Psychology - Sensation and Perception, Signal Detection Theory.

Sensation and Perception

The abilities we are born with are most of the time extremely unappreciated and undermined. From the beginning of the chapter, a story revolves around a man who due to trauma lost the ability to differentiate letters, and in result couldn't read; later he also lost the ability to see colors and then lost his drawing skills. The perception that everything is constant is unfortunately too often part of our lives.

Signal Detection Theory

Sensations depend on the character of the stimuli and according to the classical theory it also depends on the background information and the detector. These are transmitted through the eyes, ears, nose, skin among other sense organs. Not out of the ordinary is that in daily life, we do not notice certain details in one situation, whereas in the analogical situation it's probably that they would be left ignored. The classical theory of threshold confirms this, however strangely enough ignores the effects of the individual's physical condition, judgments and biases. Personally, I don't see how accuracy can not be affected by an individual's personal factors. Therefore, I've introduced myself to the signal detection theory, which offers the approach the missing details. Signal detection theory observes the human judgment and recognizes the observer. In result, the variable conditions aid in differentiating the stimulus, and the theory ultimately provides more accurate evaluation than the classical method.

How the Visual System Creates Color

The generic perception of the world being colorful is unfortunately misleading. Color does not exist outside the brain and an explanation for the matter would be that color is simply a sensation the brain creates in the form of a wavelength of light that passes through the eyes. While most of us are blessed with a fully functioning beam of light, based on statistics conducted in Penn State University (Gilmore, R. 2008), up to 8 percent of men globally, and more than 10 million American men suffer from colorblindness. The research also established that although women are more likely to carry the recessive chromosome that leads to colorblindness, for unpredictable reasons men are more likely to inherit the defect. Rick Gilmore, Ph.D., associate professor of psychology explains the defect to occur in the light-receptor cells in the retina, which supports the ability to differentiate colors. Apparently, three kind of cells, also known as cones, exist and each of them work in different ways towards the visible light spectrum. The ability to see in color depends on the way these cones interact, of which each one reacts sensitive to red, green and blue lights respectively. If one of the cones fails to work or in some was becomes damaged, the result will most likely affect