Sunday, December 10, 2017

What's that ringing?

Have you ever been sitting in a quiet setting when all of the sudden this faint ringing starts to sound in one or both of your ears? Tinnitus is that ringing, buzzing, or hissing sound one usually gets randomly, but to some the ringing happens on a much more regular basis. Even as I write this in my quiet room I hear a high pitched ringing sound in my right ear. Tinnitus does not cause hearing loss, nor does hearing loss cause tinnitus, but they are associated with one another. In fact, sometimes tinnitus can allow an increase in hearing so much that a person has to take measures to muffle external noises. Tinnitus can be caused by an infection or blockage in the ear, but it usually sticks around even after treatment. Furthermore, therapies are available to help decrease those annoying sounds but in the mean time I'll just be doing my best to ignore it!

Friday, December 8, 2017

The Quietest Place on Earth

Image result for quietest room in the world

The quietest place on earth is a laboratory in South Minneapolis, at Orfield Laboratories. The room cancels 99.99 percent of all sounds and is the present holder of the world record for world's quietest place at an ambient sound level of -9.4 dBA. While the room is typically used for product testing (to measure the level of sound emitted from LED lightbulbs or cell phone screens), people are also allowed to sit in the room to experience the lack of sound. The room, through the use of sound-absorbing material on all its surfaces, is so quiet that a person inside can hear their heart, stomach, ears, and other internal organs. The experience is disorienting, and anyone who wishes to spend an extended period of time in the room must be seated to prevent the person from falling over. The longest anyone has spent in the room is 45 minutes, and the creator of the room himself has only spent 30 minutes in the room.

Link: http://www.dailymail.co.uk/sciencetech/article-2124581/The-worlds-quietest-place-chamber-Orfield-Laboratories.html

Thursday, December 7, 2017

Phi Phenomenon

woman listening to music


Does the picture seem like its rolling or moving?

Animation, films and online video all depend on optical illusion known as the phi phenomenon. 
The phi phenomenon is a perceptual illusion in which a disembodied perception of motion is produced by a succession of still images. The visual system doesn't really see motion at all it sees edges at different positions in space and makes the assumption that they are moving, like the picture above its just a still image but that way its positioned, the lines and spaces makes it seem like its moving.

Reference
https://www.scientificamerican.com/article/reality-check-10-practical-applications-of-illusions/
The Jelly Bean taste test

Savory Science: Jelly Bean Taste Test
When taking a bite of food, receptors in your mouth called taste buds pick up the taste of the food you are eating. These receptors have five basic tastes: umami, salty, sweet, bitter and sour. The nose also plays a part in how you experience food. It has millions of receptors of odor molecules. The latter occurs because the back of your throat connects your nose and mouth. That air needs to be flowing in or out of your nose for the odor molecules to get into the nose. Odor molecules travel to your nose's olfactory epithelium, the area of the nasal cavity where odor detection occurs. While you are eating, your brain receives signals from both your mouth and nose, allowing you to recognize whatever tasty treat you happen to be chewing. The jelly bean test helps separate taste and smell.
This test is done by blindfolding a partner, then giving them a jelly bean then asking them to chew it and guess its flavor. Then they have to repeat it and this time they have to pinch their nose and say what flavor they taste.

The results of this test was that when you cannot smell the jelly bean you are eating, you can only taste the sweetness, but you can not tell which flavor you are chewing. This demonstrates how much we rely on our sense of smell when tasting food.

References
https://www.scientificamerican.com/article/bring-science-home-jelly-bean-taste-smell/


Why does your dogs eyes glow?

Image result for why dogs eyes glow

Have you ever wondered why animals or your dog has a glow in their eyes at night?
I have always wondered why both my black labs eyes have a green glow in the dark.

In the dark, their eyes react to exposure to light differently than our eyes. Dogs (along with cats and other animals) have a light-reflecting surface known as the tapetum lucidum, located between the optic nerve and the retina. It reflects the light and allowing the rods and cones to pick up the limited amount of light available at night.
This is a feature in animals who tend to be hunters at dawn and dusk. The eyes of these animals are geared for low-light vision. They include dogs, cats, cattle, deer, horses and ferrets.
We don't have this feature since we do not have the tapetum lucidum and mostly since we are more active during the day. The glow varies by animal and the amount of zinc or riboflavin present in pigment cells within the tapetum lucidum. The animal’s age, color of his coat and eyes, can also influence the glow. The age can change reflectivity as the lenses become denser.
Most dogs are born with blue to purple tapetums, but the color shifts by 16 weeks of age. It is said that adult yellow Labradors tend to have light yellow-colored tapetums and black Labs tend to have deeper yellow or green-colored tapetums. Dogs with white coats and blue eyes can give off a red-eye effect in dark settings. The red-eye look is due to blood vessels in the eyes that reflect when exposed to light.
Reference
http://www.vetstreet.com/our-pet-experts/why-do-my-dogs-eyes-glow-in-the-dark

Wednesday, December 6, 2017

Healing Grid Illusion


The image is regular at the center, but the grid pattern is less regular at the peripheral parts of the images (both on the left and right edges). As you stare at the center of the grid for say 20 seconds, the regularity of the grid pattern at the center spreads into the irregular parts in the periphery. This illusion seems to indicate the preference of the visual brain to see regular patterns. An optical illusion happens because the different parts of the eye process images and colors at different speeds, this sometimes means that false images are sent to the brain. The brain receives this information but actually, the eye only sees some visual information at any given time, and our brain processes this and fills in the gaps to give the impression of continuous movement.
Image source:
© 2005 Ryota Kanai

The Illusion of Sex


In the Illusion of Sex, two faces are perceived as male and female. However, both faces are actually versions of the same androgynous face. One face was created by increasing the contrast of the androgynous face, while the other face was created by decreasing the contrast. The face with more contrast is perceived as female, while the face with less contrast is perceived as male. The Illusion of Sex demonstrates that contrast is an important cue for perceiving the sex of a face, with greater contrast appearing feminine, and lesser contrast appearing masculine.

Source:
Russell, R. (2009) A sex difference in facial pigmentation and its exaggeration by cosmetics. Perception, (38)1211-1219.

Fingerprints and Touch


Image result for fingerprints

Fingerprints are one of the more questioned and intriguing parts of the human body. Obviously organs like the eyes and brain are far more advanced and studied more for good reason. Fingerprints are not nearly as exciting or mind blowing as other organs, but the reason we have fingerprints is what's really questioned. Our eyes help us see, our nose helps us smell, our tongues taste, so why do we have fingerprints? Our fingers themselves are used for grabbing and touching, but why the prints? The reasoning originally thought of was friction, which still makes the most sense. The grooves on our fingerprints actually allow us to have more friction when grasping or touching something, which makes things less slippery in our hands. The amount of friction and its usefulness is still being questioned, but without fingerprints it would definitely be harder to hold or grab stuff that has a smooth surface.

Sound Resonance and Glass




Image result for sound shattering glass

Sound can be measured by loudness and frequency. The loudness of the sound is measured in decibels, and the frequency or pitch of the sound is measured in hertz. The frequency of the sound being made can have a lot of interesting effects besides just loudness, which is either loud or quiet. Many people have heard of the notion that if a high pitched sound is played that it can shatter glass. This is true, and due to what we call resonance. Resonance is when at a certain frequency, a vibrating system or force causes another object to oscillate with rapid amplitude. Each glass has different but similar resonance frequency. So, if a sound is played with the perfect resonance frequency matching the glass, in the vicinity of a glass, it can vibrate the glass so rapidly that it can cause it to actually shatter. This phenomena has been tested numerous times and proven true on Myth Busters with an opera singer.

Tuesday, December 5, 2017

Augmented-reality technology could help treat 'lazy eye'


To gauge change in ocular dominance over time, the researchers had participants complete a binocular-rivalry task before the adaptation phase, at the beginning of each training session in the adaptation phase, and at follow-up sessions 24 hours, 2 days, 3 days, 1 week, 3 weeks, 2 months, and 4 months after the last training session. In each trial of the task, the participants saw two images simultaneously, one presented to each eye. Each image featured a striped grating pattern, with the pattern in one image oriented in a different direction from the pattern in the other image. After seeing the images, participants pressed a key to indicate the direction of the pattern they saw (tilted counterclockwise from vertical, tilted clockwise from vertical, or mixed).

When different images are presented to each eye, people tend to perceive the images as alternating back and forth and they typically report seeing the image presented to their dominant eye a greater proportion of the time. Thus, the task should reveal any changes in ocular dominance over time.

https://www.sciencedaily.com/releases/2017/12/171205115939.htm

Eye Contact With Babies Synchronizes Brain Waves

The team examined the brainwave patterns of 36 infants (17 in the first experiment and 19 in the second) using electroencephalography (EEG), which measures patterns of brain electrical activity via electrodes in a skull cap worn by the participants. They compared the infants' brain activity to that of the adult who was singing nursery rhymes to the infant.
In the first of two experiments, the infant watched a video of an adult as she sang nursery rhymes. First, the adult, whose brainwave patterns had already been recorded, was looking directly at the infant. Then, she turned her head to avert her gaze, while still singing nursery rhymes. Finally, she turned her head away, but her eyes looked directly back at the infant.
As anticipated, the researchers found that infants' brainwaves were more synchronised to the adults' when the adult's gaze met the infant's, as compared to when her gaze was averted Interestingly, the greatest synchronising effect occurred when the adults' head was turned away but her eyes still looked directly at the infant. The researchers say this may be because such a gaze appears highly deliberate, and so provides a stronger signal to the infant that the adult intends to communicate with her.
In the second experiment, a real adult replaced the video. She only looked either directly at the infant or averted her gaze while singing nursery rhymes. This time, however, her brainwaves could be monitored live to see whether her brainwave patterns were being influenced by the infant's as well as the other way round.
This time, both infants and adults became more synchronised to each other's brain activity when mutual eye contact was established. This occurred even though the adult could see the infant at all times, and infants were equally interested in looking at the adult even when she looked away. The researchers say that this shows that brainwave synchronisation isn't just due to seeing a face or finding something interesting, but about sharing an intention to communicate.
https://www.sciencedaily.com/releases/2017/11/171129104230.htm

Monday, December 4, 2017

Tinnitus

A surprising number of Americans have some form of tinnitus; 1 in 5 Americans report having symptoms of it. Tinnitus is the perception of a constant noise in the ears. Most people with tinnitus describe the sound as a constant high pitched “ringing”, “buzzing” or “hissing” sound. Although tinnitus is usually not a serious medical condition by itself it is an extreme nuisance to people who have it. Some people with tinnitus find it difficult to sleep at night or have trouble following conversations.

This video contains a few examples of what people with tinnitus claim to hear in their ears.
                                       
 A common cause of tinnitus is inner ear damage. In the cochlea, tiny hairs detect vibrations in the cochlea fluid and send electrical signals to the brain. In people with tinnitus, some of these hairs are snapped or broken so the hairs constantly send electrical signals to the brain. The reason why people with tinnitus often hear high-pitched sounds is because, the hairs closest to the base of the cochlea hear the highest pitched sounds and they are also the first hairs to get damaged. To prevent tinnitus, it is recommended to avoid areas with very loud noises and to listen to music at a moderate volume.

https://www.mayoclinic.org/diseases-conditions/tinnitus/symptoms-causes/syc-20350156




Humans are born with the ability to recognize snakes and spiders

A team of researchers from Max Planck Institute in Germany and Uppsala University in Sweden tested to see if human infants have an innate fear of potentially dangerous animals. In the test, 48, 6-month-old infants were shown a series of slides that depicted various animals. When the infants saw pictures of snakes and spiders they consistently reacted with dilated pupils. This means that the infants feared the animals and they paid a lot of attention to them. The infants did not have the same response when they were shown harmless stimuli like flowers and fish.
                                               
This study shows that humans are born with the ability to recognize dangerous animals. This is an evolutionary mechanism that helped human infants to avoid interacting with potentially lethal animals. This research also suggests that all infants are born with images of snakes and spiders already hardwired into their brains.