What is the most interesting thing you learned this semester?

After taking this class of Perception, I have gained a tremendous amount of information about our senses and the world around us. I was not aware of how complex this process truly is. We were able to learn deeply about our five senses and the way we use them to perceive the world around us. After performing several mini-day experiments for our papers, I also go an opportunity to truly appreciate the importance of my senses. I remember doing the experiment for our first paper – about realizing the value of the sense of touch. At the end of the day I immediately came upon to the conclusion that touch is one of the earliest and most important senses in our body. With the ability to feel the sensation of touch, we are able to keep in “touch” in with the rest of our environment. The touch receptors in our body send electrical impulses to the brain thorough the nerve fibers. This information is further processed and analyzed in the brain, which then signals the rest of the body. The ability to feel pain, texture, shape or identity of an object is derived from this sense of touch. Without the ability to feel touch, I found myself struggling with simple tasks in life and had to rely on my other senses to get a better understanding of the world around me.  I was obligated to compensate for a poor sense of touch by relying heavily on my other senses. Under normal circumstances, we tend to forget the usage of the sense of touch in everything we do in life. Without this sense, we could possibly lose touch with the environment and the world around us. Even though I was truly intrigued with the importance of this sense of touch, I know that if I could never live without my sense of vision.

According to Professor Boucher, vision is the sense “that we take most for granted, and the one that we miss the most when we suddenly are without a keen sense of sight”. This statement had made a difference in my understanding of the visual world and has definitely convinced me how crucial vision is in our everyday experience. However, more importantly, even though we are able to see things visually, it’s the art of recognizing the objects is what is crucial to our understanding of the world. The concepts and theories behind object and face recognition is definitely one of the most interesting facts that I learned in this class. We recognize objects everyday in our life and we do this with very little effort and conscious. I was definitely amazed by the mechanisms that are involved behind this area of perception.

Several theories are involved behind object recognition. According to our textbook, Biederman proposed the theory of recognition by components in which he explains that when people first look at an object, they create a rough sketch in their head on the basis of the shape of the object. He proposes that the visual system extracts geometric icons or geons (picture above) and that is how we identify objects. His theory depicts two important properties – he claims that geons can potentially be distinguished from one another from any viewing perspective. The representations of objects are stored in the brain as structural depictions. He also states that when even when the random parts are erased from the geon, the rest will almost always remain recognizable. However, this theory was only accountable for the primal recognition of the objects because a higher level processing would involve more information about the objects including the spatial recognition, size, color, texture, and position of the object relative to its surroundings.

So what happens when we see an object again? How are we able to recognize the same object over and over? The neurons in the region of the IT cortex participate in recognition of objects and faces. The neurons in this area exhibit complex selectivity and some only respond to specific objects. Blake explains how IT neurons have large receptive fields, which means that the neurons will respond to an object that appears anywhere within a large region of the visual field. What I thought was most interesting in this area of research was also the ability to recognize faces. Of all the objects we are able to recognize in our everyday life, we are forced to look at thousands of faces be able to recognize them. A theory that explains this effect is the face inversion theory. Face processing is also referred to as holistic processing, the processing of information beyond the individual parts of the object, which means that faces are processed as a whole rather than in individual parts. According to Blake, in the textbook, we are able to process faces as global configurations, which leads us to be unable to just attend to one part of the face. In the above figure, it is more difficult to recognize faces when the contrast has been reversed as this distortion in contrast disrupts the facial cues we use to recognize faces. In class, we also learned about the six basic types of emotions found in all ages and cultures including sadness, happiness, anger, fear, surprise and disgust. We also learned about how an angry face stands out in a crowd of angry faces. I thought this was quite interesting and possibly true from an evolutionary point of view. The book also states the same reasoning, as it is probably important to recognize a potential enemy among friends than it is to detect a friend among a group of enemies.

After learning the various concepts of perception and our five senses in the class, I am much more aware of the complex processes involved in our everyday life. I was truly intrigued by the process of object recognition and face recognition. This has truly changed by perspective on the importance of our senses because even though vision is one sense that we definitely take for granted in our everyday lives, we also take the idea of this concept for granted. We would not be able to function without this processing; as even if we could see objects with our vision, not being able to recognize the various objects or faces would cut us off from the aspects of life.