Rubber Hand Illusion

 Blog post 1 

Rubber hand illusion 

One topic of perception that is completely compelling is the rubber hand illusion. The rubber hand illusion is when a person sits down at a table with both arms on it and forearms facing down. They then place a divider so you can no longer see one of your arms. Instead, they place a rubber arm with a hand in the position your arm could be. Synchronously they then stroke your index finger that you cannot see and the rubber one. After two and a half minutes of this people begin to experience that the rubber hand is their own.  

I found this topic to be very intriguing and hard to believe honestly. It is hard to imagine people being tricked into believing a rubber hand is their own but seem to work every single time. This shows the power perception truly has over us even when we are not conscious of it. I also find it interesting how the senses work together in scenarios like this. Meaning that this is multisensory. Not only are they using touch, but they are also using sight as well. Topics like this and the out-of-body experience make it seems as if they are magic tricks, but really it is us that are tricking ourselves.  

 

 

While doing more research on the topic I found a video of this being performed to multiple people and their reactions were very entertaining:  

https://www.youtube.com/watch?v=iPFSgLDCvAs 

 

Reference 

Rosenblum, L. D. (2011). See what I'm saying: the extraordinary powers of our five senses. W.W. Norton. 

Post #2 Echolocation - Angelina Marte

Echolocation     

    Along with my first post, another post I find intriguing is echolocation. As a child growing up,  you learn that the only few animals to use echolocation were bats and dolphins. Below is a link leading to an article on animal echolocation. As an adult learning that most if not all humans can learn how to echolocate is astonishing. Echolocation is typically used by people with vision impairments, to help them to "see". They produce clicks that bounce off of objects in their space, to be able to tell where those objects are exactly. 

Link To Bat Echolocation

    Not only this, but there are different techniques and uses for echolocation. Things such as "facial vision theory", hearing silent objects, and hearing space itself. Discovering echolocation in humans have allowed us to adapt to other normalcy's for people with vision issues. Another great example is beeping pitches where it's basically baseball, but with sound instead of vision. Below is a TED Talk on how kids who are blind use tongue clicks to navigate.

Post One - Prosopagnosia

 Prosopagnosia is known as the inability to recognize facial identities. This disorder prevents individuals from recognizing friends and family as well as themselves. It is only found in about two percent of the general population. Being that these individuals are incapable of facial recognition, most prosopagnosics actually use different features of an individual to correctly identify them. These features include hair color, style of clothing, voice, etc. Using these different identifiers make it easier for prosopagnosics to follow conversations, television shows and movies. 

A common misconception about this disorder is that many prosopagnosics have poor eyesight. However, prosopagnosia actually is caused by irregularities in the neural networks and is more common than we believe it to be. Hollywood star Brad Pitt has opened up about his struggle with facial recognition and how it has impacted his social life. He mentions how many people are offended that he doesn't recognize them but the truth is that he can't do anything to change it. Because of this, he actually prefers to stay in instead of go out so that he will not be put into uncomfortable situations. I would love to see further research into prosopagnosia and if the fusiform gyrus can be altered on either side to help those who suffer from the disorder to eventually be cured from it. 

https://www.faceblind.org/research/

https://www.medicaldaily.com/brad-pitt-says-he-has-face-blindness-prosopagnosia-more-common-thought-246184

https://www.brainandlife.org/articles/a-quirk-of-the-brain-called-prosopagnosia-makes-it-hard/ 

Post #1 Sommelier - Angelina Marte

     

Sommeliers

    One of the topics I was most interested in learning was the sommeliers. I was amazed on how advanced a wine specialists' brain can be just by learning and experience. I was also surprised on how little it had to do with their taste buds, showing how far the human brain could really go. Some things that I would like to learn more about his how their brains activate in those specific regions (left hemisphere) after they've taken a sip. A question that I have is how the brain reacts then to just looking at or even just smelling wine. Do the same areas activate like they do when the wine is tasted, if so, is it less activated or just as activated? 

    Something else that I was interested that was easier to figure out (but not as related to psychology) was how much sommeliers make. Their are such few of them in the world and what they do is so rare that I wanted to see if the income was worth their years of hard work. In my research, I found that the different levels of sommeliers make different amounts. The lowest level of sommeliers make between forty to fifty thousand a year. A certified/level two sommelier will make between sixty to seventy thousand a year. And a level three sommelier will have a salary of seventy to eighty thousand. Personally, this wouldn't suit my interests, but obviously it does for some, and goes well for them as well. 

Link To Sommelier Income

Post #3: Sense of Smell

 In chapter 3, the book discusses how your sense of smell can play a role in retrieving memories. Research done by Rachel Herz at Brown University has shown that scents help to render memories as more emotional. It has also shown that familiar smells illicit more brain activity in emotional brain centers than nonfamiliar smells. I found this to be interesting because I am able to associate different scents with certain memories. It is sometimes hard to remember specific details about memories, but scents have a way of bringing back the emotions associated with them. This video explains how smells can trigger memories. 

How Smells Trigger Memories - YouTube

Post #2: Daniel Kish

I found the story about Daniel Kish beginning of the book to be very engaging. It details how Kish was diagnosed with retinoblastoma in both eyes as an infant and had both eyes removed, but that never stopped him from gaining independence. Kish learned to use echolocation to navigate the world around him. Daniel's skills became so impressive that he is able to lead other blind individuals through mountain bike tours. His parents encouraged him from a young age to navigate and explore the world on his own. Kish attributes his navigation skills and expertise with echolocation to his parents' approach. Attached below is a video of Kish using echolocation while riding his bicycle.

Shorts: Daniel Kish's echolocation in action - YouTube

Post #1: Sommelier

A sommelier is a wine expert who is hired by a variety of establishments to test different wines to be served to their customers. In the book, The Extraordinary Powers of our Five Senses See What I'm Saying, author Laurence Rosenblum describes how difficult it is to become a master sommelier. Master sommeliers go through an exam that is sectioned off into three phases including: tasting, wine theory, and serving decorum. Due to the rigor of their exam there are only 167 masters in the world. I found it to be very interesting that brain scans have shown that as a sommelier sips, their brain shows enhanced activity in regions where someone would taste and smell as compared to a novice.

This video provides an overview of a sommelier course in New York City.

Intensive Sommelier Training Exclusively Available at ICE - YouTube

The Sound of Bass: How Do Deaf People Experience a Party?

The video from above interviews a few partiers who are deaf and begs the question, how do you enjoy music? They have really thoughtful answers and deep experiences even without being about to hear the music the same way hearing people can. They explain how music with a heavy bass is the best because its vibrations help them feel what others are experiencing. Proxy touch traveling to one's feet gives a sensational feel to an otherwise auditory stimuli. Dr. Dean Shibata, assistant professor of radiology at the University of Washington, says it best: "[Studies] suggest that the experience deaf people have when ‘feeling’ music is similar to the experience other people have when hearing music. The perception of the musical vibrations by the deaf is likely every bit as real as the equivalent sounds, since they are ultimately processed in the same part of the brain" (Neary 2001).

Neary, W. (2001, November 27). Brains of deaf people rewire to 'hear' music. University of Washington News. https://www.washington.edu/news/2001/11/27/brains-of-deaf-people-rewire-to-hear-music/. 

Hallucinations

Hallucinations are defined as the perception of a nonexistent object or event and the word originates from latin, meaning "to wander mentally" (Purse, 2020). Hallucinations could be involving hearing, seeing, feeling, smelling, or even tasting things that are not real. Disorders such as bipolar disorder and schizophrenia can cause hallucinations. Drug and alcohol use can also be a reason why an individual may experience hallucinations. There are even some less obvious causes to hallucinations such as migraines, middle/inner ear diseases, stroke, epilepsy, PTSD, and sleep deprivation. It is important for individuals experiencing this to seek for medical attention and remain calm (Purse, 2020). I believe this perception disorder is very interesting. 

References

Purse, M. (2020, July 21). What is a hallucination? Verywell Mind. https://www.verywellmind.com/what-are-hallucinations-378819

Top Sommelier Tries $15 Wines

 A sommelier is a wine steward or a professionally trained wine taster usually employed by a fine dining establishment. There are intense requirements to pass exams to become a sommelier. Steven Poe remembers the pressure of describing and recognizing 6 wines in only 25 minutes. They would have to recognize the grape variety, region of origin, and year. There are three major components to the exam itself. The final exam is invitation only and has a 97% failure rate. According to Rosembaum, recent brain scans reveal that sommeliers do not possess a superior sense of taste or smell but a neurological superpower. As they taste wine, their brains express a more vivid representation of flavor as parts of their brains responsible for taste and smell are enhanced. This activity is centered on the left-hemisphere of the brain which is responsible for analytical processing. These sommeliers’ brain scans were compared to novice wine-tasters.

I found this information so profoundly interesting. The fact that their are only 167 sommeliers worldwide is inconceivable. This number is based on Rosenblum's book See What I'm Saying which was published in 2010. According to The Court of Master Sommeliers, "There are 172 professionals who have earned the title of Master Sommelier as part of the Americas chapter since the organization’s inception. Of those, 144 are men and 28 are women. There are 269 professionals worldwide who have received the title of Master Sommelier since the first Master Sommelier Diploma Exam." (https://www.mastersommeliers.org/about)

I also found this video of one of America's best sommeliers trying $15 wines...it is pretty awesome - enjoy.

Depth Perception

Depth perception is used almost every days in the lives of many people. For example, depth perception is used when you are driving. Depth perception refers to your eyes ability to judge the distance between two objects (Larson, n.d). There are many different issues that can affect depth perception including amblyopia, strabismus,  trauma to one of your eyes, and blurry vision. Depth perception issues can affect everyday life in many ways such as impaired driving, squinting e.g. learning for kids, crossing the street, sports, pouring water, and even taking the stairs (Larson, n.d). In some cases, this can be treated but not always. I find this to be a very interesting perspective of how vision plays a role in everyday life.

References

Larson, J. (n.d.). Depth perception: What it is and how to treat issues. Healthline. https://www.healthline.com/health/eye-health/depth-perception 

Echolocation

 

The most interesting topic learned in this class was echolocation which is locating objects by reflecting sound. while reading the perception book I learned that blind people use echolocation to know where they are going. In specific, blind mountain bikers were able to know the trail they were rideing just based on echolocation. I further researched this topic and found that researchers did a study on blind and sighted people that never used echolocation before. While under a functional magnetic resonance imaging scanner, researchers played sounds in different parts of the room and found that when playing the sounds showed activity in non-sighted people's primary visual cortex which is similar to sighted people looking at visual stimuli (Servick, 2019)

References

Servick, K. (2019, October 1). Echolocation in blind people reveals the brain’s adaptive powers. Science | AAAS. https://www.sciencemag.org/news/2019/10/echolocation-blind-people-reveals-brain-s-adaptive-powers

Synesthesia

As described in the book, synesthesia is "is a systematic and involuntary sensory experience induced by an unrelated stimulus". It was captivating to read that letters induce color and other various sensations. I personally haven't met anyone who has synesthesia but I'm curious as to how it plays a role in their life. As a college student for example, they would typically write numerous papers in just one semester and I'm curious to see if their final drafts would appear colorful or if it would induce a specific taste based on the topic and word choice. 

While exploring the internet for more personable experiences, I found a great TED-Ed video titled "What Color is Tuesday? Exploring Synesthesia". My personal favorite line from the video was that synesthesia is considered to be a trait opposed to a disorder since nothing is wrong. The TED-Ed video breaks down the various "subcategories" of synesthesia and explains how it alters perception. The link is provided below: 

What Color is Tuesday?

Symmetry

       In the context of "See What I'm Saying", symmetry is the matched equalness of both sides of the body in humans and animals. High symmetry is the greater equalness of matched proportions such as face, arms, and legs; whereas Low symmetry would show the opposite, being a mis-proportioned body whereas one arm or leg is smaller in size. This also suggests poor genetic health amongst a low symmetry subject compared to a High symmetry subject which would be more healthier genetically. A person with a smaller wrist on one side of the body would be considered a Low on genetics, and a Low attractiveness also through smell. In contrast a High symmetry subject would be considered high on the genetic scale and more attractive through smell.

      This blew me away as also related right down to smell and genetics I am unsure If I'm following the concept of our book, I'm still trying to figure this one out! I don't know If I read this correctly but I read the book and re-read this a couple of times, so now I'm reaching out to the class for input. Please any comments or guidance would be most appreciated on this as my understandings aren't following my instincts and comprehension such far. Thanks! Attached is a good BBC documentary on this theory relating to smell.

https://www.bbc.com/news/science-environment-21150046

 

Auditory Approach System

      Another interesting topic from our book "See what I'm Saying" is the concept of the Auditory Approach System. Basically the Auditory Approach System is a warning, and protective mechanism against oncoming danger from other sources such as a speeding car that could be heading directly to a person and to which could cause bodily harm or death.

    

     After reading the chapter on this I decided to do some experiment's such as close my eyes and listen the sounds around me that I always in the past with look at for reference. One example was standing in the parking lot at work which has a lot of daily familiar sounds like trucks pulling in to front gate. I was surprised that I could map out where the trucks were and actually pinpoint their locations coming in and going to the loading dock approximately 100 yards in and to the left, I could even hear them swinging around and backing up to the loading dock. And also when I repeated this with my eyes open the were further away, out of danger than I thought. The book had mentioned this, that we tend to over-estimate on oncoming sound before it could become a danger to us. Attached is a link which delves into a lot of the survival responses that we deal with every day, I hope that you enjoy it.

https://lemonlimeadventures.com/auditory-system-sensory-processing-explained/

Proxy Touch

      I can give an example of playing the guitar in my experience, I started playing guitar at 13 years old. I am now 58 and am very familiar with the design and concept of a guitar fretboard, being the range and notes starting at fret number one going to fret number 22. With this design you have six strings over the fretboard being from heavier to lite as E,A,D,G,B,E. at fret one to twelve is one octave, from fret 13 to 22 is another octave being higher. The relevance here is that I have many choices with using proxy touch such as darning finger picks or a slide tube or both with right- and left-hand relationship or singular. This intermingles with devices that I can use or not and combine, touch, proxy touch, visual reference, and sound reference. In addition, I can play notes, cords, and lead riffs by feeling along the fretboard without necessarily visually looking down for reference but just by touch in relation to what part of the neck I’m at.

        Until now I never realized what was really going on with this concept and how It is defined until reading about this incredible relationship that our brain has with all of our senses. upon looking up additional information about Proxy Touch I came across this video of Sparse Haptic Proxy which interwinds touch feedback in Virtual environments, let me know what you think about this really cool video!

https://www.microsoft.com/en-us/research/publication/sparse-haptic-proxy-touch-feedback-in-virtual-environments-using-a-general-passive-prop/

Memory in perception

     Episodic memory is the memory for specific experiences from the past, these memories are stored in the hippocampus and surrounding area of our brains (Goldstein,2019). We use episodic memory, every time we identify stimuluses in our environment with Top-down processing. Top-down processing can be very misleading, due to the fact, that our expectations of a future event, being similar to one in our past, can lead to disappointment and in the extreme cases injury.

    Nondeclarative memories have the ability to alter our perception, though we are unaware of these unconscious memories, they still color our decisions and actions, while interacting with our environment. It is these memories, the echoes of "what we've seen, we see and what we've heard, we hear", that plays a giant role in the expectations that we place on others.

    

    

Environmental influence

     This semester studying Perception along side of Cognitive Psycology, has given me a much broader understanding of higher functions in the human brain and why I perceive situations the way that I do. The concept that perception is based on our environment and the information that we take from it and is colored by all of our experiences, has given me a greater look into why we all react to the world in the ways that we do. 

    To ensure survival and navigation trough our world, we use a combination of bottom-up processing and top-down processing, to encode information from our environment. many of our disappointments are based on constructive perception theories of expectations. Expecting people to behave the way that I think they should, has lead to many let downs in my life. The episodic memories of past experience have also kept me from taking chances and trying something new.

    From the Goldstein text I learned about the "Gestault Laws", which are innate principle of organization that we apply to our world to enable us to understand our environment. By using Top-down processing to decipher our world, we can actually change the structure of our brains, therefore altering our perception of the world around us. This gives me hope for a brighter future through changing my perception.

pandemic problems

    During the pandemic when the population was required to wear masks, I noticed that I was saying "huh" and "excuse me" a lot more. I began to wonder if I was having difficulty with my hearing, or lack of, so to speak. This semester my courses were a pairing of Perception and Cognitive Psycology, and it was then, that I learned that most of our sensory experiences are muliti-dimensional and involve different qualities (Goldstein,43,2019). I was having a multisensory issue.

    My courses taught me that, if a discussion is complicated, you're lip-reading. most lip-reading is an implicit skill, making it an automatic function. I never realized that I lived most of my life the "McGurk effect" way, meaning that what I saw was over-ridding what I heard. When posed with a problem of not being able to supplement my hearing with lip-reading, I was struggling to comprehend the words that were coming out of peoples mouths, which is a major problem for someone in the service industry.

    The knowledge that I could over come this issue, without the help of a doctor was a relief. Knowing that cross-sensory brain plasticity would save the day by rewiring my hard drive was gift of my education process.

    

 Moon Walking Bear

If you haven't already watched this video please do, before reading the rest of this post. 

TFL Viral - Awareness Test (Moonwalking Bear) - Bing video

Well... Did you see the moon walking bear? This test is an awareness test that helps you realize your level of awareness. If you missed the moon walking bear, you experienced something called selective perception. Selective perception is when a person only really sees what they are looking for and not anything else. This is why when crimes occur, sometimes a persons description of the event can be not so reliable.

Speech Perception

Lip reading is something we do every day whether we realize it or not. Using facial expressions, watching speech movements, and simply watching the talkers face all allow us to enhance the speech we hear. Working in a health office and previously in retail allowed me to relate this to the current COVID pandemic. I distinctly remember people say "sorry I can't hear you, I'm wearing a mask", and at the time, I'd just chuckled and repeated what I said. But after going in deeper to what actually goes into speech perception, I realized that having the majority of our face covered really affects speech communication.

I found an article in The Journal of the Acoustical Society of America which compares different types of face masks (N95, surgical, cloth etc.) and their effect speech perception. This study focused in on acoustic output and speech perception The link is down below: 

Effects of face masks on acoustic analysis and speech perception: Implications for peri-pandemic protocols

The McGurk Effect

 The McGurk Effect is an illusion that illustrates how discrepancies in perceived stimuli can trick and confuse our brains, also showing a certain hierarchy when it comes to the "power" that each sense holds in relation to the other ones. As it turns out - they are not equal, and a human brain basically has its own "trustworthiness score".
Throughout the book a certain theme emerges: whether it comes to external input interpretation, internal cognition or memory use, our brains like things that make sense in the presented context (think: chess masters being able to remember the location of pieces from a real game, but not a random one, and sommeliers being able to remember pairings that actually go together way better than random ones), and the McGurk effect is no different.

In this illusion, a participant hears one syllable, but sees a different one (through lip reading). As it turns out, the visual input almost always seems to override the auditory one! If we see someone say the syllable va, we will hear that syllable, even though in reality a different one is uttered (ba for example). This shows that in a critical situation where the brain has to make sense from conflicting inputs, it will trust the vision more than the hearing for example, rather than creating some sort of an equal blend.

What is even more interesting, the effect seems to be universal and durable. As reported in our textbook, it worked in every tested language and still tricks researchers that spent a lion share of their careers trying to understand it. It is very interesting that a relatively simple at a first sight trick carries such an astounding amount of informative value. It also helps to put in perspective how little we really know so far, and how much else there is still to discover in the worlds of perception and neuroscience at large as well, with new studies on the subject like https://www.nature.com/articles/s41598-018-30798-8 looking at the phenomenon from different angles.

Verbal Overshadowing

 Verbal Overshadowing is an interesting perceptual mechanism where giving a verbal description of a complex stimuli (for example: a human face) will lower the precision of the visual memory of the said thing. It has been reported to occur in connection with many different types of stimuli: images, music, colors but also smells and tastes. Verbal overshadowing has been studied for many years, with the groundbreaking study by Carmichael from 1932 that first showed that introducing a verbal description can interfere with the encoding of the visual part, allowing for many studies that followed this trail in order to uncover the applied implications.

The suspected mechanism that perpetuates this phenomenon is a discrepancy between our proficiency in creating visual memories and our ability to verbally describe things. When the pictures inside our minds often have vivid colors and great detail, we struggle to convey all of those things with words. And as it turns out, once we explicitly try to describe the images verbally, we muck up the source memory itself. After we hear our description of things, we simply cannot get rid of the influence it has on the memory, even if we have really struggled to find the right words to apply. More information about the mechanism itself: https://link.springer.com/article/10.3758/BF03201107

The biggest real-life consequence of the Verbal overshadowing is in police forensics. In general, the more research we do, the more we realize that eye-witnesses, once thought to be ironclad, are actually subjects to so many perceptual distortions and effects that anything they say should not be treated as evidence, maybe a mere guidance at best. VO is most prominent in the situation where a witness/victim has to recognize a face from a line-up. If a verbal description of a suspect is asked to be given before the actual line-up, chances that the memory of a face, once so vivd, is now a murky portrait derived from our own words.

Transcranial Magnetic Stimulation

     Transcranial Magnetic Stimulation (TMS) is a relatively new and exciting technique that utilizes magnetism to interfere with the electricity in our brains.
With a use of a wand-like handheld device connected to a specialistic apparatus, scientists are able to apply just the right amount of force to a precise location on a cranium in order to obtain a particular and expected result. Due to advances in brain mapping, the accuracy of these experiments is astounding.
What effectively happens, is that the part of the brain that is being subjected to the magnetism becomes a functional brain lesion. Of course there is no permanent or physical change, and any effects disappear as soon as the wand is moved away from the subject.

Here is a quick presentation from BBC:

Since TMS is so new, the focus is on its medical uses. Some promising results have been shown in cases involving chronic depression, pain and insomnia. The repeated session are usually the last resort, but if the medication and therapy both fail, there is always another hope that should not be discounted.
More and more insurance plans cover TMS for regular patients.

In connection to our class, the TMS was introduced as a mean to test how different parts of the brain take part in the formation of our perception. From the research standpoint TMS could be revolutionary, but it is not widely adopted in that capacity yet. Just imagine all of the perceptual experiments a scientist could perform with a precise control over the brain at any given moment. A whole new world of really precise measurements is right there, and I am sure that with time it will become more and more popular in both the laboratories and spa-like therapy resorts across the world.

                                                                 Proustian Hypothesis

 

The power of smell is a powerful cue for the recall of vivid personal memories and has come to be known as the Proustian Hypothesis. There have been multiple studies conducted on this topic. Rachel Herz at Brown University conducted one of them. In one study, subjects were asked to describe events from their lives that are associated with campfire. While describing a camping trip that subjects took with their families, they then were asked to provide a set of ratings for their memories. These subjects in the experiments rated memories as being vivid and specific. They also described how the memories made them feel and to what degree that they are experiencing the event vividly. In another study conducted by Herz and his colleagues, subjects were placed in an fMRI scanner and they were asked to remember personal events based on presentation of an odor or visual cue. 

The odor cue was the scent of a perfume, which the subjects had previously identified as evoking a pleasant, personal memory. The visual cue was a picture of the perfume bottle. As the cue was presented , subjects were asked to consider whether the cue evokes a memory and if so, to think about that memory. The imaging results were clear: the familiar perfume scent cue induced greater activity in a core emotional center of the brain (the amygdala) than the picture of the perfume’s bottle. The results suggest that smells seem to bring vivid memories, and that people relived the event again. I found Proustian Hypothesis very interesting because I have smelled odors and they have brought me memories from the past. I had a cologne a long time ago, and whenever I smell it, it brings me vivid memories from when I was on my 20s (Rosenblum, 2010, p72). 

                                                                              Symmetry

Symmetry is a very complex  and interesting term. When both parts of the human body are equal to each other. For example: If both of your wrist, ankles, and knees are pretty much equally in size, it’s said that they are symmetrical. For a long time there has been a believe that body or face Symmetry can predict human health. There are two types of symmetry, Low and High Symmetry. Low Symmetry is believed to be a predictor of poor genetics, physical and mental health, as well as poor cognitive skill and IQ. On the other hand, it’s also believed that High Body Symmetry is a good predictor that people will potentially have healthy offsprings. It’s obvious that low symmetry is very difficult to detect by looking at a body if it’s symmetric or not with the naked eyes. So, nature has given us the ability to smell body symmetry. Of course it’s impossible to smell body symmetry of a person’s wrist for example. It turns out that women on their fertile phase can smell the odor effects of physiological processes related to a man’s body symmetry. Amazing as it sounds, a women on her fertile phase, finds that a symmetric male smells better. A woman who is not on her fertile phase does not have these preferences. Also, women on their fertile phase rate the odor of more dominant males as sexier than the odors of less dominant males. So, if you are a male with High body Symmetry, you are more likely to have luck finding a romantic partner (Rosenblum, 2010, p93). 

                                                                             Pheromones

 

Pheromones are chemicals substance produce and released into the environment by an animal,  especially a mammal or an insect, affecting the behavior or physiology of others of its species. Pheromones are divided into two types: Releaser and primer pheromones. Releaser pheromones are the chemical signals by one animal that, when detected by another animal of the same species, cause it to immediately perform a set of behaviors. The fear scent that induces spontaneous scattering of ants would be an example. Also when the secretion of a male pig’s saliva that cause a female in heat to assume a submissive copulatory position. Primer pheromones are the chemicals signals that induce more long-term physiological changes in the receiving animal. The secretion of female fish that stimulates sperm production in males constitutes a prime pheromones, as does the chemical that induces the aforementioned menstrual cycle synchrony in cohabitating mice. 

There have been claims by the fragrance industry that synthetic pheromones can change our sexual behavior. There is no scientific evidence that support all these claims. There is one possible human chemical signal that could act as a single pheromone. New infants are able to tell the smell of there mother’s based on the secretion from the gland around the nipple. Research on these infants suggests that the odors of a mother’s nipple can induce an automatic behavior in her infant. How we typically evaluate human and animal behavior has led  some researchers to a revised definition of pheromones.

 

https://youtu.be/f-Oupk_4VVo