I came to Dubai in and fell in love with it. I started coming back twice a year and decided to move here in , setting up Envie Events with two partners. Then it took took two years to prepare the first edition of Sensation! How much planning does Sensation take? We started preparing Ocean of White in January. In all, with build-up, security, food and beverages, cashiers, dancers, DJs, logistics, management and so on, there are about staff working on it.
The night where everyone sees the light! What else are you up to? We have very good connections with the government, which is eager to make Dubai a permanent entertainment destination. Motor Homunculus : The motor homunculus is a theoretical visualization of the locations in the cortex that correspond to motor and sensory function in the body. A threshold is the minimum level at which a given event can occur. In neuroscience and psychophysics, there are several types of sensory threshold.
The recognition threshold is the level at which a stimulus can not only be detected but also recognized; the differential threshold is the level at which a difference in a detected stimulus can be perceived; the terminal threshold is the level beyond which a stimulus is no longer detected. However, perhaps the most important sensory threshold is the absolute threshold, which is the smallest detectable level of a stimulus.
The absolute threshold is defined as the lowest intensity at which a stimulus can be detected. A classic example of absolute threshold is an odor test, in which a fragrance is released into an environment. The absolute threshold in that scenario would be the least amount of fragrance necessary for a subject to detect that there is an odor.
Smell is not the only sense with absolute thresholds. Sound thresholds can be about more than volume; they can also be about frequency. For example, humans cannot hear dog whistles. This is because dog whistles are at a frequency higher than the absolute threshold for frequency for human hearing.
Similarly, the minimum amount of light necessary to see something in the dark is the absolute threshold for vision. Every sense has an absolute threshold. There are several factors that can influence the level of absolute threshold, including adaptation to the stimulus and individual motivations and expectations.
For example, when you are in a crowded room where a lot of conversations are taking place, you tend to focus your attention on the individual with whom you are speaking. Because you are focused on one stimulus, the absolute threshold in this case, the minimum volume at which you can hear is lower for that stimulus than it would have been otherwise. Expectations can also affect the absolute threshold. If you are in a dark hallway searching for the tiny glow of a nightlight, your expectation of spotting it decreases the absolute threshold for which you will actually be able to see it.
The minimum amount of change in sensory stimulation needed to recognize that a change has occurred is known as the just-noticeable difference. The just-noticeable difference JND , also known as the difference limen or differential threshold, is the smallest detectable difference between a starting and secondary level of sensory stimulus.
In other words, it is the difference in the level of the stimulus needed for a person to recognize that a change has occurred. Turning Up the Volume : The difference threshold is the amount of stimulus change needed to recognize that a change has occurred. If someone changes the volume of a speaker, the difference threshold is the amount it has to be changed in order for listeners to notice a difference.
The JND is usually a fixed proportion of the reference sensory level. For example, consider holding a five-pound weight the reference level , and then having a one pound weight added. However, if you hold a fifty pound weight the new reference level , you would not be likely to notice a difference if one pound is added.
The absolute threshold is the minimum volume of the radio we would need in order to notice that it was turned on at all. However, determining the just-noticeable difference, the amount of change needed in order to notice that the radio has become louder, depends on how much the volume has changed in comparison to where it started.
Sensory adaptation is the decrease in the responsiveness of a sensory system that is confronted with a constant stimulus. Sensory adaptation, also called neural adaptation, is the change in the responsiveness of a sensory system that is confronted with a constant stimulus.
This change can be positive or negative, and does not necessarily lead to completely ignoring a stimulus. One example of sensory adaptation is sustained touching. On the other hand, how we interpret those sensations is influenced by our available knowledge, our experiences, and our thoughts.
This is called top-down processing. Look at the shape in Figure 3 below. Seen alone, your brain engages in bottom-up processing. There are two thick vertical lines and three thin horizontal lines. There is no context to give it a specific meaning, so there is no top-down processing involved. Figure 3. What is this image? Without any context, you must use bottom-up processing. Now, look at the same shape in two different contexts.
Surrounded by sequential letters, your brain expects the shape to be a letter and to complete the sequence. Figure 4. With top-down processing, you use context to give meaning to this image.
Figure 5. When given a context, your perception is driven by your cognitive expectations. Now you are processing the shape in a top-down fashion. One way to think of this concept is that sensation is a physical process, whereas perception is psychological. Although our perceptions are built from sensations, not all sensations result in perception.
This is known as sensory adaptation. Imagine entering a classroom with an old analog clock. Upon first entering the room, you can hear the ticking of the clock; as you begin to engage in conversation with classmates or listen to your professor greet the class, you are no longer aware of the ticking. The clock is still ticking, and that information is still affecting sensory receptors of the auditory system. The fact that you no longer perceive the sound demonstrates sensory adaptation and shows that while closely associated, sensation and perception are different.
There is another factor that affects sensation and perception: attention. Attention plays a significant role in determining what is sensed versus what is perceived. Imagine you are at a party full of music, chatter, and laughter.
You get involved in an interesting conversation with a friend, and you tune out all the background noise. If someone interrupted you to ask what song had just finished playing, you would probably be unable to answer that question. See for yourself how inattentional blindness works by watching this selective attention test from Simons and Chabris :.
One of the most interesting demonstrations of how important attention is in determining our perception of the environment occurred in a famous study conducted by Daniel Simons and Christopher Chabris In this study, participants watched a video of people dressed in black and white passing basketballs.
Participants were asked to count the number of times the team in white passed the ball. During the video, a person dressed in a black gorilla costume walks among the two teams. You would think that someone would notice the gorilla, right? Because participants were so focused on the number of times the white team was passing the ball, they completely tuned out other visual information.
Failure to notice something that is completely visible because of a lack of attention is called inattentional blindness. In a similar experiment, researchers tested inattentional blindness by asking participants to observe images moving across a computer screen.
They were instructed to focus on either white or black objects, disregarding the other color. Read more on inattentional blindness at the Noba Project website. Figure 6. Nearly one third of participants in a study did not notice that a red cross passed on the screen because their attention was focused on the black or white figures. Motivation can also affect perception. 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?
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