Top down and bottom up processing refer to two different theories regarding how the brain processes information delivered via the senses. The former refers to the idea that the brain takes in the information as a whole and breaks it down to the tiniest, most minor aspects of itself. The latter refers to the idea that it all begins with individual elements that are taken in, one by one, and pieced together to get the entire structure as it truly is. Although it may not seem like there is much of a difference between the two, there actually is. Sensation and perception are complicated concepts that still have many unanswered questions surrounding them, such as those addressed in feature integration theory, which asks how exactly is information pieced together in a structure – is it just all one thing or is each individual aspect analyzed separately and the brain constructs it all together in the final product like that of a puzzle being assembled.

Regarding the actual processing itself, it all goes back to our senses. Years ago when I was a student at my former college, the University of Pittsburgh, and I took a class called Sensation and Perception, I realized that we don’t “see” through our eyes. What we actually “see” is our brain’s replication of what is before our eyes, via the use of electrical signals made from light after its transduction along our optical nerve. Likewise with our other senses such as auditory, it is our brain’s replication of a specific motion of sound waves. Top down processing and bottom up processing are two different arguments pertaining to how exactly this manner of information interpretation via our brain’s is done. Is it done from bottom to top, or top to bottom?

An example in my own life when I think of these processing methods is that of when one is approaching an object from afar and as the vision becomes clearer overall as ones nears said object, the details become more and more certain until one is close enough to see it in entirety and all of its details are clear as can be and one is fully aware of what is being viewed. This example of features being integrated from bottom up.

Wede, J. (2017) Lesson 4: Bottom Up Porcessing. Retrieved from Lecture Notes Online Web site:

Wede, J. (2017) Lesson 4: Top Down Processing. Retrieved from Lecture Notes Online Web site:

Goldstein, B. Sensation and Perception. 1980.

Feature Integration Theory is a confusing and important theory often studied in modern psychology. It aims to answer the question of how exactly humans, as well as other organisms, integrate the features of things in the visual field in the grand perception of an object. The question is often asked whether or not the entirety of the object is placed together as a single subject or if it is individually placed together as one via the various features such as size, color, texture, etc.?

In terms of biology, different areas of the brain are specialized to process different things. Such is that of  vision, which is processed inside the occipital lobe, and human faces even have an area designated to their processing inside the temporal lobe. Interestingly enough, a part of the brain exists that is specifically designated with direction in terms of physical space and navigating the area to and from. Feature integration theory aims to discover just how exactly it is that the physical brain does this and how each individual piece is combined together, forming a single picture, which we perceive. Although it is a bit alarming, humans and all animals technically do not see through their eyes. Our visual perception is truly a replication of what is in front of us. Our brain is able to use color (which we perceive) for the sake of identifying light by its wavelength. All of this is how the brain is able to do such, but the exact mechanics are still not entirely understood.

Specialized neurons fire in the presence of light. Cells called cones and rods that rest upon upon the retina at our eyes’ back most wall fire in correspondence to the particular wavelength detected. Color is our mind’s manner of distinguishing different wavelengths form others after the light is transducted into chemical signals via the optical nerv, which is then expedited towards the visual cortex. Cones, which are specifically meant for brighter environments, have at least three different types and each of them correspond to either green, red, or blue color, respectively. Studies conducted via imaging techniques in laboratories have found that thirty two areas (at least) of the brain activate as this processing of the visual stimuli occurs once the light is transducted. This observation supports Feature Integration Theory’s belief that each individual aspect of an object is separately pieced together.

Treisman is the researcher who developed this theory. The experiment he performed to prove his point involving showing to numerous participants a picture that had four objects concealed via two numbers of black color. He flashed the portrayal for less than a second and proceeded via showing them a random dot masking field upon the screen for the sake of eradicating any and all “residual perception that might remain after the stimuli were turned off,” as he worded it. The instructions were for the participants to report which black numbers observed at each location where the shapes were prior seen. Treisman’s hypothesis was verified for it was found that during 18 percent of the time, the participants claimed to see shapes “made up of a combination of features from two different stimuli,” as Treisman worded it, and this was found true for the participants even as the stimuli had varied differences. This was dubbed “illusory conjunction” and is found to occur in real life scenarios at specific occasions. Feature Integration Theory justifies illusory conjunctions due to the fact that all features exist independently of one another as the early processing goes on and that if they are not apart of a specific object, the brain can make the error of falsely piecing them together.

In conclusion, the purpose of feature integration theory is that our brains somehow place together individual aspects of objects before our eyes. creating a single picture, which we perceive.

References:

Wede, J. (2017) Lesson 4: Feature Integration theory. Retrieved from Lecture Notes Online Web site:

Goldstein, B. Sensation and Perception. 1980.