Profile

Cover photo
Sree Harsha D
Works at Fiserv
Lives in pune
779 followers|179,202 views
AboutPostsPhotosYouTube+1'sReviews

Stream

Sree Harsha D

Shared publicly  - 
 
I won candy on the #googlebirthday doodle! Score: 159
1
Add a comment...

Sree Harsha D

Shared publicly  - 
 
I just scored 8,028 points in 7x7! Just try and beat my score http://goo.gl/ytqLu #7x7
1
Add a comment...
Have him in circles
779 people
Padma D's profile photo
Yanu Gupta's profile photo
Guru Mann's profile photo
akhil ambi's profile photo
Manoj Kumar's profile photo
Young Lee's profile photo
MIND's profile photo
Brian King's profile photo
Dorjee Taku's profile photo

Sree Harsha D

Shared publicly  - 
 
Click on the button to get the indicated file format: Format, HTML, Text, WP, PDF, RTF, Word, Image. Local, HTML Version or Menu, Text Version, Zipped WordPerfect, Adobe PDF, RTF, MS Word Version, Graphic Image. Remote, Remote Link - HTML, Remote Link - Text, Remote Link - Wordperfect ...
1
Add a comment...

Sree Harsha D

Shared publicly  - 
 
nice read..
 
Chicken-Powered image stabilizer

As you can see in the gif below , chickens are remarkably good at keeping their head still while their body is moving. They are able to do this when someone else moves their body,  but also when they move themselves. This is why a chicken's head (or a pigeon's head) bobs back and forth during walking: The chicken keeps its head still with respect to the environment by moving it backwards to compensate for the forwards body movement. This continues until the head cannot move back any further, at which point it rapidly snaps forward, momentarily breaking the otherwise near perfect head stabilization .

When you think of it, head stabilization is a remarkable feat: The gravitational (or vestibular) sense is required to keep the head up-right, regardless of the body's orientation. And you also need to take into account the position of the body parts relative to each other, which is called proprioception.

So the obvious question is: Why has the chicken evolved this remarkable ability to keep its head stable? An ability that surely requires a sophisticated neural apparatus.
In fact, this phenomenon is not limited to chickens, or even to birds. Almost all animals exhibit these types of stabilizing reflexes. Some engage their entire head, just like chickens do. Other animals, including ourselves, stabilize only the eyes. This allows us, for example, to keep our eyes fixed on someone throughout a conversation, despite the fact that we regularly nod or shake our head.

But why? Why the need to stabilize the head, or at least the eyes?

The answer lies in the way that the eyes work. Light shines through the pupil onto the retina in the back of the eye. You can therefore think of the eyes as containing a retinal image, formed by the pattern of light falling onto the retina.
But the retinal image has the following drawback: It is anchored to the eye, and therefore it changes when the eye, or the body to which the eye is attached, moves. Therefore, if an animal would not engage in any kind of stabilizing behaviour, all movement would result in disturbances of the retinal image, or retinal image motion.

But this begs the question: What's so bad about retinal image motion?
The first has to do with the sluggishness of the light sensitive cells, or photoreceptors, which form the basic building blocks of our eyes. This sluggishness imposes a fundamental limitation on vision: We cannot see things that are presented extremely briefly or that move very fast. If something flashes by too quickly, photoreceptors are simply not stimulated for a sufficient period of time. We may be able to catch a glimpse of something, but it will be blurry. And if we would not stabilize our eyes (or our entire head), our own movements would cause the world to sweep across the retina very rapidly. So rapidly, in fact, that it would cause blur. In other words, to prevent blurry vision, you should keep the eyes still.

The second reason has to do with the way that we process visual information once it has reached the brain. Or, more specifically, with how we detect motion. If our eyes don't move, motion detection is easy: All movement on the retina corresponds to movement 'out there' in the world. But if our eyes are moving, things become considerably more difficult. Because in that case the entire retinal image is always moving. Considerable computation will therefore be required to distinguish retinal motion that is artefactual, in the sense that it results from our own movement, from retinal motion that is real, in the sense that it corresponds to movement 'out there'.

So, in sum, the head stabilizing behaviour that you saw in the gif  serves an important purpose: It prevents unnecessary retinal image motion, and consequently avoids blurry vision and impaired motion detection.

References : Land, M.F., & Nilsson, D.E. (2002). Animal Eyes. Oxford, United Kingdom: Oxford University Press.
Sebastiaan Mathôt for  Laboratoire de Psychologie Cognitive at Aix-Marseille université.
http://www.cogsci.nl/blog/bird-brains-and-fish-eyes/177-stabilizing-vision-do-the-chicken-head
10 comments on original post
1
Add a comment...

Sree Harsha D

Shared publicly  - 
1
Add a comment...

Sree Harsha D

Shared publicly  - 
 
 
"When I look back on my life, I won’t be thinking about any particular legislation I passed or policy I promoted. I’ll be thinking about Michelle, and the journey we’ve been on together. I’ll be thinking about Sasha’s dance recitals and Malia’s tennis matches – about the conversations we’ve had and the quiet moments we’ve shared. I’ll be thinking about whether I did right by them, and whether they knew, every day, just how much they were loved." —President Obama on fatherhood: http://wh.gov/l3WtB
423 comments on original post
1
Add a comment...

Sree Harsha D

Shared publicly  - 
 
 
An epic sunset from the Eureka Tower in Melbourne, Australia. The windows at the top of the building are gold plated so you get a cool reflection.
82 comments on original post
1
Add a comment...
People
Have him in circles
779 people
Padma D's profile photo
Yanu Gupta's profile photo
Guru Mann's profile photo
akhil ambi's profile photo
Manoj Kumar's profile photo
Young Lee's profile photo
MIND's profile photo
Brian King's profile photo
Dorjee Taku's profile photo
Work
Occupation
software engineer, school teacher, singer, physics enthusiast, shutterbug, nature lover, Indian
Employment
  • Fiserv
    2010 - present
Basic Information
Gender
Male
Looking for
Friends, Networking
Relationship
Single
Story
Tagline
A purist..
Bragging rights
can you twist your tongue 180 both sideways? guess who can.. :P
Places
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Currently
pune
Previously
allahabad - hyderabad - mumbai - delhi - nagpur
Sree Harsha D's +1's are the things they like, agree with, or want to recommend.
Pocket Tanks
market.android.com

"The Ultimate One-on-One Artillery Game" – Now with cross-platform ONLINE Play!Pocket Tanks is the fast-paced artillery game that is simple

CNET 100
www.cnet.com

We built a one-of-its-kind leaderboard that tracks tech's hottest products. Find out what's on top this month.

matthen
blog.matthen.com

Things of interest in Maths & Science

National Constitutions
www.constitution.org

Click on the button to get the indicated file format: Format, HTML, Text, WP, PDF, RTF, Word, Image. Local, HTML Version or Menu, Text Versi

Google Politics & Elections
www.google.co.in

Google Politics & Elections. Your elections hub to study, watch, discuss, participate in and make your impact on the digital campaign trail.

Why Indians love Sachin Tendulkar
www.bbc.co.uk

Author and historian Ramachandra Guha pays tribute to Sachin Tendulkar on his retirement.

WhatsApp Messenger
market.android.com

WhatsApp Messenger is a smartphone messenger available for Android and other smartphones. WhatsApp uses your 3G or WiFi (when available) to

ThisIsWhyImBroke.com
www.thisiswhyimbroke.com

ThisIsWhyImBroke is where you'll find cool, unique, and geeky gift ideas. You'll never give a boring gift again with our never ending list o

List of Indian states and union territories by the etymology of their na...
en.wikipedia.org

State name (# on map below), In State Language, Meaning, Notes. Andhra Pradesh (1), ఆంధ్రప్రదేశ్ (Telugu), South, Andhra denotes "south" in

Be Like Water: The Philosophy and Origin of Bruce Lee’s Famous Metaphor ...
www.brainpickings.org

"In order to control myself I must first accept myself by going with and not against my nature." With his singular blend of physical prow

Belle de Jour (writer) - Wikipedia, the free encyclopedia
en.wikipedia.org

Brooke Magnanti (born 5 November 1975) is a research scientist, blogger, and writer, who, until her identity was revealed in November 2009,

Language - Wikipedia, the free encyclopedia
en.wikipedia.org

Language is the human capacity for acquiring and using complex systems of communication, and a language is any specific example of such a sy

WWE
plus.google.com

The official home of WWE Superstars and Divas on Google+!

The Economist - World News, Politics, Economics, Business & Finance
www.economist.com

Authoritative weekly newspaper focusing on international politics and business news and opinion.

Nexus
plus.google.com

News and notes on the latest hardware from Google.

Google +1 Button - Chrome Web Store
chrome.google.com

+1 and share a web page, anywhere you go on the web.

Wikipedia, the free encyclopedia
en.wikipedia.org

Today's featured article. Chilean battleship Almirante Latorre. Almirante Latorre was a super-dreadnought battleship built for the Chile

The Beginning of the Universe and the Limit of Knowledge
scienceblogs.com

“Despite its name, the big bang theory is not really a theory of a bang at all. It is really only a theory of the aftermath of a bang.” -Ala

What Rhymes With - Rhyme Dictionary
www.whatrhymeswith.com

What rhymes with any word Find rhymes poems articles books, type or scheme syllable vowel and consonant counter. Words sounding or pronounce

Nexus S – The new Android phone from Google
www.google.com

Nexus S is the newest Android phone from Google. With Gingerbread, fast just got faster.

1 review
Map
Map
Map