Sensation and Perception: Understanding How We Experience the World
Feeling
Our behavior is a result of the complexity of cognitive and affective variables. However, all that wealth and flexibility is thanks to our biological structure. Thus, to understand our behavior, we must begin by understanding the biological bases that regulate our thoughts and emotions.
Our body has two fundamental systems that allow us to coordinate and integrate behavior: the Nervous System and the Endocrine System.
The nervous system consists of two subsystems, each one responsible for different functions:
- Central Nervous System (CNS) is involved in related functions, sensitivity, and body movement, and
- Peripheral Nervous System (PNS), also called Autonomic or Neurovegetative, regulates the physiological functions (circulation, respiration, digestion, etc.) that are beyond our control.
The SNP, in turn, is composed of the somatic system (SS) and the Autonomic (SA). The latter is in control of the sympathetic and parasympathetic divisions. However, perceptual issues occur and are made possible by this structure.
Definitions:
Feeling: Process and guidance built inland where the information enters the environment and is transformed into electrical impulses and chemicals. Your information is meaningless. The feeling is the basic interaction with a medium body and is defined as the experience of sensory stimulation (Morris, 1995).
Perception: Integration, organization, and interpretation of information that comes from senses and experience.
Imagination: The process of creation, representation of items that are not in reality. It builds on the creative process of human beings. Integration exists, whose sum is new and unexpected results.
The Senses
The environment generates stimuli to the body, which in turn stimulate specialized receptor cells that respond to a specific type of energy.
Stimulus:
Any form of energy that produces a response in a sensory organ that produces energy that we can respond to, like sound waves, light waves, etc..
Directions:
Channel or a particular physiological pathway that responds to a specific type of energy. The senses are the avenues of communication that take our body to the outside world. The sense organs are those that provide information about the world and capture the environment.
Sensory Operations
For the sense organs to respond to stimulation, it is necessary for the present stimulus to be strong enough to react to the recipient cell. The way it reacts is by an electrochemical signal to be encoded specializing in the road that runs to the brain, where the message is more accurate and detailed in terms of stimulating the areas of sensory coding. Specifically, these signals in the brain create sensory experiences that are in turn decoded and interpreted through the process of perception.
Scientists have listed about 12 different human senses and there may be others. The senses play four roles in perception:
- Detection
- Transduction
- Transmission
- Information Processing
1. Detection
The elements that detect sensory stimuli are called receptors, and each has a specific meaning.
In each direction, there are receptors sensing elements sensitive to a specific type of energy.
The receivers are sensitive to a limited range of stimuli.
Eg Our ears respond to vibrations of air in a range of 20 to 20000 hertz (cycles per second). The vibrations above and below this range are not audible by people.
Sensory Thresholds
- Absolute thresholds. These are the values of minimum magnitude of the stimulus, which are necessary for detection. If the magnitude of the stimulus is too weak, subthreshold or subliminal, it produces a detection response, on the other hand, the magnitude of the stimulus above the threshold are called suprathreshold or supraliminal.
- Differential thresholds. A measure of the minimum difference between two stimuli that can be detected. Ie is the smallest difference in intensity between two stimuli that can be perceived.
Sensory Adaptation
It is an accommodation in the sensory against prolonged exposure to a stimulus or set of stimuli. Ie given the large amount of stimulation that exists in the environment, the organism has learned to lower levels of sensory receptors response compared to continuous stimulation. Eg the sound of cars outside the hall is a stimulation which we are not aware of, or the temperature of the place.
Selective Attention
Attention is a provision of our cognition, effecting a choice between many offers of perceptible phenomena, because it is perceived that precisely matches the existing motives and ignores or are deemed less clear what is not located in the area of motivation. Ie we focus the attention on those stimuli that generate interest (note that some stimuli are impossible to ignore).
The sensory thresholds equal the minimum and maximum intensities of physical energy intensity required to produce a sensation.
2 to 3. Transduction and Transmission
The receptors transduce, ie convert energy from one form to another. Recipients receive stimulation, make energy as electrochemical signals entering the nervous system uses for communication.
If this energy is of sufficient intensity, triggers nerve impulses that transmit coded information about the different characteristics of the stimulus. The impulses travel through nerve fibers to regions of the brain.
4. Information Processing
Both the brain and the process sensory receptors in animals and more complex the brain has a greater responsibility in this role.
Organs of the Senses
View The view is the most important of our senses, since it offers the most complete and detailed information from the outside world. As estimated, 80 percent of all the information that reaches the brain to perceive through the eyes. The structures for vision are the eyeballs, protective structures, and neural pathways ópticas.El stimulus consists of electromagnetic waves (light) for the visible spectrum that affect the retina, which are located receptors called rods and cones, nerve cells excited by light.
The rods are sensitive only to the dim light, as used in night vision, the cones are for daylight vision, plus they are only sensitive to color.
Among the disturbances of color vision of the most important are:
Color blindness, or inability to perceive any color except white, black, and gray.
Daltonism, namely the confusion between red and green.
Tritanopia, which consists of non-discrimination between blue and green.
Other vision disorders are myopia, astigmatism, hyperopia, presbyopia, etc.
Ear Hearing along with vision, are the most useful way we have, because as our primary warning system against potentially dangerous environmental situations. In addition, both directions are mutually supportive, so that when one of them low performance, the other becomes more acute as compensation. The ear is the organ of hearing, and is responsible for generating the auditory perception. It is also essential for the balance or spatial orientation. It is divided into three parts: the outer ear, middle ear, and inner ear.
The stimulus consists of sound waves received by the outer ear and through the middle ear, reach the inner which is located in the organ of Corti (spiral) whose hair cells are excited by the waves, transforming the sound energy into an electrical impulse. The auditory nerve transmits the electrical impulse to their relevant area of the brain.
The sounds are distinguished by the wavelength and frequency. The lowest frequency you can hear the man is 20 cycles / sec, the largest of 20,000 cycles / sec.
The sound qualities are:
Intensity, which depends on the amplitude of sound waves.
The tone, caused by the frequency, the pitched at a high frequency response, the serious low.
The timbre, which depends on the harmonious sounds that accompany the main sound. It is the timbre that differentiates one sound emitted by a piano or violin or voice differentiate between a person and another.
Taste The taste has the task of identifying the flavors through the perception of its chemical qualities. The taste and smell function in complement, so that they have been called the chemical senses. The stimuli are the substances in liquid form. Saliva has, among other things, dissolve substances within the mouth to taste it. The taste is perceived through taste buds, which are concentrated in the mucosa of the tongue and to a lesser extent, on the palate and pharynx. The papillae are distributed unevenly in the language and all perceive the four basic types of flavors, but some taste react more strongly to certain stimuli, so that the tip of the tongue captures the sweetness, the bitter be seen in the back, and salty tastes sour or bitter sit on the sides of the body. The rest of the flavors are sensations, resulting from the combination of these four, stimulated by the odors emanating from food.
Smell The stimuli are volatilized substances that excite olfactory receptors located on the top of the nostrils. By this sense, we perceive smells, indefinite in number, have tried various classifications of odors, all highly debatable.
Compared with other features, the smell is of secondary importance in our lives, however, is the most sensitive way, as it stimulates surprisingly low concentrations of molecules of a substance. As we saw earlier, smell and taste are intertwined. In addition, smell acts as a detector that warns us of dangers such as toxic or poisonous gases, or rotting food. The sense of smell resides, specifically in the nostrils, which are located behind the nose and mouth above.
Touch Touch is responsible for the perception of stimuli that include contact and pressure, temperature, and pain. His sensory organ is the skin, which also has the distinction of being the largest organ of the body. The perception of these external stimuli are made through specific receptor cells that each one of these signals in the skin. It is estimated that in human skin there are about four million sets for the sensation of pain, pressure 500 000, 150 000 to 16 000 to cold and heat.
Vestibular System
With its receptors in the inner ear is the sense of moving our body in space. In this way, we provide essential information to orient in space, maintaining a stable visual field even though our head or body are moving. It also allows us to coordinate the movement of both sides of the body, such as by cutting with scissors, buttoning, biking, etc.. and anticipate the movement in space and time, as to tackle a ball or jump rope.
Proprioception
With its receptors in muscles, tendons, and joints, allow us to know where every part of our body and how it is moving, without using sight. This provides us with essential information to take skill and coordination, both in our gross motor skills (running, jumping, etc..) And manual functions (writing, cutting) and oral motor control (eating, talking.) It allows us to grade the strength of muscle contraction and do the movements right time (timing), to be effective.
With its receptors in muscles, tendons, and joints, allow us to know where every part of our body and how it is moving, without using sight.
Kinesthetic
Informs us of the power of our muscles. Mediante this sense coordinate the actions of our muscles automatically. The receptor organs are few nerve endings located in the tendons and joint boards.
An anomaly in this sense produces an irregular or uncoordinated movements. If you close your eyes and someone else puts us arms crossed, for example, we know that we cross.
Interoceptive
Informs us of our internal organs, for example, a full bladder.
Perception
Perception is the process by which integrates sensory awareness of objects, events, or situations and turns them into useful experience. The collection includes the interpretation of these sensations, giving meaning and organization (Matlin and Foley 1996). The organization, interpretation, analysis, and integration of stimuli, the activity involves not only our sense organs, but also of our brain (Feldman, 1999). In humans on a more complex question of how the brain translates the signals or stimuli collected.
However, it is important to note that perception is not a simple mechanical process. For example, if invited several artists to paint the same landscape, each of them gives a different picture. Each viewer of a film can tell us about the different things you have observed, several witnesses to an accident or event we have various versions. Perceive not only a body but each event is recorded by many and the slightest deviation in each can lead to considerable variations in each person. If everyone receives the same material with certain differences, if the description of the descriptor that speaks more of the above, we can repeat the proposal of the philosopher Kant:”We see things not as they are but as we are”
Perception then:
- It is the cognitive process through which individuals organize and interpret their sensory impressions in order to give meaning to their environment.
- It allows us to understand and make sense of the feelings we experience continuously. It should be understood that the information coming from the senses is not made. This function is carried out by the perception (Morris, 1995; Torres, 2002).
Perception involves two processes (Bruner et al. 1958):
- The selection of the enormous volume of data that we receive from abroad, reducing complexity and enabling storage and retrieval in memory.
- An attempt to go beyond the information obtained to predict future events and, thereby, prevent or reduce the surprise.
Is influenced by:
- External signals (stimuli)
- Internal signals (personal factors), motivation, past experience or expectations at any given time, can act as internal signals.
Perceptual Process
Gestalt Principles of Organization
Gestalt theory posits that we perceive objects as”al” well-organized, rather than as separate and isolated. The”everythin” we see is something more structured and consistent than a group of isolated fragments, the shape is more than just the union of the fragments.
Max Wertheimer (1923), Kurt Koffka (1935), and Wolfgang Köhler (1947), in the twentieth century began the task of discovering the principles that interpret sensory information. These principles are structured into two main laws: Law and law background figure or fitness (also called clustering or terseness)
Figure and background law: that a stimulus is felt, should be contrasted with the environment. Individuals organize stimuli in form and substance:
- The figure is the central element that captures most of our attention because, in contrast to its background, is well defined, solid, and headlines.
- The fund, poorly differentiated, is perceived as indefinite, vague, and continuous.
While people tend to organize their perceptions in terms of figure and ground, will depend on the learning process the decision about which stimuli are perceived as figure and what the background.
Act in good shape: refers to a principle of organization of the elements of a perceptual experience and the Gestalt called Pregnancies (Prägnanz). This mechanism can reduce possible ambiguity or distortion, always seeking the simplest and the most consistent, in short, allows us to see the materials as meaningful and consistent.
In addition, the Law on Physical Fitness is governed by a set of basic principles:
- Near: When objects are near each other tend to perceive them together and not separate.
- Similarity: Objects of color, size, or shape such is often seen as part of a pattern.
- Closing: we tend not to notice the incompleteness of sensory information and warnings a whole object, even if there in reality.
- Continuity: We tend to cluster as part of a pattern of objects that follow a pattern or direction.
Perceptual records
It is the tendency to perceive objects as unchanging despite changes produced by sensory stimulation. Once we have formed a stable perception of the object, recognize it from almost any angle. In this way, the constancy of size, shape, and color helps us to have a stable configuration of reality allowing us to relate better with it.
- Shape constancy: the tendency to see an object as having the same size, no matter from what angle we look at it.
- Color constancy: the inclination to perceive familiar objects as if they retain their color, even when they found the changes of sensory information.
- Size constancy: perception of an object as having the same size regardless of the distance from which we see.
- Evidence of Brilliance: perception of brightness as if it were the same, despite changing the amount of light reaching the retina.
Perceptual Predisposition
This concept refers to how our past experiences, our expectations, our prejudices, etc., Influence what we perceive. We often see, hear, taste, smell, etc., Which we expect or what fits our preconceptions.
Depth Perception
Ability to see objects in three dimensions although the images that captures the retina are two-dimensional. Enables distances. This is partly innate capacity.
Types of Perception
1. Sensory perception: perception is real and objective information that is collected and made from direct observation of the stimulus that impresses the sensory receivers.
2. Perception consecutively or post-sensory perception: Determined by the sensory image persistence after the stimulus has disappeared, usually after it has been very intense. Is intermediate between perception and representation.
3. Pareidolia: Also called illusions fantastic productions consist of creative fancy, from a sensory material fuzzy boundaries.
Visual Illusions
False interpretation of a sensory image, it is not for perceived physical characteristics”objectiv” of estímulo.Existe a stimulus (the object), the sensory receptors are normal but there is a failure of integration and distorted perception. The stimulus contains misleading signals that cause the creation of perceptions that are inaccurate, and even impossible.
This deformation is given in relation to the care, affection, and conscience.
Involving multiple factors: neurophysiological, emotional, and personality.
- Real presence of the stimulus or object.
- Deformation of the perceived.
- No absolute conviction of reality.
- Correctable in healthy subjects.
Subliminal Perception
Subliminal perception refers to the collection of messages that we have in consciousness. The stimulus may be a word, a sound, or a smell that triggers the sensory system, but it is not intense enough to have experienced an individual developing.
ESP: Fact or fantasy?
Ability to perceive events in ways that cannot be explained by known sensory abilities (telepathy, precognition, clairvoyance)
In summary, the perception:
- It works in conjunction with the sensation, attention, memory, emotions, and higher processes.
- Depends on culture, experience, motivation, interest, brain structure, and proper configuration of the senses.
Characteristics of the observer: personal variables that contribute to the organization and interpretation of sensory information.
Motivation: People who have a desire or need to tend to see more easily what they think will satisfy you.
Values: values lead us to differentially perceive those with whom we share something at the expense of those with whom we disagree.
Expectations: influenced by what they perceive hope to see.
Cognitive style: As we mature, we acquire and develop a style of learning, understanding, seeing things, which in turn affects how we perceive:
The perception Culturaafecta:
- Shaping stereotypes
- Directing attention
- Telling us what is important and not