You have undoubtedly heard or experienced visual trickery at some point, but what about your ears? While the average person is very familiar with the concept of optical illusions, many people are not aware of the fact that auditory illusions exist as well. This is likely because visual tricks are much easier to verify than audio ones. For instance, if you wander into the woods and think you see Big Foot, you can easily take a picture or chase him down for a conversation (not recommended), to verify whether he actually exists.
However, on the other hand, if you think you hear something off in the distance, there may not be a way to verify whether you have sensitive ears or if you are a victim of audio trickery. Nevertheless, both your ears and eyes can be deceived. With that in mind, the following is a closer look at how the human eye and ears can be tricked as well as a comparison of which of these two senses are most likely to be hoodwinked.
Your Eyes are Playing Tricks on You
Although many people regularly use phrases such as, “I’ll believe it when I see it,” or “seeing is believing” these expressions are misleading at best. In fact, the eyes are one of the least reliable parts of the body. This is because they are connected to a highly complex visual system that perceives and interprets images before sending them to your eyes. In other words, these illusions occur because your eyes do not function on their own. Rather, they rely heavily on the brain to be able to visually perceive the people and objects that appear before you.
As Michael Bach, who is a well-known vision scientist and professor of neurobiophysics, once stated, “a mismatch between the immediate visual impression and the actual properties of the object.” This means that people are prone to seeing visual illusions because the perception of the objects in front of us is not necessarily an accurate depiction of these objects. Since every single thing in one’s view must be interpreted through the brain, this always leaves some wiggle room in terms of interpretation.
Floaters, Stars, and More
One of the many culprits behind many visual illusions is eye floaters. For those unfamiliar, floaters are small shadows, specks, or spots that seem to float in and out of one’s field of vision. These floaters are small irregularities that are present in the fluid of the eye. Therefore, while they may seem like illusions or figments of your imagination, floaters are actually real things that can cause our vision to be unreliable. Moreover, floaters become increasingly common with age. Nevertheless, this is just one reason why human eyes are not reliable.
In addition to floaters, there are quite a few medical causes of eye trickery. For instance, epilepsy and high fevers can cause people to see spots of flashing shapes. Also, those who suffer from migraines or are prone to seizures can see visual auras. These are visual perceptual disturbances that originate in the occipital cortex or the retina. Also, Parkinson’s and thyroid disease can cause visual hallucinations.
Fun Eye Illusions
On the other hand, there are also plenty of visual illusions that we witness in our everyday lives. For instance, peripheral drift illusion. This is a term that describes the anomalous motion illusion that is often observed via peripheral vision. This is because illusionary motion often appears when figures include a black region and an adjacent dark gray region or a white region and an adjacent light gray region. This illusion is more enhanced when the image has curved edges and one common center-point for all regions.
In keeping with that, “rotating snakes” is one popular internet illusion that many people gravitate towards. According to the creator, the way this works is by going from black to dark gray to white to light gray. Once again, the illusion is magnified by making it circular with a common center point.
Eye Illusion Summary: If we think of vision as a type of language, no matter how great your vision or brain capacity may be, the fact that the brain serves as an interpreter for the surrounding environment always leaves room for interpretation. This means that visual processing can be tricked in a way that is beyond human control.
Are Your Ears Deceiving You?
On another note, you may have been misguided into believing that your ears are the home of the most reliable of the five senses. However, this couldn’t be further from the truth. Just as with the eyes, the ears can and do play tricks on us as well. For instance, an auditory adaptation is a phenomenon that involves the gradual loss of important aspects of your hearing.
While this phenomenon can be a chronic one, the average person experiences this phenomenon in various ways. For instance, if you go to an area that has vastly different noises and sounds than what you are used to, you may become distracted by noises that are not necessarily loud or annoying. Rather, they are simply different from the noises you are used to.
Another example of auditory adaptation is when you work or live in a noisy area. When you first start experiencing the noise, you will likely become annoyed or frustrated by the noise. However, over time, you will become so used to the noise that you hardly even notice it. Also, as mentioned, auditory adaptation can occur as you age.
While it is a well-known fact that many people tend to lose their hearing as they age, many people don’t realize that those who lose their hearing don’t necessarily realize that they are losing their hearing. Rather, what happens is people lose their hearing over time, and their brains trick them into thinking that their hearing is still normal. These are the situations in which there is a stubborn parent or grandparent who refuses to wear a hearing aid because they “hear just fine”.
Another reason for auditory illusions is that, as humans, our sense of hearing is limited. We are only capable of hearing sounds clearly when they are around 20Hz to 20,000Hz. Sounds that go outside of this parameter often cause strange things to happen to our hearing. In other words, auditory illusions are essentially a result of our hearing system struggling to make sense of things it is not wired to comprehend.
Auditory Illusions and the McGurk Effect
In addition to auditory adaptations, auditory illusions are also a common way your ears can deceive you. For those who are yet unfamiliar, “auditory illusion” is a term that refers to the phenomenon of hearing things that are either not actually there or hearing things in a manner that is different from what they actually are.
One example of this is the McGurk Effect. Named after the British psychologist Harry McGurk, who helped discover this phenomenon, the McGurk Effect is a term that is used to describe what happens when your eyes interfere with your hearing. In other words, the way in which a person’s mouth is shaped when they are speaking can alter how our brain and ears perceive these words. In short, rather than simply absorbing sounds, the brain also plays a role by interpreting what is being seen and heard, and incorporates all of these elements into the body’s “sound system”.
The Shepherd Illusion
Another example of an auditory solution is the Shepherd Illusion. Named after the California-based neuro-scientist Roger Shepard, the Shepherd Illusion describes how a complex mixture of sine waves (a term for the well-known visual illustration of sound waves often used in geometry), can cause auditory illusions in music. This term is used to describe what happens when you may listen to music and the basic scale includes a rising pitch. When this scale is played repeatedly, it will start to sound like the pitch is continually and progressively rising, when in reality, the pitch is remaining the same. This is an auditory illusion that is often used in electronic pop music, among other things.
The Tritone Paradox
Simply put, the Tritone Paradox is a variation of the Shepherd Illusion. In this instance, a pair of notes are played directly after one another with a small space in between them, which is known as a “tritone.” The notes referred to here are a pair of Shepherd Tones. This means the notes will either sound like they are ascending or descending, but that’s not the tricky part.
The illusion comes into play because, when they are listened to as a group, those listening will have different perceptions of which notes are high and which ones are low. Even more interesting, according to the creator of the theory, the British musicologist Diana Deutsch, the culture or language you speak plays a major role in how these notes are perceived.
Ear Illusion Summary: Much like our vision, our hearing is subjected to auditory illusions that occur due to things that are outside of our control. In particular, there is a whole system involved in our hearing which requires our brains to help perceive the sounds we are hearing.
Which System is More Complex?
Ironically, although the general consensus is that sight comes before hearing, it is actually our last sense to develop. This is because our vision is the least useful sense while in utero. As humans, we are all taught that vision is our most important and most complex system. However, that is not necessarily the case. Sure, on the one hand, most of us believe that losing our vision would be one of the worst fates ever. Nevertheless, given that plenty of people are born blind and manage their lives just fine, the notion that vision is the most important sense may be a tad exaggerated. In fact, society has evolved to a point in which there is a wide variety of technology and devices that help those who lose their vision to live comfortable and productive lives.
Moreover, although maintaining one’s vision is obviously preferable, each of these systems plays a major role in how we interact with the world. For instance, while it may seem easier to avoid an object that is flying your way by seeing it, hearing the object is also a powerful part of this defense system. In fact, there may be times that you were able to dodge an object because you heard it coming before you saw it.
Either way, both hearing and vision are complex systems that the body depends on for survival. Each of them is also controlled by the cortical regions of the central nervous system (CNS). They are also two of the most delicate senses that tend to deteriorate more rapidly than the other senses. Each of them plays a major role in temporal and spatial organization. Both vision and are incapable of perceiving nothingness. On the one hand, if blackness surrounds you, your eyes will perceive gray rather than black. On the other hand, if you are in an area with zero sound, your ears will still perceive a slight sound to avoid the sound of complete silence.
Therefore, while we as a society have been led to believe that seeing is the most important sense ever, recent studies and research shows us that these two senses are more similar than we know and that they often work hand in hand.
The Bottom Line
While the brain’s auditory circuit takes up less space than the visual system, each of these systems is important to the body. These two senses work together to help keep the body as healthy and safe as possible. Either way, we technically see 20 to 100 times faster than we hear. An illustrated example of this is the fact that we see lightning (emissions of electromagnetic energy) sooner than we hear the thunder (sound waves). For this reason, we consider vision to be the most important sense. Nevertheless, as mentioned, there are plenty of people who survive and live happy, well-adjusted lives without vision.
Taking a cue from the animal kingdom, animals such as bats, sea urchins, olms, and many others, rely majorly on sight, and cannot see at all. If we are to believe the age-old adage that “nature doesn’t make mistakes,” it should be clear that the importance of hearing and vision are totally subjective. And to bring it back to trickery, each of these senses essentially needs the other in order to be optimally functional. Does that make sense?