulse going. I have my own hiking version of this imperative. I need to keep moving no matter how tired I get, one foot in front of the other, even if I slow way down, or essential energy just drains away.

Rhythms in the brain have been called out as a basis for consciousness itself.

Music and rhythm are rooted in every known culture. What parent does not use rhythmic rocking to soothe a crying baby? The repetitive sounds and silences that comprise rhythmic patterns make dancing possible, aid in the memory and reproduction of music, and facilitate group singing, playing, or drumming. Rhythm has been used for millennia to tie societal members together — the chants of a religious order or the cadence calls of military ranks are just two examples. Poetic works thousands of years ago, such as those of Homer, were chanted or sung with rhythm serving a mnemonic function. Repetitive or complex work engenders rhythmic accompaniment, in some cases to break the monotony, in others to actually help you perform the work better. Workers performing hard labor like rock breaking chant to keep their sledgehammers swinging in rhythm. Postal workers in Ghana hand-cancel stamps with a distinct rhythm. Rug weavers in Iran use chants with a complex musical structure to communicate weaving patterns to their co-weavers. All musical systems and styles have organizational rhythmic motifs. Indeed, the very universality of rhythm is a strong argument for the existence of biological processes governing the perception and production of rhythm. Rhythms in the brain have been called out as a basis for consciousness itself.

Language probably does not immediately come to mind when we think of rhythm. You might have had a high school literature class where you learned about prosodic feet — iambs, trochees, and anapests. But outside the context of poetry, we rarely think about speech having a particular rhythm. After all, we are likely to say “Oy Bill — you ready yet?” Not, “Hey there Bill,/do you think/it is now/time to go?” so that it conforms to dactylic tetrameter. What about rhythm and reading? Here, too, we are unlikely to associate rhythm to reading unless we are reading poetry. In fact, rhythm is a necessary ingredient of linguistic communication itself.

Rhythm can be viewed through the lens of shorter and longer time scales. Speech has phoneme-, syllable-, word-, and sentence-length rhythmic units, each unfolding at their own rate. We understand that speech comes in different sized units — the sound an individual letter makes, the phoneme, at one extreme, and the slowly rising and falling loudness and pitch contours that unfold over the course of a sentence or group of thoughts on the other. This latter one is the nighttime reading rhythm I fall asleep to. These entwined elements of speech constitute rhythms that must be sorted by our sound minds. We can try to focus on the slow parts of speech (say, the fluctuating pitch of the voice) and ignore the fast (the vowel and consonant sounds that convey the meaning of the words) or vice versa. But this is usually not possible and rarely desirable.

This temporal hierarchy is at work in music too. Music is a mix of slow phrases, steady beats, sustained notes, rapidly changing notes, trills, and drum crashes. Entwined temporal structures are in environmental sounds as well — when walking through the woods, we simultaneously hear slow footsteps, the unfolding crunch of leaves underfoot, and the rapid snap of a twig. Much as sound units come in different lengths, brain rhythms come in different speeds. Subcortical structures are equipped for microsecond timing while the cortex is better suited to integrating sounds over a longer time scale.

Brain rhythms can be measured both when at rest and when performing an activity. When listening to speech, there are fast brain rhythms that entrain to the fast phonemes, the near instantaneous consonant sounds. Middle-range rhythms in the brain track the rate of syllables. Slower brain rhythms correspond to the slow oscillations of phrases and sentences. Similar nested brain patterns are active when listening to music.

We’ve all heard him. The beginning piano player. The “Eensie Weensie Spider” and “Frère Jacques” plinking hesitantly out of the piano. Usually getting the notes right is paramount to a beginner; hitting the right keys trumps hitting them at the right time. It is heartwarming to listen as our child plays (mostly) correct notes at wildly incorrect times. What goes on in the brain when we hear music being played on beat or off beat?

Imagine a metronome ticking at about 144 beats per minute (bpm). Popular songs in this range include Blondie’s “Call Me,” the Beatles’ “Back in the USSR,” and the Rolling Stones’ “(I Can’t Get No) Satisfaction.” It’s a fast, allegro rate. Measured another way, these songs have about a half second between their beats. If we play a conga drum by itself at this rate and record brain waves to it, we will see neural activity repeating every half second (boom, boom, boom, boom, or “one, two, three, four”). But what does the brain do if you listen to the conga drumming along to a song that matches this beat? The brain produces a new rhythm! In addition to a response peak every half second (where musically speaking the “ones” are), you see another, smaller peak halfway in between (1 and 2 and 3 and 4 and; “FLEW in FROM mi-AM- i BEACH”). The brain has worked out the strong/weak pairs comprising the song’s meter.

If our rhythmic expectations are violated, our brains behave in a different manner because of our inherent internal sense of rhythm.

This tells us the brain entrains and reinforces both explicit and implied rhythms in the music. This extra rhythm in the brain wave does not occur when the song is deliberately misaligned with the conga beat. A similar example of the brain creating a beat comes from Brainvolts alum Kimi Lee, who found that the fundamental frequency of an identical speech sound is enhanced when it occurs on the “1” in a four-beat sequence. The sound mind’s response to a drumbeat is deeply shaped by its aural context. Rhythmic organization operates automatically when we listen to sound. If our rhythmic expectations are violated, our brains behave in a different manner because of our inherent internal sense of rhythm.

Imagine the familiar rhythm “Shave and a haircut, two bits” and tap it out on a table with your finger. Did you tap seven times? Now imagine it again and tap your foot to it. Did you tap seven times again? Or fewer? For me, when I tap my finger on a table, I tap to every note (ignoring the rests). When I tap my foot or snap my finger along to music, I typically tap or snap to the beat (or pulse) of the song, not every note. When I tap my finger on the table, hitting the “sounds” and ignoring the “silences,” I am tapping out the rhythmic pattern — I am keeping track of how long or short each note is and where the pauses occur. When I tap my foot, I tap four times, to the underlying beat or pulse (see the rhythm pattern below), which in this example includes a silent beat. Music has both a pulse and a rhythm pattern, notated by time signature and note/rest durations, respectively.

Before I began studying rhythm, if you had asked me about the skills involved in tapping out rhythmic patterns versus tapping out the beat, I would have said, “You’re probably either good at both or not so good at either.” If someone can tap to a beat, she can also tap out a rhythm pattern, right?

Wrong. There are multiple rhythmic intelligences. You cannot predict how someone will perform one rhythm task by how they perform a different rhythm task. This was first noticed in extreme cases where a person with brain damage could be impaired in one sort of rhythmic ability but not another. We have since learned these distinctions are fundamental to how the system works: we see dissociations between rhythm skills in all of us, confirming the idea that “rhythm” is not an all-or-nothing ability, and more intriguingly, our proficiency executing one type of rhythm or another bears on our language skills. Both beat-keeping and rhythm-pattern skills predict language development and reading ability; however, only rhythm-pattern ability has a bearing on understanding speech in noise, as we will see in a moment.

Rhythm pattern skills are associated with slower brain rhythms (seconds), while beat-keeping skills are associated with faster brain rhythms (milliseconds and microseconds). Phonemes, syllables, and sentences range from microsecond to millisecond to second timing, respectively. Brain rhythms can predict language development in infants and children. Brain rhythms can also determine a person’s strengths and bottlenecks related to language and the ability to make sense of an auditory scene while listening in noise.

Rhythm is tied to language. Children who recognize differences in rhythm patterns and tap to a beat learn to read and spell more easily. Several beat-keeping skills are impaired in older children with dyslexia. We have found a link between beat keeping and language development in adolescents and in children as young as three years old. What is the connection between rhythm skills and what might appear to be unrelated skills like reading and writing?

There really is rhythm in language, beyond the rhyming of poetry. It is inherently a part of pronunciation. Rhythm matters, even in single words. “Record,” “contrast,” “project,” and “produce” can be either nouns or verbs depending on which syllable is stressed. Running speech also has rhythm. A YouTube search for “drumming to speech” will uncover some nice examples; a personal favorite is the one with the scene from the Gene Wilder Willy Wonka movie. The video sho