Question - Violet Claim - Red Evidence - Blue Assumption - Green Constraint - Yellow
It is generally agreed that sensory experience depends on selective attention.
To select and attend to one thing, it must be perceptible to our sense organs. It also must be sufficiently defined to stand out from its background.
A single object may be experienced via different senses. We see a man playing the violin, hear the sound, can touch the violin and feel its vibrations. We know without any process of reasoning that the sound comes from the man playing the violin.
Individual senses cannot convey such integrated experience. All the sense of sight can do is mediate visual experience; the sense of hearing, auditory experience. Yet we see things, not patches of color, hear melodies, not single tones following one another. We touch an object and form a notion of its shape, rather than having discrete touch sensations. Sensory experience is integrated before we become aware of it. Such an integration of experience must be some kind of sensory function because it is unperceived, preattentive, as direct as all sensory experience.
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Claim : Sensory experience depends on selective attention
Assumption : To attend and object it must be a percivable and must stand out.
Claim : Integration of senses are necessary for perception. Integration is direct, unpercieved and preattentive.
Claim : Individual senses cannot convey integrated experience
Evidence : by observation of sound comes from the man playing the violin.
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The infant's world has as yet no meaning, that the infant sees things but does not know what they will do to him or how he can cope with them. For such knowledge, he has to touch and manipulate them and find out how they will affect him. The memory of such experiences will then gradually make the world meaningful to him.
The integration and articulation of the environment into separate objects must necessarily occur before we experience anything. It must be a sensory function, completing the experience of seeing, hearing, touching; we could call it the function of an integrative sense, mediated, like sensory experience, by the cerebral cortex.
To imagine things in some side-by-side order, we need a visual memory schema. If it is missing, visual imagination cannot organize visual memory images.
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Claim : The stimulus recieved from various senses must be associated and integrated for making meaningful perception of an object or environment. Not only that they must also be articulated (seperately conceptualized in parts) before we percieve.
Claim : To imagine things in some side-by-side order, we need a visual memory schema. If it is missing, visual imagination cannot organize visual memory images.
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Our notion of visual space implies that there is a certain order among the things that surround us, that they are spread out before our eyes.
VISUAL SPACE
Not every sensory modality can give us a precise notion of the location of things around us. We know that something we touch is close at hand, but we do not know exactly how far something is that we see or hear. But various cues (relative size, relative clearness, etc.) allow us to learn how to estimate distance more accurately. We innately perceive things ordered side-by-side and in depth; but the accurate perception of distance demands experience and memory.
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Claim : Location and placement of an object and the estimation of distance there from requires various cues from different sensory organs.
Claim : accurate perception of distance demands experience and memory.
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When a man lacks sight, it is much more difficult for him to achieve a correct notion of the direction and distance of things in relation to himself, but it is possible with the help of movement and touch. People born blind are able to find their way around the house, around the neighborhood, and even around their district, with remarkable confidence. This surely means that they have formed a notion of the way things are arranged around them. They must have a map of their environment so that they can use spatial concepts without difficulty. Of course, their space is not a picture of things spread out around them but a structure of objects in various directions and at various distances from themselves, measured by the time it takes to walk to them.
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Claim : To move around in a locality we require to have a Map of the environment so that we can use spatial concepts without difficulty. It is in form of a structure of objects in various directions and at various distances from themselves, measured by the time it takes to walk to them.
Evidence is in blue
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for instance, that such patients (blind presons who regained their sight) did not recognize simple objects on seeing them. They could distinguish a circle from a square but could not say which was a circle and which a square. But when they traced the outline of both, they immediately knew their name, and ever after could recognize these two figures, no matter what size or color they were, or of what material they were made. Apparently, when blind, the patients had learned to recognize circle and square on the basis of tactual and particularly motor memory. Since the shape traced manually and so registered and remembered as a motor memory image had no connection with any visual memory image, merely seeing the two figures did not suggest the outlines the patients had traced and remembered. Once they had both seen and traced the two figures, and so connected the two experiences, they were able to recognize circle and square on seeing them.
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Claim : To develop perception people need to connect their various sensations / sinals received from different sources then store them and then connect the stored sensations and images to develop different concepts.
Evidence : Since the shape traced manually and so registered and remembered as a motor memory image had no connection with any visual memory image, merely seeing the two figures did not suggest the outlines the patients had traced and remembered
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CONSCIOUSNESS, MEMORY AND PERCEPTION
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Claim : Every perceptual experience presupposes awareness; and awareness is impossible without memory
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Every perceptual experience presupposes awareness; and awareness is impossible without memory. Our awareness includes not only the present moment but a stretch of time immediately before, what William James called the "specious present." To be conscious means that we are aware of what goes on around us, that we sense, think, feel, can move and talk, that we can remember our immediate as well as our distant past, and reflect on our experiences.
Accordingly, unconscious in its simplest sense means the absence of the activities of knowing, wanting, doing, remembering, and reflecting. A disturbance of consciousness is an interference with these activities, or their temporary loss.
Of course, some of these activities may not be observable. A person may not be able to move or to talk, yet he may be fully aware of what goes on around him. But to be conscious at all, he must be able to perceive and evaluate what he perceives. To be fully conscious, he must be aware of the external world and of his own experience, present and past, and must be able to use what he knows. Consciousness, like memory, has been a step-child of psychological science during the last few decades. But unlike memory, it has not as yet made a comeback. Early in this century, when psychology had barely been accepted as an experimental science, Watson had insisted that consciousness is not a fit object for scientific research; that science has to restrict itself to the investigation of phenomena accessible to public observation and measurement. Whatever the methodological reasons for such an ostrich policy, psychologists have followed it for many a long year. This neglect of consciousness has impoverished experimental psychology and has deprived clinical psychology and psychiatry of help in an area crucial for understanding mental disorders as well as the effects of brain injury. Only recently, with the advent of cognitive psychology, have theorists come to realize that there is an important gap in their scientific domain. As Norman ( 1979) says: "the phenomenon of consciousness is so fundamental to our mental lives that it seems strange that experimental psychologists have ignored it so conclusively." (p. 142.) While the functioning of at least some afferent sensory pathways is necessary for consciousness, the normal functioning of the sensory system is not sufficient. Experimental subjects may not even "see" a word presented tachistoscopically when it is "masked" by an inappropriate word that follows immediately afterward. According to Allport ( 1979), conscious awareness depends on a preattentive processing of visual impressions. An unconscious patient may receive sensory impressions (as shown by electrical potentials recorded from the sensory cortex) yet be unable to react to them in any way. In contrast, a person may move and even speak, yet be unable to reflect on what he is doing or remember his actions afterwards -- for instance, in "temporal automatisms" ( Penfield, 1952).
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Claim : But to be conscious at all, he must be able to perceive and evaluate what he perceives. To be fully conscious, he must be aware of the external world and of his own experience, present and past, and must be able to use what he knows.
Claim : Cosciousness is necessary for perception
Evidence : An unconscious patient may receive sensory impressions (as shown by electrical potentials recorded from the sensory cortex) yet be unable to react to them in any way.
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Full consciousness necessarily includes a person's ability to remember what is happening or what he is doing, and also to remember who he is, where he is, and what he is about to do. So-called "clouding of consciousness" is characterized by confusion: The patient does not know where he is, what year or season it is, or who are the people around him. Although this state has been defined differently by different psychiatrists, there is agreement on the main symptoms. The patient is confused, incoherent, inattentive, misidentifies things and people; in short, is unable to grasp the real situation.
It seems clear that brain function has been disturbed in such cases and has brought about an interference with the spontaneous continuous recall needed for remembering what is happening and what we are doing in our daily life. Delirium, brain damage, electroshock, and concussion, represent such an obvious interference with normal brain function that we may well ask ourselves whether psychosis might not also have the same effect
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Claim : To be conscious a person need to be able to remember
Evidence : In cases where brain functions are disturbed there develops some interference in the process of contenuous recall needed for remembering what has been happening in and what we are doing in our daily life.
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When we try to identify the processes used in perception, we find that we must be aware of a situation, attend to it, and identify it by recalling similar situations. Often, when memory fails, we imagine what must have happened to fill the gaps. We can recall and imagine something seen or heard, even smelled, tasted or touched. We may need the help of visual images to form a memory image of what it feels like to touch velvet, what a good steak tastes like, or to re-experience the fragrance of a rose. Still, these memories are not pure visual images; they are also touch, taste, and olfactory images. We could call this type of recall modality-specific memory.
In addition, we evaluate perceptual experiences. We appraise the situation as good or bad for us, as beneficial or harmful, to be approached or avoided. This appraisal also draws upon memory, both on the recall of specific similar instances, but also on past appraisals. What we have found pleasant in the past, we will find pleasant when we meet something similar. We could call this immediate positive or negative reaction to something affective memory. This type of memory is immediate, spontaneous, and non-deliberate, while modality-specific memory may be recalled spontaneously or deliberately. Ordinarily, affective memory accompanies modality-specific recall. But it may happen that we instantly (we often say, "instinctively") like or dislike something or someone without any conscious memory of having had such an encounter before.
we have no habitual way of dealing with the situation, we make a guess what to expect from it. This requires imagining possible situations and possible ways of dealing with them. The choice of what we judge the best alternative leads to a particular response.
Since perception involves different activities in a specific sequence, we have to look for structures and pathways that mediate each of these activities, one after the other, rather than looking for particular "memory centers."
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Summary
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