Reading Activity Week #15 (Due Monday)

1a) The first topic that I found interesting was the section over olfactory physiology.The olfactory sensations are called odors and odorants. Odors are the translation chemical stimulus into a smell sensation. A odorant is a molecule that is defined by its physicochemical characteristics, which are capable of being translated by the nervous system into the perception of a smell. To be smelled odorant molecules must be able to float through the air and must be repellent to water. However many molecules that would seem to meet the basic requirements still don’t smell to us.

1b) I found this section to be interesting as we start to introduce the way we smell. But more specifically I found it interesting that we often don’t smell molecules that meet the basic requirements. The example that is given in the book is natural gas (methane), our evolutionary ancestors would have had no reason to detect these substances which are not dangerous in nature but because the buildup of carbon monoxide in enclosed spaces such as our homes can be fatal we often smell as rotten eggs that act as a warning signal when a stove’s pilot light goes out. I think that this is very interesting that over time we have developed these sense so that we are able to detect these warning signs that our ancestors may have never smelt before.

2a) The second thing that I found interesting was the section over the feel of sent. It was mentioned at the beginning of the chapter that odors have a feel to as well as a smell. Most odorants stimulate the somatosensory system to some degree when passing through the polymodal nociceptors inside the nose. Like ammonia when one smells it, we often feel a burning sensation. These sensations are mediated by trigeminal nerve which is the fifth pair of cranial nerves which transmit information about the “feel” of an odorant as well as pain and irritation sensations.

2b) I found this section to be interesting because I have never really stopped to think that I can actually feel something that I am smelling. But when the book gave the example of ammonia it made me actually think about the smell of bleach actually kinda makes you have a burning sensation and sometimes can make you feel pain in your head… well for me it triggers my migraines and will cause me severe pain from the “smell/feel” of bleach.

3a) The third section that was very interesting to me was the section over odor imagery. One section where olfaction and our other senses diverge is imagery. We know about the visual and auditory imagery is easy and readily accessible, and through in somewhat different ways. By contrast humans appear to have little or no ability to conjure “odor images.” Brain-imaging studies have shown that many of the same parts of the brain that would be involved in actually seeing the kiss are also involved in visually imaging it, however similar studies suggest that the degree of overlap between smelling an odor and “imaging” it is much weaker.

3b) This was particularly interesting to me because I thought that more of our olfactory system was connected to our imagery. Cause as you smell a food in a room that you walk into you may be able to see the item of food that is in the room around you. But you may not actually see it but you are able to see the food around you.

4) The section of the chapter that I found the least interesting would have to be the section about the human olfactory apparatus. Unlike the visual and auditory systems, the primary function of the nose is to filter, warm and humidify the air we breath, but inside the nose there are small ridges called turbinates that add turbulence to incoming air causing a small puff of each breath to rise upward. This puff passes through a small space called the olfactory cleft, and settles on the olfactory epithelium. I think this section was less interesting to me because I felt very confused when I first read the information as there was a lot to take in as I didn’t realize that there were so many parts to the nose which then goes to a different part to produce smell. This just became very confusing to me.

5) I think that the main human olfactory apparatus is the most important that is related to the understanding of sensation/perception. I think that this is the most important to understanding the sensation of the olfactory system as the sense of smell is a large part of your sense and being able to understand it as it is a large system.

6)This chapter builds on from the previous chapter as it goes from touch to the next sense of smell. The previous chapter introduced the sense of touch and we learned how our brain worked to understand the signals of touch this week we looked into how our body understands what we smell.

7) I think that it would be interesting to look into people who lack the ability to sense smell. I think that this would be interesting because of the fact that we often smell a lot of items and can often be used to sense an emergency situation.

8) While reading this chapter I thought a lot about what I was smelling around me. I also thought about how smells that I can actually feel. It makes me wonder a lot about how people live without smell and what would our life be like if we don’t have to smell awful items.

9) Terms: odorants, olfactory physiology, olfactory sensations, odors, auditory systems, visual systems, olfactory cleft, olfactory epithelium, somatosensory system, nociceptors, olfactory apparatus, turbinates, olfactory cleft, olfactory epithelium.

FOR WEDNESDAY

I want to do some research on how we smell for this week’s topical blog. I thought it was interesting that in the twenty first century, we are still not able to find out how odors are being perceived. Perhaps it is harder to measure olfactory experiences, because at times it can be rather subjective. Why are some odor unpleasant and why are others less aversive? How do we distinguish different smells anyways? And what is the relationship between odor and emotions? What happens when one cannot smell?

THEORIES OF OLFACTION

To this day, the way scent is perceived still remains a big mystery for scientists. We are still not sure how scent is perceived, but there are several theories out there suggesting some explanations. The two biggest theories are the vibration theory and the shape pattern theory, and we will focus on those two for this week’s topical blog.

The vibration theory is the more accepted theory of odor and how we smell molecule’s character. Luca Turin proposed that the receptors in the nose respond to the different fundamental vibrations of a molecule and that is how the sensation of smell is produced. Perhaps just like hair cells, rods, and cones, there are a number of different types of receptors responding to different ranges of vibrations. People believe that there are significantly more types of receptors in the nose due to the wide range of smell we are able to perceive. Turin decided that the olfactory receptors have overlapping ranges, but some may disagree. It is possible to have uncovered ranges so that any vibrations in these ranges would produce no olfactory sensations.

The opposing theory to the vibration theory is shape theory. Think of a lock and a key. One key matches one lock and when the lock is unlocked by the right key, it induces an olfactory experience. As the name suggests, this theory proposes that the smell of a molecule is mostly determined by the shape. There is some evidence for shape theory via smell research, stating that there are certain enantiomers that possess identical vibrations but different smells. An enantiomer of a molecule is one that has the same atoms but differs in shape – they are basically identical, but there are certain perks that are different. To prove that shape theory is not adequate to provide an explanation for smell, Turin asserted that the majority of enantiomers have the same smells, and some identical shapes elicit different smells. In other words, this theory contends that a molecule and an olfactory receptor determines which molecules can be perceived as scents, and that molecule must activate the specific olfactory receptors, thus produce the specific patterns of neural activation for each perceived scent. As mentioned earlier, this theory is less accepted than the vibration theory.

EMOTION AND OLFACTION

Fragrances and cologne are popular for a reason – it elicit different emotional responses in different people. Some people prefer a certain kind of cologne, and some other people prefer a softer fragrance. Different smells can elicit different emotional responses. The perception of olfaction does not stop at the sensation of the odor, but extends to the experiences and emotions associated with these sensations. It is undoubtable the smell may elicit strong emotional reasons.
Why? It is because our olfactory receptors are directly connected to the limbic system, which is the most ancient and primitive part of the brain, controls the emotions we feel. Before the cognitive recognition of smell occurs in the cortex, those sensations are processed by the limbic system and produce an emotional response to the smell.

ANOSMIA

There are certain people who can’t seem to smell anything. Some people experience temporary anosmia, and some other experience this disorder permanently. Remember when you were sick you could not smell anything and food became tasteless? Short term anosmia may be caused by inflammation of the nasal mucosa, blockage of nasal passages, permanent anosmia may be caused by the destruction of one temporal lobe. There are certain psychological effects that come with not being able to smell.

People show suffer from anosmia may complain about feeling physical and social vulnerability and victimization. They may also not be able to feel the pleasure of tasting food, thus take away a big pleasure factor in most people’s lives. Not only so, since they are not able to taste food, other problems relating to eating may arise as well. In sum, people who cannot smell may experience feelings of personal isolation, lack of interest in eating and emotional blunting.

http://www.sirc.org/publik/smell_emotion.html

http://sites.sinauer.com/wolfe3e/chap14/chapsummaryF.htm

http://en.wikipedia.org/wiki/Vibration_theory_of_olfaction

http://www.jneurosci.org/content/33/39/15324.full

http://www.sjsu.edu/faculty/watkins/turin.htm

http://www.rsc.org/chemistryworld/2013/01/controversial-molecular-vibration-theory-smell-olfaction

http://en.wikipedia.org/wiki/Anosmia

http://chemse.oxfordjournals.org/content/24/6/705.full

1a) Olfaction and Gustation
1b) This chapter got my attention right away. As soon as I opened the book my attention was brought in to try to figure out what this chapter is even about. Olfaction is a fancy name for one’s sense of smell and gustation is fancy for your sense of taste. These are the two main chemical detection system. One is used for the detection of molecules in the air (olfaction) and the other is the detection of molecules that we put in our mouths (gustation). I’m not quite sure why this caught my attention, but once I learned more about these two seemingly obvious senses and how they work it became more and more interesting to me.
2a) OSN: Human’s vs Bloodhounds
2b) Humans have about 20 million OSN’s (olfactory sensory neurons) split between the epithelia of our left and right nostrils compared to the bloodhounds 220 million. Not only does a bloodhound have more OSN’s than us, five percent of its brain is dedicated to olfactory sensory compared to our one-tenth of a percent. The book discussed the researchers’ thoughts that humans and bloodhounds smell the same smells, but that the intensity to which they can smell is much greater than that of a human. I found this interesting because of the difference between humans and dogs sense of smell. I cannot imagine that kind of intensity with smell.
3a) Trigeminal Nerves
3b) These are nerves in your brain that make you “feel” scents. When you smell mint, you feel cooler. When you smell cinnamon, you feel warm. It also translates pain with things that you smell, like the smell of ammonia burns. I thought that this was so interesting because you do not realize how certain scents make you feel, it just smells like “x.”
4a) Olfactory Apparatus
4b) I know this seems ironic after what I said for my first interesting fact from the book, but I think the reason that I found this the least interesting was because I really do not find the learning of the different parts and how they work very interesting. I am more of a conceptual learner in that I like to learn the basics of how something works rather than the different details.
5) I think the learning of the technical words for smell (olfaction) and taste (gustation) will be helpful in our ability to talk about these senses in a different and more educated way.
6) This chapter is taking us in a new direction. While we have talked about hearing and seeing, we are now moving into smells and tastes.
7a) Trigeminal Nerves
7b) I just think that they would be really interesting to learn more about.
8) One thing that I thought about while reading about these nerves was the effect of smelling coffee. When you walk into a room and you smell coffee, you immediately feel more energized. I wanted to find out if this is due to expected outcomes or these trigeminal nerves.
9) Key terms: Olfaction, gustation, smell, taste, sense, chemical detection, attention, olfactory sensory neurons, epithelia, nostrils, intensity, trigeminal nerves, olfactory apparatus

1a) What did you find interesting?
a topic that i thought was interesting was Lordosis
which is basically the position that females of some species need to assume in order to be impregnated, it involves the inward curving of the spinal column.

1b) Why was it interesting to you?
i thought it was very interesting because compare to humans, where humans could be in any position and have a baby, but in order to be in a particular position in order to conceive, i think that that's very unique.

2a) What did you find interesting?
another thing that i thought was also interesting was Aromatherapy, which is the contention that odors can influence, improve and alter mood, performance and well being as well as the physiological correlates of emotion such as heart rate, blood pleasure and sleep.

2b) Why was it interesting to you?
i thought this was very interesting because i personally think that i have a strong sense of smell, when i'm in a restaurant, if that restaurant smells in anyway unpleasant than i am more likely going to walk out of that because if it smells unpleasant the food will likely be the same and that's what my brain tells me.

3a) What did you find interesting?
the third thing i thought was interesting was Gestation

3b) Why was it interesting to you?
Gestation is basically a fetal development during pregnancy, i thought this was interesting because i've had friends, even my mother admitted this to me, that when you're pregnant, your sense of smell gets stronger than it once was, the thresholds gets triple than what it was before, what i want to know is that whether that process is happening because the fetus which eventually becomes a baby, is affecting that just so they could smell too.

4a) What one (1) thing did you find the least interesting? i thought this chapter overall was not that bad, it was very informative, however something that i didn't quiet understand was releaser pheromone.

4b) Why wasn't it interesting to you?
something i thought was misunderstanding to me and that i could learn more about that i found least interesting was releaser pheromone is basically a pheromone that triggers an immediate behavioral responses it states

4b) Why wasn't it interesting to you?
i think it actually was interesting, i mean i read the information about it, but the whole time i was reading that part of the chapter i felt as if i didn't get the information, the examples and the terms they were using were a bit confusing and i think it lingered more than it actually needed to be, i think that it could've been more complex and i would've had a better understanding about it.

5) What did you read in the chapter that you think will be most useful to in understanding Sensation / Perception?
when reading this chapter, i was thinking back on how when my mother cooks a meal that i am often familiar with, i likely know it right away when i walk near the kitchen or when i come home, i recognize the smell right away and i know exactly what i am going to be eating. I also found out that your odor or the smell you choose to like are based upon your personality, someone like who's a pretty big extrovert, like light smells, flowery smells, that are sweet and soft like lavender, while people who might be on the other side of the fence, they actually prefer darker, stronger smells, the one that lingers, the ones that you could smell about five or seven feet away, i thought that was something pretty interesting.

6) How, in what ways, does this chapter relate (build on) to the previous chapters?
this chapter relates to the last chapter because last chapter basically was talking about touch and how important it is, i think that it builds on to this chapter because touch and smell kind of go hand in hand, likely when you see an object you mostly smelled it first, most people who have a strong smell, they also smell everything even the slightest odor, i think that smell is as important as touch if not more, and smelling something leads to touching it and wanting to see how it feels or what is the texture of the object, i think smell is a huge part of our functional processing on the daily basis.

7a) What topic would you like to learn more about?
a topic that i was really interested in was the cribriform plate, which is basically the process of the smell leaving the external world into your brain internally to process the smell through your receptors and correlates information.

7b) Why?
i'm interested in this because this year i got a cold at least twice or three times, and for each time, i knew when i was losing my sense of smell, my cribriform plate was in trouble, and i want to know whether the tiny bony holes were covered by the disgusting bacteria inside my nose which would result in blocking the receptors to receive the outside smell and brings it to my brain and function that information would get there or what causes people who have colds to loss their smells. also i want to know how some people can't smell things, whether their cribriform plate wasn't developed from an earlier childhood or actually they once had it and just happen to loss it, im also curious about old age, i know that you loss visual and even sometimes taste buds as well, but can you loss your smell as well with old age, those would be some of the reasons why i am interested.
8) What ideas related to what you were reading (what did you think about) did you have while reading the chapter?
the last chapter was basically educating us on how touch is as important as visual and how some people who actually don't have sight finds life to be just fine because they could recognize many if not all objects by touch, they could even read and processing written information by touch, this chapter talks about olfactory, which in other words is known as the smell, the smell you get from certain things, how someone smell, how certain olfactory tells you alot about others, how sweating is actually a good thing and the odor that comes from you could somewhat tell how healthy you are, i think that these chapter tie together in many ways, but mostly because when you have touch and smell, you don't need visual system, it's a plus that it's there and you're able to use it, but if it wasn't there you wouldn't be missing out on a whole lot, you'd actually be fine being blind and having your sense of touch and sense of smell.

9) TERMS: Visual perception, Olfactory, touch sensory, receptors, odors, olfactory epithelium, releaser pheromone, Lordosis, aromatherapy, Gestation.

1a) The first interesting thin in this chapter I found was on the olfactory cleft which is a narrow space at the back of the nose into which air flows and where the olfactory epithelium is located. The olfactory epithelium is a secretory mucous membrane in the human nose whose primary function is to detect odorants in inhaled air. Located on both sides of the upper portion of the nasal cavity and the olfactory clefts, it contains three kinds of cells olfactory sensory neurons, basal cells, and supporting cells.

1b) All of this chapter is very interesting to me because I have allergies and do not understand the makeup of the human nose. So anything that can help me understand my own nose is very interesting to me.

2a) The second item that I found interesting was on the topic of anosmia. Anosmia is the total inability to smell, most often from sinus illness or head trauma.

2b) This was interesting to me because this was a term my ENT doctor had used when describing my condition two years ago. My sternum was broken and it caused an infection which made it impossible for me to smell. After a surgery I could smell and taste things that I could for many years.

3a) Another concept that was interesting was on binaural rivalry which was also from chapter six in our text. This is the competition between two nostrils for odor perception. When a different scent is presented to each nostril simultaneously, we perceive each scent to be alternating back and forth with each other, and not a blend or the two scents.

3b) This was interesting just because I recalled our early chapter on this subject, and now it made more sense, they even had clearer examples to describe this quality of olfaction.

4a) The least interesting was the tip-of-the-nose- phenomenon.

4b) I did not like this because nobody ever says this in public, unlike the very similar tip-of-the-tongue phenomenon. It just sounded silly to have this phrase with smell. That and I can honestly say that I have never had this happen to me, which also may be because of my bad nose, but still it just doesn’t sound like an appropriate name for this concept.

5) The most useful part of this chapter is the layout of the nose and how we smell different scents. This helps us better understand our sense of smell and how exactly it works.

6) In previous chapter we had learned about other senses and occasionally we would learn little bits and pieces about olfaction, now we are able to learn about it as the main topic. So the other chapters did a good job of preparing ourselves for this chapter.

7a) I would like to learn more about anosmia or aromatherapy.

7b) As I have previously stated I once suffered from anosmia when I lost my sense of smell for a period of time, also I like the idea of aromatherapy and would like to know more.

8) This chapter really made me stop and smell the things around me. The room I am currently in smells a bit musky mix with dust, which I should probably clean, but it made me think about how these odors must travel to their appropriate receptors in order to create this scent.

9) olfactory cleft, olfactory epithelium, olfactory sensory neurons, basal cells, supporting cells, anosmia, binaural rivalry, tip-of-the-nose- phenomenon, smell, nose, olfaction, receptors, aromatherapy

1. The first concept from chapter 14 that I found interesting was the concept of anosmia. Anosmia is the total inability to smell, most often resulting from sinus illness or head trauma. A person's sense of smell is driven by certain processes. First, a molecule released from a substance has to stimulate olfactory cells that are found higher up in the nose. These nerve cells then send information to the brain where the specific smell is identified. Anything that interferes with these processes lead to loss of smell. The ability to smell also affects our ability to taste. Without the sense of smell, our taste buds can only detect a few flavors, and this can affect one’s quality of life. I find this interesting because I cannot imagine what it would be like to lose my ability to smell. My life would be so much different and reading this section in our book really made me think about my life without one of the five senses.
2. The second concept from chapter 14 that I found interesting was the concept of binaural rivalry. This is when the two nostrils are in competition for odor perception. The book states, “When a different scent is presented to each nostril simultaneously, we perceive each scent to be alternating back and forth with the other, and not a blend of the two scents.” Some of our sensory organs come in two pairs such as our eyes, our ears, and our nostrils. Typically each side has differences. It is our brain’s job to generate stable representations for each of our organs. I found this interesting because I had never read anything like this before about binaural rivalry. Knowing that my nostrils are in competition to breathe in different scents is amazing to me.
3. The third concept from this chapter that I found interesting was the tip of the nose phenomenon. This is the inability to name an odor even though the odor is very familiar. Anthropologists have actually found that there are fewer words for experience of smells compared to other sensations. I found this concept to be interesting because I had never fully thought of this idea. I had also never heard of this term so when I first saw it I was excited to read about it. I found this interesting because I believe this happens a lot to people. Many times I am trying to think about where I smelt something, or where I have seen something but I just cannot come up with the answer.
4. What I found the least interesting in this chapter was all of the chemistry put into it. There were so many terms about cells and neurons and I could not keep up with all of the concepts. There isn’t one particular concept that I disliked the most. I would say that a majority of the chapter was not very interesting simply because I do not have the brain for chemistry. A lot of it was confusing and I had to reread a couple of the sections just to get the slightest idea of what it was talking about.
5. I think the section on olfactory philosophy is the most useful to understanding the concepts of sensation and perception. Olfactory sensations are called odors and these chemical compounds are called odorants. This is important to know because it is all about the sense of smell. Knowing these basic terms is one step closer to understanding sensation and perception.
6. This chapter builds off the previous chapters because we have mainly focused on our five senses as humans and we have talked about sound, sight, and touch and now we are talking about smell. All of these go hand in hand because in some way our brain is involved. I feel like all of these are just as important as any other part of our body because all of these make up an individual. These chapters continue to give a lot of detail about each sense that we have yet there is so much more to learn.
7. I would like to learn more about scents and how we experience and process them. Odorants stimulate the somatosensory receptors inside the nose and these sensations are arbitrated by the trigeminal nerve. Trigeminal stimulation accounts for why our eyes react to each situation we are in. This was all very interesting to me and I feel like this chapter only goes slightly into detail about it. After reading about it and reading this chapter I would like to learn more about these concepts.
8. I really only thought about what I was reading this whole chapter. Not a whole lot came to mind unless I was reading about something I was familiar with because then I could relate specifically to one experience or so. Even reading about concepts that I didn’t know I thought about a few things but nothing really overtook my mind while reading the chapter.
9. Terms: Sensation, perception, anosmia, binaural rivalry, nostril, olfactory cells, somatosensory receptors, cell, neurons, sound, sight, touch, smell, five senses, olfactory philosophy, tip of the nose phenomenon, molecule.

1. The first thing I found interesting was olfactory hedonics. Olfactory hedonics is the immediate evaluation of whether or not we like a smell. This is typically done by examining three aspects of the smell in question: pleasantness, familiarity, and intensity. Pleasantness is simply how much we like the scent at first. The more familiar we are with a scent: the more likely we are to find that scent pleasant. This relationship between pleasantness and familiarity is a linear one. In the same thought, unfamiliar scents are more likely to be perceived and unpleasant. The intensity of a smell is more complicated than pleasantness and familiarity. This complexity can best be explained by comparing the type of relationship, and that is an inverted-UB (aka an upside-down U). A smell starts out as neutral but as it is noticed more, it becomes more pleasant. There is a threshold when a pleasant scent becomes unpleasant, which is at the peak of the inverted-UB. Basically when the pleasant scent sticks around for too long, it becomes more intense. That is usually when a scent a person likes can become unpleasant. I thought this was interesting because it talked about the basis for why we like the smells we like.
2. The second thing I found interesting was the nature verses nurture debate about the origin of the hedonic odor response. The nature side of the debate states that humans are born with a set list of good and bad smells. As far as can tell there in not much research to back this point of view because there is very little proof of how much fetuses are exposed to scents while in gestation. The olfactory system in humans is fully operational 3 months into gestation. Some evidence points toward fetus’ developing their preferred smells via the foods their mother eats during gestation, but this doesn’t perfectly apply as there is only a little evidence that says that infants preferred food choices are linked to foods their mother ate before they were born.
There seems to more evidence pointing towards the nurture side of this debate. People who think this side is correct would probably agree with the evolutionary argument. This argument basically says that the first experience an animal has with a smell defines how they will categorize that smell for the rest of their life. When the smell in question is associated with a reaction, good or bad, the response is stored in the brain. When that smell is sensed again, the amygdala-hippocampus complex sends a neural message that can be positive or negative. When that message is negative it is called learned taste aversion. One example is that if a person were to eat a poison berry, they would associate the negative symptoms with that berry and would not want to eat it if they ever came across it again. This could also be used as protection from environmental factors (like the smell of smoke or the mechanical integration of fire and skin) that could be dangerous. For example, the California Ground Squirm associates the smell of a Rattler with danger and fear since the squirt is lower on the food chain. I thought this topic was interesting because nobody knows which side of the debate is correct for a fact, and I doubt people ever will.
3. The third thing I found interesting was the idea of cognitive habituation. Cognitive habituation is the process of a person’s sense of smell adapting to a certain smell after a while. This happens because receptor adaptation is a thing. Basically this means that if a person is around a smell long enough, they would stop being able to smell it because the receptors became less sensitive to the smell. Interestingly, if a person were to remove themselves from this smell and return , the scent would be just as strong as it first was because it would be a ”new” scent. I thought this was interesting because I didn’t know the name for cognitive habituation but it was something I did all the time.
4. I thought the bit on the individual parts of the olfactory system was boring because it was very technical.
5. I think cognitive habituation is the most important part because it is something that is good or bad depending on what the smell in question is.
6. This chapter talked about the amygdala-hippocampus complex, which was talked about in the brain chapter.
7. I would like to learn more about which scents bug people most often and if it is possible to become so used to a smell that you can’t smell it at all. I get headaches from most perfumes and any cigarette smoke.
8. I thought about what I talked about in number 7.
9. Terms: olfactory hedonics, evaluation, pleasantness, familiarity, intensity, Scent, relationship, linear, unpleasant, inverted-UB, neutral, threshold, nature verses nurture debate, hedonic odor response, humans, good, bad, olfactory system , preferred smells ,evolutionary argument, associated, amygdala-hippocampus complex , brain, neural message, learned taste aversion, poison, negative symptoms , environmental factors mechanical integration , food chain, gestation, cognitive habituation, sense of smell , adapting, receptor adaptation , sensitive.

(1ab) The first topic I found interesting was the main subject of this chapter, Olfaction. Olfaction is part of the human chemical detection system responsible for molecules in the air. It is our sense of smell! This topic was interesting to me because the power of this system is under appreciated. The human smell is so strong and powerful that it can trigger emotional responses to certain smells at times, it can also recognize a smell from the past that may trigger an intensely detailed flashback of a memory way back when. When you describe and applaud our smell like that, its hard to understand that at times it can be difficult to name the most familiar smells. Olfaction “our sense of smell,” also has a hard time when multiple molecules are mixed together, the resulting smell gets perceived as qualitatively different than the smells of any of the component molecules by themselves.

(2ab) I found the topic of olfactory habituation interesting. It was interesting to me because my mom was always over excessive about having our house smell good. She would always go to the store and spend more money on the product that supposedly lasted the longest. So if you buy a certain product with a pleasant fragrance, the moment you come home and can’t smell it anymore you throw it away right? Well if the smell is supposed to last more than a few weeks your olfactory system may undergo some transformations. The adaptation mechanism experienced when you smelled the product at the store, soon becomes non-existent. Your receptor proteins become so exhausted that they stay inside their cell bodies, therefore adapted to the odorants. The end result is habituation, yes you will smell some molecules but your brain will begin to not process it.

(3ab) The work done by Herz interested me. Odors were known for being the best cues to memory but were they? Herz addressed the question comparing recollections stimulated by a familiar smell. Herz used popcorn with memories evoked by by the sight of popcorn, the sound of popcorn popping, the feel of popcorn kernels, and simply the word popcorn. This was interesting to me because the results showed that memories evoked by odors were equal to the memories evoked by sight, sound, feel, or words. But what was found was that a recollection triggered by odors, were more emotionally intense memories compared to memories triggered by other forms of modality. This emotional potency of odors goes on to back the perception of odors and the benefits of aromatherapy.

(4ab) I really didn’t find the topic of odor mixtures very interesting. It wasn’t interesting to me because I have noticed in myself that I do not have the ability to smell odor mixtures and decipher which is which. It also didn’t appear interesting to me because it says that analytical olfactory ability can be achieved and developed with training. No matter what training you get, I do not see a person obtaining the ability to pick out certain odors associated with mixtures. This task to me just seems unachievable.

(5) Further developing my understanding of sensation and perception was achieved when I read that chemical sensing systems like olfaction, gustation, and trigeminal nerves all enable us to feel gustatory and olfactory experiences. Certain memory cues can trigger emotional, evocative, vivid, and specific responses to the human body.

(6) Previous chapters have went on to describe and educate us on what enables us to survive in our environment. Like perception, touch, hearing, vision, motion, the ability to smell and taste (olfaction) is just another important piece of the puzzle on how we use our senses to get through life and survive.

(7ab) I would like to learn more about odor habituation and adaptation. I would like to learn more about this topic because this chapter made me realize that if it only takes a few weeks to adapt and habitualize to certain odors, how can we know or become aware that the air we breath could be a toxin or something in your home could be toxic. As humans, our bodies and our senses are subject to a lot of different parts of our environment, some good, some bad. How will we know which is which? Do we even know which is which?

(8) I thought about how the smell and odor of a certain garment can be pleasant. After my sister passed away, I now sleep with one of her blankets because the odor provides me with a certain smell that calms me down emotionally and provides vivid memories I had with her. I also thought about the idea of habituation and adaptation with the smell of pets. I always hear friends and family that come over that it smells like dog but I do not smell the odor. I now realize that after having the dog for so long I am adapted to the odor so my receptors are now closed to that stimuli so I am unaware that it stinks.

(9) Terms : olfaction, gustation, odor, odorant, olfactory receptor, olfactory nerves, olfactory habituation, olfactory adaptation, aromatherapy

1a. The first concept that I found interesting from chapter fourteen was the section on the feel of scent. Human beings often experience odors as having a particular feel to them because they activate the somatosensory system through specialized receptors that perceive touch and pain. These sensations are also mediated by the trigeminal nerve that is responsible for why our eyes water when we chop onions and eat an extremely spicy pepper.
1b. I found this topic interesting because I am hispanic and often eat foods that are extremely spicy and result in my mouth burning and my nose running. I have always wondered what parts of my physiology are responsible for this physical response to the spicy foods. I also think it is interesting that the authors addressed the ability of humans to feel a scent because I have experienced this many times when I am cooking but I did not know if it was a real phenomena.
2a. The second concept from chapter fourteen that I found interesting addressed cognitive habituation. It is the psychological process of losing the ability to detect an odor after being exposed to it for a prolonged period of time. We learn to habituate to stimuli presented to all of our senses but we experience this more so with sense of smell. It takes weeks of removing an order from our daily lifestyle for us to be able to recognize the smell as novel again.
b. I found this topic interesting because I have experienced it in my life many times. I worked in a bakery for two years and I often noticed that when I walked into the bakery I experienced very strong smells of cake and other various items, but after working for an thirty minutes I could no longer smell the pungent bakery smells that bothered my nose when I first walked in. I have also experienced this with perfume. After wearing my favorite perfume a few times I was unable to smell it and as a result I kept putting more and more on because I thought it wasn't strong enough. In reality it was plenty strong, I just habituated to the odor and could no longer smell it on myself.
3a. The last concept from chapter fourteen that I really enjoyed was the section that discussed the nature and nurture of odors and the role of gestation in the development of favorable odors. Research has found that the olfactory system is fully developed by the third month of pregnancy. This is interesting because researcher have also discovered that mothers who consumed strong smelling volatiles such as garlic, alcohol, and cigarettes during pregnancy gave birth to infants that showed greater preferences for these strong smells. These preferences facilitated during birth often influence the taste and food preferences of children into adulthood.
b. I found this topic extremely interesting because it provided great evidence on the affect that mothers have on their children during gestation. It is fascinating that the odors mothers share with their children during pregnancy result in smell and food preferences of a child later in life. It makes me wonder if my parents affinity for mexican food during my moms pregnancy with me is the reason why I am so in love with mexican food.
4ab. I did not find any of the information in this chapter to be boring but I found the triangle test and the G protein-coupled receptor to be difficult to initially read about. I do not have extensive knowledge about the receptors of the olfactory system and I am not particularly interested in learning about the triangle test that asks participants to identify odd smells.
5. I think the information on the parts of the olfactory system and the phenomenas of habituation and taste aversion will be very useful for my continued knowledge of sensation and perception. It is important that I am aware of the important aspects of the olfactory system and the affects that our environment and our body have on the effectiveness of this important system.
6. This chapter addresses a new topic related to sensation and perception but it follows the same general format as the previous chapters dedicated to other systems of the sensation and perception system. It addresses the important parts of the olfactory system as well as interesting phenomenas that occur within the system and affect our physical experiences. In this way, chapter fourteen builds off of the previous chapters of this textbook.
7ab. I would like to learn more about learned taste aversion. It occurs when an individual avoids a novel flavor after it has been paired with a gastric illness. Interestingly, it is the smell and not the taste that is the key for the learned aversion. I am interested in this topic because I have experienced this many times when I eat a food and then develop the stomach flu. I don't often crave foods that I threw up after getting sick because the smell was nauseating. I am also interested to learn if this topic is related to the idea of biological preparedness.
8. While reading this chapter I thought about the foods that I cook with or eat that evoke specific feelings and reactions from me. I also thought about the smells that I have habituated to after long exposure and the foods that I have a learned taste aversion to after experiencing sickness paired with the food.
Terms: olfactory system, smell, somatosensory system, trigeminal nerve, cognitive habituation, stimuli, odor, gestation, triangle test, G protein-coupled receptor, learned taste aversion, biological preparedness,

1a & b) What did you find interesting? Why? The first item in this chapter I found interesting was specific anosmia. Specific anosmia is defined as the inability to smell one specific compound amid otherwise normal smell perception. Specific anosmias are usually due to faulty odorant-receptor interactions and not odorant vibrations. An odorant is a molecule that is defined by its physiochemical characteristics, which are capable of being translated by the nervous system into the perception of smell. I found this interesting because of the statistics of the people that have this ability. A significant proportion of the population has a specific anosmia to androstenone (between 11%-75%) Most of the specific anosmia’s are due to a genetics.

2a & b) What did you find interesting? Why? The second item in this chapter I found interesting was pheromones. Pheromone is defined as a chemical emitted by one member of a species that triggers a physiological or behavioral response in another member of the same species. Pheromones are not odors, instead they are chemicals that might or might not have a smell. I found this interesting because I had thought originally the mammals were the only species that used this system. In fact, pheromones are used mostly by insects; ants, termites and bees. In the animal kingdom pheromones are used to mark another animals territory. Pheromones have 2 types of effects: 1) releaser pheromones and primer pheromones. Primer pheromones effects are slow and produce a physiological change in the recipient over times. Releaser pheromones triggers an immediate behavioral response among conspecifics.

3a & b) What did you find interesting? Why? The third item in this chapter I found interesting was the tip-of-the-nose phenomenon. This phenomenon is defined as the inability to name an odor even though the odor is very familiar. I found this concept to be interesting because I had never fully thought of this idea. Anthropologists have actually found that there are fewer words for experience of smells compared to other sensations. I found this interesting because I believe this happens a lot to people. I would like to know why and what are some smells that occur that spark some kind of memory.

4a & b) What one (1) thing did you find the least interesting? Why? The part of the chapter I liked least was the section on chemistry to smell. I don’t have much of a background in chemistry, so most of the concepts and theories were hard to follow. I understood the overall concept of it, but some of it was pretty confusing as well, the terms and so on. All the theories, such as shape-pattern theory or vibration theory, have so many different molecules that can be a receptor. This makes it difficult to keep them all in order.

5) What did you read in the chapter that you think will be most useful to in understanding Sensation/Perception? I think one of the most important concepts to learn in this chapter is receptor adaptation. Receptor adaptation is the biochemical phenomenon, occurring after continual exposure to an odorant, whereby receptors stop responding to an odorant and detection decreases. I think this is important in understanding perception and sensation because it may have an impact of survival for any species. If our olfactory system gets used to a certain odorant, it may put us in a disadvantage for threats.

6) How, in what ways, does this chapter relate (build on) to the previous chapters? This chapter builds off previous chapters by, previous chapters we had learned about other senses (sight, touch, hearing, etc.) and occasionally we would reference something about olfaction. We can now learn about olfaction as the main topic. Each chapter either mentions what we will be studying next, or the chapters always refer back to one of the other senses we learned, and how all the systems tie into one another.

7a & b) What topic would you like to learn more about? Why? I would like to know more about the nature vs. nurture debate. For decades, a debate in olfaction culminates around the innate side of the of debate claim that we are born with a predisposition to like or dislike certain smells. On the other side of the spectrum, researchers are also looking at the learned view. These researchers believe that we are born merely with a predisposition to learn to like or dislike smells, and that, that smell is either liked or disliked depending on an emotional value of the experience that we have been associated with. I would also like to know what parts of the brain are more active when we smell something familiar and it brings back memories.

8) What ideas related to what you were reading (what did you think about) did you have while reading the chapter? Not a whole lot came to mind while reading this chapter. If I were to pick one thing that possibly came up more than any other thing in this chapter, I would say that it’s interesting to think about the science of learning about the olfactory system and structures. To think about the research and test the theories behind many of what we read in the book is very interesting.

TERMS: anosmia, perception, odorant-receptor, odorant vibrations, its physiochemical, androstenone, pheromones, releaser pheromones, primer pheromones, tip-of-the-nose phenomenon, sensations, shape-pattern theory, vibration theory, receptor adaptation, odorant, odor, olfactory system, olfaction,