#19 - Split Second Music Judgments

What can we deduce from hearing less than 1 second of music? Learn how accurately listeners can identify music genres from excerpts that are less than a quarter of a second long, and see how your brain does in a mini version of the experimental task. Our takeaways include how these sophisticated, split-second associations to music sometimes work against our better judgment.

References

• Mace, S.T., Wagoner, C.L., Teachout, D.J., & Hodges, D.A. (2012). Genre identification of very brief musical excerpts. Psychology of Music, 40(1), 112-128. https://doi.org/10.1177/0305735610391347

Song Excerpts

• Classical: Adagio for Strings (Barber), The Planets, Op. 32: IV (Holst), Trois Gymnopedies: I (Satie)
• Country: All I Want to Do (Sugarland), Everybody Wants to Go to Heaven (Kenny Chesney), 
• Jazz: In the Mood (Glenn Miller), Take Five (Dave Brubeck), So What (Miles Davis)
• Metal: Troops of Doom (Sepultura), Madhouse (Anthrax)
• Hip-hop: Whatever You Like (T.I.), What Them Girls Like (Ludacris), Got Money (Lil Wayne & T-Pain)

Resources

• The Record: Q1 2025 U.S. Audio Listening Trends
• TokChart.com
• Harmony Healthcare American Phone Usage and Screen Time Statistics

Chapters

• 0:00 Introduction
• 1:31 Can you name this tune?
• 4:04 Fast vs. slow auditory processing
• 7:08 Overview of the experiment
• 9:13 Try out the listening task
• 14:29 How accurately did participants identify the music genres?
• 16:40 Interactions with gender and formal music training
• 20:09 Takeaways for social media scrolling

Transcript

00:00: Hi there, it’s Brea and welcome to Instru(mental). As a millennial, I grew up in the 1990s and I have memories of choosing what music to listen to with  a method that is kind of defunct now. This was before there was music streaming services like Spotify, which launched in the United States in 2011, before Bluetooth became standard in cars in the 20-aughts, and even before the iPod debuted in 2001. It sounded something like this…

00:37: Yes, flipping through the radio, making lightning fast decisions about whether to listen to a station or not. I actually thought that radio listening was a timeworn, but now obsolete method of deciding what music to listen to, but in researching this episode, just to double check, I found a recent report by Nielson and Edison Research that suggests that the average adult in the United States spends 66% of their audio listening time each day listening to the radio. So, maybe flipping through the radio isn’t as defunct as I thought it was.

01:12: Regardless, this practice of making lightning-fast decisions about what to listen to actually reveals humans’ pretty amazing accuracy to identify music from less than one second of sound, even down to an ⅛ of a second. In case you’re a little skeptical, let’s try out some examples together.

01:32: We’ll start with some iconic examples, a little name that tune but from just one note or two. Take a listen, can you tell me what this song is from just the first note? [First clip] If you guessed Hard Day’s Night by the Beatles, then you are correct and you figured out the right answer in 3 seconds. Let’s try another, this next clip has just one note, and it’s less than half a second long so I’ll play it a few times [Second clip]. That second clip was the first note to Bohemian Rhapsody by Queen. And one more example, this clip is two notes long and I’ll play it twice again [Third clip]. It’s a little tougher, I know that a few iconic songs start with the bass. But, t hat third example was Seven Nation Army by The White Stripes. How’d you do with all three clips? Even from one note, if we’re really familiar with a song, we can figure out what music is being played without a lot of information, kind of like when we’re flipping through the radio.

02:43: Humans are actually very accurate at determining what genre of music is playing, even when we hear less than a second of sound, even down to a quarter or an eight of a second. Just how little music do we need to hear to identify a song’s genre, and what might these split-second determinations reveal about how our brains process music? Keep listening to find out more…

03:30: The research study at the heart of today’s episode was conducted by four researchers, Sandra T. Mace, Cynthia L. Wagoner, David J. Teachout, and Donald A. Hodges in an article that was published in the Psychology of Music academic journal. The reference is in the episode description if you want to check it out for yourself. The study they conducted and published in 2012 was built on prior research that revealed how quickly our brain is able to make relatively sophisticated judgments about music with less than 1 second of information.

04:05: When a sound is produced in our environment, the soundwaves are first picked up by our ears and go  through the outer, middle, and inner parts of our ear. Episode 13 of Instru(mental) goes over all of these details of the hearing pathway. Lots of dimensions of a sound’s signal like its volume, timbre, and pitch are then converted from physical energy (like, membranes or bones or little hair cells in our ear are vibrating), this physical energy is converted into electric energy in the inner ear’s cochlea. And the electric signals are sent into our brainstem and then the brain via the auditory nerve.

04:44: Part of that auditory signal is processed in our brainstem, and the fastest, most immediate thing our brain listens for in the auditory signal is whether the sound indicates we may be in danger. If a sound’s onset is unexpectedly loud or sudden, then the sound may trigger a startle response that we can register in 5 or 6 milliseconds, with a millisecond being one thousandth of a second. If that auditory startle reflex gets activated, then we might actually have a jump scare in our body in as little as 14 to 22 milliseconds after the sound is heard. Our brain is definitely looking out for us, and it’s ready to get our bodies moving in like 2 hundredth of a second after a sudden, loud, or really unexpected sound happens. This is a really fast response time to sound.

05:36: Even quote “slower” auditory processing still happens extremely quickly. It’s called the “slower” pathway because the auditory signal moves up from the brainstem, to the thalamus, to the auditory cortex , and then to the auditory association areas of the cortex. Each part of the brain that the auditory signal moves between adds additional layers of understanding about what the sound is and where it’s coming from. Prior to the main  study we’re covering today, previous music science researchers had done studies whose results suggest that participants can accurately determine whether instrumental music is happy or sad after hearing only a half second of music. In a different study, participants were consistently being able to judge whether a song was in major or minor mode, whether it was slow or fast, and other musical dimensions in as little as 100 milliseconds, which is one tenth of a second. A third prior study even found that hearing just a quarter second of music can give people clues about how emotionally expressive or  moving a song is. This is all to say that we as humans can tell a good amount of information from music after hearing very little of a piece.

07:09: The study we’re going over today decided to look at how well people are able to identify different music genres after hearing a clip that was one second or less. And, these researchers wanted to know whether listeners’ past music experience or gender influenced how accurate they were in correctly identifying genres.

07:30: Specifically, the researchers tested whether participants could accurately identify five musical genres: classical, jazz, country, metal, and rap/hip-hop. Each of these five genres was represented by about 10 songs that were prototypical for that genre. So for example, all of the country songs had singers with that typical vocal twang,  the hip-hop songs featured drum machines, and the jazz songs all had a prototypical rhythm section. Once they had all of the songs for all the genres picked out, the researchers created 200 excerpts that participants would listen to and try to identify.

08:11: Why 200 excerpts? Because each song was randomly sampled to get four different clips of different, but still very short lengths. The longest clips were 1000 ms long (which is 1 second), followed 500 ms (which is half a second long), next was a clip that was 250 ms long (or, a quarter of a second), and the shortest clips were 125 ms-long (which is about an eight of a second). So there were 200 excerpts because participants listened to clips from 5 musical genres, each represented by 10 songs, and each song generated 4 different clips lengths. 5 x 10 x 4 equals 200 excerpts. The article itself listed all 50 songs that were used in the experiment, which was really helpful, because it allowed me to create my own versions of the musical excerpts so we can try out an unofficial version of the experiment for ourselves right here on the podcast.

09:14: We are going to try out our own little listening test from the clips I created, from the actual songs used in this experiment. This is an unofficial setting, but if you’re able to listen somewhere quietly and with focus, this will help a lot because, again, these are very brief excerpts. I’m also going to deviate from what the researchers did and play each clip twice to give you a little bit better of a chance at guessing each genre. This is all in good fun, so we don’t need to follow the experiment procedures exactly.

09:47: Here’s how our experiential will go. We’re going to play five rounds, where the first round starts with the longest clips (which are a second long) and the last round will have all of the shortest clips (which will be an eighth of a second long). I’ll play each clip twice, pausing after each genre’s clip for two seconds so you can guess whether you just heard a classical, jazz, country, metal or hip-hop excerpt. At the end of each round, I’ll tell you the correct order of clips for that you just heard, but I’ll be randomizing the order of genres in each of the five rounds. Ready? Okay, let’s get started.

10:27 This is round one, so you’ll be hearing the 1 second  long clips. Here’s the first clip.

11:06: Pretty easy, I’d think? From first to last, those musical genres were jazz, classical, rap, country, and finally, metal excerpts.

11:19: For round two, you’ll be hearing the 500 ms clips, which are each half a second.

11:51: I’m gonna guess you were still feeling pretty accurate. Those five clips, in order were country, metal, classical, rap/hip-hop, and jazz.

12:04: Round three is gonna get a little trickier. Each clip will be 250 ms long, which is a quarter of a second. 

12:35: How’d that go? For round there, the clips from first to last were rap/hip-hop, jazz, country, classical, and metal.

12:47: And finally, Round four has clips of 125 ms, which is only an eight of a second so buckle up. Here we go.

13:20: For that last round, the clips were classical, country, metal, jazz, and hip-hop. 

13:28: Hey, it’s post-editing Brea here. Sorry, there were only four rounds, I had a script mix-up. Okay, back to the podcast.

13:36: Did you still get most of them? When I tried this out with my husband, he surprised himself with how accurate he was. I think he only missed one, but he felt pretty shaky on a handful of them. But, despite not feeling super confident, there was some intuition he had that led him to the right answers, way more than chance. If someone had been guessing at chance level, then you’d only be correct 20% of the time.

14:04: If you had been a participant who consented to take part in the study, then the listening conditions would have been a little different. You would’ve been in a classroom setting, listening to these excerpts over sound speakers, writing down your genre guesses within 4 seconds of hearing each excerpt, after hearing it only once. And, you would have had to listen to 200 excerpts, although each one was randomized by length and genre.

14:31: According to the official study’s results, who were the participants, and how did they do? The participants for this study were 347 college undergraduates, mostly between 18 and 24 years old and this sample was 37% male and 63% female. Additionally, the researchers asked participants whether they had at least 3 years of formal musical training, and 72% of participants were trained musicians.

15:00: Over all 200 excerpts, the participants were extremely accurate! They identified the correct genre 76% of the time for all five genres and all excerpt lengths. So, way above chance level, which would have been 20% correct if people were just guessing. When participants heard the 1 second excerpts, they got the genre correct 89% of the time, and at half a second they were correct 83% of the time, still very accurate. When they heard only a quarter of a second of a song, participants were correct 77% of the time, and finally when participants only heard one eighth of a second  of a song, they got the genre correct 54% of the time, more than twice as accurate as chance level. I’m curious how those trends compare with how you did. 

15:50: Between the five musical genres, there were differences in how accurately participants deduced the correct answer. Both metal and hip-hop had a huge jump in accuracy between the eighth of a second and the quarter of a second clips. When participants heard only an eighth of a second of metal or rap, they were the least accurate, only getting it right about 40 to 50% of the time. But, as soon as participants heard at least a quarter second of those genres, they correctly identified the 80% or more of the metal and  hip-hop excerpts.

16:24: For the classical genre, the participants needed to hear at least a half second of those excerpts to get to at least 80% correct. And, finally, participants needed to hear the longest, 1 second clips of both jazz and country music to reach that 80% correct threshold. 

16:40: The researchers also wanted to understand if participants’ gender or formal musical training made them more accurate in identifying genres. For genre, there was no significant difference in men or women in identifying all five genres as a whole, but there were some curious interactions between gender, genre, and excerpt length.

16:55: Specifically, men were significantly more accurate in identifying metal excerpts than women, especially at an eighth of a second long and men were significantly more accurate in identifying jazz clips that were a quarter of a second long. For women, they were significantly more accurate when identifying hip-hop clips that were a quarter of a second long. 

17:16: When taking formal music training into account, there was no main effect in overall genre accuracy. So, people with at least 3 years of formal music training had no advantage in identifying all five genres than the non-musicians. However, participants with formal music training were significantly more accurate when hearing most of the jazz excerpts and the one-second long classical excerpts, while participants without formal music training were significantly more accurate in identifying the shorter  hip-hop excerpts. In addition, all participants were the most accurate in identifying whichever of the five genres they rated as their favorite, when compared to their accuracy for the other four genres. 

18:01: In their discussion, the researchers propose that their results may be explained by the Preference for Prototypes Theory, which says that people classify incoming information based on their pre-conceived prototypes of what that category typically means. So, maybe in our quick listening test, you heard a certain vocal twang to decide that one of the clips was country. Or, maybe you heard a harsher, more distorted instrumental timbre that helped you categorize a metal clip. The Preference for Prototypes theory would also predict that you were more accurate classifying stimuli that fell into categories that you liked more, and have more experience with because you like it more so we’re going to spend more time listening to those types of songs.

18:48: So, if your favorite genre of the five to listen to is hip-hop, there’s a good chance that you were better than average in identifying those clips. Anecdotally, the researchers commented that many of their study participants would identify the actual  specific songs and artists from which the excerpts were derived. If you’re curious about which songs I used for the excerpts, you can check those out the episode description.

19:27: So, to recap what we’ve covered today, our auditory systems are able to make pretty accurate judgments of our sonic environment on about a quarter second of information. Across the five musical genres tested, people correctly identify between classical, country, jazz, metal and hip-hop music 76% of the time, when they have one second or less to go off of. Just from those little slices of sound, our central nervous systems are capable of activating all sorts of other associations, emotions, memories, and even get our body moving if it determines that the sound might be associated with an unexpected, dangerous thing. 

20:10:  Alright, let’s talk takeaways. How can the results from this study apply to our everyday lives? Even though we might not be scrolling through the radio on a daily basis now that a lot of people use streaming services, there is another kind of scrolling we’re probably doing even more today: social media scrolling. In the last few years, short form video content like TikTok or Instagram Reels is everywhere.

20:36: In these social media formats, our instantaneous music judgments as we flip between videos is also interacting with the imagery that we’re seeing on the  screen. Let’s do one more listening example, this one is half a second long. If you just heard this excerpt, do you think you’d pause an extra couple seconds  to watch the video, or would you instantaneously know that you don’t want to watch this video?

21:02: That clip is from a piece of music called Monkeys Spinning Monkeys, here’s a bit of a longer clip.

21:18: Monkeys Spinning Monkeys has been meme-ified to be associated with videos that are fun, silly, and maybe have something cute like a baby animal. Since being released in 2019, that song has been used in over 30 million videos, according to TokChart.com, which is one website that tracks what music is trending on social media platforms around the world.

21:40: I didn’t find any specific studies on music as a meme for short-form videos, but I’m so curious how the split-second recognition and associations that can get activated when we hear just one second of music might be influencing whether or not we end up watching a video. According to a report by Harmony Health, about half of Americans want to cut down on their phone usage, and 79% of Americans say social media is their most addictive type of phone app.

22:11: In today’s social media age, I think it’s important to examine not just how amazingly sophisticated our musical judgments can be, but also take note of when those snap judgments might be pulling our attention into something that isn’t aligned with how we actually want to   spend our time, or making us lose track of time in an unhelpful or unhealthy way. When I’m finding myself aware that I’m getting stuck in social media, sometimes I’ll make whatever content I’m engaging with less appealing to my senses.

22:41: I do this by having a shortcut on my phone that automatically turns my screen grayscale, and it’s really striking how less interesting and boring your phone feels when there’s no more color. I feel like turning your phone on mute might also be a sonic equivalent to my grayscale shortcut. But,  I know that content creators automatically caption their videos as well because people watch so many videos with sound off. But, every tip can be helpful, along with our awareness that we do have a choice when it comes to how we consume media. Even just knowing that music’s pull starts at the split-second level can help us make a more conscious choice.

23:22: Alright, thank you so much for taking a listen to Instru(mental). Our soft launch is complete! We’re going to take a couple of weeks off to regroup and prep the next 10 episodes, which will be debuting in mid October  2025. If you are enjoying what you’re hearing, take a minute to give the podcast a positive rating or share your favorite episode of Instru(mental) with someone you know who would also enjoy listening. See you in a few weeks…