In some cases, automatic top-down processing of stimuli even seems obligatory. J. R. Stroop (1935) first demonstrated the obligatory nature of reading. In the study, subjects were presented with a list of words of various colors: red, green, blue, brown, and purple. The words were presented in color so that each word was not printed in its representative color; that is, the word “red” could appear in blue ink, or the word “brown” in green ink. The subjects were then asked to relay the color of the ink that the word was printed in rather than the word itself. The results indicated that, compared to when word color was matched with the typed color, those who were presented with conflicting stimuli had slower relay times when naming the colors. This phenomena is explained by the concept of interference, in that related stimuli that are presented simultaneously will interfere with one another. In this case the unconscious processing of the words accounts for the interference; although one is focusing attention on determining the color of the word, the unconscious recognition of the word is presented to consciousness and the relationship between the two stimuli distract the focus of attention. Thus, these top-down attention events effect conscious perception of stimuli.
All of the aforementioned literature focuses on visual stimuli. However, this is not the only important stimulus when studying attention systems. Like memory systems, different sensory stimuli may have separate but interconnected attention systems that effect consciousness. The following proposed study focuses on the attention system of tactile stimulation. Literature on tactile attention is more limited than visual and auditory stimuli because of the ease of manipulat...
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... Journal of Experimental Psychology, 32, 3-25.
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Stroop, J. R. (1935). Studies of interference in serial verbal reactions. Journal of Experimental Psychology, 18(6), 643-662. doi:http://dx.doi.org/10.1037/h0054651
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Anne Louise Oaklander then proceeds to discuss touch. She explains that senses have evolved specialized organs to process senses that were already discussed in this forum. Touch however, as Oaklander explains, can be perceived all throughout the body- something she likes to refer to as “somatosensation.” Oaklander defines somatosensation as: “A product of a number of different kind of sensory processes all chiming in to give you a perception.” All these sensory processes are somehow connected with processes in the brain.
Although correlation does not equal causation, we can conclude that similar cognitive processes, such as interference and automaticity, have influenced the results in our experiment. This can be expressed by the data and in identifying and saying aloud/reading a simple number compared to quantifying simple numbers. The cognitive load of reading familiar or smaller words is lower than that of counting, thus creating perchance a longer reaction time. In the experiment conducted in class as well as the one conducted by Stroop, the issue of divided attention may have been a great factor in interference or prolonged reaction time in the conditions. Psychological refractory period which states that the response to a second stimulus is slowed down by the first stimulus being processed; this can be a cause for the finding of increased reaction time when conflicting information is given. Attention may unconsciously be given to the less complex task, which is reading/identifying, and counting the main and more complex task may be interfered by the simpler stimulus. The expectation of having a longer reaction time when conducting the incongruent task was referenced back to the Stroop effect due to the similar implications of identifying and saying aloud the color presented in the print of the color descriptive word (Stroop,
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It is often thought that humans can receive all the information that invades their senses, however, it is fact they are not able to process all of the received information. Humans must selectively choose what information to perceive and ignore irrelevant information. Two questions are raised, therefore: what allows us to selectively attend information and what happens to unattended information, is it proceeded to any extend or not proceeded at all? Recently, the phenomenon of negative-priming started to be used to study selective attention.
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A recent neurobiological approach to understanding consciousness, at least on a perceptual level, has involved the study of the phenomenon of blindsight. Damage to areas of the visual cortex often result in complete or partial blindness. Although the eye itself is undamaged, patients report an inability to detect any light input in part of (or the entire) visual field. However, experiments regularly show that somehow, visual cues are processed. Visual inputs presented to the blind field affect the patient's response to stimulus in the normal visual field. Reaction times to stimuli are affected as well as the interpretation of the stimuli. A visual cues presented in the blind field may suggest a certain interpretation of an ambiguous stimuli. For example, the interpretation of the word "bank", presented as an auditory cue, differs depending on whether the word "river" or "money" is presented to the blind field, even though the patient does not...
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Macleod and Mathews (1991) induced attentional biases within a laboratory setting to determine that a ca...
Subliminal or unconscious perception refers to the idea that stimuli presented below the threshold for conscious awareness can influence an individual's thoughts, feelings, or actions (2). The possibility that an individual can acquire and act on input without being aware of doing so has implications for the study of consciousness and the larger set of processes which characterize the I-function. It is generally assumed that that conscious perception of a stimulus is necessary in order to act on that stimulus, and this conscious decision to act is one of several processes which characterize the I-function.
The way that our brain processes information and responds to the awareness of things is a very complex system with in the brain. One study mentioned talks about the integration of senses in the brain and how we process the information. “Another study better illustrates the integrative nature of this synchrony. Words were presented in various locations on a screen; whether the subject became aware of the word’s color or if its location-indicated by being able to recall is later-depended on whether a frontal or temporal area was activated during the presentation. But if the individual registered both the color and the location, additional activity occurred in a part of the parietal cortex (Uncapher, Otten, & Rugg, 2006).” (Garrett, pg.501) This research demonstrates how different people react differently to stimuli and different levels of their cognition and awareness. It is important for people to develop a sense of awareness in order to function fully in the world. The book argues “that one apparent advantage is that it enables consistency and a playfulness in our behavior that would not be possible otherwise. (Garrett, pg. 502) It is human nature to rely on a consistency and the ability to plan ahead which is why the function of awareness is so important to the human
Keil, F. C. and Wilson, R. A. (1999) The MIT Encyclopedia of the Cognitive Sciences. Cambridge, Massachusetts & London, England: The MIT Press
With each of our senses (sight, smell, touch, taste, and hear), information is transmitted to the brain. Psychologists find it problematic to explain the processes in which the physical energy that is received by the sense organs can form the foundation of perceptual experience. Perception is not a direct mirroring of stimulus, but a compound messy pattern dependent on the simultaneous activity of neurons. Sensory inputs are somehow converted into perceptions of laptops, music, flowers, food, and cars; into sights, sounds, smells, taste ...
D. W. Hamlyn - author. Publisher: Routledge & Kegan Paul. Place of Publication: Sensation and Perception: A History of the Philosophy of Perception. Contributors: London. Publication Year: 1961. Page Number: iii.
“Consciousness is defined as everything of which we are aware at any given time - our thoughts, feelings, sensations, and perceptions of the external environment. Physiological researchers have returned to the study of consciousness, in examining physiological rhythms, sleep, and altered states of consciousness (changes in awareness produced by sleep, meditation, hypnosis, and drugs)” (Wood, 2011, 169). There are five levels of consciousness; Conscious (sensing, perceiving, and choosing), Preconscious (memories that we can access), Unconscious ( memories that we can not access), Non-conscious ( bodily functions without sensation), and Subconscious ( “inner child,” self image formed in early childhood).
McClelland, J. L., & Rumelhart, D. E. (1981). An interactive activation model of context effects in letter perception: I. An account of basic findings. Psychological review, 88(5), 375.