General Psychology
College of Computer Studies
Chapter 4
Topic: Sensation & Perception
Objectives:
1. Students will be able to classify the various receptors & describe the structure & functions of each.
2. They will be able to understand the nature & development of perception.
3. They will be able to discern the principles involved in the perception of objects depth, movement, time, person and special types of perception.
4. They will realize the influence of certain internal & external factors on perception.
5. They will be able to illustrate some of the uses & applications of principles in various fields.
Guide Questions:
1. Explain the sensory system.
Sensory system is a part of the nervous system responsible for processing sensory information. A sensory system consist of sensory receptors, neural pathways and part of the brain involved in sensory perception. A sensory receptors is a sensory nerve ending that responds to a stimulus in the internal and external environment of an organism. A neural pathways serve to connect relatively distant areas of the brain or nervous system, compared to the local communication of grey matter. Commonly recognized sensory systems are those for vision (which is the ability to interpret the surrounding environment by processing information that is contained in visible light), auditory (hearing), somatic sensation (touch), gustatory (taste), olfaction (smell) and vestibular (balance/movement). There are four distinct categories of receptors which react to the stimulus and initiate the process of sensation, these are Chemoreceptors, Photoreceptors, Mechanoreceptors, and thermoreceptors. A chemoreceptors or chemosensor is a sensory receptor that transduces a chemical signal into an action potential. A photoreceptors is a specialized type of neuron found in the retina that is capable of phototransduction. The great biological importance of photoreceptors is that they convert light into signals that can stimulate biological processes.The two classic photoreceptor cells are rods and cones, each contributing information used by the visual system to form a representation of the visual world, sight The rods are narrower than the cones and distributed differently across the retina, but the chemical process in each that supports phototransduction is similar.
2. Illustrate the visual perception & illusions. This is an example of visual perception. If you perceive a horse and rider, it is not just because of the visual sensation provided by the drawing. Each of the blobs is meaningless and the pattern is vague. Despite the lack of clarity, however, you may still perceive a horse and rider. Visual perception is the process by which we organize or make sense of the sensory impressions caused by the light that strikes our eyes. It involves our knowledge, expectations and motivations. Whereas sensation may be thought of as a mechanical process. An illusion is a distortion of the senses, revealing how the brain normally organizes and interprets sensory stimulation. Though illusions distort reality, they are generally shared by most people. Illusions may occur with any of the human senses, but visual illusions (optical illusion), are the most well-known and understood. The emphasis on visual illusions occurs because vision often dominates the other senses.
3. Define perception. Perception is an active process in which sensation are organized and interpreted to form an inner representation of the world. Perception may begin with sensation, but it also reflects our experiences and expectations as it makes sense of sensory stimuli. For example, a person standing fifteen feet away and a twelve-inch-tall doll right next to you may cast similar-sized images on the back of your eye, but whether you interpret the size to be a foot-long doll or a full-grown person fifteen feet away is a matter of perception that depends on your experience with dolls, people and distance.
4. Explain the external & internal cues. There are two kinds of factors and these are external and internal factors that affecting perception factors influence perception relate to the perceiver, perceived and situation. The Internal Factors reside in person concern and these include one's need, desires, personality and experience. Needs and Desire is an individual perception about stimuli is influenced by inter alia, his needs and desires at that time. Perception varies depending upon variations in his/her needs and desires from time to time. Personality is affects what is attended to perceive in the given situation. Research studies suggest that secure individuals tent to understand or perceive others as warm and self-accepting individuals perceived themselves as liked, wanted and accepted by others. Experience and knowledge serve as basis of perception. While one's successful experience enhances his/her perceptive ability, failure erodes his/her self confidence. Successful experience also helps perceiver understand stimuli with more accuracy.
People rely on external cues to make inferences about the causes of people’s behaviour. Research indicates that as we gain experience with the behaviour of a target person, these cues guide our decisions as to whether we should attribute the behaviour to dispositional or situational factors. Consistency cues eflect how consistently a person engages in some behaviour over time. We tend to perceive behaviour that a person performs regularly as indicative of his or her true motives. Consensus Cues reflect how a person’s behaviour compares to that of others. In general, acts which deviate from social expectations provide us with more information about the actor's motives than conforming behaviours do. Distinctiveness Cues reflect the extent to which a person engages in some behaviour across a variety of situations. When a person’s behaviour occurs across a variety of situations and lacks distinctiveness we are prone to make a dispositional attribution about its cause. Attribution in Action We often have information at hand about consistency, consensus, and distinctiveness, and we tend to use this information whenever we judge people and their behaviour. High consistency, low consensus, and low distinctiveness results in a dispositional attribution. High consistency, high consensus, and high distinctiveness results in a situational attribution. Biases in Attribution Despite our best efforts in attributing and interpreting behaviour, several errors and biases can occur in the attribution process.
5. What are the characteristics of the perciever? The perceiver's experience, motives, and emotions can affect his or her perceptions. Experience. One of the most important influences on perception is experience - our past experiences lead us to develop expectations and these affect current perceptions - differences in perception caused by experience can lead to problems within organizations. Motivational State. Differences in our needs at a given moment and our motivational state can also be a source of conflict within organizations, since our motivational states influence our perception and interpretation of events. Emotional State. Emotional state refers to the particular emotions that an individual feels at a given time. Emotions such as anger, happiness, or fear can and do affect our perceptions. In some cases we employ a perceptual defense which occurs when our perceptual system serves to defend us against unpleasant emotions. In general, we tend to "see what we want to see."
6. What are the types of perception? The way human beings derive meaning through the senses, including ears, eyes and touch is what makes man to stand out from the rest of the animate beings. Owing to the complexity of deduction depending on what the senses perceive, different kinds of interpretations emerge. It is these that form the different types of perception in psychology that include amodal, color, depth, form, speech, harmonic pitch and rhythmic perceptions. There are seven types of perceptions these are, amodal, color, speech, harmonic, rhythmic, depth, and form perception.
1. Amodal perception is one of the most recognizable types of perception in psychology. It is the observation and interpretation of things in terms of depth and motion. For instance, even if one sees only three points in a triangular object, he or she knows that the object is three-dimensional and that there are hidden points on the other side.
2. Color perception, on the other hand, describes the way the visual senses, denoting the eyes, observe hues and contextualize them in the environment. For example, by interpreting blue as the color of depression, the eyes will tend to always attribute all things of this tinge to be melancholic.
3. The other types of perception in psychology include those that interpret verbal output. Speech perception, for one, helps in not only understanding one another, but deducing meaning from mere sounds. It also indicates the mechanical arrangement of the vocals when another person speaks which means that the listener interprets the speech through the phonetics such as syllables to create meaning.
4. Harmonic perception, on the other hand, owes to the understanding that the ear usually perceives inter-related notes, as one, to create meaning in sounds. For instance, riffs in a guitar mixed with those of other instruments lead to interpretation of the music as a single output that is simple to listen to rather than one that actually consists of different notes.
5. Rhythmic perception also follows the same theories in its interpretative methodology, whereby the ear gets into a groove by practically responding to it. For instance, one can easily listen to a beat while humming along to it or tapping along as it continues courtesy of its rhythmic harmony.
6. Depth perception also acts as one of the types of perception psychology. It relates to the way the human eye identifies and contextualizes things in space. For instance, though the naked eye cannot see the end of a tunnel, it interprets its possible depth through past experiences such as scientific measurements to know how deep the tunnel can be.
7. Form perception indicates the contextualization of particular objects in a given environment, whereby the eyes sees them as primarily 2-D and at times as 3-D depending on the way of their placement. It is also the understanding of what characterizes the inner and outer core of an object. After seeing an orange, one immediately knows that it is round and has a rough texture on the skin that protects the soft interior.