What actually happens is that the information from the eyes is directed to a form of processing centre in the brain where it is added to information from our other senses and memories of our past experiences. Once all this information has been assembled our brain jumps to a conclusion as to what it is we are looking at.
It therefore stands to reason that factors such as our mood, tiredness or health might affect our ability to process all this information. In fact, this is the conclusion of researchers at the University of Toronto who have found that our mood can affect our sight.
Their findings, which were published in the Journal of Neuroscience, were that people in a positive mood saw while those who were more down in the dumps suffered from tunnel vision. While being cheerful is generally seen as a good thing, Taylor Schmitz, one of the researchers, commented; “this can lead to distractions on critical tasks that require narrow focus, such as operating dangerous machinery or airport screening of baggage.”
The conclusion therefore seems to be that if you need to do something that requires you to focus your vision in a concentrated way; rose tinted spectacles can be dangerous!