Human Spiritual Structure: Perception
Notes in progress © 1998-2002 Alan McAllister  

[Spiritual Structure Home] [Whole Being Explorations
Host Site
[Subscribe Here]

Physcial Perception

Waves carried by the five factors of the physical universe are able to resonate with the five sensory organs (jnanendriyas), the eyes, ears, nose, tongue, and skin. Here they excite nerves or other physical mechanisms which transmit signals to the brain, and there stimulate waves in the citta. When these waves are `seen' by the aham perception takes place.

It is at the seat in the brain that the vibrations enter the citta, depending on the filters in place due to past experiences and samskaras. These filters are intimately linked to the current sense of the conscious self. The seats of the sense organs in the brain can also be activated by the mind itself, without direct external input, as in a dreaming or visualizing experience.

There is a `psychic organ' called the pranendriya, the collective name of the ten vayus or vital airs which flow through the body. This organ categorizes and analyzes incoming waves, making judgments such as `hard' or `soft'. This is performed by comparison with stored experiences (I&I). [This surely also involves the citta? ] Physically one might expect the judgement functions to occur during conscious perception in the cortex. But this would involve the aham as well? How close is judging something to be `hard' or `soft' to judging it to be `pleasurable or `painful', i.e. the comparison with existing samskaric vibrations etc.? Aham and manomaya kosa?

Waves flow in the pranendriya in a pulsative manor, expansion and contraction, and in the pauses in these waves the citta takes the form of the tanmatras. The expansion and contraction of the pranendriya is related to the inhalation and exhalation of the breath. During both inhalation and exhalation the pranendriya is expanding, while during the pauses between these two it can contract. When the pranendriya is expanding the nerves and the citta are also expanding and cannot pass or receive incoming waves properly. This only occurs in the pauses, when the pranendriya is contracting.

This explains the relationship between controlled rhythmic breathing and increased concentration.

In I&I there is a discussion of the limitations of the pranendriya to convey multiple sensations to the citta at the same time.

The pranendriya is also said to be involved with valuations of other persons, that they are kind or unkind, based on `subjective feeling'. Is this related to psychic resonance or dissonance? Or perhaps to a direct perception of the EM field of another person?

Are the filters in place within the citta, or between the citta and the aham? The fact the much more can be recalled under hypnosis than was consciously perceived at the time suggests that the filters are between the citta and the aham, yet the RAS filters before the signals are sent to the organs seats in the brain?

It is said that the attention of the ego (aham) can be lacking and thus perception does not occur. This suggests that the filters are at the level of the aham. How does this match the apparent RAS filtering on the physical level?

In some persons with brain injuries, or mental problems, the awareness of the senses is affected, in particular the senses of touch, pain, and body location. One case is reported in which these were restored when coupled with sight or sound. [SFF]

Visual Perception

There are three types of receptors (cones) in the eye, tuned for red (long wavelength), green (medium wavelength), and blue (long wavelength). These receptors are interconnected, and can feedback to each other, starting in the eye itself. In the brain there are at least two stages to the construction of a color image, before the main processes of interpretation and meaning. The first stage involves the perception of the intensity of a wavelength band ( V1 cells). The result of this is a grayscale view of the world, which shifts continually depending on the incident light. This stage is usually not consciously perceived. The second stage involves the comparison and contrast of several different wavebands, and produces the experience of color ( V4 cells). The color perceived depends on both the local and global variation over the field of view. [AM]

The perception of continuous motions (in the M system) is achieved at a rate of roughly 24 frames per second. This may be related to basic functions of perception in the brain, e.g. compare with the beta waves of normal consciousness (13-20 Hz), and the gamma waves of synchronized neural activity. [SFF] Depth perception is related to motion perception. [AM]

Nearly half the cerebral cortex is given over to the processing and interpretation of sight. This is the addition of meaning to the images that have been processed by the V regions. [AM]

Perception is based on change, when things don't change they eventually become imperceptible. Moreover perception is relative and relational. In a completely red room, after a period everything will look grey. [SFF] Stepping from a green lighted room into the outdoors, everything appears tinged with red [AHM].

Non-visual Perception

That the world-image of the blind, based on touch, sound, and smell, bears no inherent relationship to that of the sighted, which is integrated by visual images, has been shown by the cases of adults who have their physical sight restored after a long period of blindness. Although no longer physically blind they remain mentally blind. Although the physical structures may be operative, they still need to learn to understand, to create meaning out of their raw perceptions. The sighted do this in a very different way than the blind, being able to see many objects at the same time, to have an awareness of space. The blind have a primary awareness of time, and only know space through time. E.g. they can only measure the length of a walk by the time taken, while the sighted can stand at one end and seeing the other, judge the distance. [AM]

The newly sighted person has to go through all the development that the infant and child go through, to learn to integrate their perceptions, top build libraries of images, to construct a whole new world. This involves as well construction of a whole new self, and the letting go of, or death of the old non-visual self. This process can be very traumatic, essentially asking the person to return to the helplessness of the infant, to wipe out years of learning and adaption, and to form a whole new self. (This death and rebirth process has also be experienced by deaf people who regain their hearing) It appears that sight can not simply be integrated into the other senses, but allows, or demands, a whole new way of being, new habits and behaviors. One of these is the conscious act of looking, as opposed to the passive act of seeing, to project the awareness and attention out into the world of image in order to understand and make sense of it. [AM]

The depth of effort and difficulty with which these changes occur most clearly demonstrates the extent to which we create "our world" out of our perceptions, and that this is a process of creating our "self" as well. When the deaf learn to hear they not only create a new self, but enter a new culture, as the deaf through sign language can form a world of their own, in a way that the blind generally do not. [AM]

Learning to see as an adult is even more difficult than the task of the infant, as they are simply creating something from scratch, while the newly sighted are almost literally going through a psychological death and rebirth. It is also more difficult because the world of an adult is so much more complex than that of the infant or young child. The infant does not have to try to make sense out of the kaleidoscope of color on the shelves at the grocery store. This is also done at a stage when the brain is older, less flexible, and probably involves massive rewiring of the cortex. It is known that when one sense is lost, the other senses are enhanced, which includes physical expansion of the portions of the cerebral cortex that are used to process those senses. This may come at the expense of areas the would previously have supported the sense that has been lost. Any confidence that one has developed as a blind person is gone in the swirling confusion of new sight. In particular the sense of distance and depth is not innate, and the stability of perception that is so ingrained takes a long time to develop. This means that the person may be aware of single images, or portions of images, but the integration into dynamic objects is learned through long effort. On the other hand recognition of color and motion seem to be innate, perhaps being performed at a lower level center in the brain. [AM]

It seems that what we find to be unstable or chaotic in our perceptions is relative. With time and effort we learn to handle and interpret increasing volumes of information (probably through processes of generalization, the formation of categories etc.), or to handle new types of information. This can be clearly experienced by attending lectures where the material is either familiar or not. When it is not, much more effort is required, and usually much less understanding is garnered. Working in a foreign language may have the same effect, finally tending to put one completely to sleep, when the effort is to intense or extended. This sort of fatigue may also be experienced by the newly sighted when learning to understand their new perceptions. The creation of stability out of chaos, is also effected by filtering the incoming perceptions, reducing them to the few key components that are significant and require conscious attention. [AHM]

In persons who have lost the ability to consciously see (or experience one of the other senses) due to problems in processing areas of the brain, rather than the eyes, there may be limited implicit sight, which is apparently mediated by lower level centers and remains completely unconsciousness. [AM]

Consciousness and Perception

The sense of self or ego, which is related to the ahamtattva is intimately linked with the filters that limit the flow of sensory perceptions into awareness. The filters tend to limit inputs that are too divergent from the current world view, while the filtering of perceptions reinforces the current view. This holds for both eastern and western psychologies. The attention of the conscious mind is limited and can focus on only one input at a time. In order to cover more ground a part of the filtering system involves scanning over the incoming signals for ones that match the filters, those that are deemed to be of interest. All these systems are at some time established with some amount of judgement, either conscious or not, but in most cases once they are established they run on automatic, becoming habitual.

The vast mass of incoming sensory waves do not pass through the consciousness, but are stored directly in the unconscious mind , or the citta, without being perceived. These include many innocuous inputs that are omitted mainly to keep down the volume of material sent to the conscious mind, but some are also omitted precisely because they might upset the current sense of self and the current conscious model of the world. All these waves may, however, be recalled under hypnosis, or resurface in dreams or other ways. This vast bulk of unconscious memories serves as the foundation of the waking consciousness and will color it accordingly.

There are learning techniques in which the student listens to music (with the conscious mind) and relaxes, while the information to be learned is played at a lower volume and `heard' and remembered directly by the subconscious mind. This may be related to various subliminal techniques, where images are flashed for periods to short to consciously register, or words are played to sleeping subjects. It is noted that responses depend to some extent on content even when the conscious mind is out of the loop.

Other perceptions or experiences may pass through the consciousness but are too difficult to deal with and are "repressed", and stuffed into the unconscious parts of the mind. In western psychology these, repressed memories and emotions are viewed as the main source for the formation of the unconscious mind. In the eastern view repressed material is combined with the larger flow of filtered sensory input discussed above. Repression invests memories with energy and is actually another form of attachment. Alternately they may be "projected" externally onto other people. [See also below].

There is here the interesting issue of what makes it into consciousness? Some of this is determined by biological priorities, or the relation of information to ones ego or world view.

The interpretation of perceptions depends on existing models, in which we often key on a few specific aspects of something in order to give it meaning (e.g. the red aces of spades are generally not seen). This involves the function of memory. The earliest such model, which may serve as a reference point for all others, is one's own body image. [SFF]

See also the discussion of neuronal memory and the coherent response of the brain to perceptions.

Stability of Perception

Physical perception in humans is geared to "useful" information, which includes primarily changes in the environment. The brain is wired to be most aware of the start and stop of a sensory signal. In the case of sight, the cones of the eye are wired to emphasize edges etc. even before the signals begin processing in the brain. There is therefore a level of selection that occurs on the physical level, being inherent in the sensory organs that limits what we can perceive of the world around us. Then from the sense organ into the brain and through analysis there is a continual process of simplification, reduction in information and integration into larger wholes. This helps to maintain a relatively tractable and stable model of the world and the self.[HB]

In processing the information that comes into the brain, the comparison with memory and model, provides a layer of meaning which is generally a part of what we perceive. I.e. the red rectangle is a book, or an album cover, or a piece of paper. The integration and interpretation necessary for perceptions to have meaning is largely a function of the subconscious mind. It is with the addition of "meaning" that the emotional content of the perception is also added.

One main goal of this processing is stability, e.g. a cup is a cup is a cup, even if rotated, or the lights are changed etc. Much of the interpretation of sensory input aims to reduce the amount of variation in the raw data, e.g. changes due to distance or light levels. This leads in turn to a sense of predictability and control, as well as highlighting the changes that we need to attend to. The result is that the world we perceive is much simpler and more stable that the actual world. Our world views tend toward the simple and conservative side, in part due to biological and mental needs to reduce the input to a manageable minimum.[HB] The stability of our perception of colors given a wide variation of incident light is an example of this.

Development of Perception

In an infant, initial definitions of objects are based on motion, rather than appearance. I.e. if a partially obscured object (apparently multiple objects) moves coherently it will be recognized as a single object. Uniformity of color or texture is not generally sufficient. [SFF]

Psychic Perception

See Intuition.

[Previous] [Top] [Index] [Next]

Created March, 1998.
Last updated March 28, 2001.
© Alan McAllister

free hit counter