The Necker cube and Rubin vase can be perceived in more than one way. Humans are able to have a very good guess on the underlying 3D shape category/identity/geometry given a silhouette of that shape. Computer vision researchers have been able to build computational models for<unk>  that exhibit a similar behavior and are capable of generating and reconstructing 3D shapes from single or multi-view depth maps or silhouettes<unk>  () is the organization, identification, and interpretation of sensory information in order to represent and understand the presented information or environment. All<unk>  involves signals that go through the nervous system, which in turn result from physical or chemical stimulation of the sensory system. Vision involves light striking the retina of the eye; smell is mediated by odor molecules; and hearing involves pressure waves.<unk>  is not only the passive receipt of these signals, but it is also shaped by the recipient's learning, memory, expectation, and attention. Sensory input is a process that transforms this low-level information to higher-level information (e.g., extracts shapes for object recognition). The process that follows connects a person's concepts and expectations (or knowledge), restorative and selective mechanisms (such as attention) that influence<unk> .<unk>  depends on complex functions of the nervous system, but subjectively seems mostly effortless because this processing happens outside conscious awareness. Since the rise of experimental psychology in the 19th century, psychology's understanding of<unk>  has progressed by combining a variety of techniques. Psychophysics quantitatively describes the relationships between the physical qualities of the sensory input and<unk> . Sensory neuroscience studies the neural mechanisms underlying<unk> . Perceptual systems can also be studied computationally, in terms of the information they process. Perceptual issues in philosophy include the extent to which sensory qualities such as sound, smell or color exist in objective reality rather than in the mind of the perceiver. Although people traditionally viewed the senses as passive receptors, the study of illusions and ambiguous images has demonstrated that the brain's perceptual systems actively and pre-consciously attempt to make sense of their input. There is still active debate about the extent to which<unk>  is an active process of hypothesis testing, analogous to science, or whether realistic sensory information is rich enough to make this process unnecessary. The perceptual systems of the brain enable individuals to see the world around them as stable, even though the sensory information is typically incomplete and rapidly varying. Human and animal brains are structured in a modular way, with different areas processing different kinds of sensory information. Some of these modules take the form of sensory maps, mapping some aspect of the world across part of the brain's surface. These different modules are interconnected and influence each other. For instance, taste is strongly influenced by smell. Process and terminology The process of<unk>  begins with an object in the real world, known as the distal stimulus or distal object. By means of light, sound, or another physical process, the object stimulates the body's sensory organs. These sensory organs transform the input energy into neural activity—a process called transduction. This raw pattern of neural activity is called the proximal stimulus. These neural signals are then transmitted to the brain and processed. The resulting mental re-creation of the distal stimulus is the percept. To explain the process of<unk> , an example could be an ordinary shoe. The shoe itself is the distal stimulus. When light from the shoe enters a person's eye and stimulates the retina, that stimulation is the proximal stimulus. The image of the shoe reconstructed by the brain of the person is the percept. Another example could be a ringing telephone. The ringing of the phone is the distal stimulus. The sound stimulating a person's auditory receptors is the proximal stimulus. The brain's interpretation of this as the "ringing of a telephone" is the percept. The different kinds of sensation (such as warmth, sound, and taste) are called sensory modalities or stimulus modalities. Bruner's model of the perceptual process Psychologist Jerome Bruner developed a model of<unk> , in which people put "together the information contained in" a target and a situation to form<unk> s of ourselves and others based on social categories." This model is composed of three states: # When people encounter an unfamiliar target, they are very open to the informational cues contained in the target and the situation surrounding it. # The first stage does not give people enough information on which to base<unk> s of the target, so they will actively seek out cues to resolve this ambiguity. Gradually, people collect some familiar cues that enable them to make a rough categorization of the target. # The cues become less open and selective. People try to search for more cues that confirm the categorization of the target. They actively ignore and distort cues that violate their initial<unk> s. Their<unk>  becomes more selective and they finally paint a consistent picture of the target. Saks and John's three components to<unk>  According to Alan Saks and Gary Johns, there are three components to<unk> : #The Perceiver: a person whose awareness is focused on the stimulus, and thus begins to perceive it. There are many factors that may influence the<unk> s of the perceiver, while the three major ones include (1) motivational state, (2) emotional state, and (3) experience. All of these factors, especially the first two, greatly contribute to how the person perceives a situation. Oftentimes, the perceiver may employ what is called a "perceptual defense," where the person will only see what they want to see. #The Target: the object of<unk> ; something or someone who is being perceived. The amount of information gathered by the sensory organs of the perceiver affects the interpretation and understanding about the target. #The Situation: the environmental factors, timing, and degree of stimulation that affect the process of<unk> . These factors may render a single stimulus to be left as merely a stimulus, not a percept that is subject for brain interpretation. Multistable<unk>  Stimuli are not necessarily translated into a percept and rarely does a single stimulus translate into a percept. An ambiguous stimulus may sometimes be transduced into one or more percepts, experienced randomly, one at a time, in a process termed multistable<unk> . The same stimuli, or absence of them, may result in different percepts depending on subject's culture and previous experiences. Ambiguous figures demonstrate that a single stimulus can result in more than one percept. For example, the Rubin vase can be interpreted either as a vase or as two faces. The percept can bind sensations from multiple senses into a whole. A picture of a talking person on a television screen, for example, is bound to the sound of speech from speakers to form a percept of a talking person.
Perception
Sensory design
Affective sensation
Cognition
Social 
Motor planning
Psychodynamics
Visuospatial function