Perception of Sensory Information

With analytic perceptions, visual and auditory systems use a divide and conquer strategy. Features like color, shape, and motion are processed along distinct neural pathways, but perception requires more than simply perceiving the features of objects. When gazing at the Eiffel Tower, in Paris, we do not have the impression of blurs of color floating among a sea of various shapes. We perceive unified objects : the green grass of the champ de Mars, the iron frame of the tower and the deep-blue sky surrounding it.

This famous monument looks the same whether we view it with both eyes or with only the left or the right eye. Therefore, a change in position may reveal a different part of the champ de Mars, but still recognize that we’re looking at the tower. This also remains true if we stand on our head – the retinal image may be inverted, but we attribute this change to our inverted viewing position.

Have you ever wondered how you can recognize someone face in a blurred picture or identify an object just by seeing a small part of it ? Well, numerous researchers have asked themselves that same question.

Let’s start with object perception. This type of perception depends on the analysis of the shape of a visual stimulus, even though information like color, texture, and motion contribute to normal perception. Elmer The Elephant will, like in our childhood, illustrate this for us – despite the irregularities in how this character is depicted, we have little problem in recognizing them. We may never have seen a multicolored elephant, but our object recognition system can still discern the essential features. In this case, object recognition is derived from a perceptual ability to match an analysis of shape and form.

Now this is all good and well if the world is on a two dimensional picture, yet we are all in the face of a variable world, where we need to recognize objects countless situations. And our object constancy refers to this amazing ability.


The previous image shows three drawings of a door, each having little in common with respect to sensory information reaching the eye. And yet, we have no problem identifying the door in each drawing and discerning that all three doors are same. Therefore object constancy is essential for perception. Now, imagine how difficult life would be if we could not recognize familiar things or people unless we gazed at them from a specific point of view.

While object recognition must overcome different sources of variability – the viewing position, the retina projection of shape, the changes in lighting, and the surrounding objects. It also must accommodate the fact that changes in perceived shape can reflect changes in the object. As a result, object recognition must specific enough to support object constancy, but also specific enough to pick out slight differences between members of a category.

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Social Neuroscience of Rejection – Why it hurts to be left out

If you listen closely to the ways in which people describe their experiences of social rejection, you will notice an interesting pattern : we use words representing physical pain to describe these psychologically distressing events. For example, we all know the feeling of not being picked for a workgroup, invited to a party, or even asked to join a conversation taking place among co-workers. In other words, we are all social beings, we like to be part of a group.

Picture this simple social experiment for a moment. You’re playing an online game where the players pass a ball among themselves. Every player gets a turn to throw the ball around. Yet, this doesn’t last – it wouldn’t be an experiment if it was, now would it – you begin to realize that the other two players are pitching the ball only to themselves, and not to you. After a while, you’re being completely ignored.


Now, imagine this situation in your everyday life, and two people know suddenly decide to treat you like you’re invisible – how do you think you’d feel ? Understandably, you would be confused. However, in this virtual game, you don’t know the other players and, you might suspect the game is rigged. Yet, you still feel unhappy.

Dr. Lierberman and other researchers in this field like Dr. Naomi Eisenberger have conducted research on the neural mechanisms of social pain. By watching people’s brain activity during social pain and compare it to brain activity during physical pain, researchers have managed to know if we actually experience pain when we are hurting emotionally. It turns out that the same part of the brain that is activated when we are feeling physical pain, lights up during social pain. Therefore, saying a break up is painful or that an insult is hurtful is accurately describing what you might be feeling and what is going on in your brain.

As a result, if emotional and physical pain actives the same regions on our brain, could painkillers reduce the pain of social rejection?

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