Category: Science

The United States Population makes up 4.2% of the total world population. That’s around 342 million people which when you look at it like that, seems like a lot. 

Let’s add another 0.2% to that. Approximately 16.6 million people. 

In total, this is above 350 million people. That’s 1 in 23 people.

Now, what do all these values mean?

1 in 23 people you meet, has some form of fully-fledged synesthesia, defined as the brain confusing multiple unrelated senses, causing you to experience more than one sense simultaneously.

How do people perceive senses?

Typically, the brain follows three steps. Detection, signaling, and processing. Detection is when the senses – hearing, sight, touch, taste, and smell – pick up your surroundings. Next, signaling. The organs related to these senses send signals to your brain, telling it what you are experiencing. Then, the brain processes these signals, allowing you to become aware of what is happening. 

Here’s an example. 

Your nose picks up the smell of something burning on the stove. Then, your nose sends signals to the brain. Finally, the brain processes the signals and lets you know that there is something burning. 

How does synesthesia work then?

People with synesthesia have different processing steps. Instead of the information being processed with a singular part of the brain, it goes through two or more areas of the brain at the same time, causing multiple effects. 

For example, chromesthesia. When people with chromesthesia hear a sound, they recognize it for whatever it may be, but in addition to processing the sound, they also see a color due to the sound, causing chromesthesia to also be known as sound-to-color synesthesia. 

Chromesthesia, like any other type of synesthesia, is not interpreted exactly the same for all people with the condition. Some experience the color as if they are actually seeing it, while others have a different perception known as the “internal screen” effect. The color is seen “internally” and in the head, rather than an actual sighting. 

How many kinds of synesthesia are there?

For each sense, the brain can identify many different things. Sight leads to color, pattern, texture, and shape; hearing leads to volume pitch and frequency; and touch leads to temperature, pressure, texture, vibration, and pain. Due to the many combinations between the senses, researchers estimate that there could be over 150 forms of synesthesia, however only 60 are formally identified. 

Some forms are chromesthesia, previously mentioned; auditory-tactile synesthesia, hearing sounds leads to feeling touch-based sensations; hearing-motion synesthesia, people hear sounds in relation to seeing moving objects; and day-color synesthesia, certain colors are associated with each day of the week.

Why does synesthesia occur?

While experts don’t fully understand why synesthesia happens, they have categorized it into three specific categories. 

Firstly, developmental synesthesia. Those with developmental synesthesia are “neurodivergent”, meaning that their brain developed and works in a way that is separate from people whose brains developed “neurotypically”. The factors that may lead to developmental synesthesia are brain development, brain structure, and genetics. 

There is existing evidence that suggests that early on in life, all people have synesthesia, meaning it must fade for all people, causing only a small percentage of people to have it. The small percentage of people who do have it, have more connections between their brain areas, which could explain why multiple brain areas activate due to one type of sensory input. In addition, it could explain why people with autism spectrum disorder have triple the rate of synesthesia in comparison to people without autism spectrum disorder. 

Genetics wise, synesthesia appears to run in families, however since there is variation from person to person, it implies that it is not learned, but rather genetically based.

Secondly, there is acquired synesthesia. Those who acquire synesthesia typically have this occur due to damage in the brain. Experts who have studied the topic believe that it is because the connections within the brain change and evolve as the brain recovers from injury.  

However, acquired synesthesia tends to be different from developmental synesthesia. Acquired synesthesia is typical;ly less consistent and more circumstantial than developmental synesthesia and can also also disappear with time. 

Finally, there is drug-induced synesthesia. Nonmedical usage of certain drugs in certain amounts can cause synesthesia. These drugs are known as psychedelics, including LSD, dimethyltryptamine, peyote, and psilocybin. 

Drug-induced synesthesia is emotion dependent and naturally, only occurs as a result of taking the drug, not organically. 

Does synesthesia require prevention or treatment?

Aside from drug-induced synesthesia, synesthesia is not preventable and doesn’t require treatment, however some forms of synesthesia can be managed or minimized if the effects are disliked. 

In the 1960s, Robert Ettinger first created the concept of cryonics in his book, The Prospect of Immortality. Now, you may be wondering: what exactly is cryonics?

Cryonics is the preservation of humans or animals at very low temperatures after legally announced death. Its goal is to eventually be able to revive the preserved beings and cure any possible disease they may have. However, currently, only preservation is possible, not revival.

So… how does it work then?

The science behind cryonics originates from the concepts of cryopreservation and cryobiology. In nature, this can be seen in animals like the northern wood frog, which survives freezing conditions by allowing 60 to 70 percent of its body water to freeze for multiple months, also known as cryoprotection. The lowered temperatures of the tree frog slow or stop metabolism, protecting it from ischemic injury – tissue damage caused by lowered or no blood flow.

However, this freezing is not possible without cryoprotectants(CPAS), such as glycerol and dimethyl sulfoxide(DMSO), which prevent ice crystal formation. The northern wood frog uses glycerol and glucose as the cryoprotectant in their blood, stored in the liver glycogen, and turned into glycerol and glucose once the freezing process initiates.

An important thing to note is that the cryoprotectants do not ensure no difficulties, as there are various methods to cryopreservation – programmable slow freezing, vitrification, and low-CPA vitrification – all of which end with the same general end result, yet the method of vitrification reduces or prevents the possibility of damaged ice crystals being formed. Vitrification turns the tissue into an almost “glass-like” state and allows cells or tissues to be frozen without freezing damage.

This leads us to today’s cryopreservation success. Cells, sperm, and embryos are all relatively common examples of successful freezing and revival that are used in modern medicine. In addition, tissues and organs can sometimes be preserved in a shorter-term time span, but still preserved nonetheless. One example is brain tissue, known to be highly complex and fragile, which can only be partially preserved, as only some neural markers remain intact.

These issues with freezing tissue and organs, which are what make up the human body, cause freezing a whole human to be problematic.

There are also many other problems beginning with cryodamage, where ice crystals damage cells and possibly structural stress, leading to cracks or ruptures. Next, there are brain preservation issues, which were partially mentioned before. As the brain is what runs the body, it is the most important organ to preserve, however anoxia (oxygen loss) and reperfusion injury (damage caused by the return of blood) are two main problems. It is also unknown if memories would survive the freezing and revival. The chemicals used in cryonics could also cause damage to the cells due to the high concentrations needed, along with the matter of the different cell types, which cause different issues. Cryonics uses one method of preservation for the entire body, which could prove to be a problem in the future when revival attempts are made.

Apart from scientific issues, there are also more typical matters, such as cost, which can range from $28,000 to $200,000 and would require lifelong planning; legal and ethical issues, since cryonics is not a legally recognized medicine; and simply the limited research revolving around the topic.

Despite the possible problems, there are claims of 300+ patients in a facility in the United States under the Alcor Life Extension Foundation, with over 1,200 people signed up for the procedure post-death as of 2014.

You may now be asking, “What exactly is this procedure?”

It begins after death, it is required that there be formal consent given prior. Time is extremely important in this procedure, as the process starts 1-2 minutes post-death. First, there is rapid cooling in an ice bath, then artificial circulation through CPR-like support. The required amounts of cryoprotectants are then injected, and cooling continues to occur. After this, the body will be stored in liquid nitrogen at a temperature of -196 degrees Celsius. It is important to note that this is only the preservation process, and the revival process has not been tested yet, as there is currently no technology that exists that would allow for this to occur. The cellular damage would have to be repaired, along with reversing the initial cause of death, and restoring any issues with brain function and memory.

While it is possible that cryonics may work, there is no current concrete proof. However, there is progress being made when it comes to research about hypothermia, which is used to protect the brain and can extend survival after cardiac arrest. There are also advances in organ preservation, such as the heart, lungs, and skin, which are important for transplants. It is important to note, though, that there is currently no explicit research on cryonics and the revival, as there are legal issues, along with pessimistic views on the actual feasibility of cryonics.

Authored by Diya Vipin Pillai and Katherine Yao