Provide an example of each. Sensation and perception work together through a processes that allows one to take in information from environmental stimuli and transfer it into data, which the brain and body use to modify behavior "Saylor. Sensation is the physical process by which one uses one's sense organs to respond to the environmental stimuli around them; while perception is interpretation of stimuli "Saylor. Through cognitive processing is how this occurs and it enables one to change behavior through the information provided.
A great example of this is illustrated in the writing of famous neurologist Dr. Oliver Sacks; he experienced prosopagnosia , the inability to recognize faces. Humans have the ability to adapt to changes in light conditions.
As mentioned before, rods are primarily involved in our ability to see in dim light. They are the photoreceptors responsible for allowing us to see in a dark room. You might notice that this night vision ability takes around 10 minutes to turn on, a process called dark adaptation.
This is because our rods become bleached in normal light conditions and require time to recover. We experience the opposite effect when we leave a dark movie theatre and head out into the afternoon sun. During light adaptation , a large number of rods and cones are bleached at once, causing us to be blinded for a few seconds. Light adaptation happens almost instantly compared with dark adaptation. Interestingly, some people think pirates wore a patch over one eye in order to keep it adapted to the dark while the other was adapted to the light.
Our cones allow us to see details in normal light conditions, as well as color. We have cones that respond preferentially, not exclusively, for red, green and blue Svaetichin, This trichromatic theory is not new; it dates back to the early 19th century Young, ; Von Helmholtz, This theory, however, does not explain the odd effect that occurs when we look at a white wall after staring at a picture for around 30 seconds.
Try this: stare at the image of the flag in Figure 3 for 30 seconds and then immediately look at a sheet of white paper or a wall. According to the trichromatic theory of color vision, you should see white when you do that.
Is that what you experienced? This is where the opponent-process theory comes in Hering, This theory states that our cones send information to retinal ganglion cells that respond to pairs of colors red-green, blue-yellow, black-white. These specialized cells take information from the cones and compute the difference between the two colors—a process that explains why we cannot see reddish-green or bluish-yellow, as well as why we see afterimages.
Color deficient vision can result from issues with the cones or retinal ganglion cells involved in color vision. Some of the most well-known celebrities and top earners in the world are musicians.
Our worship of musicians may seem silly when you consider that all they are doing is vibrating the air a certain way to create sound waves , the physical stimulus for audition. People are capable of getting a large amount of information from the basic qualities of sound waves. The amplitude or intensity of a sound wave codes for the loudness of a stimulus; higher amplitude sound waves result in louder sounds.
The pitch of a stimulus is coded in the frequency of a sound wave; higher frequency sounds are higher pitched. We can also gauge the quality, or timbre , of a sound by the complexity of the sound wave.
In order for us to sense sound waves from our environment they must reach our inner ear. Lucky for us, we have evolved tools that allow those waves to be funneled and amplified during this journey.
Initially, sound waves are funneled by your pinna the external part of your ear that you can actually see into your auditory canal the hole you stick Q-tips into despite the box advising against it. During their journey, sound waves eventually reach a thin, stretched membrane called the tympanic membrane eardrum , which vibrates against the three smallest bones in the body—the malleus hammer , the incus anvil , and the stapes stirrup —collectively called the ossicles. Both the tympanic membrane and the ossicles amplify the sound waves before they enter the fluid-filled cochlea , a snail-shell-like bone structure containing auditory hair cells arranged on the basilar membrane see Figure 4 according to the frequency they respond to called tonotopic organization.
Depending on age, humans can normally detect sounds between 20 Hz and 20 kHz. It is inside the cochlea that sound waves are converted into an electrical message. Because we have an ear on each side of our head, we are capable of localizing sound in 3D space pretty well in the same way that having two eyes produces 3D vision.
Have you ever dropped something on the floor without seeing where it went? Did you notice that you were somewhat capable of locating this object based on the sound it made when it hit the ground?
We can reliably locate something based on which ear receives the sound first. What about the height of a sound? If both ears receive a sound at the same time, how are we capable of localizing sound vertically? After being processed by auditory hair cells, electrical signals are sent through the cochlear nerve a division of the vestibulocochlear nerve to the thalamus, and then the primary auditory cortex of the temporal lobe.
Have you ever been expecting a really important phone call and, while taking a shower, you think you hear the phone ringing, only to discover that it is not? If so, then you have experienced how motivation to detect a meaningful stimulus can shift our ability to discriminate between a true sensory stimulus and background noise.
The ability to identify a stimulus when it is embedded in a distracting background is called signal detection theory. This might also explain why a mother is awakened by a quiet murmur from her baby but not by other sounds that occur while she is asleep. Signal detection theory has practical applications, such as increasing air traffic controller accuracy.
Controllers need to be able to detect planes among many signals blips that appear on the radar screen and follow those planes as they move through the sky. In fact, the original work of the researcher who developed signal detection theory was focused on improving the sensitivity of air traffic controllers to plane blips Swets, Our perceptions can also be affected by our beliefs, values, prejudices, expectations, and life experiences. The shared experiences of people within a given cultural context can have pronounced effects on perception.
For example, Marshall Segall, Donald Campbell, and Melville Herskovits published the results of a multinational study in which they demonstrated that individuals from Western cultures were more prone to experience certain types of visual illusions than individuals from non-Western cultures, and vice versa.
These perceptual differences were consistent with differences in the types of environmental features experienced on a regular basis by people in a given cultural context. In contrast, people from certain non-Western cultures with an uncarpentered view, such as the Zulu of South Africa, whose villages are made up of round huts arranged in circles, are less susceptible to this illusion Segall et al. It is not just vision that is affected by cultural factors.
Sensation occurs when sensory receptors detect sensory stimuli. Perception involves the organization, interpretation, and conscious experience of those sensations. Sensory adaptation, selective attention, and signal detection theory can help explain what is perceived and what is not. In addition, our perceptions are affected by a number of factors, including beliefs, values, prejudices, culture, and life experiences.
Not everything that is sensed is perceived. Do you think there could ever be a case where something could be perceived without being sensed? This would be a good time for students to think about claims of extrasensory perception.
Another interesting topic would be the phantom limb phenomenon experienced by amputees. Please generate a novel example of how just noticeable difference can change as a function of stimulus intensity. From this perspective, the critical defining features of perception include the exploratory actions of the perceiver and the knowledge of the events, animate and inanimate objects, and surrounding environment gained while engaged in looking, listening, touching, walking, and other forms of direct observation.
Perception often results in learning information that is directly relevant to the goals at hand, but sometimes it results in learning that is incidental to one's immediate goals. Perception becomes more skillful with practice and experience, and perceptual learning can be thought of as the education of attention.
Perceivers come to notice the features of situations that are relevant to their goals and not to notice the irrelevant features. Three general principles of perceptual learning seem particularly relevant. First, unskillful perceiving requires much concentrated attention, whereas skillful perceiving requires less attention and is more easily combined with other tasks. Second, unskillful perceiving involves noticing both the relevant and irrelevant features of sensory stimulation without understanding their meaning or relevance to one's goals, whereas skillful perceiving involves narrowing one's focus to relevant features and understanding the situations they specify.
And third, unskillful perceiving often involves attention to the proximal stimulus that is, the patterns of light or acoustic or pressure information on the retinas, cochleae, and skin, respectively , whereas skillful perceiving involves attention to the distal event that is specified by the proximal stimulus. Perceptual learning refers to relatively durable gains in perception that occur across widely different domains.
For example, at one extreme are studies demonstrating that with practice adults can gain exquisite sensitivity to vernier discriminations, that is, the ability to resolve gaps in lines that approach the size of a single retinal receptor.
At the opposite extreme, perceptual learning plays a central role in gaining expertise in the many different content areas of work, everyday life, and academic pursuits. In the realm of work, classic examples include farmers learning to differentiate the sex of chickens, restaurateurs learning to differentiate different dimensions of fine wine, airplane pilots misperceiving their position relative to the ground, and machinists and architects learning to "see" the three-dimensional shape of a solid object or house from the top, side, and front views.
In the realm of everyday life, important examples include learning to perceive emotional expressions, learning to identify different people and understand their facial expressions, learning to differentiate the different elements of speech when learning a second language, and learning to differentiate efficient routes to important destinations when faced with new surroundings.
In "nonacademic" subjects within the realm of academic pursuits, important examples involve music, art, and sports. For example, music students learn to differentiate the notes, chords, and instrumental voices in a piece, and they learn to identify pieces by period and composer. Art students learn to differentiate different strokes, textures, and styles, and they learn to classify paintings by period and artist.
Athletes learn to differentiate the different degrees of freedom that need to be controlled to produce a winning "play" and to anticipate what actions need to be taken when on a playing field.
Finally, perceptual learning plays an equally broad role in classically academic subjects. For example, mathematics students gain expertise at perceiving graphs, classifying the shapes of curves, and knowing what equations might fit a given curve.
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