We often talk about optical illusions that trick our eyes, but have you ever thought about illusions that can fool your ears? Can you really trust what you hear? Let’s explore some fascinating audio illusions that might surprise you!
Imagine listening to someone say “Bar Bar Bar Bar Bar Bar.” What do you hear? Most people hear “Bar Bar Bar.” But what if you see a video where it looks like the person is saying “Far Far Far”? You might actually hear “Far Far Far,” even though the sound hasn’t changed at all! This is called the McGurk effect, where what you see can change what you think you’re hearing. Try watching different videos and see how the sound seems to change based on what you see.
Here’s another fun experiment: count how many times you see a circle flash on the screen. Did you count two flashes? Many people do, but if you watch without sound, you’ll notice the circle only flashes once. This shows how sound can change what we think we see.
Now, let’s try something with your friends or family. Listen to two tones and decide if they go from low to high or high to low. Write down your answers and compare them with others. You might be surprised to find that everyone hears something different! This is called the Tritone Paradox. The tones have both high and low frequencies, but our brains choose which one to focus on. This choice can depend on where you grew up and the language you speak.
Listen to a tune that seems to climb higher and higher. Now, play the same clip again. Does it still sound like it’s climbing? This is the Shepard tone illusion. It uses multiple sound waves that rise in pitch, while one quickly drops an octave. Our brains don’t notice the drop, so it sounds like the tune is endlessly climbing.
These audio illusions show how complex our hearing can be and why music can have such a powerful effect on us. If you’re curious about how music affects our minds, check out our new episode on ASAP Science. You might even find out if music can save your life!
So, do you still trust your ears? If you have questions or want to share your thoughts, feel free to comment or connect with us on social media. For more cool science videos, subscribe to our channel!
Watch a series of videos where the audio says “Bar Bar Bar,” but the visual shows a person mouthing “Far Far Far.” Pay close attention to what you hear. Discuss with your classmates how your perception changes based on the visual cues. Try creating your own video to demonstrate the McGurk effect to others.
Participate in an activity where you watch a video of a circle flashing on the screen. Count the flashes with and without sound. Compare your results with your classmates. Discuss how sound influences your visual perception and why this might happen.
Listen to a series of tritone pairs and decide if they ascend or descend in pitch. Record your answers and compare them with your classmates. Discuss why different people might hear the same tones differently and how factors like language and culture can influence perception.
Listen to a Shepard tone clip that seems to endlessly rise in pitch. Play it multiple times and describe your experience. Discuss with your classmates why the tone seems to climb continuously and how this illusion is created.
Watch a video or listen to a podcast about how music affects emotions and the brain. Share your thoughts on how music influences your mood or helps you in daily life. Create a playlist of songs that evoke different emotions and discuss why you think they have that effect.
Here’s a sanitized version of the provided YouTube transcript:
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Many of us have become quick to catch illusions that trick our eyes, but how often do you consider the illusions of the ear? Are you really able to trust your ears and the things they hear? For example, listen to Greg speaking: “Bar Bar Bar Bar Bar Bar.” What do you hear? If you heard “Bar Bar Bar,” you’d be right. But how about now: “Bar Bar Bar Bar Bar Bar ch”? Did you hear “far far far” this time with an “F”? Except you didn’t. In fact, the audio didn’t even change between the two videos. Strange as it may seem, what you hear depends on which video you’re looking at. Go ahead, take turns watching each video and see how the sound morphs. This is a perfect example of something called the McGurk effect, which shows how our visuals can alter what we believe we’re hearing.
Now, I want you to count how many times you see a circle flash on screen. Let’s do that one more time. Did you see it flash twice? Many people do, yet without the sound, it becomes clear that the circle is only flashing once. In this case, the sound has altered your perceived vision.
The next one works best with other people around. I’ll play two tones, and you tell me if they’re ascending or descending—in other words, are the notes played from low to high or high to low? Listen to this. Which was it? How about this one? Write down what you heard for each number and let us know in the comments. Chances are, if you compare with enough people, you’ll all have different answers. Surprising, right?
How is it possible that you’re hearing something different from others? It’s an auditory illusion called the Tritone Paradox. It’s created in such a way that the tones contain both a higher and lower frequency in them, but our brains have a preference for which to listen to. Diana Deutsch, the creator of this illusion, found that your geography and language from infancy all play a role in deciding this preference.
Finally, listen to this audio clip of a gradually climbing tune. Yet, if I play the exact same clip back to you, it will sound like it’s only continuing to climb higher and higher. I assure you, this is the exact same clip I just played. You can rewind that section of this video over and over and check for yourself. Try it; each time you start it over, the tune seems to be climbing even higher. It’s called the Shepard tone illusion, of which there are many variations. In it, multiple sine waves are played on top of one another, raising in pitch while one quickly drops down an octave as the others continue rising. But our brain doesn’t notice this drop, and so the clips sound like they’re rising forever.
These illusions may help to explain how something like music can have such a profound yet varying effect on our minds, which we discuss in our new ASAP Science episode, along with the question of whether or not music can save your life. There’s a link in the description to watch it.
So, do you still trust your ears? If you have a burning question you want answered, ask it in the comments or on Facebook and Twitter. If you want the inside scoop on upcoming episode ideas and behind-the-scenes content, check out our personal Instagram and Twitter handles, and subscribe for more weekly science videos.
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This version removes any informal language, filler words, and maintains a clear and concise structure.
Illusion – A false idea or belief, or something that seems to be something it is not, often tricking the brain. – The magician’s trick created an illusion that made it look like he was floating in the air.
Sound – Vibrations that travel through the air or another medium and can be heard when they reach a person’s or animal’s ear. – The sound of the violin was so soothing that it helped me relax after a long day.
Music – Vocal or instrumental sounds combined in such a way as to produce beauty of form, harmony, and expression of emotion. – Listening to music can improve your mood and help you concentrate better on your homework.
Brain – The organ inside the head that controls thought, memory, feelings, and activity. – Learning to play an instrument can help develop different parts of the brain.
Effect – A change that is a result or consequence of an action or other cause. – The calming effect of classical music can help reduce stress and anxiety.
Audio – Sound, especially when recorded, transmitted, or reproduced. – The audio quality of the concert was so clear that it felt like the band was playing right in front of us.
Hear – To perceive sound with the ear. – I could hear the gentle sound of the piano from the next room.
Tones – Sounds with a specific pitch and quality, often used in music to create harmony and melody. – The different tones of the guitar strings create a beautiful melody when played together.
Vision – The ability to see; the visual perception of the environment. – Sometimes, our vision can be tricked by optical illusions, making us see things that aren’t really there.
Frequency – The number of times a sound wave repeats in a second, determining the pitch of the sound. – High-frequency sounds, like a whistle, have a higher pitch than low-frequency sounds, like a drum.
