The Relationship between the Eyes and Energy?

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Discussion Overview

The discussion revolves around the relationship between the eyes and energy, specifically focusing on whether energy enters and leaves the eyes during the process of vision. Participants explore concepts related to light as energy, its behavior, and its interaction with the eyes, touching on both theoretical and practical aspects.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions the claim from a psychology textbook that energy only enters the eyes, proposing that energy both enters and exits the eyes due to the nature of light.
  • Another participant agrees that energy in the form of light both enters and leaves the eye, citing the red-eye phenomenon as an example of light reflecting off the retina.
  • It is mentioned that all objects, including the eyes, emit thermal electromagnetic radiation, indicating that the eyes lose energy to their environment.
  • A participant expresses the need for scientific articles to support the claim that light energy both enters and leaves the eye, particularly for academic purposes.
  • One participant suggests that the concept is too basic to require an article, comparing it to asking for proof that water is wet.
  • Another participant provides examples of reflective surfaces in animal eyes that demonstrate light reflecting back out, such as in deer, and mentions the practical implications for optometrists examining eyes.
  • Several links to scientific articles are shared as potential resources to support the claim about light reflection and absorption in the eyes.

Areas of Agreement / Disagreement

Participants generally agree that energy in the form of light both enters and leaves the eyes, but there is some contention regarding the need for formal proof and the authority of the psychology textbook referenced. The discussion remains somewhat unresolved regarding the necessity of scientific articles to validate basic concepts.

Contextual Notes

Some participants express uncertainty about the claims made in the psychology textbook and the implications of those claims in the context of physics. The discussion highlights the complexity of light behavior and its interaction with biological systems, but does not resolve the need for further evidence.

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Recently, I was reading through a psychology textbook (Introduction to Psychology, James W. Kalat, 7th edition) and it mentions that when we see something using our eyes, energy goes into our eyes and energy does not come out of our eyes. Is this true?

Based on what I know, light is a form of energy, it can behave like a particle at times, and like a wave at other times as well. When light hits an object, that it can be absorbed, reflected, transmitted, refracted or a combination of the four. Based on that, I think that energy not only comes into the eyes but also out of our eyes. When we see something, some of the light is transmitted into the eye and some is reflected (energy goes out) from the eye. As a result light (energy) is going into and out of our eyes simultaneously. In addition to that, the angle of which the light hits our eyes also affect whether the energy enters or leaves. Besides that light that enter our eyes can be scattered due to the surface of our pupil, so if the surface is not efficiently correct, light will scattered, with some transmitted into our eyes and some reflected away.

I have not found any specific scientific journal articles that describe the relationship between light energy and the eyes. Please direct me to any resources that can help me understand the relationship between the eyes and energy. Thank you very much for your time,:smile:
 
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Please do not double-post.

You are correct that energy (in the form of light) both enters and leaves the eye.

There is no such thing as a perfect absorber of radiation in the real world, though physicists often consider theoretically perfect absorbers (called blackbodies).

The red-eye phenomenon that ruins photographs is caused by the retina reflecting some of the energy emitted by the camera's flash.

Also, I should note that all objects produce thermal electromagnetic radiation with wavelengths corresponding to their temperatures. Our eyes, at about 300 kelvin, are constantly radiating in the infrared spectrum, losing energy to the (presumably cooler) room-temperature environment. The rest of our bodies radiate the same way.

- Warren
 
Thank you for your help. Do you know of any scientific article that support the fact that light energy both enters and leaves the eye?
 
Honestly, I'd say it's too basic a concept to warrant an article. It's like asking if I can point you to an article proving that water's wet.

If all you're trying to do is disprove your psychology book, you're already done. However, it's a psychology textbook, and probably shouldn't be considered authoritative on physics anyway.

- Warren
 
The reason that I need an article is because I need to prove to my teacher that my answer on my mc test is correct. I have talked to her about why I said energy comes in and out of the eyes but she wants further proof.
 
How about this:

image of the illuminated retina is again focused by the lens of the eye back to the camera

You're effectively taking a picture of the back of the eye, which obviously involves light both entering and leaving the eye.

http://en.wikipedia.org/wiki/Red-eye_effect

- Warren
 
*sigh* I don't know what's in the Introduction to Psychology text, but Kalat also has a Biological Psychology text that makes no such claim (of course my edition is rather old).

If your teacher needs evidence that light also escapes back out of the eye, point out the phenomenon of animals having "glowing" eyes at night, in particular ruminants, such as deer. They have a reflective surface in the back of the eye that helps enhance their night vision, but also reflects light back out even more noticeably so that their eyes appear to glow if you shine a light at them at night.

Also, if light shined into the eye was completely absorbed, optometrists would not be able to see anything when they examined your eyes...you can shine a light in and what reflects back out helps the doctor see the retina during an eye exam.

Actually, here, try these:
http://www.ncbi.nlm.nih.gov/entrez/...uids=15820514&query_hl=22&itool=pubmed_docsum

http://www.ncbi.nlm.nih.gov/entrez/..._uids=8776488&query_hl=22&itool=pubmed_DocSum

http://www.ncbi.nlm.nih.gov/entrez/..._uids=2375701&query_hl=22&itool=pubmed_DocSum

http://www.ncbi.nlm.nih.gov/entrez/..._uids=7260483&query_hl=22&itool=pubmed_DocSum

http://www.ncbi.nlm.nih.gov/entrez/...t_uids=409694&query_hl=22&itool=pubmed_DocSum

These are just the abstracts (brief summaries) of the complete articles, but it should be enough to satisfy your teacher. The last one is straight to the point...reflection is precisely what they were measuring.
 
Last edited:
Thank you very much for all your help
 

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