The Neuroscientist Karl Friston

In the vanishing ball illusion, a study found that when the magician pretends to throw the ball in the air, and his gaze follows the imaginary trajectory of the ball, almost two-thirds of the participants will be convinced that they had seen the ball move up. If his gaze did not follow the imaginary ball, the illusion was far less effective.

This illustrates that the illusion is mostly driven by expectations. Our eyes find it difficult to track fast-moving objects. Looking at the ball is only possible when we can predict where it will be in the future.

Although most participants experience an illusory effect during magic tricks, the eyes are not tricked. The conscious perception has been fooled by the illusion, but your eyes have not.

Lots of neural calculations are required before we can experience the world. Neural signals start in the retina, then it passes through different neural centers to the visual cortex and higher cortical areas, and eventually build a mental representation of the outside world. It takes about a tenth of a second for the light registered by the retina to become a visual perception. The neural delay means we perceive things at least a tenth of a second after they happened.

What is it about brain matter that gives rise to consciousness? In particular, the neuronal correlates of consciousness (NCC) - the minimal neuronal mechanisms jointly sufficient for any conscious experience.

Consider this question: What must happen in your brain for you to experience a toothache?

The whole brain can be considered an NCC because it generates experience continually.

• When parts of the cerebellum, the "little brain" underneath the back of the brain, are lost to a stroke or otherwise, patients may lose the ability to play the piano, for example.  But they never lose any aspect of their consciousness. This is because the cerebellum is almost wholly a feed-forward circuit. There are no complex feedback loops.
• The spinal cord and the cerebellum are not enough to create consciousness. Available evidence suggests neocortical tissue in generating feelings.
• The next stages of processing are the broad set of cortical regions, collectively known as the posterior hot zone, that gives rise to conscious perception. In clinical sources of causal evidence, stimulating the posterior hot zone can trigger a diversity of distinct sensations and feelings.
• It appears that almost all conscious experiences have their origin in the posterior cortex. But it does not explain the crucial difference between the posterior regions and much of the prefrontal cortex, which does not directly contribute to subjective content.

• It is different from other sensory cortices in a way that it has a multidimensional stimulus.
• Some things can smell different not just between different people but also for the same person.
• Can measure an array of an uncertain variety of chemicals that can trace changes that detects pleasure, pain, or danger.
• It does not require a map mirroring because its chemical stimulus is constantly changing. It relies on the brain to recognize the pattern or memory associated with the smell.

• Santiago Ramón y Cajal: A founding father of neuroscience, he drew attention to the sense of smell as an exemplary model to learn how the brain makes sense of the world. He also believed that understanding smell would grant us better insight into other sensory systems
• Linda Buck & Richard Axel: They discovered the olfactory receptors which happened to be the most structurally diverse and sizable member of the largest multi-gene family of protein receptors. They received the 2004 Nobel Prize in Physiology or Medicine.