Synesthesia

Synesthesia is a phenomenon in which one sense perception (e.g., hearing, sight, taste, touch) activates or is associated with the perception of another sense, without an actual stimulus for that second sense. People with synesthesia may experience unusual and unfamiliar perceptions, such as seeing colors when listening to music, experiencing taste when touching objects, or associations between colors and numbers.

Examples of synesthesia include:

1. Graphematic synesthesia: People with this type of synesthesia may see letters and numbers as specific colors or shapes.
2. Color auditory synesthesia: They can see colors when they listen to music or hear sounds, and associate certain colors with certain sounds.
3. Taste synesthesia: People with this type of synesthesia may experience a certain taste when touching objects or seeing certain colors.

Synesthesia is a relatively rare phenomenon, and its mechanisms are not fully understood. It is not a mental disorder or pathology, and in most cases synesthesia does not pose health problems. In some cases, people with synesthesia can use their features in art or music to create unique visual or sound works.

Synesthesia can be an interesting research subject for scientists who seek to understand how the human brain works and how different senses and perceptions relate to each other. [1]

Synesthesia is a multitude of phenomena that can be studied in both psychology and neurobiology. This multifaceted phenomenon is studied from a psychological perspective to understand how different sense perceptions and sensations interact in people and what the psychological and cognitive consequences of synesthesia might be. For example, researchers are studying how synesthesia may affect the ability to engage in associative thinking, creativity, and art appreciation.

From the point of view of psychology, synesthesia can also be considered as a type of associative experience and perception when different sensory modalities are intertwined. Psychologists study how synesthetic associations are formed and maintained and how they affect human psychological processes.

Synesthesia is also interesting from a neurobiological and neuropsychological point of view, as it is related to the peculiarities of brain functioning. Research in this area allows us to understand which parts of the brain and neural networks may be responsible for synesthetic experiences.

Thus, synesthesia is an interesting multifaceted phenomenon that is being investigated in psychology, neurobiology, and other scientific disciplines to better understand the relationship between different types of sense perceptions and brain processes.

Causes of the synesthesias

The scientific explanation of synesthesia is related to the peculiarities of the functioning of neural connections and interaction of different brain regions. There is no unambiguous cause of synaesthesia, but there are several theories:

1. Genetic predisposition: Some research suggests that synesthesia may be inherited. This may explain the occurrence of synesthetic experiences in several family members.
2. Structural features of the brain: People with synaesthesia are thought to have unusual connections between different areas of the brain, allowing the different senses to interact. For example, colors may be associated with letters or numbers because the corresponding brain areas are activated simultaneously.
3. Brain plasticity: It is possible that certain events or experiences in early childhood may contribute to the formation of synesthetic connections in the brain.
4. Neurochemical factors: Changes in the levels of neurotransmitters such as glutamate may play a role in causing synesthesia. [2]

Pathogenesis

The mechanism of synesthesia, that is, the phenomenon in which some sensory perceptions cause associations with other sensory perceptions, is not fully understood. However, there are several hypotheses and theories that attempt to explain this phenomenon. Here are some of them:

1. Cross-activation of neural pathways hypothesis: According to this hypothesis, in people with synaesthesia, neurons normally responsible for processing one type of sensory information may be associated or crossed with neurons responsible for processing another type of sensory information. This can result in a stimulus from one sensory perception causing associations with other sensory perceptions.
2. Hypothesis of underdevelopment of neural mechanisms in children: According to this hypothesis, synaesthesia may occur due to underdevelopment of neural mechanisms in children, which may lead to temporal connectivity between different sensory areas of the brain.
3. Genetic predisposition hypothesis: It is thought that synaesthesia may be inherited and associated with certain genetic factors. Some studies suggest that synaesthesia may be more common among close relatives of synaesthetes.
4. Cortical cross-activation hypothesis: According to this hypothesis, synaesthesia may be due to cross-activation of different cortical areas of the brain that normally operate independently of each other. This may result in a stimulus from one sensory perception causing activation of other areas, which in turn causes synesthetic experiences.

The pathogenesis of synesthesia is not yet fully understood, and research in this area is ongoing. However, there are several theories and hypotheses about how synesthetic experiences may occur:

1. Genetic factors: It is thought that synaesthesia may be inherited in some cases. Research into the genetic nature of synaesthesia is ongoing.
2. Neurological mechanisms: Some studies suggest that synaesthesia may be associated with changes in brain structure and function. For example, some areas of the brain responsible for processing sensory information may be connected or crossed, leading to the perception of unusual sensory combinations.
3. Neurochemical Mechanisms: Research also suggests that synesthesia may be related to changes in the concentration of neurotransmitters (chemicals that transmit signals between neurons) in the brain.
4. Development in childhood: In some people, synesthesia may occur in childhood as a result of certain visual or sound experiences that affect the development of their sensory connections in the brain.
5. Structural features of the brain: Some studies have linked synesthesia to individual structural features of the brain, such as increased connectivity between different brain regions.
6. The immune hypothesis of synaesthesia. [3]

Synesthesia is related to the way different areas of the brain work and interact with each other. The main areas of the brain thought to be involved in synaesthesia include:

1. Cortex: Synesthetic associations, such as associations between colors and letters or musical notes, are often associated with the cerebral cortex. This area of the brain is involved in analyzing and processing sensory information.
2. Thalamus: The thalamus plays a role in the transmission of sensory information between different parts of the brain. Abnormalities in the thalamus can affect synesthetic experiences.
3. Synesthetic Cortical Bridge: This area of the cortex is considered important for synesthesia. It may be responsible for the interaction between different sensory modalities such as vision, hearing and touch.
4. Somatosensory cortex: This area of the brain is associated with processing sensory information, including skin sensations and bodily sensations. Some people with synaesthesia have synaesthetic associations between visible stimuli and skin sensations.

However, the exact mechanisms of synaesthesia remain the subject of active research, and it is a complex phenomenon that is not yet fully understood. Brain function and its influence on synaesthesia may differ from person to person, and additional research will help to reveal this phenomenon more fully. [4]

Symptoms of the synesthesias

Symptoms of synesthesia include experiences in which one sense causes an automatic reaction in another sense. The specific symptoms and types of synesthesia can vary from person to person. The following are the main symptoms characteristic of different forms of synesthesia:

1. Graphematic synesthesia: Letters, numbers, or words evoke color associations. For example, the letter "A" may always be associated with the color red and the letter "B" with the color blue.
2. Color Synesthesia: Sounds, music, noises, or voices evoke color associations. For example, a certain melody may be perceived as "green" or "purple."
3. Lexical synaesthesia: Words or sounds can evoke associations with tastes, smells, or textures. For example, the word "cat" may evoke the taste of "strawberry" or "sand."
4. Kinesthetic synesthesia: Movements, touches, or sensations can trigger sound associations, color perceptions, or other experiences. For example, when touching a certain texture, a person may hear a certain sound.
5. Spatial synesthesia: In this form of synesthesia, stimulation of a single sensation (e.g., numbers, letters, sounds) triggers the perception of spatial or geometric shapes in the synesthete's mind. For example, for some people, numbers may have specific locations in space, and they see them in a particular sequence.
6. Color Synesthesia: In this form of synesthesia, stimulation of a single sensation or sound causes the perception of certain colors. For example, when a synesthete hears a certain melody, he or she may see or associate it with a certain color.
7. Taste synesthesia: In this form of synesthesia, stimulation of one sensation (e.g., words, musical notes) causes the perception of a particular taste. For example, some synesthetes can taste letters or words.
8. Sensation of texture or shape: In some cases, synesthetes can sense the texture or shape of objects based on sound or visual stimuli. For example, musical sounds may evoke a sense of smoothness or roughness.
9. Odor Synesthesia: People with this type of synesthesia may perceive certain smells as colors, shapes, or textures. For example, the scent of blooming roses may be associated with the color red.
10. Tactile synesthesia: In this case, sensations on the skin can trigger perceptions of colors, sounds, or other sensory phenomena. For example, touching a smooth surface may be associated with the sound of a melody.
11. Spatio-temporal synesthesia: This type of synesthesia involves the perception of time and space in unusual forms. For example, months or numbers may be represented as patches of color in space.
12. Musical synesthesia: People with this type of synesthesia may perceive music through visual images, colors, or shapes. For example, certain notes or chords may be associated with certain colors.
13. Visual synesthesia: This type of synesthesia involves the cross-perception of visual impressions and other sensory perceptions. For example, words or sounds may trigger color associations.

Mirror-touch synesthesia is a form of synesthesia in which a person experiences the sensation of touch or physical contact when they see or perceive another person touching them. That is, if a person with this form of synesthesia sees someone touching their skin or an object, they may experience the touch themselves, even though they are not actually being touched.

For example, if a person with mirror synesthesia sees someone stroking a cat, they themselves can feel that smooth rough contact on their own skin, even though there is no actual physical contact.

The mirror touch of synesthesia can be quite intense and perceived as real physical sensations. This phenomenon is being researched in the fields of neuroscience and psychology, and its exact mechanisms are not fully understood. However, it provides a better understanding of how different areas of the brain can interact and influence each other. [5]

Interaction of sensation, sensitization and synaesthesia

These are all aspects of perceiving and experiencing the world related to the functioning of the nervous system. Let's look at each of these concepts:

1. Synesthesia: As I mentioned earlier, synesthesia is a neurological phenomenon in which one sense or perception is intertwined or merged with another. For example, synesthetes may associate numbers or letters with certain colors, sounds, or textures. This unusual intersection of the senses creates a unique experience of the world.
2. Sensitization: This term is commonly used in a medical context and refers to an increased sensitivity of an organ or organ system to stimuli or stimuli. For example, sensitization may manifest as increased sensitivity to pain, light, sound, or other external stimuli.
3. Interaction of sensations: Human perception of the world is a complex and multifaceted process in which different senses and nervous systems work together. The interaction of sensations can occur in a variety of situations. For example, the aroma of food can influence the perception of its taste, and also cause emotional reactions.

Synaesthesia, although a form of sensation interaction, is a more specific and unusual case in which the overlap of sensations is automatic and permanent for the synaesthete. While sensitization may be temporary or caused by specific conditions, synesthesia is part of a person's neurological trait.

Both of these phenomena are related to the functioning of the nervous system and can vary in intensity and severity from person to person.

Forms

Synesthesia can manifest itself in a variety of ways, including the following types:

1. Color Synesthesia: This is one of the most common forms of synesthesia. People with color synesthesia see certain colors when they hear sounds, music, letters, numbers, or words. For example, a particular note of music or a letter of the alphabet may cause them to associate it with a particular color.
2. Sound synesthesia: This type of synesthesia involves the fact that sounds trigger the perception of certain textures, shapes, or movements. For example, the sound of music can be perceived as a visual representation of shapes and lines.
3. Tastesynesthesia: Taste synesthesia refers to the experience of taste when perceiving certain sounds, odors, or textures. For example, the sound of a musical instrument may trigger the flavor perception of a certain food.
4. Touch sensation and tactile synesthesia: This type of synesthesia involves certain stimuli causing a sense of touch or tactile sensation on the skin. For example, the sound of music may cause a "tickling" or "squinting" sensation on the skin.
5. Odor-synesthesia(odor synesthesia): People with this type of synesthesia can experience scents as colors, shapes, or sounds. For example, a particular odor may cause them to have visual images.
6. Tactile synesthesia: This type of synesthesia is related to sensations of touch or touching, which can trigger other senses such as colors or tastes.
7. Spatio-temporal synesthesia: People with this synesthesia may perceive space and time in the form of shapes, colors, or sounds. For example, they may see years as colored ribbons or musical notes may have a specific spatial arrangement.
8. Musical synesthesia: This type of synesthesia is related to music. People with musical synesthesia may perceive sounds as colors, shapes, or textures. For example, a certain melody may cause them to perceive colors visually.
9. Visual synesthesia: This type of synesthesia manifests itself as associations between different visual perceptions and other senses. For example, numbers or letters may evoke certain colors or shapes in a person.

Diagnostics of the synesthesias

A synaesthesia test often includes a set of questions or tasks that aim to detect the presence of synesthetic experiences in a person. However, it is worth noting that synesthesia is an internal experience, and there is no single standardized test that will unequivocally determine the presence of this phenomenon. Synesthesia is usually diagnosed on the basis of descriptions and experiences told by the person himself.

Here are some questions and tasks that can help identify synesthesia experiences:

1. What colors do you associate with certain letters, numbers, or words?
2. Can you describe what sounds or musical notes trigger your perception of colors?
3. Do you have associations between certain tastes and smells and words, sounds, or colors?
4. Can movements or sensations cause you to associate sounds, colors, or tastes?
5. Describe any unusual experiences or associations you have when you perceive the world around you.

It is important to remember that synaesthesia can manifest to varying degrees and in different people, and the answers to these questions may vary. [6]

If you want to determine if you have signs of synesthesia, you can try the following online tests:

1. Color Synesthesia Test: This test allows you to determine if you associate colors with numbers, letters, or sounds. For example, you may be shown letters or numbers and asked what color they are to you.
2. Taste Synesthesia Test: This test can help you determine if you associate certain sounds or words with certain tastes. You may be presented with sounds or words and asked what flavor they evoke.
3. Spatial Synesthesia Test: This test allows you to determine if you associate numbers or sounds with specific locations in space. For example, you may be presented with numbers or sounds and asked where they are located in front of you.

These tests can be fun, but they are not diagnostic tools and are not a substitute for consulting a professional if you suspect synesthesia or it is affecting your life.

Treatment of the synesthesias

Synesthesia generally does not require treatment, as it is not a medical or psychological disorder. Rather, it is a unique and non-harmful phenomenon in which some people's senses and perceptions become intertwined.

However, if synesthesia is causing discomfort or significant discomfort, the individual may see a psychologist or psychiatrist for counseling and support. In some cases where synaesthesia interferes with normal functioning, strategies may be offered to manage or reduce the intensity of the synaesthetic experience.

It is important to note that synesthesia can also be a source of creative inspiration for artists, musicians, and writers, and some people with synesthesia use their experiences to create unique works of art.

If you or someone you love has synesthesia and it's causing concern, the best solution is to see a specialist for a more detailed evaluation and recommendations.

Famous people with synesthesia

Synesthesia is a rare and individual phenomenon, and it can manifest itself to varying degrees in different people. Some famous personalities and artists have reported their synesthetic experiences. Here are some examples of famous people with synesthesia:

1. Vladimir Nabokov: The famous Russian-American writer and author of "Lolita" was a synesthete who saw letters and numbers in certain colors.
2. Fyodor Dostoevsky: The great Russian writer Fyodor Dostoevsky was also a synesthete and described his experiences with associations between words and colors.
3. Oliver Sacks: The renowned neuroscientist and writer, author of The Man Who Mistook His Wife for a Hat, had various types of synesthesia and researched the phenomenon extensively.
4. Kandinsky: Russian artist Wassily Kandinsky created his abstract works based on his associations between colors and sounds.
5. Billy Joel: Musician and singer Billy Joel also has synesthetic experiences and sees colors in connection with music.
6. Richard Feinman: Physicist and Nobel Prize winner Richard Feinman had numerical synesthesia, in which numbers caused him to make color associations.

These are just a few examples of famous people with synesthesia.

A list of some of the books and studies related to the study of synesthesia

1. "Wednesday Is Indigo Blue: Discovering the Brain of Synesthesia" (2011) by Richard E. Cytowic and David M. Eagleman.
2. "The Man Who Tasted Shapes" (1993) by Richard E. Cytowic.
3. "Synesthesia: A Union of the Senses" (1997) by Richard E. Cytowic.
4. "The Hidden Sense: Synesthesia in Art and Science" (2007) by Cretien van Campen.
5. "Synesthesia: Perspectives from Cognitive Neuroscience" (2004) edited by Lynn C. Robertson and Noam Sagiv.
6. "The Synesthetic Experience: A Study of Synesthesia in Literature and Music" (2013) by K. R. Britt.
7. "The Mind of a Mnemonist: A Little Book About a Vast Memory" (1968) by A. R. Luria (This classic work discusses the case of S., a mnemonist with synesthetic experiences).
8. "Synesthetic Design: Handbook for a Multi-Sensory Approach" (2017) by Michelle M. Wenderlich and Bernd Hitzeroth.
9. "The Oxford Handbook of Synesthesia" (2013) edited by Julia Simner and Edward M. Hubbard.
10. "Synesthesia and the Arts" (2017) edited by Stephen E. Palmer and Berit Brogaard.