Perception

People appear limited to the number of things in which they can simultaneously attend and perceive because we can only know so much and can work for only so long. We are not machines, unlike a robot or mathematical equation, the human mind can only configure and perform actions for an X amount of time, before needing to eat or rest. As you know, each person has his or her own perception of the world and their culture they live in. Psychologists have had a hard time grasping and explaining a concept like this, because they can identify the symptoms to a problem, but cannot always solve it; they are good, because they are already half way to the answer. Doctors and psychologists have been studying and researching this since at least the 1960's. We can only attend to one thing at a time, and perceive the things we attend to. Psychologists have tried to explain this by describing situations or theories where attention and perception are limited.

Attention is the stimuli in which you take in, while perception is how you make sense of it or how you view it. This concept has to do with seeing what’s in front of oneself and understanding it. Attention is controllable, restricted and selected. There are many different theories of attention. For example, Broadbent’s Filter Theory explains how selective attention operates. It contains two systems: the sensory system and the perceptual system. The sensory system receives the information through ones organs, such as ones’ eyes, while the perceptual system process the information from the sensory system. Our senses encode the information our brains perceive. Basically, the unattended messages are filtered out, and one channel for attention is selected. In a study done by Broadbent to see how people were able to focus their attention, he overloaded them with stimuli, known as the dichotic listening task, which is when a participant listens to two different phrases at once and repeats what they heard (McLeod 2008a). Broadbent established that we pay attention to only one channel at a time because we have a limited capacity to process information (McLeod 2008a). His filter is designed to prevent the information-processing system from becoming overloaded (McLeod 2008a).

While Broadbent’s Filter Theory has some important points, it has been criticized because other findings indicate that there are separate short-term and long-term memory systems occupying different areas within the brain (Baum). “Eysenck and Keane (1990) claim that the inability of naïve participants to shadow successfully due to their unfamiliarity with the shadowing task rather than an inability of the attentional system (McLeod 2008a).” If the learning task involves data-driven processing, then performance will be better when the memory task involves data-driven processing and similarity for conceptually driven learning tasks. Participants also noted that after the message had been played it was possible that the unattended message was analysed thoroughly but participants still forgot (McLeod 2008a). Treisman’s Attenuation Model incapacitates some of the problems with Broadbent’s Filter theory. One of the main differences is that Treisman’s filter attenuates rather than eliminates the unattended material; his model explains that the processes have never been accurately specified (McLeod 2008a). The findings are limited because all dichotic listening experiments can never be sure that the selected participants have not actually focused attention to the unattended channel. We can only fully perceive what’s going on and what we’re doing in that moment.

Following this, multi-tasking is a major limitation because focusing on multiple things at once causes the brain to lose sight on what is actually important, since the attention is limited. The issue is selective attention, because the mind perceives only what is currently relevant (Schacter). Such as, trying to drive while talking on a mobile phone. This enquires balancing two independent sources of sensory input at the same time: vision and audition (Schacter). Research shows that experienced drivers react slower during phone conversations because conversations require memory retrieval, which slows the mind down (Schacter). Regardless of if it is a hands-free device, the thought process of carrying out a conversation, getting taken away with it, and focusing on driving, can be a dangerous thing and can cause the mind to lose sight on what is actually important. Although multitasking can be beneficial at times, it can cause more errors due to inadequate attention.

Along with attention, perception is another key factor. Perception is a conscious awareness. Gibson’s Theory of perception argues that perception is direct and what you see is what you get, or seen with little processing (Bennett). Vision happens instantly and is generally accurate. It is an automatic natural process. He claims that perception is a bottom-up process, where sensory information is evaluated by raw sensory data of the visual system (McLeod 2008b). Perception starts by evaluating the basic features of the sensory input and then works its way up to more involved processing. His optic flow theory explains that the apparent motion of matter is caused by the motion between the environment and the observer. Some neurons in the visual cortex do respond to optic flow patterns (Bennett). Gibson’s theory describes the quick and accurate perception on the direct way in which we view the environment (McLeod 2008b). His theory provides an accurate perception of the environment, but fails to explain why things such as illusions appear to be inaccurate (McLeod 2008b). If perception is direct, people should not be prone to visual illusions. Gibson’s evidence in his findings have been interpreted in ways which are simple to understand, such as his optic flow theory, but are limited in ways where flaws appear in his theory, such as the view of illusions.

Gregory’s theory of perception is a ‘top down’ theory that contradicts Gibson’s theory. He sees perception as a hypothesis. We construct our perception keenly based upon what we are seeing, and when the sensory input is unusual, we guess what we are seeing, also known as hypothesis-testing (Bennett). One of the limitations or weaknesses in Gregory’s theory is that if visual perception does involve hypothesis-testing, people would make more mistakes than they actually do. The formation of incorrect hypotheses will lead to errors of perception (McLeod 2008b). The findings have been interpreted in ways that explain how the information reaches the eye, but that much is lost by the time it reaches the brain (Gregory estimates about 90% is lost); this leads the rest to be hypothesized, usually based on past experiences (McLeod 2008b). Gregory’s theory of perception is beneficial in certain ways, but still consists of flaws.

All theories have flaws. Nothing is ever perfect or how it seems. They all have strengths and weaknesses. Theories appear to be limited in certain ways because the entire theory cannot prove to be accurate in every situation, such as the Filter theory. Everybody is different and is going to focus their attention to a certain channel that could be different than the participant before. This theory has many flaws because no matter how many times the experiment is done, the channel the participant chooses to hear can vary. Theories still provide accurate information that explain the overall concept of what is being achieved, but contain flaws in the conclusion.

Perceptual and attentional limitations are related in these theories and nothing can ever be 100% accurate. The way one perceives the world will always be different than the way another person does. It will never be totally accurate because everyone’s mind processes information in different ways. There is no right or wrong way to how we perceive things, or what we choose to focus our attention on. Our brains don't process information in the same way as someone else's thus none of these theories can be 100% accurate. "The eye sees only what the mind is prepared to comprehend." -Bergson

References:

Baum, A., (1990) Cambridge Handbook of Psychology, Health and Medicine.

Cambridge: Cambridge University Pr

Bennett, M. R., Farnell, L, Gibson W.G., (2008). Journal of Theoretical Biology, volume 252 (1), 123-130.

Mcleod, S. A., (2008a). Selective Attention. [Online]. Available from: http://www.simplypsychology.org/attention-models.html [March 2nd 2013].

Mcleod, S. A., (2008a). Selective Attention. [Online]. Available from: http://www.simplypsychology.org/perception-theories.html [February 19th 2013].

Schacter, D., (2012). Psychology: European Edition. Hampshire, UK: Palgrave Macmillan.

[Online]. Available from: http://blackboard.lsbu.ac.uk [February 21st 2013].