of X-ray images and music appreciation are applications of this process in the human sphere. Research has focused on the relation of this to other kinds of learning, and whether it takes place in peripheral sensory systems or in the brain's processing of sense information. Empirical research show that specific practices (such as yoga, mindfulness, Tai Chi, meditation, Daoshi and other mind-body disciplines) can modify human perceptual modality. Specifically, these practices enable perception skills to switch from the external (exteroceptive field) towards a higher ability to focus on internal signals (proprioception). Also, when asked to provide verticality judgments, highly self-transcendent yoga practitioners were significantly less influenced by a misleading visual context. Increasing self-transcendence may enable yoga practitioners to optimize verticality judgment tasks by relying more on internal (vestibular and proprioceptive) signals coming from their own body, rather than on exteroceptive, visual cues. Past actions and events that transpire right before an encounter or any form of stimulation have a strong degree of influence on how sensory stimuli are processed and perceived. On a basic level, the information our senses receive is often ambiguous and incomplete. However, they are grouped together in order for us to be able to understand the physical world around us. But it is these various forms of stimulation, combined with our previous knowledge and experience that allows us to create our overall perception. For example, when engaging in conversation, we attempt to understand their message and words by not only paying attention to what we hear through our ears but also from the previous shapes we have seen our mouths make. Another example would be if we had a similar topic come up in another conversation, we would use our previous knowledge to guess the direction the conversation is headed in. Effect of motivation and expectation A perceptual set (also called perceptual expectancy or simply set) is a predisposition to perceive things in a certain way. It is an example of how perception can be shaped by "top-down" processes such as drives and expectations. Perceptual sets occur in all the different senses. They can be long term, such as a special sensitivity to hearing one's own name in a crowded room, or short-term, as in the ease with which hungry people notice the smell of food. A simple demonstration of the effect involved very brief presentations of non-words such as "sael". Subjects who were told to